liu.seSearch for publications in DiVA
12 1 - 50 of 78
rss atomLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
  • Henneberg, Joel
    Linköping University, Department of Electrical Engineering.
    Development of a Rule Based Decision Support System for Pilots: Using Network Analysis, Label Propagation and Association Rule Mining2023Independent thesis Advanced level (degree of Master (Two Years)), 28 HE creditsStudent thesis
    Abstract [en]

    Maneuvering a fighter jet is not easy, and new methods for minimizing the risk of pilots experiencing information overload are constantly under development. Saab is currently looking into the possibilities of creating a decision support system (DSS) for pilots in situations where multiple independent system failures occur simultaneously. In today’s JAS 39 Gripen E such failures generate multiple simultaneous alerts for the pilots to act upon, with each alert proposing a set of actions for the pilot to handle the current situation. These actions are displayed on separate pages for each of the alerts, requiring the pilot to manually swap between pages of actions to get an overview of what to do. When pilots must use a significant part of their cognitive abilities to maneuver the aircraft in critical situations, a DSS is needed to apprehend the information and guidelines from the alerts more quickly.

    Our approach to developing such DSS is by representing each of the individual actions as nodes in a network, with links between nodes providing information about the relations between actions. The purpose of mapping the problem to become a networking problem is to use label propagation algorithms to divide the network into communities. With each node being assigned to a community and having the communities sorted on priority, getting a first draft of what a sorting algorithm can accomplish should be easy given a complex fault situation. We use rule mining to extract rules from the system as it is currently implemented to create a rule-based sorting within communities.

    The conclusion regarding label propagation algorithms is that although they are great for prototyping, propagation algorithms have no place in creating a DSS with high reliability. We also conclude that inconsistencies in the data that yield cycles in the created networks limit the sorting algorithms since there is no way of knowing where the cycle begins, hence no way of knowing how to sort actions being part of a cycle. Despite this, we argue that mined rules can be very helpful for engineers at Saab to be more consistent in their future work. Because of this, the conclusion is that our prototype of the DSS is better suited for the engineers working with providing pilots with the correct information than for the pilots directly. Lastly, we provide suggestions for future work, focusing much on possible ways of dealing with the cycles. Suppose Saab wants to pursue further research into whether creating a good enough DSS the way we propose is possible. In that case, some filter has to be developed to reduce the amount of information in complex fault situations.

    Download full text (pdf)
    fulltext
  • Naumovska, Elena
    et al.
    Chalmers University of Technology, Sweden.
    Nzulu, Gabriel Kofi
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Mazzei, Laura
    Chalmers University of Technology, Sweden.
    Le Febvrier, Arnaud
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Komander, Kristina
    Uppsala University, Sweden.
    Magnuson, Martin
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Wolff, Max
    Uppsala University, Sweden.
    Eklund, Per
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Karlsson, Maths
    Chalmers University, Sweden.
    Local structure of hydrated nanocrystalline films of the proton conductor BaZr1-Sc O3-/2 studied by infrared spectroscopy2024In: Vibrational Spectroscopy, ISSN 0924-2031, E-ISSN 1873-3697, Vol. 130, article id 103622Article in journal (Refereed)
    Abstract [en]

    We report results from a study of the local structure of hydrated nanocrystalline 2 �m films of the well known proton conductor BaZr1-xScxO3-x/2 with x = 0.45, 0.54 and 0.64, using infrared (IR) spectroscopy. The films were prepared by magnetron sputtering. Analysis of the IR spectra focused on the O–H stretching region (2000—3700 cm-1), which reveals the presence of several distinct O–H stretching bands for which the intensity and frequency of each band vary in an unsystematic manner with Sc concentration. The spectra for the two higher Sc concentrations, x = 0.54 and 0.64, exhibit a distinct, highly intense O–H stretching band centered at around 3400–3500 cm-1, which is assigned to relatively symmetric, weakly hydrogen-bonding, proton configurations. The spectrum for the lower Sc concentration, x = 0.45, does not feature such a band but a broader, weaker, O–H stretching band between approximately 2500 and 3700 cm-1, suggesting that the protons are more homogeneously distributed over a range of different local proton coordinations in this relatively weakly doped material. A comparison to the IR spectra of powder samples of similar compositions suggests that for x = 0.45, the spectra and proton coordination of films and powder samples are similar, whereas for x = 0.54 and 0.64, a larger fraction of protons seems to be located in weakly hydrogen-bonding proton configurations in the films compared to the respective powder samples.

    Download full text (pdf)
    fulltext
  • Lidén, Tomas
    et al.
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Häll, Carl Henrik
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Utformning av underhållsområden på större driftplatser - verksamhetsstudie2023Report (Other academic)
    Abstract [sv]

    Denna rapport ger en kunskapsgrund om de praktiska förutsättningarna, kravbild, och forskningsläge för utformning av underhållsområden på större driftplatser. Rapporten inleds med en bakgrund och motivering till behovet av underhållsområden, samt en beskrivning av hur studien har genomförts. En genomgång av förutsättningar och begränsningar visar bland annat att de tekniska delsystemen (spår-, signal-, och elkraftsystem) måste beaktas eftersom de har olika sektionering, gränspunkter och skyddsgivning för de arbeten som behöver utföras, samt att trafikeringsbehoven och dess variation behöver beskrivas på en generell nivå (oberoende av en specifik tidtabell), både vad gäller linjetrafik, växling och uppställning. 

    Det centrala kapitlet är en krav- och behovsanalys. Där dokumenteras först vilka allmänna egenskaper som fördefinierade underhållsområden behöver uppfylla, varefter tre avsnitt följer som diskuterar specifika behov som ställs av de tre verksamhetsgrenarna underhåll, planering, och trafikledning. Ett viktigt resultat är att inga stora målkonflikter har identifierats vad gäller utformningen av underhållsområden samt att en samstämmighet råder om att trafikpåverkan bör vara den huvudsakliga värderingsgrunden för områdenas utformning. Den genomförda litteraturstudien har identifierat en relativt omfattande forskning om olika partitioneringsproblem, men bara ett fåtal publikationer inom rälsbundna transporter. För hantering av kapaciteter på driftplatser finns det metoder som kan hantera en övergripande trafikbild, men ännu inget bra stöd för analys av restkapacitet vid olika typer av tidsbegränsade spårreduktioner. Någon forskning om kombinationen av partitionering, eller indelning i underområden, av en driftplats bestående av flera delsystem där målet är att kunna hantera trafikbelastningen så bra som möjligt på den resterande spårkapaciteten har vi inte kunnat finna. 

    Vi rekommenderar att Trafikverket vidareutvecklar sitt metodstöd för utformning av underhållsområden inom ramen för målområdet som arbetar med servicefönster. Både i detta metodstöd och för framtida forskning tror vi att den identifierade probabilistiska kapacitetsmodellen för driftplatser kan vara en lämplig grund. 

    Arbetet har utförts i förstudieprojektet UFO (Utformning av underhållsområden på större driftplatser), finansierat av Trafikverket (FoI-portfölj Vidmakthålla, ärende-ID 7742, diarienummer TRV2022/138570) via branschprogrammet KAJT, Kapacitet i järnvägstrafiken (www.kajt.org).

    Download full text (pdf)
    fulltext
    Download (png)
    presentationsbild
  • Johansson, Britt-Inger
    Linköping University, Department of Behavioural Sciences and Learning.
    Elevers berättelser om skolfrånvaro och närvarofrämjande insatser: En narrativ studie2023Independent thesis Advanced level (degree of Master (Two Years)), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Skolfrånvaro är ett omdebatterat ämne som i olika rapporter och i forskning lyfts fram som ett samhällsproblem. Forskningen är omfattande, både nationellt och internationellt. Eftersom tillräckliga kunskaper saknas om elevers erfarenheter av skolfrånvaro så är det ett perspektiv som behöver belysas mer. Studiens syfte är att bidra med kunskaper om hur skolan kan arbeta för att främja skolnärvaro genom att undersöka problematisk skolfrånvaro ur ett elevperspektiv. Studien tar sin utgångspunkt i en narrativ metod. Genom livsberätteler bidrar ett antal elever med kunskap om närvarofrämjande insatser utifrån egna erfarenheter av skolfrånvaro inom gymnasieskolan. Jag intervjuade sex elever från fyra olika kommuner samtliga med erfarenheter av skolfrånvaro i gymnasieskolan. Eleverna studerade inom både yrkesförberedande och studieförberedande program. En elev hade erfarenhet av gymnasieskolans introduktionsprogram. Studien fokuserar på tre huvudsakliga frågeställningar: Vilka orsaker till skolfrånvaro framträder i elevernas berättelser, vilka erfarenheter har elever av närvarofrämjande insatser samt vilka insatser väljer elever själva att lyfta fram som viktiga i ett närvarofrämjande arbete? Jag valde en kvalitativ forskningsansats och utgick från en tematisk ostrukturerad intervjuguide då det därigenom fanns en större möjlighet för informanten att själv förmedla den bild de vill ge av sitt liv.

    Studiens teoretiska ansats utgår från specialpedagogiska teorier och innefattas av det kompensatoriska och relationella perspektivet. Därutöver tillkommer de teoretiska begreppen; inkludering, delaktighet och exkludering. Studiens teoretiska ram har även utvidgats med begreppet KASAM. Känslan av sammanhang är grundläggande inom Antonovskys salutogena teori om hälsa.

    Resultatet visar att det finns många orsaker till elevers skolfrånvaro och att orsakerna är komplexa. Elevers erfarenheter av närvarofrämjande insatser ser olika ut eftersom arbetet skiljer sig åt både mellan och inom skolor. Elever har förslag på hur skolor kan arbeta för att främja skolnärvaro.

    Download full text (pdf)
    Masteruppsats, specialpedagogik
  • Ringia Vallin, Agnes
    Linköping University, Department of Behavioural Sciences and Learning.
    Pedagogisk dokumentation i förskolan: En undersökning av förskollärares uppfattningar om sitt arbete med pedagogisk dokumentation2023Independent thesis Advanced level (degree of Master (Two Years)), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Denna studie undersöker förskollärares uppfattningar om sitt arbete med pedagogisk dokumentation. Datamaterial har samlats in med hjälp av semistrukturerade intervjuer av förskollärare. Studiens utgångspunkt är fenomenografiska teoretiska perspektiv.

    Studiens resultat utgörs av tre kategorier av uppfattningar, där den första är innehåll i förskollärares arbete med pedagogisk dokumentation. Förskollärarna i denna studie uppfattar pedagogisk dokumentation som ett styrningsverktyg utifrån styrdokument, en arbetsmetod för att synliggöra lärande samt som ett sätt att synliggöra förskollärarens profession och praktik. I den andra kategorin, pedagogisk dokumentation som svårt och komplext uppdrag, lägger förskollärarna i denna studie fokus på yttre- och praktiska förutsättningar. Det handlar om innehållsmässiga svårigheter kring vad som ska dokumenteras, arbetsbörda på grund av saknad kompetens och tid, samt svårigheter att hantera teknik och digital dokumentation. Den tredje kategorin, barns delaktighet i arbete med pedagogisk dokumentation, fokuserar förskollärarna i denna studie på barns kompetens. Förskollärarna uppfattar ofta barnen som inkompetenta och passiva, med begränsad rätt till inflytande och integritet i pedagogisk dokumentation.

    Studien bidrar med kunskap kring förskollärares uppfattningar om sitt arbete med pedagogisk dokumentation i förskolan. Att belysa variationer i förskollärares uppfattningar skapar möjlighet till yrkesmässig reflektion och fördjupning. Resultatet av den här studien kan ge förskollärare och rektorer verktyg för reflektion för att utveckla arbete med pedagogisk dokumentation i sin praktik.

    Download full text (pdf)
    fulltext
  • Peressini, Gaia
    Linköping University, Department of Management and Engineering, The Institute for Analytical Sociology, IAS.
    Residential segregation in saturated housing markets: Using vacancy chains to analyze moving patterns in Stockholm2023Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis uses vacancy chain analysis to investigate the complex dynamics of residential segregation within Stockholm County. Residential segregation has been a longstanding concern due to its implications for social inequality and community cohesion. While previous research has explored various factors contributing to segregation, this study focuses on understanding the intricate processes that drive neighborhood-level changes in occupancy patterns by analyzing the role of newly built dwellings. By studying the characteristics of the people that first move to the new dwellings and then the chains they create, the aim is to uncover segregating or desegregating patterns, which could prove essential for future residential planning.

    The findings presented in this thesis shed light on the interconnected roles of individual preferences, socio-economic factors, and neighborhood characteristics in shaping segregation patterns and provide important insights for designing targeted interventions to promote more equitable and integrated communities. Neighborhoods that fall into the fourth income decile exhibit the most considerable desegregating effect both for first and subsequent moves. Knowing this, targeting housing construction for lower-income neighborhoods could produce the best results.

    Download full text (pdf)
    fulltext
  • Lee, Bumjin
    Linköping University, Department of Culture and Society, Division of Migration, Ethnicity and Society (REMESO).
    Looking into the Identity of Korean Transnational Adoptees in Sweden: Pivoting on the Correlation between Microaggression and Racialization Experience in the Daily Life2023Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Diplomatic relations between Sweden and South Korea enabled international adoption. It progressed mostly between the 1960s and the 1980s. Concerning the aim for both countries, Sweden needed clear-cut and positive evidence to demonstrate the following social change: From race biology to multiculturalism. South Korea needed the foreign capital for national development. Adoptees were adopted without any appropriate support and deprivation of self determination, and they had to situate the discrimination and identity problem in Swedish society because of the absence of whiteness. This study is not only unpacking problems of identity for Korean transnational adoptees in Sweden but also deducing meaningful outcomes by looking into their stories through an in-depth interview.

    Download full text (pdf)
    fulltext
  • Cordova, Stephanie
    et al.
    Linköping University, Department of Management and Engineering, Environmental Technology and Management. Linköping University, Faculty of Science & Engineering.
    Gustafsson, Marcus
    Linköping University, Department of Management and Engineering, Environmental Technology and Management. Linköping University, Faculty of Science & Engineering.
    Eklund, Mats
    Linköping University, Department of Management and Engineering, Environmental Technology and Management. Linköping University, Faculty of Science & Engineering.
    Svensson, Niclas
    Linköping University, Department of Management and Engineering, Environmental Technology and Management. Linköping University, Faculty of Science & Engineering.
    What should we do with CO₂ from biogas upgrading?2023In: Journal of CO2 Utilization, ISSN 2212-9820, E-ISSN 2212-9839, Vol. 77, article id 102607Article in journal (Refereed)
    Abstract [en]

    Carbon capture and utilization has been proposed as an essential climate change mitigation strategy, but only a few implemented cases exist. During biomethane production from anaerobic digestion, CO₂ is commonly separated and emitted into the atmosphere, which can be utilized as raw material for various products. This research aims to identify and assess CO₂ utilization alternatives for possible integration with biogas upgrading from anaerobic digestion by developing a soft multi-criteria analysis (MCA). A literature review complemented with stakeholder participation enabled the identification of relevant alternatives and criteria for assessment. Potential alternatives for CO₂ utilization include methane, mineral carbonates, biomass production, fuels, chemicals, pH control, and liquefied CO₂. Results show that although no alternative performs well in all indicators, there is an opportunity for short-term implementation for methane, biomass production, mineral carbonates, liquefied CO₂, and pH control. Moreover, the uncertainty analysis reveals that even though the technologies have a high technological development, more information on critical aspects is still required. The soft MCA provides information to decision-makers, practitioners, and the academic community on learning opportunities of the alternatives and indicators to step from development into implementation. For instance, the method can be used to assess more specific systems with different locations and scales or to direct efforts to ease the implementation of CCU.

    Download full text (pdf)
    fulltext
  • Public defence: 2024-01-19 09:00 Belladonna, LinköpingOrder onlineBuy this publication >>
    Ahlbeck, Lars
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Inflammation and Infection. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Medicine Center, Allergy Center.
    Intralymphatic Immunotherapy: A Novel Route to Ameliorate Allergic Rhinitis Due to Pollen2024Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Allergy to pollen and animal dander is a major public health problem. Close to 30% of the population have symptoms from the upper and/or lower respiratory tract when they meet fur animals or pollen. Whereas symptom-relieving medications have a good to sufficient effect on about 80% of those affected, a large group of 10–20% have severe symptoms, despite medication, with an impact on well-being and ability to work. In Sweden, the annual cost of allergy was calculated at €1.3 billion in 2014.

    Immunotherapy is effective in treating and preventing pollen allergy and allergic asthma, but is expensive, complicated, requiring 40 injections, and takes more than three years to complete if subcutaneous injections are used. Tablets placed under the tongue are another method, with one tablet taken every day for three years. Only 1.5‰ receive such treatment, yet just over 3% would need it.

    With intralymphatic immunotherapy, a small dose of allergen is given in a lymph node in the groin on 3 occasions, one month apart. As this method takes only eight weeks, it is a much faster and less costly treatment. However, although several studies have shown that the treatment is safe, its efficacy remains the subject of doubt.

    Our pilot study in 2012, with a 3-year follow-up to 2015, showed encouraging results, and was followed by a double-blind randomised study with 72 participants from 2014 to 2018. The research subjects then received treatment with birch and grass pollen extract or one extract and a placebo. Regardless of treatment, symptoms, quality of life and medication consumption improved during the birch and grass pollen seasons in the 3 years after treatment. Increased frequencies of T-regulatory lymphocytes may explain the non-specific effects.

    In 2017 to 2018, we conducted a double-blind study with 38 participants, half of whom received placebo and half, active treatment. In this study, we saw no difference between the treatment groups in the first year after treatment. However, after discontinuation and unblinding in 2019, i.e., two years after treatment, the actively treated group improved in terms of symptoms, and quality of life was improved compared with the placebo group despite less need for medication. T-regulatory lymphocytes increased one year after treatment only in the actively treated group.

    A long-term follow-up of the research subjects from our two larger studies in 2022, i.e., five to eight years after treatment, showed in the double-blind study without a pure placebo that the scores for symptoms, medication use, and quality of life remained as low as after the first three years. In the placebo-controlled study, a statistically significant improvement in symptoms remained during the grass pollen season. Analysing the two studies together, symptom improvement was significant even during the birch pollen season. Thus, although the effect does not seem to diminish, those who did not receive birch, but only grass, needed to use more medication during the birch pollen season in 2022, seven to eight years after treatment. Moreover, those who did not receive grass but only birch needed more medication during the grass pollen season. This may suggest that the non-specific effect begins to wane after seven to eight years.

    Allergy to pollen is a major problem for individuals and society, where symptom-relieving treatment with drugs is not enough for many. They can be helped with immunotherapy, which takes at least three years, is expensive and fraught with side effects. In contrast, intralymphatic immunotherapy involves three injections over eight weeks. Our three studies show that the treatment is safe and indicate that it has a clinical effect up to eight years after treatment. T-regulatory cells appear to be important to the immunological mechanism, leading to tolerance to pollen.

    List of papers
    1. Intralymphatic allergen immunotherapy against pollen allergy. A 3-year open follow-up study of 10 patients
    Open this publication in new window or tab >>Intralymphatic allergen immunotherapy against pollen allergy. A 3-year open follow-up study of 10 patients
    Show others...
    2018 (English)In: Annals of Allergy, Asthma & Immunology, ISSN 1081-1206, E-ISSN 1534-4436, Vol. 121, no 5, p. 626-627Article in journal (Refereed) Published
    Abstract [en]

    To date, allergen immunotherapy (AIT) is the only treatment that affects the long-term development of allergic rhinoconjunctivitis and induces clinical tolerance primarily by stimulating regulatory T (Treg) cells, attenuating T helper 2 (Th2) responses and synthesis of blocking antibodies1. Conventional AIT with subcutaneous injections, sublingual tablets or drops is effective, but consumes time and resources 2.

    Place, publisher, year, edition, pages
    Elsevier, 2018
    Keywords
    Immunotherapy, Intralymphatic, Allergy, Rhinoconjunctivitis, T-cells
    National Category
    Clinical Medicine
    Identifiers
    urn:nbn:se:liu:diva-150594 (URN)10.1016/j.anai.2018.07.010 (DOI)000448665400022 ()30021119 (PubMedID)
    Note

    Funding agencies: Region Ostergotland; Allergy Center in Linkoping; Medical Research Council of Southeast Sweden (FORSS); Bergh Foundation; Asthma and Allergy Association of Sweden

    Available from: 2018-08-28 Created: 2018-08-28 Last updated: 2023-11-27Bibliographically approved
    2. Intralymphatic immunotherapy with one or two allergens renders similar clinical response in patients with allergic rhinitis due to birch and grass pollen
    Open this publication in new window or tab >>Intralymphatic immunotherapy with one or two allergens renders similar clinical response in patients with allergic rhinitis due to birch and grass pollen
    Show others...
    2022 (English)In: Clinical and Experimental Allergy, ISSN 0954-7894, E-ISSN 1365-2222, Vol. 52, no 6, p. 747-759Article in journal (Refereed) Published
    Abstract [en]

    Introduction

    There is a need for a fast, efficient and safe way to induce tolerance in patients with severe allergic rhinitis. Intralymphatic immune therapy has been shown to be effective.

    Methods

    Patients with severe birch and timothy allergy were randomized and received three doses of 0.1 ml of birch and 5-grass allergen extracts (10,000 SQ units/ml, ALK-Abello), or birch and placebo or 5-grass and placebo by ultrasound-guided injections into inguinal lymph nodes at monthly intervals. Rhinoconjunctivitis total symptom score, medication score and rhinoconjunctivitis quality of life questionnaire were evaluated before treatment and after each birch and grass pollen season during three subsequent years. Circulating proportions of T helper subsets and allergen-induced cytokine and chemokine production were analysed by flow cytometry and Luminex.

    Results

    The three groups reported fewer symptoms, lower use of medication and improved quality of life during the birch and grass pollen seasons each year after treatment at an almost similar rate independently of treatment with one or two allergens. Mild local pain was the most common adverse event. IgE levels to birch decreased, whereas birch-induced IL-10 secretion increased in all three groups. IgG4 levels to birch and timothy and skin prick test reactivity remained mainly unchanged. Conjunctival challenge tests with timothy extract showed a higher threshold for allergen. In all three groups, regulatory T cell frequencies were increased 3 years after treatment.

    Conclusions

    Intralymphatic immunotherapy with one or two allergens in patients with grass and birch pollen allergy was safe, effective and may be associated with bystander immune modulatory responses.

    Place, publisher, year, edition, pages
    Chichester, United Kingdom: Wiley-Blackwell Publishing Inc., 2022
    Keywords
    allergy; intralymphatic immunotherapy; hypersensitivity; rhinoconjunctivitis immunotherapy; intralymphatic; allergy
    National Category
    Respiratory Medicine and Allergy
    Identifiers
    urn:nbn:se:liu:diva-184407 (URN)10.1111/cea.14138 (DOI)000776517300001 ()35332591 (PubMedID)2-s2.0-85127382771 (Scopus ID)
    Note

    Funding Agencies: Region Östergotland; Medical Research Council of Southeast Sweden (FORSS); Th Bergh Foundation; Asthma and Allergy Association

    Available from: 2022-04-21 Created: 2022-04-21 Last updated: 2023-11-27Bibliographically approved
    3. Intralymphatic immunotherapy with birch and grass pollen extracts. A randomized double-blind placebo-controlled clinical trial
    Open this publication in new window or tab >>Intralymphatic immunotherapy with birch and grass pollen extracts. A randomized double-blind placebo-controlled clinical trial
    Show others...
    2023 (English)In: Clinical and Experimental Allergy, ISSN 0954-7894, E-ISSN 1365-2222, Vol. 53, no 8, p. 809-820Article in journal (Refereed) Published
    Abstract [en]

    IntroductionThere is a need to evaluate the safety and efficacy of intralymphatic immunotherapy (ILIT) for inducing tolerance in patients with allergic rhinitis. MethodsThirty-seven patients with seasonal allergic symptoms to birch and grass pollen and skin prick test >3 mm and/or IgE to birch and timothy >0.35 kU/L were randomized to either ILIT, with three doses of 0.1 mL of birch pollen and 5-grass pollen allergen extracts on aluminium hydroxide (10,000 SQ-U/ml; ALK-Abello) or placebo using ultrasound-guided intralymphatic injections at monthly intervals. Daily combined symptom medical score and rhinoconjunctivitis total symptom score were recorded during the peak pollen seasons the year before and after treatment. Rhinoconjunctivitis total symptom score, medication score and rhinoconjunctivitis quality of life questionnaire were recorded annually starting 2 years after treatment. Circulating proportions of T helper cell subsets and allergen-induced cytokine and chemokine production were analysed using flow cytometry and ELISA. ResultsThere were no differences between the groups related to daily combined symptom medical score the year before and after treatment. Two years after ILIT (after unblinding), the actively treated group reported significantly fewer symptoms, lower medication use and improved quality of life than did the placebo group. After the pollen seasons the year after ILIT, T regulatory cell frequencies and grass-induced IFN-gamma levels increased only in the actively treated group. ConclusionIn this randomized controlled trial, ILIT with birch and grass pollen extract was safe and accompanied by immunological changes. Further studies are required to confirm or refute the efficacy of the treatment.

    Place, publisher, year, edition, pages
    WILEY, 2023
    Keywords
    allergy; hypersensitivity; intralymphatic immunotherapy; rhinoconjunctivitis
    National Category
    Respiratory Medicine and Allergy
    Identifiers
    urn:nbn:se:liu:diva-193405 (URN)10.1111/cea.14307 (DOI)000962776700001 ()37013723 (PubMedID)
    Note

    Funding Agencies|Astma- och Allergifoerbundet; Region OEstergoetland; Medical Research Council of Southeast Sweden (FORSS); Bergh Foundation

    Available from: 2023-05-03 Created: 2023-05-03 Last updated: 2023-11-27
    Download full text (pdf)
    fulltext
    Download (png)
    presentationsbild
  • Forsgren, Johanna
    Linköping University, Department of Behavioural Sciences and Learning, Education, Teaching and Learning. Linköping University, Faculty of Educational Sciences.
    Att organisera för hälsofrämjande och förebyggande elevhälsa: En studie om specialpedagogens yrkesroll2023Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Denna kvalitativa studie syftar till att undersöka specialpedagogers uppfattningar omelevhälsans främjande och förebyggande arbete utifrån deras yrkesroll. Uppsatsen fokuserar påframgångsfaktorer och specialpedagogens roll i ett hälsofrämjande och förebyggande samt vadbegreppet elevhälsa uppfattas stå för. För att skapa förståelse för det specialpedagoger berättarligger ett relationellt specialpedagogiskt perspektiv till grund för studiens analys. Arbetetinspirerades av grundad teori och genomfördes som en intervjustudie med semistruktureradeintervjuer, bestående av fem enskilda intervjuer med specialpedagoger. Intervjuerna ochtranskriberingarna av dem pågick till dess att mättnad uppnåtts. Grundad teori är en induktivmetod och studien har kommit fram till att genom att ha ett relationellt specialpedagogisktförhållningssätt i elevhälsoarbetet ökar möjligheten till ett mer främjande och förebyggandearbete.

    Skollagen och läroplanen för grundskolan slår fast att det i varje svensk skola ska finnas enelevhälsa. Däremot beskrivs det inte någonstans hur ett sådant arbete ska organiseras, det liggerpå varje huvudman eller skola att besluta om. Informanterna i denna studie uttrycker att det ärotydligt vad elevhälsobegreppet står för. Det kan syfta till professionerna, insatserna, elevernashälsa eller den samlade elevhälsan. I studien framkommer att elevhälsoarbetet är hela skolansansvar och för att lyckas med det behöver det finnas en samsyn kring hur begreppet ska förståssamt en tydlig och strukturerad organisation av arbetet. Informanterna poängterar vikten av entydlig ledare i elevhälsoarbetet och beskriver rektor som den givna ledaren som ska organiseraför ett främjande och förebyggande elevhälsoarbete som genomsyrar hela verksamheten. Detframkommer tydligt att rektors arbete påverkar hur väl skolan lyckas i sitt elevhälsoarbete. Iresultatet framträder specialpedagogen som en nyckelperson i elevhälsoarbetet genom att isamverkan med andra upptäcka, göra bedömningar och analysera samt planera och genomföraåtgärder på både organisations-, grupp- och individnivå. Vidare framkommer att rektor ochspecialpedagog kompletterar varandra och att det är framgångsrikt för elevhälsoarbetet när dearbetar nära varandra. Resultatet visar att detta sammantaget ger implikationer för detspecialpedagogiska arbetet på skolorna. Studien kan därför inspirera specialpedagoger i detfrämjande och förebyggande elevhälsoarbetet. 

    Download full text (pdf)
    fulltext
  • Malmström, Magnus
    et al.
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, Faculty of Science & Engineering.
    Skog, Isaac
    Uppsala University, Sweden.
    Axehill, Daniel
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, Faculty of Science & Engineering.
    Gustafsson, Fredrik
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, Faculty of Science & Engineering.
    On the validity of using the delta method for calculating the uncertainty of the predictions from an overparameterized model2023In: Special issue: 22nd IFAC World Congress / [ed] Hideaki Ishii, Yoshio Ebihara, Jun-ichi Imura, Masaki Yamakita, Elsevier, 2023, Vol. 56, no 2, p. 5843-5848Conference paper (Refereed)
    Abstract [en]

    The uncertainty in the prediction calculated using the delta method for an over-parameterized (parametric) black-box model is shown to be larger or equal to the uncertainty in the prediction of a canonical (minimal) model. Equality holds if the additional parameters of the overparameterized model do not add flexibility to the model. As a conclusion, for an overparameterized black-box model, the calculated uncertainty in the prediction by the delta method is not underestimated. The results are shown analytically and are validated in a simulation experiment where the relationship between the normalized traction force and the wheel slip of a car is modelled using e.g., a neural network.

    Download full text (pdf)
    fulltext
  • Ayoub, Yohan
    Linköping University, Department of Computer and Information Science, Artificial Intelligence and Integrated Computer Systems.
    Multi-agent route planning for uncrewed aircraft systems operating in U-space airspace2023Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Society today brings a high pace development and demand of Artificial intelligence systems as well as robotics. To further expand and to take one step closer to have Unmanned Aerial Vehicles (UAVs) working in the cities, the European Union Aviation Safety Agency launched a project that introduces U-space airspace, an airspace where UAVs, for instance, are allowed to operate for commercial services.The problems defined for U-space airspace resemble problems defined in the area of multi-agent path finding, such as scaling and traffic etc., resulting an interest to research whether MAPF-solutions can be applied to U-space scenarios. The following thesis extends the state-of-the-art MAPF-algorithm Continuous-time Conflict based search (CCBS) to handle simplified U-space scenarios, as well as extend other A*-based algorithms, such as a version of the Receding Horizon Lattice-based Motion Planning named Extended Multi-agent A* algorithm with Wait-Time (EMAWT) and an extended A* named Extended Multi-agent A* algorithm (EMA) to handle them. Comparisons of the three algorithms resulted in the EMAWT being the most reliable and stable solution throughout all tests, whilst for fewer agents, the CCBS being the clear best solution.

    Download full text (pdf)
    fulltext
  • Public defence: 2023-12-18 09:00 Berzeliussalen, LinköpigOrder onlineBuy this publication >>
    Boano, Gabriella
    Linköping University, Department of Health, Medicine and Caring Sciences, Division of Diagnostics and Specialist Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Surgical Ablation of Atrial Fibrillation with Cryo and Radiofrequency Concomitant to Mitral Valve Surgery: Clinical, Biochemical and Echocardiography Outcomes2023Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Atrial fibrillation (AF) is the most common arrhythmia seen in clinical practice. In cardiac surgery, the negative influence of AF on short- and long-term outcomes has made concomitant ablation procedures more common. The indications, clinical aspects, results, risks, and benefits of the additional surgical ablation are still valuable topics for discussion. This compilation thesis consists of four papers aiming to investigate some of the clinical, biochemical, and echocardiographic aspects of surgical ablation for AF (Cox-Maze IV) when performed concomitant to mitral valve surgery (MVS).

    Through a retrospective, case-control, single-center study, we described the impact of the Cox-Maze IV procedure added to MVS with focus on postoperative heart failure (paper I).

    Cryoenergy (cryo) and radiofrequency (RF) are the two different energy sources mainly used in Cox-Maze IV for AF ablation. To achieve linear scars in the atrial wall, the RF procedure uses heat damage, whereas the cryo method freezes down to -150°C. Through a prospective, randomized, longitudinal, controlled study, we compared the biochemical responses of the two ablative methods in concomitant MVS and the release of enzymes expressing myocardial injury, as well as inflammatory, cell stress, and apoptosis-specific proteins. We could show that cryo results in a larger release of markers for myocardial damage but has no impact on the early inflammatory response (paper II).

    Extended scar lesions resulting after maze may influence atrial function. As the left atrium plays a key role in the altered cardiac hemodynamics in AF, an echocardiographic analysis of the effects of the Cox-Maze IV procedure concomitant to MVS on the left atrium was carried out. The impacts of the two energy sources (cryo and RF) on left atrial remodeling and function had not been compared previously. Their direct effect on left atrial remodeling and mechanical function were assessed 1 year after surgery in patients with restored sinus rhythm. Sinus rhythm restoration after MVS concomitant to Cox-Maze IV results in a reduced left atrium size regardless of the energy source used. Three-dimensional echocardiography showed that, compared to RF, the extension of the ablation area produced by cryo implies major left atrium structural remodeling affecting systolic function. The negative effect on left atrium remodeling seems to be linear with the duration of the AF (paper III).

    An overview of the pacemaker implantation rate after the Cox-Maze IV procedure concomitant to MVS was obtained in a multicenter study using national qualitative registers (SWEDHEART, Carath, Svenska ICD- och Pacemakerregistret) (paper IV, sumbitted).

    Our results contribute to optimizing surgical indications and patient selection, providing a deeper understanding of the biochemical and echocardiographic changes during and after surgical ablation.

    List of papers
    1. Cox-maze IV cryoablation and postoperative heart failure in mitral valve surgery patients
    Open this publication in new window or tab >>Cox-maze IV cryoablation and postoperative heart failure in mitral valve surgery patients
    2017 (English)In: Scandinavian Cardiovascular Journal, ISSN 1401-7431, E-ISSN 1651-2006, Vol. 51, no 1, p. 15-20Article in journal (Refereed) Published
    Abstract [en]

    OBJECTIVE: The indications for and the risk and benefit of concomitant surgical ablation for atrial fibrillation (AF) have not been fully delineated. Our aim was to survey whether the Cox-maze IV procedure is associated with postoperative heart failure (PHF) or other adverse short-term outcomes after mitral valve surgery (MVS).

    DESIGN: Consecutive patients with AF undergoing MVS with (n = 50) or without (n = 66) concomitant Cox-maze IV cryoablation were analysed regarding perioperative data and one-year mortality.

    RESULTS: The patients in the Maze group were younger, were in lower NYHA classes, had better right ventricular function and had lower pulmonary artery pressure. The Maze group had 30 min longer median cross-clamp time (CCT) and 50% had PHF compared with 33% in the No-maze group, p = 0.09. Two patients in the No-maze group died within one year of surgery. Congestive heart failure (OR 4.3 [CI 95%: 1.8-10], p < 0.0001) and CCT (OR 1.03 [CI 95%: 1.01-1.04], p = 0.001) were associated with PHF.

    CONCLUSION: The current data cannot exclude that concomitant cryoablation increases the risk for PHF, possibly by increasing the cross clamp time.

    Place, publisher, year, edition, pages
    Taylor & Francis, 2017
    National Category
    Clinical Medicine
    Identifiers
    urn:nbn:se:liu:diva-134010 (URN)10.1080/14017431.2016.1196827 (DOI)000392468400003 ()27248647 (PubMedID)
    Note

    Funding agencies: ALF funding, County Council of Ostergotland, Sweden

    Available from: 2017-01-18 Created: 2017-01-18 Last updated: 2023-11-23
    2. Biochemical response to cryothermal and radiofrequency exposure of the human myocardium at surgical ablation of atrial fibrillation: a randomized controlled trial
    Open this publication in new window or tab >>Biochemical response to cryothermal and radiofrequency exposure of the human myocardium at surgical ablation of atrial fibrillation: a randomized controlled trial
    Show others...
    2020 (English)In: Translational Medicine Communications, ISSN 2396-832X, Vol. 5, article id 11Article in journal (Refereed) Published
    Abstract [en]

    Background: Surgical cryothermia and radiofrequency (RF) ablations for atrial fibrillation (AF) seem to result in similar sinus rhythm restoration, but the biochemical consequences of the two methods are unclear. We aimed to compare the biochemical responses to the two ablative methods in concomitant mitral valve surgery (MVS).

    Methods: Sixty mitral valve surgery patients with AF were prospectively included. Forty-one patients planned for ablation were randomized to cryothermia (n = 20) or radiofrequency (n = 21) ablation and 19 served as controls. Markers for myocardial injury, inflammation, cell stress, apoptosis, and heart failure were analyzed pre- and postoperatively at different time points.

    Results: Troponin T and creatine kinase isoenzyme MB (CK-MB) peak levels were significantly higher in the cryothermia group compared with the RF group (12,805 [6140–15,700] vs. 2790 [1880–4180] ng/L; P = 0.002 and 271 [217–357] vs. 79 [66–93] μg/L; P < 0.001, respectively). Both groups had significantly higher levels than the no-ablation group. There were no group differences in C-reactive protein (CRP) and N-terminal pro-B-type natriuretic peptide (NT-proBNP), but there were correlations between pre- and postoperative levels of both CRP (rs = 0.41, P = 0.001) and NT-proBNP (rs = 0.48, P < 0.001). Protease-activated receptor 1 (PAR-1) and heat shock protein 27 (HSP27) were significantly increased in the cryoablation group.

    Conclusions: Cryoablation results in a larger myocardial injury and possibly more elevated apoptotic activity and cell stress compared with the RF technique. The type of ablation device did not have any significant influence on the postoperative inflammatory response nor on the early postoperative levels of NT-proBNP.

    Place, publisher, year, edition, pages
    BioMed Central, 2020
    National Category
    Surgery
    Identifiers
    urn:nbn:se:liu:diva-174088 (URN)10.1186/s41231-020-00064-z (DOI)
    Note

    Funding agencies: The Swedish Heart-Lung Foundation, grant number 20160391, the ALF founding, County Council of Östergötland, Sweden. Open access funding provided by Linköping University.

    Available from: 2021-03-14 Created: 2021-03-14 Last updated: 2023-11-23Bibliographically approved
    3. Effect of cryothermic and radiofrequency Cox-Maze IV ablation on atrial size and function assessed by 2D and 3D echocardiography, a randomized trial. To freeze or to burn
    Open this publication in new window or tab >>Effect of cryothermic and radiofrequency Cox-Maze IV ablation on atrial size and function assessed by 2D and 3D echocardiography, a randomized trial. To freeze or to burn
    2023 (English)In: Clinical Physiology and Functional Imaging, ISSN 1475-0961, E-ISSN 1475-097XArticle in journal (Refereed) Epub ahead of print
    Abstract [en]

    BackgroundAtrial linear scars in Cox-Maze IV procedures are achieved using Cryothermy (Cryo) or radiofrequency (RF) techniques. The subsequent postoperative left atrial (LA) reverse remodelling is unclear. We used 2- and 3-dimensional echocardiography (2-3DE) to compare the impact of Cryo and RF procedures on LA size and function 1 year after Cox-maze IV ablation concomitant with Mitral valve (MV) surgery. MethodsSeventy-two patients with MV disease and AF were randomized to Cryo (n = 35) or RF (n = 37) ablation. Another 33 patients were enroled without ablation (NoMaze). All patients underwent an echocardiogram the day before and 1 year after surgery. The LA function was assessed on 2D strain by speckle tracking and 3DE. ResultsForty-two ablated patients recovered sinus rhythm (SR) 1 year after surgery. They had comparable left and right systolic ventricular function, LA volume index (LAVI), and 2D reservoir strain before surgery. At follow-up, the 3DE extracted reservoir and booster function were higher after RF (37 & PLUSMN; 10% vs. 26 & PLUSMN; 6%; p &lt; 0.001) than Cryo ablation (18 & PLUSMN; 9 vs. 7 & PLUSMN; 4%; p &lt; 0.001), while passive conduit function was comparable between groups (24 & PLUSMN; 11 vs. 20 & PLUSMN; 8%; p = 0.17). The extent of LAVI reduction depended on the duration of AF preoperatively. ConclusionsSR restoration after MV surgery and maze results in LA size reduction irrespective of the energy source used. Compared to RF, the extension of ablation area produced by Cryo implies a structural LA remodelling affecting LA systolic function.

    Place, publisher, year, edition, pages
    WILEY, 2023
    Keywords
    3D volumes; atrial fibrillation; atrial strain; left atrium; mitral valve surgery; surgical ablation
    National Category
    Cardiac and Cardiovascular Systems
    Identifiers
    urn:nbn:se:liu:diva-196761 (URN)10.1111/cpf.12841 (DOI)001017553400001 ()37334891 (PubMedID)
    Note

    Funding Agencies|ALF Grant Region Ostergotland

    Available from: 2023-08-22 Created: 2023-08-22 Last updated: 2023-11-23
    Download full text (pdf)
    fulltext
    Download (png)
    presentationsbild
  • Wadström, Christoffer
    et al.
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Johansson, Maria
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Uddin, Gazi Salah
    Linköping University, Department of Management and Engineering, Economics. Linköping University, Faculty of Arts and Sciences.
    Navigating uncertainty: exploring electricity demand dynamics in Swedish industrial sectors amid global shocksand instability2023In: Energy Efficiency, ISSN 1570-646X, E-ISSN 1570-6478, article id 95Article in journal (Refereed)
    Abstract [en]

    This study aims to provide insights into the factors shaping electricity demand in Swedish industrial sectors using the nonlinear version of the autoregressive distributed lag model (NARDL). This approach captures the complex short- and long-run relationships between uncertainty and electric power use in Swedish industrial sectors. The results reveal sector-specific responses to uncertainties and asymmetries in electricity use patterns. By examining the entire industrial sector in Sweden, this approach uncovers underlying issues and hidden patterns, while also providing insights into the functioning and behaviour of industrial systems. The rapid electrification and new green industrialisation initiatives in Sweden, coupled with the integration of a circular economy, underscore the importance of understanding the dynamics of electricity use in the face of uncertain shocks. This knowledge is vital for ensuring, amongst other things, grid stability, mitigating the need for costly peaking capacity, and identifying potential challenges in the interconnection of energy and material circular flows

    Download full text (pdf)
    fulltext
  • Agerstig Rosenqvist, Morgan
    Linköping University, Department of Science and Technology, Physics, Electronics and Mathematics. Linköping University, Faculty of Science & Engineering.
    Evaluation of algorithms for accurate micro-doppler effects measurement in FMCW radar2023Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Micro-Doppler effects are phenomena that occur because of micro-motion. A micro-motion is either a vibration, rotation, or acceleration which is small relative to the motion of the target. These effects can be used in order to characterize a target through their signature movement. These effects were captured using a Frequency Modulated Continous Wave (FMCW) radar on several targets with a distinct signature. The targets were a four-armed drone, a cyclist, and a pedestrian. Using conventional- and super-resolution algorithms allows the user to process the captured data. To best be able to determine these signatures, different algorithms were used, Short-Time Fourier Transform (STFT), Smoothed Pseudo-Wigner-Ville Distribution (SPWVD), Pade Fourier approximation (PFA), and MUltiple SIgnal Classification (MUSIC). The comparison of the algorithms on the measured data was done in MATLAB where the best possible scenario was taken. From the comparison, it was noticed that in order to capture the most details, the MUSIC, PFA, STFT, and SPWVD performed the best with a decreasing order.

    Download full text (pdf)
    fulltext
  • Henriksson, Amanda
    et al.
    Linköping University, Department of Management and Engineering. Linköping University, Faculty of Arts and Sciences.
    Wennerström, Isabelle
    Linköping University, Department of Management and Engineering. Linköping University, Faculty of Arts and Sciences.
    Hållbarhetsstyrning & rapporteringskvalitet: En kvantitativ studie om styrsystem till följd av tvingande hållbarhetsrapportering2023Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Background: Increasing demand for sustainability information during the last two decades has led to enactment of mandatory sustainability reporting, for example through Directive 2014/95/EU. As a result of mandatory sustainability reporting, companies must integrate sustainability management control systems to comply with reporting requirements. 

    Purpose: The purpose of this paper is to explain how sustainability management has been affected due to mandatory reporting on sustainability and how sustainability management has affected the quality of sustainability reporting.

    Research method: The study applies a quantitative method through content analysis and quasi-experiments. The content analysis is carried out on ten Swedish listed companies’ annual- and sustainability reports for the fiscal years 2013-2022.

    Results: The result shows that mandatory regulation has a positive relationship with sustainability management. Cultural-, administrative- and cybernetic controls have had the greatest increase due to mandatory regulation. Furthermore, there is a positive relationship between sustainability management and reporting quality. 

    Contributions: This study contributes to the literature on the relationship between sustainability management and sustainability reporting. It also makes a methodological contribution through a constructed sustainability management control index.

    Download full text (pdf)
    fulltext
  • Humla, Johan
    et al.
    Linköping University, Department of Management and Engineering, Fluid and Mechatronic Systems.
    Friman, Samuel
    Linköping University, Department of Management and Engineering, Fluid and Mechatronic Systems.
    Development of a Hydraulic Front Wheel Drive for a Battery Electric Truck2023Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This master thesis work has been executed at Volvo GTT in Gothenburg. Focus has beenlaid on implementing a hydraulic front wheel drive (HFWD) system on a battery electricvehicle (BEV). The earlier concept builds have been performed on internal combustionengine (ICE) driven trucks at Volvo Trucks. The main difference in implementing thesystem on a BEV lies in the change of power take-off (PTO) which on a BEV is totallyindependent of the driving engine and cannot use the idle for rotating the charge pumpduring the inactive mode of the HFWD system. On the other hand, this opens up increasedcontrollability with many possibilities for improving the efficiency of the system. 

    Using efficiency maps of selected components, simulations have been performed tofind out the final energy consumption. Those are partly for the engaged mode where theHFWD is active and partly for when it is inactive. Different control strategies are comparedfor the active mode, including variating the electric motor, hydraulic pump, or both. Forthe inactive mode, one concept using a separate electric motor for a separate charge pumpand one concept removing the charge pump and running the main pump in cycles arecompared with the reference concept.

    The work resulted in a component- and CAD specification for a reference concept readyto be built within the near future, together with two concepts that can improve the energyefficiency of the HFWD system when operating in the disengaged mode. Results are alsoachieved for the active mode. Simulations show that controlling the pressure and flowby both the electric motor and the hydraulic pump is theoretically the most efficient, butmight bring difficulties in practice. The simulation analysis of the inactive mode showsthat fitting a separate DC motor for the charge pump will lower the disengaged energyconsumption by around 50%. Simultaneously, investigations show that removing thecharge pump completely might be an interesting way of designing the system, dependingon what temperature conditions the application will be used it may decrease the energyconsumption. 

    Our recommendation is to first build the reference concept according to the specificationpresented in the report on an actual truck to be able to validate the simulations. Thereafter the practical results can be evaluated and solutions from the alternative concepts beinserted with improved efficiency as a preliminary outcome.

    Download full text (pdf)
    fulltext
  • Andersson, Elise
    et al.
    Möbelkonservator på Nationalmuseum, styrelsemedlem i Malmstens Alumni.
    Brunne, UlfOrdförande i Malmstens Alumni, snickarmästare och möbelkonservator f.d. studierektor på Malmstens (LiU).Helgesson, RobinAnställd på Spågan möbelkonserevring AB, styrelsemedlem i Malmstens Alumni, möbelsnickare och möbelkonservator .Vaher, LauriLinköping University, Department of Management and Engineering, Malmstens Linköping University. Linköping University, Faculty of Science & Engineering.
    Proceedings of the symposium Woodworking Tools and Techniques – Past, Present and Future, Stockholm 16-19 September 20222023Conference proceedings (editor) (Other academic)
    Abstract [en]

    The 3rd Swedish Symposium on Furniture Technology& Design was held in Stockholm the 16th through the19th of September 2022, this time arranged by MalmstensAlumni in collaboration with the Swedish History Museum,Skokloster Castle and LiU Malmstens.

    Contents:

    Foreword page 6Ulf Brunne, Chairman, Malmstens Alumni

    Woodworking Tools and Techniques – Technical and Aesthetical Aspects of Furniture Design and Cabinetmaking through the Ages page 7Johan Knutsson, Professor in Furniture Culture LiU Malmstens, Sweden

    From Tool Marks to Work Practises page 14Hans Piena, Curator of Domestic Culture, Dutch Open Air Museum, The Netherlands

    Characteristics of Japanese Woodworking Tools page 21Kenji Komatsu, Woodworker/Artist, Wood Workshop BYHAND, Japan

    A Reconstruction of an Early 16th Century Tondo Frame page 29Iskander Breebaart, Senior Furniture Conservator Rijksmuseum, The Netherlands

    Wave Mouldings and Ornamental Lathe page 37Josephine Erckrath, Cabinetmaker and Furniture Conservator Møbelarkitekt Tyge Axel Holm, Denmark

    Dutch Moulding Planes from Skokloster Castle, Sweden page 42Jaap Boonstra, Furniture Conservator, Amsterdam Museum, The Netherlands, Pol Bruijs, Furniture Conservator, Private Practise, The Netherlands

    Mahogany Spheres – Reconstruction of an Artistically Crafted Element of a Writing Cabinet by the Berlin Ebenist Joseph Schneevogl (1795–1864) page 54Prof. Dr. Angelika Rauch, University of Applied Sciences, Potsdam, GermanyDipl.-Rest. Jörg Weber, Head of Workshop, University of Applied Sciences Potsdam, Germany

    Construction Features that are Typical for Marquetry Cabinets by Jan van Mekeren page 60Paul van Duin, Head of Furniture Conservation, Rijksmuseum, The NetherlandsIskander Breebaart, Senior Furniture Conservator, Rijksmuseum, The Netherlands

    Australian Timbers and Contemporary Woodworking page 68Evan Dunstone, Dunstone Design, Australia

    Woodworking as Means for Understanding and Developing the Human-Technology Relationship – Discussed Through the Work of Cabinet Maker Thomas Tempte page 74Andreas Nobel, Professor in Furniture Design LiU Malmstens, Sweden

    The Future of Furniture Craft Education – a Churchill Fellowship page 80Joseph Bray, Head of Wood School Sylva Foundation, UK

    Applied Information Technology and Mathematics in Woodturning page 86Ulf Jansson, Engineer and Woodturner Private Practise, Sweden

    Download full text (pdf)
    fulltext
    Download (png)
    presentationsbild
  • Ask, Sandra
    Linköping University, Department of Culture and Society.
    Criticizing Patriarchal Traditions through Alternative History in Carol Ann Duffy's The World's Wife2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Download full text (pdf)
    Fulltext
  • Kindström Andersson, Karl
    Linköping University, Department of Management and Engineering, Fluid and Mechatronic Systems. Linköping University, Faculty of Science & Engineering.
    CHAMP Operational Scenario generated from OpenAI GPT-42023Data set
    Abstract [en]

    OpenAI GPT-4 was used to generate a hypothetical scenario for the development of a hypothetical new multi-role airlift. A dataset containing the conversation leading up to this document is available under "Conversation history from Scenario Generation with OpenAI GPT-4"

    Download full text (pdf)
    CHAMP Operational Scenario generated from OpenAI GPT-4
  • Kindström Andersson, Karl
    Linköping University, Department of Management and Engineering, Fluid and Mechatronic Systems. Linköping University, Faculty of Science & Engineering.
    Conversation history from Scenario Generation with OpenAI GPT-42023Data set
    Abstract [en]

    This dataset contains the conversation history where OpenAI GPT-4 is asked to generate a hypothetical scenario for the development of a new hypothetical multi-role tactical airlift. The dataset contains all user input and the OpenAI GPT-4 output, including the graphical representations of the ontology. The generated word-file, containing the generated scenario, is stored in a separate dataset: "CHAMP Operational Scenario generated from OpenAI GPT-4"

    Download full text (pdf)
    Conversation history from Scenario Generation with OpenAI GPT-4
  • Thörnros, Edvard
    Linköping University, Department of Electrical Engineering.
    Wordlength inference in the Spade HDL: Seven implementations of wordlength inference and one implementation that actually works2023Independent thesis Advanced level (degree of Master (Two Years)), 28 HE creditsStudent thesis
    Abstract [en]

    Compilers, complex programs with the potential to greatly facilitate software and hardware design. This thesis focuses on enhancing the Spade hardware description language, known for its user-friendly approach to hardware design. In the realm of hardware development data size - for numerical values data size is known as "wordlength" - plays a critical role for reducing the hardware resources. This study presents an innovative approach that seamlessly integrates wordlength inference directly into the Spade language, enabling the over-estimation of numeric data sizes solely from the program's source code.

    The methodology involves iterative development, incorporating various smaller implementations and evaluations, reminiscent of an agile approach. To assess the efficacy of the wordlength inference, multiple place and route operations are performed on identical Spade code using various versions of nextpnr. Surprisingly, no discernible impact on hardware resource utilization emerges from the modifications introduced in this thesis.

    Nonetheless, the true significance of this endeavor lies in its potential to unlock more advanced language features within the Spade compiler. It is important to note that while the wordlength inference proposed in this thesis shows promise, it necessitates further integration efforts to realize its full potential.

    Download full text (pdf)
    wordlength-inference-in-the-spade-hdl.pdf
  • Ingemarsson, Ingemar
    Linköping University, Department of Electrical Engineering. Linköping University, The Institute of Technology.
    Informationskompetens som grunden för individuell kunskap vid självstyrt lärande1997Report (Other academic)
    Download full text (pdf)
    fulltext
  • Chowdhury, Susmita
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Hjort, Victor
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Shu, Rui
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Greczynski, Grzegorz
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Le Febvrier, Arnaud
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Eklund, Per
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Magnuson, Martin
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Thermoelectric properties and electronic structure of Cr(Mo,V)Nx thin films studied by synchrotron and lab-based x-ray spectroscopy2023In: Physical Review B, ISSN 2469-9950, E-ISSN 2469-9969, Vol. 108, no 20, article id 205134Article in journal (Refereed)
    Abstract [en]

    Chromium-based nitrides are used in hard, resilient coatings and show promise for thermoelectric applications due to their combination of structural, thermal, and electronic properties. Here, we investigate the electronic structures and chemical bonding correlated to the thermoelectric properties of epitaxially grown chromium-based multicomponent nitride Cr(Mo,V)Nx thin films. The small amount of N vacancies causes Cr 3d and N 2p states to appear at the Fermi level and reduces the band gap in Cr0.51N0.49. Incorporating holes by alloying of V in N-deficient CrN results in an enhanced thermoelectric power factor with marginal change in the charge transfer of Cr to N compared with Cr0.51N0.49. Further alloying of Mo, isoelectronic to Cr, increases the density of states at the Fermi level due to hybridization of the (Cr, V) 3d and Mo 4d-N 2p states in Cr(Mo,V)Nx. This hybridization and N off-stoichiometry result in more metal-like electrical resistivity and reduction in Seebeck coefficient. The N deficiency in Cr(Mo,V)Nx also depicts a critical role in reduction of the charge transfer from metal to N site compared with Cr0.51N0.49 and Cr0.50V0.03N0.47. In this paper, we envisage ways for enhancing thermoelectric properties through electronic band engineering by alloying and competing effects of N vacancies.

    Download full text (pdf)
    fulltext
  • Public defence: 2023-12-15 13:00 I207, LinköpingOrder onlineBuy this publication >>
    Gunnarsson, Ann-Charlotte
    Linköping University, Department of Behavioural Sciences and Learning, Education and Adult Learning. Linköping University, Faculty of Educational Sciences.
    Vuxeneleven i fokus: Att utforma metoder för individanpassad undervisning i en forskningscirkel vid Komvux2023Licentiate thesis, monograph (Other academic)
    Abstract [en]

    This study belongs to the research tradition Participatory Action Research (PAR) in the form of a Research Circle. The task was to describe and analyse the process and content of knowledge development within a Research Circle. The participants in this circle were nine teacher who work at komvux, and teach adult students in subject such as SFI, SVA and English. In this circle with participating teachers, issues of individually adapted teaching in adult education have been in focus. In this circle, empirical data has been highlighted by having the participants tell life stories and in group interviews about the individualized teaching. In an interaction between the participants´ experiences of individually adapted teaching and previous research in this area, we in the circle developed methods for individually adapted teaching in adult education. The participants tried these methods in their teaching. The methods that were developed for individually adapted teaching were both broadly and comprehensive designed, which was positive because then the teacher can adapt the teaching methods to each student group and individual adult student. The result indicate that the individually adapted teaching needs to be designed based on individual teaching, one to one teaching between teacher and adult student. Then the adult student can receive individual support in their studies and receive tasks that are individually adapted to the student´s ability to study. It is also important that the teaching is designed based on relational teaching, were the adult student both meets the teacher and other students during the course of study. This means different working methods in teaching that are individually adapted based on relational teaching. Relational teaching is especially important in language teaching. It has also been highlighted methods for individually adapted teaching based on digital teaching which is both based on individual teaching and relational teaching. This digital teaching is based on different working methods that are highlighted in this study. 

    Download full text (pdf)
    fulltext
    Download (png)
    presentationsbild
  • Public defence: 2023-12-15 13:15 ACAS, LinköpingOrder onlineBuy this publication >>
    Sommar, Carl-Johan
    Linköping University, Department of Management and Engineering, Political Science. Linköping University, Faculty of Arts and Sciences.
    Inramningar av lömska problem: Fallstudier av lokala förvaltningars möte med hållbarhet i sjukvård och under pandemin2023Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Everything should come together, and everything should permeate everything. Trends in governance and policy areas have come to encompass increasingly broader and more diverse issues. For example, sustainable development should guide all parts of government, but there is often little guidance on what this means in practice and how organizations should tackle the diverse issues and challenges of sustainability. Overall, much indicates that the challenges and problems faced by decision-makers in public administration have become increasingly difficult to manage. Some of these problems are particularly challenging and cannot be solved with a short term solution, by a single actor, or by an established method. These problems can only be managed and are referred to as "wicked problems" in the literature.

    The dissertation focuses on two wicked problems: sustainability and a pandemic. The analysis address how these wicked problems are handled by local public authorities in Sweden. Both problems have an unclear scope, a vague definition, and no definitive solution within reach. The overshadowing argument is that wicked problems need to be framed to be managed through policy mechanisms and implementation processes. The thesis argues that a frame determines and delimits the issue at hand, thus configuring what becomes manageable or not in practice.

    The dissertation is based on a selection of empirical case studies aimed at observing how governments translate the problems they face by handling both the need to become more sustainable and balancing the needs during a pandemic through changes and modifying the discourse. The study employs an interpretive and constructivist analysis of document studies and interviews with key stakeholders.

    The overarching conclusions indicate that framing is a central process necessary to move wicked problems forward on the political agenda and make them manageable. In this way, framing helps to delimit the problems; the framing becomes crucial for what becomes manageable and what is left out. Frames have different characteristics, which then influence how the problem is addressed. The conclusions suggest a continued need to make the wickedness of policy problems visible, to consider the larger and more complex aspects of certain political issues, and to strive to identify different mechanisms for managing them. We can see that framing is not just about coping with wicked issues but also about redefining the understanding of wicked problems to align more closely with an organization's limitations and possibilities. Framing offers the possibility to bridge, merge, or even transform our understanding of the wicked problem through the social reality of the organization.

    List of papers
    1. Regional Strategies for Sustainable Healthcare The Winding Ways from UN SDGs into Swedish Regional Healthcare Systems
    Open this publication in new window or tab >>Regional Strategies for Sustainable Healthcare The Winding Ways from UN SDGs into Swedish Regional Healthcare Systems
    2022 (English)In: International Journal of Public Policy, ISSN 1740-0600, E-ISSN 1740-0619, Vol. 16, no 2-4, p. 187-203Article in journal (Refereed) Published
    Abstract [en]

    Sustainable development has been defined by 17 UN goals, with the third goal (SDG3) focusing on a universal healthcare system that ensures healthy lives and wellbeing. To implement these ambitions, the goal needs to fit a regional setting before it can achieve and support healthy lives and wellbeing amongst the population. This article analyses how four Swedish regions incorporate SDG target 3.4 on non-communicable diseases and mental health into their respective healthcare organisations. The comparative analysis applies the lens of normative institutional theory to policy documents and interviews. All the regions recognise SDG3.4 by acknowledging the need for health promotion. The results show a general absence of similarities in organisational practices and policy outcomes, which is explained by region-specific factors and a lack of governmental coordination. The analysis shows that local policy core values and the related logic of appropriateness predict local outcomes of implementation of general global policies.

    Place, publisher, year, edition, pages
    InderScience Publishers, 2022
    Keywords
    Normative Institutionalism; UN Sustainable Development Goals; SDG; Regional Healthcare; Localization; Sustainable health care; Local Government.
    National Category
    Political Science
    Identifiers
    urn:nbn:se:liu:diva-186691 (URN)10.1504/IJPP.2022.124780 (DOI)
    Available from: 2022-06-30 Created: 2022-06-30 Last updated: 2023-11-17
    2. Urban food security during COVID-19: The limits of statutory welfare and the role of community action in Sweden and Korea
    Open this publication in new window or tab >>Urban food security during COVID-19: The limits of statutory welfare and the role of community action in Sweden and Korea
    2022 (English)In: Urban Governance, ISSN 2664-3286, Vol. 2, no 2, p. 328-335Article in journal (Refereed) Published
    Abstract [en]

    During COVID-19, the demand for food relief exploded as vulnerable people were suddenly more numerous and visible than ever, for which statutory welfare was not ready to cope with. We examine the role of voluntary and community organizations (VCOs) in food relief in Stockholm, Sweden and Seoul, Korea. Interpretive analysis of interview materials reveals how VCOs perceive their role vis-à-vis the state and take actions against urban food insecurity during the pandemic. The limits of statutory welfare in reaching out to vulnerable individuals reserve an indispensable role for community action in food relief even with the well-developed welfare state. Despite starkly different welfare state contexts, VCOs in both cases complement statutory welfare by swiftly identifying the risk of hunger and organizing community actions to meet the emergent needs. Given that Sweden and Korea represent the least likely cases to observe welfare provision by VCOs, the findings may have implications to general understanding of VCOs as indispensable welfare provider.

    Place, publisher, year, edition, pages
    Elsevier, 2022
    Keywords
    Urban food security, COVID-19, Non-state welfare, Voluntary and community organizations, Sweden, Korea
    National Category
    Political Science (excluding Public Administration Studies and Globalisation Studies)
    Identifiers
    urn:nbn:se:liu:diva-185980 (URN)10.1016/j.ugj.2022.06.001 (DOI)
    Funder
    Swedish Research Council Formas
    Available from: 2022-06-16 Created: 2022-06-16 Last updated: 2023-11-17Bibliographically approved
    Download full text (pdf)
    fulltext
    Download (png)
    presentationsbild
  • Kindström Andersson, Karl
    Linköping University, Department of Management and Engineering, Fluid and Mechatronic Systems. Linköping University, Faculty of Science & Engineering.
    Conversation history from scenario ontology generation with OpenAI GPT-42023Data set
    Abstract [en]

    This dataset contains the conversation history where OpenAI GPT-4 is asked to analyze a text, is asked to create an ontology and then visualize it in a graph. The dataset contains all user input and the OpenAI GPT-4 output, including the graphical representations of the ontology. The dataset also contains a JSON file that was generated that describes the ontology.

    Download full text (pdf)
    Conversation history from scenario ontology generation with OpenAI GPT-4
  • Brodow, Ragnar
    Linköping University, Department of Management and Engineering, Malmstens Linköping University.
    Mycelium + Wood = <3: How can I reduce the CO2 impact of a chair?2023Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    The primary objective of this study is to examine the viability of developing a chair with a significantly reduced carbon footprint. The research explores two distinct approaches for achieving minimal material usage in the construction process: one involving a minimal amount of wood, and the other utilizing solely wooden waste. By employing the technique of steam bending, a robust, lightweight, and durable structure can be achieved. Additionally, by harnessing the binding properties of mycelium, waste wood materials can be molded together to form a solid composite. This thesis will document the design process of two chairs that employ these two methods.

    Download full text (pdf)
    Mycelium + Wood = <3
  • Public defence: 2023-12-15 13:00 BL32, B-building, LinköpingOrder onlineBuy this publication >>
    Åkesson, Julia
    Linköping University, Department of Physics, Chemistry and Biology, Bioinformatics. Linköping University, Faculty of Science & Engineering.
    Network-based biomarker discovery for multiple sclerosis2023Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Complex autoimmune diseases, such as multiple sclerosis (MS), develop as a result of perturbations in the regulatory system controlling the function of immune cells. The disease course of MS is heterogeneous but is characterised by chronic inflammation in the central nervous system causing neurodegeneration resulting in gradual disability worsening. Disease biomarkers which are present at early stages of a disease can help clinicians to tailor treatment strategies to the expected disease course of individual persons. Gene products, i.e. RNA and proteins, serve as promising disease biomarkers due to the possibility to detect changes in abundance at early stages of a disease. Putative biomarkers can be identified by modelling different levels of gene regulation from high-throughput measurements of gene product abundance. Extracting information of disease relevance from high-throughput data is a complex problem which requires the use of efficient and targeted computational algorithms. 

    The aim of this thesis was to develop and refine methods for identifying key biomarkers involved in the development and progression of complex diseases, with the main focus on MS. In Paper I, we used a machine learning approach to identify a combination of protein biomarkers, present in the cerebrospinal fluid, which could predict the disease trajectory of persons in the early stages of MS. The abundance of proteins is a result of an intricate network of multiple regulatory factors controlling the expression of genes. A large part of the expression of genes is controlled by a few key regulators, which are believed to be crucial for the development of diseases. In addition, disease-associated genes are believed to colocalise in these networks forming so called disease modules. In Paper II, we developed a method, named ComHub, for extracting the key regulators of gene expression. In Paper III, we combined ComHub with the tool MODifieR, for disease module predictions, in a network analysis pipeline for identifying a limited set of disease-associated genes. Using this network analysis pipeline we identified a set of MS-associated genes, as well as a promising key regulator of MS. 

    The work performed in this doctoral thesis covers development of new and refined methods for modelling complex diseases, while simultaneously utilising these methods to identify disease biomarkers important for the development and progression of MS. The identified biomarkers can be used for understanding the pathology of MS, as candidate drug targets, and as promising biomarkers to aid clinicians in tailoring treatment strategies to individual persons. 

    List of papers
    1. Proteomics reveal biomarkers for diagnosis, disease activity and long-term disability outcomes in multiple sclerosis
    Open this publication in new window or tab >>Proteomics reveal biomarkers for diagnosis, disease activity and long-term disability outcomes in multiple sclerosis
    Show others...
    2023 (English)In: Nature Communications, E-ISSN 2041-1723, Vol. 14, no 1Article in journal (Refereed) Published
    Abstract [en]

    Sensitive and reliable protein biomarkers are needed to predict disease trajectory and personalize treatment strategies for multiple sclerosis (MS). Here, we use the highly sensitive proximity-extension assay combined with next-generation sequencing (Olink Explore) to quantify 1463 proteins in cerebrospinal fluid (CSF) and plasma from 143 people with early-stage MS and 43 healthy controls. With longitudinally followed discovery and replication cohorts, we identify CSF proteins that consistently predicted both short- and long-term disease progression. Lower levels of neurofilament light chain (NfL) in CSF is superior in predicting the absence of disease activity two years after sampling (replication AUC = 0.77) compared to all other tested proteins. Importantly, we also identify a combination of 11 CSF proteins (CXCL13, LTA, FCN2, ICAM3, LY9, SLAMF7, TYMP, CHI3L1, FYB1, TNFRSF1B and NfL) that predict the severity of disability worsening according to the normalized age-related MS severity score (replication AUC = 0.90). The identification of these proteins may help elucidate pathogenetic processes and might aid decisions on treatment strategies for persons with MS.

    National Category
    Neurosciences
    Identifiers
    urn:nbn:se:liu:diva-199196 (URN)10.1038/s41467-023-42682-9 (DOI)
    Note

    Funding: The study was funded by the Swedish Foundation for Strategic Research (SB16-0011 [M.G., J.E.]), the Swedish Brain Foundation, Knut and Alice Wallenberg Foundation, and Margareth AF Ugglas Foundation, Swedish Research Council (2019-04193 [M.G.], 2018-02776 [J.E.], 2020-02700 [F.P.], 2020-00014 [Z.L.P.], 2021-03092 [J.E.]), the Medical Research Council of Southeast Sweden (FORSS-315121 [J.E.]), NEURO Sweden (F2018-0052 [J.E.]), ALF grants, Region Östergötland, the Swedish Foundation for MS Research and the European Union’s Marie Sklodowska-Curie (813863 [J.E.]). The authors would like to acknowledge support of the Clinical biomarker facility at SciLifeLab Sweden for providing assistance in protein analyses.

    Available from: 2023-11-16 Created: 2023-11-16 Last updated: 2023-11-16Bibliographically approved
    2. ComHub: Community predictions of hubs in gene regulatory networks
    Open this publication in new window or tab >>ComHub: Community predictions of hubs in gene regulatory networks
    2021 (English)In: BMC Bioinformatics, ISSN 1471-2105, E-ISSN 1471-2105, Vol. 22, no 1, article id 58Article in journal (Refereed) Published
    Abstract [en]

    BackgroundHub transcription factors, regulating many target genes in gene regulatory networks (GRNs), play important roles as disease regulators and potential drug targets. However, while numerous methods have been developed to predict individual regulator-gene interactions from gene expression data, few methods focus on inferring these hubs.ResultsWe have developed ComHub, a tool to predict hubs in GRNs. ComHub makes a community prediction of hubs by averaging over predictions by a compendium of network inference methods. Benchmarking ComHub against the DREAM5 challenge data and two independent gene expression datasets showed a robust performance of ComHub over all datasets.ConclusionsIn contrast to other evaluated methods, ComHub consistently scored among the top performing methods on data from different sources. Lastly, we implemented ComHub to work with both predefined networks and to perform stand-alone network inference, which will make the method generally applicable.

    Place, publisher, year, edition, pages
    BMC, 2021
    Keywords
    Gene regulatory networks; Hubs; Master regulators; Network inference
    National Category
    Bioinformatics and Systems Biology
    Identifiers
    urn:nbn:se:liu:diva-173860 (URN)10.1186/s12859-021-03987-y (DOI)000617736000001 ()33563211 (PubMedID)
    Note

    Funding Agencies|University of Skovde; Center for Industrial IT (CENIIT); KK-stiftelsen; Swedish Research CouncilSwedish Research CouncilEuropean Commission [2015-03807]

    Available from: 2021-03-09 Created: 2021-03-09 Last updated: 2023-11-16
    3. MODalyseR—a novel software for inference of disease module hub regulators identified a putative multiple sclerosis regulator supported by independent eQTL data
    Open this publication in new window or tab >>MODalyseR—a novel software for inference of disease module hub regulators identified a putative multiple sclerosis regulator supported by independent eQTL data
    Show others...
    2022 (English)In: Bioinformatics Advances, ISSN 2635-0041, Vol. 2, no 1Article in journal (Refereed) Published
    Abstract [en]

    Network-based disease modules have proven to be a powerful concept for extracting knowledge about disease mechanisms, predicting for example disease risk factors and side effects of treatments. Plenty of tools exist for the purpose of module inference, but less effort has been put on simultaneously utilizing knowledge about regulatory mechanisms for predicting disease module hub regulators.We developed MODalyseR, a novel software for identifying disease module regulators and reducing modules to the most disease-associated genes. This pipeline integrates and extends previously published software packages MODifieR and ComHub and hereby provides a user-friendly network medicine framework combining the concepts of disease modules and hub regulators for precise disease gene identification from transcriptomics data. To demonstrate the usability of the tool, we designed a case study for multiple sclerosis that revealed IKZF1 as a promising hub regulator, which was supported by independent ChIP-seq data.MODalyseR is available as a Docker image at https://hub.docker.com/r/ddeweerd/modalyser with user guide and installation instructions found at https://gustafsson-lab.gitlab.io/MODalyseR/.Supplementary data are available at Bioinformatics Advances online.

    Place, publisher, year, edition, pages
    Oxford University Press, 2022
    National Category
    Bioinformatics and Systems Biology
    Identifiers
    urn:nbn:se:liu:diva-191117 (URN)10.1093/bioadv/vbac006 (DOI)
    Note

    Funding agencies: This work was supported by the Knowledge Foundation [dnr HSK219/26]; Swedish Foundation for Strategic Research [SB16-0011]; and Swedish Research Council [grant 2019-04193].

    Available from: 2023-01-19 Created: 2023-01-19 Last updated: 2023-11-16Bibliographically approved
    Download full text (pdf)
    fulltext
    Download (png)
    presentationsbild
  • Åkesson, Julia
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Bioinformatics. Linköping University, Faculty of Science & Engineering. Systems Biology Research Centre, School of Bioscience, University of Skövde, Skövde, Sweden.
    Hojjati, Sara
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Inflammation and Infection. Linköping University, Faculty of Medicine and Health Sciences.
    Hellberg, Sandra
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Inflammation and Infection. Linköping University, Faculty of Medicine and Health Sciences.
    Raffetseder, Johanna
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Inflammation and Infection. Linköping University, Faculty of Medicine and Health Sciences.
    Khademi, Mohsen
    Neuroimmunology Unit, Department of Clinical Neuroscience, Center for Molecular Medicine, Karolinska University Hospital, Karolinska Institute, Stockholm, Sweden.
    Rynkowski, Robert
    Linköping University, Department of Biomedical and Clinical Sciences. Linköping University, Faculty of Medicine and Health Sciences.
    Kockum, Ingrid
    Neuroimmunology Unit, Department of Clinical Neuroscience, Center for Molecular Medicine, Karolinska University Hospital, Karolinska Institute, Stockholm, Sweden.
    Altafini, Claudio
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, Faculty of Science & Engineering.
    Lubovac-Pilav, Zelmina
    Systems Biology Research Centre, School of Bioscience, University of Skövde, Skövde, Sweden.
    Mellergård, Johan
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Neurobiology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Neurologiska kliniken i Linköping.
    Jenmalm, Maria
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Inflammation and Infection. Linköping University, Faculty of Medicine and Health Sciences.
    Piehl, Fredrik
    Neuroimmunology Unit, Department of Clinical Neuroscience, Center for Molecular Medicine, Karolinska University Hospital, Karolinska Institute, Stockholm, Sweden.
    Olsson, Tomas
    Neuroimmunology Unit, Department of Clinical Neuroscience, Center for Molecular Medicine, Karolinska University Hospital, Karolinska Institute, Stockholm, Sweden.
    Ernerudh, Jan
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Inflammation and Infection. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Immunology and Transfusion Medicine.
    Gustafsson, Mika
    Linköping University, Department of Physics, Chemistry and Biology, Bioinformatics. Linköping University, Faculty of Science & Engineering.
    Proteomics reveal biomarkers for diagnosis, disease activity and long-term disability outcomes in multiple sclerosis2023In: Nature Communications, E-ISSN 2041-1723, Vol. 14, no 1Article in journal (Refereed)
    Abstract [en]

    Sensitive and reliable protein biomarkers are needed to predict disease trajectory and personalize treatment strategies for multiple sclerosis (MS). Here, we use the highly sensitive proximity-extension assay combined with next-generation sequencing (Olink Explore) to quantify 1463 proteins in cerebrospinal fluid (CSF) and plasma from 143 people with early-stage MS and 43 healthy controls. With longitudinally followed discovery and replication cohorts, we identify CSF proteins that consistently predicted both short- and long-term disease progression. Lower levels of neurofilament light chain (NfL) in CSF is superior in predicting the absence of disease activity two years after sampling (replication AUC = 0.77) compared to all other tested proteins. Importantly, we also identify a combination of 11 CSF proteins (CXCL13, LTA, FCN2, ICAM3, LY9, SLAMF7, TYMP, CHI3L1, FYB1, TNFRSF1B and NfL) that predict the severity of disability worsening according to the normalized age-related MS severity score (replication AUC = 0.90). The identification of these proteins may help elucidate pathogenetic processes and might aid decisions on treatment strategies for persons with MS.

    Download full text (pdf)
    fulltext
  • Public defence: 2023-12-19 13:00 Hugo Theorell, Building 448, LinköpingOrder onlineBuy this publication >>
    Al-Hawasi, Abbas
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Sensory Organs and Communication. Linköping University, Faculty of Medicine and Health Sciences.
    Retinal ganglion cell examination with Optical Coherence Tomography reflects physiological and pathological changes in the eye and the brain.2023Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The retinal ganglion cell is situated in the inner retina and its axons, composing the retinal nerve fiber layer (RNFL), leave the eye to form the optic nerve. These cells develop embryologically from the forebrain and later during development re-establish connections with different parts of the brain serving different purposes. This unique position and connections make it possible to be investigated with different methods. Optical Coherence Tomography (OCT) is an accessible and easily operated clinical device that can provide a detailed image of this layer at a few micrometers level of precision in measurements. In this thesis we aimed to see whether examining these cells with OCT could reflect physiological and pathological changes in the eye and brain.

    In cases of optic neuritis (Paper I), the OCT examination showed early thickening of the peripapillary (pRNFL) followed by thinning which takes 6-9 months to reduce to below normal thickness without the ability to distinguish between the real from pseudo thinning. The ganglion cell -inner plexiform layer (GCL-IPL) layer, however, showed a thickness reduction within a few weeks to 3 months without pseudo thinning.         

    In cases of Idiopathic Intracranial Hypertension (IIH) (Paper II), the GCL-IPL remained unchanged and there was no difference in pRNFL thickness compared to healthy controls, whereas  the optic disc parameters of rim thickness, rim area, cup volume and cup/disc ratio differed significantly (P<0.05).

    In cases of benign multiple sclerosis (Paper IV), the OCT could detect that eyes which are not affected by optic neuritis had an annual thinning rate of the RNFL and GCL-IPL similar to a healthy population (P>0.05) which may indicate the benign course of the disease.       

    In cases of physiological factors affecting the GCL in healthy population (Paper III) the OCT examination showed that there was a significant thinning rate of the layer with age (P<0.05), but the thinning was not significant when sex and axial length of the eye were taken into consideration. Males had a thicker GCL volume than females and with age a significant reduction in GCL volume was noted in females but not in males. A Longer axial length of the eye found to be associated with thinner GCL volume.     

    In conclusion retinal ganglion cell changes detected with OCT can reflect physiological and pathological changes in the eye and brain.   

    List of papers
    1. Acute optic neuritis: retinal ganglion cell loss precedes retinal nerve fiber thinning.
    Open this publication in new window or tab >>Acute optic neuritis: retinal ganglion cell loss precedes retinal nerve fiber thinning.
    2015 (English)In: Neurological Sciences, ISSN 1590-1874, E-ISSN 1590-3478, Vol. 36, no 4, p. 617-620Article in journal (Refereed) Published
    Abstract [en]

    Optic neuritis (ON) causes axonal loss as reflected by thinning of retinal nerve fiber layer (RNFL) and can be tracked by optical coherence tomography (OCT) about 6 months after ON onset, when swelling of optic nerve head (ONH) has vanished. Changes of macular ganglion cell layer (GCL) thickness provide another window to track the disease process in ON. GCL thinning over time in relation to RNFL change after ON remains elusive. Using OCT, we followed 4 patients with acute unilateral isolated ON for more than 9 months. A diagnosis of multiple sclerosis (MS) was established in all 4 patients. First follow-up was 2-3 weeks after ON onset, and thereafter every 2-3 months. RNFL swelling peaked during first month after acute ON, followed by rapidly reduced swelling (pseudoatrophy) during following 2 months, and thereafter successively vanished 6 months after ON onset. GCL thinning was observed 1-3 months after ON onset, i.e. already during optic disk swelling and before real RNFL thinning. The results imply that quantifying GCL thickness provides opportunities to monitor early axonal loss and ON-to-MS progression, and facilitates distinguishing real atrophy from pseudoatrophy of RNFL after acute ON.

    National Category
    Ophthalmology
    Identifiers
    urn:nbn:se:liu:diva-117096 (URN)10.1007/s10072-014-1982-3 (DOI)000351612200017 ()25311917 (PubMedID)
    Available from: 2015-04-15 Created: 2015-04-15 Last updated: 2023-11-16
    2. OCT measurements of optic nerve head changes in idiopathic intracranial hypertension
    Open this publication in new window or tab >>OCT measurements of optic nerve head changes in idiopathic intracranial hypertension
    2015 (English)In: Clinical neurology and neurosurgery (Dutch-Flemish ed. Print), ISSN 0303-8467, E-ISSN 1872-6968, Vol. 130, p. 122-127Article in journal (Refereed) Published
    Abstract [en]

    Objective: Severity of papilledema and vision loss constitute a basis for therapeutic intervention in idiopathic intracranial hypertension (IIH), but both are often subjective and insensitive in guiding clinical management. The aim of this study was to identify reliable and sensitive measurements of optic nerve head (ONH) and macula, to provide objective guidance for prognostic evaluation and treatment in IIH. We analyzed potential of spectral domain optical coherence tomography (SD-OCT), to measure neuro-retinal rim thickness and area, optic cup-to-disc ratio (C/D) and cup volume of ONH which have not previously been reported in IIH. In parallel, thickness of peripapillary retinal nerve fiber layer (RNFL) and macular ganglion cell layer (GCL) together with inner plexiform layer (IPL) (GCL-IPL) were examined. Results: All 7 enrolled IIH patients had increased neuro-retinal rim thickness (p less than 0.01 for both eyes) and rim area (p less than 0.05), decreased C/D (p less than 0.01) and optic cup volume (p less than 0.01) when compared to findings in 18 sex- and age-matched healthy controls (HC). In a longitudinal study, two IIH patients were followed repetitively by SD-OCT before and after measurement of intracranial pressure (ICP) and removal of cerebrospinal fluid (CSF) by lumbar puncture. Rim thickness and area, C/D and optic cup volume remained altered. RNFL thickness may change with very high ICP, but not immediately after CSF removal. GCL-IPL thickness was unchanged irrespective of ICP change or CSF removal. Conclusion: SD-OCT allows detection of ONH changes even in subtle IIH without papilledema and has potential for routine use in IIH.

    Place, publisher, year, edition, pages
    Elsevier, 2015
    Keywords
    Cerebrospinal fluid; Idiopathic intracranial hypertension; Optic nerve head; Optical coherence tomography; Papilledema
    National Category
    Ophthalmology
    Identifiers
    urn:nbn:se:liu:diva-116821 (URN)10.1016/j.clineuro.2014.12.021 (DOI)000350186200024 ()25614195 (PubMedID)
    Note

    Funding Agencies|County Council of Ostergotland, Sweden [LIO-121641, LiO-207242, LIO-276241]; Linkoping University

    Available from: 2015-04-07 Created: 2015-04-07 Last updated: 2023-11-16
    3. Retinal ganglion cell layer thickness and volume measured by OCT changes with age, sex, and axial length in a healthy population
    Open this publication in new window or tab >>Retinal ganglion cell layer thickness and volume measured by OCT changes with age, sex, and axial length in a healthy population
    2022 (English)In: BMC Ophthalmology, ISSN 1471-2415, E-ISSN 1471-2415, Vol. 22, no 1, article id 278Article in journal (Refereed) Published
    Abstract [en]

    Background The ganglion cell layer (GCL) measurements with Optical Coherence Tomography (OCT) are important for both ophthalmologists and neurologists because of their association with many ophthalmic and neurological diseases. Different factors can affect these measurements, such as brain pathologies, ocular axial length (AL) as well as age and sex. Studies conducted to measure the GCL have overlooked many of these factors. The purpose of this study is to examine the effect of age, sex, and AL on normal retinal GCL thickness and volume in a healthy population without any neurological diseases. Methods A prospective cross-sectional study was designed to measure GCL thickness and total volume with OCT with automated segmentation and manual correction where needed. Visual acuity, AL, and autorefraction were also measured. A mixed linear model was used to determine the association of the effect of the various parameters on the GCL thickness and volume. Results One hundred and sixteen eyes of 60 subjects (12-76 years of age, 55% female) were examined of which 77% had 0 +/- 2 D of spherical equivalent, and mean axial length was 23.86 mm. About 25% of the OCT-automated GCL measurements required manual correction. GCL thickness did not differ in similar anatomic regions in right and left eyes (P &gt; 0.05). GCL volume was greater in males relative to females after adjustment for age and axial length (1.13 +/- 0.07 mm(3) for males vs 1.09 +/- 0.09 mm(3) for females; P = 0.031). GCL thickness differed between males and females in the inner retinal ring (P = 0.025) but not in the outer ring (P = 0.66). GCL volume declined with age (P = 0.031) but not after adjustment for sex and axial length (P = 0.138). GCL volume declined with longer axial length after adjustment for age and sex (P = 0.048). Conclusion Age, sex and axial length should be taken into consideration when measuring the GCL thickness and volume with OCT. Automated OCT segmentation should be reviewed for manual adjustments.

    Place, publisher, year, edition, pages
    BMC, 2022
    Keywords
    Ganglion cell layer (GCL); Retinal ganglion cell layer (RGCL); Ganglion cell layer thickness (GCLT); Optical coherence tomography (OCT); Ganglion cell volume (GCV)
    National Category
    Ophthalmology
    Identifiers
    urn:nbn:se:liu:diva-186815 (URN)10.1186/s12886-022-02488-7 (DOI)000815497900004 ()35751115 (PubMedID)
    Note

    Funding Agencies|Linkoping University

    Available from: 2022-07-04 Created: 2022-07-04 Last updated: 2023-11-16
    4. Longitudinal Optical Coherence Tomography Measurement of Retinal Ganglion Cell and Nerve Fiber Layer to Assess Benign Course in Multiple Sclerosis
    Open this publication in new window or tab >>Longitudinal Optical Coherence Tomography Measurement of Retinal Ganglion Cell and Nerve Fiber Layer to Assess Benign Course in Multiple Sclerosis
    2023 (English)In: Journal of Clinical Medicine, E-ISSN 2077-0383, Vol. 12, no 6, article id 2240Article in journal (Refereed) Published
    Abstract [en]

    A benign form of multiple sclerosis (BMS) is not easily diagnosed, but changes of the retinal ganglion cell layer-inner plexiform layer (GCL-IPL) and retinal nerve fiber layer (RNFL) may be sensitive to the disease. The aim of this study was to use optical coherence tomography (OCT) to investigate longitudinal changes of GCL-IPL and RNFL in BMS. Eighteen patients with BMS and 22 healthy control (HC) subjects were included, with a mean follow-up period of 32.1 months in BMS and 34.3 months in HC. Mean disease duration in BMS was 23.3 years, with 14 patients left untreated. Unilateral optic neuritis (ON) was found in eight patients. Non-ON eyes showed thinner GCL-IPL layer in the BMS group relative to HC (p &lt; 0.001). The thinning rate of GCL-IPL in non-ON BMS, however, was -0.19 +/- 0.15 mu m/year vs. 0 +/- 0.11 mu m/year for HC (p = 0.573, age-adjusted). Thinning rate of RNFL in non-ON BMS was -0.2 +/- 0.27 mu m/year vs. -0.05 +/- 0.3 mu m/year for HC (p = 0.454, age adjusted). Conclusions: Thinning rate of the GCL-IPL and RNFL in BMS is similar to the healthy population but differs from the thinning rate in relapsing-remitting MS, presenting a non-invasive OCT-based criterion for assessing a benign course in multiple sclerosis.

    Place, publisher, year, edition, pages
    MDPI, 2023
    Keywords
    retinal ganglion cell; retinal nerve fiber layer; ganglion cell complex; multiple sclerosis; benign multiple sclerosis; optical coherence tomography; biomarker; neural biomarker
    National Category
    Ophthalmology
    Identifiers
    urn:nbn:se:liu:diva-193025 (URN)10.3390/jcm12062240 (DOI)000955333800001 ()36983241 (PubMedID)
    Available from: 2023-04-14 Created: 2023-04-14 Last updated: 2023-11-16
    Download full text (pdf)
    fulltext
    Download (png)
    presentationsbild
  • Public defence: 2023-12-15 10:00 KEY1, Key-building, LinköpingOrder onlineBuy this publication >>
    Yazdanpanah, Maziar
    Linköping University, Department of Culture and Society, Division of Language, Culture and Interaction. Linköping University, Faculty of Arts and Sciences.
    Multilingual Life in Dementia Care: Crossing Linguistic Boundaries and Cognitive Gap: Navigating Mutual Understanding2023Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This dissertation presents empirical research in the field of multilingual communication in residential homes of people living with dementia.  

    Prior research has emphasised the crucial function of a common language and culture between care workers and residents in such settings. It has been argued that a shared language is essential for fostering mutual understanding between care workers and residents with dementia. The absence of a common language can result in significant issues, such as creating misconceptions about the capabilities of multilingual residents, potentially preventing care workers from recognising the residents' communicative abilities. This can prevent residents with dementia from participating in social activities, leading to social isolation and negatively impact their well-being. This, in turn, increases costs for all parties involved, including residents, care workers, and residential homes.  

    While the significance of a shared language for mutual understanding is undeniable, it's not always feasible to match care workers and residents linguistically and culturally in a multilingual society with diverse ethnic groups. This situation prompts questions about how to achieve mutual understanding in the absence of a shared language in residential homes. This dissertation investigates how care workers and residents from various linguistic and cultural backgrounds in dementia care achieve mutual understanding during task-oriented communication, despite the absence of a shared verbal language.  

    Employing a micro-analytic perspective, this research delves deep into instances of multilingual communication within residential homes to uncover the function of linguistic features such as sound prolongation in task-oriented communication. Additionally, the study explores how forms of address contribute to achieving mutual understanding in dementia care when there's no shared verbal language in multilingual communication. These questions are addressed using data obtained through a combination of ethnography, video recordings, and interviews. The study involves participants, including residents from ethnic minorities displaying symptoms of dementia and care workers from diverse linguistic backgrounds.  

    Conversation analysis is employed for transcribing and analysing interactions among participants, while thematic analysis is applied to the interview data. The results suggest that in the absence of a common verbal language, participants recycle each other's verbal and nonverbal actions to foster mutual understanding. This process relies heavily on the actions of care workers. The findings also underscore the importance of care workers’ knowledge of residents' life histories, including their preferred forms of address, as a valuable resource for establishing rapport with residents.  

    In conclusion, this dissertation highlights that the effectiveness of specific linguistic resources in multilingual communication not only varies among individuals but is also contingent on the particular situations in which a resident is involved. 

    List of papers
    1. Accommodation Practices in Multilingual Encounters in Swedish Residential Care
    Open this publication in new window or tab >>Accommodation Practices in Multilingual Encounters in Swedish Residential Care
    2017 (English)In: Multilingual Interaction and Dementia / [ed] Plejert, Charlotta; Lindholm, Camilla; Schrauf, Robert W., Multilingual Matters , 2017, p. 148-174Chapter in book (Other academic)
    Place, publisher, year, edition, pages
    Multilingual Matters, 2017
    Series
    Communication Disorders Across Languages
    National Category
    Health Care Service and Management, Health Policy and Services and Health Economy
    Identifiers
    urn:nbn:se:liu:diva-199188 (URN)10.21832/9781783097678-009 (DOI)9781783097678 (ISBN)
    Available from: 2023-11-15 Created: 2023-11-15 Last updated: 2023-11-15
    2. An interactional perspective on sound prolongation in multilingual encounters in residential care
    Open this publication in new window or tab >>An interactional perspective on sound prolongation in multilingual encounters in residential care
    2019 (English)In: Clinical Linguistics & Phonetics, ISSN 0269-9206, E-ISSN 1464-5076, Vol. 33, no 2, p. 1103-1124Article in journal (Refereed) Published
    Abstract [en]

    Elderspeak refers to adapting ones language to a perceived language decline of an older interlocutor. Earlier studies have explored different features of elderspeak; some of these studies attribute positive outcomes to using elderspeak that facilitates communication, but other studies consider elderspeak a negative way of communicating that should be avoided. The aim of this study is to investigate a largely unexplored feature of elderspeak, namely sound prolongation in a multilingual context. There are five participants in this study: three carers and two care recipients in a residential care unit. The carers and care recipients have limited access to a shared spoken language. The data consist of video- and audio recordings of interaction between the participants. The recordings have been transcribed and analysed in accordance with Conversation Analytical methodology. The analysis shows that the carers use sound prolongation as part of their interactional repertoire in order to manage situations of distress. We conclude that in some distressful situations carers use of sound prolongation may help mitigating the care recipients emotional concerns since the source of agitations has been addressed properly. In other situations, the use of sound prolongation may lead to an escalation in distress, if the source of agitation is not addressed adequately. Our results bring to the fore that an interactional practice, such as the use of sound prolongation in the context of expressed distress must be interpreted in relation to the complexity of each and every situation participants find themselves in, their level of understanding, and the task/activity at hand.

    Place, publisher, year, edition, pages
    Taylor & Francis, 2019
    Keywords
    Sound prolongation; resistiveness to care; agitation; elderspeak; conversation analysis
    National Category
    Specific Languages
    Identifiers
    urn:nbn:se:liu:diva-159868 (URN)10.1080/02699206.2019.1584914 (DOI)000479994100001 ()31385544 (PubMedID)2-s2.0-85070825137 (Scopus ID)
    Note

    Funding Agencies|Stiftelsen Solstickan; Vetenskapsradet

    Available from: 2019-08-27 Created: 2019-08-27 Last updated: 2023-11-15Bibliographically approved
    3. Whats in a name? Address practices in Swedish residential care facilities
    Open this publication in new window or tab >>Whats in a name? Address practices in Swedish residential care facilities
    2022 (English)In: Journal of Aging Studies, ISSN 0890-4065, E-ISSN 1879-193X, Vol. 61, article id 101007Article in journal (Refereed) Published
    Abstract [en]

    Encountering residents living with dementia who come from diverse linguistic and cultural backgrounds is a common aspect of everyday life in residential care homes. These facilities may have systems of address that differ from those used in residents respective cultures of origin. Residents forms of address are elements of identity established in accordance with their life histories. The aim of this article is to investigate empirically the role of address forms for residents and care-providing staff in multilingual residential settings. The findings rely on observational and interactional data as well as interviews. The observational and interactional data includes 23 participants, consisting of five residents and 18 members of care-providing staff. The interviews consist of informal conversations and a corpus based on open-ended interviews with 21 staff members and five residents in two residential homes in Sweden. On the one hand, the findings indicate that addressing the residents with their first name is a prevalent address practice by the staff. They also displayed 20 additional types of address practices. On the other hand, these practices, which are chosen with the best of intentions, often seem to be inconsistent with the residents preferred address forms. These data lend support to the large body of gerontological literature arguing that sensitivity to the life histories of residents, here the established forms of address, is vital to sustaining their identity.

    Place, publisher, year, edition, pages
    ELSEVIER SCIENCE INC, 2022
    Keywords
    Name; Form of address; Identity; Dementia
    National Category
    Nursing
    Identifiers
    urn:nbn:se:liu:diva-192356 (URN)10.1016/j.jaging.2022.101007 (DOI)000933151900006 ()35654542 (PubMedID)
    Note

    Funding Agencies|Vetenskapsradet

    Available from: 2023-03-16 Created: 2023-03-16 Last updated: 2023-11-15
    Download full text (pdf)
    fulltext
    Download (png)
    presentationsbild
  • Langer, Marcel F.
    et al.
    Machine Learning Group, Technische Universität Berlin, Berlin, Germany; BIFOLD–Berlin Institute for the Foundations of Learning and Data, Berlin, Germany; The NOMAD Laboratory at the Fritz Haber Institute of the Max Planck Society and Humboldt University, Berlin, Germany.
    Frank, J. Thorben
    Machine Learning Group, Technische Universität Berlin, Berlin, Germany; BIFOLD–Berlin Institute for the Foundations of Learning and Data, Berlin, Germany.
    Knoop, Florian
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Physics. Linköping University, Faculty of Science & Engineering.
    Stress and heat flux via automatic differentiation2023In: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 159, no 17, article id 174105Article in journal (Refereed)
    Abstract [en]

    Machine-learning potentials provide computationally efficient and accurate approximations of the Born–Oppenheimer potential energy surface. This potential determines many materials properties and simulation techniques usually require its gradients, in particular forces and stress for molecular dynamics, and heat flux for thermal transport properties. Recently developed potentials feature high body order and can include equivariant semi-local interactions through message-passing mechanisms. Due to their complex functional forms, they rely on automatic differentiation (AD), overcoming the need for manual implementations or finite-difference schemes to evaluate gradients. This study discusses how to use AD to efficiently obtain forces, stress, and heat flux for such potentials, and provides a model-independent implementation. The method is tested on the Lennard-Jones potential, and then applied to predict cohesive properties and thermal conductivity of tin selenide using an equivariant message-passing neural network potential.

    Download full text (pdf)
    fulltext
  • Public defence: 2023-12-15 13:15 Belladonna, LinköpingOrder onlineBuy this publication >>
    Belcastro, Luigi
    Linköping University, Department of Biomedical Engineering, Division of Biomedical Engineering. Linköping University, Faculty of Science & Engineering.
    Multi-frequency SFDI: depth-resolved scattering models of wound healing2023Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    With optical techniques, we refer to a group of methods that use of light to perform measurements on matter. Spatial frequency domain imaging (SFDI) is an optical technique that operates in the spatial frequency domain. The technique involves using sinusoidal patterns of light for illumination, to study the reflectance of the target based on the spatial frequency (ƒx) of the patterns. By analysing the frequency-specific response with the aid of light transport models, we are able to determine the intrinsic optical properties of the material, such as the absorption coefficient (μa) and reduced scattering coefficient (μ's) In biological applications, these optical properties can be correlated to physiological structures and molecules, providing a useful tool for researchers and clinicians alike in understanding the phenomena happening in biological tissue. The objective of this work is to contribute to the development of SFDI, so that the technique can be used as a diagnostic tool to study the process of wound healing in tissue. In paper I we introduce the concept of cross-channels, given by the spectral overlap of the broadband LED light sources and the RGB camera sensors used in the SFDI instrumentation. The purpose of cross-channels is to improve the limited spectral information of RGB devices, allowing to detect a larger number of biological molecules. One of the biggest limitations of SFDI is that it works on the assumption of light diffusing through a homogeneous, thick layer of material. This assumption loses validity when we want to examine biological tissue, which comprises multiple thin layers with different properties. In paper IV we have developed a new method to process SFDI data that we call multi-frequency SFDI. In this new approach, we make use of the different penetration depth of the light patterns depending on their ƒx to obtain depth-sensitive measurements. We also defined a 2-layer model of light scattering that imitates the physiology of a wound, to calculate the partial volume contributions to μ's of the single layers. The 2-layer model is based on analytical formulations of light fluence. We compared the performance of three fluence models, one of which we have derived ourselves as an improvement over an existing formulation. In paper II we were able to test our new multi-frequency SFDI method by participating in an animal study on stem-cells based regenerative therapies. We contributed by performing SFDI measurements on healing wounds, in order to provide an additional evaluation metric that complemented the clinical evaluation and cell histology performed in the study. The analysis of the SFDI data at different ƒx highlighted different processes happening on the surface compared to the deeper tissue. In paper V we further refine the technique introduced in paper IV by developing an inverse solver algorithm to isolate the thickness of the thin layer and the layer-specific μ's. The reconstructed parameters were tested both on thin silicone optical phantoms and ex-vivo burn wounds treated with stem cells. 

    List of papers
    1. Handheld multispectral imager for quantitative skin assessment in low resource settings
    Open this publication in new window or tab >>Handheld multispectral imager for quantitative skin assessment in low resource settings
    2020 (English)In: Journal of Biomedical Optics, ISSN 1083-3668, E-ISSN 1560-2281, Vol. 25, no 8, article id 082702Article in journal (Refereed) Published
    Abstract [en]

    Significance: Spatial frequency domain imaging (SFDI) is a quantitative imaging method to measure absorption and scattering of tissue, from which several chromophore concentrations (e.g., oxy-/deoxy-/meth-hemoglobin, melanin, and carotenoids) can be calculated. Employing a method to extract additional spectral bands from RGB components (that we named cross-channels), we designed a handheld SFDI device to account for these pigments, using low-cost, consumer-grade components for its implementation and characterization.

    Aim: With only three broad spectral bands (red, green, blue, or RGB), consumer-grade devices are often too limited. We present a methodology to increase the number of spectral bands in SFDI devices that use RGB components without hardware modification.

    Approach: We developed a compact low-cost RGB spectral imager using a color CMOS camera and LED-based mini projector. The components’ spectral properties were characterized and additional cross-channel bands were calculated. An alternative characterization procedure was also developed that makes use of low-cost equipment, and its results were compared. The device performance was evaluated by measurements on tissue-simulating optical phantoms and in-vivo tissue. The measurements were compared with another quantitative spectroscopy method: spatial frequency domain spectroscopy (SFDS).

    Results: Out of six possible cross-channel bands, two were evaluated to be suitable for our application and were fully characterized (520  ±  20  nm; 556  ±  18  nm). The other four cross-channels presented a too low signal-to-noise ratio for this implementation. In estimating the optical properties of optical phantoms, the SFDI data have a strong linear correlation with the SFDS data (R2  =  0.987, RMSE  =  0.006 for μa, R2  =  0.994, RMSE  =  0.078 for μs′).

    Conclusions: We extracted two additional spectral bands from a commercial RGB system at no cost. There was good agreement between our device and the research-grade SFDS system. The alternative characterization procedure we have presented allowed us to measure the spectral features of the system with an accuracy comparable to standard laboratory equipment.

    Place, publisher, year, edition, pages
    SPIE - The International Society for Optics and Photonics, 2020
    Keywords
    multispectral imaging; spatial frequency domain imaging; low-resource settings; digital micromirror device; skin; phantoms
    National Category
    Medical Engineering
    Identifiers
    urn:nbn:se:liu:diva-169868 (URN)10.1117/1.JBO.25.8.082702 (DOI)000590144000002 ()32755076 (PubMedID)2-s2.0-85089133009 (Scopus ID)
    Funder
    Wallenberg Foundations
    Note

    Funding agencies:  Knut and Alice Wallenberg FoundationKnut & Alice Wallenberg Foundation

    Available from: 2020-09-22 Created: 2020-09-22 Last updated: 2023-11-14Bibliographically approved
    2. Beneath the skin: multi-frequency SFDI to detect thin layers of skin using light scattering
    Open this publication in new window or tab >>Beneath the skin: multi-frequency SFDI to detect thin layers of skin using light scattering
    Show others...
    2023 (English)In: PHOTONICS IN DERMATOLOGY AND PLASTIC SURGERY 2023, SPIE-INT SOC OPTICAL ENGINEERING , 2023, Vol. 12352, article id 1235209Conference paper, Published paper (Refereed)
    Abstract [en]

    Wound healing assessment is usually performed visually by a trained physician. This type of evaluation is very subjective and returns limited information about the wound progression. In contrast, optical imaging techniques are non-invasive ways to quantitatively measure biological parameters. Spatial frequency domain imaging (SFDI) is an optical technique that exploits sinusoidal patterns of light with multiple spatial frequencies to measure the tissue frequency-specific response, from which the absorption and scattering coefficient of the material can be derived. While SFDI is based on models of light transport that assume the tissue is homogeneous, skin is composed by several layer with very different optical properties. An underutilized property of SFDI, however, is that the spatial frequency of the patterns determines the penetration depth of photons in the tissue. By using multiple ranges of spatial frequencies, we are developing a means to obtain morphological data from different volumes of tissue. This data is used to reconstruct the optical properties in depth, allowing us to differentiate between different thin layers of tissue. In this study we have developed a 2-layer optical phantom model with realistic optical properties and dimensions, that mimics the physiology of wound healing. We have used this physical model to validate the accuracy of this approach in obtaining layer specific optical properties.

    Place, publisher, year, edition, pages
    SPIE-INT SOC OPTICAL ENGINEERING, 2023
    Series
    Progress in Biomedical Optics and Imaging, ISSN 1605-7422
    Keywords
    SFDI; light scattering; wound healing; thin layers; depth reconstruction
    National Category
    Medical Laboratory and Measurements Technologies
    Identifiers
    urn:nbn:se:liu:diva-196941 (URN)10.1117/12.2648545 (DOI)001012400300008 ()9781510658097 (ISBN)9781510658103 (ISBN)
    Conference
    Conference on Photonics in Dermatology and Plastic Surgery, San Francisco, CA, jan 28-29, 2023
    Available from: 2023-08-29 Created: 2023-08-29 Last updated: 2023-11-14
    Download full text (pdf)
    fulltext
    Download (png)
    presentationsbild
  • Public defence: 2023-12-19 09:00 Berzeliussalen, LinköpingOrder onlineBuy this publication >>
    Pizzolato, Giulia
    Linköping University, Department of Biomedical and Clinical Sciences, Division of Molecular Medicine and Virology. Linköping University, Faculty of Medicine and Health Sciences.
    Molecular characterization of FOX factors and Wnt signalling interplay in human cancers2023Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Wnt/β-catenin signalling, also referred to as canonical Wnt signalling, is a critical regulator of tissue homeostasis and of the differentiation of cells during development. The outcome of canonical Wnt pathway activity is defined by the regulation of target gene transcription, which ultimately determines cell identity and proliferation. How multiple proteins coordinate to modulate Wnt signalling in numerous tissues is an evolving question.

    Over the years, FOX transcription factors have been emerging as modulators of Wnt signalling in a variety of tissue and cell-specific contexts. Nevertheless, the function of each FOX protein in the pathway as well as their role in different pathophysiological contexts is an open matter.

    The overall aim of this thesis was to investigate two FOX family members, FOXB2 and FOXQ1, to uncover their roles in Wnt/β-catenin signalling. Additionally, in the last work, I aimed to investigate how the FOXQ1 oncogene is transcriptionally regulated in cancer.

    In the first paper, we uncovered FOXB2 as a new potent activator of Wnt signalling via the induction of agonistic Wnt ligands, particularly WNT7B. In addition, FOXB2 is induced in aggressive prostate cancer where it is associated with a neuroendocrine differentiation program and poor prognosis.

    In the second paper, we explored the molecular mechanisms used by the carcinoma oncogene FOXQ1 to drive Wnt signalling activation. Our results showed that FOXQ1 has a major role in tuning the Wnt transcriptional output and, in synergy with active Wnt signalling, converged on a transcriptional program linked to epithelial-to-mesenchymal transition (EMT) and cell migration, which has important implications for cancer biology.

    In the third paper, we reveal that p53 functions as transcriptional repressor of FOXQ1 in cancers. Loss of p53 is present in the majority of human cancers and, in synergy with activation of Wnt signalling, could boost FOXQ1 expression, thereby affecting the progression of cancer.

    Overall, this thesis provides a better understanding of the complexity of Wnt signalling on the molecular level and newly elucidates the function of these two FOX proteins as drivers of oncogenic Wnt pathway activation. Additionally, this new evidence highlights the importance of further in-depth investigation of FOX transcription factors in cancer biology. The relevant role of FOX proteins in the development and progression of cancer is increasingly evident, and in the long run, it will be valuable to characterize the role of FOX factors in a tissue-specific context for the development of targeted cancer therapies.

    List of papers
    1. Wnt activator FOXB2 drives the neuroendocrine differentiation of prostate cancer
    Open this publication in new window or tab >>Wnt activator FOXB2 drives the neuroendocrine differentiation of prostate cancer
    2019 (English)In: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 116, no 44, p. 22189-22195Article in journal (Refereed) Published
    Abstract [en]

    The Wnt signaling pathway is of paramount importance for development and disease. However, the tissue-specific regulation of Wnt pathway activity remains incompletely understood. Here we identify FOXB2, an uncharacterized forkhead box family transcription factor, as a potent activator of Wnt signaling in normal and cancer cells. Mechanistically, FOXB2 induces multiple Wnt ligands, including WNT7B, which increases TCF/LEF-dependent transcription without activating Wnt coreceptor LRP6 or beta-catenin. Proximity ligation and functional complementation assays identified several transcription regulators, including YY1, JUN, and DDX5, as cofactors required for FOXB2-dependent pathway activation. Although FOXB2 expression is limited in adults, it is induced in select cancers, particularly advanced prostate cancer. RNA-seq data analysis suggests that FOXB2/WNT7B expression in prostate cancer is associated with a transcriptional program that favors neuronal differentiation and decreases recurrence-free survival. Consistently, FOXB2 controls Wnt signaling and neuroendocrine differentiation of prostate cancer cell lines. Our results suggest that FOXB2 is a tissue-specific Wnt activator that promotes the malignant transformation of prostate cancer.

    Place, publisher, year, edition, pages
    NATL ACAD SCIENCES, 2019
    Keywords
    FOXB2; Wnt signaling; forkhead; prostate cancer
    National Category
    Cancer and Oncology
    Identifiers
    urn:nbn:se:liu:diva-162065 (URN)10.1073/pnas.1906484116 (DOI)000493720200039 ()31611391 (PubMedID)
    Note

    Funding Agencies|Knut and Alice Wallenberg FoundationKnut & Alice Wallenberg Foundation

    Available from: 2019-11-19 Created: 2019-11-19 Last updated: 2023-11-14
    2. The oncogenic transcription factor FOXQ1 is a differential regulator of Wnt target genes
    Open this publication in new window or tab >>The oncogenic transcription factor FOXQ1 is a differential regulator of Wnt target genes
    Show others...
    2022 (English)In: Journal of Cell Science, ISSN 0021-9533, E-ISSN 1477-9137, Vol. 135, no 19, article id jcs260082Article in journal (Refereed) Published
    Abstract [en]

    The forkhead box transcription factor FOXQ1 contributes to the pathogenesis of carcinomas. In colorectal cancers, FOXQ1 promotes tumour metastasis by inducing epithelial-to-mesenchymal transition (EMT) of cancer cells. FOXQ1 may exacerbate cancer by activating the oncogenic Wnt/beta-catenin signalling pathway. However, the role of FOXQ1 in the Wnt pathway remains to be resolved. Here, we report that FOXQ1 is an activator of Wnt-induced transcription and regulator of beta-catenin target gene expression. Upon Wnt pathway activation, FOXQ1 synergises with the beta-catenin nuclear complex to boost the expression of major Wnt targets. In parallel, we find that FOXQ1 controls the differential expression of various Wnt target genes in a beta-catenin-independent manner. Using RNA sequencing of colorectal cancer cell lines, we show that Wnt signalling and FOXQ1 converge on a transcriptional programme linked to EMT and cell migration. Additionally, we demonstrate that FOXQ1 occupies Wnt-responsive elements in beta-catenin target gene promoters and recruits a similar set of co-factors to the beta-catenin-associated transcription factor Tcf711. Taken together, our results indicate a multifaceted role of FOXQ1 in Wnt/beta-catenin signalling, which may drive the metastasis of colorectal cancers.

    Place, publisher, year, edition, pages
    COMPANY BIOLOGISTS LTD, 2022
    Keywords
    Colorectal cancer; Forkhead box; Gene expression; Proteomics; Wnt signalling
    National Category
    Cell Biology
    Identifiers
    urn:nbn:se:liu:diva-189563 (URN)10.1242/jcs.260082 (DOI)000877164900003 ()36124643 (PubMedID)2-s2.0-85139409180 (Scopus ID)
    Funder
    Knut and Alice Wallenberg FoundationSwedish Research Council, 2020-01084Swedish Cancer Society, 20 0737 Pj 01 HSwedish Cancer Society, CAN 2018/542Linköpings universitet
    Note

    Funding: Knut och AliceWallenbergs Stiftelse; Vetenskapsradet [2020-01084]; Cancerfonden [0737 Pj 01, CAN 2018/542]; Linkopings Universitet

    Available from: 2022-10-26 Created: 2022-10-26 Last updated: 2023-11-14Bibliographically approved
    Download full text (pdf)
    fulltext
    Download (png)
    presentationsbild
  • Public defence: 2023-12-14 10:00 TEMCAS, LinköpingOrder onlineBuy this publication >>
    Holmbom Strid, Emilia
    Linköping University, Department of Thematic Studies, Department of Child Studies. Linköping University, Faculty of Arts and Sciences.
    Laughter, excitement, and suspense in preschool: Choreographing emotional stances as a multiparty achievement2023Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Most research on emotions, including that which takes a social perspective, is directed at negative emotions and their manifestation in social situations that involve conflicts, disputes, and arguments. This thesis instead aims to address children’s heightened positive emotions and their interactional functions within the peer group and in learning encounters with teachers in preschool. Theoretically and methodologically, the thesis adopts a multimodal interaction analysis perspective. The data comprises 40 hours of video-ethnographic recordings of everyday activities conducted in a regular preschool in Sweden. The participants include 6 teachers and 50 children (ages 1-5, girls and boys). The following research questions underpin the thesis: How do young children invite co-participation and reciprocate laughter in multiparty interactions with peers and teachers? How do young children invoke excitement displays to initiate joint attention in multiparty peer settings in preschool? How do teachers choreograph suspense practices as a means to organize participation in educational activities? The thesis highlights the communicative and social affordances and challenges that young children encounter when interacting in large groups in preschool settings. The thesis contributes with knowledge in a largely unexplored area, i.e., heightened emotional displays in children’s peer groups, and adult-child interactions.

    List of papers
    1. Embodiment in reciprocal laughter: sharing laughter, gaze, and embodied stance in children’s peer group
    Open this publication in new window or tab >>Embodiment in reciprocal laughter: sharing laughter, gaze, and embodied stance in children’s peer group
    2021 (English)In: How emotions are made in talk / [ed] Jessica S. Robles, Ann Weatherall, Amsterdam: John Benjamins Publishing Company, 2021, Vol. Sidorna 163-186, p. 163-186Chapter in book (Other academic)
    Abstract [en]

    Laughter is a mundane phenomenon that is ubiquitous in social life. This chapter examines young children’s laughter, specifically focusing on the calibration of shared laughter as it typically occurs in multiparty interactions. It discusses?children’s interactional competences in calibrating emotional stances and affiliation. The analysis takes into account the multimodal features that characterise situations of reciprocal laughter, contributing to the understanding of laughter as a fully embodied social phenomenon. It shows that laughter was interactionally accomplished in ways that established affiliation between a group or a dyad of children. The establishment of mutual gaze was important in initiating, reciprocating and sustaining shared emotional stance through the performance?of laughter. The embodied calibration of the children’s shared stance shows that laughter is used in the establishment of affiliation and rapport. Young children’s situated humor and ‘funniness’ is thus clearly a joint, shared interactional and social – dyadic or multiparty – accomplishment.

    Place, publisher, year, edition, pages
    Amsterdam: John Benjamins Publishing Company, 2021
    National Category
    Psychology
    Identifiers
    urn:nbn:se:liu:diva-185212 (URN)9789027260062 (ISBN)
    Available from: 2022-05-19 Created: 2022-05-19 Last updated: 2023-11-14Bibliographically approved
    2. Calibrating joint attention and affective stances in young childrens peer interactions
    Open this publication in new window or tab >>Calibrating joint attention and affective stances in young childrens peer interactions
    2022 (English)In: Journal of Pragmatics, ISSN 0378-2166, E-ISSN 1879-1387, Vol. 198, p. 29-42Article in journal (Refereed) Published
    Abstract [en]

    The present study addresses young childrens (three-to five-year-olds) peer interactions and explores a recurrent interactional genre, i.e. childrens affectively heightened attention-organizing practices used when initiating an exchange in preschool interactions in Sweden. The data consists of 40 h of video recordings collected in two regular pre-schools in Sweden. By using Multimodal Interaction Analysis (Goodwin, 2000) of video -recordings from everyday activities, we examine the verbal, embodied and material fea-tures of childrens interactions. The analysis shows that children exploited common access to objects or physical personal attributes within their socio-material environment and relied on them to secure the others attention, while using various methods for making the object noteworthy. By indexing their affective stance towards the referent, the children created the interpretative framework for the recipients response. However, the recipients orientation and stance alignment were not to be presumed. The peer responses comprised a continuum of their affective engagement: the children aligned with or downplayed the prior speakers stance through the affective quality of their response. In all, detailed interactional analysis reveals the young childrens interactional repertoires and the communicative challenges associated with childrens peer interactions.

    Place, publisher, year, edition, pages
    Elsevier, 2022
    Keywords
    Peer group interactions; Emotion; Stance; Alignment; Attention-getting
    National Category
    Other Social Sciences not elsewhere specified
    Identifiers
    urn:nbn:se:liu:diva-187297 (URN)10.1016/j.pragma.2022.05.016 (DOI)000827250300004 ()
    Note

    Funding Agencies|Swedish Research Council [742-2013-7626]

    Available from: 2022-08-18 Created: 2022-08-18 Last updated: 2023-11-14
    Download full text (pdf)
    fulltext
    Download (png)
    presentationsbild
  • Thorstensson, Anna-Karin (Editor)
    Linköping University, Communications and Marketing Division. Linköping University, University Services.
    LiU Magasin2023Other (Other (popular science, discussion, etc.))
    Download full text (pdf)
    fulltext
    Download (png)
    presentationsbild
  • Public defence: 2023-12-15 09:00 Hasselquist, building 511, LinköpingOrder onlineBuy this publication >>
    Allemann, Hanna
    Linköping University, Department of Health, Medicine and Caring Sciences, Division of Nursing Sciences and Reproductive Health. Linköping University, Faculty of Medicine and Health Sciences.
    Online support for informal carers of persons with heart failure: Focus on perceptions, development and experiences2023Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Background: Heart failure (HF) is a common condition, and its prevalence is expected to increase. The illness trajectory is unpredictable, and its effects will include a potential impact on informal carers, i.e., family, friends, and significant others. Sometimes these persons are affected by the help and care they provide in such a way that they might themselves need support. However, they may be unrecognised in their endeavours, and might also experience a lack of support, especially from healthcare. Online solutions are considered to have the potential to provide accessible support to carers that is also anticipated to be cost-effective.   

    Aim: This thesis focuses on support to informal carers to persons living with HF, but also take the viewpoint of the person with HF by exploring social supports associations with their health and well-being. The overall aim was to explore perceptions, development, and experiences of online support for informal carers.  

    Method: This thesis comprises four studies. Study I had a cross-sectional design using self-reported data and data from the Swedish Pace-maker and ICD Registry. Data from 1,550 persons with HF who were living with an ICD and who had complete data on the outcome variable were utilised for both descriptive analysis and logistic regression. The outcome variable, perceived social support, was measured using the questionnaire Multidimensional Scale of Perceived Social Support (MSPSS), which includes measuring support from significant others, family, and friends. The logistic regression was conducted to compare those dichotomised as having low/medium perceived social support to those having high levels of support. Study II had a qualitative design, and data were collected through 8 focus groups with 23 informal carers of persons with HF to explore their perceptions of how online solutions could be of value for support. Data were analysed using qualitative content analysis. Study III had a descriptive design. It describes the co-design process of an online support pro-gramme for carers through three phases. In phase I, topics and content that reflected carers needs and preferences were identified. In phase II, the content for the support programme was developed and through phase III the content was refined and finalised. Informal carers participated in every phase, and the co-design process also involved professionals with expertise in, for example, HF and caregiving, for the development of content. It was an iterative process, moving back and forth between phases, and the re-search group acted as coordinators and ensured that carers’ voices were kept central to the process. Study IV had a qualitative design, and data were collected through individual semi-structured interviews with 15 carers. Interviews were analysed using qualitative content analysis. The study focused on informal carers' experiences of online, co-designed support pro-gramme while being participants in a randomised controlled trial (RCT) that has the aim of studying the effects of engaging with the programme.  

    Results: The findings show that one in five diagnosed with HF and living with an ICD reported low/medium levels of social support and that these persons had higher odds of negative psychosocial outcomes. This un-derscores the value and importance of support from informal carers for the well-being of those with HF. The thesis focused on perceptions, development, and experiences of online support for informal carers. The findings suggest that a co-designed support programme has the potential to be usable and useful for carers considering the online format and its content. It may provide insights, preparedness, and validation in relation to being a carer of a person with HF. However, carers may have an ‘ambiguous stance’ towards the online format and going online for support may not be the preferred form of support for all carers.   

    Conclusion: A co-designed online support programme, when built on a trusted platform within a healthcare context, may be considered both usable and useful for carers. The online format and content also provide the potential to offer timely and adaptable support. The content, developed in a collaboration between carers and professionals, offers evidence-based, relevant information, thereby possibly avoiding seeming impersonal, which can also be beneficial. The programme acknowledges the intertwined lives of carers and those with HF, and its content reflects this, potentially also enhancing its perception as usable and useful for carers. Still, the potential of the support programme depends on carers being aware of its existence, or being made aware, and can further recognise its value. The support programme is considered to have the capacity to be relevant for a broad group of carers, and therefore efforts may be of importance to ensure it is accessed and utilised. However, it is also important to take into account that not everyone may be willing or able to go online for support, or may wish to stay in a caring role. Healthcare also needs to recognise this when offering support to carers and the online support may be regarded an option among several. 

    List of papers
    1. Perceived Social Support in Persons With Heart Failure Living With an Implantable Cardioverter Defibrillator: A Cross-sectional Explorative Study
    Open this publication in new window or tab >>Perceived Social Support in Persons With Heart Failure Living With an Implantable Cardioverter Defibrillator: A Cross-sectional Explorative Study
    2018 (English)In: Journal of Cardiovascular Nursing, ISSN 0889-4655, E-ISSN 1550-5049, Vol. 33, no 6, p. E1-E8Article in journal (Refereed) Published
    Abstract [en]

    BACKGROUND: The links between chronic illness, psychological well-being, and social support have previously been established. Social isolation and loneliness have shown an increased mortality risk for those with heart failure (HF). Increasingly more people with HF are living with an implantable cardioverter defibrillator (ICD), but only a few small-scale studies have focused on social support in this population.

    OBJECTIVE: The aim of this study was to explore factors related to perceived social support in a large cohort of individuals with HF living with an ICD.

    METHODS: All eligible adult ICD recipients in the Swedish ICD registry were invited to participate in this cross-sectional study. For this analysis, those with HF and complete data on perceived social support were included (N = 1550; age, 67.3 (SD, 9.8) years; 19.5% female).

    RESULTS: Most reported a high level of social support, but 18% did not. In logistic regression, living alone was the greatest predictor of low/medium support. Lower social support for those living alone was associated with poorer perceived health status, having symptoms of depression, and experiencing low perceived control. For those living with someone, lower support was associated with female gender, symptoms of depression and anxiety, and less control. Heart failure status and perceived symptom severity were not related to the outcome.

    CONCLUSION: One in five participants reported low/medium social support. Our study underlines the complex relationships between perceived social support, psychological well-being and perceived control over the heart condition. Multiple aspects need to be taken into account when developing interventions to provide psychosocial support and optimize outcomes in this patient group.

    Place, publisher, year, edition, pages
    Lippincott Williams & Wilkins, 2018
    National Category
    Nursing
    Identifiers
    urn:nbn:se:liu:diva-154035 (URN)10.1097/JCN.0000000000000523 (DOI)000457866800001 ()30063538 (PubMedID)
    Available from: 2019-01-24 Created: 2019-01-24 Last updated: 2023-11-14
    2. Perceptions of Information and Communication Technology as Support for Family Members of Persons With Heart Failure: Qualitative Study
    Open this publication in new window or tab >>Perceptions of Information and Communication Technology as Support for Family Members of Persons With Heart Failure: Qualitative Study
    Show others...
    2019 (English)In: Journal of Medical Internet Research, ISSN 1438-8871, E-ISSN 1438-8871, Vol. 21, no 7, article id e13521Article in journal (Refereed) Published
    Abstract [en]

    Background: Heart failure (HF) affects not only the person diagnosed with the syndrome but also family members, who often have the role of informal carers. The needs of these carers are not always met, and information and communications technology (ICT) could have the potential to support them in their everyday life. However, knowledge is lacking about how family members perceive ICT and see opportunities for this technology to support them. Objective: The aim of this study was to explore the perceptions of ICT solutions as supportive aids among family members of persons with HF. Methods: A qualitative design was applied. A total of 8 focus groups, comprising 23 family members of persons affected by HF, were conducted between March 2015 and January 2017. Participants were recruited from 1 hospital in Sweden. A purposeful sampling strategy was used to find family members of persons with symptomatic HF from diverse backgrounds. Data were analyzed using qualitative content analysis. Results: The analysis revealed 4 categories and 9 subcategories. The first category, about how ICT could provide relevant support, included descriptions of how ICT could be used for communication with health care personnel, for information and communication retrieval, plus opportunities to interact with persons in similar life situations and to share support with peers and extended family. The second category, about how ICT could provide access, entailed how ICT could offer solutions not bound by time or place and how it could be both timely and adaptable to different life situations. ICT could also provide an arena for family members to which they might not otherwise have had access. The third category concerned how ICT could be too impersonal and how it could entail limited personal interaction and individualization, which could lead to concerns about usability. It was emphasized that ICT could not replace physical meetings. The fourth category considered how ICT could be out of scope, reflecting the fact that some family members were generally uninterested in ICT and had difficulties envisioning how it could be used for support. It was also discussed as more of a solution for the future. Conclusions: Family members described multiple uses for ICT and agreed that ICT could provide access to relevant sources of information from which family members could potentially exchange support. ICT was also considered to have its limitations and was out of scope for some but with expected use in the future. Even though some family members seemed hesitant about ICT solutions in general, this might not mean they are unreceptive to suggestions about their usage in, for example, health care. Thus, a variety of factors should be considered to facilitate future implementations of ICT tools in clinical practice.

    Place, publisher, year, edition, pages
    JMIR PUBLICATIONS, INC, 2019
    Keywords
    family; caregivers; telemedicine; perception; heart failure; social support; focus groups; qualitative research
    National Category
    Other Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-159249 (URN)10.2196/13521 (DOI)000476841200001 ()31313662 (PubMedID)
    Note

    Funding Agencies|Medical Research Council of Southeast Sweden [FORSS-665001]; Swedish National Science Council (VR) [K2015-99X -22124-04-4]; Swedish National Science Council/Swedish Research Council for Health, Working Life, and Welfare (VR-FORTE) [2014-4100]

    Available from: 2019-08-07 Created: 2019-08-07 Last updated: 2023-11-14
    3. The co-design of an online support programme with and for informal carers of people with heart failure: A methodological paper
    Open this publication in new window or tab >>The co-design of an online support programme with and for informal carers of people with heart failure: A methodological paper
    Show others...
    2023 (English)In: Journal of Clinical Nursing, ISSN 0962-1067, E-ISSN 1365-2702Article in journal (Refereed) Epub ahead of print
    Abstract [en]

    Aim To describe the co-designing process of an online support programme with and for informal carers of people with heart failure.Design A co-design process built on core concepts and ideas embedded in co-design methodology.Data sources Our co-design process included three phases involving 32 informal caregivers and 25 content creators; (1) Identification of topics and content through literature searches, focus group interviews and user group sessions; (2) Development of the online support programme and; (3) Refinement and finalization which included testing a paper prototype followed by testing the online version and testing and approval of the final version of the support programme.Outcomes The co-design process resulted in a support programme consisting of 15 different modules relevant to informal carers, delivered on a National Health Portal.Conclusion Co-design is an explorative process where researchers need to balance a range of potentially conflicting factors and to ensure that the end users are genuinely included in the process.Relevance to clinical practice Emphasizing equal involvement of end users (e.g. carers or patients) in the design and development of healthcare interventions aligns with contemporary ideas of person-centred care and provides a valuable learning opportunity for those involved. Furthermore, a co-designed online support programme has the capacity to be both accessible and meet end users information and support needs, thereby optimizing their self-care abilities. Additionally, an online support programme provides the opportunity to address current challenges regarding scarce resources and the lack of healthcare personnel.Reporting methods Consolidated criteria for reporting qualitative research (COREQ).Patient or public contribution Both informal carers and content creators were involved in developing the support programme.

    Place, publisher, year, edition, pages
    WILEY, 2023
    Keywords
    heart diseases; informal caregiving; information and communication technology; participatory design; web-based support
    National Category
    Other Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-197420 (URN)10.1111/jocn.16856 (DOI)001052348700001 ()37605222 (PubMedID)
    Note

    Funding Agencies|Swedish Research Council for Health, Working Life and Welfare [dnr 2014-4100]; Swedish Research Council; Familjen Kamprads stiftelse [2014-34016-113474-48]; [20210130]

    Available from: 2023-09-05 Created: 2023-09-05 Last updated: 2023-11-14
    Download full text (pdf)
    fulltext
    Download (png)
    presentationsbild
  • Wilson, Johannes
    Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering.
    Formally Verified Remote Attestation Protocols with Strong Authentication2023Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Most commodity processors available today provide hardware-supported security extensions. Remote attestation has been declared an important step towards providing security to users through such solutions, yet remote attestation has seen limited deployment in practice. For existing protocols, analysis of the protocol security is not always publicly available. This thesis utilises formal methods in order to investigate an existing remote attestation protocol in the form of Samsung Knox Enhanced Attestation V3 developed by Samsung for Samsung Knox devices. Requirements are formalised into verifiable security properties. Formal verification reveals a minor weakness when considering strong adversarial models that can control parts of the device through run-time attacks. Such adversarial models are generally stronger than what is typically considered for Knox devices. This thesis also develops general remote attestation protocols which remedy the found weakness with a simple mechanism. Our developed protocols are formally verified, showing that they are suitable for platforms with Trusted Execution Environments even when considering strong adversarial models.

    Download full text (pdf)
    fulltext
  • Knutsson, Alex
    et al.
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Unnebäck, Jakob
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Jönsson, Daniel
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    Eilertsen, Gabriel
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    CDF-Based Importance Sampling and Visualization for Neural Network Training2023In: Eurographics Workshop on Visual Computing for Biology and Medicine / [ed] Thomas Höllt and Daniel Jönsson, 2023Conference paper (Refereed)
    Abstract [en]

    Training a deep neural network is computationally expensive, but achieving the same network performance with less computation is possible if the training data is carefully chosen. However, selecting input samples during training is challenging as their true importance for the optimization is unknown. Furthermore, evaluation of the importance of individual samples must be computationally efficient and unbiased. In this paper, we present a new input data importance sampling strategy for reducing the training time of deep neural networks. We investigate different importance metrics that can be efficiently retrieved as they are available during training, i.e., the training loss and gradient norm. We found that choosing only samples with large loss or gradient norm, which are hard for the network to learn, is not optimal for the network performance. Instead, we introduce an importance sampling strategy that selects samples based on the cumulative distribution function of the loss and gradient norm, thereby making it more likely to choose hard samples while still including easy ones. The behavior of the proposed strategy is first analyzed on a synthetic dataset, and then evaluated in the application of classification of malignant cancer in digital pathology image patches. As pathology images contain many repetitive patterns, there could be significant gains in focusing on features that contribute stronger to the optimization. Finally, we show how the importance sampling process can be used to gain insights about the input data through visualization of samples that are found most or least useful for the training.

    Download full text (pdf)
    fulltext
  • Frick-Lundgren, Martin
    Linköping University, Department of Electrical Engineering, Computer Engineering.
    Evaluation of FPGA-based High Performance Computing Platforms2023Independent thesis Advanced level (degree of Master (Two Years)), 28 HE creditsStudent thesis
    Abstract [en]

    High performance computing is a topic that has risen to the top in the era ofdigitalization, AI and automation. Therefore, the search for more cost and timeeffective ways to implement HPC work is always a subject extensively researched.One part of this is to have hardware that is capable to improve on these criteria. Different hardware usually have different code languages to implement theseworks though, cross-platform solution like Intel’s oneAPI framework is startingto gaining popularity.In this thesis, the capabilities of Intel’s oneAPI framework to implement andexecute HPC benchmarks on different hardware platforms will be discussed. Using the hardware available through Intel’s DevCloud services, Intel’s Xeon Gold6128, Intel’s UHD Graphics P630 and the Arria10 FPGA board were all chosento use for implementation. The benchmarks that were chosen to be used wereGEMM (General Matrix Multiplication) and BUDE (Bristol University DockingEngine). They were implemented using DPC++ (Data Parallel C++), Intel’s ownSYCL-based C++ extension. The benchmarks were also tried to be improved uponwith HPC speed-up methods like loop unrolling and some hardware manipulation.The performance for CPU and GPU were recorded and compared, as the FPGAimplementation could not be preformed because of technical difficulties. Theresults are good comparison to related work, but did not improve much uponthem. This because the hardware used is quite weak compared to industry standard. Though further research on the topic would be interesting, to compare aworking FPGA implementation to the other results and results from other studies. This implementation also probably has the biggest improvement potential,so to see how good one could make it would be interesting. Also, testing someother more complex benchmarks could be interesting.

    Download full text (pdf)
    fulltext
  • Sidiropoulos, Stylianos
    Linköping University, Department of Computer and Information Science.
    Forecasting airline revenue across markets with machine learning2023Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Sales forecasting is an important aspect of business strategy, as it helps companies make informed decisions for their business development. With the rise of machine learning and AI, companies are using statistical and machine learning models to forecast short-term and long-term sales more accurately. In addition, it is important for companies to be able to estimate the impact of advertising on sales for different markets in order to optimize ad campaigns and make informed decisions about their advertising strategies. To address the former problem, ARIMA and LightGBM models with and without feature selection using Lasso regression are used to forecast revenue of an airline across different markets. The performance of the models is measured using Mean Absolute Error (MAE) and Symmetric Mean Absolute Percentage Error (sMAPE) metrics and both of them are compared to a simpler naïve approach called baseline. As for the impact of advertising, CausalImpact package is used to estimate the effect of non-advertising on revenue for each market for a specific period.

    LightGBM models without feature selection performed better in terms of error metrics for the majority of markets with improvements ranging between 41%-77% for sMAPE score and 30%-81% for MAE score when compared with baseline approach. While feature selection aided some markets in achieving lower error scores, it did not consistently improve performance across all markets. As for the effect of non-advertising on revenue, the analysis could not show a negative effect on revenues in all markets. It is difficult to say whether the effect was solely positive or negative for every market, because the results were not statistically significant for most markets, except one.

    Download full text (pdf)
    fulltext
  • Public defence: 2023-12-15 09:15 C3, C-building, LinköpingOrder onlineBuy this publication >>
    Forsling, Robin
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, Faculty of Science & Engineering.
    The Dark Side of Decentralized Target Tracking: Unknown Correlations and Communication Constraints2023Doctoral thesis, monograph (Other academic)
    Abstract [en]

    Using sensors to observe real-world systems is important in many applications. A typical use case is target tracking, where sensor measurements are used to compute estimates of targets. Two of the main purposes of the estimates are to enhance situational awareness and facilitate decision-making. Hence, the estimation quality is crucial. By utilizing multiple sensors, the estimation quality can be further improved. Here, the focus is on target tracking in decentralized sensor networks, where multiple agents estimate a common set of targets. In a decentralized context, measurements undergo local preprocessing at the agent level, resulting in local estimates. These estimates are subsequently shared among the agents for estimate fusion. Sharing information leads to correlations between estimates, which in decentralized sensor networks are often unknown. In addition, there are situations where the communication capacity is constrained, such that the shared information needs to be reduced. This thesis addresses two aspects of decentralized target tracking: (i) fusion of estimates with unknown correlations; and (ii) handling of constrained communication resources. 

    Decentralized sensor networks have unknown correlations because it is typically impossible to keep track of dependencies between estimates. A common approach in this case is to use conservative estimators, which can ensure that the true uncertainty of an estimate is not underestimated. This class of estimators is pursued here. A significant part of the thesis is dedicated to the widely-used conservative method known as covariance intersection (CI), while also describing and deriving alternative methods for CI. One major result related to aspect (i) is the conservative linear unbiased estimator (CLUE), which is proposed as a general framework for optimal conservative estimation. It is shown that several existing methods, including CI, are optimal CLUEs under different conditions. 

    A decentralized sensor network allows for less data to be communicated compared to its centralized counterpart. Yet, there are still situations where the communication load needs to be further reduced. The communication load is mostly driven by the covariance matrices since, in this scope, estimates and covariance matrices are shared. One way to reduce the communication load is to only exchange parts of the covariance matrix. To this end, several methods are proposed that preserve conservativeness. Significant results related to aspect (ii) include several algorithms for transforming exchanged estimates into a lower-dimensional subspace. Each algorithm corresponds to a certain estimation method, and for some of the algorithms, optimality is guaranteed. Moreover, a framework is developed to enable the use of the proposed dimension-reduction techniques when only local information is available at an agent. Finally, an optimization strategy is proposed to compute dimension-reduced estimates while maintaining data association quality. 

    Download full text (pdf)
    fulltext
    Download (png)
    presentationsbild
  • Public defence: 2023-12-08 13:15 BL32 (Nobel), LinköpingOrder onlineBuy this publication >>
    Achieng, Pauline
    Linköping University, Department of Mathematics, Analysis and Mathematics Education. Linköping University, Faculty of Science & Engineering.
    Reconstruction of solutions of Cauchy problems for elliptic equations in bounded and unbounded domains using iterative regularization methods2023Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Cauchy problems for elliptic equations arise in applications in science and engineering. These problems often involve finding important information about an elliptical system from indirect or incomplete measurements. Cauchy problems for elliptic equations are known to be disadvantaged in the sense that a small pertubation in the input can result in a large error in the output. Regularization methods are usually required in order to be able to find stable solutions. In this thesis we study the Cauchy problem for elliptic equations in both bounded and unbounded domains using iterative regularization methods. In Paper I and II, we focus on an iterative regularization technique which involves solving a sequence of mixed boundary value well-posed problems for the same elliptic equation. The original version of the alternating iterative technique is based on iterations alternating between Dirichlet-Neumann and Neumann-Dirichlet boundary value problems. This iterative method is known to possibly work for Helmholtz equation. Instead we study a modified version based on alternating between Dirichlet-Robin and Robin-Dirichlet boundary value problems. First, we study the Cauchy problem for general elliptic equations of second order with variable coefficients in a limited domain. Then we extend to the case of unbounded domains for the Cauchy problem for Helmholtz equation. For the Cauchy problem, in the case of general elliptic equations, we show that the iterative method, based on Dirichlet-Robin, is convergent provided that parameters in the Robin condition are chosen appropriately. In the case of an unbounded domain, we derive necessary, and sufficient, conditions for convergence of the Robin-Dirichlet iterations based on an analysis of the spectrum of the Laplacian operator, with boundary conditions of Dirichlet and Robin types.

    In the numerical tests, we investigate the precise behaviour of the Dirichlet-Robin iterations, for different values of the wave number in the Helmholtz equation, and the results show that the convergence rate depends on the choice of the Robin parameter in the Robin condition. In the case of unbounded domain, the numerical experiments show that an appropriate truncation of the domain and an appropriate choice of Robin parameter in the Robin condition lead to convergence of the Robin-Dirichlet iterations.

    In the presence of noise, additional regularization techniques have to implemented for the alternating iterative procedure to converge. Therefore, in Paper III and IV we focus on iterative regularization methods for solving the Cauchy problem for the Helmholtz equation in a semi-infinite strip, assuming that the data contains measurement noise. In addition, we also reconstruct a radiation condition at infinity from the given Cauchy data. For the reconstruction of the radiation condition, we solve a well-posed problem for the Helmholtz equation in a semi-infinite strip. The remaining solution is obtained by solving an ill-posed problem. In Paper III, we consider the ordinary Helmholtz equation and use seperation of variables to analyze the problem. We show that the radiation condition is described by a non-linear well-posed problem that provides a stable oscillatory solution to the Cauchy problem. Furthermore, we show that the ill–posed problem can be regularized using the Landweber’s iterative method and the discrepancy principle. Numerical tests shows that the approach works well.

    Paper IV is an extension of the theory from Paper III to the case of variable coefficients. Theoretical analysis of this Cauchy problem shows that, with suitable bounds on the coefficients, can iterative regularization methods be used to stabilize the ill-posed Cauchy problem.

    List of papers
    1. Analysis of Dirichlet–Robin Iterations for Solving the Cauchy Problem for Elliptic Equations
    Open this publication in new window or tab >>Analysis of Dirichlet–Robin Iterations for Solving the Cauchy Problem for Elliptic Equations
    2021 (English)In: Bulletin of the Iranian Mathematical Society, ISSN 1735-8515, Vol. 47, p. 1681-1699Article in journal (Refereed) Published
    Abstract [en]

    The Cauchy problem for general elliptic equations of second order is considered. In a previous paper (Berntsson et al. in Inverse Probl Sci Eng 26(7):1062–1078, 2018), it was suggested that the alternating iterative algorithm suggested by Kozlov and Maz’ya can be convergent, even for large wavenumbers k2, in the Helmholtz equation, if the Neumann boundary conditions are replaced by Robin conditions. In this paper, we provide a proof that shows that the Dirichlet–Robin alternating algorithm is indeed convergent for general elliptic operators provided that the parameters in the Robin conditions are chosen appropriately. We also give numerical experiments intended to investigate the precise behaviour of the algorithm for different values of k2 in the Helmholtz equation. In particular, we show how the speed of the convergence depends on the choice of Robin parameters.

    Place, publisher, year, edition, pages
    Springer, 2021
    Keywords
    Helmholtz equation, Cauchy problem, Inverse problem, Ill-posed problem
    National Category
    Mathematical Analysis
    Identifiers
    urn:nbn:se:liu:diva-170834 (URN)10.1007/s41980-020-00466-7 (DOI)000575739300001 ()2-s2.0-85092146699 (Scopus ID)
    Available from: 2020-10-26 Created: 2020-10-26 Last updated: 2023-11-13Bibliographically approved
    2. Robin-Dirichlet alternating iterative procedure for solving the Cauchy problem for Helmholtz equation in an unbounded domain
    Open this publication in new window or tab >>Robin-Dirichlet alternating iterative procedure for solving the Cauchy problem for Helmholtz equation in an unbounded domain
    2023 (English)In: Journal of Inverse and Ill-Posed Problems, ISSN 0928-0219, E-ISSN 1569-3945Article in journal (Refereed) Epub ahead of print
    Abstract [en]

    We consider the Cauchy problem for the Helmholtz equation with a domain in with N cylindrical outlets to infinity with bounded inclusions in . Cauchy data are prescribed on the boundary of the bounded domains and the aim is to find solution on the unbounded part of the boundary. In 1989, Kozlov and Mazya proposed an alternating iterative method for solving Cauchy problems associated with elliptic, selfadjoint and positive-definite operators in bounded domains. Different variants of this method for solving Cauchy problems associated with Helmholtz-type operators exists. We consider the variant proposed by Berntsson, Kozlov, Mpinganzima and Turesson (2018) for bounded domains and derive the necessary conditions for the convergence of the procedure in unbounded domains. For the numerical implementation, a finite difference method is used to solve the problem in a simple rectangular domain in R-2 that represent a truncated infinite strip. The numerical results shows that by appropriate truncation of the domain and with appropriate choice of the Robin parameters mu(0) and mu(1), the Robin-Dirichlet alternating iterative procedure is convergent.

    Place, publisher, year, edition, pages
    WALTER DE GRUYTER GMBH, 2023
    Keywords
    Helmholtz equation; Cauchy problem; inverse problem ill-posed problem
    National Category
    Computational Mathematics
    Identifiers
    urn:nbn:se:liu:diva-192481 (URN)10.1515/jiip-2020-0133 (DOI)000940871600001 ()
    Available from: 2023-03-21 Created: 2023-03-21 Last updated: 2023-11-13
    3. Reconstruction of the Radiation Condition and Solution for the Helmholtz Equation in a Semi-infinite Strip from Cauchy Data on an Interior Segment
    Open this publication in new window or tab >>Reconstruction of the Radiation Condition and Solution for the Helmholtz Equation in a Semi-infinite Strip from Cauchy Data on an Interior Segment
    2023 (English)In: Computational Methods in Applied Mathematics, ISSN 1609-4840, E-ISSN 1609-9389Article in journal (Refereed) Epub ahead of print
    Abstract [en]

    We consider an inverse problem for the Helmholtz equation of reconstructing a solution from measurements taken on a segment inside a semi-infinite strip. Homogeneous Neumann conditions are prescribed on both side boundaries of the strip and an unknown Dirichlet condition on the remaining part of the boundary. Additional complexity is that the radiation condition at infinity is unknown. Our aim is to find the unknown function in the Dirichlet boundary condition and the radiation condition. Such problems appear in acoustics to determine acoustical sources and surface vibrations from acoustic field measurements. The problem is split into two sub-problems, a well-posed and an ill-posed problem. We analyse the theoretical properties of both problems; in particular, we show that the radiation condition is described by a stable non-linear problem. The second problem is ill-posed, and we use the Landweber iteration method together with the discrepancy principle to regularize it. Numerical tests show that the approach works well.

    Place, publisher, year, edition, pages
    WALTER DE GRUYTER GMBH, 2023
    Keywords
    Helmholtz Equation; Inverse Problem; Cauchy Problem; Ill-Posed Problem; Well-Posed Problem; Landweber Method
    National Category
    Fluid Mechanics and Acoustics
    Identifiers
    urn:nbn:se:liu:diva-196637 (URN)10.1515/cmam-2022-0244 (DOI)001035412500001 ()
    Available from: 2023-08-17 Created: 2023-08-17 Last updated: 2023-11-13
    Download full text (pdf)
    fulltext
    Download (png)
    presentationsbild
  • Zackrisson, Anton
    Linköping University, Department of Management and Engineering.
    When is Electric Freight Cost Competitive?: Computational modeling and simulation of total cost of ownership for electric truck fleets2023Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Battery electric trucks (BETs) offer environmental benefits in terms of reduced carbon emissions and enhanced energy efficiency but have been challenged with economic viability compared to conventional internal combustion engine trucks (ICETs) caused by substantial acquisition costs, limited charging infrastructure, and concerns regarding range and payload capacity. 

    Previous studies focus on TCO at the vehicle or policy level but overlook the system and firm-level impacts. Operational aspects like vehicle utilization, battery utilization, charging planning, and route optimization are often ignored, potentially underestimating electric freight cost-competitiveness.The research gap does not address the practical needs of fleet operators, especially in scenarios where charging infrastructure is lacking. There is therefore a need to consider the complex system level interactions, market dynamics, technology developments, and operational processes involved in freight shipping.

    By applying a decision-making under deep uncertainty (DMDU) framework, this study enables informed decisions in unpredictable scenarios, bridging the gap between strategic choices like battery capacity and operational optimization like route planning. This study identifies the most significant factors that affect the TCO of BET fleets and cost-competitiveness relative to ICET fleets, taking into account market-operational interfaces between unpredictable market dynamics and operational processes such as stochastic demand and feature selection from a strategic and operational perspective. 40 tonne truck-trailers for freight distribution networks with distances up to 250 km are considered in the study. 

    A TCO model of BET and ICET fleets was developed taking into account vehicle route optimization, vehicle selection, and vehicle utilization which was then programmatically iterated by sampling and simulating optimized vehicle routes for a total of 220 224 iterations. The parameter space was screened and reduced with Feature Scoring using Extra Trees approximation of 1st order Sobol Indices. The reduced parameter space was then sampled using Sobol sampling to conduct a Sobol Global Variance decomposition Analysis of TCO, TCO delta, and service level in order to identify the most significant factors affecting BET fleet TCO and cost-competitiveness.To identify cost-competitive scenarios, the Patient Rule Induction Method (PRIM) was used to identify parameter sub spaces to determine scenarios where BET fleets have a lower TCO than ICET fleets. Further visual analysis was done using linear and polynomial regression and kernel density estimation.

    The analysis shows that both TCO and cost-competitiveness of BETs are primarily affected by shipment demand, distance between distribution center and delivery sites, and battery size, and that a trade-off is made between cost-competitiveness and service level. The results show that cost-competitiveness of electric freight scales with demand, with larger fleets being better able to optimize routing and shipment allocation; balancing the shipment demand to minimize charging times that otherwise would make the fleet less competitive than their fossil-fuel counterparts. This, paired together with higher degrees of vehicle utilization and appropriate battery sizing, allow for electric freight to be cost-competitive even for long-haul distances up to 250 km. 

    Furthermore, optimization of the Electric Vehicle Routing Problem (E-VRP) with shifts and time windows is shown to have a highly significant effect when minimizing TCO on a fleet level, with the vast majority of optimal ICET routes not being optimal for BETs.The benefits of E-VRP optimization scales with demand and fleet size, indicating that large-scale electrification is required to make BETs cost-competitive.Electrification of road freight is therefore highly contingent on effective route planning and charging scheduling with E-VRP optimization in order to be cost-competitive, which has not been considered in previous literature. Thus previous literature have therefore likely underestimated the cost-competitiveness of electric freight, particularly at medium-long haul distances. 

    Download full text (pdf)
    computational_modeling_and_simulation_of_BET_TCO
  • Public defence: 2023-12-14 09:15 ACAS, A-building, LinköpingOrder onlineBuy this publication >>
    Fältström, Emma
    Linköping University, Department of Management and Engineering, Environmental Technology and Management. Linköping University, Faculty of Science & Engineering.
    Mitigating Microplastics Pollution in Urban Water Systems: Flow, actors, and control measures2023Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Water pollution has long been considered a challenge in urban areas. Urban wastewater and stormwater act as transport pathways for pollutants from urban areas to receiving waters. Microplastics are a pollution problem of growing concern. As part of the zero-pollution action plan for 2050, the European Commission has set the target to reduce emissions of microplastics to the environment by 30% from 2016 to 2030. The majority of the microplastics originate from sources on land, and urban areas are viewed as particular hotspots. More knowledge is needed on the sources and pathways of microplastics within the urban area, such as to and from urban water systems. To be able to reduce microplastics pollution, there is also a need to understand where control measures can be introduced and make an impact in terms of reduced loads to the environment. For control measures to be implemented, there is also a need to understand the incentives and challenges that the actors, who have a responsibility related to the flows, encounter when working with pollution control.   

    The aim of this thesis was to contribute to enhanced understanding of flows of microplastics in urban water systems and how the flows can be controlled, in order to facilitate mitigation actions for these flows. This aim was addressed by identifying and quantifying sources with emissions to urban wastewater and stormwater and pathways from the urban water system, with inspiration from the method substance flow analysis. The estimated sources were also compared to measurements in raw wastewater and stormwater from four different catchments to identify matches and differences. Further, control measures were introduced to the quantified sources and pathways. Municipal officials, who can implement the control measures, were also interviewed about their incentives and challenges when controlling microplastics and other pollutants in the urban water system.   

    The emissions of microplastics to stormwater were estimated to be much higher than those to wastewater. Tyre wear particles and cigarette butts were estimated to be the largest sources. While stormwater measurements confirmed tyre wear particles, cigarette butts, and paint particles, which was another large source according to the source estimates, could not be confirmed. Instead, the samples contained other types of microplastics. These mismatches indicate that large flows of microplastics may come from sources that have yet to be identified and quantified. The largest source to wastewater was estimated to be synthetic fibres (mainly polyester) released during laundry washing. Polyester also had the largest share in the wastewater measurements. Untreated stormwater was the largest pathway to receiving waters, followed by treated stormwater. Treated wastewater and overflows had comparatively small emissions. The measures introduced to wastewater had the potential to reduce the load of microplastics in the wastewater by half. However, as wastewater treatment retain most of the microplastics, and because the largest emissions came from stormwater, this reduction made a small difference in terms of total loads to receiving waters. Reduced urban traffic, changed driving behaviour, and more stormwater treatment, were also required to reduce emissions of microplastics from the urban water system to receiving waters by 30% in accordance with the EU target.   

    Three types of incentives for pollution control among the municipal officials were identified. One incentive was that pollution control positively affected other aspects that were seen as important, such as that it had economic benefits or increased water- and sludge quality. Another incentive was a perceived responsibility for water quality, for the environment, or to be role models. A third incentive was a “pressure” to act from the local environmental control authorities or through local politics. The challenges for pollution control were primarily related to insufficient resources in terms of time, finances, and knowledge. Changing, limited, or lack of legislation was also identified as a challenge. Other identified challenges, such as unclear responsibilities and unclear expectations of the work, can be alleviated with a strategy or plan, but a plan did not ease all challenges. Support, in terms of financial means and guidance, is also needed so that actions set out in the plans can be implemented.  

    So far, the control measures for microplastics related to urban water systems have primarily been preventive and focused on restricting use of microplastics in certain applications. There are no restrictions on emissions yet. If such restrictions come, where they are placed will impact the type of measures that will be introduced. This, in turn, will have consequences at the system level: for example, if it will lead to emissions in another part of the system, and which actors will be responsible for managing the pollution. 

    List of papers
    1. Towards control strategies for microplastics in urban water
    Open this publication in new window or tab >>Towards control strategies for microplastics in urban water
    2020 (English)In: Environmental Science and Pollution Research, ISSN 0944-1344, E-ISSN 1614-7499, Vol. 27, no 32, p. 40421-40433Article in journal (Refereed) Published
    Abstract [en]

    Microplastics (plastic particles &lt; 5 mm) is a pollution of growing concern. Microplastic pollution is a complex issue that requires systematic attempts to provide an overview and avoid management solutions that have marginal effects or only move the pollution problem. Substance flow analysis (SFA) has been proposed as a useful tool to receive such an overview and has been put forward as valuable for substance management. However, as the research on microplastics has only emerged recently, detailed and reliable SFAs are difficult to perform. In this study, we use three SFA studies for three pollutants (cadmium, copper and pharmaceuticals) to compare flows and strategies to control the flows. This in order to seek guidance for microplastic management and evaluate potential strategies for controlling microplastics. The analysis shows that there has been rigorous control on different levels to abate pollution from cadmium, copper and pharmaceuticals, but where in the system the major control measures have been carried out differ. For microplastics, there are many potential solutions, both in terms of preventive actions and treatment depending on the type of source. When forming management plans for microplastics, the responsibility for each measure and the impact on the whole urban system should be taken into consideration as well as which receiving compartments are particularly valuable and should be avoided.

    Place, publisher, year, edition, pages
    SPRINGER HEIDELBERG, 2020
    Keywords
    Control strategies; Pollution management; Stormwater; Substance flow analysis; SFA; Wastewater; Urban water
    National Category
    Environmental Sciences
    Identifiers
    urn:nbn:se:liu:diva-168530 (URN)10.1007/s11356-020-10064-z (DOI)000548518400018 ()32666462 (PubMedID)
    Note

    Funding Agencies|Linkoping University

    Available from: 2020-08-28 Created: 2020-08-28 Last updated: 2023-11-10
    2. Microplastic Types in the Wastewater System: A Comparison of Material Flow-Based Source Estimates and the Measurement-Based Load to a Wastewater Treatment Plant
    Open this publication in new window or tab >>Microplastic Types in the Wastewater System: A Comparison of Material Flow-Based Source Estimates and the Measurement-Based Load to a Wastewater Treatment Plant
    2021 (English)In: Sustainability, E-ISSN 2071-1050, Vol. 13, no 10, article id 5404Article in journal (Refereed) Published
    Abstract [en]

    Microplastics are omnipresent in the environment, and wastewater treatment plants (WWTPs) have been highlighted as a transport pathway. The aim of this study is to contribute to increased understanding of microplastic sources in wastewater and test the possibilities of source tracking. Previous research has focused either on estimating microplastic contribution from various sources or on quantifying occurrence based on measurements. In this paper, these two approaches are compared. Microplastic types detected in the influent to a WWTP in Sweden are compared with estimations of sources in the WWTP catchment area. The total load from the identified sources was estimated to 1.9-14 tonnes/year, and the measurement-based load was 4.2 tonnes/year. In general, there was a good agreement between the two approaches; microplastic types with large shares at the inlet also had large contributions in the source estimates. An exception was cellulose acetate, which was not found at the inlet despite a large theoretical contribution. Many uncertainties remain, which lead to large intervals for the source estimates. The comparison can give an indication into which part of the intervals is most likely. Investigating more WWTPs with different characteristics and including particle morphology will further increase the understanding of sources that contribute to the presence of microplastics in wastewater.

    Place, publisher, year, edition, pages
    MDPI, 2021
    Keywords
    FTIR; polymer; substance flow analysis; source tracking; stormwater
    National Category
    Environmental Sciences
    Identifiers
    urn:nbn:se:liu:diva-177867 (URN)10.3390/su13105404 (DOI)000662503900001 ()
    Note

    Funding Agencies|Swedish Water and Wastewater Association [16-111]

    Available from: 2021-07-06 Created: 2021-07-06 Last updated: 2023-11-10
    3. Upstream pollution control by water utilities in Sweden: incentives and challenges
    Open this publication in new window or tab >>Upstream pollution control by water utilities in Sweden: incentives and challenges
    2021 (English)In: Water Policy, ISSN 1366-7017, E-ISSN 1996-9759, Vol. 23, no 6, p. 1400-1414Article in journal (Refereed) Published
    Abstract [en]

    Wastewater treatment plants (WWTPs) are not designed to handle many harmful substances that are present in the wastewater. The substances can also be transferred to the sewage sludge, which can make it unsuitable as a fertiliser. To alleviate these problems, Sweden has a practice called upstream work (uppstromsarbete) that aims to prevent harmful substances from entering the wastewater via efforts to control the pollution closer to the source. Upstream work has produced positive results in terms of reduced pollution in water and sludge and is seen as an important practice by both practicians and policymakers. In this paper, we investigate the incentives and challenges for upstream work as experienced by practitioners at municipal water utilities. The results show that there are two types of incentives: one related to practical problems and the other related to a perceived responsibility for the wastewater system and for the environment. The challenges were primarily related to an insufficient organisational structure for upstream work, manifested in unclear responsibilities, lack of prioritisation, and insufficient resources. The findings can be used to expand and initiate pollution control upstream of the WWTP as part of the urban water management, as well as decision support for policymakers.

    Place, publisher, year, edition, pages
    IWA Publishing, 2021
    Keywords
    Barriers; Drivers; Pollution control; Pollution prevention; Sewage sludge; Source control; Upstream work; Urban waters; Wastewater
    National Category
    Water Engineering
    Identifiers
    urn:nbn:se:liu:diva-180369 (URN)10.2166/wp.2021.047 (DOI)000703211400001 ()
    Note

    Funding Agencies|Swedish Water and Wastewater Association [16-123]

    Available from: 2021-10-18 Created: 2021-10-18 Last updated: 2023-11-10
    Download full text (pdf)
    fulltext
    Download (png)
    presentationsbild
  • Norberg, Josefin
    Linköping University, Department of Behavioural Sciences and Learning.
    Jag hör och jag glömmer, jag gör och jag förstår: - En litteraturstudie om upplevelsebaserat lärande inom samhällsorienterande ämnena2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Download full text (pdf)
    fulltext
  • Sallstedt, Celine
    et al.
    Linköping University, Department of Behavioural Sciences and Learning.
    Gadmar, Emelie
    Linköping University, Department of Behavioural Sciences and Learning.
    "På något sätt när vi kommer ut så försvinner det": Bildstöd i förskolans inne- och utemiljöer2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Syftet med den här studien är att bidra med kunskap om hur bildstöd används både i förskolan inne- och utemiljö. Utifrån två frågeställningar vill vi ta reda på hur bildstöd används i de olika miljöerna, samt hur det skiljer sig åt. Vi har genomfört en studie med både kvantitativ- och kvalitativ metod, genom observationer och intervjuer, för att kunna ge ett bredare perspektiv på vår studie. Genom observationerna fick vi ett sammanställt resultat med antal för bildstödets användande, medan intervjuerna gav oss en mer djupgående bild för hur verksamheterna arbetar med bildstöd. Utifrån våra frågeställningar samt vårt insamlade material skapade vi sex stycken teman för att kunna genomföra en grundlig analys. Resultatet genom observationerna visar att det finns tydliga skillnader mellan inne- och utemiljöer, vilket också intervjuerna bekräftade. Genom citat från intervjuerna har analys och tolkning gjorts för att kunna få ökad förståelse för varför bildstöd inte finns i lika stor mängd utomhus. Slutligen diskuterar vi resultatet för att sammanställa studiens slutsatser och genom dessa besvara frågeställningarna.

    Download full text (pdf)
    fulltext
  • Public defence: 2024-01-12 13:00 Berzeliussalen, LinköpingOrder onlineBuy this publication >>
    Södermark, Martin
    Linköping University, Department of Health, Medicine and Caring Sciences, Division of Prevention, Rehabilitation and Community Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Pain and Rehabilitation Center.
    Emotion Regulation in Pain: Developing Effective Interventions for Patients with Pain and Emotional Distress2023Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Chronic pain and emotional problems are common, often co-occur, and result in substantial suffering and social costs. Cognitive Behavioral Therapy (CBT) is a family of treatments that have been extensively studied and has empirical support for its effectiveness in treating both conditions. However, CBT show small benefits for patients with comorbid pain and emotional disorders, and treatments are mostly adapted for one condition or the other. Hence, there is a need for transdiagnostic interventions, targeting both problematic pain behaviors and emotional components. In this thesis, I present results from three experimental studies investigating possibilities to refine and enhance CBT for chronic pain patients with emotional distress by using emotion regulation strategies and skills training from mindfulness-based interventions.

    In Study I the aim was to evaluate the efficacy of a tailored transdiagnostic hybrid treatment, integrating basic CBT principles with strategies from Dialectical Behavior Therapy (DBT), an acceptance and mindfulnessbased approach developed for individuals with difficulties regulating emotional responses. The hybrid treatment was compared in a randomised controlled trial to an internet-delivered active control condition (iCBT). Intent-to-treat analyses showed that the hybrid treatment had positive long-term effects 9 months after treatment on outcomes such as pain interference and symptoms of depression compared to the control condition. We concluded that the hybrid treatment may be considered an acceptable, credible, and efficacious treatment approach.

    In Study II the aim was to investigate the importance of hypothesized treatment processes of the hybrid treatment, specifically pain-related dysregulation (catastrophizing, fear-avoidance, and non-acceptance of pain), and general emotion dysregulation (difficulties to regulate a wider range of emotional responses). Mediation analysis within the framework of structural equation modelling (SEM), using the full intention-to-treat sample, showed that decreased pain-related dysregulation mediated the effects of the hybrid treatment on both pain interference and symptoms of depression. Furthermore, indirect effects through pain-related dysregulation were more evident for participants scoring higher on this variable at baseline. In addition, decreased general emotion dysregulation mediated effects on symptoms of depression. We concluded that these findings provided further support for the conceptual principles of the hybrid treatment.

    The aim of Study III was to investigate the effects of components of mindfulness-based interventions, specifically looking at the importance of attentional focus during mindfulness exercises on experiences of experimentally induced pain using the Cold Pressor Test (CPT). In a mixed experimental design, healthy participants were randomly assigned to brief mindfulness exercises with internal focus (body scan), external focus (mindful listening), or a control group using spontaneous coping. Compared to spontaneous coping the mindfulness exercises had positive effects on pain tolerance, pain threshold, pain unpleasantness, frequency of negative thoughts, and belief in thought content during the CPT. While our results showed that changes in attentional focus were consistent with the experimental manipulation, no significant differences were found between internal and external focus on any outcome measure. We concluded that the results did not support the notion that attentional focus would be essential for benefits of mindfulness, and that exercises with both external and internal focus could be beneficial when coping with pain.

    In conclusion, the results from these studies support integrating basic CBT principles with emotion regulation strategies and skills training from mindfulness-based approaches to enhance treatments for patients with chronic pain and emotional distress. In addition, our findings provide some insights for future research regarding the importance of targeting pain-related dysregulation, and the possibilities of using mindfulness exercises with different attentional focus.

    List of papers
    1. Efficacy of a transdiagnostic emotion-focused exposure treatment for chronic pain patients with comorbid anxiety and depression: a randomized controlled trial
    Open this publication in new window or tab >>Efficacy of a transdiagnostic emotion-focused exposure treatment for chronic pain patients with comorbid anxiety and depression: a randomized controlled trial
    Show others...
    2019 (English)In: Pain, ISSN 0304-3959, E-ISSN 1872-6623, Vol. 160, no 8, p. 1708-1718Article in journal (Refereed) Published
    Abstract [en]

    The comorbidity between chronic pain and emotional problems has proven difficult to address with current treatment options. This study addresses the efficacy of a transdiagnostic emotion-focused exposure treatment ("hybrid") for chronic pain patients with comorbid emotional problems. Adults (n = 115) with chronic musculoskeletal pain and functional and emotional problems were included in a 2-centre, parallel randomized controlled, open-label trial comparing this treatment to an active control condition receiving a guided Internet-delivered pain management treatment based on CBT principles (iCBT). The hybrid treatment (n = 58, 10-16 sessions) integrates exposure in vivo for chronic pain based on the fear-avoidance model with an emotion-regulation approach informed by procedures in Dialectical Behavior Therapy. The iCBT (n = 57; 8 treatment modules) addresses topics such as pain education, coping strategies, relaxation, problem solving, stress, and sleep management using standard CBT techniques. Patient-reported outcomes were assessed before and after treatment as well as at a 9-month primary end point. Across conditions, 78% participants completed post-treatment and 81% follow-up assessment. Intent-to-treat analyses showed that the hybrid had a significantly better post-treatment outcome on pain catastrophizing (d = 0.39) and pain interference (d = 0.63) and significantly better follow-up outcomes on depression (d = 0.43) and pain interference (d = 0.51). There were no differences on anxiety and pain intensity. Observed proportions of clinically significant improvement favoured the hybrid on all but one comparison, but no statistically significant differences were observed. We conclude that the hybrid emotion-focused treatment may be considered an acceptable, credible, and efficacious treatment option for chronic pain patients with comorbid emotional problems.

    Place, publisher, year, edition, pages
    Lippincott Williams & Wilkins, 2019
    Keywords
    Chronic pain; Emotional problems; Transdiagnostic; Cognitive-behavioral therapy; Internet; Randomized clinical trial; Exposure
    National Category
    General Practice
    Identifiers
    urn:nbn:se:liu:diva-160052 (URN)10.1097/j.pain.0000000000001575 (DOI)000480764500006 ()31335641 (PubMedID)2-s2.0-85066118471 (Scopus ID)
    Note

    Funding Agencies|AFA insurance [140356]; Region Ostergotland [LIO-724821]; Swedish Foundation for Humanities and Social Sciences [P14-0799: 1]

    Available from: 2019-09-06 Created: 2019-09-06 Last updated: 2023-11-10Bibliographically approved
    2. What Works? Processes of Change in a Transdiagnostic Exposure Treatment for Patients With Chronic Pain and Emotional Problems
    Open this publication in new window or tab >>What Works? Processes of Change in a Transdiagnostic Exposure Treatment for Patients With Chronic Pain and Emotional Problems
    Show others...
    2020 (English)In: The Clinical Journal of Pain, ISSN 0749-8047, E-ISSN 1536-5409, Vol. 36, no 9, p. 648-657Article in journal (Refereed) Published
    Abstract [en]

    Objectives: We recently developed a transdiagnostic exposure treatment (the hybrid treatment) for chronic pain patients with concurrent emotional difficulties. This paper investigates the hypothesized treatment processes, specifically: (1) if changes on pain-related dysregulation (catastrophizing, fear-avoidance, and nonacceptance of pain) and general emotion dysregulation (difficulties to regulate a broad spectrum of emotional responses) mediate effects on outcomes; and (2) if mediation is more pronounced for patients who score higher on these processes pretreatment. Materials and Methods: Structural equation modeling for longitudinal data using the full intention-to-treat sample was used to test whether proposed variables mediated the effect of the hybrid treatment (n=58) compared with a guided internet-delivered pain management treatment based on cognitive-behavioral principles (n=57) on pain interference and depressive symptoms at the 9-month follow-up. To make full use of the multiple process measures collected in the trial, we modeled mediators as 2 continuous latent variables: pain-related dysregulation and general emotion dysregulation. Results: Reduced pain-related dysregulation mediated the effects of treatment on both outcomes, whereas reduced general emotion dysregulation mediated the effects on depressive symptoms only. In the hybrid treatment, the mediated effect was more pronounced for participants who scored higher on pain-related dysregulation pretreatment relative to those who scored lower. Discussion: Our findings provide initial support for the transdiagnostic theoretical underpinnings of the hybrid treatment model. Using a hybrid treatment approach that centers on teaching patients emotion-regulation skills before commencing broad exposure successfully influenced both pain-related dysregulation and general emotion dysregulation, which in turn was associated with better treatment outcomes. It appears central to address these processes in pain patients with comorbid emotional problems, especially among patients scoring high on measures of catastrophizing, fear-avoidance, and nonacceptance of pain.

    Place, publisher, year, edition, pages
    LIPPINCOTT WILLIAMS & WILKINS, 2020
    Keywords
    chronic pain; depression; cognitive-behavioral therapy; emotion regulation
    National Category
    Applied Psychology
    Identifiers
    urn:nbn:se:liu:diva-170672 (URN)10.1097/AJP.0000000000000851 (DOI)000570150800002 ()32520820 (PubMedID)
    Note

    Funding Agencies|AFA insurance, Stockholm, Sweden [140356]; Region Ostergotland, Linkoping, Sweden [LIO-724821]; Swedish Foundation for Humanities and Social Sciences, Stockholm, Sweden [P14-0799:1]

    Available from: 2020-10-19 Created: 2020-10-19 Last updated: 2023-11-10
    Download full text (pdf)
    fulltext
    Download (png)
    presentationsbild
  • Order onlineBuy this publication >>
    Choolakkal, Arun Haridas
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Conformal chemical vapor deposition of boron carbide thin films2023Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    The sustainability goals of the modern world and the fascinating properties of sub-micron scale materials promote development of materials in thin film form. Thin films are materials that have thicknesses ranging from sub-nanometer to several micrometers, synthesized by various deposition techniques. They are used for diverse applications, such as light emitting diodes, solar cells, semiconductor chips, etc. The primary objective of this research project is to develop a chemical vapor deposition (CVD) process for conformal boron carbide thin films. Since boron carbide is a promising neutron converter material for solid-state neutron detectors, the process was validated by depositing on prototype detector chips.  

    In this study, triethylboron (TEB) was used as single source CVD precursor to deposit boron carbide thin films. The initial experiments focused on low reaction rate deposition by depositing in a kinetically limited regime. The films deposited at ≤450 °C in 8:1 aspect ratio micro-trench structures were highly conformal and show a stoichiometry of about B5.2C. We attribute this observed conformality to the slow reaction kinetics of the TEB at the low deposition temperature enabling the diffusive transport of the precursor molecule down the trench. The depositions carried out on the prototype detector-chips show promising results.  

    We expand our studies to investigate a new strategy with the prospect of improving the step coverage at higher temperatures for better film properties. We hypothesize that adding a suitable heavier molecule, diffusion additive, with an appropriate partial pressure can enhance the step coverage by pushing the lighter precursor molecule via competitive co-diffusion. It was tested by adding Xe gas to the boron carbide CVD from TEB. The result shows that with this diffusion additive the step coverage was improved from 0.71 to 0.97. From our experimental results, we suggest a competitive diffusion model that can be adapted to other CVD processes to enhance the film step coverage.  

    The CVD process is further validated by depositing onto carbon nanotube membranes. The initial results show that the process was able to afford evenly deposition around the individual nanotubes in the carbon nanotube membrane. Raman spectroscopy measurements show a similar D-band to G-band intensity ratio before and after the deposition indicating that no defects were induced in the nanotubes.      

    List of papers
    1. Conformal chemical vapor deposition of boron-rich boron carbide thin films from triethylboron
    Open this publication in new window or tab >>Conformal chemical vapor deposition of boron-rich boron carbide thin films from triethylboron
    2023 (English)In: Journal of Vacuum Science & Technology. A. Vacuum, Surfaces, and Films, ISSN 0734-2101, E-ISSN 1520-8559, Vol. 41, no 1, article id 013401Article in journal (Refereed) Published
    Abstract [en]

    We report conformal chemical vapor deposition (CVD) of boron carbide (BxC) thin films on silicon substrates with 8:1 aspect-ratio morphologies, using triethylboron [B(C2H5)(3)] as a single source CVD precursor. Step coverage (SC) calculated from the cross-sectional scanning electron microscopy measurements shows that films deposited at & LE;450 & DEG;C were highly conformal (SC = 1). We attribute this to the low reaction probability at low substrate temperatures enabling more gas phase diffusion into the features. The chemical state of the material, determined by x-ray photoelectron spectroscopy, shows as a carbide with B-B, B-C, C-B, and C-C chemical bonds. Quantitative analysis by time-of-flight elastic recoil detection analysis reveals that films deposited at 450 & DEG;C are boron-rich with around 82.5 at. % B, 15.6 at. % C, 1.3 at. % O, and 0.6 at. % H, i.e., about B5C. The film density as measured by x-ray reflectometry varies from 1.9 to 2.28 g/cm(3) depending on deposition temperature. (C) 2022 Author(s).All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY)license (http://creativecommons.org/licenses/by/4.0/).

    Place, publisher, year, edition, pages
    A V S AMER INST PHYSICS, 2023
    National Category
    Materials Chemistry
    Identifiers
    urn:nbn:se:liu:diva-190923 (URN)10.1116/6.0002203 (DOI)000894732600002 ()
    Note

    Funding Agencies|Swedish Research Council (VR) [2018-05499]; Swedish Government Strategic Research Area in Materials Science on Advanced Functional Materials at Linkoping University [2009-00971]; Swedish research council VR-RFI [2019-00191]

    Available from: 2023-01-09 Created: 2023-01-09 Last updated: 2023-11-09
    2. 3D silicon detectors for neutron imaging applications
    Open this publication in new window or tab >>3D silicon detectors for neutron imaging applications
    Show others...
    2023 (English)In: Journal of Instrumentation, ISSN 1748-0221, E-ISSN 1748-0221, Vol. 18, no 1, article id C01056Article in journal (Refereed) Published
    Abstract [en]

    Neutron detection is of great importance in many fields spanning from scientific research, to nuclear science, and to medical application. The development of silicon-based neutron detectors with enhanced neutron detection efficiency can offer several advantages such as spatial resolution, enhanced dynamic range and background discrimination. In this work, increased detection efficiency is pursued by fabricating high aspect ratio 3D micro-structures filled with neutron converting materials (B4C) on planar silicon detectors. An in-depth feasibility study was carried out in all aspects of the sensor fabrication technology. Passivation of the etched structures was studied in detail, to ensure good electrical performance. The conformal deposition of B4C with a newly developed process showed excellent results. Preliminary electrical characterisation of the completed devices is promising, and detectors have been mounted on dedicated boards in view of the upcoming tests with neutrons.

    Place, publisher, year, edition, pages
    IOP Publishing Ltd, 2023
    Keywords
    Neutron detectors (cold; thermal; fast neutrons); Solid state detectors; Detector mod-elling and simulations I (interaction of radiation with matter; interaction of photons with matter; interaction of hadrons with matter; etc; ); Detector modelling and simulations II (electric fields; charge transport; multiplication and induction; pulse formation; electron emission
    National Category
    Accelerator Physics and Instrumentation
    Identifiers
    urn:nbn:se:liu:diva-192958 (URN)10.1088/1748-0221/18/01/C01056 (DOI)000948372200014 ()
    Conference
    23rd International Workshop on Radiation Imaging Detectors, Riva del Garda, ITALY, jun 26-30, 2022
    Note

    Funding Agencies|Research Council of Norway [289437]; Swedish Research Council [2018-05499]; Swedish Government Strategic Research Area in Materials Science on Advanced Functional Materials (AFM) at Linkoping University (Faculty Grant SFO Mat LiU) [2009 00971]

    Available from: 2023-04-12 Created: 2023-04-12 Last updated: 2023-11-09
    Download full text (pdf)
    fulltext
    Download (png)
    presentationsbild