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  • Public defence: 2017-06-14 14:00 sal E306, Arrheniuslaboratorierna, Stockholm
    Olsen, Jessica M.
    Stockholm University, Faculty of Science, Department of Molecular Biosciences, The Wenner-Gren Institute.
    β-Adrenergic Signalling Through mTOR2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Adrenergic signalling is part of the sympathetic nervous system and is activated upon stimulation by the catecholamines epinephrine and norepinephrine. This regulates heart rate, energy mobilization, digestion and helps to divert blood flow to important organs. Insulin is released to regulate metabolism of carbohydrates, fats and proteins, mainly by taking up glucose from the blood. The insulin and the catecholamine hormone systems are normally working as opposing metabolic regulators and are therefore thought to antagonize each other.

    One of the major regulators involved in insulin signalling is the mechanistic target of rapamycin (mTOR). There are two different complexes of mTOR; mTORC1 and mTORC2, and they are essential in the control of cell growth, metabolism and energy homeostasis. Since mTOR is one of the major signalling nodes for anabolic actions of insulin it was thought that catecholamines might oppose this action by inhibiting the complexes. However, lately there are studies demonstrating that this may not be the case. mTOR is for instance part of the adrenergic signalling pathway resulting in hypertrophy of cardiac and skeletal muscle cells and inhibition of smooth muscle relaxation and helps to regulate browning in white adipose tissue and thermogenesis in brown adipose tissue (BAT).

    In this thesis I show that β-adrenergic signalling leading to glucose uptake occurs independently of insulin in skeletal muscle and BAT, and does not activate either Akt or mTORC1, but that the master regulator of this pathway is mTORC2. Further, my co-workers and I demonstrates that β-adrenergic stimulation in skeletal muscle and BAT utilizes different glucose transporters. In skeletal muscle, GLUT4 is translocated to the plasma membrane upon stimulation. However, in BAT, β-adrenergic stimulation results in glucose uptake through translocation of GLUT1. Importantly, in both skeletal muscle and BAT, the role of mTORC2 in β-adrenergic stimulated glucose uptake is to regulate GLUT-translocation.

  • Public defence: 2017-06-14 13:00 Lilla hörsalen, NOD-huset, Kista
    Uppström, Elin
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Designing, Theorizing, and Reflecting on Information Systems Artifacts and Value Co-Creation in e-Government2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    E-government services in the form of information systems (IS) artifacts create a new arena for co-creation that governments aim to leverage. Design of and knowledge about IS artifacts in value co-creation in e-government can thereby be considered valuable for the future development of e-government. How IS artifacts are used in value co-creation and co-destruction and how the artifacts are developed is however not well understood.

    This thesis addresses the problem of how to design for and understand value co-creation in e-government. To address the problem stated, three research questions are posed. (i) How can IS artifacts be designed to enable value co-creation in e-government and what aspects can inhibit value being co-created through the designed artifacts? (ii) How can boundary object theory facilitate the understanding of IS artifacts used in value co-creation and co-destruction in e-government? (iii) How can retrospectives in design science contribute to research on value co-creation in e-government?

    Two artifacts in the form of instantiations are designed and evaluated. Design science research methodology is used in two different projects at Swedish municipalities. Secondary analysis is used to identify aspects that inhibit value being co-created through the designed IS artifacts. From these inhibitors, core aspects for public value co-creation are derived. Thereafter, this thesis delves further into how IS artifacts are used in collaborations between citizens, private businesses, and government agencies in order to co-create value. Two case studies are carried out at Swedish government agencies and sociomaterial boundary object theory is used to enhance understanding. The thesis research process ends with a retrospective evaluation of the performed research, using critical realism as its philosophical foundation and guidance.

    The result includes one configurable process model that enables value co-creation by facilitating shared understanding between collaborating parties; one mobile service that enables value co-creation through citizen sourcing; aspects that inhibit the realization of co-created value; and four core aspects that need to be considered when designing artifacts for value co-creation. That IS artifacts can be regarded as boundary objects when you aim to study and understand value co-creation and co-destruction between communities in e-government. Descriptions of how IS artifacts, viewed as sociomaterial boundary objects, are used in value co-creation processes between governments, citizens, and businesses and outcomes in terms of value co-creation and co-destruction. The benefit of performing critical realism-guided retrospectives in design science in order to complement prescriptive knowledge with explanatory and critical knowledge is motivated. It is showed that the design of artifacts generates knowledge through the design efforts, regardless of whether they also yield utility.

    This thesis contributes to e-government research and practice with knowledge on how to design artifacts that enable value co-creation. Establishes sociomaterial boundary object theory as a theoretical lens that offers a tool to evaluate and design IS artifacts that enable value co-creation and with knowledge on how IS artifacts are used in value co-creation. The thesis also motivates the usefulness of retrospective evaluation in design science. Suggestions for future research include further developing design science retrospectives. 

  • Public defence: 2017-06-16 13:00 hörsal 3, hus B, Stockholm
    Quartararo, Geraldine
    Stockholm University, Faculty of Humanities, Department of Romance Studies and Classics.
    Evidencialidad indirecta en aimara y en el español de La Paz: Un estudio semántico-pragmático de textos orales2017Doctoral thesis, monograph (Other academic)
    Abstract [en]

    This dissertation investigates the expression of the indirect evidential subdomain in two languages in contact, i.e. the northern variety of Central Aymara and the variety of Spanish spoken in La Paz (Bolivia).

    For this aim, the study uses first-hand data collected in La Paz and El Alto (Bolivia) during 2014 and 2015. Data was elicited through: the “Family Problems Picture” task (San Roque et al. 2012), formulated by the members of the Max Planck Institute for Psycholinguistics and created specifically for the activation of cognitive categories such as evidentiality and mirativity; the “Pear Story” designed for Wallace Chafe, professor at the University of California, to collect narrative texts that show how humans perceive, elaborate and verbalize experience; and, finally, personal narratives, traditional narratives and interviews. Thirty-three recordings (12h 48’) of 48 Spanish-Aymara bilingual speakers (17 males, age range: 18-64) were fully transcribed and annotated. The resulting corpus consists of 33 transcriptions of which 14 are in Aymara (c. 19 154 words), whereas 19 are in Spanish (c. 46 245 words).

    The dissertation is built around four research questions.

    First, the dissertation shows the functions of the forms identified in the data in both languages. The study identifies for each form both evidential and non-evidential functions. Indirect evidential functions are systematically analyzed and classified by combining Willett’s (1988) and Aikhnvald’s (2004) classifications. The analysis shows evidential functions of forms that have not been previously studied as such, i.e. digamos and diciendo in Spanish and sañani and sapxi in Aymara, but it also reveals unnoticed evidential functions for previously described forms.

    Second, the dissertation provides a clear view of the relationship between the evidential and the epistemic modal domain involved in the use of the forms identified. Two types of correlation are found. Both languages, indeed, show forms that only point out the way in which speakers acquired information and forms where the two domains overlap.

    Third, the dissertation investigates speakers’ epistemic stance, in terms of commitment, towards information involved in the use of the evidential forms identified. The study shows that the forms which convey merely evidential information express mainly a medium-high commitment degree, whereas the forms in which the distinction between the evidential and the epistemic modal domain is blurred indicate a low degree of commitment.

    Forth, the dissertation sheds light on the relationship between the expressions of the indirect evidential subdomain in the two languages. The study proposes a quantitative and qualitative analysis of the evidential types and subtypes in both languages. The results show a high degree of convergence between the two languages, suggesting also situations of influence of one language on the other.

  • Public defence: 2017-06-16 14:00 William-Olssonsalen, Geovetenskapens hus, Stockholm
    Öberg, Erik
    Stockholm University, Faculty of Social Sciences, Department of Economics.
    On Money and Consumption2017Doctoral thesis, monograph (Other academic)
    Abstract [en]

    Price Level Determination When Tax Payments Are Required in Money. We formalize the idea that the price level can be determined by a requirement that taxes be paid in money. We show that if households have to pay a money tax of a fixed real value and the money supply is constant, there is a unique stationary price level, and a continuum of non-stationary deflationary equilibria. The non-stationary equilibria can be excluded if we introduce an arbitrarily lax borrowing constraint. Thus, in the basic model, tax requirements can uniquely determine the price level. When money has liquidity value, tax requirements can exclude self-fulfilling hyperinflations.

    The New Keynesian Transmission Mechanism: A Heterogeneous-Agent Perspective. We argue that a two-agent version of the standard New Keynesian model - where a "worker'' receives only labor income and a "capitalist'' only profit income - offers insights about how income inequality affects the monetary transmission mechanism. Under rigid prices, monetary policy has no effect on output as workers choose not to change their hours worked in response to wage movements. In the corresponding representative-agent model, in contrast, hours do rise after a monetary policy loosening due to a wealth effect on labor supply: profits fall, thus reducing the representative worker's income. If wages are rigid too, however, the monetary transmission mechanism is active and resembles that in the corresponding representative-agent model.

    Consumption Dynamics under Time-varying Unemployment Risk. We argue that adjustment frictions for durable goods generate a powerful amplification channel from fluctuations in unemployment risk to aggregate consumption demand. First, we use survey data to document that durable expenditures react strongly to increased unemployment risk, while the effect on nondurable expenditures is indistinguishable from zero. Second, we propose and calibrate a buffer-stock savings model that includes adjustment frictions for durable goods. Although not targeted in the calibration, we find that the model reproduces the semi-elasticities of expenditures to unemployment risk estimated in the data. Using the model, we find that the inclusion of adjustment frictions raises the aggregate demand response of durable goods to fluctuations in perceived unemployment risk by approximately 200 percent. Moreover, upon experiencing an adverse risk shock, the responsiveness of aggregate demand for durable goods to the interest rate and transitory income shocks is dampened.

    Consumption Dynamics under Time-varying Unemployment Risk: Evidence from Time Series Data. We investigate the relationship between consumption expenditures and unemployment risk using aggregate time series data for the US and ten EU countries. As a proxy for perceived unemployment risk, we use data on households' subjective expectations over the future unemployment rate. First, we employ a single-equation framework to test whether subjective unemployment expectations predict aggregate consumption growth when controlling for predicted aggregate income growth. Second, we exploit the timing of the survey interviews in relation to the publication of official statistics to isolate exogenous innovations to unemployment expectations in a small-scale vector autoregression. For the US, both methods suggest that there is a large effect of unemployment risk on aggregate consumption. For the ten EU countries, the evidence is mixed.

  • Public defence: 2017-06-16 13:00 Nordenskiöldsalen, Geovetenskapens hus, Stockholm
    Weiss, Niels
    Stockholm University, Faculty of Science, Department of Physical Geography.
    Permafrost carbon in a changing Arctic: On periglacial landscape dynamics, organic matter characteristics, and the stability of a globally significant carbon pool2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Organic matter (OM) in arctic permafrost ground contains about twice as much carbon (C) as is currently present in the atmosphere. Climate change is particularly strong in the Arctic, and could cause a considerable part of the OM in permafrost to thaw out, decompose, and be released as greenhouse gases; further enhancing global warming. The exact size of the northern circumpolar C pool remains unclear, and processes that control decomposition and mineralization rates are even more uncertain. Superimposed on the long-term release of C through microbial decomposition of OM in the gradually deepening active layer, is the rapid release of currently sequestered OM through geomorphological processes. This thesis considers the quantity, quality, and availability of permafrost C, and explores interactions and common controls.

    To better understand the potential effects of thawing permafrost, it is vital to: i) obtain more accurate size and distribution estimates of permafrost C stocks, and develop methods to accurately and efficiently implement these in models, ii) identify OM characteristics that control decomposition, specifically for permafrost material, and iii) determine and quantify key geomorphological processes that cause large amounts of OM to become available for rapid decomposition.

    Detailed C quantifications are valuable to increase our fundamental understanding of permafrost soil processes and C sequestration, but including high levels of heterogeneity in models is challenging. Simple upscaling tools based on e.g. elevation parameters (Paper I) can help to bridge the gap between detailed field studies and global C models.

    Permafrost OM quality is controlled by different factors than those commonly observed in temperate soils (without permafrost). We observed an unexpected (significant) correlation in upper permafrost samples, where material that is generally considered more recalcitrant showed the highest CO2 production rates per g C, indicating high lability (Paper II). In ancient Pleistocene permafrost, labile samples related significantly to OM that was enriched in decomposed microbial remains, whereas less-decomposed plant material was more stable (Paper III). Investigation of multiple incubation datasets revealed that the unusual relationship between %C and CO2 production occurred in contrasting field sites throughout the Arctic, indicating important permafrost-specific controls over OM quality (Paper IV). We discuss several possible explanations for the observed high lability of permafrost OM, such as a pool of labile dissolved organic C in the upper permafrost, or increased lability caused by past decomposition. In order to conclusively identify causal relationships, and to answer the question whether or not the same mechanisms control OM quality in different environments, further investigation of permafrost-specific OM quality is required.

    Geomorphology plays a key role in C reworking and OM decomposition. Vast amounts of OM can be released abruptly (e.g. in thaw slumps and thermokarst lakes, Paper II), resulting in C turnover that will likely outweigh decomposition through gradual active layer deepening. Climate change could enhance this rapid release of C, and changes in surface hydrology and increased fire activity are expected to become the largest contributors to C loss from permafrost regions. Together with C quantity and quality, availability through gradual and abrupt processes must be parameterized and included in models in order to accurately assess the potential permafrost C climate feedback.

  • Tomasson, Torkel
    Institute for Language and Folklore, Department of Dialectology and Folklore Research, Uppsala.
    Rydving, Håkan (Editor)
    Institute for Language and Folklore, Department of Dialectology and Folklore Research, Uppsala.
    Några sägner, seder och bruk upptecknade efter lapparna i Åsele- och Lycksele lappmark samt Herjedalen sommaren 19171988Book (Other academic)
  • Public defence: 2017-06-14 10:00 Auditoriet, Humanistvillan, Stockholm
    Israelson, Per
    Stockholm University, Faculty of Humanities, Department of Culture and Aesthetics.
    Ecologies of the Imagination: Theorizing the participatory aesthetics of the fantastic2017Doctoral thesis, monograph (Other academic)
    Abstract [en]

    This book is about the participatory aesthetics of the fantastic. In it, the author argues that the definition of the fantastic presented by Tzvetan Todorov in 1970 can be used, provided it is first adapted to a media-ecological framework, to theorize the role of aesthetic participation in the creation of secondary worlds. Working within a hermeneutical tradition, Todorov understands reader participation as interpretation, in which the creative ambiguities of the literary object are primarily epistemological. However, it is here argued that the aesthetic object of the fantastic is also characterized by material ambiguity.

    The purpose of this dissertation is then to present a conceptual framework with which to theorize the relation between the material and the epistemological ambiguity of the fantastic. It is argued that such a framework can be found in an ecological understanding of aesthetic participation. This, in turn, entails understanding human subjectivity as a process always already embodied in a material environment. To this extent, the proposed theoretical framework questions the clear and oppositional distinction between form and matter, as well as that between mind and body, nature and culture, and human and non-human, on which a modern and humanist notion of subjectivity is based. And in this sense, the basic ecological assumptions of this dissertation are posthumanist, or non-humanist. From this position, it is argued that an ecological understanding of participation offers a means to reformulate the function of a number of concepts central to studying the aesthetics of the fantastic, most notably the concepts of media, genre and text. As the fantastic focuses on the creation of other worlds, it is an aesthetics of coming into being, of ontogenesis. Accordingly, it will be argued that the participatory aesthetics of the fantastic operationalizes the ontogenesis of media, genres and texts.

    By mapping the ontogenesis of three distinct media ecologies – the media ecology of fantasy and J. R. R. Tolkien’s secondary world Middle-earth; the media ecology of the American comic book superhero Miracleman; and the media ecology of William Blake – this book argues that the ecological imagination generates world.

    Per Israelson has been a doctoral candidate in the Research School of Studies in Cultural History at the department of Culture and Aesthetics, Stockholm University. Ecologies of the Imagination is his dissertation.

  • Public defence: 2017-05-29 10:15 F3, Stockholm
    Sack, Stefan
    KTH, School of Engineering Sciences (SCI), Centres, Linné Flow Center, FLOW. KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering, Marcus Wallenberg Laboratory MWL.
    Experimental and Numerical Multi-port Eduction for Duct Acoustics2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Sound generation and propagation in circular ducts for frequencies beyond the cut-on frequencies of several higher order acoustic modes is investigated. To achieve this, experimental and numerical set-ups are designed and used to research aeroacoustic interactions between in-duct components and to conceive noise mitigation strategies.

    Describing in-duct sound for frequencies with a moderate number of propagating modes is important, for example, for improving the noise emission from mid-size ventilation systems. Challenges that are largely unacknowledged in the literature involve efficient test rig design, quantification of limits in the methods, numerical modelling, and development of effective noise mitigation strategies for higher order modes.

    In this thesis, in-duct sound is mapped on a set of propagating pressure eigenmodes to describe aeroacoustic components as multi-ports with sound scattering (passive properties) and a source strength (active properties). The presented analysis includes genetic algorithms and Monte Carlo Methods for test rig enhancement and evaluation, multi-port network predictions to identify model limitations, and scale resolving (IDDES) and Linearized Navier Stokes computations for numerical multi-port eduction and the silencer design.

    It is first shown that test rig optimization improves the quality of multi-port data significantly. Subsequently, measurements on orifice plates are used to test the network prediction model. The model works with high accuracy for two components that are sufficiently separated. For small separations, strong coupling effects are observed for the source strength but not for the scattering of sound. The measurements are used for numerical validation, which gives reliable results for coupled and uncoupled systems. The total acoustic power of tandem orifices is predicted with less than 2 dB deviation and the passive properties for most frequencies with less than 5 % difference from the measurement. The numerical (FEM) models are also used to design a completely integrated silencer for spinning modes that is based on micro-perforated plates and gives broadband attenuation of 3-6 dB per duct diameter silencer length.

    The multi-port method is a powerful tool when describing aerodynamically decoupled in-duct components in the low- to mid-frequency range. Due to a robust passive network prediction, multi-port methods are particular interesting for the design of silencer stages. Furthermore, the demonstrated applicability to numerical data opens novel application areas.

  • Public defence: 2017-06-08 10:00 Brinellsalen M311, Stockholm
    A Asif, Farazee M
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Machine and Process Technology.
    Circular Manufacturing Systems: A development framework with analysis methods and tools for implementation2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The society today lives on the philosophy of ‘take-make-use-dispose.’ In the long run, this is not sustainable as the natural resources and the waste carrying capacity of the earth are limited. Therefore, it is essential to reduce dependency on the natural resources by decoupling the growth from the consumption. In this venture, both the society and the manufacturing industry have a vital role to play. The society needs to shift towards Circular Economy that rests upon the philosophy of ‘take-make-use-reuse’ and the manufacturing industry has to be a major stakeholder in this shift. Despite being proven to be both economically and environmentally beneficial, successful examples of circular systems are few today. This is primarily due to two reasons; firstly, there is a lack of systemic and systematic approach to guide industries and secondly, there is a lack of analysis methods and tools that are capable of assessing different aspects of circular manufacturing systems. Taking on to these challenges, the objective of this research is to bring forward a framework with methods and decision support tools that are essential to implement circular manufacturing systems. The initial conceptual framework with the systemic approach is developed based on extensive review and analysis of research, which is further adapted for industrial implementation. Systematic analysis methods, decision support and implementation tools are developed to facilitate this adaptation. This development has been supported by four cases from diverse manufacturing sectors. Behind each decision support tool, there are analysis methods built upon mainly system dynamics principles. These tools are based on simulation platforms called Stella and Anylogic. Among other things, these tools are capable of assessing the performance of closed-loop supply chains, consequences of resource scarcity, potential gains from resource conservation and overall economic and environmental performance of circular manufacturing systems.

  • Public defence: 2017-06-12 09:00 Hörsal D, Umeå
    D'Ascenzi, Flavio
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine.
    Atrial function and loading conditions in athletes2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Intensive training is associated with hemodynamic changes that typically induce an enlargement of cardiac chamber. Despite LA dilatation in athletes has been interpreted as a benign adaptation, little evidence is available. The aim of this thesis is to demonstrate that LA size changes in response to alterations in loading conditions and to analyse atrial myocardial function in athletes through the application of novel echocardiographic techniques.

    We found that top-level athletes exhibit a dynamic morphological and functional LA remodelling, induced by training, with an increase in reservoir and conduit volumes, but stable active volume. Training causes an increase in biatrial volumes which is accompanied by normal filling pressures and stiffness. These changes in atrial morphology are not associated with respective electrical changes. Extending the evidence from adult athletes to children, we found that training-induced atrial remodelling can occur in the early phases of the sports career and is associated with a preserved biatrial function. Finally, in a meta-analysis study of the available evidence we demonstrated that atrial function and size are not affected by aging.

    In conclusions, athlete’s heart is characterized by a physiological biatrial enlargement. This adaptation occurs in close association with LV cavity enlargement, is dynamic and reversible. This increase in biatrial size is not intrinsically an expression of atrial dysfunction. Indeed, in athletes the atria are characterized by a preserved reservoir function, normal myocardial stiffness, and dynamic changes in response to different loading conditions.

  • Tegenu, Tsegaye
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Social and Economic Geography.
    Youth Bulge in Cities and Towns, its Remedies2017Other (Other (popular science, discussion, etc.))
  • Tegenu, Tsegaye
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Social and Economic Geography.
    100 Million People Economic System in Ethiopia2017Other (Other (popular science, discussion, etc.))
  • Daerga, Per-Anders
    et al.
    f.d. Umeå universitet.
    Girhammar, Ulf Arne
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Programmering av Matlab-rutiner för utvärdering av experiment med knutpunktsförband i MFB-systemet: Beröringsfr imätning av krafter och deformationer med Qualisys Motion Capture – Beskrivning av mätsystem och efterbehandling av mätdata2017Report (Other (popular science, discussion, etc.))
  • Simons, Gregory
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Uppsala Centre for Russian and Eurasian Studies. Swedish Defence University.
    ‘Good’ Battles and ‘Bad’ Battles: A Comparative Analysis of Western Media Coverage of the Battles of Mosul and Aleppo2017In: Tractus Aevorum, ISSN 2312-3044, Vol. 3, no 2, 114-138 p.Article in journal (Refereed)
    Abstract [en]

    The author examines the coverage of two simultaneously occurring battles, Mosul and Aleppo, in the Western media. Although both battles are intended to be key moments in defeating terrorist organisations, there is a stark contrast in the Western media`s framing of these events. In order to analyse the vast gaps in the coverage of these battles, the lens of news management, which is a means to influence public perception and opinion, is employed to view these two distinct events in Iraq and Syria. The author concludes that news management is applied to the information flows in these events in order to shape public opinion and perception of the battles Mosul and Aleppo—one ‘good’ and the other ‘bad.’

  • Hernandez, Alison
    et al.
    Ruano, Ana Lorena
    Marchal, Bruno
    San Sebastián, Miguel
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine.
    Flores, Walter
    Engaging with complexity to improve the health of indigenous people: a call for the use of systems thinking to tackle health inequity2017In: International Journal for Equity in Health, ISSN 1475-9276, E-ISSN 1475-9276, Vol. 16, 26Article in journal (Refereed)
    Abstract [en]

    The 400 million indigenous people worldwide represent a wealth of linguistic and cultural diversity, as well as traditional knowledge and sustainable practices that are invaluable resources for human development. However, indigenous people remain on the margins of society in high, middle and low-income countries, and they bear a disproportionate burden of poverty, disease, and mortality compared to the general population. These inequalities have persisted, and in some countries have even worsened, despite the overall improvements in health indicators in relation to the 15-year push to meet the Millennium Development Goals. As we enter the Sustainable Development Goals (SDGs) era, there is growing consensus that efforts to achieve Universal Health Coverage (UHC) and promote sustainable development should be guided by the moral imperative to improve equity. To achieve this, we need to move beyond the reductionist tendency to frame indigenous health as a problem of poor health indicators to be solved through targeted service delivery tactics and move towards holistic, integrated approaches that address the causes of inequalities both inside and outside the health sector. To meet the challenge of engaging with the conditions underlying inequalities and promoting transformational change, equity-oriented research and practice in the field of indigenous health requires: engaging power, context-adapted strategies to improve service delivery, and mobilizing networks of collective action. The application of systems thinking approaches offers a pathway for the evolution of equity-oriented research and practice in collaborative, politically informed and mutually enhancing efforts to understand and transform the systems that generate and reproduce inequities in indigenous health. These approaches hold the potential to strengthen practice through the development of more nuanced, context-sensitive strategies for redressing power imbalances, reshaping the service delivery environment and fostering the dynamics of collective action for political reform.

  • Yen, Amy Ming-Fang
    et al.
    Wu, Wendy Yi-Ying
    Umeå University, Faculty of Medicine, Department of Radiation Sciences. Graduate Institute of Epidemiology and Preventive Medicine, College of Public Health, National Taiwan University, Taipei, Taiwan.
    Tabar, Laszlo
    Duffy, Stephen W.
    Smith, Robert A.
    Chen, Hsiu-Hsi
    Initiators and promoters for the occurrence of screen-detected breast cancer and the progression to clinically-detected interval breast cancer2017In: Journal of Epidemiology, ISSN 0917-5040, E-ISSN 1349-9092, Vol. 27, no 3, 98-106 p.Article in journal (Refereed)
    Abstract [en]

    Background: The risk factors responsible for breast cancer have been well documented, but the roles of risk factors as initiators, causing the occurrence of screen-detected breast cancer, or promoters, responsible for the progression of the screen-detected to the clinically-detected breast cancer, have been scarcely evaluated.

    Methods: We used data from women in a cohort in Kopparberg (Dalarna), Sweden between 1977 and 2010. Conventional risk factors, breast density, and tumor-specific biomarkers are superimposed to the temporal course of the natural history of the disease.

    Results: The results show that older age at first full-term pregnancy, dense breast, and a family history of breast cancer increased the risk of entering the preclinical screen-detectable phase of breast cancer by 23%, 41%, and 89%, respectively. Overweight/obesity (body mass index >= 25 kg/m(2)) was a significant initiator (adjusted relative risk [aRR] 1.15; 95% confidence interval [CI], 0.99-1.33), but was inversely associated with the role of promoter (aRR 0.65; 95% CI, 0.51-0.82). Dense breast (aRR 1.46; 95% CI, 1.12 -1.91), triple-negative (aRR 2.07; 95% CI, 1.37-3.15), and Ki-67 positivity (aRR 1.66; 95% CI, 1.19-2.30) were statistically significant promoters. When the molecular biomarkers were considered collectively as one classification, the basal-like subtype was the most influential subtype on promoters (aRR 4.24; 95% CI, 2.56-7.02) compared with the Luminal A subtype.

    Discussion: We ascertained state-dependent covariates of initiators and promoters to classify the risk of the two-step progression of breast cancer. The results of the current study are useful for individually-tailored screening and personalized clinical surveillance of patients with breast cancer that was detected at an early stage.

  • Doublet, Vincent
    et al.
    Poeschl, Yvonne
    Gogol-Doering, Andreas
    Alaux, Cedric
    Annoscia, Desiderato
    Aurori, Christian
    Barribeau, Seth M.
    Bedoya-Reina, Oscar C.
    Brown, Mark J. F.
    Bull, James C.
    Flenniken, Michelle L.
    Galbraith, David A.
    Genersch, Elke
    Gisder, Sebastian
    Grosse, Ivo
    Holt, Holly L.
    Hultmark, Dan
    Umeå University, Faculty of Medicine, Department of Molecular Biology (Faculty of Medicine).
    Lattorff, H. Michael G.
    Le Conte, Yves
    Manfredini, Fabio
    McMahon, Dino P.
    Moritz, Robin F. A.
    Nazzi, Francesco
    Nino, Elina L.
    Nowick, Katja
    van Rij, Ronald P.
    Paxton, Robert J.
    Grozinger, Christina M.
    Unity in defence: honeybee workers exhibit conserved molecular responses to diverse pathogens2017In: BMC Genomics, ISSN 1471-2164, E-ISSN 1471-2164, Vol. 18, 207Article in journal (Refereed)
    Abstract [en]

    Background: Organisms typically face infection by diverse pathogens, and hosts are thought to have developed specific responses to each type of pathogen they encounter. The advent of transcriptomics now makes it possible to test this hypothesis and compare host gene expression responses to multiple pathogens at a genome-wide scale. Here, we performed a meta-analysis of multiple published and new transcriptomes using a newly developed bioinformatics approach that filters genes based on their expression profile across datasets. Thereby, we identified common and unique molecular responses of a model host species, the honey bee (Apis mellifera), to its major pathogens and parasites: the Microsporidia Nosema apis and Nosema ceranae, RNA viruses, and the ectoparasitic mite Varroa destructor, which transmits viruses.

    Results: We identified a common suite of genes and conserved molecular pathways that respond to all investigated pathogens, a result that suggests a commonality in response mechanisms to diverse pathogens. We found that genes differentially expressed after infection exhibit a higher evolutionary rate than non-differentially expressed genes. Using our new bioinformatics approach, we unveiled additional pathogen-specific responses of honey bees; we found that apoptosis appeared to be an important response following microsporidian infection, while genes from the immune signalling pathways, Toll and Imd, were differentially expressed after Varroa/virus infection. Finally, we applied our bioinformatics approach and generated a gene co-expression network to identify highly connected (hub) genes that may represent important mediators and regulators of anti-pathogen responses.

    Conclusions: Our meta-analysis generated a comprehensive overview of the host metabolic and other biological processes that mediate interactions between insects and their pathogens. We identified key host genes and pathways that respond to phylogenetically diverse pathogens, representing an important source for future functional studies as well as offering new routes to identify or generate pathogen resilient honey bee stocks. The statistical and bioinformatics approaches that were developed for this study are broadly applicable to synthesize information across transcriptomic datasets. These approaches will likely have utility in addressing a variety of biological questions.

  • Poveda, Alaitz
    et al.
    Chen, Yan
    Brändström, Anders
    Umeå University, Faculty of Social Sciences, Centre for Demographic and Ageing Research (CEDAR).
    Engberg, Elisabeth
    Umeå University, Faculty of Social Sciences, Centre for Demographic and Ageing Research (CEDAR).
    Hallmans, Göran
    Umeå University, Faculty of Medicine, Department of Biobank Research.
    Johansson, Ingegerd
    Umeå University, Faculty of Medicine, Department of Biobank Research.
    Renström, Frida
    Umeå University, Faculty of Medicine, Department of Biobank Research. Genetic and Molecular Epidemiology Unit, Department of Clinical Sciences, Clinical Research Centre, Lund University, Jan Waldenströms gata 35, Building 91, Skåne University Hospital, SE-20502 Malmö, Sweden.
    Kurbasic, Azra
    Franks, Paul W.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine. Genetic and Molecular Epidemiology Unit, Department of Clinical Sciences, Clinical Research Centre, Lund University, Jan Waldenströms gata 35, Building 91, Skåne University Hospital, SE-20502 Malmö, Sweden; Department of Nutrition, Harvard T. H. Chan School of Public Health, Boston, MA, USA.
    The heritable basis of gene-environment interactions in cardiometabolic traits2017In: Diabetologia, ISSN 0012-186X, E-ISSN 1432-0428, Vol. 60, no 3, 442-452 p.Article in journal (Refereed)
    Abstract [en]

    Aims/hypothesis Little is known about the heritable basis of gene-environment interactions in humans. We therefore screened multiple cardiometabolic traits to assess the probability that they are influenced by genotype-environment interactions.

    Methods Fourteen established environmental risk exposures and 11 cardiometabolic traits were analysed in the VIKING study, a cohort of 16,430 Swedish adults from 1682 extended pedigrees with available detailed genealogical, phenotypic and demographic information, using a maximum likelihood variance decomposition method in Sequential Oligogenic Linkage Analysis Routines software.

    Results All cardiometabolic traits had statistically significant heritability estimates, with narrow-sense heritabilities (h (2)) ranging from 24% to 47%. Genotype-environment interactions were detected for age and sex (for the majority of traits), physical activity (for triacylglycerols, 2 h glucose and diastolic BP), smoking (for weight), alcohol intake (for weight, BMI and 2 h glucose) and diet pattern (for weight, BMI, glycaemic traits and systolic BP). Genotype-age interactions for weight and systolic BP, genotype-sex interactions for BMI and triacylglycerols and genotype-alcohol intake interactions for weight remained significant after multiple test correction.

    Conclusion/hypothesis Age, sex and alcohol intake are likely to be major modifiers of genetic effects for a range of cardiometabolic traits. This information may prove valuable for studies that seek to identify specific loci that modify the effects of lifestyle in cardiometabolic disease.

  • de Santiago Ochoa, Juan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity.
    Demand response for renewable energy integration2017Conference paper (Other academic)
    Abstract [en]

    Renewable energy sources are intermittent and not dispatchable. The increase in wind and solar power creates new demands in the regulation at different time scales. Here, two projects on demand response developed at Uppsala University are presented. Short term mismatches between production and consumption leads to deviations in the grid frequency. The contribution of cooling appliances in the frequency regulation has been studied. Electric Energy Time-shift requires some sort of energy storage with slow dynamics. HSLU in Switzerland is investigating the use of electric water heaters as a thermal energy storage system to balance wind power production. Uppsala University contributed with the analysis of hot water consumption profiles for system sizing.

  • Alghamdi, Fayiq
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Computing Science. Al-Baha University, Department of Education.
    Why do female students choose to study CS in the Kingdom of Saudi Arabia?2017In: Proc. 5th International Conference on Learning and Teaching in Computing and Engineering, IEEE Computer Society, 2017Conference paper (Other academic)
  • Public defence: 2017-06-09 10:00 Hörsal E2, Stockholm
    Magnusson, Jesper
    KTH, School of Electrical Engineering (EES), Electromagnetic Engineering.
    Studies on Current Commutation in Hybrid DC-breakers2017Doctoral thesis, monograph (Other academic)
    Abstract [en]

    Compared to conventional AC-circuit breakers, a DC-breaker has to act fast and force the current down to zero. Many different DC-breaker topologies are available, and this thesis is focused on the hybrid DC-breaker comprising a mechanical switch and high power semiconductors.

    The main part of this thesis is focused on the current commutations in the hybrid DC-breaker. The two current commutations: from the mechanical switch to the semiconductor branch, and from the semiconductor to the metal oxide varistor, have completely different characteristics. When the mechanical switch opens, the metallic contacts separate and an electric arc is formed. As the voltage across the arc is higher than the voltage across the semiconductors, the current is pushed over to the semiconductor branch. The undesired stray inductance in the loop limits the current derivative and slows down the commutation. As the contacts keep separating, the arc voltage increases and eventually all current is conducted by the semiconductor and the arc ceases.

    For a hybrid DC-breaker, the worst case is a solid ground fault, as the fast rising current results in high current levels and makes the commutation from the mechanical switch to the semiconductor both difficult and slow. However, the fast rise of the current can be used to enhance the commutation by using coupled inductors in the two parallel branches. When the fault current rises in the semiconductor branch, the mutual coupling of the inductors causes the current in the mechanical switch to decrease and helps the commutation. The result is that the commutation time decreases with decreasing fault impedance, and makes the solid ground fault easier to handle.

    The commutation from the semiconductor to the metal oxide varistor is controlled by the turn-off of the semiconductor. When the semiconductor is turned off, it pulls the current down to zero with a rather constant current derivative regardless of the surrounding circuit and the system current is taken over by the metal oxide varistor. Hence, any inductance in the commutation loop will result in an over-voltage proportional to this inductance on top of the varistor voltage. By connecting a smaller metal oxide varistor, as a snubber, close to the semiconductor, the over-voltage can be controlled and the commutation from the snubber to the metal oxide varistor will be driven by the voltage difference between the two varistors.

    It is shown that for a 12 kV DC-system, a possible design of the mechanical switch in the hybrid DC-breaker comprises two contact gaps in series and opens with a velocity of 11 m/s. It has been experimentally verified that when starting the commutation at 4 kA, the commutation takes less than 700 us and is over before the switch has opened 1 mm.

    The thesis also contains proposed designs for an 80 kV DC-breaker that can be used as a modular solution for higher system voltages. For this higher voltage, the design will be a choice of the combination between the number of contact gaps in series and the opening velocity of the mechanical switch.

  • Public defence: 2017-06-09 09:15 Rosénsalen, Uppsala
    Gunnarsdóttir, Jóhanna
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health, Obstetrics and Gynaecology.
    Epidemiological Studies of Preeclampsia: Maternal & Offspring Perspectives 2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Preeclampsia is a placental-related disorder characterized by generalized endothelial activation. Vascular predisposition is associated with the occurrence of preeclampsia and the recurrence risk is substantial. Onset of preeclampsia is preceded by placental hypo-perfusion, and placental over-production of vasoconstrictive agents might explain symptoms such as hypertension and proteinuria. Preeclampsia is associated with the birth of small-for-gestational-age (SGA) infants. The trajectory of postnatal growth in SGA-born children is described as catch-up, but it is unclear whether prenatal preeclampsia is independently associated with postnatal growth.

    The objectives were: firstly, to study the association between partner change and prior miscarriages on the occurrence of preeclampsia and SGA; secondly, to study postnatal growth in children prenatally exposed to preeclampsia; and thirdly, to address the association between blood pressure (BP) changes during pregnancy and risks of preeclampsia and SGA.

    Population-based cohort studies were performed with information from the following registers: Swedish Medical Birth Register, Uppsala Mother and Child Database and Stockholm-Gotland Obstetric Database. Associations were estimated with logistic and linear regression analyses, with adjustments for maternal characteristics, including body mass index, pre-gestational diseases and socioeconomic factors.

    The results were, firstly, that partner change was associated with preeclampsia and SGA birth in the second pregnancy but depended on the outcome of the first pregnancy, and that a history of recurrent miscarriages was associated with increased risks of preeclampsia and SGA. Secondly, prenatal exposure to preeclampsia was associated with increased offspring growth in height during the first five years. This association was also seen in children born with normal birth weight for gestational age. Thirdly, pre-hypertension in late gestation and elevated diastolic BP from early to mid-gestation were both associated with SGA birth. Further, women with pre-hypertension in early gestation without lowered diastolic BP until mid-gestation seemed to represent a risk group for preeclampsia.

    To conclude, the importance of previous pregnancy outcomes in the antenatal risk evaluation was highlighted. Secondly, the results imply that postnatal growth trajectory is related to maternal preeclampsia, in addition to SGA. Thirdly, the association between BP changes within a normal range and SGA may challenge the clinical cut-off for hypertension in pregnancy.

  • Justice, Anne E
    et al.
    Winkler, Thomas W
    Feitosa, Mary F
    Graff, Misa
    Fisher, Virginia A
    Young, Kristin
    Barata, Llilda
    Deng, Xuan
    Czajkowski, Jacek
    Hadley, David
    Ngwa, Julius S
    Ahluwalia, Tarunveer S
    Chu, Audrey Y
    Heard-Costa, Nancy L
    Lim, Elise
    Perez, Jeremiah
    Eicher, John D
    Kutalik, Zoltan
    Xue, Luting
    Mahajan, Anubha
    Renström, Frida
    Umeå University, Faculty of Medicine, Department of Biobank Research.
    Wu, Joseph
    Qi, Qibin
    Ahmad, Shafqat
    Alfred, Tamuno
    Amin, Najaf
    Bielak, Lawrence F
    Bonnefond, Amelie
    Bragg, Jennifer
    Cadby, Gemma
    Chittani, Martina
    Coggeshall, Scott
    Corre, Tanguy
    Direk, Nese
    Eriksson, Joel
    Fischer, Krista
    Gorski, Mathias
    Neergaard Harder, Marie
    Horikoshi, Momoko
    Huang, Tao
    Huffman, Jennifer E
    Jackson, Anne U
    Justesen, Johanne Marie
    Kanoni, Stavroula
    Kinnunen, Leena
    Kleber, Marcus E
    Komulainen, Pirjo
    Kumari, Meena
    Lim, Unhee
    Luan, Jian'an
    Lyytikainen, Leo-Pekka
    Mangino, Massimo
    Manichaikul, Ani
    Marten, Jonathan
    Middelberg, Rita P S
    Muller-Nurasyid, Martina
    Navarro, Pau
    Perusse, Louis
    Pervjakova, Natalia
    Sarti, Cinzia
    Smith, Albert Vernon
    Smith, Jennifer A
    Stancakova, Alena
    Strawbridge, Rona J
    Stringham, Heather M
    Sung, Yun Ju
    Tanaka, Toshiko
    Teumer, Alexander
    Trompet, Stella
    van der Laan, Sander W
    van der Most, Peter J
    Van Vliet-Ostaptchouk, Jana V
    Vedantam, Sailaja L
    Verweij, Niek
    Vink, Jacqueline M
    Vitart, Veronique
    Wu, Ying
    Yengo, Loic
    Zhang, Weihua
    Hua Zhao, Jing
    Zimmermann, Martina E
    Zubair, Niha
    Abecasis, Goncalo R
    Adair, Linda S
    Afaq, Saima
    Afzal, Uzma
    Bakker, Stephan J L
    Bartz, Traci M
    Beilby, John
    Bergman, Richard N
    Bergmann, Sven
    Biffar, Reiner
    Blangero, John
    Boerwinkle, Eric
    Bonnycastle, Lori L
    Bottinger, Erwin
    Braga, Daniele
    Buckley, Brendan M
    Buyske, Steve
    Campbell, Harry
    Chambers, John C
    Collins, Francis S
    Curran, Joanne E
    de Borst, Gert J
    de Craen, Anton J M
    de Geus, Eco J C
    Dedoussis, George
    Delgado, Graciela E
    den Ruijter, Hester M
    Eiriksdottir, Gudny
    Eriksson, Anna L
    Esko, Tonu
    Faul, Jessica D
    Ford, Ian
    Forrester, Terrence
    Gertow, Karl
    Gigante, Bruna
    Glorioso, Nicola
    Gong, Jian
    Grallert, Harald
    Grammer, Tanja B
    Grarup, Niels
    Haitjema, Saskia
    Hallmans, Göran
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Nutritional Research.
    Hamsten, Anders
    Hansen, Torben
    Harris, Tamara B
    Hartman, Catharina A
    Hassinen, Maija
    Hastie, Nicholas D
    Heath, Andrew C
    Hernandez, Dena
    Hindorff, Lucia
    Hocking, Lynne J
    Hollensted, Mette
    Holmen, Oddgeir L
    Homuth, Georg
    Jan Hottenga, Jouke
    Huang, Jie
    Hung, Joseph
    Hutri-Kahonen, Nina
    Ingelsson, Erik
    James, Alan L
    Jansson, John-Olov
    Jarvelin, Marjo-Riitta
    Jhun, Min A
    Jorgensen, Marit E
    Juonala, Markus
    Kahonen, Mika
    Karlsson, Magnus
    Koistinen, Heikki A
    Kolcic, Ivana
    Kolovou, Genovefa
    Kooperberg, Charles
    Kramer, Bernhard K
    Kuusisto, Johanna
    Kvaloy, Kirsti
    Lakka, Timo A
    Langenberg, Claudia
    Launer, Lenore J
    Leander, Karin
    Lee, Nanette R
    Lind, Lars
    Lindgren, Cecilia M
    Linneberg, Allan
    Lobbens, Stephane
    Loh, Marie
    Lorentzon, Mattias
    Luben, Robert
    Lubke, Gitta
    Ludolph-Donislawski, Anja
    Lupoli, Sara
    Madden, Pamela A F
    Mannikko, Reija
    Marques-Vidal, Pedro
    Martin, Nicholas G
    McKenzie, Colin A
    McKnight, Barbara
    Mellstrom, Dan
    Menni, Cristina
    Montgomery, Grant W
    Musk, Aw Bill
    Narisu, Narisu
    Nauck, Matthias
    Nolte, Ilja M
    Oldehinkel, Albertine J
    Olden, Matthias
    Ong, Ken K
    Padmanabhan, Sandosh
    Peyser, Patricia A
    Pisinger, Charlotta
    Porteous, David J
    Raitakari, Olli T
    Rankinen, Tuomo
    Rao, D C
    Rasmussen-Torvik, Laura J
    Rawal, Rajesh
    Rice, Treva
    Ridker, Paul M
    Rose, Lynda M
    Bien, Stephanie A
    Rudan, Igor
    Sanna, Serena
    Sarzynski, Mark A
    Sattar, Naveed
    Savonen, Kai
    Schlessinger, David
    Scholtens, Salome
    Schurmann, Claudia
    Scott, Robert A
    Sennblad, Bengt
    Siemelink, Marten A
    Silbernagel, Gunther
    Slagboom, P Eline
    Snieder, Harold
    Staessen, Jan A
    Stott, David J
    Swertz, Morris A
    Swift, Amy J
    Taylor, Kent D
    Tayo, Bamidele O
    Thorand, Barbara
    Thuillier, Dorothee
    Tuomilehto, Jaakko
    Uitterlinden, Andre G
    Vandenput, Liesbeth
    Vohl, Marie-Claude
    Volzke, Henry
    Vonk, Judith M
    Waeber, Gerard
    Waldenberger, Melanie
    Westendorp, R G J
    Wild, Sarah
    Willemsen, Gonneke
    Wolffenbuttel, Bruce H R
    Wong, Andrew
    Wright, Alan F
    Zhao, Wei
    Zillikens, M Carola
    Baldassarre, Damiano
    Balkau, Beverley
    Bandinelli, Stefania
    Boger, Carsten A
    Boomsma, Dorret I
    Bouchard, Claude
    Bruinenberg, Marcel
    Chasman, Daniel I
    Chen, Yii-DerIda
    Chines, Peter S
    Cooper, Richard S
    Cucca, Francesco
    Cusi, Daniele
    Faire, Ulf de
    Ferrucci, Luigi
    Franks, Paul W
    Froguel, Philippe
    Gordon-Larsen, Penny
    Grabe, Hans-Jorgen
    Gudnason, Vilmundur
    Haiman, Christopher A
    Hayward, Caroline
    Hveem, Kristian
    Johnson, Andrew D
    Wouter Jukema, J
    Kardia, Sharon L R
    Kivimaki, Mika
    Kooner, Jaspal S
    Kuh, Diana
    Laakso, Markku
    Lehtimaki, Terho
    Marchand, Loic Le
    Marz, Winfried
    McCarthy, Mark I
    Metspalu, Andres
    Morris, Andrew P
    Ohlsson, Claes
    Palmer, Lyle J
    Pasterkamp, Gerard
    Pedersen, Oluf
    Peters, Annette
    Peters, Ulrike
    Polasek, Ozren
    Psaty, Bruce M
    Qi, Lu
    Rauramaa, Rainer
    Smith, Blair H
    Sorensen, Thorkild I A
    Strauch, Konstantin
    Tiemeier, Henning
    Tremoli, Elena
    van der Harst, Pim
    Vestergaard, Henrik
    Vollenweider, Peter
    Wareham, Nicholas J
    Weir, David R
    Whitfield, John B
    Wilson, James F
    Tyrrell, Jessica
    Frayling, Timothy M
    Barroso, Ines
    Boehnke, Michael
    Deloukas, Panagiotis
    Fox, Caroline S
    Hirschhorn, Joel N
    Hunter, David J
    Spector, Tim D
    Strachan, David P
    van Duijn, Cornelia M
    Heid, Iris M
    Mohlke, Karen L
    Marchini, Jonathan
    Loos, Ruth J F
    Kilpelainen, Tuomas O
    Liu, Ching-Ti
    Borecki, Ingrid B
    North, Kari E
    Cupples, L Adrienne
    Genome-wide meta-analysis of 241,258 adults accounting for smoking behaviour identifies novel loci for obesity traits2017In: Nature Communications, ISSN 2041-1723, E-ISSN 2041-1723, Vol. 8, 14977-14977 p.Article in journal (Refereed)
    Abstract [en]

    Few genome-wide association studies (GWAS) account for environmental exposures, like smoking, potentially impacting the overall trait variance when investigating the genetic contribution to obesity-related traits. Here, we use GWAS data from 51,080 current smokers and 190,178 nonsmokers (87% European descent) to identify loci influencing BMI and central adiposity, measured as waist circumference and waist-to-hip ratio both adjusted for BMI. We identify 23 novel genetic loci, and 9 loci with convincing evidence of gene-smoking interaction (GxSMK) on obesity-related traits. We show consistent direction of effect for all identified loci and significance for 18 novel and for 5 interaction loci in an independent study sample. These loci highlight novel biological functions, including response to oxidative stress, addictive behaviour, and regulatory functions emphasizing the importance of accounting for environment in genetic analyses. Our results suggest that tobacco smoking may alter the genetic susceptibility to overall adiposity and body fat distribution.

  • Public defence: 2017-06-21 10:30 21A342 (Eva Erikssonsalen), Karlstad
    Nasim, Robayet
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Cost- and Performance-Aware Resource Management in Cloud Infrastructures2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    High availability, cost effectiveness and ease of application deployment have accelerated the adoption rate of cloud computing. This fast proliferation of cloud computing promotes the rapid development of large-scale infrastructures. However, large cloud datacenters (DCs) require infrastructure, design, deployment, scalability and reliability and need better management techniques to achieve sustainable design benefits. Resources inside cloud infrastructures often operate at low utilization, rarely exceeding 20-30%, which increases the operational cost significantly, especially due to energy consumption. To reduce operational cost without affecting quality of service (QoS) requirements, cloud applications should be allocated just enough resources to minimize their completion time or to maximize utilization. 

    The focus of this thesis is to enable resource-efficient and performance-aware cloud infrastructures by addressing above mentioned cost and performance related challenges. In particular, we propose algorithms, techniques, and deployment strategies for improving the dynamic allocation of virtual machines (VMs) into physical machines (PMs). 

    For minimizing the operational cost, we mainly focus on optimizing energy consumption of PMs by applying dynamic VM consolidation methods. To make VM consolidation techniques more efficient, we propose to utilize multiple paths to spread traffic and deploy recent queue management schemes which can maximize network resource utilization and reduce both downtime and migration time for live migration techniques. In addition, a dynamic resource allocation scheme is presented to distribute workloads among geographically dispersed DCs considering their location based time varying costs due to e.g. carbon emission or bandwidth provision. For optimizing performance level objectives, we focus on interference among applications contending in shared resources and propose a novel VM consolidation scheme considering sensitivity of the VMs to their demanded resources. Further, to investigate the impact of uncertain parameters on cloud resource allocation and applications’ QoS such as unpredictable variations in demand, we develop an optimization model based on the theory of robust optimization. Furthermore, in order to handle the scalability issues in the context of large scale infrastructures, a robust and fast Tabu Search algorithm is designed and evaluated.

  • Public defence: 2017-06-02 13:00 Hus H, sal Hb 116, Jönköping University, Jönköping
    Anderström, Helena
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Centre for the Studies of Social Sciences Didactics.
    Lärares samtal om etik: Sociala representationer av etikundervisning på mellanstadiet inom ramen för de samhällsorienterande ämnena2017Licentiate thesis, monograph (Other academic)
    Abstract [en]

    This study draws attention to how teachers view and reason about ethics education in social studies. Based on the Social representation theory, the study aim to answer questions about the content and themes which are expressed in the teachers' conversations about ethics education. The study also wants to emphasize the communicative resources used by participants when they create a common understanding of ethics education.

    The study's empirical data consists of six focus groups interviews with teachers working with student in school year 4-6. Teachers in three teams (a total of 13 teachers) met at two occasions to talk about ethics education in social studies.

    The result from the analysis is presented in three parts. The first part draws attention to teachers' social representations of ethics education in social studies. Four social representations were found and they consist of teachers' ideas about content, methods and strategies, and the purpose and goals and difficulties in ethics education. The second part shows that the teachers express three social representations of how ethics education is related to, religious education, social studies and the school's overall mission. The analysis shows that ethics education is an important part of the religious education but also other subjects in social studies and the school's overall mission. The third part draws attention to the communicative resources that teachers use to create a common understanding of ethics education. Examples of communicative resources used in the conversations is teaching materials, national tests, the curriculum and their own teacher education.

  • Schmidt, Bernard
    et al.
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Wang, Lihui
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre. KTH Royal Institute of Technology, Stockholm, Sweden.
    Galar, Diego
    University of Skövde, School of Engineering Science. University of Skövde, The Virtual Systems Research Centre.
    Semantic Framework for Predictive Maintenance in a Cloud Environment2017In: 10th CIRP Conference on Intelligent Computation in Manufacturing Engineering - CIRP ICME '16 / [ed] Roberto Teti and Doriana M D'Addona, Elsevier, 2017, Vol. 62, 583-588 p.Conference paper (Refereed)
    Abstract [en]

    Proper maintenance of manufacturing equipment is crucial to ensure productivity and product quality. To improve maintenance decision support, and enable prediction-as-a-service there is a need to provide the context required to differentiate between process and machine degradation. Correlating machine conditions with process and inspection data involves data integration of different types such as condition monitoring, inspection and process data. Moreover, data from a variety of sources can appear in different formats and with different sampling rates. This paper highlights those challenges and presents a semantic framework for data collection, synthesis and knowledge sharing in a Cloud environment for predictive maintenance.

  • Public defence: 2017-06-12 13:00 A1:111a, Uppsala
    Holmgren, Benjamin T.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Cell and Molecular Biology, Microbiology.
    Connecting Systemic RNAi to the Endomembrane System in Caenorhabditis elegans2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    RNA interference (RNAi) is a gene regulation mechanism conserved among eukaryotes. To silence gene expression, RNAi relies on a short single-stranded guide RNA to steer the RNA-induced Silencing Complex (RISC) to mRNAs with guide strand-complementary sequences. RNAi is a highly membrane-associated process. The RISC complex is likely loaded at the rough Endoplasmic Reticulum, where it can bind to and degrade mRNAs. Components of the RISC complex also colocalize to late endosomes, and the efficiency of RNAi-mediated silencing is affected by changes in late endosome to lysosome fusion. RNAi can be systemic and inherited, effecting gene silencing in distal tissues and in the offspring.

    In this thesis, the model organism Caenorhabditis elegans was used to identify and characterize factors connecting systemic and inherited RNAi to the endomembrane system. We identify two SNARE proteins, SEC-22 and SYX-6, that both act as negative regulators of RNAi. SNAREs are necessary for vesicle fusion. Both SEC-22 and SYX-6 localize to late endosomes, and both interact with systemic RNAi protein SID-5 in a yeast two-hybrid (Y2H) screen. We find that in addition to its function in systemic RNAi, SID-5 is required for proper maturation of late endosomes. Furthermore, we identify the putative RNA-binding protein C12D8.1 as a novel regulator of RNAi inheritance. Mutant C12D8.1 animals will have enhanced inheritance of RNAi silencing, which negatively affects the ability of the progeny to silence new targets using RNAi. Finally, we describe a novel, object-based method for estimating significance in colocalization studies. This method helped us describe and quantify spatial relations between fluorophore-labeled proteins in situations where such analyses would otherwise be impossible.

    In conclusion, the work presented here further elucidates the connection between cellular RNAi, the endomembrane system, and the outside world.

  • Public defence: 2017-06-09 10:00 M311, Stockholm
    Ratanathavorn, Wallop
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Welding Technology.
    Dissimilar joining of aluminium to ultra-high strength steels by friction stir welding2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Multi-material structures are increasingly used in vehicle bodies to reduce weight of cars. The use of these lightweight structures is driven by requirements to improve fuel economy and reduce CO2 emissions. The automotive industry has replaced conventional steel components by lighter metals such as aluminium alloy. This is done together with cutting weight of structures using more advanced strength steels. However, sound joining is still difficult to achieve due to differences in chemical and thermal properties.

     

    This research aims to develop a new innovative welding technique for joining aluminium alloy to ultra-high strength steels. The technique is based on friction stir welding process while the non-consumable tool is made of an ordinary tool steel. Welding was done by penetrating the rotating tool from the aluminium side without penetrating into the steel surface. One grade of Al-Mg aluminium alloy was welded to ultra-high strength steels under lap joint configuration. Different types of steel surface coatings including uncoated, hot-dipped galvanised and electrogalvanised coating have been studied in order to investigate the influence of zinc on the joint properties. The correlation among welding parameters, microstructures, intermetallic formation and mechanical properties are demonstrated in this thesis.  Results have shown that friction stir welding can deliver fully strong joints between aluminium alloy and ultra-high strength steels. Two intermetallic phases, Al5Fe2 and Al13Fe4, were formed at the interface of Al to Fe regardless of surface coating conditions. The presence of zinc can improve joint strength especially at low heat input welding due to an increased atomic bonding at Al-Fe interface. The formation of intermetallic phases as well as their characteristics has been demonstrated in this thesis. The proposed welding mechanisms are given based on metallography investigations and related literature.

  • Public defence: 2017-06-15 13:00 Kollegiesalen, Stockholm
    Liljeblad, Elisabet
    KTH, School of Electrical Engineering (EES), Space and Plasma Physics.
    Structures and processes in the Mercury magnetosphere2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The mechanisms involved in the transfer of mass and energy from the solar wind to any planetary magnetosphere is considered an important topic in space physics. With the use of the Mercury spacecraft MESSENGER's data, it has been possible to study these processes in an environment different, yet similar, to Earth's. These data have resulted in new knowledge advancing not only the extraterrestrial space plasma research, but also the general space physics field.

     

    This thesis aims to investigate mechanisms for the transfer of mass and energy into Mercury’s magnetosphere, and magnetospheric regions affected by, and processes directly driven by, these. The work includes the Kelvin-Helmholtz instability (KHI) at the magnetopause, which is one of the main drivers for mass and energy transfer on Earth, the low-latitude boundary layer (LLBL), which is in direct connection to the magnetopause and proposed to be affected by the KHI, magnetospheric ultra-low frequency (ULF) waves driven by the KHI, and isolated magnetic field structures in the magnetosheath as possible analogues to the Earth magnetosheath plasmoids and jets.

     

    Kelvin-Helmholtz waves (KHW) and the LLBL are identified and characterized. The KHWs are observed almost exclusively on the duskside magnetopause, something that has not been observed on Earth. In contrast, the LLBL shows an opposite asymmetry. Results suggest that the KHI and LLBL are connected, possibly by the LLBL creating the asymmetry observed for the KHWs.

     

    Isolated changes of the total magnetic field strength in the magnetosheath are identified. The similar properties of the solar wind and magnetosheath negative magnetic field structures suggest that they are analogues to diamagnetic plasmoids found on Earth. No clear analogues to paramagnetic plasmoids are found.  

     

    Distinct magnetospheric ULF wave signatures are detected frequently in close connection to KHWs. Results from the polarization analysis on the dayside ULF waves indicate that the majority of these are most probably driven by the KHI. In general, likely KHI driven ULF waves are observed frequently in the Hermean magnetosphere. 

    Although similar in many aspects, Mercury and Earth show fundamental differences in processes and structures, making Mercury a highly interesting planet to study to increase our knowledge of Earth-like planets.

  • Public defence: 2017-06-09 13:00 M3, Stockholm
    Taliotis, Constantinos
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy Systems Analysis.
    Large scale renewable energy deployment - Insights offered by long-term energy models from selected case studies2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The United Nations’ Sustainable Development Goal 7 (SDG7) of Agenda 2030 calls for an increase in the use of renewable energy sources, among other targets. The percentage of fossil fuel-fired thermal generation for electricity is increasingly being reduced as renewable energy technologies (RET) advance in cost-competitiveness, and as greenhouse gas and industrial air pollutant emission limits become more stringent. In certain cases, renewable energy contributes to energy security by improving a nation’s trade balance, since local resources are harnessed and imports are reduced. RET investments are becoming more frequent gaining a sizeable share in the electric power mix of numerous countries.

    However, RET is affected by existing fossil fuel-fired electricity generation, especially in countries that have domestic reserves. While coal may be dirty, others such as natural gas provide multiple benefits, presenting a challenge to renewables. Additionally, RET endowment varies for each geographical location. This often does not correspond to the location of major electricity demand centers.  Therefore, large scale RET adoption and integration becomes logistically more cumbersome, as it necessitates existence of a developed grid network.

    Utilizing a series of analyses in two different settings – Africa and Cyprus – this thesis draws insights on RET growth policy and the level of technology representation in long term energy models. In order to capture specific challenges of RET integration, enhancements in traditional long-term energy system models are called for and carried out.

     The case of Africa is used to assess adoption of RET under various trade scenarios. It is home to some of the world’s greatest RET resource potential and the single largest potential RET project, Grand Inga.  While, the island of Cyprus has goals of introducing large percentages of RET into its electric power mix. Each have important idiosyncrasies which are reflected in the analysis. On the one hand, natural gas competes with RET in Cyprus and forms a key transition fuel away from oil. On the other hand, lack of cross-border interconnectors limit RET project development across Africa.

  • Public defence: 2017-06-13 10:15 Hus O, sal 125, Halmstad
    Luthfa Karim, Sabrina
    Halmstad University, School of Business, Engineering and Science.
    The Uncertainty-Embedded Innovation Process: A study of how uncertainty emerges in the innovation process and of how firms address that to create novelty2017Doctoral thesis, monograph (Other academic)
    Abstract [en]

    Despite much discussion in the literature of uncertainties in relation to the innovation process, there is little knowledge of how they emerge in this process. This thesis accordingly aims to understand how uncertainty emerges in the innovation process and how firms address that uncertainty to create novelty from the process. Uncertainty is embedded in the innovation process (Jalonen, 2012), which implies that it is not only a factor affecting the innovation process but also an outcome of the process itself. To fulfil the purpose of this study, it is important to understand how the innovation process unfolds over time. It is well established that innovation is a process of recombining resources (Schumpeter, 1934) through the performing and linking of certain activities in sequence (Richardson, 1972; Dubois, 1994; Bankvall, 2011) by various actors (i.e., firms and organizations) in a network context (Håkansson and Olsen, 2012; Lampela, 2012; Love and Roper, 2001; Pittaway et al., 2004; Powell et al., 1996). To fulfil the purpose of this study, the following research question has been asked: How and why do actors undertake and link resource recombination activities in a network context, thereby managing uncertainties in the innovation process?

    The thesis investigates the innovation process in two companies. One of the companies had completed its innovation journey and the other had almost done so. The discussion gives a detailed account of: the activities these companies performed alone and jointly with their partners in a network context; the resources they exchanged with each other and recombined to bring new solutions to the market; the uncertainties created in the process of recombining the resources; and the activities they undertook in response to address these uncertainties. The innovation process in the case companies is analysed in light of a conceptual model developed here based on Dubois’ (1994) “end product related activity structure model”, Håkansson’s (1987) “ARA model/network model”, and Goldratt’s (1997) “critical chain concept”.

    This study identifies the conditions under which uncertainties emerged in the innovation process in the studied companies. One of the significant conditions was resource unavailability, which was caused by actors’ reluctance to share resources, prohibition by government policy, and the resources’ own conflicting conditions and internal resistance (Håkansson and Snehota, 1995; Håkansson and Waluszewski, 2002; Waluszewski, 2004). Resource unavailability caused inertial and repetitive activities and delayed the process of producing an outcome, having such an impact on the activities under the condition of path dependency (Arthur, 1994; David, 2000). Another observed condition was the actors’ lack of knowledge of resource combination (Jalonen, 2011).

    A type of uncertainty that seriously affects the outcome of the innovation process is the activity void, a situation in which no activity is taking place. Activity voids are created from resource unavailability either by an actor’s reluctance to share resources or by the outcome of combining conflicting resource properties.

    The outcome of the innovation process is therefore affected by the key actor’s attempt to reduce the activity void by making compromises at the three levels, interplay among which construct the process, i.e., actors, resources, and activities. To manage uncertainties, managers make many compromises when they perform and link various activities. Although the underlying motivation for making compromises is rational, it is boundedly rational (Simon, 1957) because by making compromises, managers forego expectations of having all the properties or of being able to plan, undertake, and link activities as intended. This study also reveals that sometimes actors prefer not to make compromises despite knowing that this might cost a great deal. Accordingly, the findings suggest that compromises made within a working relationship allow actors to produce novelty without deviating from the desired path by ensuring access to resources and partners’ abilities. On the contrary, compromises not made in the relationship can threaten actors’ ability to produce the desired novelty, as the exchange of partners’ resources and abilities is hindered in a poor relationship. Compromises made in resource configuration and activities threaten actors’ ability to produce the desired novelty by limiting their choices, while compromises not made in resource configuration and activities allow actors to produce the desired novelty without deviation.

  • Wallström, Åsa
    et al.
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Business Administration and Industrial Engineering.
    Ek Styvén, Maria
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Business Administration and Industrial Engineering.
    Engström, Anne
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Business Administration and Industrial Engineering.
    Salehi-Sangari, Esmail
    Kungliga tekniska högskolan.
    Kundens kanal(k)val i detaljhandeln: Paradigmskifte i konsumenternas köpbeteenden2017Report (Other (popular science, discussion, etc.))
  • Wallström, Åsa
    et al.
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Business Administration and Industrial Engineering.
    Ek Styvén, Maria
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Business Administration and Industrial Engineering.
    Engström, Anne
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Business Administration and Industrial Engineering.
    Foster, Tim
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Business Administration and Industrial Engineering.
    Morgondagens turist: Hur ska besöksnäringen bemöta e-generationen?2016Report (Other (popular science, discussion, etc.))
  • Public defence: 2017-06-15 14:00 M311, Stockholm
    Li, Yujiang
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Computer Systems for Design and Manufacturing.
    Architecting model driven system integration in production engineering2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    System integration is a key enabler to maximize information value in an engineering context. The valuable information is normally represented by information models which play a decisive role in the implementation of system integration. The information models are designed to efficiently and effectively capture, process and communicate information among different functional and business units. However, use of the information models in implementing system integration is challenged by insufficient support from current settings of modeling architectures. This situation calls for new strategies to ease the use of information models.

    To address this challenge, this study presents a new twofold solution: Model driven system integration. It includes 1) a modeling architecture to guide the development of information models and 2) an integrated implementation process to guide the use of information models. Thus, this work improves practical applicability of an information model in its entire modeling lifecycle.

    The results contribute not only to the performance of modeling practices but also to improved understanding of information modeling in system integration. Implementation contexts and implementation models are introduced to develop an implementation-oriented modeling architecture. Further, the potential of information models as a knowledge base to sup-port implementation practices is identified.

    To concretely discuss behaviors and structures of information models, this study adopts ISO 10303 and the related standards as major references of existing information models.

    Case studies on model driven system integration validate this research in scenarios concerning kinematic modeling, kinematic error modeling, cutting tools classification and product catalogue modeling. Model driven system integration exhibits high efficiency in implementation, enhanced interoperability and increased value of information models.

  • Public defence: 2017-06-15 10:00 Q2, Stockholm
    Bleiker, Simon J.
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    Heterogeneous 3D Integration and Packaging Technologies for Nano-Electromechanical Systems2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Three-dimensional (3D) integration of micro- and nano-electromechanical systems (MEMS/NEMS) with integrated circuits (ICs) is an emerging technology that offers great advantages over conventional state-of-the-art microelectronics. MEMS and NEMS are most commonly employed as sensor and actuator components that enable a vast array of functionalities typically not attainable by conventional ICs. 3D integration of NEMS and ICs also contributes to more compact device footprints, improves device performance, and lowers the power consumption. Therefore, 3D integration of NEMS and ICs has been proposed as a promising solution to the end of Moore’s law, i.e. the slowing advancement of complementary metal-oxide-semiconductor (CMOS) technology.In this Ph.D. thesis, I propose a comprehensive fabrication methodology for heterogeneous 3D integration of NEM devices directly on top of CMOS circuits. In heterogeneous integration, the NEMS and CMOS components are fully or partially fabricated on separate substrates and subsequently merged into one. This enables process flexibility for the NEMS components while maintaining full compatibility with standard CMOS fabrication. The first part of this thesis presents an adhesive wafer bonding method using ultra-thin intermediate bonding layers which is utilized for merging the NEMS components with the CMOS substrate. In the second part, a novel NEM switch concept is introduced and the performance of CMOS-integrated NEM switch circuits for logic and computation applications is discussed. The third part examines two different packaging approaches for integrated MEMS and NEMS devices with either hermetic vacuum cavities or low-cost glass lids for optical applications. Finally, a novel fabrication approach for through silicon vias (TSVs) by magnetic assembly is presented, which is used to establish an electrical connection from the packaged devices to the outside world.

  • Public defence: 2017-06-15 09:15 FA32, Stockholm
    Liljestrand, Charlotte
    KTH, School of Engineering Sciences (SCI), Applied Physics, Laser Physics.
    Advanced nano- and microdomain engineering of Rb-doped KTiOPO4 for nonlinear optical applications2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Fine-pitch ferroelectric domain gratings are extensively used for generation of light in the visible and near-infrared spectral regions through quasi-phase matched (QPM) frequency conversion. Sub-μm QPM devices enables demonstration of nonlinear optics with counterpropagating waves, a field of nonlinear optics which remains sparsely explored due to the difficulty of fabricatinghigh quality gratings.

    In recent years, bulk Rb-doped KTiOPO4 (RKTP) has emerged as a highly promising nonlinear materials for fabrication of fine-pitch QPM devices through periodic electric-field poling. RKTP possesses large optical nonlinearity and high resistance to optical damage, while demonstrating improved material homogeneity and lower ionic conductivity than its isomorphs, which are important features for poling. Although fine-pitch QPM gratings, as well as large aperture QPM devices, have been demonstrated, fabrication of sub-μm high quality QPM devices remains a challenge.

    The primary aim of this research was to develop a reliable method to fabricate high-quality sub-μm periodically poled RKTP crystals (PPRKTP) and exploit them in novel optical applications. For this purpose, a novel poling method was developed. It was based on periodic modulation of the coercive field through ion exchange, where K+ ions are exchanged with Rb+ in the crystal, to modulate the coercive field and the ionic conductivity. This enables periodic poling of higher quality and with shorter period than ever before.

    High quality PPRKTP with a period of 755 nm were fabricated and used to demonstrate the first cascaded mirrorless optical parametric oscillator (MOPO), as well as the first MOPO pumped by a Q-switched laser. PPRKTP samples for blue light generation were fabricated, and second harmonic generation (SHG) was investigated with a high power 946 nm fiber laser. Up to 2 W of blue power was demonstrated for bulk samples, where the output power was limited by absorption of the SHG, leading to thermal dephasing of the devices. Laser-written waveguides were fabricated in PPRKTP for the first time, and a record high SHG power of 76 mW was obtained.

    Finally, the high-temperature stability of ferroelectric domain gratings was investigated. This is of utmost importance when a PPRKTP crystal is used as a seed for crystal growth. It was found that for charged domains walls, the domain-wall motion was highly anisotropic with rapid movement in y-direction while only small movements were observed in the x-direction of the crystal.

  • Roy, Ananya
    et al.
    Attarha, Sanaz
    Weishaupt, Holger
    Edqvist, Per-Henrik
    Swartling, Fredrik J.
    Bergqvist, Michael
    Umeå University, Faculty of Medicine, Department of Radiation Sciences.
    Siebzehnrubl, Florian A.
    Smits, Anja
    Ponten, Fredrik
    Tchougounova, Elena
    Serglycin as a potential biomarker for glioma: association of serglycin expression, extent of mast cell recruitment and glioblastoma progression2017In: OncoTarget, ISSN 1949-2553, E-ISSN 1949-2553, Vol. 8, no 15, 24815-24827 p.Article in journal (Refereed)
    Abstract [en]

    Serglycin is an intracellular proteoglycan with a unique ability to adopt highly divergent structures by glycosylation with variable types of glycosaminoglycans (GAGs) when expressed by different cell types. Serglycin is overexpressed in aggressive cancers suggesting its protumorigenic role. In this study, we explored the expression of serglycin in human glioma and its correlation with survival and immune cell infiltration. We demonstrate that serglycin is expressed in glioma and that increased expression predicts poor survival of patients. Analysis of serglycin expression in a large cohort of low-and high-grade human glioma samples reveals that its expression is grade dependent and is positively correlated with mast cell (MC) infiltration. Moreover, serglycin expression in patient-derived glioma cells is significantly increased upon MC co-culture. This is also accompanied by increased expression of CXCL12, CXCL10, as well as markers of cancer progression, including CD44, ZEB1 and vimentin. In conclusion, these findings indicate the importance of infiltrating MCs in glioma by modulating signaling cascades involving serglycin, CD44 and ZEB1. The present investigation reveals serglycin as a potential prognostic marker for glioma and demonstrates an association with the extent of MC recruitment and glioma progression, uncovering potential future therapeutic opportunities for patients.

  • Kable, Mary E.
    et al.
    Hansen, Lori M.
    Styer, Cathy M.
    Deck, Samuel L.
    Rakhimova, Olena
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Shevtsova, Anna
    Eaton, Kathryn A.
    Martin, Miriam E.
    Gideonsson, Pär
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Borén, Thomas
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Solnick, Jay V.
    Host Determinants of Expression of the Helicobacter pylori BabA Adhesin2017In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 7, 46499Article in journal (Refereed)
    Abstract [en]

    Expression of the Helicobacter pylori blood group antigen binding adhesin A (BabA) is more common in strains isolated from patients with peptic ulcer disease or gastric cancer, rather than asymptomatic colonization. Here we used mouse models to examine host determinants that affect H. pylori BabA expression. BabA expression was lost by phase variation as frequently in WT mice as in RAG2-/- mice that do not have functional B or T cells, and in MyD88-/-, TLR2-/- and TLR4-/- mice that are defective in toll like receptor signaling. The presence of other bacteria had no effect on BabA expression as shown by infection of germ free mice. Moreover, loss of BabA expression was not dependent on Le(b) expression or the capacity of BabA to bind Leb. Surprisingly, gender was the host determinant most associated with loss of BabA expression, which was maintained to a greater extent in male mice and was associated with greater bacterial load. These results suggest the possibility that loss of BabA expression is not driven by adaptive immunity or toll-like receptor signaling, and that BabA may have other, unrecognized functions in addition to serving as an adhesin that binds Le(b).

  • Nilsson, Andreas
    et al.
    Örebro University, School of Health Sciences.
    Wåhlin-Larsson, Britta
    Örebro University, School of Health Sciences.
    Kadi, Fawzi
    Örebro University, School of Health Sciences.
    Physical activity and not sedentary time per se influences on clustered metabolic risk in elderly community-dwelling women2017In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 2, no 4, e0175496Article in journal (Refereed)
  • Thienel, Matthias
    et al.
    Univ Tubingen, Inst Med Psychol & Behav Neurobiol, Otfried Muller Str 25, D-72076 Tubingen, Germany..
    Wilhelm, Ines
    Univ Childrens Hosp Zurich, Child Dev Ctr, Zurich, Switzerland..
    Benedict, Christian
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Functional Pharmacology.
    Born, Jan
    Univ Tubingen, Inst Med Psychol & Behav Neurobiol, Otfried Muller Str 25, D-72076 Tubingen, Germany.;German Ctr Diabet Res DZD, Tubingen, Germany.;Univ Tubingen IDM, Helmholtz Ctr Munich, Inst Diabet Res & Metab Dis, Tubingen, Germany..
    Hallschmid, Manfred
    Univ Tubingen, Inst Med Psychol & Behav Neurobiol, Otfried Muller Str 25, D-72076 Tubingen, Germany.;German Ctr Diabet Res DZD, Tubingen, Germany.;Univ Tubingen IDM, Helmholtz Ctr Munich, Inst Diabet Res & Metab Dis, Tubingen, Germany..
    Intranasal insulin decreases circulating cortisol concentrations during early sleep in elderly humans2017In: Neurobiology of Aging, ISSN 0197-4580, E-ISSN 1558-1497, Vol. 54, 170-174 p., 170e174Article in journal (Refereed)
    Abstract [en]

    Aging is associated with increases in hypothalamic-pituitary-adrenal (HPA) axis activity that can predispose to metabolic and cognitive impairments. We investigated in elderly and young subjects whether intranasal insulin administration to the human brain reduces early-sleep nadir concentrations of adrenocorticotropin and cortisol, that is, indicators of baseline HPA axis activity. In within-subject comparisons, intranasal insulin (160 IU) or placebo was administered to 14 elderly (mean age 70.0 years) and 30 young (23.6 years) healthy subjects before bedtime. Sleep was polysomno-graphically assessed and blood samples were repeatedly collected. Elderly compared with young participants displayed increased early-sleep cortisol concentrations (p < 0.04) and reductions in slow wave and REM sleep (p < 0.001). Insulin administration reduced cortisol levels between 2300 hours and 0020 hours in the elderly (p = 0.03) but not young participants (p = 0.56; p = 0.003 for interaction). Findings indicate that central nervous insulin acts as an inhibitory signal in basal HPA axis activity regulation and suggest that intranasal insulin may normalize sleep-associated stress axis activity in older age.

  • Malmström, Malin
    et al.
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Innovation and Design.
    Johansson, Jeaneth
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Innovation and Design.
    Wincent, Joakim
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Innovation and Design.
    We Recorded VCs’ Conversations and Analyzed How Differently They Talk About Female Entrepreneurs2017In: Harvard Business Review, ISSN 0017-8012Article, review/survey (Other academic)
  • Public defence: 2017-06-09 10:00 Geijersalen (Eng6-1023), Uppsala
    Rydberg, Andreas
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Arts, Department of History of Science and Ideas.
    Inner Experience: An Analysis of Scientific Experience in Early Modern Germany2017Doctoral thesis, monograph (Other academic)
    Abstract [en]

    In the last decades a number of studies have shed light on early modern scientific experience. While some of these studies have focused on how new facts were forced out of nature in so-called experimental situations, others have charted long-term transformations. In this dissertation I explore a rather different facet of scientific experience by focusing on the case of the Prussian university town Halle in the period from the late seventeenth till the mid-eighteenth century. At this site philosophers, theologians and physicians were preoccupied with categories such as inner senses, inner experience, living experience, psychological experiments and psychometrics. In the study I argue that these hitherto almost completely overlooked categories take us away from observations of external things to the internal organisation of experience and to entirely internal objects of experience. Rather than seeing this internal side of scientific experience as mere theory and epistemology, I argue that it was an integral and central part of what has been referred to as the cultura animi tradition, that is, the philosophical and medical tradition of approaching the soul as something in need of cultivation, education, disciplination and cure.

    The study contains four empirical chapters. In the first chapter I analyse the meaning and function of experience in Christian Wolff’s philosophy understood as spiritual exercise and cultura animi. In the second chapter I examine experience in the theologian Hermann Francke’s cultura animi, focusing particularly on the relation between scientific experience and what scholars have referred to as religious experience. In the third chapter I chart aesthetic experience in Alexander Baumgarten’s aesthetics. In the fourth chapter I examine the role of experience in the medicine of Georg Ernst Stahl, Friedrich Hoffmann and their followers. The analysis of medical experience channels the discussion into questions regarding the relation between the cultura animi tradition and the kind of attitudes, practices and processes that have been connected to modern objectivity.

     

  • Wahab, Tara
    et al.
    Public Health Agency of Sweden; Swedish Forum for Biopreparedness Diagnostics.
    Skarp, Astrid
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Microbiology and Infectious Medicine, Clinical Bacteriology.
    Båverud, Viveca
    SVA.
    Kaden, Rene
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical Microbiology and Infectious Medicine, Clinical Bacteriology.
    GIFeGSH: A New Genomic Island Might Explain the Differences in Brucella Virulence2017In: Open Journal of Animal Sciences, ISSN 2161-7597, E-ISSN 2161-7627, Vol. 7, 141-148 p.Article in journal (Refereed)
    Abstract [en]

    An imported dog was confirmed to be positive with canine brucellosis in Sweden in 2010. The whole genome of Brucella canis SVA10 was subjected to phage analysis (WGS-PA) and was assigned to the Asian B. canis cluster. Further analysis indicated that the genome of B. canis SVA10 is smaller compared to genomes of the same species. A 35,781 bp genomic island (GI) was found to be absent in strain SVA10 which was detected by read mapping the paired reads to the genome of B. canisATCC 23,365T. The lacking genes of genomic island GIFeGSH are mainly coding for iron uptake enzymes and parts of the glutathione pathway. A screening of all available whole genome sequences of Brucella strains confirmed that GIFeGSH is also missing in four more strains of B. canis but present in several strains of B. abortusB. melitensisB. suisB. ovisB. microti, B. pinnipedialis, and B. cetiParts of the GI were present, but scattered in two other B. canis strains. The aim of this study was to find differences in the genomes of Brucella which might explain former described differences in virulence. The analysis was extended to all available Brucella genomes after the detection of a genomic island in strain SVA10.

  • Public defence: 2017-06-07 10:15 Hörsal 2, Uppsala
    Murzabekov, Marat
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Social and Economic Geography.
    Political Pasture: A Governmentality Analysis of Community-Based Pasture Management in Kyrgyzstan2017Doctoral thesis, monograph (Other academic)
    Abstract [en]

    This thesis seeks to understand the development and implementation of the community-based pasture management policy in Kyrgyzstan, which transferred the responsibility for pasture-use planning from state administrative organs to local community-based organizations.

    Using document analysis, this thesis contextualizes the emergence and evolution of the policy’s key premises, including the advantages of community-based management compared to state-centered management. Using interviews and observations, this thesis draws out individual experiences of herders, forestry service officials and the members of pasture committees with the implementation of the policy in the Kadamzhai district of Kyrgyzstan.

    Findings suggest that historical continuities in pasture governance play an important role in the functioning of such policies. On the national level, the reliance of the state on the Soviet administrative and territorial division has reinforced pasture-use fragmentation, where different institutional actors struggle for authority over pastures. These struggles can be observed on the local level, where the implementation of policy is often challenged by forestry officials believing in the advantages of the Soviet fortress conservation, rather than community-based management.

    Second, the local outcomes of policy depend on the compliant or resistant subject positions of individuals involved in pasture use. Policy implementation succeeded in the recruitment of compliant pasture committee chairmen, who claim to be interested in bringing good to the communities through steering the use of pastures. However, the procedures for the establishment of committees contributed to their top-down functioning, where herders often consider the committees as a state agency and find different strategies to avoid their imposed payments.

  • Aghanavesi, Somayeh
    et al.
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Nyholm, Dag
    Marina, Senek
    Bergquist, Filip
    Memedi, Mevludin
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    A smartphone-based system to quantify dexterity in Parkinson's disease patients2017In: Informatics in Medicine Unlocked, ISSN 2352-9148Article in journal (Refereed)
    Abstract [en]

    Objectives: The aim of this paper is to investigate whether a smartphone-based system can be used to quantify dexterity in Parkinson’s disease (PD). More specifically, the aim was to develop data-driven methods to quantify and characterize dexterity in PD. Methods: Nineteen advanced PD patients and 22 healthy controls participated in a clinical trial in Uppsala, Sweden. The subjects were asked to perform tapping and spiral drawing tests using a smartphone. Patients performed the tests before, and at pre-specified time points after they received 150% of their usual levodopa morning dose. Patients were video recorded and their motor symptoms were assessed by three movement disorder specialists using three Unified PD Rating Scale (UPDRS) motor items from part III, the dyskinesia scoring and the treatment response scale (TRS). The raw tapping and spiral data were processed and analyzed with time series analysis techniques to extract 37 spatiotemporal features. For each of the five scales, separate machine learning models were built and tested by using principal components of the features as predictors and mean ratings of the three specialists as target variables. Results: There were weak to moderate correlations between smartphone-based scores and mean ratings of UPDRS item #23 (0.52; finger tapping), UPDRS #25 (0.47; rapid alternating movements of hands), UPDRS #31 (0.57; body bradykinesia and hypokinesia), sum of the three UPDRS items (0.46), dyskinesia (0.64), and TRS (0.59). When assessing the test-retest reliability of the scores it was found that, in general, the clinical scores had better test-retest reliability than the smartphone-based scores. Only the smartphone-based predicted scores on the TRS and dyskinesia scales had good repeatability with intra-class correlation coefficients of 0.51 and 0.84, respectively. Clinician-based scores had higher effect sizes than smartphone-based scores indicating a better responsiveness in detecting changes in relation to treatment interventions. However, the first principal component of the 37 features was able to capture changes throughout the levodopa cycle and had trends similar to the clinical TRS and dyskinesia scales. Smartphone-based scores differed significantly between patients and healthy controls. Conclusions: Quantifying PD motor symptoms via instrumented, dexterity tests employed in a smartphone is feasible and data from such tests can also be used for measuring treatment-related changes in patients.

  • Thunman, Elin
    et al.
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Sociology.
    Persson, Marcus
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Sociology.
    Boundary practices and social media: The case of teachers’ use of Facebook to communicate with pupils2017In: Human IT, ISSN 1402-151X, Vol. 13, no 3, 24-48 p.Article in journal (Refereed)
    Abstract [en]

    The increasing integration of information and communication technologies in work life have fueled the interest in boundary blurring effects on work-home balance. Teachers is an occupational group that has been particularly fast to adopt social media as work tool, however, little is known about how they use of social media in relation to boundary blurring effects. The aim of this study is to inquire into how teachers manage boundaries between home and work domains when using Facebook as work tool to communicate with pupils. Qualitative interviews were done with secondary teachers from three schools about their use of Facebook and their experiences of boundary work. The narratives were inductively categorized according to the main practices deployed by the teachers and interpreted with the help of boundary theory. The findings are presented according to three main practices – virtual, physical, and communicative – that the teachers adopt to integrate and segment home and work domain using Facebook.

  • Public defence: 2017-06-13 13:00 sal FB42, AlbaNova universitetscentrum, Stockholm
    Majidzadeh Garjani, Babak
    Stockholm University, Faculty of Science, Department of Physics. Nordita.
    On Aspects of Anyons and Quantum Graphs2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis consists of two distinct parts. The first part, based on the first two accompanied papers, is in the field of topological phases of matter and the second part, based on the third accompanied paper, looks at a problem in the field of quantum graphs, a rapidly growing field of mathematical physics.

    First, we investigate the entanglement property of the Laughlin state by looking at the rank of the reduced density operator when particles are divided into two groups. We show that the problem of determining this rank translates itself into a  question about symmetric polynomials, namely, one has to determine the lower bound for the degree in each variable of the symmetric polynomials that vanish under a transformation that clusters the particles into groups of equal size and then brings the particles in each group together. Although we were not able to prove this, but we were able to determine the lower bound for the total degree of symmetric polynomials that vanish under the  transformation described. Moreover, we were able to characterize all symmetric polynomials that vanish under this transformation.

    In the second paper, we introduce a one-dimensional model of interacting su(2)k anyons. The specific feature of this model is that, through pairing terms present in the Hamiltonian,  the number of anyons of the chain can fluctuate. We also take into account the possibility that anyons hop to empty neighboring sites. We investigate the model in five different points of the parameter space. At one of these points, the Hamiltonian of the model becomes a sum of projectors and we determine the explicit form of all the zero-energy ground states for odd values of k. At the other four points, the system is integrable and we determine the behavior of the model at these integrable points. In particular, we show that the system is critical and determine the CFT describing the system at these points.

    It is known that there are non-Hermitian Hamiltonians whose spectra are entirely real. This property can be understood in terms of a certain symmetry of these Hamiltonians, known as PT-symmetry. It is also known that the spectrum of a non-Hermitian PT-symmetric Hamiltonian has reflection symmetry with respect to the real axis. We then ask the reverse question whether or not the reflection symmetry of a non-Hermitian Hamiltonian necessarily implies that the Hamiltonian is PT-symmetric. In the context of quantum graphs, we introduce a model for which the answer to this question is positive.

  • Public defence: 2017-06-13 10:00 hörsal 12, hus F, Stockholm
    Belmar Shagulian, Jasmin
    Stockholm University, Faculty of Humanities, Department of Romance Studies and Classics.
    El mito de la Quintrala: Estructuras simbólicas en dos novelas de Gustavo Frías2017Doctoral thesis, monograph (Other academic)
    Abstract [en]

    The purpose of this comparative study is to analyse La Quintrala’s myth as a symbolic discourse, thereby filling a gap in the previous studies about La Quintrala.

    The theoretical and methodological framework of this analysis consists of a hermeneutical approach based on the method of figurative structuralism: mythocriticism. This is a dual classification method of symbols: Diurnal and Nocturnal Orders that expose the symbolic structures formed by symbols and archetypes found in mythemes in a compilation of corpora. The first one is Gustavo Frías’ novels Tres Nombres para Catalina: Catrala (2008) and Tres nombres para Catalina: la doña de Campofrío (2008); the second is a historic essay (hypotext), Benjamín Vicuña Mackenna’s Los Lisperguer y la Quintrala (1944), and four novels: Magdalena Petit’s (2009) La Quintrala, Mercedes Valdivieso’s (1991) Maldita yo entre las Mujeres, Virginia Vidal’s (2002) Oro, veneno y puñal, and Gustavo Frías’ El Inquisidor (2008).

    Mythocriticism is employed in the analysis to show what the mythical structure of the hero’s journey (Separation, Initiation, Return) reveal. Such journey is combined structurally with the Mother archetype (White, Red and Black Goddess), the intrinsic archetype of La Quintrala’s myth. The heroic structure unveils its own mythemes, La Quintrala’s and the first corpus’s mytheme through the diachronic and synchronic flow of the hero’s journey. This method permits to identify and compare the progression of the symbolic structures.

    The analysis demonstrates a transformation of the symbolic structures between both corpora. This survey reveals that Vicuña Mackenna and Petit, and partially Vidal and El Inquisidor, exhibit an inclination to the diurnal symbols that strengthen, through a heterodiegetic narrator, the representations of the witch-femme fatale, counteractive attributes of the Red and Black Goddesses in the myth. Valdivieso, on the other hand, shows a propensity to the nocturnal symbols of inversion and intimacy that emphasize the Red Goddess’ features, though the novel also exposes La Quintrala as a witch-femme fatale. This exposure occurs through the use of both an autodiegetic narrator –La Quintrala– and a heterodiegetic one –the hypotext embodied in the popular voice– that appear to contrast each other. Finally, in Tres Nombres para Catalina, La Quintrala as the autodiegetic narrator dominates the whole story. She personifies the Great Goddess archetype who bestows her new positive attributes during the adventure. This novel assumes primordially the nocturnal symbolism incarnated by both the mystical and the synthetical structures and relegates the diurnal discourse of the hypotext to a secondary position in the narrative. Nonetheless, Tres Nombres para Catalina’s narrative still relies on the hypotext to reproduce and reconstruct all the mythemes in the myth of La Quintrala.

    Conclusively, the results of this analysis indicate that the identification of all the mythemes supports the hypothesis of a transformation in the symbolic structures which characterize La Quintrala in both corpora. This reveals the embodiment of Tres Nombres para Catalina’s own mytheme, consisting of a vindication and a recognition to her indigenous heritage, and the acceptance of her mestizaje. As a consequence, Tres nombres para Catalina, in comparison to the second corpus, diverges and expands the symbolic structures, but still shows a continuity of the myth.

  • Public defence: 2017-06-13 13:00 Magnélisalen, Kemiska övningslaboratoriet, Stockholm
    Li, Yunxiang
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK).
    Modification of zeolites and synthesis of SAPO-templated carbon2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Zeolites are crystalline aluminosilicates with diverse structures and uniform porosities. They are widely used as catalysts, adsorbents and ion-exchangers in industry. Direct or post modifications optimize the performance of zeolites for different applications. In this thesis, IZM-2 and TON-type zeolites were synthesized, modified and studied. In addition, FAU-type zeolite and silicoaluminophosphate (SAPO) molecular sieves were applied as templates for the preparation of microporous carbons.

    In the first part of this thesis, the IZM-2 zeolite with an unknown structure was synthesized. We focused on the increasing the secondary porosity and the varied framework compositions upon post modifications.

    The structure determination of this IZM-2 zeolite was hindered by the small size of crystals. In the second part of this thesis, the synthesis composition was directly modified in order to increase the crystal sizes. IZM-2 crystals were enlarged by excluding the aluminium atoms from the framework. The micropores of the obtained pure-silica polymorphs were activated by ion-exchanging alkali-metal ions with protons.

    Typically, TON-type zeolites that are synthesized at hydrothermal conditions under stirring have needle-shaped crystals. In the third part of this thesis, snowflake-shaped aggregates were produced by using static hydrothermal conditions for the synthesis of TON-type zeolites. The effects of synthesis parameters on the growth and morphology of crystals were discussed in detail.

    In the last part of this thesis, microporous carbons with a structural regularity were prepared by chemical vapour deposition (CVD) of propylene using a silicoaluminophosphate (SAPO-37) template. Compared to the conventional zeolite templates, the SAPO template could be removed under mild conditions, without using hydrofluoric acid, and the generated carbons had a large specific surface area and a high fraction of ultrasmall micropores.

  • Public defence: 2017-06-13 13:00 Lilla hörsalen, NOD-huset, Kista
    Xiao, Bin
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences.
    Data-Centric Network of Things: A Method for Exploiting the Massive Amount of Heterogeneous Data of Internet of Things in Support of Services2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Internet of things (IoT) generates massive amount of heterogeneous data, which should be efficiently utilized to support services in different domains. Specifically, data need to be supplied to services by understanding the needs of services and by understanding the environment changes, so that necessary data can be provided efficiently but without overfeeding. However, it is still very difficult for IoT to fulfill such data supply with only the existing supports of communication, network, and infrastructure; while the most essential issues are still unaddressed, namely the heterogeneity issue, the recourse coordination issue, and the environments’ dynamicity issue. Thus, this necessitates to specifically study on those issues and to propose a method to utilize the massive amount of heterogeneous data to support services in different domains.

    This dissertation presents a novel method, called the data-centric network of things (DNT), which handles heterogeneity, coordinates resources, and understands the changing IoT entity relations in dynamic environments to supply data in support of services. As results, various services based on IoT (e.g., smart cities, smart transport, smart healthcare, smart homes, etc.) are supported by receiving enough necessary data without overfeeding.

    The contributions of the DNT to IoT and big data research are: firstly the DNT enables IoT to perceive data, resources, and the relations among IoT entities in dynamic environments. This perceptibility enhances IoT to handle the heterogeneity in different levels. Secondly, the DNT coordinates IoT edge resources to process and disseminate data based on the perceived results. This releases the big data pressure caused by centralized analytics to certain degrees. Thirdly, the DNT manages entity relations for data supply by handling the environment dynamicity. Finally, the DNT supply necessary data to satisfy different service needs, by avoiding either data-hungry or data-overfed status.