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  • Hardell, Henrik
    et al.
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Kommunikations- och transportsystem. Linköpings universitet, Tekniska fakulteten. Airspace Unit, Luftfartsverket (LFV), 60179, Norrköping, Sweden.
    Otero, Evelyn
    Department of Engineering Mechanics, Royal Institute of Technology (KTH), 10044, Stockholm, Sweden.
    Polishchuk, Tatiana
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Kommunikations- och transportsystem. Linköpings universitet, Tekniska fakulteten.
    Smetanová, Lucie
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Kommunikations- och transportsystem. Linköpings universitet, Tekniska fakulteten.
    Optimizing air traffic management through point merge procedures: Minimizing delays and environmental impact in arrival operations2025Ingår i: Journal of Air Transport Management, ISSN 0969-6997, E-ISSN 1873-2089, Vol. 123, artikel-id 102706Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We present an application of a mixed-integer programming (MIP) framework for automatic traffic synchronization, providing safe separation between the arriving traffic within the terminal maneuvering area (TMA) of an airport implementing point merge (PM) procedures. Additionally, the proposed methodology ensures conflict-free operations when departures and arrivals share a common runway. Based on real traffic scenarios for two European airports, we model realistic descent profiles and assume all the arrivals are performing the most fuel-efficient continuous descent operations (CDOs). We compare two scenarios: in the first, the arriving aircraft are strictly forced to adhere to the published arrival route structures, meaning that a turn towards the merge point may not be initiated prior to reaching the point merge system (PMS), while in the second scenario, aircraft may be assigned a shortcut from a published waypoint along the arrival route. We evaluate the resulting arrival flight efficiency and compare it to that of the actual flights, arriving during the hour selected for our optimization, noticing varying benefits for the two airports and whether shortcuts are allowed or not. Given the correct setting for the specific airport, we demonstrate that our approach provides significant benefits, including increased vertical performance as well as reduced time and distance, contributing to lower levels of noise and fuel savings, accompanied by reduced emissions.

     

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  • Disputation: 2025-01-22 10:15 Ada Lovelace, LinköpingBeställ onlineKöp publikationen >>
    Zhou, Jian
    Linköpings universitet, Institutionen för systemteknik, Fordonssystem. Linköpings universitet, Tekniska fakulteten.
    Context-Aware Predictive Motion Planning for Safe Autonomous Driving2024Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    In a predictive motion-planning strategy, the autonomous ego vehicle needs to predict the motion of surrounding obstacles and use predictions to plan collision-free reference trajectories. In multi-vehicle traffic environments, a key research question is how to consider vehicle-to-vehicle interactions, behavior uncertainties, and environmental influence on the motion of surrounding obstacles to achieve resilient motion planning of the autonomous ego vehicle. This thesis proposes context-aware motion-planning methods for autonomous driving in uncertain and dynamic environments, and makes several contributions to design motion-planning strategies with the desired performance.

    The first contribution is designing an interaction-aware moving target model predictive control (MPC). This method is formulated based on integrating an interaction-aware motion-prediction model and time-varying reference targets of the receding-horizon optimal control problem for proactive and non-local trajectory planning in multi-vehicle dynamic traffic scenarios.

    For the second contribution, the proposed interaction-aware moving target MPC planner is extended to account for the multi-modal motion uncertainties of surrounding vehicles, including both the maneuver and trajectory uncertainties. Based on the modeling of uncertainties, a safety-awareness parameter is designed to compute the obstacle occupancy to achieve a trade-off between the performance and robustness of the motion planner.

    The third contribution is learning motion uncertainties of obstacles to reduce the conservativeness of the motion planner while pursuing robustness. To this end, a robust motion-planning method is designed for autonomous driving systems based on learning the unknown control set of dynamic obstacles. The learned control set is then applied to predict the reachable set of obstacles to formulate a collision-avoidance constraint. The effectiveness of the method is validated in hardware experiments involving reach-avoid planning problems for mobile robots, and in simulations of autonomous forced merging that incorporates both decision-making and trajectory planning.

    The fourth contribution is an environment-aware motion-planning strategy, where the method achieves environment awareness by predicting sensible maneuvers of surrounding vehicles considering road-geometry constraints. By considering environmental factors, the method effectively predicts the forward reachability of surrounding vehicles, which is applied to formulate collision-avoidance constraints in the motion-planning problem. The performance of the proposed strategy is demonstrated through both simulations in roundabout scenarios and hardware experiments with car-like mobile robots.

    This thesis demonstrates that autonomous vehicles can perform safe and efficient motion planning under uncertainties based on context awareness.

    Delarbeten
    1. Interaction-Aware Moving Target Model Predictive Control for Autonomous Vehicles Motion Planning
    Öppna denna publikation i ny flik eller fönster >>Interaction-Aware Moving Target Model Predictive Control for Autonomous Vehicles Motion Planning
    2022 (Engelska)Ingår i: 2022 EUROPEAN CONTROL CONFERENCE (ECC), IEEE , 2022, s. 154-161Konferensbidrag, Publicerat paper (Refereegranskat)
    Abstract [en]

    This paper investigates an integrated traffic environment modeling and model predictive control (MPC) system to realize interaction-aware dynamic motion planning of an autonomous vehicle with multiple surrounding vehicles. The interaction-aware interacting multiple model Kalman filter (IAIMM-KF) from the literature is used to hierarchically predict maneuvers and trajectories of surrounding vehicles and to compute safe targets for the ego vehicle. The targets are terminal speed and reference lane, which are moving targets as they are updated at each time step. Then, an MPC controller is designed for the ego vehicle to generate an optimal trajectory by following the moving targets and including the prediction results to formulate collision-free constraints. The proposed interaction-aware planning method has a proactive planning ability and can avoid collisions by non-local replanning. The strengths and effectiveness of the approach are verified in challenging highway lane-change simulation scenarios.

    Ort, förlag, år, upplaga, sidor
    IEEE, 2022
    Nationell ämneskategori
    Robotteknik och automation
    Identifikatorer
    urn:nbn:se:liu:diva-189502 (URN)10.23919/ECC55457.2022.9838002 (DOI)000857432300019 ()9783907144077 (ISBN)9781665497336 (ISBN)
    Konferens
    European Control Conference (ECC), London, ENGLAND, jul 12-15, 2022
    Anmärkning

    Funding Agencies|Strategic Research Area at Linkoping-Lund in Information Technology (ELLIIT); Wallenberg AI, Autonomous Systems and Software Program (WASP) - Knut and Alice Wallenberg Foundation

    Tillgänglig från: 2022-10-25 Skapad: 2022-10-25 Senast uppdaterad: 2024-12-02
    2. Interaction-Aware Motion Planning for Autonomous Vehicles With Multi-Modal Obstacle Uncertainty Predictions
    Öppna denna publikation i ny flik eller fönster >>Interaction-Aware Motion Planning for Autonomous Vehicles With Multi-Modal Obstacle Uncertainty Predictions
    2024 (Engelska)Ingår i: IEEE Transactions on Intelligent Vehicles, ISSN 2379-8858, E-ISSN 2379-8904, Vol. 9, nr 1, s. 1305-1319Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    This article proposes an interaction and safety-aware motion-planning method for an autonomous vehicle in uncertain multi-vehicle traffic environments. The method integrates the ability of the interaction-aware interacting multiple model Kalman filter (IAIMM-KF) to predict interactive multi-modal maneuvers of surrounding vehicles, and the advantage of model predictive control (MPC) in planning an optimal trajectory in uncertain dynamic environments. The multi-modal prediction uncertainties, containing both the maneuver and trajectory uncertainties of surrounding vehicles, are considered in computing the reference targets and designing the collision-avoidance constraints of MPC for resilient motion planning of the ego vehicle. The MPC achieves safety awareness by incorporating a tunable parameter to adjust the predicted obstacle occupancy in the design of the safety constraints, allowing the approach to achieve a trade-off between performance and robustness. Based on the prediction of the surrounding vehicles, an optimal reference trajectory of the ego vehicle is computed by MPC to follow the time-varying reference targets and avoid collisions with obstacles. The efficiency of the method is illustrated in challenging highway-driving simulation scenarios and a driving scenario from a recorded traffic dataset.

    Ort, förlag, år, upplaga, sidor
    Institute of Electrical and Electronics Engineers (IEEE), 2024
    Nationell ämneskategori
    Reglerteknik
    Identifikatorer
    urn:nbn:se:liu:diva-193650 (URN)10.1109/TIV.2023.3314709 (DOI)001173317800113 ()
    Anmärkning

    Funding Agencies|Strategic Research Area at Linkoping-Lund in Information Technology (ELLIIT)

    Tillgänglig från: 2023-05-11 Skapad: 2023-05-11 Senast uppdaterad: 2024-12-02Bibliografiskt granskad
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  • Nylander, Erik
    Linköpings universitet, Institutionen för beteendevetenskap och lärande, Pedagogik och vuxnas lärande. Linköpings universitet, Utbildningsvetenskap.
    A bibliometric study of Swedish educational research: mapping key themes, 2000–20202024Ingår i: Scandinavian Journal of Educational Research, ISSN 0031-3831, E-ISSN 1470-1170Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This article maps the landscape of Swedish educational research as it has been published over the period 2000–2020 in peer-reviewed English language journals. Topic modeling techniques were used to analyze the metadata of keywords, abstracts, and titles from 7,402 peer-reviewed articles in the Scopus database. This analysis identified 25 topics characteristic of Swedish educational research. Analysis of supplementary bibliographic information, including reference lists, authorship, and journal titles, reveals that qualitative studies on teaching and learning, particularly those using phenomenographic, pragmatic, and socio-cultural/activity theory approaches, have dominated Swedish educational research. The article concludes by examining the content of this body of knowledge along key axes of contestation. Research on skills and competences often employs a markedly different language than studies focusing on values and attitudes. Furthermore, research centered on learning and didactics as a microphenomenon contrasts with work that emphasizes educational organization and large-scale evaluation.

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  • Zuccotti, Pao
    Linköpings universitet, Institutionen för tema, Tema Genus.
    Eugenic Hauntings: Colonial Affective Orientations and the Struggle for Queer Sámi Sovereignty2024Självständigt arbete på avancerad nivå (masterexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    This thesis uncovers and investigates the colonial affective orientations that oppose queer Sámi sovereignty in Sápmi-Sweden. I draw on theoretical frameworks from queer and trans Indigenous studies and Sara Ahmed’s theories of orientation—specifically, the directedness of feelings and affects shaping embodied ways of valuing, meaning-making, and relating to lifeworlds. Through an anticolonial affective textual analysis, I trace how these orientations sediment in systemic and infrastructural practices. I demonstrate how they function to secure settler futures, or produce and naturalize settler spatiotemporal formations, by examining the entanglement of Euro-gendering and familism with science (Linnaeus and eugenics), Christianity (Laestadius), and the nation-state (Folkhem). My positionality as a white gender-nonconforming settler informs my approach, as I work to suspend my desires to know and extract from Indigeneity while navigating and unlearning colonial cis-heteronormative frameworks. In the analysis, I find that settler colonial orientations direct affects and emotions in ways that subjectivize, discipline, and exploit bodies and lands. These orientations reflect a need, desire, and patronizing imperative to domesticate and cultivate the ungendered and immature body land. Settler colonial relations are normalized and perpetuated through vocational duties to align with heteropatriarchal family structures. In parallel, the settler colonial aim to eliminate Indigenous peoples and indigenize whiteness is sustained by an unrelenting quest for racialized and ableist gender/sexual purity. Ultimately, these affective orientations naturalize settler colonialism through a system of promises and non-promises: the promise of security of familial love to productive members of society and the non-promise of exploitation to the unproductive. When interrogating how Christianization, eugenics, and national-productivist welfare converge to render settler colonialism invisibilized in Sweden, eugenic and settler colonial biopolitical ideologies emerge as irremediably interlocked. The specter of eugenics continues to haunt settler-Sámi relations, urging further investigation into settler colonial affective economies while also acknowledging the orientations that nurture queer Sámi resurgence and sovereignty.

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    Eugenic Hauntings - Colonial Affective Orientations and the Struggle for Queer Sámi Sovereignty - Pao Zuccotti
  • Pilevång Bergqvist, Emma
    Linköpings universitet, Institutionen för tema.
    Queering Beyond the Invisible: – An Exploratory Study of the Experiences of Neurodivergent Queer Individuals in Swedish Reports2024Självständigt arbete på avancerad nivå (masterexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
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    Queering Beyond the Invisible
  • Disputation: 2025-01-16 09:00 Berzeliussalen, Building 463, LinköpingBeställ onlineKöp publikationen >>
    Chanthongdee, Kanat
    Linköpings universitet, Institutionen för biomedicinska och kliniska vetenskaper, Centrum för social och affektiv neurovetenskap. Linköpings universitet, Medicinska fakulteten.
    Epigenetic Mechanisms underlying Alcohol Dependence and Fear Memories2025Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Stress is a critical factor in the onset and progression of alcohol dependence, a chronic condition characterized by loss of control over alcohol drinking. Stress is also a major risk factor for other psychiatric disorders, such as anxiety disorders. Alcohol dependence and anxiety disorders share overlapping neuroadaptations, in part mediated by epigenetic mechanisms. We have previously demonstrated that chronic alcohol exposure induces DNA hypermethylation in the dorsomedial prefrontal cortex (dmPFC) in rats. In a follow-up study, our group reported that alcohol-induced hypermethylation reduces the expression of the histone methyltransferase PRDM2, which in turn promotes stress-induced reinstatement of alcohol. These findings point to undiscovered contributions of PRDM2 to stress responses.

    This thesis aimed to further understand the role of PRDM2 in stress-induced maladaptive behaviors. Study 1 showed that decreased Prdm2 expression in the dmPFC-basolateral amygdala (BLA) projection resulted in an over-consolidation of fear memory through upregulated glutamatergic signaling. Study 2 showed that decreased PRDM2 activity promotes footshock-induced relapse-like behavior in both male and female rats. Together, these findings suggest that PRDM2 may be a shared molecular substrate between alcohol dependence and anxiety disorder. Downregulation of Prdm2 in the dmPFC-BLA projection did not impact stress-induced reinstatement, while decreased Prdm2 in the dmPFC-nucleus accumbens core projection promoted reinstatement. Consistent with our preclinical findings, Study 2 also found that people with alcohol dependence exhibited reduced PRDM2 expression and increased methylation at its promoter in the prefrontal cortex. This suggests that PRDM2 and its regulatory mechanisms have a mechanistic role in stress responses, and serve as epigenetic markers for alcohol dependence across species.

    In both Study 1 and Study 2, we observed a broad range of defensive behaviors in rats. Therefore, in Study 3, an ethological analysis was performed to identify multiple behaviors in response to threat-associated cues. We also assessed the utility of a machine learning pipeline to perform ethological analysis. The approach from Study 3 was implemented in Study 4, in which patterns of behaviors were characterized among rats observing a conspecific undergoing fear conditioning. Heightened fear in the observer rats associated with increased neural activation in several areas, including the dmPFC. However, the increased dmPFC activity and the heightened vicarious fear were not mediated by decreased Prdm2 expression. This suggests that direct and observational fear learning in part rely on distinct molecular mechanisms. Collectively, this thesis highlights the importance of PRDM2 and its behavioral- and circuit-specific effect in mediating fear- and alcohol-associated behaviors.  

    Delarbeten
    1. An epigenetic mechanism for over-consolidation of fear memories
    Öppna denna publikation i ny flik eller fönster >>An epigenetic mechanism for over-consolidation of fear memories
    Visa övriga...
    2022 (Engelska)Ingår i: Molecular Psychiatry, ISSN 1359-4184, E-ISSN 1476-5578, Vol. 27, nr 12, s. 4893-4904Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Excessive fear is a hallmark of anxiety disorders, a major cause of disease burden worldwide. Substantial evidence supports a role of prefrontal cortex-amygdala circuits in the regulation of fear and anxiety, but the molecular mechanisms that regulate their activity remain poorly understood. Here, we show that downregulation of the histone methyltransferase PRDM2 in the dorsomedial prefrontal cortex enhances fear expression by modulating fear memory consolidation. We further show that Prdm2 knock-down (KD) in neurons that project from the dorsomedial prefrontal cortex to the basolateral amygdala (dmPFC-BLA) promotes increased fear expression. Prdm2 KD in the dmPFC-BLA circuit also resulted in increased expression of genes involved in synaptogenesis, suggesting that Prdm2 KD modulates consolidation of conditioned fear by modifying synaptic strength at dmPFC-BLA projection targets. Consistent with an enhanced synaptic efficacy, we found that dmPFC Prdm2 KD increased glutamatergic release probability in the BLA and increased the activity of BLA neurons in response to fear-associated cues. Together, our findings provide a new molecular mechanism for excessive fear responses, wherein PRDM2 modulates the dmPFC -BLA circuit through specific transcriptomic changes.

    Ort, förlag, år, upplaga, sidor
    Springer Nature, 2022
    Nationell ämneskategori
    Neurovetenskaper
    Identifikatorer
    urn:nbn:se:liu:diva-189083 (URN)10.1038/s41380-022-01758-6 (DOI)000855637600001 ()36127428 (PubMedID)2-s2.0-85138397577 (Scopus ID)
    Anmärkning

    Funding Agencies|Swedish Research Council [2013-07434]; Region ostergotland; Stiftelsen Psykiatriska Forskningsfonden; Wallenberg Foundation; Knut och Alice Wallenberg Stiftelse Grant; Knut and Alice Wallenberg Foundation

    Tillgänglig från: 2022-10-11 Skapad: 2022-10-11 Senast uppdaterad: 2024-11-28
    2. Comprehensive ethological analysis of fear expression in rats using DeepLabCut and SimBA machine learning model
    Öppna denna publikation i ny flik eller fönster >>Comprehensive ethological analysis of fear expression in rats using DeepLabCut and SimBA machine learning model
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    2024 (Engelska)Ingår i: Frontiers in Behavioral Neuroscience, E-ISSN 1662-5153, Vol. 18, artikel-id 1440601Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Introduction: Defensive responses to threat-associated cues are commonly evaluated using conditioned freezing or suppression of operant responding. However, rats display a broad range of behaviors and shift their defensive behaviors based on immediacy of threats and context. This study aimed to systematically quantify the defensive behaviors that are triggered in response to threat-associated cues and assess whether they can accurately be identified using DeepLabCut in conjunction with SimBA. Methods: We evaluated behavioral responses to fear using the auditory fear conditioning paradigm. Observable behaviors triggered by threat-associated cues were manually scored using Ethovision XT. Subsequently, we investigated the effects of diazepam (0, 0.3, or 1 mg/kg), administered intraperitoneally before fear memory testing, to assess its anxiolytic impact on these behaviors. We then developed a DeepLabCut + SimBA workflow for ethological analysis employing a series of machine learning models. The accuracy of behavior classifications generated by this pipeline was evaluated by comparing its output scores to the manually annotated scores. Results: Our findings show that, besides conditioned suppression and freezing, rats exhibit heightened risk assessment behaviors, including sniffing, rearing, free-air whisking, and head scanning. We observed that diazepam dose-dependently mitigates these risk-assessment behaviors in both sexes, suggesting a good predictive validity of our readouts. With adequate amount of training data (approximately > 30,000 frames containing such behavior), DeepLabCut + SimBA workflow yields high accuracy with a reasonable transferability to classify well-represented behaviors in a different experimental condition. We also found that maintaining the same condition between training and evaluation data sets is recommended while developing DeepLabCut + SimBA workflow to achieve the highest accuracy. Discussion: Our findings suggest that an ethological analysis can be used to assess fear learning. With the application of DeepLabCut and SimBA, this approach provides an alternative method to decode ongoing defensive behaviors in both male and female rats for further investigation of fear-related neurobiological underpinnings.

    Ort, förlag, år, upplaga, sidor
    FRONTIERS MEDIA SA, 2024
    Nyckelord
    fear conditioning; ethological analysis; risk-assessment; DeepLabCut; SimBA
    Nationell ämneskategori
    Neurovetenskaper
    Identifikatorer
    urn:nbn:se:liu:diva-207206 (URN)10.3389/fnbeh.2024.1440601 (DOI)001291617500001 ()39148895 (PubMedID)
    Anmärkning

    Funding Agencies|Swedish Research Council [2013-07434]; Stiftelsen Psykiatriska Forskningsfonden; Wallenberg Foundation; Knut och Alice Wallenberg Stiftelse Grant

    Tillgänglig från: 2024-09-04 Skapad: 2024-09-04 Senast uppdaterad: 2024-11-28
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  • Jørgensen, Laus Damgaard
    Linköpings universitet, Institutionen för kultur och samhälle.
    Mothers' Groups for Newcomers and Ethnic Minorities in Denmark: Active Citizenship, Inclusion, and Well-being2024Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    This thesis sets out to discuss the sometimes-contradictory elements of the Danish integration policy and the development of active citizenship in the early 2000s that positions the migrant as having neglected their obligation, or duty, to contribute towards the Danish society, especially through labour market participation. Active citizenship, a political rhetoric born out of frustration with the lack of engagement with Danish society and employment amongst migrant groups giving birth to increasingly restrictive and punitive migration and integration policies. In contrast to this, there have been established mothers' groups for newcomers and ethnic minorities by individual district nurses since the late 70s with the goals of simultaneously providing new mothers with a social space to combat isolation and depression, improve their parenting skills, boost their confidence, act as a stepping stone towards other institutions, and education and employment for the women. Through this, some or many of the mothers became motivated to improve their Danish language, enrol in education, or take on employment. The mothers' groups in this way improve the active citizenship of the mothers, but it is not seen as the goal but as an outcome of the mothers' improved well-being and further, it is seen as a tool to improve their independence and agency of the mothers over their own lives. Through interviews with three mothers' groups for newcomers and ethnic minorities and one interview with an international mothers' group, the thesis concludes that the mothers' groups, though not quantifiable, can manage to improve the integration of the mothers in the aspects of institutional and social inclusion by improving their feeling of belonging in Denmark. This is particularly done through a focus on democratic processes of expansive learning to support their well-being, allowing for cultural differences, and mitigating conflicting expectations understood as structural double-binds. However, the groups still have their own agendas of what they want the mothers to focus on, aspects such as contraception and employability, which can potentially act as cases of implicit governing if the participants are not aware of or able to resist such agendas. The mothers' groups overall can act as a counter-point to existing Danish migration and integration policy that in many cases focuses on punitive measures and deportation that themselves negatively affect integration efforts. The thesis adds to existing research on integration, parenting, and parent programs amongst newcomers and ethnic minorities in Denmark.

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    Laus - Master's Thesis - Mothers' Groups for Newcomers and Ethnic Minorities in Denmark
  • Zardan Burgos, Paola
    Linköpings universitet, Institutionen för hälsa, medicin och vård.
    Kommunikation och samspel vid måltider hos barn med selektivt ätande och autismspektrumtillstånd2024Självständigt arbete på avancerad nivå (masterexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Studien syftar till att undersöka kommunikation och samspel mellan barn med selektivt ätande (SÄ) och autismspektrumtillstånd (AST) och deras vårdnadshavare vid måltidssituationer. Fokus ligger på interaktionen mellan barnet och omgivande personer, inklusive kommunikativa barriärer och beteenden, samt anpassningar som underlättar samspelet. Två olika typer av datainsamling och två analysmetoder tillämpades. Intervjuer med vårdnadshavare genomfördes och analyserades med hjälp av tematisk analys. Videoinspelningar av måltidssituationer i hemmet analyserades genom konversationsanalys. Den tematiska analysen resulterade i fyra teman: 1) utmaningar vid måltidssituationer, 2) verbal och icke-verbal kommunikation utan hjälpmedel, 3) användning av analoga och digitala verktyg som alternativ och kompletterande kommunikation (AKK), samt 4) faktorer som förbättrar ätande och samspel. Utifrån konversationsanalysen framträdde två fenomen i interaktionen under måltidssituationerna: direktiv och skratt. Vårdnadshavarnas direktiv handlade om att uppmuntra barnen att äta ny mat eller delta vid måltiden. Direktiven uttrycktes verbalt och icke-verbalt, anpassat efter barnens respons och beteende. Skratt uppstod både enskilt och kollektivt och fyllde olika funktioner, såsom att skratta åt andra, dela humor samt uttrycka känslor. Studiens fynd visar att kommunikationen mellan vårdnadshavare och barn med SÄ och AST är komplex och varierar beroende på individ och miljö. Förväntningar från vårdnadshavare på barnens beteende vid måltidssituationer kan leda till kommunikativa utmaningar även i trygga miljöer. För att förbättra barnens upplevelse vid måltider är det avgörande med anpassade och stödjande strategier, inklusive responsiv kommunikation och miljömodifieringar. Individanpassade insatser och samarbeten mellan kliniker och familjer är viktiga för att identifiera behov och möjliggöra positiva förändringar i barnens ätförmåga, kommunikation och sociala interaktioner.

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  • Tosto, Alice
    Linköpings universitet, Institutionen för tema.
    Gender Stereotypes and Their Impact on Women's Career Choices in STEM: A Case Study from Italy2024Självständigt arbete på avancerad nivå (magisterexamen), 40 poäng / 60 hpStudentuppsats (Examensarbete)
    Abstract [en]

    This research explores the influence of gender stereotypes on women’s career choices in STEM (Science, Technology, Engineering, and Mathematics) fields in Italy. Despite global efforts to increase female participation in STEM, women remain underrepresented in these fields, particularly in Italy. The study focuses on how gender stereotypes manifest in academic settings and professional careers, examining the barriers that discourage women from pursuing or continuing careers in STEM. Through a mixed-methods approach, the research collects data via a questionnaire and in-depth interviews with women who have studied STEM subjects. The survey investigates societal and institutional stereotypes, while the interviews explore the factors that lead women to abandon or avoid STEM careers. The findings reveal that pervasive gender stereotypes, structural barriers, and psychological pressures significantly impact women’s career trajectories in STEM. This study provides valuable insights into the challenges and opportunities that shape female participation in STEM fields in Italy. 

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  • Denoeud, Anne-Lise
    Linköpings universitet, Institutionen för tema, Tema Genus.
    “Unless I feel safe enough…”: Embodied experiences of friendship for 5 women of color in Sweden2024Självständigt arbete på avancerad nivå (masterexamen), 80 poäng / 120 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Drawing on critical race theory and feminist theory, this master thesis aims to explore the embodied lived experiences of friendship for 5 self-identified “women of color” in Sweden.Data were produced by 5 in-depth, semi-structured interviews to answer these research questions: in what ways does the issue of race arise in friendship? What emotions/affect are at play in the friendships experienced in Sweden by these 5 women? The data collected were analyzed through a phenomenological approach and four main themes emerged from the analysis: what “color” implies, the importance and potential for change of friendship, relational failures, and attraction to others. The findings can help acknowledge the role of race in individual interactions and work on a way to establish affective relations as a site of resistance against racism and oppression and as a driving force for social change.

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  • Stenliden, Linnéa
    et al.
    Linköpings universitet, Institutionen för beteendevetenskap och lärande, Avdelningen för lärande, estetik och naturvetenskap. Linköpings universitet, Utbildningsvetenskap.
    Sperling, Katarina
    Linköpings universitet, Institutionen för beteendevetenskap och lärande, Avdelningen för lärande, estetik och naturvetenskap. Linköpings universitet, Utbildningsvetenskap.
    Breaking the Magic of Automation and Augmentation in Swedish Classrooms2024Ingår i: Nordisk tidsskrift for pedagogikk og kritikk, E-ISSN 2387-5739, Vol. 10, nr 1, s. 15-32Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper provides a critical examination of the domain of artificial intelligence (AI) in education, with a focus on the expectations and practical implications accompanying its integration into teaching. The expectations have been propelled by two interconnected concepts: (1) the potential for AI to automate pedagogical processes, replacing teachers in certain scenarios; and (2) the notion that teachers’ insights can be augmented through AI-based analysis. Drawing on two ethnographic studies in Swedish primary and secondary schools, this paper explores the enactments of pupils, teachers and two AI-based educational technologies. The aim is to demonstrate how automation and augmentation can emerge in teachers’ practice. Utilizing inspiration from a relational epistemological problematisation of socio-technical phenomena, the paper demonstrates how rather than automation and augmentation, AI in education is an act of symmation in which automation and augmentation is co-produced by the technology and teachers’ different hidden work, in this paper conceptualised as adaptations, experimentations, compensations and confirmations. The paper suggests that the study of symmation in relation to the teaching profession can be productive in further exploring the yet limited understanding of AI in educational practice.

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  • Disputation: 2025-01-17 13:00 Hugo Theorell, 440-building, LinköpingBeställ onlineKöp publikationen >>
    Rydén, Mireille
    Linköpings universitet, Institutionen för hälsa, medicin och vård, Avdelningen för prevention, rehabilitering och nära vård. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Närsjukvården i västra Östergötland, Medicinska specialistkliniken.
    Stress, Diet and Lifestyle: Cortisol, Carotenoids, and Lifestyle Factors in a Cardiovascular Perspective2025Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Healthy lifestyle changes that may reduce the risk of cardiovascular disease are often difficult to implement in the general population. This is also true for cardiovascular patients, who usually get well-grounded advice from health professionals as well as opportunities to participate in programs to quit smoking, consume a healthier diet, reduce psychosocial stress, or increase physical activity. The reasons for this resistance and how better intervention compliance could be achieved are unclear.

    Here, the variables psychosocial stress, intake of statins, dietary habits, and sleep quality have been studied in cardiovascular patients and in a group of middle-aged individuals with respect to their role in cardiovascular disease and myocardial infarction.

    In Paper I, the aim was to investigate whether improved stress behavior in coronary artery patients with type A personality traits resulted in altered cortisol secretion after a 1-year cognitive stress management program. The stress management program, based on cognitive behavioral methods, showed a significant improvement in the patients’ ability to cope with perceived stress. However, this was not associated with any changes in diurnal cortisol secretion or levels of cholesterol or C-reactive protein. The pilot study raises questions as to the value of salivary cortisol as a stress marker in cardiac rehabilitation.

    Paper II investigated the association between diet, inflammatory markers, and carotenoid concentrations in a middle-aged population. Carotenoid levels were not solely explained by dietary intake of fruit and vegetables. Instead, significant associations were found to male sex, obesity, low levels of “protective” high-density lipoprotein cholesterol and high levels of the inflammatory marker matrix metalloproteinase-9. It can be speculated that provitamin A carotenoids have athero-protective effects.

    Paper III studied how lipid-lowering statins affect the levels of carotenoids and the inflammatory marker C-reactive protein, which could possibly participate in a cardio-protective mechanism. The study patients, with mild to moderate hypercholesterolemia, received either placebo or simvastatin and were followed up after 6 weeks. After adjustment for lipids, the levels of the carotenoids lutein, lycopene, α-carotene, and β-carotene were found to be significantly increased in the simvastatin group, suggesting an increased ratio of carotenoids per particle. Importantly, there is a risk of misinterpreting the carotenoid status in individuals on statin medication if relying on crude serum or plasma levels.

    Paper IV studied middle-aged individuals (a subgroup in the Swedish CArdioPulmonary bioImage study) with regard to adherence to a healthy diet, psychological factors (stress and sleep), and risk factors for cardiovascular disease. Dietary habits were not linked to stress or sleeping patterns. Instead, participants who lived in areas with low socioeconomic status had higher odds ratio for having more unfavorable apolipo-protein B/apolipoprotein A1 ratio. Moreover, among several predictors, depression emerged as a strong predictor of a poor lipid profile in low SES areas but not in high SES areas. This study highlighted that tailored dietary recommendations, promoting physical activity, and addressing mental health may be of particular importance in low socioeconomic status areas for cardiovascular disease risk reduction in this subgroup of patients.

    Delarbeten
    1. Does Stress Reduction Change the Levels of Cortisol Secretion in Patients With Coronary Artery Disease?
    Öppna denna publikation i ny flik eller fönster >>Does Stress Reduction Change the Levels of Cortisol Secretion in Patients With Coronary Artery Disease?
    2009 (Engelska)Ingår i: JOURNAL OF CARDIOPULMONARY REHABILITATION AND PREVENTION, ISSN 1932-7501, Vol. 29, nr 5, s. 314-317Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    PURPOSE: It has been shown that behavioral therapy has effects on Stress behavior in patients with coronary artery disease Salivary cortisol measurements are widely used to assess psychological stress, stress reactivity or both The aim of this study was to investigate whether improved stress behavior in type A patients with coronary artery disease involved changes in cortisol secretion pattern METHODS: Twenty-four male patients were identified as type A individuals and completed a 12-month cognitive-behavioral stress management program Stress behavior was evaluated by using a validated questionnaire Morning and evening salivary cortisol levels were measured over 3 consecutive clays at baseline and after 12 months. RESULTS: Although the patients showed a significant improvement in psychosocial well-being after 12 months, their basal cortisol levels of diurnal rhythm of cortisol did not change There was no Correlation between stress score and cortisol levels CONCLUSIONS. The value of salivary cortisol as both a stress marker and a new cardiovasular risk factor has been discussed but the data from this small Pilot Study raise the question of its utility as a stress marker in cardiac rehabilitation

    Nyckelord
    coronary artery disease, cortisol, stress, type A behavior
    Nationell ämneskategori
    Medicin och hälsovetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-51390 (URN)10.1097/HCR.0b013e3181ac785f (DOI)
    Tillgänglig från: 2009-10-30 Skapad: 2009-10-30 Senast uppdaterad: 2024-11-26Bibliografiskt granskad
    2. Provitamin A carotenoids are independently associated with matrix metalloproteinase-9 in plasma samples from a general population
    Öppna denna publikation i ny flik eller fönster >>Provitamin A carotenoids are independently associated with matrix metalloproteinase-9 in plasma samples from a general population
    Visa övriga...
    2012 (Engelska)Ingår i: Journal of Internal Medicine, ISSN 0954-6820, E-ISSN 1365-2796, Vol. 272, nr 4, s. 371-384Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Background and aim:  Carotenoids in plasma are inversely associated with cardiovascular risk. Low levels can be explained by low dietary intake but also by a number of other factors including inflammatory activity. Given that matrix metalloproteinase (MMP)-9 has an important role in inflammation and cardiovascular disease, we hypothesized that circulating MMP-9 levels would be inversely related to total or single carotenoids in a general population cohort. Methods:  A well-characterized population-based cohort of 285 Swedish men and women (45-69 years) was used for the present study. The intake of carotenoid-rich fruits and vegetables was estimated from a food frequency questionnaire. Levels of MMP-9, C-reactive protein (CRP), interleukin (IL)-6 and six major carotenoids [β-cryptoxanthine, α-carotene, β-carotene, lutein (+ zeaxanthin) and lycopene] were determined in plasma. Results:  Lower plasma levels of total and single carotenoids were associated with lower dietary intake of carotenoids, older age, male sex, lower physical activity, higher alcohol consumption, higher body mass index (BMI), higher systolic and diastolic blood pressures, lower levels of total cholesterol and HDL cholesterol and higher levels of CRP, IL-6 and MMP-9. After multivariate adjustments, plasma levels of total carotenoids and provitamin A carotenoids (β-cryptoxanthine, α-carotene and β-carotene) remained independently associated with sex, dietary intake of carotenoids, BMI, HDL cholesterol and MMP-9, while associations with CRP and IL-6 were not maintained. Neither dietary intake of carotenoid-rich fruits and vegetables, nor vitamin supplement use was associated with MMP-9, CRP or IL-6 levels. Conclusion:  Plasma carotenoids were associated with a variety of factors including age, sex, dietary intake and metabolic variables. A new finding was the independent relationship in plasma between low provitamin A carotenoids and high MMP-9, suggesting a link between these carotenoids, matrix turnover and arterial remodelling. © 2012 The Association for the Publication of the Journal of Internal Medicine.

    Ort, förlag, år, upplaga, sidor
    Wiley-Blackwell, 2012
    Nyckelord
    CMOS, photon counting, spectral computed tomography, x-ray detection
    Nationell ämneskategori
    Medicin och hälsovetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-75982 (URN)10.1111/j.1365-2796.2012.2534x.x (DOI)000308877500005 ()22372952 (PubMedID)
    Anmärkning

    funding agencies|Swedish Heart-Lung Foundation||Swedish Research Council||Linkoping University||

    Tillgänglig från: 2012-03-21 Skapad: 2012-03-21 Senast uppdaterad: 2024-11-26
    3. Effects of simvastatin on carotenoid status in plasma
    Öppna denna publikation i ny flik eller fönster >>Effects of simvastatin on carotenoid status in plasma
    2012 (Engelska)Ingår i: NMCD. Nutrition Metabolism and Cardiovascular Diseases, ISSN 0939-4753, E-ISSN 1590-3729, Vol. 22, nr 1, s. 66-71Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    BACKGROUND AND AIMS: Carotenoids are potent antioxidants mainly transported in the low density lipoprotein (LDL) fraction. They may also influence the immune response and inverse associations with inflammatory markers have been reported. We investigated whether simvastatin, by exerting both lipid-lowering and anti-inflammatory effects, altered the carotenoid status in plasma.

    METHODS AND RESULTS: A randomized, double-blind, placebo-controlled study design was applied. Eighty volunteers with mild to moderate hypercholesterolemia received either simvastatin 40 mg or placebo for 6 weeks. Lipids, oxidized LDL (ox-LDL), C-reactive protein (CRP), interleukin (IL)-6, oxygenated carotenoids (lutein, zeaxanthin, beta-cryptoxanthin) and hydrocarbon carotenoids (alpha-carotene, beta-carotene, lycopene) were measured in plasma. Simvastatin use was associated with significant reductions in total cholesterol, LDL, ox-LDL and CRP. Simvastatin therapy also resulted in reduced plasma levels of both oxygenated and hydrocarbon carotenoids. However, when adjusted for lipids, all carotenoids except beta-cryptoxanthin showed significant increases after simvastatin therapy. Both crude and lipid-adjusted carotenoids were inversely correlated with CRP and IL-6 in plasma but the change in carotenoid status during simvastatin therapy was not specifically related to any changes in inflammatory markers.

    CONCLUSIONS: To summarize, the change in carotenoid status during simvastatin therapy was mainly attributed to the lowering of cholesterol and not to the suppression of inflammatory activity. After adjustment for lipids, the levels of lutein, lycopene, alpha-carotene and beta-carotene were significantly increased by simvastatin suggesting an increased ratio of carotenoids per particle.

    Ort, förlag, år, upplaga, sidor
    Elsevier, 2012
    Nyckelord
    Statin; Carotenoid; Lipid; Lipoprotein; Inflammation
    Nationell ämneskategori
    Kardiologi
    Identifikatorer
    urn:nbn:se:liu:diva-59339 (URN)10.1016/j.numecd.2010.04.009 (DOI)000298325000010 ()20678906 (PubMedID)2-s2.0-83855165827 (Scopus ID)
    Anmärkning

    Funding agencies|Swedish Heart-Lung Foundation||

    Tillgänglig från: 2010-09-13 Skapad: 2010-09-13 Senast uppdaterad: 2024-11-26Bibliografiskt granskad
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  • Gimstedt, Hanna
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Malmstens Linköpings universitet.
    Kostymen sys i det tysta: En undersökning av den textila artefaktens potential i dödens rituella rum2024Självständigt arbete på grundnivå (kandidatexamen), 10,5 poäng / 16 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    ”Kostymen sys i det tysta”,  är en undersökning av den textila artefaktens roll i dödsritualer (såsom begravningar och minnestunder) och hur den kan öka ritualens performativa verkan hos deltagarna samt ge dem en ökad agens i det rituella rummet. Förutom frågeställningen tar arbetet avstamp i ett antal intuitivt formulerade hypoteser som vuxit fram i min hantverkspraktik. De berör textiliernas relationella egenskaper, deras potential att erbjuda de deltagande i ritualen ett större utrymme för fysiskt engagemang samt de biologiskt nedbrytbara materialens möjlighet att i en rituell kontext minska det existentiella avståndet mellan människan och den fysiska världen omkring henne.

    Metoderna är flera: dels tillverkningen av en fysisk gestaltning i form av en begravningskista helt i mjuka, biologiskt nedbrytbara material – en textil rituell artefakt vars normbrytande karaktär blottlägger de gränsdragningar som finns i det samtida rituella rummet. Den är tillverkad med tekniker hämtade från traditionell möbeltapetsering i en utforskande, experimentell och intuitiv process. Den andra metoden är att genom litteraturstudier och samtal ge gestaltningen en såväl historisk som samtida kontext. Dessa metoder står i dialog med varandra genom projektet, vilket utmynnar i skrivandet av denna text. Skrivandet är i sig är en tredje metod: att lägga samman de teoretiska och de praktiska perspektiven och sätta ord på dem är slutfasen av det sökande efter egen förståelse för vad projektet egentligen handlar om: vad behovet att göra min egen kista bottnar i, att utövandet av ett hantverk har mycket gemensamt med rituella praktiker, och att en mer levande dödskultur kan ha betydelse för människors värderingar och vilja att ställa om till ett hållbart sätt att leva. 

    Utifrån dessa både teoretiska, praktiska och konstnärliga undersökningar landar jag i slutsatsen att textila artefakter kan ha potential att förstärka den rituella upplevelsen hos de sörjande, förutsatt att textilierna laddas med betydelse genom exempelvis koppling bakåt i historien. Det krävs också en kroppslig interaktion med artefakten inom ramen för ritualen. Ritualens performativa funktion – dess möjlighet att innebära en förvandling för deltagande kroppar, levande och döda – kan alltså få mer kraft genom ett ökat inslag av textila artefakter. 

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  • Andersson, Per
    et al.
    Linköpings universitet, Institutionen för beteendevetenskap och lärande, Pedagogik och vuxnas lärande. Linköpings universitet, Utbildningsvetenskap.
    Ahn, Song-ee
    Linköpings universitet, Institutionen för beteendevetenskap och lärande, Pedagogik och vuxnas lärande. Linköpings universitet, Utbildningsvetenskap.
    Köpsén, Johanna
    Linköpings universitet, Institutionen för beteendevetenskap och lärande, Pedagogik och sociologi. Linköpings universitet, Filosofiska fakulteten.
    Editorial: Spring 20242024Ingår i: Nordic Journal of Vocational Education and Training, E-ISSN 2242-458X, Vol. 14, nr 1, s. iii-vArtikel i tidskrift (Övrigt vetenskapligt)
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  • Disputation: 2025-01-24 14:00 TEMCAS, LinköpingBeställ onlineKöp publikationen >>
    Anatoli, Olga
    Linköpings universitet, Institutionen för tema, Tema Barn. Linköpings universitet, Filosofiska fakulteten.
    Being and Becoming a Bilingual Preschooler: A Co-Operative Action Approach to Bilingual Early Childhood Education and Care2025Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    Denna sammanläggningsavhandling handlar om barns deltagande och möjligheter till tvåspråkigt lärande i en svensk-engelska förskola. Teoretiskt bygger avhandlingen på ett perspektiv på samskapande i utveckling av tvåspråkighet och tillämpar multimodal konversationsanalys. Data består av 80 timmar videoetnografiska inspelningar av vardagliga aktiviteter som äger rum i en tvåspråkig förskola i Sverige. Avhandlingen syftar till att undersöka hur barns delaktighet och inflytande manifesterar sig i en tvåspråkig förskola, och hur vardagliga institutionella interaktioner i förskolan bidrar till barns tvåspråkiga lärande. Avhandlingen består av tre separata empiriska delstudier som utgår från följande specifika forskningsfrågor: Hur initierar barn interaktioner med lärare och hur uppmärksammas och bemöts sådana initiativ av lärare och andra barn? Hur leder vardagliga aktiviteter till att utforska ordets betydelse på två språk och hur är ordförrådsfokuserade sekvenser organiserade i den tvåspråkiga förskolemiljön? Vilka möjligheter till tvåspråkigt lärande skapas genom lärares verbala och förkroppsligade instruktioner samt barns deltagande i vardagliga uppgifter? De empiriska delstudierna presenterar följande resultat: möjligheter till tvåspråkig undervisning och lärande fördelas genom vardagliga, omsorgsinriktade aktiviteter; barns tvåspråkighet är observerbar i deras dagliga interaktioner med olika samtalspartners samt i relation till förskolans språkpolicy. Studierna visar (i) hur barn genom sina sätt att inleda samtal med lärare möjliggjorde att de kunde utveckla sina tvåspråkiga och interaktionella färdigheter; (ii) hur barn och lärare genom samarbete upptäckte tvåspråkiga betydelser i flerpartssamtal; och (iii) hur lärare modellerade språkanvändning när de vägledde barn i att utföra praktiska uppgifter och hur barns förkroppsligade handlingar visade deras förståelse för tvåspråkiga instruktioner. Avhandlingen bidrar till forskning om barns deltagande i den tvåspråkiga institutionella miljön genom att synliggöra hur barn och lärare använder multimodala semiotiska resurser i dialogiska interaktioner, och hur dessa interaktioner skapar möjligheter för barns språkinlärning. Med fokus på lärar- och barnsamverkan belyser denna avhandling barns delaktighet och handlingsfrihet genom samskapande aktiviteter.

    Delarbeten
    1. Child-initiated informings and conversational participation in a bilingual preschool
    Öppna denna publikation i ny flik eller fönster >>Child-initiated informings and conversational participation in a bilingual preschool
    2023 (Engelska)Ingår i: Journal of Pragmatics, ISSN 0378-2166, E-ISSN 1879-1387, Vol. 217, s. 33-48Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    This paper explores children's interactional competence in the context of bilingual early childhood education, looking specifically at how very young children initiate conversations with teachers by informing them about something interesting and new. Video recordings collected from ethnographic fieldwork in a Swedish–English preschool are investigated from the conversation analytic perspective, paying particular attention to multimodal aspects of naturally-occurring interactions. The analysis reveals that in initiating informings aimed at teachers in a multiparty institutional setting, children practice their bilingual skills in turn-taking and recipient design, and present their topic as relevant and coherent within the local material and conversational context. In so doing, children navigate institutional constraints on participation, secure teachers' recipiency, and establish themselves as knowledgeable speakers. Child-initiated participation in multiparty institutional settings provides a co-operative, transformative social process that constitutes an essential affordance for children's development of interactional competence in a bilingual educational context.

    Ort, förlag, år, upplaga, sidor
    Elsevier, 2023
    Nyckelord
    Adult-child interaction; Bilingualism; Early childhood education; Interactional competence
    Nationell ämneskategori
    Pedagogik
    Identifikatorer
    urn:nbn:se:liu:diva-197995 (URN)10.1016/j.pragma.2023.09.007 (DOI)001150119800001 ()2-s2.0-85171469850 (Scopus ID)
    Tillgänglig från: 2023-09-21 Skapad: 2023-09-21 Senast uppdaterad: 2024-11-25Bibliografiskt granskad
    2. Swedish-English preschool as a site for the collaborative discovery of bilingual meanings
    Öppna denna publikation i ny flik eller fönster >>Swedish-English preschool as a site for the collaborative discovery of bilingual meanings
    2024 (Engelska)Ingår i: Journal of Early Childhood Education Research, E-ISSN 2323-7414, Vol. 13, nr 1, s. 92-121Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    This paper examines spontaneous conversations about word meaning in a bilingual preschool in Sweden. This qualitative empirical study is grounded in an ethnomethodological theoretical framework and contributes to research on multilingualism by using a sociocultural lens to examine mundane linguistic experiences of very young children who learn to speak in more than one language. The data comprise video-recordings of naturally occurring interactions among teachers and children in a Swedish-English preschool with a one teacher-one language policy. The data were collected during ethnographic fieldwork in an urban area in Sweden. Approached with multimodal interactional analysis, the data draw attention to teachers’ everyday didactics, including their professional strategies for initiating spontaneous vocabulary work and orchestrating multiparty engagement in the collaborative discovery of meaning, and children’s participation. The analysis discusses strategies for providing word definitions and demonstrates mundane institutional contexts outside of the classroom setting where such interactions were possible. Both teachers and children engaged in vocabulary exploration by using words in a situated, locally meaningful way. The study highlights that the teachers followed the preschool’s language policy and embodied monolingual identities, while orienting to children as multilingual learners and supporting their language development.

    Ort, förlag, år, upplaga, sidor
    Early Childhood Education Association Finland, 2024
    Nyckelord
    bilingualism, early childhood education, interaction
    Nationell ämneskategori
    Övrig annan samhällsvetenskap Lärande
    Identifikatorer
    urn:nbn:se:liu:diva-200873 (URN)10.58955/jecer.129823 (DOI)
    Tillgänglig från: 2024-02-13 Skapad: 2024-02-13 Senast uppdaterad: 2024-11-25Bibliografiskt granskad
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  • Timgren, Katja
    Linköpings universitet, Institutionen för beteendevetenskap och lärande.
    Arbete för breddat deltagande på estetisk kurs: En aktionsforskningsstudie med medverkande lärare från åtta folkhögskolor2024Självständigt arbete på avancerad nivå (magisterexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Den här studiens syfte är att i samarbete med praktiskt verksamma i folkhögskolan utveckla kunskap som kan bli användbar i folkhögskolors arbete för breddat deltagande på estetisk kurs. Forskningsfrågan handlar om vilken erfarenhetsbaserad kunskap som kan utvecklas när personal på svenska folkhögskolor, utifrån beskrivningar av hur arbete för breddat deltagande kan gå till, reflekterar över och försöker förändra situationen på de egna estetiska kurserna. Studien har genomförts som aktionsforskning. Den utgår från Deweys pragmatiska förståelse av kunskap som något som utvecklas genom reflektion över erfarenhet. Data har samlats in under en workshopverksamhet där lärare från åtta folkhögskolor har reflekterat över och försökt förändra sin verksamhet i praktiken. Insamlad data har analyserats genom en tematisk analys.

    Resultatet av studien visar att när folkhögskollärare reflekterade över och försökte förändra sin egen estetiska verksamhet utvecklades kunskap om möjliga orsaker till deltagarsammanstätningen, samt kunskap om aspekter som kan påverka förmågan att arbeta för breddat deltagande. Aspekterna var, tillgång till information och fortbildning, förmåga att gå från ord till handling, arbetstid, att vara fler i kollegiet med engagemang för breddat deltagande samt didaktiskt upplägg och förmåga att möta en bredd av deltagare. Resultatet visar också att lärare i studien kunde relatera till, och i en del fall tog steg för att överta, strategier för breddat deltagande från andra folkhögskolor. Strategierna var, möta nya målgrupper på nya platser, arrangera kulturaktiviteter där nya målgrupper besöker folkhögskolan, kontakta aktörer som redan når de grupper folkhögskolan vill nå och se över antagningsförfarandet.

    Studiens resultat kan vara användbart för folkhögskolor som vill bredda deltagandet eller för den som ska arrangera fortbildning. Studien utgör också, genom att rikta sitt fokus mot ett pågående utvecklingsarbete inom ett område där folkhögskolan står inför utmaningar, ett bidrag till forskningen om inkludering i folkhögskola.

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  • Franzén, Ellen
    Linköpings universitet, Institutionen för tema.
    Green cities: A comparative case study of urban greening in Sydney and Singapore2024Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
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  • Joy, Navya
    et al.
    Linköpings universitet, Institutionen för systemteknik.
    Labeeb, Aneesha
    Linköpings universitet, Institutionen för systemteknik.
    Single Inductor Dual-Input Dual-Output (DIDO) DC-DC Boost Converter for Energy Harvesting Applications2024Självständigt arbete på avancerad nivå (masterexamen), 28 hpStudentuppsats (Examensarbete)
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  • Disputation: 2024-12-11 10:00 Ada Lovelace, B-building, LinköpingBeställ onlineKöp publikationen >>
    Åslund, Jakob
    Linköpings universitet, Institutionen för systemteknik, Reglerteknik. Linköpings universitet, Tekniska fakulteten.
    Some unexpected behaviors of the particle filter2024Licentiatavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    The particle filter (PF) is an important tool used for estimating states in a variety of nonlinear systems, such as positioning, mapping, and diagnostics. As it is so widely used, it is important that all the properties of the PF are well understood so that practitioners can spend their efforts on the issues facing their specific application instead of on the PF.

    The PF has been in use for a long time now, and therefore much of its behavior has been figured out. At the same time, many of the core beliefs regarding the filter, such as the estimate improving when more particles are added, or marginalization always improving the estimate, are primarily based on experience rather than direct theory. While the topics have been studied, the theoretical results generally only apply as the number of particles tends to infinity and often require further assumptions of the systems being studied. This leaves room open for unexpected behaviors. In this work, analysis and explanation are given for two previously unexpected behaviors surrounding the PF.

    The first behavior studied is a counter-intuitive phenomenon where, the mean squared error (MSE) of a PF can actually increase as more particles are added. An explanation for this is provided in the form of a new property, here called ‘projected instability’. It is based on a process in which each process noise is selected to minimize the next measurement error. Extensive simulations are used to show that the phenomenon can only occur when a projected instability is present. Further analysis is provided, both to explain why this behavior can occur, and to show what other conditions have an impact on the above phenomenon occurring.

    The second result concerns the marginalized particle filter (MPF), also known as the Rao-Blackwellized particle filter (RBPF). The MPF utilizes conditionally linear substructures in the problem formulation, which allows for solving part of the estimation problem using particles, while the other part is estimated using a Kalman filter (KF) conditioned on each particle. The common understanding is that, the performance of an MPF is generally better than that of a PF with the same number of particles. What is shown here, is instead a broad subsection of problems for which the MPF gives identical quality results as the PF when applied. In fact, it is shown that after some time, the behavior of the filters is identical. Simple conditions are provided to determine when this is the case.

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  • Ludvigsson, David
    Linköpings universitet, Filosofiska fakulteten. Linköpings universitet, Institutionen för kultur och samhälle, Avdelningen för historia, konstvetenskap och religionsvetenskap.
    En meningsfull lokalhistoria? Forskning för akademi och lokalsamhälle2024Bok (Övrig (populärvetenskap, debatt, mm))
    Abstract [sv]

    Välkomna: kolleger, vänner, studenter och övriga åhörare!

    För ett par veckor sedan var jag på ett seminarium i Stockholm som anordnades av Stads- och kommunhistoriska institutet. Seminariet skulle handla om lokalhistoria. Ni vet säkert alla att seminarier är viktiga sammanhang för oss forskare. Ibland kallas forskarseminariet för humanvetenskapernas laboratorium, och med det avses att det är på seminariet som tolkningar presenteras, prövas och förkastas, det är där kunskaper växer fram. Ofta ställer seminariedeltagarna centrala frågor, problem och begrepp i fokus, för någon kan till exempel komma på att ett visst begrepp är otydligt använt, eller i behov av precisering. Vid just det här seminariet var lokalhistoria ämnet för dagen, och samtalet bidrog till att problematisera hur vi ska förstå lokalhistoria och lokalhistoriker idag.

    Ett av de intressantaste inspelen under seminariet kom från en duktig och hedervärd historiker som nämnde att han har forskat på lokalt historiskt material – men han förklarade samtidigt att ”jag är inte lokalhistoriker”.

    Nu kan man uppfatta detta påpekande på olika sätt. Kanske menade historikern i fråga att han i första hand arbetar med annat än lokalt material, eller att de vetenskapliga frågor som han ville försöka besvara inte primärt har med lokalsamhället att göra. Det är fullt rimligt. Men oavsett vad skälet var så tycker jag det är intressant att en forskare på något sätt markerar avstånd till lokalhistoria. Det har nämligen framkommit tidigare att akademiska historiker är motvilliga att säga att de forskar om lokalhistoria och inte heller vill kalla sig själva för lokalhistoriker. Den norske historikern Ingar Kaldal (2007), som skrivit mycket om lokala förhållanden, har uttryckt sig på ungefär samma sätt, alltså förklarat att han inte kallar sig lokalhistoriker. Så något slags spänning föreligger kring lokalhistoria som fenomen och lokalhistoriker som begrepp.

    Jag har ju nyligen blivit professor med inriktning mot lokalhistoria och tänkte därför i den här föreläsningen försöka reda ut 1) vad lokalhistoria är eller kan vara, 2) vad det är som gör lokalhistoria potentiellt laddat, åtminstone i Sverige, men också 3) vad som från mitt perspektiv gör lokalhistoria relevant, angeläget och meningsfullt.

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  • Mugica Garcia, Tania Tamara
    et al.
    Linköpings universitet, Institutionen för beteendevetenskap och lärande.
    Manla Mohamad, Sadiqa
    Linköpings universitet, Institutionen för beteendevetenskap och lärande.
    Modersmålslärare i klassrummet: En intervjustudie om uppfattningar hos modersmålslärare om ledarskåp i klassrummet2023Självständigt arbete på grundnivå (yrkesexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Bakgrund: Modersmålslärare är en del i skolans ansträngningar att underlättaanpassningsprocessen för eleverna som kommer nya till Sverige. Modersmålslärares undervisningkan påverka deras identitet och språkutvecklingen som person. Modersmålslärare kan hjälpaeleverna att lära sig språket som är födda i Sverige. Föräldrar har rätt att prata ett annat språkhemma med sina barn och detta språk tar skolan ansvar för att utveckla medmodersmålsundervisning.

    Syfte: Den här studie handlar om vilka synsätt om ledarskapet som modersmålslärare har iförhållande till riktlinjer och generella direktiv i läroplanen (2022b). Undersökningen utgår utifråntre frågeställningar som är hur uppfattar modersmålslärare att de påverkar elevernas lärande genomsitt språk, sin egen kultur och identitet i undervisningen? Vilka strategier uppfattarmodersmålslärare att de använder för att hantera undervisningen i klassrummet? Hur beskrivermodersmålslärare att de anpassar undervisningen till elevernas olika behov?

    Metod: Vi är inspirerade av fenomenografisk metod, och genom semistrukturerade intervjuerundersökte vi hur modersmålslärare uppfattar ledarskapet i klassrummet. Datainsamlingengenomfördes på nio modersmålslärare från olika skolor i olika kommuner utspridda i Sverige. Vihar analyserat med vägledning utifrån en fenomenografisk analysmodell.

    Resultaten: Ett språk är inte bara ett språk utan det är förankrat med kultur och identitet.Modersmålsläraren är den bryggan mellan kulturen i ursprungslandet för eleverna eller derasföräldrar och den svenska kulturen, språket och identiteten.Vi har identifierat 7 kategorier som påverkar modersmålsundervisning. Studien visar attmodersmålslärare följer läroplanen(2022b), har medveten undervisningsstruktur och har kunskapom skolans värdegrund och dess uppdrag som Skolverket anger i Läroplan för grundskolan,förskoleklassen och fritidshemmet, Lgr 22.

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  • Da Luz Moreira, André
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Mekanisk värmeteori och strömningslära.
    Comparison between CFD and experimental results of the sloshing rising wave in a microgravity environment2019Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The motion of liquids and their free surfaces inside a reservoir is called sloshing.Understanding and predicting their dynamics is relevant to many fields of engineering, from nuclear reactors to orbiting satellites.This requires the knowledge of the liquid position and topology inside a container, which affect the mass distribution and resulting forces acting on the container's walls.When force balances are no longer dominated by gravity, fluid motion becomes greatly influenced by parameters such as surface tension and liquid-solid contact angles.In such microgravity conditions, a comprehensive prediction of the fluid dynamics is not yet available.

    This master's thesis work analyses the results from the experiments performed during the 66th European Space Agency parabolic flight campaign (PFC).The Sloshing PARabolic fliGht Experiment (SPARGE), conducted by researchers from the von Karman Institute (VKI), aimed at investigating the sloshing dynamics via Particle Image Velocimetry (PIV) and Level Detection and Recording (LeDaR). Since these techniques have very different requirements in their acquisition parameters, they were implemented using two cameras. Acceleration data was also recorded, for use as boundary conditions in a Computational Fluid Dynamics (CFD) model.

    This scope of this project was twofold. The first objective was to improve the current LeDaR processing techniques and to define the mapping algorithm to link the videos in the two cameras. The second objective was to simulate the sloshing experiment in microgravity using CFD and to compare the results with experimental data. The proposed approach to LeDaR consisted of a combination of gray scale recontrasting, filtering in the wavelet domain and gradient based detection. This new formulation proved to be more robust against noise and reflection and hence allowed to overcome the limitation of the previous formulation. The CFD simulations consisted of Volume of Fluid (VOF) modelling in OpenFoam, introducing the acceleration from the microgravity experiment as forcing condition and using the experimental level and velocity data as initial conditions. Two simulations with different liquid-wall contact angles were performed to study the influence of the wetting phenomena in the sloshing dynamics. The comparison with the experimental data was carried in terms of interface displacement, velocity fields and forces.

    A good agreement between the experiments and the CFD simulations was achieved, both in the frequency content of the interface displacement and velocity field, in the initial phase of the sloshing. However, major differences appeared in the microgravity phase, although a qualitative comparison remained reasonable. A possible source of discrepancy was found in the initial condition of the velocity field, for which no information on the out-of-plane velocity component and interface location was available from the experiments. Finally, the simulations show a strong sensitivity in the contact angle when comparing the long-term dynamics of the interface topology but appears to have a much weaker influence than expected on the forces and moments exerted on the container walls.

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  • Disputation: 2024-12-20 09:15 Planck, LinköpingBeställ onlineKöp publikationen >>
    Alijan Farzad Lahiji, Faezeh
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Tunnfilmsfysik. Linköpings universitet, Tekniska fakulteten.
    Growth and epitaxy of oxide thin films from conventional to van der Waals epitaxy2024Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    ** The abstract is shortened due to advanced notations. See the PDF for the full abstract **

    In this thesis, the aim is to understand mechanisms behind epitaxial growth, control the crystallinity and properties of grown films, and differentiate between two types of epitaxy: conventional epitaxy, driven by strong chemical bonds between the film and substrate, and van der Waals epitaxy (vdWE), characterized by weaker van der Waals forces, enabling stress-free growth without strict lattice matching. I investigated the epitaxial growth of transition metal oxides and nitrides (NiO, CrN, MoOx (x = 2, 3)) thin films synthesized by reactive magnetron sputtering on various substrates, including silicon, sapphire (c-plane and r-plane) and mica.

    Delarbeten
    1. Growth and optical properties of NiO thin films deposited by pulsed dc reactive magnetron sputtering
    Öppna denna publikation i ny flik eller fönster >>Growth and optical properties of NiO thin films deposited by pulsed dc reactive magnetron sputtering
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    2023 (Engelska)Ingår i: Journal of Vacuum Science & Technology. A. Vacuum, Surfaces, and Films, ISSN 0734-2101, E-ISSN 1520-8559, Vol. 41, nr 6, artikel-id 063402Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    NiO thin films with varied oxygen contents are grown on Si(100) and c-Al2O3 at a substrate temperature of 300 degrees C using pulsed dc reactive magnetron sputtering. We characterize the structure and optical properties of NiO changes as functions of the oxygen content. NiO with the cubic structure, single phase, and predominant orientation along (111) is found on both substrates. X-ray diffraction and pole figure analysis further show that NiO on the Si(100) substrate exhibits fiber-textured growth, while twin domain epitaxy was achieved on c-Al2O3, with NiO(111) k Al2O3(0001) and NiO[1 (1) over bar0]k Al2O3[10 (1) over bar0] or NiO[(1) over bar 10]k Al2O3[2 (1) over bar(1) over bar0] epitaxial relationship. The oxygen content in NiO films did not have a significant effect on the refractive index, extinction coefficient, and absorption coefficient. This suggests that the optical properties of NiO films remained unaffected by changes in the oxygen content.

    Ort, förlag, år, upplaga, sidor
    A V S AMER INST PHYSICS, 2023
    Nationell ämneskategori
    Oorganisk kemi
    Identifikatorer
    urn:nbn:se:liu:diva-198654 (URN)10.1116/6.0002914 (DOI)001069881900002 ()
    Anmärkning

    Funding Agencies|This work was supported financially by the Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkping University (Faculty Grant SFO-Mat-LiU No. 2009 00971), the Knut and Alice Wallenberg Foundation through the [2009 00971]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoeping University; Knut and Alice Wallenberg Foundation [2009 00971]; Swedish Research Council (VR) [KAW-2020.0196]; Swedish Energy Agency [2021-03826]; VR-RFI [46519-1]; Swedish Foundation for Strategic Research (SSF) [2019-00191]; [RIF14-0053]

    Tillgänglig från: 2023-10-23 Skapad: 2023-10-23 Senast uppdaterad: 2024-11-22
    2. Unusual tilted growth and epitaxial relationship of NaCl B1-structured NiO and CrN on r-plane Al2O3
    Öppna denna publikation i ny flik eller fönster >>Unusual tilted growth and epitaxial relationship of NaCl B1-structured NiO and CrN on r-plane Al2O3
    2024 (Engelska)Ingår i: Journal of Applied Physics, ISSN 0021-8979, E-ISSN 1089-7550, Vol. 135, nr 6, artikel-id 065302Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Epitaxial NiO and CrN thin films were deposited on a single-crystal Al2O3(11¯02) (r-plane sapphire) using magnetron sputtering. The two materials were intentionally deposited into two different deposition chamber designs and under different conditions (temperature, pressure, gases, and energy of sputtered particles). Despite the differences in the deposition condition and material system, both materials had the same feature with uncommon tilted epitaxial growth. Through an in-depth x-ray diffraction analysis of the NaCl (B1)-structured materials on r-plane sapphire, the full twin domain epitaxial relations were determined and can be described as (110)NaCl(B1)∥(44¯03)Al2O3 and [11¯2]NaCl(B1)∥[1¯1¯20]Al2O3⁠. This relationship differs from the previously observed orientation of (100)NaCl(B1)∥(11¯02)Al2O3 and [100]NaCl(B1)∥[101¯0]Al2O3⁠. These results are of general relevance for the growth of the extended NaCl (B1)-structured cubic material family onto a r-plane sapphire substrate where similar epitaxial growth can be expected.

    Ort, förlag, år, upplaga, sidor
    American Institute of Physics Inc., 2024
    Nationell ämneskategori
    Annan materialteknik
    Identifikatorer
    urn:nbn:se:liu:diva-201578 (URN)10.1063/5.0188559 (DOI)2-s2.0-85184995860 (Scopus ID)
    Anmärkning

    Funding Agencies|Wallenberg Academy, (KAW-2020.0196); Linköpings Universitet, LiU, (2009 00971); Knut och Alice Wallenbergs Stiftelse; Vetenskapsrådet, VR, (2021-03826); Energimyndigheten, (46519-1)

    Tillgänglig från: 2024-03-13 Skapad: 2024-03-13 Senast uppdaterad: 2024-11-22
    3. Conventional epitaxy of NiO thin films on muscovite mica and c-Al2O3 substrates
    Öppna denna publikation i ny flik eller fönster >>Conventional epitaxy of NiO thin films on muscovite mica and c-Al2O3 substrates
    2024 (Engelska)Ingår i: Thin Solid Films, ISSN 0040-6090, E-ISSN 1879-2731, Vol. 808, artikel-id 140566Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Fiber-textured and epitaxial NiO thin films were deposited on Si(100), c-Al2O3, and muscovite mica(001) sub-strates using reactive magnetron sputtering at substrate temperatures of 300 °C and 400 °C, to investigate theeffect of film thickness and substrate temperature on epitaxial growth of NiO films. The as-deposited filmsexhibited a face-centered cubic structure with a larger lattice constant, attributed to strain induced during thesputtering process. With an increase in substrate temperature to 400 °C, the d-spacing decreased due to strainrelease, approaching the NiO bulk value for the thickest film. The NiO film grown on Si(100) displayed fibertexture. On c-plane sapphire, NiO thin films exhibited twin domains and three-fold symmetry, consistent withexpected crystallographic orientation relationship for NaCl-structured materials onsapphire: (111)NiO ‖ (0001)Al2O3 and [011]NiO ‖ [1010]Al2O3, [011]NiO ‖[1010]Al2O3. On muscovite mica(001)substrates, the observed epitaxial shows that the mechanism is conventional epitaxy, rather than van der Waalsepitaxy, consistent with the epitaxial growth of the non-layered non-van-der-Waals compound NiO. The epitaxialrelationship was identified as of (111)NiO‖(001)Mica and [011]NiO ‖[010]Mica, [011]NiO ‖[010]Mica.

    Nyckelord
    Nickel oxide, Thin films, Magnetron sputtering, Mica, Epitaxy
    Nationell ämneskategori
    Den kondenserade materiens fysik
    Identifikatorer
    urn:nbn:se:liu:diva-209978 (URN)10.1016/j.tsf.2024.140566 (DOI)
    Anmärkning

    Funding agencies: The Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linköping University (Faculty Grant SFO-Mat-LiU No. 2009 00971), the Knut and Alice Wallenberg foundation through the Wallenberg Academy Fellows program (KAW-2020.0196), the Swedish Research Council (VR) under Project No. 2021-03826, and the Swedish Energy Agency under project 52740-1.

    Tillgänglig från: 2024-11-22 Skapad: 2024-11-22 Senast uppdaterad: 2024-11-22Bibliografiskt granskad
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  • Disputation: 2024-12-20 09:15 (BL32), B-building, LinköpingBeställ onlineKöp publikationen >>
    Choolakkal, Arun Haridas
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Tunnfilmsfysik. Linköpings universitet, Tekniska fakulteten.
    Strategies for Conformal Boron Carbide CVD Enabling Trench Deposition and Nanowraps2024Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Thin films are utilized in various applications, including LEDs, solar cells, and microelectronics. Technological advancements necessitate the development of increasingly thinner materials. Researchers in this field face the challenges of developing advanced materials. One approach to address this is by devising new process strategies that enable the synthesis of new materials. This thesis explores the conformal chemical vapor deposition of boron carbide thin films, highlighting the various strategies developed to achieve conformal thin film depositions on intricate morphologies. These materials find applications in solid-state neutron detectors as a neutron converter layer, in the encapsulation of carbon nanotubes, and as free-standing tubular material grown on carbon nanotubes.

    Triethyl boron (TEB, B(C2H5)3) was used as a single source precursor, with its hydrocarbon ligand serving as the carbon source. By limiting the reaction kinetics, excellent conformality with a B-rich composition of B5.2C was achieved in 10:1 aspect ratio structure at 450 °C. The process was further explored with complex morphologies and various temperature regimes, adopting further strategies for the desired characteristics. The kinetically limited growth regime is a compromise between achieving good film conformality at a lower temperature and obtaining higher density at higher temperature. Competitive co-diffusion as a new strategy with the prospect of improving the step coverage at higher temperatures for better film properties was experimented. Using a heavy inert gas (Xe) as a diffusion additive enabled conformal deposition at 550 °C by enhancing the step coverage from 0.71 to 0.97 in 10:1 aspect ratio feature. This process was further tested to encapsulate random oriented carbon nanotubes (CNT) within a membrane structure, achieving uniform deposition B4C thin films without clogging pore sites and allowing tunable porosity. The compatibility observed for B4C thin film growth on CNT surface was achieved without causing significant stress or structural damage, but with a near-surface epitaxial templating. Building on the approach of diffusion additive, adding Kr to the ALD process for AlN resulted in a superconformal deposition in 18:1 aspect ratio Si microstructures.

    The uniformity of film depositions on CNT membrane began to decline with an increased roughness at deposition temperatures above 700 °C. This was mainly due to the flux limited CVD regime, which typically results in sub-conformal growth on intricate morphologies. Although B4C deposition on CNT at 550 °C exhibited a near-surface epitaxial templating, this was not maintained towards the exterior of the cylindrical composite structure. This challenge is analogous to trying to match two dissimilar geometries, i.e., packing rhombohedral unit cell structures on a radial surface. On the other hand, boron carbide can transform into graphitic phase by adding more C. Graphitic layers will be flexible to wrap-around the cylindrical structure of CNTs by adding extra walls to it. By operating in the thermodynamically limited regime, the process uniquely favored the graphitic phase formation and a tubular growth fashion on CNTs. Tubular graphitic boron carbide (g-BCx) growth on both single-walled and few-walled CNTs are demonstrated. The process appears to be a viable route for synthesizing B-doped graphitic nanomaterials, which hold promises for the next generation electronics applications.

    Delarbeten
    1. Conformal chemical vapor deposition of boron-rich boron carbide thin films from triethylboron
    Öppna denna publikation i ny flik eller fönster >>Conformal chemical vapor deposition of boron-rich boron carbide thin films from triethylboron
    2023 (Engelska)Ingår i: Journal of Vacuum Science & Technology. A. Vacuum, Surfaces, and Films, ISSN 0734-2101, E-ISSN 1520-8559, Vol. 41, nr 1, artikel-id 013401Artikel i tidskrift (Refereegranskat) 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/).

    Ort, förlag, år, upplaga, sidor
    A V S AMER INST PHYSICS, 2023
    Nationell ämneskategori
    Materialkemi
    Identifikatorer
    urn:nbn:se:liu:diva-190923 (URN)10.1116/6.0002203 (DOI)000894732600002 ()
    Anmärkning

    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]

    Tillgänglig från: 2023-01-09 Skapad: 2023-01-09 Senast uppdaterad: 2024-11-22
    2. 3D silicon detectors for neutron imaging applications
    Öppna denna publikation i ny flik eller fönster >>3D silicon detectors for neutron imaging applications
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    2023 (Engelska)Ingår i: Journal of Instrumentation, E-ISSN 1748-0221, Vol. 18, nr 1, artikel-id C01056Artikel i tidskrift (Refereegranskat) 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.

    Ort, förlag, år, upplaga, sidor
    IOP Publishing Ltd, 2023
    Nyckelord
    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
    Nationell ämneskategori
    Acceleratorfysik och instrumentering
    Identifikatorer
    urn:nbn:se:liu:diva-192958 (URN)10.1088/1748-0221/18/01/C01056 (DOI)000948372200014 ()
    Konferens
    23rd International Workshop on Radiation Imaging Detectors, Riva del Garda, ITALY, jun 26-30, 2022
    Anmärkning

    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]

    Tillgänglig från: 2023-04-12 Skapad: 2023-04-12 Senast uppdaterad: 2024-11-22
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  • Carlström, Ann Kristin
    Linköpings universitet, Institutionen för kultur och samhälle, Avdelningen för historia, konstvetenskap och religionsvetenskap. 769610-0440.
    Syskonen från Väla socken: En arkivhistorisk undersökning från 1860- till 1970-tal2024Studentarbete övrigt, 5 poäng / 7,5 hpStudentuppsats (Examensarbete)
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  • DIMITRAKOPOULOU, MARIA
    Linköpings universitet, Institutionen för beteendevetenskap och lärande.
    Perceptions and perspectives of Greek Outdoor Educators for ESD implementation in outdoor teaching2024Självständigt arbete på avancerad nivå (magisterexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The growing interest in sustainability has led to numerous studies on the topic highlighting its challenging nature and the limited understanding among education agents. Similarly, typical educators have been interviewed about implementing outdoor education which is considered a component of sustainability education. However, research is scarce on the perspectives of outdoor educators regarding sustainability particularly in Greece, which is what this study aims to address by informing previous findings. This research utilized interviews to capture the thoughts from 12 Greek outdoor pre-school educators and thematic analysis to organize their responses. Their perceptions of sustainability in teaching, their views on implementing it in outdoor settings, and their opinions on EPOSEA map and its dimensions (Environmental, Pluralism, Organizations, Social, Economic and Agents) as a tool for their practices, were explored in depth. The findings revealed some misconceptions and an urgent need for further training, along with that practical challenges faced by educators in Greece were identified too that can have the potential to inform policy changes and professional development programs contributing to more effective practices. The EPOSEA map was viewed as a tool that enhances holistic and experiential learning in sustainability which means that it presents a promising approach for integrating sustainability into outdoor education, warranting further research and support for successful implementation.

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  • Jirenius, Martin
    Linköpings universitet, Institutionen för datavetenskap, Artificiell intelligens och integrerade datorsystem.
    Generating and Leveraging Abstract Explanations for Common-Sense Tasks2022Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    This report contains an extensive and conclusive study of the automatic generation of abstract natural language explanations for model predictions and the effects when leveraging them for various common-sense tasks. The pre-trained language models GPT-2 and BERT are used to generate explanations and classification results for three datasets on different common-sense reasoning tasks. The results show that models can improve their classification performance significantly by the downstream usage of free-form explanations. However, the models cannot immediately transfer from human-annotated explanations to generated explanations but need fine-tuning on generated explanations to adapt and reach high performance.

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    Generating and Leveraging Abstract Natural Language Explanations for Common-Sense Tasks
  • Berzell, Martin
    Linköpings universitet, Institutionen för kultur och samhälle, Avdelningen för filosofi och tillämpad etik. Linköpings universitet, Filosofiska fakulteten.
    Filosofin isamhället: en skriftserie från avdelningenför Filosofi och Tillämpad Etik2024Samlingsverk (redaktörskap) (Övrigt vetenskapligt)
    Abstract [sv]

    Det här är det första numret av forskningsmiljön för Filosofi och tillämpad etiks skriftserie. Innehållet i det här numret är ett axplock av texter från de aktiva forskarna inom miljön. Inför detta första nummer av vår skriftserie ombads författarna att skriva en text som visar hur den filosofiska forskningen eller den filosofiska kompetensen kommer (eller kan komma) till uttryck i samhället utanför akademin. I dessa texter kan man inte bara se bredden inom vår forskningsmiljö, utan även hur brett filosofiämnet är och kan vara. Det ger en god provkarta på hur olika tilltal och angreppssätt som ryms inom ämnet. Man kan tydligt se hur dessa texter representerar olika delar av den verksamhet som ryms i forskningsmiljön och avdelningen för Filosofi och Tillämpad Etik (FTE) inom Institutionen för Kultur och Samhälle (IKOS) på Linköpings Universitet.

    Den inledande texten av Fredrik Stjernberg resonerar kring vad som gör filosofiska frågor specifika, och pekar på hur det verkar nästan omöjligt att komma ifrån filosofin, oavsett hur många gånger den har dödförklarats genom tiderna. Elin Palms text resonerar kring den expertis som etiker sägs kunna ha, och hur detta kommer till uttryck i olika etiska råd i vårt samhälle. Erik Gustavssons text är ett exempel på hur medicinsketiska överväganden görs, i det här fallet specifikt hur man kan tänka kring begreppet ”bot” i relation till behandlingsmetoder inom hälso- och sjukvård.

    Ett annat anslag återfinns i Martin Berzells text om den antika filosofen Epikuros syn på njutning, som ställs i relation till ett modernt konsumtionssamhälle. Här handlar det om hur en filosofisk hållning kan användas för att må bättre själsligt, som skulle kunna ses som en föregångare till vår tids självhjälpslitteratur. Harald Wiltsche å sin sida har skrivit en text om tankeexperiment inom vetenskaperna, och hur man skulle kunna tänka sig att se science fiction-litteratur som en parallell till hur tankeexperiment används inom t.ex. fysik.

    I de tre avslutande texterna kan vi se hur den praktiska filosofin och den tillämpade etiken ger oss begrepp för att beskriva och redskap att hantera olika fenomen i vårt moderna samhälle. Vuko Andrić skriver om det sk boundary problem i demokratifrågor, vilket behandlar frågan om vem som ska tillåtas att delta i demokratiska beslutsfrågor. András Szigeti skriver i sin text om exploatering, och hur relationen mellan exploatering och strukturella orättvisor ser ut. Sist ut är Lars Lindbloms text om rättvisa och fackförbund, där han tar avstamp i Rawls teori om rättvisa för att visa på fackförbundens roll i att uppnå en rättvisare arbetsmarknad.

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  • Disputation: 2024-12-20 13:15 TEMCAS, Tema-building, LinköpingBeställ onlineKöp publikationen >>
    Gustafsson, Daniel
    Linköpings universitet, Institutionen för tema, Tema Barn. Linköpings universitet, Filosofiska fakulteten.
    Making Camp: An ethnographic study of a summer and weekend camp for disabled children and young adults2024Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [sv]

    Studier som rör funktionshindrade barns och unga vuxnas vardagsliv är ofta inriktade på platser och sociala sammanhang som de delar med icke funktionshindrade medborgare. I fokus för denna etnografiska studie står istället ett separat, kommunalt fritidsläger för funktionshindrade barn och unga vuxna som ingår i personkrets 1 i LSS-lagstiftningen. I studien medverkade 20 barn och unga vuxna lägerdeltagare och 21 lägeranställda. Studiens  empiriska material omfattas av intervjuer, videoinspelningar, fältanteckningar och fotografier och syftar till att utforska funktionshindrade barns och unga vuxnas upplevelser, möjligheter och begränsningar på en plats som är skapad bara för dem. Avhandlingen kretsar kring fyra forskningsfrågor som rör hur lagstiftning, policyer och regler påverkar utformningen av lägret som plats, hur aktiviteter och deltagande organiseras och vad det möjliggör, deltagarnas upplevelse av vad tillträde till en separat lägerverksamhet enkom för funktionshindrade barn och unga vuxna gör för dem, samt vilken roll sociala, geografiska, materiella och temporala gränsdragningar har i görandet av lägret. Analysen utgår från tre teoretiska begrepp - transport, wayfaring och orientation - som bidrar till att fördjupa analyserna av platsen.  Analysen är indelad i två övergripande teman där det första handlar om hur aktiviteter gör plats och det andra om hur gränsdragningar gör plats. Det första temat visar hur organisationen av deltagande och lägeraktiviteter skapar en plats som ständigt utgår från deltagarnas individuella önskemål och samtidigt hur aktiviteterna som anordnas på lägret utformas på ett sätt som uppmuntrar kollektivt samarbete och samvaro. Temat visar även på hur lägret blir en plats där deltagarna kan få utforska olika sociala roller och praktiker, samt bygga relationer i en trygg, generös miljö. Det andra temat visar på hur möjligheten att vara på en separat plats som enkom är till för funktionshindrade deltagare bidrar till upplevelsen av att de faktorer som definierar deltagarna som avvikande på andra platser neutraliseras, men att de också kan bidra till en känsla av ambivalens. Analysen av hur olika gränser gör plats visar också på hur policyer relaterade till ålder och relationen mellan deltagare och lägerledare riskerar att bidra till reproduktionen av social isolering och segregation baserad på funktion utanför lägret. Temat visar även hur intressen formade på lägret kan öppna upp en vilja att vidare utforska dessa utanför lägrets gränser, även om det innebär att lägerdeltagaren måste sluta på lägret.

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  • Disputation: 2024-12-19 13:00 Granitsalen, Building 440, LinköpingBeställ onlineKöp publikationen >>
    Davidson, Lee Ti
    Linköpings universitet, Institutionen för biomedicinska och kliniska vetenskaper, Avdelningen för klinisk kemi och farmakologi. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Närsjukvården i centrala Östergötland, Akutkliniken i Linköping.
    Underneath The Obvious: The markers of disease not yet manifested : Evaluation of cardiovascular risk markers in patients with type 2 diabetes and the role of plasma biomarkers in patients presenting to the emergency department with chest pain and/or shortness of breath2024Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Cardiovascular disease (CVD) is the leading cause of death globally, and diabetes mellitus (DM) is increasingly prevalent worldwide. People with DM are at a higher risk of developing heart-related complications that can lead to serious health issues and death. Chest pain (CP) and shortness of breath (SOB) are common manifestations of cardiopulmonary disorders. These symptoms often prompt people to seek emergency medical care.

    Risk stratification involves assessing a patient's probability of experiencing complications and premature death. Determining the necessary interventions to improve the patients' health outcomes is essential. Healthcare professionals encounter daily challenges in risk stratification. Identifying new and clinically relevant markers for improved risk stratification is crucial.

    This thesis aims to assess whether blood biomarkers could predict the risk of adverse events and prognosis in emergency care patients with CP and/or SOB. Additionally, this work evaluates risk markers for identifying patients with higher risk of CVD and premature death in type 2 diabetes (T2DM) patients.

    Papers I and II assessed the predictive values of copeptin, mid-regional pro-adrenomedullin (MRproADM), and mid-regional pro-atrial natriuretic peptide (MRproANP) as potential markers for risk stratification in emergency departments (ED). These studies were based on the ABBA population, a single-center observational study conducted at the Linköping Hospital ED.

    In Paper I, age, sex, oxygen saturation, heart rate, National Early Warning Score (NEWS) category, and copeptin were found to be associated with admission to a hospital ward from the ED. Copeptin was found to have an added predictive value for admission compared to NEWS alone.

    In Paper II, MRproADM levels >0.75 nmol/L and multimorbidity were significantly associated with readmission and/or death within 90 days. MRproADM improved the predictive value of readmission and/or death within 90 days compared to age, sex, and multimorbidity combined. 

    Papers III, IV, and V were based on CARDIPP, a research program aimed at identifying markers for CVD in T2DM patients. This population-based study involved primary care patients aged 55−65, with a baseline survey conducted between 2005 and 2008. The cohort was monitored for CVD morbidity and mortality from a national registry.

    In Paper III, patients with T2DM and low toe brachial index (TBI) had an increased risk of major adverse cardiovascular events (MACE) independent of arterial stiffness.

    In Paper IV, we found that an increasing copeptin level was significantly associated with MACE. Patients with copeptin levels ≥5.6 pmol/L had an unfavorable risk for MACE, independent of traditional CVD risk factors and left ventricular mass index.

    Paper V found that copeptin was associated with TBI and aortic pulse wave velocity (aPWV), both markers of arterial disorders, independent of traditional CVD risk factors.

    In conclusion, early analysis of copeptin may be helpful for patient risk assessments. MRproADM and multimorbidity may predict the risk of readmission and/or death within 90 days. In patients with T2DM, low TBI, and elevated copeptin levels may serve as important indicators for increased risk of MACE. Copeptin may be a helpful surrogate for identifying individuals at higher risk of arterial disorders.

    Delarbeten
    1. Admission of patients with chest pain and/or breathlessness from the emergency department in relation to risk assessment and copeptin levels - an observational study
    Öppna denna publikation i ny flik eller fönster >>Admission of patients with chest pain and/or breathlessness from the emergency department in relation to risk assessment and copeptin levels - an observational study
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    2022 (Engelska)Ingår i: Upsala Journal of Medical Sciences, ISSN 0300-9734, E-ISSN 2000-1967, Vol. 127, nr 1, artikel-id e8941Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Background: One of the most critical decisions that emergency department (ED) physicians make is the discharge versus admission of patients. We aimed to study the association of the decision in the ED to admit patients with chest pain and/or breathlessness to a ward with risk assessment using the Rapid Emergency Triage and Treatment System (RETTS), the National Early Warning Score (NEWS), and plasma levels of the biomarkers copeptin, midregional proadrenomedulin (MR-proADM), and midregional proatrial natriuretic peptide (MR-proANP). Methods: Patients presenting at the ED with chest pain and/or breathlessness with less than one week onset were enrolled. Patients were triaged according to RETTS. NEWS was calculated from the vital signs retrospectively. Results: Three hundred and thirty-four patients (167 males), mean age 63.8 +/- 16.8 years, were included. Of which, 210 (62.8%) patients complained of chest pain, 65 (19.5%) of breathlessness, and 59 (17.7%) of both. Of these, 176 (52.7%) patients were admitted to a ward, and 158 (47.3%) patients were discharged from the ED. In binary logistic models, age, gender, vital signs (O-2 saturation and heart rate), NEWS class, and copeptin were associated with admission to a ward from the ED. In receiver-operating-characteristics (ROC) analysis, copeptin had an incremental predictive value compared to NEWS alone (P = 0.002). Conclusions: Emergency physicians decisions to admit patients with chest pain and/or breathlessness from the ED to a ward are related to age, O-2 saturation, heart rate, NEWS category, and copeptin. As an independent predictive marker for admission, early analysis of copeptin might be beneficial when improving patient pathways at the ED.

    Ort, förlag, år, upplaga, sidor
    UPSALA MED SOC, 2022
    Nyckelord
    Emergency department; chest pain; breathlessness; copeptin; MR-proADM; MR-proANP
    Nationell ämneskategori
    Reumatologi och inflammation
    Identifikatorer
    urn:nbn:se:liu:diva-191199 (URN)10.48101/ujms.v127.8941 (DOI)000905435100001 ()36590754 (PubMedID)
    Anmärkning

    Funding Agencies|Region Ostergotland [RO-285131, RO351681, RO-340001, RO-430481, RO-533731, RO-534451, RO599931, RO-623391, RO-936926]

    Tillgänglig från: 2023-01-24 Skapad: 2023-01-24 Senast uppdaterad: 2024-11-19
    2. Association of physiological stress markers at the emergency department to readmission and death within 90 days: a prospective observational study
    Öppna denna publikation i ny flik eller fönster >>Association of physiological stress markers at the emergency department to readmission and death within 90 days: a prospective observational study
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    2023 (Engelska)Ingår i: Upsala Journal of Medical Sciences, ISSN 0300-9734, E-ISSN 2000-1967, Vol. 128, nr 1, artikel-id e9300Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Background: Predicting the risk of readmission or death in patients at the emergency department (ED) is essential in identifying patients who would benefit the most from interventions. We aimed to explore the prognostic value of mid-regional proadrenomedullin (MR-proADM), mid-regional pro-atrial natriuretic peptide (MR-proANP), copeptin, and high-sensitivity troponin T (hs-TnT) to identify patients with a higher risk of readmission and death among patients presenting with chest pain (CP) and/or shortness of breath (SOB) in the ED.

    Methods: This single-center prospective observational study included non-critically ill adult patients with a chief complaint of CP and/or SOB who visited the ED at Linköping University Hospital. Baseline data and blood samples were collected, and patients were followed up for 90 days after inclusion. The primary outcome was a composite of readmission and/or death from non-traumatic causes within 90 days of inclusion. Binary logistic regression was used and receiver operating characteristics (ROC) curves were constructed to determine the prognostic performance for predicting readmission and/or death within 90 days.

    Results: A total of 313 patients were included and 64 (20.4%) met the primary endpoint. MR-proADM > 0.75 pmol/L (odds ratio [OR]: 2.361 [95% confidence interval [CI]: 1.031 – 5.407], P = 0.042) and multimorbidity (OR: 2.647 [95% CI: 1.282 – 5.469], P = 0.009) were significantly associated with readmission and/or death within 90 days. MR-proADM increased predictive value in the ROC analysis to age, sex, and multimorbidity (P = 0.006).

    Conclusions: In non-critically ill patients with CP and/or SOB in the ED, MR-proADM and multimorbidity may be helpful for the prediction of the risk of readmission and/or death within 90 days.

    Ort, förlag, år, upplaga, sidor
    Uppsala Medical Society, 2023
    Nyckelord
    Emergency department; chest pain; shortness of breath; copeptin; MR-proADM; MR-proANP; readmission; multimorbidity
    Nationell ämneskategori
    Kardiologi
    Identifikatorer
    urn:nbn:se:liu:diva-193613 (URN)10.48101/ujms.v128.9300 (DOI)000990716800001 ()37223634 (PubMedID)
    Anmärkning

    Funding: Region Ostergotland [RO-610991, RO-351681, RO-340001, RO-430481, RO-533731, RO-534451, RO-599931, RO-421461, RO-966396]

    Tillgänglig från: 2023-05-08 Skapad: 2023-05-08 Senast uppdaterad: 2024-11-19Bibliografiskt granskad
    3. Toe brachial index predicts major acute cardiovascular events in patients with type 2 diabetes independently of arterial stiffness
    Öppna denna publikation i ny flik eller fönster >>Toe brachial index predicts major acute cardiovascular events in patients with type 2 diabetes independently of arterial stiffness
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    2020 (Engelska)Ingår i: Diabetes Research and Clinical Practice, ISSN 0168-8227, E-ISSN 1872-8227, Vol. 161, artikel-id 108040Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Objective: Our aim was to analyze the predictive value of toe brachial index (TBI) as a risk marker for future major adverse cardiovascular events (MACE) and all-cause mortality in patients with type 2 diabetes (T2D). Methods: TBI was measured in 741 patients with T2D in 2005-2008. Conventional risk factors for vascular disease as well as non-invasive measurements such as pulse-wave velocity (PWV) and intima-media thickness (IMT) of the carotid arteries were estimated. MACE was defined as cardiovascular death or hospitalization for non fatal myocardial infarction or non fatal stroke. Patients were followed for incidence of MACE using the national Swedish Cause of Death Registry and the Inpatient Register. Results: During the follow-up for a period of 9 years MACE occurred in 97 patients and 85 patients died. TBI tertile, 1 versus 3, was significantly related to MACE (HR 2.67, 95%CI 1.60-4.50; p < 0.001) and to all-cause mortality (HR 1.98, 95%CI 1.16-3.83; p = 0.01). TBI tertile 1 as compared to TBI tertile 3 predicted MACE, but not all-cause mortality, independently of age, sex, diabetes duration and treatment, antihypertensive treatment, previous cardiovascular diseases, office systolic blood pressure, HbA1c, LDL cholesterol, estimated glomerular filtration rate, body mass index, current smoking PWV, IMT and carotid plaque presence (HR 3.39, 95%CI 1.53-7.51; p = 0.003 and HR 1.81, 95%CI 0.87-3.76; p = 0.1, respectively). Conclusions: Low TBI predicts an increased risk for MACE independently of arterial stiffness in patients with type 2 diabetes. Trial registration: Clinical Trials.gov number NCT 01049737. Registered January 14, 2010. (C) 2020 Elsevier B.V. All rights reserved.

    Ort, förlag, år, upplaga, sidor
    ELSEVIER IRELAND LTD, 2020
    Nyckelord
    Type 2 diabetes; Toe pressure; Toe brachial index; Cardiovascular events
    Nationell ämneskategori
    Kardiologi
    Identifikatorer
    urn:nbn:se:liu:diva-165093 (URN)10.1016/j.diabres.2020.108040 (DOI)000520852000033 ()32006647 (PubMedID)
    Tillgänglig från: 2020-04-15 Skapad: 2020-04-15 Senast uppdaterad: 2024-11-19
    4. Plasma copeptin and markers of arterial disorder in patients with type 2 diabetes, a cross-sectional study
    Öppna denna publikation i ny flik eller fönster >>Plasma copeptin and markers of arterial disorder in patients with type 2 diabetes, a cross-sectional study
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    2024 (Engelska)Ingår i: Cardiovascular Diabetology, E-ISSN 1475-2840, Vol. 23, nr 1, artikel-id 200Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Objectives There is currently limited understanding of the relationship between copeptin, the midregional portion of proadrenomedullin (MRproADM) and the midregional fragment of the N-terminal of proatrial natriuretic peptide (MRproANP), and arterial disorders. Toe brachial index (TBI) and aortic pulse wave velocity (aPWV) are established parameters for detecting arterial disorders. This study evaluated whether copeptin, MRproADM, and MRproANP were associated with TBI and aPWV in patients with type 2 diabetes with no history of cardiovascular disease (CVD).

    Methods In the CARDIPP study, a cross-sectional analysis of 519 patients with type 2 diabetes aged 55–65 years with no history of CVD at baseline, had complete data on copeptin, MRproADM, MRproANP, TBI, and aPWV was performed. Linear regression analysis was used to investigate the associations between conventional CVD risk factors, copeptin, MRproADM, MRproANP, TBI, and aPWV.

    Results Copeptin was associated with TBI (β–0.0020, CI–0.0035– (–0.0005), p = 0.010) and aPWV (β 0.023, CI 0.002–0.044, p = 0.035). These associations were independent of age, sex, diabetes duration, mean 24-hour ambulatory systolic blood pressure, glycated hemoglobin A1c, total cholesterol, estimated glomerular filtration rate, body mass index, and active smoking.

    Conclusions Plasma copeptin may be a helpful surrogate for identifying individuals at higher risk for arterial disorders.

    Ort, förlag, år, upplaga, sidor
    Springer, 2024
    Nyckelord
    Type 2 diabetes, Copeptin, MRproADM, MRproANP, Toe brachial index, Pulse wave velocity, Cardiovascular disease
    Nationell ämneskategori
    Endokrinologi och diabetes Kardiologi
    Identifikatorer
    urn:nbn:se:liu:diva-204549 (URN)10.1186/s12933-024-02291-2 (DOI)001249211800001 ()38867292 (PubMedID)
    Forskningsfinansiär
    Linköpings universitet
    Anmärkning

    Funding Agencies|Region Ostergotland [RO-966396]; King Gustaf V and Queen Victoria Freemason Foundation grants; Medical Research Council of Southeast Sweden supported CARDIPP; Linkoping University

    Tillgänglig från: 2024-06-13 Skapad: 2024-06-13 Senast uppdaterad: 2024-11-19Bibliografiskt granskad
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  • Askmar, Elinor
    et al.
    Studiefrämjandet.
    Korsar, Jonathan
    Färnebo folkhögskola.
    Envall, Fredrik
    Linköpings universitet, Institutionen för tema, Tema Miljöförändring. Linköpings universitet, Filosofiska fakulteten. Linköpings universitet, Institutionen för tema, Tema teknik och social förändring.
    Hållbar energi tillsammans: Ett studiematerial om medborgardriven omställning och energigemenskaper2024Övrigt (Övrig (populärvetenskap, debatt, mm))
    Abstract [sv]

    Detta är ett studiematerial för alla som vill göra något ihop med andra kring energi. Materialet tar upp hur vi kan bygga ett smartare, mer demokratiskt och miljövänligt energisystem genom att medborgare, kommuner, kooperativ och andra lokala företag samverkar. Det handlar om hur vi kan starta energigemenskaper för att producera, dela och spara på energi tillsammans. Energigemenskaper är ett sätt att jobba med energi och lokal utveckling. Att starta en studiecirkel kan vara början på många spännande initiativ. Detta studiematerial hjälper dig och några till att utforska olika möjligheter och med kunskap om möjligheterna göra något praktiskt. Kanske finns det redan ett initiativ du vill gå med i? I annat fall ger det här materialet rikligt med kunskap om initiativ som du och några andra kan ta tillsammans för en hållbar, smart och demokratisk energiomställning! 

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  • Disputation: 2024-12-11 08:00 Planck, F-building, LinköpingBeställ onlineKöp publikationen >>
    Wen, Qianyun
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Industriell miljöteknik. Linköpings universitet, Tekniska fakulteten.
    Data-driven Decision Support Applications for Energy Transition2024Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The global energy sector is undergoing a profound transformation driven by the urgent need to address climate change, ensure energy security, and meet growing energy demands sustainably. This energy transition involves a comprehensive shift in production, distribution, and consumption patterns across various sectors, moving from fossil fuel-based systems to those centred on renewable and low-carbon energy sources.

    As this transition progresses, decision-makers at all levels face increasingly com-plex choices that require well-informed strategies. Traditional decision-making approaches, while valuable, often struggle to adequately address the multifaceted nature of energy transition challenges. To navigate these challenges effectively, there is a growing need for data-driven decision support technologies that can enhance and complement conventional methods. This shift towards data-driven approaches is facilitated by the increasing availability of vast amounts of energy-related data from smart grids, internet of things devices, and other digital technologies. This wealth of data provides new opportunities for enhanced decision-making support through improved modelling, forecasting, and optimization capabilities.

    This PhD thesis investigates the role of data-driven decision support tools in facilitating the energy transition. While the research focuses on three representative decision situations – selecting heating technologies for buildings, forecasting energy usage and generation, and establishing energy sharing communities – its in-sights are applicable to a broader range of energy transition challenges.

    The aim of this thesis is to investigate how data-driven decision support tools are designed and applied in energy transition contexts, examining the interconnections between tool characteristics, decision contexts, and stakeholder needs. Two primary research questions guide this investigation: Firstly, what are the critical factors influencing the design and functionality of data-driven decision support tools for selected energy transition contexts? Secondly, how can data-driven decision support tools be effectively applied in different energy transition decisions?

    To address these questions, the thesis provides a review of decision support approaches with practical applications, including multi-criteria decision-making, machine learning models, and optimization techniques. It evaluates their effectiveness in various decision-making situations, considering both the quality of output and the usability of the tools. This dual focus acknowledges that for a tool to have a real impact on energy transition, it should not only provide accurate results but also be accessible and practical for users.

    The findings contribute to the field by identifying key factors in tool design, pro-posing guidelines for application, and offering insights into the integration of multiple decision support techniques. By investigating data-driven decision support in representative energy transition situations, the thesis provides a foundation for in-formed decision-making in a wide range of energy transition contexts. The critical role of adapted, transparent, and user-friendly data-driven decision support tools in navigating the complexities of those specific decision problems is underscored.

    Delarbeten
    1. Fuzzy Ensemble of Multi-Criteria Decision Making Methods for Heating Energy Transition in Danish Households
    Öppna denna publikation i ny flik eller fönster >>Fuzzy Ensemble of Multi-Criteria Decision Making Methods for Heating Energy Transition in Danish Households
    2021 (Engelska)Ingår i: Mathematics, E-ISSN 2227-7390, Vol. 9, nr 19, artikel-id 2420Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    More than 110 countries, including 500 cities worldwide, have set the goal of reaching carbon neutrality. Heating contributes to most of the residential energy consumption and carbon emissions. The green energy transition of fossil-based heating systems is needed to reach the emission goals. However, heating systems vary in energy source, heating technology, equipment location, and these complexities make it challenging for households to compare heating systems and make decisions. Hence, a decision support tool that provides a generalized ranking of individual heating alternatives is proposed for households as decision makers to identify the optimal choice. This paper presents an analysis of 13 heating alternatives and 19 quantitative criteria in technological, environmental, and financial aspects, combines ideal solution-based multi-criteria decision making with 6 weighting methods and 4 normalization methods, and introduces ensemble learning with a fuzzy membership function derived from Cauchy distribution to finalize the ultimate ranking. The robustness of the proposed method is verified by three sensitive analyses from different aspects. Air-to-water heat pump, solar heating and direct district heating are the top three rankings in the final result under Danish national average data. A framework is designed to guide decision makers to apply this ranking guideline with their practical, feasible situations.

    Ort, förlag, år, upplaga, sidor
    MDPI, 2021
    Nyckelord
    multi-criteria decision making; individual heating; fuzzy ensemble; energy transition
    Nationell ämneskategori
    Energisystem
    Identifikatorer
    urn:nbn:se:liu:diva-180526 (URN)10.3390/math9192420 (DOI)000706633600001 ()
    Anmärkning

    Funding Agencies|FlexSUS: Flexibility for Smart Urban Energy Systems [91352]; European Unions Horizon 2020 research and innovation program [775970]; Alliance Joint Research and Publication Seed Funding

    Tillgänglig från: 2021-10-25 Skapad: 2021-10-25 Senast uppdaterad: 2024-11-18
    2. How should you heat your home in the green energy transition? A scenario-based multi-criteria decision-making approach
    Öppna denna publikation i ny flik eller fönster >>How should you heat your home in the green energy transition? A scenario-based multi-criteria decision-making approach
    2023 (Engelska)Ingår i: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 421, artikel-id 138398Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    The choice of heating system is significant for city planners and building owners alike, and many important areas, such as the well-being of residents, climate change impact and resource efficiency, may influence the choice. Understanding how to balance these areas is crucial for effective decision-making that can contribute to sustainable development and the green energy transition. However, these decisions represent complex problems where disparate knowledge areas must be considered simultaneously. When faced with this type of decisionmaking problem, employing different multi-criteria decision-making methods is common. However, such methods only provide a snapshot of which alternative is preferred and because of this, their results may become obsolete due to changes in the performance of alternatives or the value perceptions of the decision-makers. To overcome this challenge and to improve the longevity and reliability of multi-criteria decision-making results, the authors of this study explored a novel approach to producing semi-dynamic results through scenarios, which were used to consider possible future changes to the alternatives performance and the decision-makers value perceptions. The application of scenarios in the multi-criteria decision-making method enabled nuanced information to be produced on how the performance of different heating alternatives may change under different plausible futures. This approach was demonstrated by applying it to the case of residential heating in Denmark, where results showed that while final rankings varied across both scenarios and ranking methods, solar heating was the preferred alternative, while the oil boiler alternative performed the worst. Overall, this study highlights the importance of considering likely future changes to both the performance of alternatives and the value perceptions of decision-makers when making decisions with long lifetimes and suggests an approach for doing this.

    Ort, förlag, år, upplaga, sidor
    ELSEVIER SCI LTD, 2023
    Nyckelord
    Bayesian best-worst method (BWM); Technique for order preference by similarity to; an ideal solution (TOPSIS); Heating; Multi-criteria decision-making; Rank reversal; Scenario
    Nationell ämneskategori
    Annan naturresursteknik
    Identifikatorer
    urn:nbn:se:liu:diva-198363 (URN)10.1016/j.jclepro.2023.138398 (DOI)001070823200001 ()
    Anmärkning

    Funding Agencies|FlexSUS: Flexibility for Smart Urban Energy Systems [91352]; European Union [775970]

    Tillgänglig från: 2023-10-09 Skapad: 2023-10-09 Senast uppdaterad: 2024-11-18
    3. Smart coordinated multi-energy intra-scheduling inter-sharing and cost-saving redistribution for multiple microgrids
    Öppna denna publikation i ny flik eller fönster >>Smart coordinated multi-energy intra-scheduling inter-sharing and cost-saving redistribution for multiple microgrids
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    2023 (Engelska)Ingår i: Sustainable cities and society, ISSN 2210-6707, Vol. 97, artikel-id 104754Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Sustainable and clean multi-energy systems have been hybrid coordinated in microgrid (MG) to fulfill regional multi-energy users economically, but shortages and surpluses still exist. The growth of win-win energy sharing between MGs attracts attention to smart information center (SIC) concept in MGs community, which facilitates sustainable solutions across three key objectives: lower carbon emission, sufficient utilization, and long-term cooperation. This paper designs a two-stage decision framework for day-ahead operations of SIC, where the first stage minimizes the total cost (i.e. operational cost and carbon emission cost) by the proposed multi-energy intra-scheduling and inter-sharing model (MIIM) and the second stage implements the smart cost-saving redistribution model (SCRM) to stimulate MGs in long-term joining of energy sharing. The extended alternating direction multipliers method algorithm (E-ADMM) is developed to protect the privacy of MGs data while approximating the optimal solution of MIIM. The case study proves that a) demand response and energy sharing in MIIM result in cost savings of 2.01% for carbon emissions and 7.25% for total operations; b) renewable energy has been fully utilized and the total multi-energy loss has been avoided nearly 92.22% in MIIM; c) the asymmetric Nash bargaining approach fits the SCRM with incentive cooperation, whereby those who contribute more gain a higher share; d) the optimal gap of E-ADMM is less than 0.2% by iterated insensitive decision result from each MG, which computes in polynomial time when the scale of MG increases; e) the two-stage framework performs better with more heterogeneity of MGs. Furthermore, we provide valuable insights for guidance and models with worldwide generalization potential.

    Ort, förlag, år, upplaga, sidor
    ELSEVIER, 2023
    Nyckelord
    Multi -energy scheduling; Multiple microgrids; Energy sharing; Smart information center; ADMM algorithm; Asymmetric Nash bargaining; Sustainable energy system
    Nationell ämneskategori
    Energisystem
    Identifikatorer
    urn:nbn:se:liu:diva-196695 (URN)10.1016/j.scs.2023.104754 (DOI)001039511700001 ()
    Anmärkning

    Funding Agencies|National Natural Science Foundation of China [72192823, 71821002]; project FlexSUS: Flexibility for Smart Urban Energy Systems [91352]; European Union [775970]

    Tillgänglig från: 2023-08-18 Skapad: 2023-08-18 Senast uppdaterad: 2024-11-18
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  • Munari, Alessandra
    Linköpings universitet, Institutionen för fysik, kemi och biologi.
    The importance of wetlands for early spring bat activity in southern Sweden2024Självständigt arbete på avancerad nivå (magisterexamen), 10,5 poäng / 16 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Insectivorous bats are important providers of ecosystem services such as insect abundance control. Moreover, their high position in trophic chains makes them good bioindicators for habitat quality and insect abundance. Many species of insectivorous bats thrive in tree-surrounded water bodies. Therefore, the decline in quantity and quality of such environments is the main threat to these species. In their life cycle, the most sensitive period is spring awakening from hibernation, when they need to feed. The present study examines the relevance of water presence and pond size for supporting bat activity in early spring in Tinnerö Nature Reserve in Southern Sweden. In March and April 2024, I monitored bat activity in 21 locations, of which 16 were near wetlands of different sizes and 5 lacked any wetlands in the surrounding. Bat activity was significantly higher in areas close to wetlands than in areas far from wetlands and tended to be higher in larger wetlands in the first weeks of the study. My study emphasises the importance of wetlands to bats, regardless of their size.

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  • Lundin Münch, Hugo
    Linköpings universitet, Institutionen för systemteknik, Elektroniska Kretsar och System.
    Design, Implementation, and Evaluation of a Flexible High-Impedance Analog Frontend2024Självständigt arbete på avancerad nivå (masterexamen), 28 hpStudentuppsats (Examensarbete)
    Abstract [en]

    This thesis report presents the design, implementation, and evaluation of a flexible high impedance analog frontend. The proposed design is simulated and implemented in a printed circuit board assembly (PCBA). It is evaluated and compared with target specifications that were chosen to prove the viability of the design. To make the results comparable to those of similar frontends, the proposed design includes features such as a high-impedance attenuator, a variable DC-offset, and bandwidth limiting filters. These flexible features are controlled by a microcontroller included in the design. For the evaluation, some target specifications are achieved for some configurations. For example, the target bandwidth of 500 MHz is achieved and exceeded when using the frontend with a 10x passive probe. However, to properly assess the proposed design, performance would have to be evaluated for all possible configurations on all output ports.

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  • Löf, Kristin
    Gränsdragningar i det kommunala beslutsfattandet: Hur ledande förtroendevalda och ledande tjänstepersoner drar gränsen mellan beslut i kommunallagens mening och ren verkställighet.2024Rapport (Övrigt vetenskapligt)
    Abstract [sv]

    Sverige rankas som ett av världens mest decentraliserade länder. Utöver en förhållandevis stark självstyrelse ansvarar kommunerna för en rad tunga välfärdsområden som exempelvis skola, äldreomsorg och socialtjänst (Ladner et al. 2021). Sålunda fattas det dagligen en mängd beslut i kommunerna som har en direkt eller indirekt påverkan på dess invånare. Besluten fattas av de förtroendevalda, delegeras av de förtroendevalda till de anställda eller hanteras som så kallad ”ren verkställighet”.

    Till dags dato har tidigare forskning, om än i begränsad omfattning, bland annat fokuserat på besluten som är förbehållna de förtroendevalda och förtroendevaldas möjligheter att delegera sådana beslut till anställda (t.ex. Höök 2000; Höök 2020; SKL 2012). Däremot har mycket lite forskningsfokus riktats mot det som i kommunsektorn kallas ”ren verkställighet”, det vill säga de åtgärder som inte omfattas av det formella beslutsfattandet. Föreliggande uppsats handlar om hur gränsdragningen görs mellan vad som betraktas som ”beslut” respektive ”ren verkställighet”. Frågan är underutforskad. Detta är olyckligt sett till frågans vikt.

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  • Törneholm, Anders (Redaktör)
    Linköpings universitet, Universitetsförvaltningen.
    LiU Magasin2024Övrigt (Övrig (populärvetenskap, debatt, mm))
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  • Ekeroth, Anna
    et al.
    Linköpings universitet, Institutionen för hälsa, medicin och vård.
    Allequist, Felicia
    Linköpings universitet, Institutionen för hälsa, medicin och vård.
    Fysioterapeuters erfarenheter av fysioterapeutisk rehabilitering vid samlagssmärta efter vaginal förlossning: En kvalitativ intervjustudie2024Självständigt arbete på grundnivå (kandidatexamen), 180 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Syfte: Syftet med denna kvalitativa studie var att beskriva fysioterapeuters tankar och erfarenheter av att möta och behandla kvinnor med samlagssmärta efter vaginal förlossning.

    Metod: Sju fysioterapeuter från olika delar av Sverige intervjuades. Fysioterapeuterna hade klinisk erfarenhet av att rehabilitera patienter med samlagssmärta efter vaginal förlossning. Intervjuerna genomfördes på Zoom och tolkades med kvalitativ innehållsanalys med induktiv ansats.

     

    Resultat: Resultatet visar att ett helhetsinriktat och patientcentrerat förhållningssätt, kombinerat med patientens engagemang och egen insats, är avgörande för att effektivt behandla samlagssmärta hos kvinnor efter en vaginal förlossning. Problemen som dessa kvinnor har är ofta komplexa och fysioterapeuterna upplevde därför ett värde av att arbeta interprofessionellt. Fysioterapeuterna ansåg även att kommunikationen med dessa patienter var en viktig del för att patienterna skulle få adekvat behandling.

     

    Konklusion: Ett helhetsinriktat och patientcentrerat förhållningssätt kombinerat med patientens engagemang vad enligt fysioterapeuterna avgörande för att effektiv behandla samlagssmärta hos kvinnor efter en vaginal förlossning. Resultatet av denna kandidatuppsats kan användas som vägledning för fysioterapeuter som arbetar kliniskt med denna patientgrupp.

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  • Disputation: 2024-12-18 13:00 Hasselquistsalen, LinköpingBeställ onlineKöp publikationen >>
    Jönsson, Mika
    Linköpings universitet, Institutionen för hälsa, medicin och vård, Avdelningen för prevention, rehabilitering och nära vård. Linköpings universitet, Medicinska fakulteten.
    The Inflammatory Profile in Chronic Peripheral Neuropathic Pain: Explorative studies investigating Potential Biomarker Candidates2024Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Neuropathic pain (NeuP), a complex and debilitating pain condition caused by a lesion or disease affecting the somatosensory system, is associated with symptoms of pathologically amplified responses to noxious and innocuous stimuli. Although several etiological conditions have been implicated in the instigation of NeuP, little is known about the underlying molecular mechanisms involved, which is reflected in the current lack of diagnostic tests and effective treatment options. This thesis investigates the inflammatory profile at different levels of integrated immunological systems across different body fluids with implications for chronic peripheral NeuP.

    In paper I, the inflammatory pattern of cytokines and chemokines between NeuP patients and healthy controls was concurrently investigated in three separate biofluids: saliva, plasma, and cerebrospinal fluid (CSF). Multivariate data analysis revealed that most of the significant cytokines and chemokines for group discrimination were found in the less invasive biofluids of saliva and plasma. The resultant pattern of upregulated pro-inflammatory mediators in the patient group was coherent with systemic low-grade inflammation. This finding was further corroborated in paper II, where the plasma profile of lipoprotein fractions indicated metabolic changes in the patient group consistent with ongoing inflammation. Particularly, a fraction of apolipoprotein A-1 containing high-density lipoprotein (HDL) was significantly reduced in the patient group, indicative of aberrant HDL functioning which usually carries immunoprotective properties. Consequently, the immuno-lipoprotein interphase was further investigated by a system-wide targeted approach in paper III. The lipoprotein proteome and oxidation pattern were consistent with previous findings indicative of systemic low-grade inflammation. Plasma samples isolated for HDL and low-density lipoprotein (LDL) supported results from paper II, i.e., structural changes in HDL and LDL were seen in the patient group associated with reduced regular function. These changes were accompanied by both increased levels of different isoforms of acute-phase protein serum amyloid A (SAA) and increased HDL oxidation. In addition, 13 oxylipins derived from 18-carbon precursor fatty acids were significantly reduced in the patient group compared to the controls. Seven of the significantly reduced oxylipins also showed significant activating effects on the Kv7.2/7.3 potassium ion channel, which could affect nociceptor excitability and pain signalling. In paper IV, the specificity of identified inflammatory patterns and biomolecules were investigated by comparing a second pain group diagnosed with chronic widespread pain (CWP). Corroborating the findings in paper I, most of the significant cytokines and chemokines, discriminating NeuP patients against healthy controls and CWP, were detected in plasma. Like the findings in paper III, oxylipins derived from 18-carbon fatty acids followed a similar downregulated trend in both pain groups compared to healthy controls, which was particularly distinct for NeuP.

    In conclusion, this thesis found the presence of systemic low-grade inflammation and deviant immunoprotective functions of lipoproteins in patients with chronic peripheral NeuP, which were highly interconnected with the detected pro-inflammatory cytokine profile. In addition, novel oxylipin interactions at Kv7.2/7.3 signalling revealed a potentially endogenous mechanism of excitability control of nociceptors, where the specific oxylipins were downregulated in NeuP. Hence, this thesis highlights lipoproteins and their associated bioactive metabolites as interesting targets for further scrutiny.

    Delarbeten
    1. The inflammatory profile of cerebrospinal fluid, plasma, and saliva from patients with severe neuropathic pain and healthy controls - a pilot study
    Öppna denna publikation i ny flik eller fönster >>The inflammatory profile of cerebrospinal fluid, plasma, and saliva from patients with severe neuropathic pain and healthy controls - a pilot study
    2021 (Engelska)Ingår i: BMC Neuroscience, E-ISSN 1471-2202, Vol. 22, nr 1, artikel-id 6Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Background: Neuropathic pain (NeuP) is a complex, debilitating condition of the somatosensory system, where dysregulation between pro- and anti-inflammatory cytokines and chemokines are believed to play a pivotal role. As of date, there is no ubiquitously accepted diagnostic test for NeuP and current therapeutic interventions are lacking in efficacy. The aim of this study was to investigate the ability of three biofluids - saliva, plasma, and cerebrospinal fluid (CSF), to discriminate an inflammatory profile at a central, systemic, and peripheral level in NeuP patients compared to healthy controls. Methods: The concentrations of 71 cytokines, chemokines and growth factors in saliva, plasma, and CSF samples from 13 patients with peripheral NeuP and 13 healthy controls were analyzed using a multiplex-immunoassay based on an electrochemiluminescent detection method. The NeuP patients were recruited from a clinical trial of intrathecal bolus injection of ziconotide (ClinicalTrials.gov identifier NCT01373983). Multivariate data analysis (principal component analysis and orthogonal partial least square regression) was used to identify proteins significant for group discrimination and protein correlation to pain intensity. Proteins with variable influence of projection (VIP) value higher than 1 (combined with the jack-knifed confidence intervals in the coefficients plot not including zero) were considered significant. Results: We found 17 cytokines/chemokines that were significantly up- or down-regulated in NeuP patients compared to healthy controls. Of these 17 proteins, 8 were from saliva, 7 from plasma, and 2 from CSF samples. The correlation analysis showed that the most important proteins that correlated to pain intensity were found in plasma (VIP > 1). Conclusions: Investigation of the inflammatory profile of NeuP showed that most of the significant proteins for group separation were found in the less invasive biofluids of saliva and plasma. Within the NeuP patient group it was also seen that proteins in plasma had the highest correlation to pain intensity. These preliminary results indicate a potential for further biomarker research in the more easily accessible biofluids of saliva and plasma for chronic peripheral neuropathic pain where a combination of YKL-40 and MIP-1 alpha in saliva might be of special interest for future studies that also include other non-neuropathic pain states.

    Ort, förlag, år, upplaga, sidor
    BMC, 2021
    Nyckelord
    Biomarker; Cytokines; Inflammation; Neuroinflammation; Biofluids
    Nationell ämneskategori
    Neurologi
    Identifikatorer
    urn:nbn:se:liu:diva-173876 (URN)10.1186/s12868-021-00608-5 (DOI)000616135500001 ()33522900 (PubMedID)
    Anmärkning

    Funding Agencies|Linkoping University; Swedish Research CouncilSwedish Research CouncilEuropean Commission; County Council of Ostergotland (Research-ALF); NEURO Sweden

    Tillgänglig från: 2021-03-09 Skapad: 2021-03-09 Senast uppdaterad: 2024-11-14
    2. Differences in plasma lipoprotein profiles between patients with chronic peripheral neuropathic pain and healthy controls: an exploratory pilot study
    Öppna denna publikation i ny flik eller fönster >>Differences in plasma lipoprotein profiles between patients with chronic peripheral neuropathic pain and healthy controls: an exploratory pilot study
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    2022 (Engelska)Ingår i: Pain Reports, E-ISSN 2471-2531, Vol. 7, nr 5, artikel-id e1036Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Introduction: Little is still known about the underlying mechanisms that drive and maintain neuropathic pain (NeuP). Recently, lipids have been implicated as endogenous proalgesic ligands affecting onset and maintenance of pain; however, in the case of NeuP, the relationship is largely unexplored. Objectives: The aim of this study was to investigate the lipoprotein profile in patients with chronic peripheral NeuP compared with healthy controls. Methods: The concentrations of 112 lipoprotein fractions in plasma from patients with NeuP (n = 16) and healthy controls (n = 13) were analyzed using proton nuclear magnetic resonance spectroscopy. A multiplex immunoassay based on an electrochemiluminescent detection method was used to measure the concentration of 71 cytokines in plasma from patients with NeuP (n = 10) and healthy controls (n = 11). Multivariate data analysis was used to identify patterns of protein intercorrelations and proteins significant for group discrimination. Results: We found 23 lipoproteins that were significantly upregulated in patients with NeuP compared with healthy controls. When the influence of cytokines was included in a regression model, 30 proteins (8 cytokines and 22 lipoprotein fractions) were significantly upregulated or downregulated in patients with NeuP. Both conditions presented lipoprotein profiles consistent with inflammation. Body mass index did not affect lipoprotein profiles in either group. No relationship between age and lipoprotein pattern was found in NeuP, but a significant relationship was found in healthy controls. Conclusion: Patients with NeuP presented a lipoprotein profile consistent with systemic low-grade inflammation, like that seen in autoimmune, cardiometabolic, and neuroprogressive diseases. These preliminary results emphasize the importance of chronic low-grade inflammation in NeuP.

    Ort, förlag, år, upplaga, sidor
    Lippincott, Williams & Wilkins, 2022
    Nyckelord
    Biomarker; Inflammation; VLDL; LDL; IDL; HDL; Cytokines
    Nationell ämneskategori
    Reumatologi och inflammation
    Identifikatorer
    urn:nbn:se:liu:diva-189108 (URN)10.1097/PR9.0000000000001036 (DOI)000857692800001 ()36203648 (PubMedID)
    Anmärkning

    Funding Agencies|Swedish Research Council; ALF Research Grants; Region Ostergotland; NEURO Sweden

    Tillgänglig från: 2022-10-11 Skapad: 2022-10-11 Senast uppdaterad: 2024-11-14
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  • Sjökvist, Moa
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Statsvetenskap. Linköpings universitet, Filosofiska fakulteten.
    Exploring EU Media Policy in a Changing Landscape: Comparing the development of the Audiovisual Media Service Directive and the European Media Freedom Act by applying the Advocacy Coalition Framework2024Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The study explores the development of media policy in the EU by comparing the development of the Audiovisual Media Service Directive (AVMSD) and the European Media Freedom Act (EMFA). A policy analysis was conducted applying the Advocacy Coalition Framework (ACF) to examine how interest organizations and EU-institutions shape policy outcomes. The ACF highlights policy changes occur due to developments within the policy subsystem, external subsystem events, policy-oriented learning, and negotiated agreements. By examining the propositions of ACF and the scope of both legislations, a significant policy shift in media policy the past decade can be identified. Hence, the study aims to answer why a media freedom policy was proposed today and not a decade ago by comparing two media polices composed in different time-periods. 

    Policy subsystems, external subsystem events, policy-oriented learning and negotiated agreements played pivotal roles in shaping both policies. Technological advancements and the emergence of AV-services necessitated regulatory responses in both cases. The developments were posing threats to EU competition leading to the Commission viewing the current situation as untenable. Additionally, the EMFA responded to socio-political challenges like democratic backsliding and journalist rights violations. The conclusion indicates the EMFA was developed due to the mobilization of advocacy coalitions combined with increasing empirical evidence of declining media freedom. As a result, the study concludes that the ACF is of high relevance for comparative policy research, offering valuable insights into why media freedom regulation has become a priority in contemporary Europe.

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  • Disputation: 2024-12-13 09:15 Nobel (BL32), B-building, LinköpingBeställ onlineKöp publikationen >>
    Dorri, Samira
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Tunnfilmsfysik. Linköpings universitet, Tekniska fakulteten.
    The route towards perfection of multifunctional artificial CrB2/TiB2 superlattices: stoichiometry, structure, and layer definition2024Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    Konstgjorda supergitter med sina exceptionella egenskaper har varit populära i ett brett spektrum av användningsområden såsom elektroniska, magnetiska, optiska och hårda beläggningar. En annan potentiell tillämpning för enkristallsupergitter är högeffektiv interferensneutronoptik, tack vare att gränssnitten mellan lagren kan vara så tunna som endast ±½ atomlager. Studier av supergitter har även varit avgörande för att förstå härdnings-mekanismerna i övergångsmetall-nitrider och -karbider medan sådana studier på övergångsmetalldiborider saknas, trots omfattande studier av monolitiska tunna filmer.

    Denna avhandling beskriver en logisk serie av studier som löser en rad grundläggande problem som möjliggjort epitaxiell tillväxt av högkvalitativa CrB2/TiB2-diboridsupergitter på substrat av enkristallin safir och kiselkarbid genom magnetronsputtring. Detta innebar implementering av flera olika strategier; sputtring från diboridkällor, samsputtring från separata metall- och diboridkällor, sputtring från titanmonoborid- och kromdiboridkällor, kontroll av tillväxt-kinetiken på atomlagernivå genom argonjon-assisterad epitaxi samt val av substrat med liten gittermissanpassning. Effekter på supergittrens kristallstruktur och gränssnittskvalitet studeras med avseende på substrattemperatur, borstökiometri (B/metall-förhållande), modulerings-period Λ = DCrB2 + DTiB2, skikttjockleksförhållande Γ = DTiB2/(DCrB2 + DTiB2), jonassistans-energi, användning av gränssnittsskyddande buffertlager, samt val av safir- eller kiselkarbid-substrat. Röntgendiffraktion, röntgenreflektivitet, neutronreflektivitet, jonstråleanalys, transmissionselektronmikroskopi, elektronenergiförlustspektroskopi, elektron-diffraktion och nanoindentation används för karakterisering.

    För alla experimentella förhållanden har det visat sig att den högsta strukturella kvaliteten hos supergittren erhålls för skikttjockleksförhållandet Γ ≈ 0,3. Vid användning av safirsubstrat och sputtring från Cr- och Ti-diboridkällor med ett optimalt sputtergastryck pAr = 4 mTorr och en substrattemperatur på 600 °C, har vi funnit att supergitter med moduleringsperiod Λ = 6 nm och Γ i intervallet 0,2-0,4 uppvisar den högsta strukturella kvaliteten. Emellertid resulterar överstökiometriska TiBy-skikt (y > 2) i segregering av bor som i sin tur leder till tillväxt av supergitter i smala kolumnära epitaxiella domäner med strukturellt förvrängda borrika gränser.

    Genom att samsputtra från en Ti- och en TiB2-källa, och välja det rätta effektförhållandet till sputterkällorna, kan y skräddarsys i intervallet 0,9 till 3,3 i TiBy-lagren. Samsputtrade TiB2,3 enkellager uppvisar 10x större epitaxiella domäner än icke-samsamsputtrade filmer, samt ger högkvalitativa, nära stökiometriska, CrB1,7/TiB2,3 supergitter vid en högre tillväxttemperatur på 750 °C. De individuella CrB1.7-skikten växer på ett tvådimensionellt sätt vilket leder till släta ytor och atomärt abrupta gränssnitt när TiB2,3 odlas ovanpå. Däremot uppvisar TiB2,3-skikt ojämna gränssnitt då CrB1,7 odlas ovanpå vilket tyder på en kinetiskt begränsad tredimensionell tillväxtmod av TiB2,3. Skillnaden i tillväxtsätt mellan CrB1,7 och TiB2,3 tillskrivs en 1100 K skillnad i smälttemperaturer. Genom att introducera användningen av en sputterkälla av titanmonoborid uppnås kontinuerliga och nästan stökiometriska TiB1,8-epilager av hög kristallkvalitet, vilket lättar på alla processbegränsningar tack vare behovet av balanserade flöden från Ti- och TiB2-källorna. Samtidigt implementeras jonassisterad epitaxiell tillväxt, genom lågenergetiska Ar-joner som extraheras från sputterplasmat, för att stimulera rörligheten hos adatomerna, särskilt för TiB1,8 som har den högsta smälttemperaturen. De bästa supergittren erhålls genom användningen av en TiB-källa kombinerat med Ar-jonenergier på 31 eV och 60 eV för CrB1,9 respektive TiB1,8, vid en tillväxttemperatur på 1173 K. CrB1,9/TiB1,8 supergitter med enkristallkvalitet och supergitterskiktsdefinition som överstiger något av de tidigare erhållna supergittren. Ytterligare förbättring av gränssnittems abrupthet erhålls genom att påbörja tillväxten av varje enskilt skikt med ett atomlager utan jonassistans, som bildar skyddande buffertskikt på de nyss bildade lagergränsytorna, vilka hindrar joninducerad intermixning av av atomer mellan skikten under den följande jonassisterade tillväxten av återstoden av varje lager.

    Fördelarna med att använda ett gitteranpassat substrat påvisas genom att använda kiselkarbid (4H-SiC) som endast uppvisar -1,29 % gittermissanpassning mot supergittren jämfört med -26 % för safir (Al2O3) som använts i de tidigare experimenten i detta arbete. SiC möjliggör odling av högkvalitativa enkristallsupergitter även med tjockleksförhållanden Γ = 0,5 och Γ = 0,7. Detta tillskrivs supergittertillväxt med töjda lager och mindre relaxering av gitterspänningar under kylningen efter tillväxt.

    Delarbeten
    1. Effects of stoichiometry and individual layer thickness ratio on the quality of epitaxial CrBx/TiBy superlattice thin films
    Öppna denna publikation i ny flik eller fönster >>Effects of stoichiometry and individual layer thickness ratio on the quality of epitaxial CrBx/TiBy superlattice thin films
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    2023 (Engelska)Ingår i: Materials & design, ISSN 0264-1275, E-ISSN 1873-4197, Vol. 228, artikel-id 111842Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Studies of single crystal artificial superlattices (SLs) of transition-metal (TM) diborides, which is instru- mental to understand hardening mechanisms at nanoscale, is lacking. Here, CrBx/TiBy (0001) diboride SLs [x,y E 1.7-3.3] are grown epitaxially on Al2O3(0001) substrates by direct-current magnetron sputter epitaxy. Growth conditions for obtaining well-defined SLs with good interface quality are found at 4 mTorr Ar pressure and 600 degrees C. 1 -mu m-thick SL films deposited with modulation periods A between 1 and 10 nm, and A=6 nm SLs with TiBy-to-A layer thickness ratios F ranging from 0.2 to 0.8 are studied. SLs with A=6 nm and F in the range of 0.2-0.4, with a near stoichiometric B/TM ratio, exhibit the high- est structural quality. The effects of F and stoichiometries (B/TM ratio) on the distribution of B in the SL structures are discussed. By increasing the relative thickness of TiBy, the crystalline quality of SLs starts to deteriorate due to B segregation in over-stoichiometric TiBy, resulting in narrow epitaxial SL columnar growth with structurally-distorted B-rich boundaries. Moreover, increasing the relative thickness of under-stoichiometric CrBx enhances the SL quality and hinders formation of B-rich boundaries. The SLs are found to exhibit hardness values in the range of 29-34 GPa.(c) 2023 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).

    Ort, förlag, år, upplaga, sidor
    ELSEVIER SCI LTD, 2023
    Nyckelord
    Diborides; Superlattices; Thin films; Thickness ratio; Modulation period; Stoichiometry
    Nationell ämneskategori
    Materialkemi
    Identifikatorer
    urn:nbn:se:liu:diva-194825 (URN)10.1016/j.matdes.2023.111842 (DOI)000998208000001 ()
    Anmärkning

    Funding Agencies|Swedish National Graduate School in Neutron Scattering (SwedNess); Swedish Foundation for Strategic Research (SSF) [GSn15 -0008]; Swedish Government Strategic Research Area in Materials Science on Advanced Functional Materials (AFM) at Linkoeping University (Faculty Grant SFO Mat LiU) [2009 00971]; Swedish Research Council VR [2019-00191, 2021-00357]; Knut and Alice Wallenberg Foundation [KAW 2015.0043]

    Tillgänglig från: 2023-06-14 Skapad: 2023-06-14 Senast uppdaterad: 2024-11-14
    2. Enhanced quality of single crystal CrBx/TiBy diboride superlattices by controlling boron stoichiometry during sputter deposition
    Öppna denna publikation i ny flik eller fönster >>Enhanced quality of single crystal CrBx/TiBy diboride superlattices by controlling boron stoichiometry during sputter deposition
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    2024 (Engelska)Ingår i: Applied Surface Science, ISSN 0169-4332, E-ISSN 1873-5584, artikel-id 159606Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Single-crystal CrB2/TiB2 diboride superlattices with well-defined layers are promising candidates for neutron optics. However, excess B in sputter-deposited TiBy using a single TiB2 target deteriorates the structural quality of CrBx/TiBy (0001) superlattices. We study the influence of co-sputtering of TiB2 + Ti on the stoichiometry and crystalline quality of 300-nm-thick TiBy single layers and CrBx/TiBy (0001) superlattices on Al2O3(0001) substrates grown by DC magnetron sputter epitaxy at growth-temperatures TS ranging from 600 to 900 °C. By controlling the relative applied powers to the TiB2 and Ti magnetrons, y could be reduced from 3.3 to 0.9. TiB2.3 grown at 750 °C exhibited epitaxial domains about 10x larger than non-co-sputtered films. Close-to-stoichiometry CrB1.7/TiB2.3 superlattices with modulation periods Λ = 6 nm grown at 750 °C showed the highest single crystal quality and best layer definition. TiB2.3 layers display rough top interfaces indicating kinetically limited growth while CrB1.7 forms flat and abrupt top interfaces indicating epitaxial growth with high adatom mobility.

    Ort, förlag, år, upplaga, sidor
    Elsevier, 2024
    Nyckelord
    Superlattice, Diboride, Thin film, Co-sputtering, Nanostructure
    Nationell ämneskategori
    Den kondenserade materiens fysik
    Identifikatorer
    urn:nbn:se:liu:diva-200730 (URN)10.1016/j.apsusc.2024.159606 (DOI)001183388000001 ()
    Anmärkning

    Funding: Swedish National Graduate School in Neutron Scattering (SwedNess), Swedish Foundation for Strategic Research (SSF) GSn15 - 0008, Swedish Government Strategic Research Area in Materials Science on Advanced Functional Materials (AFM) at Linköping University (Faculty Grant SFO Mat LiU No. 2009 00971), Center in Nanoscience and technology at LiTH CeNano, Hans Werthén Foundation (IVA), Society of Vacuum Coaters Foundation (SVCF), Swedish Research Council (VR) Grant numbers 2019-00191 (for accelerator-based ion-technological center in tandem accelerator laboratory in Uppsala University), VR and SSF for access to ARTEMI, the Swedish National Infrastructure in Advanced Electron Microscopy (2021-00171 and RIF21-0026), Knut and Alice Wallenberg Foundation for the support of the electron microscopy laboratory at Linköping University (KAW 2015.0043), VR 2021-00159 for the Swedish neutron reflectometer SuperADAM at ILL 10.5291/ILL-DATA.CRG-2964, and Plansee GmbH for providing diboride targets.

    Tillgänglig från: 2024-02-06 Skapad: 2024-02-06 Senast uppdaterad: 2024-11-14Bibliografiskt granskad
    3. TiB1.8 single layers and epitaxial TiB2-based superlattices by magnetron sputtering using a TiB (Ti:B = 1:1) target
    Öppna denna publikation i ny flik eller fönster >>TiB1.8 single layers and epitaxial TiB2-based superlattices by magnetron sputtering using a TiB (Ti:B = 1:1) target
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    2024 (Engelska)Ingår i: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 494, artikel-id 131534Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Sputter-deposited titanium diborides are promising candidates for protective coatings in harsh and extreme conditions. However, growing these layers from TiB2 diboride targets by DC magnetron sputtering usually leads to over-stoichiometric layers with low crystal qualities. Moreover, superlattices with TiB2 as one of the constituents have been becoming popular, owing to their superior mechanical properties compared to single layer constituents in addition to their use in other applications such as neutron optics. Here, we propose the use of a TiB (Ti:B = 1:1) sputtering target in an on-axis deposition geometry and demonstrate the growth of epitaxial sub-stoichiometric TiB1.8 thin films. Furthermore, we present the growth of CrB1.7/TiB1.8 superlattices, from TiB (Ti:B = 1:1) and stoichiometric CrB2 targets, with abrupt interfaces as promising materials system for neutron interference mirrors. The high crystal quality structure with well-defined interfaces is the common feature of superlattices which, regardless of application, should be addressed during the growth process.

    Utilizing TiB target, all films crystallize in the hexagonal AlB2 structure. The sub-stoichiometry of the TiB1.8 films was accompanied by the presence of planar defects embedded in the films. CrB1.7/TiB1.8 superlattices exhibited a homogeneous boron distribution within the layers with no sign of B-rich tissue phases through the layers. This study demonstrates the feasibility for TiB as sputter target material, that offers a solution for deposition of TiB2-based superlattices without the need to adjust the deposition parameters. Such adjustments would otherwise be unavoidable for tuning the TiB2 composition and could affect the growth of the other constituent materials.

    Ort, förlag, år, upplaga, sidor
    Elsevier, 2024
    Nyckelord
    Titanium diboride, Superlattices, Stoichiometry, Magnetron sputter epitaxy
    Nationell ämneskategori
    Den kondenserade materiens fysik
    Identifikatorer
    urn:nbn:se:liu:diva-209664 (URN)10.1016/j.surfcoat.2024.131534 (DOI)001353994700001 ()
    Anmärkning

    Funding: The authors acknowledge financial support from Swedish National Graduate School in Neutron Scattering (SwedNess), Swedish Foundation for Strategic Research (SSF) GSn15 - 0008, Swedish Government Strategic Research Area in Materials Science on Advanced Functional Materials (AFM) at Linköping University (Faculty Grant SFO Mat LiU No. 2009 00971), S.D. acknowledges student grants from Center in Nanoscience and technology at LiTH CeNano 2021 and 2022, scholarships from Society of Vacuum Coaters Foundation (SVCF) 2023, and Hans Werthén Foundation (IVA) 2023. Swedish Research Council (VR) Grant numbers 2019-00191 (for accelerator-based ion-technological center in tandem accelerator laboratory in Uppsala University), VR and SSF for access to ARTEMI, the Swedish National Infrastructure in Advanced Electron Microscopy (2021-00171 and RIF21-0026), Knut and Alice Wallenberg Foundation for the support of the electron microscopy laboratory at Linköping University (KAW 2015.0043).

    Tillgänglig från: 2024-11-14 Skapad: 2024-11-14 Senast uppdaterad: 2024-11-28Bibliografiskt granskad
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  • Dorri, Samira
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Tunnfilmsfysik. Linköpings universitet, Tekniska fakulteten.
    Palisaitis, Justinas
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Tunnfilmsfysik. Linköpings universitet, Tekniska fakulteten.
    Kolozsvári, Szilárd
    Plansee Composite Materials GmbH, Lechbruck am See, Germany.
    Polcik, Peter
    Plansee Composite Materials GmbH, Lechbruck am See, Germany.
    Persson, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Tunnfilmsfysik. Linköpings universitet, Tekniska fakulteten.
    Ghafoor, Naureen
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Tunnfilmsfysik. Linköpings universitet, Tekniska fakulteten.
    Eriksson, Fredrik
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Tunnfilmsfysik. Linköpings universitet, Tekniska fakulteten.
    Birch, Jens
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Tunnfilmsfysik. Linköpings universitet, Tekniska fakulteten.
    TiB1.8 single layers and epitaxial TiB2-based superlattices by magnetron sputtering using a TiB (Ti:B = 1:1) target2024Ingår i: Surface & Coatings Technology, ISSN 0257-8972, E-ISSN 1879-3347, Vol. 494, artikel-id 131534Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Sputter-deposited titanium diborides are promising candidates for protective coatings in harsh and extreme conditions. However, growing these layers from TiB2 diboride targets by DC magnetron sputtering usually leads to over-stoichiometric layers with low crystal qualities. Moreover, superlattices with TiB2 as one of the constituents have been becoming popular, owing to their superior mechanical properties compared to single layer constituents in addition to their use in other applications such as neutron optics. Here, we propose the use of a TiB (Ti:B = 1:1) sputtering target in an on-axis deposition geometry and demonstrate the growth of epitaxial sub-stoichiometric TiB1.8 thin films. Furthermore, we present the growth of CrB1.7/TiB1.8 superlattices, from TiB (Ti:B = 1:1) and stoichiometric CrB2 targets, with abrupt interfaces as promising materials system for neutron interference mirrors. The high crystal quality structure with well-defined interfaces is the common feature of superlattices which, regardless of application, should be addressed during the growth process.

    Utilizing TiB target, all films crystallize in the hexagonal AlB2 structure. The sub-stoichiometry of the TiB1.8 films was accompanied by the presence of planar defects embedded in the films. CrB1.7/TiB1.8 superlattices exhibited a homogeneous boron distribution within the layers with no sign of B-rich tissue phases through the layers. This study demonstrates the feasibility for TiB as sputter target material, that offers a solution for deposition of TiB2-based superlattices without the need to adjust the deposition parameters. Such adjustments would otherwise be unavoidable for tuning the TiB2 composition and could affect the growth of the other constituent materials.

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  • Olofsson, Rasmus
    et al.
    Linköpings universitet, Institutionen för systemteknik, Reglerteknik.
    Roos, Adam
    Linköpings universitet, Institutionen för systemteknik, Reglerteknik.
    Decentralized Collaborative EKF-SLAM for UAV Fleets Utilizing Monocular Cameras and UWB Sensors2024Självständigt arbete på avancerad nivå (masterexamen), 28 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The deployment of Unmanned Aerial Vehicles (UAVs) has increased considerably in recent years, extending to a wide range of real-world applications. For a single UAV to self-localize and map the environment, a Simultaneous Localization and Mapping (SLAM) algorithm can be utilized. However, in scenarios where the capabilities of a single UAV are limited, multiple UAVs can collaborate to solve the SLAM problem, this is known as Collaborative-SLAM (C-SLAM). This thesis presents a C-SLAM algorithm specifically designed for use with multiple UAVs, capable of processing data and exchanging various types of information with neighbouring UAVs.

    The C-SLAM algorithm is implemented and evaluated in a simulation environment where each UAV is equipped with multiple monocular cameras, an Inertial Measurement Unit (IMU), and an Ultra-wideband (UWB) node. The environment that is being mapped is represented by stationary reference points, known as landmarks, which the camera can detect and measure bearing to. An Extended Kalman Filter (EKF) is used to integrate measurements from the various sensors, enabling the UAVs to localize themselves and create a map of the environment. The goal for each UAV is to collaboratively produce the best possible estimates of both the map and their own positions, surpassing the accuracy of a non-collaborative single-SLAM configuration.

    The developed C-SLAM system is capable of operating in both centralized and decentralized configurations. The focus is on the decentralized configuration, as it is more practical in real-world applications. The decentralized configuration is compared to the centralized performance, which is considered the reference solution, with the goal of approaching its performance as closely as possible. In the decentralized configurations, different questions are investigated.

    The first question addresses how different fusion methods affect performance. Among these are Covariance Intersection (CI) and Naïve Fusion (NF), where CI gave the best results in terms of accuracy and consistency. The second question explores which types of information are most relevant to exchange between the UAVs. Various combinations of measurements and estimates are studied to identify which data exchange strategy yields the best results. Here, sharing more information generally led to improved performance, but the effectiveness depends on the specific information shared. Using the correct combination of measurements and estimates is essential to enhance performance. Sharing camera measurements is considered the most likely way to significantly enhance performance. Lastly, the third question assess the performances of the decentralized configurations under limited communication bandwidth. The system is tested with varying rates of information sharing. This investigation aims to understand how different sharing frequencies impact the accuracy and consistency of the system. The results demonstrate that the system can effectively adapt to varying levels of data exchange without a significant loss of performance.

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  • Disputation: 2024-12-13 09:00 Hugo Theorell, LinköpingBeställ onlineKöp publikationen >>
    Yusuf, Ibtisam
    Linköpings universitet, Institutionen för hälsa, medicin och vård, Avdelningen för diagnostik och specialistmedicin. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Diagnostikcentrum, Medicinsk strålningsfysik.
    Uranium biokinetics and internal dosimetry2024Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    A future shift to more nuclear power requires a rise in uranium mining and uranium processing to meet the demands for nuclear fuel. This can lead to a risk of increased occupational exposure to uranium for nuclear industry workers and a heightened risk of uranium exposure for members of the public. Exposure to uranium involves both chemical and radiological risks. In order to minimize radiological risks and ensure compliance with regulatory dose limits, accurate dose assessments are essential. For internal exposure, biokinetic and dosimetric models developed by the International Commission on Radiological Protection (ICRP) are used to derive dose and intake estimates from bioassay samples.

    These biokinetic models have been developed and updated over the years based on research into physiological processes and characteristics of the intake that influence the biokinetics of inhaled, ingested, and systemically distributed radionuclides. As physicochemical properties such as chemical form and aerosol particle size distribution can greatly influence the distribution, retention, and absorption, it is advised that material-specific input parameters be derived for better dose estimations.

    The aim of this thesis work is to refine uranium biokinetic modeling to improve dose estimates and provide better risk assessments for uranium inhalation and ingestion exposures. Papers I-III pertained to the assessment of exposure to uranium aerosols at a specific nuclear fuel fabrication plant. Paper IV had a more general application and addressed uranium excretion to hair and urine after ingestion exposure.

    The solubility of uranium aerosols encountered in nuclear fuel fabrication in the gastrointestinal and respiratory tracts was evaluated using in vitro models in Papers I and III. Material-specific absorption parameters were derived for inhalation and ingestion exposure for the uranium compounds present at the nuclear fuel fabrication plant. In vivo studies (Papers II and IV) were conducted to obtain model parameters, such as absorption values for inhalation and ingestion. Human hair has long been debated as a possibly robust and practical bioassay for determining doses in cases of uranium intake. The uptake of soluble uranium and its excretion into hair and urine were assessed, testing the hypothesis of significant uranium uptake in hair in Paper IV.

    The main findings in this thesis work include (i) material-specific absorption parameters for uranium inhalation and ingestion exposure that can improve dose and risk assessments of exposed personnel and (ii) the demonstration of minimal uranium uptake in hair, contrary to other reports. This is a finding that can provide aid in the choice of biokinetic model and has a significant impact on the accuracy of dose assessments. Other findings include data on the urinary excretion of uranium, which quantifies intestinal retention and, if included in the current biokinetic model for the gastrointestinal tract, can greatly improve dose estimations.In conclusion, the findings in this thesis work cover vital knowledge gaps in uranium biokinetics and internal dosimetry. The derived model parameters can significantly improve dose estimates of uranium exposure for both inhalation and ingestion exposure. 

    Delarbeten
    1. Particle Size Dependent Dissolution of Uranium Aerosols in Simulated Gastrointestinal Fluids
    Öppna denna publikation i ny flik eller fönster >>Particle Size Dependent Dissolution of Uranium Aerosols in Simulated Gastrointestinal Fluids
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    2023 (Engelska)Ingår i: Health Physics, ISSN 0017-9078, E-ISSN 1538-5159, Vol. 124, nr 4, s. 285-300Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Uranium aerosol exposure can be a health risk factor for workers in the nuclear fuel industry. Good knowledge about aerosol dissolution and absorption characteristics in the gastrointestinal tract is imperative for solid dose assessments and risk management. In this study, an in vitro dissolution model of the GI tract was used to experimentally study solubility of size-fractionated aerosols. The aerosols were collected from four major workshops in a nuclear fuel fabrication plant where uranium compounds such as uranium hexafluoride (UF6), uranium dioxide (UO2), ammonium uranyl carbonate, AUC [UO2CO3 center dot 2(NH4)(2)CO3] and triuranium octoxide (U3O8) are present. The alimentary tract transfer factor, f(A), was estimated for the aerosols sampled in the study. The transfer factor was derived from the dissolution in the small intestine in combination with data on absorption of soluble uranium. Results from the conversion workshop indicated a f(A) in line with what is recommended (0.004) by the ICRP for inhalation exposure to Type M materials. Obtained transfer factors, f(A), for the powder preparation and pelletizing workshops where UO2 and U3O8 are handled are lower for inhalation and much lower for ingestion than those recommended by the ICRP for Type M/S materials f(A) = 0.00029 and 0.00016 vs. 0.0006 and 0.002, respectively. The results for ingestion and inhalation f(A) indicate that ICRPs conservative recommendation of f(A) for inhalation exposure is applicable to both ingestion and inhalation of insoluble material in this study. The dissolution- and subsequent absorption-dependence on particle size showed correlation only for one of the workshops (pelletizing). The absence of correlation at the other workshops may be an effect of multiple chemical compounds with different size distribution and/or the reported presence of agglomerated particles at higher cut points having more impact on the dissolution than particle size. The impact on dose coefficients [committed effective dose (CED) per Bq] of using experimental f(A) vs. using default f(A) recommended by the ICRP for the uranium compounds of interest for inhalation exposure was not significant for any of the workshops. However, a significant impact on CED for ingestion exposure was observed for all workshops when comparing with CED estimated for insoluble material using ICRP default f(A). This indicates that the use of experimentally derived site-specific f(A) can improve dose assessments. It is essential to acquire site-specific estimates of the dissolution and absorption of uranium aerosols as this provides more realistic and accurate dose- and risk-estimates of worker exposure. In this study, the results indicate that ICRPs recommendations for ingestion of insoluble material might overestimate absorption and that the lower f(A) found for inhalation could be more realistic for both inhalation and ingestion of insoluble material.

    Ort, förlag, år, upplaga, sidor
    LIPPINCOTT WILLIAMS & WILKINS, 2023
    Nyckelord
    dose; internal; gastrointestinal tract; nuclear fuel cycle; uranium
    Nationell ämneskategori
    Arbetsmedicin och miljömedicin
    Identifikatorer
    urn:nbn:se:liu:diva-192476 (URN)10.1097/HP.0000000000001668 (DOI)000937057800004 ()36727932 (PubMedID)
    Anmärkning

    Funding Agencies|Swedish Radiation Safety Authority [SSM2016-589-2]; Westinghouse Electric Sweden AB

    Tillgänglig från: 2023-03-20 Skapad: 2023-03-20 Senast uppdaterad: 2024-11-13
    2. Uranium Body Clearance Kinetics-A Long-term Follow-up Study of Retired Nuclear Fuel Workers
    Öppna denna publikation i ny flik eller fönster >>Uranium Body Clearance Kinetics-A Long-term Follow-up Study of Retired Nuclear Fuel Workers
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    2024 (Engelska)Ingår i: Health Physics, ISSN 0017-9078, E-ISSN 1538-5159, Vol. 127, nr 4, s. 520-535Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Nuclear industry workers exposed to uranium aerosols may risk kidney damage and radiation-induced cancer. This warrants the need for well-established dose and risk assessments, which can be greatly improved by using material-specific absorption parameters in the ICRP Human Respiratory Tract Model. The present study focuses on the evaluation of the slow dissolution rate (s(s), d(-1)), a parameter that is difficult to quantify with in vitro dissolution studies, especially for more insoluble uranium compounds. A long-term follow-up of urinary excretion after the cessation of chronic inhalation exposure can provide a better estimate of the slow-rate dissolution. In this study, two workers, previously working for >20 y at a nuclear fuel fabrication plant, provided urine samples regularly for up to 6 y. One individual had worked at the pelletizing workshop with the known presence of uranium dioxide (UO2) and triuranium octoxide (U3O8). The second individual worked at the conversion workshop where multiple compounds, including uranium hexafluoride (UF6), uranium dioxide (UO2), ammonium uranyl carbonate, and AUC [UO2CO3<middle dot>2(NH4)(2)CO3], are present. Data on uranium concentration in urine during working years were also available for both workers. The daily excretion of uranium by urine was characterized by applying non-linear least square regression fitting to the urinary data. Material-specific parameters, such as the activity median aerodynamic diameter (AMAD), the respiratory tract absorption parameters, rapid fraction (f(r),), rapid dissolution rate (s(r), d(-1)), and slow dissolution rate (s(s), d(-1)) and alimentary tract transfer factor (f(A)) acquired from previous work along with default absorption types, were applied to urine data, and the goodness of fit was evaluated. Thereafter intake estimates and dose calculations were performed. For the ex-pelletizing worker, a one-compartment model with a clearance half-time of 662 +/- 100 d (s(s) = 0.0010 d(-1)) best represented the urinary data. For the ex-conversion worker, a two-compartment model with a major [93% of the initial urinary excretion (A(0))] fast compartment with a clearance half-time of 1.3 +/- 0.4 d (s(r) = 0.5 d(-1)) and a minor (7% of A(0)) slow compartment with a half-time of 394 +/- 241 d (s(s) = 0.002 d(-1)) provided the best fit. The results from the data-fitting of urinary data to biokinetic models for the ex-conversion worker demonstrated that in vitro derived experimental parameters (AMAD = 20 mu m, f(r) = 0.32, s(r) = 27 d(-1), s(s) = 0.0008 d(-1), f (A) = 0.005) from our previous work best represented the urinary data. This resulted in an estimated intake rate of 0.66 Bq d(-1). The results from the data-fitting of urinary data to biokinetic models for the ex-pelletizing worker indicated that the experimental parameters (AMAD = 10 mu m and 20 mu m, f(r) = 0.008, s(r) = 12 d(-1), f(A) = 0.00019) from our previous dissolution studies with the slow rate parameter step-wise optimized to urine-data (s(s) = 0.0008 d(-1)) gave the best fit. This resulted in an estimated intake rate of 5 Bq d(-1). Experimental parameters derived from in vitro dissolution studies provided the best fit for the subject retired from work at the conversion workshop, where inhalation exposure to a mix of soluble (e.g., AUC, UF6) and relatively insoluble aerosol (e.g., UO2) can be assumed. For the subject retired from work at the pelletizing workshop, which involved exposure to relatively insoluble aerosols (UO2 and U3O8), a considerably higher s(s) than obtained in dissolution studies provided a better representation of the urinary data and was comparable to reported s(s) values for UO2 and U3O8 in other studies. This implies that in vitro dissolution studies of insoluble material can be uncertain. When evaluating the results from the retrospective fitting of urine data, it is evident that the urine samples acquired after cessation of exposure provide less fluctuation. Long-term follow-up of uranium excretion after cessation of exposure is a good alternative for determining absorption parameters and can be considered the most viable way for determining the slow rate for more insoluble material.

    Ort, förlag, år, upplaga, sidor
    LIPPINCOTT WILLIAMS & WILKINS, 2024
    Nyckelord
    dose, internal; excretion, urinary; nuclear fuel cycle; uranium
    Nationell ämneskategori
    Arbetsmedicin och miljömedicin
    Identifikatorer
    urn:nbn:se:liu:diva-207630 (URN)10.1097/HP.0000000000001861 (DOI)001304594900001 ()39058313 (PubMedID)
    Anmärkning

    Funding Agencies|Swedish Radiation Safety Authority [SSM2016-589-2]

    Tillgänglig från: 2024-09-16 Skapad: 2024-09-16 Senast uppdaterad: 2024-11-13
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  • Disputation: 2024-12-13 13:15 K1, Kåkenhus, NorrköpingBeställ onlineKöp publikationen >>
    Björklund-Flärd, Daniel
    Linköpings universitet, Institutionen för beteendevetenskap och lärande, Avdelningen för lärande, estetik och naturvetenskap. Linköpings universitet, Utbildningsvetenskap.
    Where a Glance is an action: Drilling visual routines in driver training2024Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    Förare förlitar sig i stor utsträckning på seendet för att navigera och samspela med andra trafikanter. Den erfarne förarens förmåga att se skiljer sig dock avsevärt från novisens eftersom den erfarne föraren har utvecklat ett slags seende som är utmärkande för en kompetent bilförare (jfr professional vision, Goodwin, 1994). Denna sammanläggningsavhandling undersöker hur specifika praktiker för att se i trafik lärs ut och in i förarutbildning. Avhandlingen fokuserar särskilt på hur spår av lärande synliggörs i och genom deltagarnas interaktion.

    Studie I undersöker hur spegelrutinen, en standardprocedur för att söka av den omgivande trafikmiljön, lärs ut. Utifrån tidigare observationer (Garfinkel, 1967) visar studien hur instruktioner är svårhanterliga som pedagogiska verktyg och illustrerar den retrospektiva-prospektiva karaktär som präglar människors meningsskapande. Studie II visar hur praktiken att kolla döda vinkeln, ett av de moment som utgör spegelrutinen, först introduceras och senare övas i trafik. Analysen visar hur instruktioner anpassas till såväl den omgivande miljön som till elevens framväxande kompetens. Studie III undersöker deltagarnas arbete med att etablera ett gemensamt seende när man ska bestämma en navigationspunkt för en körmanöver. Den visar hur seende, som ett socialt fenomen, förutsätter deltagares koordinering av olika sensoriska praktiker.

    Tecken på lärande kan urskiljas i deltagarnas orientering mot lärande som ett resultat av samspel över tid, som ömsesidig explicit orientering, och som föränderligt deltagande i en pågående aktivitet. Att lära sig att se som ”en förare” innebär en perceptuell omstrukturering av den omgivande miljön (Nishizaka, 2006). Sensorialitet kan därmed anses utgöra ett centralt inslag i olika lärprocesser. För att lära sig att titta och se trafik behöver körelever därmed ges tillräckliga möjligheter att öva dessa förmågor i en miljö där dessa instruerade praktiker också tillämpas.

    Delarbeten
    1. Drilling the mirror routine: From non‐situated looking to mobile practice in driver training
    Öppna denna publikation i ny flik eller fönster >>Drilling the mirror routine: From non‐situated looking to mobile practice in driver training
    2018 (Engelska)Ingår i: International Journal of Applied Linguistics, ISSN 0802-6106, E-ISSN 1473-4192, Vol. 28, nr 2, s. 226-247Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    This paper uses ethnomethodology and conversation analysis to trace the instructed development of a practical skill (the ‘mirror routine’) in a driving school in Sweden. Focusing the interaction between instructor and student, it applies a micro longitudinal perspective by examining five video excerpts from a total of ≈15 minutes of one driving lesson with a single constellation of student/instructor. Detailed analyses show how, by deploying different instructional resources, instructions are adapted to operate under a range of mobile and infrastructural contingencies, distinguishing between stationary and mobile instructions while considering the reflexive relation between the two. By and large, learning the mirror routine is a complex task in which the participants must deal with issues of instructions, temporality and practical multi-activity at the same time.

    Ort, förlag, år, upplaga, sidor
    Wiley-Blackwell Publishing Inc., 2018
    Nyckelord
    conversation analysis; ethnomethodology; learning; looking; social interaction
    Nationell ämneskategori
    Lärande
    Identifikatorer
    urn:nbn:se:liu:diva-197827 (URN)10.1111/ijal.12201 (DOI)000439789900002 ()2-s2.0-85043358791 (Scopus ID)
    Tillgänglig från: 2023-09-16 Skapad: 2023-09-16 Senast uppdaterad: 2024-11-12Bibliografiskt granskad
    2. Seeing together: The organisation of looking and seeing in navigational driving instructions
    Öppna denna publikation i ny flik eller fönster >>Seeing together: The organisation of looking and seeing in navigational driving instructions
    2024 (Engelska)Ingår i: Language & Communication, ISSN 0271-5309, E-ISSN 1873-3395, Vol. 98, s. 45-59Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    This paper examines the coordination of vision when formulating place in driver training. Specifically, the study examines the visual practices involved when jointly establishing where to change direction. First, it shows how visual availabilities are exploited in establishing the place for the instructed driving action, and second, how verbal and embodied instructions may be adjusted to new visualities as movement in space ongoingly change the visual landscape. In conclusion, place formulations are questions that seek to establish a mutual reference point. By showing how the parties secure joint visual access to a landmark and how instructions are reflexively related to a changing visual environment, the study highlights the role of shared perception for giving and making sense of directions.

    Ort, förlag, år, upplaga, sidor
    PERGAMON-ELSEVIER SCIENCE LTD, 2024
    Nyckelord
    Vision; Perception; Learning; Instruction; Navigation; Landmark
    Nationell ämneskategori
    Jämförande språkvetenskap och allmän lingvistik
    Identifikatorer
    urn:nbn:se:liu:diva-207134 (URN)10.1016/j.langcom.2024.06.003 (DOI)001293400400001 ()
    Anmärkning

    Funding Agencies|Committee for Educational Sciences of the Swedish research Council [721-2012-5367]

    Tillgänglig från: 2024-09-03 Skapad: 2024-09-03 Senast uppdaterad: 2024-11-12
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  • Disputation: 2024-12-11 13:15 Ada Lovelace, B-building, LinköpingBeställ onlineKöp publikationen >>
    Hindlycke, Christoffer
    Linköpings universitet, Institutionen för systemteknik, Informationskodning. Linköpings universitet, Tekniska fakulteten.
    Understanding the Speedup of Quantum Computation2024Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    En kvantdator tillämpar kvantmekanikens axiom för att effektivt köra kvantalgoritmer, vilka utför beräkningar som, enligt rådande hypotes, kräver exponentiella resurser (tid eller minne) på en klassisk dator. Denna avhandling fokuserar på att förbättra vår förståelse, och därmed vår implementation, av kvantalgoritmer och modeller av (en delteori av) de kvantmekaniska grunderna vilka bestämmer hur kvantdatorer fungerar. Våra bidrag består av tre delar.

    Först konstruerar vi en effektiv Einstein-Podolsky-Rosen(EPR)-komplett gömd-variabel-modell av del-teorin av kvantmekanik som ges av stabilisatorformalismen. Att vara EPR-komplett innebär att varje verklig storhet inryms i modellen.

    Därefter skapar vi en rotations-algoritm för en kvantbit användandes den universella Toffoli-grinden. Vår konstruktion har ett logaritmiskt grinddjup, och därmed som mest ett logaritmiskt antal Toffolis, vilket är en kraftig förbättring jämfört med existerande algoritmer. Kretsen medger en effektiv konstruktion, som nyttjar en jämförelse med en konstant vilken fås genom ett trigonometriskt uttryck, och därmed kan grindnätet konstrueras i polynomiell tid. Vi utför tillstånds- och processtomografi på vår algoritm körandes på en simulerad såväl som en riktig kvantdator, och analyserar resultaten, därvidlag erhållandes goda uppskattningar av vår algoritms prestanda under varierande (båda simulerade och verkliga) brusnivåer.

    Slutligen studerar vi Rekursiv Fourier-Sampling (RFS): Kvantalgoritmen som löser RFS är en av de första sådana som verkar ge ett övertag över klassiska algoritmer. Genom att omformulera RFS i termer av den information dess orakel skriver in i kvantbitarnas fas, visar vi att kvantalgoritmen som löser RFS utnyttjar kvantberäkningsresursen känd som fasrekyl, stärkandes liknande argument i relaterade arbeten. Vi visar även att algoritmen inte kan förbättras: Beräkningarna utförda av dess orakel måste göras ogjorda, enär slumpmässig information skrivs in i fasen.

    Delarbeten
    1. Efficient Contextual Ontological Model of n-Qubit Stabilizer Quantum Mechanics
    Öppna denna publikation i ny flik eller fönster >>Efficient Contextual Ontological Model of n-Qubit Stabilizer Quantum Mechanics
    2022 (Engelska)Ingår i: Physical Review Letters, ISSN 0031-9007, E-ISSN 1079-7114, Vol. 12, nr 13, artikel-id 130401Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    The most well-known tool for studying contextuality in quantum computation is the n-qubit Stabilizer state tableau representation. We provide an extension that not only describes the quantum state but is also outcome deterministic. The extension enables a value assignment to exponentially many Pauli observables, yet it remains quadratic in both memory and computational complexity. Furthermore, we show that the mechanisms employed for contextuality and measurement disturbance are wholly separate. The model will be useful for investigating the role of contextuality in n-qubit quantum computation.

    Ort, förlag, år, upplaga, sidor
    American Physical Society, 2022
    Nationell ämneskategori
    Annan fysik
    Identifikatorer
    urn:nbn:se:liu:diva-189798 (URN)10.1103/PhysRevLett.129.130401 (DOI)000865420000009 ()36206422 (PubMedID)
    Anmärkning

    Funding Agencies|Bibsam

    Tillgänglig från: 2022-11-08 Skapad: 2022-11-08 Senast uppdaterad: 2024-11-12
    2. Single-qubit rotation algorithm with logarithmic Toffoli count and gate depth
    Öppna denna publikation i ny flik eller fönster >>Single-qubit rotation algorithm with logarithmic Toffoli count and gate depth
    2024 (Engelska)Ingår i: Physical Review Research, E-ISSN 2643-1564, Vol. 6, nr 4, artikel-id L042027Artikel i tidskrift, Letter (Övrigt vetenskapligt) Published
    Abstract [en]

    Building generic gates from a restricted gate set is a difficult but important problem, especially in the noisy regime where only a limited set of noise-resistant gates are available, e.g., fault-tolerant Clifford gates (generated by Hadamard, phase, and cnot gates) and fault-tolerant Toffoli gates. The Toffoli is also often used as a building block of many algorithms and will need to be constructed if not directly available. This makes Clifford+Toffoli an attractive gate set for building generic gates. In this Letter we give a simple and efficient algorithm for building an approximate single-qubit rotation using only Clifford+Toffoli, which in turn enables any generic single-qubit unitary. An important difference compared to earlier attempts is that the use of the Toffoli allows us to use simple rounding as opposed to a complicated approximation algorithm. The resulting gate array does not rely on repeatedly applying a fixed rotation, but immediately applies a rotation 𝑅𝜃* that is 𝜀-close to the desired rotation 𝑅𝜃, with a success probability strictly greater than 1/2. It can be rerun upon failure, giving an expected number of repetitions strictly less than 2, an expected Toffoli count strictly less than 4⁢⌈log⁡1𝜀⌉, an expected gate depth strictly less than 4⁢⌈log⁡1𝜀⌉+6, and uses 2⁢⌈log⁡1𝜀⌉ ancillas. The small circuit depth of our construction enables low-noise gates on existing quantum computational devices, and allows for arbitrary precision using a very modest number of ancillas.

    Ort, förlag, år, upplaga, sidor
    American Physical Society, 2024
    Nationell ämneskategori
    Signalbehandling
    Identifikatorer
    urn:nbn:se:liu:diva-209231 (URN)10.1103/physrevresearch.6.l042027 (DOI)001345755600003 ()
    Tillgänglig från: 2024-11-07 Skapad: 2024-11-07 Senast uppdaterad: 2024-11-21
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  • Palm, Elin
    et al.
    Linköpings universitet, Institutionen för kultur och samhälle, Avdelningen för filosofi och tillämpad etik. Linköpings universitet, Filosofiska fakulteten.
    Lindblom, Lars
    Linköpings universitet, Institutionen för kultur och samhälle, Avdelningen för filosofi och tillämpad etik. Linköpings universitet, Filosofiska fakulteten.
    Introduction2024Ingår i: Research ethics: ethical review and beyond / [ed] Elin Palm and Lars Lindblom, Linköping: Linköping University Electronic Press, 2024, , s. 57s. 5-8Kapitel i bok, del av antologi (Övrigt vetenskapligt)
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  • Palm, Elin
    et al.
    Linköpings universitet, Institutionen för kultur och samhälle, Avdelningen för filosofi och tillämpad etik. Linköpings universitet, Filosofiska fakulteten.
    Lindblom, LarsLinköpings universitet, Institutionen för kultur och samhälle, Avdelningen för filosofi och tillämpad etik. Linköpings universitet, Filosofiska fakulteten.
    Research ethics: ethical review and beyond2024Samlingsverk (redaktörskap) (Övrigt vetenskapligt)
    Abstract [en]

    Science is a collective endeavor highly dependent on public acceptance and trust. Research findings must be reliable to serve the surrounding society as well as the research community itself. Evidence-based practice and policy recommendations may become ineffective or even dangerous if based on fraudulent research findings. Research persons directly involved in research projects and stakeholders affected by the research outcome should be able to trust in researchers´ integrity and rest assured that their rights and interests are duly respected within academic research. As David B Resnik notes, those who produce knowledge bear responsibility for the effects of the knowledge that they produce (Resnik, 1998:147). However, good research practice is not only about individual responsibility-taking and compliance. It is also a matter of conditions for good research practice within the organizations where academic research is conducted. Being the entities responsible for research, universities and higher education institutions are obligated to foster and maintain scientific integrity (Högskolelagen 1992:1434) and good research practice (Higher education ordinance/Högskoleförordningen (1993:100) chapter 1, 3 a §). They must also ensure that co-workers can get advice and support in questions regarding good research practice and deviations from such conduct (Chapter 1, 16 §).

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  • Hugoh, Felix
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling. Linköpings universitet, Filosofiska fakulteten.
    Wild, Oscar
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling.
    Utdelningspolicy och aktiepris-volatilitet: Bevis från den svenska aktiemarknaden2024Självständigt arbete på avancerad nivå (magisterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Bakgrund: Aktiers prisvolatilitet är en viktig strategisk aspekt för många investerare. Detsamma gäller för företagens utdelningspolicy, som utvärderas och används som underlag för investeringsbeslut. Att undersöka ett potentiellt samband mellan utdelningspolicy och prisvolatilitet har därför väckt allt större intresse. Bevis för strukturella skillnader på finansmarknaden efter finanskrisen 2008 har även väckt frågan kring huruvida detta samband skiljer sig åt före och efter finanskrisen.

    Syfte: Syftet med denna uppsats är att analysera sambandet mellan utdelningspolicy och aktieprisvolatilitet på den svenska aktiemarknaden.

    Metod: Studien är genomförd utifrån en kvantitativ metod och en deduktiv ansats med en tvärsnittsdesign, där Baskins studie har fungerat som ett metodologiskt ramverk för studien. Faktorerna som har använts för att testa syftet är direktavkastning, utdelningsandel samt återköp. Tillsammans med kontrollvariablerna företagsstorlek, vinstvolatilitet, skuldsättningsgrad och tillväxt analyserades faktorerna genom multipelregressioner. Nödvändiga data hämtades för samtliga noterade bolag på indexet OMXSPI. Det teoretiska ramverk som använts för att analysera resultaten bestod av irrelevansteorin, bird-in-handteorin, livscykelteorin, signalteorin och Baskins mekanismer för utdelningars påverkan på aktieprisvolatiliteten.

    Resultat: Resultatet visar att de oberoende variablerna direktavkastning och utdelningsandel har ett negativt samband med aktieprisvolatilitet. Sambandet har en signifikansnivå på 10% för perioden före och 1% för perioden efter finanskrisen.

    Slutsats: Studien kan konstatera att det finns ett negativt samband mellan högre utdelningspolicy och prisvolatilitet på den svenska marknaden. Att utdelningar i sig har en direkt effekt på prisvolatilitet kan däremot inte säkerställas.

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  • Schildt, Henri
    et al.
    Department of Management Studies, School of Business, Aalto University, Aalto, Finland;Department of Industrial Engineering and Management, School of Science, Aalto University, Finland.
    Lahdenranta, Kristiina
    Department of Management Studies, School of Business, Aalto University, Aalto, Finland.
    Demir, Robert
    Department ofEntrepreneurship and Strategy, Lancaster University Management School, Lancaster, UK.
    Turunen, Taija
    Department of Management Studies, School of Business, Aalto University, Aalto, Finland.
    Waking up to digital innovation: how organisational secrecy hampers top management focus on strategic renewal2024Ingår i: Innovation: Management, Policy & Practice, ISSN 1447-9338, E-ISSN 2204-0226, Vol. 26, nr 4, s. 532-558Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Small and medium-sized firms are increasingly adopting digital technologies to transform themselves. Yet, the ability of top-management teams to embark on strategic transformations depends on entrepreneurial ideas and initiatives that arise across the firm. We conducted a qualitative pre-study of manufacturing companies to understand their challenges in engaging in and implementing digital transformation. The study drew attention to the prevalence of internal secrecy that inhibits knowledge sharing across units and, therefore, complicates the identification and elaboration of customer-centric innovations based on digital data. Building on our initial findings and research, we then developed and tested hypotheses that relate organisational secrecy, competitive pressures, and the range of digital technologies in use to top management’s shift in focus towards digital innovation. We find, in particular, that organisational secrecy impeds a shift in top management attention towards those forms of digital innovation that require complex cross-unit coordination. We also found that perceived external pressures from competition were associated with an increase in top management’s focus on digital innovation. Our study contributes to the literature on digital transformation and strategy processes more generally by elaborating on how organisational secrecy can hamper strategic renewal. The findings suggest that a culture of openness and transparency can facilitate strategic renewal in established companies.

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  • Sowinska, Gabriela
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling.
    Larsson, Jessica
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling.
    AI- ett verktyg eller hinder för revisorn?: En kvantitativ studie kring revisorernas användning av AI och dess påverkan på revisionsprocessen2024Självständigt arbete på avancerad nivå (magisterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Användandet av AI inom revision ska enligt flera studier medföra många fördelar samt vara något som både effektiviserar och förbättrar revisionsprocessen. Däremot verkar användandet ännu vara väldigt begränsat och fenomenet relativt ostuderat i Sverige. 

    Syftet med studien är att analysera och kartlägga i vilken utsträckning artificiell intelligens används av svenska revisorer, samt hur revisorer upplever att revisionsprocessen såväl som revisionskvaliteten påverkas av AI. 

    Studien har en kvantitativ metod och en deduktiv ansats med tvärsnittsdesign. Den data som används i studien utgörs av enkätsvar från revisionsmedarbetare i Sverige. 

    AI används i begränsad uträckning av svenska revisorer och den fas där AI används som mest är granskningsfasen. Därutöver återfinns flera indikationer på att det finns skillnader i upplevelsen av AI gällande dess påverkan på revisonskvaliteten, komforten, effektiviteten samt kompetensen. 

    Studiens bidrag inkluderar en överblick hur användandet av AI ser ut i Sverige, hur revisorerna upplever AI och hur AI påverkar den svenska revisionsprocessen i dagsläget. 

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