<p>Combustion of kerosene propellants often deposits soot on chamber walls. These deposits act as a thermal barrier and can significantly affect the analysis of cooling systems. This is especially vital for reusable engines since the accumulated soot deposit can make the wall heat flux vary between every firing. This dissertation discusses a computational and experimental effort to understand the main drivers of these soot deposits. The computational approach employs the Method of Moments with Interpolative Closure (MOMIC) model to predict soot particle dynamics; Brownian and thermophoretic diffusion for particle transport to the chamber surface; and the Hydrogen-Abstraction-Acetylene-Addition (HACA) mechanism for soot surface growth. These models were incorporated in a 1D plug flow reactor. Two-dimensional axisymmetric reacting CFD simulations were also run to understand the flow field influence on the near wall gas phase chemistry. Simultaneously, a fuel rich kerosene and gaseous oxygen experiment was developed and fired to obtain soot deposit thickness measurements for model comparison. The results show the reduced order plug flow model can satisfactorily predict the soot thickness and that thermophoresis is the dominant deposition mechanism. However, though the model can predict deposit mass trends, it underpredicts the absolute values for some conditions and may need an additional mechanism. </p>

Knowledge of how intermolecular interactions of amyloidogenic proteins cause protein aggregation and how those interactions are affected by sequence and solution conditions is essential to our understanding of the onset of many degenerative diseases. Of particular interest is the aggregation of the amyloid-β (Aβ) peptide, linked to Alzheimer's disease, and the aggregation of the Sup35 yeast prion peptide, which resembles the mammalian prion protein (PrP) linked to spongiform encephalothopies. To facilitate the study of these important peptides, experimentalists have identified small peptide congeners of the full-length proteins that exhibit amyloidogenic behavior, including the KLVFFAE sequence of the Aβ protein, and the GNNQQNY sequence of Sup35. Reverse micelles provide an important environment for the study of protein folding and aggregation. In a reverse micelle, it is possible to observe the effects that confinement and water activity, believed to play a critical role in an in vivo cellular environment, have on protein folding, misfolding, and aggregation. We employed molecular dynamics simulations of reverse micelles as well as peptides encapsulated in reverse micelles in order to characterize the reverse micelle environment and identify fundamental principles that inform how sequence and solution environment influence protein aggregation. The peptides studied include the alanine-rich peptide AKA2 as well as the amyloidogenic KLVFFAE and GNNQQNY peptide fragments. The results of these studies suggest that substantial fluctuations in reverse micelle shape away from an idealized spherical geometry enables significant interaction between peptides and the surfactant interface. Analysis these results, including evaluation of water dynamics and calculated IR spectra of the amide I vibration of the peptides, indicate that our model of the reverse micelle is a robust one which captures essential features of this complex system. Moreover, our studies provide critical insight into the complex role played by a heterogeneous cellular environment in the earliest stages of protein aggregation and amyloid formation.

The Giles Creek and upper Chandler formations crop out in the northeastern Amadeus Basin from the north flank of Ross River syncline south to the Pillar Range, and from the nose of Ooraminna anticline east to the Simpson Desert. 'Twenty-four sections of the Giles Creek and nineteen sections of the upper Chandler were measured by the author in this area. The Giles Creek lies disconformably above the upper Chandler Formation and conformably below the Shannon Formation. The upper Chandler is conformably underlain by the lower Chandler throughout the area except at Ross River Gorge and Wallaby No. 1 well. There the upper Chandler overlies the Todd River Dolomite. The Giles Creek and upper Chandler consist of interbedded carbonates, terrigenous-rich carbonates, and mudrocks. Terrigenous-rich carbonates and mudrocks comprise over half of the volume of the Giles Creek at most locations in the area. Lime mudstones and cryptalgalaminated boundstones with dorral stromatolites are common in the Giles Creek. The Phillipson and Northern Facies of the Giles Creek are locally fossiliferous at the base. Ooids are present at the top of the Southern and Phillipson Facies of the Giles Creek at most locations. Anhydrite is present in the carbonates and mudrocks of the Giles Creek at Dingo No. 1 and Wallaby No. 1 wells. Gypsum is present in dolostones of the Giles Creek at Wallaby No. 1 well. Oncolite grainstones and boundstones, crystalgalaminated boundstones, and birdseye-rich lime mudstones are common in the upper Chandler. The mudrocks of the Giles Creek and upper Chandler are composed of quartz, K-feldspar, illite, muscovite, biotite, kaolinite, smectite, plagioclase, and anhydrite, with minor amounts of limonite, hematite, vermiculite, chlorite, and zircon. Calcite and dolamite cement the mudrocks. Acid-insoluble residues of the carbonates are comprised of the above noncarbonate minerals, organic matter, pyrophyllite, and witherite. The size and amount of terrigenous material in the Giles Creek increases to the west-southwest, which indicates that the terrigenous sediments were derived from a source area in that direction. Sediments of the Giles Creek and upper Chandler were dolomitized by seepage-reflux of a hypersaline brine. Lateral and vertical variations in the amount of dolanite are inversely related to the amount of terrigenous material, and indicate that permeability of the sediments was a controlling factor in the distribution of dolomite in the Giles Creek. Sediments of the Giles Creek and upper Chandler accumulated on shoals, in shoal-margin lagoons, on tidal flats, and in intracoastal lagoons. Shallow, open-shelf deposits are also present at the base of the Giles Creek at Ross River Gorge. Cyclicity in the sediments of the Giles Creek was caused by lateral shifts in the position of the tidal flats and intracoastal lagoons during continual subsidence of the basin. Both the Giles Creek and upper Chandler -were deposited during major regressions of the sea. Lateral relations of lithofacies in the Giles Creek indicate that the area was bounded by deeper water to the north and south during the Middle Cambrian. Differential subsidence of the basin resulted in deposition of greater thicknesses of Giles Creek sediments in the Phillipson Pound and Ross River-Fergusson syncline areas. Differential subsidence in the Phillipson Pound area was partially offset by salt-induced growth of Ooraminna, Tood River-Windmill, Brumby, and Teresa anticlines. Facies relations and lateral variations in thickness of the Giles Creek suggest that the amount of offset on the Rodinga and Carrel Flat faults is minor, perhaps on the order of 1 to 2 kilometers at most. Initial carbonate sediments of the Giles Creek and upper Chandler were altered by syngenetic inversion of aragonite to calcite, recrystallization of calcite, precipitation of pyrite, and replacer-rent of calcite by dolomite; anagenetic silicification, compaction, and fracturing; and epigenetic oxidation, precipitation of calcite, dedolomitization, and silicification. Post-depositional changes in the terrigenous sediments include syngenetic oxidation, alteration of clay minerals, precipitation of silica, and dolomitization.

Forest Service grazing permits for cattle and sheep were analyzed. A livestock and land resource summary was completed for each non-temporary permit reported on the 98 forests in the twelve western states. The economic feasibility of private rangeland improvements to offset public land grazing in Rich County, Utah, was analyzed in the second section of this thesis. The internal rate of return for various projects was computed. The internal rate of return was used as an indicator of the economic feasibility to ranchers. These estimates were made on a county basis and do not apply to any particular ranch situation.

京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第18071号 / 理博第3949号 / 新制||理||1569(附属図書館) / 30929 / 京都大学大学院理学研究科物理学・宇宙物理学専攻 / (主査)教授 永江 知文, 准教授 成木 恵, 教授 鶴 剛 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM

Recent studies suggest that factor (F) XII, which is dispensable for hemostasis, is important for thrombus stabilization and growth. Therefore, FXIIa inhibition may attenuate thrombosis without disrupting hemostasis. FXII activation is stimulated by polyanions such as polyphosphates released from activated platelets, and nucleic acids released by cells. Previously, we showed that histidine-rich glycoprotein (HRG) binds FXIIa with high affinity, inhibits FXII autoactivation and FXIIa-mediated activation of FXI, and attenuates ferric chloride-induced arterial thrombosis in mice. Thus, HRG has the capacity to downregulate the contact pathway in vitro and in vivo. This thesis aimed to identify the complementary binding domains of HRG and FXIIa, and to further explore the anticoagulants effects of HRG on FXIIa-mediated contact activation. We hypothesized that FXIIa binds to the zinc-binding histidine-rich region (HRR) of HRG and that HRG binds to the non-catalytic heavy chain of FXIIa to exert its anticoagulant activities on FXIIa-mediated contact activation. We have localized the complementary binding sites of HRG and FXIIa to be within the HRR domain of HRG and NH2-FNII-EGF1 (NFE) domains of FXIIa. Moreover, we show that the HRR binds to short chain polyphosphate with high affinity, suggesting a dynamic complex between HRG, FXIIa, and polyphosphate (polyP) on activated platelets. We provide evidence for two potential mechanisms through which HRG modulates the contact system. These include by 1) inhibiting FXIIa activity and 2) attenuating the procoagulant effect of polyanions, such as polyP on FXIIa-mediated reactions. Indeed, we show that the interaction of HRG with FXIIa and polyphosphate is predominantly mediated by the HRR domain and that HRR analogs have the capacity to recapitulate the anticoagulant effects of HRG in purified and plasma systems. Therefore, by modulating FXIIa-mediated contact pathway reactions, like HRG, HRR analogs may attenuate thrombosis without disrupting hemostasis. / Thesis / Doctor of Philosophy (Medical Science)

In this thesis, in investigation of various diffusion couple designs is discussed with the aim of enhancing the interaction between the three diffusive flow. Experimental investigation of the theoretical predictions his been carried out for infinite and finite couple boundary conditions. The four independent diffusion coefficients in the copper-rich copper-zinc-tin system have been measured it two temperatures for the dilute composition range. / Thesis / Master of Science (MS)

微小管結合タンパク質の1つであるタウは、神経細胞の軸索に特異的に局在している。タウの軸索局在化分子機序を解明するために、外因性タウを神経細胞の発達初期に一時的に発現させ、軸索特異的に局在させる方法を構築した。この方法を用い、proline rich region 2 (PRR2)がタウの軸索局在化に重要であること、PRR2のリン酸化が軸索への移動に関与することを示唆した。またこの系の確立は局在や細胞内動態などの検討を行うことを可能にした。 / Microtubule-associated protein tau localizes specifically to neuronal axons. In order to elucidate the molecular mechanism of the axon localization of tau, we constructed an expression system for axon specific localization of exogenous tau in immature neurons in culture. Using this system, it suggested that the proline rich region 2 (PRR2) and phosphorylation of PRR2, which contains important phosphorylation sites, is critical for the localization. In the future, this experimental system will contribute greatly to the study of tau in normal and in the pathology of Alzheimer's disease. / 博士(理学) / Doctor of Philosophy in Science / 同志社大学 / Doshisha University

In this thesis, a theoretical study of certain properties of the diffusion coefficient matrix in a multicomponent system has been carried out. The ratio of the off-diagonal diffusion coefficient to the on-diagonal diffusion coefficient in a dilute ternary substitutional system has been evaluated theoretically. The effect of the second solute gradient on the diffusivity of the first one in a ternary substitutional solid solution has been experimentally determined using the neutron activation analysis technique. / Thesis / Master of Engineering (MEngr)

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