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Uppsala universitet Atom- Och Molekylfysik
This thesis concerns methods for electronic structure calculations and some applications of the methods.The augmented planewave (APW) basis set and it’s relatives LAPW (linearised APW) and APW+lo (local orbitals) have been widely used for electronic structure calculations. Here a modification of the APW basis set based on a transformation of the basis functions from a curvilinear coordinate system. Applications to a few test systems show that the modified basis set may speed up electronic structure calculations of sparse systems.The local density approximation (LDA) is used in density functional theory. Although it is the simplest possible approximation possible for the unknown exchange-correlation energy functional, it has proven to give quite accurate results for a wide range of systems. LDA fails in systems where the non-local effects are important. By including non-local effects by adding an orbital dependent term to the energy functional, through for example the LDA+U method, the calculated properties of many materials are closer to experimental observations. In the thesis the most general formulation of the LDA+U method is presented and a new way of interpreting the results of a calculations by formulating the orbital dependent part of the energy functional in terms of multipole momentum tensors. Applications to some early actinide systems leads to a reformulations of Hund’s rules for polarisations associated with the spin and orbital magnetic moment and a suggestion for similar rules, Katt’s rules, valid in the strong spin orbit coupling regime.
978-91-554-7407-2 / Link / Bultmark , Fredrik / 2009

A key question related to climate change projections is how will aquatic systems respond to changes in variables such as temperature and precipitation? This thesis uses GWLF, a simple catchment scale model to explore potential impacts of climate change on water quantity and quality.River discharge and nutrient loads were modelled for several warmer world scenarios. For one catchment in New York, USA changes in annual dissolved phosphorus loads decreased along with annual streamflow, and particulate phosphorus loads increased for a single future climate scenario. For the Galten catchment of Lake Mälaren, Sweden, the spring melt peak observed historically was reduced for six future scenarios. Peak runoff and dissolved phosphorus and nitrogen load maxima occurred in winter rather than early spring.A synthesis of model results for dissolved inorganic nitrogen (DIN) loadings for five European catchments showed changes in the timing and magnitude of peak DIN load for several future scenarios. In northern Europe, changes were largely due to increased winter streamflow and reduced snow pack and spring melt runoff. In western Europe, DIN loads increased in winter or early spring due to increased precipitation.The biological response for a warmer future scenario was modelled for the Galten basin of Lake Mälaren using GWLF coupled to a lake phytoplankton model and a physical lake model. An increase in cyanobacteria biomass accompanied by a decline in diatom biomass resulted from changes in the timing of nutrient export from the catchment. The projected increase in lake temperature favored an overall increase in total phytoplankton biomass.Lastly, a method based on hourly measurements of colored dissolved organic matter (CDOM) fluorescence provides the appropriate data for dissolved organic carbon (DOC) model parameterization and may also be used for surveillance of organic matter inputs to lakes.
978-91-554-6980-1 / Link / Moore , Karen / 2007

Uppsala universitet Informationsteknik
978-1-4244-3677-4 / Link / Li , Jian / 2009

This thesis in a tripartite disposition is intended to analyse and synthesize conscious and unconscious reminiscences of reading Homer in Jean Giono’s works, especially the figure of Odysseus polutropos or polumècanos, and to elucidate how the modern author through his characters regenerates this topos.Despite the fact that these two authors sprang from, in time and space, remotely situated places in the Mediterranean soil, the agrarian and manufacturing societies to which they belonged had many similarities. But, at a distance of thirty centuries, the comparison would seem risky if, in these two cases, the account did not intervene after a major conflict (The Trojan War and The First World War respectively) that changed the course of history. This form of ”logos meta polémon”, exposing real and fictional exploits, imposed itself upon the minds of those who survived the cataclysm.Following Giono in his real and imaginary wanderings, this study is intended to show how the circularity of thought interweaves with the aspiration to discover new horizons. Impetus, or the enthusiasm for treading on new grounds, harmonizes with the myth of circumnavigation, where the author with his characters, being a prey to distrust or in the grip of Gorgon, is in search of his self. Assuming different aspects of Odysseus´s personality, and adopting his attitudes, Giono’s vagabonds attempt to measure the world in order to survive.The study embraces the accommodation between the myth and the truth, the latter considered as the “deeper truth” that mythopoeic fictions often embody. Odysseus’s skill in giving verisimilitude to his falsehood is shown in the wanderers’ constant laborious struggle to obtain pitance, everyday existence. In this art of survival, the cunning (dólos) and the reasoning (logos), led by the mètis (the stratagem of intelligence), influence the action and the structure of the novel.The chapter that treats of poïésis undertakes to intertwine the composition of the images with the musicality of the texts. The personification of the elements, the most important source of Giono’s art, perpetuating their divinisation practised by Homer, conserves the alétheia (the truth/non forgetfulness) and this, in turn, guarantees the mnesis (the memory).Analysis of the creation of the text, the poïésis, in which the author’s inner voice is revealed, leads to a series of questions regarding the work´s opening with the torch towards the future.The study never loses sight of the fact that the whole of literature reflects a society in which the author is formed, and in which he tries to distinguish himself from others through his work. From there emanate socio-economic points of view, such as those Gabriel Germain presented regarding the bard´s status: from the first inspiration to the cunning mastery of the language.The study in the confluence of the literary and the socio-historical approaches does not aim to restrain the essentials of imagination in Jean Giono’s works, but to consider their origin as the fundamental experience of those who in literature aspire to attain the universal.
978-91-506-2035-1 / Link / Ivier , Marica / 2008

The main purpose of this thesis is to study the reasons behind the Swedish decision not to become a full member of the EEC in the 1960's and 1970's.During this period, Sweden adapted a so called contra-cyclical economic policy characterised by capital and exchange regulations and discriminating establishment rules against foreign citizens. These rules were however incompatible with a membership in the EEC. At the same time, trade with the EEC-countries was of great importance. Therefore an agreement that safeguarded an independent economic policy at the same time as it ensured Swedish trade was considered as urgent and a number of exceptions from the Treaty of Rome were demanded in this respect. Sweden, however, referred these exceptions to areas connected with neutrality and security policy in the belief that this would win sympathy from the Swedish opposition parties as well as from the EEC. This strategy, however, failed with respect to the EEC-countries and a widely spread opinion among these countries was that Sweden only used the neutral-policy-argument as an excuse for safeguarding Swedish domestic policy interests. This led to a massive critique against Sweden. In order not to be blamed for reducing the importance of the policy of neutrality the opposition parties, however, did not question the Swedish arguments which led to a long period of silence in the Swedish EEC-debate.This explanation for the Swedish actions towards the EEC has not been given enough attention by prior researchers. The functionalistic view on the European integration in which integration in one area more or less automatically leads to an extended integration in others is also questioned. This thesis in contrast supports the intergovernmentalistic view on European integration and suggests that economic integration in one area in some cases, for political reasons, encourages self determination in others.
978-91-554-7552-9 / Link / Magnusson , Erik / 2009

N/A / Link / Andersson , Staffan / 2008

Uppsala universitet Matematik
N/A / Link / Mazorchuk , Volodymyr / 2008

Uppsala universitet Dermatologi Och Venerologi
Moisturizers are used in various types of dry skin disorders, but also by people with healthy skin. It is not unusual that use of moisturizers is continued for weeks, months, or even years. A number of moisturizers have been shown to improve the skin barrier function, while others to deteriorate it, but the reason for observed effects remains unknown. Further understanding of the mechanism by which long-term treatment with moisturizers influences the skin barrier would have clinical implications, as barrier-deteriorating creams may enhance penetration of allergens or irritants and predispose to dry skin and eczema, while barrier-improving ones could reduce many problems.The present research combined non-invasive techniques with analyses of skin biopsies, allowing studies of the epidermis at molecular and cellular level. Test moisturizers were examined on healthy human volunteers for their effect on the skin barrier, with regard to such factors as pH, lipid type, and presence of a humectant, as well as complexity of the product. After a 7-week treatment with the moisturizers, changes in transepidermal water loss, skin capacitance, and susceptibility to an irritant indicated a modified skin barrier function. Moreover, the mRNA expression of several genes involved in the assembly, differentiation and desquamation of the stratum corneum, as well as lipid metabolism, was altered in the skin treated with one of the moisturizers, while the other moisturizer induced fewer changes.In conclusion, long-term use of moisturizers may strengthen the barrier function of the skin, but also deteriorate it and induce skin dryness. Moisturizers have also a significant impact on the skin biochemistry, detectable at molecular level. Since the type of influence is determined by the composition of a moisturizer, more careful selection of ingredients could help to design moisturizers generating a desired clinical effect, and to avoid ingredients with a negative impact on the skin.
978-91-554-7296-2 / Link / Buraczewska , Izabela / 2008

Presented in this thesis are some basic concepts and applications of seismic hazard analysis and the elements that influence the amplitude and geometric attenuation of earthquake ground motion. This thesis centers on the identification of the styles of failure, focal mechanisms, and the state of regional stress in the study area. Seismic hazard is a complex problem often involving considerable uncertainties. Therefore it is reasonable to consider different seismic hazard analysis approaches in order to as robustly as possible define zones of different levels of hazard. With the aim of characterizing and quantifying hazard in the east African region of Eritrea and its surroundings, a study is included in the thesis presenting hazard maps constructed using two non-parametric probabilistic seismic hazard analysis (PSHA) approaches. Peak ground acceleration (PGA) values for 10% probability of exceedence in 50 years are computed at given grid points for the whole selected area and results from both methods are compared.Other aspects addressed in the thesis include the determination of source parameters of selected earthquakes that occur in the Afar region. The styles of faulting, the mechanisms involved during the rupture process and the states of stress along the major tectonic features are also highlighted. Source parameters for selected events in the region were re-evaluated and improved solutions obtained. An aftershock sequence in the Hengill volcanic area in SW Iceland, following the major event that occurred on June 4, 1998, was used to investigate improved methodologies for moment tensor using a relative approach. The sensitive and spatially dense seismic network in this area reveals large sets of clustered events allowing the power of the new methodology to be demonstrated and providing greater insight into the tectonic implications of the activity in the area.
91-554-6721-0 / Link / Hagos , Lijam Zemichael / 2006

Attenuation of acid mine drainage (AMD) metals originating from abandoned mines and waste rock dumps is investigated in this thesis at Slättberg in central Sweden, where acid mine leachate has been discharging for over 70 years into the receiving wetland stream and mire. Risk assessment of AMD and related polluted lands requires a holistic approach that is able to study the complexity of pollution emissions and impacted landscapes. In this thesis a link between geochemical contaminant fate modelling and landscape analysis is presented for AMD risk assessment. A simple geochemical landscape analysis tool is developed to analyse and model geochemical abundances, geochemical gradients, geochemical flow patterns and geochemical barriers in the studied stream and mire sediments. Sampling locations at geochemical barriers are identified using landscape geochemical and GIS methods. A sequential chemical extraction procedure is used to investigate fractions which are expected to act as potential sinks of the six studied metals (Cu, Fe, Mn, Ni, Pb and Zn) in the sediments. For data modelling robust statistical methods of Exploratory Data Analysis are used to treat small sample sizes with multimodal character and outlying values. The spatial variability of metal retention in the sediments is studied by multivariate data analysis methods. Results show that the developed simple geochemical landscape analysis method can be used efficiently for the risk assessment of toxic mine contaminants in the complex receiving wetland landscape. It is suggested by the analysis that the oxidising geochemical barrier in the stream sediments can be sufficiently characterised by the distribution of Fe fractions. At the AMD discharge location metal sulphide formation and organic matter adsorption control metal retention in the mire. Mires are very sensitive to changes in hydrological conditions and drying of the sediments leads to erosion and hence the release of adsorbed metals to the environment.
91-554-6601-X / Link / Szucs , Andrea / 2006

Axolotl embryos have previously been used to study neural crest cell migration. In embryos of the normal wild type, neural crest cells migrate subepidermally to form pigment cells. In the trunk of the white mutant embryo, these cells are unable to migrate, possibly due to an inherited delay in the maturation of the local extracellular matrix. The present investigation reveals a reduced incorporation of [35S]sulfate into PG-M/versican-like proteoglycans synthesized in epidermal explants from the dorsal trunk of white mutant embryos during stages pertinent to migration. This is the major form of proteoglycans in the subepidermal matrix, where they are assembled in large disulfide-stabilized supramolecular complexes. The reduction in [35S]sulfate incorporation is not due to qualitative differences between wild-type and white mutant proteoglycans but is paralleled by a reduced expression of mRNA for the core protein of the PG-M/versican-like proteoglycan. We conclude that a reduced amount of these proteoglycans is produced by the white mutant embryo during the period critical for migration.
N/A / Link / Stigson , Michael / 1997

N/A / Link / Tan , Xing / 2009

Uppsala universitet Informationsteknik
N/A / Link / Roberts , William / 2008

N/A / Link / Pérez-Neira , Ana I. / 2008

Uppsala universitet Freds- Och Konfliktforskning
N/A / Link / Wallensteen , Peter / 2008

N/A / Link / Andersson , Catrine / 2009

Uppsala universitet Samhällsvetenskap
978-91-974783-3-5 / Link / Sölvell , Örjan / 2009

Uppsala universitet Samhällsvetenskap
9781553392255 / Link / Chen , Zhao / 2009

Large disulfide-stabilized proteoglycan complexes were previously shown to be synthesized by the epidermis of axolotl embryos during stages crucial to subepidermal migration of neural crest cells. We now show that the complexes contain PG-M/versican-like monomers in addition to some other component with low buoyant density. Metabolically 35S-labeled proteoglycans were extracted from epidermal explants and separated by size exclusion chromatography and density equilibrium gradient centrifugation. The complexes, which elute in the void volume on Sepharose CL-2B, were recovered at buoyant density 1.42 g/ml in CsCl gradients, whereas the monomer proteoglycans, which could only be liberated from the complexes by reduction, had a higher buoyant density (1.48 g/ml). The native complexes did not aggregate with hyaluronan. The purified complexes reacted with antibodies against a portion of a cloned PG-M/versican-like axolotl proteoglycan. These antibodies were found to stain the subepidermal matrix of axolotl embryos, suggesting that the proteoglycan complexes are encountered by neural crest cells during subepidermal migration. From Western blot analysis, the core protein of the PG-M/versican-like monomers was found to be of similar size ( approximately 500 kDa) as those of PG-M/versican variants of other species. Another chondroitin sulfate proteoglycan that was present in small amounts in the epidermal extracts was found to be distinctly different from the similarly sized PG-M/versican-like monomers.
N/A / Link / Stigson , Michael / 1997

Proteoglycans (PGs) synthesized by the epidermis during stages crucial to the subepidermal migration of neural crest cells in the trunk of the axolotl (Ambystoma mexicanum, Urodela, Amphibia) embryo were studied. The glycosaminoglycan chains were biosynthetically labeled with [35S]sulfate in vitro during a period corresponding to the onset of migration. After extraction with guanidine HCl, the radiolabeled PGs were separated according to size by molecular-sieve chromatography on Sepharose CL-2B under dissociative conditions. This resulted in the separation of high-molecular-weight PGs, which eluted in the void volume, and low-molecular-weight PGs, eluting in a broad peak with a mean Kav of 0.7. The large PGs were also found to elute in the void volume when chromatographed on a Sephacryl S-1000 column. The low-molecular-weight PGs contained heparan sulfate and chondroitin sulfate (CS) and were not further characterized. The glycosaminoglycan component of the high-molecular-weight PG was completely degraded by chondroitinase ABC, while a large portion was resistant to chondroitinase AC, indicating the presence of dermatan sulfate (DS). These CS/DS chains were of unusually large size (Mr approximately 150,000) as estimated by chromatography on Sepharose CL-4B, relating the elution position to hyaluronan standards. Moreover, the chains were found to have a lower surface charge density than standard CS, and may therefore be undersulfated. After reduction and alkylation the high-molecular-weight PGs were included on both Sepharose CL-2B and Sephacryl S-1000 columns, eluting at Kav 0.2 and 0.4, respectively. Hence, the high-molecular-weight material appears to consist of large PG complexes, stabilized by intermolecular disulfide bonds. A CS/DSPG of similar size as the reduced monomeric form of the high-molecular-weight PG was found in small amounts in the total extract of 35S-labeled material.
N/A / Link / Stigson , Michael / 1991

N/A / Link / Xue , Ming / 2009

N/A / Link / Du , Lin / 2008

Uppsala universitet Idé- O Lärdomshistoria
N/A / Link / Samuelsson , Joel / 2009

N/A / Link / Andersson , Staffan / 2007

Uppsala universitet Informationsteknik
978-1-4244-1538-0 / Link / Roberts , William / 2008

We reviewed the outcome in 10 idiopathic clubfeet in 7 patients treated with the Ilizarov external fixator (IEF) for persistent foot deformities after previous surgery. After follow-up of a median of 40 (25-56) months, 6 patients/parents were satisfied with the results and most of them reported better walking capacity and fewer problems finding shoes that fit. Severe equinus deformity was seen in 9/10 feet prior to treatment in the IEF and in no foot at follow-up. However, persistent reduction of ankle joint motion, limited walking capacity and intermittent pain were commonly found.
N/A / Link / Wallander , H / 1996

Uppsala universitet Pedagogik
9781412940689 / Link / Lundgren , Ulf / 2009

Uppsala universitet Pedagogik
N/A / Link / Lundgren , Ulf / 2008

Uppsala universitet Vårdvetenskap
The primary aim was to investigate the distress perceived by adolescents with cancer treated in paediatric oncology. In Study I, especially distressing events for children/adolescents with cancer were identified by interviews with children/adolescents/parents and nurses. Data were analysed with content analysis. A range of physical and emotional concerns was identified. Physical concerns are of a rather similar nature across age groups. Emotional concerns vary more between age groups. For children 8-12 years, emotional concerns are rather frequent. In Study II distressing and positive aspects related to some care situations for adolescents with cancer were identified by interviews with adolescents and nurses. Data were analysed with content analysis. A range of negative aspects, e.g. fear of alienation, fear of dying, altered appearance and physical concerns, as well as positive aspects, e.g. positive relations to staff and being well cared for were identified.The aspects of distress identified in Studies I and II formed the basis for a structured interview-guide, used in Studies III and IV. Adolescents, recently diagnosed with cancer, physicians and nurses were interviewed by telephone about distress, anxiety, depression and well-being experienced by the adolescents. Adolescent ratings of prevalence, levels and worst aspects of distress do not necessarily agree, however, worry missing school and mucositis are among those rated with the highest prevalence, levels and those perceived as the overall worst. The findings from Study IV demonstrate that physicians and nurses underestimate the distress caused by worry missing school and mucositis. The accuracy of physician and nurse ratings of physical distress is acceptable, however, this is not the case for psychosocial distress. It can be concluded that it is crucial to consider how questions are asked when interpreting the significance of the answers, and that action on adolescent problems in relation to cancer diagnosis and treatment need to rely on direct communication.
91-554-6176-X / Link / Hedström , Mariann / 2005