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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.
231

The functional characterization of the SnRK1 protein complex in hybrid poplar

Lam, Kimberley SW 11 1900 (has links)
The sucrose-nonfermenting-1 related kinase 1 (SnRK1) protein complex is a heterotrimeric serine/threonine protein kinase complex conserved in eukaryotes that acts as a regulator of carbon metabolism and energy homeostasis. The objective of this study was to determine if the SnRK1 protein complex has a role in the nitrogen response and during dormancy acquisition in poplar. Gene expression profiling of the PtdSnRK1, PtdAKINbeta, and PtdAKINgamma gene family members was carried out using a robust qRT-PCR assay. A subset of these genes showed modified expression patterns under differential nitrogen availability and during dormancy acquisition, suggesting that SnRK1 complexes comprised of specific subunits may be involved in the regulation of the response to nitrogen and during dormancy acquisition. The regulatory subunits PtdAKINbeta1.1, PtdAKINgamma1.1 and PtdAKINgamma2.3 were often identified using principal component analysis as significantly responsible for distinguishing treatments from one another and therefore merit further study. / Plant Biology
232

礫浜斜面上の流速場と漂砂移動機構に関する研究

馬, 賢鎬, MA, Hyun-Ho, 水谷, 法美, MIZUTANI, Norimi, 江口, 周, EGUCHI, Shu 05 1900 (has links)
No description available.
233

Research and Development of Low-Profile, Small Footprint Antennas for VHF-UHF Range Applications

Olaode, Olusola January 2012 (has links)
<p>Efficient, but low-profile and small-footprint antennas for VHF-UHF range applications remains an ongoing work. VHF range spans approximately 54 - 88 MHz while UHF roughly ranges from 174 - 890 MHz. The inverse relationship between the physical length and resonant frequency of an antenna, which is a measure of its operating frequency range, is well known. A direct correlation between an antenna's physical length and radiation efficiency has also been established. Therefore, a combination of these constraints complicates the design of low-frequency antennas that have small physical size but with enough radiation resistance to be an efficient radiator when connected to a source having a comparable resistance. Given the frequency bands above, their corresponding wavelengths will be: 3.4-5.5 m (VHF) and 0.3-1.7 m (UHF). The length of an antenna operating at these wavelengths would need to be electrically-small i.e. a fraction of wavelength given size constraints for applications such as defense or commercial mobile communication equipment. As a consequence, the radiation resistance of the antenna, which is a function of its radiation efficiency, is greatly reduced. In other words, the input impedance or radiation impedance (assuming negligible ohmic losses in the antenna structure) features a small resistive component and a large capacitive component, causing reflections of most of the incident power to the antenna. Highly-reactive antennas are not desired for most transmitters and receivers. Therefore, the radiation resistance of an antenna must be increased by increasing its electrical length while simultaneously maintaining a low profile and footprint. This aim can be achieved by configuring the antenna to excite a resonance at, or very close to a desired operating frequency. An approach that I will explore in this dissertation is to exploit the broadband characteristics of meander-line and helical (or "spiral") antennas typically applied in the microwave frequency range to the UHF-VHF range. I will also propose novel antenna geometries that combine spiral and meander-line properties and analyze their performance. These antennas offer significant size reductions; for example, a bowtie meander dipole antenna studied yielded a height reduction of 55% at 64 MHz relative to a half-wave dipole antenna of the same resonant frequency. In addition, I will present a set of equations developed for predicting the fundamental resonant frequency and radiation resistance of meander-line antennas.</p> / Dissertation
234

Form and function of the Waihao-Wainono barrier, South Canterbury.

Stapleton, Joanne Maree January 2005 (has links)
The mixed sand and gravel barrier beaches located on the South Island's East Coast are formed predominantly of Greywacke, eroded from the mountains, and transported via the major river systems. These barriers act as the interface between the South Pacific Ocean and the surrounding hinterland. In times of high energy coastal events, breaching is common. This thesis examines the form and function of the Waihao-Wainono barrier, a section of the coastline situated north of the Waitaki River. Breaches along this part of the barrier are frequent and several have rendered the surrounding farmland unusable for several years due to the effects of saltwater inundation. There is some concern among the local community as to exactly why the barrier breaches at certain locations and not others, making land planning and management a difficult task for farmers. Several of the local landowners believe that since the construction of the Waitaki Dam in 1935, a significant decrease in sediment size along the barrier has occurred. It is also thought that the barrier form has experienced substantial change. Through the use of physical techniques used in the field of coastal science, 17 sites along the Waihao-Wainono barrier were studied. Excavations were carried out, surface and substrate profiles recorded and sediment samples collected from the surface. sub-surface and substrate of the barrier. Analysis of the barrier form and barrier volume concluded that the past breach sites consisted of steeper lower foreshore slopes than the non-breach sites, and at two sites, the substrate was not reached. Breach areas display the greatest barrier volume of all the study sites, which is contrary to belief. In relation to the surface sediments, the majority of barrier profiles displayed the distinct mean grain size cross shore zonation, characteristic of mixed sand and gravel beaches. The best and most consistent surface sorting was also identified as being a characteristic of the breach sites. The sediment size is not shown to have drastically reduced over the thirty year sampling period as was perceived by the local community. Within the sub-surface of the barrier, the sediments displayed chaotic sizes and generally poorly sorted material. Several of the breach sites contained a distinct change in sediment size between the coarser surface layer and the finer layer located immediately below. This layering of coarse and fine sized sediments leads to differences in permeability within the barrier, which is thought to be a major factor in why these sites have breached. Resulting from these findings, a group of characteristics of breach sites was formed and several predictions made as to where the barrier may breach in the near future.
235

Global Behavior Of Finite Energy Solutions To The Focusing Nonlinear Schr&ouml;dinger Equation In d Dimension

January 2011 (has links)
abstract: Nonlinear dispersive equations model nonlinear waves in a wide range of physical and mathematics contexts. They reinforce or dissipate effects of linear dispersion and nonlinear interactions, and thus, may be of a focusing or defocusing nature. The nonlinear Schrödinger equation or NLS is an example of such equations. It appears as a model in hydrodynamics, nonlinear optics, quantum condensates, heat pulses in solids and various other nonlinear instability phenomena. In mathematics, one of the interests is to look at the wave interaction: waves propagation with different speeds and/or different directions produces either small perturbations comparable with linear behavior, or creates solitary waves, or even leads to singular solutions. This dissertation studies the global behavior of finite energy solutions to the $d$-dimensional focusing NLS equation, $i partial _t u+Delta u+ |u|^{p-1}u=0, $ with initial data $u_0in H^1,; x in Rn$; the nonlinearity power $p$ and the dimension $d$ are chosen so that the scaling index $s=frac{d}{2}-frac{2}{p-1}$ is between 0 and 1, thus, the NLS is mass-supercritical $(s>0)$ and energy-subcritical $(s<1).$ For solutions with $ME[u_0]<1$ ($ME[u_0]$ stands for an invariant and conserved quantity in terms of the mass and energy of $u_0$), a sharp threshold for scattering and blowup is given. Namely, if the renormalized gradient $g_u$ of a solution $u$ to NLS is initially less than 1, i.e., $g_u(0)<1,$ then the solution exists globally in time and scatters in $H^1$ (approaches some linear Schr"odinger evolution as $ttopminfty$); if the renormalized gradient $g_u(0)>1,$ then the solution exhibits a blowup behavior, that is, either a finite time blowup occurs, or there is a divergence of $H^1$ norm in infinite time. This work generalizes the results for the 3d cubic NLS obtained in a series of papers by Holmer-Roudenko and Duyckaerts-Holmer-Roudenko with the key ingredients, the concentration compactness and localized variance, developed in the context of the energy-critical NLS and Nonlinear Wave equations by Kenig and Merle. One of the difficulties is fractional powers of nonlinearities which are overcome by considering Besov-Strichartz estimates and various fractional differentiation rules. / Dissertation/Thesis / Ph.D. Mathematics 2011
236

The Effect of Managerial Reputation on Corporate Tax Avoidance

Kim, Jin Wook, Kim, Jin Wook January 2012 (has links)
Prior literature suggests that tax avoidance is an effective way to enhance firm value. However, there appears to be considerable cross-sectional variation in tax avoidance, and it is not clear why some firms do not take full advantage of the tax avoidance opportunities being used by others. This study examines whether managerial reputation, as proxied by high-profile awards to top managers, is helpful in explaining corporate tax avoidance. The empirical results show that, relative to a matched control group, firms managed by a celebrity manager have significantly higher cash and GAAP effective tax rates in the three year period following the manager's first award than preceding the award. This result is consistent with the conjecture that celebrity managers, for fear of being labeled as "poor citizens," engage in less tax avoidance once they have an established reputation.
237

Localized Proton Magnetic Resonance Spectroscopy of Mouse Brain In Vivo at High Magnetic Field Strength

Abaei Tafresh, Alireza 13 May 2013 (has links)
No description available.
238

Rep-Index : uma abordagem abrangente e adaptável para identificar reputação acadêmica / Rep-Index : a comprehensive and adaptable approach to identify academic reputation

Cervi, Cristiano Roberto January 2013 (has links)
A tarefa de avaliar a produção científica de um pesquisador é fortemente baseada na análise de seu currículo. É o que fazem, por exemplo, as agências de fomento à pesquisa e desenvolvimento ou comissões de avaliação, quando necessitam considerar a produção científica dos pesquisadores no processo de concessão de bolsas e auxílios, na seleção de consultores e membros de comitês, na aprovação de projetos ou simplesmente para avaliar o conceito de um programa de pós-graduação. Nesse contexto, a modelagem de perfis de pesquisadores é tarefa fundamental, especialmente quando se quer avaliar a reputação dos pesquisadores. Isto pode ocorrer por meio de um processo de análise da trajetória de toda a carreira científica do pesquisador. Tal processo envolve não somente aspectos relacionados a artigos ou livros publicados, mas também por outros elementos inerentes à atividade de um pesquisador, como orientações de trabalhos de mestrado e de doutorado; participação em defesas de mestrado e de doutorado; trabalhos apresentados em conferências; participação em projetos de pesquisa, inserção internacional, dentre outros. O objetivo deste trabalho é especificar um modelo de perfil de pesquisadores (Rep- Model) e uma métrica para medir reputação acadêmica (Rep-Index). O processo de modelagem do perfil envolve a definição de quais informações são relevantes para a especificação do perfil e as apresenta por meio de 18 elementos e 5 categorias. O processo para medir a reputação do pesquisador é definido por uma métrica que gera um índice. Esse índice é calculado mediante a utilização dos elementos constantes no perfil do pesquisador. Para avaliar a abordagem proposta na tese, diversos experimentos foram realizados. Os experimentos envolveram a avaliação dos elementos do Rep-Model por meio de análise de correlação e por algoritmos de mineração de dados. O Rep-Index também foi avaliado e correlacionado com duas métricas amplamente utilizadas na comunidade científica, o h-index e o g-index. Como baseline, foram utilizados todos os pesquisadores do CNPq das áreas de Ciência da Computação, Economia e Odontologia. O trabalho desenvolvido nesta tese está inserido no contexto da identificação da reputação de pesquisadores no âmbito acadêmico. A abordagem desta tese tem como premissa ser abrangente e adaptável, pois envolve a vida científica do pesquisador construída ao longo de sua carreira científica e pode ser utilizada em diferentes áreas e em diferentes contextos. / The task of evaluating the scientific production of a researcher is based strongly on the analysis of their curriculum. It's what makes the agencies for research support or evaluation committees, when they need to consider the scientific production of researchers in the process of awarding grants and aid in the selection of consultants and committee members in approving projects or simply to assess the concept of a program graduate. In that context, the modeling of profiles of researchers is fundamental task especially when one wants to evaluate the reputation of the researchers. This can occur by means of a process of analysis of the trajectory of all the scientific career of the researcher. Such process involves not only aspects related to papers or books, but also other elements inherent in the activity of a researcher, as orientations of master’s degree and doctorate; participation in defense of master's and doctoral degrees; papers presented in conferences, participation in research projects, international integration, among others. This proposal specifies a profile template for researchers (Rep-Model) and a metric to measure academic reputation (Rep-Index). The profile modeling process involves define which information is relevant to the specification of the profile and shows through 18 elements and 5 categories. The process for measuring researcher's reputation is defined by a metric that generates an index. This index is calculated by using the information contained in the profile of the researcher. To evaluate the approach proposed in the thesis, extensive experiments were conducted. The experiments involved the evaluation of Rep-Model by means of correlation analysis and data mining algorithms. The Rep-Index was also evaluated and correlated with two metrics widely used in the scientific community, the h-index and gindex. As a baseline, all of CNPq researchers in the areas of Computer Science, Economics and Dentistry were used. The work in this thesis is set in the context of identifying the reputation of researchers within the academic sphere. The approach of this thesis is premised be comprehensive and adaptable, because it involves the life science researcher built throughout his scientific career and can be used in different research areas and in different contexts.
239

Fyziologické parametry ovcí plemene Suffolk v chovu v lokalitě Soběslav / Physiological parameters Suffolk breed of sheep breeding in Soběslav

TOMEČKOVÁ, Andrea January 2014 (has links)
The aim of the thesis was the evaluation of commercial properties, physiological state and selected blood parameters in sheep suffolk breed with focus on monitoring increases, blood parameters and coprological examination which prooved parasitological settlement. Monitoring was conducted in 2013 and early 2014 when 17 ewes and 16 lambs were observed. For thesis purpose two samples were made on 25.3.2013 and 14.10.2013. Several elevated values have been detected among which were glucose, urea, total protein, albumin, 1 and 2 globulin and partially cholesterol. ß globulin was below the physiological range, globulin was initially below the physiological range, but in the second sampling was above the physiological range. Decreased values were observed in case of calcium concentration in blood plasma. The parasitological findings prooved presence of coccidia Eimeria and gastrointestinal nematodes.
240

Caracterização topográfica e estrutural de filmes poliméricos provenientes de acetileno (C2H2) depositados a plasma sobre substratos lisos e rugosos

Teixeira, Ana Paula Gonçalves da Cruz [UNESP] 11 1900 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:25:30Z (GMT). No. of bitstreams: 0 Previous issue date: 2003-11Bitstream added on 2014-06-13T20:53:27Z : No. of bitstreams: 1 teixeira_apgc_me_guara.pdf: 1933388 bytes, checksum: a65434c8c77296c8a4c1caf57b057917 (MD5) / Filmes poliméricos obtidos ou processados a plasma têm sido objeto de muita pesquisa, devido às suas características peculiares que os tornam promissores e por vezes únicos em diversas aplicações tecnológicas e industriais. Este trabalho apresenta os resultados de um estudo que objetiva a investigação da evolução temporal do perfil topográfico de superfície de filmes produzidos por processos a plasma a partir do Acetileno. São apresentados resultados sobre a estrutura molecular e propriedades como rugosidade e molhabilidade dos filmes poliméricos. O experimento foi realizado num reator a plasma, cilíndrico de pyrex, excitado indutivamente por rádio-freqüência. O plasma foi gerado a partir do monômero Acetileno numa pressão de 100mTorr, excitado por uma rádio-freqüência (13,56MHz) à 35W de potência. Deposições foram realizadas sobre substratos de InP com dois tipos de perfis de superfície: com padrão bem definido e sem definição. Para caracterização dos filmes foram utilizadas diferentes técnicas de diagnósticos: espectroscopia infravermelha para o estudo da estrutura molecular, medida de ângulo de contato e energia de superfície através de um goniômetro e microscopia de força atômica (AFM) para o estudo de topografia de superfície dos filmes. Os resultados indicaram que a estrutura dos filmes permaneceu constante independente do tempo de deposição. O caráter hidrofílico dos filmes foi mantido ao longo do tempo, com o ângulo de contato medido em torno de 50º. A microscopia 15 (AFM) mostrou as estruturas nanométricas da superfície dos filmes e ainda a rugosidade e a espessura dos mesmos. A constância média no valor do ângulo de contato medido e a constância da estrutura química dos filmes sugerem que a rugosidade da superfície dos mesmos seja também constante. Esta influência é comprovada pelas imagens e... . / Considerable efforts have been made by the internacional community to study plasma polymeric films motivated by interesting features of these films in technological and industrial applications. The present work reports the investigation on the time evolution of topographic profile of the surface of films produced by plasma processing with Acetylene. The results on the study of molecular structure and properties such as roughness and wettability were reported as well. The experiment was performed in a cylindrical Pyrex plasma reactor in inductively coupled configuration. The plasma was generated in Acetylene at 100mTorr with a 35W power supply connected to a circular antenna around discharge tube. Depositions were performed on InP substrate with a well defined and undefined profile patternof the surface. To characterize the films, different techiniques were applied: Fourier Transform Infrared Spectroscopy to study molecular structure, goniometer to measure contact angle and surface energy and Atomic Force Microscopy (AFM) to study the topography of the films. The results indicated that the structure of the films were the same, i.e., independent of the time used to produce the film. High hydrophilic films were obtained with contact angle around 50º. The AFM showed the nanoscale structure of the films surfaces and values of film thickness as well. Approximate same value of contact angle and chemical strcture in the films suggested same roughness on its surface. This was conffirmated by observations with AFM. 17 The images of microscale structure of film surface shows that original topography of the substrate are reproduced on the film. In conclusion, polymeric thin films on the InP substrate produced with Acetylene plasma are hydrophilic for well defined and undefined profile pattern of substrate surface. They have also similar chemical... (Complete abstract, click electronic address below).

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