his.sePublications
Change search
Refine search result
199200201202203204205 10051 - 10100 of 10835
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • 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.
  • 10051.
    Törnblom, Kjell
    et al.
    University of Skövde, School of Technology and Society.
    Kazemi, Ali
    University of Skövde, School of Technology and Society.
    Some Conceptual and Theoretical Issues in Resource Theory of Social Exchange2012In: Handbook of social resource theory: theoretical extensions, empirical insights, and social applications / [ed] Kjell Törnblom, Ali Kazemi, New York: Springer, 2012, p. 33-64Chapter in book (Refereed)
    Abstract [en]

    This chapter by Törnblom and Kazemi discusses a number of issues in SRT which seem to benefit from further developments. Specifically, they ask whether the Foas’ resource classification meets the criteria for a typology, whether there are other dimensions than concreteness and particularism and whether the Foas’ six resource classes can be categorized into subclasses. Törnblom and Kazemi further discuss the validity of some of the exchange rules that the Foas formulated. They also extend the Foas’ two basic behavioral modes of giving and taking into four basic modes of exchange (i.e., giving-giving, giving-requesting, requesting-giving, and requesting-requesting), and this opens up for a host of further distinctions when additional facets like resource valence and resource type are included. Additional issues discussed in this chapter involve the production and acquisition of resources, different types of linkages between the production, acquisition, possession, and provision of resources, and finally the relevance of SRT to the topics of social justice, social exclusion, well-being, social dilemmas, social comparisons, and volunteering. Some of these issues are the focus of several chapters in this handbook.

  • 10052.
    Törnblom, Kjell
    et al.
    University of Skövde, School of Technology and Society.
    Kazemi, Ali
    University of Skövde, School of Technology and Society.
    The relative importance of outcome and procedure for total justice judgments2009In: Dynamics Within and Outside the Lab: Proceedings from the 6th GRASP conference, Lund University, May 2008 / [ed] Stefan Jern & Johan Näslund, Lund: Lund University , 2009, p. 184-202Conference paper (Refereed)
    Abstract [en]

    Contemporary justice theorists assume that a meaningful assessment of fairness in interpersonal encounters requires assessments of the outcome (the end result) as well as the procedure (the means) by which the outcome was accomplished. This study investigated the relative impact of four variables on the subjective importance of the outcome and procedure for total fairness evaluations, using a 2x2x2x2 factorial survey design: Type of offense (physical abuse vs. theft) x Severity of offense (moderate vs. serious) x Social relationship (particularistic vs. universalistic) x Status of the perpetrator relative to the victim (equal vs. superior). Results suggest that the outcome is considered more important than the procedure for fairness judgments of both offenses, regardless of their severity, relative status of the offender, and the social relationship within which the offense was committed. Furthermore, both outcome and procedure were viewed as more important when assessing the fairness of physical abuse as compared to theft. For the physical abuse offense, this was more likely to be the case when the status of the offender was superior to the status of the victim.

  • 10053.
    Törnblom, Kjell
    et al.
    University of Skövde, School of Technology and Society.
    Kazemi, Ali
    University of Skövde, School of Technology and Society.
    Toward a Resource Production Theory of Distributive Justice2007In: Distributive and procedural justice: research and social applications, Aldershot: Ashgate, 2007, p. 39-66Chapter in book (Other academic)
  • 10054.
    Törnblom, Kjell
    et al.
    University of Skövde, School of Technology and Society.
    Vermunt, RiëlUniversity of Skövde, School of Technology and Society.
    Distributive and procedural justice: research and social applications2007Collection (editor) (Other academic)
  • 10055.
    Törnblom, Kjell Y.
    et al.
    University of Skövde, School of Technology and Society.
    Kazemi, Ali
    University of Skövde, School of Technology and Society.
    Social Justice Research: Mission, Some Prospects, and Challenges2011In: Social Justice Research, ISSN 0885-7466, E-ISSN 1573-6725, Vol. 24, no 1, p. 1-5Article in journal (Refereed)
  • 10056.
    Törnblom, Kjell Y.
    et al.
    University of Skövde, School of Technology and Society.
    Vermunt, Riël
    University of Skövde, School of Technology and Society.
    Towards an Integration of Distributive Justice, Procedural Justice, and Social Resource Theories2007In: Social Justice Research, ISSN 0885-7466, E-ISSN 1573-6725, Vol. 20, no 3, p. 312-335Article in journal (Refereed)
    Abstract [en]

    The aim of this paper is to formulate new and more precise predictions regarding behavioral reactions to distributive and procedural injustice via insights from resource theory. The three theories share focus on discrepancies between actual and ideal states of existence as well as on psychological and behavioral reactions to discrepancy. But they also differ from each other in their conceptualizations and theorizing about these matters. Equity theory conceptualizes discrepancy as a perceived mismatch between inputs and outcomes; multiprinciple distributive justice and procedural justice theories view discrepancy as a mismatch between expected and applied distribution and procedural rules, respectively. Resulting feelings of inequity/injustice may trigger attempts to restore justice. Within the framework of resource theory, discrepancy concerns an inappropriate match between the nature of the provided and received resources. This leads to frustration which, in turn, may trigger attempts at retaliation. Limitations of the theories are discussed, with particular focus on their inability to match specific discrepancies with appropriate behavioral reactions. Behavioral predictions are based upon established congruence between behavioral reactions and violated procedural rules as well as type of inequity, as determined via their respective resource isomorphism. Limitations of the present integration attempt are discussed.

  • 10057.
    Törnqvist-Roos, Michaela
    University of Skövde, School of Life Sciences.
    Anhörigas upplevelser av att leva med en person som lider av bipolär sjukdom2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Bipolär sjukdom är en livslång sjukdom och livet tar en stor vändning, både för de somdrabbas samt de anhöriga. Det är av stor vikt för en sjuksköterska att kunna hantera ochstödja de anhöriga på ett bra sätt och genom att förstå de anhörigas upplevelser kan ettbättre stöd ges. Syftet med studien var att beskriva anhörigas upplevelser av att leva meden person som lider av bipolär sjukdom. Studien är litteraturbaserad och sju vetenskapligaartiklar har analyserats. Resultatet visade att de anhöriga upplevde att det dagliga livetpåverkas på olika sätt. Det visade också att behovet av kunskap om sjukdomen var stor,med hjälp av information ökade förmågan att klara av stress hos de anhöriga. De anhörigaupplevde även att det fanns ett behov av stöd framförallt ifrån professionella vårdgivare.Resultatet av studien kan bidra till en ökad förståelse hos sjuksköterskor angående deanhörigas upplevelser, känslor och behov av stöd, vilket i sin tur kan leda till att vården förden sjuke och dennes anhöriga blir bättre.

  • 10058.
    Ubbink, Marcellus
    et al.
    Leiden University.
    Ejdebäck, Mikael
    Göteborgs universitet.
    Crowley, Peter B.
    Schlarb, B. G.
    Howe, C. J.
    Karlsson, B. G.
    Bendall, D. S.
    Canters, G. W.
    The transient complex of the redox proteins cytochrome f and plastocyanin studied by NMR1999In: Journal of Inorganic Biochemistry, ISSN 0162-0134, E-ISSN 1873-3344, Vol. 74, no 1-4, p. 321-Article in journal (Other academic)
  • 10059.
    Ubbink, Marcellus
    et al.
    Department of Biochemistry and Cambridge Centre for Molecular Recognition, University of Cambridge, England / Leiden Institute of Chemistry, Leiden University, Gorlaeus Laboratories, The Netherlands.
    Ejdebäck, Mikael
    Department of Biochemistry and Biophysics, Göteborg University, Sweden / Chalmers University of Technology, Lundbergslaboratoriet, Göteborg, Sweden.
    Karlsson, B. Göran
    Department of Biochemistry and Biophysics, Göteborg University, Sweden / Chalmers University of Technology, Lundbergslaboratoriet, Göteborg, Sweden.
    Bendall, Derek S.
    Department of Biochemistry and Cambridge Centre for Molecular Recognition, University of Cambridge, England.
    The structure of the complex of plastocyanin and cytochrome f, determined by paramagnetic NMR and restrained rigid-body molecular dynamics1998In: Structure, ISSN 0969-2126, E-ISSN 1878-4186, Vol. 6, no 3, p. 323-335Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: The reduction of plastocyanin by cytochrome f is part of the chain of photosynthetic electron transfer reactions that links photosystems II and I. The reaction is rapid and is influenced by charged residues on both proteins. Previously determined structures show that the plastocyanin copper and cytochrome f haem redox centres are some distance apart from the relevant charged sidechains, and until now it was unclear how a transient electrostatic complex can be formed that brings the redox centres sufficiently close for a rapid reaction.

    RESULTS: A new approach was used to determine the structure of the transient complex between cytochrome f and plastocyanin. Diamagnetic chemical shift changes and intermolecular pseudocontact shifts in the NMR spectrum of plastocyanin were used as input in restrained rigid-body molecular dynamics calculations. An ensemble of ten structures was obtained, in which the root mean square deviation of the plastocyanin position relative to cytochrome f is 1.0 A. Electrostatic interaction is maintained at the same time as the hydrophobic side of plastocyanin makes close contact with the haem area, thus providing a short electron transfer pathway (Fe-Cu distance 10.9 A) via residues Tyr1 or Phe4 (cytochrome f) and the copper ligand His87 (plastocyanin).

    CONCLUSIONS: The combined use of diamagnetic and paramagnetic chemical shift changes makes it possible to obtain detailed information about the structure of a transient complex of redox proteins. The structure suggests that the electrostatic interactions 'guide' the partners into a position that is optimal for electron transfer, and which may be stabilised by short-range interactions.

  • 10060.
    Udayangani, Akwaththage
    University of Skövde, School of Bioscience.
    Facial age and anger expression: An event-related brain potential study2019Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The perception of human faces is affected by different facial features. For example, older faces are processed differently to younger ones and faces expressing diverse emotions are also processed differently. Research shows that angry faces are more attended to compared to neutral or other expressive faces, which is known as the ‘threat advantage’. This is evidenced by research on the late positive potential (LPP). The LPP is an event-related potential (ERP) component associated with affective processing, which seems to strongly respond to threats. The literature has indicated that older faces can elicit larger LPPs compared to young and neutral faces, and the LPP is more sensitive to emotional faces. The current experiment investigated subjective ratings in addition to the LPP in response to neutral and angry faces of young and old individuals, to examine how facial age influences the perception of anger. In a facial rating task, both the young and the old angry faces were rated as threatening faces, while old neutral faces were indicated to be more threatening than young neutral faces. Similarly, participants had a higher LPP for old angry faces. This data, in combination, suggests a higher emotional salience of old angry faces compared to either young angry or (young or old) neutral faces.

  • 10061.
    Uddgren, Jacqueline
    et al.
    University of Skövde, School of Life Sciences.
    Vare, Eva
    University of Skövde, School of Life Sciences.
    Skolsköterskors åtgärder för att förebygga och behandla skolbarn med stickrädsla vid vaccination2012Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Having a vaccination can, for the child, be a difficult experience. In case of the child having afear of needles the experience becomes even more difficult. The school nurse gives some ofthe vaccinations included in the national program of vaccinations as the National board ofhealth and welfare (2004) have established. In this study, the measures made by school nursesto facilitate the vaccination situation as far as possible, are illuminated. To implementinterviews with six school nurses and thereby receiving interview material, later analysedaccording to qualitative content analysis, could this subject be illuminated. The resultreceived, was school nurses giving schoolchildren support and security through motivationalwork. Information was a significant part of the measures made by the school nurses.Individual conversations and the providing of extra time for children with a particular needlephobia was a measure aswell. Through care that could be given through playing and learning,school nurses could provide safety which was crucial at the time of the vaccination. Toprevent fear of needles, a school nurse has to be given the time required for these preventingmeasures. This preventing work will reduce the risk that the schoolchildren will have a fear ofneedles if care is needed later on as children or as adults.

  • 10062.
    Uddqvist, Anette
    et al.
    University of Skövde, School of Technology and Society.
    Roberthson, Ida
    University of Skövde, School of Technology and Society.
    Improvement of sampling system for Remote Explosive Scent Tracing2010Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Remote Explosives Scent Tracing (REST) is the concept of bringing the mine field to Mine Detection Dogs or Rats, instead of vice versa. This is done by collecting air or dust from minefields, and taking these samples to a laboratory environment, where they are subsequently analysed by the detection animals.

    REST has previously proven to be very fast and cost effective, but one of the issues facing the method is that there is yet no reliable tool for sampling dust. In earlier sampling units, air has been collected in filters. However, the concentration of scents related to mines has been seen to be a million times higher in dust particles than in air sampled from above the ground. The aim of this project was to evaluate and improve a dust sampling prototype constructed in the beginning of 2010. The project was initiated in cooperation with the GICHD (Geneva International Centre for Humanitarian demining), and carried out in cooperation with APOPO (Anti-Personnel Landmines Detection Product Development).

    During this project, information was gathered on the samplers that have previously been used for REST. A new prototype was made in Trondheim in cooperation with NTNU (Norwegian University of Science and Technology). With this new sampler prototype, tests were made in a laboratory environment at NTNU as well as at APOPO’s test mine field in Morogoro, Tanzania. Several obstacles were faced, such as difficulties to test and evaluate the sampler during the rainy season, insufficient air supply for the prototype, and issues with the laboratory equipment in Morogoro. Due to this, the number of tests performed and the number of repetitions of each test was not as high as would have been desired.

    The results of the information gathering and the tests are presented in this report, and the knowledge and experience gained resulted in several suggestions for improvements for the sampler prototype. A suggestion for a grid design that would cover the entire mouth piece, with a built-in distance to the suction inlet, in order to avoid both clogging of the grid and that too much dust is sucked in if the mouth piece touches the ground and a fully adjustable sampling unit. Several other recommendations are given that would reduce cross contamination risks and improve ergonomics and other aspects of the sampler prototype.

  • 10063.
    Udhane, Sameer
    University of Skövde, School of Life Sciences.
    In Situ PLA image analysis using Blob Finder tool for evaluation of protein interaction2010Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In recent biomedical research, images are generated at the high rates by using modern fluorescence microscopy. There are different image analysis software that can be used to perform a wide array of useful image analysis measurement. The identification of protein interaction is important for the detail study of localization and quantification of the expression. The main aim of the project was to evaluate the interactions of FUS/Plectin proteins in fibrosarcoma cells using the Blobfinder tool. The FUS/Plectin interaction localization was showed using In Situ Proximity ligation based assay (PLA) and these protein interactions were quantified by the Blobfinder tool. The obtained quantitative results from the tool were statistically analyzed by Graphpad prism software and Microsoft Excel. PLA results showed the localization of the FUS/Plectin interaction in the cytoplasm and on the border of nucleus. The Blobfinder tool obtained quantitative results which suggested that there were more interactions in the cytoplasm as compare to the nucleus. The histogram analysis also suggests that the frequency of interactions were higher in the cytoplasm when compared to nucleus in majority of cells. The obtained results from the Blobfinder tool and In situ PLA are in agreement with the results obtained from Immunoprecipitation pull down assay which shows FUS/Plectin interactions.

  • 10064.
    Udén, Emelie
    et al.
    University of Skövde, School of Engineering Science.
    Westerberg, Sara
    University of Skövde, School of Engineering Science.
    Utveckling av hygienisk golvränna2017Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    AB Furhoffs Rostfria was founded in Skövde in 1899 to produce pots and cauldrons in copper. Today´s production is focused on products for HVAC (heating, ventilation and air conditioning) as well as for restaurant kitchens and customized products. The production is located in Skövde with machines suited for processing stainless steel.

    Demands from the market as well as Furhoff´s competitors are focusing on hygienic floor drain gutters. Because of this, Furhoffs wants to be the leading company of this kind of development. This project aims to develop a floor drain gutter that is suitable for environments with high requirements of hygiene to prevent spreading of diseases. These environments can be food factories, laboratories, hospitals and restaurant kitchens. The product needs to be safe to use in industries where traffic from heavy vehicles occur. This means that the product must withstand a load of 12 500 kg.

    To adjust the product to fit the user, interviews were performed in a large dairy, a food factory and in a restaurant. An observation was also performed in the restaurant to observe the cleaning process of a floor drain gutter. The information from the user study resulted in a list of needs. These, combined with demands from the company, formed the product specification. This specification was the basis for how the product later was developed. The components of the floor drain gutter, gully with a stench trap, gutter, cover and strainer basket, was developed separately and adapted to each other. Tests and cost analysis were performed to make well-founded concept choices. Water flow and removal of waste was tested to choose the most optimal gutter profile. To make sure the floor drain gutter is safe to use in the intended environment, load tests, slip tests and tests of flow rates were made.   

    The final product is adjusted for Furhoff´s production methods. The floor drain gutter fulfils the requirements and is suitable for environments with high hygiene demands. The result from this thesis will be used for further development of Furhoff´s future floor drain gutter. 

  • 10065.
    Ujvari, Sandor
    University of Skövde, School of Technology and Society.
    Deregulation of Railroads and Future Development Scenarios in Europe: A Literature Analysis of the Privatization Process taken place in US, UK and Sweden2006In: NOFAM 2006: 18th annual NOFAM conference Logistics in the new valley, Norwegian School of Management, 2006Conference paper (Refereed)
  • 10066.
    Ujvari, Sandor
    University of Skövde, School of Technology and Society. University of Skövde, The Virtual Systems Research Centre.
    Proceedings of the Plan Research Conference2010Conference proceedings (editor) (Other academic)
  • 10067.
    Ujvari, Sandor
    et al.
    University of Skövde, School of Technology and Society.
    Hilmola, Olli-Pekka
    Kouvola Research Unit, Lappeenranta University of Technology, Kouvola, Finland.
    Advanced manufacturing simulation: Minor system details can be major issues in the real world2006In: Industrial management + data systems, ISSN 0263-5577, E-ISSN 1758-5783, Vol. 106, no 8, p. 1166-1186Article in journal (Refereed)
    Abstract [en]

    Purpose – This paper aims to highlight the complex nature of automated guided vehicle (AGV) simulation model building, and especially how system modelling details affect the end results. This is an important issue in all of the transportation simulation systems, since they are service-based by their nature, and additional inefficiencies create unanticipated performance downgrading.

    Design/methodology/approach – This paper uses a simulation approach, and simulated systems are based on a real-life case study and on well accepted hypothetical simulation example.

    Findings – Simulation system boundaries are often neglected in the model building, and especially interface to inbound (and possibly outbound) material flow should be considered carefully; based on these research results, AGV investments are seen in an entirely different light, as system boundary is enlarged to contain more realistically interacting elements. Similar system boundary issues were found from the case study: interface with overhead gantry did not provide near optimal performance. The case study also revealed that high speed of AGVs is not necessarily worth additional investment; constraints exist in safety, acceleration and ability to turn in corners.

    Research limitations/implications – The findings are based on the simulation work and, to see the real implications, real-life implementations on policy level are needed.

    Practical implications – Results of this research provide more insights for manufacturing unit investments, and especially in the scope of automated transportation system use. Also changes in manufacturing flow management issues, after investing in, for example, AGV systems, are different from in less-automated manufacturing units.

    Originality/value – This research work provides more insights to simulation research work, especially from the perspective of transportation systems. Also implications arising from case study are unique as being compared to previous research in the field.

  • 10068.
    Ujvari, Sandor
    et al.
    University of Skövde, The Virtual Systems Research Centre. University of Skövde, School of Technology and Society.
    Hilmola, Olli-Pekka
    Kouvola Research Unit, Lappeenranta University of Technology, Kouvola, Finland.
    Semi-autonomous vehicles with routing flexibility: functionality and application areas2009In: International Journal of Services and Operations Management, ISSN 1744-2370, Vol. 5, no 4, p. 444-462Article in journal (Refereed)
    Abstract [en]

    Automated Guided Vehicle (AGV) systems are standard automated items in production and warehousing today. However, studies have rarely examined a more advanced form of AGVs called Semi-Autonomous Vehicles (SAVs), which have a higher sophistication of task completion and routing flexibility. This research presents SAVs in an industrial development case study. Using simulation, the route-keeping ability of SAVs with two types of guidance techniques is being studied. The results show that dual-navigation SAVs can provide the needed flexibility for routing. Using wire guidance and dead reckoning, both very well-established techniques, the SAVs' performance is, within certain limits, quite comparable to the AGVs with more advanced and expensive navigation techniques.

  • 10069.
    Ujvari, Sandor
    et al.
    University of Skövde, School of Technology and Society.
    Hilmola, Olli-pekka
    Kouvola Research Unit, Lappeenranta University of Technology, Kouvola, Finland.
    Simulation of Automatic Guided Vehicle systems in manufacturing environment: Case: Volvo's Crankshaft Unit in Skovde2008In: International Journal of Manufacturing Technology and Management (IJMTM), ISSN 1368-2148, E-ISSN 1741-5195, Vol. 15, no 1, p. 45-63Article in journal (Refereed)
    Abstract [en]

    Competing in global markets creates pressure for manufacturers to rigidly use automation, and advanced manufacturing techniques to improve manufacturing plant productivity. Among productivity, manufacturers are also interested about other performance dimensions, namely time, flexibility and quality. With the wise use of automation, we could directly improve all of the other indicators, and indirectly quality. In this paper it is shown, how implementation and use of Automatic Guided Vehicles (AGVs) could benefit from the use of manufacturing simulation. AGVs have been available for practical use since the 1970s, but still in the investment and use processes it is rarely seen justified to a high detail, what eventually determines the number of vehicles used in the system. Our paper is able to show with two simulation cases (a hypothetical example and a real case study) that the number of AGVs is very sensitive with respect to production system output. Furthermore, some assumptions that are often made can overly simplify the problem (e.g. no recharging of batteries and constant speed). Therefore, in this paper, we propose that more research should be addressed to the AGV system simulation, and in practice tools for decisions makers should be developed further. Our research also shows that empty travelling and low utilisation is a norm in current AGV systems in order to assure production system functionality, and there is a need and potential for performance improvement here, as well.

  • 10070.
    Uleander, Daniel
    University of Skövde, School of Humanities and Informatics.
    Känslouttryck i döda ting: Studie hur känslouttryck kan överföras till en rekvisitas form och uppfattas av betraktare2010Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Detta arbete redovisar hur fysiska kännetecken för mänskliga känslouttryck, utan andra mänskliga attribut, överförs till rekvisita och uppfattas av betraktare. Kunskap i hur känslor blir till uttryck, är hämtat från boken Unmasking the face. En byrå, soffa och säng valdes till att uttrycka känslorna. Genom att tänka i animation och rörelse, skapades tolv modeller för känslouttrycken glädje, ilska, rädsla och förvåning. Möblerna och deras känslouttryck tecknades för att slutligen modelleras. Problemställningen besvarades genom en enkätundersökning i Skövde centrum på fyrtiotvå slumpmässigt utvalda personer.

    Glädje, ilska och förvåning uppfattades av majoriteten, även om förvåning var otydligare. Rädsla uppfattades av en mindre del. Generellt uppfattades rädsla som förvåning eller vemod.

    Examensarbetets syfte är att skapa underlag till att fortsättningsvis använda känslouttryck i döda ting. Exempelvis kommunicera känslor i terapeutiskt verktyg, dataspel eller andra mediala sammanhang. 

  • 10071.
    Ulfat, I.
    et al.
    Department of Physics, University of Karachi, Pakistan.
    Kanski, J.
    Chalmers University of Technology, Göteborg, Sweden.
    Ilver, L.
    Chalmers University of Technology, Göteborg, Sweden.
    Sadowski, J.
    MAX-IV laboratory, Lund University, Sweden.
    Karlsson, Krister
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Ernst, A.
    Max-Planck-Institut für Mikrostrukturphysik, Halle, Germany / Wilhelm-Ostwald-Institut für Physikalische und Theoretische Chemie, Universität Leipzig, Germany.
    Sandratskii, L.
    Max-Planck-Institut für Mikrostrukturphysik, Halle, Germany.
    Effects of nonuniform Mn distribution in (Ga,Mn)As2014In: Physical Review B Condensed Matter, ISSN 0163-1829, E-ISSN 1095-3795, Vol. 89, no 4, p. 1-5, article id 045312Article in journal (Refereed)
    Abstract [en]

    Resonant in situ photoemission from Mn 3d states in Ga(1−x)MnxAs is reported for Mn concentrations down to the very dilute level of 0.1%. Concentration-dependent spectral features are analyzed on the basis of first-principles calculations for systems with selected impurity positions as well as for random alloys. Effects of direct Mn-Mn interaction are found for concentrations as low as 2.5%, and are ascribed to statistical (nonuniform) distribution of Mn atoms.

  • 10072.
    Ulfberg, Nina
    et al.
    University of Skövde, School of Health and Education.
    Wibergh, Sandra
    University of Skövde, Health and Education.
    Att främja mental hälsa genom fysisk aktivitet: En litteraturstudie2014Independent thesis Basic level (university diploma), 5 credits / 7,5 HE creditsStudent thesis
  • 10073.
    Ulfenborg, Benjamin
    University of Skövde, School of Bioscience. University of Skövde, The Systems Biology Research Centre.
    Bioinformatics tools for discovery and evaluation of biomarkers: Applications in clinical assessment of cancer2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Cancer is a disease characterized by abnormal proliferation of cells in the body and ranks as the second leading cause of death worldwide. In order to improve cancer patient care, a major focus of cancer research is to discover biomarkers. A biomarker is a biological molecule found in tissues or body fluids and can be used to predict or assess disease states. The aim of this thesis is to develop bioinformatics tools for discovery and evaluation of novel biomarkers from high-throughput datasets.

    MicroRNAs (miRNAs) are short non-coding RNAs that function as negative regulators of gene expression. Dysregulation of miRNAs in cancer is frequently reported, making them interesting as biomarker candidates. GenoScan was developed for genome-wide discovery of miRNA-coding genes, as a first step in the identification of novel mi-RNA biomarkers.

    High-throughput technologies such as microarrays allow researchers to measure the expression of thousands of genes or miRNAs simultaneously. The Decision Trunk Classifier (DTC) algorithm has been developed to screen datasets from these experiments for biomarker candidates. When applied to a miRNA expression dataset for endometrial cancer (EC) samples vs. controls, a two-marker model with 98 % accuracy was generated. These miRNAs (hsa-miR-183-5p and hsa-miRPlus-C1070) are promising as biomarkers for EC screening.

    The miREC database was developed to store gene and miRNA data from curated expression profiling studies of EC, as well as gene-miRNA regulatory connections. Using gene-miRNA interaction networks from miREC, the roles of miRNAs in cancer hallmark acquisition can be clarified. To further support exploratory analysis of expression data, DTC was extended with partial least squares regression models. The resulting PLS-DTC algorithm can be used to gain deeper insights into the perturbation of biological processes and pathways.

  • 10074.
    Ulfenborg, Benjamin
    University of Skövde, School of Life Sciences.
    Investigation of the implications of nitric oxide on biofilm development2008Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Biofilms are communities of sessile microorganisms attached to a surface and imbeddedin a matrix of extracellular polysaccharide substances. These communities can be foundin diverse aquatic environments, such as in industrial pipes and in humans. By formingmicrocolony structures, which are highly resistant to adverse physical conditions as wellas antimicrobial agents, biofilms are very problematic when associated with e.g.persistent infections. In order to find new ways of controlling biofilm growth, theprocesses involved in biofilm development must be investigated further. The maininterest of this study is the occurrence of void formation inside biofilms. Thisphenomenon has been observed in several studies and has been correlated to cell deathinside the microcolonies. The occurrence of cell death has recently been associated withthe presence of nitric oxide in the biofilm. In this study, the implications of nitric oxideaccumulation on biofilm development were investigated using an individual-basedmodel. Specifically, the role of nitric oxide in void formation was considered. A largenumber of simulations were run using different parameter settings in order to determine ifnitric oxide could account for the occurrence of void formation observed experimentally.The general predictions made by the model system showed agreement to someexperimental data, but not to others. Sloughing, the detachment of chunks of cells fromthe biofilm, was observed in the majority of simulations. In some cases, the model alsopredicted the presence of live cells inside the voids, which has been observedexperimentally.

  • 10075.
    Ulfenborg, Benjamin
    University of Skövde, School of Bioscience. University of Skövde, The Systems Biology Research Centre.
    Vertical and horizontal integration of multi-omics data with miodin2019In: BMC Bioinformatics, ISSN 1471-2105, E-ISSN 1471-2105, Vol. 20, no 649Article in journal (Refereed)
    Abstract [en]

    Background: Studies on multiple modalities of omics data such as transcriptomics, genomics and proteomics are growing in popularity, since they allow us to investigate complex mechanisms across molecular layers. It is widely recognized that integrative omics analysis holds the promise to unlock novel and actionable biological insights into health and disease. Integration of multi-omics data remains challenging, however, and requires combination of several software tools and extensive technical expertise to account for the properties of heterogeneous data.

    Results: This paper presents the miodin R package, which provides a streamlined workflow-based syntax for multi-omics data analysis. The package allows users to perform analysis of omics data either across experiments on the same samples (vertical integration), or across studies on the same variables (horizontal integration). Workflows have been designed to promote transparent data analysis and reduce the technical expertise required to perform low-level data import and processing.

    Conclusions: The miodin package is implemented in R and is freely available for use and extension under the GPL-3 license. Package source, reference documentation and user manual are available at https://gitlab.com/algoromics/miodin.

  • 10076.
    Ulfenborg, Benjamin
    et al.
    University of Skövde, School of Bioscience. University of Skövde, The Systems Biology Research Centre.
    Jurcevic, Sanja
    University of Skövde, School of Bioscience. University of Skövde, The Systems Biology Research Centre.
    Lindelöf, Angelica
    University of Skövde, School of Bioscience. University of Skövde, The Systems Biology Research Centre.
    Klinga-Levan, Karin
    University of Skövde, School of Bioscience. University of Skövde, The Systems Biology Research Centre.
    Olsson, Björn
    University of Skövde, School of Bioscience. University of Skövde, The Systems Biology Research Centre.
    miREC: a database of miRNAs involved in the development of endometrial cancer2015In: BMC Research Notes, ISSN 1756-0500, E-ISSN 1756-0500, Vol. 8, no 1, article id 104Article in journal (Refereed)
    Abstract [en]

    Background

    Endometrial cancer (EC) is the most frequently diagnosed gynecological malignancy and the fourth most common cancer diagnosis overall among women. As with many other forms of cancer, it has been shown that certain miRNAs are differentially expressed in EC and these miRNAs are believed to play important roles as regulators of processes involved in the development of the disease. With the rapidly growing number of studies of miRNA expression in EC, there is a need to organize the data, combine the findings from experimental studies of EC with information from various miRNA databases, and make the integrated information easily accessible for the EC research community.

    Findings

    The miREC database is an organized collection of data and information about miRNAs shown to be differentially expressed in EC. The database can be used to map connections between miRNAs and their target genes in order to identify specific miRNAs that are potentially important for the development of EC. The aim of the miREC database is to integrate all available information about miRNAs and target genes involved in the development of endometrial cancer, and to provide a comprehensive, up-to-date, and easily accessible source of knowledge regarding the role of miRNAs in the development of EC. Database URL: http://www.mirecdb.orgwebcite.

    Conclusions

    Several databases have been published that store information about all miRNA targets that have been predicted or experimentally verified to date. It would be a time-consuming task to navigate between these different data sources and literature to gather information about a specific disease, such as endometrial cancer. The miREC database is a specialized data repository that, in addition to miRNA target information, keeps track of the differential expression of genes and miRNAs potentially involved in endometrial cancer development. By providing flexible search functions it becomes easy to search for EC-associated genes and miRNAs from different starting points, such as differential expression and genomic loci (based on genomic aberrations).

  • 10077.
    Ulfenborg, Benjamin
    et al.
    University of Skövde, School of Bioscience. University of Skövde, The Systems Biology Research Centre.
    Karlsson, Alexander
    University of Skövde, School of Informatics. University of Skövde, The Informatics Research Centre.
    Riveiro, Maria
    University of Skövde, School of Informatics. University of Skövde, The Informatics Research Centre.
    Améen, Caroline
    Takara Bio Europe AB, Gothenburg, Sweden.
    Åkesson, Karolina
    Takara Bio Europe AB, Gothenburg, Sweden.
    Andersson, Christian X.
    Takara Bio Europe AB, Gothenburg, Sweden.
    Sartipy, Peter
    University of Skövde, School of Bioscience. University of Skövde, The Systems Biology Research Centre. Cardiovascular and Metabolic Disease Global Medicines Development Unit, AstraZeneca, Mölndal, Sweden.
    Synnergren, Jane
    University of Skövde, School of Bioscience. University of Skövde, The Systems Biology Research Centre.
    A data analysis framework for biomedical big data: Application on mesoderm differentiation of human pluripotent stem cells2017In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 12, no 6, article id e0179613Article in journal (Refereed)
    Abstract [en]

    The development of high-throughput biomolecular technologies has resulted in generation of vast omics data at an unprecedented rate. This is transforming biomedical research into a big data discipline, where the main challenges relate to the analysis and interpretation of data into new biological knowledge. The aim of this study was to develop a framework for biomedical big data analytics, and apply it for analyzing transcriptomics time series data from early differentiation of human pluripotent stem cells towards the mesoderm and cardiac lineages. To this end, transcriptome profiling by microarray was performed on differentiating human pluripotent stem cells sampled at eleven consecutive days. The gene expression data was analyzed using the five-stage analysis framework proposed in this study, including data preparation, exploratory data analysis, confirmatory analysis, biological knowledge discovery, and visualization of the results. Clustering analysis revealed several distinct expression profiles during differentiation. Genes with an early transient response were strongly related to embryonic-and mesendoderm development, for example CER1 and NODAL. Pluripotency genes, such as NANOG and SOX2, exhibited substantial downregulation shortly after onset of differentiation. Rapid induction of genes related to metal ion response, cardiac tissue development, and muscle contraction were observed around day five and six. Several transcription factors were identified as potential regulators of these processes, e.g. POU1F1, TCF4 and TBP for muscle contraction genes. Pathway analysis revealed temporal activity of several signaling pathways, for example the inhibition of WNT signaling on day 2 and its reactivation on day 4. This study provides a comprehensive characterization of biological events and key regulators of the early differentiation of human pluripotent stem cells towards the mesoderm and cardiac lineages. The proposed analysis framework can be used to structure data analysis in future research, both in stem cell differentiation, and more generally, in biomedical big data analytics.

  • 10078.
    Ulfenborg, Benjamin
    et al.
    University of Skövde, School of Life Sciences. University of Skövde, The Systems Biology Research Centre.
    Klinga-Levan, Karin
    University of Skövde, School of Life Sciences. University of Skövde, The Systems Biology Research Centre.
    Olsson, Björn
    University of Skövde, School of Life Sciences. University of Skövde, The Systems Biology Research Centre.
    Classification of tumor samples from expression data using decision trunks2013In: Cancer Informatics, ISSN 1176-9351, E-ISSN 1176-9351, Vol. 12, p. 53-66Article in journal (Refereed)
    Abstract [en]

    We present a novel machine learning approach for the classification of cancer samples using expression data. We refer to the method as "decision trunks," since it is loosely based on decision trees, but contains several modifications designed to achieve an algorithm that: (1) produces smaller and more easily interpretable classifiers than decision trees; (2) is more robust in varying application scenarios; and (3) achieves higher classification accuracy. The decision trunk algorithm has been implemented and tested on 26 classification tasks, covering a wide range of cancer forms, experimental methods, and classification scenarios. This comprehensive evaluation indicates that the proposed algorithm performs at least as well as the current state of the art algorithms in terms of accuracy, while producing classifiers that include on average only 2-3 markers. We suggest that the resulting decision trunks have clear advantages over other classifiers due to their transparency, interpretability, and their correspondence with human decision-making and clinical testing practices. © the author(s), publisher and licensee Libertas Academica Ltd.

  • 10079.
    Ulfenborg, Benjamin
    et al.
    University of Skövde, School of Bioscience. University of Skövde, The Systems Biology Research Centre.
    Klinga-Levan, Karin
    University of Skövde, School of Bioscience. University of Skövde, The Systems Biology Research Centre.
    Olsson, Björn
    University of Skövde, School of Bioscience. University of Skövde, The Informatics Research Centre.
    Genome-wide discovery of miRNAs using ensembles of machine learning algorithms and logistic regression2015In: International Journal of Data Mining and Bioinformatics, ISSN 1748-5681, Vol. 13, no 4, p. 338-359Article in journal (Refereed)
    Abstract [en]

    In silico prediction of novel miRNAs from genomic sequences remains a challenging problem. This study presents a genome-wide miRNA discovery software package called GenoScan and evaluates two hairpin classification methods. These methods, one ensemble-based and one using logistic regression were benchmarked along with 15 published methods. In addition, the sequence-folding step is addressed by investigating the impact of secondary structure prediction methods and the choice of input sequence length on prediction performance. Both the accuracy of secondary structure predictions and the miRNA prediction are evaluated. In the benchmark of hairpin classification methods, the regression model achieved highest classification accuracy. Of the structure prediction methods evaluated, ContextFold achieved the highest agreement between predicted and experimentally determined structures. However, both the choice of secondary structure prediction method and input sequence length had limited impact on hairpin classification performance.

  • 10080.
    Ulfenborg, Benjamin
    et al.
    University of Skövde, School of Bioscience. University of Skövde, The Systems Biology Research Centre.
    Klinga-Levan, Karin
    University of Skövde, School of Bioscience. University of Skövde, The Systems Biology Research Centre.
    Olsson, Björn
    University of Skövde, School of Bioscience. University of Skövde, The Systems Biology Research Centre.
    GenoScan: Genomic Scanner for Putative miRNA Precursors2014In: Bioinformatics Research and Applications: 10th International Symposium, ISBRA 2014, Zhangjiajie, China, June 28-30, 2014. Proceedings / [ed] Mitra Basu, Yi Pan, Jianxin Wang, Springer, 2014, p. 266-277Conference paper (Refereed)
    Abstract [en]

    The significance of miRNAs has been clarified over the last decade as thousands of these small non-coding RNAs have been found in a wide variety of species. By binding to specific target mRNAs, miRNAs act as negative regulators of gene expression in many different biological processes. Computational approaches for discovery of miRNAs in genomes usually take the form of an algorithm that scans sequences for miRNA-characteristic hairpins, followed by classification of those hairpins as miRNAs or nonmiRNAs. In this study, two new approaches to genome-scale miRNA discovery are presented and evaluated. These methods, one ensemble-based and one using logistic regression, have been designed to detect miRNA candidates without relying on conservation or transcriptome data, and to achieve high-confidence predictions in reasonable computational time. GenoScan achieves high accuracy with a good balance between sensitivity and specificity. In a benchmark evaluation including 15 previously published methods, the regression-based approach in GenoScan achieved the highest classification accuracy.

  • 10081.
    Ulfström, Emil
    University of Skövde, School of Business.
    Medlemsbankernas riskhantering: med samhällsengagemang som ledstjärna2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In Sweden today there are two member banks, JAK Medlemsbank and Ekobanken. They differ from the Swedish commercial banks by looking at themselves and their role from a social perspective. Banking is associated with risks, mainly credit risk but also other risks. Banks' risk management becomes more and more technologically advanced. The study aims to contribute to greater understanding of how Sweden's member banks manage their risks compared to the commercial banks.

    Two theories of human models are presented; Homo Politicus, social man, and Homo Economicus, the rational profit-maximizing man. The different groups of banks differ in business logic and driving force which finds support in these two theories.

    The study makes a comparative analysis of data from three different collection methods. Both quantitative and qualitative methods are used to come to an accurate conclusion.

    The member banks are driven by a genuine social commitment and their CSR work is well integrated into everyday operations, while at the commercial banks are CSR efforts more besides banking. The member banks show an openness and this is a great addition to their liquidity buffers in a liquidity crisis. The commercial banks' risk analysis of credit based more closely on measurable quantitative factors than the member banks where there is a greater focus on qualitative factors. Although the tools of risk analysis differ member banks and the commercial banks. The commercial banks have centrally developed decision support as a base in its risk analysis while the member banks have a more manual handling. Basel III, the new regulations with stricter requirements for capital and liquidity requirements for banks have not had any negative impact on member banks, as their margins even before the introduction was better than the new stricter discipline. However, the increased workload on the new comprehensive regulatory framework affecting the member banks.

    That member banks can conduct banking activities from a social perspective rather than a more traditional profit-maximizing perspective can be explained by that bank customers accept the higher requirements from the banks, either in the form of collateral or savings alongside loans. This is possible because the member banks members, who is also a partner, are closer to the theory of Homo Politicus like member banks than Homo Economicus that the commercial banks are closer to.

  • 10082.
    Ullah, Naseem
    University of Skövde, School of Bioscience.
    Disease modules identification in heterogenous diseases with WGCNA method2019Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The widely collected and analyzed genetic data help in understanding the underlying mechanisms of heterogeneous diseases. Cellular components interact in a network fashion where genes are nodes and edges are the interactions. The failure in individual genes lead to dys-regulation of sub-groups of genes which causes a disease phenotype, and this dys-functional region is called a disease module. Disease module identification in complex diseases such as asthma and cancer is a huge challenge. Despite the development of numerous sophisticated methods there is a still no gold standard. In this study we apply different parameter settings to test the performance of a widely used method for disease module detection in multi-omics data called Weighted Gene Co-expression Network Analysis (WGCNA). A systematic approach is used to identify disease modules in asthma and arthritis diseases. The accuracy of obtained modules is validated by a pathway scoring algorithm (PASCAL) and GWAS SNP enrichment. Our results differ between the tested data sets and therefore we cannot conclude with recommendations for an optimal setting that could perform best for multiple data sets using this method.

  • 10083.
    Ulvestad, Maria
    et al.
    AstraZeneca, Sweden / Cellectis AB, Sweden / University of Oslo, Norway.
    Nordell, Pär
    AstraZeneca, Sweden.
    Asplund, Annika
    Cellectis AB, Sweden.
    Rehnström, Marie
    Cellectis AB, Sweden.
    Jacobsson, Susanna
    Cellectis AB, Sweden.
    Holmgren, Gustav
    University of Skövde, School of Life Sciences. University of Skövde, The Systems Biology Research Centre. Cellectis AB, Sweden / Sahlgrenska University Hospital, Sweden.
    Davidson, Lindsay
    University of Dundee, Scotland.
    Brolén, Gabriella
    AstraZeneca, Sweden.
    Edsbagge, Josefina
    Cellectis AB, Sweden.
    Björquist, Petter
    Cellectis AB, Sweden.
    Küppers-Munther, Barbara
    University of Skövde, School of Life Sciences. University of Skövde, The Systems Biology Research Centre. Cellectis AB, Sweden.
    Andersson, Tommy B.
    AstraZeneca, Sweden / Karolinska Institute, Sweden.
    Drug metabolizing enzyme and transporter protein profiles of hepatocytes derived from human embryonic and induced pluripotent stem cells2013In: Biochemical Pharmacology, ISSN 0006-2952, E-ISSN 1356-1839, Vol. 86, no 5, p. 691-702Article in journal (Refereed)
    Abstract [en]

    Human embryonic and induced pluripotent stem cell-derived hepatocytes (hESC-Hep and hiPSC-Hep) have the potential to provide relevant human in vitro model systems for toxicity testing and drug discovery studies. In this study, the expression and function of important drug metabolizing cytochrome P450 (CYP) enzymes and transporter proteins in hESC-Hep and hiPSC-Hep were compared to cryopreserved human primary hepatocytes (hphep) and HepG2 cells. Overall, CYP activities in hESC-Hep and hiPSC-Hep were much lower than in hphep cultured for 4 h, but CYP1A and 3A activities were comparable to levels in hphep cultured for 48 h (CYP1A: 35% and 26% of 48 h hphep, respectively; CYP3A: 80% and 440% of 48 h hphep, respectively). Importantly, in hESC-Hep and hiPSC-Hep, CYP activities were stable or increasing for at least one week in culture which was in contrast to the rapid loss of CYP activities in cultured hphep between 4 and 48 h after plating. With regard to transporters, in hESC-Hep and hiPSC-Hep, pronounced NTCP activity (17% and 29% of 4 h hphep, respectively) and moderate BSEP activity (6% and 8% of 4 h hphep, respectively) were observed. Analyses of mRNA expression and immunocytochemistry supported the observed CYP and transporter activities and showed expression of additional CYPs and transporters. In conclusion, the stable expression and function of CYPs and transporters in hESC-Hep and hiPSC-Hep for at least one week opens up the possibility to reproducibly perform long term and extensive studies, e.g. chronic toxicity testing, in a stem cell-derived hepatic system. (C) 2013 Elsevier Inc. All rights reserved.

  • 10084.
    Ulvstig, Kalle
    University of Skövde, Department of Computer Science.
    Systemutvecklares syn på användarcentrerad systemdesign2003Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [sv]

    Det talas ofta om hur viktigt det är att involvera användarna vid systemutveckling. Genom att använda användarcentrerad systemdesign kan det bidra till bättre system både ur teknisk- och användarsynpunkt. Det är av stor betydelse att de användare som tas ut vid användarcentrerad systemdesign representerar användargruppen. Användarcentrerad systemdesign är en process som fokuserar på användare och användbarhet genom hela utvecklingsprocessen och vidare genom hela livscykeln. Detta arbete syftar till att undersöka vilka kriterier som utvecklare använder sig av för att ta ut användare vid angreppssättet användarcentrerad systemdesign. Arbetet har genomförts genom en litteraturstudie och ett antal intervjuer.

  • 10085.
    Ulvö, Fredrik
    University of Skövde, School of Humanities and Informatics.
    Systemlösningsmigrationer till öppen källkod: En analys av utförda migrationsprojekt i offentliga förvaltningar sett utifrån ett riskperspektiv2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Den här studien bidrar till attöka kunskapen inom området systemlösningsmigrationer genomatt ta reda på vad som går att lära av tidigare genomförda migrationsprojekt. Studien genomförs genom att utföra fallstudier på avrapporterade migrationsprojekt som har utfört en migration från att använda proprietära systemlösningar till att använda systemlösningar baserade på öppen källkod. Efter en urvalsprocess kvarstod tre migrationsprojekt aktuella för analys utifrån ett riskperspektiv. Det var migrationsprojektet LiMux i Tyskland,ett projekt inom det franska gendarmeriet och ett projekt som utfördes bland skolorna i Bolzanoprovinsen i Italien.

    Resultatet av studien visar bland annat att alla tre migrationsprojekten upplevde risken att inte kunna ta egna IT-beslut före den utförda migrationen. Detta berodde på att de före migrationen använde sig av proprietära systemlösningar, vilka de upplevt varit orsaken till detta. Den här risken säger de sig nu ha kunnat undvika genom att använda systemlösningar baserade på öppen källkod. De risker som förvaltningarna upplevt efter utförd migration kan sammanfattas med att det är risker som medför kortsiktiga problem för förvaltningarna. De räknar med att riskerna kommer att minska och problem kommer att lösas allt eftersom tiden går. Till exempel upplevde de att de har varit tvungna att anlita extern support för att lösa tekniska frågor relaterade till den nya systemlösningen. De säger dock att de i framtiden räknar med att själva ansvara för supporten när personalens kompetens har höjts inom förvaltningarna.

    Studien visar också att en modell, BRW Migration Model for desktop OSS, kan användas för att minska riskerna vid en migrationsprocess. Detta görs genom att följa de nio steg som modellen beskriver som viktiga för en lyckad migrationsprocess.

  • 10086.
    Unger, Liza
    University of Skövde, Department of Computer Science.
    OMT och Objectory: vilka synpunkter har några svenska utvecklingsföretag på dessa metoder idag?1998Independent thesis Basic level (degree of Bachelor)Student thesis
    Abstract [sv]

    Objektorientering har kommit att bli en väletablerad teknik inom systemutvecklingen. De fördelar som den objektorienterade tekniken anses medföra är bl a att den ger en mer användarnära systemutveckling och ökar produktiviteten genom återanvändning av komponenter. Men det har även riktats kritik mot den objektorienterade tekniken. Ett område som har kritiserats är de objektorienterade metoderna. De har uppfattats som instabila och ofullständiga i början av 90-talet då de var nya. Det medförde att jag blev intresserad av att undersöka hur några av de objektorienterade metoderna fungerar idag.

    Detta arbete tar upp en del av de synpunkter och erfarenheter som några svenska utvecklingsföretag har av de objektorienterade metoderna OMT och Objectory. Syftet med arbetet är bl a att få fram om OMT och Objectory har åtgärdat de brister som de i tidigare litteratur har kritiserats för.

    Den metod som använts för att hantera valt ämne är en kombination av en litteraturstudie och intervjuer/enkäter.

    Det har visat sig under arbetes gång att det är betydligt fler företag som jag har kommit i kontakt med som tillämpar Objectory än OMT. Något överraskande är att alla undersökta företag använder UML-notation och inte OMT och Objectorys ursprungsnotationer. Det anser jag tyda på att UML har fått en stor genomslagskraft. Vidare tyder resultatet av undersökningen på att en del av den kritik som riktats mot OMT och Objectory i litteratur, publicerad i början av 90-talet, har åtgärdats för att förbättra metoderna.

  • 10087.
    Unibaso Eguzkitza, Beñat
    et al.
    University of Skövde, School of Engineering Science.
    Ismail Dobón, Ismael
    University of Skövde, School of Engineering Science.
    Development of a flexible test platform utilizing gearbox simulators through programming2016Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    A gearbox simulator is developed as platform for testing and demonstrating purposes. For that, a rig composed by a mechanical system and electronic equipment for controlling two servomotors is used. The objective of this equipment is to simulate the forces that the gearbox would transmit to the gear lever when the gear change operation is being carried-out. To reach this goal, a program is developed in LabVIEW to command the servomotors, emulating the forces by controlling the output torque and transmitting them to the gear stick as it would be in a real gearbox, taking into account real force-angle curves. Also, a graphical user interface is developed in order to monitor the simulator performance ad ease the way the data is chosen and introduced into the software.As seen in the experiment results, the graphs present similarities in shape and magnitude, which is important in regards of feeling; a better performance could be reach suppressing some system constraints.

  • 10088.
    Urenda Moris, Matias
    et al.
    University of Skövde, School of Technology and Society.
    Eriksson, Patric
    University of Skövde, School of Technology and Society.
    De Vin, Leo
    Introducing discrete event simulation for decision support in the Swedish health care system2004Conference paper (Other academic)
  • 10089.
    Urenda Moris, Matias
    et al.
    University of Skövde, School of Technology and Society.
    Lezama, Thomas
    University of Skövde, School of Technology and Society.
    De Vin, Leo
    University of Skövde, School of Technology and Society.
    Robust design of a Maternity ward supported by discrete event simulation: a case study2007In: Proceedings of the 17th International Conference on Flexible Automation and Intelligent Manufacturing, FAIM 2007, 2007, p. 107-114Conference paper (Refereed)
  • 10090.
    Urenda Moris, Matias
    et al.
    University of Skövde, School of Technology and Society. University of Skövde, The Virtual Systems Research Centre.
    Ng, Amos
    University of Skövde, School of Technology and Society. University of Skövde, The Virtual Systems Research Centre.
    Svensson, Jacob
    University of Skövde, School of Technology and Society. University of Skövde, The Virtual Systems Research Centre.
    Simplification and aggregation strategies applied for factory analysis in conceptual phase using simulation2008In: Proceedings of the 2008 Winter Simulation Conference, IEEE conference proceedings, 2008, p. 1913-1921Conference paper (Refereed)
  • 10091.
    Urenda Moris, Matías
    University of Skövde, The Virtual Systems Research Centre. University of Skövde, School of Technology and Society.
    Dealing with variability in the design, planning and evaluation of Healthcare inpatient units: a modelling methodology for patient dependency variations2010Doctoral thesis, monograph (Other academic)
    Abstract [en]

    This research addresses the fluctuating demand and high variability in healthcare systems. These system’s variations need to be considered whilst at the same time making efficient use of the systems’ resources. Patient dependency fluctuation, which makes determining the level of adequate staffing highly complex, is among the variations addressed. Dealing with variability is found to be a key feature in the design, planning and evaluation of healthcare systems.

    Healthcare providers are facing increasing challenges resulting from an aging population, higher patient expectancies, a shortage of healthcare professionals, as well as increasing costs and reduced funding. Despite the accentuated need for effective healthcare systems and efficient use of resources, many healthcare organisations are inadequately designed and, moreover, poorly managed. Hospital systems consist of complex interrelations between relatively small units, each of which is sensitive to stochastic variations in demand. In addition to this aspect of the system view, a critical resource for the patients’ wellbeing and survival is the staffing level of nurses. This puts the planning and scheduling of human resources as one of the system’s foremost aims. Current tools for staffing and personnel planning in healthcare organisations do not take into consideration the workload variations that result from the variable nature of patient dependency levels.

    The work presents the empirical findings of a number of case studies conducted at a regional hospital in Sweden. Principles and practical suggestions for the robust system design of inpatient wards using Discrete Event Simulation (DES) have been identified. Although DES techniques have, in principle, all the features for modelling the variation and stochastic nature of systems, DES has not been previously used for workload studies of inpatient wards. The main contribution of this work is therefore how a combination of DES and the data of Patient Classification Systems (PCSs) can be used to model workload variations and, subsequently, plan the nurse staffing requirements in systems with high variability. The work presented gives step by step guidance in how the analysis and subsequent modelling of an inpatient ward should be carried out. It defines a novel modelling methodology for patient dependency variations and length of stay modelling of a patient’s dependency progression, including an adaptation to the ward’s discharge figures. The modelling approach opens a novel way of analysing and evaluating the system design of inpatient wards.

  • 10092.
    Urenda Moris, Matías
    et al.
    University of Skövde, School of Technology and Society. University of Skövde, The Virtual Systems Research Centre.
    Ng, Amos H. C.
    University of Skövde, School of Technology and Society. University of Skövde, The Virtual Systems Research Centre.
    Bernedixen, Jacob
    University of Skövde, School of Technology and Society. University of Skövde, The Virtual Systems Research Centre.
    Goienetxea, Ainhoa
    University of Skövde, School of Technology and Society. University of Skövde, The Virtual Systems Research Centre.
    Diseño Y Análisis De Sistemas Productivos Utilizando La Optimización Mediante Simulación Basado En Internet2012In: Ingenieria Industrial, ISSN 0717-9103, E-ISSN 0718-8307, Vol. 11, no 1, p. 37-49Article in journal (Other academic)
  • 10093.
    Urenda Moris, Matías
    et al.
    University of Skövde, School of Technology and Society. University of Skövde, The Virtual Systems Research Centre.
    Ng, Amos H. C.
    University of Skövde, School of Technology and Society. University of Skövde, The Virtual Systems Research Centre.
    Bernedixen, Jacob
    University of Skövde, School of Technology and Society. University of Skövde, The Virtual Systems Research Centre.
    Goienetxea Uriarte, Ainhoa
    University of Skövde, School of Technology and Society. University of Skövde, The Virtual Systems Research Centre.
    Diseño Y Análisis De Sistemas Productivos Utilizando La Optimización Mediante Simulación Basado En Internet2011Conference paper (Refereed)
  • 10094.
    Urkia Kortabarria, Mikel
    University of Skövde, School of Humanities and Informatics. Mondragon Unibertsitatea.
    Web Service Performance on Heterogeneous Systems: A performance comparison between J2EE and .NET on heterogeneous systems2013Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    At the moment, two main web platforms have the monopoly of web service business; NET and J2EE have been competitors in this area for many years. Within last years, a technological advance has occurred with the appearance of Mono, an open source project that allows NET technologies to be taken into operating systems other than Microsoft Windows. This opens an information gap that needs to be solved with a new and actualised performance analysis.

    This thesis work identifies the performance characteristics of the web platforms on heterogeneous systems. The aim of this study is to investigate different performance characteristics of .NET and J2EE web services in heterogeneous systems. The student systems are Windows 7 and Ubuntu Linux.

    A set of web services is built following different service structures, which are then exposed to some quantitative and qualitative test following predefined criteria. The results demonstrate that both .NET and J2EE are suitable web platforms under different circumstances, based mostly on the communication protocol and operating system. This work identifies the best combination of web platform and operating system for each of the web service structures, which can vary for each company.

  • 10095.
    Usynina, Anna A.
    et al.
    Department of Community Medicine, Faculty of Health Sciences, UiT The Arctic University of Norway, Tromsø, Norway / International School of Public Health, Northern State Medical University, Arkhangelsk, Russia.
    Grjibovski, Andrej M.
    International School of Public Health, Northern State Medical University, Arkhangelsk, Russia / Department of Preventive Medicine, International Kazakh-Turkish University, Turkestan, Kazakhstan / Department of International Public Health, Norwegian Institute of Public Health, Oslo, Norway / Department of Public Health, Hygiene and Bioethics, Institute of Medicine, North-Eastern Federal University, Yakutsk, Russia.
    Krettek, Alexandra
    University of Skövde, School of Health and Education. University of Skövde, Health and Education. Department of Community Medicine, Faculty of Health Sciences, UiT The Arctic University of Norway, Tromsø, Norway / Department of Internal Medicine and Clinical Nutrition, Institute of Medicine, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden.
    Odland, Jon Øyvind
    Department of Community Medicine, Faculty of Health Sciences, UiT The Arctic University of Norway, Tromsø, Norway / Department of Public Health, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa.
    Kudryavtsev, Alexander V.
    Department of Community Medicine, Faculty of Health Sciences, UiT The Arctic University of Norway, Tromsø, Norway / International School of Public Health, Northern State Medical University, Arkhangelsk, Russia.
    Anda, Erik Eik
    Department of Community Medicine, Faculty of Health Sciences, UiT The Arctic University of Norway, Tromsø, Norway.
    Risk factors for perinatal mortality in Murmansk County, Russia: a registry-based study2017In: Global Health Action, ISSN 1654-9716, E-ISSN 1654-9880, Vol. 10, no 1, p. 1-10, article id 1270536Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Factors contributing to perinatal mortality (PM) in Northwest Russia remain unclear. This study investigated possible associations between selected maternal and fetal characteristics and PM based on data from the population-based Murmansk County Birth Registry.

    OBJECTIVE: This study investigated possible associations between selected maternal and fetal characteristics and PM based on data from the population-based Murmansk County Birth Registry.

    METHODS: The study population consisted of all live- and stillbirths registered in the Murmansk County Birth Registry during 2006-2011 (n = 52,806). We excluded multiple births, births prior to 22 and after 45 completed weeks of gestation, infants with congenital malformations, and births with missing information regarding gestational age (a total of n = 3,666) and/or the studied characteristics (n = 2,356). Possible associations between maternal socio-demographic and lifestyle characteristics, maternal pre-pregnancy characteristics, pregnancy characteristics, and PM were studied by multivariable logistic regression. Crude and adjusted odds ratios with 95% confidence intervals were calculated.

    RESULTS: Of the 49,140 births eligible for prevalence analysis, 338 were identified as perinatal deaths (6.9 per 1,000 births). After adjustment for other factors, maternal low education level, prior preterm delivery, spontaneous or induced abortions, antepartum hemorrhage, antenatally detected or suspected fetal growth retardation, and alcohol abuse during pregnancy all significantly increased the risk of PM. We observed a higher risk of PM in unmarried women, as well as overweight or obese mothers. Maternal underweight reduced the risk of PM.

    CONCLUSIONS: Our results suggest that both social and medical factors are important correlates of perinatal mortality in Northwest Russia.

  • 10096.
    Usynina, Anna A.
    et al.
    Department of Community Medicine, Faculty of Health Sciences, UiT The Arctic University of Norway, Tromsø, Norway / International School of Public Health, Northern State Medical University, Arkhangelsk, Russia.
    Grjibovski, Andrej M.
    International School of Public Health, Northern State Medical University, Arkhangelsk, Russia / Department of International Public Health, Norwegian Institute of Public Health, Oslo, Norway / Department of Preventive Medicine, International Kazakh-Turkish University, Turkestan, Kazakhstan / Department of Public Health, Hygiene and Bioethics, Institute of Medicine, North-Eastern Federal University, Yakutsk, Russia.
    Odland, Jon Øyvind
    Department of Community Medicine, Faculty of Health Sciences, UiT The Arctic University of Norway, Tromsø, Norway / Department of Public Health, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa.
    Krettek, Alexandra
    University of Skövde, School of Health and Education. University of Skövde, Health and Education. Department of Community Medicine, Faculty of Health Sciences, UiT The Arctic University of Norway, Tromsø, Norway / Department of Internal Medicine and Clinical Nutrition, Institute of Medicine, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden.
    Social correlates of term small for gestational age babies in a Russian Arctic setting2016In: International Journal of Circumpolar Health, ISSN 2242-3982, E-ISSN 2242-3982, Vol. 75, article id 32883Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Small for gestational age (SGA) births have been associated with both short- and long-term adverse health outcomes. Although social risk factors for SGA births have been studied earlier, such data are limited from Northern Russia.

    OBJECTIVE: We assessed maternal social risk factors for term SGA births based on data from the population-based Murmansk County Birth Registry (MCBR).

    DESIGN: Data on term live-born singleton infants born between 2006 and 2011 in Murmansk County were obtained from the MCBR. We applied the 10th percentile for only birth weight (SGAW) or for both birth weight and birth length (SGAWL). Binary logistic regression was used to estimate the effect of independent variables on SGA males and females with adjustment for known risk factors and potential confounders. Both crude and adjusted odds ratios with 95% confidence intervals for the studied risk factors were calculated.

    RESULTS: The proportions of term SGAW and SGAWL births were 9.7 and 4.1%, respectively. After adjustment for potential confounders, the risk of term SGA births among less educated, unemployed, unmarried, smoking and underweight women was higher compared with women from the reference groups. Evidence of alcohol abuse was also associated with birth of SGAWL and SGAW boys. Maternal overweight and obesity decreased the risk of SGA.

    CONCLUSIONS: Maternal low education, unemployment, unmarried status, smoking, evidence of alcohol abuse and underweight increased the risk of term SGA births in a Russian Arctic setting. This emphasizes the importance of both social and lifestyle factors for pregnancy outcomes. Public health efforts to reduce smoking, alcohol consumption and underweight of pregnant women may therefore promote a decrease in the prevalence of SGA births.

  • 10097.
    Usynina, Anna A.
    et al.
    Department of Community Medicine, Faculty of Health Sciences, UiT The Arctic University of Norway, Tromsø, Norway / International School of Public Health, Northern State Medical University, Arkhangelsk, Russia.
    Postoev, Vitaly A.
    Department of Community Medicine, Faculty of Health Sciences, UiT The Arctic University of Norway, Tromsø, Norway / International School of Public Health, Northern State Medical University, Arkhangelsk, Russia.
    Grjibovski, Andrej M.
    International School of Public Health, Northern State Medical University, Arkhangelsk, Russia / Department of International Public Health, Norwegian Institute of Public Health, Oslo, Norway / Department of Preventive Medicine, International Kazakh-Turkish University, Turkestan, Kazakhstan / North-Eastern Federal University, Yakutsk, Russia.
    Krettek, Alexandra
    University of Skövde, School of Health and Education. University of Skövde, Health and Education. Department of Community Medicine, Faculty of Health Sciences, UiT The Arctic University of Norway, Tromsø, Norway / Department of Internal Medicine and Clinical Nutrition, Institute of Medicine, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden.
    Nieboer, Evert
    Department of Community Medicine, Faculty of Health Sciences, UiT The Arctic University of Norway, Tromsø, Norway / Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Canada.
    Odland, Jon Øyvind
    Department of Community Medicine, Faculty of Health Sciences, UiT The Arctic University of Norway, Tromsø, Norway / Department of Public Health, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa.
    Anda, Erik Eik
    Department of Community Medicine, Faculty of Health Sciences, UiT The Arctic University of Norway, Tromsø, Norway.
    Maternal Risk Factors for Preterm Birth in Murmansk County, Russia: A Registry-Based Study2016In: Paediatric and Perinatal Epidemiology, ISSN 0269-5022, E-ISSN 1365-3016, Vol. 30, no 5, p. 462-472Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Globally, about 11% of all liveborn infants are preterm. To date, data on prevalence and risk factors of preterm birth (PTB) in Russia are limited. The aims of this study were to estimate the prevalence of PTB in Murmansk County, Northwestern Russia and to investigate associations between PTB and selected maternal factors using the Murmansk County Birth Registry.

    METHODS: We conducted a registry-based study of 52 806 births (2006-2011). In total, 51 156 births were included in the prevalence analysis, of which 3546 were PTBs. Odds ratios with 95% confidence intervals of moderate-to-late PTB, very PTB and extremely PTB for a range of maternal characteristics were estimated using multinomial logistic regression, adjusting for potential confounders.

    RESULTS: The overall prevalence of PTB in Murmansk County was 6.9%. Unmarried status, prior PTBs, spontaneous and induced abortions were strongly associated with PTB at any gestational age. Maternal low educational level increased the risk of extremely and moderate-to-late PTB. Young (<18 years) or older (≥35 years) mothers, graduates of vocational schools, underweight, overweight/obese mothers, and smokers were at higher risk of moderate-to-late PTB. Secondary education, alcohol abuse, diabetes mellitus, or gestational diabetes were strongly associated with moderate-to-late and very PTB.

    CONCLUSIONS: The observed prevalence of PTB (6.9%) in Murmansk County, Russia was comparable with data on live PTB from European countries. Adverse prior pregnancy outcomes, maternal low educational level, unmarried status, alcohol abuse, and diabetes mellitus or gestational diabetes were the most common risk factors for PTB.

  • 10098.
    Uvnäs Moberg, Kerstin
    University of Skövde, School of Life Sciences.
    Närhetens hormon: oxytocinets roll i relationer2009 (ed. 1)Book (Other academic)
  • 10099.
    Uvnäs-Moberg, Kerstin
    et al.
    University of Agriculture (SLU), Uppsala, Sweden.
    Ekström-Bergström, Anette
    University of Skövde, School of Health and Education. University of Skövde, Health and Education. Department of Health Sciences, University West, Trollhättan, Sweden.
    Berg, Marie
    Institute of Health and Care Sciences, University of Gothenburg, Sweden / Centre for Person-Centred Care, University of Gothenburg, Sweden.
    Buckley, Sarah
    School of Public Health, University of Queensland, Brisbane, Australia.
    Pajalic, Zada
    Faculty of Health Sciences, Oslo and Akershus University, College of Applied Sciences, Oslo, Norway.
    Hadjigeorgiou, Eleni
    Faculty of Health Sciences, Cyprus, University of Technology, Limassol, Cyprus.
    Kotłowska, Alicja
    Faculty of Health Sciences with Subfaculty of Nursing, Institute of Maritime and Tropical Medicine, Medical University of Gdańsk, Gdańsk, Poland.
    Lengler, Luise
    Midwifery Research and Education Unit, Hannover Medical School, Hannover, Germany.
    Kielbratowska, Bogumila
    Faculty of Medical Sciences, Medical University of Gdańsk, Gdańsk, Poland.
    Leon-Larios, Fatima
    Faculty of Nursing, Physiotherapy and Podiatry, University of Seville, Seville, Spain.
    Magistretti, Claudia Meier
    Department of Social Work Center for Health Promotion and Social Participation, Lucerne University of Applied Sciences and Arts, Luzern, Switzerland.
    Downe, Soo
    Research in Childbirth and Health (ReaCH) Group, University of Central Lancashire, Preston, United Kingdom.
    Lindström, Bengt
    Norwegian University of Science and Technology, Trondheim, Norway.
    Dencker, Anna
    Institute of Health and Care Sciences, University of Gothenburg, Sweden / Centre for Person-Centred Care, University of Gothenburg, Sweden.
    Maternal plasma levels of oxytocin during physiological childbirth: A systematic review with implications for uterine contractions and central actions of oxytocin2019In: BMC Pregnancy and Childbirth, ISSN 1471-2393, E-ISSN 1471-2393, Vol. 19, no 1, article id 285Article, review/survey (Refereed)
    Abstract [en]

    Background: Oxytocin is a key hormone in childbirth, and synthetic oxytocin is widely administered to induce or speed labour. Due to lack of synthetized knowledge, we conducted a systematic review of maternal plasma levels of oxytocin during physiological childbirth, and in response to infusions of synthetic oxytocin, if reported in the included studies. Methods: An a priori protocol was designed and a systematic search was conducted in PubMed, CINAHL, and PsycINFO in October 2015. Search hits were screened on title and abstract after duplicates were removed (n = 4039), 69 articles were examined in full-text and 20 papers met inclusion criteria. As the articles differed in design and methodology used for analysis of oxytocin levels, a narrative synthesis was created and the material was categorised according to effects. Results: Basal levels of oxytocin increased 3-4-fold during pregnancy. Pulses of oxytocin occurred with increasing frequency, duration, and amplitude, from late pregnancy through labour, reaching a maximum of 3 pulses/10 min towards the end of labour. There was a maximal 3- to 4-fold rise in oxytocin at birth. Oxytocin pulses also occurred in the third stage of labour associated with placental expulsion. Oxytocin peaks during labour did not correlate in time with individual uterine contractions, suggesting additional mechanisms in the control of contractions. Oxytocin levels were also raised in the cerebrospinal fluid during labour, indicating that oxytocin is released into the brain, as well as into the circulation. Oxytocin released into the brain induces beneficial adaptive effects during birth and postpartum. Oxytocin levels following infusion of synthetic oxytocin up to 10 mU/min were similar to oxytocin levels in physiological labour. Oxytocin levels doubled in response to doubling of the rate of infusion of synthetic oxytocin. Conclusions: Plasma oxytocin levels increase gradually during pregnancy, and during the first and second stages of labour, with increasing size and frequency of pulses of oxytocin. A large pulse of oxytocin occurs with birth. Oxytocin in the circulation stimulates uterine contractions and oxytocin released within the brain influences maternal physiology and behaviour during birth. Oxytocin given as an infusion does not cross into the mother's brain because of the blood brain barrier and does not influence brain function in the same way as oxytocin during normal labour does. 

  • 10100.
    Uvnäs-Moberg, Kerstin
    et al.
    Department of Animal Environment and Health, Swedish University of Agricultural Sciences, Skara, Sweden.
    Handlin, Linda
    University of Skövde, School of Health and Education. University of Skövde, Health and Education.
    Kendall-Tackett, Kathleen
    Texas Tech University School of Medicine, Amarillo, TX, USA.
    Petersson, Maria
    Department of Molecular Medicine and Surgery, Endocrine and Diabetes Unit, Karolinska Institutet, Sweden.
    Oxytocin is a principal hormone that exerts part of its effects by active fragments2019In: Medical Hypotheses, ISSN 0306-9877, E-ISSN 1532-2777, Vol. 133, p. 1-9, article id 109394Article in journal (Refereed)
    Abstract [en]

    Oxytocin is a nonapeptide consisting of a cyclic six amino-acid structure and a tail of three amino acids. It was originally known for its ability to induce milk ejection and to stimulate uterine contractions. More recently, oxytocin has been shown to stimulate social behaviors, and exert pain-relieving, anti-stress/anti-inflammatory and restorative effects. We hypothesize that oxytocin is a principal hormone that, in part, exerts its effects after degradation to active fragments with more specific effect profiles. Experimental findings on rats show that administered oxytocin exerts biphasic effects. For example, after an initial increase in pain threshold, a second more long-lasting increase follows. Blood pressure and cortisol levels initially increase and then reverse into a long-lasting decrease in blood pressure and cortisol. Whereas the initial effects are, the second-phase effects are not blocked by an oxytocin antagonist, but by an opioid mu-antagonist and by an alpha 2-adrenoreceptor antagonist, respectively, suggesting that other receptors are involved. Repeated administration of oxytocin induces multiple anti-stress effects, which are mediated by alpha 2-adrenoreceptors. Repeated administration of linear oxytocin and linear oxytocin fragments with a retained C-terminal reduce spontaneous motor activity, a sedative or anti-stress effect, suggesting that alpha 2-adrenoreceptors have been activated. In contrast, linear mid-fragments stimulate motor activity. Low-intensity stimulation of cutaneous nerves in rats, as well as breastfeeding and skin-to-skin contact between mothers and babies, trigger immediate anti-stress effects. Some of these effects are likely caused by open ring/linear C-terminal fragments activating alpha 2-adrenoreceptors. Oxytocin fragments may be pre-formed and released in the brain or created by metabolic conversion of the principal hormone oxytocin in the central nervous system. Oxytocin and its fragments may also be released from peripheral sites, such as peripheral nerves, the gastrointestinal tract, and blood vessels in response to decreased sympathetic or increased parasympathetic nervous tone. Smaller fragments of oxytocin produced in the periphery may easily pass the blood-brain barrier to induce effects in the brain. In conclusion, oxytocin is linked to many different, sometimes opposite effects. The intact cyclic molecule may act to initiate social interaction and associated psychophysiological effects, whereas linear oxytocin and C-terminal fragments may induce relaxation and anti-stress effects following social interaction. In this way, the principal hormone oxytocin and its fragments may take part in a behavioral sequence, ranging from approach and interaction to calm and relaxation. Linear fragments, with an exposed cysteine-residue, may exert anti-inflammatory and antioxidant effects and thereby contribute to the health-promoting effects of oxytocin. 

199200201202203204205 10051 - 10100 of 10835
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • 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