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  • Pereira Nielsen, Hugo
    Linköping University, Department of Social and Welfare Studies.
    Arbetet med nyanlända barn i svensk skola: En intervjustudie med sex rektorer2017Independent thesis Basic level (university diploma), 180 HE creditsStudent thesis
  • Gomez, Eliot
    et al.
    Linköping University, Department of Science and Technology. Linköping University, Faculty of Science & Engineering.
    Berggren, Magnus
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Simon, Daniel
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Surface Acoustic Waves to Drive Plant Transpiration.2017In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 7, 45864Article in journal (Refereed)
    Abstract [en]

    Emerging fields of research in electronic plants (e-plants) and agro-nanotechnology seek to create more advanced control of plants and their products. Electronic/nanotechnology plant systems strive to seamlessly monitor, harvest, or deliver chemical signals to sense or regulate plant physiology in a controlled manner. Since the plant vascular system (xylem/phloem) is the primary pathway used to transport water, nutrients, and chemical signals-as well as the primary vehicle for current e-plant and phtyo-nanotechnology work-we seek to directly control fluid transport in plants using external energy. Surface acoustic waves generated from piezoelectric substrates were directly coupled into rose leaves, thereby causing water to rapidly evaporate in a highly localized manner only at the site in contact with the actuator. From fluorescent imaging, we find that the technique reliably delivers up to 6x more water/solute to the site actuated by acoustic energy as compared to normal plant transpiration rates and 2x more than heat-assisted evaporation. The technique of increasing natural plant transpiration through acoustic energy could be used to deliver biomolecules, agrochemicals, or future electronic materials at high spatiotemporal resolution to targeted areas in the plant; providing better interaction with plant physiology or to realize more sophisticated cyborg systems.

  • Hammerman, Madeleine
    Linköping University, Department of Management and Engineering, Commercial and Business Law.
    Reglering av förlängd nätkoncession: En problematisering av hushållningsbestämmelsernas tillämpning och inverkan av bestämmelser om artskydd2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    När energipolitik och reglering av energisektorn diskuteras är det vanligt att störst fokus hamnar på vilken typ av energikälla som används, vilka avgifter energibolagen får ta ut och hur handeln med energiresurser ska hanteras. Dessa är alla viktiga och aktuella frågor i dagens samhälle, där energibehovet ständigt ökar. En ytterligare viktig del av en stats energipolitik är dock hur den infrastrukturella delen av energisektorn regleras. I Sverige kontrolleras byggandet och driften av starkströmsledningar genom nätkoncessioner, vilka meddelas av regeringen eller Energimarknadsinspektionen.

     

    I denna uppsats presenteras en redogörelse över rättsläget vid förlängningsärenden av nätkoncession för linje vilken meddelats för begränsad tid. Läsaren får bekanta sig med begreppet nätkoncession och de rättsliga regleringar vilka är aktuella inom denna del av energisektorn. Problematiken som uppstår i dessa ärenden har kopplingar till den miljörättsliga regleringen och hur dessa bestämmelser ska tillämpas i relation till ellagens bestämmelser. Problematiken grundar sig i tillämpningen av hushållningsbestämmelserna i 3–4 kap. MB och huruvida dessa kan tillämpas på en befintlig verksamhet. Med hänsyn till den aktuella regleringen i ellagen och det bakomliggande syftet med miljöbalken konstateras att en tillämpning av hushållningsbestämmelserna vid förlängningsärenden är möjlig. Konsekvensen av detta blir att en ansökan om förlängning av nätkoncession prövas enligt samma kriterier som en ansökan för ny nätkoncession. Relevant för ämnet är även hur bestämmelser om artskydd ska hanteras av den myndighet som prövar nätkoncessionen. Artskyddet är av intresse eftersom 4 kap. MB hänvisar till de svenska bestämmelserna om Natura 2000, varpå problematiken kring tillämpandet av 3–4 kap. MB även får konsekvenser för artskyddsfrågorna. Även denna utredning stödjer tillämpandet av hushållningsbestämmelserna vid förlängningsärenden med följdfrågan vilken möjlighet nätmyndigheten har att pröva artskyddsfrågorna.

     

    Ett av de största problemen med gällande rätt är hur en förlängningsansökan vilken inkommit efter koncessionstidens utgång ska hanteras. I dessa ärenden går förlängningsmöjligheten förlorad varpå en ansökan om ny nätkoncession måste göras. Eftersom en förlängningsansökan prövas enligt samma kriterier som en ansökan om ny nätkoncession föreslås en lagändring, där förlängningsmöjligheten ersätts med en prövning av ny nätkoncession för befintlig verksamhet. Det nya förfarandet skulle förenkla ansökningsprocessen för nätkoncessioner samt verka för en effektivare hantering av dessa ärenden.

  • Heindoff, Alida
    Linköping University, Department of Management and Engineering, Commercial and Business Law.
    Medvållande genom underlåtenhet att teckna försäkring2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Skadeståndslagens regler om jämkning är till fördel för en skadevållare som blir ålagd skadestånd. Jämkning av skadestånd sker bland annat när den skadelidande har varit medvållande till skadan. I och med bedömning av om förhållanden och omständigheter talar för jämkning, beaktas inblandade parters respektive skuldgrad. Skadeståndet kan sedan jämkas efter vad som är skäligt med hänsyn till graden av vållande på parternas båda sidor. Enligt förarbeten till skadeståndslagen torde underlåtenhet att teckna försäkring kunna leda till jämkning av skadestånd. Den skadelidande får då själv stå en del av kostnaden för den skada som inträffat. Svensk rättspraxis talar dock för att avsaknad av försäkring inte tillmäts någon betydelse i och med jämkningsbedömning. Jämkning av skadestånd torde inte enligt rättspraxis kunna ske utifrån omständigheten att en egendom saknar försäkring. Rättsläget är dock oklart. Frågan om underlåtenhet att teckna försäkring kan omfattas av begreppet medvållande och leda till jämkning, kommer under år 2017 tas upp av Högsta domstolen.

    Det har under lång tid betraktats som god sed att företag tecknar försäkring för sin verksamhet. Företagsförsäkring är en kombinerad försäkring som består av ansvarsförsäkring, egendomsförsäkring och avbrottsförsäkring. Det förväntas att företag har kunskap om vilka försäkringstyper som är kutym inom aktuell bransch och att företaget anskaffar de försäkringar som verksamheten kräver. Försäkringar är idag även vanligt förekommande bland konsumenter. I stort sett alla innehar en hemförsäkring, vari även ansvarsförsäkring ingår. Vill någon försäkra viss specifik egendom krävs ofta tilläggsförsäkring eller egendomsförsäkring. Egendomförsäkring bör vara mindre vanligt än ren hemförsäkring, eftersom hemförsäkringen idag får anses utgöra ett grundskydd som de allra flesta väljer att anskaffa. Fråga är dock huruvida förekomsten av försäkringar och försäkringsskydd är så vanligt förekommande bland konsumenter att det torde betraktas som oaktsamt att underlåta att teckna försäkring?

    Det finns inget lagkrav på tecknande av egendomsförsäkring. Det kan därför till viss del anses vanskligt att förvänta sig eller ta för givet att sådan försäkring föreligger. Många skäl kan ligga till grund för att en person underlåter att teckna försäkring. Underlåtenheten kan exempelvis bero på medvetet risktagande, missuppfattningar, försummelse att förnya försäkring eller brist på försäkringsmöjligheter. Att underlåtenhet att teckna försäkring skulle omfattas av begreppet medvållande och leda till jämkning av skadestånd är således inte helt klart.

    Det finns både fördelar och nackdelar med att underlåtenhet att teckna försäkring skulle falla in under begreppet medvållande och påverka skadeståndets storlek. För skadelidande torde

    fråga uppkomma, om en egendom som saknar försäkring inte ska kunna användas för sitt ändamål, utan risk för att den skadelidande ska belastas med en del av eller hela kostnaden för eventuell skada, som orsakats av utomstående part. En utvidgning av begreppet medvållande skulle kunna medföra att fler väljer att teckna försäkring för att förebygga risken för att bedömas som medvållande. En ökad försäljning av försäkringar leder till ett större försäkringskollektiv och förhoppningsvis en lägre försäkringspremie. För både försäkringsbolag och försäkringstagare bör detta betraktas som positivt. Ett bredare tolkningsutrymme av begreppet innebär dock att begreppet medvållande blir tillämpligt även på förhållanden, handlingar eller rena underlåtenheter som inte direkt bidrar till att skada inträffar eller till skadans omfattning. Agerande eller underlåtenhet som inte har något orsakssamband med skadan kan således komma att leda till jämkning. Om försäkringar har fått en sådan utbredning i samhället att det för vissa typer av egendomar kan betraktas som god sed att teckna försäkring, samt att avsaknad av försäkring anses ha inverkan på skadeståndsstorlek återstår att se. Av svensk rättspraxis finns inte mycket ledning att hämta, en utveckling i rättspraxis är således välkommen. Det bli intressant att se om tvisten som kommer tas upp av HD under år 2017 kan ge ledning i frågan, samt om det är början till en utveckling av synen på försäkringar och dess inverkan på skadeståndsbelopp.

  • Hodzic, Ena
    Linköping University, Department of Management and Engineering, Commercial and Business Law.
    Estetiska krav på en hyreslägenhet?: – Estetisk brist som självständig grund för åtgärdsföreläggande2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    JB 12 kap. 15 och 16 §§ låter sig tolkas på så sätt att eftersatt underhåll självständigt kan ligga till grund för åtgärdsföreläggande. Samtidigt framgår det av rättspraxis att åtgärdsföreläggande endast meddelas för brister som utgör hinder eller men i nyttjanderätten. Med anledning av detta råder oklarheter om hur reglerna för eftersatt underhåll i hyreslägenheter ska tolkas. I uppsatsen utreds om estetiska brister omfattas av det sedvanliga underhållet och om de så- ledes kan utgöra en självständig grund för åtgärdsföreläggande enligt JB 12 kap. 16 § 1 st. 2 p. Motsvarigheten till detta återfinns i JB 12 kap. 24 a §, där hyresvärden kan erhålla ersättning för estetiskt avvikande brister som kan försvåra hyresvärdens framtida uthyrning. Med estetisk brist avses inte en tapet som inte faller den enskilde hyresgästen i smaken utan vad hyresgäster i allmänhet anser vara en estetisk brist. Genom en utförlig utredning av befintliga rättskällor prövas om utrymme finns för en tolkning som innebär att estetiska brister kan utgöra en självständig grund för åtgärdsföreläggande. Förhoppningen är att resultatet ska kunna ge vägledning i liknande spörsmål för på området verksamma jurister. En del argument stödjs på andra källor än rättskällor, eftersom uppsatsen skrivs utifrån en topisk metod. I uppsatsens analyserande del framförs argument som främst talar för att estetiska brister kan utgöra en självständig grund för åtgärdsföreläggande. Resultatet lämnar således utrymme för en alternativ tolkning från den idag rådande tolkningen av JB 12 kap. 15 § 2 st. och 16 § 1 st. 2 p.

  • Svensson, Rebecca
    Linköping University, Department of Management and Engineering, Commercial and Business Law.
    Internprissättning vid utveckling av immateriella tillgångar genom cost contribution arrangements: Nya riktlinjer för deltagare2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Företag inom en koncern kan vid utvecklande av immateriella tillgångar använda sig av cost contribution arrangements för att dela på kostnader och risker samt slippa korslicenser eftersom alla företag i ett CCA får rätt att nyttja tillgångarna. Hur stor del av vinsten som ska fördelas mellan företagen beror på hur mycket de bidrog med vid starten och fördelningen måste överensstämma med armlängdsprincipen. I 14 kap 19 § IL finns en regel som innebär att fördelningen kan korrigeras om det inte överensstämmer med vad ett oberoende företag gått med på under samma förhållanden. OECD:s riktlinjer för internprissättning är vägledande för svensk rätt och den reviderade versionen från 2010 har haft svagheter som företag kunnat utnyttja för att komma undan med oriktiga vinstöverflyttningar till länder med låg skattesats. OECD kom år 2015 ut med den slutgiltiga BEPS-rapporten där åtgärdspunkt 8-10 har som syfte att motverka oriktiga vinstfördelningar genom otillbörliga överflyttningar av risker och immateriella tillgångar mellan företag i intressegemenskap. Åtgärdspunkterna kommer troligtvis göra företag mindre benägna att, samt ge dem mindre möjlighet att, skatteplanera genom att oriktigt flytta vinster till lågskatteländer. Åtgärdspunkterna kommer dock troligtvis medföra fler tvister och nya tolkningsproblem. Målet med åtgärdspunkt 13 är att försäkra att företagen tar hänsyn till de krav som finns för att en transaktion ska vara armländsmässig samt underlätta för Skatteverket att avgöra om transaktionen överensstämmer med armlängdsprincipen. Åtgärdspunkten har fått kritik eftersom den lägger en stor börda på företagen, men OECD hävdar att den på sikt kommer att förenkla för företagen. De nya dokumentationskraven kommer att underlätta för Skatteverket att göra en internprisbedömning och minska möjligheterna att komma undan med felaktiga prissättningar.

  • Thuresson, Björn
    Linköping University, Department of Management and Engineering, Commercial and Business Law.
    Det utvidgade reparationsbegreppet – en utvidgad avdragsrätt, men inte vid förstagångsanpassningar?: En analys av Skatteverkets ställningstagande om förstagångsanpassningar – i förhållande till gällande rätt2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Sedan slutet av 1960-talet har det i lag funnits en avdragsregel som innebär att utgifter, för vissa typer av ändringsarbeten på en byggnad, kan dras av omedelbart, istället för genom årliga värdeminskningsavdrag. Regeln brukar benämnas det ”utvidgade reparationsbegreppet” och återfinns i 19 kap. 2 § 2 st. inkomstskattelagen (1999:1229).

    Efter att många skattskyldiga ansåg att regeln givits en alltför restriktiv tolkning i rättspraxis, genomfördes en lagändring som resulterade i att benämningen i lagtexten ändrades från ”den bedrivna näringsverksamheten” till ”den skattskyldiges näringsverksamhet”. Ändringen innebär att bedömningen av huruvida vidtagna ändringsarbeten kan anses normala i en verksamhet ska göras utifrån antingen fastighetsägarens eller hyresgästens verksamhet, beroende på vem av dem som bekostar arbetena.

    I juni 2016 publicerade Skatteverket ett ställningstagande i vilket redogörs för om utgifter för ändringsarbeten på en byggnad vid en ”förstagångsanpassning” av byggnaden eller dess byggnadsdel (lokal), kan vara omedelbart avdragsgilla enligt det utvidgade reparations-begreppet. Skatteverkets slutsats är att utgifter för ändringsarbeten vid en ”förstagångs-anpassning” inte är omedelbart avdragsgilla. Skatteverket har kritiserats för att i ställningstagandet tolka begreppet ”näringsverksamhet” alltför restriktivt i förhållande till lagstiftarens syfte och gällande rätt i övrigt.

    I föreliggande uppsats studeras det utvidgade reparationsbegreppet närmare med följande övergripande frågeställningar som utgångspunkt: Vad är gällande rätt avseende det utvidgade reparationsbegreppet? Är Skatteverkets ställningstagande och tolkning av begreppet ”näringsverksamhet” förenligt med gällande rätt?

    I uppsatsen kommer författaren fram till slutsatsen att Skatteverkets tolkning av begreppet ”näringsverksamhet” förefaller vara restriktivare än vad lagstiftaren åsyftar. Emellertid finner författaren likaledes att, i brist på prejudikat ifrån HFD, någon definitiv slutsats om huruvida Skatteverkets tolkning överensstämmer med gällande rätt eller ej, inte går att fastställa i dagsläget. Istället får det konstateras att rättsläget tillsvidare är oklart.

  • Tomasin, Marco
    et al.
    University of Padua, Italy; UOS Padova, Italy.
    Mantoan, Elia
    University of Padua, Italy; UOS Padova, Italy.
    Jogenfors, Jonathan
    Linköping University, Department of Electrical Engineering, Information Coding. Linköping University, Faculty of Science & Engineering.
    Vallone, Giuseppe
    University of Padua, Italy; UOS Padova, Italy.
    Larsson, Jan-Åke
    Linköping University, Department of Electrical Engineering, Information Coding. Linköping University, Faculty of Science & Engineering.
    Villoresi, Paolo
    University of Padua, Italy; UOS Padova, Italy.
    High-visibility time-bin entanglement for testing chained Bell inequalities2017In: PHYSICAL REVIEW A, ISSN 2469-9926, Vol. 95, no 3, 032107Article in journal (Refereed)
    Abstract [en]

    The violation of Bells inequality requires a well-designed experiment to validate the result. In experiments using energy-time and time-bin entanglement, initially proposed by Franson in 1989, there is an intrinsic loophole due to the high postselection. To obtain a violation in this type of experiment, a chained Bell inequality must be used. However, the local realism bound requires a high visibility in excess of 94.63% in the time-bin entangled state. In this work, we show how such a high visibility can be reached in order to violate a chained Bell inequality with six, eight, and ten terms.

  • Ipsonius, Birgitta
    Linköping University, Department of Behavioural Sciences and Learning.
    Hur kan förskolemiljön stimulera ett naturvetenskapligt arbetssätt?2014Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Den här studien handlar om arbetet med naturvetenskap och teknik i förskolan. Metoden är

    kvalitativ och syftet är att visa hur pedagoger i förskolan kan integrera de naturvetenskapliga

    ämnena samt teknik i förskolans lärmiljö. Datainsamlingen har skett genom intervjuer,

    dagboksanteckningar samt inventering av en förskolas lärmiljö. Undersökningens resultat

    visar att pedagogers förhållningssätt har stor betydelse då ett naturvetenskapligt arbetssätt

    tillämpas. Studien visar att ett sociokulturellt lärande stämmer väl överens med de delar som

    ger en god grund för att göra naturvetenskap och teknik till en naturlig del av förskolans

    lärmiljö. Om läroplanens intentioner att öka förskolebarns förståelse för och kunskap om de

    naturvetenskapliga ämnena samt teknik skall uppnås behöver dessa ämnen göras till en del av

    förskolans vardag. I uppsatsen tas frågan om pedagogers utbildning och kompetens i de

    naturvetenskapliga ämnena och teknik upp.

  • Nilsson, Sanna
    Linköping University, Department of Culture and Communication.
    Hon är ju ingen Strindberg direkt: En receptionsstudie av fem romaner med bekännelsekaraktär ur genussynpunkt2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Syftet med uppsatsen är att utifrån en jämförelse av fem verk av fyra författare - Karl Ove Knausgård, Lars Norén, Maja Lundgren och Carina Rydberg se huruvida mottagandet skiljer sig åt ur genussynpunkt mellan dessa författares verk som är av liknande karaktär. Detta utförs med hjälp av Yvonne Hirdmans genusteorier och delvis av Ebba Witt-Brattströms teorier om könsanalog läsning. Intresset för detta uppkom utav att Maja Lundgren i synnerhet fick utstå mycket kritik beträffande sin roman "Myggor och tigrar" samtidigt som Lars Norén mestadels hyllades som en stor författare, trots verkens likhet beträffande den utlämnande aspekten.

  • Elfström Pettersson, Katarina
    Linköping University, Department of Social and Welfare Studies, Learning, Aesthetics, Natural science. Linköping University, Faculty of Educational Sciences.
    Teachers’ actions and children’s interests: Quality becomings in preschool documentation2017In: Nordisk Barnehageforskning, ISSN 1890-9167, E-ISSN 1890-9167, Vol. 14, no 2, 1-17 p.Article in journal (Refereed)
    Abstract [en]

    High quality is considered to be important for children’s development and learning in early childhood education. Swedish preschool teachers are required to systematically develop their practice and support children’s learning, using documentation and taking children’s interests into account. From a posthumanist perspective, preschool documentation, models and templates could be seen as actively producing certain elements of quality.  Reading  documentation from eight Swedish preschool groups diffractively through different texts, such as the national curriculum, supportive texts and research, this article discusses how teachers’ actions and children’s interests are produced as important quality aspects in one of these groups.

  • Public defence: 2017-05-19 13:00 Berzeliussalen, Linköping
    Nord, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Divison of Neurobiology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Local Health Care Services in Central Östergötland, Department of Neurology.
    Levodopa pharmacokinetics -from stomach to brain: A study on patients with Parkinson’s disease2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Parkinson’s disease (PD) is one of the most common neurodegenerative disorders and it is caused by a loss of dopamine (DA) producing neurons in the basal ganglia in the brain. The PD patient suffers from motor symptoms such as tremor, bradykinesia and rigidity and treatment with levodopa (LD), the precursor of DA, has positive effects on these symptoms. Several factors affect the availability of orally given LD. Gastric emptying (GE) is one factor and it has been shown to be delayed in PD patients resulting in impaired levodopa uptake. Different enzymes metabolize LD on its way from the gut to the brain resulting in less LD available in the brain and more side effects from the metabolites. By adding dopa decarboxylase inhibitors (carbidopa or benserazide) or COMT-inhibitors (e.g. entacapone) the bioavailability of LD increases significantly and more LD can pass the blood-brain-barrier and be converted to DA in the brain. It has been considered of importance to avoid high levodopa peaks in the brain because this seems to induce changes in postsynaptic dopaminergic neurons causing disabling motor complications in PD patients. More continuously given LD, e.g. duodenal or intravenous (IV) infusions, has been shown to improve these motor complications. Deep brain stimulation of the subthalamic nucleus (STN DBS) has also been proven to improve motor complications and to make it possible to reduce the LD dosage in PD patients.

    In this doctoral thesis the main purpose is to study the pharmacokinetics of LD in patients with PD and motor complications; in blood and subcutaneous tissue and study the effect of GE and PD stage on LD uptake and the effect of continuously given LD (CDS) on LD uptake and GE; in blood and cerebrospinal fluid (CSF) when adding the peripheral enzyme inhibitors entacapone and carbidopa to LD infusion IV; in brain during STN DBSand during oral or IV LD treatment.

    To conclude, LD uptake is more favorable in PD patients with less severe disease and GE is delayed in PD patients. No obvious relation between LD uptake and GE or between GE and PD stage is seen and CDS decreases the LD levels. Entacapone increases the maximal concentration of LD in blood and CSF. This is more evident with additional carbidopa and important to consider in avoiding high LD peaks in brain during PD treatment. LD in brain increases during both oral and IV LD treatment and the DA levels follows LD well indicating that PD patients still have capacity to metabolize LD to DA despite probable pronounced nigral degeneration. STN DBS seems to increase putaminal DA levels and together with IV LD treatment also increases LD in brain possibly explaining why it is possible to decrease LD medication after STN DBS surgery.

    List of papers
    1. Is Levodopa Pharmacokinetics in Patients with Parkinson’s Disease Depending on Gastric Emptying?
    Open this publication in new window or tab >>Is Levodopa Pharmacokinetics in Patients with Parkinson’s Disease Depending on Gastric Emptying?
    2017 (English)In: Advances in Parkinsons Disease, ISSN 2169-9712, Vol. 06, no 01Article in journal (Refereed) Published
    Abstract [en]

    Levodopa uptake from the gastrointestinal tract in patients with Parkinson’s disease (PD) can be affected by delayed gastric emptying (GE). This might lead to fluctuating levodopa levels resulting in increased motor fluctuations. Continuous dopaminergic stimulation (CDS) improves motor fluctuations and could be a result of smoothening in levodopa uptake. In this study we wanted to study the levodopa pharmacokinetics peripherally in PD patients with motor fluctuations and investigate the relation between levodopa uptake and GE and the effect of CDS. PD patients with wearing off (group 1) and on-off syndrome (group 2) were included. Breath tests were performed to evaluate the half time (T1/2) of GE. Concomitantly 1 tablet of Madopark® was given and the levodopa concentrations in blood and subcutaneous (SC) tissue were analyzed for both groups. Group 2 was then given a 10-d continuous intravenous levodopa treatment and the tests were repeated. Higher levels of levodopa in group 1 compared to group 2 in blood (p = 0.014) were seen. The GE was delayed in both group 1 (p < 0.001) and group 2 (p < 0.05) compared to a reference group with healthy volunteers with T1/2 median values 105 and 78 min vs. 72 min. There was no difference in GE between the two PD groups (p = 0.220) or in group 2 before and after infusion period (p = 0.861). CDS resulted in lower levodopa levels in blood (p < 0.001) and SC tissue (p < 0.01). In conclusion, PD patients in early complication phase have a more favourable levodopa uptake than patients later in disease. We found delayed GE in PD patients with motor fluctuations but no obvious relation between GE and levodopa uptake or GE and PD stage. The effect of CDS indicates no effect of CDS on the mechanisms of GE but on the mechanisms of levodopa uptake.

    Place, publisher, year, edition, pages
    Scientific Research Publishing, 2017
    National Category
    Neurology Gastroenterology and Hepatology Anesthesiology and Intensive Care Surgery Cardiac and Cardiovascular Systems
    Identifiers
    urn:nbn:se:liu:diva-136685 (URN)10.4236/apd.2017.61001 (DOI)
    Available from: 2017-04-20 Created: 2017-04-20 Last updated: 2017-04-20
    2. The Effect of Peripheral Enzyme Inhibitors on Levodopa Concentrations in Blood and CSF
    Open this publication in new window or tab >>The Effect of Peripheral Enzyme Inhibitors on Levodopa Concentrations in Blood and CSF
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    2010 (English)In: MOVEMENT DISORDERS, ISSN 0885-3185, Vol. 25, no 3, 363-367 p.Article in journal (Refereed) Published
    Abstract [en]

    Levodopa combined with a dopa-decarboxylase inhibitor, such as carbidopa. shifts the metabolism to the COMT pathway. Adding the peripheral acting COMT inhibitor entacapone provides improvement for patients with PD suffering from motor fluctuations. We studied the effects of the enzyme inhibitors entacapone and carbidopa on the levodopa concentrations in CSF and in blood. Five PD patients with wearing-off underwent lumbar drainage and intravenous microdialysis. Samples were taken 12 h daily for 3 days. Day I; intravenous levodopa was given, day 2; additional oral entacapone 200 mg tid, day 3; additional oral entacapone 200 mg bid and carbidopa 25 mg bid. Levodopa in CSF and in dialysates was analysed. The AUC for levodopa increased both in blood and CSF when additional entacapone was given alone and in combination with carbidopa. The C-max of levodopa in both CSF and blood increased significantly. Additional entacapone to levodopa therapy gives an increase of C-max in CSF and in blood. The increase is more evident when entacapone is combined with carbidopa.

    Place, publisher, year, edition, pages
    John Wiley and Sons, Ltd, 2010
    Keyword
    Parkinsons Disease, levodopa, continuous infusion, COMT
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-54855 (URN)10.1002/mds.22613 (DOI)000276136900016 ()
    Available from: 2010-04-16 Created: 2010-04-16 Last updated: 2017-04-20
    3. Neurotransmitter levels in basal ganglia during levodopa and deep brain stimulation treatment in Parkinson’s disease
    Open this publication in new window or tab >>Neurotransmitter levels in basal ganglia during levodopa and deep brain stimulation treatment in Parkinson’s disease
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    2014 (English)In: Neurology and Clinical Neuroscience, ISSN 2049-4173, Vol. 2, no 5, 149-155 p.Article in journal (Refereed) Published
    Abstract [en]

    Background The mechanism by which deep brain stimulation of the nucleus subthalamicus improves Parkinson’s disease symptoms remains unclear. In a previous perioperative study, we showed that there might be alterations of neurotransmitter levels in the globus pallidum interna during deep brain stimulation of the nucleus subthalamicus. Aim In this study, we examined whether deep brain stimulation of the nucleus subthalamicus and levodopa infusion interact and affect the levels of neurotransmitters. Methods Five patients with advanced Parkinson’s disease took part in the study. During subthalamic nucleus surgery, microdialysis catheters were inserted bilaterally in the globus pallidum interna and unilaterally in the right putamen. A study protocol was set up and was followed for 3 days. Levodopa infusion with and without concomitant bilateral deep brain stimulation of the nucleus subthalamicus was also carried out. Results The putaminal dopamine levels increased during deep brain stimulation of the nucleus subthalamicus. In addition, an increase of gamma amino buturic acid concentrations in the globus pallidum interna during deep brain stimulation of the nucleus subthalamicus and during levodopa infusion was found. Conclusions These findings provide evidence that the subthalamic nucleus has a direct action on the substantia nigra pars compacta, and that deep brain stimulation of the nucleus subthalamicus might indirectly release putaminal dopamine. There is also evidence that deep brain stimulation of the nucleus subthalamicus interferes with levodopa therapy resulting in higher levels of levodopa in the brain, explaining why it is possible to decrease levodopa medication after deep brain stimulation surgery.

    Place, publisher, year, edition, pages
    John Wiley & Sons, 2014
    Keyword
    deep brain stimulation, levodopa, microdialysis, neurotransmitters, Parkinson
    National Category
    Medical Bioscience Medical Biotechnology Basic Medicine
    Identifiers
    urn:nbn:se:liu:diva-113590 (URN)10.1111/ncn3.109 (DOI)
    Available from: 2015-01-23 Created: 2015-01-23 Last updated: 2017-04-20Bibliographically approved
  • Nordlander Wiik, Marcus
    Linköping University, Department of Management and Engineering, Information Systems.
    Utvecklarmedverkan: Ett annorlunda perspektiv på relationen mellan utvecklare och användare: En undersökning över hur utvecklare kan involveras i användarens verksamhet2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    It is not a new thing for developers and users to work together in system development projects for the projects to succeed. This collaboration comes from what is known as the Scandinavian approach. This refers to a progress that took place in and was dominant in Scandinavia where codetermination in the workplace became important and they started to involve users in the decisions regarding new computer systems. The Scandinavian approach is the origin of user participation, which is well used today and almost considered necessary to reach success in system development. User participation stands for the participation of users in activities during the development. User participation is well researched and acknowledged to contribute to successful development projects.

    Although user participation has become established most of system development projects does not end in success. Often the systems don’t meet the needs of the users and there’s also often no one with influence that sees to their interests. This leads to the question if collaboration between developers and users could be done by other means, as a way to identify business needs and reach successful IT-solutions. Because of this, this study introduces and explores the possibilities surrounding the concept developer participation. Developer participation stands for the participation of developers in the user’s activities. This presents a new way to look at it with a new focus on the users which means collaboration where the users have the power to influence. In extension of this objective the study was set to answer these three research questions; How can developers participate in the users business?, What benefits can the participation lead to?, What challenges can the participation face?.

    The study was carried out with a qualitative approach where data was collected through literature and semi-structured interviews. The study was conducted with help from a consultant company which accounted for the interviewees through their staff and customer base. With a thematic coding as the analytic method the study concludes that developer participation face mainly two challenges. It means that a new approach where quite different people have to collaborate are introduced and this approach has to be proven worth the time and money it takes to use it. Furthermore the study presents a greater understanding between developers and users and an opportunity for organizational improvements on the user side as possible effects of developer participation.         

  • Public defence: 2017-05-19 09:00 Belladonnan, Linköping
    Spreco, Armin
    Linköping University, Department of Medical and Health Sciences, Division of Community Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Epidemiological and statistical basis for detection and prediction of influenza epidemics2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    A large number of emerging infectious diseases (including influenza epidemics) has been identified during the last century. The emergence and re-emergence of infectious diseases have a negative impact on global health. Influenza epidemics alone cause between 3 and 5 million cases of severe illness annually, and between 250,000 and 500,000 deaths. In addition to the human suffering, influenza epidemics also impose heavy demands on the health care system. For example, hospitals and intensive care units have limited excess capacity during infectious diseases epidemics. Therefore, it is important that increased influenza activity is noticed early at local levels to allow time to adjust primary care and hospital resources that are already under pressure. Algorithms for the detection and prediction of influenza epidemics are essential components to achieve this.

    Although a large number of studies have reported algorithms for detection or prediction of influenza epidemics, outputs that fulfil standard criteria for operational readiness are seldom produced. Furthermore, in the light of the rapidly growing availability of “Big Data” from both diagnostic and prediagnostic (syndromic) data sources in health care and public health settings, a new generation of epidemiologic and statistical methods, using several data sources, is desired for reliable analyses and modeling.

    The rationale for this thesis was to inform the planning of local response measures and adjustments to health care capacity during influenza epidemics. The overall aim was to develop a method for detection and prediction of influenza epidemics. Before developing the method, three preparatory studies were performed. In the first of these studies, the associations (in terms of correlation) between diagnostic and pre-diagnostic data sources were examined, with the aim of investigating the potential of these sources for use in influenza surveillance systems. In the second study, a literature study of detection and prediction algorithms used in the field of influenza surveillance was performed. In the third study, the algorithms found in the previous study were compared in a prospective evaluation study. In the fourth study, a method for nowcasting of influenza activity was developed using electronically available data for real-time surveillance in local settings followed by retrospective application on the same data. This method includes three functions: detection of the start of the epidemic at the local level and predictions of the peak timing and the peak intensity. In the fifth and final study, the nowcasting method was evaluated by prospective application on authentic data from Östergötland County, Sweden.

    In the first study, correlations with large effect sizes between diagnostic and pre-diagnostic data were found, indicating that pre-diagnostic data sources have potential for use in influenza surveillance systems. However, it was concluded that further longitudinal research incorporating prospective evaluations is required before these sources can be used for this purpose. In the second study, a meta-narrative review approach was used in which two narratives for reporting prospective evaluation of influenza detection and prediction algorithms were identified: the biodefence informatics narrative and the health policy research narrative. As a result of the promising performances of one detection algorithm and one prediction algorithm in the third study, it was concluded that both further evaluation research and research on methods for nowcasting of influenza activity were warranted. In the fourth study, the performance of the nowcasting method was promising when applied on retrospective data but it was concluded that thorough prospective evaluations are necessary before recommending the method for broader use. In the fifth study, the performance of the nowcasting method was promising when prospectively applied on authentic data, implying that the method has potential for routine use. In future studies, the validity of the nowcasting method must be investigated by application and further evaluation in multiple local settings, including large urbanizations.

    List of papers
    1. Performance of eHealth data sources in local influenza surveillance: a 5-year open cohort study
    Open this publication in new window or tab >>Performance of eHealth data sources in local influenza surveillance: a 5-year open cohort study
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    2014 (English)In: Journal of Medical Internet Research, ISSN 1438-8871, Vol. 16, no 4, e116- p.Article in journal (Refereed) Published
    Abstract [en]

    BACKGROUND: There is abundant global interest in using syndromic data from population-wide health information systems--referred to as eHealth resources--to improve infectious disease surveillance. Recently, the necessity for these systems to achieve two potentially conflicting requirements has been emphasized. First, they must be evidence-based; second, they must be adjusted for the diversity of populations, lifestyles, and environments.

    OBJECTIVE: The primary objective was to examine correlations between data from Google Flu Trends (GFT), computer-supported telenursing centers, health service websites, and influenza case rates during seasonal and pandemic influenza outbreaks. The secondary objective was to investigate associations between eHealth data, media coverage, and the interaction between circulating influenza strain(s) and the age-related population immunity.

    METHODS: An open cohort design was used for a five-year study in a Swedish county (population 427,000). Syndromic eHealth data were collected from GFT, telenursing call centers, and local health service website visits at page level. Data on mass media coverage of influenza was collected from the major regional newspaper. The performance of eHealth data in surveillance was measured by correlation effect size and time lag to clinically diagnosed influenza cases.

    RESULTS: Local media coverage data and influenza case rates showed correlations with large effect sizes only for the influenza A (A) pH1N1 outbreak in 2009 (r=.74, 95% CI .42-.90; P<.001) and the severe seasonal A H3N2 outbreak in 2011-2012 (r=.79, 95% CI .42-.93; P=.001), with media coverage preceding case rates with one week. Correlations between GFT and influenza case data showed large effect sizes for all outbreaks, the largest being the seasonal A H3N2 outbreak in 2008-2009 (r=.96, 95% CI .88-.99; P<.001). The preceding time lag decreased from two weeks during the first outbreaks to one week from the 2009 A pH1N1 pandemic. Telenursing data and influenza case data showed correlations with large effect sizes for all outbreaks after the seasonal B and A H1 outbreak in 2007-2008, with a time lag decreasing from two weeks for the seasonal A H3N2 outbreak in 2008-2009 (r=.95, 95% CI .82-.98; P<.001) to none for the A p H1N1 outbreak in 2009 (r=.84, 95% CI .62-.94; P<.001). Large effect sizes were also observed between website visits and influenza case data.

    CONCLUSIONS: Correlations between the eHealth data and influenza case rates in a Swedish county showed large effect sizes throughout a five-year period, while the time lag between signals in eHealth data and influenza rates changed. Further research is needed on analytic methods for adjusting eHealth surveillance systems to shifts in media coverage and to variations in age-group related immunity between virus strains. The results can be used to inform the development of alert-generating eHealth surveillance systems that can be subject for prospective evaluations in routine public health practice.

    Place, publisher, year, edition, pages
    Journal of Medical Internet Research, 2014
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-106758 (URN)10.2196/jmir.3099 (DOI)000336501600017 ()24776527 (PubMedID)
    Available from: 2014-05-21 Created: 2014-05-21 Last updated: 2017-04-19Bibliographically approved
    2. Algorithms for detecting and predicting influenza outbreaks: metanarrative review of prospective evaluations
    Open this publication in new window or tab >>Algorithms for detecting and predicting influenza outbreaks: metanarrative review of prospective evaluations
    2016 (English)In: BMJ Open, ISSN 2044-6055, E-ISSN 2044-6055, Vol. 6, no 5, e010683- p.Article, review/survey (Refereed) Published
    Abstract [en]

    Objectives Reliable monitoring of influenza seasons and pandemic outbreaks is essential for response planning, but compilations of reports on detection and prediction algorithm performance in influenza control practice are largely missing. The aim of this study is to perform a metanarrative review of prospective evaluations of influenza outbreak detection and prediction algorithms restricted settings where authentic surveillance data have been used. Design The study was performed as a metanarrative review. An electronic literature search was performed, papers selected and qualitative and semiquantitative content analyses were conducted. For data extraction and interpretations, researcher triangulation was used for quality assurance. Results Eight prospective evaluations were found that used authentic surveillance data: three studies evaluating detection and five studies evaluating prediction. The methodological perspectives and experiences from the evaluations were found to have been reported in narrative formats representing biodefence informatics and health policy research, respectively. The biodefence informatics narrative having an emphasis on verification of technically and mathematically sound algorithms constituted a large part of the reporting. Four evaluations were reported as health policy research narratives, thus formulated in a manner that allows the results to qualify as policy evidence. Conclusions Awareness of the narrative format in which results are reported is essential when interpreting algorithm evaluations from an infectious disease control practice perspective.

    Place, publisher, year, edition, pages
    BMJ PUBLISHING GROUP, 2016
    Keyword
    influenza; detection algorithms; prediction algorithms; evaluation; meta-narrative review
    National Category
    Health Care Service and Management, Health Policy and Services and Health Economy
    Identifiers
    urn:nbn:se:liu:diva-130311 (URN)10.1136/bmjopen-2015-010683 (DOI)000378414700068 ()27154479 (PubMedID)
    Note

    Funding Agencies|Swedish Civil Contingencies Agency [2010-2788]; Swedish Science Council [2008-5252]

    Available from: 2016-07-31 Created: 2016-07-28 Last updated: 2017-04-19
  • Public defence: 2017-05-23 13:15 Eken, Linköping
    Forsgren, Mikael
    Linköping University, Department of Medical and Health Sciences, Division of Radiological Sciences. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Radiation Physics. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    The Non-Invasive Liver Biopsy: Determining Hepatic Function in Diffuse and Focal LiverDisease2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The liver is one of the largest organs within the human body and it handles many vital tasks such as nutrient processing, toxin removal, and synthesis of important proteins. The number of people suffering from chronic liver disease is on the rise, likely due to the present ‘western’ lifestyle. As disease develops in the liver there are pathophysiological manifestations within the liver parenchyma that are both common and important to monitor. These manifestations include inflammation, fatty infiltration (steatosis), excessive scar tissue formation (fibrosis and cirrhosis), and iron loading. Importantly, as the disease progresses there is concurrent loss of liver function. Furthermore, postoperative liver function insufficiency is an important concern when planning surgical treatment of the liver, because it is associated with both morbidity and mortality. Liver function can also be hampered due to drug-induced injuries, an important aspect to consider in drug-development.

    Currently, an invasive liver needle biopsy is required to determine the aetiology and to stage or grade the pathophysiological manifestations. There are important limitations with the biopsy, which include, risk of serious complications, mortality, morbidity, inter- and intra-observer variability, sampling error, and sampling variability. Cleary, it would be beneficial to be able investigate the pathophysiological manifestations accurately, non-invasively, and on regional level.

    Current available laboratory liver function blood panels are typically insufficient and often only indicate damage at a late stage. Thus, it would be beneficial to have access to biomarkers that are both sensitive and responds to early changes in liver function in both clinical settings and for the pharmaceutical industry and regulatory agencies.

    The main aim of this thesis was to develop and evaluate methods that can be used for a ‘non-invasive liver biopsy’ using magnetic resonance (MR). We also aimed to develop sensitive methods for measure liver function based on gadoxetate-enhanced MR imaging (MRI).

    The presented work is primarily based on a prospective study on c. 100 patients suffering from chronic liver disease of varying aetiologies recruited due to elevated liver enzyme levels, without clear signs of decompensated cirrhosis. Our results show that the commonly used liver fat cut-off for diagnosing steatosis should be lowered from 5% to 3% when using MR proton-density fat fraction (PDFF). We also show that MR elastography (MRE) is superior in staging fibrosis.

    Finally we presented a framework for quantifying liver function based on gadoxetate-enhanced MRI. The method is based on clinical images and a clinical approved contrast agent (gadoxetate). The framework consists of; state-of the-art image reconstruction and correction methods, a mathematical model, and a precise model parametrization method. The model was developed and validated on healthy subjects. Thereafter the model was found applicable on the chronic liver disease cohort as well as validated using gadoxetate levels in biopsy samples and blood samples. The liver function parameters correlated with clinical markers for liver function and liver fibrosis (used as a surrogate marker for liver function).

    In summary, it should be possible to perform a non-invasive liver biopsy using: MRI-PDFF for liver fat and iron loading, MRE for liver fibrosis and possibly also inflammation, and measure liver function using the presented framework for analysing gadoxetate-enhanced MRI. With the exception of an MREtransducer no additional hardware is required on the MR scanner. The liver function method is likely to be useful both in a clinical setting and in pharmaceutical trials.

    List of papers
    1. Separation of advanced from mild hepatic fibrosis by quantification of the hepatobiliary uptake of Gd-EOB-DTPA
    Open this publication in new window or tab >>Separation of advanced from mild hepatic fibrosis by quantification of the hepatobiliary uptake of Gd-EOB-DTPA
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    2013 (English)In: European Radiology, ISSN 0938-7994, E-ISSN 1432-1084, Vol. 23, no 1, 174-181 p.Article in journal (Refereed) Published
    Abstract [en]

    Objectives

    To apply dynamic contrast-enhanced (DCE) MRI on patients presenting with elevated liver enzymes without clinical signs of hepatic decompensation in order to quantitatively compare the hepatocyte-specific uptake of Gd-EOB-DTPA with histopathological fibrosis stage.

    Methods

    A total of 38 patients were prospectively examined using 1.5-T MRI. Data were acquired from regions of interest in the liver and spleen by using time series of single-breath-hold symmetrically sampled two-point Dixon 3D images (non-enhanced, arterial and venous portal phase; 3, 10, 20 and 30 min) following a bolus injection of Gd-EOB-DTPA (0.025 mmol/kg). The signal intensity (SI) values were reconstructed using a phase-sensitive technique and normalised using multiscale adaptive normalising averaging (MANA). Liver-to-spleen contrast ratios (LSC_N) and the contrast uptake rate (KHep) were calculated. Liver biopsy was performed and classified according to the Batts and Ludwig system.

    Results

    Area under the receiver-operating characteristic curve (AUROC) values of 0.71, 0.80 and 0.78, respectively, were found for KHep, LSC_N10 and LSC_N20 with regard to severe versus mild fibrosis. Significant group differences were found for KHep (borderline), LSC_N10 and LSC_N20.

    Conclusions

    Liver fibrosis stage strongly influences the hepatocyte-specific uptake of Gd-EOB-DTPA. Potentially the normalisation technique and KHep will reduce patient and system bias, yielding a robust approach to non-invasive liver function determination.

    Place, publisher, year, edition, pages
    Springer, 2013
    Keyword
    Quantification, Gd-EOB-DTPA, Dynamic contrast-enhanced MRI, Pharmacokinetics, Liver
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-87242 (URN)10.1007/s00330-012-2583-2 (DOI)000312324500022 ()
    Projects
    NILB
    Note

    Funding Agencies|Swedish Research Council|VR/M 2007-2884|Medical Research Council of South-east Sweden|FORSS 12621|Linkoping University, Linkoping University Hospital Research Foundations||County Council of Ostergotland||

    Available from: 2013-01-14 Created: 2013-01-14 Last updated: 2017-04-19
    2. Physiologically Realistic and Validated Mathematical Liver Model Revels Hepatobiliary Transfer Rates for Gd-EOB-DTPA Using Human DCE-MRI Data
    Open this publication in new window or tab >>Physiologically Realistic and Validated Mathematical Liver Model Revels Hepatobiliary Transfer Rates for Gd-EOB-DTPA Using Human DCE-MRI Data
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    2014 (English)In: PLoS ONE, ISSN 1932-6203, Vol. 9, no 4, 0095700- p.Article in journal (Refereed) Published
    Abstract [en]

    Objectives: Diffuse liver disease (DLD), such as non-alcoholic fatty liver disease (NASH) and cirrhosis, is a rapidly growing problem throughout the Westernized world. Magnetic resonance imaging (MRI), based on uptake of the hepatocyte-specific contrast agent (CA) Gd-EOB-DTPA, is a promising non-invasive approach for diagnosing DLD. However, to fully utilize the potential of such dynamic measurements for clinical or research purposes, more advanced methods for data analysis are required. Methods: A mathematical model that can be used for such data-analysis was developed. Data was obtained from healthy human subjects using a clinical protocol with high spatial resolution. The model is based on ordinary differential equations and goes beyond local diffusion modeling, taking into account the complete system accessible to the CA. Results: The presented model can describe the data accurately, which was confirmed using chi-square statistics. Furthermore, the model is minimal and identifiable, meaning that all parameters were determined with small degree of uncertainty. The model was also validated using independent data. Conclusions: We have developed a novel approach for determining previously undescribed physiological hepatic parameters in humans, associated with CA transport across the liver. The method has a potential for assessing regional liver function in clinical examinations of patients that are suffering of DLD and compromised hepatic function.

    Place, publisher, year, edition, pages
    Public Library of Science, 2014
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-106962 (URN)10.1371/journal.pone.0095700 (DOI)000335226500139 ()
    Available from: 2014-06-04 Created: 2014-06-02 Last updated: 2017-04-19
    3. Using a 3% Proton Density Fat Fraction as a Cut-off Value Increases Sensitivity of Detection of Hepatic Steatosis, Based on Results from Histopathology Analysis
    Open this publication in new window or tab >>Using a 3% Proton Density Fat Fraction as a Cut-off Value Increases Sensitivity of Detection of Hepatic Steatosis, Based on Results from Histopathology Analysis
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    2017 (English)In: Gastroenterology, ISSN 0016-5085, E-ISSN 1528-0012, StartPage-EndPage p.Article in journal (Refereed) Epub ahead of print
    Abstract [en]

    It is possible to estimate hepatic triglyceride content by calculating the proton density fat fraction (PDFF), using proton magnetic resonance spectroscopy (less thansuperscriptgreater than1less than/superscriptgreater thanH-MRS), instead of collecting and analyzing liver biopsies to detect steatosis. However, the current PDFF cut-off value (5%) used to define steatosis by magnetic resonance was derived from studies that did not use histopathology as the reference standard. We performed a prospective study to determine the accuracy of less thansuperscriptgreater than1less than/superscriptgreater thanH-MRS PDFF in measurement of steatosis using histopathology analysis as the standard. We collected clinical, serologic, less thansuperscriptgreater than1less than/superscriptgreater thanH-MRS PDFF, and liver biopsy data from 94 adult patients with increased levels of liver enzymes (6 months or more) referred to the Department of Gastroenterology and Hepatology at Linköping University Hospital in Sweden from 2007 through 2014. Steatosis was graded using the conventional histopathology method and fat content was quantified in biopsy samples using stereological point counts (SPCs). We correlated less thansuperscriptgreater than1less than/superscriptgreater thanH-MRS PDFF findings with SPCs (r = 0.92; P less than.001). less thansuperscriptgreater than1less than/superscriptgreater thanH-MRS PDFF results correlated with histopathology results (ρ = 0.87; P less than.001), and SPCs correlated with histopathology results (ρ = 0.88; P less than.001). All 25 subjects with PDFF values of 5.0% or more had steatosis based on histopathology findings (100% specificity for PDFF). However, of 69 subjects with PDFF values below 5.0% (negative result), 22 were determined to have steatosis based on histopathology findings (53% sensitivity for PDFF). Reducing the PDFF cut-off value to 3.0% identified patients with steatosis with 100% specificity and 79% sensitivity; a PDFF cut-off value of 2.0% identified patients with steatosis with 94% specificity and 87% sensitivity. These findings might be used to improve non-invasive detection of steatosis.

    Place, publisher, year, edition, pages
    Elsevier, 2017
    National Category
    Gastroenterology and Hepatology
    Identifiers
    urn:nbn:se:liu:diva-136544 (URN)10.1053/j.gastro.2017.03.005 (DOI)
    Available from: 2017-04-19 Created: 2017-04-19 Last updated: 2017-04-19Bibliographically approved
  • Eklund, Anders
    et al.
    Linköping University, Department of Biomedical Engineering, Division of Biomedical Engineering. Linköping University, Department of Computer and Information Science, Statistics. Linköping University, Faculty of Science & Engineering. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Nichols, Thomas
    Department of Statistics, University of Warwick, UK / WMG, University of Warwick, UK.
    Knutsson, Hans
    Linköping University, Department of Biomedical Engineering, Division of Biomedical Engineering. Linköping University, Faculty of Science & Engineering. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Reply to BROWN AND BEHRMANN, COX ET AL., AND KESSLER ET AL.: Data and code sharing is the way forward for fMRI2017In: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, 1-2 p.Article in journal (Refereed)
    Abstract [en]

    We are glad that our paper (1) has generated intense discussions in the fMRI field (2⇓–4), on how to analyze fMRI data, and how to correct for multiple comparisons. The goal of the paper was not to disparage any specific fMRI software, but to point out that parametric statistical methods are based on a number of assumptions that are not always valid for fMRI data, and that nonparametric statistical methods (5) are a good alternative. Through AFNI’s introduction of nonparametric statistics in the function 3dttest++ (3, 6), the three most common fMRI softwares now all support nonparametric group inference [SPM through the toolbox SnPM (www2.warwick.ac.uk/fac/sci/statistics/staff/academic-research/nichols/software/snpm), and FSL through the function randomise].

    Cox et al. (3) correctly point out that the bug in the AFNI function 3dClustSim only had a minor impact on the false-positive rate (FPR). This was also covered in our original paper (1): “We note that FWE [familywise error] rates are lower with the bug-fixed 3dClustSim function. As an example, the updated function reduces the degree of false …

  • Erlingsson, Gissur Ó
    et al.
    Linköping University, Department for Studies of Social Change and Culture, Centre for Municipality Studies – CKS. Linköping University, Faculty of Arts and Sciences.
    Öhrvall, Richard
    Linköping University, Department of Management and Engineering, Political Science. Linköping University, Faculty of Arts and Sciences.
    Fullmäktigeledamoten och mandatperioden2017Report (Other academic)
    Abstract [sv]

    Denna rapport utgör den andra rapporten i ett större forskningsprojekt om för-troendevaldas villkor i kommunpolitiken, ett projekt med särskilt fokus på indi-vider som för första gången fick ett förtroendeuppdrag i samband med valet 2014. Det övergripande syftet med föreliggande rapport är att uppmärksamma om erfarenheten av att komma in som ny i kommunpolitiken påverkar den nya politikerns syn på kommunpolitiken, på sig själv och sina möjligheter att på-verka. Utöver detta har vi också undersökt andra frågor, bland annat politi-kernas syn på förutsättningar att fullgöra uppdraget, liksom olika aspekter av den lokala demokratin.

    Kommunpolitiker mindre nöjda med demokratin

    När kommunpolitiker får ange hur pass nöjda de är med demokratin på olika politiska nivåer, är det anmärkningsvärt att kommunpolitikerna själva är mindre nöjda med demokratin än vad medborgarna är. Detta gäller samtliga politiska nivåer (kommuner, landsting/region, riksnivå och EU), även om skillnaden är minst uttalad på lokal nivå. En ytterligare skillnad är att medborgarna rankar demokratin i riket som helhet högst, medan kommunpolitiker är mest nöjda med demokratin på lokal nivå.

    Medborgarna anses ha för lite makt, tjänstemännen för mycket

    I studien har vi ställt frågor om vem eller vilka våra respondenter anser har makten i kommunen, och vem eller vilka som bör ha den. Två grupper står särskilt ut vad gäller glappet mellan vilka som har makt och vilka som borde ha makt. Medborgarna uppfattas ha väldigt lite makt i förhållande till hur mycket makt de borde ha. Det omvända förhållandet gäller tjänstemännen som upp-fattas ha mycket mer makt än vad de borde ha.

    Erfarenheten av fullmäktigeuppdrag stärker inte självförtroendet

    Vi har undersökt vad erfarenheten av att vara förtroendevald gör med det egna politiska självförtroendet. Frågan är intressant på ett generellt plan. I litteraturen om politiskt deltagande återfinns nämligen antagandet att ju mer man deltar po-litiskt i gemensamma angelägenheter, desto mer stärks det personliga politiska självförtroendet. Genom att jämföra respondenternas svar i den enkätomgång vi skickade ut före valet 2014, med deras svar ungefär halvvägs in i mandat-perioden, finner vi inget stöd för en sådan tes. Det politiska självförtroendet, åtminstone som vi försöker mäta det, stärks inte. Snarare tycks det försvagas i olika avseenden från första mättillfället till mitten av mandatperioden. Istället framträder en bild av politiker som i stort sett genomgående tycks bli något mer desillusionerade ju längre mandatperioden går. Men detta gäller, måhända över-raskande, inte bara nya politiker utan gäller också mer erfarna politiker.

    Realistiska uppfattningar om tidsåtgång, men oförstående arbetskamrater

    Vi har också ställt en rad frågor för att ta reda på hur krävande ett politiskt för-troendeuppdrag kan sägas vara utifrån olika aspekter, där syftet har varit att för-söka identifiera potentiella faktorer som bidrar till vantrivsel eller förtida av-hopp. Två saker är särskilt värda att understryka: För det första, när vi jämför vilken förväntad tidsåtgång våra respondenter trodde att deras uppdrag skulle ta inför valet 2014, med vilken faktiskt tid uppdraget tar mitt i mandatperioden, finner vi att mer erfarna politiker i dag lägger ned ungefär lika många timmar på uppdraget som de trodde att uppdraget skulle kräva; medan nya politiker lägger ned något färre timmar än vad de trodde de skulle göra. Med andra ord tycks förväntningarna om tidsåtgången ha varit tämligen rimliga, och i vart fall är det inte så att nya politiker underskattat hur mycket tid de skulle bli tvungna att lägga ned på uppdraget. För det andra, en faktor som mer eller mindre explicit kan verka hämmande för viljan och möjligheten att vara förtroendevald, är den förståelse man som fritidspolitiker har från kolleger och chefer. Här såg vi att ganska många uppgav att förståelsen för de egna kommunpolitiska åtagandena inte upplevdes vara särskilt stor bland arbetskamrater (30 procent) och närmaste chef (25 procent).

    Inte positiva till reformer av kommunpolitikens spelregler

    Under senare år har flera offentliga utredningar föreslagit en rad reformer för att stärka den lokala demokratin. I undersökningen har vi bett respondenterna ta ställning till ett par av dessa – och överlag var kritiken mot reformförslagen stor. Här fann vi exempelvis 1/ en stor skepsis till att sänka rösträttsåldern från 18 till 16 år, där nya var något mer positiva än de erfarna politikerna; 2/ att be-tydligt fler är kritiska än positiva till förslaget att krympa landets fullmäktige-församlingar; 3/ att en överväldigande majoritet av respondenterna var negativt inställda till att ersätta nuvarande system med ”samlingsregeringar” i kommun-styrelserna genom att införa majoritetsstyre, och 4/ att motståndet var starkt mot förslaget att tillåta fullmäktigeledamöter behålla sin plats fastän de flyttar från hemkommunen.

  • Public defence: 2017-05-19 13:15 K2, Kåkenhus, Norrköping
    Harling, Martin
    Linköping University, Department of Social and Welfare Studies, Learning, Aesthetics, Natural science. Linköping University, Faculty of Educational Sciences.
    Välja vara: En studie om gymnasieval, mässor och kampen om framtiden2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The thesis explores and analyzes in four empirical articles how student subjects are constructed in everyday school life and what role market principles play in these constructions. In particular, it focuses on the logics that constitute upper secondary school choice practices, and how these are legitimized, interpreted and challenged. The results show that upper secondary school choice practices divide the present and the future of the students as the choice between an explicit utopia and an implied dystopia. Here, the students themselves are made responsible for their success or failure in realizing the utopia that is staged in school choice practices. This division generally appears to the actors as natural and apolitical, which in turn legitimizes its effects in terms of exclusion, inequality and segregation, often on the basis of social class. Furthermore, the market-driven school discourses construct and divide the students as if they were commodities of different value. The notion of fantasmatic logics can explain how students are gripped by market-driven discourses and how they handle contradictory conditions. For instance, it explains how, for students, school choice means they can transform and become who they want to be, while at the same time they can also become more of what they already are, by choosing to be who they are. Students, however, problematize and destabilize dominant market logics in the school in all examined contexts, which in the thesis is analyzed in terms of penetrations and destabilizations of how schools and education are linked to the market logics. By penetrating the presupposed neutrality of secondary school choice practice, the students expose how the market orientation of education in general and the staging of school fairs in particular appear to be in schools’, rather than students’, interest.

    List of papers
    1. Examining "The Police": On Inclusion and "Investmentality" in Swedish Schooling
    Open this publication in new window or tab >>Examining "The Police": On Inclusion and "Investmentality" in Swedish Schooling
    2013 (English)In: European Education: Issues and Studies, ISSN 1056-4934, E-ISSN 1944-7086, Vol. 45, no 3, 51-66 p.Article in journal (Refereed) Published
    Abstract [en]

    In modern education, inequalities are assumed to be reduced by a redistribution of knowledge between the affluent and able on one side, and the poor and unable on the other. This article investigates ways in which the distribution of futures becomes naturalized in everyday school practices where equality is perceived as a goal rather than a starting point. The investigation draws on notions of governmentality and partition of the sensible, to analyze ethnographic material. The findings are thematized as discourses of inclusion and as "investmentality"—attitudes assumed and explained to the subjects involved.

    Place, publisher, year, edition, pages
    Taylor & Francis, 2013
    National Category
    Pedagogy International Migration and Ethnic Relations Social Sciences Interdisciplinary
    Identifiers
    urn:nbn:se:liu:diva-136516 (URN)10.2753/EUE1056-4934450304 (DOI)
    Available from: 2017-04-18 Created: 2017-04-18 Last updated: 2017-04-18Bibliographically approved
    2. Pedagogik och Postpolitik
    Open this publication in new window or tab >>Pedagogik och Postpolitik
    Show others...
    2015 (Swedish)In: Utbildning, makt och politik / [ed] Sverker Lindblad och Lisbeth Lundahl, Lund: Studentlitteratur, 2015, 195-217 p.Chapter in book (Other academic)
    Abstract [sv]

    Med vår pointillistiska ansats i form av ett antal studier får vi fram en bild av ett postpolitiskt landskap som kännetecknas av två faktorer. Den första är ett nät av aktörer – lokalt, nationellt och internationellt, exempelvis regeringen, OECD, Skolverket, McKinsey, Sveriges Kommuner och Landsting samt skolor och massmedia – som bygger på varandra i ett flöde av information och bedömningar av skolan och vad som behöver göras. Den andra är hierarkisering och konkurrens. Vad som räknas är rangordningar av länder, kommuner och skolor, vilka beskrivs genom jämförelser och har till uppgift att förbättra sina positioner eller att åtminstone inte falla nedåt. Inledningsvis pekade vi på kunskapsmätningarnas betydelse för regeringens tal om hur den svenska skolan hävdar sig, nationellt och internationellt. Den internationella konkurrensen i ekonomiskt hänseende har blivit en drivfjäder för utbildningspolitik över huvud taget (jfr Lindblad & Popkewitz, 2001; Lauder m.fl., 2006) och internationella jämförelser i form av provresultat har blivit viktiga mått på hur framgångsrikt ett land är därvidlag. Därför blir övernationella organisationer som OECD, med dess apparat för kunskapsmätningar, en viktig aktör i svensk utbildningspolitik. Och därför blir företag som McKinsey betydelsefulla, dels därför att de använder sådana mått, dels därför att de knyter dem till hur politiker och skolledare – återigen i internationellt ljus – kan hantera utbildningssystem och skolor på ett framgångsrikt sätt. Motsvarande kan sägas på nationell nivå om företag som ”Gymnasium.se”, som producerar bilder av möjliga bildningsgångar och sökmotorer för att finna vägarna dit. Vad som sker i en postpolitisk logik är att viktiga bedömningar överlåts till sådana aktörer, som befinner sig utanför skolväsendet som organisation. Och politiken kommer då också att i stor utsträckning handla om vad dessa aktörer hävdar beträffande kunskapsläge och skolorganisering. På motsvarande sätt kunde vi se hur instrument som SIRIS och SALSA, vilka tillkom för administrativa analyser, blev till verktyg för rangordning mellan kommuner och skolor. Sådana rangordningar har haft en rejäl genomslagskraft i massmedia och har använts för olika organisationers egna intressen. Jämförelser och rankingar har en inbyggd dramatik som är lättförstådd, slående och säljande. De fungerar som ett till synes objektivt underlag för kunden att informera sig om kvaliteten på skolorna som ingår i en skolmarknad i ett avreglerat och privatiserat skolväsende. Detta underlag är emellertid problematiskt då det vilar på tunna beskrivningar av skola, utbildning och kunskap vars relevans för rationellt handlande kan ifrågasättas. Detta bidrar till att talet om utbildning förändras så att fokus hamnar på jämförelser och hierarkier av olika slag i form av resultat på skolprov, betyg och positioner på rankinglistor. Utbildningspolitiska ambitioner reduceras då till att klättra på listorna eller att bibehålla positionerna. Och, som vår genomgång av massmedias rapportering visar, riktar kritiken mot makthavare in sig på dåliga listplaceringar för en skola eller ett land. Med denna logik beskrivs utbildningens mål och värde i termer av jämförelse och konkurrens. Detta gäller för såväl samhällen och utbildningssystem som skolor och elever. Vår analys av en gymnasiemässa kan belysa innebörden av postpolitiska tendenser på olika sätt. På en sådan mässa sker en översättning av skolor och elever till en ekonomi, bestående av företag som ska sälja sin vara och kunder som ska köpa varan ”utbildning” utifrån sina preferenser. Vi kan då notera hur skolorna opererar med sina varumärken och med anrop till olika kategorier av elever, för att eleverna i sin tur ska inse vilken kategori de tillhör och hur de på bästa sätt ska investera i sig själva för sin framtid. Vi kan också notera hur denna investeringslogik tycks forma elever och skolor som subjekt, som till exempel när framgångsrika elever görs till säljare av skolans varumärke (jfr Harling, 2013). Sammanfattningsvis vill vi med denna ”pointillistiska” analys peka på den bild som framträder när delarna formar en helhet. Vi menar att det är en postpolitisk bild av utbildning som växer fram, där avgörande och djupt politiska frågor om utbildningens mål och mening reducerats till teknikaliteter och till en sortering av elever byggd på ekonomisk logik. Vad vi presenterat är några nedslag och fortfarande återstår många frågor om denna omvandling att besvara.

    Place, publisher, year, edition, pages
    Lund: Studentlitteratur, 2015
    Keyword
    Utbildningspolitik, styrning, klassifikation, skoldifferentiering, post-politik, läroplansteori
    National Category
    Pedagogy Social Sciences Interdisciplinary
    Identifiers
    urn:nbn:se:liu:diva-136515 (URN)9789144076836 (ISBN)
    Available from: 2017-04-18 Created: 2017-04-18 Last updated: 2017-04-18Bibliographically approved
  • Dalgren, Evelina
    Linköping University, Department of Social and Welfare Studies.
    Skönlitteratur, teknik och naturvetenskap: en systematisk litteraturstudie om användningen av skönlitteratur i undervisningen i årskurserna F-32017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Denna systematiska litteraturstudie genomförs i syfte att undersöka vad befintlig forskning säger om användningen av skönlitteratur i undervisningen av teknik och naturvetenskap för årskurserna F-3. Frågeställningarna är enligt följande:

    - I vilken utsträckning kan, enligt tidigare forskning, skönlitteratur underlätta barns förståelse för teknik och naturvetenskap?

    - I vilken utsträckning kan, enligt tidigare forskning, skönlitteratur uppmuntra barns begreppsbildning i teknik och naturvetenskap?

    - I vilken utsträckning kan, enligt tidigare forskning, skönlitteratur bidra till att förbättra barns inställning till teknik och naturvetenskap?

    Några av de centrala begreppen i uppsatsen är begreppsbildning, teknik och teknisk allmänbildning, naturvetenskap och naturvetenskaplig allmänbildning, och skönlitterära barnböcker. Artiklarna som analyserats har främst hittats via databasen ERIC. Den litteratur det refereras till utöver artiklarna är till stor del kurslitteratur på grundlärarprogrammet F-3. Området är underbeforskat och vidare forskning anses vara befogad. Resultatet av analysen tyder på att skönlitteratur på ett bra sätt kan komplettera undervisningen av teknik och naturvetenskap, men att lärare måste vara aktiva i sitt val av de skönlitterära böcker som används. Analysen visar också att både skönlitteratur och läromedel kan innehålla förenklingar och stereotypa föreställningar som, om de får stå oemotsagda, riskerar att motverka undervisningens syfte - att grundlägga en teknisk och naturvetenskaplig allmänbildning. En saga må vara liten och oansenlig, men i kombination med rätt frågor kan den inverka på elevernas syn på teknik och naturvetenskap som i förlängningen påverkar deras framtida yrkesval.

  • Ekman, Björn
    Linköping University, Department of Electrical Engineering, Communication Systems.
    Machine Learning for Beam Based Mobility Optimization in NR2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    One option for enabling mobility between 5G nodes is to use a set of area-fixed reference beams in the downlink direction from each node. To save power these reference beams should be turned on only on demand, i.e. only if a mobile needs it. An User Equipment (UE) moving out of a beam's coverage will require a switch from one beam to another, preferably without having to turn on all possible beams to find out which one is the best.

    This thesis investigates how to transform the beam selection problem into a format suitable for machine learning and how good such solutions are compared to baseline models. The baseline models considered were beam overlap and average Reference Signal Received Power (RSRP), both building beam-to-beam maps. Emphasis in the thesis was on handovers between nodes and finding the beam with the highest RSRP. Beam-hit-rate and RSRP-difference (selected minus best) were key performance indicators and were compared for different numbers of activated beams.

    The problem was modeled as a Multiple Output Regression (MOR) problem and as a Multi-Class Classification (MCC) problem. Both problems are possible to solve with the random forest model, which was the learning model of choice during this work. An Ericsson simulator was used to simulate and collect data from a seven-site scenario with 40 UEs. Primary features available were the current serving beam index and its RSRP. Additional features, like position and distance, were suggested, though many ended up being limited either by the simulated scenario or by the cost of acquiring the feature in a real-world scenario.

    Using primary features only, learned models' performance were equal to or worse than the baseline models' performance. Adding distance improved the performance considerably, beating the baseline models, but still leaving room for more improvements.

  • Public defence: 2017-05-19 10:15 Planck, Fysikhuset, Linköping
    Melianas, Armantas
    Linköping University, Department of Physics, Chemistry and Biology, Biomolecular and Organic Electronics. Linköping University, Faculty of Science & Engineering.
    Non-Equilibrium Charge Motion in Organic Solar Cells2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Organic photovoltaic (OPV) devices based on semiconducting polymers and small molecules allow for a low cost alternative to inorganic solar cells. Recent developments show power conversion efficiencies as high as 10-12%, highlighting the potential of this technology. Nevertheless, further improvements are necessary to achieve commercialization.

    To a large extent the performance of these devices is dictated by their ability to extract the photo-generated charge, which is related to the charge carrier mobility. Various time-resolved and steady-state techniques are available to probe the charge carrier mobility in OPVs but often lead to different mobility values for one and the same system. Despite such conflicting observations it is generally assumed that charge transport in OPV devices can be described by well-defined charge carrier mobilities, typically obtained using a single steady-state technique. This thesis shows that the relevance of such well-defined mobilities for the charge separation and extraction processes is very limited.

    Although different transient techniques probe different time scales after photogeneration, they are mutually consistent as they probe the same physical mechanism governing charge motion – gradual thermalization of the photo-generated carriers in the disorder broadened density of states (DOS). The photo-generated carriers gradually lose their excess energy during transport to the extracting electrodes, but not immediately. Typically not all excess energy is dissipated as the photo-generated carriers tend to be extracted from the OPV device before reaching quasi-equilibrium.

    Carrier motion is governed by thermalization, leading to a time-dependent carrier mobility that is significantly higher than the steady-state mobility. This picture is confirmed by several transient techniques: Time-resolved Terahertz Spectroscopy (TRTS), Time-resolved Microwave Conductance (TRMC) combined with Transient Absorption (TA), electrical extraction of photo-induced charges (photo-CELIV). The connection between transient and steady-state mobility measurements (space-charge limited conductivity, SCLC) is described. Unification of transient opto-electric techniques to probe charge motion in OPVs is presented.

    Using transient experiments the distribution of extraction times of photo-generated charges in an operating OPV device has been determined and found to be strongly dispersive, spanning several decades in time. In view of the strong dispersion in extraction times the relevance of even a well-defined time-dependent mean mobility is limited.

    In OPVs a continuous ‘percolating’ donor network is often considered necessary for efficient hole extraction, whereas if the network is discontinuous, hole transport is thought to deteriorate significantly, limiting device performance. Here, it is shown that even highly diluted donor sites (5.7-10 %) in a buckminsterfullerene (C60) matrix enable reasonably efficient hole transport. Using transient measurements it is demonstrated that hole transport between isolated donor sites can occur by long-range hole tunneling (over distances of ~4 nm) through several C60 molecules – even a discontinuous donor network enables hole transport

    List of papers
    1. Unified Study of Recombination in Polymer:Fullerene Solar Cells Using Transient Absorption and Charge-Extraction Measurements
    Open this publication in new window or tab >>Unified Study of Recombination in Polymer:Fullerene Solar Cells Using Transient Absorption and Charge-Extraction Measurements
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    2013 (English)In: Journal of Physical Chemistry Letters, ISSN 1948-7185, Vol. 4, no 12, 2069-2072 p.Article in journal (Refereed) Published
    Abstract [en]

    Recombination in the well-performing bulk heterojunction solar cell blend between the conjugated polymer TQ-1 and the substituted fullerene PCBM has been investigated with pump-probe transient absorption and charge extraction of photo-generated carriers (photo-CELIV). Both methods are shown to generate identical and overlapping data under appropriate experimental conditions. The dominant type of recombination is bimolecular with a rate constant of 7 x 10(-12) cm(-3) s(-1). This recombination rate is shown to be fully consistent with solar cell performance. Deviations from an ideal bimolecular recombination process, in this material system only observable at high pump fluences, are explained with a time-dependent charge-carrier mobility, and the implications of such a behavior for device development are discussed.

    Place, publisher, year, edition, pages
    American Chemical Society, 2013
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-95964 (URN)10.1021/jz4009745 (DOI)000320979400014 ()
    Note

    Funding Agencies|Swedish Research Council||Swedish Energy Agency (STEM)||Knut and Alice Wallenberg Foundation||ERC (VISCHEM)|226136|Wallenberg Scholar grant from the Knut and Alice Wallenberg Foundation||

    Available from: 2013-08-19 Created: 2013-08-12 Last updated: 2017-04-20
    2. Dispersion-Dominated Photocurrent in Polymer:Fullerene Solar Cells
    Open this publication in new window or tab >>Dispersion-Dominated Photocurrent in Polymer:Fullerene Solar Cells
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    2014 (English)In: Advanced Functional Materials, ISSN 1616-301X, E-ISSN 1616-3028, Vol. 24, no 28, 4507-4514 p.Article in journal (Refereed) Published
    Abstract [en]

    Organic bulk heterojunction solar cells are often regarded as near-equilibrium devices, whose kinetics are set by well-defined charge carrier mobilities, and relaxation in the density of states is commonly ignored or included purely phenomenologically. Here, the motion of photocreated charges is studied experimentally with picosecond time resolution by a combination of time-resolved optical probing of electric field and photocurrent measurements, and the data are used to define parameters for kinetic Monte Carlo modelling. The results show that charge carrier motion in a prototypical polymer:fullerene solar cell under operational conditions is orders of magnitude faster than would be expected on the basis of corresponding near-equilibrium mobilities, and is extremely dispersive. There is no unique mobility. The distribution of extraction times of photocreated charges in operating organic solar cells can be experimentally determined from the charge collection transients measured under pulsed excitation. Finally, a remarkable distribution of the photocurrent over energy is found, in which the most relaxed charge carriers in fact counteract the net photocurrent.

    Place, publisher, year, edition, pages
    Weinheim, Germany: Wiley-VCH Verlagsgesellschaft, 2014
    Keyword
    solar cell; organic solar cell; dispersion; photocurrent; charge carrier relaxation; Monte Carlo simulations
    National Category
    Condensed Matter Physics
    Identifiers
    urn:nbn:se:liu:diva-108324 (URN)10.1002/adfm.201400404 (DOI)000339713900015 ()
    Note

    Funding agencies|Swedish Science Council (VR); Swedish Energy Agency; Knut and Alice Wallenberg foundation; European Social Fund under Global Grant measure

    Available from: 2014-06-26 Created: 2014-06-26 Last updated: 2017-04-20Bibliographically approved
    3. Photo-generated carriers lose energy during extraction from polymer-fullerene solar cells
    Open this publication in new window or tab >>Photo-generated carriers lose energy during extraction from polymer-fullerene solar cells
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    2015 (English)In: Nature Communications, ISSN 2041-1723, E-ISSN 2041-1723, Vol. 6, no 8778Article in journal (Refereed) Published
    Abstract [en]

    In photovoltaic devices, the photo-generated charge carriers are typically assumed to be in thermal equilibrium with the lattice. In conventional materials, this assumption is experimentally justified as carrier thermalization completes before any significant carrier transport has occurred. Here, we demonstrate by unifying time-resolved optical and electrical experiments and Monte Carlo simulations over an exceptionally wide dynamic range that in the case of organic photovoltaic devices, this assumption is invalid. As the photo-generated carriers are transported to the electrodes, a substantial amount of their energy is lost by continuous thermalization in the disorder broadened density of states. Since thermalization occurs downward in energy, carrier motion is boosted by this process, leading to a time-dependent carrier mobility as confirmed by direct experiments. We identify the time and distance scales relevant for carrier extraction and show that the photo-generated carriers are extracted from the operating device before reaching thermal equilibrium.

    Place, publisher, year, edition, pages
    Nature Publishing Group, 2015
    National Category
    Biological Sciences Physical Sciences
    Identifiers
    urn:nbn:se:liu:diva-123824 (URN)10.1038/ncomms9778 (DOI)000366294700004 ()26537357 (PubMedID)
    Note

    Funding Agencies|Swedish Science Council and Energimyndigheten; Knut and Alice Wallenberg foundation; Deutsche Forschungsgemeinschaft [SPP1355]

    Available from: 2016-01-11 Created: 2016-01-11 Last updated: 2017-04-20
    4. Photogenerated Carrier Mobility Significantly Exceeds Injected Carrier Mobility in Organic Solar Cells
    Open this publication in new window or tab >>Photogenerated Carrier Mobility Significantly Exceeds Injected Carrier Mobility in Organic Solar Cells
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    2017 (English)In: Advanced Energy Materials, ISSN 1614-6840Article in journal (Refereed) Epub ahead of print
    Abstract [en]

    Charge transport in organic photovoltaic (OPV) devices is often characterized by space-charge limited currents (SCLC). However, this technique only probes the transport of charges residing at quasi-equilibrium energies in the disorder-broadened density of states (DOS). In contrast, in an operating OPV device the photogenerated carriers are typically created at higher energies in the DOS, followed by slow thermalization. Here, by ultrafast time-resolved experiments and simulations it is shown that in disordered polymer/fullerene and polymer/polymer OPVs, the mobility of photogenerated carriers significantly exceeds that of injected carriers probed by SCLC. Time-resolved charge transport in a polymer/polymer OPV device is measured with exceptionally high (picosecond) time resolution. The essential physics that SCLC fails to capture is that of photo­generated carrier thermalization, which boosts carrier mobility. It is predicted that only for materials with a sufficiently low energetic disorder, thermalization effects on carrier transport can be neglected. For a typical device thickness of 100 nm, the limiting energetic disorder is σ ≈71 (56) meV for maximum-power point (short-circuit) conditions, depending on the error one is willing to accept. As in typical OPV materials the disorder is usually larger, the results question the validity of the SCLC method to describe operating OPVs.

    Place, publisher, year, edition, pages
    John Wiley & Sons, 2017
    Keyword
    charge carrier relaxation, charge carrier transport, organic photovoltaics, space-charge limited currents (SCLC), time-dependent mobility
    National Category
    Condensed Matter Physics Chemical Process Engineering Atom and Molecular Physics and Optics Physical Chemistry
    Identifiers
    urn:nbn:se:liu:diva-135770 (URN)10.1002/aenm.201602143 (DOI)
    Note

    1602143

    Available from: 2017-03-21 Created: 2017-03-21 Last updated: 2017-04-21Bibliographically approved
  • Tinghög, Gustav
    et al.
    Linköping University, Department of Management and Engineering, Economics. Linköping University, Department of Medical and Health Sciences, Division of Health Care Analysis. Linköping University, Faculty of Arts and Sciences. Linköping University, Faculty of Medicine and Health Sciences.
    Andersson, David
    Linköping University, Department of Management and Engineering, Economics. Linköping University, Faculty of Arts and Sciences.
    Västfjäll, Daniel
    Linköping University, Department of Management and Engineering, Economics. Linköping University, Faculty of Arts and Sciences. Decision Research, Eugene, OR, USA.
    Are Individuals Luck Egalitarians? – An experiment on the influence of brute and option luck on social preferences2017In: Frontiers in Psychology, ISSN 1664-1078, E-ISSN 1664-1078, Vol. 8, 460Article in journal (Refereed)
    Abstract [en]

    According to luck egalitarianism, inequalities should be deemed fair as long as they follow from individuals’ deliberate and fully informed choices (i.e., option luck) while inequalities should be deemed unfair if they follow from choices over which the individual has no control (i.e., brute luck). This study investigates if individuals’ fairness preferences correspond with the luck egalitarian fairness position. More specifically, in a laboratory experiment we test how individuals choose to redistribute gains and losses that stem from option luck compared to brute luck. A two-stage experimental design with real incentives was employed. We show that individuals (n = 226) change their action associated with re-allocation depending on the underlying conception of luck. Subjects in the brute luck treatment equalized outcomes to larger extent (p = 0.0069). Thus, subjects redistributed a larger amount to unlucky losers and a smaller amount to lucky winners compared to equivalent choices made in the option luck treatment. The effect is less pronounced when conducting the experiment with third-party dictators, indicating that there is some self-serving bias at play. We conclude that people have fairness preference not just for outcomes, but also for how those outcomes are reached. Our findings are potentially important for understanding the role citizens assign individual responsibility for life outcomes, i.e., health and wealth. 

  • Östman, Nicklas
    et al.
    Linköping University, Department of Computer and Information Science, Software and Systems.
    Lindström, Rasmus
    Linköping University, Department of Computer and Information Science, Software and Systems.
    Vertically Scaling Agile: A Multiple-Case Study2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The conceptual framework of agile software development is an ever-growing movement in the software industry. However, recent studies have shown that large, less software-focused companies, where software development is primarily used for in-house IT-solutions, struggle with giving up traditional command-control type of management. This hits hard on some of the most important principles of agile software development and in many cases this phenomenon has inevitably led to large gaps between development teams and more managerial parts of the organization. This thesis has aimed to study this gap and investigate how it affects software development teams’ ability to carry out their work.

    By comparing three software teams that were internally highly similar but with varying external conditions, impact on the teams’ behaviour based on their different environments was studied. The study was carried out using a multiple-case study approach with primary data sources consisting of survey gathered data from all team members and interviews with a subset of the team members. The results gathered from this study suggest that agile development teams are extremely dependent on a well-functioning interface to business related parts of an organization. Regarding teams’ ability to make decisions and being agile in their way of working, the results primarily isolate impediments with roots in an unwillingness to adhere to and lack of understanding of agile principles.

    In this thesis, our gathered results were also correlated with a modern framework called Flow in order to confirm its relevance regarding analyzing software development teams in large-scale environments. 

  • Han, Dapeng
    Linköping University, Department of Electrical Engineering, Computer Engineering.
    FPGA Implementation of an AC3 Decoder2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The aim of this thesis is to explore the possibility of integrating an AC3 audio de- coding module into the company’s current product. Due to limited left resources on the FPGA chip in the company’s current product, the focus of this thesis is to be resource efficient. In this thesis, a system for AC3 audio decoding is designed and implemented. In order to use less logic on FPGA, PicoBlaze soft processor is used to control the whole processing flow. The system is designed and synthe- sized for a Spartan-6 FPGA which can be easily ported to the company’s current platform. 

  • Nöjdh, Oscar
    Linköping University, Department of Computer and Information Science, Software and Systems.
    Intelligent boundary extraction for area and volume measurement: Using LiveWire for 2D and 3D contour extraction in medical imaging2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis tries to answer if a semi-automatic tool can speed up the process of segmenting tumors to find the area of a slice in the tumor or the volume of the entire tumor. A few different 2D semi-automatic tools were considered. The final choice was to implement live-wire. The implemented live-wire was evaluated and improved upon with hands-on testing from developers. Two methods were found for extending live-wire to 3D bodies. The first method was to interpolate the seed points and create new contours using the new seed points. The second method was to let the user segment contours in two orthogonal projections. The intersections between those contours and planes in the third orthogonal projection were then used to create automatic contours in this third projection. Both tools were implemented and evaluated. The evaluation compared the two tools to manual segmentation on two cases posing different difficulties. Time-on-task and accuracy were measured during the evaluation. The evaluation revealed that the semi-automatic tools could indeed save the user time while maintaining acceptable (80%) accuracy. The significance of all results were analyzed using two-tailed t-tests.

  • Engström, Julia
    Linköping University, Department of Management and Engineering, Political Science.
    Digital delaktighet och projektet Digital mediebuss i Östergötland: En studie om politisk styrning, demokrati och delaktighet2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis examines digital inclusion and how it is governed in today’s politics. The main focus is on the region of Östergötland, the municipality of Norrköping and a project called Digital media bus in Östergötland. To give the reader some understanding about digital inclusion the thesis starts with earlier research on digital inclusion, the role of the library in solving this problem about digital divides and how it has been governed before. Then, some background information about Europe and Swedens digital development, their digital agendas, current legislation in Sweden about digital inclusion and two campaign weeks which aim to increase the digital inclusion in Europe and Sweden. The theoretical framework is based on a theory about different policy instruments and from a governance perspective. The theoretical framework interacts with the empirical material in the analysis. The empirical material is based on interviews with two politicians and three public officials, on different regulatory documents and on the project Digital media bus in Östergötland which has been observed during the year of 2016. The empirical material is presented in the sixth chapter called ”There are needs, so there must be solutions!”.

    The result is that digital inclusion is a policy which is hard to govern. Today, it seems like there is mostly soft policy instruments and the way to govern is from a governance perspective – which means that there are a lot of networks and dissemination of information. However, a harder way to govern is requested by the informants because it may release necessary resources to solve the problem with digital exclusion. The project Digital media bus in Östergötland used mostly soft policy instruments in their work with getting children more technical skilled and digital curious. The main outcome from the project is that the problem with digital inclusion has got more attention both in the politics and the official administration, but the project has also shown the importance of cooperation. Lastly in my thesis, I discuss my results and propose some further research about digital inclusion. 

  • Public defence: 2017-04-28 10:15 Planck, Fysikhuset, Linköping
    Mosyagin, Igor
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Physics. Linköping University, Faculty of Science & Engineering.
    Development and applications of theoretical algorithms for simulations of materials at extreme conditions2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Materials at extreme conditions exhibit properties that differ substantially from ambient conditions. High pressure and high temperature expose anharmonic, non-linear behavior, and can provoke phase transitions among other effects. Experimental setups to study that sort of effects are typically costly and experiments themselves are laborious. It is common to apply theoretical techniques in order to provide a road-map for experimental research. In this thesis I cover computational algorithms based on first-principles calculations for high-temperature and high-pressure conditions. The two thoroughly described algorithms are: 1) the free energy studies using temperature-dependent effective potential method (TDEP), and 2) a higher-order elastic constants calculation procedure. The algorithms are described in an easy to follow manner with motivation for every step covered.

    The Free energy calculation algorithm is demonstrated with applications to hexagonal close-packed Iron at the conditions close to the inner Earth Core’s. The algorithm of elastic constants calculation is demonstrated with application to Molybdenum, Tantalum, and Niobium. Other projects included in the thesis are the study of effects of van der Waals corrections on the graphite and diamond equations of state.

    List of papers
    1. Highly Efficient Free Energy Calculations of the Fe Equation of State Using Temperature-Dependent Effective Potential Method
    Open this publication in new window or tab >>Highly Efficient Free Energy Calculations of the Fe Equation of State Using Temperature-Dependent Effective Potential Method
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    2016 (English)In: Journal of Physical Chemistry A, ISSN 1089-5639, E-ISSN 1520-5215, Vol. 120, no 43, 8761-8768 p.Article in journal (Refereed) Published
    Abstract [en]

    Free energy calculations at finite temperature based on ab initio molecular dynamics (AIMD) simulations have become possible, but they are still highly computationally demanding. Besides, achieving simultaneously high accuracy of the calculated results and efficiency of the computational algorithm is still a challenge. In this work we describe an efficient algorithm to determine accurate free energies of solids in simulations using the recently proposed temperature-dependent effective potential method (TDEP). We provide a detailed analysis of numerical approximations employed in the TDEP algorithm. We show that for a model system considered in this work, hcp Fe, the obtained thermal equation of state at 2000 K is in excellent agreement with the results of standard calculations within the quasiharmonic approximation.

    Place, publisher, year, edition, pages
    American Chemical Society (ACS), 2016
    National Category
    Theoretical Chemistry
    Identifiers
    urn:nbn:se:liu:diva-132993 (URN)10.1021/acs.jpca.6b08633 (DOI)000387198600028 ()27700093 (PubMedID)
    Note

    Funding Agencies|Swedish Foundation for Strategic Research (SSF) program SRL [10-0026]; Swedish Research Council (VR) [2015-04391, 2014-4750, 637-2013-7296]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009 00971]; Ministry of Education and Science of the Russian Federation [14.Y26.31.0005]; PRACE-2IP project [FP7 RI-283493]

    Available from: 2016-12-09 Created: 2016-12-07 Last updated: 2017-04-24Bibliographically approved
    2. Theoretical description of pressure-induced phase transitions: a case study of Ti-V alloys
    Open this publication in new window or tab >>Theoretical description of pressure-induced phase transitions: a case study of Ti-V alloys
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    2015 (English)In: High Pressure Research, ISSN 0895-7959, Vol. 35, no 1, 42-48 p.Article in journal (Refereed) Published
    Abstract [en]

    We discuss theoretical description of pressure-induced phase transitions by means of first-principles calculations in the framework of density functional theory. We illustrate applications of theoretical tools that allow one to take into account configurational and vibrational disorders, considering Ti-V alloys as a model system. The universality of the first-principles theory allows us to apply it in studies of different phenomena that occur in the Ti-V system upon compression. Besides the transitions between different crystal structures, we discuss isostructural transitions in bcc Ti-V alloys. Moreover, we present arguments for possible electronic transitions in this system, which may explain peculiar behaviour of elastic properties of V upon compression.

    Place, publisher, year, edition, pages
    Taylor andamp; Francis: STM, Behavioural Science and Public Health Titles, 2015
    Keyword
    phase stability; first-principles calculations; Ti-V alloys; high pressure
    National Category
    Physical Sciences
    Identifiers
    urn:nbn:se:liu:diva-114586 (URN)10.1080/08957959.2014.992896 (DOI)000348672100007 ()
    Note

    Funding Agencies|Ministry of Education and Science of the Russian Federation [14.Y26.31.0005]; SSF [SRL 10-0026]; Russian Foundation for Basic Researches [13-02-00606a]; Tomsk State University Academic D.I. Mendeleev Fund Program; Program of Fundamental Research of State Academies of Sciences

    Available from: 2015-02-27 Created: 2015-02-26 Last updated: 2017-04-10
    3. Finite Temperature, Magnetic, and Many-Body Effects in Ab Initio Simulations of Alloy Thermodynamics
    Open this publication in new window or tab >>Finite Temperature, Magnetic, and Many-Body Effects in Ab Initio Simulations of Alloy Thermodynamics
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    2013 (English)In: TMS2013 Supplemental Proceedings, John Wiley & Sons, 2013, 617-626 p.Chapter in book (Refereed)
    Abstract [en]

    Ab initio electronic structure theory is known as a useful tool for prediction of materials properties. However, majority of simulations still deal with calculations in the framework of density functional theory with local or semi-local functionals carried out at zero temperature. We present new methodological solution.s, which go beyond this approach and explicitly take finite temperature, magnetic, and many-body effects into account. Considering Ti-based alloys, we discuss !imitations of the quasiharmonic approximation for the treatment of lattice vibrations, and present an accurate and easily extendable method to calculate free ,energies of strongly anharmonic solids. We underline the necessity to going beyond the state-of-the-art techniques for the determination of effective cluster interactions in systems exhibiting mctal-to-insulator transition, and describe a unified cluster expansion approach developed for this class of materials. Finally, we outline a first-principles method, disordered local moments molecular dynamics, for calculations of thermodynamic properties of magnetic alloys, like Cr1-x,.AlxN, in their high-temperature paramagnetic state. Our results unambiguously demonstrate importance of finite temperature effects in theoretical calculations ofthermodynamic properties ofmaterials.

    Place, publisher, year, edition, pages
    John Wiley & Sons, 2013
    Keyword
    Alloy thermodynamics, Ti alloys, (Ti-Al)N, (Cr-Al)N
    National Category
    Condensed Matter Physics Theoretical Chemistry Inorganic Chemistry Metallurgy and Metallic Materials
    Identifiers
    urn:nbn:se:liu:diva-136443 (URN)10.1002/9781118663547.ch77 (DOI)9781118605813 (ISBN)9781118663547 (ISBN)
    Available from: 2017-04-10 Created: 2017-04-10 Last updated: 2017-04-21Bibliographically approved
  • Angelhoff, Charlotte
    Linköping University, Department of Social and Welfare Studies, Division of Nursing Science. Linköping University, Faculty of Medicine and Health Sciences.
    What about the parents?: Sleep quality, mood, saliva cortisol response and sense of coherence in parents with a child admitted to pediatric care2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Parents experience many stressful situations when their child is ill and needs medical care, irrespective of the child’s age, diagnosis or the severity of the illness. Poor sleep quality and negative mood decrease the parents’ ability to sustain attention and focus, to care for their ill child, and to cope with the challenges they face.

    The overall aim of this thesis was to evaluate sleep, mood, cortisol response, and sense of coherence (SOC) in parents caring for children in need of medical care, and to identify factors that may influence parents’ sleep.

    This thesis includes four original studies; two of these are quantitative, prospective, descriptive and comparative studies including parents (n=82) accommodated in six pediatric wards with their ill child, using questionnaires and sleep logs to measure sleep, mood and SOC, and saliva cortisol to measure cortisol response. A follow-up was performed four weeks later at home, after hospital discharge. The other two studies are qualitative, inductive and explorative interview studies, including parents (n=12) staying overnight with their preterm and/or ill infant in three neonatal intensive care units, and parents (n=15) with a child receiving hospital-based home care in two pediatric outpatient clinics. The interviews were analyzed with a phenomenographic method.

    Being together with one’s family seems beneficial for sleep and may decrease stress. The ability to stay with the child, in the hospital or at home, was highly appreciated by the parents. When caring for a child with illness, parents’ sleep quality was sufficient in the hospital; however, sleep quality improved further (p<0.05) at home after discharge. The parents reported frequent nocturnal awakenings in the hospital caused by the child, medical treatment and hospital staff. Concern and anxiety about the child’s health, and uncertainty about the future were stressors affecting the parents’ sleep and mood negatively. The parents had lower (p=0.01) morning awakening cortisol levels in the pediatric ward compared to at home, and parents accommodated for more than one night had lower (p<0.05) post-awakening cortisol levels compared to parents staying their first night.

    The findings of this thesis conclude that being together as a family is important for the parents’ sleep. The ability to be accommodated in the hospital and gather the family around the child may have given the parents time for relaxation and recovery, that in turn may lead to a less stressful hospital stay. When it is beneficial for the child, the whole family should be included in the pediatric care. Moreover, pediatric nurses must acknowledge parents’ sleep, in hospital and at home. Medical treatment and care at night should be scheduled and sleep promoted for the parents in order to maintain health and well-being in the family.

    List of papers
    1. Hindering and buffering factors for parental sleep in neonatal care. A phenomenographic study
    Open this publication in new window or tab >>Hindering and buffering factors for parental sleep in neonatal care. A phenomenographic study
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    2015 (English)In: Journal of Clinical Nursing, ISSN 0962-1067, E-ISSN 1365-2702, Vol. 24, no 5-6, 717-727 p.Article in journal (Refereed) Published
    Abstract [en]

    AIMS AND OBJECTIVES:

    To explore and describe how parents of preterm and/or sick infants in neonatal care perceive their sleep.

    BACKGROUND:

    Parents experience many stressful situations when their newborn infant is preterm and/or sick. This affects bonding. By developing more family-centred care units with single-family rooms, parents are given the opportunity to stay and care for their newborn infant(s) 24 hours a day. Lack of sleep may affect new parents' ability to cope with the many challenges they face on a daily basis.

    DESIGN:

    A phenomenographic study with an inductive and exploratory design.

    METHODS:

    Semi-structured interviews were conducted with twelve parents of infants in neonatal care between January-March 2012. To describe variations in perception of the phenomenon, data were analysed using phenomenography.

    FINDINGS:

    Four descriptive categories were identified within the phenomenon sleep in parents of preterm and/or sick infants in neonatal care: impact of stress on sleep; how the environment affects sleep; keeping the family together improves sleep; and, how parents manage and prevent tiredness.

    CONCLUSION:

    Anxiety, uncertainty and powerlessness have a negative influence on sleep. This can be decreased by continuous information, guidance and practical support. Skin-to-skin care was perceived as a stress-reducing factor that improved relaxation and sleep and should be encouraged by the nurse. The parents also mentioned the importance of being together. Having a private place where they could relax and take care of themselves and their newborn infant improved sleep. It was also desirable to involve older siblings in order to decrease feelings of loneliness, sadness and isolation.

    RELEVANCE FOR CLINICAL PRACTICE:

    Improved parental sleep in neonatal care may help the families cope with the situation and facilitate problem-solving, emotional regulation and the transition to parenthood.

    Place, publisher, year, edition, pages
    John Wiley & Sons, 2015
    Keyword
    family nursing; family-centred care; kangaroo mother care; neonatal intensive care; nursing; siblings; skin-to-skin care
    National Category
    Nursing
    Identifiers
    urn:nbn:se:liu:diva-115549 (URN)10.1111/jocn.12654 (DOI)000350354700010 ()25041598 (PubMedID)
    Funder
    Medical Research Council of Southeast Sweden (FORSS)Östergötland County Council
    Available from: 2015-03-16 Created: 2015-03-16 Last updated: 2017-04-10
    2. Sleep of Parents Living With a Child Receiving Hospital-Based Home Care: A Phenomenographical Study.
    Open this publication in new window or tab >>Sleep of Parents Living With a Child Receiving Hospital-Based Home Care: A Phenomenographical Study.
    2015 (English)In: Nursing Research, ISSN 0029-6562, E-ISSN 1538-9847, Vol. 64, no 5, 372-380 p.Article in journal (Refereed) Published
    Abstract [en]

    Background: Caring for an ill child at home gives the family the chance to be together in a familiar environment. However, this involves several nocturnal sleep disturbances, such as frequent awakenings and bad sleep quality, which may affect parents' ability to take care of the child and themselves.

    Objectives: The aim of this study was to describe parents' perceptions of circumstances influencing their own sleep when living with a child enrolled in hospital-based home care (HBHC) services.

    Method: This is a phenomenographical study with an inductive, exploratory design. Fifteen parents (11 mothers and 4 fathers) with children enrolled in HBHC services were interviewed. Data were analyzed to discover content-related categories describing differences in ways parents experienced sleep when caring for their children receiving HBHC.

    Results: Four descriptive categories were detected: sleep influences mood and mood influences sleep; support influences safeness and safeness influences sleep; the child's needs influence routines and routines influence sleep; and "me time" influences sleep.

    Discussion: Sleep does not affect only the parents' well-being but also the child's care. Symptoms of stress may limit the parents' capacity to meet the child's needs. Support, me time, and physical activity were perceived as essential sources for recovery and sleep. It is important for nurses to acknowledge parental sleep in the child's nursing care plan and help the parents perform self-care to promote sleep and maintain life, health, and well-being.

    Place, publisher, year, edition, pages
    Lippincott-Ravn Publisher, 2015
    Keyword
    children, chronic illness, home care services, parents, qualitative research, sleep
    National Category
    Nursing
    Identifiers
    urn:nbn:se:liu:diva-121085 (URN)10.1097/NNR.0000000000000108 (DOI)000361361000006 ()26325279 (PubMedID)
    Projects
    Parents’ stress and sleep quality when their children need medical care
    Funder
    Östergötland County CouncilMedical Research Council of Southeast Sweden (FORSS)
    Available from: 2015-09-07 Created: 2015-09-07 Last updated: 2017-04-10Bibliographically approved
  • Ipsonius, Birgitta
    Linköping University, Department of Behavioural Sciences and Learning.
    Att skapa plats för barns lek i förskolans utomhusmiljö2017Independent thesis Advanced level (degree of Master (Two Years)), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Den här studien är ett kunskapsbidrag avseende barns användning av förskolors utomhusmiljö samt barns inkludering i utveckling av förskolegårdars lekmiljö. Studiens syfte är att tolka samt skapa förståelse för de deltagande förskolebarnens subjektiva upplevelse av sin förskolegård. Studiens forskningsfrågor behandlar vilka slags lekar barnen ägnar sig åt i de utvalda lekmiljöerna, vad som möjliggör barnens lek samt vilka hinder som finns för barnens lek.

    Studiens teoretiska utgångspunkter är handlingserbjudanden. Genom pedagogernas handlingserbjudanden till förskolebarnen kan lekmiljön och därmed barnens fysiska rörelsemönster påverkas. Vidare kan handlingserbjudanden gällande ett föränderligt och mobilt lekmaterial vidareutveckla gestaltningsleken. Jag har valt att använda mig av gåtursmetoden som datainsamlingsmetod samt Grundad teori (Grounded Theory) som analysmetod.

    Utifrån förskolans uppdrag att utgå från barnens behov och intresse bör förskolan ta del av samt vidareutveckla barnens tankar kring förskolegårdens utformning. För att inspirera och leda pedagogerna framåt i detta arbete vill jag genom min studie påvisa arbetsredskap som kan användas i arbetet med att utforma platser på förskolegården som intresserar barnen och stimulerar deras lek. Studiens resultat visar att påverkansfaktorer på barnens lek är lekmiljöns utformning, tillgängligt lekmaterial samt förhållningsregler. Analysen visar att genom pedagogers handlingserbjudanden samt en tillåtande, stimulerande samt utmanande lekmiljö kan barnen få natur- samt lekupplevelser och utveckla sina fysiska färdigheter. Studiens slutsats belyser att arbetsredskap såsom pedagogisk dokumentation, reflekterande samtal, observationer samt samtal med barnen kan vara passande för att göra barnen delaktiga i utformningen av förskolans utomhusmiljö.

  • Jidesjö, Anders
    et al.
    Linköping University, Department of Thematic Studies, Tema Environmental Change. Linköping University, Faculty of Arts and Sciences.
    Uhrqvist, Ola
    Linköping University, Department of Thematic Studies. Folkungaskolan, Linköpings kommun, Linköping.
    Vår stad 2030 och efterföljande rådslag: Om kapacitet för utbildning och delaktighet2016Report (Other academic)
    Abstract [en]

    This report is the result of an external assessment based on qualitative interviews with 5 city planners, 9 teachers and 22 pupils participating in the project in 2015 and 2016.

    The empirical evidence indicate an appreciated project where city planners highlight the ability to reach out to young city dwellers, usually a difficult group to engage in city planning; teachers that stress the projects concrete but at the same time flexible design as a valuable resource in their present and future work; least but not last the pupils talk about the project as something that was real which in turn spurred their commitment to reach for quality in their work. At the end of the project these pupils expressed increased knowledge and engagement in sustainable development. Especially the social dimensions and the local perspective were seen as fresh and inspiring. At the same time teachers highlighted the solid frame of the project giving them more time to cooperate with each other and attend to supervise the pupils along the way.

    The assessment also finds that the different time-scales that guide the practices of city planners’, teachers’ and pupils’ pose a challenge for cooperation between the groups, as they work together for the first time. Here teachers has to become brokers between the longer time-horizons of the city planners and the much shorter time-horizon providing meaning to the pupils. Another obstacle is the institutional structures of the education system. Firstly it concerns the information infrastructure. The interviews show that the invitation reached teachers via informal channels and thus only reached teachers that was already known to be engaged in education for sustainable development. Secondly, and especially at the Gymnasium level, the organisation around courses prevented interdisciplinary approaches to education for sustainable development.

    Looking ahead the assessment finds a consensus among the participants that it has been a valuable experience. That all participating city planners and teachers seek for ways to repeat the project in one way or the other might be the best evidence for the projects quality. The results presented in this report are shortly framed and discussed in relation with some scientific studies concerned with learning, relevance and function of education and connections between education and societal development. The discussions points out the importance of social inclusion, personal fulfilment and education for all as capacities for urban planning and transformative approaches in societal and educational development.

    As the project moves on to new cities the assessment points to a few possible options for development. It could be valuable to develop strategies for reaching a broader range of teachers, ways to improve administrative support within the institutional structures of the participating schools. Thirdly, one way to strengthen the connection between the pupils increased interest and broader socio-political discussion could be to invite political and non-governmental organisations to participate either at the Rådslag* or in the preparations for it. This might be valuable since the engagement in sustainability issues has mainly been channelled into action at the individual level, mainly to consumption. Many participants have also asked for support for upcoming versions of Vår stad 2030. Developing support for the difficult step that would take Vår stad 2030 from an event to a part of the ordinary practices could perhaps be a valuable step to take in further development.

  • Hallgren, Jenny
    et al.
    Linköping University, Department of Social and Welfare Studies.
    Tjäder Millestad, Julia
    Linköping University, Department of Social and Welfare Studies.
    Barn som väcker funderingar: En intervjustudie om förskollärares resonemang gällande barn i behov av särskilt stöd2017Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
  • Costa, Antonio F.
    et al.
    Departamento de Matematicas Fundamentales, UNED.
    Izquierdo, Milagros
    Linköping University, Department of Mathematics, Mathematics and Applied Mathematics. Linköping University, Faculty of Science & Engineering.
    Porto, Ana M.
    Departamento de Matematicas Fundamentales, UNED.
    On the connectedness of the branch locus of moduli space of hyperelliptic Klein surfaces with one boundary2017In: International Journal of Mathematics, ISSN 0129-167X, ISSN ISSN 0129-167XArticle in journal (Refereed)
  • Aghighi, Meysam
    et al.
    Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering.
    Bäckström, Christer
    Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering.
    Plan Reordering and Parallel Execution -- A Parameterized Complexity View2017Conference paper (Refereed)
    Abstract [en]

    Bäckström has previously studied a number of optimization problems for partial-order plans, like finding a minimum deordering (MCD) or reordering (MCR), and finding the minimum parallel execution length (PPL), which are all NP-complete. We revisit these problems, but applying parameterized complexity analysis rather than standard complexity analysis. We consider various parameters, including both the original and desired size of the plan order, as well as its width and height. Our findings include that MCD and MCR are W[2]-hard and in W[P] when parameterized with the desired order size, and MCD is fixed-parameter tractable (fpt) when parameterized with the original order size. Problem PPL is fpt if parameterized with the size of the non-concurrency relation, but para-NP-hard in most other cases. We also consider this problem when the number (k) of agents, or processors, is restricted, finding that this number is a crucial parameter; this problem is fixed-parameter tractable with the order size, the parallel execution length and k as parameter, but para-NP-hard without k as parameter.

  • Abdelrahman, Islam
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Hand and Plastic Surgery. Plastic Surgery Unit, Surgery Department, Suez Canal University, Ismailia, Egypt.
    Elmasry, Moustafa
    Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Hand and Plastic Surgery. Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Plastic Surgery Unit, Surgery Department, Suez Canal University, Ismailia, Egypt.;.
    Olofsson, Pia
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Hand and Plastic Surgery.
    Steinvall, Ingrid
    Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Hand and Plastic Surgery. Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Medicine and Health Sciences.
    Fredrikson, Mats
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences.
    Sjöberg, Folke
    Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Hand and Plastic Surgery. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Anaesthesiology and Intensive Care in Linköping. Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology.
    Division of overall duration of stay into operative stay and postoperative stay improves the overall estimate as a measure of quality of outcome in burn care.2017In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 12, no 3, e0174579Article in journal (Refereed)
    Abstract [en]

    Patients and Methods: Surgically managed burn patients admitted between 2010-14 were included. Operative stay was defined as the time from admission until the last operation, postoperative stay as the time from the last operation until discharge. The difference in variation was analysed with F-test. A retrospective review of medical records was done to explore reasons for extended postoperative stay. Multivariable regression was used to assess factors associated with operative stay and postoperative stay.less thanbr /greater thanResults: Operative stay/TBSA% showed less variation than total duration/TBSA% (F test = 2.38, pless than0.01). The size of the burn, and the number of operations, were the independent factors that influenced operative stay (R2 0.65). Except for the size of the burn other factors were associated with duration of postoperative stay: wound related, psychological and other medical causes, advanced medical support, and accommodation arrangements before discharge, of which the two last were the most important with an increase of (mean) 12 and 17 days (pless than0.001, R2 0.51).less thanbr /greater thanConclusion: Adjusted operative stay showed less variation than total hospital stay and thus can be considered a more accurate outcome measure for surgically managed burns. The size of burn and number of operations are the factors affecting this outcome measure.

  • Äng, Oscar
    et al.
    Linköping University, Department of Mathematics. Linköping University, Faculty of Science & Engineering.
    Trygg, Alexander
    Linköping University, Department of Mathematics. Linköping University, Faculty of Science & Engineering.
    Planering av stränggjutningsproduktion: En heruistisk metod2017Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    This study aims to investigate if it is possible to use a heuristic method to create feasible solution in a Cast Batching Problem at SSAB. The problem occurs when different kinds of steel should be cast during the same day. Depending on which order the groups of different steel is placed different amounts of waste is produced, the goal is to minimize this waste. Earlier work has been done on this problem and resulted in a mathematical model to create feasible solutions to this problem. In practice the time it takes to create good solutions are long and the question is if it is possible to use a heuristic method to generate good solutions in a shorter amount of time.

    Drawing upon inspiration from metaheuristics such as Variable Neighbourhood Search, Simualted Annealing and Tabu Search multiple heuristics have been created, implemented and evaluated against the mathematical model. One of the heuristics perform better than the mathematical model does in 10 minutes. The result from the mathematical model after 60 minutes is slightly better than the heuristic, but the results are similar. With regards to running time the heuristic takes considerably less time than 10 minutes.

  • Scott, Anna Mae
    et al.
    Centre for Research in Evidence-Based Practice (CREBP), Bond University, Gold Coast, Queensland, Australia.
    Hofmann, Björn
    Norwegian University for Science and Technology, Gjøvik, Norway; University of Oslo, Oslo, Norway.
    Gutiérrez-Ibarluzea, Iñaki
    Nursing University School Vitoria-Gasteiz, Vitoria-Gasteiz, Basque Country, Spain; Research and Innovation Directorate, Department for Health, Vitoria-Gasteiz, Basque Country, Spain .
    Bakke Lysdahl, Kristin
    University of Oslo, Oslo, Norway.
    Sandman, Lars
    Linköping University, Department of Medical and Health Sciences, Division of Health Care Analysis. Linköping University, Faculty of Medicine and Health Sciences. University of Borås, Borås, Sweden.
    Bombard, Yvonne
    St. Michael's Hospital, Toronto, Canada; University of Toronto, Toronto, Canada.
    Q-SEA – a tool for quality assessment of ethics analyses conducted as part of health technology assessments2017In: GMS Health Technology Assessment, ISSN 1861-8863, E-ISSN 1861-8863, Vol. 13Article in journal (Refereed)
    Abstract [en]

    Introduction: Assessment of ethics issues is an important part of health technology assessments (HTA). However, in terms of existence of quality assessment tools, ethics for HTA is methodologically under-developed in comparison to other areas of HTA, such as clinical or cost effectiveness.Objective: To methodologically advance ethics for HTA by: (1) proposing and elaborating Q-SEA, the first instrument for quality assessment of ethics analyses, and (2) applying Q-SEA to a sample systematic review of ethics for HTA, in order to illustrate and facilitate its use. Methods: To develop a list of items for the Q-SEA instrument, we sys-tematically reviewed the literature on methodology in ethics for HTA, reviewed HTA organizations’ websites, and solicited views from 32 ex-perts in the field of ethics for HTA at two 2-day workshops. We sub-sequently refined Q-SEA through its application to an ethics analysis conducted for HTA.Results: Q-SEA instrument consists of two domains – the process do-main and the output domain. The process domain consists of 5 ele-ments: research question, literature search, inclusion/exclusion criteria, perspective, and ethics framework. The output domain consists of 5 elements: completeness, bias, implications, conceptual clarification, and conflicting values.Conclusion: Q-SEA is the first instrument for quality assessment of ethics analyses in HTA. Further refinements to the instrument to enhance its usability continue.

  • Pihl, Torbjörn
    Linköping University, Department of Behavioural Sciences and Learning.
    Arbetet med ungdomar som utmanar i naturbruksskolor2017Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This is a paper based on a selection of agriculture schools and their work with students that challenge school culture and the responsible of their education on many levels. The survey is based on a qualitative method, where the collection of data relies on focus groups and observatory studies. The study shows that the schools in focus had a similar attitude as well as practice concerning these students. The schools are using multi modal and multi professional ways in their practice towards students with challenging behavior. The study also shows the importance of searching for the solutions that work instead of focusing on what is wrong, that is, that we treat students different only if needed. When we feel that our method doesn´t work and the student needs more support than their fellow students, we must do something about it. The study shows that we in the world of school, must initially take the individual in consideration and secondly he / her diagnose or etiquette. The diagnose or etiquette of the students should be seen more like a help in understanding how to adapt the education and not automatically present the diagnose as a program or adaptation with an already done structure for the student. To find relationships creating processes of positive educational environments is also an obvious result in the study.

  • Juska, Arunas
    et al.
    East Carolina University, NC 27858 USA.
    Woolfson, Charles
    Linköping University, Department of Social and Welfare Studies, REMESO - Institute for Research on Migration, Ethnicity and Society. Linköping University, Faculty of Arts and Sciences.
    The lmoral discourses of post-crisis neoliberalism: a case study of Lithuanias Labour Code reform2017In: Critical Discourse Studies, ISSN 1740-5904, E-ISSN 1740-5912, Vol. 14, no 2, 132-149 p.Article in journal (Refereed)
    Abstract [en]

    This article problematizes the neoliberal reconfiguration of labour rights in Lithuania, a newer European Union member state, in which the impacts of the global economic and financial crisis were particularly severe and where radical austerity measures were subsequently imposed. Now, after six years, in an attempt to resolve the exhaustion of previous austerity-based solutions for economic recovery, a new Labour Code is being introduced which will further weaken labour protections and labour rights. This article analyses conflicting positions in current debates over Labour Code reform. It attempts to map the mobilization of strategic discursive resources in an unfolding dialogical moral politics of Labour Code reform in the current conjuncture of postcrisis. Theoretically, this article draws upon the seminal work of the early Soviet Marxist scholar V. N. Voloshinov in proposing a dialogical method which foregrounds the interconnections of language, class and ideology.

  • Garrido Gálvez, Mario
    et al.
    Linköping University, Department of Electrical Engineering, Computer Engineering. Linköping University, Faculty of Science & Engineering.
    Angel Sanchez, Miguel
    University of Politecn Madrid, Spain.
    Luisa Lopez-Vallejo, Maria
    University of Politecn Madrid, Spain.
    Grajal, Jesus
    University of Politecn Madrid, Spain.
    A 4096-Point Radix-4 Memory-Based FFT Using DSP Slices2017In: IEEE Transactions on Very Large Scale Integration (vlsi) Systems, ISSN 1063-8210, E-ISSN 1557-9999, Vol. 25, no 1, 375-379 p.Article in journal (Refereed)
    Abstract [en]

    This brief presents a novel 4096-point radix-4 memory-based fast Fourier transform (FFT). The proposed architecture follows a conflict-free strategy that only requires a total memory of size N and a few additional multiplexers. The control is also simple, as it is generated directly from the bits of a counter. Apart from the low complexity, the FFT has been implemented on a Virtex-5 field programmable gate array (FPGA) using DSP slices. The goal has been to reduce the use of distributed logic, which is scarce in the target FPGA. With this purpose, most of the hardware has been implemented in DSP48E. As a result, the proposed FPGA is efficient in terms of hardware resources, as is shown by the experimental results.

  • Matulu, Reagan
    Linköping University, Department of Social and Welfare Studies.
    En kvalitativ studie om samverka för ensamkommande flyktingbarns integrationsprocess2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Uppsatsen bygger på en kvalitativ studie av utforskade möjligheter och hinder i samverkansprocessen av att arbeta med ensamkommande barn och ungdomar. Det som framkom som det viktigaste i samverkansprocessen var ökad kunskap om målgruppen. När det gäller processer, brist på vägledning och brist på kunskap sågs som hinder i samarbetet. Det som kan bidra till en positiv utveckling är tydligare ansvar och roller för socialarbetare, skolpersonal och personal vid HVB (hem för vård och boende). Återkommande problem var att två organisationer i samverkansorgan d.v.s. socialsekreterare och skolpersonal ansågs vara mer professionella medan personal på HVB anses vara semiprofessionella. Professionella i samverkan bör vara i solidaritet för att utföra bra arbete som gynnar ensamkommande flyktingbarn i längden. Genom attinteragera på ett bra sätt, kan det skapa möjligheter att få de ensamkommande barnen att bli mer delaktiga i olika aktiviteter som de erbjuds. Med deltagande iolika fritidsaktiviteter kan ensamkommande flyktingbarn få möjlighet att påverka och forma sin integrationsprocess.

  • Kalered, Emil
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Chemistry. Linköping University, Faculty of Science & Engineering.
    Brenning, N.
    KTH Royal Institute Technology, Sweden.
    Pilch, Iris
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Caillault, L.
    University of Paris 11, France.
    Minea, T.
    University of Paris 11, France.
    Ojamäe, Lars
    Linköping University, Department of Physics, Chemistry and Biology, Chemistry. Linköping University, Faculty of Science & Engineering.
    On the work function and the charging of small (r <= 5 nm) nanoparticles in plasmas2017In: Physics of Plasmas, ISSN 1070-664X, E-ISSN 1089-7674, Vol. 24, no 1, 013702Article in journal (Refereed)
    Abstract [en]

    The growth of nanoparticles (NPs) in plasmas is an attractive technique where improved theoretical understanding is needed for quantitative modeling. The variation of the work function W with size for small NPs, r(NP) amp;lt;= 5 nm, is a key quantity for modeling of three NP charging processes that become increasingly important at a smaller size: electron field emission, thermionic electron emission, and electron impact detachment. Here we report the theoretical values of the work function in this size range. Density functional theory is used to calculate the work functions for a set of NP charge numbers, sizes, and shapes, using copper for a case study. An analytical approximation is shown to give quite accurate work functions provided that r(NP) amp;gt; 0.4 nm, i.e., consisting of about amp;gt; 20 atoms, and provided also that the NPs have relaxed close to spherical shape. For smaller sizes, W deviates from the approximation, and also depends on the charge number. Some consequences of these results for nanoparticle charging are outlined. In particular, a decrease in W for NP radius below about 1 nm has fundamental consequences for their charge in a plasma environment, and thereby on the important processes of NP nucleation, early growth, and agglomeration. Published by AIP Publishing.

  • Potra, Sabina Alina
    et al.
    Polytech University of Timisoara, Romania.
    Izvercian, Monica
    Polytech University of Timisoara, Romania.
    Pavel Pugna, Adrian
    Polytech University of Timisoara, Romania.
    Dahlgaard, Jens Jörn
    Linköping University, Department of Management and Engineering, Logistics & Quality Management. Linköping University, Faculty of Science & Engineering.
    The HWWP, a refined IVA-Kano model for designing new delightful products or services2017In: Total quality management and business excellence (Online), ISSN 1478-3363, E-ISSN 1478-3371, Vol. 28, no 1-2, 104-117 p.Article in journal (Refereed)
    Abstract [en]

    For the last decade, companies have tried to survive in a continuous competitive global marketplace with informed and demanding customers for first-time-right delightful products and services. The present paper tries to answer the simple corporate question How to design a new product for customer delight? by exploring the relevant design requirements managers need to take into consideration for corporate strategic decision-making. After examining the ongoing debate regarding the theory of attractive quality, the Health Weapon Wealth Prospect (HWWP) model is proposed for new product or service design, which relates Maslows hierarchy of needs with the Kano methodology, importance of customer wants and the customer satisfaction coefficient. The result represents a theoretical contribution to the further development of the Kano model and a starting point for future explanatory research.

  • Mitraka, Evangelia
    et al.
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Jafari, Mohammad Javad
    Linköping University, Department of Physics, Chemistry and Biology, Molecular Physics. Linköping University, Faculty of Science & Engineering.
    Vagin, Mikhail
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Liu, Xianjie
    Linköping University, Department of Physics, Chemistry and Biology, Surface Physics and Chemistry. Linköping University, Faculty of Science & Engineering.
    Fahlman, Mats
    Linköping University, Department of Physics, Chemistry and Biology, Surface Physics and Chemistry. Linköping University, Faculty of Science & Engineering.
    Ederth, Thomas
    Linköping University, Department of Physics, Chemistry and Biology, Molecular Physics. Linköping University, Faculty of Science & Engineering.
    Berggren, Magnus
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Jonsson, Magnus
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Crispin, Xavier
    Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering.
    Oxygen-induced doping on reduced PEDOT2017In: Journal of Materials Chemistry A, ISSN 2050-7488, Vol. 5, no 9, 4404-4412 p.Article in journal (Refereed)
    Abstract [en]

    The conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) has shown promise as air electrode in renewable energy technologies like metal-air batteries and fuel cells. PEDOT is based on atomic elements of high abundance and is synthesized at low temperature from solution. The mechanism of oxygen reduction reaction (ORR) over chemically polymerized PEDOT: Cl still remains controversial with eventual role of transition metal impurities. However, regardless of the mechanistic route, we here demonstrate yet another key active role of PEDOT in the ORR mechanism. Our study demonstrates the decoupling of conductivity (intrinsic property) from electrocatalysis (as an extrinsic phenomenon) yielding the evidence of doping of the polymer by oxygen during ORR. Hence, the PEDOT electrode is electrochemically reduced (undoped) in the voltage range of ORR regime, but O-2 keeps it conducting; ensuring PEDOT to act as an electrode for the ORR. The interaction of oxygen with the polymer electrode is investigated with a battery of spectroscopic techniques.

  • Public defence: 2017-05-04 09:00 Belladonna, Hus 511, Linköping
    Chenna Narendra, Sudeep
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences.
    Systemic and local regulation of experimental arthritis by IFN-α, dendritic cells and uridine2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In this thesis, we have studied the immunological processes of joint inflammation that may be targets for future treatment of patients with arthritis. We focus on the immune-modulating properties of interferon-α (IFN-α) and uridine in experimental arthritis. The nucleoside uridine, which is regarded a safe treatment has anti-inflammatory properties notably by inhibiting tumor necrosis factor (TNF) release. Because the inflamed synovium in rheumatoid arthritis (RA) is characterised by pathogenic TNF-production, uridine could potentially be away to ameliorate arthritis. Systemic administration of uridine had no effect on antigeninduced arthritis (AIA), which is a T-cell dependent model where animals are immunized twice (sensitization) with bovine serum albumin (mBSA), before local triggering of arthritis by intra-articular antigen (mBSA) re-challenge. In contrast, intra-articular administration of uridine clearly down modulated development of AIA in a dose dependent manner and inhibited the expression of synovial adhesion molecules, influx of inflammatory leukocytes and synovial expression of TNF and interleukin 6, but did not affect systemic levels of proinflammatory cytokines or antigen-specific T-cell responses. Local administration of uridine may thus be a viable therapeutic option for treatment of arthritis in the future.

    Viral double-stranded deoxyribonucleic acid (dsRNA), a common nucleic acid found in most viruses, can be found in the joints of RA patients and local deposition of such viral dsRNA induces arthritis by activating IFN-α. Here we show that arthritis induced by dsRNA can be mediated by IFN-producing dendritic cells in the joint and this may thus explain why viral infections are sometimes associated with arthritis.

    Earlier, to study the effect of dsRNA and IFN-α in an arthritis model, that like RA, is dependent on adaptive immunity, dsRNA and IFN-α were administered individually during the development of AIA. Both molecules clearly protected against AIA in a type I IFN receptor-dependent manner but were only effective if administered in the sensitization phase of AIA. Here we show that the anti-inflammatory effect of IFN-α is critically dependent on signalling via transforming growth factor β (TGF-β) and the enzymatic activity of indoleamine 2,3 dioxygenase 1 (IDO). The IDO enzyme is produced by plasmacytoid DC and this cell type was critically required both during antigen sensitization and in the arthritis phase of AIA for the protective effect of IFN-α against AIA. In contrast, TGF-β and the enzymatic activity of IDO were only required during sensitization, which indicate that they are involved in initial steps of tolerogenic antigen sensitization. In this scenario, IFN- α first activates the enzymatic activity of IDO in pDC, which converts Tryptophan to Kynurenine, which thereafter activates TGF-β. Common for IDO-expressing pDC, Kyn and TGF-β is their ability to induce development of regulatory T cells (Tregs). We found that Tregs were crucial for IFN-α-mediated protection against AIA, but only in the arthritis phase. In line with this, adoptive transfer of Tregs isolated from IFN-α treated mice to recipient animals in the arthritis phase clearly protected against AIA. The numbers of Tregs were not significantly altered by IFN-α but IFN-α increased the suppressive capacity of Tregs against antigen-induced proliferation. This enhanced suppressive activity of Tregs in the arthritis phase was dependent on the earlier activated enzyme IDO1 during the sensitization phase of AIA. Thus, presence of IFN-α at the time of antigen sensitization activates the enzymatic activity of IDO, which generates Tregs with enhanced suppressive capacity that upon antigen re-challenge prevents inflammation. We have thus identified one example of how immune tolerance can be developed, that may be a future way to combat autoimmunity.

    List of papers
    1. Local but Not Systemic Administration of Uridine Prevents Development of Antigen-Induced Arthritis
    Open this publication in new window or tab >>Local but Not Systemic Administration of Uridine Prevents Development of Antigen-Induced Arthritis
    2015 (English)In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 10, no 10, e0141863- p.Article in journal (Refereed) Published
    Abstract [en]

    Objective Uridine has earlier been show to down modulate inflammation in models of lung inflammation. The aim of this study was to evaluate the anti-inflammatory effect of uridine in arthritis. Methods Arthritis was induced by intra-articular injection of mBSA in the knee of NMRI mice preimmunized with mBSA. Uridine was either administered locally by direct injection into the knee joint or systemically. Systemic treatment included repeated injections or implantation of a pellet continuously releasing uridine during the entire experimental procedure. Anti-mBSA specific immune responses were determined by ELISA and cell proliferation and serum cytokine levels were determined by Luminex. Immunohistochemistry was used to identify cells, study expression of cytokines and adhesion molecules in the joint. Results Local administration of 25-100 mg/kg uridine at the time of arthritis onset clearly prevented development of joint inflammation. In contrast, systemic administration of uridine (max 1.5 mg uridine per day) did not prevent development of arthritis. Protection against arthritis by local administration of uridine did not affect the anti-mBSA specific immune response and did not prevent the rise in serum levels of pro-inflammatory cytokines associated with the triggering of arthritis. In contrast, local uridine treatment efficiently inhibited synovial expression of ICAM-1 and CD18, local cytokine production and recruitment of leukocytes to the synovium. Conclusion Local, but not systemic administration of uridine efficiently prevented development of antigen- induced arthritis. The protective effect did not involve alteration of systemic immunity to mBSA but clearly involved inhibition of synovial expression of adhesion molecules, decreased TNF and IL-6 production and prevention of leukocyte extravasation. Further, uridine is a small, inexpensive molecule and may thus be a new therapeutic option to treat joint inflammation in RA.

    Place, publisher, year, edition, pages
    PUBLIC LIBRARY SCIENCE, 2015
    National Category
    Clinical Medicine
    Identifiers
    urn:nbn:se:liu:diva-123070 (URN)10.1371/journal.pone.0141863 (DOI)000363920300089 ()26512984 (PubMedID)
    Note

    Funding Agencies|Vetenskapsradet-Grant [521-2011-3095]; Reumatikerforbundet Grant [155261]; County Council of Ostergotland, Sweden; Linkoping University

    Available from: 2015-12-04 Created: 2015-12-03 Last updated: 2017-03-31
    2. IDO1 and TGF-beta Mediate Protective Effects of IFN-alpha in Antigen-Induced Arthritis
    Open this publication in new window or tab >>IDO1 and TGF-beta Mediate Protective Effects of IFN-alpha in Antigen-Induced Arthritis
    Show others...
    2016 (English)In: Journal of Immunology, ISSN 0022-1767, E-ISSN 1550-6606, Vol. 197, no 8, 3142-3151 p.Article in journal (Refereed) Published
    Abstract [en]

    IFN-alpha prevents Ag-induced arthritis (AIA), and in this study we investigated the role of IDO1 and TGF-beta signaling for this anti-inflammatory property of IFN-alpha. Arthritis was induced by methylated BSA (mBSA) in mBSA-sensitized wild-type (WT), Ido1(-/-), or Ifnar(-/-) mice, treated or not with IFN-alpha or the IDO1 product kynurenine (Kyn). Enzymatic IDO1 activity, TGF-beta, and plasmacytoid dendritic cells (pDC) were neutralized by 1-methyltryptophan and Abs against TGF-beta and pDC, respectively. IDO1 expression was determined by RT-PCR, Western blot, and FACS, and enzymatic activity by HPLC. Proliferation was measured by H-3-thymidine incorporation and TGF-beta by RT-PCR and ELISA. WT but not Ido1(-/-) mice were protected from AIA by IFN-alpha, and Kyn, the main IDO1 product, also prevented AIA, both in WTand Ifnar(-/-) mice. Protective treatment with IFN-alpha increased the expression of IDO1 in pDC during AIA, and Ab-mediated depletion of pDC, either during mBSA sensitization or after triggering of arthritis, completely abrogated the protective effect of IFN-alpha. IFN-alpha treatment also increased the enzymatic IDO1 activity (Kyn/tryptophan ratio), which in turn activated production of TGF-beta. Neutralization of enzymatic IDO1 activity or TGF-beta signaling blocked the protective effect of IFN-alpha against AIA, but only during sensitization and not after triggering of arthritis. Likewise, inhibition of the IDO1 enzymatic activity in the sensitization phase, but not after triggering of arthritis, subdued the IFN-alpha-induced inhibition of mBSA-induced proliferation. In conclusion, presence of IFN-alpha at Ag sensitization activates an IDO1/TGF-beta-dependent anti-inflammatory program that upon antigenic rechallenge prevents inflammation via pDC.

    Place, publisher, year, edition, pages
    AMER ASSOC IMMUNOLOGISTS, 2016
    National Category
    Immunology in the medical area
    Identifiers
    urn:nbn:se:liu:diva-133121 (URN)10.4049/jimmunol.1502125 (DOI)000387965100018 ()27647832 (PubMedID)
    Available from: 2016-12-12 Created: 2016-12-09 Last updated: 2017-04-24
    3. Dendritic cells activated by double-stranded RNA induce arthritis via autocrine type I IFN signaling.
    Open this publication in new window or tab >>Dendritic cells activated by double-stranded RNA induce arthritis via autocrine type I IFN signaling.
    2014 (English)In: Journal of Leukocyte Biology, ISSN 0741-5400, E-ISSN 1938-3673, Vol. 95, no 4, 661-666 p.Article in journal (Refereed) Published
    Abstract [en]

    Viral dsRNA can be found at the site of inflammation in RA patients, and intra-articular injection of dsRNA induces arthritis by activating type I IFN signaling in mice. Further, DCs, a major source of IFN-α, can be found in the synovium of RA patients. We therefore determined the occurrence of DCs in dsRNA-induced arthritis and their ability to induce arthritis. Here, we show, by immunohistochemistry, that cells expressing the pan-DC marker CD11c and the pDC marker 120G8 are present in the inflamed synovium in dsRNA-induced arthritis. Flt3L-generated and splenic DCs preactivated with dsRNA before intra-articular injection, but not mock-stimulated cells, clearly induced arthritis. Induction of arthritis was dependent on type I IFN signaling in the donor DCs, whereas IFNAR expression in the recipient was not required. Sorting of the Flt3L-DC population into cDCs (CD11c(+), PDCA-1(-)) and pDCs (CD11c(+), PDCA-1(+)) revealed that both subtypes were arthritogenic and produced type I IFN if treated with dsRNA. Taken together, these results demonstrate that viral nucleic acids can elicit arthritis by activating type I IFN signaling in DCs. Once triggered, autocrine type I IFN signaling in dsRNA-activated DCs is sufficient to propagate arthritis.

    Place, publisher, year, edition, pages
    Society for Leukocyte Biology, 2014
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-102370 (URN)10.1189/jlb.0613320 (DOI)000335346300011 ()24304616 (PubMedID)
    Available from: 2013-12-09 Created: 2013-12-09 Last updated: 2017-03-31
  • Aminoff, Christina
    Linköping University, Department of Behavioural Sciences and Learning, Education, Teaching and Learning. Linköping University, Faculty of Educational Sciences.
    Samtals- och skriftspråksorienterade lärarledda aktiviteter i förskoleklass2017Licentiate thesis, monograph (Other academic)
    Abstract [sv]

    Syftet med studien är att bidra med kunskaper om förskoleklassens verksamhet med fokus på lärares och barns handlingar i samtals- och skriftspråksorienterade lärarledda aktiviteter. Centrala frågor i studien handlar om vad som händer i mötet mellan läraren och barnen och vilka förutsättningar för barns samtalande och skriftspråkande som skapas i interaktion mellan läraren och barnen i de lärarledda aktiviteterna.

    Metoden har inspiration av etnografisk ansats. Datamaterial består framför allt av delvis deltagande observationer där fältanteckningar skrivits för att dokumentera dessa. I studien ingår tre förskoleklasser från tre olika skolor. Varje förskoleklass har observerats vid sju tillfällen. Datamaterialet har analyserats med hjälp av tematisk analys, begrepp från tidigare forskning samt utifrån studiens teoretiska utgångspunkt, det sociokulturella perspektivet.

    Av resultat framgår att alla barn till stora delar gör samma övningar under de lärarledda aktiviteterna. Läraren och barnen rör sig i höglästa berättelser på ett såväl intratextuellt som intertextuellt sätt och när de tillsammans arbetar med att skriva så förekommer både ett styrt och ett friare skrivande. Resultat visar även att det förekommer en viss upprepning av ett innehåll som vissa barn har kunskap och erfarenhet av sedan tidigare, exempelvis från förskolan.            

     

  • Sandberg, Hugo
    Linköping University, Department for Studies of Social Change and Culture, Department of History, Tourism and Media.
    Plikten att skydda sitt barn: En undersökning av ansökningarna om undantag från det svenska vaccinationsobligatoriet 1917-19202016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Denna uppsats undersöker ansökningar från 1917-1920 som föräldrar gjorde för att undanta sina barn från den obligatoriska smittkoppsvaccinationen. Dessa ansökningar var en del av den vaccinkritiska debatten och rörelsen som var stark kring sekelskiftet 1900. Genom att undersöka dessa ansökningar framträder en bild av de individer som motsatte sig myndigheterna och stora delar av läkarkåren.

    De ansökande kom från varierande bakgrund men vissa grupper och geografiska regioner är överrepresenterade. I undersökningsmaterialet framträder prästerskapet och de frikyrkliga områdena runt Jönköping som särskilt benägna att vilja undanta sina barn från vaccinationen. 

    Myndigheterna kom att avslå 54 av de 58 undersökta ansökningarna. Den gemensamma nämnaren för de ansökningar som vann bifall var att de alla presenterade vaccinskadefall som överensstämde med de krav som 1917 års samvetsklausul ställde.

    Som teoretiskt hjälpmedel har uppsatsen använt John Rawls lagkritiska handlingar civil olydnad och samvetsvägran. Dessa har också fått var sin kompletterande icke-lagbrytande motsvarighet. Undersökningen visar att majoriteten av ansökningarna primärt var handlingar av samvetsvägran, en opolitisk handling som också kunde vara lagbrytande om den inte vann bifall. Det var föräldrar som ville skydda sina barn mot något de ansåg vara skadligt. 

  • Olausson, Albin
    et al.
    Linköping University, Department of Management and Engineering, Political Science. Linköping University, Faculty of Arts and Sciences.
    Syssner, Josefina
    Linköping University, Department for Studies of Social Change and Culture, Centre for Municipality Studies – CKS. Linköping University, Faculty of Arts and Sciences.
    Att stärka den lokala attraktionskraften: Målbilder och genomförande i den lokala utvecklingspolitiken2017Report (Other academic)
    Abstract [sv]

    Under de senaste decennierna har statens möjligheter att med reformprogram genomdriva omfattande och politiska motiverade samhällsförändringar ifrågasatts allt mer. Det har sagts att staten varken kan eller bör försöka styra samhällsutvecklingen uppifrån. Inte minst gäller detta inom det regionalpolitiska fältet.

    Mot bakgrund av detta har Sveriges kommuner kommit att spela en allt viktigare roll i arbetet med att skapa tillväxt och utveckling i hela landet. Demografiska och ekonomiska strukturförändringar i kombination med föreställningar om att platser konkurrerar med varandra om invånare, besökare och investerare har också varit avgörande faktorer för kommunernas ökade intresse för lokala utvecklingsfrågor. Men hur bedrivs egentligen lokalt utvecklingsarbete i svenska kommuner?

    Syftet med denna rapport är att bidra med en ökad förståelse för hur svenska kommuner arbetar med lokal utveckling. Rapporten bygger på en studie där vi intervjuat 34 kommunala företrädare om hur de ser på det lokala utvecklingsarbete som bedrivs i deras respektive kommuner. I vår analys har vi intresserat oss för hur frågor om lokal utveckling och attraktionskraft hanteras på kommunal strategisk nivå, i synnerhet i relation till andra lokala aktörer.

    Rapporten slår fast att många informanter uppehåller sig kring två specifika teman; dels de målbilder som finns för kommunens arbete med lokal utveckling, dels kommunens övergripande strategier för genomförande av lokalt utvecklingsarbete. Genom att sortera intervjupersonernas utsagor utifrån dessa två teman kan vi se att det finns en stark uppfattning om att kommunerna har för otydliga målbilder för det lokala utvecklingsarbetet. Dessutom menar intervjupersonerna att kommunen arbetar för enskilt i arbetet med att genomföra lokala utvecklingsinsatser. Istället efterfrågar de kommunala företrädare vi intervjuat tydligare och mer enhetliga målbilder för lokalsamhällets utveckling på lång sikt. Förutom det menar de vi intervjuat att kommunen även måste utveckla strategier för att genomföra dessa målbilder i interaktion med medborgarna, föreningslivet och det lokala näringslivet.

    Den viljeriktning som studiens intervjupersoner visar på ser vi som ett uttryck för ett ständigt sökande efter effektivare och mer legitima sätt att arbeta med lokal utveckling. Vi ser dock att det kan finnas skäl till att vara kritisk mot idén om att en enhetlig målbild kan diskuteras fram i bred överenskommelse och genomföras i interaktion mellan kommun, medborgare, förenings-liv och näringsliv. Det kan vara ett förenklat sätt att se på demokratiskt beslutsfattande. Vidare har det påpekats att den typen av beslutsprocesser och styrning inte sällan gynnar redan resursstarka parter och försvårar ansvars-utkrävande.

  • Public defence: 2017-05-12 10:15 Alan Turing, hus E, Linköping
    Andersson, Anders
    Linköping University, Department of Computer and Information Science. Linköping University, Faculty of Science & Engineering. Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
    Extensions for Distributed Moving Base Driving Simulators2017Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Modern vehicles are complex systems. Different design stages for such a complex system include evaluation using models and submodels, hardware-in-the-loop systems and complete vehicles. Once a vehicle is delivered to the market evaluation continues by the public. One kind of tool that can be used during many stages of a vehicle lifecycle is driving simulators.

    The use of driving simulators with a human driver is commonly focused on driver behavior. In a high fidelity moving base driving simulator it is possible to provide realistic and repetitive driving situations using distinctive features such as: physical modelling of driven vehicle, a moving base, a physical cabin interface and an audio and visual representation of the driving environment. A desired but difficult goal to achieve using a moving base driving simulator is to have behavioral validity. In other words, \A driver in a moving base driving simulator should have the same driving behavior as he or she would have during the same driving task in a real vehicle.".

    In this thesis the focus is on high fidelity moving base driving simulators. The main target is to improve the behavior validity or to maintain behavior validity while adding complexity to the simulator. One main assumption in this thesis is that systems closer to the final product provide better accuracy and are perceived better if properly integrated. Thus, the approach in this thesis is to try to ease incorporation of such systems using combinations of the methods hardware-in-the-loop and distributed simulation. Hardware-in-the-loop is a method where hardware is interfaced into a software controlled environment/simulation. Distributed simulation is a method where parts of a simulation at physically different locations are connected together. For some simulator laboratories distributed simulation is the only feasible option since some hardware cannot be moved in an easy way.

    Results presented in this thesis show that a complete vehicle or hardware-in-the-loop test laboratory can successfully be connected to a moving base driving simulator. Further, it is demonstrated that using a framework for distributed simulation eases communication and integration due to standardized interfaces. One identified potential problem is complexity in interface wrappers when integrating hardware-in-the-loop in a distributed simulation framework. From this aspect, it is important to consider the model design and the intersections between software and hardware models. Another important issue discussed is the increased delay in overhead time when using a framework for distributed simulation.

    List of papers
    1. Vehicle Powertrain Test Bench Co-Simulation with a Moving Base Simulator Using a Pedal Robot
    Open this publication in new window or tab >>Vehicle Powertrain Test Bench Co-Simulation with a Moving Base Simulator Using a Pedal Robot
    2013 (English)In: SAE International Journal of Passenger Cars - Electronic and Electrical Systems, ISSN 1946-4614, E-ISSN 1946-4622, Vol. 6, no 1, 169-179 p.Article in journal (Refereed) Published
    Abstract [en]

    To evaluate driver perception of a vehicle powertrain a moving base simulator is a well-established technique. We are connecting the moving base simulator Sim III, at the Swedish National Road and Transport Research Institute with a newly built chassis dynamometer at Vehicular Systems, Linköping University. The purpose of the effort is to enhance fidelity of moving base simulators by letting drivers experience an actual powertrain. At the same time technicians are given a new tool for evaluating powertrain solutions in a controlled environment. As a first step the vehicle model from the chassis dynamometer system has been implemented in Sim III. Interfacing software was developed and an optical fiber covering the physical distance of 500 m between the facilities is used to connect the systems. Further, a pedal robot has been developed that uses two linear actuators pressing the accelerator and brake pedals. The pedal robot uses feedback loops on accelerator position or brake cylinder pressure and is controlled via an UDP interface. Results from running the complete setup showed expected functionality and we are successful in performing a driving mission based on real road topography data. Vehicle acceleration and general driving feel was perceived as realistic by the test subjects while braking still needs improvements. The pedal robot construction enables use of a large set of cars available on the market and except for mounting the brake pressure sensor the time to switch vehicle is approximately 30 minutes.

    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-92215 (URN)10.4271/2013-01-0410 (DOI)
    Available from: 2013-05-08 Created: 2013-05-08 Last updated: 2017-04-07Bibliographically approved
    2. Models for Distributed Real-Time Simulation in a Vehicle Co-Simulator Setup
    Open this publication in new window or tab >>Models for Distributed Real-Time Simulation in a Vehicle Co-Simulator Setup
    2013 (English)In: Proceedings of the 5th International Workshop on Equation-Based Object-Oriented Modeling Languages and Tools; April 19, University of Nottingham, Nottingham, UK / [ed] Henrik Nilsson, Linköping: Linköping University Electronic Press, 2013, Vol. 84, 131-139 p.Conference paper (Refereed)
    Abstract [en]

    A car model in Modelica has been developed to be used in a new setup for distributed real-time simulation where a moving base car simulator is connected with a real car in a chassis dynamometer via a 500m fiber optic communication link. The new co-simulator set-up can be used in a number of configurations where hardware in the loop can be interchanged with software in the loop. The models presented in this paper are the basic blocks chosen for modeling the system in the context of a distributed real-time simulation; estimating parameters for the powertrain model; the choice of numeric solver; and the interaction with the solver for real-time properties.

    Place, publisher, year, edition, pages
    Linköping: Linköping University Electronic Press, 2013
    Series
    Linköping Electronic Conference Proceedings, ISSN 1650-3686 (print), 1650-3740 (online) ; 84
    Keyword
    Modelica; real-time; distributed; communications link
    National Category
    Computer Systems
    Identifiers
    urn:nbn:se:liu:diva-118994 (URN)978-91-7519-621-3 (ISBN)978-91-7519-617-6 (ISBN)
    Conference
    The 5th International Workshop on Equation-Based Object-Oriented Modeling Languages and Tools, April 19, University of Nottingham, Nottingham; UK
    Available from: 2015-06-05 Created: 2015-06-05 Last updated: 2017-04-07Bibliographically approved
    3. A Driving Simulation Platform using Distributed Vehicle Simulators and HLA
    Open this publication in new window or tab >>A Driving Simulation Platform using Distributed Vehicle Simulators and HLA
    Show others...
    2015 (English)In: Proceedings of the DSC 2015 Europe: Driving Simulation Conference & Exhibition / [ed] Heinrich Bülthoff, Andras Kemeny and Paolo Pretto, 2015, 123-130 p.Conference paper (Refereed)
    Abstract [en]

    Modern vehicles are complex systems consisting of an increasing large multitude of components that operate together. While functional verification on individual components is important, it is also important to test components within a driving environment, both from a functional perspective and from a driver perspective. One proven way for testing is vehicle simulators and in this work the main goals have been to increase flexibility and scalability by introducing a distributed driving simulator platform.

    As an example, consider a workflow where a developer can go from a desktop simulation to an intermediate driving simulator to a high fidelity driving simulator with Hardware-In-the-Loop systems close to a finished vehicle in an easy way. To accomplish this, a distributed simulation architecture was designed and implemented that divides a driving simulator environment into four major entities with well-defined interfaces, using HLA as the method of communication. This platform was evaluated on two aspects, flexibility/scalability and timing performance. Results show that increased flexibility and scalability was achieved when using a distributed simulation platform. It is also shown that latency was only slightly increased when using HLA.

    Keyword
    Test, Vehicle, Engine, Performance, Simulator (driving), Computer
    National Category
    Computer Systems
    Research subject
    90 Road: Vehicles and vehicle technology, 911 Road: Components of the vehicle; 90 Road: Vehicles and vehicle technology, 96 Road: Vehicle operating and management
    Identifiers
    urn:nbn:se:liu:diva-136153 (URN)9783981309935 (ISBN)
    Conference
    Driving Simulation Conference 2015. 16-18 september 2015, Tübingen, Germany
    Available from: 2016-01-11 Created: 2017-03-31 Last updated: 2017-04-06Bibliographically approved
  • Waern, Sandra
    Linköping University, Department of Physics, Chemistry and Biology.
    Microalgae: A Green Purification of Reject Water for Biogas Production2016Independent thesis Advanced level (degree of Master (Two Years)), 300 HE creditsStudent thesis
    Abstract [en]

    Microalgae are a diverse group of unicellular microorganisms found in various environments, ranging from small garden ponds to lakes with extreme salinity. Common for all microalgae is their ability to convert solar energy and carbon dioxide into chemical energy via photosynthesis. Additionally, they are capable of assimilating large amounts of nitrogen and phosphorus to produce proteins and lipids. These abilities have made microalgae an interesting candidate for next generation wastewater treatment coupled with production of biogas, a renewable energy source in advancement. At the Nykvarn wastewater treatment plant in Linköping, Sweden, 15,400,000 m3 of wastewater are treated annually to remove nitrogen and phosphorus that otherwise would risk to cause eutrophication in surrounding lakes and rivers. Moreover, the treatment plant manages large amounts of sewage sludge that is anaerobically digested to produce biogas and simultaneously reduce the sludge volumes. At the Nykvarn wastewater treatment plant, dewatering of the digested sludge results in a sludge fraction of about 30 % dry content and reject water, which is very nutrient-rich and therefore requires treatment in a SHARON process before it is reintroduced to the main stream of the wastewater treatment plant.

    In this thesis, the potential of microalgae for nutrient assimilation was studied by monitoring the nutrient removal efficiency of a mixed culture of microalgae when fed with 1) 100 % incoming wastewater, 2) 80 % incoming wastewater + 20 % reject water and 3) 60 % incoming wastewater + 40 % reject water. Furthermore, the effect of a process additive on the nutrient removal efficiency was evaluated. The results showed that microalgae are capable of removing 100 % of ingoing ammonium nitrogen and phosphate phosphorus when fed with incoming wastewater. At transition to 20 % and 40 % reject water, the culture was light-limited with a resulting ammonium reduction of 60 % and a phosphate reduction of around 30 %. The process additive slightly improved the ammonium reduction, however, mainly by formation of nitrite and nitrate by nitrifying bacteria. Moreover, a bio-methane potential test compared the methane potential of the microalgal biomass and the biomass from the SHARON process. The test resulted in an accumulated methane production around 70 mL g-1 VS-1 for the microalgal biomass and 35 mL g-1 VS-1 for the biomass from the SHARON process. That is, the mixed microalgal culture used in this experiment has a methane potential twice that of the biomass from the SHARON process. Finally, an economic analysis of a microalgae based process for purification of reject water showed that the operating costs exceed those of the SHARON process due to high energy consumption. It is thus necessary to choose a cultivation system that effectively utilize the solar energy, as well as maximize the biogas yield from anaerobic digestion of microalgal biomass.

  • Fritsche, Carsten
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, Faculty of Science & Engineering.
    On parametric smoothing Cramér-Rao bounds2017Report (Other academic)
    Abstract [en]

    In this report, the parametric Cramér-Rao lower bound for the smoothing problem is derived.