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  • Antell, Elina
    et al.
    Royal Institute of Art.
    Hofstedt, Ulf
    Royal Institute of Art.
    Klingberg, Erland
    Royal Institute of Art.
    Rauma, Tuula
    Royal Institute of Art.
    Wennerberg, Charlotta
    Royal Institute of Art.
    Antell, Olof (Editor)
    Royal Institute of Art.
    von Knorring, Peter (Editor)
    Royal Institute of Art.
    Rydberg, Per (Editor)
    Royal Institute of Art.
    Svartsjö slott: dokumentation, analys och restaureringsförslag1989Report (Other (popular science, discussion, etc.))
    Abstract [sv]

    Läsåret 1988-89 ägnade Arkitekturskolans avdelning för restaureringskonst åt två större restaureringsprojekt - Svartsjö och Bogesund. Båda slotten står outnyttjade och erbjuder goda exempel på de tekniska och kulturhistoriska komplikationerna inom den kvalificerade byggnadsvården. 

    I den föreliggande skriften finns både utställningen som visades vid Konstakademien våren 1989 och ett bearbetat förslag till ett resataureringsprogram för Svartsjö slott redovisade.

  • Jensen, Carl
    et al.
    Executive, Forskningsinstitut, IVL Swedish Environmental Research Institute.
    Stenmarck, Åsa
    Executive, Forskningsinstitut, IVL Swedish Environmental Research Institute.
    Sörme, Louise
    SCB.
    Dunsö, Olof
    SCB.
    Matavfall 2010 från jord till bord2011Report (Other academic)
  • Jensen, Carl
    et al.
    Executive, Forskningsinstitut, IVL Swedish Environmental Research Institute.
    Stare, Malin
    Executive, Forskningsinstitut, IVL Swedish Environmental Research Institute.
    Stenmarck, Åsa
    Executive, Forskningsinstitut, IVL Swedish Environmental Research Institute.
    Dunsö, Olof
    SCB.
    Sörme, Louise
    SCB.
    Beräkningsmetod för uppföljning av etappmå-let om resurshushållning i livsmedelskedjan, bio-logisk återvinning2014Report (Other academic)
  • Public defence: 2017-12-18 13:00 J1640, Karlskrona
    García-Martín, Eva
    Blekinge Institute of Technology, Faculty of Computing, Department of Computer Science and Engineering.
    Extraction and Energy Efficient Processing of Streaming Data2017Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    The interest in machine learning algorithms is increasing, in parallel with the advancements in hardware and software required to mine large-scale datasets. Machine learning algorithms account for a significant amount of energy consumed in data centers, which impacts the global energy consumption. However, machine learning algorithms are optimized towards predictive performance and scalability. Algorithms with low energy consumption are necessary for embedded systems and other resource constrained devices; and desirable for platforms that require many computations, such as data centers. Data stream mining investigates how to process potentially infinite streams of data without the need to store all the data. This ability is particularly useful for companies that are generating data at a high rate, such as social networks.

    This thesis investigates algorithms in the data stream mining domain from an energy efficiency perspective. The thesis comprises of two parts. The first part explores how to extract and analyze data from Twitter, with a pilot study that investigates a correlation between hashtags and followers. The second and main part investigates how energy is consumed and optimized in an online learning algorithm, suitable for data stream mining tasks.

    The second part of the thesis focuses on analyzing, understanding, and reformulating the Very Fast Decision Tree (VFDT) algorithm, the original Hoeffding tree algorithm, into an energy efficient version. It presents three key contributions. First, it shows how energy varies in the VFDT from a high-level view by tuning different parameters. Second, it presents a methodology to identify energy bottlenecks in machine learning algorithms, by portraying the functions of the VFDT that consume the largest amount of energy. Third, it introduces dynamic parameter adaptation for Hoeffding trees, a method to dynamically adapt the parameters of Hoeffding trees to reduce their energy consumption. The results show an average energy reduction of 23% on the VFDT algorithm.

  • Woolfson, Charles
    Linköping University, Department of Social and Welfare Studies, REMESO - Institute for Research on Migration, Ethnicity and Society. Linköping University, Faculty of Arts and Sciences.
    The Politics of Brexit: European Free Movement of Labourand Labour Standards2017Report (Other academic)
    Abstract [en]

    This paper attempts to reassess the Brexit debate in the UK over immigration and free movement of labour in terms of the politics of austerity. It advances a progressive case for Brexit based on regaining national sovereignty to enable the effective defence of national labour standards outside of the neoliberal European project. The issue of labour standards is a cause that paradoxically the current Conservative administration has sought to champion, although on a highly contestable basis. In the UK general election of 2017, the Labour Party has significantly advanced its position on the basis of an anti-austerity program while the Conservative government has entered into a likely terminal crisis. It is argued that rejecting membership of the supranational European Union has the potential to advance labour rights further in an inclusive and non-xenophobic way.

  • Borghei, Behbood
    Linköping University, Department of Management and Engineering, Project Innovations and Entrepreneurship. Linköping University, Faculty of Science & Engineering.
    Empirical Report: Pioneers in electric city buses: Stockholm, Gothenburg, Umeå, Helsinki, Copenhagen, Hamburg2016Report (Other academic)
    Abstract [en]

    Stockholm is one of the core demonstration cities in the EU-funded project for zero emission urban bus systems (ZeEUS). The city has ambitious environmental plans for sustainable public transportation for the coming decades. Stockholm’s environmental objectives for 2030 are:

    • All fleets to be running on 100 % renewable fuel (already achieving in 2020)
    • Reducing 75 % of particles and NOx based on 2009
    • Reducing 35% of the energy usage per passenger/km in public transport  based on 2007

    As it is apparent, Stockholm city council does not call for any particular technology in achieving the abovementioned environmental goals. Today, a large proportion of the bus fleet in Stockholm are running on either biogas or bio-diesel (Olsson, 2015; Olsson et al., 2015). However, achieving the other two set of goals i.e. reducing NOx/PMs and decreasing energy intensity rather require hybridization or electrification of the bus fleet on top of the renewable fuel changeover strategy over the long run. Thus, participation in the ZeEUS project is seen as the first step towards implementation of hybrid/electric vehicles in the city bus operations in real life conditions. According to ZeEUS website: “The demo wishes to prove that this system can be an important factor in the future public transport systems in the EU without big changes in the infrastructure. In the long term, the ZeEUS project will give important contribution to the cities strategic plans regarding electric buses and demo aims to continue operating after the project lifetime for a demo operational span of 8-12 years.” (ZeEUS, 2016)....

  • Ivarsson, Anna-Karin
    et al.
    SCB.
    Skårman, Tina
    Executive, Forskningsinstitut, IVL Swedish Environmental Research Institute.
    Energy Statistics versus Environmental Reports2003Report (Other academic)
  • Public defence: 2017-12-15 09:15 Polhemssalen, Uppsala
    Jönsson, Olof
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and Condensed Matter Physics. Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Cell and Molecular Biology, Molecular biophysics.
    Ultrafast Structural and Electron Dynamics in Soft Matter Exposed to Intense X-ray Pulses2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Investigations of soft matter using ultrashort high intensity pulses have been made possible through the advent of X-ray free-electrons lasers. The last decade has seen the development of a new type of protein crystallography where femtosecond dynamics can be studied, and single particle imaging with atomic resolution is on the horizon. The pulses are so intense that any sample quickly turns into a plasma. This thesis studies the ultrafast transition from soft matter to warm dense matter, and the implications for structural determination of proteins.                   

    We use non-thermal plasma simulations to predict ultrafast structural and electron dynamics. Changes in atomic form factors due to the electronic state, and displacement as a function of temperature, are used to predict Bragg signal intensity in protein nanocrystals. The damage processes started by the pulse will gate the diffracted signal within the pulse duration, suggesting that long pulses are useful to study protein structure. This illustrates diffraction-before-destruction in crystallography.

    The effect from a varying temporal photon distribution within a pulse is also investigated. A well-defined initial front determines the quality of the diffracted signal. At lower intensities, the temporal shape of the X-ray pulse will affect the overall signal strength; at high intensities the signal level will be strongly dependent on the resolution.

    Water is routinely used to deliver biological samples into the X-ray beam. Structural dynamics in water exposed to intense X-rays were investigated with simulations and experiments. Using pulses of different duration, we found that non-thermal heating will affect the water structure on a time scale longer than 25 fs but shorter than 75 fs. Modeling suggests that a loss of long-range coordination of the solvation shells accounts for the observed decrease in scattering signal.

    The feasibility of using X-ray emission from plasma as an indicator for hits in serial diffraction experiments is studied. Specific line emission from sulfur at high X-ray energies is suitable for distinguishing spectral features from proteins, compared to emission from delivery liquids. We find that plasma emission continues long after the femtosecond pulse has ended, suggesting that spectrum-during-destruction could reveal information complementary to diffraction.

  • Lin, Yingbo
    et al.
    Karolinska Inst, Dept Pathol & Oncol, CCK R8 04, Stockholm, Sweden..
    Liu, Hongyu
    Karolinska Inst, Dept Pathol & Oncol, CCK R8 04, Stockholm, Sweden.;Guangdong Ocean Univ, Fisheries Coll, Lab Aquat Anim Nutr Feed, Zhanjiang, Peoples R China..
    Waraky, Ahmed
    Karolinska Inst, Dept Pathol & Oncol, CCK R8 04, Stockholm, Sweden..
    Haglund, Felix
    Karolinska Inst, Dept Pathol & Oncol, CCK R8 04, Stockholm, Sweden..
    Agarwal, Prasoon
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Experimental and Clinical Oncology. Karolinska Univ Hosp, Div Clin Immunol, Dept Lab Med LABMED H5, Stockholm, Sweden.
    Jernberg Wiklund, Helena
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Experimental and Clinical Oncology.
    Warsito, Dudi
    Karolinska Inst, Dept Pathol & Oncol, CCK R8 04, Stockholm, Sweden..
    Larsson, Olle
    Karolinska Inst, Dept Pathol & Oncol, CCK R8 04, Stockholm, Sweden..
    SUMO-modified insulin-like growth factor 1 receptor (IGF-1R) increases cell cycle progression and cell proliferation2017In: Journal of Cellular Physiology, ISSN 0021-9541, E-ISSN 1097-4652, Vol. 232, no 10, 2722-2730 p.Article in journal (Refereed)
    Abstract [en]

    Increasing number of studies have shown nuclear localization of the insulin-like growth factor 1 receptor (nIGF-1R) in tumor cells and its links to adverse clinical outcome in various cancers. Any obvious cell physiological roles of nIGF-1R have, however, still not been disclosed. Previously, we reported that IGF-1R translocates to cell nucleus and modulates gene expression by binding to enhancers, provided that the receptor is SUMOylated. In this study, we constructed stable transfectants of wild type IGF1R (WT) and triple-SUMO-site-mutated IGF1R (TSM) using igf1r knockout mouse fibroblasts (R-). Cell clones (R-WT and R-TSM) expressing equal amounts of IGF1R were selected for experiments. Phosphorylation of IGF-1R, Akt, and Erk upon IGF-1 stimulation was equal in R-WT and R-TSM. WT was confirmed to enter nuclei. TSM did also undergo nuclear translocation, although to a lesser extent. This may be explained by that TSM heterodimerizes with insulin receptor, which is known to translocate to cell nuclei. R-WT proliferated substantially faster than R-TSM, which did not differ significantly from the empty vector control. Upon IGF-1 stimulationG1-S-phase progression of R-WT increased from 12 to 38%, compared to 13 to 20% of R-TSM. The G1-S progression of R-WT correlated with increased expression of cyclin D1, A, and CDK2, as well as downregulation of p27. This suggests that SUMO-IGF-1R affects upstream mechanisms that control and coordinate expression of cell cycle regulators. Further studies to identify such SUMO-IGF-1R dependent mechanisms seem important.

  • Dubiec, Anna
    et al.
    Polish Acad Sci, Museum & Inst Zool, Warsaw, Poland..
    Podmokla, Edyta
    Jagiellonian Univ, Inst Environm Sci, Krakow, Poland..
    Gustafsson, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Intra-individual changes in haemosporidian infections over the nesting period in great tit females2017In: Parasitology Research, ISSN 0932-0113, E-ISSN 1432-1955, Vol. 116, no 9, 2385-2392 p.Article in journal (Refereed)
    Abstract [en]

    Prevalence of haemosporidian parasites in bird populations varies temporally both between years and within a year. In contrast to variation at the population level, relatively little is known about variation in infection attributes at the individual level, especially in non-migratory species. We examined intra-individual changes in the presence and identity of haemosporidian parasites (genera Plasmodium and Haemoproteus) over the course of the nesting period in females of great tits (Parus major)-a species considered to be resident over much of its distribution range. Birds were sampled during two stages of the nesting period: nest building and nestling rearing. The mean time interval between sampling occasions was 43 days. Between the first and second samplings, 30.6% of females gained at least one parasite lineage and 18.5% lost the lineage. Haemoproteus gains were over three times more common than Plasmodium gains. The probability of the lineage gain decreased with the date of the first sampling, was higher in individuals in better body condition and differed between years, but was not associated with the host age. The probability of the lineage loss was not explained by any of the considered parameters except for year. These results indicate that in a large proportion of a population, infection attributes (presence/absence and/or parasite identity) may change over the nesting period and the occurrence of such changes may be associated with the individual quality. Consequently, this phenomenon should be taken into account to correctly interpret parasite-mediated effects.

  • Ivarsson, Anna-Karin
    SCB.
    Improved statistics for SSAB, refineries and lime producers2003Report (Other academic)
  • Public defence: 2017-12-15 10:00 Lindhalsalen, Uppsala
    Martinossi-Allibert, Ivain
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Sexual Selection and Adaptation to Novel Environments2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The work included in this thesis aims at exploring the environmental sensitivity of benefits and costs of sexual selection through a combined empirical and theoretical effort, to increase our understanding of the impact of environmental change on sexually reproducing populations.Can sexual selection promote adaptation to novel environments? Sexual selection for good genes should accelerate adaptation by granting higher reproductive success to individuals of high genetic quality. However, sexual conflict is a frequent outcome of sexual reproduction and may often be detrimental to population fitness. Experimental evolution has shown that the role of sexual selection in adaptation is variable, because of a complex balance between the detrimental and beneficial effects described above.The present thesis is investigating the role of sexual selection in adaptation by focusing on the sex-specific strength of selection and the intensity of intralocus sexual conflict (IaSC) in ancestral and novel environments. The sex-specific strength of selection is a valuable proxy for the benefits of sexual reproduction, since a male-bias in selection caused by sexual selection should allow efficient purging of deleterious alleles with little impact on female fecundity and cost to population fitness.This thesis investigates both sex-specific selection and IaSC across benign and novel environments in two species of seed beetles, Callosobruchus maculatus and Acanthoscelides obtectus, and includes a theoretical model of the effect of environmental change on of sexual selection. The empirical part of my results indicates that, generally, selection at the adult stage is male biased but that this male bias may be reduced under stress, pointing towards reduced benefits of sexual selection under rapid environmental change. Additional simulations suggest that the frequency dependent nature of sexual selection alone could explain this trend. No empirical support was found for the reduction of IaSC under stress.It is becoming crucial today to understand the impact of environmental change on natural populations. This thesis brings new material adding to our understanding of the role of sexual selection within that particular issue. The outcome of sexual selection is dependent on a variety of mechanisms, such as good genes processes and sexual conflict, which are very likely to be dependent on ecological factors and specificity of the system studied. For that reason, carefully controlled experiments on laboratory systems and mathematical modelling are necessary steps that should ultimately lead to the study of similar questions in natural systems.

  • Public defence: 2017-12-15 09:15 ACAS, A-huset, Linköping
    Päivärinne, Sofia
    Linköping University, Department of Management and Engineering, Environmental Technology and Management. Linköping University, Faculty of Science & Engineering.
    Utilisation of Excess Heat Towards a Circular Economy: Implications of interorganisational collaborations and strategic planning2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In order to significantly lower the environmental impact from human activities, numerous efforts and approaches related to the transformation of human activities have developed during the last decades. Examples of such efforts are policies and strategies at different levels, some with a top-down approach focusing on extensive institutional changes, and some with a bottom-up approach focusing on industrial actors and industry-led activities.

    One essential aspect of these efforts concerns the energy used producing the products and services provided within our society. This includes, for example, improved efficiency of processes in order to minimise the amount of energy used, or optimisation of efficiency by using energy with the lowest possible exergy value. It can also be about re-use of energy, which is the focus of this thesis. Heat, which is the main by-product of all energy systems, can be utilised for heating purposes to lower the primary energy demand for heating. Increased utilisation of excess heat, however, requires collaboration between normally unrelated actors, those with a supply of and those demanding excess heat.

    In Sweden, which is a Northern European country with high demand for heat, the tradition of large energy-intensive manufacturing industries generating large amounts of excess heat, in combination with well-established district heating distribution systems, constitute good conditions for excess heat utilisation. Despite the fact that Sweden is among the world leaders in utilising excess heat, there is however, still a large unutilised potential.

    From this background, the objective of this thesis is to identify challenges behind excess heat utilisation for heating purposes, and to propose practical suggestions to facilitate expanded excess heat utilisation. The overall objective is analysed with a focus on drivers and barriers behind interorganisational collaborations on excess heat utilisation, important components of interorganisational business models and how the technical conditions regarding supply and demand could be facilitated by strategic municipal spatial planning processes. The research is largely based on interviews conducted with societal actors with different perspectives on excess heat utilisation; energy companies, industries generating high-grade excess heat, facilities generating low-grade excess heat, facilities demanding low-grade excess heat, experts of utilisation of low-grade excess heat, branch organisations, municipal spatial planners, energy- and climate advisors, and developers. Document studies have been conducted in order to collect case specific knowledge. The research questions are explored based on literature studies on the principles of industrial symbiosis, business model perspective and strategic planning. Further, they are examined in a Swedish context.

    It is concluded that the three perspectives complement each other by providing a system perspective on increased utilisation of excess heat as they seek to contribute both environmental and financial benefits at both a company and societal level. In order to facilitate further utilisation of excess heat it is important to focus on the organisational factors of humility, honesty, transparency, trust, fine-grained information transfer, joint problem solving, and shared visions of common goals, which are important conditions behind development of functional and long-term durable collaborations. Business models for collaboration could contribute to the creation of these organisationally important conditions. Such business models could also provide knowledge on how to create and capture joint values. For some collaborations involving actors lacking the technical knowledge related to the capturing and distribution of excess heat, a third-party providing services related to the technical knowledge required could be beneficial. Collaborations in which one of the actors consists of an energy company often entail the technical knowledge required. This implies that different collaborations involving different types of actors and under different prevailing financial, technical and organisational conditions require customised and flexible business solutions. Local authorities could, through their overall function, initiate interorganisational collaborations on excess heat within the framework of municipal spatial planning. The results do however show that the investigated planning processes could develop more extensive stakeholder participation to include further societal actors related to excess heat. More extensive stakeholder participation, have the potential to initiate new development of collaborations on excess heat between normally unrelated actors, both with and without involvements of third-party knowledge brokers. A broader participation is also expected to result in increased knowledge on how to plan to further facilitate the condition of excess heat utilisation.

  • Public defence: 2017-12-15 09:00 M2, Stockholm
    Zhou, Xiamo
    KTH, School of Electrical Engineering (EES), Micro and Nanosystems.
    OSTE Microfluidic Technologies for Cell Encapsulation and Biomolecular Analysis2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In novel drug delivery system, the encapsulation of therapeutic cells in microparticles has great promises for the treatment of a range of health con- ditions. Therefore, the encapsulation material and technology are of great importance to the validity and efficiency of the advanced medical therapy. Several unsolved challenges in regards to versatile microparticle synthesis ma- terials and methods form the main obstacle for a translation of novel cell therapy concepts from research to clinical practice.

    Thiol-ene based polymer systems have emerged and gained great popular- ity in material development in general and in biomedical applications specif- ically. The thiol-ene platform is broad and therefore of interest for a variety of applications. At the same time, many aspects of this material platform are largely unexplored, for example material and manufacturing technology developments for microfluidic applications .

    In this Ph.D. thesis, thiol-ene materials are explored for use in cell encap- sulation. The marriage of these two technology fields breeds the possibility for a novel microfluidic cell encapsulation approach using a novel encapsulation material. To this end, several new manufacturing technologies for thiol-ene and thiol-ene-epoxy droplet microfluidic devices were developed. Moreover, core-shell microparticle synthesis for cell encapsulation based on a novel co- synthesis concept using a thiol-ene based material was developed and inves- tigated. Finally, a thiol-ene-epoxy system was also used for the formation of microwells and microchannels that improve protein analysis on microarrays.

    The first part of the thesis presents the background and state-of-the-art technologies in regards to cell therapy, microfluidics, and thiol-ene based ma- terials. In the second part of the thesis, a novel manufacturing approach of thiol-ene-epoxy material as well as core-shell particle co-synthesis in micro- fluidics using thiol-ene based material are presented and characterized. The third part of the thesis presents the cell viability studies of encapsulated cells using the novel encapsulation material and method. In the final part of the thesis, two applications of thiol-ene-epoxy gaskets for protein detection mi- croarrays are presented. 

  • Kabanshi, Alan
    et al.
    HiG.
    Sattari, Amir
    Dalarna University, School of Technology and Business Studies, Construction.
    Linden, Elisabet
    HiG.
    Wigö, Hans
    HiG.
    Sandberg, Mats
    HiG.
    Experimental study on contaminant entrainment in air distribution systemswith free jets2017Conference paper (Refereed)
  • Thunborg, Camilla
    Linköping University, Department of Education and Psychology. Linköping University, Faculty of Educational Sciences.
    Lärande av yrkesidentiteter: en studie av läkare, sjuksköterskor och undersköterskor1999Doctoral thesis, monograph (Other academic)
    Abstract [en]

    This dissertation is concerned with the learning of occupational identities in health care and medical services. The aim is to increase the knowledge of what characterizes occupational identities how these are learnt, and what potential driving forces exist that can contribute to the development of both occupational identities and health care activities.

    Learning is seen as a continuous process of participation in everyday social practices, in which occupational identities are formed, maintained and developed. Both occupational identities and social practices are context-bound. In order to shed light on the forming, maintaining and developing character of learning I have started from three different models; a social-interactionist, an institutional and a contextual.

    The dissertation is based on case studies of three care units. A health-care centre, a medical clinic and an anaesthesia clinic. The study comprises two data-collection phases. The first phase includes interviews with personnel and management at the three care units. The second phase includes self-observation studies in the form of diaries kept by personnel at the medical and anaesthesia clinic.

    It appears from the results that there are both similarities and differences between occupational groups and the activities in which they work. There also exist certain differences that have to do with the individuals' experience, career paths and length of employment. On this basis, occoupational identities can he analyzed on a occupational-related, an activity-related and an individual-related level. Learning can also from this point of view be seen as an interplay between those three levels.

  • Xing, Shan
    et al.
    Chinese Acad Sci, State Key Lab Loess & Quaternary Geol, Shaanxi Key Lab Accelerator Mass Spectrometry Tec, Xian AMS Ctr,Inst Earth Environm, Xian 710061, Shaanxi, Peoples R China..
    Hou, Xiaolin
    Chinese Acad Sci, State Key Lab Loess & Quaternary Geol, Shaanxi Key Lab Accelerator Mass Spectrometry Tec, Xian AMS Ctr,Inst Earth Environm, Xian 710061, Shaanxi, Peoples R China.;Techn Univ Denmark, Ctr Nucl Technol, DK-4000 Roskilde, Denmark..
    Aldahan, Ala
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. United Arab Emirates Univ, Dept Geol, Al Ain 17511, U Arab Emirates..
    Possnert, Göran
    Uppsala University, Disciplinary Domain of Science and Technology, För teknisk-naturvetenskapliga fakulteten gemensamma enheter, Tandem Laboratory.
    Shi, Keliang
    Techn Univ Denmark, Ctr Nucl Technol, DK-4000 Roskilde, Denmark.;Lanzhou Univ, Sch Nucl Sci & Technol, Lanzhou 73000, Gansu, Peoples R China..
    Yi, Peng
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. Hohai Univ, Coll Hydrol & Water Resources, Nanjing 210098, Jiangsu, Peoples R China..
    Zhou, Weijian
    Chinese Acad Sci, State Key Lab Loess & Quaternary Geol, Shaanxi Key Lab Accelerator Mass Spectrometry Tec, Xian AMS Ctr,Inst Earth Environm, Xian 710061, Shaanxi, Peoples R China..
    Water Circulation and Marine Environment in the Antarctic Traced by Speciation of I-129 and I-1272017In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 7, 7726Article in journal (Refereed)
    Abstract [en]

    Emissions of anthropogenic I-129 from human nuclear activities are now detected in the surface water of the Antarctic seas. Surface seawater samples from the Drake Passage, Bellingshausen, Amundsen, and Ross Seas were analyzed for total I-129 and I-127, as well as for iodide and iodate of these two isotopes. The variability of I-127 and I-129 concentrations and their species (I-127(-)/(IO3-)-I-127, I-129(-)/(IO3-)-I-129) suggest limited environmental impact where ((1.15-3.15) x 10(6) atoms/L for I-129 concentration and (0.61-1.98) x 10(-11) for I-129/I-127 atomic ratios are the lowest ones compared to the other oceans. The iodine distribution patterns provide useful information on surface water transport and mixing that are vital for better understanding of the Southern Oceans effects on the global climate change. The results indicate multiple spatial interactions between the Antarctic Circumpolar Current (ACC) and Antarctic Peninsula Coastal Current (APCC). These interactions happen in restricted circulation pathways that may partly relate to glacial melting and icebergs transport. Biological activity during the warm season should be one of the key factors controlling the reduction of iodate in the coastal water in the Antarctic.

  • Asan, Noor Badariah
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Noreland, Daniel
    Umea Univ, Dept Comp Sci, SE-90187 Umea, Sweden..
    Hassan, Emadeldeen
    Umea Univ, Dept Comp Sci, SE-90187 Umea, Sweden.;Menoufia Univ, Dept Elect & Elect Commun, Menoufia 32952, Egypt..
    Redzwan, Syaiful
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Rydberg, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Blokhuis, Taco J.
    Maastricht Univ, Dept Surg, Med Ctr, P Debyelaan 25, NL-6229 HX Maastricht, Netherlands..
    Carlsson, Per-Ola
    Univ Hosp, Dept Med Sci Transplantat & Regenerat Med, SE-75185 Uppsala, Sweden..
    Voigt, Thiemo
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Computer Systems.
    Augustine, Robin
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Intra-body microwave communication through adipose tissue2017In: HEALTHCARE TECHNOLOGY LETTERS, ISSN 2053-3713, Vol. 4, no 4, 115-121 p.Article in journal (Refereed)
    Abstract [en]

    The human body can act as a medium for the transmission of electromagnetic waves in the wireless body sensor networks context. However, there are transmission losses in biological tissues due to the presence of water and salts. This Letter focuses on lateral intra-body microwave communication through different biological tissue layers and demonstrates the effect of the tissue thicknesses by comparing signal coupling in the channel. For this work, the authors utilise the R-band frequencies since it overlaps the industrial, scientific and medical radio (ISM) band. The channel model in human tissues is proposed based on electromagnetic simulations, validated using equivalent phantom and ex-vivo measurements. The phantom and ex-vivo measurements are compared with simulation modelling. The results show that electromagnetic communication is feasible in the adipose tissue layer with a low attenuation of approximate to 2 dB per 20 mm for phantom measurements and 4 dB per 20 mm for ex-vivo measurements at 2 GHz. Since the dielectric losses of human adipose tissues are almost half of ex-vivo tissue, an attenuation of around 3 dB per 20 mm is expected. The results show that human adipose tissue can be used as an intra-body communication channel.

  • Public defence: 2017-12-13 13:00 Auditorium Minus, Uppsala
    Jha, Paridhi
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health.
    ‘Two Sides of a Coin’: Quality of Childbirth Services in Indian Public Health Facilities, from the Perspectives of Women and their Care Providers2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Background: Skilled birth attendance, usually available by promoting childbirth at health care institutions in low-resource settings, is known to prevent maternal and neonatal morbidity and mortality. While institutional childbirths in India have increased at an exponential rate, the infrastructure, material and manpower resources to support this practice are lagging, raising concerns about the quality of childbirth services.

    Methodology: A mixed-method approach was used in this project: in-depth interviews with women (n= 13); and focus-group-discussions with the care providers (n=27) were conducted and analysed using Grounded Theory. A cross-sectional survey (n= 1004) assessed prevalence of Fear of Birth (FoB) and postnatal depressive symptoms (PND), along with satisfaction with childbirth services among women in the immediate postpartum period.

    Results: The system of cashless childbirth provided at the public health facilities, in the women’s experiences, came at the hidden cost of them having to make themselves subordinate to the offered services. The prevalence of FoB and PND was 13.1% and 17.1%, respectively, and these were significantly associated (p < 0.001). Among women with vaginal births (VB), 41.2% had experienced a perineal wound and 59% of them underwent repair without local anaesthesia. While the majority of the women were satisfied (VB 68.7%; Caesarean births 79.2%) with the services; women having VBs at Community Health Centres (nearly 81%) were more commonly satisfied compared to those at the District Hospitals (nearly 60%) (p < 0.001). From the care providers’ perspective, maintaining quality of childbirth services was like a balancing act between the realities of low-resource settings with stakeholders’ expectations. While the providers remained proud and committed; the challenges often left them fatigued, disillusioned, irritable and sceptical.

    Conclusion: There is a need to improve the sensitivity with which childbirth services are being delivered to women coming to public health facilities; as well as towards improving the care providers’ work conditions. Suboptimal birth experiences are associated with the women’s perinatal mental health and satisfaction, while perpetual work challenges may make the care providers frustrated and/or apathetic. Improving manpower resources could reduce work-stress in care providers and thereby improve childbirth processes.

  • Kapur, Jyoti
    University of Borås, Faculty of Textiles, Engineering and Business.
    Smells: olfactive dimension in designing textile architecture2017Licentiate thesis, monograph (Other academic)
    Abstract [en]

    Designing with non-visual attributes challenges ways of representation. This research explores methods for designing with invisible materiality within the research practice, as well as ways of representation through textiles when designing spaces. Exploring textiles and smells within a space, the research program investigates spatial interactions.

    This research focuses on designing embodied experiences using tangible materials as expressions of smells. Through the spatial installations and performances Sight of smell, Touch of smell, and Smell, space, and body movement, haptics were explored as one of the methods of interaction with smells through textiles.

    Through the sense of touch, this research also investigates ways of revealing, activating, and disseminating smells within a space. Smells were purposely added through the methods of dyeing, coating, and printing to the textile materials that did not inherently embody any smells, As a result, tactile surfaces create non-visual expressions of smell. Further ideas of research in this area would explore another perspective

    of designing with smells in spaces. As an example, by designing textiles being smell absorbers, dividers, and re ectors, could compliment the spatial concepts and deals with the already existing smells in a living environment.

    In this licentiate thesis thinking through the olfactive dimension to design textiles is not only novel for the textile design eld; but also, its proposal for application in the spatial design is quite unique, and o ers a new dimension for spatial design.

  • Public defence: 2017-12-15 13:00 Humanistiska Teatern, Uppsala
    Börjesson, Lisa
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Arts, Department of ALM.
    Resources for scholarly documentation in professional service organizations: A study of Swedish development-led archaeology report writing2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This information studies dissertation deals with the problem that results from research outside academia risk to receive little or no attention if communicated through reports, instead of in mainstream academic genres like research journal articles. The case in focus is Swedish development-led (DL) archaeology, i.e. state regulated archaeology preceding land development. Swedish DL archaeology is organized as a semi-regulated market. The organizations competing on the market are professional service organizations selling research services to land developers. Regional government departments, county administrative boards, function as intermediaries setting up procurement-like processes.

    In previous research on archaeological documentation, the problem with non-use of reports has been described as depending on cultural issues of access, possible to solve if individuals make efforts to communicate and use extra-academic results. This dissertation offers an alternative definition of the problem, highlighting a different set of solutions. The aim is to further the understanding of how the distribution of research duties to professional service organizations affects the scholarly documentation in Swedish archaeology. The aim is met through identification, operationalization and analysis of resources available to report writing DL archaeology practitioners, and an analysis of how practitioners draw on these resources. The results further the understanding of how reports are shaped within the DL archaeology institution. In view of these results, efforts to solve issues of access should target the organization of research in the archaeology discipline, and specifically how scholarly documentation is governed on the archaeology market.

    The dissertation draws on science and technology studies, practice theory, and document theory for the design of the study of documentation resources and contexts in extra-academic research. A mixed methods approach is applied to capture regulative, institutional, and infrastructural resources, and practitioners’ use thereof. Dissertation papers I-III contain analyses of concrete instantiations of the resources: information policy, documentation ideals, and information source use. The fourth paper presents an analysis of how practitioners draw on these resources in their everyday report writing. The dissertation concerns archaeology specifically, but serves as grounds to inquire into the premises for scholarly documentation in other areas of extra-academic research and knowledge-making as well.

  • Public defence: 2017-12-13 09:00 F3, Stockholm
    Fridström, Richard
    KTH, School of Electrical Engineering (EES), Fusion Plasma Physics.
    Resonant magnetic perturbation effect on the tearing mode dynamics: Novel measurements and modeling of magnetic fluctuation induced momentum transport in the reversed-field pinch2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The tearing mode (TM) is a resistive instability that can arise in magnetically confined plasmas. The TM can be driven unstable by the gradient of the plasma current. When the mode grows it destroys the magnetic field symmetry and reconnects the magnetic field in the form of a so-called magnetic island. The TMs are inherent to a type of device called the reversed-field pinch (RFP), which is a device for toroidal magnetic confinement of fusion plasmas. In the RFP, TMs arise at several resonant surfaces, i.e. where the field lines and the perturbation have the same pitch angle. These surfaces are closely spaced in the RFP and the neighboring TM islands can overlap. Due to the island overlap, the magnetic field lines become tangled resulting in a stochastic magnetic field, i.e. the field lines fill a volume instead of lying on toroidal surfaces. Consequently, a stochastic field results in an anomalously fast transport in the radial direction. Stochastic fields can also arise in other plasmas, for example, the tokamak edge when a resonant magnetic perturbation (RMP) is applied by external coils. This stochastization is intentional to mitigate the edge-localized modes. The RMPs are also used for control of other instabilities. Due to the finite number of RMP coils, however, the RMP fields can contain sidebands that decelerate and lock the TMs via electromagnetic torques. The locking causes an increased plasma-wall interaction. And in the tokamak, the TM locking can cause a plasma disruption which is disastrous for future high-energy devices like the ITER. In this thesis, the TM locking was studied in two RFPs (EXTRAP T2R and Madison Symmetric Torus) by applying RMPs. The experiments were compared with modern mode-locking theory. To determine the viscosity in different magnetic configurations where the field is stochastic, we perturbed the momentum via an RMP and an insertable biased electrode.

    In the TM locking experiments, we found qualitative agreement with the mode-locking theory. In the model, the kinematic viscosity was chosen to match the experimental locking instant. The model then predicts the braking curve, the short timescale dynamics, and the mode unlocking. To unlock a mode, the RMP amplitude had to decrease by a factor ten from the locking amplitude. These results show that mode-locking theory, including the relevant electromagnetic torques and the viscous plasma response, can explain the experimental features. The model required viscosity agreed with another independent estimation of the viscosity. This showed that the RMP technique can be utilized for estimations of the viscosity.

    In the momentum perturbation experiments, it was found that the viscosity increased 100-fold when the magnetic fluctuation amplitude increased 10-fold. Thus, the experimental viscosity exhibits the same scaling as predicted by transport in a stochastic magnetic field. The magnitude of the viscosity agreed with a model that assumes that transport occurs at the sound speed -- the first detailed test of this model. The result can, for example, lead to a clearer comparison between experiment and visco-resistive magnetohydrodynamics (MHD) modeling of plasmas with a stochastic magnetic field. These comparisons had been complicated due to the large uncertainty in the experimental viscosity. Now, the viscosity can be better constrained, improving the predictive capability of fusion science.

  • Public defence: 2017-12-12 10:00 B1, Stockholm
    Kellner, Hans
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Applied Process Metallurgy.
    Study of Non-metallic Inclusion in Alloy 8252017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    It is well known that inclusions affect the properties of steels and alloys. Therefore, it is important to understand what type of inclusions that exist and how they behave and especially with a focus on large size inclusions. Thus, the large size non-metallic inclusions in ferroalloy FeTi70R were investigated in two dimensions (2D) by using scanning electron microscopy (SEM) in combination with an energy dispersive technique (EDS). It was found that the FeTi70R ferroalloy contain complex oxide inclusions consisting mostly of CaO, SiO2 and TiOx. Furthermore, experimental trials were performed to investigate how these inclusions behaved when entering a melt. More specifically, a comparison between pure Fe and an Alloy 825 grade were made. These results determined the parameters effect on the transformation of the inclusions in the melt.

    The large size non-metallic inclusions in Alloy 825 during the ladle treatment were investigated during industrial trials by using both two dimensional (2D) and three dimensional (3D) microscopic investigations. The results showed that inclusions consisted of spherical oxides and clusters made up of oxides and nitrides. Further investigations found that the spherical inclusions were transformed from existing NMI in the FeTi70R ferroalloy and slag particles. As for the clusters, they originate from deoxidation products. Furthermore, small inclusions precipitated in the local zones around the added FeTi70R ferroalloy and titanium nitrides. Investigations also found that only Al2O3-MgO and TiN clusters exist after casting.

    Industrial trials were performed during the last period of the ladle treatment and using a combined electromagnetic (EMS) and gas (GS) stirring. The purpose to investigate the effect of different EMS directions on the agglomeration and on the removal of Al2O3-MgO and TiN clusters. The investigations were then performed in 3D after an electrolytic extraction of the metal samples. The results show that electromagnetic stirring in the upwards direction is best for the agglomeration of the Al2O3-MgO and TiN clusters. However, electromagnetic stirring in the downwards direction is more effective to remove clusters from the melt. This is in agreement with the theoretical predictions based on Stokes’, Brownian and Turbulent collisions. Also, the calculations showed that for Al2O3-MgO clusters with sizes <20 μm the Turbulent collision is the defining factor for agglomeration. However, both Stokes’ and Turbulent collisions are dominant for larger inclusions. For the TiN clusters, turbulent collisions is the dominant factor.

    Further investigations with more heats and stirring modes were done by using 2D microscopic investigations. More specifically, the number, size, composition and morphology of different inclusions were determined by using SEM in combination with EDS and Inca Feature analyses. The results show that the EMS in downwards direction with a 0.04 m3 min-1 gas flow rate promotes a general removal of Al2O3-MgO and TiN inclusions. Furthermore, that the upwards EMS direction promotes a drastically increase of inclusions having an equivalent size smaller than 11.2 μm. Moreover, the stirring with a 0.02 m3 min-1 gas flow rate has a better removal rate for both downwards and upwards stirring directions compared to the stirring with a 0.04 m3 min-1 gas flow rate. However, no influence on the inclusion composition and morphology could be seen from the different stirring modes.

  • Public defence: 2017-12-15 13:15 ITC 2446, Uppsala
    Francisco Rodríguez, María Andreína
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Computing Science. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Computing Science.
    Analysis, synthesis and application of automaton-based constraint descriptions2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Constraint programming (CP) is a technology in which a combinatorial problem is modelled as a conjunction of constraints on variables ranging over given initial domains, and optionally an objective function on the variables. Such a model is given to a general-purpose solver performing systematic search to find constraint-satisfying domain values for the variables, giving an optimal value to the objective function. A constraint predicate (also known as a global constraint) does two things: from the modelling perspective, it allows a modeller to express a commonly occurring combinatorial substructure, for example that a set of variables must take distinct values; from the solving perspective, it comes with a propagation algorithm, called a propagator, which removes some but not necessarily all impossible values from the current domains of its variables when invoked during search.

    Although modern CP solvers have many constraint predicates, often a predicate one would like to use is not available. In the past, the choices were either to reformulate the model or to write one's own propagator. In this dissertation, we contribute to the automatic design of propagators for new predicates.

    Integer time series are often subject to constraints on the aggregation of the features of all maximal occurrences of some pattern. For example, the minimum width of the peaks may be constrained. Automata allow many constraint predicates for variable sequences, and in particular many time-series predicates, to be described in a high-level way. Our first contribution is an algorithm for generating an automaton-based predicate description from a pattern, a feature, and an aggregator.

    It has previously been shown how to decompose an automaton-described constraint on a variable sequence into a conjunction of constraints whose predicates have existing propagators. This conjunction provides the propagation, but it is unknown how to propagate it efficiently. Our second contribution is a tool for deriving, in an off-line process, implied constraints for automaton-induced constraint decompositions to improve propagation. Further, when a constraint predicate functionally determines a result variable that is unchanged under reversal of a variable sequence, we provide as our third contribution an algorithm for deriving an implied constraint between the result variables for a variable sequence, a prefix thereof, and the corresponding suffix.

  • Public defence: 2017-12-15 13:00 William-Olssonsalen, Geovetenskapens hus, Stockholm
    Dahl, Martin
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Natural and human-induced carbon storage variability in seagrass meadows2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Seagrasses are considered highly important CO2 sinks, with the capacity to store substantial quantities of organic carbon in the living biomass and sediments, and thereby acting as a buffer against climate change. In this thesis, I have studied carbon storage variability in temperate and tropical seagrass habitats and identified factors influencing this variation. In addition, as seagrass areas are decreasing worldwide, I have assessed effects of different anthropogenic disturbances on carbon sequestration processes. The result from this thesis showed that there was a large variation in carbon storage within and among temperate, tropical and subtropical regions. The highest organic carbon stocks were found in temperate Zostera marina meadows, which also showed a larger carbon storage variability than the subtropical and tropical seagrass habitats. The tropical and subtropical seagrass meadows had inorganic carbon pools exceeding the organic carbon accumulation, which could potentially weakens the carbon sink function. The variability in organic carbon stocks was generally strongly related to the sediment characteristics of the seagrass habitats. In Z. marina meadows, the strength of the carbon sink function was mainly driven by the settings of the local environment, which in turn indicates that depositional areas will likely have higher organic carbon stocks than more exposed meadows, while in the tropics seagrass biomass was also influencing sedimentary carbon levels. Furthermore, locations with large areas of seagrass were associated with higher carbon storage in tropical and subtropical regions, which could be related to increased accumulation of both autochthonous and allochthonous carbon. In an in situ experiment, impacts on carbon sequestration processes from two types of disturbances (with two levels of intensity) were tested by simulating reduced water quality (by shading) and high grazing pressure (through removal of shoot biomass). At high disturbance intensity, reductions in the net community production and seagrass biomass carbon were observed, which negatively affected carbon sequestration and could impact the sedimentary organic carbon stocks over time. In the treatments with simulated grazing, erosion was also seen, likely due to an increase in near-bed hydrodynamics. When experimentally testing effects of increased current flow on organic carbon suspension in Z. marina sediment, a ten-fold release of organic carbon with higher current flow velocities was measured, which resulted in an increase in the proportion of suspended organic carbon by three times in relation to other sediment particles. Therefore, periods with enhanced hydrodynamic activity could result in a removal of organic carbon and thereby likely reduce the seagrass meadows’ capacity to store carbon. The findings of this thesis add to the emerging picture that there is a large natural variability in seagrasses’ capacity to store carbon, and highlight how human-induced disturbances could negatively affect the carbon sink function in seagrass meadows.

  • Public defence: 2017-12-15 13:00 Vivi Täckholmsalen (Q-salen), NPQ-huset, Stockholm
    Corral López, Alberto
    Stockholm University, Faculty of Science, Department of Zoology.
    The link between brain size, cognitive ability, mate choice and sexual behaviour in the guppy (Poecilia reticulata)2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Competition over access for mates has led to the evolution of many striking examples of morphological traits and behaviour in animals. The rapid development of the sexual selection field in recent decades have dramatically advanced our understanding of what traits make individuals more successful in attracting mates and how preferences for mates evolve over time. However, till now, research in this field has put less emphasis on the mechanisms that underlie variation in mate choice and sexual behaviour. Cognitive processes could potentially be key drivers of individual variation in mating preferences and sexual behaviours and therefore deserve further investigation. In this thesis, I used guppies artificially selected for relative brain size as the model system to study the association between brain size, cognitive ability and various aspects of mate choice. Previous studies in this model system showed that large-brained individuals of both sexes outperformed small-brained individuals in cognitive tests. Here I quantified their sexual behaviours and mating preferences to provide novel empirical data concerning the association between brain size, cognitive ability and sexual selection. In dichotomous choice preference tests based on visual cues, comparisons between large-brained and small-brained guppies showed important differences in their assessment of mate quality. These results are not driven by pre-existing visual biases caused by the artificial selection since further investigation of the visual capacity of these fish detected no differences between large-brained and small-brained individuals in their sensitivity to colour or in their capacity to resolve spatial detail. I also quantified sexual behaviour in male guppies artificially selected for relative brain size and found no difference in the behaviours of large-brained and small-brained males in a single male-single female non-competitive scenario. On the contrary, in a more complex social setting I found a reduction in large-brained males in the rate of courtship towards females and dominance displays towards other males when exposed to different degrees of predation threat and different numbers of male competitors. However, this reduction in behavioural intensity did not result in a lower access to copulation with females for large-brained males. I likewise evaluated female sexual behaviour and found that large-brained females had higher behavioural flexibility such that they decreased their receptiveness towards males more strongly under higher levels of predation threat. Together, these results provide novel empirical evidence that brain size and cognitive ability are tightly linked to mating preferences and sexual behaviours. These findings suggest that brain size and cognitive ability might be important mechanisms behind variation in mating preferences and in sexually selected traits across and within species.

  • Public defence: 2017-12-15 09:30 Vivi Täckholmsalen (Q-salen), NPQ-huset, Stockholm
    Kanatani, Sachie
    Stockholm University, Faculty of Science, Department of Molecular Biosciences, The Wenner-Gren Institute.
    Host-parasite interactions in the dissemination of Toxoplasma gondii2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Toxoplasma gondii is an obligate intracellular parasite that infects virtually all warm-blooded organisms. Systemic dissemination of T. gondii in the organism can cause life-threatening infection that manifests as Toxoplasma encephalitis in immune-compromised patients. In addition, mounting evidence from epidemiological studies indicates a link between chronic Toxoplasma infection and mental disorders. To better understand the pathogenesis of toxoplasmosis, basic knowledge on the host-parasite interactions and the dissemination mechanisms are essential. Previous findings have established that, upon infection with T. gondii, dendritic cells (DCs) and microglia exhibit enhanced migration, which was termed the hypermigratory phenotype. As a result of this enhanced migration, DCs and microglia are used as vehicle cells for dissemination (‘Trojan horse’) which potentiates dissemination of T. gondii in mice. However, the precise mechanisms behind the hypermigratory phenotype remained unknown. In this thesis, we characterized host-parasite interactions upon infection with T. gondii and investigated the basic mechanisms behind the hypermigratory phenotype of T. gondii-infected DCs and microglia.

    In paper I, we observed that upon infection with T. gondii, DCs underwent rapid morphological changes such as loss of adhesiveness and podosomes, with integrin redistribution. These rapid morphological changes were linked to hypermotility and were induced by active invasion of T. gondii within minutes. T. gondii-infected DCs exhibited up-regulation of the C-C chemokine receptor CCR7 and chemotaxis towards the CCR7 chemotactic cue, CCL19.

    In paper II, we developed a 3-dimensional migration assay in a collagen matrix, which allowed us to characterize the hypermigratory phenotype in a more in vivo-like environment. The migration of T. gondii-infected DCs exhibited features consistent with integrin-independent amoeboid type of migration. T. gondii-induced hypermigration of DCs was further potentiated in the presence of CCL19 in a 3D migration assay.

    In paper III, we identified a parasite effector molecule, a Tg14-3-3 protein derived from parasite secretory organelles. Tg14-3-3 was sufficient to induce the hypermigratory phenotype. Transfection with Tg14-3-3-containing fractions or recombinant Tg14-3-3 protein induced the hypermigratory phenotype in primary DCs and in a microglial cell line. In addition, Tg14-3-3 localized in the parasitophorous vacuolar space and host 14-3-3 proteins were rapidly recruited around the parasitophorous vacuole.

    In paper IV, we found that mouse DCs dominantly express the L-type voltage-dependent calcium channel, Cav1.3. Cav1.3 was linked to the GABAergic signaling-induced hypermigratory phenotype. Pharmacological inhibition of Cav1.3 and knockdown of Cav1.3 abolished the hypermigratory phenotype in T. gondii infected DCs. Blockade of voltage-dependent calcium channels reduced the dissemination of T. gondii in a mouse model.

    In paper V, we showed that microglia, resident immune cells in the brain, also exhibited rapid morphological changes and hypermotility upon infection with T. gondii. However, an alternative GABA synthesis pathway was shown to be involved in the hypermigratory phenotype in microglia.

    In summary, this thesis describes novel host-parasite interactions, including host cell migratory responses and key molecular mechanisms that mediate the hypermigratory phenotype. The findings define a novel motility-related signaling axis in DCs. Thus, T. gondii employs GABAergic non-canonical pathways to hijack host cell migration and facilitate dissemination. We believe that these findings represent a significant step forward towards a better understanding of the pathogenesis of T. gondii infection.

  • Public defence: 2017-12-15 10:00 sal G Arrheniuslaboratorierna, Stockholm
    Boguslaw, Julia
    Stockholm University, Faculty of Social Sciences, Department of Economics.
    When the Kids Are Not Alright: Essays on Childhood Disadvantage and Its Consequences2017Doctoral thesis, monograph (Other academic)
    Abstract [en]

    This thesis consists of three self-contained essays on childhood disadvantage and its consequences in Sweden.

    A Longitudinal Look at Child Poverty Using Both Monetary and Non-monetary Approaches. In this paper, we broaden the analysis of child poverty by using both monetary and non-monetary measures of poverty and by comparing these over time. We use a composite of questionnaire answers from children regarding possession of socially perceived necessities and participation in social activities to develop two non-monetary child-centric concepts of disadvantage: material deprivation and social exclusion. The empirical analysis is based on two cross-sections and a panel of children in the Swedish Level-of-Living Survey matched with parental survey data and administrative income records. Consistent with previous findings, we find that relative income poverty among children increases significantly between the year 2000 and 2010. The fraction of children that is disadvantaged in two dimensions, monetary and non-monetary, is relatively small (0.9–7.0 percent) but increases significantly during the period of study. The modest size of the overlap suggests that our measures capture different dimensions of disadvantage, thereby pointing to the importance of alternative poverty indicators. We also find that income status in childhood is the best predictor of socio-economic outcomes in young adulthood.

    The Aspirations-attainment Paradox of Immigrant Children: A Social Networks Approach. Using two independent and nationally representative samples of Swedish children, I compare the university aspirations and expectations between children of immigrants and children of natives. In line with existing findings, I find that children with foreign-born parents have significantly higher aspirations and expectations than their native-majority peers with and without conditioning on school performance, academic potential and friendship networks. I do not find any evidence of a significant immigrant-non-immigrant aspirations-expectations gap; immigrant children's aspirations and expectations are not less aligned than those of their native-majority peers. This result suggests that immigrant-native disparities in school outcomes are not driven by an aspirations-expectations gap. Finally, the results reveal significant gender differences. Native-majority girls with academic potential are, for example, more likely to express an aspirations-expectations gap. Moreover, having only female friends makes one less likely to belong to the aforementioned category.

    The Key Player in Disruptive Behavior: Whom Should We Target to Improve the Classroom Learning Environment? In this paper, I address the question: Who is the individual that exerts the greatest negative influence on the classroom learning environment? To answer this question, I invoke the key player model from network economics and use self-reported friendship data in order to solve the methodological problems associated with identifying and estimating peer effects. I overcome the issue of endogenous group formation by using the control function approach where I simultaneously estimate network formation and outcomes. The results show that the typical key player scores well on language and cognitive ability tests and is not more likely to be a boy than a girl. I also find evidence that removing the key player has a significantly larger effect on aggregate disruptiveness in a network than removing the most disruptive individual, implying that policy aimed at the most active individual could be inadequate.

  • Public defence: 2017-12-16 13:00 Nordenskiöldsalen Geovetenskapens hus, Stockholm
    Cooper, Andrew
    Stockholm University, Faculty of Humanities, Department of English.
    A unified account of the Old English metrical line2017Doctoral thesis, monograph (Other academic)
    Abstract [en]

    This study describes the verse design of Old English poetry in terms of modern phonological theory, developing an analysis which allows all OE verse lines to be described in terms of single metrical design.

    Old English poetry is typified by a single type of line of variable length, characterised by four metrical peaks. The variation evident in the lengths of OE metrical units has caused previous models to overgenerate acceptable verse forms or to develop complex typologies of dozens of acceptable forms. In this study, Metrical phonology and Optimality theory are used to highlight some aspects of the relationship between syntax, phonology and verse metrics in determining how sentences and phrases interact with the verse structure to create variation.

    The main part of the study is a metrical model based on the results of a corpus analysis. The corpus is centred on the OE poems Genesis and Andreas, complemented by selected shorter poems. A template of a prototypical line is described based on a verse foot which contains three vocalic moras, and which can vary between 2 and 4 vocalic moras distributed across 1 to 4 syllables. Each standard line is shown to consist of four of these verse feet, leading to a line length which can vary between 8 and 16 vocalic moras. It is shown that the limited variation within the length of the verse foot causes the greater variation in the length of lines. The rare, longer ‘hypermetric’ line is also accounted for with a modified analysis. The study disentangles the verse foot, which is an abstract metrical structure, from the prosodic word, which is a phonological object upon which the verse foot is based, and with which it is often congruent. Separate sets of constraints are elaborated for creating prosodic words in OE, and for fitting them into verse feet and lines. The metrical model developed as a result of this analysis is supported by three smaller focused studies.

    The constraints for creating prosodic words are defended with reference to compounds and derivational nouns, and are supported by a smaller study focusing on the metrical realisation of non-Germanic personal names in OE verse. Names of biblical origin are often longer than the OE prosodic word can accommodate. The supporting study on non-Germanic names demonstrates how long words with no obvious internal morphology in OE are adapted first to OE prosody and then to the verse structure. The solution for the metrical realisation of these names is shown to be patterned on derivational nouns.

    The supporting study on compound numerals describes how phrases longer than a verse are accommodated by the verse design. It is shown that compound numerals, which consist of two or more numeral words (e.g. 777 – seofonhund and seofon and hundseofontig) are habitually rearranged within the text to meet the requirements of verse length and alliteration.

    A further supporting study discusses the difference between the line length constraints controlling OE verse design and those for Old Norse and Old Saxon verse. Previous studies have often conflated these three closely related traditions into a single system. It is shown that despite their common characteristics, the verse design described in this study applies to all OE verse, but not to ON or OS.

  • Public defence: 2017-12-15 13:00 sal FA32 AlbaNova universitetscentrum, Stockholm
    Bertoli, Gabriele
    Stockholm University, Faculty of Science, Department of Physics.
    Search for Supersymmetry and Large Extra Dimensions with the ATLAS Experiment2017Doctoral thesis, monograph (Other academic)
    Abstract [en]

    The Large Hadron Collider is the most powerful particle accelerator built to date. It is a proton-proton and heavy ion collider which in 2015 and 2016 operated at an unprecedented center of mass energy of √s = 13 TeV. The Tile Calorimeter is the ATLAS hadronic calorimeter covering the central region of the detector. It is designed to measure hadrons, jets, tau particles and missing energy. In order to accurately be able to properly reconstruct these physical objects a careful description of the electronic noise is required. This thesis presents the work done in updating, monitoring and studying the noise calibration constants used in the processing and identication of hadronic jet in the 2011 data.

    Moreover the results of the searches for compressed supersymmetric squark-neutralino and large extra dimensions models are also presented in this thesis. The present work uses an experimental signature with a high energy hadronic jet and large missing transverse energy later often referred to as monojet signature. The search for supersymmetry is carried out using an integrated luminosity of 3.2 fb-1 recorded by the ATLAS experiment in 2015.

    The search for large extra dimensions presented in this work uses the full 2015 + 2016 dataset of 36.1 fb-1. No signicant excess compared to the Standard Model prediction has been observed on the production of squark pairs with the subsequent decay of the squark in a quark and a neutrino. Exclusion limits are set on squark production as a function of the neutralino mass. Squark masses up to 608 GeV are excluded for a mass difference between the squark and the neutralino of 5 GeV. In the second search for the presence of large extra spatial dimensions in the Arkani-Hamed, Dimopoulos and Dvali model scenario a good agreement between data and Standard Model prediction is observed and exclusion limits are set on the effective Planck scale MD of 7.7 and 4.8 TeV for two and six hypothesized large extra dimensions respectively signicantly improving earlier results.

  • Public defence: 2017-12-15 13:00 Högbomsalen, Geovetenskapens hus, Stockholm
    Marklund, Ellen
    Stockholm University, Faculty of Humanities, Department of Linguistics.
    Perceptual reorganization of vowels: Separating the linguistic and acoustic parts of the mismatch response2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    During the first year of life, infants go from perceiving speech sounds primarily based on their acoustic characteristics, to perceiving speech sounds as belonging to speech sound categories relevant in their native language(s). The transition is apparent in that very young infants typically discriminate both native and non-native speech sound contrasts, whereas older infants show better discrimination for native contrasts and worse or no discrimi­na­tion for non-native contrasts. The rate of this perceptual reorganization depends, among other things, on the salience of the relevant speech sounds within the speech signal. As such, the perceptual reorganization of vowels and lexical tone typically precedes the perceptual reorganization of consonants.

    Perceptual reorganizatoin of speech sounds is often demonstrated by measuring in­fants’ discrimination of specific speech sound contrasts across development. One way of measuring discriminatory ability is to use the mismatch response (MMR). This is a brain response that can be measured using external electroencephalography re­cord­ings. Pre­senting an oddball (deviant) stimulus among a series of standard stimuli elicits a response that, in adults, correlates well with behavioral discrimination. When the two stimuli are speech sounds contrastive in the listeners’ language, the response arguably reflects both acoustic and linguistic processing. In infants, the response is less studied, but has nevertheless already proven useful for studies on the perceptual reorganization of speech sounds.

    The present thesis documents a series of studies with the end game of investigating how amount of speech exposure influences the perceptual reorganization, and whe­ther the learning mechanisms involved in speech sound cate­gory learning is specific to speech or domain-general. In order to be able to compare MMR results across diffe­rent age groups in infancy, a non-speech control condition needed to be devised however, to account for changes in the MMR across development that are attributable to general brain matura­tion rather than language development specifically.

    Findings of studies incorporated in the thesis show that spectrally rotated speech can be used to approximate the acoustic part of the MMR in adults. Subtracting the acoustic part of the MMR from the full MMR thus estimates the part of the MMR that is linked to linguistic, rather than acoustic, processing. The strength of this linguistic part of the MMR in four- and eight-month-old infants is directly related to the daily amount of speech that the infants are exposed to. No evidence of distributional learning of non-speech auditory categories was demonstrated in adults, but the results together with previous research generated hypo­theses for future study.

    In conclusion, the research performed within the scope of this thesis highlight the need of a non-speech control condition for use in developmental speech perception studies using the MMR, demonstrates the viability of one such non-speech control condition, and points toward relevant future research within the topic of speech sound category development.

  • Public defence: 2017-12-15 10:00 rum 207, Stressforskningsinstitutet, Stockholm
    Schiller, Helena
    Stockholm University, Faculty of Social Sciences, Centre for Health Equity Studies (CHESS).
    How to work for a good night's sleep2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Stress and sleep problems are common in the working population and cause considerable costs for society. Sleep is the most important part of recovery, and poor sleep has a negative impact on overall functioning, which might have important consequences for both the employee, the employer and society. In order to find strategies to alleviate this contemporary public health concern of stress and poor sleep in the working population, this thesis evaluated interventions performed at the workplace to target these issues.

    The first intervention is a randomized controlled trial of a 25% work time reduction for full-time workers within the public sector in Sweden. Study I evaluated the impact of work time reduction on subjective sleep quality, sleep duration, sleepiness, perceived stress, and bedtime worries. Assessments included diary data from one week at three occasions over 18 months. Study II investigated time-use patterns through activity reporting sheets used during the work time reduction by evaluating the amount of total workload, paid work, non-paid work and recovery activities. Both studies investigated workdays and days off separately as well as the importance of gender, family status and work situation (only Study II). The second randomized controlled intervention of the thesis is a group cognitive behavioral therapy (CBT) intervention at the workplace targeting sleep disturbances among employees within the retail sector in Sweden (Study III). Data were collected through questionnaires, diaries and objective sleep measurement (actigraphy) over a period of ten days before and after the intervention, as well as at a three-month follow up. The study evaluated the effects of the intervention on sleep and explored the moderating effect of burnout-levels at baseline.

    In our studies, an economically fully compensated reduction of work hours for full-time workers lead to long-term positive effects on sleep duration and sleep quality, sleepiness and levels of perceived stress. During this work time reduction, the total workload of both paid and non-paid work was reduced and time spent in recovery activities increased. The results indicate that a more balanced relation between effort and recovery was established. The second intervention, which targets the individual through a group CBT-intervention for insomnia at the workplace, was shown to improve insomnia symptoms in daytime workers who did not suffer from concurrent burnout. Such an intervention could support the individual in handling sleep problems and preventing the development of more severe and chronic sleep disorders, as opposed to interventions aimed at making environmental changes at the workplace. However, the CBT-intervention evaluated within this thesis will need to be further developed in order to be beneficial for more groups of employees. The positive effects of these interventions might be beneficial for public health and help improve employee’s life satisfaction, daily functioning and health development.​

  • Public defence: 2017-12-15 15:00 De Geersalen Geovetenskapens hus, Stockholm
    Cao, Mengyi
    Stockholm University, Faculty of Social Sciences, Department of Economics.
    Labor, Trade and Finance: Essays in Applied Economics2017Doctoral thesis, monograph (Other academic)
    Abstract [en]

    Essay I: Credit Constraint and College Attendance. 

    This paper shows that housing wealth alleviate credit constraints for potential college attendees by enabling home owners to extract equity from their property and invest it in the education. Using a large US individual-level survey dataset over the 1996-2011 period, I find that one standard deviation increases of housing prices translate into approximately 72,000 more students enrolled in college each year. My results stay significant when I use proxies for aggregate housing demand shocks and for the topological elasticity of housing supply to generate variation in home equity that is assumed to be orthogonal to decision of going to college.

    Essay II: Income Inequality and Trade.

    Does trade with unskilled labor-abundant countries reduce the relative wages of U.S. unskilled labor and consequently cause increased income inequality across industries and regions? Empirical studies in the 1990s found only a modest effect. In this paper, I re-consider the question by using the income inequality measures constructed from Current Population Survey (CPS) data and analyzing the effect of rising Chinese import competition between 1993 and 2007 on US local labor markets. I find that areas which are more exposed to China imports competition have larger changes in income inequality. In my main specification, a $1,000 exogenous decadal rise in a MSA's import exposure per worker leads to a 1.5% increase in the logistic Gini. This re-distributive effect is more profound among non-college educated workers in manufacturing sectors. 

    Essay III: Employee as Creditor: Evidence from Defined Pension Plans.

    In this paper, I show the role of pension plans in shaping the firms' labor market decision. By employing the loan covenants violation and consequently transferring of control rights to creditors, I examine the strategic use of pension underfunding by firms and the resultant wage cuts. I also find that the wage concession is less severe for firms from industry with bigger bargaining power. This study sheds light on how firms strategically renegotiate labor contracts to extract concessions from labor. The evidence suggests that credit contracts between debt-holders and shareholders have spillover effects on non-financial stakeholders. 

  • Public defence: 2017-12-15 14:30 V3, Stockholm
    Boström, Erik
    KTH, School of Engineering Sciences (SCI), Mechanics, Stability, Transition and Control.
    Boundary Conditions for Spectral Simulations of Atmospheric Boundary Layers2017Licentiate thesis, monograph (Other academic)
  • Aaboud, M.
    et al.
    Bergeås Kuutmann, Elin
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, High Energy Physics.
    Bokan, Petar
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, High Energy Physics.
    Brenner, Richard
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, High Energy Physics.
    Ekelöf, Tord
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, High Energy Physics.
    Ellert, Mattias
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, High Energy Physics.
    Ferrari, Arnaud
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, High Energy Physics.
    Gradin, P. O. Joakim
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, High Energy Physics.
    Isacson, Max
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, High Energy Physics.
    Mårtensson, Mikael
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, High Energy Physics.
    Öhman, Henrik
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, High Energy Physics.
    Rangel Smith, Camila
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, High Energy Physics.
    De Bruin, Pedro Sales
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, High Energy Physics.
    Zwalinski, L.
    Search for direct top squark pair production in events with a Higgs or Z boson, and missing transverse momentum in root s=13 TeV pp collisions with the ATLAS detector2017In: Journal of High Energy Physics (JHEP), ISSN 1126-6708, E-ISSN 1029-8479, no 8, 006Article in journal (Refereed)
    Abstract [en]

    A search for direct top squark pair production resulting in events with either a same-flavour opposite-sign dilepton pair with invariant mass compatible with a Z boson or a pair of jets compatible with a Standard Model (SM) Higgs boson (h) is presented. Requirements on the missing transverse momentum, together with additional selections on leptons, jets, jets identified as originating from b-quarks are imposed to target the other decay products of the top squark pair. The analysis is performed using proton-proton collision data at root s = 13 TeV collected with the ATLAS detector at the LHC in 20152016, corresponding to an integrated luminosity of 36.1 fb(-1). No excess is observed in the data with respect to the SM predictions. The results are interpreted in two sets of models. In the first set, direct production of pairs of lighter top squarks ((t) over tilde (1)) with long decay chains involving Z or Higgs bosons is considered. The second set includes direct pair production of the heavier top squark pairs ((t) over tilde (2)) decaying via (t) over tilde (2) -> Z (t) over tilde (1) or (t) over tilde (2) -> h (t) over tilde (1). The results exclude at 95% confidence level (t) over tilde (2) and (t) over tilde (1) masses up to about 800 GeV, extending the exclusion region of supersymmetric parameter space covered by previous LHC searches.

  • Public defence: 2017-12-18 14:00 D3, Stockholm
    Khoshkar, Sara
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Sustainability Assessment and Management.
    Paving the way for green qualities in urban development-Role of Environmental Assessment2017Licentiate thesis, monograph (Other academic)
    Abstract [en]

    Implementing urban development projects in planning practice while simultaneously providing sufficient green spaces has proven to be challenging. As a result, there is a growing need for practical approaches and tools for the integration of urban green qualities in the on-going densification of cities. Environmental assessment, as a proactive decision aiding tool, can hold an important role in integrating green qualities in urban development plans and projects. However, in recent years environmental assessment has only added moderate value to planning issues regarding green space. Therefore, this thesis was designed to contribute to the knowledge and understanding on the role environmental assessment can have in the integration of green qualities in future urban development plans and projects in efforts to aid practitioners. This aim was achieved through examination of existing urban green space planning practice in the Stockholm region (Paper I) and the practice of environmental assessment in a selection of European countries in relation to the following factors identified to be important for practice: timing, quality control, alternatives, monitoring and public participation (Paper II). The findings from both studies were then analysed to identify possibilities of green space planning within the framework of these factors. A qualitative research was employed for this study including: semi-structured interviews with municipal planners in the Stockholm region and environmental assessment experts for the European Commission, literature review, document analysis and case study analysis. The case studies analyzed in Paper I were located in municipalities of Haninge and Huddinge, suburban areas located to the south of Stockholm. In Paper II, the experts interviewed were environmental assessment experts from the European Commission from: Austria, Denmark, Finland, Greece, Luxembourg, the Netherlands, Norway and Slovenia. Through analysis of the results from both studies, the potential role of environmental assessment in integrating green qualities in urban development plans and projects are explored and discussed in relation to the factors. The potential of environmental assessment to enhance public participation and dialogues amongst actors, or bring forth green space issues within alternatives are a few of the roles discussed. Furthermore, a selection of pathways is suggested for the integration of green qualities in future urban development through the application of environmental assessment. For example, the implementation of developer dialogues in the environmental assessment process and the development of knowledge exchange platforms for sharing experiences in relation to green space planning and environmental assessment.

  • Kiruja, Jonah
    et al.
    Faculty of Nursing and Midwifery, Hargeisa, Somaliland.
    Osman, Fatumo
    Dalarna University, School of Education, Health and Social Studies, Caring Science/Nursing.
    Ali Egal, Jama
    Faculty of Nursing and Midwifery, Hargeisa University, Somaliland.
    Klingberg-Allvin, Marie
    Dalarna University, School of Education, Health and Social Studies, Caring Science/Nursing.
    Malm, Mari-Cristin
    Dalarna University, School of Education, Health and Social Studies, Caring Science/Nursing.
    Erlandsson, Kerstin
    Dalarna University, School of Education, Health and Social Studies, Caring Science/Nursing.
    Risk Factors for Stillbirth and Beliefs: Findings from a Pilot near Miss Questionnaire Study in Somaliland Focusing the Mother-Baby Dyad2017In: MOJ Women's Health, ISSN ?, Vol. 5, no 3, 1-9 p., 00123Article in journal (Refereed)
  • Ingole, Vijendra
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Epidemiology and Global Health. Umeå University, Faculty of Social Sciences, Centre for Demographic and Ageing Research (CEDAR). Vadu Rural Health Program, KEM Hospital Research Centre, Pune 411011, India; INDEPTH Network, Accra, Ghana.
    Kovats, Sari
    Schumann, Barbara
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Epidemiology and Global Health. Umeå University, Faculty of Social Sciences, Centre for Demographic and Ageing Research (CEDAR).
    Hajat, Shakoor
    Rocklöv, Joacim
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Epidemiology and Global Health.
    Juvekar, Sanjay
    Armstrong, Ben
    Socioenvironmental factors associated with heat and cold-related mortality in Vadu HDSS, western India: a population-based case-crossover study2017In: International journal of biometeorology, ISSN 0020-7128, E-ISSN 1432-1254, Vol. 61, no 10, 1797-1804 p.Article in journal (Refereed)
    Abstract [en]

    Ambient temperatures (heat and cold) are associated with mortality, but limited research is available about groups most vulnerable to these effects in rural populations. We estimated the effects of heat and cold on daily mortality among different sociodemographic groups in the Vadu HDSS area, western India. We studied all deaths in the Vadu HDSS area during 2004-2013. A conditional logistic regression model in a case-crossover design was used. Separate analyses were carried out for summer and winter season. Odds ratios (OR) and 95% confidence intervals (CI) were estimated for total mortality and population subgroups. Temperature above a threshold of 31 A degrees C was associated with total mortality (OR 1.48, CI = 1.05-2.09) per 1 A degrees C increase in daily mean temperature. Odds ratios were higher among females (OR 1.93; CI = 1.07-3.47), those with low education (OR 1.65; CI = 1.00-2.75), those owing larger agricultural land (OR 2.18; CI = 0.99-4.79), and farmers (OR 1.70; CI = 1.02-2.81). In winter, per 1 A degrees C decrease in mean temperature, OR for total mortality was 1.06 (CI = 1.00-1.12) in lag 0-13 days. High risk of cold-related mortality was observed among people occupied in housework (OR = 1.09; CI = 1.00-1.19). Our study suggests that both heat and cold have an impact on mortality particularly heat, but also, to a smaller degree, cold have an impact. The effects may differ partly by sex, education, and occupation. These findings might have important policy implications in preventing heat and cold effects on particularly vulnerable groups of the rural populations in low and middle-income countries with hot semi-arid climate.

  • Fridström, Richard
    et al.
    KTH, School of Electrical Engineering (EES), Fusion Plasma Physics.
    Brunsell, Per
    KTH, School of Electrical Engineering (EES), Fusion Plasma Physics.
    Setiadi, Agung Chris
    Frassinetti, Lorenzo
    KTH, School of Electrical Engineering (EES), Fusion Plasma Physics.
    Multiple-harmonics RMP effect on tearing modes in EXTRAP T2R2017Conference paper (Other academic)
  • Garousi, Javad
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology.
    Andersson, Ken G.
    KTH Royal Inst Technol, Dept Prot Technol.
    Dam, Johan H.
    Odense Univ Hosp, Dept Nucl Med.
    Olsen, Birgitte B.
    Odense Univ Hosp, Dept Nucl Med..
    Mitran, Bogdan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Division of Molecular Imaging.
    Orlova, Anna
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Medicinal Chemistry, Division of Molecular Imaging.
    Buijs, Jos
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology, Medical Radiation Science.
    Ståhl, Stefan
    KTH Royal Inst Technol, Dept Prot Technol.
    Löfblom, John
    KTH Royal Inst Technol, Dept Prot Technol.
    Thisgaard, Helge
    Odense Univ Hosp, Dept Nucl Med.
    Tolmachev, Vladimir
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology.
    The use of radiocobalt as a label improves imaging of EGFR using DOTA-conjugated Affibody molecule2017In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 7, 5961Article in journal (Refereed)
    Abstract [en]

    Several anti-cancer therapies target the epidermal growth factor receptor (EGFR). Radionuclide imaging of EGFR expression in tumours may aid in selection of optimal cancer therapy. The In-111-labelled DOTA-conjugated Z(EGFR:2377) Affibody molecule was successfully used for imaging of EGFR-expressing xenografts in mice. An optimal combination of radionuclide, chelator and targeting protein may further improve the contrast of radionuclide imaging. The aim of this study was to evaluate the targeting properties of radiocobalt-labelled DOTA-Z(EGFR:2377). DOTA-Z(EGFR:2377) was labelled with Co-57 (T-1/2 = 271.8 d), Co-55 (T-1/2 = 17.5 h), and, for comparison, with the positron-emitting radionuclide Ga-68 (T-1/2 = 67.6 min) with preserved specificity of binding to EGFR-expressing A431 cells. The long-lived cobalt radioisotope Co-57 was used in animal studies. Both Co-57-DOTA-Z(EGFR:2377) and Ga-68-DOTA-Z(EGFR:2377) demonstrated EGFR-specific accumulation in A431 xenografts and EGFR-expressing tissues in mice. Tumour-to-organ ratios for the radiocobalt-labelled DOTA-Z(EGFR:2377) were significantly higher than for the gallium-labelled counterpart already at 3 h after injection. Importantly, Co-57-DOTA-Z(EGFR:2377) demonstrated a tumour-to-liver ratio of 3, which is 7-fold higher than the tumour-to-liver ratio for (68)GaDOTA-Z(EGFR:2377). The results of this study suggest that the positron-emitting cobalt isotope 55Co would be an optimal label for DOTA-Z(EGFR:2377) and further development should concentrate on this radionuclide as a label.

  • Sepulveda, Jorge I. Ramirez
    et al.
    Karolinska Univ Hosp, Karolinska Inst, Dept Med, Unit Expt Rheumatol, SE-17176 Stockholm, Sweden..
    Kvarnstrom, Marika
    Karolinska Univ Hosp, Karolinska Inst, Dept Med, Unit Expt Rheumatol, SE-17176 Stockholm, Sweden..
    Eriksson, Per
    Linkoping Univ, Div Rheumatol, Dept Clin Expt Med, Linkoping, Sweden..
    Mandl, Thomas
    Skane Univ Hosp, Dept Rheumatol, Malmo, Sweden..
    Norheim, Katrine Braekke
    Stavanger Univ Hosp, Dept Internal Med, Clin Immunol Unit, Stavanger, Norway..
    Johnsen, Svein Joar
    Stavanger Univ Hosp, Dept Internal Med, Clin Immunol Unit, Stavanger, Norway..
    Hammenfors, Daniel
    Univ Bergen, Dept Clin Sci, Broegelmann Res Lab, Bergen, Norway.;Haukeland Hosp, Dept Rheumatol, Bergen, Norway..
    Jonsson, Malin V.
    Univ Bergen, Dept Clin Sci, Broegelmann Res Lab, Bergen, Norway.;Univ Bergen, Sect Oral & Maxillofacial Radiol, Dept Clin Dent, Bergen, Norway..
    Skarstein, Kathrine
    Univ Bergen, Dept Clin Med, Gade Lab Pathol, Bergen, Norway.;Haukeland Hosp, Dept Pathol, Bergen, Norway..
    Brun, Johan G.
    Univ Bergen, Dept Clin Sci, Broegelmann Res Lab, Bergen, Norway.;Haukeland Hosp, Dept Rheumatol, Bergen, Norway..
    Rönnblom, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Rheumatology. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Forsblad-d'Elia, Helena
    Umea Univ, Dept Publ Hlth & Clin Med, Rheumatol, Umea, Sweden..
    Bucher, Sara Magnusson
    Orebro Univ, Fac Med & Hlth, Dept Rheumatol, Orebro, Sweden..
    Baecklund, Eva
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Rheumatology. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Theander, Elke
    Skane Univ Hosp, Dept Rheumatol, Malmo, Sweden..
    Omdal, Roald
    Stavanger Univ Hosp, Dept Internal Med, Clin Immunol Unit, Stavanger, Norway..
    Jonsson, Roland
    Univ Bergen, Dept Clin Sci, Broegelmann Res Lab, Bergen, Norway.;Haukeland Hosp, Dept Rheumatol, Bergen, Norway..
    Nordmark, Gunnel
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Rheumatology. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Wahren-Herlenius, Marie
    Karolinska Univ Hosp, Karolinska Inst, Dept Med, Unit Expt Rheumatol, SE-17176 Stockholm, Sweden..
    Long-term follow-up in primary Sjogren's syndrome reveals differences in clinical presentation between female and male patients2017In: Biology of Sex Differences, ISSN 2042-6410, Vol. 8, 25Article in journal (Refereed)
    Abstract [en]

    Background: Despite men being less prone to develop autoimmune diseases, male sex has been associated with a more severe disease course in several systemic autoimmune diseases. In the present study, we aimed to investigate differences in the clinical presentation of primary Sjogren's syndrome (pSS) between the sexes and establish whether male sex is associated with a more severe form of long-term pSS. Methods: Our study population included 967 patients with pSS (899 females and 68 males) from Scandinavian clinical centers. The mean follow-up time (years) was 8.8 +/- 7.6 for women and 8.5 +/- 6.2 for men (ns). Clinical data including serological and hematological parameters and glandular and extraglandular manifestations were compared between men and women. Results: Male patient serology was characterized by more frequent positivity for anti-Ro/SSA and anti-La/SSB (p = 0. 02), and ANA (p = 0.02). Further, men with pSS were more frequently diagnosed with interstitial lung disease (p = 0. 008), lymphadenopathy (p = 0.04) and lymphoma (p = 0.007). Conversely, concomitant hypothyroidism was more common among female patients (p = 0.009). Conclusions: We observe enhanced serological responses and higher frequencies of lymphoma-related extraglandular manifestations in men with pSS. Notably, lymphoma itself was also significantly more common in men. These observations may reflect an aggravated immune activation and a more severe pathophysiological state in male patients with pSS and indicate a personalized managing of the disease due to the influence of the sex of patients with pSS.

  • Pfister, Anna
    Sahlgrenska Academy at University of Gothenburg.
    Outcomes of Myosin 1C Gene Expression Depletion on Cancer-related Pathways, in Vitro and in Clinical Samples2016Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    The unconventional myosin IC has previously been suggested to be a haploinsufficient tumour suppressor. The mechanism for this action has hitherto been unknown, however, and hence we decided to attempt to elucidate the genes involved. The first study involved knock-down of MYO1C using siRNA technology followed by whole transcriptiome microarray analysis performed on samples taken at different time points post transfection. This revealed a cornucopia of differential expressions compared to the negative control, among them we found an early up-regulation of the PI3K/AKT pathway and the pathway for prostate cancer. Among the down regulated pathways we found endometrial-, colorectal cancer and small cell lung cancer as well as the cell cycle pathway which was a little counter intuitive to the hypothesis that MYO1C suppresses cancer. For the next study six different genes (CCND1, CCND2, CDKN2B, CDKN2C, MYC, RBL1) important for the transitions into S-phase of the cell cycle were therefore chosen for validation using qPCR. These six genes and MYO1C were analysed on both the original time series and a new biological replicate as well as a well stratified set of endometrial carcinoma samples. We were able to verify the significant down-regulation of CCND2 in both time series indicating that this is caused by the depletion of MYO1C. In the tumour samples we saw a negative correlation between the expression of MYO1C and FIGO grade corroborating results previously found by our group when looking at protein expression.

  • Imamura, Fumiaki
    et al.
    Sharp, Stephen J.
    Koulman, Albert
    Schulze, Matthias B.
    Kröger, Janine
    Griffin, Julian L.
    Huerta, José M.
    Guevara, Marcela
    Sluijs, Ivonne
    Agudo, Antonio
    Ardanaz, Eva
    Balkau, Beverley
    Boeing, Heiner
    Chajes, Veronique
    Dahm, Christina C.
    Dow, Courtney
    Fagherazzi, Guy
    Feskens, Edith J. M.
    Franks, Paul W.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Family Medicine. Department of Clinical Sciences, Lund University, Skåne University Hospital, Malmö, Sweden.
    Gavrila, Diana
    Gunter, Marc
    Kaaks, Rudolf
    Key, Timothy J.
    Khaw, Kay-Tee
    Kuehn, Tilman
    Melander, Olle
    Molina-Portillo, Elena
    Nilsson, Peter M.
    Olsen, Anja
    Overvad, Kim
    Palli, Domenico
    Panico, Salvatore
    Rolandsson, Olov
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Family Medicine.
    Sieri, Sabina
    Sacerdote, Carlotta
    Slimani, Nadia
    Spijkerman, Annemieke M. W.
    Tjønneland, Anne
    Tumino, Rosario
    van der Schouw, Yvonne T.
    Langenberg, Claudia
    Riboli, Elio
    Forouhi, Nita G.
    Wareham, Nick J.
    A combination of plasma phospholipid fatty acids and its association with incidence of type 2 diabetes: The EPIC-InterAct case-cohort study2017In: PLoS Medicine, ISSN 1549-1277, E-ISSN 1549-1676, Vol. 14, no 10, e1002409Article in journal (Refereed)
    Abstract [en]

    Background Combinations of multiple fatty acids may influence cardiometabolic risk more than single fatty acids. The association of a combination of fatty acids with incident type 2 diabetes (T2D) has not been evaluated.

    Methods and findings We measured plasma phospholipid fatty acids by gas chromatography in 27,296 adults, including 12,132 incident cases of T2D, over the follow-up period between baseline (1991-1998) and 31 December 2007 in 8 European countries in EPIC-InterAct, a nested casecohort study. The first principal component derived by principal component analysis of 27 individual fatty acids (mole percentage) was the main exposure (subsequently called the fatty acid pattern score [FA-pattern score]). The FA-pattern score was partly characterised by high concentrations of linoleic acid, stearic acid, odd-chain fatty acids, and very-long-chain saturated fatty acids and low concentrations of.-linolenic acid, palmitic acid, and long-chain monounsaturated fatty acids, and it explained 16.1% of the overall variability of the 27 fatty acids. Based on country-specific Prentice-weighted Cox regression and random-effects meta-analysis, the FA-pattern score was associated with lower incident T2D. Comparing the top to the bottom fifth of the score, the hazard ratio of incident T2D was 0.23 (95% CI 0.19-0.29) adjusted for potential confounders and 0.37 (95% CI 0.27-0.50) further adjusted for metabolic risk factors. The association changed little after adjustment for individual fatty acids or fatty acid subclasses. In cross-sectional analyses relating the FA-pattern score to metabolic, genetic, and dietary factors, the FA-pattern score was inversely associated with adiposity, triglycerides, liver enzymes, C-reactive protein, a genetic score representing insulin resistance, and dietary intakes of soft drinks and alcohol and was positively associated with high-density-lipoprotein cholesterol and intakes of polyunsaturated fat, dietary fibre, and coffee (p < 0.05 each). Limitations include potential measurement error in the fatty acids and other model covariates and possible residual confounding.

    Conclusions A combination of individual fatty acids, characterised by high concentrations of linoleic acid, odd-chain fatty acids, and very long-chain fatty acids, was associated with lower incidence of T2D. The specific fatty acid pattern may be influenced by metabolic, genetic, and dietary factors.

  • Rönnby, Johan
    et al.
    Södertörn University, School of Historical and Contemporary Studies, Archaeology. Södertörn University, School of Historical and Contemporary Studies, MARIS (Maritime Archaeological Research Institute).
    Sjöblom, Ingvar
    Södertörn University, School of Historical and Contemporary Studies, MARIS (Maritime Archaeological Research Institute).
    Havsguden från Västervik: om skeppet Neptunus och vasakungarnas nya stora kravlar2015In: Västerviks historia: förhistoria och arkeologi II / [ed] Palm, Veronica, Västervik: Västerviks Museum , 2015, 11-37 p.Chapter in book (Refereed)
  • Hylving, L
    RISE, Swedish ICT, Viktoria.
    Digitalization Dynamics: User Interface Innovation in an Automative Setting2015Doctoral thesis, monograph (Other academic)
  • Warensjö Lemming, Eva
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Orthopaedics.
    Byberg, Liisa
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Orthopaedics.
    Melhus, Håkan
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Clinical pharmacogenomics and osteoporosis.
    Wolk, Alicja
    Karolinska Inst, Inst Environm Med, Div Nutr Epidemiol.
    Michaëlsson, Karl
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Orthopaedics.
    Long-term a posteriori dietary patterns and risk of hip fractures in a cohort of women2017In: European Journal of Epidemiology, ISSN 0393-2990, E-ISSN 1573-7284, Vol. 32, no 7, 605-616 p.Article in journal (Refereed)
    Abstract [en]

    Dietary pattern analysis is a useful tool to study the importance of food components in the context of a diet and how they relate to health and disease. The association between dietary patterns and fractures is at present uncertain. We aimed to study associations between dietary patterns and risk of hip fracture in the Swedish Mammography Cohort, including 56,736 women (median baseline age 52 years). Diet data was collected in food frequency questionnaires at two investigations and dietary patterns were defined by principal component analysis using 31 food groups. Information on hip fractures was collected from the Swedish National Patient Register. Multivariable adjusted hazard ratios (HR) with 95% confidence intervals (CI) were estimated in Cox proportional hazards regression analysis. The two patterns identified-the healthy and Western/convenience dietary patterns-were time-updated and analysed. During a median follow-up time of 25.5 years, 4997 women experienced a hip fracture. Hip fracture rate was 31% lower in the highest compared to the lowest quartile of the healthy dietary pattern [HR (95% CI) 0.69 (0.64; 0.75)]. In contrast, women in the highest compared to the lowest quartile of the Western/convenience dietary pattern had a 50% higher [HR (95% CI) 1.50 (1.38; 1.62)] hip fracture rate. Further, in each stratum of a Western/convenience dietary pattern a higher adherence to a healthy dietary pattern was associated with less hip fractures. The present results suggest that a varied healthy diet may be beneficial for the prevention of fragility fractures in women.

  • Petersen, Julian
    et al.
    Karolinska Inst, Sect Receptor Biol & Signaling, Dept Physiol & Pharmacol, S-17177 Stockholm, Sweden..
    Wright, Shane C.
    Karolinska Inst, Sect Receptor Biol & Signaling, Dept Physiol & Pharmacol, S-17177 Stockholm, Sweden..
    Rodriguez, David
    Stockholm Univ, Dept Biochem & Biophys, Sci Life Lab, SE-10691 Stockholm, Sweden..
    Matricon, Pierre
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Cell and Molecular Biology, Computational Biology and Bioinformatics. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Lahav, Noa
    Hebrew Univ Jerusalem, Inst Chem, IL-91904 Jerusalem, Israel..
    Vromen, Aviv
    Hebrew Univ Jerusalem, Inst Chem, IL-91904 Jerusalem, Israel..
    Friedler, Assaf
    Hebrew Univ Jerusalem, Inst Chem, IL-91904 Jerusalem, Israel..
    Stromqvist, Johan
    Single Technol AB, SE-11428 Stockholm, Sweden..
    Wennmalm, Stefan
    Royal Inst Technol, Dept Appl Phys, Expt Biomol Phys Grp, Sci Life Lab, SE-17165 Solna, Sweden..
    Carlsson, Jens
    Uppsala University, Science for Life Laboratory, SciLifeLab. Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Cell and Molecular Biology, Computational Biology and Bioinformatics.
    Schulte, Gunnar
    Karolinska Inst, Sect Receptor Biol & Signaling, Dept Physiol & Pharmacol, S-17177 Stockholm, Sweden.;Masaryk Univ, Dept Expt Biol, Fac Sci, Kotlarska 2, CS-61137 Brno, Czech Republic..
    Agonist-induced dimer dissociation as a macromolecular step in G protein-coupled receptor signaling2017In: Nature Communications, ISSN 2041-1723, E-ISSN 2041-1723, Vol. 8, 226Article in journal (Refereed)
    Abstract [en]

    G protein-coupled receptors (GPCRs) constitute the largest family of cell surface receptors. They can exist and act as dimers, but the requirement of dimers for agonist-induced signal initiation and structural dynamics remains largely unknown. Frizzled 6 (FZD6) is a member of Class F GPCRs, which bind WNT proteins to initiate signaling. Here, we show that FZD6 dimerizes and that the dimer interface of FZD6 is formed by the transmembrane a-helices four and five. Most importantly, we present the agonist-induced dissociation/re-association of a GPCR dimer through the use of live cell imaging techniques. Further analysis of a dimerization-impaired FZD6 mutant indicates that dimer dissociation is an integral part of FZD6 signaling to extracellular signal-regulated kinases1/2. The discovery of agonistdependent dynamics of dimers as an intrinsic process of receptor activation extends our understanding of Class F and other dimerizing GPCRs, offering novel targets for dimerinterfering small molecules.

  • Gerasimova, Julia V.
    et al.
    Russian Acad Sci, Komarov Bot Inst, Prof Popova St 2, St Petersburg 197376, Russia..
    Ekman, Stefan
    Uppsala University, Music and Museums, Museum of Evolution.
    Taxonomy and nomenclature of seven names in Bacidia (Ramalinaceae, Lecanorales) described from Russia2017In: Phytotaxa, ISSN 1179-3155, E-ISSN 1179-3163, Vol. 316, no 3, 292-296 p.Article in journal (Refereed)
    Abstract [en]

    We aim to increase understanding and improve taxonomy of seven names currently treated in Bacidia that were described from Russian territory based on material collected during 19th-century expeditions: Bacidia alborussula, B. freshfieldii, B. graminum, B. indigens, B. primigenia, B. subabbrevians, and B. xylophila. B. alborussula, B. graminum, and B. indigens are transferred here to Haematomma, Lecania, and Bacidina, respectively. Bacidia freshfieldii and B. subabbrevians belong in the Ramalinaceae and are provisionally kept in Bacidia even though none of them is congeneric with the type of that genus. B. primigenia belongs in Arthrorhaphis, but we refrain from making any new combination owing to its questionable status as a species distinct from A. grisea. B. xylophila is a younger synonym of Lecania subfuscula. We designate lectotypes for names previously not typified and for which syntypes exist: Lecidea alborussula, L. graminum, L. indigens, and L. subabbrevians.

  • Public defence: 2017-12-12 10:00 F3, Stockholm
    Bogodorova, Tetiana
    KTH, School of Electrical Engineering (EES), Electric Power and Energy Systems.
    Modeling, Model Validation and Uncertainty Identification for Power System Analysis2017Doctoral thesis, monograph (Other academic)
    Abstract [en]

    It is widely accepted that correct system modeling and identification are among the most important issues power system operators face when managing instability and post-contingency scenarios. The latter is usually performed involving special computational tools that allow the operator to forecast, prevent system failure and take appropriate actions according to protocols for different contingency cases in the system. To ensure that operators make the correct simulation-based decisions, the power system models have to be validated continuously. This thesis investigates power system modeling, identification and validation problems that are formulated and based on data provided by operators, and offers new methods and deeper insight into stages of an identification cycle considering the specifics of power systems.

    One of the problems this thesis tackled is the selection of a modeling and simulation environment that provides transparency and possibility for unambiguous model exchange between system operators. Modelica as equation-based language fulfills these requirements. In this thesis Modelica phasor time domain models were developed and software-to-software validated against conventional simulation environments, i.e. SPS/Simulink and PSAT in MATLAB.

    Parameter estimation tasks for Modelica models require a modular and extensible toolbox. Thus, RaPiD Toolbox, a framework that provides system identification algorithms for Modelica models, was developed in MATLAB. Contributions of this thesis are an implementation of the Particle Filter algorithm and validation metrics for parameter identification. The performance of the proposed algorithm has been compared with Particle Swarm Optimization (PSO) algorithm when combined with simplex search and parallelized to get computational speed up. The Particle Filter outperformed PSO when estimating turbine-governor model parameters in the Greek power plant model relying on real measurements.

    This thesis also analyses different model structures (Nonlinear AutoRegressive eXogenous (NARX) model, Hammerstein-Wiener model, and high order transfer function) that are selected to reproduce nonlinear dynamics of a Static VAR Compensator (SVC) under incomplete information available for National Grid system operator. The study has shown that standard SVC model poorly reproduces the measured dynamics of the real system. Therefore, black-box mathematical modeling and identification approach has been proposed to solve the problem. Also, the introduced combination of first-principle and black-box approach has shown the best output fit. The methodology following identification cycle together with model order selection and model validation issues was presented in detail.

    Finally, one of the major contributions is a new method to formulate the uncertainty of parameters estimated in the form of a multimodal Gaussian mixture distribution that is estimated from the Particle Filter output by applying statistical methods to select the standard deviations. The proposed methodology gives additional insight into power system properties when estimating the parameters of the model. This allows power system analysts to decide on the design of validation tests for the chosen model.

  • Gustavsson, Martin
    et al.
    Stockholms centrum för forskning om offentlig sektor (Score), Stockholms universitet och Handelshögskolan i Stockholm.
    Melldahl, Andreas
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Educational Sciences, Department of Education.
    Länsteatrarnas ekonomiska handlingsutrymme: Intäkter, utgifter och personal 1980–20152017Report (Other academic)
    Abstract [sv]

    Rapporten redovisar hur länsteatrarnas inkomster, utgifter och personalstyrka har förändrats mellan 1980 och 2015, en period som präglats av tre olika kulturpolitiska reformer (sjösatta 1974, 1996 och 2009).

    I ett bakgrundsavsnitt diskuteras bristen på bra kulturstatistik. Obrutna serier med statistik som sträcker sig över olika kulturpolitiska perioder har saknats. För att kunna jämföra länsteatrarnas ekonomiska förhållanden under perioder märkta av olika kulturpolitiska ideal har statistik därför samlats in från olika arkiv och skarvats ihop för hela den nämnda 35-årsperioden.

    Rapportens första undersökande del visar att det har skett en resursmässig förstärkning av länsteatrarna över tid (mätt med konsumentprisindex). Utvecklingen har dock varit ojämn. Den följer bredare trender i samhällsekonomin. Den genomsnittliga länsteaterns intäkter ökade markant mellan 1980 och 1990 (1974 års kulturpolitiska epok), minskade påtagligt mellan 1990 och 1996 (90-talets ekonomiska kris), ökade kraftigt mellan 1996 och 2005 (1996 års kulturpolitiska era), minskade noterbart mellan 2005 och 2012 (det sena 00-talets ekonomiska kris) och ökade något mellan 2012 och 2015 (2009 års kulturpolitiska period). Vi visade också att de genomsnittliga utgifternas utveckling följer samma typ av cykliska förlopp som de genomsnittliga intäkternas.

    Rapportens andra del studerade finansieringens effekter på kärnverksamheten, exemplifierad av personalstyrkans storlek och sammansättning. Länsteatrarnas största utgiftspost utgörs av personalkostnader. För att undersöka om lönekostnadsutvecklingen undergrävt uppräkningen av de offentliga anslagen justerades beloppen med olika löneindex. Nu blev ett motsatt utvecklingsscenario synligt. Istället för den trendmässiga – förvisso försiktiga och periodvisa – ökningen av intäkterna som visades när anslagen räknades om med konsumentprisindex minskade anslagen över tid när de justerades med löneindex. Den genomsnittliga länsteatern kan inte i dag, trots den måttliga resursförstärkningen de senaste åren, köpa lika mycket personal som i början av undersökningsperioden.I en separat delstudie visade vi även att antalet arbetade timmar av anställd ”konstnärlig” personal på teatrarna minskade över tid, medan antalet årsverken för ”administrativ” personal ökade något.

    I en avslutande delstudie ställdes följdfrågor om personalsituationen. Vi visade på den något paradoxala situationen att länsteatrarna – trots lägre köpkraft (mätt med löneindex) och färre ersatta arbetstimmar utförda av anställd konstnärlig personal (årsverken) – lyckats enrollera fler personer. En delförklaring till denna utveckling ligger i att länsteatrarna under de senaste tio åren alltmer börjat befolkas av visstidsoch korttidsanställd personal (med A-skattsedel) och frivilliga eller ofrivilliga företagare (med F- och FA-skattsedel).