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  • Sundström, Christofer
    et al.
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Frisk, Erik
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Nielsen, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    A Platform for Overall Monitoring and Diagnosis for Hybrid Vehicles2010Report (Other academic)
    Abstract [en]

    Compared with conventional vehicles, designing hybrid electric vehicles includes new features, such as energy management and monitoring of the electrical components. To be able to investigate such issues a simulation platform of a hybrid vehicle, driver, and diagnosis system is developed based on the CAPSim model library. The simulation platform is component based, and is able to handle different powertrain configurations. In this investigation a parallel hybrid is modeled and parameterized to represent a long haulage truck. To be able to easily change a model of a component in the vehicle model, every model of a specific component use the same sets of input and output signals. The vehicle model is based on dynamic equations and in general simple models of the components, since the interplay of the components is of major interest in this investigation. Three model based diagnosis systems are developed and implemented in the platform with a twofolded purpose. The first purpose is to demonstrate the feasibility of the platform. The second purpose is to investigate issues when designing diagnosis systems on vehicle level of a hybrid vehicle powertrain. New features, for example mode switches in the system and a freedom in choosing operating points of the components via the energy management, affect the diagnosis system. The influence of these issues on the performance of the diagnosis system is investigated by design and implementation of three diagnosis systems on a vehicle level. The diagnosis systems are based on three sensor configurations. Two of these consist of several sensors and one system uses few sensors. In one of the systems using information from several sensors, the sensors are placed close to the components that are to be monitored, while the sensors in the other system is based on a different sensor configuration. All three diagnosis systems detect specific faults, here specifically faults in the electrical components in a hybrid vehicle powertrain, but the methodology is generic. It is shown that there is a connection between the design of the energy management and the three diagnosis systems, and that this interplay is of special relevance when models of components are valid only in some operating modes. The diagnosis system based on few sensors is more complex and includes a larger part of the vehicle model than the system based on several sensors placed close to the components to be monitored.

  • Public defence: 2017-09-22 09:00 KBE303-Stora hörsalen, KBC-huset
    Zhou, Yang
    Umeå University, Faculty of Science and Technology, Department of Molecular Biology (Faculty of Science and Technology).
    Regulation of pre-mRNA splicing and mRNA degradation in Saccharomyces cerevisiae2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Messenger RNAs are transcribed and co-transcriptionally processed in the nucleus, and transported to the cytoplasm. In the cytoplasm, mRNAs serve as the template for protein synthesis and are eventually degraded. The removal of intron sequences from a precursor mRNA is termed splicing and is carried out by the dynamic spliceosome. In this thesis, I describe the regulated splicing of two transcripts in Saccharomyces cerevisiae. I also describe a study where the mechanisms that control the expression of magnesium transporters are elucidated.

    The pre-mRNA retention and splicing (RES) complex is a spliceosome-associated protein complex that promotes the splicing and nuclear retention of a subset of pre-mRNAs. The RES complex consists of three subunits, Bud13p, Snu17p and Pml1p. We show that the lack of RES factors causes a decrease in the formation of N4-acetylcytidine (ac4C) in tRNAs. This phenotype is caused by inefficient splicing of the pre-mRNA of the TAN1 gene, which is required for the formation of ac4C in tRNAs. The RES mutants also show growth defects that are exacerbated at elevated temperatures. We show that the temperature sensitive phenotype of the bud13Δ and snu17Δ cells is caused by the inefficient splicing of the MED20 pre-mRNA. The MED20 gene encodes a subunit of the Mediator complex. Unspliced pre-mRNAs that enter the cytoplasm are usually degraded by the nonsense-mediated mRNA decay (NMD) pathway, which targets transcripts that contain premature translation termination codons. Consistent with the nuclear retention function of the RES complex, we find that NMD inactivation in the RES mutants leads to the accumulation of both TAN1 and MED20 pre-mRNAs. We also show that the cis-acting elements that promote RES-dependent splicing are different between the TAN1 and MED20 pre-mRNAs.

    The NMD pathway also targets transcripts with upstream ORFs (uORFs) for degradation. The ALR1 gene encodes the major magnesium importer in yeast, and its expression is controlled by the NMD pathway via a uORF in the 5’ untranslated region. We show that the ribosome reaches the downstream main ORF by a translation reinitiation mechanism. The NMD pathway was shown to control cellular Mg2+ levels by regulating the expression of the ALR1 gene. We further show that the NMD pathway targets the transcripts of the vacuolar Mg2+ exporter Mnr2p and the mitochondrial Mg2+ exporter Mme1p for degradation.

    In summary, we conclude that the RES complex has a role in the splicing regulation of a subset of transcripts. We also suggest a regulatory role for the NMD pathway in maintaining the cellular Mg2+ concentration by controlling the expression of Mg2+ transporters.

  • Frisk, Erik
    et al.
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Åslund, Jan
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Lowering Orders of Derivatives in Non-linear Consistency Relations - Theory and Simulation Examples2003Report (Other academic)
    Abstract [en]

    Consistency relations are often used to design residual generators based on non-linear process models. A main difficulty is that they generally include time differentiated versions of known or measured signals which are difficult to estimate in a noisy environment, especially higher order derivatives. The main results of this paper show how to lower, or if possible avoid, the need to estimate derivatives of known signals in order to compute the residual. This is achieved by rewriting the problem into an integrability problem using state-space realization theory. An attractive feature of the approach is that general differential algebraic system descriptions can be handled in the same way as for example ordinary differential equations and also that stability of the residual generator is always guaranteed.

  • Eriksson, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Documentation for the Chemical Equilibrium Program Package CHEPP2000Report (Other academic)
    Abstract [en]

    A program package has been developed that calculates chemical equilibrium and thermodynamic properties of reactants and products of a combustion reaction between fuel and air. The package consists of the following four parts: 1) A program for calculating chemical equilibrium. 2) A database that contains thermochemical information about the molecules, which comes from the GRI-Mech tables. 3) A GUI that allows the user to easily select fuels, fuel/air ratio for the reaction, and combustion products. 4) A set of functions designed to access the thermochemical database and the chemical equilibrium programs. The program package is validated with respect to how well it can reproduce results shown in the standard literature. The thermodynamic properties for the individual molecules and the results from the equilibrium calculation all agree with the results shown in the literature. There is almost perfect agreement, between the results produced by the program package and those shown in the book by Heywood, when comparing the thermodynamic properties of the mixture of equilibrium products.

  • Eriksson, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Increasing the Efficiency of SI-Engines by Spark Advance Control and Water Injection1997Report (Other academic)
    Abstract [en]

    By directly measuring in-cylinder parameters and adjusting the spark advance, the engine efficiency can be maximized. A feedback scheme for spark-advance control using the ionization current as sensed variable has earlier been presented. One issue is to verify that the algorithm works when the environmental conditions changes the burn rate. Humidity significantly affects the burn rate and active water injection is used to slow down the combustion giving a peak pressure position (PPP) that occurs too late. The ionization current based feedback-scheme adjusts the spark advance, and moves the PPP back to optimum. An additional result is that the engine efficiency can be increased by combining active supply of water to the combustion and the spark-advance control scheme.

  • Wahlström, Johan
    et al.
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Eriksson, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Modeling of a Diesel Engine with Intake Throttle, VGT, and EGR2010Report (Other academic)
    Abstract [en]

    A mean value model of a diesel engine with intake throttle, VGT, and EGR is developed, parameterized, and validated. The intended model applications are system analysis, simulation, and development of model-based control systems. The goal is to construct a model that describes the gas flow dynamics includ- ing the dynamics in the intercooler pressure, manifold pressures, turbocharger, EGR, and actuators with few states in order to have short simulation times. An investigation of model complexity and descriptive capabilities is performed, resulting in a model that has only eleven states. To tune and validate the model, stationary and dynamic measurements have been performed in an engine labo- ratory at Scania CV AB. All the model parameters are estimated automatically using weighted least squares optimization of both the sub-models and the com- plete model. Dynamic measurements and simulations show that the proposed model cap- tures the essential system properties, i.e. non-minimum phase behaviors, over- shoots, and sign reversals. Validations of the entire model show that the mean value of all absolute relative errors for all measured outputs are equal to 7.4%. A system analysis of the proposed model is performed in order to obtain insight into a VGT and EGR control problem where the goal is to control the performance variables oxygen fuel ratio lambdaO and EGR-fraction xegr. Step responses over the entire operating region show that the channels VGT to lambdaO, EGR to lambdaO, and VGT to xegr have sign reversals.

  • Frisk, Erik
    et al.
    Linköping University, Department of Electrical Engineering, Vehicular Systems.
    Nyberg, Mattias
    Linköping University, Department of Electrical Engineering, Vehicular Systems.
    Using Minimal Polynomial Bases for Model-Based Fault Diagnosis: A Demonstration Document for PolyX, Ltd1999Report (Other academic)
    Abstract [en]

    This document is a demonstration document, demonstrating the use of the Polynomial Toolbox for Matlab when designing residual generators for fault diagnosis. A brief introduction to the residual generation problem for fault diagnosis in linear systems is given and a solution based on polynomial methods are outlined. Also, a design example, complete with \sc Matlab code illustrates how the Polynomial Toolbox can be used in the design of residual generators.

  • Frisk, Erik
    et al.
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, The Institute of Technology.
    Nyberg, Mattias
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, The Institute of Technology.
    Residual Generation for Fault Diagnosis of Systems Described by General Linear Differential-Algebraic Equations (revised)2005Report (Other academic)
    Abstract [en]

    Linear residual generation for DAE systems has been considered. In all results derived, no distinction between input and output signals is done. A complete characterization and parameterization of all residual generators is presented. Further, a condition for fault detectability in DAE systems is given. Based on the characterization of all residual generators, a design strategy for residual generators for DAE systems is presented. Given that a set of faults are detectable, the design strategy will result in a residual generator sensitive to all the detectable faults. Further the residual generator is guaranteed to be of lowest possible order. Special care has been devoted to assure this property also for non-controllable systems.

  • Frisk, Erik
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, The Institute of Technology.
    Efficient Elimination Orders for the Elimination Problem in Diagnosis2003Report (Other academic)
    Abstract [en]

    A consistency relation is a constraint on the time evolution of known variables (and their time derivatives) that is fulfilled if the known variables are consistent with a model. Such relations are useful in diagnosis and can be derived using elimination theory. Unfortunately, even apparently small elimination problems proves impossible to compute on standard computers. An approach to lessen the computational burden is to divide the complete elimination problem into a set of smaller elimination problems. This is done by analysing the structure of the model equations using graph theoretical algorithms from the field of sparse factorization of symmetric matrices. The algorithms are implemented in Mathematica and exemplified on a fluid-flow system where the original elimination problem does not terminate. Applying the proposed algorithms give an elimination strategy that terminates with a solution in just a few seconds.

  • Brugård, Jan
    et al.
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, The Institute of Technology.
    Eriksson, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, The Institute of Technology.
    Nielsen, Lars
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, The Institute of Technology.
    Mean Value Engine Modeling of a Turbo Charged Spark Ignited Engine - A Principle Study2001Report (Other academic)
    Abstract [en]

    Object oriented modeling of physical systems is an interesting paradigm, which has the potential to offer reusable models and model components. The aim of this study i to investigate how to build mean value models for automotive engines. MathModelica, a modeling tool for the object oriented modeling language Modelica, is used in this study. Several sub models have been developed for the different parts of the engine. Th models cover the air filter, intercooler, throttle, base engien, exhaust system, compressor, turbine, turbine shaft, and volumes. It is shown how the components can be connected to form both turbo charged engines as well as a naturally aspirated engines, which shows that the paradigm is applicable for the modeling and confirms the modeling principle. One problem that has popped up att several occasions is the selection of initial conditions for the simulation. Especially when restrictions with low pressure drops are connected between two volumes, the simulation engine has problems finding initial conditions. The models have been compared to measured engine data collected at a test bench in Vehicular Systems laboratory at Linköping University. The agreement with measurement data is good and the models work as expected.

  • Nyberg, Mattias
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, The Institute of Technology.
    Design of a Complete FDI System based on a Performance Index With Application to an Automotive Engine1997Report (Other academic)
    Abstract [en]

    Assuming residual generators are already available, there are still several choices to be made when a complete FDI system is to be designed. This is a time-consuming engineering work so for this purpose, a systematic procedure is proposed. The procedure is phrased as an optimization problem. The goal is to minimize a new probability based performance index, which is derived from measurements on the real process. To increase the robustness of the FDI system, a don’t care option is introduced in the residual structure. The procedure is successfully applied to the problem of FDI design for the air intake system of an SI-engine.

  • Nyberg, Mattias
    Linköping University, Department of Electrical Engineering, Vehicular Systems.
    The Polybox Example using the Framework of Structured Hypothesis Tests2001Report (Other academic)
    Abstract [en]

    The POLYBOX example is a standard example within the AI-field of model-based diagnosis research. Here, this example is discussed in the perspective of structured hypothesis tests (SHT). Even though the SHT framework was primarily developed for handling systems with noise, it has here been shown that it can perform very well in also noise-free systems. In the POLYBOX example, it manage to always give a complete and logically sound diagnosis statement, i.e. a complete and correct list of the possible fault modes. On the contrary, the established FDI framework (i.e. structured residuals) only manage to give a subset of the possible fault modes.

  • Krysander, Mattias
    et al.
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, The Institute of Technology.
    Nyberg, Mattias
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, The Institute of Technology.
    Structural Analysis for Fault Diagnosis of DAE Systems Utilizing Graph Theory and MSS Sets2002Report (Other academic)
    Abstract [en]

    When designing model-based fault-diagnostic systems, the use of consistency relations (also called e.g. parity relations) is a common choice. Different consistency relations are sensitive to different subsets of faults, and thereby isolation can be achieved. This report presents an algorithm for finding a small set of submodels that can be used to derive consistency relations with highest possible diagnosis capability. The algorithm handles differential-algebraic models and is based on graph theoretical reasoning about the structure of the model. An important step towards finding these submodels, and therefore also towards finding consistency relations, is to find all minimal structurally singular (MSS) sets of equations. These sets characterize the fault diagnosability. The algorithm is applied to a large nonlinear industrial example, a part of a paper plant. In spite of the complexity of this process, a small set of consistency relations with high diagnosis capability is successfully derived.

  • Krysander, Mattias
    et al.
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Frisk, Erik
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Some theoretical results on sensor placement for diagnosis based on fault isolability specifications2007Report (Other academic)
    Abstract [en]

    This report presents the theoretical results of the work in. The report is not self-contained and should be considered to be complementary to the paper.

  • Nilsson, Tomas
    et al.
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Sundström, Christofer
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Nyberg, Peter
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Frisk, Erik
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Krysander, Mattias
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
    Offline driving pattern detection and identification under usage disturbances2012Report (Other academic)
    Abstract [en]

    Optimizing the configuration of a wheel loader to customer needs can lead to a significant increase in efficiency with respect to fuel economy, cost, component dimensioning etc. Experience show that even modest customer adaptation can save around 20% of fuel cost. A key motivator for this work is that wheel loader manufacturers in general does not have full information about customer usage of the machine and the main objective here is to develop an algorithm that automatically, using only production sensors, extracts information about the usage of a machine at a specific customer site. Two main challenges are that sensors are not located with respect to this task and the significant usage disturbances that typically occur during operation. The proposed solution is a robust method, based on a mix of techniques using basic signal processing, state automaton techniques, and parameter estimation algorithms. A key property of the method is the method of combining, individually very simple, basic techniques in a scheme where robustness are introduced. The approach is evaluated on measured data of a wheel loader loading gravel and shot rock.

  • Nyberg, Mattias
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, The Institute of Technology.
    Parity Functions as Universal Residual Generators and Tool for Fault Detectability Analysis1997Report (Other academic)
    Abstract [en]

    An important issue in diagnosis research is design methods for residual generation. One method is the Chow-Willsky scheme. Here an extension to the Chow-Willsky scheme, called the ULPE scheme is presented. It is shown that previous extensions to the Chow-Willsky scheme can not generate all possible parity equations for some linear systems. This is the case when there are dynamics controllable from fault but not from the inputs or disturbances. The ULPE scheme is able to handle also this case since it is, for both discrete and continuous linear systems, shown to be a universal design method for perfectly decoupling residual generators. Also included are two new straightforward conditions on the process for fault detectability and strong fault detectability respectively. A general condition for strong fault detectability has not been presented elsewhere. It is shown that fault detectability and strong fault detectability can be seen as system properties rather than properties of the residual generator.

  • Nyberg, Mattias
    et al.
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, The Institute of Technology.
    Frisk, Erik
    Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, The Institute of Technology.
    A Derivation of the Minimal Polynomial Basis Approach to Linear Residual Generation2001Report (Other academic)
    Abstract [en]

    A fundamental part of a fault diagnosis system is the residual generator. Here a new method, the minimal polynomial basis approach, for design of residual generators for linear systems, is presented. The residual generation problem is transformed into a problem of finding polynomial bases for null-spaces of polynomial matrices. This is a standard problem in established linear systems theory, which means that numerically efficient computational tools are generally available. It is shown that the minimal polynomial basis approach can find all possible residual generators and explicitly those of minimal order.

  • Raine, Amanda
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Molecular Medicine. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Manlig, Erika
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Molecular Medicine. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Wahlberg, Per
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Molecular Medicine. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Syvänen, Ann-Christine
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Molecular Medicine. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Nordlund, Jessica
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Molecular Medicine. Uppsala University, Science for Life Laboratory, SciLifeLab.
    SPlinted Ligation Adapter Tagging (SPLAT), a novel library preparation method for whole genome bisulphite sequencing2017In: Nucleic Acids Research, ISSN 0305-1048, E-ISSN 1362-4962, Vol. 45, no 6, e36Article in journal (Refereed)
    Abstract [en]

    Sodium bisulphite treatment of DNA combined with next generation sequencing (NGS) is a powerful combination for the interrogation of genome-wide DNA methylation profiles. Library preparation for whole genome bisulphite sequencing (WGBS) is challenging due to side effects of the bisulphite treatment, which leads to extensive DNA damage. Recently, a new generation of methods for bisulphite sequencing library preparation have been devised. They are based on initial bisulphite treatment of the DNA, followed by adaptor tagging of single stranded DNA fragments, and enable WGBS using low quantities of input DNA. In this study, we present a novel approach for quick and cost effectiveWGBS library preparation that is based on splinted adaptor tagging (SPLAT) of bisulphite-converted single-stranded DNA. Moreover, we validate SPLAT against three commercially available WGBS library preparation techniques, two of which are based on bisulphite treatment prior to adaptor tagging and one is a conventional WGBS method.

  • Pasea, Laura
    et al.
    UCL, Farr Inst Hlth Informat Res, London, England..
    Chung, Sheng-Chia
    UCL, Farr Inst Hlth Informat Res, London, England..
    Pujades-Rodriguez, Mar
    UCL, Farr Inst Hlth Informat Res, London, England.;Univ Leeds, MRC Med Bioinformat Ctr, Leeds Inst Biomed & Clin Sci, Leeds LS2 9JT, W Yorkshire, England..
    Moayyeri, Alireza
    UCL, Farr Inst Hlth Informat Res, London, England..
    Denaxas, Spiros
    UCL, Farr Inst Hlth Informat Res, London, England..
    Fox, Keith A. A.
    Univ Edinburgh, Ctr Cardiovasc Sci, Edinburgh, Midlothian, Scotland.;Royal Infirm Edinburgh NHS Trust, Edinburgh, Midlothian, Scotland..
    Wallentin, Lars
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Medicinska och farmaceutiska vetenskapsområdet, centrumbildningar mm, UCR-Uppsala Clinical Research Center. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Cardiology.
    Pocock, Stuart J.
    London Sch Hyg & Trop Med, Dept Med Stat, London, England..
    Timmis, Adam
    Barts & London Natl Inst Hlth Res Cardiovasc Biom, Barts Heart Ctr, London, England..
    Banerjee, Amitava
    UCL, Farr Inst Hlth Informat Res, London, England..
    Patel, Riyaz
    UCL, Farr Inst Hlth Informat Res, London, England..
    Hemingway, Harry
    UCL, Farr Inst Hlth Informat Res, London, England..
    Personalising the decision for prolonged dual antiplatelet therapy: development, validation and potential impact of prognosticmodels for cardiovascular events and bleeding in myocardial infarction survivors2017In: European Heart Journal, ISSN 0195-668X, E-ISSN 1522-9645, Vol. 38, no 14, 1048-1055A p.Article in journal (Refereed)
    Abstract [en]

    Aims The aim of this study is to develop models to aid the decision to prolong dual antiplatelet therapy (DAPT) that requires balancing an individual patient's potential benefits and harms Methods and results Using population-based electronic health records (EHRs) (CALIBER, England, 2000-10), of patients evaluated 1 year after acute myocardial infarction (MI), we developed (n= 12 694 patients) and validated (n= 5613) prognostic models for cardiovascular (cardiovascular death, MI or stroke) events and three different bleeding endpoints. We applied trial effect estimates to determine potential benefits and harms of DAPT and the net clinical benefit of individuals. Prognostic models for cardiovascular events (c-index: 0.75 (95% CI: 0.74, 0.77)) and bleeding (c index 0.72 (95% CI: 0.67, 0.77)) were well calibrated: 3-year risk of cardiovascular events was 16.5% overall (5.2% in the lowest-and 46.7% in the highest-risk individuals), while for major bleeding, it was 1.7% (0.3% in the lowest-and 5.4% in the highest-risk patients). For every 10 000 patients treated per year, we estimated 249 (95% CI: 228, 269) cardiovascular events prevented and 134 (95% CI: 87, 181) major bleeding events caused in the highest-risk patients, and 28 (95% CI: 19, 37) cardiovascular events prevented and 9 (95% CI: 0, 20) major bleeding events caused in the lowest-risk patients. There was a net clinical benefit of prolonged DAPT in 63-99% patients depending on how benefits and harms were weighted Conclusion Prognostic models for cardiovascular events and bleeding using population-based EHRs may help to personalise decisions for prolonged DAPT 1-year following acute MI.

  • Löfgren, Fredrik
    Linköping University, Department of Computer and Information Science, Artificial Intelligence and Integrated Computer Systems. Linköping University, Faculty of Science & Engineering.
    How may robots affect the labour market in the near future?2016In: Machines, jobs and equality: Technological changes and labour markets in Europe / [ed] Andreas Bergström and Karl Wennberg, The European Liberal Forum (ELF) , 2016, 105-134 p.Chapter in book (Other academic)
    Abstract [en]

    This chapter discusses how different applications for robots will affect the labour market in the near future. Near future refers to the next 10-50 years. It is likely that several occupations will disappear, but new ones will also emerge. However, we claim that the net result will be negative, which means that we will have higher unemployment. These effects will not happen overnight, and not all occupations will be affected. But, this will happen for a sufficient amount of the population for it to become a problem for society.

    The observations made in this chapter are not from the point of view of a social scientist, but that of a roboticist. The observations are taken together with readings of scientific literature on automation. I do not claim to have answers to the economic and social scientific problems thrown up, but to raise a set of critical questions for the reader.

    All the examples in this chapter are real technologies that exist, not just in science-fiction or future technology. However, most of the examples are still in their research stage and are either not available for the general public, or still very expensive.

    No one can predict the future in detail, but this chapter tries to provide a scenario of the future of different kinds of occupations through the perspective of the field of robotics. I have been developing robots for 15 years and will use some examples that I have constructed, but also examples from other roboticists. The chapter does not discuss the risks of automation for all occupations, but instead focuses on blue-collar workers, such as machine operators, the transportation sector with the advent of driverless cars, white-collar workers in offices, skilled professions in the legal and medical spheres, and creative workers.

  • Koch, Daniel
    KTH, School of Architecture and the Built Environment (ABE), Architecture.
    On Aesthetics and Spatial Configuration2017In: Proceedings: 11th International Space Syntax Symposium / [ed] Teresa Heitor, Miguel Serra, João Pinelo Silva, Maria Bacharel, Luisa Cannas da Silva, INSTITUTO SUPERIOR TÉCNICO , 2017, 162.1-162.14 p.Conference paper (Refereed)
    Abstract [en]

    This article takes as its point of departure that any question concerning architecture, in a broad sense, has cultural and aesthetic implications, whether directly concerned with them or focused on social, technical, functional or other concerns. From such an outset, so does spatial configuration. However, while questions of aesthetics have been addressed within syntax research, it has rarely been the central point. This article intends to address more specifically the question of spatial configuration as aesthetics, on the one hand, and the aesthetic implications of configurational analysis on the other. In doing so, it will discuss aesthetic implications of ostensibly non-aesthetic considerations by addressing aesthetics as cultural, social and formal values embedded in and expressed through architectural works, and mediated through engaged and distracted experience. Concretely, the discussion will revolve around a small selection of works to develop a reasoning around aesthetics and con guration. This includes Alexander Klein’s graphic methods to evaluate building plans and its relation to a selection of Mies van der Rohe’s works, to conclude with a discussion relating the ndings to habits and dispositions

  • Fashandi, Hossein
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Lai, Chung-Chuan
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Dahlqvist, Martin
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Lu, Jun
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Rosen, Johanna
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Hultman, Lars
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Greczynski, Grzegorz
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Andersson, Mike
    Linköping University, Department of Physics, Chemistry and Biology, Applied Sensor Science. Linköping University, Faculty of Science & Engineering.
    Lloyd Spetz, Anita
    Linköping University, Department of Physics, Chemistry and Biology, Applied Sensor Science. Linköping University, Faculty of Science & Engineering.
    Eklund, Per
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering.
    Ti2Au2C and Ti3Au2C2 formed by solid state reaction of gold with Ti2AlC and Ti3AlC22017In: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548XArticle in journal (Refereed)
    Abstract [en]

    Incorporation of layers of noble metals in non-van der Waals layered materials may be used to form novel layered compounds. Recently, we demonstrated a high-temperature-induced exchange process of Au with Si in the layered phase Ti3SiC2, resulting in the formation of Ti3AuC2 and Ti3Au2C2. Here, we generalize this technique showing that Au/Ti2AlC and Au/Ti3AlC2 undergo an exchange reaction at 650 [degree]C to form Ti2Au2C and Ti3Au2C2 and determine their structures by electron microscopy, X-ray diffraction, and ab initio calculations. These results imply that noble-metal-containing layered phases should be possible to synthesize in many systems. The metal to be introduced should be inert to the transition-metal carbide layers, and exhibit negative heat of mixing with the initial A element in a liquid phase or two-phase liquid/solid region at the annealing temperature.

  • Legeby, Ann
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Architecture, Urban Design.
    Koch, Daniel
    KTH, School of Architecture and the Built Environment (ABE), Architecture.
    Abshirini, Ehsan
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geoinformatics.
    CHARACTERIZING URBAN CENTRES: Reading configuration as point, line, field2017In: Proceedings of the 11th Space Syntax Symposium / [ed] Teresa Heitor, Miguel Serra, João Pinelo Silva, Maria Bacharel, Luisa Cannas da Silva, Instituto Superior Técnico , 2017, 78.1-78.16 p.Conference paper (Refereed)
    Abstract [en]

    As cities are growing the need for complementary sub centres increases, both in order to distribute amenities and to make resources more accessible for citizens, as well as to relieve the pressure on the city core. Such planning strategy, a kind of decentralized concentration, has been seen as a mean for holding back urban sprawl in Stockholm. Lately, urban centres are also argued to contribute to the development of more equal living conditions making opportunities, service, and urban life accessible also in more peripheral urban locations. The values of ‘suburban urbanities’ has also been highlighted in a way that reach far beyond the commercial activities (Vaughan 2015).The Regional planning authority in Stockholm as well as the City of Stockholm identifies a number of regional subcentres and ‘urban boulevards’ that should connect the city since and make it less fragmented. The social incentive for this strategy is prominent in both plans. However, these subcentres are dependent on urban centrality which needs to be taken into consideration.The strength, or the success, of a subcentre is partly influenced by urban design interventions and is argued to be related to 1) the configurative properties (distribution of space) and 2) land use parameters and density (distribution in and through space) (Koch 2016; Hillier 1999; Vaughan 2010). In order to increase the understanding for what urban design interventions that may be efficient, this paper will draw from the concepts developed by Stan Allen (1999) of point, line and field and John McMorrough (2001). The combination of the configurative perspective and the point-line-field perspective is argued to contribute with knowledge of how urban form generates and supports the emergence of urban centrality and the development of subcentres with implications not only for consumption and mobility, but also for social outcomes such as urban life and equal living conditions. The empirical application aims to illustrate how configurative analysis complement the point-line-field theory in describing the character of the centres and the findings are argued to contribute to the identification of more precise and efficient urban design interventions of how to develop the centres.

  • Koch, Daniel
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Architecture.
    Legeby, Ann
    KTH, School of Architecture and the Built Environment (ABE), Architecture, Urban Design.
    Abshirini, Ehsan
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geoinformatics.
    Perspectives on Culture: to witness, engage with, show, or do in cities2017In: Proceedings: 11th International Space Syntax Symposium / [ed] Teresa Heitor, Miguel Serra, João Pinelo Silva, Maria Bacharel, Luisa Cannas da Silva, INSTITUTO SUPERIOR TÉCNICO , 2017, 130.1-130.15 p.Conference paper (Refereed)
    Abstract [en]

    This paper addresses how ‘culture’ is or can be present in a city, where culture is understood in a wide sense as cultural activities and output of creative activity as well as partaking in or making use of the same. The main line of argument is that this requires consideration of how to work with configurational analysis, which has implications for a wider set of issues but made apparent in the specific focus.

    While this is anchored in empirical analysis, the main point is a theoretical-methodological discussion. In short, the paper proposes a model where culture needs to be understood from four perspectives—to witness, to engage with, to show, and to do—since these are differently related to the built environment in the conditions for how they appear, what effects they might have, and in what ways they are affected by and affect urban environments.

    Specifically, the empirical analyses point to how inequalities between areas can be understood. The conditions for making sculptures and how this affects and is affected by its surrounding, simply put, is different from the effects and conditions for the placing of public sculptures, as are their effects on public and private life.

    By use of specific and particular examples of activities or outputs, the article will also highlight qualitative aspects that need to be considered in relation to more precisely what kind of ‘culture’ that is intended to be supported, and how this relates to questions of democratic development and social equality.

  • Kasvayee, Keivan Amiri
    Jönköping University, School of Engineering, JTH, Materials and Manufacturing. Jönköping University, School of Engineering, JTH. Research area Materials and manufacturing – Casting.
    On the deformation behavior and cracking of ductile iron; effect of microstructure2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis focuses on the effect of microstructural variation on the mechanical properties and deformation behavior of ductile iron. To research and determine these effects, two grades of ductile iron, (i) GJS-500-7 and (ii) high silicon GJS-500-14, were cast in a geometry containing several plates with different section thicknesses in order to produce microstructural variation. Microstructural investigations as well as tensile and hardness tests were performed on the casting plates. The results revealed higher ferrite fraction, graphite particle count, and yield strength in the high silicon GJS-500-14 grade compared to the GJS-500-7 grade.

    To study the relationship between the microstructural variation and tensile behavior on macroscale, tensile stress-strain response was characterized using the Ludwigson equation. The obtained tensile properties were modeled, based on the microstructural characteristics, using multiple linear regression and analysis of variance (ANOVA). The models showed that silicon content, graphite particle count, ferrite fraction, and fraction of porosity are the major contributing factors that influence tensile behavior. The models were entered into a casting process simulation software, and the simulated microstructure and tensile properties were validated using the experimental data. This enabled the opportunity to predict tensile properties of cast components with similar microstructural characteristics.

    To investigate deformation behavior on micro-scale, a method was developed to quantitatively measure strain in the microstructure, utilizing the digital image correlation (DIC) technique together with in-situ tensile testing. In this method, a pit-etching procedure was developed to generate a random speckle pattern, enabling DIC strain measurement to be conducted in the matrix and the area between the graphite particles. The method was validated by benchmarking the measured yield strength with the material’s standard yield strength.

    The microstructural deformation behavior under tensile loading was characterized. During elastic deformation, strain mapping revealed a heterogeneous strain distribution in the microstructure, as well as shear bands that formed between graphite particles. The crack was initiated at the stress ranges in which a kink occurred in the tensile curve, indicating the dissipation of energy during both plastic deformation and crack initiation. A large amount of strain localization was measured at the onset of the micro-cracks on the strain maps. The micro-cracks were initiated at local strain levels higher than 2%, suggesting a threshold level of strain required for micro-crack initiation.

    A continuum Finite Element (FE) model containing a physical length scale was developed to predict strain on the microstructure of ductile iron. The material parameters for this model were calculated by optimization, utilizing the Ramberg-Osgood equation. The predicted strain maps were compared to the strain maps measured by DIC, both qualitatively and quantitatively. To a large extent, the strain maps were in agreement, resulting in the validation of the model on micro-scale.

    In order to perform a micro-scale characterization of dynamic deformation behavior, local strain distribution on the microstructure was studied by performing in-situ cyclic tests using a scanning electron microscope (SEM). A novel method, based on the focused ion beam (FIB) milling, was developed to generate a speckle pattern on the microstructure of the ferritic ductile iron (GJS-500-14 grade) to enable quantitative DIC strain measurement to be performed. The results showed that the maximum strain concentration occurred in the vicinity of the micro-cracks, particularly ahead of the micro-crack tip.

  • Langefeld, Carl D.
    et al.
    Ainsworth, Hannah C.
    Graham, Deborah S. Cunninghame
    Kelly, Jennifer A.
    Comeau, Mary E.
    Marion, Miranda C.
    Howard, Timothy D.
    Ramos, Paula S.
    Croker, Jennifer A.
    Morris, David L.
    Sandling, Johanna K.
    Almlof, Jonas Carlsson
    Acevedo-Vasquez, Eduardo M.
    Alarcon, Graciela S.
    Babini, Alejandra M.
    Baca, Vicente
    Bengtsson, Anders A.
    Berbotto, Guillermo A.
    Bijl, Marc
    Brown, Elizabeth E.
    Brunner, Hermine I.
    Cardiel, Mario H.
    Catoggio, Luis
    Cervera, Ricard
    Cucho-Venegas, Jorge M.
    Rantapää Dahlqvist, Solbritt
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Rheumatology.
    D'Alfonso, Sandra
    Da Silva, Berta Martins
    de la Rua Figueroa, Inigo
    Doria, Andrea
    Edberg, Jeffrey C.
    Endreffy, Emoke
    Esquivel-Valerio, Jorge A.
    Fortin, Paul R.
    Freedman, Barry I.
    Frostegard, Johan
    Garcia, Mercedes A.
    Garcia de la Torre, Ignacio
    Gilkeson, Gary S.
    Gladman, Dafna D.
    Gunnarsson, Iva
    Guthridge, Joel M.
    Huggins, Jennifer L.
    James, Judith A.
    Kallenberg, Cees G. M.
    Kamen, Diane L.
    Karp, David R.
    Kaufman, Kenneth M.
    Kottyan, Leah C.
    Kovacs, Laszlo
    Laustrup, Helle
    Lauwerys, Bernard R.
    Li, Quan-Zhen
    Maradiaga-Cecena, Marco A.
    Martin, Javier
    McCune, Joseph M.
    McWilliams, David R.
    Merrill, Joan T.
    Miranda, Pedro
    Moctezuma, Jose F.
    Nath, Swapan K.
    Niewold, Timothy B.
    Orozco, Lorena
    Ortego-Centeno, Norberto
    Petri, Michelle
    Pineau, Christian A.
    Pons-Estel, Bernardo A.
    Pope, Janet
    Raj, Prithvi
    Ramsey-Goldman, Rosalind
    Reveille, John D.
    Russell, Laurie P.
    Sabio, Jose M.
    Aguilar-Salinas, Carlos A.
    Scherbarth, Hugo R.
    Scorza, Raffaella
    Seldin, Michael F.
    Sjowall, Christopher
    Svenungsson, Elisabet
    Thompson, Susan D.
    Toloza, Sergio M. A.
    Truedsson, Lennart
    Tusie-Luna, Teresa
    Vasconcelos, Carlos
    Vila, Luis M.
    Wallace, Daniel J.
    Weisman, Michael H.
    Wither, Joan E.
    Bhangale, Tushar
    Oksenberg, Jorge R.
    Rioux, John D.
    Gregersen, Peter K.
    Syvanen, Ann-Christine
    Ronnblom, Lars
    Criswell, Lindsey A.
    Jacob, Chaim O.
    Sivils, Kathy L.
    Tsao, Betty P.
    Schanberg, Laura E.
    Behrens, Timothy W.
    Silverman, Earl D.
    Alarcon-Riquelme, Marta E.
    Kimberly, Robert P.
    Harley, John B.
    Wakeland, Edward K.
    Graham, Robert R.
    Gaffney, Patrick M.
    Vyse, Timothy J.
    Transancestral mapping and genetic load in systemic lupus erythematosus2017In: Nature Communications, ISSN 2041-1723, E-ISSN 2041-1723, Vol. 8, 16021Article in journal (Refereed)
    Abstract [en]

    Systemic lupus erythematosus (SLE) is an autoimmune disease with marked gender and ethnic disparities. We report a large transancestral association study of SLE using Immunochip genotype data from 27,574 individuals of European (EA), African (AA) and Hispanic Amerindian (HA) ancestry. We identify 58 distinct non-HLA regions in EA, 9 in AA and 16 in HA (similar to 50% of these regions have multiple independent associations); these include 24 novel SLE regions (P < 5 x 10(-8)), refined association signals in established regions, extended associations to additional ancestries, and a disentangled complex HLA multigenic effect. The risk allele count (genetic load) exhibits an accelerating pattern of SLE risk, leading us to posit a cumulative hit hypothesis for autoimmune disease. Comparing results across the three ancestries identifies both ancestry-dependent and ancestry-independent contributions to SLE risk. Our results are consistent with the unique and complex histories of the populations sampled, and collectively help clarify the genetic architecture and ethnic disparities in SLE.

  • Public defence: 2017-09-12 13:15 K3, Norrköping
    Steins, Krisjanis
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Towards Increased Use of Discrete-Event Simulation for Hospital Resource Planning2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Health care systems in many countries are experiencing a growing demand while their resources remain limited. The discrepancy between demand and capacity creates many problems – long waiting times for treatment, overcrowding in hospital wards, high workload, etc. More efficient delivery of health care services can be achieved by better planning of its resources so that the mismatch between demand and capacity is minimized. Planning health care resources, including hospital resources, is difficult due to system complexity and variability in both resource availability and demand. Discrete-event simulation and other operational research methods can be used for solving planning problems in health care, and have been gaining increased attention from researchers during recent decades. Despite the growing number of academic publications, simulation appears to be less used in health care than in other application areas and only a small proportion of simulation studies is actually implemented.

    The aim of this thesis is to contribute to increased use of discrete-event simulation in hospital resource planning. The separate studies regarding intensive care unit capacity planning, operating room allocation strategies and the management of emergency patient flow in a radiology department highlight both the possibilities and the requirements for practical application of discrete-event simulation in hospital resource planning. The studies are described in five papers.

    In the first paper, the relationship between intensive care unit (ICU) occupancy and patient outcomes was investigated and the results showed that risk adjusted mortality was higher in the group of patients who were treated during high levels of occupancy. This indicates that appropriate planning of ICU resources is necessary to avoid adverse effects on patient outcomes.

    In the second paper, analysis of a relatively simple care chain consisting of two hospital departments – emergency and radiology – revealed a process that was not very well defined and measured. Investigation into data availability uncovered disparate information systems storing incompatible and fragmented data. It suggests that the current degree of process orientation and the current IT infrastructure does not enable efficient use of quantitative process analysis and management tools such as simulation.

    In the third paper, the value and possibilities of using simulation modelling in hospital resource planning were examined through the development and use of a simulation model for improved operating room time allocation and patient flow in a hospital operating department. The model was initially used for studying overcrowding in a post-anaesthesia care unit. Advanced planning logic implemented in the model enabled evaluation of several different scenarios aiming to improve the utilization of operating room resources. The results showed that it is possible to achieve slightly better and more even resource utilization, as well as provide greater flexibility in scheduling operations.

    In the fourth paper, a generic ICU model was developed and validated using data from four different hospital ICUs. The model was adapted and calibrated stepwise in order to identify important parameters and their values to obtain a match between model predictions and actual data. The study showed that in presence of high quality data and well defined process logic it is possible to develop a generic ICU simulation model that could provide accurate decision support for planning critical care resources.

    In the fifth paper, a number of factors that can contribute to successful implementation of simulation results in health care were identified. The timing of the simulation study must be right to support a critical decision, the benefit from implementation should clearly outweigh the cost of making the necessary changes and the model should be thoroughly validated to increase the credibility of the results. Staff involvement in simulation modelling activities, availability of good quality data, as well as proper incentives to improve the system contribute to implementation as well. These findings can help in establishing the conditions for successful implementation in future applications of simulation modelling in health care.

  • Public defence: 2017-09-08 13:15 Hörsal 2, Uppsala
    Molinder, Jakob
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Economic History.
    Interregional Migration, Wages and Labor Market Policy: Essays on the Swedish Model in the Postwar Period2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The Swedish model is perceived as a successful framework for combining rapid labor market adjustment with low inequality. Formulated by Gösta Rehn and Rudolf Meidner and implemented from the 1950s, it has been associated with the peak in economic restructuring and interregional migration during the 1960s. However, there is little empirical evidence for this. This thesis consists of an introduction and four essays. It explores three aspects of the model from a long-run perspective: interregional migration, wage dispersion and labor market policy.

    Essay I uses new data to track interregional migration rates in the postwar period (1945-1985). The results show that the responsiveness of interregional migration to local labor market conditions remained stable over time; it was neither higher during the 1960s nor lower when migration declined after 1970.

    Essay II employs a regression-decomposition framework to analyze the evolution of wage dispersion. The results suggest that wage dispersion was stable from centralized bargaining’s introduction in 1956 to the late 1960s. Afterwards, there was a rapid decline, likely because of solidaristic bargaining.

    Essay III contrasts the implementation of the active labor market policy to regional policy. Following a decisive shift around 1970, the focus on north to south mobility was replaced with policies to stimulate northern employment. Declining rural support for the Social Democrats and electoral competition from the Center Party caused this shift.

    Finally, Essay IV is a case study about mobility subsidy usage in Västernorrland County using sources on relocation allowances from 1965, 1970 and 1975. The results indicate that in the 1960s there was strong selection into the program by young persons with good labor market prospects. However, the program’s use did not change after the regional policy shift in the early 1970s.

    The collective results suggest that the policies associated with the Swedish model were minor for economic restructuring patterns. The migrations of the 1960s and the decline in regional disruptions after 1970 should instead be explained by studying the consequences of structural changes, how regions were progressively affected differently and the possible role that government policies played in directing demand for labor across space.

  • Juter, Kristina
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Research environment Learning in Science and Mathematics (LISMA).
    University students’ understandings of concept relations and preferred representations of continuity and differentiability2017In: Proceedings of the Tenth Congress of the European Society for Researchin Mathematics Education (CERME10, February 1 – 5, 2017). Dublin, Ireland / [ed] Dooley, T. & Gueudet, G, Dublin, Ireland: DCU Institute of Education and ERME , 2017Conference paper (Refereed)
    Abstract [en]

    The aim of the study reported in this paper is to investigate how students understand continuity and differentiability during and after a calculus course. The students’ choices of representations, both claimed and acted, were also studied. The study is part of a larger study of four student groups taking a calculus course. 207 students answered a questionnaire during the course and of them, 11 were interviewed after the course (the ones in this paper). Answers in questionnaires and interviews were categorised and compared. All students who preferred formal theoretical representations, and only those students, were able to produce formal proofs. The students’ stated and acted preferencesof representations were quite coherent, with only a few inconsistencies.

  • Nordström, Jan
    et al.
    Linköping University, Department of Mathematics, Computational Mathematics. Linköping University, Faculty of Science & Engineering.
    La Cognata, Cristina
    Linköping University, Department of Mathematics, Computational Mathematics. Linköping University, Faculty of Science & Engineering.
    Energy Stable Boundary Conditions for the Nonlinear Incompressible Navier-Stokes Equations2017Report (Other academic)
    Abstract [en]

    The nonlinear incompressible Navier-Stokes equations with boundary conditions at far fields and solid walls is considered. Two different formulations of boundary conditions are derived using the energy method. Both formulations are implemented in both strong and weak form and lead to an estimate of the velocity field. Equipped with energy bounding boundary conditions, the problem is approximated by using difference operators on summation-by-parts form and weak boundary and initial conditions. By mimicking the continuous analysis, the resulting semi-discrete as well as fully discrete scheme are shown to be provably stable, divergence free and high-order accurate.

  • La Cognata, Cristina
    et al.
    Linköping University, Department of Mathematics, Computational Mathematics. Linköping University, Faculty of Science & Engineering.
    Nordström, Jan
    Linköping University, Department of Mathematics, Computational Mathematics. Linköping University, Faculty of Science & Engineering.
    Spectral analysis of the incompressible Navier-Stokes equations with different boundary conditions2017Report (Other academic)
    Abstract [en]

    The influence of boundary conditions on the spectrum of the incompressible Navier-Stokes equations is studied. The spectra associated to different types of boundary conditions are derived using the Fourier-Laplace technique. In particular, the effect of various combinations of generalized in- and outgoing variables on the convergence to the steady state is investigated. The boundary conditions are analysed in both the continuous and semi-discrete problems. In the latter, high-order schemes in summation-by-parts form with weakly imposed boundary conditions are used to approximate the equations. Numerical calculations are performed and show that the discrete behaviour agrees with the theoretical analysis.

  • Zimmerman, Malin
    et al.
    Enes, Sara Rolandsson
    Skarstrand, Hanna
    Pourhamidi, Kaveh
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine.
    Gottsater, Anders
    Wollmer, Per
    Rolandsson, Olov
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine.
    Westergren-Thorsson, Gunilla
    Dahlin, Lars B.
    Temporal trend of autonomic nerve function and HSP27, MIF and PAI-1 in type 1 diabetes2017In: Journal of clinical and translational endocrinology, ISSN 2214-6237, Vol. 8, 15-21 p.Article in journal (Refereed)
    Abstract [en]

    Aim: Diabetes mellitus type 1 (T1D) has numerous complications including autonomic neuropathy, i.e. dysfunction of the autonomous nervous system. This study focuses on Heat Shock Protein 27 (HSP27), Macrophage Migration Inhibitory Factor (MIF), Plasminogen Activator Inhibitor-1 (PAI-1) and HbA1c and their possible roles in effects of diabetes on the autonomic nervous system.

    Methods: Patients with T1D (n = 32, 41% women) were recruited in 1985 and followed up on four occasions (1989, 1993, 1998, and 2005). Autonomic function was tested using expiration/inspiration (E/I-ratio). Blood samples, i.e. HSP27 (last three occasions), MIF, PAI-1 (last two occasions) and HbA1c (five occasions), were analyzed.

    Results: Autonomic nerve function deteriorated over time during the 20-year-period, but levels of HSP27, MIF, and PAI-1 were not associated with cardiovascular autonomic neuropathy. MIF and PAI-1 were lower in T1D than in healthy controls in 2005. Increased HbA1c correlated with a decrease in E/I-ratio.

    Conclusions: Neither the neuroprotective substance HSP27 nor the inflammatory substances, MIF and PAI-1 were associated with measures of cardiovascular autonomic nerve function, but a deterioration of such function was observed in relation to increasing HbA1c in T1D during a 20-year follow-up period. Improved glucose control might be associated with protection against autonomic neuropathy in T1D.

  • Lindh, Erik L.
    et al.
    RISE, Innventia.
    Terenzi, Camilla
    Salmén, Lennart
    RISE, Innventia.
    Furo, I
    Water in cellulose: evidence and identification of immobile and mobile adsorbed phases by 2H MAS NMR2017In: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084, Vol. 19, 4360-4369 p.Article in journal (Refereed)
    Abstract [en]

    The organization of water molecules adsorbed onto cellulose and the supramolecular hydrated structure of microfibril aggregates represents, still today, one of the open and complex questions in the physical chemistry of natural polymers. Here, we investigate by 2H MAS NMR the mobility of water molecules in carefully 2H-exchanged, and thereafter re-dried, microcrystalline cellulose. By subtracting the spectral contribution of deuteroxyls from the spectrum of hydrated cellulose, we demonstrate the existence of two distinct 2H2O spectral populations associated with mobile and immobile water environments, between which the water molecules do not exchange at the NMR observation time scale. We conclude that those two water phases are located at differently-accessible adsorption sites, here assigned to the cellulose surfaces between and within the microfibril aggregates, respectively. The superior performance of 2H MAS NMR encourages further applications of the same method to other complex systems that expose heterogeneous hygroscopic surfaces, like wood cell walls.

  • Liljegren, Henrik
    et al.
    Stockholm University, Faculty of Humanities, Department of Linguistics, General Linguistics.
    Khan, Afsar Ali
    Forum for Language Initiatives.
    Khowar: Illustrations of the IPA2017In: Journal of the International Phonetic Association, ISSN 0025-1003, E-ISSN 1475-3502, Vol. 47, no 2, 219-229 p.Article in journal (Refereed)
    Abstract [en]

    Khowar (ISO 639-3: khw) is an Indo-Aryan language spoken by 200,000–300,000 (Decker 1992: 31–32; Bashir 2003: 843) people in Pakistan's Khyber Pakhtunkhwa Province (formerly North-West Frontier Province). The majority of the speakers are found in Chitral (a district and erstwhile princely state bordering Afghanistan, see Figure 1), where the language is used as a lingua franca, but there are also important pockets of speaker groups in adjacent areas of Gilgit-Baltistan and Swat District as well as a considerable number of recent migrants to larger cities such as Peshawar and Rawalpindi (Decker 1992: 25–26). Its closest linguistic relative is Kalasha, a much smaller language spoken in a few villages in southern Chitral (Morgenstierne 1961: 138; Strand 1973: 302, 2001: 252). While Khowar has preserved a number of features (phonological, morphological as well as lexical) now lost in other Indo-Aryan languages of the surrounding Hindukush-Karakoram mountain region, it has, over time, incorporated a massive amount of lexical material from neighbouring or influential Iranian languages (Morgenstierne 1936) – and with it, new phonological distinctions. Certain features might also be attributable to formerly dominant languages (e.g. Turkic), or to linguistic substrates, either in the form of, or related to, the language isolate Burushaski, or other, now extinct, languages previously spoken in the area (Morgenstierne 1932: 48, 1947: 6; Bashir 2007: 208–214). There is relatively little dialectal variation among the speakers in Chitral itself, probably attributable to the relative recency of the present expansion of the language (Morgenstierne 1932: 50).

  • Gaziano, Thomas A.
    et al.
    Abrahams-Gessel, Shafika
    Gomez-Olive, F. Xavier
    Wade, Alisha
    Crowther, Nigel J.
    Alam, Sartaj
    Manne-Goehler, Jennifer
    Kabudula, Chodziwadziwa W.
    Wagner, Ryan
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Epidemiology and Global Health. University of the Witwatersrand, Johannesburg, South Africa ; INDEPTH Network, Accra, Ghana ; Africa Wits-INDEPTH Genomic Studies of Cardiovascular Disease, University of the Witwatersrand.
    Rohr, Julia
    Montana, Livia
    Kahn, Kathleen
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Epidemiology and Global Health. University of the Witwatersrand, Johannesburg, South Africa ; INDEPTH Network, Accra, Ghana ; Africa Wits-INDEPTH Genomic Studies of Cardiovascular Disease, University of the Witwatersrand.
    Baernighausen, Till W.
    Berkman, Lisa F.
    Tollman, Stephen
    Cardiometabolic risk in a population of older adults with multiple co-morbidities in rural south africa: the HAALSI (Health and Aging in Africa: longitudinal studies of INDEPTH communities) study2017In: BMC Public Health, ISSN 1471-2458, E-ISSN 1471-2458, Vol. 17, 206Article in journal (Refereed)
    Abstract [en]

    Background: A consequence of the widespread uptake of anti-retroviral therapy (ART) is that the older South African population will experience an increase in life expectancy, increasing their risk for cardiometabolic diseases (CMD), and its risk factors. The long-term interactions between HIV infection, treatment, and CMD remain to be elucidated in the African population. The HAALSI cohort was established to investigate the impact of these interactions on CMD morbidity and mortality among middle-aged and older adults. Methods: We recruited randomly selected adults aged 40 or older residing in the rural Agincourt sub-district in Mpumalanga Province. In-person interviews were conducted to collect baseline household and socioeconomic data, self-reported health, anthropometric measures, blood pressure, high-sensitivity C-reactive protein (hsCRP), HbA1c, HIV-status, and point-of-care glucose and lipid levels. Results: Five thousand fifty nine persons (46.4% male) were enrolled with a mean age of 61.7 +/- 13.06 years. Waist-to- hip ratio was high for men and women (0.92 +/- 0.08 vs. 0.89 +/- 0.08), with 70% of women and 44% of men being overweight or obese. Blood pressure was similar for men and women with a combined hypertension prevalence of 58.4% and statistically significant increases were observed with increasing age. High total cholesterol prevalence in women was twice that observed for men (8.5 vs. 4.1%). The prevalence of self-reported CMD conditions was higher among women, except for myocardial infarction, and women had a statistically significantly higher prevalence of angina (10.82 vs. 6.97%) using Rose Criteria. The HIV- persons were significantly more likely to have hypertension, diabetes, or be overweight or obese than HIV+ persons. Approximately 56% of the cohort had at least 2 measured or self-reported clinical co-morbidities, with HIV+ persons having a consistently lower prevalence of co-morbidities compared to those without HIV. Absolute 10-year risk cardiovascular risk scores ranged from 7.7-9.7% for women and from 12.5-15.3% for men, depending on the risk score equations used. Conclusions: This cohort has high CMD risk based on both traditional risk factors and novel markers like hsCRP. Longitudinal follow-up of the cohort will allow us to determine the long-term impact of increased lifespan in a population with both high HIV infection and CMD risk.

  • Public defence: 2017-09-08 10:00 M3, Stockholm
    Topel, Monika
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Improving Concentrating Solar Power Plant Performance through Steam Turbine Flexibility2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The amount of incoming solar energy to earth is greater than any other source. Among existing technologies to harness solar energy there is concentrating solar power (CSP). One advantage of CSP is that is dispatchable, meaning that it can provide power even when the sun is not shining. However, CSP is undergoing challenges which hinder its development such as operating variabilities caused by the fluctuations of the sun or the fact that these systems are not yet cost competitive with respect to other technologies.  

    One way of improving the performance of CSP plants (CSPPs) is by increasing their operational flexibility, specifically their capability for fast starts. In this way it is possible for the CSPP to harness the solar energy as soon as possible, thus producing more energy and increasing its profitability. Over 90% of CSPPs use a steam turbine to generate electricity. Steam turbines are not currently designed with the flexibility required by the CSP application. Steam turbine start-up is limited by thermal stress and differential expansion. If not carefully controlled, these phenomena either consume lifetime or even result in machine failure.

    The aim of this work was to understand the improvement potential of steam turbine start-up and quantify this in terms of CSPP performance indicators. For this, a thermo-mechanical steam turbine model was developed and validated. The model was then used to analyze potential improvements and thermal constraints to steam turbine start-up operation. Furthermore, a CSP plant techno-economic model was developed including steam turbine details. This modeling approach including two levels of detail allowed for the particularities of the component to be included within the dynamics of the plant and thus be able to connect the perspectives of the equipment manufacturer with those of the plant operator. Reductions of up to 11.4% in the cost of electricity were found in the studies carried out.

  • Dalmar, Abdirisak Ahmed
    et al.
    Hussein, Abdullahi Sheik
    Walhad, Said Ahmed
    Ibrahim, Abdirashid Omer
    Abdi, Abshir Ali
    Ali, Mohamed Khalid
    Erlandsson, Kerstin
    Dalarna University, School of Education, Health and Social Studies, Caring Science/Nursing.
    Klingberg-Allvin, Marie
    Dalarna University, School of Education, Health and Social Studies, Caring Science/Nursing.
    Osman, Fatumo
    Dalarna University, School of Education, Health and Social Studies, Caring Science/Nursing.
    Wall, Stig
    Rebuilding research capacity in fragile states: the case of a Somali-Swedish global health initiative2017In: Global Health Action, ISSN 1654-9716, E-ISSN 1654-9880, Vol. 10, no 1, 1348693Article in journal (Refereed)
    Abstract [en]

    This paper presents an initiative to revive the previous Somali-Swedish Research Cooperation, which started in 1981 and was cut short by the civil war in Somalia. A programme focusing on research capacity building in the health sector is currently underway through the work of an alliance of three partner groups: six new Somali universities, five Swedish universities, and Somali diaspora professionals. Somali ownership is key to the sustainability of the programme, as is close collaboration with Somali health ministries. The programme aims to develop a model for working collaboratively across regions and cultural barriers within fragile states, with the goal of creating hope and energy. It is based on the conviction that health research has a key role in rebuilding national health services and trusted institutions.

  • Recensioner1998In: Sociologisk forskning, ISSN 0038-0342, Vol. 35, no 3-4, 211-247 p.Article, book review (Other academic)
  • Economou, Konstantin
    et al.
    Linköpings universitet.
    Forstorp, Per-Anders
    Linköpings universitet.
    Bourdieus moraliska panik1998In: Sociologisk forskning, ISSN 0038-0342, Vol. 35, no 3-4, 195-210 p.Article in journal (Refereed)
  • Svensson, Göran
    Uppsala universitet.
    Mediekritik och mediemakt: Bidrag till en kartering av mediekritikens fält1998In: Sociologisk forskning, ISSN 0038-0342, Vol. 35, no 3-4, 171-194 p.Article in journal (Refereed)
    Abstract [en]

    Media power and media criticism: Towards a mapping of the field of media criticism

    In the late 90s critical debate and research on the media have gained wide attention. Media criticism and critique is becoming a central political, social and scientific issue. In the article the concept of media criticism is discussed. Media criticism is interpreted as public discourse assessing the media and media impact. Beyond a dialogue on media policy and media practice, criticism offers highly polarized and partly mystifying accounts of the media and its social and cultural impact. The heated debate on media is interpreted as part of a social struggle between different social institutions (markets, politics, science and media) and as different models for action and knowledge. New forms and arenas for media criticism are also suggested and discussed.

  • Ekström, Mats
    Högskolan i Örebro.
    Attraktionens tv-journalistik1998In: Sociologisk forskning, ISSN 0038-0342, Vol. 35, no 3-4, 143-170 p.Article in journal (Refereed)
    Abstract [en]

    TV-journalism of attraction

    The contemporary media society is characterized by an overabundance of information, messages and images, but a shortage of attention. The competition for the attention of potential audiences, and the problem of audience appeal, has become an increasingly important aspect of journalism and media production. Journalism that does not succeed in this competition is a dead journalism. This article presents a conceptual framework for studies of TV journalism as communication, including different intentions, strategies applied to appeal to viewers, processes of production, bases for audience involvement, roles and relations. I differentiate three modes of communication: information, story-telling and attractions. The article devotes most attention to the concept of attraction as it is the most theoretically innovative of the three. The concept TV journalism of attraction is introduced and elaborated as an important concept in media and journalism studies.

  • Eide, Martin
    Universitetet i Bergen.
    Det journalistiske mistaket1998In: Sociologisk forskning, ISSN 0038-0342, Vol. 35, no 3-4, 123-141 p.Article in journal (Refereed)
    Abstract [en]

    The journalistic fallacy

    An expansion of ”media logic” and media strategies in private and public sectors of society is the point of departure for this paper. The power of journalism is a force drawn upon by a wide range of social agents. The question is whether what appears as a victory of journalistic formats and frames of understanding simultaneously is a journalistic defeat. The paper identifies and discusses current aspects of journalistic practice and ideology which might constitute a journalistic fallacy. Among these aspects is the role of the journalist as an impressario of public issues and possible populistic interpretations of this role. Another related aspect is a restricted and vulgar understanding of power involved in a current conception of journalism as ideology. The expansionof a certain service ideology within the mass media and in other domains of public life is also discussed. The journalistic fallacy can be conducted as well by other social agents as by journalists. Implications of this sour victory of journalism is discussed with reference to the Norwegian social philosopher Hans Skjervheim’s writings, especially on the problems of instrumentalism in social life.

  • Ganetz, Hillevi
    Södertörns högskola.
    Medier och (populär) kultur1998In: Sociologisk forskning, ISSN 0038-0342, Vol. 35, no 3-4, 101-122 p.Article in journal (Refereed)
    Abstract [en]

    Media and (popular) culture

    This article is a discussion of media in relation to culture and popular culture. Internationally as well as in Sweden, there has been a ‘cultural turn’ in media research, where theories and methods have been increasingly influenced by cultural studies. Of particular importance is the cultural studies’ concepts of culture as lived experience or as practices through which meaning is produced and shared between people. Meaning is expressed through different symbolic forms that in our society to a high extent are carried by media. An example is rock lyrics, a genre of mediated communication, i.e. symbolic expressions mediated by media like phonograms, radio, television or video. They are also elements of popular music, which is a part of popular culture - a phenomenon closely connected to the rise of modernity. Popular culture is defined as massproduced cultural products which are used and spread among large groups of the population and which are generally classified by the dominant taste as having little value. The article ends with an analysis inspired by cultural studies of a mediated symbolic expression: two rock texts by the famous Swedish rock artist Eva Dahlgren. The author claims that it is possible to reveal crucial traits and tendencies of the cultural context through such an analysis of the unique mediated text.

  • Löwander, Birgitta
    Umeå universitet.
    Rasism och antirasism på dagordningen - studier av televisionens nyhetsrapportering i början av 1990-talet1998In: Sociologisk forskning, ISSN 0038-0342, Vol. 35, no 3-4, 85-100 p.Article in journal (Refereed)
    Abstract [en]

    Racism and anti-racism on the agenda. Studies of Swedish television news in the beginning of the 1990s

    The way the news defines social phenomena has significance for our collective imaginations. When the news broadcasters are about to make the world comprehensible and accessible to the audience, they have to consider and extend what is already commonly known and accepted as true. How the news media make sense of racism and anti-racism was focused in a research project comprising several substudies and different empirical data. The public television news broadcast from the beginning of the 1990s was used as the basis. This was a period when the political climate regarding refugees in Sweden was hardening and racial violence towards immigrants and refugees increased. The author's main conclusion is that, for the news to be effective and credible, the news media follow, relatively uncritically, the conventions that they themselves have created. Racism is defined as racial violence, and in the news coverage racism is reduced to a form of criminal behaviour or a pathological defect. The whole field of research that in recent decades has debated the complexity of racism remains invisible. Anti-racism, at the same time, is represented as a protest against racial violence. News coverage of racism and anti-racism, accordingly, constitutes part ofa common sense ideology of normality opposed to extremism, where anti-racist demonstrations are interpreted in terms of extremism rather than as protest against inequity or as a defence of human rights. The news media are the guardians of social control and stability, the study concludes, acting to restore the national self-portrait of a tolerant nation.

  • Hålenius, Ulf
    et al.
    Swedish Museum of Natural History, Department of Geology.
    Hatert, Frédéric
    Université de Liège, Belgium..
    Pasero, Marco
    Università di Pisa, Italy..
    Mills, Stuart J.
    Museum Victoria, Melbourne, Australia..
    IMA Commission on New Minerals, Nomenclature and Classification (CNMNC) Newsletter 382017In: Mineralogical magazine, ISSN 0026-461X, E-ISSN 1471-8022, Vol. 81, no 4, 1033-1038 p.Article in journal (Other academic)
  • Rasmussen, Terje
    Universitetet i Oslo.
    Nærværets moral i distansenes verden1998In: Sociologisk forskning, ISSN 0038-0342, Vol. 35, no 3-4, 61-84 p.Article in journal (Refereed)
    Abstract [en]

    The morality of closeness in a world of distances

    This article addresses the potentials and hindrances of moral relationships in contemporary world society, as they increasingly are mediated through modern mass media. Of particular interest is Levinasian ethics of responsibility stemming from the face of the Other. It particularly discusses the postmodern version of such ethics as it has been interpreted and developed sociologically by Zygmunt Bauman. The essay consists of three parts: First, the image of a post-ethical world in the media is interpreted through the perspective of Bauman. Second, the question discussed is whether the Other can be morally perceived through the mediation of modern technical media, particularly television. Third, the dilemma of the appearance of the Third is discussed: Can a levinasian ethics be a macro-ethics? Generally, the essay constitutes a critical comment to Bauman’s far-reaching ambitions on behalf of anethics of closeness.

  • Ekecrantz, Jan
    Stockholms universitet.
    Modernitet, globalisering och medier1998In: Sociologisk forskning, ISSN 0038-0342, Vol. 35, no 3-4, 33-60 p.Article in journal (Refereed)
    Abstract [en]

    Modernity, globalisation and media

    Conceptions of time and space lie at the heart of many prevalent discourses on modernity and globalization. These conceptions are variably based on ideas of modern media of communication having developed as part of technological and other transformations throughout the modern era. One major aim of the article is to scrutinize some of the literature that claims to establish historical links between modernity, globalization and the media. For one thing, it is asserted here that globalization is not simply a logical outcome of modernity. Depending on the chosen historical perspective, the relationship might be the contrary one - global interdependencies appearing prior to both early and late modernity. There is also a criticism of the spatialization turn in social and cultural theory. It does not capture the subtle dialectics of time and space as these dimensions are reconstituted by the media, not least on the global level. In this context and as an exposé of continuity vs. change arguments the author considers the critiques of media imperialism and postjournalism

  • Jansson, André
    Göteborgs universitet.
    Smakernas begränsade frihet: Om kulturindustrins makt över sin publik1998In: Sociologisk forskning, ISSN 0038-0342, Vol. 35, no 3-4, 7-31 p.Article in journal (Refereed)
    Abstract [en]

    The limited freedom of tastes - on the culture industry's power over its audiences

    Taking Horkheimer and Adorno’s Dialectic of Enlightenment as the main point of departure, this article deals with the question of the culture industry’s power to determine the cultural taste of audiences. Through an overview of literature within foremost political economy (especially about cultural imperialism) and cultural studies (focusing on the meaning creating processes of audiences), a re-evaluation of Horkheimer and Adorno’s original thesis is made. The article concludes that many of the core ideas of the Frankfurt school are still relevant to apply within cultural sociology and media studies. The culture industry’s power over its audiences lies in its potential to make the cultural content accessible to lots of people through the repetition and the successive transition of generic conventions. However, these ideas must be made more dynamic and less elitistic. This means that audiences must be considered as active producers of meaning, situated in specific sociocultural contexts. Without this revision, the perspective of Horkheimer and Adorno is far too rigid to make any good sense within the reflexive cultural climate of late modernity.

  • Ekström, Mats
    Örebro universitet.
    Förord1998In: Sociologisk forskning, ISSN 0038-0342, Vol. 35, no 3-4, 5-6 p.Article in journal (Other academic)
  • Ekström, Mats
    Örebro universitet.
    Sociologisk Forskning 1998:3-41998Collection (editor) (Refereed)