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  • Näsman, Caroline
    et al.
    Umeå University, Faculty of Social Sciences, Department of Education.
    Näsman, Caroline
    Umeå University, Faculty of Social Sciences, Department of Education.
    Hyvönen, Charlotta
    Umeå University, Faculty of Social Sciences, Department of Education.
    Gender and Leadership in Brazil – a Study on Women in Management Positions2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The aim of this study was to examine women in management positions in the Brazilian labor market, focusing on perception of their working condition but also challenges in a culture dominated by machismo and stereotypes. The data was conducted from a qualitative approach with a mix of snowball and convenience sample, by interviewing eight women with staff responsibilities in a wide range of sectors and branches. The result section revealed that the Brazilian society is characterized by a conservative approach and machismo, which create barriers for women to enter higher positions such as management.The combination of women being associated with household, caregiving and motherhood together with being submissive to men, reduces the chances to establish themselves in the labor market. However, the majority of the female leaders stated differences between male and female leadership, based on traditional ways of being leaders due to stereotypes.Although there are several aspects that create obstacles for women, there was one that stood out from the others, the sector they were employers in. Half of the participants worked in the private sector and the remaining half in the public one. Wishing for a life with family and improved working conditions could be achieved in the public sector and was highly unlikely in the private sector. These obstacles that women have to face and overcome make it hard to balance a career with a personal life.

  • Fredman, Sara
    et al.
    Umeå University, Faculty of Social Sciences, Department of Education.
    Fredman, Sara
    Umeå University, Faculty of Social Sciences, Department of Education.
    Näsman, Albin
    Umeå University, Faculty of Social Sciences, Department of Education.
    Employer branding inom offentlig verksamhet: En fallstudie om Vännäs kommun som attraktiv arbetsgivare2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Det råder olika villkor i den privata och offentliga sektorn gällande geografisk bundenhet, konkurrans och förutsättningar för att styra verksamheterna. Det som däremot är gemensamt för de båda sektorerna är konkurrensen om medarbetare. Vännäs kommun befinner sig i en inledande fas i arbetet med begreppet attraktiv arbetsgivare, även kallat Employer Branding. Uppdraget har varit att undersöka vilka positiva aspekter som upplevs med att arbeta för Vännäs kommun, som medarbetare med varierande anställningstid och ålder upplever samt hur kommunen kan stärka sitt arbetsgivarvarumärke genom att betona dessa aspekter. I resultatet framkom att positiva aspekter med Vännäs kommun som arbetsgivare är närhet, framåtanda, utveckling och ansvar, gemenskap och välmående samt organisationen i sin helhet. Från dessa kategorier har följande tema utarbetats; I Vännäs kommun råder en kontinuerlig strävan efter utveckling både för organisationen och medarbetarna. Organisationskulturen är välkomnande där gemenskap och välmående står i fokus. Den lilla kommunens fördel är det övergripande koncerntänket med närhet till beslut och möjlighet till påverkan. Detta illustrerar vad som kännetecknar Vännäs kommun som arbetsgivare. För att specifikt attrahera yngre arbetskraft visar resultatet att följande faktorer är viktiga för yngre medarbetare i organisationen; innovation, känna sig behövd och värdefull, en bra arbetsmiljö och arbetskultur, gemenskap på arbetsplatsen och att bli betrodd med ansvar. Det som mest frekvent uttrycktes från den yngre informantgruppen var vikten av utveckling genom arbetet. Denna fallstudie kan vara användbar för organisationer med liknande förutsättningar som Vännäs kommun i arbetet med employer branding. Fallstudien bidrar även med en ökad förståelse för vad som attrahetar medarbetare till en offentlig organisation.

  • Yan, Yutong
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Yan, Yutong
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Simulation, Control and Path Planning for Articulated Unmanned Ground Vehicles2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The purpose of this project is to implement obstacle avoidance algorithms to drive the articulated vehicle autonomously in an unknown environment, which is simulated by AgX Dynamics™ simulation software and controlled by Matlab® programming software. Three driving modes are developed for driving the vehicle (Manual, Semi-autonomous and Autonomous) in this project. Path tracking algorithms and obstacle avoidance algorithms are implemented to navigate the vehicle. A GUI was built and used for the manual driving mode in this project. The semi-autonomous mode checked different cases: change lanes, U-turn, following a line, following a path and figure 8 course. The autonomous mode is implemented to drive the articulated vehicle in an unknown environment with moving to a pose path tracking algorithm and VFH+ obstacle avoidance algorithm. Thus, the simulation model and VFH+ obstacle avoidance algorithm seems to be working fine and still can be improved for the autonomous vehicle. The result of this project showed a good performance of the simulation model. Moreover, this simulation software helps to minimize the cost of the articulated vehicle since all tests are in the simulation rather than in the reality.

  • Public defence: 2016-12-16 09:00 Hörsal F, Humanisthuset, Umeå
    Bohm, Ingela
    Umeå University, Faculty of Social Sciences, Department of Food and Nutrition.
    Bohm, Ingela
    Umeå University, Faculty of Social Sciences, Department of Food and Nutrition.
    “We’re made of meat, so why should we eat vegetables?”: food discourses in the school subject home and consumer studies2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Background

    Food has many different functions. On a physical level, it is needed to survive and to maintain health, but it also has many social, psychological, and emotional meanings. For example, food is used to build relationships, to mark hierarchies, to celebrate holidays, and to influence mood and self-image. Different foods have different cultural meanings, and people are socialized from an early age to recognize and utilize their symbolic value.

    One arena where food occupies a central position is the Swedish school subject Home and Consumer Studies (HCS), which focuses on both the physical and the psychosocial dimensions of food-related health. Since these dimensions are not always compatible, the aim of this dissertation was to explore how students and teachers of HCS use big ‘D’ Discourses to talk about and handle food, with a special focus on vegetables, meat, vegetarian food, and sweet foods.

    Methods

    Fifty-nine students and five teachers were observed, recorded, and in some cases video-taped. Participants’ talk about vegetables, meat, vegetarian food, and sweet foods was transcribed verbatim and analysed for big ‘D’ Discourses.

    Results

    Students mostly based their choice of vegetables on sensory and cultural Discourses. Some vegetables were mandatory and others were optional, depending on whether or not they were part of a recipe or a cultural tradition. The health Discourse was only used if a specific assignment demanded it, and was closely tied to the evaluation Discourse.

    Contrary to the sometimes optional status of vegetables, meat was seen as central in the sensory, cultural, health, and social Discourses. Therefore the reduction of meat could be problematic. It was regarded as simultaneously healthy and unhealthy, and it could elicit disgust, but whenever participants talked about decreasing meat consumption, its centrality was invoked as a counterargument.

    As an extension of this, vegetarian food was seen as ‘empty’, deviant, and an unattainable ideal. Access to vegetarian food was limited for meat-eaters, and vegetarians were othered in both positive and negative ways. When vegetarian food was cooked during lessons, it was constructed as something out of the ordinary.

    Sweet foods could be viewed as a treasure, as something dangerous and disgusting, or as an unnecessary extra. Home-made varieties were seen as superior. Sweet foods gave social status to both students and teachers, and they could be traded or given away to mark relationships and hierarchies, but also withheld and used to police others.

    Conclusion

    In summary, two powerful potential opposites met in the HCS classroom: the Discourses of normality (sensory, cultural, and social Discourses), and the Discourses of responsibility (health and evaluation). Normality could make physically healthy food choices difficult because of participants’ social identity, the conflicted health Discourse, and too-strict ideals. On the other hand, some people were excluded from normality itself, notably vegetarians, who were seen as deviant eaters, and teachers, who had to balance state-regulated goals in HCS against local norms.

    To counteract such problems, teachers can 1) focus on sensory experiences, experimental cooking methods, and already popular foods, 2) challenge normality by the way they speak about and handle different types of food, 3) make cooking and eating more communal and socially inclusive, 4) explore the psychosocial dimension of health on the same level as the physical dimension, and 5) make sure they do not grade students’ cultural backgrounds, social identities, or taste preferences. This might go some way towards empowering students to make informed choices about food and health. However, scant resources of things like time, money, and equipment limit what can be achieved in the subject.

  • högberg, emma
    Umeå University, Faculty of Social Sciences, Umeå University School of Restaurant and Culinary Arts.
    högberg, emma
    Umeå University, Faculty of Social Sciences, Umeå University School of Restaurant and Culinary Arts.
    Hur formar gästen sin lunchtallrik om den får möjlighet att välja mellan en fiskrätt, en kötträtt och en vegetarisk rätt? Vilka drivkrafter påverkar deras val?2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • Hoppman, Emma
    et al.
    Umeå University, Faculty of Social Sciences, Department of Education.
    Hoppman, Emma
    Umeå University, Faculty of Social Sciences, Department of Education.
    Åberg, Therese
    Umeå University, Faculty of Social Sciences, Department of Education.
    Tag vara på tiden och vinn striden!: En studie kring hur företag kan använda arbetstidsförkortning i sitt employer branding-arbete2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    På en arbetsmarknad där konkurrensen hårdnat kring arbetet med att attrahera och behålla personal och där företag idag måste vara kreativa i arbetet med att profilera sig såg vi det av intresse att undersöka fenomenet arbetstidsförkortning. Detta med syfte att skapa en djupare förståelse kring hur företag och organisationer kan använda reducerad arbetstid som ett led i sitt employer branding-arbete. Studien syftade till att besvara bakgrunden till införandet av arbetstidsförkortning, hur arbetstidsmodellen var utformad, hur arbetstidsförkortning användes i arbetet med employer branding samt till hur företag och organisationer kan arbeta strategiskt med detta i syfte att attrahera och behålla personal. I studien ingick åtta företag/organisationer inom olika branscher med stor variation i antal anställda. Materialet samlades in genom semistrukturerade intervjuer. Resultatet visade på skillnader vad gäller bakgrunden till införandet av arbetstidsförkortning samt hur och i vilken utsträckning det används i employer branding-arbetet. Bland respondenterna lyftes övervägande positiva effekter fram där många beskrev hur de genom satsningen idag har lyckats effektivisera arbetet och där medarbetarna ges mer tid till sitt privata liv. En ytterligare effekt satsningen medfört är ett ökat intresse för dem som företag både från medarbetare samt kunder. Studien visar på att arbetstidsförkortning kan användas framgångsrikt i företag och organisationers employer branding arbete men arbetet med detta bör implementeras på en strategisk nivå för att skapa förutsättningar för långsiktiga resultat.

  • Lindmark, Cecilia
    et al.
    Umeå University, Faculty of Science and Technology, Department of Computing Science.
    Lindmark, Cecilia
    Umeå University, Faculty of Science and Technology, Department of Computing Science.
    Nilsson, Jonas
    Umeå University, Faculty of Science and Technology, Department of Computing Science.
    Modeling user preferences and norms in context-aware systems2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The aim of this thesis has been to theoretically investigate how a context- aware system for mobile applications should behave when a phone call is received while driving in a general setting, while the system considers user preferences and norms. By norm, we mean a sort of rule that a user has to follow in a given environment, e.q. traffic. The investigation has lead to an approach on how a general setting could be implemented; in particular, by general setting we mean that the user is a car driver and the environment is the public roads. A given system (e.q. an app) supports the interaction between the user and the environment. A use case has been used as a basis for the investigation, that involves forwarding calls while considering user preferences and norms while driving in front of a school.

    The first steps, in this thesis, have been to model the user profile and the environment profile, and to find activation and deactivation conditions of both user preferences and norms. An algorithm in pseudocode has been provided that manages how a context-aware system will handle the context-aware decision making process. The decision making process has then been evaluated, and the evaluation has been done while considering real mobile applications on the market.

    The results of this thesis can be used, for example, as a basis for implementing context-aware mobile applications, e.q. applications handling calls.

  • Thelin, Robert
    Umeå University, Faculty of Science and Technology, Department of Computing Science.
    Thelin, Robert
    Umeå University, Faculty of Science and Technology, Department of Computing Science.
    Interactive Video in Online Education: Evaluation of Current Video Delivery Systems for Interactive Features Defined in Literature2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Increasingly lectures are being offered online in the form of online lecture videos. Although more and more lectures are now being offered online in the form of videos, they tend to be mostly non-interactive and linear. This thesis examines current approaches to online learning and evaluate current video delivery services to determine if they can support the kind of interactive features that are defined in the literature. The thesis shows that the video delivery services can be used to integrate interactive elements, but will do so by being used together with other technologies, such as HTML5.

  • Ramos, Alexander
    Umeå University, Faculty of Science and Technology, Department of Computing Science.
    Ramos, Alexander
    Umeå University, Faculty of Science and Technology, Department of Computing Science.
    Evaluating the ability of static code analysis tools to detect injection vulnerabilities2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Identifying and eliminating security vulnerabilities in programs can be very time consuming. A way to automate and speed up the process is to integrate static code analysis tools in the development process. Choosing a static code analysis tool for a project is not an easy task since different tools have their own strengths and performance characteristics. One way of testing the qualifications of a tool for finding flaws is to test them against a test suite, constructed for the specific purpose of static code analysis tool testing. In this paper the tools Visual Code Grepper, FindBugs and SonarQube are tested for their ability to detect SQL, OS command and LDAP injection vulnerabilities against the Juliet test suite v1.2 for Java and the performance of the tools are evaluated. Since the tools have their own techniques for finding errors and vulnerabilities, diverse results are obtained where the tools show their strengths and weaknesses which are presented in tables and graphs. In general, the FindBugs tool seems to be the most suitable tool for detecting potential injections, however further studies including more test cases should be conducted to cover more of what the tools are capable of detecting. To cover most of the vulnerabilities in a program, it would be ideal to use as many tools as possible to locate the maximum amount of flaws

  • Abedin, Reaz Ashraful
    Umeå University, Faculty of Science and Technology, Department of Computing Science.
    Abedin, Reaz Ashraful
    Umeå University, Faculty of Science and Technology, Department of Computing Science.
    Autonomous Object Category Learning for Service Robots Using Internet Resources2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    With the developments in the field of Artificial Intelligence (AI), robots are becoming smarter, more efficient and capable of doing more dififcult tasks than before. Recent progress in Machine Learning has revolutionized the field of AI. Rather than performing pre-programmed tasks, nowadays robots are learning things, and becoming more autonomous along the way. However, in most of the cases, robots need a certain level of human assistance to learn something. To recognize or classify daily objects is a very important skill that a service robot should possess. In this research work, we have implemented a fully autonomous object category learning system for service robots, where the robot uses internet resources to learn object categories. It gets the name of an unknown object by performing reverse image search in the internet search engines, and applying a verification strategy afterwards. Then the robot retrieves a number of images of that object from internet and use those to generate training data for learning classifiers. The implemented system is tested in actual domestic environment. The classification performance is examined against some object categories from a benchmark dataset. The system performed decently with 78:40% average accuracy on ve object categories taken from the benchmark dataset and showed promising results in real domestic scenarios. There are existing research works that deal with object category learning for robots using internet images. But those works use Human-in-the-loop models, where humans assist the robot to get the object name for using it as a search cue to retrieve training images from internet. Our implemented system eliminates the necessity of human assistance by making the task of object name determination automatic. This facilitates the whole process of learning object categories with full autonomy, which is the main contribution of this research.

  • Söderqvist, Frida
    et al.
    Umeå University, Faculty of Medicine, Department of Odontology.
    Söderqvist, Frida
    Umeå University, Faculty of Medicine, Department of Odontology.
    Willdén, Nina
    Umeå University, Faculty of Medicine, Department of Odontology.
    Quantitative Analysis of Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis in Adolescents from Ghana2016Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Periodontitis is an inflammatory disease associated with different bacterial species, including P. gingivalis and A. actinomycetemcomintans. This study is based on a previous study where bacterial samples were collected from periodontal pockets on adolescents in Ghana. The objective was to quantitatively analyse the samples concerning A. actinomycetemcomitans and P. gingivalis and to correlate them towards each other. Furthermore, A. actinomycetemcomitans was correlated against development of attachment loss. Out of 315 available samples from periodontally healthy adolescents, 162 were successfully analysed using qPCR. Excel and SPSS were used for statistical calculations and analyses. Medium levels (1 – 10 %) of A. actinomycetemcomitans indicated a significant higher risk (p = 0.005) for development of attachment loss compared to low levels (< 1 %). Also, a significant risk (p = 0.024) for development of attachment loss was found for levels over 1 % compared to levels lower than 1 % (including negative samples). Surprisingly, no significant higher risk was found when comparing A. actinomycetemcomitans negative samples with low, medium and high (> 10 %) bacterial proportions. No significant correlation (p = 0.144) was found between proportions of A. actinomycetemcomitans and P. gingivalis in the same sample. The concluding remarks are that A. actinomycetemcomitans detected in levels exceeding 1 %, particularly 1 – 10 %, are most associated with development of attachment loss. There is no significant negative correlation between high levels of A. actinomycetemcomitans and P. gingivalis in periodontal pockets before attachment loss can be detected.

  • Palmebjörk, Isabel
    Umeå University, Faculty of Social Sciences, Department of Education.
    Palmebjörk, Isabel
    Umeå University, Faculty of Social Sciences, Department of Education.
    Att hitta Den rätta: En kvalitativ studie om rekryteringsprocessen2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Uppsatsens syfte har varit att undersöka och få en förståelse för på vilka sätt konsultchefer från olika bemanningsföretag säkerställer kundernas krav på kompetens och egenskaper i sina rekryteringsprocesser. Vidare har också undersökts vad de anser om tillförlitligheten i de urvalsmetoder de använder. För att uppnå studiens syfte genomfördes semistrukturerade intervjuer med sex konsultchefer verksamma på olika bemanningsföretag. Resultatet visade att samtliga respondenter utgår från kravspecifikationen i rekryteringsprocessen, enligt modellen för kompetensbaserad rekrytering. Vidare visar resultatet att kunderna inte alltid lägger ner önskvärd tid på att utforma kravspecifikationen. Sammantaget med det faktum att de inte alltid själva definierar kompetensbegreppen för den kandidat de eftersöker, riskerar att minska rekryteringens träffsäkerhet då konsultchefens subjektiva tolkning av ett begrepp inte nödvändigtvis går i linje med kundens. Oavsett medvetenhet om forskningsresultat gällande olika HR praktikers validitet, använder konsultcheferna urvalsmetoder med hög validitet. Således visar resultatet att den diskrepans som enligt många forskare finns mellan forskning och praktik snarare beror på fundamentalt olika referensramar än att använda sig av urvalsmetoder med låg validitet.

  • Jonsson, Julia
    Umeå University, Faculty of Social Sciences, Department of applied educational science.
    Jonsson, Julia
    Umeå University, Faculty of Social Sciences, Department of applied educational science.
    Blivande studie- och yrkesvägledares syn på karriärportföljen: En kvalitativ studie av karriärportföljen som kompetensutvecklande verktyg2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Studien undersöker vad fyra studenter på studie- och yrkesvägledarprogrammet anser karriärportföljen tillför gällande kompetensutveckling, lärande och självinsikt. Syftet med studien är att undersöka erfarenheter av att använda karriärportföljen som verktyg och hur studenterna anser att de kompetensutvecklats. Arbetet belyser hur studenterna resonerar kring karriärportföljen. Starka sidor är det överblickande perspektivet av studierna och hur det påverkar kompetensutveckling, lärandeprocessen och självinsikten. Det belyser även påverkansfaktorer som medför att studenterna inte använder karriärportföljen under alla kurser. Resultatet av undersökningen visar dels att studenterna saknar formell återkoppling och att de anser att det blir betungande att arbeta extra med karriärportföljen utöver kursens vanliga arbeten. Dessutom visar resultaten behov av att revidera syftet samt strukturen och ramarna för karriärportföljen. På så vis skapas en tydlig målbild som motiverar studenterna att använda portfolion. 

  • Höber, Jenny
    et al.
    Umeå University, Faculty of Social Sciences, Umeå School of Business and Economics (USBE), Business Administration.
    Höber, Jenny
    Umeå University, Faculty of Social Sciences, Umeå School of Business and Economics (USBE), Business Administration.
    Karlsson, Johanna
    Umeå University, Faculty of Social Sciences, Umeå School of Business and Economics (USBE), Business Administration.
    Förbättring av tjänstekvalitén på särskilda boenden i Umeå kommun: En kvantitativ studie om hur tjänstekvalitén kan förbättras ur kundens och tjänsteleverantörens perspektiv2016Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    SAMMANFATTNINGÄldreomsorgen och kvalitén på denna har varit ett debatterat ämne under många år, och förhållandena på särskilda boenden har under de senaste åren varit föremål för en extra hård granskning till följd av bland annat vanvård, långa kötideroch liten möjlighet att erbjuda vård utöver det absolut nödvändigaste. I Socialstyrelsens rikstäckande undersökning, som mäter de boendes nöjdhet avseende sin vård och omsorg, har Umeå därtill presterat sämre än rikssnittet avseende 18 av 20 kvalitetsindikatorer. Mot bakgrund av detta fokuserar denna studie på tjänstekvalitén på särskilda boenden inom Umeå kommun, med syftet att hitta förbättringsåtgärder.Äldreomsorgen är en organisation som tillhandahåller tjänster vilket innebär att det inte endastär de externa kunderna som är viktiga –inom tjänstesektorn spelar även de interna kunderna en avgörande roll. De externa kunderna är i detta sammanhang de boende och de interna kunderna utgörs av den personal som arbetar på dessa särskilda boenden, det vill säga vårdbiträden och undersköterskor. Dessa interna kunder befinner sig i direkt anslutning till de externa kunderna och påverkar därför levererandet av tjänsten i allra högsta grad, varför det således är viktigt att dessa får den hjälp och det stöd som de behöver.Eftersom vi ser ett så tydligt samband mellan personalen och den levererade kvalitén blev därmed personalens psykosociala arbetsmiljö det som blev fokus för studiens förbättringsåtgärder. Vi hade under vår litteratursökning inte funnit någon studie som specifikt sammankopplat kända faktorer inom den psykosociala arbetsmiljön, med de kvalitetsindikatorer som kan sägas utgöra tjänstekvalité inom äldreomsorgen. Studien genomfördes på fyra särskilda boenden inom Umeå kommun och består i två delar. Den första delen bestod i att mätatjänstekvalitén genom strukturerade intervjuer med de boende. Nästa del var att genom en enkätundersökning bland personalen sammankopplatjänstekvaliténmed den psykosociala arbetsmiljön. Slutligen har vi sammanställt förbättringsåtgärdergenom att kombinera en teoretisk grund med konkreta förslag från såväl boende som personal. Vid analysen av det empiriska materialet visade det sig att personalen ansåg att samtliga arbetsmiljöfaktorer var viktiga för samtliga kvalitetsindikatorer, vilket alltså tydliggör ett starkt subjektivt samband mellan den psykosociala arbetsmiljön och tjänstekvalitén inom äldreomsorgen. Detta kan sägas vara studiens viktigaste slutsats. Gällande nyanser i om någon arbetsmiljöfaktor var viktigare än en annan så framkom även detta. Det framgick bland annat att arbetsbelastningen ständigt graderades som viktigast för tjänstekvaliténs utförande, något som i de flesta fall också gällde för ett positivt socialt klimatsamt möjligheten att påverka arbetstakt. Mot bakgrund av det innehåller förbättringsåtgärderna bland annat att anpassa personalstyrkan utifrån antalet boende per avdelning, genomföra teambuilding-aktiviteter samt erbjuda personal ökaddelaktighet i schemaläggning.Sammanfattande kan sägas att mät-delen av studien visade sig vara mycket komplex. Den största utmaningen var att även de sjukaste ska få komma till tals, något som vi dessvärre inte lyckades med i vår studie. Personalens tidsbrist och i vissa fall svaga tilltro till att deras förslag tas på allvar, gjorde också att vi hade svårigheter att få tillräckligt antal svar. Att kunna generalisera studiens resultat i viss mån blev, den kvantitativa ansatsen till trots, inte möjlig. Ytterligare forskning krävs för att i större skala kunna befästa samband mellan tjänstekvalité och arbetsmiljö, och även för att finna tillvägagångssätt däräldre och sjuka personer kan få komma till tals om hur de upplever kvalitén på den vård som erbjuds.

  • Warnet, Charles
    et al.
    Umeå University, Faculty of Social Sciences, Umeå School of Business and Economics (USBE), Business Administration.
    Warnet, Charles
    Umeå University, Faculty of Social Sciences, Umeå School of Business and Economics (USBE), Business Administration.
    Laurain, Nicolas
    Umeå University, Faculty of Social Sciences, Umeå School of Business and Economics (USBE), Business Administration.
    Influence of the community on consumption behaviours2016Independent thesis Advanced level (degree of Master (Two Years)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Communities and their specific consumptions is a fundamental subject to understand our world which is, most of the time, different from what we already know. In a period of globalization and of profound changes in human relations, it is important to understand other cultures, other spiritualities and other conceptions of life. Marc Aurelius said “We are the other of the other”, which means that our conception of the world is not the right answer, but one of the possible answers.

    This research studies the relation between the consumption and community. The purpose of this thesis is to identify the key elements that influence the consumption of an individual within a community, the impact of the community members on the community consumption behaviour, and how industries and professionals could answer to the community needs in terms of products and services. In addition, we have made a focus on the influence of a specific member of a community: the leader.

    To be more precise, the research fulfils different objectives which are: first, to review and identify key principles of communities, from existing literature; second, to adopt a 360° study method which allows us to have an overview of our problem by collecting data from different actors of the subject (Opinion leaders, professionals and customers);

    The literature review and this qualitative data collection helped us to identify the key elements which lead and determine the relation between consumption and communities.

    With this purpose in mind, we were motivated to collect qualitative primary data through an interpretivism paradigm. We conducted semi-structured interviews with open questions with selected participants who have a key role in the community. The main objective of the interviews was to gain a comprehensive and reliable perception of the situation from different key points of view.

    Our main goal is to identify what are the key elements in the relation between communities and consumption. On this road, we also wanted to know why a community is tightening on its practices and if their consumption may attract non-members of the community.

  • Norman, Jenna
    Umeå University, Faculty of Social Sciences, Department of Political Science.
    Norman, Jenna
    Umeå University, Faculty of Social Sciences, Department of Political Science.
    Resiliens: En studie om diskrepansen mellan begreppet resiliens och den empiriska tillämpningen2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The purpose of this qualitative study is through survey investigate if there is a discrepancy between the theoretical concept of resilience and the empirical application. To answer this question this study examines the following issues: What is included in various theoretical resilience concept? What is the meaning of the resilience concept at the Swedish crisis management actors today? How does the Swedish crisis management actors use resilience to make cities safer in the future? This study will be helpful for crisis management actors in their understanding of what the resilience concept and find the knowledge of these three concepts to use it in their practical work when they talk about working for resilience. In this study, twenty-six questionnaires was sent out to people who in some way are involved in crisis management. The respondents in this study work at different levels (municipal, county government, government, private sector and researchers). Research and theories of resilience is based on Brian Walker and David Salt describing engineering technical resilience and ecological resilience in the book Resilience thinking then Ulrich Beck explains according to the book Risk Society how one must work for the future and not look backwards and plan because of what was happening in the past. Pickett, McGrath, Cadenasso & Felson describes his research Ecological Resilience and Resilient Cities how sustainability is an important aspect of resilience. Finally the third concept is described, namely socio-ecological resilience where Carl Folke lifts the importance of developing resilience for the socio-ecological system to create an adaptability that allows for continuous development, a dynamic adaptive interaction between maintaining and developing in change. In order to reduce the discrepancy between the concept of resilience and the empirical application it requires, first and foremost an understanding and a knowledge of the concept of resilience. Then it requires a collaboration between various stakeholders especially the crisis management actors to take part of the research evidence and have a will to implement it practically and as a result get new innovative ideas to work with.

  • Carr, Joel A.
    et al.
    Carr, Joel A.
    D'Odorico, Paolo
    Suweis, Samir
    Seekell, David A.
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    What commodities and countries impact inequality in the global food system?2016In: Environmental Research Letters, ISSN 1748-9326, E-ISSN 1748-9326, Vol. 11, no 9, 095013Article in journal (Refereed)
    Abstract [en]

    The global distribution of food production is unequal relative to the distribution of human populations. International trade can increase or decrease inequality in food availability, but little is known about how specific countries and commodities contribute to this redistribution. We present a method based on the Gini coefficient for evaluating the contributions of country and commodity specific trade to inequality in the global food system. We applied the method to global food production and trade data for the years 1986-2011 to identify the specific countries and commodities that contribute to increasing and decreasing inequality in global food availability relative to food production. Overall, international trade reduced inequality in food availability by 25%-33% relative to the distribution of food production, depending on the year. Across all years, about 58% of the total trade links acted to reduce inequality with similar to 4% of the links providing 95% of the reduction in inequality. Exports from United States of America, Malaysia, Argentina, and Canada are particularly important in decreasing inequality. Specific commodities that reduce inequality when traded include cereals and vegetables. Some trade connections contribute to increasing inequality, but this effect is mostly concentrated within a small number of commodities including fruits, stimulants, and nuts. In terms of specific countries, exports from Slovenia, Oman, Singapore, and Germany act to increase overall inequality. Collectively, our analysis and results represent an opportunity for building an enhanced understanding of global-scale patterns in food availability.

  • Marchand, Philippe
    et al.
    Marchand, Philippe
    Carr, Joel A.
    Dell'Angelo, Jampel
    Fader, Marianela
    Gephart, Jessica A.
    Kummu, Matti
    Magliocca, Nicholas R.
    Porkka, Miina
    Puma, Michael J.
    Ratajczak, Zak
    Rulli, Maria Cristina
    Seekell, David A.
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Suweis, Samir
    Tavoni, Alessandro
    D'Odorico, Paolo
    Reserves and trade jointly determine exposure to food supply shocks2016In: Environmental Research Letters, ISSN 1748-9326, E-ISSN 1748-9326, Vol. 11, no 9, 095009Article in journal (Refereed)
    Abstract [en]

    While a growing proportion of global food consumption is obtained through international trade, there is an ongoing debate on whether this increased reliance on trade benefits or hinders food security, and specifically, the ability of global food systems to absorb shocks due to local or regional losses of production. This paper introduces a model that simulates the short-term response to a food supply shock originating in a single country, which is partly absorbed through decreases in domestic reserves and consumption, and partly transmitted through the adjustment of trade flows. By applying the model to publicly-available data for the cereals commodity group over a 17 year period, we find that differential outcomes of supply shocks simulated through this time period are driven not only by the intensification of trade, but as importantly by changes in the distribution of reserves. Our analysis also identifies countries where trade dependency may accentuate the risk of food shortages from foreign production shocks; such risk could be reduced by increasing domestic reserves or importing food from a diversity of suppliers that possess their own reserves. This simulation-based model provides a framework to study the short-term, nonlinear and out-of-equilibrium response of trade networks to supply shocks, and could be applied to specific scenarios of environmental or economic perturbations.

  • Zhao, Gang
    et al.
    Zhao, Gang
    Tan, Wei
    Jia, Mengyuan
    Hou, Jiajuan
    Ma, Weiguang
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Dong, Lei
    Zhang, Lei
    Feng, Xiaoxia
    Wu, Xuechun
    Yin, Wangbao
    Xiao, Liantuan
    Axner, Ove
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Jia, Suotang
    Intensity-Stabilized Fast-Scanned Direct Absorption Spectroscopy Instrumentation Based on a Distributed Feedback Laser with Detection Sensitivity down to 4 x 10(-6)2016In: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 16, no 9, 1544Article in journal (Refereed)
    Abstract [en]

    A novel, intensity-stabilized, fast-scanned, direct absorption spectroscopy (IS-FS-DAS) instrumentation, based on a distributed feedback (DFB) diode laser, is developed. A fiber-coupled polarization rotator and a fiber-coupled polarizer are used to stabilize the intensity of the laser, which significantly reduces its relative intensity noise (RIN). The influence of white noise is reduced by fast scanning over the spectral feature (at 1 kHz), followed by averaging. By combining these two noise-reducing techniques, it is demonstrated that direct absorption spectroscopy (DAS) can be swiftly performed down to a limit of detection (LOD) (1 sigma) of 4 x 10(-6), which opens up a number of new applications.

  • Samuelsson, Erik
    Umeå University, Faculty of Science and Technology, Department of Computing Science.
    Samuelsson, Erik
    Umeå University, Faculty of Science and Technology, Department of Computing Science.
    Location independent inter-process communication as software buses2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Telecommunication networks will transform and gradually migrate into virtualized cloud environments as a result of the potential for higher profitability through reduced costs and increased revenues. The purpose of this thesis is to investigate architectural mechanisms for location-independent communication between software components in a virtualized base station. Systems that provide such mechanisms are typically referred to as middleware and deployed as Platform-as-a-Service (PaaS). The overall goal is to achieve desired characteristics in cloud deployment regarding ondemand self-service, rapid elasticity of capacity while upholding services and high availability. Four communication protocols are examined and evaluated based on a set of functional and nonfunctional requirements that are especially relevant for a virtualized base station. In comparison with the Advanced Message Queuing Protocol (AMQP), Message Queuing Telemetry Transport (MQTT) and the eXtensible Messaging and Presence Protocol (XMPP), the Data Distribution Service (DDS) standard is found to have excellent performance characteristics. Its complexity might have implications for the development and deployment though, that will increase the time it takes to reap the benefits from its advantages.

  • Nilsson, Petter
    Umeå University, Faculty of Science and Technology, Department of Computing Science.
    Nilsson, Petter
    Umeå University, Faculty of Science and Technology, Department of Computing Science.
    Improving Data Quality in Swedbank Swedish DataWarehouse2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Poor data quality is very much present in large organizational databases

    worldwide, such as data warehouses (DWs). The purpose of this thesis

    is to propose improvements in how data quality issues are handled in

    Swedbank Swedish Data Warehouse. The thesis starts with a general explanation of what a DW is and what usage areas it has. After that, the concept of data quality and its dimensions is examined. Typical issues with data quality that may arise and how to solve them are covered. Swedbank’s architecture is described, along with the problems they face, and how they try to handle them as of now. Finally, improvement areas in their methods are highlighted, and general strategies, based on done research, for avoiding data quality issues are proposed. Hopefully, the propositions given in this thesis can be of use to others facing similar issues.

  • Lindström, Stefan
    Umeå University, Faculty of Science and Technology, Department of Computing Science.
    Lindström, Stefan
    Umeå University, Faculty of Science and Technology, Department of Computing Science.
    Generation of personal data for test persons for use in the Swedish Tax Agency’s Population Registry: An application of Context Free Grammar2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    When software systems grow large, the need for testing becomes more and more apparent the bigger the system becomes. These systems usually require data to be tested with. The acquisition of this data can be very time-consuming and thus, expensive. This is especially true if the data needs to be reacquired or otherwise changed every so often. This thesis will look at context-free grammars as a tool to generate the data required for testing the Swedish Tax Agency’s Population Registry with the purpose to reduce the time and effort to acquire new data.

  • Public defence: 2016-12-21 09:00 Hörsal D Unod T 9, Umeå
    Jashari, Haki
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Jashari, Haki
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    The effect of pressure afterload due to aortic coarctation on left ventricular function in children2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Background:

    Coarctation of the aorta (CoA) is a congenital heart disease which represents a narrowing of the proximal descending aorta, hence increasing pressure afterload to the left ventricle (LV). Conventional treatment of native CoA is surgical repair, however potential recurrence or other related complications e.g. aortic rupture, heart failure and cerebrovascular events are common. Thus, lifelong follow-up of these patients is required. Echocardiography is the most patient’s friendly method to evaluate CoA and in particular its effect on LV function. Moreover, the novel speckle tracking echocardiography (STE) is an important method to assess subclinical LV dysfunction, a technique that promises better evaluation of LV function in these patients.

    The aims of this thesis were to review the literature on LV function in children with CoA using myocardial deformation imaging technologies, hence, to better understand the current knowledge and vagueness of the scientific evidence. We also aimed to study the effect of early CoA repair on the structure and function of LV and ascending aorta. In addition, we wished to establish in a meta-analysis format normal values of speckle tracking derived strain and strain rate values.

    Methods:

    Study 1. We have systematically searched the PubMed, and studies that fulfilled the inclusion criteria were critically analyzed and presented on a narrative form.

    Study 2 and 3. In addition to conventional echocardiographic measures of LV and ascending aorta, we measured longitudinal strain and strain rate of the LV using a vendor independent software, TomTec. We have also measured the aorto-septal angle (AoSA). Data was compared with normal healthy controls.

    Study 4. Electronic databases were systematically searched and suitable studies were meta analyzed using Comprehensive meta-analysis version 3 software.

    Results:

    Study 1. In 7/4945 included articles, 123 and 76 patients with congenital aortic stenosis (CAS) and CoA were reported, respectively. Normal conventional LV function, with subclinical myocardial dysfunction were reported in all studies before intervention. After intervention, a consistent improvement of myocardial deformation parameters was documented, even though not reaching normal values.

    Study 2. In 21 patients with CoA, LV function significantly improved after intervention (p <0.001), however normal values were not reached even at medium-term follow-up (p = 0.002). Medium-term longitudinal strain correlated with pre intervention LV ejection faction (EF) (r = 0.58, p = 0.006). Medium-term subnormal values were more frequently associated with Bicuspid aortic valve (BAV) (33.3% vs. 66.6%; p <0.05).

    Study 3. AoSA was abnormally wide before intervention, in particular at peak ejection in the descending aorta (p <0.0001), and correlated with CoA pressure gradient. After intervention, AoSA normalized and significantly correlated with the increase of LV cavity function and overall LV deformation parameters.

    Study 4. In a meta-analysis of 28/282 studies including 1192 subjects, strain and strain rate values were established. Longitudinal strain normal mean values varied from -12.9 to -26.5 (mean, -20.5; 95 % CI, -20.0 to -21.0). Normal mean values of circumferential strain varied from -10.5 to -27.0 (mean, -22.06; 95 % CI, -21.5 to -22.5). Radial strain normal mean values varied from 24.9 to 62.1 (mean, 45.4; 95 % CI, 43.0 to 47.8). Meta-regression showed LV end-diastolic diameter as a significant determinant of variation of longitudinal strain. Longitudinal systolic strain rate was significantly determined by age and radial strain was influenced by the type of vendor used.

    Conclusion:

    The systematic review showed subclinical LV dysfunction in children with CoA before and after correction. However, since most of the patients were operated at an older age and had preserved LV EF, the effect of early intervention on LV function was only speculated. Our children with CoA who were operated at an earlier age showed LV subclinical dysfunction even at medium- term after intervention while the AoSA returned to normal shortly after intervention. Lower longitudinal strain values were found in patients with LV dysfunction (LV EF <50%) before intervention and BAV. Finally, normal range values for strain and strain rate have been established and seem to be influenced by patients’ age, LV end-diastolic diameter and vendor used.

  • Christensen, Stine Holmegaard
    et al.
    Christensen, Stine Holmegaard
    Timm, Signe
    Janson, Christer
    Benediktsdóttir, Bryndis
    Forsberg, Bertil
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Occupational and Environmental Medicine.
    Holm, Mathias
    Jogi, Rain
    Johannessen, Ane
    Omenaas, Ernst
    Sigsgaard, Torben
    Svanes, Cecilie
    Schlünssen, Vivi
    A clear urban-rural gradient of allergic rhinitis in a population-based study in Northern Europe.2016In: European clinical respiratory journal, ISSN 2001-8525, Vol. 3, 33463Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: The protective effect of farm upbringing on allergic rhinitis is well known, but how upbringing in other environments influences the development of allergic rhinitis is scarcely investigated. The aim of this study was to investigate the association between place of upbringing and pet keeping in childhood and allergic rhinitis and nasal symptoms in adulthood.

    METHODS: The population-based Respiratory Health in Northern Europe study includes subjects from Denmark, Norway, Sweden, Iceland, and Estonia born in 1945-1973. This paper analyses 13,376 participants of the third study wave. Six categories of place of upbringing were defined: farm with livestock, farm without livestock, village in rural area, small town, city suburb, and inner city. Pets in the home at birth and during childhood were recorded. Data were analysed using adjusted logistic regression models.

    RESULTS: Livestock farm upbringing predicted less adult allergic rhinitis [odds ratio (OR) 0.68, 0.54-0.85] and nasal symptoms (OR 0.82, 0.68-0.99) than city upbringing, and an urban-rural gradient with decreasing risk per level of urbanisation was observed (OR 0.92, 0.88-0.94). Pets in the home at birth (OR 0.78, 0.68-0.88) and during childhood (OR 0.83, 0.74-0.93) were associated with less subsequent allergic rhinitis. Pet keeping did not explain the protective effect of place of upbringing.

    CONCLUSION: Risk of allergic rhinitis and nasal symptoms in adulthood was inversely associated with the level of urbanisation during upbringing. Pets at birth decreased the risk further, but did not explain the urban-rural gradient. Persistent beneficial effects of microbial diversity in early life might be an explanation for the findings.

  • Jakobsson, Anton
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Jakobsson, Anton
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Energibesparing i industrilokal: En IDA ICE studie2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Reducing the energy consumption in older buildings is growing to be more important by each passing day as the cost of energy rises and political strides are made to limit the amount of energy used for various purposes. To optimize the use of energy in a building can be described as getting the same end result with a lower amount of spent energy, for the user this is an economic victory as he doesn’t have to spend as much money on heating his building while society gains a reduced impact on the environment and climate. In this thesis that you hold in your hands I have investigated an industrial building located in Teg, Umeå where I utilized the simulation software IDA ICE to simulate the buildings energy usage and the effects of various energy optimization/saving measures if implemented. The measures simulated are: Additional insulation for walls and roof, the switch to a ventilation system with a heat recovery unit, switching to well insulated windows, and switching the doors and garage doors to well insulated units.

    The work has mostly been done through studies of literature and IDA ICE where a model of the building has been constructed according to the specifications of the real world counterpart. The results from the various simulations are then compared with each other and the reference case.

    The results showed that all energy saving measures would result in a lowered use of energy. The biggest saving was gained from the changing out the ventilation system which resulted in a 49,3 % reduction whilst changing windows only resulted in a 0,7 % reduction.

  • Olsen, Jens
    et al.
    Umeå University, Faculty of Medicine, Department of Odontology.
    Olsen, Jens
    Umeå University, Faculty of Medicine, Department of Odontology.
    Muhrbeck, Torsten
    Umeå University, Faculty of Medicine, Department of Odontology.
    Surgical Removal of Ameloblastoma and Keratocystic Odontogenic Tumors in Maxilla and Mandible, a Literature Review on Surgical Techniques and Risk of Recurrence2016Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This literature review examines the literature on surgical management of ameloblastoma and keratocystic odontogenic tumours (KCOT). KCOT represent 3 % - 11 % of all the cystic lesions in the jaws and ameloblastoma 11 % of the odontogenic tumours. Treatment involves removal of the tumours by means of enucleation, curettage, marsupialization or resection. The first three can be combined with each other or with the adjunctive therapies: applications of Carnoy´s solution or cryotherapy. The aim of this literature review is to evaluate the risk of complications correlated to different surgical techniques for removal of KCOT or ameloblastoma.

    A search was performed in PubMed based on our keywords (Marsupialization, decompression, fenestration, enukleation, KCOT, OKC, KOT, keratocystic odontogenic tumor, odontogenic keratocyst, ameloblastoma, outcome, follow-up, relapse, prognosis, recurrence). The data was managed with Excel. 

    Twenty articles met our criteria: 12 articles reported KCOT in 667 patients and 8 articles reported 191 patients concerning Ameloblastoma.

    The articles almost exclusively presented the risk of recurrence for different treatment modalities. Subsequently the results mainly contain recurrence rates for different surgical techniques.

    412 KCOT patients received enucleation alone and 92 recurred, resulting in a recurrence rate of 22.3 %. 91 patients with ameloblastoma received resection and four recurred, resulting in a recurrence rate of 4.4 %.

    This review fails to identify any reliable evidence on recurrence rates in relation to treatment modalities for KCOT and ameloblastoma. Further prospective controlled clinical trials are essential to address this important issue.

  • Ottosson, Sverker
    Umeå University, Faculty of Arts, Department of historical, philosophical and religious studies.
    Ottosson, Sverker
    Umeå University, Faculty of Arts, Department of historical, philosophical and religious studies.
    1600-talets Sjuhundrads häradsting ur ett genusperspektiv2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • Public defence: 2016-12-16 13:00 Hörsalen, Östersunds sjukhus (Snäckan, ingång 6), Östersund
    Granbom, Elin
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Granbom, Elin
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Respiratory tract infections in children with congenital heart disease2016Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Respiratory Syncytial Virus (RSV) infection is common among young children. Congenital Heart Disease (CHD) is a risk factor of severe illness and hospitalization. Palivizumab prophylaxis reduces the severity of RSV infection and reduces the risk of hospitalization for children at high risk of severe illness, such as children born premature or with CHD.

    The aim of this thesis was to evaluate compliance with national guidelines for prophylactic treatment and to study the Relative Risk (RR) of hospitalization due to RSV and unspecified Respiratory Tract Infection (RTI) for children with CHD.

    In a prospective study, questionnaires were sent to all paediatric cardiology centres in Sweden with questions about prophylactic treatment. Hospitalization rates were retrieved from the national inpatient registry. Heart defects were grouped according to type and the relative risk of hospitalization was calculated for each group and for summer and winter seasons.

    Half of the patients received prophylactic treatment later than recommended in the guidelines. The risk of hospitalization due to RSV infection was increased (RR=2.06 95% CI 1.6-2.6; p < 0.0001) for children with CHD compared to children without CHD. The RR of hospitalization was also increased for all CHD subgroups, and was further increased during summer for children with the more severe CHD.

    We conclude that guidelines for prophylactic treatment were not followed and that the risk of hospitalization due to RSV and unspecified RTI was increased for all subgroups of CHD. The risk was increased both during winter and summer and we therefore argue that information to health personnel and parents should include that the risk of severe RTI is present all year round for children with CHD. 

  • Bränberg, Stefan
    Umeå University, Faculty of Science and Technology, Department of Computing Science.
    Bränberg, Stefan
    Umeå University, Faculty of Science and Technology, Department of Computing Science.
    Computing network centrality measures on fMRI data using fully weighted adjacency matrices2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A lot of interesting research is currently being done in the field of neuroscience, a recent subject being the effort to analyse the the human brain connectome and its functional connectivity. One way this is done is by applying graph-theory based network analysis, such as centrality, on data from fMRI measurements. This involves creating a graph representation from a correlation matrix containing the correlations over time between all measured voxels. Since the input data can be very big, this results in computations that are too memory and time consuming for an ordinary computer. Researchers have used different techniques to work around this problem, examples include thresholding correlations when creating the adjacency matrix and using a smaller input data with lower resolution.This thesis proposes three ways to compute two different centrality measures, degree centrality and eigenvector centrality, on fully weighted adjacency matrices that are built from complete correlation matrices computed from high resolution input data. The first is reducing the problem by doing the calculations in optimal order and avoiding the construction of the large correlation matrix. The second solution is to distribute and do the computations in parallel on a large computer cluster using MPI. The third solution is to calculate as large sets as possible on an ordinary laptop using shared-memory parallelism with OpenMP. Algorithms are presented for the different solutions, and the effectiveness of the implementations of them is tested.

  • Sundin, Karin
    et al.
    Umeå University, Faculty of Medicine, Department of Nursing.
    Sundin, Karin
    Umeå University, Faculty of Medicine, Department of Nursing.
    Bäckström, Britt
    Lindh, Viveca
    Umeå University, Faculty of Medicine, Department of Nursing.
    Lindkvist, Marie
    Umeå University, Faculty of Social Sciences, Umeå School of Business and Economics (USBE), Statistics.
    Saveman, Britt-Inger
    Umeå University, Faculty of Medicine, Department of Nursing.
    Östlund, Ulrika
    Responses after participating in Family Health Conversations in families with a family member who has suffered a stroke: A mixed methods research study2016In: Clinical Nursing Studies, ISSN 2324-7940, E-ISSN 2324-7959, Vol. 4, no 4, 46-57 p.Article in journal (Refereed)
    Abstract [en]

    Background: It has been proposed that support for families in which a family member has suffered a stroke should involve the whole family system. Aim: The aim was to evaluate the responses of Family Health Conversation (FamHC) in families with a member under the age of 65 who has been diagnosed with stroke. Methods: In this mixed methods research study, families were included in an intervention group and in a control group. For both groups pre- and post-intervention quantitative data was collected and for the intervention group, qualitative data was collected post-intervention. Underlying theoretical propositions and the two data sets were then integrated. Results: Family health measured as “the general atmosphere of the interaction of the family” had improved in the intervention group when compared to the control group. The intervention families, moreover, described how they had become more cooperative, their communication had improved, they had become more confident with their situation and also when planning for the future when comparing to before the FamHC. Conclusions: Based on the empirical results supporting the theoretical proposition underlying FamHC, we conclude that it works as intended, and the evidence for the theoretical proposition is thereby strengthened. This paper contributes to the scientific evidence concerning FamHC. With the available evidence, RNs are suggested to consider changing practice so as to work in a more family-centred way to support families living with ill-health. Implementing FamHC can be one way of undertaking such supportive work.

  • Public defence: 2016-12-16 10:00 Lilla hörsalen, Umeå
    Hedström, Per
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Hedström, Per
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Climate change impacts on production and dynamics of fish populations2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Ongoing climate change is predicted to increase water temperatures and export of terrestrial dissolved matter (TDOM) to aquatic ecosystems influencing ecosystem productivity, food web dynamics and production of top consumers. Ecosystem productivity is mainly determined by the rates of primary production (GPP) in turn controlled by nutrients, light availability and temperature, while temperature alone affect vital rates like consumption and metabolic rates and maintenance requirements of consumers. Increased level of TDOM causes brownification of water which may cause light limitation in algae and decrease GPP and especially so in the benthic habitat. Temperature increase has a been suggested to increase metabolic rates of consumers to larger extent than the corresponding effect on GPP, which suggest reduced top consumer biomass and production with warming.

    The aim of this thesis was to experimentally study the effects of increased temperature and TDOM on habitat specific and whole ecosystem GPP and fish densities and production. In a replicated large-scale pond experiment encompassing natural food webs of lotic ecosystems I studied population level responses to warming and brownification in the three- spined stickleback (Gasterosteus aculeatus).

    Results showed overall that warming had no effect on whole ecosystem GPP, likely due to nutrient limitation, while TDOM input decreased benthic GPP but stimulated pelagic GPP. In fish, results first of all suggested that recruitment in sticklebacks over summer was negatively affected by warming as maintenance requirements in relation to GPP increased and thereby increased starvation mortality of young-of-the-year (YOY) sticklebacks. Secondly, brownification increased mortality over winter in YOY as the negative effect on light conditions likely decreased search efficiency and caused lower consumption rates and starvation over winter in sticklebacks. Third, seasonal production of YOY, older, and total stickleback production was negatively affected by warming, while increased TDOM caused decreased YOY and total fish production. The combined effect of the two was intermediate but still negative. Temperature effects on fish production were likely a result of increased energy requirements of fish in relation to resource production and intake rates whereas the negative effect of TDOM likely was a result of decreased benthic resource production. Finally, effects of warming over a three-year period caused total fish density and biomass and abundance of both mature and old fish to decrease, while proportion of young fish increased. The main cause behind the strong negative effects of warming on fish population biomass and changes in population demographic parameters were likely the temperature driven increased energy requirements relative to resource production and cohort competition.

    The results from this thesis suggest that predicted climate change impacts on lentic aquatic ecosystems will decrease future densities and biomass of fish and negatively affect fish production and especially so in systems dominated by benthic resource production.

  • Public defence: 2016-12-16 09:00 E04, Umeå
    Song, Jie
    Umeå University, Faculty of Medicine, Department of Medical Biosciences.
    Song, Jie
    Umeå University, Faculty of Medicine, Department of Medical Biosciences.
    Non-canonical TGFb signaling pathways in prostate cancer2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Prostate cancer is the second leading cause of cancer-related death in men in the Western world. Deregulation of transforming growth factor β (TGFβ) signaling pathway is frequently detected in prostate cancer and contributes to tumor growth, migration, and invasion. In normal tissue and the early stages of cancer, TGFβ acts as a tumor suppressor by regulating proliferation, differentiation, and apoptosis. In later stages of cancer, TGFβ acts as a tumor promoter by inducing angiogenesis, tumor invasion, and migration. Thus, it is important to investigate the molecular mechanisms behind the tumor-promoting effects of TGFβ, which is the topic of this thesis.

     

    The tumor necrosis factor receptor–associated factor 6 (TRAF6) controls non-canonical TGFβ signals due to its enzymatic activity, causing polyubiquitination of the cell membrane–bound, serine/threonine kinase TGFβ type I receptor (TβRI) and its subsequent cleavage in the extracellular domain by tumor necrosis factor a–converting enzyme (TACE) in a protein kinase C ζ (PKCζ)-dependent manner. TRAF6 also recruits the active g-secretase complex to the TβRI, resulting in a second cleavage in the transmembrane region and the liberation of the TβRI intracellular domain (TβRI-ICD), which enters the nucleus, where it associates with the transcriptional co-regulator p300. In Paper I, the aim was to elucidate by which mechanisms TβRI-ICD enters the nucleus. We found that the endocytic adaptor protein APPL1 interacts with TβRI and PKCζ. APPL proteins are required for TβRI translocation from endosomes to the nucleus via microtubules in a TRAF6-dependent manner. Moreover, APPL proteins are important for TGFβ-induced cell invasion, and high levels of APPL1 are detected by immunohistochemistry in prostate cancer. Finally, we demonstrated that the APPL1–TβRI complex visualized with the in situ proximity ligation assay (PLA) correlates with Gleason score, indicating that it might be a novel prognostic marker for aggressive prostate cancer. In Paper II, the aim was to explore by which mechanisms TGFβ causes activation of the AKT pathway, which regulates migration and therapy resistance of cancer cells. We found that the E3 ligase activity of TRAF6 induces Lys63-linked polyubiquitination of p85α upon TGFβ stimulation, resulting in plasma membrane recruitment, Lys63-linked polyubiquitination, and subsequent activation of AKT. Moreover, the TRAF6 and PI3K/AKT pathway were found to be crucial for the TGFβ-induced migration. Importantly, we demonstrated, by PLA, a correlation between Lys63-linked polyubiquitination of p85α and aggressive prostate cancer in tissue sections from patients with prostate cancer. In Paper III, the aim was to investigate the mechanisms for TGFβ-induced activation of PKCζ and the role of PKCζ in tumor regression. We found that TRAF6 caused Lys63-linked polyubiquitination of PKCζ. By using two novel chemical compounds that inhibit PKCζ, we demonstrated that PKCζ is crucial for prostate cancer cell survival and invasion. In Paper IV, the aim was to investigate further the target genes for the nuclear TβRI-ICD-APPL1 complex identified in Paper I. We provide evidence that APPL proteins and the TGFβ signaling pathway are important for cell proliferation. In summary, the results reported in this thesis suggest the potential usefulness of the identified signaling components of the tumor-promoting effects of TGFβ as drug targets and biomarkers for aggressive prostate cancer. 

  • Public defence: 2016-12-16 10:00 Major Groove, Biomedicinhuset, Byggnad 6L, Umeå
    Avican, Ummehan
    Umeå University, Faculty of Medicine, Umeå Centre for Microbial Research (UCMR). Umeå University, Faculty of Medicine, Molecular Infection Medicine Sweden (MIMS). Umeå University, Faculty of Science and Technology, Department of Molecular Biology (Faculty of Science and Technology).
    Avican, Ummehan
    Umeå University, Faculty of Medicine, Umeå Centre for Microbial Research (UCMR). Umeå University, Faculty of Medicine, Molecular Infection Medicine Sweden (MIMS). Umeå University, Faculty of Science and Technology, Department of Molecular Biology (Faculty of Science and Technology).
    Twin-arginine translocation in Yersinia: the substrates and their role in virulence2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Pathogenic Yersinia cause a manifold of diseases in humans ranging from mild gastroenteritis (Y. pseudotuberculosis and Y. enterocolitica) to pneumonic and bubonic plague (Y. pestis), while all three have a common virulence strategy that relies on a well-studied type III secretion system and its effector proteins to colonize the host and evade immune responses. However, the role of other protein secretion and/or translocation systems in virulence of Yersinia species is not well known. In this thesis, we sought to investigate the contribution of twin-arginine translocation (Tat) pathway and its secreted substrates to the physiology and virulence of Y. pseudotuberculosis. Tat pathway uniquely exports folded proteins including virulence factors across the cytoplasmic membranes of bacteria. The proteins exported by Tat pathway contain a highly conserved twin-arginine motif in the N-terminal signal peptide. We found that the loss of Tat pathway causes a drastic change of the transcriptome of Y. pseudotuberculosis in stationary phase at environmental temperature with differential regulation of genes involved in virulence, carbon metabolism and stress responses. Phenotypic analysis revealed novel phenotypes of the Tat-deficient strain with defects in iron acquisition, acid resistance, copper oxidation and envelope integrity, which we were partly able to associate with the related Tat substrates. Moreover, increased glucose consumption and accumulation of intracellular fumarate were observed in response to inactivation of Tat pathway implicating a generic effect in cellular physiology. We evaluated the direct role of 22 in silico predicted Tat substrate mutants in the mouse infection model and found only one strain, ΔsufI, exhibited a similar degree of attenuation as Tat-deficient strain. Comparative in vivo characterization studies demonstrated a minor defect for ΔsufI in colonization of intestinal tissues compared to the Tat-deficient strain during early infection, whereas both SufI and TatC were required for dissemination from mesenteric lymph nodes and further systemic spread during late infection. This verifies that SufI has a major role in attenuation seen for the Tat deficient strain both during late infection and initial colonization. It is possible that other Tat substrates such as those involved in iron acquisition and copper resistance also has a role in establishing infection. Further phenotypic analysis indicated that SufI function is required for cell division and stress-survival. Transcriptomic analysis revealed that the highest number of differentially regulated genes in response to loss of Tat and SufI were involved in metabolism and transport. Taken together, this thesis presents a thorough analysis of the involvement of Tat pathway in the overall physiology and virulence strategies of Y. pseudotuberculosis. Finally, we propose that strong effects in virulence render TatC and SufI as potential targets for development of novel antimicrobial compounds

  • Public defence: 2016-12-16 09:00 Room 135, Family Medicine, Building 9A, Umeå
    Godefay Debeb, Hagos
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Epidemiology and Global Health.
    Godefay Debeb, Hagos
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Epidemiology and Global Health.
    Maternal Mortality Then, Now, and Tomorrow: The Experience of Tigray Region, Northern Ethiopia2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Abstract

    Background: Maternal mortality is one of the most sensitive indicators of the health disparities between poorer and richer nations. It is also one of the most difficult health outcomes to measure reliably. In many settings, major challenges remain in terms of both measuring and reducing maternal mortality effectively. This thesis aims to quantify overall levels, identify specific causes, and evaluate local interventions in relation to efforts to reduce maternal mortality in Tigray Region, Northern Ethiopia, thereby providing a strong empirical basis for decision making by the Tigray Regional Health Bureau using methods that can be scaled at national level.

     

    Methods: This study employed a combination of community-based study designs to investigate the level and determinants of maternal mortality in six randomly selected rural districts of Tigray Region. A census of all households in the six districts was conducted to identify all live births and all deaths to women of reproductive age occurring between May 2012 and September 2013. Pregnancy-related deaths were screened through verbal autopsy with the data processed using the InterVA-4 model, which was used to estimate Maternal Mortality Ratio. To identify independent determinants of maternal mortality, a case-control study using multiple logistic regression analysis was done, taking all pregnancy-related deaths as cases and a random sample of geographical and age matched mothers as controls. Uptake of ambulance services in the six districts was determined retrospectively from ambulance logbooks, and the trends in pregnancy-related death were analyzed against ambulance utilization, distance from nearest health center, and mobile network coverage at local area level. Lastly, implementation of the Family Folder paper health register, and its potential for accurately capturing demographic and health events, were evaluated using a capture-recapture assessment.

     

    Results: A total of 181 deaths to women of reproductive age and 19,179 live births were documented from May 2012 to April2013. Of the deaths, 51 were pregnancy-related. The maternal mortality ratio for Tigray region was calculated at 266 deaths per 100,000 live births (95% CI 198-350), which is consistently lower than previous “top down” MMR estimates. District–level MMRs showed strong inverse correlation with population density (r2 = 0.86). Direct obstetric causes accounted for 61% of all pregnancy–related deaths, with hemorrhage accounting for 34%. Non-membership in the voluntary Women’s Development Army (AOR 2.07, 95% CI 1.04-4.11), low husband or partner involvement during pregnancy (AOR 2.19, 95% CI 1.14-4.18), pre-existing history of other illness (AOR 5.58, 95% CI 2.17-14.30), and never having used contraceptives (AOR 2.58, 95% CI 1.37-4.85) were associated with increased risk of maternal death in a multivariable regression model. In addition, utilization of free ambulance transportation service was strongly associated with reduced MMR at district level. Districts with above-average ambulance utilization had an MMR of 149 per 100,000 LB (95% CI: 77-260) compared with 350 per 100,000 (95% CI: 249-479) in districts with below average utilization. The Family Folder implementation assessment revealed some inconsistencies in the way Health Extension Workers utilize the Family Folders to record demographic and health events.

     

    Conclusion: This work contributes to understanding the status of and factors affecting maternal mortality in Tigray Region. It introduces a locally feasible approach to MMR estimation and gives important insights in to the effectiveness of various interventions that have been targeted at reducing maternal mortality in recent years.

  • Public defence: 2016-12-16 13:00 Hörsal B, målpunkt A, 9 trappor, Umeå
    Franklin, Oskar
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Franklin, Oskar
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Stromal components and micro-RNAs as biomarkers in pancreatic cancer2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Background Pancreatic ductal adenocarcinoma (PDAC) patients have the poorest 5-year survival rates of all cancer forms. It is difficult to diagnose at early disease stages, tumour relapse after surgery is common, and current chemotherapies are ineffective. Carbohydrate antigen 19-9 (Ca 19-9), the only clinically implemented PDAC biomarker, is insufficient for diagnostic and screening purposes.

    PDAC tumours are characterised by a voluminous stroma that is rich in extracellular matrix (ECM) molecules such as collagens, hyaluronan (HA) and matricellular proteins. These stromal components have been suggested to promote PDAC cell migration, proliferation, evasion of apoptosis and chemotherapy resistance. Those events are mediated via interactions with adhesion receptors, such as integrins and CD44 receptors expressed on cancer cell surfaces.

    Micro-RNAs (miRNA) post-transcriptionally regulate gene expression in health and disease. At the time of PDAC diagnosis, miRNA levels are altered both in plasma and tumour tissue. Before PDAC diagnosis, tissue miRNA levels are altered in precursor lesions, raising the possibility that plasma miRNAs might aid in early detection.

    In this thesis, it is hypothesised that stromal components and miRNAs can serve as tissue or blood based biomarkers in PDAC. The aims are: (1) to characterise the expression of stromal components and their receptors in normal and cancerous tissue; (2) to find potential stroma-associated tissue and blood-based biomarkers for diagnosis and prognosis estimates; (3) to determine the cellular effects of type IV collagen (Col IV) in PDAC; (4) to determine if plasma miRNAs that are altered in manifest PDAC can be used to diagnose PDAC earlier.

    Methods The expression patterns of Col IV, Col IV-binding integrin subunits (α1, α2, β1), Endostatin, Osteopontin (OPN) and Tenascin C (TNC) were analysed in frozen PDAC and normal pancreatic tissue. A tissue microarray (TMA) was constructed using formalin-fixed, paraffin-embedded primary tumours and lymph node metastases. The TMA was used to study the expression levels and associations with survival of the standard CD44 receptor (CD44s), its variant isoform 6 (CD44v6), HA, OPN and Col IV. Circulating levels of HA, Col IV, Endostatin, OPN and TNC were measured in PDAC patients and healthy individuals, and compared with conventional tumour markers (Ca 19-9, CEA, Ca 125 and TPS). The functional roles of Col IV were studied in PDAC cell lines by: (1) growth on different matrices (2) blocking Col IV binding integrin subunits, (3) blocking the Col IV domains 7s, CB3 and NC1, and (4) by down regulation of PDAC cell synthesis of Col IV using siRNA transfection. Plasma miRNAs alterations were screened for in samples from patients with manifest disease, using real-time quantitative PCR (RT-qPCR). To find early miRNA alterations, levels of those miRNAs that were altered at diagnosis were measured in prediagnostic plasma samples.

    Results High tissue expression of both the standard CD44 receptor (CD44s) and its variant isoform CD44v6 as well as low expression of stromal OPN were associated with poor survival. In addition, high CD44s and low OPN predicted poor survival independent of established prognostic factors.

    Circulating Col IV, Endostatin, OPN, TNC and HA were increased in preoperative samples from PDAC patients. Preoperatively, higher levels of serum-HA and plasma-Endostatin were associated with shorter survival. Postoperatively, higher levels of Col IV, Endostatin and OPN were associated with shorter survival. On the contrary, only one of the conventional tumour markers was associated with survival (Ca 125).

    Col IV stimulated PDAC cell proliferation and migration and inhibited apoptosis in vitro, dependent on the collagenous domain (CB3) of Col IV and the Col IV binding integrin subunit β1. Reduced endogenous Col IV synthesis inhibited these effects, suggesting that PDAC cells synthesise Col IV to stimulate tumour-promoting events via a newly discovered autocrine loop.

    15 miRNAs were altered in early stage PDAC patients and the combination of these markers outperformed Ca 19-9 in discriminating patients from healthy individuals. However, none of the miRNAs were altered in prediagnostic samples, suggesting that plasma miRNA alterations appear late in the disease course.

    Conclusions Up regulated stromal components in PDAC tumours are detectable in blood samples and are potential diagnostic and prognostic biomarkers in PDAC. High circulating levels of Col IV, Endostatin, OPN and HA predict poor survival, as well as high expression of CD44s and CD44v6 and low expression of OPN in tumour tissue. PDAC cells synthesise Col IV, which forms BM-like structures close to cancer cells and promote tumour progression in vitro via an autocrine loop. Several plasma-miRNAs are altered in PDAC, but are not useful for early discovery. 

  • Sundqvist, Elin
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Sundqvist, Elin
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    En översiktlig miljöteknisk markundersökning: En fallstudie för att undersöka dioxinförekomst vid en nedlagd sågverksamhet i Lövsele, Västerbottens län2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Sawmills which conducted dipping operations is a breach where previously used chemicals mean that you generally can expect to find contaminated areas. To investigate contaminated areas the Swedish environmental protection agency developed a method for investigation of polluted areas (MIFO). The purpose of a MIFO analysis is to provide a unified approach and risk classification system for polluted areas. The aim of this thesis it to perform a soil survey according to MIFO phase 2 (general investigations) at the former sawmill in Lövsele, Västerbotten county. The study is based on assumptions about the presence of dioxins in the area, due to the previous use of the wood preservative Ky-5. Dioxins are dangerous substances and are considered poisonous for both humans and the environment. The field study was conducted 30 September 2016 in 8 selected points where the greatest risk to find dioxins were considers to exist after completion of background investigations. 9 samples were the chosen for analysis by ALS Scandinavia AB. The completed analysis shows that pollution levels above the guideline values of both sensitive land use (KM) and less sensitive land use (MKM) were discovered in 7 out of 9 analyzed samples. The MIFO analysis was conducted to answer questions about the pollution hazards, pollution level, distribution conditions and the sensitivity and protection value in the area. The result of the MIFO-analysis is evaluated as class 1, very high risk to human health and the environment. Further studies should therefore be conducted to determine the pollution situation in the area and to provide data for remediation measures to reduce the risk to human health and the environment.

  • van Woerkom, Anne
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    van Woerkom, Anne
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Ancient DNA from soils and sediments from the Krigstjärn area, northern Sweden: Preservation and detection of Holocene mammal sedaDNA2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Current knowledge of past vegetation and faunal diversity has been based on pollen and macrofossil analysis from lake sediments. The innovative method of sedimentary ancient DNA (sedaDNA) is a promising, complementary proxy to reconstruct information about past environments. However, to what extent animal DNA can be extracted from old sediments and soils has not been frequently studied. This study explored if ancient DNA of moose (Alces alces), reindeer (Rangifer tarangus), goat (Capra aegagrus) and plants could be extracted from millennia old lake sediments of Lake Krigstjärn and archaeological soil samples in northern Sweden. SedaDNA was successfully extracted and detected from both reindeer and plants DNA, while goats sedaDNA was absent in all sediments. Moose ancient DNA (aDNA) was only detected in the archaeological soils. Yet, there were signs that the applied moose primer set was not optimal for heavily degraded DNA and the validity of this primer needs further research. Earliest detections of reindeer DNA can be dated to ~6500 c. years ago. Oldest sediments contained DNA, indicating sufficient DNA preservation conditions in the sediments of Lake Krigstjärn. Finds of plants DNA in pre-deglaciational sediments may indicate the existence of >9500 year old glacial vegetation. Altogether is sedaDNA a highly promising tool to reconstruct diversity, origin and immigration routes of mammals, but technical issues such as primer set specificity and its purpose should be considered and tested carefully in advance. 

  • Ödling, Evelina
    et al.
    Umeå University, Faculty of Medicine, Department of Nursing.
    Ödling, Evelina
    Umeå University, Faculty of Medicine, Department of Nursing.
    Engström, Lovisa
    Umeå University, Faculty of Medicine, Department of Nursing.
    Erfarenheter av stigmatisering i hälso- och sjukvården bland personer som drabbats av HIV.: -en litteraturstudie2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Title: Experiences of stigma in health care among people affected by HIV- A literature review Background: HIV (Human Immunodeficiency Virus) has been associated with stigmatization for a long time because of ignorance and uncertainty still exists regarding the transmission routes and infectivity. Aim: The aim for the study was to highlight experiences of stigma in health care among people affected by HIV. Method: A literature study was conducted with ten qualitative articles from eight different countries. The articles were examined, analyzed and compiled. Results: The result generated two categories and five subcategories. The categories are: To be treated with a lack of care actions and experiences of integrity violation. The sub-categories are: excessive security measures, ignorant attitudes, lack of secrecy, offensive body language and abusive verbal communication.                                                                   Conclusion: Lack of knowledge about HIV can be seen internationally seen as a contributing factor to the patients still experiencing varying stigmatized treatment by health professionals. To counteract the stigma requires research that can generate knowledge on how health professionals can provide better treatment and that this information is disseminated to the medical staff. Keywords: HIV, stigmatization, patient-experience, discrimination.

  • Edholm, Miriam
    et al.
    Umeå University, Faculty of Medicine, Department of Nursing.
    Edholm, Miriam
    Umeå University, Faculty of Medicine, Department of Nursing.
    Westin, Lisett
    Umeå University, Faculty of Medicine, Department of Nursing.
    Anhörigas upplevelser när en familjemedlem flyttar till ett särskilt boende för äldre: Relatives’ experiences when a family member move to a residential home for older people2016Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Bakgrund: Omorganisation inom vården ställer högre krav på anhöriga då fler vårdas i hemmet. Därför behövs mer kunskap om anhörigas situation för att stärka familjehälsan. Syfte: Syftet med studien var att belysa hur anhöriga upplever sin situation i flyttprocessen före, under och efter flytten av en vårdbehövande familjemedlem till ett särskilt boende för äldre, vilket framkom vid hälsostödjande familjesamtal.

    Metod: Åtta familjer deltog i en samtalsserie av tre samtal. Samtalen analyserades med kvalitativ innehållsanalys.

    Resultat: Huvudresultatet visade på att före flytten upplevdes livssituationen som ohållbar med ett krävande ansvar. Under flytten upplevdes både känslor av frid och frustration. Efter flytten upplevdes sorg, varierat förtroende för boendet, att de anhöriga ville behålla relationen med den vårdbehövande och en förändrad familjesituation.

    Slutsats: Anhörigas upplevelser var varierande under flyttprocessen. Distriktsköterskan bör vara synlig och finnas som stöd.

  • Viberg, Tomas
    et al.
    Umeå University, Faculty of Medicine, Department of Nursing.
    Viberg, Tomas
    Umeå University, Faculty of Medicine, Department of Nursing.
    Blomquist, Ulrika
    Umeå University, Faculty of Medicine, Department of Nursing.
    Sjuksköterskors erfarenheter av att arbeta på svensk akutmottagning2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Bakgrund: På en akutmottagning ställs det höga krav på sjuksköterskans professionella kompetens och förmåga att anpassa bemötandet till olika patienter. Arbetet inriktas på att så snabbt och säkert som möjligt bedöma patienternas medicinska behov. Fokus på medicinska åtgärder och ett högt arbetstempo kan medföra minskade möjligheter att förstå eller bemöta patienternas specifika omvårdnadsbehov.

     

    Syfte: Att beskriva sjuksköterskors erfarenheter av att arbeta på akutmottagning i Sverige

     

    Metod:Litteraturstudie med åtta artiklar som alla hade en kvalitativ ansats. Artiklarna har granskats, analyserats och sammanställts.

     

    Resultat: Sjuksköterskan bedömer patienterna när de kommer till akutmottagningen och fortsätter att observera dem under vistelsen på akutmottagningen. Sjuksköterskorna på akutmottagningen arbetar ofta med många parallella uppgifter och ofta under tidspress och stress. Akutsjuksköterskors syn på omvårdnad i dessa studier förefaller vara väldigt praktiskt inriktad och omvårdnaden är ofta inte en prioriterad arbetsuppgift.

     

    Konklusion: Ett högt patientflöde och många arbetsuppgifter leder till att det blir lite tid till varje patient. Det korta mötet med patienten kan innebära att viktig information inte kommer fram. De medicinska uppgifterna prioriteras och omvårdnaden är något som är långt ner på den hierarkiska skalan av arbetsuppgifter.

  • Public defence: 2016-12-15 13:00 KB3A9, Umeå
    Yelhekar, Tushar
    Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB).
    Yelhekar, Tushar
    Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB).
    Chloride Homeostasis in Central Neurons2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The overall aim of the present thesis is to clarify the control of intracellular chloride homeostasis in central neurons, because of the critical role of chloride ions (Cl) for neuronal function. Normal function of the central nervous system (CNS) depends on a delicate balance between neuronal excitation and inhibition. Inhibition is, in the adult brain, most often mediated by the neurotransmitter γ-aminobutyric acid (GABA). GABA may, however, in some cases cause excitation. GABA acts by activating GABA type A receptors (GABAARs), which are ion channels largely permeable to Cl. The effect of GABAAR-mediated neuronal signaling - inhibitory or excitatory - is therefore mainly determined by the Cl gradient across the membrane. This gradient varies with neuronal activity and may be altered in pathological conditions. Thus, understanding Cl regulation is important to comprehend neuronal function. This thesis is an attempt to clarify several unknown aspects of neuronal Cl regulation. For such clarification, a sufficiently sensitive method for measuring the intracellular Cl concentration, [Cl]i, is necessary. In the first study of this thesis, we examined two electrophysiological methods commonly used to estimate [Cl]i. Both methods, here called the interpolation and the voltage-ramp method, depend on an estimate of the Cl equilibrium potential from the current-voltage relation of GABA- or glycine-evoked Cl currents. Both methods also provide an estimate of the membrane Cl conductance, gCl. With a combination of computational and electrophysiological techniques, we showed that the most common (interpolation) method failed to detect changes in [Cl]i and gCl during prolonged GABA application, whereas the voltage-ramp method accurately detected such changes. Our analysis also provided an explanation as to why the two methods differ. In a second study, we clarified the role of the extracellular matrix (ECM) for the distribution of Cl across the cell membrane of neurons from rat brain. It was recently proposed that immobile charges located within the ECM, rather than as previously thought cation-chloride transporter proteins, determine the low [Cl]i which is critical to GABAAR-mediated inhibition. By using electrophysiological techniques to measure [Cl]i, we showed that digestion of the ECM decreases the expression and function of the neuron-specific K+ Cl cotransporter 2 (KCC2), which normally extrudes Cl- from the neuron, thus causing an increase in resting [Cl]i. As a result of ECM degradation, the action of GABA may be transformed from inhibitory to excitatory. In a third study, we developed a method for quantifying the largely unknown resting Cl (leak) conductance, gCl, and examined the role of gCl for the neuronal Cl homeostasis. In isolated preoptic neurons from rat, resting gCl was about 6 % of total resting conductance, to a major part due to spontaneously open GABAARs and played an important role for recovery after a high Cl load. We also showed that spontaneous, impulse-independent GABA release can significantly enhance recovery when the GABA responses are potentiated by the neurosteroid allopregnanolone. In a final commentary, we formulated the mathematical relation between Cl conductance, KCC2-mediated Cl extrusion capacity and steady-state [Cl]i. In summary, the present thesis (i) clarifies how well common electrophysiological methods describe [Cl]i and gCl, (ii) provides a novel method for quantifying gCl in cell membranes and (iii) clarifies the roles of the ECM, ion channels and ion transporters in the control of [Cl]i homeostasis and GABAAR-mediated signaling in central neurons. 

  • Esmail, Shaymaa
    Umeå University, Faculty of Arts, Department of language studies.
    Esmail, Shaymaa
    Umeå University, Faculty of Arts, Department of language studies.
    Persuasion in Rhetoric: A Critical Metaphor Analysis of the Use of Metaphor in Pro-war Political Speeches2016Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This paper is investigating how metaphors are used in political speeches to achieve persuasion. By analyzing three speeches dealing with the Iraqi war 2003 and delivered by Bush, Blair and Howard, I try to find out the similarities and differences in how metaphors are constructed, how they are used as a persuasive technique, and lastly if the different military contribution of the three countries affected how metaphors are constructed. The main theory used in this study is Critical Metaphor Analysis suggested by Charteris-Black (2011). The analysis suggests that the speeches contain different kinds of metaphors like personification, the POLITICS IS BUSINESS metaphor and JOURNEY metaphors. Metaphors are generally found to be used in a similar way in order to show that the politicians are ‘right’. Still, there are some differences that could be attributed to the different military contribution of the countries and their different role in the war. 

  • Montoya, Luisa
    et al.
    Umeå University, Faculty of Medicine, Department of Odontology.
    Montoya, Luisa
    Umeå University, Faculty of Medicine, Department of Odontology.
    Åström, Emelie
    Umeå University, Faculty of Medicine, Department of Odontology.
    Knowledge of Oral Health in School Children aged 7-8 years2016Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Nationally an increased inequality in oral health is seen. Children coming from a lower socioeconomicbackground, as well as children with immigrant background show a higherprevalence of caries. The reason for this can be cultural differences but also parentalunawareness.In this study, the differences in knowledge and oral health habits of children aged 7-8 areinvestigated. The hypothesis is that an increased education and training of oral health inprimary school can help to provide a more equitable oral health in children, regardless oftheir background.Three schools where chosen for this study based on their representation of different socioeconomicareas. A total of 176 pupils participated in the study, where they were asked to fillout a questionnaire about their habits and knowledge of oral health. The same questionnairewas filled out at a later time after they had an educational session and illustrative teachingmaterial was handed out to all of the pupils. The results from the first and second sessionwere compared and analysed.This study shows that there are big differences in children’s oral habits and knowledge inbetween different schools depending on their socioeconomic level. Differences could also beseen depending on the children’s cultural background, as children with foreign-born parentshad a lower knowledge and in some aspects more lacking oral habits. It could also beconcluded that education in school had a positive impact on the children’s knowledge in oral health regardless of their background.

  • Muindi, Kanyiva
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Epidemiology and Global Health.
    Muindi, Kanyiva
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Epidemiology and Global Health.
    Kimani-Murage, Elizabeth
    Egondi, Thaddaeus
    Rocklöv, Joacim
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Epidemiology and Global Health.
    Ng, Nawi
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Epidemiology and Global Health.
    Household Air Pollution: Sources and Exposure Levels to Fine Particulate Matter in Nairobi Slums2016In: TOXICS, ISSN 2305-6304, Vol. 4, no 3, 12Article in journal (Refereed)
    Abstract [en]

    With 2.8 billion biomass users globally, household air pollution remains a public health threat in many low- and middle-income countries. However, little evidence on pollution levels and health effects exists in low-income settings, especially slums. This study assesses the levels and sources of household air pollution in the urban slums of Nairobi. This cross-sectional study was embedded in a prospective cohort of pregnant women living in two slum areasKorogocho and Viwandaniin Nairobi. Data on fuel and stove types and ventilation use come from 1058 households, while air quality data based on the particulate matters (PM2.5) level were collected in a sub-sample of 72 households using the DustTrak II Model 8532 monitor. We measured PM2.5 levels mainly during daytime and using sources of indoor air pollutions. The majority of the households used kerosene (69.7%) as a cooking fuel. In households where air quality was monitored, the mean PM2.5 levels were high and varied widely, especially during the evenings (124.6 mu g/m(3) SD: 372.7 in Korogocho and 82.2 mu g/m(3) SD: 249.9 in Viwandani), and in households using charcoal (126.5 mu g/m(3) SD: 434.7 in Korogocho and 75.7 mu g/m(3) SD: 323.0 in Viwandani). Overall, the mean PM2.5 levels measured within homes at both sites (Korogocho = 108.9 mu g/m(3) SD: 371.2; Viwandani = 59.3 mu g/m(3) SD: 234.1) were high. Residents of the two slums are exposed to high levels of PM2.5 in their homes. We recommend interventions, especially those focusing on clean cookstoves and lighting fuels to mitigate indoor levels of fine particles.

  • Rigard, Melanie
    et al.
    Rigard, Melanie
    Bröms, Jeanette E.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Bacteriology.
    Mosnier, Amandine
    Hologne, Maggy
    Martin, Amandine
    Lindgren, Lena
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Bacteriology.
    Punginelli, Claire
    Lays, Claire
    Walker, Olivier
    Charbit, Alain
    Telouk, Philippe
    Conlan, Wayne
    Terradot, Laurent
    Sjöstedt, Anders
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Bacteriology.
    Henry, Thomas
    Francisella tularensis IglG Belongs to a Novel Family of PAAR-Like T6SS Proteins and Harbors a Unique N-terminal Extension Required for Virulence2016In: PLoS Pathogens, ISSN 1553-7366, E-ISSN 1553-7374, Vol. 12, no 9, e1005821Article in journal (Refereed)
    Abstract [en]

    The virulence of Francisella tularensis, the etiological agent of tularemia, relies on an atypical type VI secretion system ( T6SS) encoded by a genomic island termed the Francisella Pathogenicity Island ( FPI). While the importance of the FPI in F. tularensis virulence is clearly established, the precise role of most of the FPI-encoded proteins remains to be deciphered. In this study, using highly virulent F. tularensis strains and the closely related species F. novicida, IglG was characterized as a protein featuring a unique alpha-helical N-terminal extension and a domain of unknown function ( DUF4280), present in more than 250 bacterial species. Three dimensional modeling of IglG and of the DUF4280 consensus protein sequence indicates that these proteins adopt a PAAR-like fold, suggesting they could cap the T6SS in a similar way as the recently described PAAR proteins. The newly identified PAAR-like motif is characterized by four conserved cysteine residues, also present in IglG, which may bind a metal atom. We demonstrate that IglG binds metal ions and that each individual cysteine is required for T6SS-dependent secretion of IglG and of the Hcp homologue, IglC and for the F. novicida intracellular life cycle. In contrast, the Francisella-specific N-terminal alpha-helical extension is not required for IglG secretion, but is critical for F. novicida virulence and for the interaction of IglG with another FPI-encoded protein, IglF. Altogether, our data suggest that IglG is a PAAR-like protein acting as a bi-modal protein that may connect the tip of the Francisella T6SS with a putative T6SS effector, IglF.

  • Public defence: 2016-12-14 13:00 N460, Naturvetarhuset, Umeå
    Nyström, Robin
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Nyström, Robin
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Particle emissions from residential wood and biodiesel combustion2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Emissions from anthropogenic combustion sources, such as vehicles and biomass combustion, contribute significantly to ambient particulate matter (PM) both on a local and global scale. Exposure to ambient PM and air pollution in general is linked to a variety of different health effects and it has been estimated that as many as 2.1 million premature deaths each year, due to cardiopulmonary disease and lung cancer, are caused by the changes in anthropogenic air pollution since pre-industrial times. There is today still a lack of information regarding the emissions of different specific particulate emission components, e.g. soot, polycyclic aromatic hydrocarbons (PAHs), oxy-PAHs combined with details about the behaviour of different fuels under varying combustion conditions. The overall objective of this work was to provide new knowledge regarding physical and chemical properties of PM from solid and liquid biofuels, which are important for the viewpoint of human health and atmospheric pollution. This was achieved by experimental studies of the combustion of biomass using a residential wood stove and by introducing biodiesel to an off-road engine, thereby investigating two major emission sources for PM and gaseous emissions.

    From the two papers regarding biodiesel included in this thesis, it can be concluded that the introduction of the biodiesel, and potentially other renewable fuels, can in a considerable way change the exhaust particle emissions. This could have implications for the assessment of exhaust from engines running on biodiesel fuels, especially when introducing biodiesel in existing and older engines.

    The results from the wood combustion research performed showed some important considerations regarding both specific particle properties and the influences of different burning conditions and fuels. One major finding, based on several of the included studies, was that a proper operation of a wood stove is of major importance to avoid unfavourable burning condition and elevated emissions of soot and organic particles, regardless of the wood species used. Some specific occasions during the burning phases in batch wise wood combustion were also identified as important for the overall emissions. The results from this research has given new specific insights into the emissions from wood stoves and should be of relevance for both technological development of residential appliances, emission testing/certification, information to users and legislation.

  • Waara, Stina
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Waara, Stina
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Tungmetaller i Mobekken: Spridning, risker och eventuella åtgärdsbehov2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report details the study of a freshwater stream carrying high doses of heavy metals into an already affected fjord. The purpose is to find out how the measured levels of heavy metals vary across the industrial area, and if these levels are posing an environmental or health threat to the surroundings. According to the water directive of the European Union, all waters should be protected in order to reach ’good status’, and deterioration should be prevented. To keep track of the status of waters, environmental quality standards (limit values known as EQS) are used by Norwegian environmental authorities to indicate pollution levels. All measured contents in this report are therefore compared with EQS or similar limit values. New water samples were taken along the stream and in the soil and sediments during the spring of 2016. The measured levels were then compared with older water samples, and showed clear variations across the industrial area for most of the substances. For some substances, high levels of pollution were found in the soil, sediment and water. Despite this, most measured heavy metals pose no threat environmentally or health-wise due to the very alkaline water in the stream, likely to leave most metals nonbioavailable. Although the stream is heavily loaded with various heavy metals, its lack of finer matter prevents metals from binding to organic ligands, allowing the stream to become more of a transportation means than a place for accumulating metals in the soil and sediments.

  • Bawah, Ayaga
    et al.
    Bawah, Ayaga
    Houle, Brian
    Alam, Nurul
    Razzaque, Abdur
    Streatfield, Peter Kim
    Debpuur, Cornelius
    Welaga, Paul
    Oduro, Abraham
    Hodgson, Abraham
    Tollman, Stephen
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Epidemiology and Global Health. MRC/Wits Rural Public Health Transitions Research Unit (Agincourt), School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa ; INDEPTH Network, Accra, Ghana.
    Collinson, Mark
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Epidemiology and Global Health. MRC/Wits Rural Public Health Transitions Research Unit (Agincourt), School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa ; INDEPTH Network, Accra, Ghana.
    Kahn, Kathleen
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Epidemiology and Global Health. MRC/Wits Rural Public Health Transitions Research Unit (Agincourt), School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa ; INDEPTH Network, Accra, Ghana.
    Toan, Tran Khan
    Phuc, Ho Dang
    Chuc, Nguyen Thi Kim
    Sankoh, Osman
    Clark, Samuel J.
    The Evolving Demographic and Health Transition in Four Low- and Middle-Income Countries: Evidence from Four Sites in the INDEPTH Network of Longitudinal Health and Demographic Surveillance Systems2016In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 11, no 6, e0157281Article in journal (Refereed)
    Abstract [en]

    This paper contributes evidence documenting the continued decline in all-cause mortality and changes in the cause of death distribution over time in four developing country populations in Africa and Asia. We present levels and trends in age-specific mortality (all-cause and cause-specific) from four demographic surveillance sites: Agincourt (South Africa), Navrongo (Ghana) in Africa; Filabavi (Vietnam), Matlab (Bangladesh) in Asia. We model mortality using discrete time event history analysis. This study illustrates how data from INDEPTH Network centers can provide a comparative, longitudinal examination of mortality patterns and the epidemiological transition. Health care systems need to be reconfigured to deal simultaneously with continuing challenges of communicable disease and increasing incidence of non-communicable diseases that require long-term care. In populations with endemic HIV, long-term care of HIV patients on ART will add to the chronic care needs of the community.

  • Sobhani, Hossein
    et al.
    Umeå University, Faculty of Medicine, Department of Odontology.
    Sobhani, Hossein
    Umeå University, Faculty of Medicine, Department of Odontology.
    Rezai, Shahab
    Umeå University, Faculty of Medicine, Department of Odontology.
    Measurement and Comparison of Volumetric Shrinkage of Various Sealers Registered by a Video Imaging Technique Device2016Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Obturation ability of root canal treatment materials are one of the factors that affect the prognosis of root canal treatment with essence of complete closure of the root canal. Cold lateral condensation is one of the most common techniques used for endodontic therapy which sealer acts as sealing and bonding agent between dentin and gutta-percha.

    The aims of the study are to examine and compare the volumetric shrinkage of the three most common endodontic sealers in Sweden categorized by their chemical composition. Our hypothesis is that there is no difference between these sealers regarding shrinkage.

    Epoxy-amine resin based sealer (AH Plus Jet), zinc oxide eugenol based sealer (Tubli-Seal EWT) and calcium hydroxide based (Apexit Plus) have been compared in this study, which are categorized into three major different chemical compositions. A video imaging technique device, AcuVol, has been used to register volumetric shrinkage of these sealers.

    Registration of sealers volumetric shrinkage by AcuVol occurred two times for each sealer during a 48 hr period.

    Mean volumetric shrinkage after 48 hr determined to 6.43 % for epoxy-amine resin based sealer (AH Plus Jet), 6.72 % for zinc oxide eugenol based sealer (Tubli-Seal EWT) and 1.63 % for calcium hydroxide based sealer (Apexit Plus).

    Based on this study, it could not be possible to recommend a sealer in terms of volume shrinkage perspective and determine which sealer is best. There are other parameters of sealer than shrinkage that can affect adequately root canal obturation we should consider.

  • Rezai, Shahab
    et al.
    Umeå University, Faculty of Medicine, Department of Odontology.
    Rezai, Shahab
    Umeå University, Faculty of Medicine, Department of Odontology.
    Sobhani, Hossein
    Umeå University, Faculty of Medicine, Department of Odontology.
    Measurement and Comparison of Volumetric Shrinkage of Various Sealers Registered by a Video Imaging Technique Device2016Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Obturation ability of root canal treatment materials are one of the factors that affect the prognosis of root canal treatment with essence of complete closure of the root canal. Cold lateral condensation is one of the most common techniques used for endodontic therapy which sealer acts as sealing and bonding agent between dentin and gutta-percha.

    The aims of the study are to examine and compare the volumetric shrinkage of the three most common endodontic sealers in Sweden categorized by their chemical composition. Our hypothesis is that there is no difference between these sealers regarding shrinkage.

    Epoxy-amine resin based sealer (AH Plus Jet), zinc oxide eugenol based sealer (Tubli-Seal EWT) and calcium hydroxide based (Apexit Plus) have been compared in this study, which are categorized into three major different chemical compositions. A video imaging technique device, AcuVol, has been used to register volumetric shrinkage of these sealers.

    Registration of sealers volumetric shrinkage by AcuVol occurred two times for each sealer during a 48 hr period.

    Mean volumetric shrinkage after 48 hr determined to 6.43 % for epoxy-amine resin based sealer (AH Plus Jet), 6.72 % for zinc oxide eugenol based sealer (Tubli-Seal EWT) and 1.63 % for calcium hydroxide based sealer (Apexit Plus).

    Based on this study, it could not be possible to recommend a sealer in terms of volume shrinkage perspective and determine which sealer is best. There are other parameters of sealer than shrinkage that can affect adequately root canal obturation we should consider.