No description available.

The proposed human intestinal absorption prediction model is applied to over 900 pharmaceuticals and has about 82.5% true prediction power. This study will provide a screening tool that can differentiate well absorbed and poorly absorbed drugs in the early stage of drug discovery and development. This model is based on fundamental physicochemical properties and can be applied to virtual compounds. The maximum well-absorbed dose (i.e., the maximum dose that will be more than 50 percent absorbed) calculated using this model can be utilized as a guideline for drug design, synthesis, and pre-clinical studies.

Denna uppsats har behandlat hur svenskamerikaner förhöll sig till och placerade sig i de amerikanska rasliga och etniska hierarkierna genom att undersöka den svenskamerikanska pressen i Chicago mellan 1890 – 1920. Hypotesen för uppsatsen var att det fanns ett motstånd motsammansmältningen på grund av två skäl: Dels att de inte ville ge upp sin identitet som svenskamerikaner, dels att de inte ville dras ned från deras gynnsamma position i hierarkierna. Med hjälp av studier kring vithet och ras samt svenskamerikaners etnicitetsskapande har uppsatsen argumenterat för att den svenskamerikanska pressen kunde hävda den egna immigrantgruppen som en önskvärd del i det amerikanska samhället. Detta genom upprätthållandet av en färglinje gentemot den icke-vita befolkningen, fragmentisering av vithet samt kritiserandet av sammansmältningar mellan svenskamerikaner och andra grupper i samhället. Hypotesen kunde bekräftades då förlusten av svenskamerikanernas etniska och rasliga identitet vid en eventuellsammansmältning kunde resultera i en lägre gynnsam position i hierarkierna.

This work involved an investigation into the mechanisms governing the reduction of material in the solids bed of the Ifcon® process. Thermo gravimetric analyses were done to investigate the influence of various operational parameters on the rate of solid state reduction. The experiments were modeled, and model predictions were compared to experimental results. Kinetic data was analised and the reduction rate constants were calculated. The rate constants were used as inputs to a model, which describes the reduction behaviour and temperature profile in a composite solids bed (similar to that in the Ifcon® process). High temperature reduction- and melting tests were done in an 150 kW induction furnace, to simulate final reduction in a solids bed. The temperature profile through the solids bed was measured and results were compared to model predictions. Finally the extent to which solid state reduction occurs in the solids bed was estimated as a function of production rate. / Dissertation (MEng (Metallurgical Engineering))--University of Pretoria, 2008. / Materials Science and Metallurgical Engineering / unrestricted

Understanding U-series isotopic disequilibria of partially melted crust is integral for determining the effect that crustal assimilation has on the U-series signature of magmas. In this work, U, Th and Ba (as a proxy for Ra) elemental abundances were gathered on the quenched glass in partially melted crustal xenoliths of granitic composition using microbeam techniques. The crustal xenoliths, which are found in basaltic lava, from Mirador Volcano in Chile, are old, and can be assumed to be at secular equilibrium, whereas melting occurred during eruption of Mirador in 1979. A comparison of the ratios Ba/Th and U/Th in the partial melts with those of the whole rock reveal how much fractionation has occurred during partial melting. Different ratios of U, Th and Ba compared to the whole rock substantiate fractionation via partial melting. Thus, assimilation of partial melts of crust can play a role in U-series isotopic disequilibria.

Additive Manufacturing (AM), commonly known as 3D printing is a production method that utilises repeated addition of layers in order to produce a final shape. AM utilises less raw material and does not have drawbacks such as tool wear and material wastage as seen in conventional machining. However, they do have drawbacks such as poor surface and internal defects.  A common practice in AM is the fabrication of contour and bulk region using separate parameters.  The aim of this project was to study the effects of various process parameters on the contour properties. The process parameters considered were scanning speed, beam current and focus offset. The Nickel alloy Inconel 718 was utilised in Electron Beam Melting (EBM) to fabricate the test specimen. The samples used in this project were in an as-built condition which was priorly subjected to tensile testing for a different project. The tests performed in this project are hardness testing and microstructural investigation about grains, precipitates and the various defects.  The test results helped to understand the effect of various process parameters on the hardness and microstructure of the samples. The samples with lower scanning speed had higher hardness and lesser lack of fusion than samples with higher speed. In the case of varying beam current, the samples with higher beam current had higher hardness values and fewer lack of fusions. Similarly, the effects of varying two or more process parameters were also studied and their findings recorded. The microstructure consisted of a large number of shrinkage porosities in the bulk and contour regions. The presence of Niobium rich precipitates at grain boundaries and the grain structure for various process parameters were identified and recorded.

[pt] Um dos grandes fatores motivadores das operações de fusões e aquisições é a expectativa de criação de valor para as empresas envolvidas. Este trabalho tem por objetivo avaliar esta expectativa por parte dos acionistas por ocasião do anúncio de tais operações. Para isso foram analisadas 20 operações, destacadas no período de 2003 a 2011 no mercado brasileiro, através da metodologia de estudo de evento. Neste estudo foram medidos os retornos anormais ocorridos nas ações de emissão das empresas adquirentes, com a utilização das cotações destas ações na BMEFBOVESPA, assumindo que as expectativas de criação de valor são imediatamente incorporadas aos preços dos ativos, logo após a disponibilização da informação sobre a operação de fusão ou aquisição. / [en] One of the most important reasons for Mergers and Acquisitions deals is the expectation of value creation for the companies involved. The objective of this research is to evaluate this expectation by the shareholders by the time of the announcement of the deal. In order to do that, 40 deals were analyzed, spanning the period from 2003 to 2011 in the Brazilian market, using the event study methodology. During this work, the abnormal returns obtained by the acquiring companies’ shares were measured, using data from the Brazilian stock exchange BMEFBOVESPA, considering the premise that the expectations of value creation are immediately added to the assets’ prices, after the announcement of the M&A deals. For the whole sample considered no statistically significant abnormal returns were detected, although in a few specific deals they have been observed, both positive and negative.

Les komatiites sont des roches volcaniques ultrabasiques caractéristiques de l'Archéen et du Protérozoïque. Nous présentons ici une étude de la pétrogénèse des komatiites de la ceinture de Barberton en Afrique du Sud. Celle-ci comprend un modèle de fusion original bâti à partir de la constatation expérimentale qu'à très forte profondeur (P>13GPa), les liquides komatiitiques sont plus denses que la péridotite solide et donc ne peuvent pas s'échapper de leur source. Nous proposons que la fusion des sources des komatiites de Barberton ait commencée à une pression supérieure à 13GPa dans le manteau mais que les liquides produits soient restés retenus dans les sources jusqu'à ce que celles-ci n'aient dépassé, au cours de leur remonté, la limite de densité à laquelle le liquide devient moins dense que le résidu solide (à ~13GPa). Alors, les liquides auraient commencé à quitter leur source, d'abord doucement, puis de plus en plus vite alors que la différence de densité entre le liquide et le résidu solide s'accroissait. Les komatiites appauvries en Al, qui sont les plus abondantes à Barberton, auraient été produites par les premiers liquides qui ont quitté la source peu après le franchissement de la limite de densité. Les liquides qui quittèrent ensuite cette même source à moins forte pression, auraient formé les komatiites enrichies en Al. Les komatiites non-appauvries en Al auraient été produites par le même mécanisme mais par des sources de température potentielle plus forte. Une étude parallèle des trois systèmes isotopiques Sm-Nd, Lu-Hf et Re-Os nous a permis de contraindre l'histoire chimique des sources de komatiites de Barberton. Les systèmes Sm-Nd et Lu-Hf indiquent des sources appauvries et le système Re-Os une source chondritique. Nous proposons que les sources des komatiites aient été appauvries par l'extraction de croûte, mais qu'ensuite, leur composition en Re et Os aient été ramenées à leur valeur chondritique par le dernier épisode massif d‟accrétion de la Terre : « le vernis tardif ». / Komatiites are ultrabasic volcanic rocks characteristic of the Archean and Proterozoic eras. In this study, we investigate the petrogenesis of the komatiites of the Barberton greenstone belt in South Africa. We present an original melting model developed on the experimental observation that, at great depths (P>13GPa), komatiitic liquids are denser than solid peridotite, and therefore cannot escape their source. We propose that the fusion of the sources of Barberton komatiites began at pressures greater than 13GPa in the mantle but that the liquids produced were retained in the sources until they crossed, during their ascent, the density limit at which the liquid becomes less dense than the residue (at ~13GPa). Then, the liquids would have started to escape their source, slowly at first, and faster and faster as the density contrast between liquid and solid residue increased. Al-depleted komatiites, which are the most common type in the Barberton belt, were produced as the first liquids that escaped the source soon after they crossed the density limit. The liquids that later escaped the same source at shallower depth, formed Al-enriched komatiites. Al-undepleted komatiites were produced by the same mechanism but from hotter sources. From complementary studies of the three isotopic systems Sm-Nd, Lu-Hf and Re-Os, we constrained the chemical history of the sources of Barberton komatiites. The Sm-Nd and Lu-Hf systems indicate depleted sources whereas the Re-Os system indicates a chondritic source. We propose that the sources of the komatiites had become depleted by the extraction of early crust, and that their compositions in Re and Os were then reset to their chondritic value by contamination by material from the last massive accretion stage of the Earth: “the late veneer”.

京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第22370号 / 医博第4611号 / 新制||医||1043(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 別所 和久, 教授 戸口田 淳也, 教授 妻木 範行 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

Selective laser melting (SLM) is a new and rapidly developing manufacturing method for producing full-density, geometrically complex metal parts. The SLM process is time and cost effective for small-scale production; however, wide-spread adoption of this technique is severely limited by residual stresses that can cause large deformations and in-process build failures. The issues associated with residual stress accumulation are most apparent in parts with overhanging features. Due to the complexity of the SLM process, the accumulation of residual stresses is difficult to assess a priori. The deformations and in-process failures caused by residual stress accumulation often lead to an expensive and time consuming iterative manufacturing process. To aid in the development of general SLM design guidelines for overhanging features, the effect of varying two support structure design parameters on residual stress accumulation were investigated. A part-scale thermo-mechanical finite element model was implemented using Diablo, a multi-physics finite element code developed by Lawrence Livermore National Laboratory (LLNL), and trends observed in the model were validated experimentally. By comparing the distribution and magnitude of residual stresses, it was determined that reducing cooling rate gradients in overhanging features reduces the resulting residual stresses. Additionally, it was shown that volume effective material properties can be used to reduce computational costs in computational models of the SLM process.