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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
151

Bis(4-chlorophenyl) sulfone and PCB methyl sulfone metabolites : Trends and chirality in the Baltic Sea environment

Norström, Karin January 2006 (has links)
The Baltic Sea was earlier identified as a highly polluted brackish water body and still is. The high concentrations of polychlorinated biphenyls (PCBs), p,p’-DDT and related compounds led to severe effects on several species in the Baltic region. However, the situation has improved significantly since the 1970’s resulting in lower exposures to a range of pollutants and healthier wildlife populations. Independent of this positive trend there are still new chemicals leaking into the Baltic Sea environment. The objective of this thesis is to improve the knowledge of sulfone containing compounds and pollutant metabolites in wildlife, with special interest in bis(4-chlorophenyl) sulfone (BCPS) distribution, temporal trend and exposure levels, and the methylsulfonyl-PCBs (MeSO2-PCBs). The latter are of particular interest for chiral MeSO2-PCBs. BCPS is used for the production of high temperature polymers and was detected as an environmental contaminant ten years ago. PCBs, p,p’-DDT and related compounds are still of scientific interest. BCPS is biomagnified and especially in the bird guillemot which has levels of up to 2000 ng BCPS/g fat compared to the grey seal with concentrations of about 60 ng/g fat. The seal levels are similar to the herring, the prey of the bird and seal, with concentrations of 30 ng BCPS/g fat. The guillemot concentration of BCPS has been similar over the last 30 years with a minimal, but significant, annual decline of 1.6%. The reason for the slow decline is not yet understood. Also MeSO2-PCBs and 3-MeSO2-DDE show a small decrease over time in guillemot egg (3 and 9%, respectively), which is less then for the parent compounds. This shows that the sulfone metabolites are more persistent than their precursors in the guillemot. Furthermore, all these sulfone containing compounds showed a specific retention to liver comparing different tissues in grey seal. The atropisomers of the chiral MeSO2-PCB were analysed in both the guillemot and the grey seal and showed to occur in a skewed relationship. This is particularly pronounced in seals where one atropisomer of each chiral congener is very dominating. The dominating atropisomers have been identified with an absolute R configuration, in both grey seal and guillemot. An enantioselective metabolism was indicated to occur when experimentally tested by CB-132 in rat. This thesis is stressing the high specificity in wildlife for one atropisomer in the pair of chiral PCB methyl sulfones being PCB metabolites, and the high BCPS concentrations in guillemot hatching in the Baltic proper.
152

Skattetillägg, straff och förhållandet till Europakonventionen

Karlgård, Anna January 2009 (has links)
I dagsläget kan enligt den svenska rättsordningen en skattskyldig på samma grund påföras skattetillägg och lagföras för någon form av skattebrott utan att dubbelbestraffning anses föreligga. Såväl den svenska lagstiftningen som Europeiska konventionen den 4 november 1950 om skydd för de mänskliga rättigheterna och de grundläggande friheterna innehåller förbud mot dubbelbestraffning. Under flera decennier har till Europadomstolen förts mål som behandlar dubbelbestraffning och domstolen har framarbetat flera metoder att använda vid bedömningen av om ett förfarande strider mot dubbelbestraffningsförbudet i Europakonventionen. Den 10 februari 2009 meddelade domstolen dom i målet Zolotukhin mot Ryssland. Domen meddelades i stor kammare och domstolen uttryckte att den såg ett behov av att förtydliga hur bedömningen skulle ske. I och med denna dom tog diskussionerna kring den svenska ordningens förenlighet med Europakonventionen fart. I Norge motsvarar sanktionssystem på skatteområdet i stor utsträckning det svenska. Regeringen har där lämnat ett förslag om förändring av lagstiftningen då Høyesterett funnit att den norska rättsordningen strider mot Europakonventionen. Mot denna bakgrund avser författaren att utreda huruvida den svenska rättsordningen på skatteområdet strider mot Europakonventionen samt om det finns ett behov av ny svensk lagstiftning och vilka huvuddrag denna i sådana fall skulle innehålla. Författarens slutsats är att rättsläget har förändrats i och med Zolotukhin-domen och att det, som framgår av domen, är huruvida de faktiska omständigheterna är identiska eller i det närmaste identiska som ska vara avgörande för bedömningen. Med anledning av detta anser författaren att det svenska sanktionssystemet på skatteområdet strider mot Europakonventionen och att det därmed finns ett behov av en ny lagstiftning på området. För att uppnå en rättsordning som är rättssäker och i enlighet med Europakonventionen samtidigt som påföljdernas straffmässiga och preventiva effekt upprätthålls anser författaren att utformningen av en ny lagstiftning bör utvecklas i likhet med det norska förslaget. Skatteverket ska, utifrån tydliga riktlinjer, bedöma huruvida rekvisiten för skattebrott är uppfyllda och, om det finner att så är fallet, överlämna ärendet till polisen för väckande av åtal. Om Skatteverket inte anser att det rör sig om grov vårdslöshet eller uppsåt, eller om domstolen eller polisen inte instämmer i bedömningen och återför ärendet till skattemyndigheten, kan skattetillägg påföras. Påförande av skattetillägg bör inte vara möjligt på enbart objektiva grunder, dock ska tolkningen av de subjektiva omständigheterna göras restriktivt.
153

Synthesis of ruthenium complexes having one or more N-heterocyclic carbene ligands supported on hybrid mesostructured silicas and their use in the hydrogenation of carbon dioxide

Baffert, Mathieu 30 September 2011 (has links) (PDF)
The goal of this PhD was to elaborate supported Ru-NHC catalytic materials based on hybrid organic-inorganic materials having imidazolium units perfectly distributed within a silica matrix. Passivation of these imidazolium materials followed by formation of NHC-carbene and reaction with [RuCl2(p-cymene)]2 provided these well-defined surface sites of general structures RuCl2(NHC)(L), where L was para-cymene (p-cymene) or THF depending on the reaction conditions, which could be further replaced by PMe3. These systems were then tested in the hydrogenation of CO2 in presence of amine to give formamides. The mono-NHC systems were highly active only in the presence of PMe3 ligands, but suffered from Ru leaching, evidencing the low stability of the NHC-Ru bond under the reaction conditions. On the other hand, dinuclear bis-NHC Ru systems were also developed, and they displayed much improved activity and stability in the hydrogenation of CO2 in the presence of PMe3 compared to the mono-NHC systems. This allowed the use of much higher reaction temperatures (200 °C) and provided heterogeneous catalysts with performances close to those obtained with the best homogeneous catalysts, Cl2Ru(dppe)2.
154

Charting New Territory in Bis(imino)pyridine Coordination Chemistry

Jurca, Titel 17 July 2012 (has links)
This work was initially launched to study the synthesis of low-valent group 13 compounds bearing the bis(imino)pyridine ligand framework. Since its inception, this project has grown beyond the boundaries of group 13 to include low valent tin, silver, and rhenium. Alongside the reports of novel coordination compounds, we utilized computational chemistry to uncover unprecedented interactions which challenge conventional concepts of bonding. Synthesis, characterization, and complimentary computational studies are presented herein. Chapter 1 presents a historical overview of the bis(imino)pyridine ligand as well as our synthetic methodology and characterization of new ligand variants we have contributed to the literature. Chapter 2 presents the synthesis of a series of In(I) and In(III) bis(imino)pyridine complexes with varied sterics. Ligand-metal interaction and effect of ligand steric bulk on complex stability, as well as computational studies highlighting weak covalent interactions will be discussed. Chapter 3 presents the synthesis of Ga(III) bis(imino)pyridine complexes. Reactivity with “GaI” synthon as well as varied-stoichiometry one-pot synthesis attempts to generate low valent Ga-bis(imino)pyridine complexes will be discussed. Chapter 4 presents the synthesis of a series of Tl(I) bis(imino)pyridine complexes with varied sterics analogous to the approach taken with indium(I). Unprecedented weak ligand-metal as well as Tl-arene interactions will be discussed. Chapter 5 presents the synthesis of a series of Sn(II) bis(imino)pyridine complexes with varied sterics and halide substituents. Preferential cation-anion pair formation and attempted reactivity will be discussed. Chapter 6 presents the synthesis of a series of Ag(I) bis(imino)pyridine complexes with varied sterics. Resulting ligand-metal interactions as well as reactivity towards Lewis basic donor ligands will be discussed. Chapter 7 presents the synthesis of first crystallographically authenticated examples of rhenium(I) pincer complexes utilizing the bis(imino)pyridine ligand. Chapter 8 presents a general conclusion to the work.
155

Osteoblast Behaviour on Injectable Biomaterials Intended for Augmentation of Vertebral Compression Fractures

Ramstedt, Sandra January 2007 (has links)
Biomaterials used for stabilization of compressed vertebraes due to osteoporosis, have mainly been based on resin materials, like PMMA (polymethyl methacrylate), but have recently expanded to consist of injectable ceramics, such as calcium-aluminate. In this in vitro study human osteoblast-like cells, MG-63, were cultured on three different injectable biomaterials based on: Ca-aluminate, Bis-GMA (bisphenol A-glycidylmethacrylate) and PMMA, to investigate the cellular response elicited by these materials. Cell proliferation was measured by the NucleoCounter® system, cell viability was investigated by LDH (lactate dehydrogenase) analysis, cell differentiation and mineralization was evaluated by mRNA gene expression of the osteoblastic markers: ALP (alkaline phosphatase), OC (osteocalcin) and COLL-I (collagen type I) by qPCR (quantitative polymerase chain reaction) analysis. Two control materials were used: TCP (tissue culture polystyrene, negative control) and PVC (polyvinyl chloride, positive control). The results showed that all the bone cement materials were non-toxic and biocompatible, i.e. they provided good cell viability and proliferation of the MG-63 cells. They are specific for bone cells, since they expressed high values of the osteoblast-specific differentiation markers, and are thus promising as injectable bone cement materials. Among the bone cements, Xeraspine appears to be the most biocompatible material for bone cells. It is followed by Cortoss and then Vertebroplastic.
156

Ne bis in idem : A comparative study of the interpretation of the principle in Sweden and Norway concerning tax surcharge and tax fraud

Karlsson, Sandra January 2011 (has links)
The ne bis in idem-principle was founded in 1984 and is found in article 4 of the seventh additional protocol of the Convention for the Protection of Human Rights and Fundamental Freedoms. The interpretation of the principle has been uncertain, which resulted in a harmonization of all previous case law on the subject in the Zolotukhin case. The case concerns a Russian citizen who brought his girlfriend onto a Russian military base while being drunk. This action resulted in an administrative proceeding and a criminal proceeding. The Swedish and Norwegian tax systems concerning tax surcharge and tax fraud are very alike and both countries adapt a dual court system. The differences concerning the interpretation are found in four cases from 2009 and 2010, two from the Norwegian Supreme Court, one from the Swedish Supreme Administrative Court and one from the Swedish Supreme Court. Even though there are similarities in the argumentations in the cases there are also different approaches concerning how to interpret the principle. The Norwegian Supreme Court bases its judgements, especially in the second one after the Zolotukhin case, on the prerequisites established by the European Court of Human Rights and the purpose of the principle. The Swedish Supreme Court and the Swedish Supreme Administrative Court bases the judgements on previous case law and refers to the uncertain judicial area and affirms that there is room for interpretation for the national courts. Even though the argumentation in the judgements differ the national Supreme Courts reach the same answer to the question whether the tax systems are a breach of the ne bis in idem-principle. None of the courts finds that the national tax systems are an infringement of the ne bis in idem-principle.
157

Hydroxy cruciforms and bis(hydroxystyryl)benzenes: synthesis, structure, and photophysical properties of novel π-systems

McGrier, Psaras Lamar 15 June 2010 (has links)
This thesis examines the synthesis, photophysical properties, and sensory responses of hydroxy-substituted 1,4-distyryl-2,5-bis(arylethynyl)benzenes (Cruciforms, XFs). These two-dimensional cross-conjugated materials possess spatially separated frontier molecular orbitals (FMOs). This spatial separation allows the HOMO and LUMO to be addressed independently by analytes, which leads to significant changes in their absorption and emission. These properties allow XFs to be utilized for the detection of various analytes. These studies highlight the benefits of utilizing XFs for the development of advanced functional solid state materials for sensory applications.
158

Skattetillägg, straff och förhållandet till Europakonventionen

Karlgård, Anna January 2009 (has links)
<p>I dagsläget kan enligt den svenska rättsordningen en skattskyldig på samma grund påföras skattetillägg och lagföras för någon form av skattebrott utan att dubbelbestraffning anses föreligga. Såväl den svenska lagstiftningen som Europeiska konventionen den 4 november 1950 om skydd för de mänskliga rättigheterna och de grundläggande friheterna innehåller förbud mot dubbelbestraffning. Under flera decennier har till Europadomstolen förts mål som behandlar dubbelbestraffning och domstolen har framarbetat flera metoder att använda vid bedömningen av om ett förfarande strider mot dubbelbestraffningsförbudet i Europakonventionen. Den 10 februari 2009 meddelade domstolen dom i målet Zolotukhin mot Ryssland. Domen meddelades i stor kammare och domstolen uttryckte att den såg ett behov av att förtydliga hur bedömningen skulle ske. I och med denna dom tog diskussionerna kring den svenska ordningens förenlighet med Europakonventionen fart. I Norge motsvarar sanktionssystem på skatteområdet i stor utsträckning det svenska. Regeringen har där lämnat ett förslag om förändring av lagstiftningen då Høyesterett funnit att den norska rättsordningen strider mot Europakonventionen. Mot denna bakgrund avser författaren att utreda huruvida den svenska rättsordningen på skatteområdet strider mot Europakonventionen samt om det finns ett behov av ny svensk lagstiftning och vilka huvuddrag denna i sådana fall skulle innehålla.</p><p>Författarens slutsats är att rättsläget har förändrats i och med Zolotukhin-domen och att det, som framgår av domen, är huruvida de faktiska omständigheterna är identiska eller i det närmaste identiska som ska vara avgörande för bedömningen. Med anledning av detta anser författaren att det svenska sanktionssystemet på skatteområdet strider mot Europakonventionen och att det därmed finns ett behov av en ny lagstiftning på området. För att uppnå en rättsordning som är rättssäker och i enlighet med Europakonventionen samtidigt som påföljdernas straffmässiga och preventiva effekt upprätthålls anser författaren att utformningen av en ny lagstiftning bör utvecklas i likhet med det norska förslaget. Skatteverket ska, utifrån tydliga riktlinjer, bedöma huruvida rekvisiten för skattebrott är uppfyllda och, om det finner att så är fallet, överlämna ärendet till polisen för väckande av åtal. Om Skatteverket inte anser att det rör sig om grov vårdslöshet eller uppsåt, eller om domstolen eller polisen inte instämmer i bedömningen och återför ärendet till skattemyndigheten, kan skattetillägg påföras. Påförande av skattetillägg bör inte vara möjligt på enbart objektiva grunder, dock ska tolkningen av de subjektiva omständigheterna göras restriktivt.</p>
159

Osteoblast Behaviour on Injectable Biomaterials Intended for Augmentation of Vertebral Compression Fractures

Ramstedt, Sandra January 2007 (has links)
<p>Biomaterials used for stabilization of compressed vertebraes due to osteoporosis, have mainly been based on resin materials, like PMMA (polymethyl methacrylate), but have recently expanded to consist of injectable ceramics, such as calcium-aluminate. In this in vitro study human osteoblast-like cells, MG-63, were cultured on three different injectable biomaterials based on: Ca-aluminate, Bis-GMA (bisphenol A-glycidylmethacrylate) and PMMA, to investigate the cellular response elicited by these materials. Cell proliferation was measured by the NucleoCounter® system, cell viability was investigated by LDH (lactate dehydrogenase) analysis, cell differentiation and mineralization was evaluated by mRNA gene expression of the osteoblastic markers: ALP (alkaline phosphatase), OC (osteocalcin) and COLL-I (collagen type I) by qPCR (quantitative polymerase chain reaction) analysis. Two control materials were used: TCP (tissue culture polystyrene, negative control) and PVC (polyvinyl chloride, positive control). The results showed that all the bone cement materials were non-toxic and biocompatible, i.e. they provided good cell viability and proliferation of the MG-63 cells. They are specific for bone cells, since they expressed high values of the osteoblast-specific differentiation markers, and are thus promising as injectable bone cement materials. Among the bone cements, Xeraspine appears to be the most biocompatible material for bone cells. It is followed by Cortoss and then Vertebroplastic.</p>
160

Formation and Characterization of Polymerized Supported Phospholipid Bilayers and the in vitro Interactions of Macrophages and Fibroblasts.

Page, Jonathan Michael 01 August 2010 (has links)
Planar supported, polymerized phospholipid bilayers (PPBs) composed of 1,2-bis[10-(2’,4’-hexadienoyloxy)decanoyl]-sn-glycero-3-phosphocholine (bis-SorbPC or BSPC) were generated by a redox polymerization method. The PPBs were supported by a silicon substrate. The PPBs were characterized and tested for uniformity and stability under physiological conditions. The PPBs were analyzed in vitro with murine derived cells that are pertinent to the host response. Cellular attachment and phenotypic changes in RAW 264.7 macrophages and NIH 3T3 fibroblasts were investigated on PPBs and compared to bare silicon controls. Fluorescent and SEM images were used to observe cellular attachment and changes in cellular behavior. The PPBs showed much lower cellular adhesion for both cell lines than bare silicon controls. Of the cells that attached to the PPBs, a very low percentage showed the same morphological expressions as seen on the controls. The hypothesis generated from this work is that defects in the PPBs mediated the cellular attachment and morphological changes that were observed. Finally, a layer-by-layer (LbL) deposition of a poly(acrylic acid) (PAA) and poly(N-vinylpyrrolidone) (PNVP) alternating bilayer was attempted as a proof of concept for future modification of this system.

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