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  • Kerwien, Joakim
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Vibrationsdämpare för frontlucka: Koncept för vibrationsdämpare med justering2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Vibration-dampeners for front lid FH/FM

     

    Concepts for vibration-dampers with adjustment

     

    Joakim Kerwien

     

    Abstract

     

    The model-lines FH and FM from Volvo Trucks, have vibration dampers in the front of the cab.  These dampen the front lid and reduces the risk for the front lid to slam into the door. The current vibration damper design is not position adjustable, which is something Volvo wants to have. This makes it easier to adjust the front lid, and get a good gap- and flush-positioning of the front lid, that gives an excellent quality impression for the customer.

    Several concepts are to be developed, which will be compared to each other in a decision matrix.

    The work is carried out at Volvo GTT, the design engineering branch of Volvo GTO in Umeå.

     

    Important delimitations:

    • Development of concepts, no production of parts yet.
    • No strength of materials-calculations or FEM-analysis by me.
    • Use CATIA v5 for CAD-purposes.

     

    Work done:

    Market research has been done, towards rival companies, also researched some former concepts developed by Volvo employees, then I have made some different vibration dampers with adjustability in CATIA v5.

    The concepts developed were then put into a Pugh-matrix, where important attributes and qualities like price, manufacturability, difficulty of assembly were compared with the current damper.

     

    Results of the Pugh-matrix:

    Concepts 2 and 4 were best in this analysis, both got the same amount of points, although this was without any cost analysis involved.

     

    Discussions and Conclusions:

    Two of the concepts are better suited for further development, concepts 2 and 4, both from cost reasons, also they both have adequate adjustability.

    The conclusion is that it is feasible to make different concepts for vibration-dampers with adjustability. The hard part to solve is how you can adjust the dampeners with the front lid closed. 

  • Wänman, Johan
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Orthopaedics.
    Grabowski, Pawel
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Orthopaedics.
    Nyström, Helena
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Geriatric Medicine.
    Gustafsson, Patrik
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Orthopaedics.
    Bergh, Anders
    Umeå University, Faculty of Medicine, Department of Medical Biosciences, Pathology.
    Widmark, Anders
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Oncology.
    Crnalic, Sead
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Orthopaedics.
    Metastatic spinal cord compression as the first sign of malignancy: Outcome after surgery in 69 patients2017In: Acta Orthopaedica, ISSN 1745-3674, E-ISSN 1745-3682, Vol. 88, no 4, 457-462 p.Article in journal (Refereed)
    Abstract [en]

    Background and purpose - Metastatic spinal cord compression (MSCC) as the initial manifestation of malignancy (IMM) limits the time for diagnostic workup; most often, treatment is required before the final primary tumor diagnosis. We evaluated neurological outcome, complications, survival, and the manner of diagnosing the primary tumor in patients who were operated for MSCC as the IMM.

    Patients and methods - Records of 69 consecutive patients (51 men) who underwent surgery for MSCC as the IMM were reviewed. The patients had no history of cancer when they presented with pain (n = 2) and/or neurological symptoms (n = 67).

    Results - The primary tumor was identified in 59 patients. In 10 patients, no specific diagnosis could be established, and they were therefore defined as having cancer of unknown primary tumor (CUP). At the end of the study, 16 patients were still alive (median follow-up 2.5 years). The overall survival time was 20 months. Patients with CUP had the shortest survival (3.5 months) whereas patients with prostate cancer (6 years) and myeloma (5 years) had the longest survival. 20 of the 39 patients who were non-ambulatory preoperatively regained walking ability, and 29 of the 30 ambulatory patients preoperatively retained their walking ability 1 month postoperatively. 15 of the 69 patients suffered from a total of 20 complications within 1 month postoperatively.

    Interpretation - Postoperative survival with MSCC as the IMM depends on the type of primary tumor. Surgery in these patients maintains and improves ambulatory function.

  • Melin, Veronica
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Planeringsarbete inför naturvårdande åtgärder i vattendrag: En jämförelse mellan teoretiska riktlinjer och planering genomförd i praktiken inför åtgärder i Moälven i Örnsköldsviks kommun2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this study was to gain insight into the planning and preparation work at municipal level regarding ecological restoration in river Moälven located in Örnsköldsvik, Sweden. To get the answers I sought, my questions on which this study is based, were how the planning work is done at municipal level regarding restoration in river Moälven in Örnsköldsvik, compared to what is recommended in the theory. I also wondered what factors affected the choice of river Moälven instead of other rivers in the area. Finally, I wanted to know what measurers are supposed to be made, what the area is like today and how the area is supposed to look like after restoration.

    I interviewed Erik Spade who is working with restoration in river Moälven at Örnsköldsvik Municipality. I also had some meetings with Erik where we discussed the restoration work. Erik also provided information via email.

    My result shows that planning in the municipality of Örnsköldsvik generally follows what is stated in the literature. However, there are some differences. The reason Moälven was chosen for the project, was that Moälven is the river in the municipality with the best conditions for continued positive development. In the present project, it is primarily inventories that will be made to get an idea of how the area looks and what actions will be taken in the future. The aim of the project is that Moälvens drainage area should be completely free from unnatural obstacles that prevent fish from getting up in the river.

  • Oja, Katarina
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Kirunas gymnasieelever om den globala uppvärmningen: Vilket intresse och engagemang för den globala uppvärmningen har gymnasieelever i Kiruna?2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Since the beginning of the last century the average surface temperature of the earth has increased about +1°C. Scientists and IPCC, Intergovernmental panel of climate change, agree about the human impact on the climate and the biggest cause is the increased emissions of carbon dioxide. The climate change will affect the whole world. In Sweden, the biggest impact from climate change will be in the northern part of the country, therefore this report focused on Kiruna placed in the north of Sweden. The aim of this study was to get an understanding of high school student engagement, interest and acknowledge about the global warming. A questionnaire was given to the students with 16 questions with the purpose to identify how much they care and have learned about climate change in school, the students in this report will graduate in June 2017. The results from the questionnaire were compared between men and women. Many national studies, like this one, has been done and it was interesting to compare the results with them. This study indicates that the overall knowledge about the climate change is rather low among the students, but many of them wants to learn more about it. 

  • Engström, Jonas
    Umeå University, Faculty of Social Sciences, Umeå School of Business and Economics (USBE), Economics.
    A study of the Marshall-Lerner condition in the least complex economies2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In the aftermath of the financial crisis where global aggregate demand is struggling, countries occasionally get accused of weakening their currency to gain competitiveness. The method of weakening the currency to gain competitiveness is explained by the Marshall-Lerner condition, which states that a devaluation in the long-term will strengthen the balance of trade. But is this policy always rational? And if not, which economies should avoid it? This study investigates whether the structure of the export industry can explain the varying response in the balance of trade from a devaluation.

    The Johansen Procedure with a Vector Error Correction Model is used to estimate long-run price elasticities of demand for exports and imports. The countries chosen are among the 30 countries with the lowest rank of economic complexity based on its output, listed by the Observatory of Economic Complexity. The exports of these countries are consisting of a single or a few goods, which enables for investigating how individual industries respond to a devaluation. The hypothesis is that there are differences between labour- and capital-intensive economies and that the former should respond more positive to a devaluation than the latter.

    The results indicate that there is a pattern, to the opposite of the hypothesis, where the capital-intensive economies respond more positive to a devaluation than the labour-intensive economies. This could be misleading due to underlying factors that should be controlled for to be able to produce reliable estimates. The Marshall-Lerner condition is fulfilled for two countries, Gabon and Niger, out of nine in the final sample.

  • Grundahl, Erika
    Umeå University, Faculty of Science and Technology, Department of Science and Mathematics Education.
    Bilder i läromedel, information eller dekoration?: En läromedelsanalys utifrån ett multimodalt perspektiv med inriktning på läsförståelse.2017Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Den här uppsatsen undersöker hur vida två olika läromedel (”En läsande klass” och Läsförståelse start”) använder sig av text och bildsamspel och ifall detta kan främja elevernas inlärning. Med hjälp av multimodala verktyg såsom ideationell, interpersonell och textuell så undersöks dessa aspekter. Studien undersöker också vilka läsförståelsemöjligheter som dessa läromedel erbjuder. Bägge läromedlen har använt bilder som ett visuellt understöd för att förtydliga textens innehåll. De använder också bilderna för att förmedla detaljer som inte nämns i texten. De läsförståelse möjligheter som läromedlen används sig av är gemensam diskussion i klassen angående texten utifrån fem olika dockor/områden (”En läsande klass”). Det andra läromedlet har använt sig av ett flertal olika texttyper där eleven sedan svara på frågor och påstående utifrån det lästa.

  • Terneborg, Linda
    Umeå University, Faculty of Science and Technology, Department of Science and Mathematics Education.
    Akademiskt välbefinnande och psykologi som kunskapsämne: En kvantitativ studie bland elever som läser psykologi på gymnasienivå2017Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Tidigare forskning har funnit samband mellan akademiskt välbefinnande, school burnout ochupplevda inlärningssvårigheter hos gymnasieelever i bland annat matematik. Denna studieriktades mot ämnet psykologi. Studiens syfte var att öka kunskap om akademisktvälbefinnande, school burnout och upplevda inlärningssvårigheter bland gymnasieelever somläser ämnet psykologi. School burnout undersöktes med School Burnout Inventory (SBI) sommäter känslor av otillräcklighet, cynism och upplevda krav. Upplevda inlärningssvårigheterundersöktes genom en standardiserad enkät som mäter elevens eventuella grad av besvärinom specifika områden av lärande. Urvalet bestod av elever (N=80) från fyra klasser somläste kursen Psykologi 2a. Enkäterna bestod av totalt 14 frågor, en del med nio frågor för SBIoch en del med nio frågor för upplevda inlärningssvårigheter. I motsatts till förväntaderesultat korrelerade school burnout negativt med upplevda inlärningssvårigheter, det vill sägaatt högre nivåer av school burnout visar samband med lägre nivåer av upplevdainlärningssvårigheter. Implikationer av studiens resultat visar att fler studier behövs för attkunna dra slutsatser om psykologiämnets förhållande till akademiskt välbefinnande samt föratt vidare undersöka förhållandet mellan school burnout och upplevda inlärningssvårigheter.

  • Hamberg, Lennart
    Umeå University, Faculty of Science and Technology, Department of Science and Mathematics Education.
    Fysikundervisning med gruppdiskussioner om kontextrika problem2017Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Intresset och motivationen för fysikämnet varierar men är ofta relativt låg bland dagens gymnasieelever. Syftet med denna studie har därför varit att utvärdera en undervisningsmetod som inkluderar gruppdiskussioner om kontextrika problem. De kontextrika problemen förväntas öka elevernas intresse och motivation för fysik. Genom gruppdiskussionerna förväntas eleverna kunna utveckla kommunikationen om fysik och sin förståelse för fysikaliska fenomen. Frågeställningarna i studien är om elevernas motivation för ämnet höjs och om förståelsen för fysikaliska fenomen verkligen ökar med detta undervisningsmoment. I studien fick en klass gymnasieelever på teknikprogrammets första år delta i gruppdiskussioner och problemlösning av kontextrika problem. Intresset och motivationen mättes därefter genom en enkätundersökning och elevernas kunskaper testades genom prov. Resultatet från studien visar tendenser till att intresset och motivationen för fysik ökar. Studiens omfattning är dock inte tillräcklig för att på ett tydligt sätt besvara båda frågeställningarna.

  • Hübsch, Lena
    Umeå University, Faculty of Social Sciences, Department of Geography and Economic History, Economic and social geography.
    Gender equality in County Transportation Plans and potential conflicts with sustainable transportation: A case study from northern Sweden2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    That women and men have different travel patterns has been known for a long time, and previous research argues that gender inequality is the reason for the different travel patterns. Thus, integrating a gender equality perspective into transportation planning has been a relevant topic for quite some time. However, it has been proven to be easier said than done. Gender equality has not been given much attention within transportation planning and planners find it difficult to know how to implement a gender equality perspective. By studying two County Transportation Plans developed by regions in northern Sweden and interviewing infrastructural planners as well as gender equality experts, this thesis will investigate how gender equality is managed and integrated in transport planning on a regional level, and how it could be integrated. How gender equality relates to sustainable transportation on a regional level is another research question. The results show that the planners are aware of women’s and men’s different travel patterns, but they have experienced the difficulties of how gender equality can be integrated in the plans, and integration has previously been made with modesty. This is partly due to lack of competence among the planners and because it has not been prioritized. The result also indicates that gender equality can be beneficial for sustainable transportation, but some goal conflicts were found as well. A conclusion it that there seems to exist a paradox among the respondents where they are unsure of if the transportation should adjust to the current travel needs, or promote change. It is seemingly not either the lack of competence that is the reason gender equality has not been prioritized, but the fact that other areas, such as the need of functional connections due to long distances between places has been seen as more important. The competence and knowledge exists, but need to increase among the planners, and gender equality within transportation planning has to be given more attention on a national level and in the directives from the government. 

  • Meymo, Shivan
    et al.
    Umeå University, Faculty of Social Sciences, Department of Informatics.
    Kenn, Nyström
    Umeå University, Faculty of Social Sciences, Department of Informatics.
    Why do elderly not use socialmedia?: An investigation of the elderly’s attitudes to HCI.2017Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    How do social media and internet usage look like in the eyes of ageing people, specifically

    those at the age of 80 years or above that live independently? What technologies are most

    interesting to them and why? What do they struggle with that could lead them to avoid specific

    technologies or to prefer one technology more than others? The reason of the study was to get

    an insight of elderlies attitudes, regarding technologies in general and social media specifically,

    to know what hinders those seniors to be excluded of the recent technologies and to not be

    plugged into cyberspace. The specific questions that the research wanted to answer were

    “What are the actual barriers for internet use among the elderly?” and “Also, what could be

    done to address these barriers?”. The study was taking place in one retirement house in

    Skellefteå with 4 women at the desired age group and was carried out using semi-structured

    interviews mixed with focus groups as the method for data gathering. This research will be

    assisting an EU funded project aimed to start in the summer of 2017 named PLACE-EE and is

    planned to be a platform for ageing community engagement. The results showed that more

    technical and human support were required in a local environment. The elderly simply did not

    have the drive to personally engage themselves actively in technology to use the internet or

    social media among other things. One of the suggestions made to solve this would be to

    integrate the technology into their daily routines where they are socially active, like the

    community centers that they valued quite a lot.

  • Mejia, Hector
    Umeå University, Faculty of Science and Technology, Umeå Institute of Design.
    Emplant - Designing for a human experience in the  transhumanist era.2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Ludwig Wittgenstein, austrian-born philosopher, wrote that “the limits of my language mean the limits of my world. All I know is what I have words for”. We tend to think so highly of our language because we think so highly about ourselves. Yet imagine be- ing able to communicate emotions without words. Words can’t express the visceral nature of our emotions. Words aren’t enough.

    How can we experience our emotional world, and others, in a more visceral, primitive way?

    This project proposes the creation of a new sense, using embodied technology, to allow human beings to have a different experience of each other’s emotions, through the study of the long distance relationship scenario. In this human augmentation scenario, design, and specially speculative design have an inherent power to create discussion, awareness and bring attention to how the new developed technologies could affect our existence.

    This project is meant to ask questions rather than nd a solution. It is meant for ev- eryone who is ready to think about the future of human beings and our evolution as a species.

    This document presents an overview of the ve (5) months project while detailing the extension of the work and exploration of the product proposed for emotional human augmentation. 

  • Alpay, Aylin
    Umeå University, Faculty of Science and Technology, Umeå Institute of Design.
    Untangling Road Trip Experiences with Conected Car: Planning and bringing it to the car2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    With developing technologies and growing infrastructures, connected experiences are expanding their realms towards various devices and scenarios in our lives. One of the areas, which is going under a big change due to this connectivity is the car related experiences. As connectivity is intrinsically enabler of different experiences and services, it is foreseen that it will bring a different dimension to car and driving related experiences as well.By investigating the future trends and possibilities that connectivity can provide to car and driving related experiences, this thesis aims for imagining the near future scenarios with an explorative approach, focusing on one and addressing to the rising issues with a design proposal that is meaningful to both users and the industry.The result, Tripcloud, contributes to the future scenario of having a road trip with the car, with a new digital platform that aims for supporting the users throughout the planning and bringing the plans into the car experience seamlessly and safely. It aims for reducing today’s existing complexity in terms of interaction and cognition to provide a better experience and avoid driver distraction. With providing organised information pieces, information exchange between people and automated links with mobile devices and car, Tripcloud offers easier an more convenient alternative for road trip planing and bringing the plans into car experiences for the near future.

  • Löf, Anton
    Umeå University, Faculty of Science and Technology, Umeå Institute of Design.
    Generating and Manipulating Sound: Tools for digital music production2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Music making and technological development has always been connected. The digital revolution has made advanced music production, writing and distribution tools universally accessible. New intelligent tools built on machine learning are entering the market potentially changing how we create music and interact with creative content. 

    The aim of this thesis project has been to find alternatives to existing interaction models manifested in modern DAWs (Digital Audio Workstations). Ideas developed through rough sketches and simple prototypes—the outcome consists of three concept videos proposing changes to three moments in the workflow of songwriters and producers.

    This thesis started with an idea of exploring the borderland between computer generated music and human creativity. Through desk research and interviews I learned that computational creativity exist and that there is a lot of different ways of defining creativity and art. Creating creative computers should not aim to replace humans creative abilities—it is rather about automating and creating tools that enhance our creative abilities. 

    To understand how songwriters and producers work the subject were investigated through semi-structured contextual interviews. The different ways of working and using tools were mapped out and potential opportunity areas were identified. This thesis have been a project that through sketching, mock-ups and simple prototypes questions how we use digital tools in music production. These concepts and sketches were continuously brought back to experts for feedback.

    The outcome consists of three concepts. They are presented through three short videos. These videos are now shared with a bigger audience and will act as an conversation starter for people interested in tools for digital music production. 

    1. Automating parts of the songwriting process and create a collaborative workflow between a you and a computer, through a conversational user interface. 

    2. A pressure sensitive touch surface that let you manipulate sound. It is an adaptive system that automatically detects active controls in your DAW—it maps these active controls from your computer screen down to a touch pad. 

    3. The third concept changes the way you organise and look for sound files. It is a automatised process where a software helps you compare different sounds to each other. It takes away most labels and focuses on mapping sound according to its auditory profile.

  • Qian, Yedan
    Umeå University, Faculty of Science and Technology, Umeå Institute of Design. Massachusetts Institute of Technology, Media Laboratory.
    Wonder-LAND: A Tangible Mixed-Reality Book System For Explorative Learning in Science2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Every child is born a scientist, with curiosity to explore the environment through experimentation. However, in practice, science education still very focuses on transmitting facts instead of encouraging personal exploration. Conducting science exploration in a classroom can be complicated for kids and limited by safety, money and laboratory infrastructure. But what if we could create a middle ground between science and fiction, a world where kids discover and experiment in ways that could be impossible in real life but still true to science? This project is to design an imaginative and accessible tool to help kids develop a scientific mindset and practice through play.

    Wonder-LAND is a mixed reality book system that empowers kids to discover the unseen and experiment the impossible through play. The system combines AR and VR technology with various traditional paper-based mechanisms from pop-up book, cut-out toys and movable cards to bring a world alive. In such way, kids can interact with the tangible material, paper, to unlock amazing 3D virtual phenomena. They can discover things that are not visible to the naked eyes through metaphorical paper tools. And they can also conduct experiments that are impossible in reality by creating their own universe and controlling parameters in simulation. And those playful interactions spark their curiosity and passion for more scientific exploration.

  • Perez-Cornago, Aurora
    et al.
    Appleby, Paul N.
    Pischon, Tobias
    Tsilidis, Konstantinos K.
    Tjonneland, Anne
    Olsen, Anja
    Overvad, Kim
    Kaaks, Rudolf
    Kuehn, Tilman
    Boeing, Heiner
    Steffen, Annika
    Trichopoulou, Antonia
    Lagiou, Pagona
    Kritikou, Maria
    Krogh, Vittorio
    Palli, Domenico
    Sacerdote, Carlotta
    Tumino, Rosario
    Bueno-de-Mesquita, H. Bas
    Agudo, Antonio
    Larranaga, Nerea
    Molina-Portillo, Elena
    Barricarte, Aurelio
    Chirlaque, Maria-Dolores
    Ramon Quiros, J.
    Stattin, Pär
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Urology and Andrology. Department of Surgical Sciences, Uppsala University.
    Häggström, Christel
    Umeå University, Faculty of Medicine, Department of Biobank Research. Department of Surgical Sciences, Uppsala University.
    Wareham, Nick
    Khaw, Kay-Tee
    Schmidt, Julie A.
    Gunter, Marc
    Freisling, Heinz
    Aune, Dagfinn
    Ward, Heather
    Riboli, Elio
    Key, Timothy J.
    Travis, Ruth C.
    Tall height and obesity are associated with an increased risk of aggressive prostate cancer: results from the EPIC cohort study2017In: BMC Medicine, ISSN 1741-7015, E-ISSN 1741-7015, Vol. 15, 115Article in journal (Refereed)
    Abstract [en]

    Background: The relationship between body size and prostate cancer risk, and in particular risk by tumour characteristics, is not clear because most studies have not differentiated between high-grade or advanced stage tumours, but rather have assessed risk with a combined category of aggressive disease. We investigated the association of height and adiposity with incidence of and death from prostate cancer in 141,896 men in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. Methods: Multivariable-adjusted Cox proportional hazards models were used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs). After an average of 13.9 years of follow-up, there were 7024 incident prostate cancers and 934 prostate cancer deaths. Results: Height was not associated with total prostate cancer risk. Subgroup analyses showed heterogeneity in the association with height by tumour grade (P-heterogeneity = 0.002), with a positive association with risk for high-grade but not low-intermediate-grade disease (HR for high-grade disease tallest versus shortest fifth of height, 1.54; 95% CI, 1.18-2.03). Greater height was also associated with a higher risk for prostate cancer death (HR = 1.43, 1.14-1.80). Body mass index (BMI) was significantly inversely associated with total prostate cancer, but there was evidence of heterogeneity by tumour grade (P-heterogeneity = 0.01; HR = 0.89, 0.79-0.99 for low-intermediate grade and HR = 1.32, 1.01-1.72 for high-grade prostate cancer) and stage (P-heterogeneity = 0.01; HR = 0.86, 0.75-0.99 for localised stage and HR = 1.11, 0.92-1.33 for advanced stage). BMI was positively associated with prostate cancer death (HR = 1.35, 1.09-1.68). The results for waist circumference were generally similar to those for BMI, but the associations were slightly stronger for high-grade (HR = 1.43, 1.07-1.92) and fatal prostate cancer (HR = 1.55, 1.23-1.96). Conclusions: The findings from this large prospective study show that men who are taller and who have greater adiposity have an elevated risk of high-grade prostate cancer and prostate cancer death.

  • Willems, Sara M.
    et al.
    Wright, Daniel J.
    Day, Felix R.
    Trajanoska, Katerina
    Joshi, Peter K.
    Morris, John A.
    Matteini, Amy M.
    Garton, Fleur C.
    Grarup, Niels
    Oskolkov, Nikolay
    Thalamuthu, Anbupalam
    Mangino, Massimo
    Liu, Jun
    Demirkan, Ayse
    Lek, Monkol
    Xu, Liwen
    Wang, Guan
    Oldmeadow, Christopher
    Gaulton, Kyle J.
    Lotta, Luca A.
    Miyamoto-Mikami, Eri
    Rivas, Manuel A.
    White, Tom
    Loh, Po-Ru
    Aadahl, Mette
    Amin, Najaf
    Attia, John R.
    Austin, Krista
    Benyamin, Beben
    Brage, Soren
    Cheng, Yu-Ching
    Cieszczyk, Pawel
    Derave, Wim
    Eriksson, Karl-Fredrik
    Eynon, Nir
    Linneberg, Allan
    Lucia, Alejandro
    Massidda, Myosotis
    Mitchell, Braxton D.
    Miyachi, Motohiko
    Murakami, Haruka
    Padmanabhan, Sandosh
    Pandey, Ashutosh
    Papadimitriou, Loannis
    Rajpal, Deepak K.
    Sale, Craig
    Schnurr, Theresia M.
    Sessa, Francesco
    Shrine, Nick
    Tobin, Martin D.
    Varley, Ian
    Wain, Louise V.
    Wray, Naomi R.
    Lindgren, Cecilia M.
    MacArthur, Daniel G.
    Waterworth, Dawn M.
    McCarthy, Mark I.
    Pedersen, Oluf
    Khaw, Kay-Tee
    Kie, Douglas P.
    Pitsiladis, Yannis
    Fuku, Noriyuki
    Franks, Paul W.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine. Umeå University, Faculty of Medicine, Department of Biobank Research. Genetic and Molecular Epidemiology Unit, Department of Clinical Sciences, Lund University, Skånes University Hospital, 222 41 Lund, Sweden.
    North, Kathryn N.
    van Duijn, Cornelia M.
    Mather, Karen A.
    Hansen, Torben
    Hansson, Ola
    Spector, Tim
    Murabito, Joanne M.
    Richards, J. Brent
    Rivadeneira, Fernando
    Langenberg, Claudia
    Perry, John R. B.
    Wareham, Nick J.
    Scott, Robert A.
    Large-scale GWAS identifies multiple loci for hand grip strength providing biological insights into muscular fitness2017In: Nature Communications, ISSN 2041-1723, E-ISSN 2041-1723, Vol. 8, 16015Article in journal (Refereed)
    Abstract [en]

    Hand grip strength is a widely used proxy of muscular fitness, a marker of frailty, and predictor of a range of morbidities and all-cause mortality. To investigate the genetic determinants of variation in grip strength, we perform a large-scale genetic discovery analysis in a combined sample of 195,180 individuals and identify 16 loci associated with grip strength (P<5 x 10(-8)) in combined analyses. A number of these loci contain genes implicated in structure and function of skeletal muscle fibres (ACTG1), neuronal maintenance and signal transduction (PEX14, TGFA, SYT1), or monogenic syndromes with involvement of psychomotor impairment (PEX14, LRPPRC and KANSL1). Mendelian randomization analyses are consistent with a causal effect of higher genetically predicted grip strength on lower fracture risk. In conclusion, our findings provide new biological insight into the mechanistic underpinnings of grip strength and the causal role of muscular strength in age-related morbidities and mortality.

  • Rivas, D. E.
    et al.
    Borot, A.
    Cardenas, D. E.
    Marcus, G.
    Gu, X.
    Herrmann, D.
    Xu, J.
    Tan, J.
    Kormin, D.
    Ma, G.
    Dallari, W.
    Tsakiris, G. D.
    Foldes, I. B.
    Chou, S. -w.
    Weidman, M.
    Bergues, B.
    Wittmann, T.
    Schroeder, H.
    Tzallas, P.
    Charalambidis, D.
    Razskazovskaya, O.
    Pervak, V.
    Krausz, F.
    Veisz, László
    Umeå University, Faculty of Science and Technology, Department of Physics. Max-Planck-Institut für Quantenoptik, Garching, Germany.
    Next Generation Driver for Attosecond and Laser-plasma Physics2017In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 7, 5224Article in journal (Refereed)
    Abstract [en]

    The observation and manipulation of electron dynamics in matter call for attosecond light pulses, routinely available from high-order harmonic generation driven by few-femtosecond lasers. However, the energy limitation of these lasers supports only weak sources and correspondingly linear attosecond studies. Here we report on an optical parametric synthesizer designed for nonlinear attosecond optics and relativistic laser-plasma physics. This synthesizer uniquely combines ultra-relativistic focused intensities of about 10(20)W/cm(2) with a pulse duration of sub-two carrier-wave cycles. The coherent combination of two sequentially amplified and complementary spectral ranges yields sub-5-fs pulses with multi-TW peak power. The application of this source allows the generation of a broad spectral continuum at 100-eV photon energy in gases as well as high-order harmonics in relativistic plasmas. Unprecedented spatio-temporal confinement of light now permits the investigation of electric-field-driven electron phenomena in the relativistic regime and ultimately the rise of next-generation intense isolated attosecond sources.

  • van Teeseling, Muriel C. F.
    et al.
    Umeå University, Faculty of Medicine, Molecular Infection Medicine Sweden (MIMS). Umeå University, Faculty of Medicine, Department of Molecular Biology (Faculty of Medicine). Umeå University, Faculty of Medicine, Umeå Centre for Microbial Research (UCMR).
    de Pedro, Miguel A.
    Cava, Felipe
    Umeå University, Faculty of Medicine, Molecular Infection Medicine Sweden (MIMS). Umeå University, Faculty of Medicine, Department of Molecular Biology (Faculty of Medicine). Umeå University, Faculty of Medicine, Umeå Centre for Microbial Research (UCMR).
    Determinants of Bacterial Morphology: From Fundamentals to Possibilities for Antimicrobial Targeting2017In: Frontiers in Microbiology, ISSN 1664-302X, E-ISSN 1664-302X, Vol. 8, 1264Article in journal (Refereed)
    Abstract [en]

    Bacterial morphology is extremely diverse. Specific shapes are the consequence of adaptive pressures optimizing bacterial fitness. Shape affects critical biological functions, including nutrient acquisition, motility, dispersion, stress resistance and interactions with other organisms. Although the characteristic shape of a bacterial species remains unchanged for vast numbers of generations, periodical variations occur throughout the cell (division) and life cycles, and these variations can be influenced by environmental conditions. Bacterial morphology is ultimately dictated by the net-like peptidoglycan (PG) sacculus. The species-specific shape of the PG sacculus at any time in the cell cycle is the product of multiple determinants. Some morphological determinants act as a cytoskeleton to guide biosynthetic complexes spatiotemporally, whereas others modify the PG sacculus after biosynthesis. Accumulating evidence supports critical roles of morphogenetic processes in bacteria-host interactions, including pathogenesis. Here, we review the molecular determinants underlying morphology, discuss the evidence linking bacterial morphology to niche adaptation and pathogenesis, and examine the potential of morphological determinants as antimicrobial targets.

  • Aguilo, Francesca
    et al.
    Umeå University, Faculty of Medicine, Department of Medical Biosciences. Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA.
    Zakirova, Zuchra
    Nolan, Katie
    Wagner, Ryan
    Sharma, Rajal
    Hogan, Megan
    Wei, Chengguo
    Sun, Yifei
    Walsh, Martin J.
    Kelley, Kevin
    Zhang, Weijia
    Ozelius, Laurie J.
    Gonzalez-Alegre, Pedro
    Zwaka, Thomas P.
    Ehrlich, Michelle E.
    THAP1: Role in Mouse Embryonic Stem Cell Survival and Differentiation2017In: Stem Cell Reports, ISSN 2213-6711, Vol. 9, no 1, 92-107 p.Article in journal (Refereed)
    Abstract [en]

    THAP1 (THAP [Thanatos-associated protein] domain-containing, apoptosis-associated protein 1) is a ubiquitously expressed member of a family of transcription factors with highly conserved DNA-binding and protein-interacting regions. Mutations in THAP1 cause dystonia, DYT6, a neurologic movement disorder. THAP1 downstream targets and the mechanism via which it causes dystonia are largely unknown. Here, we show that wild-type THAP1 regulates embryonic stem cell (ESC) potential, survival, and proliferation. Our findings identify THAP1 as an essential factor underlying mouse ESC survival and to some extent, differentiation, particularly neuroectodermal. Loss of THAP1 or replacement with a disease-causing mutation results in an enhanced rate of cell death, prolongs Nanog, Prdm14, and/or Rex1 expression upon differentiation, and results in failure to upregulate ectodermal genes. ChIP-Seq reveals that these activities are likely due in part to indirect regulation of gene expression.

  • Strinnholm, Åsa
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Occupational and Environmental Medicine. Umeå University, Faculty of Medicine, Department of Nursing.
    Hedman, Linnea
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Occupational and Environmental Medicine. Division of Nursing, Department of Health Sciences, Luleå University of Technology.
    Winberg, Anna
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Jansson, Sven-Arne
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Occupational and Environmental Medicine.
    Lindh, Viveca
    Umeå University, Faculty of Medicine, Department of Nursing.
    Rönmark, Eva
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Occupational and Environmental Medicine.
    Health Related Quality of Life among schoolchildren aged 12-13 years in relation to food hypersensitivity phenotypes: a population-based study2017In: Clinical and Translational Allergy, ISSN 2045-7022, E-ISSN 2045-7022, Vol. 7, 20Article in journal (Refereed)
    Abstract [en]

    Background: While Health Related Quality of Life has been investigated among children with IgE-mediated food allergy, less is known about quality of life among children with other types of hypersensitivity to food. The aim of this study was to investigate Health Related Quality of Life (HRQL) in children with and without food hypersensitivity. Further, we compared HRQL between children with different phenotypes of food hypersensitivity. Methods: In a large population-based cohort of schoolchildren in Northern Sweden, the parents of 2612 (96% of invited) completed a questionnaire. All 125 (5%) children who reported complete elimination of milk, egg, fish or wheat due to food hypersensitivity were invited to a clinical examination and 94 children participated. Of these, 75 children also completed a generic (KIDSCREEN-52) and a disease-specific HRQL questionnaire (FAQLQ-TF). Thereafter, these children were categorised into the different phenotypes: current food allergy, outgrown food allergy, and lactose intolerance. Additionally, 209 children with unrestricted diets answered the generic questionnaire. Results: The median score of all KIDSCREEN-52 domains were above the population norm of 50 both in children with and without food hypersensitivity. No significant differences in distribution in generic or disease-specific HRQL were found between children with or without food hypersensitivity. There were no significant differences in HRQL between children with different phenotypes of food hypersensitivity. However, children with current food allergy tended to have the lowest HRQL. Further, poor HRQL defined as >= 75th percentile for the disease specific score was significantly more common in the current food allergy phenotype in the domain Emotional impact and the total FAQLQ, compared to the other phenotypes. Conclusions: In this population-based study, 12-13 year old children reported good HRQL regardless of having food hypersensitivity or not. However, the children with the current phenotype reported lower HRQL than the other phenotypes.

  • Lundell, Sara
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Tistad, Malin
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy. School of Education, Health and Social Studies, Dalarna University.
    Rehn, Börje
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Wiklund, Maria
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Holmner, Åsa
    Umeå University, Faculty of Medicine, Department of Radiation Sciences.
    Wadell, Karin
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Building COPD care on shaky ground: a mixed methods study from Swedish primary care professional perspective2017In: BMC Health Services Research, ISSN 1472-6963, E-ISSN 1472-6963, Vol. 17, 467Article in journal (Refereed)
    Abstract [en]

    Background: Chronic obstructive pulmonary disease (COPD) is a public health problem. Interprofessional collaboration and health promotion interventions such as exercise training, education, and behaviour change are cost effective, have a good effect on health status, and are recommended in COPD treatment guidelines. There is a gap between the guidelines and the healthcare available to people with COPD. The aim of this study was to increase the understanding of what shapes the provision of primary care services to people with COPD and what healthcare is offered to them from the perspective of healthcare professionals and managers. Methods: The study was conducted in primary care in a Swedish county council during January to June 2015. A qualitatively driven mixed methods design was applied. Qualitative and quantitative findings were merged into a joint analysis. Interviews for the qualitative component were performed with healthcare professionals (n = 14) from two primary care centres and analysed with qualitative content analysis. Two questionnaires were used for the quantitative component; one was answered by senior managers or COPD nurses at primary care centres (n = 26) in the county council and the other was answered by healthcare professionals (n = 18) at two primary care centres. The questionnaire data were analysed with descriptive statistics. Results: The analysis gave rise to the overarching theme building COPD care on shaky ground. This represents professionals driven to build a supportive COPD care on 'shaky' organisational ground in a fragmented and non-compliant healthcare organisation. The shaky ground is further represented by uninformed patients with a complex disease, which is surrounded with shame. The professionals are autonomous and pragmatic, used to taking responsibility for their work, and with limited involvement of the management. They wish to provide high quality COPD care with interprofessional collaboration, but they lack competence and are hindered by inadequate routines and lack of resources. Conclusions: There is a gap between COPD treatment guidelines and the healthcare that is provided in primary care. To facilitate implementation of the guidelines several actions are needed, such as further training for professionals, additional resources, and improved organisational structure for interprofessional collaboration and patient education.

  • Borg, Farhana
    Umeå University, Faculty of Social Sciences, Department of applied educational science. School of Education, Health and Social Studies, Dalarna University, SE-791 88 Falun, Sweden.
    Kids, cash and sustainability: Economic knowledge and behaviors among preschool children2017In: Cogent Education, ISSN 2331-186X, Vol. 4, no 1, 1349562Article in journal (Refereed)
    Abstract [en]

    Although young children are often involved in economic transactions of various kinds in their daily activities, research on their knowledge and behaviors in relation to sustainable economics is limited. Sustainable economics deals with, among others, equity, corporate responsibility and poverty reduction. This study explored preschool children's knowledge and behaviors concerning the use of money, their willingness to share resources with friends and the sources of knowledge about economic issues. A total of 53 final-year preschool children, aged five to six, from 12 preschools in Sweden were interviewed. The data were analyzed using content analysis and the Structure of the Observed Learning Outcomes (SOLO) Taxonomy. The results show that the children considered money to be used largely for the consumption of goods, while a few wanted to donate their money to the poor and to family members. With regards to sharing resources, most of the children wanted to share their candies with friends, and they viewed sharing as being a social responsibility or a moral obligation, or as being fair. Parents, teachers and the children themselves were reported as the main sources of knowledge. Further research is needed to enhance our knowledge about how to integrate economic sustainability issues in preschool.

  • Burström, Lage
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Occupational and Environmental Medicine.
    Aminoff, Anna
    Björ, Bodil
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Occupational and Environmental Medicine.
    Manttari, Sate
    Nilsson, Tohr
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Occupational and Environmental Medicine.
    Pettersson, Hans
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Occupational and Environmental Medicine.
    Rintamaki, Hannu
    Rodin, Ingemar
    Shilov, Victor
    Talykomv, Ljudmila
    Vaktskjold, Arild
    Wahlström, Jens
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Occupational and Environmental Medicine.
    Musculoskeletal symptoms and exposure to whole-body vibration among open-pit mine workers in the arctic2017In: International Journal of Occupational Medicine and Environmental Health, ISSN 1232-1087, E-ISSN 1896-494X, Vol. 30, no 4, 553-564 p.Article in journal (Refereed)
    Abstract [en]

    Objectives: This cross-sectional questionnaire study was carried out at 4 open-pit mines in Finland, Norway, Russia and Sweden as part of the MineHealth project. The aim has been to compare the prevalence of musculoskeletal symptoms between drivers of mining vehicles and non-drivers. Material and Methods: The mine workers were asked whether they had suffered from any musculoskeletal symptoms during the previous 12 months in specified body regions, and to grade the severity of these symptoms during the past month. They were also asked about their daily driving of mining vehicles. Results: The questionnaire was completed by 1323 workers (757 vehicle drivers) and the reported prevalence and severity of symptoms were highest for the lower back, followed by pain in the neck, shoulder and upper back. Drivers in the Nordic mines reported fewer symptoms than non-drivers, while for Russian mine workers the results were the opposite of that. The daily driving of mining vehicles had no significant association with the risk of symptoms. Female drivers indicated a higher prevalence of symptoms as compared to male drivers. Conclusions: The study provided only weak support for the hypothesis that drivers of vehicles reported a higher prevalence of musculoskeletal symptoms than non-vehicle drivers. There were marked differences in the prevalence of symptoms among workers in various enterprises, even though the nature of the job tasks was similar.

  • Eliasson, Kent
    et al.
    Umeå University, Faculty of Social Sciences, Umeå School of Business and Economics (USBE), Economics. Growth Analysis, Studentplan 3, 831 40 Östersund, Sweden.
    Hansson, Pär
    Lindvert, Markus
    Effects of foreign acquisitions on R&D and high-skill activities2017In: Small Business Economics, ISSN 0921-898X, E-ISSN 1573-0913, Vol. 49, no 1, 163-187 p.Article in journal (Refereed)
    Abstract [en]

    Using Swedish microdata, we find no evidence for the concerns circulating in the public debate that foreign acquisitions lead to reductions in both R&D expenditures and high-skilled activities in targeted domestic firms for either MNEs or non-MNEs. Previous studies have only focused on larger firms. In this paper, we are able to study the impact on smaller firms (fewer than 50 employees), which is important because 90% of the firms acquired by foreign enterprises meet this criterion. For this group of firms, there is no information on R&D, but by using the register of educational attainment, we obtain data on the share of high-skilled labour in all Swedish firms, irrespective of size. Interestingly, we find that among smaller firms, foreign enterprises tend to acquire high-productive, skill-intensive firms (cherry-picking). After the acquisitions, skill upgrading appears in acquired smaller, non-MNE firms, particularly in the service sector.

  • Lundqvist, Anette
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Family Medicine.
    Sandström, Herbert
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Family Medicine.
    Bäckström, Torbjörn
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Obstetrics and Gynecology.
    The relationship between weight gain during pregnancy and allopregnanolone levels: a longitudinal study2017In: Endocrine Connections, ISSN 2049-3614, E-ISSN 2049-3614, Vol. 6, no 4, 253-259 p.Article in journal (Refereed)
    Abstract [en]

    Objective: Large weight gain during pregnancy is a risk factor for complications for mother and fetus. Hunger and satiety are regulated in the hypothalamus, where the gamma-amino-butyric acid system (GABA) has an important role. Allopregnanolone, a progesterone metabolite, increases during pregnancy and is a potent GABA-A receptor modulating steroid. Allopregnanolone has been shown to induce overeating in rodents. The aim was to investigate whether there is a relationship between weight gain and allopregnanolone concentrations during pregnancy in humans. Design: A longitudinal, cohort study. Methods: Pregnant women (n = 56) were recruited in primary care in northern Sweden. Allopregnanolone concentrations in plasma were measured using radioimmunoassay and weight was measured in gestational weeks 12 and 35. Results: Weight increase correlated significantly to allopregnanolone in late pregnancy increase (r(s) = 0.320; P = 0.016), indicating a positive relationship between weight increase and allopregnanolone increase. A positive relationship was also noted between allopregnanolone in the 35th gestational week and weight increase. Women who gained = 11 kg during pregnancy showed higher allopregnanolone concentrations in week 35 and higher increase compared to women who increased < 11 kg (P = 0.006 and P = 0.009 resp.). There was no difference in weight or allopregnanolone concentrations at the onset of pregnancy. Conclusions: The results show a relationship between weight gain during pregnancy and increase in allopregnanolone concentrations.

  • Sjöström, Olle
    et al.
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Oncology.
    Lindholm, Lars
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Epidemiology and Global Health.
    Melin, Beatrice
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Oncology.
    Colonoscopic surveillance - a cost-effective method to prevent hereditary and familial colorectal cancer2017In: Scandinavian Journal of Gastroenterology, ISSN 0036-5521, E-ISSN 1502-7708, Vol. 52, no 9, 1002-1007 p.Article in journal (Refereed)
    Abstract [en]

    Objective: Approximately 20-30% of all colorectal cancer (CRC) cases may have a familial contribution. The family history of CRC can be prominent (e.g., hereditary colorectal cancer (HCRC)) or more moderate (e.g., familial colorectal cancer (FCRC)). For family members at risk, colonoscopic surveillance is a well-established method to prevent both HCRC and FCRC, although the evidence for the exact procedures of the surveillance is limited. Surveillance can come at a high price if individuals are frequently examined, as this may result in unnecessary colonoscopies in relation to actual risk for CRC. This study analyses the cost-effectiveness of a surveillance programme implemented in the Northern Sweden Health Care Region.

    Methods: The study includes 259 individuals prospectively recorded in the colonoscopic surveillance programme registry at the Cancer Prevention Clinic, Umea University Hospital. We performed a cost-utility analysis with a contrafactual design: we compared observed costs and loss of quality-adjusted life years (QALYs) due to CRC with the surveillance programme to an expected outcome without surveillance. The main measure was the incremental cost-effectiveness ratio (ICER) between surveillance and non-surveillance. Scenario analysis was used to explore uncertainty.

    Results: The ICER between surveillance and non-surveillance in the base model was 3596Euro/QALY. The ICER varied from -4620Euro in the best-case scenario to 33,779Euro in the worst-case scenario.

    Conclusion: Colonoscopic surveillance is a very cost-effective method to prevent HCRC and FCRC compared to current thresholds for cost-effectiveness and other cancer preventive interventions.

  • Berglund, André
    Umeå University, Faculty of Science and Technology, Department of Mathematics and Mathematical Statistics.
    Numerical Simulations of Linear Stochastic Oscillators: driven by Wiener and Poisson processes2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The main component of this essay is the numerical analysis of stochastic differential equations driven by Wiener and Poisson processes. In order to do this, we focus on two model problems, the geometric Brownian motion and the linear stochastic oscillator, studied in the literature for stochastic differential equations only driven by a Wiener process. This essay covers theoretical as well as numerical investigations of jump - or more specifically, Poisson - processes and how they influence the above model problems.

  • Norling, Malin
    et al.
    Umeå University, Faculty of Science and Technology, Department of Mathematics and Mathematical Statistics.
    Hjulfors, Sofia
    Umeå University, Faculty of Science and Technology, Department of Mathematics and Mathematical Statistics.
    Bidding strategies in the Swedish housing market2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report focuses on an introduction of game theoretical models and how they can be applied in the Swedish housing market. Game theory is a study of mathematical models of human conflicts and cooperation between rational decision makers within a competitive situation. There are several different strategies that a player can use. In this thesis each strategy is assigned to one player. So how will the players behave in a game, and what strategy is the most successful? By using the software MatLab, the authors creates a game where the strategies assigned to each player gets randomly distributed budgets and are randomly selected to place bids during the game. The game is then played 1 000 000 times to see what strategy is the most successful. It is also tested to see what strategy is the most successful if the players have the same budgets. The authors conclude that in practice it is the size of the budget that determines who will win the bidding, hence there are minor differences between the different strategies in how much they pay on average to win.

  • Olsson, Christoffer
    Umeå University, Faculty of Science and Technology, Department of Mathematics and Mathematical Statistics.
    Discreet Discrete Mathematics: Secret Communication Using Latin Squares and Quasigroups2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis describes methods of secret communication based on latin squares and their close relative, quasigroups. Different types of cryptosystems are described, including ciphers, public-key cryptosystems, and cryptographic hash functions. There is also a chapter devoted to different secret sharing schemes based on latin squares. The primary objective is to present previously described cryptosystems and secret sharing schemes in a more accessible manner, but this text also defines two new ciphers based on isotopic latin squares and reconstructs a lost proof related to row-latin squares.

  • Segersson, David
    et al.
    Eneroth, Kristina
    Gidhagen, Lars
    Johansson, Christer
    Omstedt, Gunnar
    Engström Nylén, Anders
    Forsberg, Bertil
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Occupational and Environmental Medicine.
    Health Impact of PM10, PM2.5 and Black Carbon Exposure Due to Different Source Sectors in Stockholm, Gothenburg and Umea, Sweden2017In: International Journal of Environmental Research and Public Health, ISSN 1661-7827, E-ISSN 1660-4601, Vol. 14, no 7, 742Article in journal (Refereed)
    Abstract [en]

    The most important anthropogenic sources of primary particulate matter (PM) in ambient air in Europe are exhaust and non-exhaust emissions from road traffic and combustion of solid biomass. There is convincing evidence that PM, almost regardless of source, has detrimental health effects. An important issue in health impact assessments is what metric, indicator and exposure-response function to use for different types of PM. The aim of this study is to describe sectorial contributions to PM exposure and related premature mortality for three Swedish cities: Gothenburg, Stockholm and Umea. Exposure is calculated with high spatial resolution using atmospheric dispersion models. Attributed premature mortality is calculated separately for the main local sources and the contribution from long-range transport (LRT), applying different relative risks. In general, the main part of the exposure is due to LRT, while for black carbon, the local sources are equally or more important. The major part of the premature deaths is in our assessment related to local emissions, with road traffic and residential wood combustion having the largest impact. This emphasizes the importance to resolve within-city concentration gradients when assessing exposure. It also implies that control actions on local PM emissions have a strong potential in abatement strategies.

  • Åström, Christofer
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Occupational and Environmental Medicine.
    Åström, Daniel Oudin
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Occupational and Environmental Medicine. Department of Clinical Sciences, Malmö, Lund University, Jan Waldenströms gata 35, SE 21428 Malmö, Sweden.
    Andersson, Camilla
    Ebi, Kristie L
    Forsberg, Bertil
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Occupational and Environmental Medicine.
    Vulnerability Reduction Needed to Maintain Current Burdens of Heat-Related Mortality in a Changing Climate-Magnitude and Determinants2017In: International Journal of Environmental Research and Public Health, ISSN 1661-7827, E-ISSN 1660-4601, Vol. 14, no 7, 741Article in journal (Refereed)
    Abstract [en]

    The health burden from heatwaves is expected to increase with rising global mean temperatures and more extreme heat events over the coming decades. Health-related effects from extreme heat are more common in elderly populations. The population of Europe is rapidly aging, which will increase the health effects of future temperatures. In this study, we estimate the magnitude of adaptation needed to lower vulnerability to heat in order to prevent an increase in heat-related deaths in the 2050s; this is the Adaptive Risk Reduction (ARR) needed. Temperature projections under Representative Concentration Pathway (RCP) 4.5 and RCP 8.5 from 18 climate models were coupled with gridded population data and exposure-response relationships from a European multi-city study on heat-related mortality. In the 2050s, the ARR for the general population is 53.5%, based on temperature projections under RCP 4.5. For the population above 65 years in Southern Europe, the ARR is projected to be 45.9% in a future with an unchanged climate and 74.7% with climate change under RCP 4.5. The ARRs were higher under RCP 8.5. Whichever emission scenario is followed or population projection assumed, Europe will need to adapt to a great degree to maintain heat-related mortality at present levels, which are themselves unacceptably high, posing an even greater challenge.

  • Näslund, Simon
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Stålhall: Dimensionering av en bärande stålstomme till en hallbyggnad2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The work involved in the design of aload-bearing steel framework of a hall building is an extensive process. The purpose of the project isto design the load-bearing steel framework of a hall building and compare the steel’s characteristics with wood ́s characteristics. The objective is to gather information about steel and wood, then compare the materials similarities and differences. Furthermore, with the help of calculating programs FEM-design and Concrete sections, to design a bearing steel framework to a hall building.From the results of the two calculating programs a 3D model will be drawn in the CAD-program Tekla Structures.The results of this project showthe maximum forces required to designthe concretebase plateas well asthemost utilized building componentineach category. Steel and wood are two quite different materials based on the aspects of: material characteristics, moisture, fire and environment. This makes it hard to make a fair comparison in order to find the better or worst between the materials. For example; it is sometimes easy to say that wood is the better material from an environmental perspective, because it has a lower energy consumption and less dangerous emissions in the manufacturing phase than steel. Looking at it with a wider perspective, the choice between the materials may be different and more interesting. Aspects such as volume increase, flexibility and life span can be included in the calculations; and the material’s energy consumption over a year could be considered instead of only the energy consumption during manufacture.

  • Nygren, Fanny
    Umeå University, Faculty of Social Sciences, Department of Food and Nutrition.
    Kost vid graviditet: en studie om kostvanor och informationskällor gällande kostråd.2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Bakgrund Dåliga kostvanor hos den blivande mamman kanleda till kostrelaterade sjukdomar hos mamman samt fostret. Det är viktigt att ta reda på hur kvinnors kostvanor ser ut och hur väl de informationskällor till kost som finns tillgängliga, används av de gravida.

    Syfte Att undersöka kvinnors kostvanor och informationskällor gällande kost under graviditet. 

    Metod En webbaserad enkät innehållande 13 frågor distribuerades över internetbaserade hemsidor: Facebook, familjeliv.se och minbebis.se. Totalt deltog 211, respondenterna var gravida i minst fjärde månaden eller hade fött barn under de senaste fem åren. För att analysera datan användes icke-parametriska tester (Mann Whitney U-test, Chi-2 och Kruskal Wallis H-test).

    Resultat Medelålder på respondenterna var 31 år (sd 5) och 85 % uppgav att de hade barn sedan tidigare medan resterande av kvinnorna var gravida (13 av de gravida hade även barn sedan tidigare). Den mest frekvent använda informationskällan gällande kostråd var Livsmedelsverket.  Majoriteten (92%) av respondenterna ändrade inte sina matvanor under graviditeten. Ett ökat intag av grönsaker, frukt och fisk under graviditeten var en del av de förändringar som kvinnor genomförde. Relativt många av respondenterna uppgav att de konsumerat något eller några av de livsmedel som bör ätas med försiktighet under graviditet.

    Slutsats Baserat på kvinnornas kostintag innan graviditet skulle en kostförändring ha varit gynnsam. Dock ändrade endast 8 % av respondenterna sina matvanor under graviditeten. En relativt stor andel konsumerade också livsmedel som bör ätas med försiktighet under graviditet. Resultaten talar för att en större informationsspridning omkostvanor till blivande föräldrar är motiverat, för att minska risken för komplikationer hos mamman och fostret.

  • Forslund, Isak
    et al.
    Umeå University, Faculty of Social Sciences, Umeå School of Business and Economics (USBE), Statistics.
    Öberg, Magnus
    Umeå University, Faculty of Social Sciences, Umeå School of Business and Economics (USBE), Statistics.
    JÄMFÖRELSE AV KLASSIFICERINGSMETODER PÅ DATA FRÅN BETULA-STUDIEN: En jämförande studie mellan Linjär Diskriminantanalys, Gradient Tree Boosting och Support Vector Machines2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Det saknas idag resultat inom forskning som kan urskilja en klassificeringsmetod som konsekvent presterar bättre än övriga, vilken metod som presterar bäst beror mer på datats karaktäristika än själva metoden. Samtidigt är klassificering ett viktigt och användbart verktyg som används inom flera områden, bland annat medicin där klassificeringsmetoder används i stor utsträckning och resultaten av klassificering kan vara livsavgörande. Det har i tidigare studier visats att kognitiva tester från Betula-studien har signifikant samband med insjuknande i demens upp till 10 år innan klinisk demens bekräftats. Det finns dock inget dokumenterat försök att prediktera demens genom klassificering med kognitiva data från Betula-studien. Syftet med denna uppsats är att undersöka hur tre olika etablerade klassificeringsmetoder, linjär diskriminantanalys, support vector machines, med polynom och radial kärna, samt gradient tree boosting presterar på ett datamaterial med tre klasser. Data kommer från Betula-studien och består av kognitiva minnestester och persondata, klasserna bestäms utifrån hur många år efter inkludering i studien en deltagare blir diagnostiserad med klinisk demens. Klass 1 utvecklade inte demens, klass 2 utvecklade demens mellan 11 och 21 år och klass 3 mellan 1 och 10 år. Eftersom fördelningen av klasserna är obalanserade, klass 1 består av ca 85% av alla observationer, undersöks även en balanserad version av datamaterialet. Resultaten visar på en viss skillnad i fördelningen av korrekta och felaktiga klassificeringar för de olika metoderna. Vad gäller andelen korrekta och felaktiga klassificeringar kan inte någon betydande skillnad påvisas. Slutsatsen är att det inte går att avgöra om någon metod presterar bättre än de övriga.

  • Fröbert, Ole
    et al.
    Götberg, Matthias
    Angerås, Oskar
    Jonasson, Lena
    Erlinge, David
    Engstrøm, Thomas
    Persson, Jonas
    Jensen, Svend E.
    Omerovic, Elmir
    James, Stefan K.
    Lagerqvist, Bo
    Nilsson, Johan
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Kåregren, Amra
    Moer, Rasmus
    Yang, Cao
    Agus, David B.
    Erglis, Andrejs
    Jensen, Lisette O.
    Jakobsen, Lars
    Christiansen, Evald H.
    Pernow, John
    Design and rationale for the Influenza vaccination After Myocardial Infarction (IAMI) trial: a registry-based randomized clinical trial2017In: American Heart Journal, ISSN 0002-8703, E-ISSN 1097-6744, Vol. 189, 94-102 p.Article in journal (Refereed)
    Abstract [en]

    Background Registry studies and case-control studies have demonstrated that the risk of acute myocardial infarction (AMI) is increased following influenza infection. Small randomized trials, underpowered for clinical end points, indicate that future cardiovascular events can be reduced following influenza vaccination in patients with established cardiovascular disease. Influenza vaccination is recommended by international guidelines for patients with cardiovascular disease, but uptake is varying and vaccination is rarely prioritized during hospitalization for AMI. Methods/design The Influenza vaccination After Myocardial Infarction (IAMI) trial is a double-blind, multicenter, prospective, registry-based, randomized, placebo-controlled, clinical trial. A total of 4,400 patients with ST-segment elevation myocardial infarction (STEMI) or non-STEMI undergoing coronary angiography will randomly be assigned either to in-hospital influenza vaccination or to placebo. Baseline information is collected from national heart disease registries, and follow-up will be performed using both registries and a structured telephone interview. The primary end point is a composite of time to all cause death, a new AMI, or stent thrombosis at 1 year. Implications The IAMI trial is the largest randomized trial to date to evaluate the effect of in-hospital influenza vaccination on death and cardiovascular outcomes in patients with STEMI or non-STEMI. The trial is expected to provide highly relevant clinical data on the efficacy of influenza vaccine as secondary prevention after AMI.

  • Juto, Hans
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Orthopaedics.
    Gärtner Nilsson, Mattis
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Orthopaedics.
    Möller, Michael
    Wennergren, David
    Morberg, Per
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Orthopaedics.
    Evaluating non-responders of a survey in the Swedish fracture register: no indication of different functional result2017In: BMC Musculoskeletal Disorders, ISSN 1471-2474, E-ISSN 1471-2474, Vol. 18, 278Article in journal (Refereed)
    Abstract [en]

    Background: The Swedish Fracture Register (SFR) currently contains information on more than 190,000 fractures. Patient Reported Outcome Measures (PROMs) are used for monitoring functional results after fracture treatment. One weakness, as in many surveys, is a low response rate. The aim of the current study was to examine if non-responders of a survey in the SFR differ in PROMs scores, how age and gender influence the response rate and reasons for not responding. Methods: Patients with fractures of radius, ulna or humerus between June and August 2013 and registered in the SFR were included in the study. The non-responders to both the pre-injury and the 1-year survey were contacted by phone and reminded to reply. A comparison of the results of both EQ-5D and Short Musculoskeletal Function Assessment (SMFA) could be made between the responders after a phone reminder and the initial responders. The response rate for the register as a whole was extracted in order to identify how age and gender affect the response rate. Results: Three hundred seventeen of the patients included in the study responded initially. After phone reminder another 94 patients answered the pre-injury survey. Two hundred sixty eight responded initially to the 1-year follow-up survey and 42 after phone reminder. No significant difference was identified in the score of the pre-injury survey between initial responders and responders after phone reminder neither in the EQ-5D nor in the Short Musculoskeletal Function Assessment (SMFA). Regarding the 1-year survey, responders after a phone reminder reported a significantly better outcome in crude data of SMFA score. This difference disappeared after controlling for confounding factors through case control matching. The highest response rate to PROMs in the SFR was among females in the age range 60-69 years. Conclusion: This study indicates that both in the preinjury survey as well as in the 1-year survey the non-responders in the SFR report similar function compared to the initial responders. Age and gender of patients affect the response rate of the survey which needs to be taken into consideration in analysis of data from the SFR.

  • Prigge, Justin R.
    et al.
    Coppo, Lucia
    Martin, Sebastin S.
    Ogata, Fernando
    Miller, Colin G.
    Bruschwein, Michael D.
    Orlicky, David J.
    Shearn, Colin T.
    Kundert, Jean A.
    Lytchier, Julia
    Herr, Alix E.
    Mattsson, Åse
    Taylor, Matthew P.
    Gustafsson, Tomas N.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Bacteriology. Division of Biochemistry, Medical Biochemistry & Biophysics, Karolinska Institutet, Stockholm, Sweden.
    Arnér, Elias S. J.
    Holmgren, Arne
    Schmidt, Edward E.
    Hepatocyte Hyperproliferation upon Liver-Specific Co-disruption of Thioredoxin-1, Thioredoxin Reductase-1, and Glutathione Reductase2017In: Cell reports, ISSN 2211-1247, E-ISSN 2211-1247, Vol. 19, no 13, 2771-2781 p.Article in journal (Refereed)
    Abstract [en]

    Energetic nutrients are oxidized to sustain high intracellular NADPH/NADP(+) ratios. NADPH-dependent reduction of thioredoxin-1 (Trx1) disulfide and glutathione disulfide by thioredoxin reductase-1 (TrxR1) and glutathione reductase (Gsr), respectively, fuels antioxidant systems and deoxyribonucleotide synthesis. Mouse livers lacking both TrxR1 and Gsr sustain these essential activities using an NADPH-independent methionine-consuming pathway; however, it remains unclear how this reducing power is distributed. Here, we show that liver-specific co-disruption of the genes encoding Trx1, TrxR1, and Gsr (triplenull) causes dramatic hepatocyte hyperproliferation. Thus, even in the absence of Trx1, methionine-fueled glutathione production supports hepatocyte S phase deoxyribonucleotide production. Also, Trx1 in the absence of TrxR1 provides a survival advantage to cells under hyperglycemic stress, suggesting that glutathione, likely via glutaredoxins, can reduce Trx1 disulfide in vivo. In triple-null livers like in many cancers, deoxyribonucleotide synthesis places a critical yet relatively low-volume demand on these reductase systems, thereby favoring high hepatocyte turnover over sustained hepatocyte integrity.

  • Taj, Tahir
    et al.
    Malmqvist, Ebba
    Stroh, Emilie
    Oudin Åström, Daniel
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Occupational and Environmental Medicine. Center for Primary Health Care Research, Department of Clinical Science, Malmö, Lund University, Malmö, Sweden.
    Jakobsson, Kristina
    Oudin, Anna
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Occupational and Environmental Medicine. Department of Occupational and Environmental Medicine, Lund University, Lund, Sweden.
    Short-Term Associations between Air Pollution Concentrations and Respiratory Health-Comparing Primary Health Care Visits, Hospital Admissions, and Emergency Department Visits in a Multi-Municipality Study2017In: International Journal of Environmental Research and Public Health, ISSN 1661-7827, E-ISSN 1660-4601, Vol. 14, no 6, 587Article in journal (Refereed)
    Abstract [en]

    Acute effects of air pollution on respiratory health have traditionally been investigated with data on inpatient admissions, emergency room visits, and mortality. In this study, we aim to describe the total acute effects of air pollution on health care use for respiratory symptoms (ICD10-J00-J99). This will be done by investigating primary health care (PHC) visits, inpatient admissions, and emergency room visits together in five municipalities in southern Sweden, using a case-crossover design. Between 2005 and 2010, there were 81,019 visits to primary health care, 38,217 emergency room visits, and 25,271 inpatient admissions for respiratory symptoms in the study area. There was a 1.85% increase (95% CI: 0.52 to 3.20) in the number of primary health care visits associated with a 10 mu g/m(3) increase in nitrogen dioxide (NO2) levels in Malmo, but not in the other municipalities. Air pollution levels were generally not associated with emergency room visits or inpatient admissions, with one exception (in Helsingborg there was a 2.52% increase in emergency room visits for respiratory symptoms associated with a 10 mu g/m(3) increase in PM10). In conclusion, the results give weak support for short-term effects of air pollution on health care use associated with respiratory health symptoms in the study area.

  • Scholz, Saskia
    et al.
    Baharom, Faezzah
    Rankin, Gregory
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Maleki, Kimia T.
    Gupta, Shawon
    Vangeti, Sindhu
    Pourazar, Jamshid
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Discacciati, Andrea
    Höijer, Jonas
    Bottai, Matteo
    Björkström, Niklas K.
    Rasmuson, Johan
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Infectious Diseases.
    Evander, Magnus
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Virology.
    Blomberg, Anders
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Ljunggren, Hans-Gustaf
    Klingström, Jonas
    Ahlm, Clas
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Infectious Diseases.
    Smed-Sörensen, Anna
    Human hantavirus infection elicits pronounced redistribution of mononuclear phagocytes in peripheral blood and airways2017In: PLoS Pathogens, ISSN 1553-7366, E-ISSN 1553-7374, Vol. 13, no 6, e1006462Article in journal (Refereed)
    Abstract [en]

    Hantaviruses infect humans via inhalation of virus-contaminated rodent excreta. Infection can cause severe disease with up to 40% mortality depending on the viral strain. The virus primarily targets the vascular endothelium without direct cytopathic effects. Instead, exaggerated immune responses may inadvertently contribute to disease development. Mononuclear phagocytes (MNPs), including monocytes and dendritic cells (DCs), orchestrate the adaptive immune responses. Since hantaviruses are transmitted via inhalation, studying immunological events in the airways is of importance to understand the processes leading to immunopathogenesis. Here, we studied 17 patients infected with Puumala virus that causes a mild form of hemorrhagic fever with renal syndrome (HFRS). Bronchial biopsies as well as longitudinal blood draws were obtained from the patients. During the acute stage of disease, a significant influx of MNPs expressing HLA-DR, CD11c or CD123 was detected in the patients' bronchial tissue. In parallel, absolute numbers of MNPs were dramatically reduced in peripheral blood, coinciding with viremia. Expression of CCR7 on the remaining MNPs in blood suggested migration to peripheral and/or lymphoid tissues. Numbers of MNPs in blood subsequently normalized during the convalescent phase of the disease when viral RNA was no longer detectable in plasma. Finally, we exposed blood MNPs in vitro to Puumala virus, and demonstrated an induction of CCR7 expression on MNPs. In conclusion, the present study shows a marked redistribution of blood MNPs to the airways during acute hantavirus disease, a process that may underlie the local immune activation and contribute to immunopathogenesis in hantavirus-infected patients.

  • Webster, Steve J.
    et al.
    Brode, Sven
    Ellis, Lou
    Fitzmaurice, Timothy J.
    Elder, Matthew J.
    Gekara, Nelson O.
    Umeå University, Faculty of Medicine, Molecular Infection Medicine Sweden (MIMS). Umeå University, Faculty of Medicine, Umeå Centre for Microbial Research (UCMR). Umeå University, Faculty of Medicine, Department of Molecular Biology (Faculty of Medicine).
    Tourlomousis, Panagiotis
    Bryant, Clare
    Clare, Simon
    Chee, Ronnie
    Gaston, Hill J. S.
    Goodall, Jane C.
    Detection of a microbial metabolite by STING regulates inflammasome activation in response to Chlamydia trachomatis infection2017In: PLoS Pathogens, ISSN 1553-7366, E-ISSN 1553-7374, Vol. 13, no 6, e1006383Article in journal (Refereed)
    Abstract [en]

    The innate immune system is a critical component of host defence against microbial pathogens, but effective responses require an ability to distinguish between infectious and noninfectious insult to prevent inappropriate inflammation. Using the important obligate intracellular human pathogen Chlamydia trachomatis; an organism that causes significant immunopathology, we sought to determine critical host and pathogen factors that contribute to the induction of inflammasome activation. We assayed inflammasome activation by immunoblotting and ELISA to detect IL-1 beta processing and LDH release to determine pyroptosis. Using primary murine bone marrow derived macrophages or human monocyte derived dendritic cells, infected with live or attenuated Chlamydia trachomatis we report that the live organism activates both canonical and non-canonical inflammasomes, but only canonical inflammasomes controlled IL-1 beta processing which preceded pyroptosis. NADPH oxidase deficient macrophages were permissive to Chlamydia trachomatis replication and displayed elevated type-1 interferon and inflammasome activation. Conversely, attenuated, non-replicating Chlamydia trachomatis, primed but did not activate inflammasomes and stimulated reduced type-1 interferon responses. This suggested bacterial replication or metabolism as important factors that determine interferon responses and inflammasome activation. We identified STING but not cGAS as a central mediator of interferon regulated inflammasome activation. Interestingly, exogenous delivery of a Chlamydia trachomatis metabolite and STING ligand D cyclic di-AMP, recovered inflammasome activation to attenuated bacteria in a STING dependent manner thus indicating that a bacterial metabolite is a key factor initiating inflammasome activation through STING, independent of cGAS. These data suggest a potential mechanism of how the innate immune system can distinguish between infectious and non-infectious insult and instigate appropriate immune responses that could be therapeutically targeted.

  • Ljungberg, Johan
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Johansson, Bengt
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Engström, Karl Gunnar
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Albertsson, Elin
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Holmer, Paul
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Norberg, Margareta
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Epidemiology and Global Health.
    Bergdahl, Ingvar A.
    Umeå University, Faculty of Medicine, Department of Biobank Research.
    Söderberg, Stefan
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Cardiology.
    Traditional Cardiovascular Risk Factors and Their Relation to Future Surgery for Valvular Heart Disease or Ascending Aortic Disease: A Case-Referent Study2017In: Journal of the American Heart Association: Cardiovascular and Cerebrovascular Disease, ISSN 2047-9980, E-ISSN 2047-9980, Vol. 6, no 5, e005133Article in journal (Refereed)
    Abstract [en]

    Background: Risk factors for developing heart valve and ascending aortic disease are based mainly on retrospective data. To elucidate these factors in a prospective manner, we have performed a nested case-referent study using data from large, population-based surveys. Methods and Results: A total of 777 patients operated for heart valve disease or disease of the ascending aorta had previously participated in population-based health surveys in Northern Sweden. Median time (interquartile range) from survey to surgery was 10.5 (9.0) years. Primary indications for surgery were aortic stenosis (41%), aortic regurgitation (12%), mitral regurgitation (23%), and dilatation/dissection of the ascending aorta (17%). For each case, referents were allocated, matched for age, sex, and geographical area. In multivariable models, surgery for aortic stenosis was predicted by hypertension, high cholesterol levels, diabetes mellitus, and active smoking. Surgery for aortic regurgitation was associated with a low cholesterol level, whereas a high cholesterol level predicted surgery for mitral regurgitation. Hypertension, blood pressure, and previous smoking predicted surgery for disease of the ascending aorta whereas diabetes mellitus was associated with reduced risk. After exclusion of cases with coronary atherosclerosis, only the inverse associations between cholesterol and aortic regurgitation and between diabetes mellitus and disease of the ascending aorta remained. Conclusions: This is the first truly prospective study of traditional cardiovascular risk factors and their association with valvular heart disease and disease of the ascending aorta. We confirm the strong association between traditional risk factors and aortic stenosis, but only in patients with concomitant coronary artery disease. In isolated valvular heart disease, the impact of traditional risk factors is varying.

  • Claesson, Rolf
    et al.
    Umeå University, Faculty of Medicine, Department of Odontology.
    Höglund-Åberg, Carola
    Umeå University, Faculty of Medicine, Department of Odontology.
    Haubek, Dorte
    Johansson, Anders
    Umeå University, Faculty of Medicine, Department of Odontology.
    Age-related prevalence and characteristics of Aggregatibacter actinomycetemcomitans in periodontitis patients living in Sweden2017In: Journal of Oral Microbiology, ISSN 2000-2297, E-ISSN 2000-2297, Vol. 9, 1334504Article in journal (Refereed)
    Abstract [en]

    Background: The presence of Aggregatibacter actinomycetemcomitans in patients with periodontitis has been extensively studied for decades. Objective: To study the prevalence of A. actinomycetemcomitans in younger and older periodontitis patients and to genetically characterize isolates of this bacterium. Design: Data from microbiological analyses of 3459 subgingival plaque samples collected from 1445 patients, 337 'younger' patients (<= 35 yrs) and 1108 'older' patients (>35 yrs) during 15 years (2000-2014), has been summerized. Isolates of A. actinomycetemcomitans were serotyped, leukotoxin promoter typed (JP2 and non JP2) and arbitrarily primed PCR (APPCR) genotyped. The origin of the JP2 genotype detected in the study population was determined. Results: The prevalence of A. actinomycetemcomitans was higher among younger than older patients and samples from the younger patients contained higher proportions of the bacterium. Serotype b was more prevalent among younger patients and the majorty of these isolates was from the same AP-PCR genotype. The JP2 genotype was detected in 1.2% of the patients, and the majority of these carriers were of non-African origin. Conslusions: For presence and charcteristics of A. actinomycetemcomitans in clinical samples the age of the carriers were a discriminating factor. Additional, apparently non- African carriers of the JP2 genotype of A. actinomycetemcomitans were identified.

  • Magnusson, Rebecca
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Effects of litter quality and latitude on decomposition.2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Decomposition of organic material (litter) is an important part of the global carbon cycle. Environmental conditions, litter quality and the microbial community are the main factors affecting decomposition. The decomposition is divided into two phases, one fast initial phase and one slow second phase. The tea bag index (TBI) was used as a standardized method to measure decomposition rate along a latitudinal gradient. A common garden set up and extractions were made to determine the composition of the litter to investigate if climate or litter quality affected the decomposition rate. The result showed that the decomposition rate increased with higher latitude. The litter from higher latitude has more material that is easy to decompose. Natural litter abroad had higher decomposition rate than at home. On the contrary, standard litter at home had higher decomposition rate than abroad. This indicates that litter quality is more important than latitude. Further studies are needed with more sites along the gradient to conclude how climate and litter quality are affecting decomposition.   

  • Tao, Liang
    et al.
    Peng, Lisheng
    Berntsson, Ronnie P. -A.
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics. Department of Biochemistry and Biophysics, Stockholm University, Stockholm, Sweden.
    Liu, Sai Man
    Park, SunHyun
    Yu, Feifan
    Boone, Christopher
    Palan, Shilpa
    Beard, Matthew
    Chabrier, Pierre-Etienne
    Stenmark, Pål
    Krupp, Johannes
    Dong, Min
    Engineered botulinum neurotoxin B with improved efficacy for targeting human receptors2017In: Nature Communications, ISSN 2041-1723, E-ISSN 2041-1723, Vol. 8, 53Article in journal (Refereed)
    Abstract [en]

    Botulinum neurotoxin B is a Food and Drug Administration-approved therapeutic toxin. However, it has lower binding affinity toward the human version of its major receptor, synaptotagmin II (h-Syt II), compared to mouse Syt II, because of a residue difference. Increasing the binding affinity to h-Syt II may improve botulinum neurotoxin B's therapeutic efficacy and reduce adverse effects. Here we utilized the bacterial adenylate cyclase two-hybrid method and carried out a saturation mutagenesis screen in the Syt II-binding pocket of botulinum neurotoxin B. The screen identifies E1191 as a key residue: replacing it with M/C/V/Q enhances botulinum neurotoxin B binding to human synaptotagmin II. Adding S1199Y/W or W1178Q as a secondary mutation further increases binding affinity. Mutant botulinum neurotoxin B containing E1191M/S1199Y exhibits similar to 11-fold higher efficacy in blocking neurotransmission than wild-type botulinum neurotoxin B in neurons expressing human synaptotagmin II, demonstrating that enhancing receptor binding increases the overall efficacy at functional levels. The engineered botulinum neurotoxin B provides a platform to develop therapeutic toxins with improved efficacy.