liu.seSearch for publications in DiVA
Change search
Refine search result
2018201920202021202220232024 101001 - 101050 of 101516
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 101001.
    Örjestam, Kristoffer
    Linköping University, Department of Culture and Communication.
    Föreställningen om idealkvinnan: Det konstruerade pastorala kvinnoporträttet under frihetstiden2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    An analysis of the female constructed gender and it's display in the pastoral portrait during the first half of the 18th century in Sweden. By looking at the kontext of the time an through analyzing three portraits the matter of woman as an ideal will be explored.

  • 101002. Örlyggsson, Johan
    et al.
    Andersson, Rolf
    Svensson, Bo
    Linköping University, Faculty of Arts and Sciences. Linköping University, The Tema Institute, Department of Water and Environmental Studies.
    Alanine as an end product during fermentation of monosacharides by Clostridium strain P21995In: Antonie van Leeuwenhoek. International Journal of General and Molecular Microbiology, ISSN 0003-6072, E-ISSN 1572-9699, Vol. 68, p. 273-280Article in journal (Refereed)
  • 101003.
    Örn, Daniel
    et al.
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, Faculty of Science & Engineering.
    Szilassy, Martin
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, Faculty of Science & Engineering.
    Dil, Bram
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, Faculty of Science & Engineering.
    Gustafsson, Fredrik
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, Faculty of Science & Engineering.
    A Novel Multi-Step Algorithm for Low-Energy Positioning Using GPS2016In: Fusion 2016, 19th International Conference on Information Fusion: Proceedings, 2016, p. 1469-1476Conference paper (Refereed)
    Abstract [en]

    GPS is widely used for localization and tracking, however traditional GPS receivers consume too much energy for many applications. This paper implements and evaluates the performance of a low-energy GPS prototype. The main difference is that a traditional GPS needs to sample signals transmitted by satellites for 30 seconds to estimate its position. Our prototype reduces this time by three orders of magnitude and it can compute positions from only 2 milliseconds of data. We present a new algorithm that increases robustness by filtering on estimated residuals instead of using an altitude database. In addition, we show that our new algorithm works with both fixed and moving targets. The solution consists of (1) a portable device that samples the GPS signal and (2) a server that utilizes Doppler navigation and Coarse Time Navigation to estimate positions. We performed tests in a wide variety of environments and situations. These tests show that our prototype provides a median positioning error of roughly 40 meters even when the GPS receiver is moving at 80 kilometres per hour.

  • 101004.
    Örn, Markus
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology.
    Towards Better Alternator Efficiency2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The requirements on vehicle industry are constantly getting stricter, especially when it comes to emissions. At the same time cars, trucks and buses are needed for our way of living. This have forced companies to be as ecient as possible in their way of using fossil fuels for travelling and transport. To increase the eciency companies investigate all possible fuel savings to decrease their carbon footprint as much as possible. One area of savings that is not that obvious to many people is the alternator. Several percent of the total energy used by a vehicle are needed to operate the alternator. With a typical alternator eciency of 70% considerable savings can be achieved.

    This thesis that concern alternator eciency was carried out at Scania in Södertälje, Sweden. The goal of the thesis is to construct a mathematical model of an alternator. The model is supposed to consider all losses in the alternator and together with the output power give an eciency model of the alternator at different speeds and loads. A great part of the project has been dealing with the magnetic losses. The magnetic losses have been modeled as an equivalent circuit with the load angle as a central piece. The equivalent circuit is built up by the fact that the alternator used in the vehicles is a salient pole alternator. The equivalent circuit describes a voltage equation where the voltage drop over the magnetic inductance is described. From that relations between the signals in the alternator and output signals can be written.

    The alternator model is then used together with data recorded from different buses all over the world, this to be able to investigate how the alternator contributes to the fuel consump- tion depending on the way that the buses are driven.

    The result of this thesis is a mathematical model that describes the losses in the alternator for different load cases and speeds. 

  • 101005.
    Örn, Sara
    Linköping University, Department of Electrical Engineering, Communication Systems. Linköping University, The Institute of Technology.
    Realistic Multi-Cell Interference Coordination in 4G/LTE2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In the LTE mobile system, all cells use the same set of frequencies. This means that a user could experience interference from other cells. A method that has been studied in order to reduce this interference and thereby increase data rate or system throughput is to coordinate scheduling between cells. Good results of this have been found in different studies. However, the interference is generally assumed to be known. Studies using estimated interference and simulating more than one cluster of cells have found almost no gain.

    This thesis will focus on how to use information from coordinated scheduling and other traffic estimates to do better interference estimation and link adaption. The suggested method is to coordinate larger clusters and use the coordination information, as well as estimates of which cells will be transmitting, to make estimates of interference from other cells. The additional information from interference estimation is used in the link adaptation. Limitations in bandwidth of the backhaul needed to send data between cells are considered, as well as the delay it may introduce. A limitation of the scope is that MIMO or HetNet scenarios have not been simulated.

    The suggested method for interference estimation and link adaptation have been implemented and simulated in a system simulator. The method gives a less biased estimate of SINR, but there are no gains in user bit rate. The lesser bias is since the method is better at predicting high SINR than the base estimate is. The lack of gains regarding user bit rate may result from the fact that in the studied scenarios, users where not able to make use of the higher estimated SINR since the base estimate is already high.

    The conclusion is that the method might be useful in scenarios where there are not full load, but the users either have bad channel quality or are able to make use of very high SINR. Such scenarios could be HetNet or MIMO scenarios, respectively.

  • 101006.
    Örnberg Berglund, Therese
    Linköping University, Department of Culture and Communication, Modern Languages. Linköping University, Faculty of Arts and Sciences.
    Text-based chat and language learning: opportunities and challenges2013In: Språk i undervisning: rapport från ASLA:s vårsymposium, Linköping, 11-12 maj, 2012 / [ed] Christina Rosén, Per Simfors, Ann-Kari Sundberg, Uppsala: ASLA (Institutionen för Nordiska språk, Uppsala universitet) , 2013, p. 139-149Chapter in book (Other academic)
    Abstract [en]

    The aim of the current article is to discuss opportunities and challenges with employing text-based interaction in the language classroom. These issues are addressed in relation to empirical data from a Swedish upper secoondary school, where students of English interact with a teacher (the researcher) in instant messaging. In order to gain a detailed picture of the interactional processes, data from chat logs are complemented with screen recordings, keystroke logging data and data from eye tracking. It should be noted that the current article cannot give a comprehensive account of all relevant phenomena and previous research, but rather some identified pattems will be highlighted and discussed.

  • 101007.
    Örnberg, Dennis
    Linköping University, Department of Computer and Information Science, Database and information techniques.
    Comparison and implementation of graph visualization algorithms using JavaFX2016Independent thesis Basic level (university diploma), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    Graph drawing is an important area in computer science and it has many different application areas. For example, graphs can be used to visualize structures like networks and databases. When the graphs are really big, however, it becomes difficult to draw them so that the user can get a good overview of the whole graph and all of its data. There exist a number of different algorithms that can be used to draw graphs, but they have a lot of differences. The goal of this report was to find an algorithm that produces graphs of satisfying quality in little time for the purpose of ontology engineering, and implement it using a platform that visualizes the graph using JavaFX. It is supposed to work on a visualization table with a touch display. A list of criteria for both the algorithm and the application was made to ensure that the final result would be satisfactory. A comparison between four well-known graph visualization algorithms was made and “GEM” was found to be the best suited algorithm for visualizing big graphs. The two platforms Gephi and Prefux were introduced and compared to each other, and the decision was made to implement the algorithm in Prefux since it has support for JavaFX. The algorithm was implemented and evaluated, it was found to produce visually pleasing graphs within a reasonable time frame. A modified version of the algorithm called GEM-2 was also introduced, implemented and evaluated. With GEM-2, the user can pick a specific number of levels to be expanded at first, additional levels can then be expanded by hand. This greatly improves the performance when there is no need to expand the whole graph at once, however, it also increases the amount of edge crossings which makes the graph less visually pleasing.

  • 101008.
    Örnerheim, Mattias
    Linköping University, Department of Management and Engineering, Political Science. Linköping University, The Institute of Technology.
    Entrepreneurial actors between two systems of norms - Profound and professional quality knowledge in Swedish health care2011Conference paper (Other academic)
  • 101009.
    Örnerheim, Mattias
    Linköping University, Department of Management and Engineering, Political Science. Linköping University, The Institute of Technology.
    Kvalitetsbegreppet i lagstiftningen inom den mänskliga sektorn: - en översikt2013Report (Other (popular science, discussion, etc.))
    Abstract [sv]

    Denna undersökning behandlar hur olika kvalitetsaspekter i några utvalda sektorslagar förhåller sig till varandra inom hälso- och sjukvård, polis- och kriminalvård, utbildning samt vissa kommunala lagar. Alla befinner sig i den s.k. mänskliga sektorn av offentlig verksamhet. Den bakomliggande orsaken till detta är att Innovationsrådet vill fördjupa kunskapen om hur begreppet kvalitet definieras och används i svensk lagstiftning och i förarbetena till vissa lagar. Undersökningen strävar inte efter att generera någon legaldefinition av begreppet kvalitet.

    Kvalitetsbegreppet delas in i aspekterna; struktur, process och resultat i en analysmodell i form av en matris som även tar hänsyn till personal och medborgarperspektiv. Strukturkvalitet speglar förutsättningarna för eller inflödet i en verksamhet, processkvalitet belyser de aktiviteter som görs i verksamheten och resultatkvalitet återger prestationerna och effekterna av verksamheten. Med hjälp av analysmodellen skapas ett mönster över vilka aspekter som tydligast framträder i lagarna och förarbeten samt vilket perspektiv som är mest påtagligt i respektive lag. Genom analysmodellen har en överblick över varje sektor kunnat ges.

    Undersökningen är en dokumentstudie och baseras på lagtexter med relaterade propositioner samt statliga utredningar. De utvalda lagarna återfinns i bilaga 1. I analysen av materialet har först kvantitativa sökningar gjort på kvalitet och relaterade begrepp såsom kvalitetssäkring, kvalitetsgranskning, kvalitetskontroll samt kvalitetsutvärdering för att få en bild av om kvalitet är ett återkommande begrepp eller inte. Därefter har en granskning och tolkning gjorts för att utreda ur vilka aspekter som kvalitet beskrivs, samt vilket perspektiv som väger tyngst i skrivningar i lagen och dess förarbeten.

    Varje sektor är resultatredovisad för sig i särskilda avsnitt. Resultaten visar att kvalitetsbegreppet inom hälso- och sjukvården är frekvent förekommande ur aspekterna struktur och resultat, medan resultatkvalitet överlämnats till den autonoma medicinska professionen att definiera. I utbildningssektorn tycks förhållandet vara det motsatta där resultatkvalitet i form av måluppfyllelse är det centrala och betonas starkt även kvalitet i termer av struktur och process förekommer. Även i denna sektor lyfter lagstiftaren fram autonomi och egenkontroll i avseende på utbildning och forskning när det gäller att definiera vad som är god kvalitet i vetenskapliga processer och resultat.

    Inom socialtjänsten pågår ett arbete som syftar till att ta fram kvalitetsindikatorer ur olika aspekter inspirerat av hälso- och sjukvården. Idag är begreppet kvalitet tydligast uttryckt i socialtjänstlagen när det gäller aspekterna struktur och process i ett personalperspektiv. Även inom polis och kriminalvård tycks kvalitetsbegreppet öka i betydelse även i lagtexterna, där struktur- och processaspekter framkommer i kriminalvårdens nya fängelse- och häkteslagstftningen. I polislagen lyser dock begreppet kvalitet med sin frånvaro, vilket i sig inte hindrar att krav ställs på kvalitet genom andra kanaler.

    Undersökningen avslutas med en diskussion utifrån de sektorsvisa resultaten om behov av ständigt återkommande omprövningar av hur begreppet ska användas i lagen och avvägningar om risken för cementering av verksamheter å ena sida och rättsäkerhet samt tydlighet å den andra.

  • 101010.
    Örnerheim, Mattias
    Linköping University, Department of Management and Engineering, Political Science. Linköping University, Faculty of Arts and Sciences.
    Mapping via Time-Geography to Elucidate Institutional, Economic and Political Change2012In: Proceedings of 15th Uddevalla Symposium,2012, Entrepreneurship and Innovation Networks / [ed] Iréne Bernhard, Bohus: Ale Tryckteam , 2012, p. 1-10Conference paper (Refereed)
    Abstract [en]

    Change has always been an issue for studies in politics and economics. However, there are few systematic treatments of institutions. This paper exemplifies how institutions (i.e., rules, norms and conventions) relate to the time-geography concepts of constraints, which affect different agents, policy-making, as well as economic performance.This paper seeks to advance the current discussion and sets some groundwork for further elaboration on economic and political change from an ontological perspective based in time-geography. It offers an initial exploration of the analysis of institutional change by a conceptualization of constraints in time-geography.The contribution of this study lies in the fact that insights from a time-geography approach have the ability to make the evolutionary perspective more coherent in empirically-related works when grading and ordering institutions of relevance concerning economic and political evolvement.

  • 101011.
    Örnerheim, Mattias
    Linköping University, Department of Management and Engineering, Political Science. Linköping University, The Institute of Technology.
    Marknadsskapande, valfrihet och e-hälsa i sjukvården: Utkast till avhandlingsdesign (lic.)2010Conference paper (Other academic)
  • 101012.
    Örnerheim, Mattias
    Linköping University, Department of Management and Engineering, Political Science. Linköping University, Faculty of Arts and Sciences.
    Mellan kunskap och politik: Kvalitetssystem och offentlig kunskapsstyrning i hälso- och sjukvården2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The aim with this thesis is to describe the quality development in Swedish healthcare from an institutional perspective, analyse implications of the development concerning the relationship between the medical profession and the public administrative system and discuss consequences for political direction and welfare organization. The study is based on four case studies and one conceptual analysis.

    The main conclusion is that the medical quality systems have been imbedded in the political management alongside the development towards a public knowledge management. The analysis has more specifically uncovered that quality registries in healthcare have been influenced by political ideologies, management ideas and ideas of transparency. It is also clear that open comparisons were an ‘unintended consequence’ of the quality registry development that has enhanced the development towards a public knowledge management.

    The analysis also shows that public knowledge management challenges the ideal of democratic enlightened understanding. The development of public knowledge management in the healthcare sector raises the question of who is governing whom in Swedish healthcare.

    List of papers
    1. Explaining Quality Management in the Danish and Swedish Public Health Sectors: Unintended Learning and Deliberate Co-Optation
    Open this publication in new window or tab >>Explaining Quality Management in the Danish and Swedish Public Health Sectors: Unintended Learning and Deliberate Co-Optation
    2016 (English)In: International Journal of Public Administration, ISSN 0190-0692, E-ISSN 1532-4265, Vol. 39, no 12, p. 963-975Article in journal (Refereed) Published
    Abstract [en]

    This article examines the development of diverse quality systems in the otherwise quite similar Danish and Swedish public health sectors. After decades of numerous piecemeal medical and managerial quality development programs in both countries, a nationwide mandatory accreditation system was introduced in the Danish health services in 2009. Nationwide quality indicator projects are also found in Sweden, but there has been political attempt to introduce a compulsory system. This article seeks to explain this difference. It argues, first, that resistance from the medical professions blocked the introduction of compulsory, nationwide quality systems in both countries for decades. Second, the implementation of the Danish accreditation system was triggered by a combination of unintended policy learning produced by local reforms in two counties and of the Ministry of Health’s carefully orchestrated policy process that served to co-opt critical voices in the medical profession.

    Place, publisher, year, edition, pages
    Routledge, 2016
    Keywords
    Historical institutionalism; path dependency; policy learning; quality managment systems
    National Category
    Public Administration Studies
    Identifiers
    urn:nbn:se:liu:diva-128223 (URN)10.1080/01900692.2015.1064959 (DOI)2-s2.0-84958530409 (Scopus ID)
    Available from: 2016-05-23 Created: 2016-05-23 Last updated: 2017-11-30Bibliographically approved
    2. What frames Quality Registers in Swedish Health Care: an institutional approach
    Open this publication in new window or tab >>What frames Quality Registers in Swedish Health Care: an institutional approach
    2011 (English)In: Proceedings from 14th Uddevalla Symposium, 2011 Entrepreneurial Knowledge, Technology and Transformation of Regions / [ed] Iréne Bernhard, Linköping: Linköping University Electronic Press, 2011, p. 1-19Conference paper, Published paper (Other academic)
    Abstract [en]

    Quality issues strike the classical conflict in a democratic health-care deliverysystem of different interests among the politicians, the medical profession andpublic officials. This cannot be studied as a cut-off whiz. Quality registers havedeveloped over the past 40 years. Therefore, this paper puts the innovation ofquality registers in an institutional perspective. Two things are essential in thispaper. First, this paper reviews the emergence of quality registers in Swedish healthcare as an effect of institutional arrangements. Second, it analyses the interactionof diverse factors in different institutional settings and logics. The relevant data forthe study was collected from official/unofficial policy documents and key actorinterviews.The empirical findings show that three different waves of development can betraced in history that has highly affected the development of quality registers. Italso shows that medical quality is framed and determined by physicians in line withprofessional knowledge and by the primary institutional logic of quality in medicalcare. However, organisational quality in health care is framed by the logic ofpublic equity of access based on a third party payer and the logic of managerialcontrol. These two paths of quality developments are now federating in aninstitutional logic of transparency. The contribution of this paper is importantbecause it produces insights in different institutional logics, which frames the riseof the two quality paths and the problems they have to face in order to merge. It also enhances the existing knowledge that institutions matter.

    Place, publisher, year, edition, pages
    Linköping: Linköping University Electronic Press, 2011
    Series
    Research Reports 2011:05 University West, ISSN 1653-7831 ; 2011:05
    Keywords
    health care, institutional change, quality, innovation
    National Category
    Public Administration Studies
    Identifiers
    urn:nbn:se:liu:diva-88746 (URN)978-91-977943-2-9 (ISBN)
    Conference
    14th Uddevalla Symposium, 2011 Entrepreneurial Knowledge, Technology and Transformation of Regions, June 16-18, Bergamo, Italy
    Available from: 2013-02-19 Created: 2013-02-18 Last updated: 2016-08-31Bibliographically approved
    3. Path Dependence on New Roads. Institutional Development of Quality Registers
    Open this publication in new window or tab >>Path Dependence on New Roads. Institutional Development of Quality Registers
    2014 (English)In: Offentlig Förvaltning. Scandinavian Journal of Public Administration, ISSN 2000-8058, E-ISSN 2001-3310, Vol. 18, no 2, p. 3-22Article in journal (Refereed) Published
    Abstract [en]

    When explaining social development and changes in public administration, institutional changeis a typical focus. Institutional analysis can combine the analyses of changes on the basis offormal legal and informal arrangements; it commonly shows that institutions lead to inertiawhere changes over time are concerned. Political aims are a guide to how organizations aredesigned and governed. When goals and earlier decisions clearly guide change, path dependenceis a fundamental concept when explaining change. However, this analysis shows how andwhen quality registers appeared as an answer to changes in institutional arrangements in Swedishpublic healthcare. Through three phases, cumulative processes have been visible and theprocesses have been followed by an improved and increased usage of quality registers andother quality systems. This analysis shows that institutional development can be pathdependentin relation to methods and means. Despite changing goals over time, quality registersas a policy tool have been path-dependent and stayed firm. Thus, it is important to see alsoorganisational methods as a development path that can be used to implement even new policyaims.

    Place, publisher, year, edition, pages
    Förlag Göteborgs Universitet, 2014
    Keywords
    Institutional change, quality registers, public governance, path dependence, time
    National Category
    Public Administration Studies
    Identifiers
    urn:nbn:se:liu:diva-114514 (URN)
    Available from: 2015-02-25 Created: 2015-02-25 Last updated: 2018-06-15Bibliographically approved
    4. Policymaking through healthcare registries in Sweden
    Open this publication in new window or tab >>Policymaking through healthcare registries in Sweden
    2018 (English)In: Health Promotion International, ISSN 0957-4824, E-ISSN 1460-2245, Vol. 33, no 2, p. 356-365Article in journal (Refereed) Published
    Abstract [en]

    Healthcare registries, otherwise known in Sweden as national quality registries (NQRs), have progressed from being a patient-focused system supporting medical results to become the basis of a health policy steering instrument called regional comparisons (RCs). This article seeks to explain RCs as an unintended consequence of the NQR development, by utilizing the concepts of policy entrepreneurs and streams of impact: the problem stream (problem perceived), the policy stream (what is valid), and the political stream (governmental objectives). The empirical contribution lies in insights on how the RCs have developed as an unintended consequence of entrepreneurial deliberate action in the process of creating NQRs. These findings are based on documents, interviews, and previous research in the social sciences. The article also argues for a critical understanding of public knowledge management (PKM) related to experiences in the development of NQRs regarding how to use knowledge in healthcare government. This article highlights how knowledge generated in quality systems based on registries could imply a stronger role for authorities in exerting control over the medical profession. It also discusses the potential use of research evidence on NQRs as a base for more efficient policymaking.

    Place, publisher, year, edition, pages
    Oxford University Press, 2018
    Keywords
    quality registries, stream coupling, policy entrepreneurs, public knowledge management
    National Category
    Political Science
    Identifiers
    urn:nbn:se:liu:diva-131037 (URN)10.1093/heapro/daw064 (DOI)000429490000018 ()27594141 (PubMedID)
    Available from: 2016-09-06 Created: 2016-09-06 Last updated: 2018-04-26Bibliographically approved
    5. Public quality – for whom and how?: Integrating public core values with quality management
    Open this publication in new window or tab >>Public quality – for whom and how?: Integrating public core values with quality management
    2017 (English)In: Total quality management and business excellence (Online), ISSN 1478-3363, E-ISSN 1478-3371, Vol. 28, no 3-4, p. 379-389Article in journal (Refereed) Published
    Abstract [en]

    Quality management (QM) plays an important role in public organisations’ efforts to create better access to, and effectiveness of, specific services. When transferring QM models from market-based firms to public services provided by public organisations, several basic contrasts and even contradictions must be addressed. Core values of the public sector differ from those of the private sector, but what are the consequences of this distinction? In this article we discuss the importance of four central arguments on public services: rights and access have to be considered; equality is an important facet of public services; coerciveness is a unique feature of public services; and legitimacy can be improved by high-quality services. These arguments have not been discussed explicitly in the context of QM. Adding these central aspects of public services to the QM field could generate more sustainable ways for developing quality and QM in public services in particular and the public sector in general.

    Place, publisher, year, edition, pages
    Routledge, 2017
    Keywords
    public sector; customer; citizen; quality management
    National Category
    Public Administration Studies
    Identifiers
    urn:nbn:se:liu:diva-128224 (URN)10.1080/14783363.2015.1087841 (DOI)000397039800010 ()2-s2.0-84945236799 (Scopus ID)
    Available from: 2016-05-23 Created: 2016-05-23 Last updated: 2018-06-15Bibliographically approved
  • 101013.
    Örnerheim, Mattias
    Linköping University, Department of Management and Engineering, Political Science. Linköping University, Faculty of Arts and Sciences.
    Policymaking through healthcare registries in Sweden2018In: Health Promotion International, ISSN 0957-4824, E-ISSN 1460-2245, Vol. 33, no 2, p. 356-365Article in journal (Refereed)
    Abstract [en]

    Healthcare registries, otherwise known in Sweden as national quality registries (NQRs), have progressed from being a patient-focused system supporting medical results to become the basis of a health policy steering instrument called regional comparisons (RCs). This article seeks to explain RCs as an unintended consequence of the NQR development, by utilizing the concepts of policy entrepreneurs and streams of impact: the problem stream (problem perceived), the policy stream (what is valid), and the political stream (governmental objectives). The empirical contribution lies in insights on how the RCs have developed as an unintended consequence of entrepreneurial deliberate action in the process of creating NQRs. These findings are based on documents, interviews, and previous research in the social sciences. The article also argues for a critical understanding of public knowledge management (PKM) related to experiences in the development of NQRs regarding how to use knowledge in healthcare government. This article highlights how knowledge generated in quality systems based on registries could imply a stronger role for authorities in exerting control over the medical profession. It also discusses the potential use of research evidence on NQRs as a base for more efficient policymaking.

  • 101014.
    Örnerheim, Mattias
    Linköping University, Department of Management and Engineering, Political Science. Linköping University, Faculty of Arts and Sciences.
    What frames Quality Registers in Swedish Health Care: an institutional approach2011In: Proceedings from 14th Uddevalla Symposium, 2011 Entrepreneurial Knowledge, Technology and Transformation of Regions / [ed] Iréne Bernhard, Linköping: Linköping University Electronic Press, 2011, p. 1-19Conference paper (Other academic)
    Abstract [en]

    Quality issues strike the classical conflict in a democratic health-care deliverysystem of different interests among the politicians, the medical profession andpublic officials. This cannot be studied as a cut-off whiz. Quality registers havedeveloped over the past 40 years. Therefore, this paper puts the innovation ofquality registers in an institutional perspective. Two things are essential in thispaper. First, this paper reviews the emergence of quality registers in Swedish healthcare as an effect of institutional arrangements. Second, it analyses the interactionof diverse factors in different institutional settings and logics. The relevant data forthe study was collected from official/unofficial policy documents and key actorinterviews.The empirical findings show that three different waves of development can betraced in history that has highly affected the development of quality registers. Italso shows that medical quality is framed and determined by physicians in line withprofessional knowledge and by the primary institutional logic of quality in medicalcare. However, organisational quality in health care is framed by the logic ofpublic equity of access based on a third party payer and the logic of managerialcontrol. These two paths of quality developments are now federating in aninstitutional logic of transparency. The contribution of this paper is importantbecause it produces insights in different institutional logics, which frames the riseof the two quality paths and the problems they have to face in order to merge. It also enhances the existing knowledge that institutions matter.

  • 101015.
    Örnerheim, Mattias
    et al.
    Linköping University, Department of Management and Engineering, Political Science. Linköping University, Faculty of Arts and Sciences.
    Elg, Mattias
    Linköping University, Department of Management and Engineering, Logistics & Quality Management. Linköping University, Faculty of Science & Engineering.
    Implementering i vården: En kunskapsöversikt om beslutsnivåer och professionsperspektiv2018Report (Other academic)
    Abstract [sv]

    Hälso- och sjukvården liksom socialtjänsten är under ständig förändring – medicinska framsteg skapar nya möjligheter till behandling samtidigt som behoven av hälso- och sjukvård och socialtjänst ökar i takt med att allt fler lever längre med kroniska sjukdomar. Socialtjänsten kommer att behöva stödja fler med långvariga och komplexa behov, vilket band annat kommer att ställa krav på ändrade arbetssätt. En fortsatt utveckling i vården och omsorgen är viktigt för att i dag och i framtiden kunna tillhandahålla en god vård och omsorg som patienter och brukare känner förtroende för.Samtidigt finns tecken på att utvecklingen och lärandet inte sker i den omfattning som behövs. I olika analyser har Vårdanalys genom åren visat att lärandet mellan olika verksamheter och huvudmän är begränsat. Orsakerna bakom det är flera.Hösten 2017 initierade vi ett forskningsuppdrag med ambitionen att utifrån litteraturen identifiera övergripande utmaningar när det gäller implementering i hälso- och sjukvården och socialtjänsten. Vi gav professor Mattias Elg och postdoktor Mattias Örnerheim vid institutionen för ekonomisk och industriell utveckling (IEI), Linköpings universitet, uppdraget att presentera en kunskapsöversikt på detta tema.Deras översikt har varit ett värdefullt bidrag till Vårdanalys arbeten under 2017 och 2018 som på olika sätt analyserat utvecklingsarbete och deras förutsättningar att bidra till långsiktig utveckling. Det är vår förhoppning att den här promemorian kan tjäna som ett kunskapsunderlag i den fortsatta diskussionen om hur vi kan skapa bättre förutsättningar till lärande och utveckling i vården och omsorgen.Den här promemorian är författarnas redovisning av forskningsuppdraget i sin helhet och de står själva för innehållet.

  • 101016.
    Örnerheim, Mattias
    et al.
    Linköping University, Department of Management and Engineering, Political Science. Linköping University, Faculty of Arts and Sciences.
    Triantafilloub, Peter
    Department of Society and Globalisation, Roskilde University,Roskilde, Denmark.
    Explaining Quality Management in the Danish and Swedish Public Health Sectors: Unintended Learning and Deliberate Co-Optation2016In: International Journal of Public Administration, ISSN 0190-0692, E-ISSN 1532-4265, Vol. 39, no 12, p. 963-975Article in journal (Refereed)
    Abstract [en]

    This article examines the development of diverse quality systems in the otherwise quite similar Danish and Swedish public health sectors. After decades of numerous piecemeal medical and managerial quality development programs in both countries, a nationwide mandatory accreditation system was introduced in the Danish health services in 2009. Nationwide quality indicator projects are also found in Sweden, but there has been political attempt to introduce a compulsory system. This article seeks to explain this difference. It argues, first, that resistance from the medical professions blocked the introduction of compulsory, nationwide quality systems in both countries for decades. Second, the implementation of the Danish accreditation system was triggered by a combination of unintended policy learning produced by local reforms in two counties and of the Ministry of Health’s carefully orchestrated policy process that served to co-opt critical voices in the medical profession.

  • 101017.
    Örnerheim, Mattias
    et al.
    Linköping University, Department of Management and Engineering, Political Science. Linköping University, Faculty of Arts and Sciences.
    Wihlborg, Elin
    Linköping University, Department of Management and Engineering, Political Science. Linköping University, Faculty of Arts and Sciences.
    Path Dependence on New Roads. Institutional Development of Quality Registers2014In: Offentlig Förvaltning. Scandinavian Journal of Public Administration, ISSN 2000-8058, E-ISSN 2001-3310, Vol. 18, no 2, p. 3-22Article in journal (Refereed)
    Abstract [en]

    When explaining social development and changes in public administration, institutional changeis a typical focus. Institutional analysis can combine the analyses of changes on the basis offormal legal and informal arrangements; it commonly shows that institutions lead to inertiawhere changes over time are concerned. Political aims are a guide to how organizations aredesigned and governed. When goals and earlier decisions clearly guide change, path dependenceis a fundamental concept when explaining change. However, this analysis shows how andwhen quality registers appeared as an answer to changes in institutional arrangements in Swedishpublic healthcare. Through three phases, cumulative processes have been visible and theprocesses have been followed by an improved and increased usage of quality registers andother quality systems. This analysis shows that institutional development can be pathdependentin relation to methods and means. Despite changing goals over time, quality registersas a policy tool have been path-dependent and stayed firm. Thus, it is important to see alsoorganisational methods as a development path that can be used to implement even new policyaims.

  • 101018.
    Örtegren, Hanna
    et al.
    Linköping University, Department of Behavioural Sciences and Learning, Work and Working Life.
    Wahlberg, Ellinor
    Linköping University, Department of Behavioural Sciences and Learning, Work and Working Life. Linköping University, Department of Behavioural Sciences and Learning, Education and Sociology.
    Att arbeta i ett aktivitetsbaserat kontor - givande eller påfrestande?: En kvalitativ studie om hur anställda upplever det aktivitetsbaserade kontoret och dess implementering.2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Bakgrund och syfte:Arbetet i ett aktivitetsbaserat kontor innebär både utmaningar och möjligheter. Syftet med studien är därför att undersöka vilka dessa är genom att studera hur ett företag som implementerat konceptet genomförde införandet, vilka effekter konceptet medfört samt huruvida arbetssättet tillgodoser den enskilde medarbetarens behov.

    Metod:Studien grundas i en kvalitativ metod och semistrukturerade intervjuer genomförda på ett fastighetsbolag som implementerat konceptet. Empirin har sedan analyserats och diskuterats i relation till forskning och teori inom aktuellt området.

    Resultat:Resultatet visar att implementeringsprocessen har stor inverkan på hur konceptet upplevs och används efter införandet samt att både kunskaps- och informationsflödet påverkats positivt. Resultatet visar på utmaningar gällande koncentration och avskildhet, vilket lett till vissa justeringar.

    Slutsatser:Viktiga slutsatser är betydelsen av att i ett tidigt skede av processen involvera medarbetarna i den förändring som arbetssättet innebär samt att konceptet kan ha en positiv inverkan på kunskaps- och informationsspridningen samt sammanhållningen.

  • 101019.
    Örtegren, Jonas
    et al.
    Department of Polymer Technology, Royal Institute of Technology, Stockholm, Sweden.
    Andersson, Gunnar
    Physics Department, Chalmers University of Technology, Göteborg, Sweden.
    Busson, Philippe
    Department of Polymer Technology, Royal Institute of Technology, Stockholm, Sweden.
    Hult, Anders
    Department of Polymer Technology, Royal Institute of Technology, Stockholm, Sweden.
    Gedde, Ulf W.
    Department of Polymer Technology, Royal Institute of Technology, Stockholm, Sweden.
    Eriksson, Anders
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, Faculty of Health Sciences.
    Lindgren, Mikael
    National Defence Research Establishment, Linköping, Sweden.
    Improved thermal stability of pyroelectric polymers by crosslinking of ferroelectric liquid crystals2001In: Journal of Physical Chemistry B, ISSN 1520-6106, E-ISSN 1520-5207, Vol. 105, no 42, p. 10223-10227Article in journal (Refereed)
    Abstract [en]

    Monofunctional ferroelectric liquid crystalline monomers and a blend of monofunctional/bifunctional ferroelectric liquid crystalline monomers were photopolymerized, yielding a side-chain liquid crystalline polymer and a cross-linked polymer, respectively. The cross-linked polymer exhibited higher thermal stability than the side-chain liquid crystalline polymer and was pyroelectric up to 170 °C, whereas the side-chain liquid crystalline polymer lost most of its pyroelectricity at 38 °C. It is shown by electrooptic and birefringence measurements that cross-linking in the unwound SmC* phase prevented the reoccurrence of the helical superstructure.

  • 101020.
    Örtegren, Jonas
    et al.
    Department of Polymer Technology, Royal Institute of Technology, Sweden.
    Busson, Philippe
    Department of Polymer Technology, Royal Institute of Technology, Sweden.
    Gedde, Ulf W.
    Department of Polymer Technology, Royal Institute of Technology, Sweden.
    Hult, Anders
    Department of Polymer Technology, Royal Institute of Technology, Sweden.
    Eriksson, Anders
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology.
    Lindgren, Mikael
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology.
    Andersson, Gunnas
    Physics Department, Chalmers University of Technology, Göteborg, Sweden.
    Cone motion viscosity and optical second harmonic generation of ferroelectric liquid crystalline dendrimers2001In: Liquid crystals (Print), ISSN 0267-8292, E-ISSN 1366-5855, Vol. 28, no 6, p. 861-868Article in journal (Refereed)
    Abstract [en]

    We report second harmonic generation in a ferroelectric liquid crystalline trimer and ferroelectric liquid crystalline dendrimers of first, second and third generation. Thin cells were filled with the compounds by capillary forces at elevated temperature, and cooled from the surface stabilized ferroelectric state to below the glass transition temperature, while kept in an electric field. The cone motion viscosity and the threshold electric field for unwinding of the helix axis of the chiral tilted smectic mesophases were studied separately at elevated temperature, and these data were used to optimize the preparation of the films. The measured response time was between 0.3 and 3ms, which corresponds to a cone motion viscosity between 0.5 and 50 Pa s. Second harmonic generation was studied both at elevated temperature with an electric field and at room temperature with and without electric field. The first generation dendrimer exhibited a strong increase in the second order non-linear optical response with time at room temperature. The d 23-coefficient of this dendrimer was approximately four times larger than for the other macromolecules and was 0.045 pm V-1. The relatively large d-coefficient of the first generation dendrimer is ascribed to crystallization, which improved the orientation of the molecular dipoles.

  • 101021.
    Örtegren, Jonas
    et al.
    Department of Polymer Technology, Royal Institute of Technology, Sweden.
    Busson, Philippe
    Department of Polymer Technology, Royal Institute of Technology, Sweden.
    Gedde, Ulf W.
    Department of Polymer Technology, Royal Institute of Technology, Sweden.
    Hult, Anders
    Department of Polymer Technology, Royal Institute of Technology, Sweden.
    Eriksson, Anders
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology.
    Lindgren, Mikael
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology.
    Arntzén, Per-Otto
    National Defence Research Establishment, Linköping, Sweden.
    Hermann, David S.
    Physics Department, Chalmers University of Technology,Göteborg, Sweden.
    Rudquist, Per
    Physics Department, Chalmers University of Technology,Göteborg, Sweden.
    Lagerwall, Sven T.
    Physics Department, Chalmers University of Technology,Göteborg, Sweden.
    Time-dependent nonlinear optical properties of pyroelectric liquid crystalline polymers1999In: Macromolecular Symposia, ISSN 1022-1360, E-ISSN 1521-3900, Vol. 148, p. 179-195Article in journal (Refereed)
    Abstract [en]

    Highly oriented pyroelectric liquid-crystalline polymers were prepared by photopolymerization under the influence of a static electric field from binary mixtures of two acrylate monomers exhibiting chiral smectic C mesomorphism. Both monomers contained nitro groups to yield second order nonlinear optical properties (second harmonic generation) and one of the monomers had two functional groups to yield a crosslinked polymer. The room temperature second order nonlinear susceptibility of the polymers showed during the first two hours a 10 % decrease after which it remained constant during the next 48 days. At elevated temperatures there was a significant difference in the nonlinear optical properties over time between crosslinked and uncrosslinked polymers. The uncrosslinked polymer showed a pronounced loss of second order nonlinear optical activity with time at ≥38°C. The crosslinked polymer showed a much smaller and basically a temperature independent decrease rate in the second order nonlinear optical properties at all the ageing temperatures (23-130°C). Both the loss in mesogen order parameter, very evident for the uncrosslinked polymer, and conformational changes occurring within the mesogens (β mechanism), may account for the observations made.

  • 101022.
    Örtegren Kugelberg, Unn
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Central adipocyte functions in specialized caveolae2006Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Obesity and overweight is an increasing health problem in the world. Besides reducing quality of life obesity is a great risk factor for development of diseases such as type 2 diabetes, cardiovascular disease, and stroke. The adipose tissue is a flexible organ that grows in size if the body is provided with excess energy. Adipocytes store the excess energy in the form of triacylglycerol. The incorporation of fat is stimulated by insulin, while catecholamines promote hydrolysis of triacylglycerol. In the membrane of adipocytes there are cave-like invaginations, caveolae, where proteins involved in insulin signalling, such as the insulin receptor are located. The focus of this thesis is on the function, and thereby the importance, of adipocytes and caveolae in metabolism.

    The lipid content of the plasma membrane and caveolae was analyzed and compared to lipid phases determined in model membranes. The amount of different membrane lipids indicated heterogeneity of the caveolae, since there were not enough of some specific molecules to be present in every caveola. Using density gradient ultra centrifugation three different subclasses of caveolae were identified. These subclasses were named according to their relative densities: very high density caveolae, high density caveolae and low density caveolae. There were clear differences between the classes with regard to the distribution of specific proteins in them. In low density caveolae proteins linked to cholesterol metabolism, scavenger receptor class B type I and CD36, were abundant. Proteins involved in fatty acid metabolism, fatty acid transporter protein 1 and 4, acyl CoA-syntethase, perilipin and hormone sensitive lipase, were localized to high density caveolae. Cholesteryl ester uptake from HDL particles and hydrolysis to cholesterol was found in low density caveolae and the uptake of fatty acids was restricted to high density caveolae. Remarkably, the fatty acids were not only taken up via high density caveolae, but also incorporated into triacylglycerol, diacylglycerol, and phosphatidylcholine. This indicates that the whole machinery for lipid synthesis is located in these caveolae.

    In addition to being an energy store the adipose tissue is also an endocrine organ. Several of the secreted proteins affect the metabolism of the body, for instance adiponectin that affects insulin sensitivity. Here adiponectin was located at the plasma membrane to the caveolae, both by biochemical isolation of caveolae and by electron microscopy. Together with earlier findings this indicates that caveolae may be involved in the secretion of adiponectin.

    In conclusion, caveolae are involved in central processes such as glucose metabolism and signalling. Herein it is shown that caveolae is involved in the metabolism of fatty acids and cholesterol and may also be involved in the secretion of the metabolic hormone adiponectin. The findings in this thesis together with previous research establish caveolae as metabolic platforms.

    List of papers
    1. Lipids and glycosphingolipids in caveolae and surrounding plasma membrane of primary rat adipocytes
    Open this publication in new window or tab >>Lipids and glycosphingolipids in caveolae and surrounding plasma membrane of primary rat adipocytes
    Show others...
    2004 (English)In: European Journal of Biochemistry, ISSN 0014-2956, E-ISSN 1432-1033, Vol. 271, no 10, p. 2028-2036Article in journal (Refereed) Published
    Abstract [en]

    We have made a comprehensive and quantitative analysis of the lipid composition of caveolae from primary rat fat cells and compared the composition of plasma membrane inside and outside caveolae. We isolated caveolae from purified plasma membranes using ultrasonication in carbonate buffer to disrupt the membrane, or extraction with nonionic detergent, followed by density gradient ultracentrifugation. The carbonate-isolated caveolae fraction was further immunopurified using caveolin antibodies. Carbonate-isolated caveolae were enriched in cholesterol and sphingomyelin, and the concentration was three- and twofold higher, respectively, in caveolae compared to the surrounding plasma membrane. The concentration of glycerophospholipids was similar suggesting that glycerophospholipids constitute a constant core throughout the plasma membrane. The composition of detergent-insoluble fractions of the plasma membrane was very variable between preparations, but strongly enriched in sphingomyelin and depleted of glycerophospholipids compared to carbonate-isolated caveolae; indicating that detergent extraction is not a suitable technique for caveolae preparation. An average adipocyte caveola contained about 22 × 103 molecules of cholesterol, 7.5 × 103 of sphingomyelin and 23 × 103 of glycerophospholipid. The glycosphingolipid GD3 was highly enriched in caveolae, whereas GM3, GM1 and GD1a were present inside as well as outside the caveolae membrane. GD1b, GT1b, GM2, GQ1b, sulfatide and lactosylceramide sulfate were not detected in caveolae.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-22409 (URN)10.1111/j.1432-1033.2004.04117.x (DOI)1621 (Local ID)1621 (Archive number)1621 (OAI)
    Available from: 2009-10-07 Created: 2009-10-07 Last updated: 2017-12-13Bibliographically approved
    2. Triacylglycerol is synthesized in a specific subclass of caveolae in primary adipocytes
    Open this publication in new window or tab >>Triacylglycerol is synthesized in a specific subclass of caveolae in primary adipocytes
    Show others...
    2005 (English)In: Journal of Biological Chemistry, ISSN 0021-9258, E-ISSN 1083-351X, Vol. 280, no 1, p. 5-8Article in journal (Refereed) Published
    Abstract [en]

    A principal metabolic function of adipocytes is to synthesize triacylglycerol (TG) from exogenous fatty acids. The level of fatty acids has to be tightly controlled in the adipocyte, as they can act as detergents that rapidly dissolve the plasma membrane, causing cell lysis if allowed to accumulate. Fatty acids therefore have to be efficiently converted to TG and stored in the central lipid droplet. We report that in intact primary adipocytes exogenous oleic acid was taken up and directly converted to TG in the plasma membrane, in a novel subclass of caveolae that specifically contains the protein perilipin. Isolated caveolae catalyzed de novo TG synthesis from oleic acid and glycerol 3-phosphate. Electron microscopy revealed the presence of caveolin and perilipin in caveolae and in lipid-laden bulbs in the plasma membrane, and fluorescence microscopy demonstrated colocalization of fatty acids/TG with caveolin and perilipin at the plasma membrane. A second caveolae fraction was isolated, which lacked perilipin and the triacylglycerol synthesizing enzymes. Both caveolae fractions contained caveolin-1 and the insulin receptor. The findings demonstrate that specific subclasses of caveolae carry out specific functions in cell metabolism. In particular, triacylglycerol is synthesized at the site of fatty acid entry in one of these caveolae classes.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-20650 (URN)10.1074/jbc.C400429200 (DOI)15537657 (PubMedID)
    Available from: 2009-09-16 Created: 2009-09-16 Last updated: 2017-12-13Bibliographically approved
    3. Separation and characterization of caveolae subclasses in the plasma membrane of primary adipocytes: segregation of specific proteins and functions
    Open this publication in new window or tab >>Separation and characterization of caveolae subclasses in the plasma membrane of primary adipocytes: segregation of specific proteins and functions
    Show others...
    2006 (English)In: The FEBS Journal, ISSN 1742-464X, E-ISSN 1742-4658, Vol. 273, no 14, p. 3381-3392Article in journal (Refereed) Published
    Abstract [en]

    Caveolae are nearly ubiquitous plasma membrane domains that in adipocytes vary in size between 25 and 150 nm. They constitute sites of entry into the cell as well as platforms for cell signalling. We have previously reported that plasma membrane-associated caveolae that lack cell surface access can be identified by electron microscopy. We now report the identification, after density gradient ultracentrifugation, of a subclass of very high-density apparently closed caveolae that were not labelled by cell surface protein labelling of intact cells. These caveolae contained caveolin-1 and caveolin-2. Another class of high-density caveolae contained caveolin-1, caveolin-2 and specifically fatty acid transport protein-1, fatty acid transport protein-4, fatty acyl-CoA synthetase, hormone-sensitive lipase, perilipin, and insulin-regulated glucose transporter-4. This class of caveolae was specialized in fatty acid uptake and conversion to triacylglycerol. A third class of low-density caveolae contained the insulin receptor, class B scavenger receptor-1, and insulin-regulated glucose transporter-4. Small amounts of these proteins were also detected in the high-density caveolae. In response to insulin, the insulin receptor autophosphorylation and the amount of insulin-regulated glucose transporter-4 increased in these caveolae. The molar ratio of cholesterol to phospholipid in the three caveolae classes varied considerably, from 0.4 in very high-density caveolae to 0.9 in low-density caveolae. There was no correlation between the caveolar contents of caveolin and cholesterol. The low-density caveolae, with the highest cholesterol concentration, were particularly enriched with the cholesterol-rich lipoprotein receptor class B scavenger receptor-1, which mediated cholesteryl ester uptake from high-density lipoprotein and generation of free cholesterol in these caveolae, suggesting a specific role in cholesterol uptake/metabolism. These findings demonstrate a segregation of functions in caveolae subclasses.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-35681 (URN)10.1111/j.1742-4658.2006.05345.x (DOI)28128 (Local ID)28128 (Archive number)28128 (OAI)
    Available from: 2009-10-10 Created: 2009-10-10 Last updated: 2017-12-13Bibliographically approved
    4. Localization of adiponectin at the plasma membrane in caveolae of human adipocytes
    Open this publication in new window or tab >>Localization of adiponectin at the plasma membrane in caveolae of human adipocytes
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    The hormone adiponectin is exclusively secreted by adipocytes and it regulates whole body energy homeostasis primarily by affecting liver and muscles. The circulating level of adiponectin inversely correlates with insulin resistance and type 2 diabetes. Little is known about the secretion of adiponectin by the adipocyte, but in caveolin-1 knockout mice the amount of secreted adiponectin is severely reduced. Here we show that in human adipocytes adiponectin was associated with the plasma membrane and to a specific class of high-density-caveolae. Substantial amounts of adiponectin were also found in the microsomal and cytosolic fractions of adipocytes, while very little was associated with mitochondria, nuclei, or the fat. Adiponectin in isolated caveolae was readily degraded by added trypsin, demonstrating that adiponectin was largely bound to the cytosolic face of the caveolae membrane. The findings indicate that caveolae may have a critical role in the secretion of adiponectin by human adipocytes.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-84835 (URN)
    Available from: 2012-10-24 Created: 2012-10-24 Last updated: 2012-10-24Bibliographically approved
  • 101023.
    Örtegren Kugelberg, Unn
    et al.
    Linköping University, Department of Biomedicine and Surgery, Cell biology. Linköping University, Faculty of Health Sciences.
    Yin, Lan
    Linköping University, Department of Biomedicine and Surgery, Cell biology. Linköping University, Faculty of Health Sciences.
    Öst, Anita
    Linköping University, Department of Biomedicine and Surgery, Cell biology. Linköping University, Faculty of Health Sciences.
    Karlsson, Helen
    Linköping University, Department of Molecular and Clinical Medicine, Occupational and Environmental Medicine. Linköping University, Faculty of Health Sciences.
    Nyström, Fredrik
    Linköping University, Department of Medicine and Care, Internal Medicine. Linköping University, Faculty of Health Sciences.
    Strålfors, Peter
    Linköping University, Department of Biomedicine and Surgery, Cell biology. Linköping University, Faculty of Health Sciences.
    Separation and characterization of caveolae subclasses in the plasma membrane of primary adipocytes: segregation of specific proteins and functions2006In: The FEBS Journal, ISSN 1742-464X, E-ISSN 1742-4658, Vol. 273, no 14, p. 3381-3392Article in journal (Refereed)
    Abstract [en]

    Caveolae are nearly ubiquitous plasma membrane domains that in adipocytes vary in size between 25 and 150 nm. They constitute sites of entry into the cell as well as platforms for cell signalling. We have previously reported that plasma membrane-associated caveolae that lack cell surface access can be identified by electron microscopy. We now report the identification, after density gradient ultracentrifugation, of a subclass of very high-density apparently closed caveolae that were not labelled by cell surface protein labelling of intact cells. These caveolae contained caveolin-1 and caveolin-2. Another class of high-density caveolae contained caveolin-1, caveolin-2 and specifically fatty acid transport protein-1, fatty acid transport protein-4, fatty acyl-CoA synthetase, hormone-sensitive lipase, perilipin, and insulin-regulated glucose transporter-4. This class of caveolae was specialized in fatty acid uptake and conversion to triacylglycerol. A third class of low-density caveolae contained the insulin receptor, class B scavenger receptor-1, and insulin-regulated glucose transporter-4. Small amounts of these proteins were also detected in the high-density caveolae. In response to insulin, the insulin receptor autophosphorylation and the amount of insulin-regulated glucose transporter-4 increased in these caveolae. The molar ratio of cholesterol to phospholipid in the three caveolae classes varied considerably, from 0.4 in very high-density caveolae to 0.9 in low-density caveolae. There was no correlation between the caveolar contents of caveolin and cholesterol. The low-density caveolae, with the highest cholesterol concentration, were particularly enriched with the cholesterol-rich lipoprotein receptor class B scavenger receptor-1, which mediated cholesteryl ester uptake from high-density lipoprotein and generation of free cholesterol in these caveolae, suggesting a specific role in cholesterol uptake/metabolism. These findings demonstrate a segregation of functions in caveolae subclasses.

  • 101024.
    Örtegren, Unn
    et al.
    Linköping University, Department of Biomedicine and Surgery, Cell biology. Linköping University, Faculty of Health Sciences.
    Aboulaich, Nabila
    Linköping University, Department of Biomedicine and Surgery, Cell biology. Linköping University, Faculty of Health Sciences.
    Öst, Anita
    Linköping University, Department of Biomedicine and Surgery, Cell biology. Linköping University, Faculty of Health Sciences.
    Strålfors, Peter
    Linköping University, Department of Biomedicine and Surgery, Cell biology. Linköping University, Faculty of Health Sciences.
    A new role for caveolae as metabolic platforms2007In: Trends in endocrinology and metabolism, ISSN 1043-2760, E-ISSN 1879-3061, Vol. 18, no 9, p. 344-349Article in journal (Refereed)
    Abstract [en]

    The plasma membrane of cells functions as a barrier to the environment. Caveolae are minute invaginations of the membrane that selectively carry out the exchange of information and materials with the environment, by functioning as organizers of signal transduction and through endocytosis. Recent findings of uptake of different metabolites and of lipid metabolism occurring in caveolae, point to a new general function of caveolae. As gateways for the uptake of nutrients across the plasma membrane, and as platforms for the metabolic conversion of nutrients, especially in adipocytes, caveolae are now emerging as active centers for many aspects of intermediary metabolism, with implications for our understanding of obesity, diabetes and other metabolic disorders.

  • 101025.
    Örtegren, Unn
    et al.
    Linköping University, Department of Biomedicine and Surgery, Cell biology. Linköping University, Faculty of Health Sciences.
    Karlsson, Margareta
    Linköping University, Department of Biomedicine and Surgery, Cell biology. Linköping University, Faculty of Health Sciences.
    Blazic, Natascha
    Department of Clinical Neuroscience, Sahlgrenska University Hospital/Mölndal, Göteborg University, Mölndal, Sweden.
    Blomqvist, Maria
    Department of Clinical Neuroscience, Sahlgrenska University Hospital/Mölndal, Göteborg University, Mölndal, Sweden.
    Nyström, Fredrik
    Linköping University, Department of Biomedicine and Surgery, Cell biology. Linköping University, Faculty of Health Sciences.
    Gustavsson, Johanna
    Linköping University, Department of Biomedicine and Surgery, Cell biology. Linköping University, Faculty of Health Sciences.
    Fredman, Pam
    Department of Clinical Neuroscience, Sahlgrenska University Hospital/Mölndal, Göteborg University, Mölndal, Sweden.
    Strålfors, Peter
    Linköping University, Department of Biomedicine and Surgery, Cell biology. Linköping University, Faculty of Health Sciences.
    Lipids and glycosphingolipids in caveolae and surrounding plasma membrane of primary rat adipocytes2004In: European Journal of Biochemistry, ISSN 0014-2956, E-ISSN 1432-1033, Vol. 271, no 10, p. 2028-2036Article in journal (Refereed)
    Abstract [en]

    We have made a comprehensive and quantitative analysis of the lipid composition of caveolae from primary rat fat cells and compared the composition of plasma membrane inside and outside caveolae. We isolated caveolae from purified plasma membranes using ultrasonication in carbonate buffer to disrupt the membrane, or extraction with nonionic detergent, followed by density gradient ultracentrifugation. The carbonate-isolated caveolae fraction was further immunopurified using caveolin antibodies. Carbonate-isolated caveolae were enriched in cholesterol and sphingomyelin, and the concentration was three- and twofold higher, respectively, in caveolae compared to the surrounding plasma membrane. The concentration of glycerophospholipids was similar suggesting that glycerophospholipids constitute a constant core throughout the plasma membrane. The composition of detergent-insoluble fractions of the plasma membrane was very variable between preparations, but strongly enriched in sphingomyelin and depleted of glycerophospholipids compared to carbonate-isolated caveolae; indicating that detergent extraction is not a suitable technique for caveolae preparation. An average adipocyte caveola contained about 22 × 103 molecules of cholesterol, 7.5 × 103 of sphingomyelin and 23 × 103 of glycerophospholipid. The glycosphingolipid GD3 was highly enriched in caveolae, whereas GM3, GM1 and GD1a were present inside as well as outside the caveolae membrane. GD1b, GT1b, GM2, GQ1b, sulfatide and lactosylceramide sulfate were not detected in caveolae.

  • 101026.
    Örtegren, Unn
    et al.
    Linköping University, Department of Biomedicine and Surgery, Cell biology. Linköping University, Faculty of Health Sciences.
    Scherer, Philipp
    Albert Einstein College of Medicine, New York, NY, USA.
    Strålfors, Peter
    Linköping University, Department of Biomedicine and Surgery, Cell biology. Linköping University, Faculty of Health Sciences.
    Localization of adiponectin at the plasma membrane in caveolae of human adipocytesManuscript (preprint) (Other academic)
    Abstract [en]

    The hormone adiponectin is exclusively secreted by adipocytes and it regulates whole body energy homeostasis primarily by affecting liver and muscles. The circulating level of adiponectin inversely correlates with insulin resistance and type 2 diabetes. Little is known about the secretion of adiponectin by the adipocyte, but in caveolin-1 knockout mice the amount of secreted adiponectin is severely reduced. Here we show that in human adipocytes adiponectin was associated with the plasma membrane and to a specific class of high-density-caveolae. Substantial amounts of adiponectin were also found in the microsomal and cytosolic fractions of adipocytes, while very little was associated with mitochondria, nuclei, or the fat. Adiponectin in isolated caveolae was readily degraded by added trypsin, demonstrating that adiponectin was largely bound to the cytosolic face of the caveolae membrane. The findings indicate that caveolae may have a critical role in the secretion of adiponectin by human adipocytes.

  • 101027.
    Örtenberg, Alexander
    Linköping University, Department of Electrical Engineering, Information Coding. Linköping University, Faculty of Science & Engineering.
    Parallelization of DIRA and CTmod Using OpenMP and OpenCL2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Parallelization is the answer to the ever-growing demands of computing power by taking advantage of multi-core processor technology and modern many-core graphics compute units. Multi-core CPUs and many-core GPUs have the potential to substantially reduce the execution time of a program but it is often a challenging task to ensure that all available hardware is utilized. OpenMP and OpenCL are two parallel programming frameworks that have been developed to allow programmers to focus on high-level parallelism rather than dealing with low-level thread creation and management. This thesis applies these frameworks to the area of computed tomography by parallelizing the image reconstruction algorithm DIRA and the photon transport simulation toolkit CTmod. DIRA is a model-based iterative reconstruction algorithm in dual-energy computed tomography, which has the potential to improve the accuracy of dose planning in radiation therapy. CTmod is a toolkit for simulating primary and scatter projections in computed tomography to optimize scanner design and image reconstruction algorithms. The results presented in this thesis show that parallelization combined with computational optimization substantially decreased execution times of these codes. For DIRA the execution time was reduced from two minutes to just eight seconds when using four iterations and a 16-core CPU so a speedup of 15 was achieved. CTmod produced similar results with a speedup of 14 when using a 16-core CPU. The results also showed that for these particular problems GPU computing was not the best solution.

  • 101028.
    Örtenberg, Alexander
    et al.
    Linköping University, Department of Medical and Health Sciences, Division of Radiological Sciences. Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Faculty of Medicine and Health Sciences.
    Magnusson, Maria
    Linköping University, Department of Electrical Engineering, Computer Vision. Linköping University, Department of Medical and Health Sciences, Division of Radiological Sciences. Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Faculty of Science & Engineering. Linköping University, Faculty of Medicine and Health Sciences.
    Sandborg, Michael
    Linköping University, Center for Medical Image Science and Visualization (CMIV). 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.
    Alm Carlsson, Gudrun
    Linköping University, Center for Medical Image Science and Visualization (CMIV). 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.
    Malusek, Alexandr
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Department of Medical and Health Sciences, Division of Radiological Sciences. Linköping University, Faculty of Medicine and Health Sciences.
    PARALLELISATION OF THE MODEL-BASED ITERATIVE RECONSTRUCTION ALGORITHM DIRA2016In: Radiation Protection Dosimetry, ISSN 0144-8420, E-ISSN 1742-3406, Vol. 169, no 1-4, p. 405-409Article in journal (Refereed)
    Abstract [en]

    New paradigms for parallel programming have been devised to simplify software development on multi-core processors and many-core graphical processing units (GPU). Despite their obvious benefits, the parallelisation of existing computer programs is not an easy task. In this work, the use of the Open Multiprocessing (OpenMP) and Open Computing Language (OpenCL) frameworks is considered for the parallelisation of the model-based iterative reconstruction algorithm DIRA with the aim to significantly shorten the code’s execution time. Selected routines were parallelised using OpenMP and OpenCL libraries; some routines were converted from MATLAB to C and optimised. Parallelisation of the code with the OpenMP was easy and resulted in an overall speedup of 15 on a 16-core computer. Parallelisation with OpenCL was more difficult owing to differences between the central processing unit and GPU architectures. The resulting speedup was substantially lower than the theoretical peak performance of the GPU; the cause was explained.

  • 101029.
    Örtengren, Malin
    et al.
    Linköping University, Department of Management and Engineering.
    Torstensson, Tobias
    Linköping University, Department of Management and Engineering.
    Box vs styck: Ett beslutsunderlag till Stadium AB gällande styckhantering i distributionslagret som alternativ till boxar2007Independent thesis Advanced level (degree of Magister), 20 points / 30 hpStudent thesis
    Abstract [en]

    Stadium AB is one of the largest sports retail chain in Sweden, which designs, buys and sells sports equipment and sports fashion. The range encompasses both leading brand products, such as Adidas and Nike, as well as Stadium's own brands, such as SOC, 4D and Everest. Within the fashion industry the customer demand varies with changes in fashion and season. This makes the industry very complex which results in high requirements on distribution to the stores to deliver the right number of products at right time to each store. The reason for this is to avoid reduced revenue caused by bargain sales or cost of lost sales.

    One way that Stadium uses to introduce and refill stores with products is with boxes. The boxes contain a predetermined number of a specific product, for example twenty red t-shirts. Using boxes makes it difficult to distribute the right product to the right store, which can increase bargain sales and costs of lost sales. A more accurate way to meet demand from the customers can be to replace the use of boxes with piece by piece handling. The purpose of the study is to provide Stadium with a decision basis of effects to the supply chain, in view of costs and delivery service, caused by piece by piece handling as an alternative to boxes.

    In order to fulfil the purpose of this thesis, delivery services and cost in the current distribution system induced by boxes were examined through interviews, time studies and analysis of historical data. Then changes in costs and delivery service induced by the use of piece by piece handling instead of boxes were studied.

    The conclusion of this study is not unambiguous, it results in an undefined ”it depends on…”. If Stadium should use boxes or pieces to distribute their products depends on the characteristics of the products. Three parameters that affect changes in costs when use piece by piece handling instead of boxes and are important to review are:

    - The number of sizes in a box.

    - The number of products in a box.

    - The volume of the product.

  • 101030.
    Örtnäs, Anna
    Linköping University, Department of Educational Science (IUV).
    Elevers vardagsuppfattningar om tekniska system2007Independent thesis Basic level (degree of Bachelor), 10 points / 15 hpStudent thesis
    Abstract [sv]

    Elever ska enligt kursplanerna i teknik få förståelse för de tekniska system de möter i sitt dagliga liv. Genom att eleverna får kunskap om teknik i allmänhet och tekniska system i synnerhet får de möjlighet att påverka sina liv som medborgare i en demokrati. I litteraturen saknas idag studier om elevers uppfattningar om tekniska system. Syftet med detta examensarbete är därför att studera vilka vardagsuppfattningar elever har om de tekniska system de möter i vardagen. Studien utgår från systemteori vilken ger en möjlighet att utnyttja det gemensamma mönster som kännetecknar analys av system. Genom enskilda intervjuer har jag studerat hur elever i år 8 och år 2 på gymnasiet uppfattar tekniska system, såsom mobiltelefonsystemet, tvättmaskinen och aluminiumburkens system. Vid intervjuerna användes tankestöttor, d v s föremål och bilder som anknyter till de tekniska systemen, vilket inspirerats av studier om begreppsuppfattning inom naturvetenskapen. Som ett komplement till samtalet uppmanades informanterna att skissa sin förståelse av systemen på papper. Resultaten visar att eleverna på högstadiet och gymnasiet har god kunskap om de tekniska systemen i denna studie. Informanterna har förmågan att se systemens struktur med delsystem. De visar kunskap om sambanden mellan människa och teknik och människans olika roller. Studien har givit mig värdefulla kunskaper om elevernas vardagsuppfattningar om tekniska system vilket ger mig möjlighet att lägga upp min framtida undervisning med utgångspunkt i deras konkreta erfarenheter av teknik i vardagen.

  • 101031.
    Örtqvist, Eva
    et al.
    Astrid Lindgrens Barnsjukhus Stockholm.
    Ludvigsson, Johnny
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Molecular and Clinical Medicine, Pediatrics. Östergötlands Läns Landsting, Centre of Paediatrics and Gynecology and Obstetrics, Department of Paediatrics in Linköping.
    Åman, Jan
    Barnkliniken Universitetssjukhuset, Örebro.
    Johansson, Calle
    Barnkliniken Ryhovs sjukhus, Jönköping.
    Karlsson, Anders
    Medicinkliniken Akademiska sjukhuset, Uppsala.
    Forsander, Gun
    Barnkliniken Lasarettet, Falun.
    Lindgren, Fredrik
    Sachsska Barnsjukhuset Stockholm.
    Persson, Bengt
    Astrid Lindgrens Barnsjukhus Stockholm.
    Berglund, Lars
    Clinical Research Centre Uppsala Universitet.
    Berne, Christian
    Medicinkliniken Akademiska sjukhuset, Uppsala.
    Bengtsson, Mats
    Klinisk Immunologi Uppsala Universitet.
    Björk, Elisabeth
    Medicinkliniken Akademiska sjukhuset, Uppsala.
    Wallensteen, Måna
    Astrid Lindgrens Barnsjukhus Stockholm.
    Temporary preservation of β-cell function by diazoxide treatment in childhood type 1 diabetes2004In: Diabetes Care, ISSN 0149-5992, E-ISSN 1935-5548, Vol. 27, no 9, p. 2191-2197Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE - We examined the effect of diazoxide, an ATP-sensitive K + channel opener and inhibitor of insulin secretion, on β-cell function and remission in children at clinical onset of type 1 diabetes. RESEARCH DESIGN AND METHODS - A total of 56 subjects (21 girls and 35 boys, age 7-17 years) were randomized to 3 months of active treatment (diazoxide 5-7.5 mg/kg in divided doses) or placebo in addition to multiple daily insulin injections and were followed for 2 years. RESULTS - Diazoxide decreased circulating C-peptide concentrations by ∼50%. After cessation of the treatment, basal and meal-stimulated C-peptide concentrations increased to a maximum at 6 months, followed by a decline. Meal-stimulated C-peptide concentration was significantly higher at 12 months (0.43 ± 0.22 vs. 0.31 ± 0.26 nmol/l, P = 0.018) and tended to fall less from clinical onset to 24 months in the diazoxide- vs. Placebo-treated patients (-0.05 ± 0.24 vs. -0.18 ± 0.26 nmol/l, P = 0.064). At 24 months, the meal-stimulated C-peptide concentrations were 0.24 ± 0.20 and 0.20 ± 0.17 nmol/l, respectively. Side effects of diazoxide were prevalent. CONCLUSIONS - This study demonstrates that partial inhibition of insulin secretion for 3 months at onset of childhood type 1 diabetes suspends the period of remission and temporarily preserves residual insulin production. Further evaluation of the full potential of β-cell rest will require compounds with less side effects as well as protocols optimized for sustained secretory arrest.

  • 101032.
    Örtqvist, Å.
    et al.
    Karolinska Institute, Danderyd Hospital, Stockholm, Sweden.
    Valtonen, M.
    University Central Hospital, Helsinki, Finland.
    Cars, O.
    Uppsala University, Sweden.
    Wahl, M.
    Östra Hospital, Göteborg University, Sweden.
    Saikku, P.
    University of Oulu and National Public Health Institute, Finland.
    Jean, C.
    Rhone DPC Europe, Paris, France.
    Augustinsson (Nilsdotter-Augustinsson), Åsa
    Linköping University, Department of Molecular and Clinical Medicine, Infectious Diseases. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Medicine, Department of Infectious Diseases in Östergötland.
    Oral empiric treatment of community-acquired pneumonia: A multicenter, double-blind, randomized study comparing sparfloxacin with roxithromycin. The Scandinavian Sparfloxacin Study Group1996In: Chest, ISSN 0012-3692, E-ISSN 1931-3543, Vol. 110, no 6, p. 1499-1506Article in journal (Refereed)
    Abstract [en]

    STUDY OBJECTIVE:

    Comparison of efficacy and safety of sparfloxacin (Spfx) vs roxithromycin (ROXI) for treatment of community-acquired pneumonia (CAP).

    DESIGN:

    Multicenter, double-blind, randomized study.

    SETTING:

    Twenty-three university and community hospitals in Scandinavia.

    PATIENTS:

    Three hundred four adults (> or = 18 years of age) with CAP treated as outpatients (25%) or inpatients (75%).

    INTERVENTIONS:

    Randomization 1:1 to Spfx, 400 mg on day 1, then 200 mg once daily, or ROXI, 150 mg twice daily, 10 to 14 days. Safety and efficacy analyses in intention-to-treat (ITT) and evaluable populations.

    RESULTS:

    Three hundred three of 304 patients were included in the ITT and safety analyses and 260 (86%) were evaluable at the end of follow-up. Streptococcus pneumoniae was the cause of pneumonia in 62 (20%) patients (11 with bacteremia), Chlamydia pneumoniae in 40 (13%), and Mycoplasma pneumoniae in 38 (13%) patients. The success rates for Spfx and ROXI at the end of follow-up were 82% and 72%, respectively, in the ITT population, and 94% and 79%, respectively, in the evaluable population. The odds ratio Spfx/ROXI for success was 4.5 (95% confidence interval, 1.9, 10.8) for the evaluable population. Both drugs were, overall, equally safe. GI symptoms were the most common adverse experiences in both groups. Prolongation of QTc, without clinical symptoms, was seen in 3% of Spfx patients and in 1% of ROXI patients, and photosensitivity, mostly mild to moderate, was seen in 5% of the Spfx group.

    CONCLUSIONS:

    Oral treatment with Spfx was superior to ROXI for the treatment of moderately severe CAP. Spfx was effective for all isolated pathogens, including S pneumoniae, and may be an alternative for empiric treatment of CAP, especially in areas with a high incidence of beta-lactam-resistant pneumococci.

  • 101033.
    Örulv, Linda
    Linköping University, Faculty of Arts and Sciences. Linköping University, Department of Medical and Health Sciences, Health and Society.
    Demens: diagnosen som utmanar våra rädslor och fördomar2011In: Diagnos & identitet / [ed] Georg Drakos, Lars-Christer Hydén, Stockholm: Gothia Förlag AB, 2011, p. 100-129Chapter in book (Other academic)
  • 101034.
    Örulv, Linda
    Linköping University, Department of Medical and Health Sciences, Health and Society. Linköping University, Faculty of Arts and Sciences.
    Fragile identities, patched-up worlds: Dementia and meaning-making in social interaction2008Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis focuses on the identity work and the meaning- or sense-making that continue in the face of evolving dementia diseases, in social interaction, and the challenges for care this involves. The study adopts an actor-oriented approach and addresses the question of how persons with age-related progressive dementia diseases in everyday communication make sense of their situations, their surroundings, and their lives – all within the context of daily life in residential care. Of particular interest is how these persons handle issues of joint action in a shared world and how they establish and maintain an identity in the inte-raction. This is in spite of severe memory problems, disorientation in time and space, dif-fering understandings of the current situation, and difficulties in telling “accurate” and temporally ordered stories about their lives. The thesis also addresses the question of how caregivers may handle the complex interplay between residents in daily care, in maintain-ing and respecting these persons’ dignity.

    The study follows a growing tradition of studying interaction in dementia as mean-ing-based and situated in a context rather than merely as behavior caused by cognitive impairment. Methodologically, this is an ethnographic study based on observations made within a period of six months. The data consist of around 150 hours of video recordings and complementary field notes. This extensive material has made it possible to study the social interaction both in detail and situated in a larger context.

    The findings point to remaining competences and strategies that persons with demen-tia use actively and creatively in the ongoing interaction – and, given the premises, often in a rational way. This is discussed in terms of resources for dementia care, in relation to the great challenge of patching up and putting together a comprehensive socially shared world as well as maintaining continuity with the persons’ previous life histories in a way that preserves a positive self-identity.

    List of papers
    1. Confabulation: sense-making, self-making and world-making in dementia
    Open this publication in new window or tab >>Confabulation: sense-making, self-making and world-making in dementia
    2006 (English)In: Discourse Studies, ISSN 1461-4456, Vol. 8, no 5, p. 647-673Article in journal (Refereed) Published
    Abstract [en]

    This study is concerned with the productive aspects of confabulation as it occurs spontaneously in dementia care, in its context, and in interaction with other care recipients. Confabulation is approached as a social and discursive event with distinct narrative features; plots and formerly established genres of plots, storylines, are used by confabulators in order to understand, manage and interact socially in the present situation. Three main functions of confabulation are discerned: 1) making sense of the current situation (sense-making); 2) maintaining a personal identity in interaction with others (self-making); and 3) organizing and legitimizing joint action in the world (world-making). The resources used by confabulating subjects are sparse and not well adjusted to changing conditions, as the number of accessible storylines is limited. This makes it difficult to apply storylines that explain the current situation satisfactorily, provide useful guidelines for how to act, as well as preserve a positive self-identity. Helping with this constitutes a major challenge in dementia care.

    Keywords
    Alzheimer’s disease, communication, confabulation, context, dementiam, ethnography
    National Category
    Communication Studies
    Identifiers
    urn:nbn:se:liu:diva-13251 (URN)10.1177/1461445606067333 (DOI)
    Available from: 2008-05-06 Created: 2008-05-06 Last updated: 2013-09-04
    2. Placing the place, and placing oneself within it: (dis)orientation and (dis)continuity in dementia
    Open this publication in new window or tab >>Placing the place, and placing oneself within it: (dis)orientation and (dis)continuity in dementia
    2010 (English)In: Dementia, ISSN 1471-3012, E-ISSN 1741-2684, Vol. 9, p. 21-44Article in journal (Refereed) Published
    Abstract [en]

    Disorientation as experienced by persons with progressive dementia diseases involves both existential and social dimensions. Based on video observations from a small residential care unit and exploring social interaction on a micro-level, this case study focuses on how a woman with vascular dementia actively tries to make sense of an everyday lunch situation. The analysis addresses strategies used by her to contextualize where she has ended up, and also how the meaning of the place is altered in communication. Findings point to social interaction between residents as an important resource to help maintain continuity with previous social life. However, there also seems to be an impending need for caregivers to help residents patch up their broken life-stories to render everyday situations comprehensible and the setting socially meaningful. Helping them find a way of placing themselves within it — also affording a positive self-identity and continuity with previous life history — is a major challenge in daily care.

    Place, publisher, year, edition, pages
    Sage Publications, 2010
    National Category
    Social Sciences
    Identifiers
    urn:nbn:se:liu:diva-13252 (URN)10.1177/1471301210364449 (DOI)
    Available from: 2008-05-06 Created: 2008-05-06 Last updated: 2017-12-13Bibliographically approved
    3. Narrative and identity in Alzheimer’s disease: a case study
    Open this publication in new window or tab >>Narrative and identity in Alzheimer’s disease: a case study
    2009 (English)In: Journal of Aging Studies, ISSN 0890-4065, E-ISSN 1879-193X, Vol. 23, no 4, p. 205-214Article in journal (Refereed) Published
    Abstract [en]

    In this case study, focus is on how persons with AD use their remaining linguistic and cognitive resources, together with non-verbal aspects of the storytelling event, as resources in communicating and negotiating their identities in everyday encounters. The results of the analysis, focusing on the telling of the stories, indicate that other aspects than the temporal and referential organization of the narratives has become important resources for the teller in establishing and negotiating identity. The telling of temporally discontinuous narratives does not appear to affect or disrupt the teller's experience of some sort of a continuous sense of self and identity but are probably more a problem to persons without this kind of diagnosis. Being afflicted by AD most likely leads persons to try to invent and use alternative communicative recourses in order to sustain factors like their senses of self and identities. For researchers this makes it important to try to base their analysis on the actual organization of the talk and to focus on the functions of various responses and utterances in the interaction.

    Keywords
    identity, narrative, Alzheimer’s disease, performance, story-telling
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-13253 (URN)10.1016/j.jaging.2008.01.001 (DOI)
    Available from: 2008-05-06 Created: 2008-05-06 Last updated: 2017-12-13
    4. Dignity work in dementia care: Sketching a microethical analysis
    Open this publication in new window or tab >>Dignity work in dementia care: Sketching a microethical analysis
    2007 (English)In: Dementia: the International Journal of Social Research and Practice, ISSN 1471-3012, Vol. 6, no 4, p. 507-525Article in journal (Refereed) Published
    Abstract [en]

    This study is concerned with issues of dignity in dementia care, in situations where staff members handle potential or actual conflicts and interaction problems between residents. Based on empirical data consisting of observations and video recordings, various coping strategies are identified in regard to whether or not, as well as when and how to interfere. Microethical analysis is used in order to discuss these coping strategies in relation to contextual conditions and ways of understanding, and values or aspects of dignity are highlighted. In dialogue with empirical data, nuances of ethical considerations are approached that are otherwise difficult to access analytically — thereby opening the door to a more reflective way of dealing with problematic situations in dementia care.

    Keywords
    coping strategies • conflict solving • ethics • ethnography • microethics
    National Category
    Social Sciences
    Identifiers
    urn:nbn:se:liu:diva-13254 (URN)10.1177/1471301207084368 (DOI)
    Available from: 2008-05-06 Created: 2008-05-06 Last updated: 2009-03-09Bibliographically approved
  • 101035.
    Örulv, Linda
    Linköping University, Department of Medical and Health Sciences, Health and Society. Linköping University, Faculty of Health Sciences.
    Placing the place, and placing oneself within it: (dis)orientation and (dis)continuity in dementia2010In: Dementia, ISSN 1471-3012, E-ISSN 1741-2684, Vol. 9, p. 21-44Article in journal (Refereed)
    Abstract [en]

    Disorientation as experienced by persons with progressive dementia diseases involves both existential and social dimensions. Based on video observations from a small residential care unit and exploring social interaction on a micro-level, this case study focuses on how a woman with vascular dementia actively tries to make sense of an everyday lunch situation. The analysis addresses strategies used by her to contextualize where she has ended up, and also how the meaning of the place is altered in communication. Findings point to social interaction between residents as an important resource to help maintain continuity with previous social life. However, there also seems to be an impending need for caregivers to help residents patch up their broken life-stories to render everyday situations comprehensible and the setting socially meaningful. Helping them find a way of placing themselves within it — also affording a positive self-identity and continuity with previous life history — is a major challenge in daily care.

  • 101036.
    Örulv, Linda
    Linköping University, Department of Medical and Health Sciences, Health and Society. Linköping University, Faculty of Arts and Sciences.
    Reframing dementia in Swedish self-help group conversations: Constructing citizenship2012In: International journal of self help & self care, ISSN 1091-2851, E-ISSN 1541-4450, Vol. 6, no 1, p. 9-41Article in journal (Refereed)
    Abstract [en]

    This study explores on a micro-level the activity of a self-help group for persons with dementia in Swedish municipal care, based on audio-recordings from 18 months' ethnographic fieldwork. The study focuses on the discursive construction of a shared meaning perspective and its inherent possibilities for liberation. Applying a citizenship perspective, the study approaches people with dementia as vulnerable to marginalization while at the same time capable of agency within the boundaries of their condition. The findings paint a complex picture involving opportunities and limitations of experiential knowledge, issues of double stigmatization, and constructs of being interrelated with other people and with the surrounding society. In the center is the overarching struggle of retaining citizenship in the face of the evolving disease.

  • 101037.
    Örulv, Linda
    Linköping University, Department of Social and Welfare Studies, NISAL - National Institute for the Study of Ageing and Later Life. Linköping University, Faculty of Arts and Sciences.
    Självhjälpsgrupper, nätverk och aktivism2016In: Att leva med demens / [ed] Ingrid Hellström, Lars-Christer Hydén, Malmö: Gleerups Utbildning AB, 2016, 1, p. 203-211Chapter in book (Other academic)
  • 101038.
    Örulv, Linda
    Linköping University, Department of Medical and Health Sciences, Health and Society. Linköping University, Faculty of Arts and Sciences.
    The subjectivity of disorientation: moral stakes and concerns2014In: Beyond Loss: dementia, identity, personhood / [ed] Lars-Christer Hydén, Hilde Lindemann, and Jens Brockmeier, Oxford: Oxford University Press, 2014, p. 191-207Chapter in book (Refereed)
    Abstract [en]

    This collection of interdisciplinary essays by international researchers tries to see beyond the loss in dementia, exploring it as transformation and change of personhood and identity that typically is embedded in social life. The chapters identify three important themes: persons and personhood, identity and agency, and the social and the communal.

  • 101039.
    Örulv, Linda
    Linköping University, Faculty of Arts and Sciences. Linköping University, The Tema Institute, Department of Communications Studies.
    Where are we? What's going to happen? Spontaneous narrating and dementia (presentation baserad på artikelarbete tillsammans med Lars-Christer Hydén)2003In: First Interdisciplinary Conference on Communication, Medicine Ethics COMET, 26-28 June 2003,2003, 2003Conference paper (Other academic)
    Abstract [en]

      

  • 101040.
    Örulv, Linda
    et al.
    Linköping University, Department of Medicine and Health Sciences, Health and Society. Linköping University, Faculty of Arts and Sciences.
    Hydén, Lars-Christer
    Linköping University, Department of Medicine and Health Sciences, Health and Society. Linköping University, Faculty of Arts and Sciences.
    Confabulation: sense-making, self-making and world-making in dementia2006In: Discourse Studies, ISSN 1461-4456, Vol. 8, no 5, p. 647-673Article in journal (Refereed)
    Abstract [en]

    This study is concerned with the productive aspects of confabulation as it occurs spontaneously in dementia care, in its context, and in interaction with other care recipients. Confabulation is approached as a social and discursive event with distinct narrative features; plots and formerly established genres of plots, storylines, are used by confabulators in order to understand, manage and interact socially in the present situation. Three main functions of confabulation are discerned: 1) making sense of the current situation (sense-making); 2) maintaining a personal identity in interaction with others (self-making); and 3) organizing and legitimizing joint action in the world (world-making). The resources used by confabulating subjects are sparse and not well adjusted to changing conditions, as the number of accessible storylines is limited. This makes it difficult to apply storylines that explain the current situation satisfactorily, provide useful guidelines for how to act, as well as preserve a positive self-identity. Helping with this constitutes a major challenge in dementia care.

  • 101041.
    Örulv, Linda
    et al.
    Linköping University, Department of Medicine and Health Sciences, Health and Society. Linköping University, Faculty of Arts and Sciences.
    Nikku, Nina
    Linköping University, Department of Behavioural Sciences and Learning, Sociology . Linköping University, Faculty of Arts and Sciences.
    Dignity work in dementia care: Sketching a microethical analysis2007In: Dementia: the International Journal of Social Research and Practice, ISSN 1471-3012, Vol. 6, no 4, p. 507-525Article in journal (Refereed)
    Abstract [en]

    This study is concerned with issues of dignity in dementia care, in situations where staff members handle potential or actual conflicts and interaction problems between residents. Based on empirical data consisting of observations and video recordings, various coping strategies are identified in regard to whether or not, as well as when and how to interfere. Microethical analysis is used in order to discuss these coping strategies in relation to contextual conditions and ways of understanding, and values or aspects of dignity are highlighted. In dialogue with empirical data, nuances of ethical considerations are approached that are otherwise difficult to access analytically — thereby opening the door to a more reflective way of dealing with problematic situations in dementia care.

  • 101042.
    Örulv, Linda
    et al.
    Linköping University, Department of Social and Welfare Studies, NISAL - National Institute for the Study of Ageing and Later Life. Linköping University, Faculty of Arts and Sciences.
    Strandroos, Lisa
    Linköping University, Department of Social and Welfare Studies, NISAL - National Institute for the Study of Ageing and Later Life. Linköping University, Faculty of Arts and Sciences.
    Vardagsdraman på det särskilda boendet2016In: Att leva med demens / [ed] Ingrid Hellström, Lars-Christer Hydén, Malmö: Gleerups Utbildning AB, 2016, 1, p. 79-86Chapter in book (Other academic)
  • 101043.
    Öst, Anita
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Lipid Metabolism andInsulin Signalling in Adipocytes: enhanced autophagy in type 2 diabetes2009Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Energy storage in the adipose tissue, to an extent leading to obesity, is associated with local as well assystemic insulin resistance. When insulin-producing beta-cells in the pancreas gradually fail tocompensate, plasma levels of glucose rise and overt type 2 diabetes is diagnosed. Adipocytes are largecells, mostly consisting of one big central lipid droplet, with the surrounding plasma membrane full ofsmall invaginations called caveolae. As caveolae contain the insulin receptor and several other insulinsignallingproteins, we have investigated several aspects of caveolae. We have also mapped mechanismsand defects in the insulin-signalling network in adipocytes from type 2 diabetic patients.

    In paper I, we show that a subtype of caveolae has the capability to synthesize triglycerides from fattyacids and glycerol-3-phosphate. The triglyceride-synthesizing caveolae subtype also contains perilipin,suggesting the existence of a mechanism to protect newly made triglycerides from hydrolysis.

    In paper II, we demonstrate that adipocytes from patients with type 2 diabetes have an attenuated insulinstimulatedphosphorylation of IRS-1 at Ser-307 (human sequence), which correlates with reduced insulinstimulatedphosphorylation of IRS-1 at tyrosine residues. Insulin-stimulated phosphorylation of IRS-1 atSer-307 is dependent on the nutrient sensor TORC1. This finding indicates that adipocytes from type 2diabetic patients have reduced TORC1 activity.

    In paper III, we focus on the mechanisms for RBP4-induced insulin resistance. We also continue ourmapping of insulin-resistance in adipocytes from type 2 diabetes. These cells exhibit, in addition toimpaired insulin-stimulated glucose uptake and the defects presented in paper I, impaired insulinstimulatedphosphorylation of ERK. We do, however, not see any defects in PKB signalling. Neither dowe se any enhanced insulin-stimulated phosphorylation of IRS-1 at Ser-312 (human sequence), a site thatin mice is hyper-stimulated in response to high-fat feeding. Incubation with RBP4 recapitulates all defectswe so far have seen in type 2 diabetes except reduced insulin-stimulated glucose uptake. These results aremirrored by blockade of endogenously produced RBP4 in the incubations with adipocytes from type 2diabetic patients. In other words, RBP4-blocking antibodies restore all insulin-signalling defects we havefound in adipocytes from type 2 diabetic patients, except insulin-stimulated glucose uptake.

    In paper IV we show by several approaches that TORC1 activation is down-regulated in adipocytes fromtype 2 diabetic patients. The main finding is that there is enhanced autophagy in those adipocytes.Interestingly, autophagy may be a mechanism to enhance the breakdown of stored triglycerides in theadipocyte.

    In conclusion, our data suggest that caveolae, in addition to being micro-domains for insulin-signallingare metabolic platforms. We describe defects in insulin-signalling in adipocytes from type 2 diabeticpatients where the main finding is enhanced autophagy in these obese patients. The perceived starvationin adipose tissue might via secretion of adipokines, such as RBP4, have implications for local as well assystemic insulin-resistance.

    List of papers
    1. Triacylglycerol is synthesized in a specific subclass of caveolae in primary adipocytes
    Open this publication in new window or tab >>Triacylglycerol is synthesized in a specific subclass of caveolae in primary adipocytes
    Show others...
    2005 (English)In: Journal of Biological Chemistry, ISSN 0021-9258, E-ISSN 1083-351X, Vol. 280, no 1, p. 5-8Article in journal (Refereed) Published
    Abstract [en]

    A principal metabolic function of adipocytes is to synthesize triacylglycerol (TG) from exogenous fatty acids. The level of fatty acids has to be tightly controlled in the adipocyte, as they can act as detergents that rapidly dissolve the plasma membrane, causing cell lysis if allowed to accumulate. Fatty acids therefore have to be efficiently converted to TG and stored in the central lipid droplet. We report that in intact primary adipocytes exogenous oleic acid was taken up and directly converted to TG in the plasma membrane, in a novel subclass of caveolae that specifically contains the protein perilipin. Isolated caveolae catalyzed de novo TG synthesis from oleic acid and glycerol 3-phosphate. Electron microscopy revealed the presence of caveolin and perilipin in caveolae and in lipid-laden bulbs in the plasma membrane, and fluorescence microscopy demonstrated colocalization of fatty acids/TG with caveolin and perilipin at the plasma membrane. A second caveolae fraction was isolated, which lacked perilipin and the triacylglycerol synthesizing enzymes. Both caveolae fractions contained caveolin-1 and the insulin receptor. The findings demonstrate that specific subclasses of caveolae carry out specific functions in cell metabolism. In particular, triacylglycerol is synthesized at the site of fatty acid entry in one of these caveolae classes.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-20650 (URN)10.1074/jbc.C400429200 (DOI)15537657 (PubMedID)
    Available from: 2009-09-16 Created: 2009-09-16 Last updated: 2017-12-13Bibliographically approved
    2. Attenuation of insulin-stimulated insulin receptor substrate-1 serine 307 phosphorylation in insulin resistance of type 2 diabetes
    Open this publication in new window or tab >>Attenuation of insulin-stimulated insulin receptor substrate-1 serine 307 phosphorylation in insulin resistance of type 2 diabetes
    2005 (English)In: Journal of biological chemistry, ISSN 0021-9258, Vol. 280, no 41, p. 34389-3492Article in journal (Refereed) Published
    Abstract [en]

    Insulin resistance is a primary characteristic of type 2 diabetes and likely causally related to the pathogenesis of the disease. It is a result of defects in signal transduction from the cell surface receptor of insulin to target effects. We found that insulin-stimulated phosphorylation of serine 307 (corresponding to serine 302 in the murine sequence) in the immediate downstream mediator protein of the insulin receptor, insulin receptor substrate-1 (IRS1), is required for efficient insulin signaling and that this phosphorylation is attenuated in adipocytes from patients with type 2 diabetes. Inhibition of serine 307 phosphorylation by rapamycin mimicked type 2 diabetes and reduced the sensitivity of IRS1 tyrosine phosphorylation in response to insulin, while stimulation of the phosphorylation by okadaic acid, in cells from patients with type 2 diabetes, rescued cells from insulin resistance. EC50 for insulin-stimulated phosphorylation of serine 307 was about 0.2 nM with a t1/2 of about 2 min. The amount of IRS1 was similar in cells from non-diabetic and diabetic subjects. These findings identify a molecular mechanism for insulin resistance in non-selected patients with type 2 diabetes.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-12791 (URN)10.1074/jbc.C500230200 (DOI)
    Available from: 2007-11-23 Created: 2007-11-23 Last updated: 2013-09-10Bibliographically approved
    3. Retinol-binding protein-4 attenuates insulin-induced phosphorylation of IRS1 and ERK1/2 in primary human adipocytes
    Open this publication in new window or tab >>Retinol-binding protein-4 attenuates insulin-induced phosphorylation of IRS1 and ERK1/2 in primary human adipocytes
    Show others...
    2007 (English)In: The FASEB journal : official publication of the Federation of American Societies for Experimental Biology, ISSN 1530-6860, Vol. 21, no 13, p. 3696-3704Article in journal (Refereed) Published
    Abstract [en]

    Reduced sensitivity to insulin in adipose, muscle, and liver tissues is a hallmark of type 2 diabetes. Animal models and patients with type 2 diabetes exhibit elevated levels of circulating retinol-binding protein (RBP4), and RBP4 can induce insulin resistance in mice. However, little is known about how RBP4 affects insulin signaling. We examined the mechanisms of action of RBP4 in primary human adipocytes. RBP4-treated adipocytes exhibited the same molecular defects in insulin signaling, via IRS1 to MAP kinase, as in adipocytes from patients with type 2 diabetes. Without affecting autophosphorylation of the insulin receptor, RBP4 blocked the insulin-stimulated phosphorylation of IRS1 at serine (307) [corresponding to serine (302) in the murine sequence] and concomitantly increased the EC50 (from 0.5 to 2 nM) for insulin stimulation of IRS1 phosphorylation at tyrosine. The phosphorylation of IRS1 at serine (312) [corresponding to serine (307) in the murine sequence] was not affected in cells from diabetic patients and was also not affected by RBP4. The EC50 for insulin stimulation of downstream phosphorylation of MAP kinase ERK1/2 was increased (from 0.2 to 0.8 nM) by RBP4. We show that ERK1/2 phosphorylation is similarly impaired in adipocytes from patients with type 2 diabetes. However, the sensitivity to insulin for downstream signaling to control of protein kinase B and glucose uptake was not affected by RBP4. When insulin-resistant adipocytes from patients with type 2 diabetes were incubated with antibodies against RBP4, insulin-induced phosphorylation of IRS1 at serine (307) was normalized and the EC50 for insulin stimulation of ERK1/2 phosphorylation was reduced. Endogenous levels of RBP4 were markedly reduced in adipocytes from obese or type 2 diabetic subjects, whereas expression levels of RBP4 mRNA were unaffected. These findings indicate that RBP4 may be released from diabetic adipocytes and act locally to inhibit phosphorylation of IRS1 at serine (307), a phosphorylation site that may integrate nutrient sensing with insulin signaling.

    Keywords
    Insulin resistance, type 2 diabetes, adipokine, protein phosphorylation, MAP kinase
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-20654 (URN)10.1096/fj.07-8173com (DOI)17575262 (PubMedID)
    Available from: 2009-09-16 Created: 2009-09-16 Last updated: 2013-09-10Bibliographically approved
    4. Attenuated mTOR signaling and enhanced autophagy in adipocytes from obese patients with type 2 diabetes
    Open this publication in new window or tab >>Attenuated mTOR signaling and enhanced autophagy in adipocytes from obese patients with type 2 diabetes
    Show others...
    2010 (English)In: Molecular medicine (Cambridge, Mass. Print), ISSN 1076-1551, E-ISSN 1528-3658, Vol. 16, no 07-Aug, p. 235-246Article in journal (Refereed) Published
    Abstract [en]

    The protein kinase mammalian target of rapamycin (mTOR) mediates insulin control ofprotein synthesis, autophagy, mitochondrial function, and, through feedback signaling tophosphorylation of IRS1 at serine residues, mTOR directly controls insulin signaling. Weshow that in adipocytes from patients with type 2 diabetes (T2D) insulin activation of mTORis attenuated and that the resultant phenotype is compatible with, and can be mimicked by,loss of mTOR activation. In T2D adipocytes mitochondrial function is impaired andautophagy strongly upregulated, with concomitant increased autophagic destruction ofmitochondria and lipofuscin particles, and a dependence on autophagy for ATP production.Conversely, mitochondrial dysfunction attenuates insulin activation of mTOR, enhancesautophagy and attenuates feedback to IRS1. Our findings put mTOR in the driver´s seat of aninsulin resistance that in adipocytes can be fuelled by mitochondrial dysfunction,inflammation, ER-stress, or hypoxia.

    Place, publisher, year, edition, pages
    Feinstein Institute for Medical Research, 2010
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-20655 (URN)10.2119/molmed.2010.00023 (DOI)000280048100001 ()20386866 (PubMedID)
    Available from: 2009-09-16 Created: 2009-09-16 Last updated: 2019-06-28Bibliographically approved
  • 101044.
    Öst, Anita
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Danielsson, Anna
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Lidén, Martin
    Ludwig Institute for Cancer Research, Stockholm, Sweden.
    Eriksson, Ulf
    Ludwig Institute for Cancer Research, Stockholm, Sweden.
    Nyström, Fredrik H
    Linköping University, Department of Medicine and Health Sciences, Internal Medicine . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Local Health Care Services in Central Östergötland, Department of Endocrinology and Gastroenterology.
    Strålfors, Peter
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Retinol-binding protein-4 attenuates insulin-induced phosphorylation of IRS1 and ERK1/2 in primary human adipocytes2007In: The FASEB journal : official publication of the Federation of American Societies for Experimental Biology, ISSN 1530-6860, Vol. 21, no 13, p. 3696-3704Article in journal (Refereed)
    Abstract [en]

    Reduced sensitivity to insulin in adipose, muscle, and liver tissues is a hallmark of type 2 diabetes. Animal models and patients with type 2 diabetes exhibit elevated levels of circulating retinol-binding protein (RBP4), and RBP4 can induce insulin resistance in mice. However, little is known about how RBP4 affects insulin signaling. We examined the mechanisms of action of RBP4 in primary human adipocytes. RBP4-treated adipocytes exhibited the same molecular defects in insulin signaling, via IRS1 to MAP kinase, as in adipocytes from patients with type 2 diabetes. Without affecting autophosphorylation of the insulin receptor, RBP4 blocked the insulin-stimulated phosphorylation of IRS1 at serine (307) [corresponding to serine (302) in the murine sequence] and concomitantly increased the EC50 (from 0.5 to 2 nM) for insulin stimulation of IRS1 phosphorylation at tyrosine. The phosphorylation of IRS1 at serine (312) [corresponding to serine (307) in the murine sequence] was not affected in cells from diabetic patients and was also not affected by RBP4. The EC50 for insulin stimulation of downstream phosphorylation of MAP kinase ERK1/2 was increased (from 0.2 to 0.8 nM) by RBP4. We show that ERK1/2 phosphorylation is similarly impaired in adipocytes from patients with type 2 diabetes. However, the sensitivity to insulin for downstream signaling to control of protein kinase B and glucose uptake was not affected by RBP4. When insulin-resistant adipocytes from patients with type 2 diabetes were incubated with antibodies against RBP4, insulin-induced phosphorylation of IRS1 at serine (307) was normalized and the EC50 for insulin stimulation of ERK1/2 phosphorylation was reduced. Endogenous levels of RBP4 were markedly reduced in adipocytes from obese or type 2 diabetic subjects, whereas expression levels of RBP4 mRNA were unaffected. These findings indicate that RBP4 may be released from diabetic adipocytes and act locally to inhibit phosphorylation of IRS1 at serine (307), a phosphorylation site that may integrate nutrient sensing with insulin signaling.

  • 101045.
    Öst, Anita
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Cell Biology. Linköping University, Faculty of Health Sciences. Max Planck Institute Immunobiol and Epigenet, Germany.
    Lempradl, Adelheid
    Max Planck Institute Immunobiol and Epigenet, Germany.
    Casas, Eduard
    Institute Medical Predict and Personalitzada Canc, Spain; ICO Hospital GermansTrias and Pujol, Spain.
    Weigert, Melanie
    Max Planck Institute Immunobiol and Epigenet, Germany.
    Tiko, Theodor
    Max Planck Institute Immunobiol and Epigenet, Germany.
    Deniz, Merdin
    Max Planck Institute Immunobiol and Epigenet, Germany.
    Pantano, Lorena
    Institute Medical Predict and Personalitzada Canc, Spain.
    Boenisch, Ulrike
    Max Planck Institute Immunobiol and Epigenet, Germany.
    Itskov, Pavel M.
    Champalimaud Centre Unknown, Portugal.
    Stoeckius, Marlon
    Max Delbruck Centre Molecular Med, Germany.
    Ruf, Marius
    Max Planck Institute Immunobiol and Epigenet, Germany.
    Rajewsky, Nikolaus
    Max Delbruck Centre Molecular Med, Germany.
    Reuter, Gunter
    University of Halle Wittenberg, Germany.
    Iovino, Nicola
    Max Planck Institute Immunobiol and Epigenet, Germany.
    Ribeiro, Carlos
    Champalimaud Centre Unknown, Portugal.
    Alenius, Mattias
    Linköping University, Department of Clinical and Experimental Medicine, Division of Cell Biology. Linköping University, Faculty of Health Sciences.
    Heyne, Steffen
    Max Planck Institute Immunobiol and Epigenet, Germany.
    Vavouri, Tanya
    Institute Medical Predict and Personalitzada Canc, Spain; ICO Hospital GermansTrias and Pujol, Spain.
    Pospisilik, J. Andrew
    Max Planck Institute Immunobiol and Epigenet, Germany.
    Paternal Diet Defines Offspring Chromatin State and Intergenerational Obesity2014In: Cell, ISSN 0092-8674, E-ISSN 1097-4172, Vol. 159, no 6, p. 1352-1364Article in journal (Refereed)
    Abstract [en]

    The global rise in obesity has revitalized a search for genetic and epigenetic factors underlying the disease. We present a Drosophila model of paternal-diet-induced intergenerational metabolic reprogramming (IGMR) and identify genes required for its encoding in offspring. Intriguingly, we find that as little as 2 days of dietary intervention in fathers elicits obesity in offspring. Paternal sugar acts as a physiological suppressor of variegation, desilencing chromatin-state-defined domains in both mature sperm and in offspring embryos. We identify requirements for H3K9/K27me3-dependent reprogramming of metabolic genes in two distinct germline and zygotic windows. Critically, we find evidence that a similar system may regulate obesity susceptibility and phenotype variation in mice and humans. The findings provide insight into the mechanisms underlying intergenerational metabolic reprogramming and carry profound implications for our understanding of phenotypic variation and evolution.

  • 101046.
    Öst, Anita
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Cell Biology. Linköping University, Faculty of Health Sciences.
    Pospisilik, John Andrew
    Max Planck Institute of Immunobiology and Epigenetics, Freiburg, Germany.
    Epigenetic modulation of metabolic decisions.2015In: Current Opinion in Cell Biology, ISSN 0955-0674, E-ISSN 1879-0410, Vol. 33, p. 88-94Article, review/survey (Refereed)
    Abstract [en]

    In the recent years there has been a tremendous increase in our understanding of chromatin, transcription and the importance of metabolites in their regulation. This review highlights what is currently sparse information that suggest existence of a refined system integrating metabolic and chromatin control. We indicate possible regulatory modes, such as feed forward amplification, that may help effect and stabilize long-lasting phenotypic decisions within and even across generations using adipogenesis as the primary context.

  • 101047.
    Öst, Anita
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Svensson, Kristoffer
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Ruishalme, Iida
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Brännmark, Cecilia
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Franck, Niclas
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Krook, Hans
    Linköping University, Department of Clinical and Experimental Medicine, Surgery . Linköping University, Faculty of Health Sciences.
    Sandström, Per
    Linköping University, Department of Clinical and Experimental Medicine, Surgery . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Surgery in Östergötland.
    Kjølhede, Preben
    Linköping University, Department of Clinical and Experimental Medicine, Obstetrics and gynecology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre of Paediatrics and Gynecology and Obstetrics, Department of Gynecology and Obstetrics UHL.
    Strålfors, Peter
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Attenuated mTOR signaling and enhanced autophagy in adipocytes from obese patients with type 2 diabetes2010In: Molecular medicine (Cambridge, Mass. Print), ISSN 1076-1551, E-ISSN 1528-3658, Vol. 16, no 07-Aug, p. 235-246Article in journal (Refereed)
    Abstract [en]

    The protein kinase mammalian target of rapamycin (mTOR) mediates insulin control ofprotein synthesis, autophagy, mitochondrial function, and, through feedback signaling tophosphorylation of IRS1 at serine residues, mTOR directly controls insulin signaling. Weshow that in adipocytes from patients with type 2 diabetes (T2D) insulin activation of mTORis attenuated and that the resultant phenotype is compatible with, and can be mimicked by,loss of mTOR activation. In T2D adipocytes mitochondrial function is impaired andautophagy strongly upregulated, with concomitant increased autophagic destruction ofmitochondria and lipofuscin particles, and a dependence on autophagy for ATP production.Conversely, mitochondrial dysfunction attenuates insulin activation of mTOR, enhancesautophagy and attenuates feedback to IRS1. Our findings put mTOR in the driver´s seat of aninsulin resistance that in adipocytes can be fuelled by mitochondrial dysfunction,inflammation, ER-stress, or hypoxia.

  • 101048.
    Öst, Anita
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Örtegren, Unn
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Gustavsson, Johanna
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Nyström, Fredrik H
    Linköping University, Department of Medical and Health Sciences, Internal Medicine. Linköping University, Faculty of Health Sciences.
    Strålfors, Peter
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Triacylglycerol is synthesized in a specific subclass of caveolae in primary adipocytes2005In: Journal of Biological Chemistry, ISSN 0021-9258, E-ISSN 1083-351X, Vol. 280, no 1, p. 5-8Article in journal (Refereed)
    Abstract [en]

    A principal metabolic function of adipocytes is to synthesize triacylglycerol (TG) from exogenous fatty acids. The level of fatty acids has to be tightly controlled in the adipocyte, as they can act as detergents that rapidly dissolve the plasma membrane, causing cell lysis if allowed to accumulate. Fatty acids therefore have to be efficiently converted to TG and stored in the central lipid droplet. We report that in intact primary adipocytes exogenous oleic acid was taken up and directly converted to TG in the plasma membrane, in a novel subclass of caveolae that specifically contains the protein perilipin. Isolated caveolae catalyzed de novo TG synthesis from oleic acid and glycerol 3-phosphate. Electron microscopy revealed the presence of caveolin and perilipin in caveolae and in lipid-laden bulbs in the plasma membrane, and fluorescence microscopy demonstrated colocalization of fatty acids/TG with caveolin and perilipin at the plasma membrane. A second caveolae fraction was isolated, which lacked perilipin and the triacylglycerol synthesizing enzymes. Both caveolae fractions contained caveolin-1 and the insulin receptor. The findings demonstrate that specific subclasses of caveolae carry out specific functions in cell metabolism. In particular, triacylglycerol is synthesized at the site of fatty acid entry in one of these caveolae classes.

  • 101049.
    Öst, Gustav
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    Search path generation with UAV applications using approximate convex decomposition2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This work focuses on the problem that pertains to area searching with UAVs. Specifically developing algorithms that generate flight paths that are short with- out sacrificing flyability. For instance, very sharp turns will compromise flyability since fixed wing aircraft cannot make very sharp turns. This thesis provides an analysis of different types of search methods, area decompositions, and combi- nations thereof. The search methods used are side to side searching and spiral searching. In side to side searching the aircraft goes back and forth only making 90-degree turns. Spiral search searches the shape in a spiral pattern starting on the outer perimeter working its way in. The idea being that it should generate flight paths that are easy to fly since all turns should be with a large turn radii. Area decomposition is done to divide complex shapes into smaller more manage- able shapes. The report concludes that with the implemented methods the side to side scanning method without area decomposition yields good and above all very reliable results. The reliability stems from the fact that all turns are 90 degrees and that algorithm never get stuck or makes bad mistakes. Only having 90 degree turns results in only four different types of turns. This allows the airplanes behav- ior along the route to be predictable after flying the first four turns. Although this assumes that the strength of the wind is a greater influence than the turbulences effect on the aircraft’s flight characteristics. This is a very valuable feature for an operator in charge of a flight. The other tested methods and area decompositions often yield a shorter flight path, however, despite extensive adjustments to the algorithms they never came to handle all cases in a satisfactory manner. These methods may also generate any kind of turn at any time, including turns of nearly 180 degrees. These turns can lead to an airplane missing the intended flight path and thus missing to scan the intended area properly. Area decomposition proves to be really effective only when the area has many protrusions that stick out in different directions, think of a starfish shape. In these cases the side to side algo- rithm generate a path that has long legs over parts that are not in the search area. When the area is decomposed the algorithm starts with, for example, one arm of the starfish at a time and then search the rest of the arms and body in turn. 

  • 101050.
    Östberg, AL
    et al.
    Public Dental Services and Skaraborg Institute, Skövde.
    Halling, Arne
    Östergötlands Läns Landsting, Public Dental Service.
    Lindblad, U
    Public Dental Services and Skaraborg Institute, Skövde.
    A gender perspective of self-perceived oral health in adolescents: associations with attitudes and behaviours2001In: Community Dental Health, ISSN 0265-539X, Vol. 18, no 2, p. 110-116Article in journal (Refereed)
    Abstract [en]

    Objective To investigate the associations between dental attitudes and behaviours, and self-perceived oral health from a gender perspective in an adolescent population. Design A census survey. Self-reported questionnaires were answered anonymously in a standardised manner in classrooms. Attitudes studied included the importance of sound teeth and feelings towards visits to the dentist. Behaviours were represented by floss usage and sweets consumption. Setting All senior and upper secondary level schools in Skaraborg County, Sweden. Subjects 17,280 students, aged 13-18 years, Outcome measures Self-perceived oral health. represented by a single-item rating: satisfaction with the appearance of the teeth: self-assessed gum bleeding and a perceived oral health (POH) index. Results Recognising sound teeth as important was a predominating attitude among the respondents (boys 94%, girls 97%) and was significantly associated with a good perceived oral health overall. Individuals who experienced visits to dentist as unpleasant (boys 36%, girls 43%) were less likely to perceive good oral health as single-item rated (OR for boys 0.55[0.49, 0.63], girls 0.40[0.34, 0.47]). Regular use of floss had a small protective effect on bleeding gums. Daily sweets consumption showed a significant and inverse association with self-perceived oral health as single-item rated (OR for boys 0.53[0.44, 0.66], girls 0.49[0.40, 0.60]). Girls, more often than boys, perceived their oral health to be good, except in the perception of the appearance of their teeth. Conclusions It is concluded that the strong associations between attitudes and self-perceived oral health should be recognised in strategies for oral health promotion and that gender differences must be considered.

2018201920202021202220232024 101001 - 101050 of 101516
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf