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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.
31

Determining cross-reactivity between human and mouse tissue using mono-specific antibodies

Monazzami, Avin January 2007 (has links)
ABSTRACT The Swedish Human Proteome Resource (HPR) is a project about mapping of human genes and proteins. It aims to describe the function and distribution of all human genes and corresponding proteins, using in-house produced antibodies and tissue microarrays (TMA) for enzyme based immunohistochemistry. The mono-specific antibodies are used for immunostaining of human tissue. Specific predicted antigens named Protein Epitope Signature Tag (PrEST) are needed to produce mono-specific antibodies. PrEST are produced using recombinant technology from predicted genes and used as immunogens to produce (mono-specific) antibodies in rabbits. In this study, 84 mono-specific antibodies with known specificity to human proteins were used for immunohistochemical analysis of mouse tissues to determine the cross reactivity between mouse and human. For 6 of the 84 antibodies the results differed between mouse and human tissue. A comparison between the PrEST used with the mouse proteome using database search programs showed homologies that were less than 100% in these six cases. Thus, future studies on cross reactivity will focus on how to increase the accuracy in its prediction at the in silico stage of the experiment.
32

A Design of Speech Recognition System for Three-word and Four-word Mandarin Phrases

Sue, Ji-sin 10 September 2006 (has links)
In this thesis, a three-word and four-word Mandarin phrases speech recognition system is developed. This system contains two recordings of twenty-four thousand three-word phrases and twenty-two thousand four-word phrases in the database. And it applies MFCC, mono-syllable HMM¡¦s and speech-text alignment scheme to select the initial phrase candidates. A wavelet transform based vowel segmentation technique and a Mandarin pitch identification method is then followed to increase the phrase correct identification rate and obtain the final answer. Experimental results indicate that 92% and 96% correct rates can be achieved for three-word and four-word phrases recognition problems respectively, under the conditions that the first recording of this database is used for training and the second one is for testing. For the speaker-dependent case, the correct phrase can be found within 1 second, using a PC with Intel Celeron 2.4 GHz CPU and RedHat Linux 9.0 Operation System.
33

Molecular level interactions of large area 2D materials

Na, Seung Ryul 10 August 2015 (has links)
Two-dimensional materials such as self-assembled monolayers (SAMs), graphene, etc. are candidate materials for improving the performance of microelectronics components and MEMS/NEMS devices. In view of their relatively large in-plane dimensions, surface forces are likely to dominate their behavior. The purpose of the current work was to extract not only the adhesion energy (or steady state fracture toughness) but also the traction-separation relation associated with interactions between various two-dimensional materials and substrates. In particular, interactions between SAMs terminated by carboxyl and diamine (COOH/NMe2) groups, hydroxylated silicon surfaces, graphene and silicon, graphene and its seed copper and graphene and epoxy over large areas was considered. Traction-separation relations, which are a continuum description of such molecular interactions, were determined by a direct method, which makes use of measurements of crack tip opening displacements; an inverse approach where the key parameters are extracted by comparing measured global parameters with finite element solutions and a hybrid approach in which the direct method was supplemented by finite element analysis. Furthermore, the surface free energy of graphene was measured by contact angle measurements. The most striking observation across all the interactions that were considered is that the interaction ranges were much larger than those attributed to van der Waals forces. While van der Waals models might have been at play between graphene and its seed copper foil and graphene and epoxy, the adhesion energies were surprisingly high. This coupled with the long interaction range suggests that roughness effects modulated the basic force field. Interactions between graphene and silicon and hydroxylated silicon surfaces may have been due to capillary and/or electrostatic again possibly modulated by roughness. The interactions between COOH and NMe2 SAMs became stronger under vacuum, which may have induced chemical bonding, and tougher under mixed-mode loading. / text
34

Phosphorus Fertilizer Rate Effect on Alfalfa Yield and Soil Test P, Buckeye, 2014

Ottman, Mike, Rovey, Jason, Mostafa, Ayman, Burayu, Worku 06 1900 (has links)
10 pp. / Phosphorus is the primary fertilizer nutrient needed by alfalfa in Arizona. The objective of this study is to determine the effect of P fertilizer rate on alfalfa yield and soil test P. A phosphorus fertilizer rate study was conducted with alfalfa in Buckeye, AZ where 11-52-0 was applied at 0, 200, 400, and 800 lb fertilizer/acre in February, 2014 after the first cutting. Alfalfa hay yield was increased by phosphorus fertilizer application up to the cutting on July 30, but not thereafter. No differences in yield were found among the fertilizer rates of 200,400, and 800 lb 11-52-0/acre. Soil test phosphorus increased directly proportional to fertilizer rate, but eventually decreased close to deficient levels 3-5 months after fertilizer application. It is not known if additional fertilizer applications throughout the season would increase yield. Fertilizer rates higher than 200 lb 11-52-0/acre were not beneficial under the conditions of this study.
35

The chemical evolution of shallow groundwater along the northeastern shoreline of Mono Lake, California

Connell, Tracy L. January 1993 (has links)
Thesis (M.S.)--University of California, Santa Cruz, 1993. / Typescript. Includes bibliographical references (leaves 193-197).
36

Fibras nervosas e melanócitos no queloide: estudo morfológico / Nerve fibers and melanocytes in keloid: a morphological study

Hochman, Bernardo [UNIFESP] January 2005 (has links) (PDF)
Made available in DSpace on 2015-12-06T23:06:38Z (GMT). No. of bitstreams: 0 Previous issue date: 2005 / Introdução: A patogênese do quelóide é desconhecida. Apesar da inervação cutânea participar da cicatrização, existe uma lacuna na literatura relativa ao sistema nervoso cutâneo no quelóide. Objetivo: Quantificar fibras nervosas e melanócitos no quelóide, bem como avaliar a atividade melanogênica. Métodos: Compararam-se amostras de quelóide e de pele adjacente da região torácica de 27 pacientes não-brancas. As fibras nervosas e os melanócitos foram corados por imuno-histoquímica, pela reação à proteína S-100. A quantificação das fibras nervosas dérmicas, e das células melanocíticas epiteliais, foi realizada por contagem direta em cada tecido. A profundidade da fibra nervosa mais superficial, em relação à camada granulosa, foi mensurada por régua histológica. Os dados obtidos também foram analisados em função do tempo de evolução das lesões. A atividade melanogênica foi quantificada mediante reação imunohistoquímica, por anticorpo anti-tirosinase. Resultados: As amostras de quelóide apresentaram quantidade maior de fibras nervosas (p < 0,001), em comparação com o tecido cutâneo adjacente à lesão. A fibra nervosa mais superficial no quelóide estava a uma profundidade maior que na pele (p < 0,001). A quantidade de melanócitos nas amostras de quelóide foi menor em relação às de pele (p < 0,001), da mesma forma quanto à tirosinase (p < 0,001). Com o tempo evolutivo das lesões, não houve associação estatística dos resultados das fibras nervosas e melanócitos. Conclusão: O quelóide apresenta maior quantidade de fibras nervosas dérmicas e numa profundidade maior em relação à pele. A quantidade de melanócitos e de tirosinase é menor no quelóide que na pele. / Background: Keloid pathogenesis is still unknown. In spite of the cutaneous innervation taking part of scarring, there is a gap in the literature on cutaneous nervous system in keloid. Purpose: To quantify both nerve fibers and melanocytes in keloid, as well as to evaluate the melanogenic activity. Methods: Both keloid and adjacent skin specimens from the chest region of 27 non-white subjects were compared. Nerve fibers and melanocytes underwent immunohistochemical dyeing by S-100 protein reaction. The quantification of dermal nerve fibers and epithelial melanocytic cells was carried out by direct counting of each tissue. Depth of the most superficial nervous fiber, when compared to the granular layer was measured through a histological meter. Data obtained were also analyzed as a function of the lesions development time. Melanogenic activity was quantified through immunohistochemical reaction by anti-tyrosinase antibody. Results: Keloid specimens showed a higher quantity of nerve fibers (p<0.001) when compared to lesion-adjacent cutaneous tissues. Keloid most superficial nervous fiber was deeper than the ones of the skin (p<0.001). The amount of melanocytes in the keloid specimens was lower than the amount in the skin (p<0.001), as well as tyrosinase (p<0.001). Statistically significant association with lesions development time of nerve fibers and melanocytes results was not found. Conclusion: Keloid presents a higher quantity of dermal nerve fibers which are most deeply located than they occur in the skin. Melanocytes and tyrosinase amounts are lower in keloid than in the skin. / BV UNIFESP: Teses e dissertações
37

Modification and Performance Evaluation of a Mono-valve Engine

Behrens, Justin William 01 August 2011 (has links)
AN ABSTRACT OF THE THESIS OF Justin W. Behrens, for the Master of Science degree in Mechanical Engineering, presented on June 24, 2011 at Southern Illinois University Carbondale. TITLE: MODIFICATION AND PERFORMANCE EVALUATION OF A MONO-VALVE ENGINE MAJOR PROFESSOR: Dr. Suri Rajan A four-stroke engine utilizing one tappet valve for both the intake and exhaust gas exchange processes has been built and evaluated. The engine operates under its own power, but has a reduced power capacity than the conventional 2-valve engine. The reduction in power is traced to higher than expected amounts of exhaust gases flowing back into the intake system. Design changes to the cylinder head will fix the back flow problems, but the future capacity of mono-valve engine technology cannot be estimated. The back flow of exhaust gases increases the exhaust gas recirculation (EGR) rate and deteriorates combustion. Intake pressure data shows the mono-valve engine requires an advanced intake valve closing (IVC) time to prevent back flow of charge air. A single actuation camshaft with advanced IVC was tested in the mono-valve engine, and was found to improve exhaust scavenging at TDC and nearly eliminated all charge air back flow at IVC. The optimum IVC timing is shown to be approximately 30 crank angle degrees after BDC. The mono-valve cylinder head utilizes a rotary valve positioned above the tappet valve. The open spaces inside the rotary valve and between the rotary valve and tappet valve represent a common volume that needs to be reduced in order to reduce the base EGR rate. Multiple rotary valve configurations were tested, and the size of the common volume was found to have no effect on back flow but a direct effect on the EGR rate and engine performance. The position of the rotary valve with respect to crank angle has a direct effect on the scavenging process. Optimum scavenging occurs when the intake port is opened just after TDC.
38

A model of the hydrothermal system at Casa Diablo in Long Valley, California, based on resistivity profiles and soil mercury analyses

Arfstrom, John David 22 July 1993 (has links)
A description and model of the near-surface hydrothermal system at Casa Diablo, with its implications for the larger-scale hydrothermal system of Long Valley, California, is presented. The data include resistivity profiles with penetrations to three different depth ranges, and analyses of inorganic mercury concentrations in 144 soil samples taken over a 1.3 by 1.7 km area. Analyses of the data together with the mapping of active surface hydrothermal features (fumaroles, mudpots, etc.), has revealed that the relationship between the hydrothermal system, surface hydrothermal activity, and mercury anomalies is strongly controlled by faults and topography. There are, however, more subtle factors responsible for the location of many active and anomalous zones such as fractures, zones of high permeability, and interactions between hydrothermal and cooler groundwater. In addition, the near-surface location of the upwelling from the deep hydrothermal reservoir, which supplies the geothermal power plants at Casa Diablo and the numerous hot pools in the caldera with hydrothermal water, has been detected. The data indicate that after upwelling the hydrothermal water flows eastward at shallow depth for at least 2 km and probably continues another 10 km to the east, all the way to Lake Crowley.
39

Constraints on dark matter models using a fast simulation of the ATLAS detector

Taylor, Samantha H. 13 August 2021 (has links)
Data collected at the LHC are analyzed by the ATLAS collaboration for evidence of dark matter. In this thesis, a fast simulation of the ATLAS detector response using the Delphes software is assessed for dark matter models with a leptonically decaying Z boson and a pair of dark matter particles in the final state. Limits for the Two Higgs Doublet plus pseudoscalar dark matter model are obtained using simplified systematics, and found to be nearly indistinguishable to limits obtained using the more complex standard ATLAS analysis. / Graduate
40

The effects of principals' workloads in Limpopo multi-grade primary schools on learners' academic performance

Kgomo, Phuti Thompson January 2017 (has links)
This study was conducted in multi-grade primary schools located in Limpopo Province, Capricorn District, Bochum Cluster. The main purpose of the study was to analyse the effects of the principals’ workloads on learners’ academic performance in multi-grade primary schools in Limpopo Province. Twelve schools with the most multi-grade classes were qualitatively sampled from four circuits of Bochum Cluster (Bochum East, Bochum West, Maleboho Central and Maleboho East) as the target for the study. Multi-grade schools are characterised by low learner enrolment. The departmental model of allocating teachers to schools allocates posts according to the number of learners in a school regardless of grades. The school principal is therefore compelled to teach full-time and carry out other related responsibilities such as administration, professional duties and extra-mural activities. Both qualitative and quantitative approaches were employed to achieve the research goals. The study was based on the research question How do principals’ workloads affect learners’ academic performance in multi-grade primary schools in the Capricorn district, Limpopo Province? The study findings, based on interviews, observations and documents analysis have revealed that there are some managerial, leadership, curriculum, teaching and administrative challenges that principals in multi-grade schools are faced with. These challenges collectively contribute to principals’ heavy workload that eventually affect learners’ performance negatively. The researcher therefore concluded that the principals’ workload in multi-grade primary schools have a negative impact on learners’ performance. / Dissertation (MEd)--University of Pretoria, 2017. / Education Management and Policy Studies / MEd / Unrestricted

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