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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

Blisters

Walton, Kristina A 17 May 2013 (has links)
n/a
32

Assessing fragile sites in carcinogenic environments: Is this an alert signal?

Stafne, Annwyn Pamela 16 November 2006 (has links)
Student Number : 9901196J - MSc dissertation - School of Pathology - Faculty of Science / Fragile sites are highly unstable regions of the genome, which have a tendency to form gaps and breaks in metaphase chromosomes under replication stress conditions. There are many common fragile sites in the human genome and exposure to carcinogens may affect several genes localised in fragile sites within a single cell, which could lead to activation of oncogenes and inactivation of tumour-suppressor genes simultaneously. FRA3B on chromosome 3 and FRA16D on chromosome 16 are the two most commonly expressed fragile sites and contain the FHIT and WWOX genes respectively. These genes are tumour suppressor genes and are inactivated in a number of different ways. Carcinogens found in cigarette smoke have been found to increase fragile site expression and could alter the integrity of theses genes in active smokers. Ten healthy non-smoking (control) individuals and twenty active smokers were recruited for the purpose of this study. Fluorescence in situ hybridisation was performed with probes spanning spanning the FHIT gene and RT-PCR was performed to assess both FHIT and WWOX expression. No significant difference in breaks at fragile sites was observed between controls and active smokers in the FISH experiments. In addition, no aberrant transcripts were detected for either FHIT or WWOX with RT-PCR. Although the sampling group was limited and heterogenous, no increase in the expression of breaks at fragile sites was seen in active smokers in the present study.
33

Transição de fase no efeito Hall, em camadas de inversão de materiais com gaps estreitos. / Phase transition in the Hall Effect in inversion layers, of materials with narrow gaps.

Santos, Marta Silva dos 18 July 1989 (has links)
A Aproximação de Massa Efetiva para a função evnvelope multi-componente, na presença de uma interface, desenvolvida por Marques e Sham, será utilizada aqui, para materiais de gap estreito do grupo II-VI, da seguinte maneira: A) A forte interação entre bandas de condução e valência, nestes materiais, é justificada em um Hamiltoniano de Kane (6x6) modificado, contendo todas as ondas de Bloch propagantes e evanescentes. Na presença de uma interface, a função de onda eletrônica, &#936, é composta de uma onda de Bloch incidente, uma refletida e duas evanescentes, com a mesma energia E e momento paralelo k. Já que a estrutura da maioria dos isolantes utilizados são desconhecidos, a interface semicondutor-isolante por ser considerada como uma barreira infinita, de modo que, &#936, se anule na interface. Existe uma fina região de espessura &#945 na interface, onde o decaimento das ondas evanescentes é indispensável. Distante desta região, as ondas evanescentes possuem um papel insignificante e eventualmente anulam-se. O limite de &#945 &#8594 0 determina as condições de contorno para cada componente da função de onda envelope na interface. B) As condições de contorno são usadas para computar a estrutura de subbandas e o potencial auto-consistente para o Hg1-xCdxTe. A mais interessante característica é o afastamento dos estados de spin duplamente degenerados. Estes resultados serão utilizados para encontrarmos a dependência da energia das subbandas com um campo magnético perpendicular à interface. C) A magneto-condutividade longitudinal é calculada como função do campo magnético B &#8869. Efeitos das interações elétron-elétron e elétrons-impureza são levadas em conta nas aproximações de Hartee-Foch e auto-consistente de Born, respectivamente. Para uma interação elétron-impureza finita, encontram-se fatores de preenchimentos críticos dos níveis de Landau, onde transições de fase são observadas. Estes resultados explicam as descontinuidades presentes, em medidas experimentais, na magneto-resistividade longitudinal e transversal (Hall), em MISFET de Hg (Cd)Te. / The Effective Mass Approximation for multi-component envelope wave function in the presence of an interface in the MOSFET system, developed by Marques and Sham, will be used here, for II-VI narrow-gap semiconductors, in the following way: A) The strong interaction between conduction and valence bands, in these materials, is justified. The (6x6) Kane type modified Hamiltonian is used and the total wave function contains every propagating and evanescent waves. For an interface, the total function, &#936, is composed of one incident and one reflected and two evanescent Bloch waves, with energy E and parallel wave-vector k. Since the band structure of the most used insulators is usually not well known, the insulator-semiconductor interface can be assumed as an infinite barrier; therefore, the total wave-function there can set to zero. The semiconductor evanescent Bloch waves are indispensable in a thin layer, of thickness &#945, close to this region. Far away from the interface their role are insignificant and can be neglected. In the limit &#945 &#8594 0, the boundary condition for each the limit the total Bloch wave function, are derived. B) These boundary conditions are used to calculate the self-consistent electric subband and potential for MISFET of Hg1-xCdxTe. The subbands present a very important spin splitting, due to the internal electric field. C) The effect of a perpendicular magnetic field is also studied and the longitudinal magneto-conductivity are calculated. The effect of electron-electron and electron-impurity interactions are respectively accounted for in the Hartee-Fock and self-consistent Born approximations. For critical electron-impurity interaction, the Landau level filling shows a phase transition at a given fractional occupation (or magnetic field). These results are experimentally observed in both longitudinal and transverse (Hall) magneto-resistance for Hg(Cd)Te.
34

Metodologia alternativa ao preenchimento de falhas para a geração de séries de precipitação mensal média de forma automatizada em ambiente SIG / Alternative methodology to gap filling for generation of monthly rainfall series with GIS approach

Bielenki Júnior, Cláudio 23 February 2018 (has links)
Alternativamente ao preenchimento de falhas, buscou-se neste estudo apresentar uma metodologia para a geração de séries de precipitações mensais médias apenas com os dados observados disponíveis nas estações pluviométricas presentes na área de estudo e seu entorno. Neste caso, para cada época da série, somente os dados disponíveis foram utilizados para o cálculo da precipitação média, assim em cada época admitiu-se que uma combinação diferente de postos pluviométricos fosse utilizada para o seu cálculo. Para isso foi desenvolvida uma ferramenta computacional em ambiente SIG para automatizar todas as etapas do estudo. Os resultados das séries de precipitação mensal média para uma bacia hidrográfica calculados segundo a metodologia alternativa apresentada foram comparados a dois métodos de preenchimento de falhas comumente utilizados nos estudos hidrológicos. Posteriormente foram avaliados os impactos do quantitativo de falhas nas séries. Também foram avaliados os reflexos na aplicação das séries na modelagem chuva-vazão e por fim a metodologia foi aplicada a um caso concreto. Os resultados encontrados e os testes estatísticos apontam resultados satisfatórios e equivalentes nas condições testadas. Verificou-se uma degradação na correlação entre a série gerada a partir dos dados sem falhas e as séries geradas com os dados com as imposições das falhas com o aumento do número de falhas impostas. As séries de vazões médias mensais geradas utilizando-se o modelo mensal SMAP quando da aplicação das séries de precipitação calculadas pela metodologia alternativa também se mostraram equivalentes, segundo os testes estatísticos realizados, às séries geradas de dados de precipitação sem falhas ou com as falhas preenchidas. As diferenças encontradas entre as séries foram pequenas o que se refletiu nos Índices de Nash-Sutcliffe que foram próximos. / In this study, we proposed a methodology for the generation of average monthly rainfall series only with the observed data available in the rainfall stations present in the study area and its surroundings. In this case, for each season of the series only the available data were used for the calculation of the average precipitation, so in each season it was admitted that a different combination of pluviometric stations was used for its calculation. For this, a computational tool was developed with a GIS approach to automate all stages of the study. The results of the average monthly rainfall series for a river basin calculated according to the alternative methodology presented were compared to two methods of filling gaps commonly used in hydrological studies. Subsequently, the impacts of the number of failures in the series were evaluated. We also evaluated the reflexes in the application of the series in the rainfall-flow modeling and finally the methodology was applied to a case study. The results found and the statistical tests show satisfactory and equivalent results under the conditions tested. There was a degradation in the correlation between the series generated from the data without fail and the series generated with the data with the impositions of the failures with the increase of the gaps imposed. The series of monthly average flows generated using the SMAP monthly model when applying the rainfall series calculated by the alternative methodology were also shown to be equivalent, according to the statistical tests carried out, to the series generated of data of precipitation without gaps or with the gaps fulfilled. The differences found between the series were small, which was reflected in the Nash-Sutcliffe Indices that were close.
35

Air Gap Method : Air-Gaps in Building Construction to avoid Dampness & Mould

af Klintberg, Tord January 2012 (has links)
<p>QC 20120928</p>
36

Roles of Foreign Aid in Narrowing Development Gaps: A Cross-Country Analysis on Aid, Institutions, and Growth

HIRANO, Yumeka 18 March 2013 (has links)
No description available.
37

Essays on Labor Economics and Fiscal Decentralization

Canavire-Bacarreza, Gustavo J 14 December 2011 (has links)
This dissertation comprises two essays. While the topics of both essays are different both are interrelated on the base of economic development. The first essay examines ethnic wage gaps on segmented labor markets with evidence from Latin American countries. The second essay revisits the determinants of fiscal decentralization with an emphasis on the role that geography plays in determining fiscal decentralization. The first essay contributes to limited literature on ethnic wage gaps in Latin America. It examines ethnic wage gaps for workers in formal and informal labor markets. Using data from Latin American countries we estimate and examine across-ethnic wage gaps for informal and formal markets, their changes over time, factors that explain their differences, and the wage gap distribution. More specifically, we verify that different ethnic wage gaps do exist across formal and informal markets; they behave differently not only at their means but also along the wage distribution. The results indicate that higher ethnic wage gaps in informal sectors exist not only on average but also throughout the distribution. In addition, we find that wage gaps have declined significantly over the last 10 years. we explain this by examining changes in the prices of institutional factors and changes in human capital endowments. The distributional analysis shows a decrease in the unexplained component, especially in the top part of the distribution. The second essay contributes to the existing literature on the determinants of fiscal decentralization by motivating theoretically and exploiting in depth the empirical relevance that geography has as a determinant of fiscal decentralization. The relationship between decentralization and geography is based on the logic that more geographically diverse countries show greater heterogeneity among their citizens, including their preferences and needs for public goods and services provisions. Communications and physical distance are also a very important issue and play a key role on the effect of geography over time. (Lora et. al., 2003) argue geography plays a key role in economic and social development, as well as in the institutional design of the countries; yet, this effect could be enhanced (or diminished) in the presence of better physical infrastructure or communications. The theoretical model in this paper builds on the work by Arzaghi and Henderson (2002) and Panizza (1999). For the empirical estimation, we use a panel data set for approximately 91 countries for the period 1960-2005. Physical geography is measured along several dimensions, including elevation, land area and climate. We construct a geographical fragmentation index and test its effect on fiscal decentralization. In addition, we interact the geographical fragmentation index with time-variant infrastructure variables in order to test the effect that infrastructure and communications have on the relationship between geography and fiscal decentralization. For robustness, we construct Gini coefficients for in-country elevation and climate. We find a positive and strong correlation between geographical factors and fiscal decentralization. We also find that while the development of infrastructure (in transportation, communications, etc.) tends to reduce the effect of geography on decentralization, this effect is rather small and mostly statistically insignificant, meaning that the impact of geography survives over time. The strategy has additional value because geography may be used as an instrument for decentralization in future econometric estimations where decentralization is used as an explanatory variable, but may be suspected to be endogenous to the economic process being studied (economic growth, political instability, macroeconomic stability, income distribution, etc.).
38

Continued Radicals and Cantor Sets

Clark, Thomas Tyler 01 May 2012 (has links)
We examine the formation of sets homeomorphic to the ternary Cantor set by continued radicals. We determine properties of bridges and gaps and calculate the thickness of the Cantor set. From this we apply information from continued fractions to continued radicals to obtain new results. We also consider the measure of several Cantor sets.
39

Schymans ben i Let’s Dance som kommunikationsstrategi : En fallstudie av Feministiskt initiativs kommunikation i valkampanjen 2010

Morell, Joanna January 2010 (has links)
Schyman’s legs in Let’s Dance as a communication strategy - a case study of “Feministiskt initiativ” in the election campaign 2010. (Schymans ben i Let’s Dance som kommunikationsstrategi, en fallstudie om Feministiskt initiativ i valkampanjen 2010). Author: Joanna Morell, Tutor: Ann-Marie Morhed 2009 was the first time where Swedish political parties were entitled to have TV- commercials, another sign of political communication taking one step closer to the strategic marketing communication. A type of communication that also is expensive. The Swedish political party Feministiskt initiativ (Fi) have existed since 2005 and is not yet a part of the Swedish parliament. They have not been entitled to the economic support that is given to Swedish parties with more than 2,5 percent of the votes in the last two elections. As a result Fi is completely dependent on economic contributions. Because of this it is crucial for them to get good value for the money they spend on communicating their brand. But how can then Fi, who have limited resources, make themselves heard? This question is what makes this study important. The purpose of this study was to investigate Fi and in which degree they made their brand visible to the public in the election campaign of 2010. I wanted to examine how efficiently they ran their election campaign, and by efficiently I mean to what degree the sender and receiver perception matched each other regarding the subjects: profile, communication and communication means. To examine if the sender and receivers perception matches each other; I’ve done a qualitative study, which includes a personal interview with the head of communication for Fi and four group interviews with people who voted for Fi, and people who didn’t. The result of these two will be reflected to theories that involve organizational identity and image, communication gaps and communication planning. The result of my study shows that Fi had small resources to communicate their profile through media. As a result Fi had limited access in media during the election campaign. The party used price efficiently strategies such as social media, network projects and the “brand Schyman” (living the brand). Because of the small resources communication gaps have evolved. Since Fi mainly use the strategy with the party as a network project there is a possibility that the wrong perception of their identity spread, which risks making existing communication gaps even bigger. This essay is 50 pages and is written in the autumn semester of 2010, for the course of Media and Communication Studies C. For the Division of Media and Communication, Department of Information Science, Uppsala University.
40

Analysis of the Wave Propagation in Two-Dimensional Phononic Crystal Using the Finite Element Method

Song, Pei-Jing 28 August 2006 (has links)
In this work we apply the finite element method to analyze the wave transmission property of solid/fluid composite medium, phononic crystal. The sound attenuation spectrum is obtained to show the forbidden bands of the band gap. First, we construct the finite element model for a two-dimensional phononic crystal, studied by S&#x00E1;nchez-P&#x00E9;rez etc. with PWE and experimentally, constituted of a rectangular array of parallel circular stainless steel cylinders in air. It has demonstrated that our simulation work was feasible; then, we performed the experimental measurements and simulations by using the narrow and wide frequencies. The results show agreement between the experiments and the simulations. We also simulated the crystal samples of filling fraction 5 % and 10 % for square and hexagon lattice, respectively, in both the [100] and [110] direction. The full band gaps are determined from the combination of the results. We have investigated the finite element simulation for the solid/fluid phononic crystal successfully. Both work the results of experiment in the reference and in this work are compared with the FEM simulation. It demonstrates that the finite element method is a good tool for the design of phononic crystal in application to new type sound absorption (isolation) material.

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