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  • Forsman, Åsa
    et al.
    Statens väg- och transportforskningsinstitut, Trafik och trafikant,TRAF, Trafiksäkerhet och trafiksystem, TST.
    Vadeby, Anna
    Statens väg- och transportforskningsinstitut, Trafik och trafikant,TRAF, Trafiksäkerhet och trafiksystem, TST.
    Gundlegård, David
    Linköpings universitet.
    Ringdahl, Rasmus
    Linköpings universitet.
    Utvärdering av hastighetsmätningar med blåtandssensorer: jämförelse med data från MCS (Motorway Control System)2018Rapport (Annet vitenskapelig)
    Abstract [sv]

    Syftet med det här projektet har varit att utvärdera hur väl hastighetsmätningar som beräknats med hjälp av data från blåtandssensorer stämmer överens med radarmätningar. Av speciellt intresse har varit att utvärdera om metoden skulle kunna användas vid före-efter studier av trafiksäkerhetsåtgärder som till exempel trafiksäkerhetskameror eller andra hastighetsdämpande åtgärder. Utvärderingen baseras på data från två mätplatser på E4:an strax norr om Stockholm.

    Resultaten från studien visar att:

    • Penetrationsgraden (andel blåtandspassager per passerat fordon) varierar mellan 12 och 16 procent beroende på plats och om det är vardag eller helg.

    • Blåtandsmätningarna ger stabila resultat med avseende på medelhastigheten på dygnsnivå. Jämförelser med MCS-data visar att resultaten från de två mätmetoderna följer varandra väl och differensen mellan metoderna är ungefär lika stor från dygn till dygn.

    • Hastighetsmätningar med blåtandssensorer bedöms vara tillräckligt tillförlitliga, på den studerade vägtypen, för att kunna användas i utvärderingar av olika trafiksäkerhetsåtgärder.

  • Disputas: 2018-06-12 09:00 Konferensrummet, Uppsala
    Wang, Juan
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinska vetenskaper, Arbets- och miljömedicin.
    Asthma and Rhinitis among Adults in Sweden and China: Risk Factors in the Home Environment2018Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The main aim of this thesis was to evaluate associations between selected home environment factors and asthma, rhinitis and respiratory symptoms among adults from Sweden, China and northern Europe. Two studies were performed in Sweden, one in China, and one longitudinal cohort study was performed in northern Europe. Dampness/mould was common, and was a main risk factor in all studies. Other risk factors for asthma symptoms in Sweden included window pane condensation in winter, multi-family buildings constructed from 1961-1975, rented apartments, environment tobacco smoke (ETS), and living in a colder climate zone. Higher ventilation flow in Sweden was associated with less asthma symptoms. Risk factors for rhinitis in Sweden included window pane condensation, a higher moisture load, concrete slab foundation constructed before 1991, multi-family buildings constructed from 1976-1985, rented apartments and living in densely populated areas. Risk factors for rhinitis in China included window pane condensation, recent redecoration, new furniture, presence of cockroaches, pet keeping, ETS and living near a main road or highway. Frequently cleaning of the home and putting beddings to sunshine were protective factors for rhinitis in China. Other risk factors for respiratory infections in Sweden included houses with a brick façade, window pane condensation, a higher moisture load, multi-family buildings constructed from 1976-1985, rented apartments and living in densely populated areas. Furthermore, dampness and mould, and mould odour were risk factors for onset of asthma and rhinitis in northern Europe. In conclusion, indoor dampness and mould can be a risk factor for asthma and rhinitis in Sweden, China and northern Europe. Certain construction years (1961-1985), ETS, recent redecoration, new furniture, living in urban areas and exposure to traffic air pollution can be risk factors for asthma, rhinitis or respiratory infections. A high ventilation flow and daily cleaning at home can be protective.

  • Eriksson, Leif
    et al.
    Nga, Nguyen T
    Hoa, Dinh T Phuong
    Duc, Duong M
    Bergström, Anna
    Wallin, Lars
    Högskolan Dalarna, Akademin Utbildning, hälsa och samhälle, Omvårdnad. Karolinska institutet; Göteborgs universitet.
    Målqvist, Mats
    Ewald, Uwe
    Huy, Tran Q
    Selling, Katarina Ekholm
    Secular trend, seasonality and effects of a community-based intervention on neonatal mortality: follow-up of a cluster-randomised trial in Quang Ninh province, Vietnam.2018Inngår i: Journal of Epidemiology and Community Health, ISSN 0143-005X, E-ISSN 1470-2738Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    BACKGROUND: Little is know about whether the effects of community engagement interventions for child survival in low-income and middle-income settings are sustained. Seasonal variation and secular trend may blur the data. Neonatal mortality was reduced in a cluster-randomised trial in Vietnam where laywomen facilitated groups composed of local stakeholders employing a problem-solving approach for 3 years. In this analysis, we aim at disentangling the secular trend, the seasonal variation and the effect of the intervention on neonatal mortality during and after the trial.

    METHODS: In Quang Ninh province, 44 communes were allocated to intervention and 46 to control. Births and neonatal deaths were assessed in a baseline survey in 2005, monitored during the trial in 2008-2011 and followed up by a survey in 2014. Time series analyses were performed on monthly neonatal mortality data.

    RESULTS: There were 30 187 live births and 480 neonatal deaths. The intervention reduced the neonatal mortality from 19.1 to 11.6 per 1000 live births. The reduction was sustained 3 years after the trial. The control areas reached a similar level at the time of follow-up. Time series decomposition analysis revealed a downward trend in the intervention areas during the trial that was not found in the control areas. Neonatal mortality peaked in the hot and wet summers.

    CONCLUSIONS: A community engagement intervention resulted in a lower neonatal mortality rate that was sustained but not further reduced after the end of the trial. When decomposing time series of neonatal mortality, a clear downward trend was demonstrated in intervention but not in control areas.

    TRIAL REGISTRATION NUMBER: ISRCTN44599712, Post-results.

  • Hitimana, Regis
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Epidemiologi och global hälsa. School of Public Health, College of Medicine and Health Sciences, University of Rwanda, Kigali, Rwanda.
    Lindholm, Lars
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Epidemiologi och global hälsa.
    Krantz, Gunilla
    Nzayirambaho, Manasse
    Condo, Jeanine
    Sengoma, Jean Paul Semasaka
    Umeå universitet, Medicinska fakulteten, Institutionen för klinisk vetenskap. School of Public Health, College of Medicine and Health Sciences, University of Rwanda, Kigali, Rwanda.
    Pulkki-Brännström, Anni-Maria
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Epidemiologi och global hälsa.
    Health-related quality of life determinants among Rwandan women after delivery: does antenatal care utilization matter? A cross-sectional study2018Inngår i: Journal of Health, Population and Nutrition, ISSN 1606-0997, E-ISSN 2072-1315, Vol. 37, artikkel-id 12Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background: Despite the widespread use of antenatal care (ANC), its effectiveness in low-resource settings remains unclear. In this study, self-reported health-related quality of life (HRQoL) was used as an alternative to other maternal health measures previously used to measure the effectiveness of antenatal care. The main objective of this study was to determine whether adequate antenatal care utilization is positively associated with women's HRQoL. Furthermore, the associations between the HRQoL during the first year (113 months) after delivery and socio-economic and demographic factors were explored in Rwanda.

    Methods: In 2014, we performed a cross-sectional population-based survey involving 922 women who gave birth 1-13 months prior to the data collection. The study population was randomly selected from two provinces in Rwanda, and a structured questionnaire was used. HRQoL was measured using the EQ-5D-3L and a visual analogue scale (VAS). The average HRQoL scores were computed by demographic and socio-economic characteristics. The effect of adequate antenatal care utilization on HRQoL was tested by performing two multivariable linear regression models with the EQ-5D and EQ-VAS scores as the outcomes and ANC utilization and socio-economic and demographic variables as the predictors.

    Results: Adequate ANC utilization affected women's HRQoL when the outcome was measured using the EQ-VAS. Social support and living in a wealthy household were associated with a better HRQoL using both the EQ-VAS and EQ-5D. Cohabitating, and single/unmarried women exhibited significantly lower HRQoL scores than did married women in the EQ-VAS model, and women living in urban areas exhibited lower HRQoL scores than women living in rural areas in the ED-5D model. The effect of education on HRQoL was statistically significant using the EQ-VAS but was inconsistent across the educational categories. The women's age and the age of their last child were not associated with their HRQoL.

    Conclusions: ANC attendance of at least four visits should be further promoted and used in low-income settings. Strategies to improve families' socio-economic conditions and promote social networks among women, particularly women at the reproductive age, are needed.

  • Disputas: 2018-06-15 08:00 Domteatern, Visualiseringscenter C, Kungsgatan 54, Norrköping
    Bock, Alexander
    Linköpings universitet, Tekniska fakulteten. Linköpings universitet, Institutionen för teknik och naturvetenskap, Medie- och Informationsteknik.
    Tailoring visualization applications for tasks and users2018Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Exponential increases in available computational resources over the recent decades have fueled an information explosion in almost every scientific field. This has led to a societal change shifting from an information-poor research environment to an over-abundance of information. As many of these cases involve too much information to directly comprehend, visualization proves to be an effective tool to gain insight into these large datasets. While visualization has been used since the beginning of mankind, its importance is only increasing as the exponential information growth widens the difference between the amount of gathered data and the relatively constant human ability to ingest information. Visualization, as a methodology and tool of transforming complex data into an intuitive visual representation can leverage the combined computational resources and the human cognitive capabilities in order to mitigate this growing discrepancy.

    A large portion of visualization research is, directly or indirectly, targets users in an application domain, such as medicine, biology, physics, or others. Applied research is aimed at the creation of visualization applications or systems that solve a specific problem within the domain. Combining prior research and applying it to a concrete problem enables the possibility to compare and determine the usability and usefulness of existing visualization techniques. These applications can only be effective when the domain experts are closely involved in the design process, leading to an iterative workflow that informs its form and function. These visualization solutions can be separated into three categories: Exploration, in which users perform an initial study of data, Analysis, in which an established technique is repeatedly applied to a large number of datasets, and Communication in which findings are published to a wider public audience.

    This thesis presents five examples of application development in finite element modeling, medicine, urban search & rescue, and astronomy and astrophysics. For the finite element modeling, an exploration tool for simulations of stress tensors in a human heart uses a compression method to achieve interactive frame rates. In the medical domain, an analysis system aimed at guiding surgeons during Deep Brain Stimulation interventions fuses multiple modalities in order to improve their outcome. A second analysis application is targeted at the Urban Search & Rescue community supporting the extraction of injured victims and enabling a more sophisticated decision making strategy. For the astronomical domain, first, an exploration application enables the analysis of time-varying volumetric plasma simulations to improving these simulations and thus better predict space weather. A final system focusses on combining all three categories into a single application that enables the same tools to be used for Exploration, Analysis, and Communication, thus requiring the handling of large coordinate systems, and high-fidelity rendering of planetary surfaces and spacecraft operations.

  • Paixao, Enny S.
    et al.
    Leong, Wei-Yee
    Rodrigues, Laura C.
    Wilder-Smith, Annelies
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin.
    Asymptomatic Prenatal Zika Virus Infection and Congenital Zika Syndrome2018Inngår i: Open Forum Infectious Diseases, ISSN 2328-8957, Vol. 5, nr 4Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    To investigate to what extent asymptomatic vs symptomatic prenatal Zika virus infections contribute to birth defects, we identified 3 prospective and 8 retrospective studies. The ratio varied greatly in the retrospective studies, most likely due to recruitment and recall bias. The prospective studies revealed a ratio of 1: 1 for asymptomatic vs symptomatic maternal Zika infections resulting in adverse fetal outcomes.

  • Disputas: 2018-06-13 13:00 Nordenskiöldsalen, Geovetenskapens hus, Stockholm
    Dehdari, Sirus Håfström
    Stockholms universitet, Samhällsvetenskapliga fakulteten, Nationalekonomiska institutionen.
    Radical Right, Identity, and Retaliation2018Doktoravhandling, monografi (Annet vitenskapelig)
    Abstract [en]

    Economic Distress and Support for Far-right Parties – Evidence from Sweden. This paper studies the effects of economic distress on support for far-right parties. Using Swedish election data, I show that layoff notifications among low-skilled native-born workers account for 31 percent of the increased vote share for the Swedish far-right party the Sweden Democrats. The effect of layoff notifications on support for the Sweden Democrats is larger in areas with a high share of low-skilled immigrants, and in areas with a low share of high-skilled immigrants. These findings are in line with theories suggesting that voters attribute their impaired economic status to immigration, due to labor market concerns. Furthermore, I find no effects on voting for other anti-EU and anti-globalization parties, challenging the notion that economic distress increases anti-globalization sentiment. Using detailed survey data, I present suggestive evidence of how increased salience of political issues related to immigration channels unemployment risk into support for far-right parties.

    The Origins of Common Identity: Division, Homogenization Policies and Identity Formation in Alsace-Lorraine. We exploit the quasi-exogenous division of the French regions Alsace and Lorraine after the Franco-Prussian War in 1870 due to disagreements in the German leadership to provide evidence of group identity formation within historically homogeneous regions. People in the treated area, which was exposed to repressive homogenization policies aimed to suppress group identity, express a stronger regional identity and support more regional autonomy today. Using a regression discontinuity design at the municipal level, we find that support for two crucial referenda, which would have increased regional autonomy, subscription rates to regional newspapers, and regionalist party votes are significantly higher in the treated area. The results are robust across different specifications and bandwidths, and not driven by language differences, large agglomerations or distance to foreign countries. The differences in regional identity are strongest for the first two age cohorts after World War II and become weaker for later generations.

    Gender Differences in Revenge and Strategic play: A Natural Experiment. This paper provides new evidence of gender differences in retaliatory behavior. Using game show data from a natural setting where stakes are high, we ask whether men are more likely to retaliate following an attack and whether the gender of the target matters for this decision. The behavior studied in this paper is the decision of whom to send the question to in a quiz show setting. We observe a 23 percent gender gap in the propensity to retaliate: women are less likely to seek revenge. The gender of the target matters for women but not for men, with women being more likely to retaliate against men than women. In addition, we show that retaliation is a successful way to avert future attacks in the short term. This is especially true for women, yet we find that women seek less revenge than men.

  • Disputas: 2018-06-15 10:00 K2, Stockholm
    Zhang, Yafan
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Elkraftteknik. RISE Acreo AB.
    Multiphysics Characterization of SiC Power Modules2018Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    This thesis proposes several novel silicon carbide power module design concepts. The goal has been to address the problems with the present designs. The electrical, thermal, and thermomechanical performances of the demonstrators have been evaluated along with presentations of methodologies of experimental and numerical characterizations.

    Compact high-temperature power modules with adequate cooling systems are attractive to automotive applications. Therefore, a novel thermal design of a double-sided liquid/air cooled silicon carbide power module (1200 V, 200 A) has been proposed. The concept integrates a dc-link capacitor, a gate driver board, and finned cooling channels. The cooling concept has been evaluated for three application scenarios based on a validated computational fluid dynamics model. Moreover, a simulation methodology has been developed to quantify the effect of different materials and thicknesses of the cold plates on the temperature of the silicon carbide power dies.

    For medium- and high-power applications, contemporary research concludes that the reliability of the existing packaging technology needs to be improved. Therefore, this work proposes a novel press-pack silicon carbide power module concept. The concept enables bondless package and allows for an order of magnitude higher clamping force on the heatsinks than what can be applied on the dies. First, experimental and numerical methodologies for thermomechanical performance characterization of a press-pack structure have been investigated. By using digital image correlation technique, the deformation of each stacked material layer has been obtained. The developed experiment has led to an analytical estimation of friction coefficients on the contact interfaces. The co-influence of the design parameters on the thermomechanical performance of the press-pack structure has been analyzed through a parametric study based on a finite element model. Second, the novel double press-pack silicon carbide power module concept has been evaluated in a demonstrator in terms of parasitic inductance, thermal resistance, and thermomechanical stress.

    Furthermore, many of the power module designs only stay at the stage of proof-of-concept due to the cost of retooling of the manufacturing facility. Embedded power modules which employ advanced printed circuit board processing and die embedding technologies, enable a solution with possibility of low cost and mass production. Therefore, a novel design concept of a three-phase embedded power module (1200 V, 20 A) has been proposed. Simulation-driven design development has been implemented and lead to a fabricated demonstrator. The electromagnetic, thermal, and thermomechanical performances of the concept have been evaluated by simulations and compared to a commercially available power module.

  • Disputas: 2018-06-15 10:15 F2, Stockholm
    Canton, Jacopo
    KTH, Skolan för teknikvetenskap (SCI), Mekanik.
    Of Pipes and Bends2018Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    This work is concerned with the transition to turbulence of the flow in bent pipes, but it also includes an analysis of large-scale turbulent structures and their use for flow control.

    The flow in a toroidal pipe is selected as it represents the common asymptotic limit between spatially developing and helical pipes. The study starts with a characterisation of the laminar flow as a function of curvature and the Reynolds number Re, since the so-called Dean number is found to be of little use except for infinitesimally low curvatures. It is found that the flow is modally unstable and undergoes a Hopf bifurcation for any curvature greater than zero. The bifurcation is studied in detail, and an effort to connect this modal instability with the linearly stable straight pipe is also presented.

    This flow is not only modally unstable, but undergoes subcritical transition at low curvatures. This scenario is found to bear similarities to straight pipes, but also fundamental differences such as weaker turbulent structures and the apparent absence of puff splitting. Toroidal pipe flow is peculiar, in that it is one of the few fluid flows presenting both sub- and supercritical transition to turbulence; the critical point where the two scenarios meet is therefore of utmost interest. It is found that a bifurcation cascade and featureless turbulence actually coexist for a range of curvature and Re, and the attractors of the respective structures have a small but finite basin of attraction.

    In 90◦ bent pipes at higher Re large-scale flow structures cause an oscilla- tory motion known as swirl-switching. Three-dimensional proper orthogonal decomposition is used to determine the cause of this phenomenon: a wave-like structure which is generated in the bent section, and is possibly a remnant of a low-Re instability.

    The final part of the thesis has a different objective: to reduce the turbulent frictional drag on the walls of a channel by employing a control strategy independent of Re-dependent turbulent scales, initially proposed by Schoppa & Hussain [Phys. Fluids 10:1049–1051 (1998)]. Results show that the original method only gives rise to transient drag reduction while a revised version is capable of sustained drag reduction of up to 18%. However, the effectiveness of this control decreases rapidly as the Reynolds number is increased, and the only possibility for high-Re applications is to use impractically small actuators.

  • Disputas: 2018-06-13 10:00 Sal C Elctrum, Stockholm
    Uždavinys, Tomas
    KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik.
    Optical properties of GaN and InGaN studied by time- and spatially-resolved spectroscopy2018Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The past decade has seen rapid expansion in the use of group III-nitride based devices. White InGaN LEDs are substituting incandescent light bulbs, space satellite industry adopting ion-radiation-resistant GaN transistors, and AlGaN deep UV LEDs are increasingly being used for water disinfection and air purification. Despite this success, performance and efficiency of many devices is still far from optimal with many fundamental material properties still disputed and technological issues not solved. For example, the energy difference between the lowest conduction band valleys in the case of GaN is still being debated, and an efficient white light source of monolithic three-color LED has still not been achieved, due to the poor quantum efficiency of green-emitting quantum wells.

    In view of these material challenges, this thesis was dedicated to studies of GaN, InGaN and their quantum wells with the help of time- and spatially- resolved spectroscopy and numerical modeling. This work provides new insights on both the fundamental and the growth-induced properties. Specifically, the energy difference between the lowest conduction band valleys in GaN, a key parameter for electronic devices, has been experimentally evaluated. In addition, electron scattering rates and satellite valley’s effective mass have been estimated by modeling pump-probe transients with rate equations. A study on Fe doped GaN has revealed that, depending on the device operation rate, different Fe+3 states should be considered when modelling GaN:Fe-based optoelectronic devices. Moreover, electron and hole capture coefficients and their temperature dependence have been determined. It has also been demonstrated that the random alloy model could only be used to describe emission and absorption linewidths in the InGaN alloy for a very low-In-content samples. Indium incorporation into the alloy has been found to be affected by the geometry of monolayer step edges that are formed during growth. Time-resolved scanning near-field photoluminescence spectroscopy studies on non-polar and semi-polar InGaN/GaN quantum wells have demonstrated that the common assumption of a spatially uniform radiative recombination rate is not always correct. Finally, it has been found that for a moderate to high-In-content QW the photoluminescence linewidth is defined primarily by variations of alloy composition and not well width fluctuations.

  • Prince, Solene
    Mittuniversitetet, Fakulteten för humanvetenskap, Avdelningen för turismvetenskap och geografi.
    Science and Culture in the Kerguelen Islands: a relational approach to the spatial formation of a subantarctic archipelago2018Inngår i: Island Studies Journal, ISSN 1715-2593, E-ISSN 1715-2593Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The Kerguelen Islands are devoid of a permanent population, but are nonetheless interlinked to past and current human activities that have shaped their subantarctic landscape. In the past decades, the archipelago has become a French outpost for scientific research where scientists, support staff, research assistants, and travelers assemble during temporary missions. In this article, I present the spatial formation of islands as relational in order to explore how the material and the cultural converge to make the Kerguelen Islands a place of both mundane practice and global interconnection. These spatialities intertwine the features of the landscape with pre-departure preparations, animal encounters, scientific rigour, daily routines, and past human activities. I advance these narratives by analyzing 18 blogs of French sojourners who have spent extensive time on the Kerguelen Islands. I ultimately give islands without a permanent population a character unlike that of isolation and contemplation as is usually attributed to cold-water islands of the (sub) polar seas.

  • Disputas: 2018-05-31 14:00 FB42, Stockholm
    Mikhalev, Victor
    KTH, Skolan för teknikvetenskap (SCI), Fysik, Partikel- och astropartikelfysik.
    Measurements of hard X-ray polarization from the Crab and Cygnus X-12018Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Polarimetry provides insights into the emission mechanisms of astrophysical sources by elucidating their magnetic field and geometry. Hard X-rays are produced in \mbox{regions} with strong magnetic fields or strong gravitational effects, which makes them a probe of extreme environments. This thesis describes the design, \mbox{calibration} and data analysis from the balloon-borne hard X-ray polarimeters the PoGOLite Pathfinder and its upgrade PoGO+. These instruments have measured the polari-zation from the Crab nebula and pulsar, and of the black hole binary Cygnus X-1.

    Paper I explores to what extent the statistical uncertainties on the polarization parameters are non-Gaussian when the number of photons is low, as tends to be the case for balloon-borne instruments.With this in mind, a Bayesian method is used for data analysis in the subsequent papers. Paper II describes the measurement of the polarization of the Crab system in the 20-120 keV energy range conducted by the PoGOLite Pathfinder. Although the result is modest in its statistical significance it paves the way for the design of the upgraded instrument PoGO+.

    The PoGO+ mission was conceived to remedy the shortcomings of the PoGOLite Pathfinder design and observation strategy, as well as the pre-flight calibration, which the focus of Paper III. Significant improvements are made to the detector response model, optimization of data acquisition thresholds, online veto system and to the general calibration procedure. When combined with interspersed target and background measurements, systematic uncertainties are significantly smaller for PoGO+ than for the PoGOLite Pathfinder.

    The main scientific results are presented in Papers IV and V for the Crab (20-160 keV) and Cygnus X-1 (20-180 keV), respectively. For the Crab, PoGO+ does not support a rapid increase in the polarization fraction claimed previously. Additionally, the hard X-ray emission must be produced close to the pulsar and possibly in the fine structures of the nebula. This is in agreement with X-ray images from other instruments. For Cygnus X-1, the polarization measurements constrain the geometry by rejecting the model where the hard X-rays are produced in a compact corona close to the black hole and support the extended corona model.

    The thesis demonstrates how balloon-borne instruments can be improved over the course of several campaigns and can contribute to the testing of detector design, development of analysis methods and provide new scientific results for bright X-ray sources.

  • Disputas: 2018-06-11 10:15 Hörsal E, Umeå
    Larsson, Magnus
    Umeå universitet, Samhällsvetenskapliga fakulteten, Sociologiska institutionen.
    National environmental evaluation systems: guiding towards sustainability?2018Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Background: Dealing with environmental threats is one of the largest, if not the largest, challenge contemporary societies face. One way to better deal with this challenge would be to produce knowledge that can be used to improve environmental work and environmental policy and thus ultimately contribute to sustainable development. National environmental evaluations, which this thesis explores, could potentially fill this function because they are supposed to generate applicable and useful knowledge for improving environmental policy and practice for a sustainable transition. However, what different environmental actors view as useful knowledge varies, and needs to be empirically investigated. Against this background, the aim of this thesis is to investigate whether, and how, national environmental evaluation systems contribute to key actors’ environmental work and sustainable development. The thesis explores two national environmental evaluation systems in Sweden.

    Method: A mixed methods approach is applied that combines three methods. Firstly, a narrative synthesis is developed and applied to compile a list of sustainable development effects from national environmental evaluations. Secondly, a critical program theory is used to investigate the evaluation system’s underlying logic and to assess the likelihood of it achieving its intended effects. Thirdly, a directed content analysis is used to explore the usability and use of environmental evaluations and evaluation systems. The methods are applied to various documents, interviews with key actors, and observations at two environmental seminars.

    Results: The results show that, to contribute to sustainable development in the context of evaluation systems and network governance, environmental evaluations need to be of sufficient quality and meet different stakeholders’ knowledge needs. However, only some evaluations meet this demand. The main value of national environmental evaluations and evaluation systems is that they reinforce the national objectives, provide a recurrent report on achievement of objectives, and push actors to take responsibility to improve their environmental work.

  • Camino-Serrano, Marta
    et al.
    Guenet, Bertrand
    Luyssaert, Sebastiaan
    Ciais, Philippe
    Bastrikov, Vladislav
    De Vos, Bruno
    Gielen, Bert
    Gleixner, Gerd
    Jornet-Puig, Albert
    Kaiser, Klaus
    Kothawala, Dolly
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Limnologi.
    Lauerwald, Ronny
    Peñuelas, Josep
    Schrumpf, Marion
    Vicca, Sara
    Vuichard, Nicolas
    Walmsley, David
    Janssens, Ivan A.
    ORCHIDEE-SOM: Modeling soil organic carbon (SOC) and dissolved organic carbon (DOC) dynamics along vertical soil profiles in Europe2018Inngår i: Geoscientific Model Development, ISSN 1991-959X, E-ISSN 1991-9603, Vol. 11, nr 3, s. 937-957Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Current Land Surface Models (LSMs) typically represent soils in a very simplistic way, assuming soil organic carbon (SOC) as a bulk, thus impeding a correct representation of deep soil carbon dynamics. Moreover, LSMs generally neglect the production and export of dissolved organic carbon (DOC) from soils to rivers, leading to overestimations of the potential carbon sequestration on land. These common oversimplified processing of SOC in LSMs is partly responsible for the large uncertainty in the predictions of the soil carbon response to climate change. In this study, we present a new soil carbon module called ORCHIDEE-SOM, embedded within the land surface model ORCHIDEE, which is able to reproduce the DOC and SOC dynamics in a vertically discretized soil to two meters. The model includes processes of biological production and consumption of SOC and DOC, DOC adsorption on- and desorption from soil minerals, diffusion of SOC and DOC and DOC transport with water through and out of the soils to rivers. We evaluated ORCHIDEE-SOM against observations of DOC concentrations and SOC stocks from four European sites with different vegetation covers: a coniferous forest, a deciduous forest, a grassland and a cropland. The model was able to reproduce the SOC stocks along their vertical profiles at the four sites and the DOC concentrations within the range of measurements, with the exception of the DOC concentrations in the upper soil horizon at the coniferous forest. However, the model was not able to fully capture the temporal dynamics of DOC concentrations. Further model improvements should focus on a plant- and depth- dependent parameterization of the new input model parameters, such as the decomposition times of DOC and the microbial carbon use efficiency. We suggest that this new soil module, when parameterized for global simulations, will improve the representation of the global carbon cycle in LSMs, thus helping to constrain the predictions of the future SOC response to global warming.\textless/p\textgreater

  • Krizsan, Sophie J
    et al.
    Swedish University of Agricultural Sciences, Umeå, Sweden.
    Mateos-Rivera, Alejandro
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Limnologi.
    Bertilsson, Stefan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Limnologi.
    Felton, Annika
    Swedish University of Agricultural Sciences, Alnarp, Sweden.
    Anttila, Anne
    Helsinki University, Helsinki, Finland.
    Ramin, Mohammad
    Swedish University of Agricultural Sciences, Umeå, Sweden.
    Vaga, Merko
    Swedish University of Agricultural Sciences, Umeå, Sweden.
    Gidlund, Helena
    Swedish University of Agricultural Sciences, Umeå, Sweden.
    Huhtanen, Pekka
    Swedish University of Agricultural Sciences, Umeå, Sweden.
    An in vitro evaluation of browser and grazer fermentation efficiency and microbiota using European moose spring and summer foods2018Inngår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 8, s. 4183-4196Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Evolutionary morphological and physiological differences between browsers and grazers contribute to species- specific digestion efficiency of food resources. Rumen microbial community structure of browsers is supposedly adapted to characteristic nutrient composition of the diet source. If this assumption is correct, domesticated ruminants, or grazers, are poor model animals for assessing the nutritional value of food consumed by browsing game species. In this study, typical spring and summer foods of the European moose (Alces alces) were combined with rumen fluid collected from both dairy cows (Bos taurus) and from moose, with the aim of comparing fer- mentation efficiency and microbial community composition. The nutritional value of the food resources was characterized by chemical analysis and advanced in vitro measurements. The study also addressed whether or not feed evaluation based on in vitro techniques with cattle rumen fluid as inoculum could be a practical alternative when evaluating the nutritional value of plants consumed by wild browsers. Our re- sults suggest that the fermentation characteristics of moose spring and summer food are partly host- specific and related to the contribution of the bacterial phyla Firmicutes and Bacteriodetes to the rumen microbial community. Host- specific adaptations of the ruminal microbial community structure could be explained from the evolutionary adaptations related to feeding habitats and morphophysiological differences be- tween browsers and grazers. However, the observed overall differences in microbial community structure could not be related to ruminal digestion parameters measured in vitro. The in vitro evaluation of digestion efficiency reveals that equal amounts of methane were produced across all feed samples regardless of whether the ruminal fluid was from moose or dairy cow. The results of this study suggested that the nutri- tional value of browsers’ spring and summer food can be predicted using rumen fluid from domesticated grazers as inoculum in in vitro assessments of extent of digestion when excluding samples of the white water lily root, but not of fermentation characteristics as indicated by the proportions of individual fermentation fatty acids to the total of volatile fatty acids.

  • Jacobsen, Carsten Suhr
    et al.
    Nielsen, Tue Kjærgaard
    Vester, Jan Kjølhede
    Stougaard, Peter
    Nielsen, Jeppe Lund
    Voriskova, Jana
    Winding, Anne
    Baldrian, Petr
    Liu, Binbin
    Frostegård, Åsa
    Pedersen, Dorthe
    Tveit, Alexander Tøsdal
    Svenning, Mette Marianne
    Tebbe, Christoph C.
    Øvreås, Lise
    Jakobsen, Pia Bach
    Blazewicz, Steven J.
    Hubablek, Valerie
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Limnologi. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Bertilsson, Stefan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Limnologi. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Hansen, Lars Hestbjerg
    Cary, S. Craig
    Holben, William E.
    Ekelund, Flemming
    Bælum, Jacob
    Inter-laboratory testing of the effect of DNA blocking reagent G2 on DNA extraction from low-biomass clay samples2018Inngår i: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 8, artikkel-id 5711Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Here we show that a commercial blocking reagent (G2) based on modified eukaryotic DNA significantly improved DNA extraction efficiency. We subjected G2 to an inter-laboratory testing, where DNA was extracted from the same clay subsoil using the same batch of kits. The inter-laboratory extraction campaign revealed large variation among the participating laboratories, but the reagent increased the number of PCR-amplified16S rRNA genes recovered from biomass naturally present in the soils by one log unit. An extensive sequencing approach demonstrated that the blocking reagent was free of contaminating DNA, and may therefore also be used in metagenomics studies that require direct sequencing.

  • Garmy, Pernilla
    Högskolan Kristianstad, Forskningsmiljön Children's and Young People's Health in Social Context (CYPHiSCO). Högskolan Kristianstad, Forskningsplattformen för Hälsa i samverkan. Högskolan Kristianstad, Fakulteten för hälsovetenskap, Avdelningen för sjuksköterskeutbildningarna och integrerad hälsovetenskap.
    School nurses' Experiences in working with students with mental health problems2017Konferansepaper (Fagfellevurdert)
  • Young, Joanna C.
    et al.
    Univ Alaska, Geophys Inst, Fairbanks, AK 99701 USA..
    Arendt, Anthony
    Univ Alaska, Geophys Inst, Fairbanks, AK 99701 USA.;Univ Washington, Polar Sci Ctr, Appl Phys Lab, Seattle, WA 98195 USA..
    Hock, Regine
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Luft-, vatten och landskapslära. Univ Alaska, Geophys Inst, Fairbanks, AK 99701 USA..
    Pettit, Erin
    Univ Alaska Fairbanks, Dept Geosci, Fairbanks, AK USA..
    The challenge of monitoring glaciers with extreme altitudinal range: mass-balance reconstruction for Kahiltna Glacier, Alaska2018Inngår i: Journal of Glaciology, ISSN 0022-1430, E-ISSN 1727-5652, Vol. 64, nr 243, s. 75-88Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Glaciers spanning large altitudinal ranges often experience different climatic regimes with elevation, creating challenges in acquiring mass-balance and climate observations that represent the entire glacier. We use mixed methods to reconstruct the 1991-2014 mass balance of the Kahiltna Glacier in Alaska, a large (503 km(2)) glacier with one of the greatest elevation ranges globally (264-6108m a. s.l.). We calibrate an enhanced temperature index model to glacier-wide mass balances from repeat laser altimetry and point observations, finding a mean net mass-balance rate of -0.74 mw.e. a(-1)(+/-sigma = 0.04, std dev. of the best-performing model simulations). Results are validated against mass changes from NASA's Gravity Recovery and Climate Experiment (GRACE) satellites, a novel approach at the individual glacier scale. Correlation is strong between the detrended model-and GRACE-derived mass change time series (R-2 = 0.58 and p << 0.001), and between summer (R-2 = 0.69 and p = 0.003) and annual (R-2 = 0.63 and p = 0.006) balances, lending greater confidence to our modeling results. We find poor correlation, however, between modeled glacier-wide balances and recent single-stake monitoring. Finally, we make recommendations for monitoring glaciers with extreme altitudinal ranges, including characterizing precipitation via snow radar profiling.

  • Liang, Feiyan
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Molekylär biomimetik.
    Englund, Elias
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Molekylär biomimetik.
    Lindberg, Pia
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Molekylär biomimetik.
    Lindblad, Peter
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Molekylär biomimetik.
    Engineered cyanobacteria with enhanced growth show increased ethanol production and higher biofuel to biomass ratio2018Inngår i: Metabolic engineering, ISSN 1096-7176, E-ISSN 1096-7184, Vol. 46, s. 51-59Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The Calvin-Benson-Bassham (CBB) cycle is the main pathway to fix atmospheric CO2 and store energy in carbon bonds, forming the precursors of most primary and secondary metabolites necessary for life. Speeding up the CBB cycle theoretically has positive effects on the subsequent growth and/or the end metabolite(s) production. Four CBB cycle enzymes, ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO), fructose-1,6/sedoheptulose-1,7-bisphosphatase (FBP/SBPase), transketolase (TK) and aldolase (FBA) were selected to be co-overexpressed with the ethanol synthesis enzymes pyruvate decarboxylase (PDC) and alcohol dehydrogenase (ADH) in the cyanobacterium Synechocystis PCC 6803. An inducible promoter, PnrsB, was used to drive PDC and ADH expression. When PnrsB was induced and cells were cultivated at 65 µmol photons m−2 s−1, the RuBisCO-, FBP/SBPase-, TK-, and FBA-expressing strains produced 55%, 67%, 37% and 69% more ethanol and 7.7%, 15.1%, 8.8% and 10.1% more total biomass (the sum of dry cell weight and ethanol), respectively, compared to the strain only expressing the ethanol biosynthesis pathway. The ethanol to total biomass ratio was also increased in CBB cycle enzymes overexpressing strains. This study experimentally demonstrates that using the cells with enhanced carbon fixation, when the product synthesis pathway is not the main bottleneck, can significantly increase the generation of a product (exemplified with ethanol), which acts as a carbon sink.

  • Gabrysch, Katja
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Matematiska institutionen, Analys och sannolikhetsteori.
    Thörnblad, Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Matematiska institutionen, Analys och sannolikhetsteori.
    The greedy walk on an inhomogeneous Poisson process2018Inngår i: Electronic Communications in Probability, ISSN 1083-589X, E-ISSN 1083-589X, Vol. 23, artikkel-id 14Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The greedy walk is a deterministic walk that always moves from its current position to the nearest not yet visited point. In this paper we consider the greedy walk on an inhomogeneous Poisson point process on the real line. We prove that the property of visiting all points of the point process satisfies a 0-1 law and determine explicit sufficient and necessary conditions on the mean measure of the point process for this to happen. Moreover, we provide precise results on threshold functions for the property of visiting all points.

  • Kindbom, Karin
    et al.
    Utförare miljöövervakning, Forskningsinstitut, IVL Svenska Miljöinstitutet AB.
    Lidén, Maria
    SCB.
    Adolfsson, Rolf
    SCB.
    Tillämpning av Good Practice Guidance Förstudie2003Rapport (Annet vitenskapelig)
  • Dyrssen, Hannah
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Matematiska institutionen.
    Ekström, Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Matematiska institutionen, Analys och sannolikhetsteori.
    Sequential testing of a Wiener process with costly observations2018Inngår i: Sequential Analysis, ISSN 0747-4946, E-ISSN 1532-4176, Vol. 37, nr 1, s. 47-58Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We consider the sequential testing of two simple hypotheses for the drift of a Brownian motion when each observation of the underlying process is associated with a positive cost. In this setting where continuous monitoring of the underlying process is not feasible, the question is not only whether to stop or to continue at a given observation time but also, if continuing, how to distribute the next observation time. Adopting a Bayesian methodology, we show that the value function can be characterized as the unique fixed point of an associated operator and that it can be constructed using an iterative scheme. Moreover, the optimal sequential distribution of observation times can be described in terms of the fixed point.

  • Berglind, Daniel
    et al.
    Nyberg, Gisela
    Willmer, Mikaela
    Persson, Margareta
    Umeå universitet, Medicinska fakulteten, Institutionen för omvårdnad.
    Wells, Michael
    Forsell, Yvonne
    An eHealth program versus a standard care supervised health program and associated health outcomes in individuals with mobility disability: study protocol for a randomized controlled trial2018Inngår i: Trials, ISSN 1745-6215, E-ISSN 1745-6215, Vol. 19, artikkel-id 258Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background: Young adults with mobility disability (MD) are less likely to engage in regular physical activity (PA) compared with their able-bodied peers and inactive adults with a MD are more likely to report one or more chronic diseases compared to those who are physically active. Despite the vast amount of research published in the field of PA interventions over the past decades, little attention has been focused on interventions aiming to increase PA among individuals with MD. Thus, we propose to compare the effects of an eHealth program compared to a usual care supervised health program on levels of PA and other health behaviors. 

    Methods: The current intervention will use a randomized controlled trial (RCT) design with two treatment groups (an eHealth program and a usual care supervised health program) in young adults with newly acquired MD. In total, 110 young adults (aged 18-40 years) with a MD, acquired within the past 3 years, will be recruited to participate in a 12-week intervention. The primary study outcome is accelerometer-measured time spent in moderate to vigorous PA. Secondary outcomes includes health-related quality of life, depression, stress, fitness, body composition, diet, musculoskeletal pain, motivation to exercise and work ability.

    Discussion: There is a lack of RCTs investigating effective ways to increase levels of PA in young adults with MD. Increased levels of PA among this physically inactive population have the potential to substantially improve health-related outcomes, possibly more so than in the general population. The trial will put strong emphasis on optimizing exercise adherence and investigating feasibility in the two treatment programs. The Ethical Review Board (EPN) at Karolinska Institutet has approved the study (2017/1206-31/1).

  • Moodie, John
    et al.
    Nordiska ministerrådet, Nordregio.
    Teräs, Jukka
    Nordiska ministerrådet, Nordregio.
    Randall, Linda
    Nordiska ministerrådet, Nordregio.
    Building Effective Transnational Partnerships: The Case of Smart Lighting2018Annet (Annet (populærvitenskap, debatt, mm))
    Abstract [en]

    This policy brief examines the requirements for building effective transnational partnerships in different policy fields, based on the lessons learned from the recent Lighting Metropolis project – a cross-border innovation venture between Denmark and Sweden that sought to develop smart lighting solutions in urban environments. The brief begins with an overview of this new technology area, before outlining the main opportunities and challenges in the implementation of smart lighting throughout Europe. This is followed by a review of the key findings from Lighting Metropolis, with a focus on assessing the experiences of transnational co-operation identified during the project. Finally, the concluding section outlines a number of recommendations for enhancing transnational collaboration. The policy brief has been prepared by Nordregio as part of the BSR Stars S3 project. It is based on a literature review and interviews conducted with partners involved in Lighting Metropolis.

  • Murina, Victoriia
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för molekylärbiologi (Medicinska fakulteten). Umeå universitet, Medicinska fakulteten, Molekylär Infektionsmedicin, Sverige (MIMS).
    Kasari, Marje
    Umeå universitet, Medicinska fakulteten, Institutionen för molekylärbiologi (Medicinska fakulteten).
    Hauryliuk, Vasili
    Umeå universitet, Medicinska fakulteten, Institutionen för molekylärbiologi (Medicinska fakulteten). Umeå universitet, Medicinska fakulteten, Molekylär Infektionsmedicin, Sverige (MIMS). University of Tartu, Institute of Technology, Tartu, Estonia.
    Atkinson, Gemma C.
    Umeå universitet, Medicinska fakulteten, Institutionen för molekylärbiologi (Medicinska fakulteten).
    Antibiotic resistance ABCF proteins reset the peptidyl transferase centre of the ribosome to counter translational arrest2018Inngår i: Nucleic Acids Research, ISSN 0305-1048, E-ISSN 1362-4962, Vol. 46, nr 7, s. 3753-3763Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Several ATPases in the ATP-binding cassette F (ABCF) family confer resistance to macrolides, lincosamides and streptogramins (MLS) antibiotics. MLS are structurally distinct classes, but inhibit a common target: the peptidyl transferase (PTC) active site of the ribosome. Antibiotic resistance (ARE) ABCFs have recently been shown to operate through direct ribosomal protection, but the mechanistic details of this resistance mechanism are lacking. Using a reconstituted translational system, we dissect the molecular mechanism of Staphylococcus haemolyticus VgaA(LC) and Enterococcus faecalis LsaA on the ribosome. We demonstrate that VgaA(LC) is an NTPase that operates as a molecular machine strictly requiring NTP hydrolysis (not just NTP binding) for antibiotic protection. Moreover, when bound to the ribosome in the NTP-bound form, hydrolytically inactive EQ(2) ABCF ARE mutants inhibit peptidyl transferase activity, suggesting a direct interaction between the ABCF ARE and the PTC. The likely structural candidate responsible for antibiotic displacement by wild type ABCF AREs, and PTC inhibition by the EQ(2) mutant, is the extended inter-ABC domain linker region. Deletion of the linker region renders wild type VgaA(LC) inactive in antibiotic protection and the EQ(2) mutant inactive in PTC inhibition.

  • Hjort, Mattias
    et al.
    Statens väg- och transportforskningsinstitut, Trafik och trafikant,TRAF, Förare och fordon, FOF.
    Niska, Anna
    Statens väg- och transportforskningsinstitut, Infrastruktur, INFRA, Drift och underhåll, DOU.
    Mätning av cykeldäcks friktionsegenskaper som underlag för simuleringsstudier2018Rapport (Annet vitenskapelig)
    Abstract [sv]

    I detta projekt har mätningar i VTI:s stationära däckprovningsanläggning utförts med ett cykeldäck på asfaltunderlag i syfte att ta fram slipkurvor som beskriver ett cykeldäcks friktionsegenskaper. Mätresultaten har sedan använts för att ta fram en däckparametrisering för simuleringsändamål. Följande däckparametrar har mätts: cornering stiffness, camber stiffness, brake slip stiffness och lateral relaxationslängd.

    Det testade däcket genererade en maximal friktionsnivå på ungefär 1,0 på asfalten. Typiska värden på däckparametrarna var: normerad cornering stiffness 0,3; normerad camber stiffness 0,01; normerad brake slip stiffness 250. Jämfört med de få tidigare publicerade mätningar på cykeldäck så är cornering stiffness generellt ca 50 procent högre än vad som hittills rapporterats. Värdena för camber stiffness motsvarar väl de värden som en studie av racingdäck uppvisat, men är 25–50 procent lägre än värden uppmätta på mer normala däck i en annan studie. För brake slip stiffness finns inga tidigare mätningar att jämföra med. Mätning av relaxationslängden påverkades tyvärr av problem med mätutrustningen och vi kunde inte bestämma denna med önskad noggrannhet. Från mätningarna uppskattar vi relaxationslängden till 200–300 mm för det testade däcket, vilket är en faktor 2–3 ggr större än vad som rapporterades i den enda studie som tidigare mätt relaxationslängd för cykeldäck.

  • Gould, Ernest
    et al.
    Aix Marseille Univ, EPV, IRD 190, INSERM 1207,EHESP, Marseille, France..
    Pettersson, John
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk biokemi och mikrobiologi. Norwegian Inst Publ Hlth, Domain Infect Control & Environm Hlth, Dept Infect Dis Epidemiol & Modelling Mol Biol, Oslo, Norway..
    Higgs, Stephen
    Kansas State Univ, Diagnost Med & Pathobiol, Manhattan, KS 66506 USA.;Kansas State Univ, KS Biosecur Res Inst, Manhattan, KS 66506 USA..
    Charrel, Remi
    Aix Marseille Univ, EPV, IRD 190, INSERM 1207,EHESP, Marseille, France.;Inst Hosp Univ Mediterranee Infect, APHM Publ Hosp Marseille, Marseille, France..
    de Lamballerie, Xavier
    Aix Marseille Univ, EPV, IRD 190, INSERM 1207,EHESP, Marseille, France.;Inst Hosp Univ Mediterranee Infect, APHM Publ Hosp Marseille, Marseille, France..
    Emerging arboviruses: Why today?2017Inngår i: ONE HEALTH, ISSN 2352-7714, Vol. 4, s. 1-13Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    The recent global (re)emergence of arthropod-borne viruses (arboviruses), such as chikungunya and Zika virus, was widely reported in the media as though it was a new phenomenon. This is not the case. Arboviruses and other human microbial pathogens have been (re)emerging for centuries. The major difference today is that arbovirus emergence and dispersion are more rapid and geographically extensive, largely due to intensive growth of global transportation systems, arthropod adaptation to increasing urbanisation, our failure to contain mosquito population density increases and land perturbation. Here we select examples of (re)emerging pathogenic arboviruses and explain the reasons for their emergence and different patterns of dispersal, focusing particularly on the mosquito vectors which are important determinants of arbovirus emergence. We also attempt to identify arboviruses likely to (re)emerge in the future.

  • Lønnebotn, Marianne
    et al.
    Svanes, Cecilie
    Igland, Jannicke
    Franklin, Karl A.
    Umeå universitet, Medicinska fakulteten, Institutionen för kirurgisk och perioperativ vetenskap.
    Accordini, Simone
    Benediktsdóttir, Bryndís
    Bentouhami, Hayat
    Blanco, José A. G.
    Bono, Roberto
    Corsico, Angelo
    Demoly, Pascal
    Dharmage, Shyamali
    Dorado Arenas, Sandra
    Garcia, Judith
    Heinrich, Joachim
    Holm, Mathias
    Janson, Christer
    Jarvis, Debbie
    Leynaert, Bénédicte
    Martinez-Moratalla, Jesús
    Nowak, Dennis
    Pin, Isabelle
    Raherison-Semjen, Chantal
    Sánchez-Ramos, Jose Luis
    Schlunssen, Vivi
    Skulstad, Svein Magne
    Dratva, Julia
    Real, Francisco Gómez
    Body silhouettes as a tool to reflect obesity in the past2018Inngår i: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 13, nr 4, artikkel-id e0195697Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Life course data on obesity may enrich the quality of epidemiologic studies analysing health consequences of obesity. However, achieving such data may require substantial resources. We investigated the use of body silhouettes in adults as a tool to reflect obesity in the past. We used large population-based samples to analyse to what extent self-reported body silhouettes correlated with the previously measured (9-23 years) body mass index (BMI) from both measured (European Community Respiratory Health Survey, N = 3 041) and selfreported (Respiratory Health In Northern Europe study, N = 3 410) height and weight. We calculated Spearman correlation between BMI and body silhouettes and ROC-curve analyses for identifying obesity (BMI >= 30) at ages 30 and 45 years. Spearman correlations between measured BMI age 30 (+/- 2y) or 45 (+/- 2y) and body silhouettes in women and men were between 0.62-0.66 and correlations for self-reported BMI were between 0.58-0.70. The area under the curve for identification of obesity at age 30 using body silhouettes vs previously measured BMI at age 30 (+/- 2y) was 0.92 (95% CI 0.87, 0.97) and 0.85 (95% CI 0.75, 0.95) in women and men, respectively; for previously self-reported BMI, 0.92 (95% CI 0.88, 0.95) and 0.90 (95% CI 0.85, 0.96). Our study suggests that body silhouettes are a useful epidemiological tool, enabling retrospective differentiation of obesity and non-obesity in adult women and men.

  • Disputas: 2018-06-07 10:00 F3, Stockholm
    Sundarapandian, Sembian
    KTH, Skolan för teknikvetenskap (SCI), Mekanik.
    Strong blast wave interaction with multiphase media2018Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The interaction of a blast wave propagating in air with different fluids like water column, aqueous foam and thermal/density inhomogeneity have been studied both experimentally and numerically. The blast waves were generated at atmospheric conditions in a newly constructed exploding wire facility. For fixed capacitance and wire size, the intensity of the shock front (measured typically at 200 mm from the wire explosion plane) was varied by controlling the charges stored in the capacitor and the size of the test section. Qualitative features of the interaction were captured using shadowgraph technique. Numerical simulations were performed to better analyze and understand the flow features observed in experiments. The main points across each fluid interactions are as follow:

    Water column: A new technique was implemented to create highly repeatable, properly shaped, large diameter water column. The impact of a blast wave with shock Mach number ranging from 1.75 to 2.4 on a 22 mm diameter water column resulted in a complex system of waves propagating inside the column. Due to the concave boundary of the downstream interface, the reflected expansion wave naturally focused at a point before travelling upstream resulting in the generation of large negative pressures leading to nucleation of cavitation bubbles. Through high speed photography, various aspects of the flow features were discussed qualitatively and quantitatively. With the aid of numerical simulation, the effect of size of water column and shock strength on the maximum attainable negative pressures in the absence of cavitation were quantified.

    Aqueous foam: The performance of various aqueous foam barrier configurations on the attenuation of externally generated blast wave peak pressure was examined. Here a blast wave with shock Mach number 4.8 was allowed to interact with an aqueous foam barrier of initial liquid fraction 0.1. The dominant process responsible for reduction of peak pressure was the `catching up' of the rarefaction wave with the wave front travelling in the foam barrier. Additional reduction was provided by the impedance mismatch factor at the foam-air interface which was further exploited to achieve greater reduction. A simple numerical model treating the foam by a pseudo-gas approach was used for re-constructing the experimental results.

    Density inhomogeneity: The unstable evolution of a 2D elongated, elliptically-shaped inhomogeneity embedded in ambient air and aligned both normal and at an angle to the incident plane blast wave of impact Mach number 2.15 was studied. The inhomogeneity was created on the basis of `Joule heating' wherein heat produced by a current carrying wire was used to heat its surrounding air. Two counter-rotating vortices primarily due to Richtmyer-Meshkov instability (RMI) and a train of vortices primarily due to Kelvin-Helmholtz instability (KHI) were observed for two different inclination angles. Similarly circulation, calculated from numerical simulation solving Navier-Stokes equation, was also found to vary from a linear to a quadratic function when the inhomogeneity was inclined.

  • Rodhe, Lena
    et al.
    RISE - Research Institutes of Sweden, Biovetenskap och material, Jordbruk och livsmedel.
    Alverbäck, Adam
    RISE - Research Institutes of Sweden, Biovetenskap och material, Jordbruk och livsmedel.
    Ascue, Johnny
    RISE - Research Institutes of Sweden, Biovetenskap och material, Jordbruk och livsmedel.
    Edström, Mats
    RISE - Research Institutes of Sweden, Biovetenskap och material, Jordbruk och livsmedel.
    Nordberg, Åke
    RISE - Research Institutes of Sweden, Biovetenskap och material, Jordbruk och livsmedel.
    Pizzul, Leticia
    RISE - Research Institutes of Sweden, Biovetenskap och material, Jordbruk och livsmedel.
    Tersmeden, Marianne
    RISE - Research Institutes of Sweden, Biovetenskap och material, Jordbruk och livsmedel.
    Åtgärder för att minimera växthusgasutsläpp från lager med rötad och orötad gödsel2018Rapport (Annet vitenskapelig)
    Abstract [sv]

    Kunskap om effektiva, funktionella och ekonomiska åtgärder krävs för att säkerställa små utsläpp av växthusgaser från lager med både orötad och rötad gödsel. I detta treåriga projekt har olika tänkbara åtgärder i flytgödsellager studerats genom mätning av växthusgaserna metan och lustgas under sommarförhållanden. Åtgärder som förlängd utrötningstid och surgörning av gödsel med svavelsyra, har utvärderats i RISE pilotskaleanläggning för lagring av flytgödsel. Åtgärder för att minska lustgasemissioner bildat i svämtäcke på gödselyta i ett fullskalelager har studerats på gårdsnivå. Kompletterande teoretiska beräkningar har utförts för att bedöma effekten av att täcka flytgödsellager samt laboratoriestudier av temperaturens påverkan på metangas-emissionerna.

    Grundläggande är att temperaturen har stor betydelse, vilket visades i laboratorieskalan. Vid ökad temperatur ökade metanproduktionen exponentiellt för rötad gödsel medan för orötad gödsel var ökningen betydligt mindre. De teoretiska värmebalansberäkningarna för lager med gödsel visade att beskuggning av gödselytan eller täckning av lager med vitt tak bör kunna reducera denna uppvärmning kraftigt på våren eftersom värmeinstrålningen från solljus till gödsellager kan förklarade största delen av gödselns uppvärmning.

    Studierna under första och sista året visade att metanemissionerna var signifikant större från gödseln när den var rötad än om den var orötad. Sammanlagda förlusterna av metan var 2,5 respektive fyra gånger så höga från den rötade gödseln under sommarlagringarna (ca fyra månader). Det betyder att det är speciellt viktigt att sätta in åtgärder vid lagring av rötad gödsel för att begränsa utsläppen av metan och därmed minska klimatpåverkan.

    En åtgärd för att få lägre metanemissioner från den rötade gödseln är att förlänga utrötningstiden, dvs. den hydrauliska uppehållstiden i rötkammaren. Studierna år 1 visar att vid en fördubblad uppehållstid, 48 dagar istället för 24 dagar, minskade metanemissionerna från lagret med 30 procent. På gårdar med rötningsanläggningar är ett gastätt tak med uppsamling av biogasen också en bra åtgärd för att effektivisera anläggningen och förhindra utsläpp av klimatgaser från lagret.

    Surgörning av flytgödsel med svavelsyra praktiseras främst i Danmark för att minska ammoniakavgången från flytgödsel, i stall, lager och vid spridning. Resultaten visar att det är en mycket effektiv metod för att minimera metangasemissionerna från lager med en reduktion med mer än 90 procent både för orötad och för rötad gödsel. Speciellt för gödselslag där det inte bildas naturligt svämtäcke kan surgörning vara intressant för att minska både ammoniak- och metanemissioner.

    Åtgärder som surgörning av svämtäcket för att minska lustgasemissioner visade sig inte behövas eftersom lustgasemissionerna var relativt låga, trots att svämtäcket var bortåt en halv meter tjockt. Den finhackade halmen som användes som strö, bildade ett slätt och tätt svämtäcke på gödselytan vilket troligen hämmande lustgasbildningen, till följd av att luften inte kunde penetrera skiktet. Så finhackningen av halmströ kan eventuellt vara i sig en tänkbar åtgärd, vilket också kan minska ströåtgången.

    Metanproduktionen från en rötkammare är ofta svår att mäta, och beräknas därför ofta indirekt utifrån producerad elproduktion. Ett exempel på nyckeltal för att visa klimateffektiviteten hos anläggningen visas där metanemissionerna från lager under sommaren var 10,2 % av producerad mängd metan från rötkammare vid enstegsrötning under 24 dagar respektive 5,5 % vid tvåstegsrötning under 48 dagar. På årsbasis blir procenttalen betydligt lägre eftersom emissionerna är låga under vintern.

  • Disputas: 2018-06-13 13:15 Room Å4001, Uppsala
    Stegeby, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Teoretisk kemi.
    MATTER-ANTIMATTER INTERACTIONS: The hydrogen-antihydrogen system and antiproton-matter interactions2018Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Ever since antiparticles were discovered their nature has been something of a mystery. They were postulated to be identical to regular particles except for having opposite charge, but this would imply that an equal amount of antiparticles and particles should have been created at the beginning of time. However, everywhere we look the Universe seems to be constituted of regular particles, giving rise to the question whether there is something else that differentiates antiparticles from regular particles, or if there is something amiss in the Standard Model of particle physics.

    This thesis focuses on a central system of study in this field, the hydrogen-antihydrogen system and the theory surrounding it, as well as an expansion into systems with an antiproton interacting with small molecules, bridging the fields of quantum physics and quantum chemistry.

    Methods expanding on the Born-Oppenheimer approximation for the interaction between the two atoms are presented. The resulting 2-body interaction potential is then used for creating a part of the basis in a non-adiabatic 4-body method in order to look for resonance states whose existence could impact cross-sections of hydrogen-antihydrogen scattering. The eigenfunctions obtained from the non-adiabatic method are used by extracting the 2-body hadronic density function and comparing it to the adiabatic wave function, for measuring the adiabaticity of the hydrogen-antihydrogen system.

    The antiproton-matter interaction is first investigated by a quantum dynamical approach of an antiproton scattering on molecular hydrogen, common products in high-energy collision experiments, continued by a study of the potential energy surfaces of an antiproton interacting with a range of functional groups present in the human body.

  • Engel, Fabian
    et al.
    Farrell, Kaitlin J.
    McCullough, Ian M.
    Scordo, Facundo
    Denfeld, Blaize A.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Dugan, Hilary A.
    de Eyto, Elvira
    Hanson, Paul C.
    McClure, Ryan P.
    Nöges, Peeter
    Nöges, Tiina
    Ryder, Elizabeth
    Weathers, Kathleen C.
    Weyhenmeyer, Gesa A.
    A lake classification concept for a more accurate global estimate of the dissolved inorganic carbon export from terrestrial ecosystems to inland waters2018Inngår i: The Science of Nature: Naturwissenschaften, ISSN 0028-1042, E-ISSN 1432-1904, Vol. 105, artikkel-id 25Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The magnitude of lateral dissolved inorganic carbon (DIC) export from terrestrial ecosystems to inland waters strongly influences the estimate of the global terrestrial carbon dioxide (CO2) sink. At present, no reliable number of this export is available, and the few studies estimating the lateral DIC export assume that all lakes on Earth function similarly. However, lakes can function along a continuum from passive carbon transporters (passive open channels) to highly active carbon transformers with efficient in-lake CO2 production and loss. We developed and applied a conceptual model to demonstrate how the assumed function of lakes in carbon cycling can affect calculations of the global lateral DIC export from terrestrial ecosystems to inland waters. Using global data on in-lake CO2 production by mineralization as well as CO2 loss by emission, primary production, and carbonate precipitation in lakes, we estimated that the global lateral DIC export can lie within the range of 0.70(-0.31)(+0.27) 1.52(-0.90)(+1.09) Pg C yr(-1) depending on the assumed function of lakes. Thus, the considered lake function has a large effect on the calculated lateral DIC export from terrestrial ecosystems to inland waters. We conclude that more robust estimates of CO2 sinks and sources will require the classification of lakes into their predominant function. This functional lake classification concept becomes particularly important for the estimation of future CO2 sinks and sources, since in-lake carbon transformation is predicted to be altered with climate change.

  • Disputas: 2018-06-12 13:00 E3, Stockholm
    Carlson, Magnus
    KTH, Skolan för teknikvetenskap (SCI), Matematik (Inst.), Matematik (Avd.).
    Abelian affine group schemes, plethories, and arithmetic topology2018Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    In Paper A we classify plethories over a field of characteristic zero. All plethories over characteristic zero fields are ``linear", in the sense that they are free plethories on a bialgebra. For the proof of this classification we need some facts from the theory of ring schemes where we extend previously known results. We also give a classification of plethories with trivial Verschiebung over a perfect field k of characteristic p>0.

    In Paper B we study tensor products of abelian affine group schemes over a perfect field k. We first prove that the tensor product G_1 \otimes G_2 of two abelian affine group schemes G_1,G_2 over a perfect field k exists. We then describe the multiplicative and unipotent part of the group scheme G_1 \otimes G_2. The multiplicative part is described in terms of Galois modules over the absolute Galois group of k. In characteristic zero the unipotent part of G_1 \otimes G_2 is the group scheme whose primitive elements are P(G_1) \otimes P(G_2). In positive characteristic, we give a formula for the tensor product in terms of Dieudonné theory. 

    In Paper C we use ideas from homotopy theory to define new obstructions to solutions of embedding problems and compute the étale cohomology ring of the ring of integers of a totally imaginary number field with coefficients in Z/2Z. As an application of the obstruction-theoretical machinery, we give an infinite family of totally imaginary quadratic number fields such that Aut(PSL(2,q^2)), for q an odd prime power, cannot be realized as an unramified Galois group over K, but its maximal solvable quotient can. 

    In Paper D we compute the étale cohomology ring of an arbitrary number field with coefficients in Z/nZ for n an arbitrary positive integer. This generalizes the computation in Paper C. As an application, we give a formula for an invariant defined by Minhyong Kim.

  • Aaboud, M.
    et al.
    Univ Mohamed Premier, Fac Sci, Oujda, Morocco.;LPTPM, Oujda, Morocco..
    Bergeås Kuutmann, Elin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Högenergifysik.
    Bokan, Petar
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Högenergifysik. Georg August Univ, Phys Inst 2, Gottingen, Germany.
    Brenner, Richard
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Högenergifysik.
    Ekelöf, Tord
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Högenergifysik.
    Ellert, Mattias
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Högenergifysik.
    Ferrari, Arnaud
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Högenergifysik.
    Gradin, Joakim
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Högenergifysik.
    Isacson, Max
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Högenergifysik.
    Mårtensson, Mikael
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Högenergifysik.
    Öhman, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Högenergifysik.
    Sales De Bruin, Pedro
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Högenergifysik.
    Zwalinski, L.
    CERN, Geneva, Switzerland..
    Measurement of differential cross-sections of a single top quark produced in association with a W boson at √s=13TeV with ATLAS2018Inngår i: European Physical Journal C, ISSN 1434-6044, E-ISSN 1434-6052, Vol. 78, nr 3, artikkel-id 186Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The differential cross-section for the production of a W boson in association with a top quark is measured for several particle-level observables. The measurements are performed using 36.1 fb(-1) of pp collision data collected with the ATLAS detector at the LHC in 2015 and 2016. Differential cross-sections are measured in a fiducial phase space defined by the presence of two charged leptons and exactly one jet matched to a b-hadron, and are normalised with the fiducial cross-section. Results are found to be in good agreement with predictions from several Monte Carlo event generators.

  • Disputas: 2018-06-08 13:00 Sal X, Uppsala
    Larsson, Germund
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Fakulteten för utbildningsvetenskaper, Institutionen för pedagogik, didaktik och utbildningsstudier.
    Förbrytelser och förvisningar: Bestraffningssystemet i de svenska läroverken 1905–19612018Doktoravhandling, monografi (Annet vitenskapelig)
    Abstract [en]

    The aim of this dissertation is to analyse the system of punishment at the upper secondary schools in Sweden during the twentieth century. The main research question is: how did the system of punishment function and change from 1905 to 1961? The investigations concentrate on the offences committed, the spatial features of the jurisdiction, the agents involved, as well as the systems of meaning that underscored the penal process. The analysis is mainly founded upon an extensive source material comprehending all expulsion cases at the upper secondary schools during the period.

    The dissertation enriches our understanding of how the system of punishment operated during the twentieth century. The pupil and his or her morals and conduct were at the heart of the system of punishment. It is shown that the hardest punishment, the expulsion, was not only passed for the most severe offences, but also for more banal infractions. Furthermore, the juridical system of the upper secondary schools stretched far beyond the physical milieu of the school yard. Offences committed in the public arena of the town, as well as the private institution of the household, stood grounds for excluding a pupil. Additionally, the relative importance of different types of agents that enacted the system changed over time. Headmasters and teachers were successively accompanied by new agents such as school physicians, the child protection agency as well as modern law enforcement personnel. Finally, the rationality – the historically specific system of meaning underlying the judgment of pupils’ offences – behind the decisions to issue the hardest punishment is examined. Ideas of conduct relating to gender and social class, values concerning truthfulness and deceitfulness, as well as ideas of physical attributes and their connection to intelligence and mental decease, all played parts in the examination of the offending pupils. In the end, the dissertation argues that the system of punishment was something more, and something else, then a mere part of the pedagogical practise of the upper secondary schools. In the system of punishment, internal school traditions converged with partially contradictory tendencies within society at large.

  • Disputas: 2018-06-12 09:00 Å2001, Uppsala
    Spiegelberg, Jakob
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Materialteori.
    Signal Processing Tools for Electron Microscopy2018Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The detection of weak signals in noisy data is a problem which occurs across various disciplines. Here, the signal of interest is the spectral signature of the electron magnetic chiral dichroism (EMCD) effect. In principle, EMCD allows for the measurement of local magnetic structures in the electron microscope, its spatial resolution, versatility and low hardware requirements giving it an eminent position among competing measurement techniques. However, experimental shortcomings as well as intrinsically low signal to noise ratio render its measurement challenging to the present day.   

    This thesis explores how posterior data processing may aid the analysis of various data from the electron microscope. Following a brief introduction to different signals arising in the microscope and a yet briefer survey of the state of the art of EMCD measurements, noise removal strategies are presented. Afterwards, gears are shifted to discuss the separation of mixed signals into their physically meaningful source components based on their assumed mathematical characteristics, so called blind source separation (BSS).    

    A data processing workflow for detecting weak signals in noisy spectra is derived from these considerations, ultimately culminating in several demonstrations of the extraction of EMCD signals. While the focus of the thesis does lie on data processing strategies for EMCD detection, the approaches presented here are similarly applicable in other situations. Related topics such as the general analysis of hyperspectral images using BSS methods or the fast analysis of large data sets are also discussed.

  • Meunier, Cécile
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Systematisk biologi.
    Hosseini, Sara
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Systematisk biologi.
    Heidari, Nahid
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Systematisk biologi.
    Maryush, Zaywa
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Systematisk biologi.
    Johannesson, Hanna
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Systematisk biologi.
    Multilevel Selection in the Filamentous Ascomycete Neurospora tetrasperma2018Inngår i: American Naturalist, ISSN 0003-0147, E-ISSN 1537-5323, Vol. 191, nr 3, s. 290-305Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The history of life has been driven by evolutionary transitions in individuality, that is, the aggregation of autonomous individuals to form a new, higher-level individual. The fungus Neurospora tetrasperma has recently undergone an evolutionary transition in individuality from homokaryosis (one single type of nuclei in the same cytoplasm) to heterokaryosis (two genetically divergent and free-ranging nuclear types). In this species, selection can act at different levels: while nuclei can compete in their replication and transmission into short-lived asexual spores, at the level of the heterokaryotic individual, cooperation between nuclear types is required to produce the long-lived sexual spores. Conflicts can arise between these two levels of selection if the coevolution between nuclear types is disrupted. Here, we investigated the extent of multilevel selection in three strains of N. tetrasperma. We assessed the ratio between nuclear types under different conditions and measured fitness traits of homo- and heterokaryotic mycelia with varying nuclear ratios. We show that the two nuclei have complementary traits, consistent with division of labor and cooperation. In one strain, for which a recent chromosomal introgression was detected, we observed the occurrence of selfish nuclei, enjoying better replication and transmission than sister nuclei at the same time as being detrimental to the heterokaryon. We hypothesize that introgression has disrupted the coevolution between nuclear types in this strain.

  • Disputas: 2018-06-11 13:00 Humanistiska teatern, Uppsala
    Petek, Nik
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Historisk-filosofiska fakulteten, Institutionen för arkeologi och antik historia.
    Archaeological Perspectives on Risk and Community Resilience in the Baringo Lowlands, Kenya2018Doktoravhandling, monografi (Annet vitenskapelig)
    Abstract [en]

    This historical ecological research provides a detailed insight into the risk avoidance and resilience building strategies in the Lake Baringo basin in Kenya through the lens of archaeology. It explores how changes in subsistence, habitation, and landscape shaped each other and how that affected the available strategies of risk avoidance and resilience building. While the focus is on the history and archaeology of the Ilchamus, a Maa community currently occupying the area, the research additionally investigated the late Holocene of the Baringo lowlands to provide a basis for the discussion on risk and resilience. A combination of remote sensing, foot surveys, excavation, and spatial statistic methods establishes a culture history for the region, showing that the Lake Baringo basin has been part of the pastoralist cultural sphere for the past three millennia and that the Rift Valley bottom possibly acted as a frontier between different archaeological cultures. By the end of the 18th or the beginning of the 19th century the area was occupied by Ilchamus. They established densely aggregated settlements and a vast irrigation system in order to enmesh themselves into the local, regional, and global exchange system. Through the exchange system, they would ensure their ‘social survival’ and build social contracts as part of their resilience building strategies, which continued to be practiced even as the Ilchamus subsistence and habitation practices as well as the political situation changed. However, as archaeological assemblages and ethnoarchaeological and historical data show, throughout their 200-year history community conformity and consolidation were central forces in the formation of an Ilchamus identity and a strong community resilience.

    The environmental degradation of the Lake Baringo area has been the subject of studies for almost a century with the subsistence practices of the local communities seen as a key cause for it. This research moves beyond blame but instead explores the options available and choices taken by the Ilchamus community in specific environmental and political contexts. I hope that this thesis provides some insights into new avenues of exploration of how we can develop and strengthen the resilience of vulnerable communities, such as Ilchamus.

  • Kuhne, Philipp
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Halvledarmaterial. Linköpings universitet, Tekniska fakulteten.
    Armakavicius, Nerijus
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Halvledarmaterial. Linköpings universitet, Tekniska fakulteten.
    Stanishev, Vallery
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Halvledarmaterial. Linköpings universitet, Tekniska fakulteten.
    Herzinger, Craig M,
    J. A. Woollam Company, Inc., Lincoln, NE, USA.
    Schubert, Mathias
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Halvledarmaterial. Linköpings universitet, Tekniska fakulteten.
    Darakchieva, Vanya
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Halvledarmaterial. Linköpings universitet, Tekniska fakulteten.
    Advanced Terahertz Frequency-Domain Ellipsometry Instrumentation for In Situ and Ex Situ Applications2018Inngår i: IEEE Transactions on Terahertz Science and Technology, ISSN 2156-342X, Vol. 8, nr 3, s. 257-270Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We present a terahertz (THz) frequency-domain spectroscopic ellipsometer design that suppresses formation of standing waves by use of stealth technology approaches. The strategy to suppress standing waves consists of three elements geometry, coating, and modulation. The instrument is based on the rotating analyzer ellipsometer principle and can incorporate various sample compartments, such as a superconducting magnet, in situ gas cells, or resonant sample cavities, for example. A backward wave oscillator and three detectors are employed, which permit operation in the spectral range of 0.1–1 THz (3.3–33 cm−1 or 0.4–4 meV). The THz frequency-domain ellipsometer allows for standard and generalized ellipsometry at variable angles of incidence in both reflection and transmission configurations. The methods used to suppress standing waves and strategies for an accurate frequency calibration are presented. Experimental results from dielectric constant determination in anisotropic materials, and free charge carrier determination in optical Hall effect (OHE), resonant-cavity enhanced OHE, and in situ OHE experiments are discussed. Examples include silicon and sapphire optical constants, free charge carrier properties of two-dimensional electron gas in a group III nitride high electron mobility transistor structure, and ambient effects on free electron mobility and density in epitaxial graphene.

  • Lindelöw, Camilla
    Södertörns högskola, Södertörns högskolebibliotek.
    Utvärdering och utforskande2018Inngår i: Världen där utanför: bibliotekariens roll som omvärldsbevakare och analytiker / [ed] Marja Haapalainen ; Christine Wallén, Stockholm: Kungliga biblioteket , 2018, s. 101-120Kapittel i bok, del av antologi (Annet vitenskapelig)
  • Codemo, Mario
    et al.
    Muschiol, Sandra
    Iovino, Federico
    Nannapaneni, Priyanka
    Plant, Laura
    Wai, Sun Nyunt
    Umeå universitet, Medicinska fakulteten, Institutionen för molekylärbiologi (Medicinska fakulteten). Umeå universitet, Medicinska fakulteten, Umeå Centre for Microbial Research (UCMR).
    Henriques-Normark, Birgitta
    Immunomodulatory Effects of Pneumococcal Extracellular Vesicles on Cellular and Humoral Host Defenses2018Inngår i: mBio, ISSN 2161-2129, E-ISSN 2150-7511, Vol. 9, nr 2, artikkel-id e00559-18Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Gram-positive bacteria, including the major respiratory pathogen Streptococcus pneumoniae, were recently shown to produce extracellular vesicles (EVs) that likely originate from the plasma membrane and are released into the extracellular environment. EVs may function as cargo for many bacterial proteins, however, their involvement in cellular processes and their interactions with the innate immune system are poorly understood. Here, EVs from pneumococci were characterized and their immunomodulatory effects investigated. Pneumococcal EVs were protruding from the bacterial surface and released into the medium as 25 to 250 nm lipid stained vesicles containing a large number of cytosolic, membrane, and surface-associated proteins. The cytosolic pore-forming toxin pneumolysin was significantly enriched in EVs compared to a total bacterial lysate but was not required for EV formation. Pneumococcal EVs were internalized into A549 lung epithelial cells and human monocyte-derived dendritic cells and induced proinflammatory cytokine responses irrespective of pneumolysin content. EVs from encapsulated pneumococci were recognized by serum proteins, resulting in C3b deposition and formation of C5b-9 membrane attack complexes as well as factor H recruitment, depending on the presence of the choline binding protein PspC. Addition of EVs to human serum decreased opsonophagocytic killing of encapsulated pneumococci. Our data suggest that EVs may act in an immunomodulatory manner by allowing delivery of vesicle-associated proteins and other macromolecules into host cells. In addition, EVs expose targets for complement factors in serum, promoting pneumococcal evasion of humoral host defense.

    Importance: Streptococcus pneumoniae is a major contributor to morbidity and mortality worldwide, being the major cause of milder respiratory tract infections such as otitis and sinusitis and of severe infections such as community-acquired pneumonia, with or without septicemia, and meningitis. More knowledge is needed on how pneumococci interact with the host, deliver virulence factors, and activate immune defenses. Here we show that pneumococci form extracellular vesicles that emanate from the plasma membrane and contain virulence properties, including enrichment of pneumolysin. We found that pneumococcal vesicles can be internalized into epithelial and dendritic cells and bind complement proteins, thereby promoting pneumococcal evasion of complement-mediated opsonophagocytosis. They also induce pneumolysin-independent proinflammatory responses. We suggest that these vesicles can function as a mechanism for delivery of pneumococcal proteins and other immunomodulatory components into host cells and help pneumococci to avoid complement deposition and phagocytosis-mediated killing, thereby possibly contributing to the symptoms found in pneumococcal infections.

  • Disputas: 2018-06-12 14:00 Hörsal 2, Uppsala
    Grant, Michael
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Företagsekonomiska institutionen. Uppsala University.
    MAKING ACQUISITIONS2018Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    This thesis examines acquisition-making, that is, activities and events leading up to the completion or cancellation of an acquisition. Acquisition-making involves people, from various areas of expertise, who are managed by and organized in what in this thesis is called a professional acquisition organization (PAO). The PAO is a small task force consisting of people from the acquirer and advisers assigned to make the acquisition. In addition to the PAO, decision-makers are obviously involved. However, the thesis especially examines the PAO’s activities. The setting is serial acquirers in which the PAO is managed by a special group of people appointed for this task.

    Acquisition-making is examined through a literature review of qualitative process research in M&A and three explorative case studies. These encompass a study of the role of the PAO in acquisition decision-making; a study of how strategic and financial rationales are produced; and a study of the role of management control systems in secret organizations such as PAOs.

    The findings of these studies contribute to our knowledge about how acquisitions are made in three ways. First, the findings show how the PAO plays a critical role in acquisition decision-making, emanating from a division of labor between the PAO and decision-makers. This enables the PAO to enhance or attenuate the perceived benefits of an acquisition when informing decision-makers. The respective purposes would be to receive approval for the acquisition, or to show improved performance after it is made. Second, the findings show how the key reasons for making an acquisition, through the strategic and financial rationales, are made by judgments based on intuitive expertise. Thus, the study provides an explanation for and understanding of how concepts such as cash flows are used in evaluating acquisitions. This implies that the expertise of the practitioners producing the strategic and financial rationales is of utmost importance for acquisition decisions, probably more so than the tools used. Third, the findings show that management control systems are important for how confidential information is concealed and made visible in acquisition-making, revealing different categories of secrets to different insiders and outsiders throughout acquisition-making.

  • Carlson, Magnus
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Matematik (Inst.), Matematik (Avd.).
    Bauer, Tilman
    KTH, Skolan för teknikvetenskap (SCI), Matematik (Inst.), Matematik (Avd.).
    Tensor products of affine and formal abelian groupsManuskript (preprint) (Annet vitenskapelig)
    Abstract [en]

    In this paper we study tensor products of affine abelian group schemes over a perfect field k. We first prove that the tensor product G_1 ⊗ G_2 of two affine abelian group schemes G_1,G_2  over a perfect field k exists. We then describe the multiplicative and unipotent part of the group scheme G_1 ⊗G_2. The multiplicative part is described in terms of Galois modules over the absolute Galois group of k. We describe the unipotent part of G_1 ⊗ G_2 explicitly, using Dieudonn\'e theory in positive characteristic. We relate these constructions to previously studied tensor products of formal group schemes.

  • Nilsson, Harald
    Uppsala universitet, Enheten för musik och museer, Gustavianum, Uppsala universitetsmuseum, Myntkabinettet.
    Hendrik Mäkeler till nya uppdrag2017Inngår i: Svensk Numismatisk Tidskrift, ISSN 0283-071X, nr 8, s. 183-184Artikkel i tidsskrift (Annet (populærvitenskap, debatt, mm))
  • Grimelius, Lars
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för immunologi, genetik och patologi, Experimentell och klinisk onkologi.
    Åkerström, Göran
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för kirurgiska vetenskaper, Endokrinkirurgi.
    Biographical item: "Henry Johansson in memoriam" in Upsala Journal Of Medical Sciences, vol 122, Issue: 4, pp 260-2612017Annet (Annet (populærvitenskap, debatt, mm))
  • Nele Mäger, Katrin
    et al.
    Tallinn University of Technology, Estonia.
    Just, Alar
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Development of Design Equations for the Component Additive Method for Paroc eXtra2017Rapport (Annet vitenskapelig)
    Abstract [en]

    This report details the development of effective thermal properties and design equations for Paroc eXtra which can be used for the improved component additive method for fire design of timber structures.  The results are validated with full scale fire tests where such reports are available. 

  • Fotrousi, Farnaz
    et al.
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för programvaruteknik.
    Seyff, Norbert
    University of Applied Sciences and Arts Northwestern Switzerland, CHE.
    Börstler, Jürgen
    Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, Institutionen för programvaruteknik.
    Ethical Considerations in Research on User Feedback2017Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Collecting and using user feedback as a method to support requirements engineering, might undermine user rights. This becomes apparent when looking at related areas, e.g., research in user experience, where collecting user feedback also plays an important role.  In such settings, researchers need to ensure that the stakeholders’ rights and integrity are respected. This paper identifies and discusses some of the ethical challenges and issues a researcher can face, using an example case. Focusing on user feedback, this case can serve as an example for CrowdRE, i.e. several of our findings might apply to CrowdRE in general. However, further research is needed as our work mainly reflects the challenges experienced by the authors of this paper.

  • Honfi, Daniel
    et al.
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Williams Portal, Natalie
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Leander, John
    KTH Royal Institute of Technology, Sweden.
    Larsson Ivanov, Oskar
    Lund University.
    Björnsson, Ívar
    Lund University, Sweden.
    Plos, Mario
    Chalmers University of Technology; Sweden.
    Zandi, Kamyab
    Chalmers University of Technology, Sweden.
    Carneiro, Erica
    NCC AB, Sweden.
    Lechner, Thomas
    NCC AB; Sweden.
    Magnusson, Jonas
    NCC AB, Sweden.
    Gabrielsson, Henrik
    Tyréns AB, Sweden.
    Inspection and monitoring of bridges in Sweden2018Rapport (Annet vitenskapelig)
    Abstract [en]

    This report provides an overview about recent research activities and current practice concerning inspection and monitoring of the structural performance of bridges and the related decision-making process. A brief review of common methods of collecting information on structural performance of bridges is presented, followed by a description of the use of the information collected in structural analysis and maintenance planning. An overview about the state of the art is given including recent scientific developments. Finally, the current Swedish practice for bridge management is presented.

  • Disputas: 2018-06-11 13:00 2001, Ångströmlaboratoriet, Uppsala
    Engelhardt, Ilka. A. D.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Rymd- och plasmafysik.
    Plasma and Dust around Icy Moon Enceladus and Comet 67P/Churyumov-Gerasimenko2018Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Saturn's moon Enceladus and comet 67P/Churyumov-Gerasimenko both are examples of icy solar system objects from which gas and dust flow into space. At both bodies, the gas becomes partly ionized and the dust grains get charged. Both bodies have been visited by spacecraft carrying similar Langmuir probe instruments for observing the plasma and the charged dust. As it turns out, the conditions at Enceladus and the comet are different and we emphasize different aspects of their plasma environments. At Enceladus, we concentrate on the characteristic plasma regions and charged dust. At the comet, we investigate the plasma and in particular plasmavariations and cold electrons.

    At Enceladus, internal frictional heating leads to gas escaping from cracks in the ice from the south pole region. This causes a plume of gas, which becomes partially ionized, and dust, becoming charged. We have investigated the plasma and charged nanodust in this region by the use of the Langmuir probe (LP) of the Radio and Plasma Wave Science (RPWS) instrument on Cassini. The dust charge density can be calculated from the quasineutrality condition, the difference between ion and electron density measurements from LP. We found support for this method by comparing to measurements of larger dust grains by the RPWS electric antennas. We use the LP method to find that the plasma and dust environment of Enceladus can be divided into at least three regions. In addition to the well known plume, these are the plume edge and the trail region.

    At the comet, heat from the Sun sublimates ice to gas dragging dust along as it flows out into space. When the neutral gas molecules are ionized, by photoionization and electron impact ionization, we get a plasma. Models predict that the electron temperature just after ionization is around 10 eV, but that collisions with the neutral gas should cool the electron gas to below 0.1 eV. We used the Langmuir probe instrument (LAP) on Rosetta to estimate plasma temperatures and show a co-existence of cold and warm electrons in the plasma. We find that the cold plasma often is observed as brief pulses not only in the LAP data but also in the measurements of magnetic field, plasma density and ion energy by other Rosetta plasma instruments. We interpret these pulses as filaments of plasma propagating outwards from a diamagnetic cavity, as predicted by hybrid simulations. The gas production rate of comet 67P varied by more than three orders of magnitude during the Rosetta mission (up to March 2016). We therefore have an excellent opportunity to investigate how the electron cooling in a cometary coma evolves with activity. We used a method combining LAP and the Mutual Impedance Probe (MIP) for deriving the presence of cold electrons. We show that cold electrons were present intermittently during a large part of the mission and as far out as 3 AU. Models suggest only negligible cooling and we suggest that the ambipolar field keeps the electrons close to the nucleus and giving them more time to lose energy by collision.

  • Disputas: 2018-06-08 09:00 Kollegiesalen, Stockholm
    KARIMNIA, ELAHE
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Urbana och regionala studier.
    Producing Publicness: Investigating the Dialectics of Unintended Consequences in Urban Design  - Practices in Stockholm and Malmö2018Doktoravhandling, monografi (Annet vitenskapelig)
    Abstract [en]

    The creation of public space is intended to contribute to the civic infrastructure of a city. The conventional dichotomy of intentions versus outcomes in urban design practice posits that, while intentions represent more abstract thinking about the various facets of publicness, outcomes are the manifest realizations of those intentions in public spaces. This study grounds itself in an exploration of this intention-outcome gap to examine how urban design facilitates the production of publicness, by means of which public spaces can enable appropriations, i.e., the practices of togetherness, encounters, and expressions of different publics. Analysing the appropriations as unintended consequences is about the planning and design process, by which publicness is produced through larger strategies; and, the process of use, by which publicness is socially experienced and contested.

    This research applies a comparative case study approach, as examples of brownfield developments and producing ‘city-like’ (stadsmässighet) urban environments in two practices in Sweden: the Liljeholmstorget Transit Hub in Stockholm and the Western Harbour Waterfront in Malmö. The Liljeholmstorget examines negotiations of land uses and trade-offs with private actors, and its publicness addresses informal togetherness and passive encounters in relation to collective routines of commuting and consumption. The Western Harbour Waterfront reveals a determined process to promote the city’s economic growth and image; planned for the well-being of a specific type of public, which was later contested by unexpected users and their unplanned expressions.

    Comparative analysis demonstrates appropriations as welcome phenomena in urban design because they emphasize the dynamic and contingent characteristics of publicness.