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Abstract The contact force development for two types of polymeric elastoplastic particles subjected to different triaxial loading conditions was studied experimentally utilising a unique triaxial testing apparatus. In order to evaluate the experimental results, a finite element analysis was performed. The experimental findings highlighted the importance of contact dependence, which manifested itself in two principally different ways. Firstly, a reduced stiffness was observed when plastic deformation ceased to be fully contained, which, depending on the loading conditions, occurred at an engineering strain of about 5–10%. Secondly, a markedly increased stiffness was observed when particle confinement inhibited further plastic deformation, making elastic volume reduction the predominant deformation mode. The experimental results could be well reproduced by the numerical simulations, provided that isotropic hardening was included in the elastoplastic model. In an attempt to invariantly describe the data, a nominal contact pressure was determined as a function of the volumetric constraint of the particle. This resulted in an adequate collapse of results obtained for different loading conditions onto a single master curve at large volumetric constraint. In summary, this paper should be considered as a step along the pathway towards our long term goal of introducing novel and improved contact models.

Atherosclerosis is an inflammatory disease that can be generalized, affecting more than one arterial bed simultaneously, or localized, manifested in one system. Ultrasound based measurements of plaque textural features, such as low grey scale median (GSM), echolucent (hypoechoic) plaque types and juxtaluminal black (hypoechoic) area (JBA) are manifestation of potentially unstable lesions. Conventional carotid IMT (intima media thickness) and the recently introduced IM-GSM (echogenicity of the intima media complex) are important measures of subclinical atherosclerosis and are used to predict future ischemic events. The aims of this thesis were to study, in detail, the systemic nature of atherosclerosis by evaluating the carotid disease burden contralateral to symptomatic arteries, determining the relationship between proximal (subclinical atherosclerosis) and distal segments (well established disease) of the same artery and comparing local plaque features with systemic burden of atherosclerosis disease. In addition, the effect of statins on carotid plaque echogenicity was evaluated in a systematic review and meta-analysis. Methods: We have measured ultrasound-based textural carotid plaque features (GSM, JBA, entropy, coarseness), surface morphology, as well as IMT and IM-GSM. An in-house custom developed research software package was used for plaque feature extraction. For the meta-analysis we used Comprehensive Meta-Analysis version 3 software. Results: Study 1. In 39 patients, the carotid plaques contralateral to symptomatic arteries had similar morphological and textural features to those in the symptomatic arteries and are more vulnerable than those in asymptomatic arteries; more often mildly or markedly irregular with more vulnerable textural plaque features (lower GSM and larger JBA). Study 2. In 87 asymptomatic patients, an increased IMT in CCA correlated with plaque irregularities in the bifurcation and ICA while IM-GSM was closely related to plaque echogenicity (GSM), and other textural plaque features. Study 3. In the same cohort in study 2, patients with previous disease in the coronary arteries had higher IMT and lower IM-GSM and those with prior stroke had lower IM-GSM. Neither IMT nor IM-GSM was different between patients with and without previous lower extremity disease. IM-GSM decreases significantly with increasing number of arterial territories p<0.001 (asymptomatic vs symptoms in one vs multiple arterial systems) but conventional IMT was not different between groups p=0.49. Study 4. In a meta-analysis of 9/580 identified studies including 566 patients with 7.2 months follow-up, a consistent increase in the carotid plaques echogenicity after statin therapy, was reported. The perpetual (over 12 months) effects of which were shown in a meta-regression analysis to be related to changes in hsCRP. Conclusion: Symptomatic patients have similar plaque morphology and textural features of vulnerability in the contralateral carotid system, compared with asymptomatic ones. In the latter, measurements of proximal disease reflect distal pathology and the number of affected arteries. Finally, statin therapy and the drop of LDL cholesterol result in better plaque stability and optimum control of arterial inflammation, shown by arterial wall echogenicity and hsCRP changes, respectively.

Uppsatsen ämnar besvara vilka aktiebolagsrättsliga skillnader det finns inom EU 25 för att starta och driva ett privat aktiebolag jämfört med den svenska aktiebolagslagens regler. Aktiebolagsrättsliga skillnader som undersöks generellt inom EU 25 är kapitalkrav, bolagsstyrning, aktieägare samt bolagsskatt. Utöver dessa fyra kategorier undersöks även bolagsbildning och bolagsstämma i fem länder som detaljstuderats. Sverige, Frankrike, Storbritannien, Tjeckien och Tyskland.

For a long time, Roman ideal sculptures have primarily been studied within the tradition of Kopienkritik. Owing to some of the theoretical assumptions tied to this practice, several important aspects of Roman visual culture have been neglected as the overall aim of such research has been to gain new knowledge regarding assumed Classical and Hellenistic models. This thesis is a collection of three studies on Roman ideal sculpture. The articles share three general aims: 1. To show that the practice of Kopienkritik has, so far, not produced convincing interpretations of the sculpture types and motifs discussed. 2. To show that aspects of the methodology tied to the practice of Kopienkritik (thorough examination and comparison of physical forms in sculptures) can, and should, be used to gain insights other than those concerning hypothetical Classical and Hellenistic model images. 3. To present new interpretations of the sculpture types and motifs studied, interpretations which emphasize their role and importance within Roman visual culture. The first article shows that reputed, post-Antique restorations may have an unexpected—and unwanted—impact on the study of ancient sculptures. This is examined by tracing the impact that a restored motif ("Satyrs with cymbals") has had on the study of an ancient sculpture type: the satyr ascribed to the two-figure group "The invitation to the dance". The second article presents and interprets a sculpture type which had previously gone unnoticed—The satyrs of "The Palazzo Massimo-type". The type is interpreted as a variant of "The Marsyas in the forum", a motif that was well known within the Roman cultural context. The third article examines how, and why, two motifs known from Classical models were changed in an eclectic fashion once they had been incorporated into Roman visual culture. The motifs concerned are kalathiskos dancers, which were transformed into Victoriae, and pyrrhic dancers, which were also reinterpreted as mythological figures—the curetes. At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 1: Accepted. Paper 3: Accepted.

Denna studies syfte är att ta reda på och utveckla kunskap om könsnormer om maskulinitet och andra normer som kan ha en verkan på pojkars gymnasieval till det estetiska programmets inriktning bild och formgivning. För att få reda på detta används intervjumetoden halv-strukturerad intervju tillsammans med en arrangerad fokusgrupp. Fokusgruppen utgör en homogen grupp av tre pojkar i det estetiska programmets bild och formgivning. Resultatet samt analysen och diskussionen av intervjun ger läsarna en inblick i vad pojkarna i intervjun har för upplevelser i att gå det estetiska programmet bild och formgivning. Pojkarna som deltar i studien bär på förstahandsinformation om möten de har haft med elever på skolans andra program samt människor utanför skolmiljön. Genom dessa möten blir pojkarna i studien utsatta för olika normer, könsnormer och maskuliniteter som finns i samhället men som de väljer att avvika från. Pojkarna i studien ställer sig mot maskulina könsnormer i deras samhälle som att bild är ett intresse för flickor samt att pojkar förväntas gå gymnasieprogram som säkrar framtida yrken med bra lön.

T regulatory cells (Tregs) have been extensively studied in patients with cancer or autoimmunity. These cells hamper the immune system’s ability to clear tumor cells in cancer patients. In autoimmune diseases, on the other hand, they are not able to restrain autoreactive immune responses. If we manage to understand Tregs and their role in health and diseases we may be able to develop better immunomodulatory therapies. Early studies demonstrated that tolerance was maintained by a subset of CD25+ T-cells. CD25 was the earliest marker for Tregs and is still often used to define these cells. Several Treg-associated markers have been suggested throughout the years. However, these markers can be upregulated by activated T-cells as well. The most specific marker for Tregs is currently the transcription factor forkhead box P3 (FoxP3). In this thesis, we investigated the presence of CD25- Tregs in patients with B-cell malignancies and in patients with autoimmunity. These cells were identified in both patient groups. Further, patients with B-cell malignancies often have high levels of soluble CD25 (sCD25) in the periphery. In our patient cohorts, the level of peripheral Tregs correlated with the level of sCD25 in patients with lymphoma. Tregs were shown to release sCD25 in vitro and sCD25 had a suppressive effect on T-cell proliferation. These data show that Tregs may release CD25 to hamper T-cell proliferation and that this may be an immune escape mechanism in cancer patients. Previous studies have demonstrated that an increased infiltration of FoxP3+ cells into lymphoma-affected lymph nodes is associated with a better patient outcome. This is in contrast to studies from non-hematological cancers where an increased presence of Tregs is associated with a poor prognosis. Since previous studies have shown that Tregs are able to kill B-cells, we wanted to investigate if Tregs are cytotoxic in patients with B-cell tumors. In the subsequent studies, Tregs from patients with B-cell lymphoma and B-cell chronic lymphocytic leukemia (CLL) were phenotyped to investigate the presence of cytotoxic markers on these cells. FoxP3-expressing T-cells from both patients with CLL and B-cell lymphoma displayed signs of cytotoxicity by upregulation of FasL and the degranulation marker CD107a. Tregs from CLL patients could further kill their autologous B-cells in in vitro cultures. Taken together the studies in this thesis have demonstrated two possible new functions of Tregs in patients with B-cell malignancies and the presence of CD25- Tregs in both cancer and autoimmunity.

A lot has changed since that day on December 17, 1903 when the Wright brothers made the first powered manned flight. Even though the concepts behind flying are unaltered, appearance of stat-of-the-art modern aircrafts has undergone a massive evolution. This is mainly owed to our deeper understanding of how to harness and optimize the interaction between fluid flows and aircraft bodies. Flow passing over wings and different junctions on an aircraft faces numerous local features, for instance, acceleration or deceleration, laminar or turbulent state, and interacting boundary layers. In our study we aim to characterize some of these flow features and their physical roles. Primarily, stability characteristics of flow over a wing subject to a negative pressure gradient are studied. This is a common condition for flows over swept wings. Part of the current numerical study conforms to existing experimental studies where a passive control mechanism has been tested to delay laminarturbulent transition. The same flow type has also been considered to study the receptivity of three-dimensional boundary layers to freestream turbulence. The work entails investigation of effects of low-level freestream turbulence on crossflow instability, as well as interaction with micron-sized surface roughness elements. Another common three-dimensional flow feature arises as a resultof stream-lines passing through a junction, the so-calledcorner-flow. For instance, thisflow can be formed in the junction between the wing and fuselage on aplane.A series of direct numerical simulations using linear Navier-Stokes equationshave been performed to determine the optimal initial perturbation. Optimalrefers to perturbations which can gain the maximum energy from the flow overa period of time. In other words this method seeks to determine theworst-casescenario in terms of perturbation growth. Here, power-iterationtechnique hasbeen applied to the Navier-Stokes equations and their adjoint to determine theoptimal initial perturbation. Recent advances in super-computers have enabled advance computational methods to increasingly contribute to design of aircrafts, in particular for turbulent flows with regions of separation. In this work we investigate theturbulentflow on an infinite wing at a moderate chord Reynolds number of Re= 400,000 using a well resolved direct numerical simulation. A conventional NACA4412 has been chosen for this work. The turbulent flow is characterizedusing statistical analysis and following time history data in regions with interesting flow features. In the later part of this work, direct numerical simulation has been chosen as a tool to mainly investigate the effect of freestream turbulence on the transition mechanism of flow from laminar to turbulent around a turbine blade. QC 20151125

Vi har i denna studie undersökt vilka möjligheter sex skolors likabehandlingsplaner ger för att arbeta för och med likabehandling. Detta har vi gjort genom att utföra kvalitativa textanalyser på skolornas likabehandlingsplaner där vi har studerat hur planerna svarar mot skollagen, Allmänna råd för arbetet mot diskriminering och kränkande behandling (2012) samt Lika rättigheter i skolan? (2012). Vi har vidare utgått ifrån fyra strategier för likabehandlingsarbete som vi har hämtat från Kevin Kumashiros artikel Towards a Theory of Anti – Oppressive Education (2000). Vi har studerat vilka strategier skolornas likabehandlingsplaner använder sig av i sitt likabehandlingsarbete och om de i sin tur har någon inverkan på konstruktionen ”vi” och ”dom”. Resultatet av denna studie blev att skolorna svarar mot skollagen, Allmänna råd för arbetet mot diskriminering och kränkande behandling (2012) samt Lika rättigheter i skolan (2012). Vi kom vidare fram till att skolorna i sina likabehandlingsplaner använder sig av olika strategier för likabehandlingsarbete och att dessa strategier kan ha en inverkan på konstruktionen ”vi” och ”dom”.