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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.
91

Laboratory and Field Characterization of Micro-surfacing Mix Bond Strength

Talha, Sk Abu 23 September 2019 (has links)
No description available.
92

Proteomické rozlišení srsti psích plemen / Proteomic differentiation of hairs of different dog breeds

Humpoláková, Karin January 2021 (has links)
The goal of my thesis was to find out whether it is possible to distinguish among individual dog breeds from the protein analysis of their fur. This knowledge could be used, for example, in forensic science. In this work, there was also a comparison of the similarity of dog breeds with a wolf, which was domesticated and is considered as an ancestor of the dog. For this study, the hair of three representatives of sixteen dog breeds was collected. To analyse these samples enzyme cleavage was used a trypsin, and mass spectra were obtained by MALDI- TOF MS (Matrix-Assisted Laser Desorption/Ionization - Time of Flight Mass Spectrometry) and LC/MS-MS (Liquid Chromatography with Tandem Mass Spectrometry) methods. The obtained data were evaluated by the PCA (Principal Component Analysis) and LDA (Linear Discriminant Analysis) method. It was found, that individual dog breeds cannot be distinguished using both methods. KEYWORDS proteomics, coat, dog, breeds, mass spectrometry
93

Sequence Analysis of PMEL17 as Candidate Gene for Causing Rat-Tail Syndrome in Cattle

Hecht, Benjamin C. 18 July 2006 (has links) (PDF)
Congenital hypotrichosis in cattle is commonly referred to as "rat-tail" syndrome and is characterized by a dilution of black coat color and morphological changes to the hair shaft and tail switch. Two loci are involved in the inheritance of the rat-tail phenotype, the "extension locus" (MC1R) and an unknown locus. In order to express the rat-tail phenotype the animal must inherit at least one black allele at MC1R and be heterozygous at the unknown locus. The rat-tail locus was previously mapped to an 8.7 cM region of Bos Taurus autosome (BTA) 5. Pmel17 is known to be involved in the expression of pigmentation and maps to the same region of BTA5 as the rat-tail locus. Cattle from a population segregating for the rat-tail syndrome were sequenced at Pmel17 in order to identify putative causative mutations. Two mutations were detected, a three base pair (bp) deletion in exon 1 at codon 18 removing a leucine residue, and a single nucleotide polymorphism (SNP) at codon 612 resulting in an amino acid substitution (A?E). The 3-bp deletion in exon 1 of Pmel17 is in 100% concordance with the rat-tail phenotype in this research population and may be causative of the rat-tail phenotype.
94

Effects Of Bond Coat Surface Preparation On Thermal Cycling Lifetime And Failure Characteristics Of Thermal Barrier Coatings

Liu, Jing 01 January 2004 (has links)
Thermal barrier coatings (TBCs) have been widely used in gas turbine engines to protect the underlying metal from high operating temperature so as to improve the durability of the components and enhance the engine efficiency. However, since the TBCs always operate in a demanding high-temperature environment of aircraft and industrial gas-turbine engines, a better understanding of this complex system is required to improve the durability and reliability. The objective of this study is to investigate the effects of surface modification for the NiCoCrAlY bond coats on the thermal cycling lifetime and failure characteristics of TBCs. Parameters of modification for the bond coats included as-sprayed, barrel-finished, hand-polished and pre-oxidation heat treatment at 1100[degrees]C in P=10O2-8 atm up to 4 hours, carried out prior to the electron beam physical vapor deposition (EB-PVD) of ZrO2-7wt% Y2O3 (7YSZ) ceramic topcoat. The resulting characteristics of the bond coat and the thermally grown oxide (TGO) scale were initially documented by surface roughness, phase constituents of the TGO scale, and residual stress of the TGO scale. The thermal cycling test consisted of 10-minute heat-up to 1121°C, 40-minute hold at 1121°C, and 10-minute forced air-quench. As-coated and thermally-cycled TBCs were characterized by optical profilometry (OPM), photo-stimulated luminescence spectroscopy (PSLS), optical microscopy, scanning electron microscopy (SEM) equipped with energy dispersive spectroscopy (EDS), and scanning/transmission electron microscopy (TEM/STEM) equipped with high angle annular dark field (HAADF) and X-ray energy dispersive spectroscopy (XEDS). TBC specimens for TEM/STEM analysis were prepared by focused ion beam (FIB) in-situ lift-out (INLO) technique. Superior thermal cycling lifetime was observed for TBCs with as-sprayed bond coats regardless of pre-oxidation heat treatment, and TBCs with hand-polished bond coats only after pre-oxidation heat treatment. With pre-oxidation heat treatment, relative photostimulated luminescence intensity of the equilibrium α-Al2O3 increased. Thus, the improvement in TBC lifetime can be correlated with an increase in the amount of α-Al2O3 in the TGO scale, given a specific surface modification/roughness. The lifetime improvement due to pre-oxidation was particularly significant to TBCs with smooth hand-polished bond coats and negligible for TBCs with rough as-sprayed bond coats. Spallation-fracture paths depended on the lifetime of TBCs. Premature spallation of TBCs occurred at the interface between the YSZ and TGO. Longer durability can be achieved by restricting the fracture paths to the TGO/bond coat interface. Small particulate phase observed through the TGO scale was identified as Y2O3 (cubic) by diffraction analysis on TEM. While small addition of Y in the NiCoCrAlY bond coat helps the adhesion of the TGO scale, excessive alloying can lead to deleterious effects.
95

Identification Of Proteins Regulating Vldl Sorting Into The Vldl Transport Vesicle (vtv) And Involved In The Biogenesis Of The Vtv

Tiwari, Samata 01 January 2013 (has links)
Increased secretion of very low-density lipoprotein (VLDL), a triglyceride-rich lipoprotein, by the liver causes hypertriglyceridemia, which is a major risk factor for the development of atherosclerosis. The rate of VLDL-secretion from the liver is determined by its controlled transport from the endoplasmic reticulum (ER) to the Golgi. The ER-to-Golgi transport of newly synthesized VLDL is a complex multi-step process and is mediated by the VLDL transport vesicle (VTV). Once a nascent VLDL particle is synthesized in the lumen of the ER, it triggers the process of VTV-biogenesis and this process requires coat complex II (COPII) proteins that mediate the formation of classical protein transport vesicles (PTV). Even though, both VTV and PTV bud off the same ER at the same time and require the same COPII proteins, their cargos and sizes are different. The VTV specifically exports VLDL to the Golgi and excludes hepatic secretory proteins such as albumin and the size of the VTV is larger (~ 100 -120 nm) than PTV to accommodate VLDL-sized particles. These observations indicate (i) the existence of a sorting mechanism at the level of the ER; and (ii) the involvement of proteins in addition to COPII components. This doctoral thesis is focused on identification of proteins regulating VLDL sorting into the VTV and involved in the biogenesis of the VTV. In order to identify proteins present exclusively in VTV, we have characterized the proteome of VTV, which suggest CideB (cell death-inducing DFF45-like effector b) and SVIP (small VCP/P97 interacting protein) as candidates, present in VTV but excluded from PTV. We further confirmed the finding by performing co-immunoprecipitation studies and confocal microscopy studies. CideB, a 26-kDa protein was found to interact with apolipoprotein iv B100 (apoB 100), the structural protein of VLDL. Moreover, CideB interacts with two of the COPII components, Sar1 and Sec24. VTV generation was examined after blocking CideB by specific antibodies and by silencing CideB in rat primary hepatocytes. Knockdown of CideB in primary hepatocytes showed significant reduction in VTV generation, however, CideB was concentrated in VTV as compared with the ER suggesting its functional role in the sorting of VLDL into the VTV. SVIP, a small (~ 9-kDa) protein was found to interact with Sar1, a COPII component that initiates the budding of vesicles from ER membrane. SVIP has sites for myristoylation and we found increased recruitment of SVIP on ER membrane upon myristic acid (MA) treatment. Sar1 that lacks sites for myristoylation also is recruited more on ER upon myristoylation indicating that SVIP promotes Sar1 recruitment on ER. Additionally, our data suggest that Sar1 interacts with SVIP and forms a multimer that facilitates the biogenesis of VTV. Interestingly, silencing of SVIP reduced the VTV generation significantly. Conversely, incubation with MA increased the VTV budding, suggesting recruitment of SVIP on ER surface facilitates the VTV budding. We conclude that SVIP recruits Sar1 on ER membrane and makes an intricate COPII coat leading to the formation of a large vesicle, the VTV. Overall, the data presented in this thesis, determines the role of CideB and SVIP in regulating VLDL sorting and VTV biogenesis.
96

Assessing the Distribution and Impact of <I>Bean pod mottle virus</I> (BPMV) as a Re-emerging Virus, and <I>Soybean mosaic virus </I>(SMV) in Soybean Grown in Virginia

Mackasmiel, Lucas A. 10 September 2004 (has links)
<I>Bean pod mottle virus </I>(BPMV, Genus <I>Comovirus</I>, Family: <I>Comoviridae</I>)is an important virus in soybean (<I>Glycine max</I> (L.) Merrill), causing quality and yield loss due to seed coat mottling and seed weight reduction. Although BPMV has been known in Virginia since 1958 and has always been regarded as causing negligible losses, its impact is changing as BPMV incidence has increased in many soybean growing areas of Virginia and the USA in general. From 1997 to 2001, a total of five BPMV isolates (V-W1, V-W2, V-S98-1, V-S98-15 and V-S01-10) were collected in Virginia and characterized. In this study, the effects of these isolates were studied, alone or with Soybean mosaic virus (SMV, Genus Potyvirus, Family Potyviridae) strain SMV G1, and isolates S98-51 and S98-52, on selected soybean cultivars. Individual isolates of BPMV showed variable symptom severity, and resulted in yield loss of between 40.4 to 58.1%, while SMV caused 23.7% in the most severe interactions. Up to 100% yield loss was realized from double inoculations of selected BPMV and SMV isolates, BPMV V-S98-1 + SMV S98-52 and BPMV S98-15 + SMV S98-52 on Hutcheson and Hutcheson Roundup Ready&#174; (BC5) soybeans, respectively. Time of inoculation, a critical factor in the impact of many virus diseases, affected seed coat mottling in four cultivars and seed weight in two cultivars, in tests with four BPMV isolates and three stages of soybean development. All BPMV isolates inoculated to plants at vegetative stage V1-V3 severely increased seed coat mottling and reduced seed weight than those inoculated at V4-V6 and reproductive stage R1-R3. Seedlings grown from non-mottled seeds germinated more uniformly had fewer thin-stemmed seedlings and grew faster than those grown from mottled seeds. Inoculation of various cultivars and breeding lines showed that there was no correlation between the severity of virus-induced foliar symptoms, relative accumulation of SMV, and extent of seed coat mottling. Thus, by avoiding the presence of BPMV at an early growth stage through proper timing of planting to avoid vectors, proper cultural practices like weed control, use of SMV free seeds, and chemical control, it is possible to greatly improve seed quality and reduce yield losses in soybean. / Ph. D.
97

Effect of varying optimization parameters on optimization by guided evolutionary simulated annealing (GESA) using a tablet film coat as an example formulation

Plumb, A.P., Rowe, Raymond C., York, Peter, Doherty, C. January 2003 (has links)
The purpose of this study was to investigate the effect of varying optimization parameters on the proposed optimum of a tablet coating formulation requiring minimization of crack velocity and maximization of film opacity. An artificial neural network (ANN) comprising six input and two output nodes separated by a single hidden layer of five nodes was trained using 100 pseudo-randomly distributed records and optimized by guided evolutionary simulated annealing (GESA). GESA was unable to identify a formulation that satisfied both a crack velocity of 0 m s¿1 and a film opacity of 100% due to conflict centred on the response of the properties to variation in pigment particle size. Constraining film thickness exacerbated the property conflict. By adjusting property weights (i.e. the relative importance of each property), GESA was able to propose formulations that were either crack resistant or that were fully opaque. Reducing the stringency of the performance criteria (crack velocity >0 m s¿1, film opacity <100%) enabled GESA to propose optima that met or exceeded the looser targets. Under these conditions, starting GESA from different locations within model space resulted in the proposal of different optima. Therefore, application of loose targets resulted in the identification of an optimal zone within which all formulations satisfied these less stringent performance criteria. It is concluded that application of the most stringent performance criteria and selection of appropriate property weights is necessary for unequivocal identification of the true optimum. A strategy for optimization experiments is proposed.
98

Genetic basis of species differentiation in Sulawesi macaques, Indonesia / インドネシアのスラウェシ島固有のマカクにおける種分化の遺伝的基盤

Yan, Xiaochan 26 September 2022 (has links)
付記する学位プログラム名: 霊長類学・ワイルドライフサイエンス・リーディング大学院 / 京都大学 / 新制・課程博士 / 博士(理学) / 甲第24185号 / 理博第4876号 / 新制||理||1698(附属図書館) / 京都大学大学院理学研究科生物科学専攻 / (主査)教授 今井 啓雄, 教授 古賀 章彦, 准教授 Huffman Michael Alan / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM
99

Effect of Ta, Hf, and Si on the High Humidity Oxidation Resistance of MCrAlY Bond Coat Materials

Katerina Luiza, Monea 18 January 2024 (has links)
The continued focus to include high hydrogen fuels such as Syngas in aircraft operation to reduce emissions and increase engine efficiency has led to an ongoing investigation into bond coat materials capable of withstanding unfavourable oxidation in high temperature humid environments. The increased presence of water in the engine exhaust leads to increased oxygen activity in the hot section of the engine. In this work, four commercially available MCrAlY bond coat materials were oxidized in high temperature environments with various humidities to understand the behaviours of different reactive element inclusions in resisting high temperature oxidation. Oxidation tests were done at 0%, 18%, and 33% water by volume at 1100C in a 1atm environment to simulate conditions expected in engines using high hydrogen fuels. Oxidation was done for 2h and 20h to observe transient oxide formation behaviour. The surfaces and cross sections of the specimens were examined using SEM and EDS analysis, along with XRD analysis. The progression of surface oxides, TGO thickness, and element depletion zones were observed. Two opposing mechanisms are observed: the upward diffusion of metal cations to the free surface and the inward diffusion of oxygen to the alloy. The presence of water is shown to increase internal oxidation of the bond coat alloy and delay the formation of a protective alumina TGO. Tantalum inclusion in the alloy composition is shown to produce the most stable alumina TGO with the least internal oxidation after 20h exposure in 33% H2O (%vol); the most hostile oxidation environment tested.
100

The Use of Polyaspartic Gel Coats for the Improvement of Wind Turbine Composite Blades

Eisemon, Kristine Ellen 23 October 2009 (has links)
No description available.

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