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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.
301

Unravelling experiences of self: developmental issues in borderline psychopathology

Hoyle, Georgine 26 February 2007 (has links)
Student Number : 8887128 - PhD thesis - School of Psychology - Faculty of Humanities / There is a manifest similarity between the disorders of deficient attention and borderline psychopathology as they are described in the DSM IV. In my experience, those with borderline psychopathology have a history of problems with attention. This study seeks to explore the experiential link between the two disorders and how deficient attention acts as a precipitant factor in the development of borderline psychopathology. Ten interviews were conducted with adults diagnosed as having borderline personality disorder with a history of deficient attention. The interviews were unstructured, audiotaped and transcribed. The transcriptions were analysed according to the method of thematic content analysis. The transcriptions were also rerepresented in the testimonial form of life history. The data produced seven categories of experience, set in an overall context of trauma. Attention formed only one of these categories. The others were incoherence, incompetence, discord, refraction, dispossession and persecution. The categories, together with existing literature, were linked to form a traumatogenic model of the development of borderline psychopathology. This constitutes an extension of existing literature and is intended to contribute to the prevention and treatment of both disorders.
302

The Paternal Dilemma: Fathers, Sons and Inheritance in Shakespearean Drama

Keener, Andrew S. January 2010 (has links)
Thesis advisor: Andrew Sofer / In this thesis, it is my task to explore Shakespeare’s social analysis concerning the patriarchal structure of the family and the economic implications of this system. Four plays in particular, King Lear, Henry IV, As You Like It, and The Tempest resonate with these thematic elements. At the heart of these plays is the issue I call the paternal dilemma; the father or patriarch is a mere human, cannot live forever, and therefore needs to rely on an inheritance scheme to ensure the continuation of his line. This problem sees the institution of inheritance (namely, primogeniture) as a solution or antidote to mortality. In an investigation of these issues, I place myself in an already rich field of secondary criticism, examining how genre and family structure combine in what is ultimately a conservative understanding of the Elizabethan family. / Thesis (BA) — Boston College, 2010. / Submitted to: Boston College. College of Arts and Sciences. / Discipline: English Honors Program. / Discipline: English.
303

Aerosol Optical Properties in the South Atlantic Ocean

Wilson, Dale 17 January 2012 (has links)
MSc., Faculty of Science, University of the Witwatersrand, 2011 / Atmospheric aerosols have direct and indirect impacts on the earth’s radiation budget and the radiative forcing on the climate system. A large uncertainty exists regarding aerosols and the effect they have on the earth’s radiation budget and global change. The distribution, concentration and types of aerosols are therefore of great importance regarding global warming and climate change. The purpose of this study is to present the atmospheric aerosol characteristics found over the South Atlantic, Southern Ocean and Antarctic continent as well as identify their origin. The aerosol optical properties over the South Atlantic and Southern Ocean region is analysed during the South African National Antarctic Expedition 2007/2008 (SANAE 47) take over cruise on board the M/V S.A. Agulhas. Very low aerosol optical thickness (AOT) values were obtained for the Antarctic Coastal region with a mean AOT500nm of 0.03 and a mean Angstrom exponent of 1.78. The South Atlantic region showed a mean AOT500nm of 0.06 and a mean Angstrom exponent of 0.72. AOT values for the South African coastal region had a mean AOT500nm of 0.07 and a mean Angstrom exponent of 0.76. Data comparisons confirm that the data acquired during the study are consistent with previous research from the study region. Comparisons were made between the dataset and the MODIS satellite aerosol product. A discrepancy was shown to exist between the MODIS aerosol product and the acquired dataset using the Microtops II Sunphotometer. Both MODIS TERRA and AQUA overestimate AOT at 550nm.
304

Vägen från platsvarumärke till det fysiska rummet.

Maleus Larsson, Hanna January 2019 (has links)
Sedan en tid tillbaka arbetar flera länder, regioner och större städer med platsvarumärke. Detta används till marknadsföring av sin plats men även för att framhäva det som karaktäriserar eller är unikt för platsen. Idag syns platsvarumärken på kommunen och mindre städer. En snabb sökning av platsvarumärke på internet visar att flera kommuner arbetar aktivt med att utveckla sitt platsvarumärke. Tydligt syns det att platsvarumärke idag är ett aktuellt ämne för kommuner och lokalpolitiker att lyfta fram det som karaktäriserar sin plats och sin framtida utveckling. Kommunen kan med platsvarumärket belysa vad man vill utveckla och vad kommunen anser vara betydande för platsen. Detta kan vara lokaliseringen eller det som anses vara kommunens identitet och det man vill framställa sig som. Syftet med denna uppsats är att få en djupare förståelse för begreppet platsvarumärke för en kommun och hanteras i fallet Lund och Brunnshög. Undersökningen riktar sig till hur platsvarumärket och samhällsplaneringen påverkar varandra i en kommun och om platsvarumärket påverkar utformningen av det fysiska rummet. För att få en förståelse för hur platsvarumärket finns i planeringsdokument har litteraturstudie genomförts med metoden kvalitativ innehållsanalys. I analysen appliceras det teoretiska ramverket och kunskapsöversikten som utgår från platsvarumärke och samhällsplanering. Undersökningsmaterialet har varit Lunds översiktsplan 2010 och fördjupade översiktsplanen för Lund NE/Brunnshög. För att besvara frågeställningen undersöks även två detaljplaner för att finna hur utformningen av det fysiska rummet skett. Slutsatserna som kan dras av undersökningen är att det finns inga tydliga kopplingar mellan detaljplanerna och platsvarumärket. Däremot finns kopplingarna mellan platsvarumärket och översiktsplanen och fördjupade översiktsplanen. Vidare frågeställningar har uppkommit i arbetet med uppsatsen om hur påverkan mellan platsvarumärket och den valda utvecklingen av större bebyggelse sker.
305

Influência do casquete (com ou sem contato cervical com a estrutura moldada) e da moldeira de estoque, para um único elastômero, sobre a precisão dimensional de troquéis de um gesso tipo IV

Gomes de Sá, André Tomazini 26 May 2003 (has links)
O objetivo no presente trabalho foi avaliar a fidelidade dimensional de troqueis de gesso tipo IV (Vel-Mix®), obtidos a partir de moldes de um único elastômero (Impregum® F), utilizando-se duas diferentes técnicas de moldagem (com casquete ou com moldeira de estoque). A fidelidade de cada troquel obtido foi avaliada através de uma coroa-padrão, a qual encaixava-se com alta precisão ao troquelpadrão, o qual era a estrutura original a ser moldada. Assim foram compostos os 4 seguintes grupos, com o aquecimento do molde não tendo sido efetuado apenas no primeiro deles: 1- do casquete de resina, sem contato com a porção cervical do troquel-padrão (Cstsa); 2- do casquete, também sem o referido contato (Cstca) ; 3- novamente do casquete, agora com contato (Cctca) e 4-. da moldeira de estoque perfurada (Mca). Com base nos resultados encontrados nas condições estabelecidas, após o respectivo tratamento estatístico, foi possível concluir que: 1 - o pior desempenho ocorreu com a moldeira perfurada, com um desajuste médio da ordem de 397, 70 micrometros; 2 - o casquete com toque e com aquecimento (desajuste médio de 85,37 micrometros) apresentou desempenho semelhante ao do casquete sem toque e sem aquecimento (desajuste médio de 102,38 micrometros) e 3 - o melhor desempenho ocorreu com o casquete sem toque e com aquecimento, com um desajuste médio de 0, 03 micrometros. / The aim in this study was to evaluate the dimensional accuracy of dies made with a type IV stone (Vel-Mix®) dies, obtained from moulds of a sole elastomer (Impregum® F), by employing 2 different moulding techniques, with a shell or with a perforated stock tray. Stone dies accuracy was measured by means of a standard crown which could be accurately fitted to the standard die, the original structure to be moulded. In this way, the following 4 groups were stablished, with the mould heating not being done only in the first of them: 1- with the acrylic resin shell cervically not contacting the standard die; 2- with the refered shell but without that contact; 3- once more with the shell, again with that contact and 3- with the stock tray. Under the stablished conditions, after statistical treatment of results, the following conclusions could be drawn: 1- worst performance was presented by the stock tray, with a 397,70 µm mean inaccuracy; 2- the shell performance with cervical contact and heated (85,37 µm mean inaccuracy) was similar to that of it without contact and without heating (102,38 µm mean inaccuracy) and 3- better performance was presented by shell without contact and with heating, with a 0,03 µm mean inaccuracy.
306

Mucopolissacaridose IVA : análise molecular e caracterização de haplótipos intragênicos no gene Galns

Bochernitsan, Aline Nemetz January 2015 (has links)
Introdução: Mucopolissacaridose IVA é uma doença lisossômica, autossômica recessiva, causada pela deficiência da enzima N-acetilgalactosamina-6-sulfatase. É uma doença rara e a incidência varia de 1:76.000 a 1:640.000 recém-nascidos vivos. Até o momento 319 diferentes mutações causadoras da doença já foram identificadas, o que demonstra a ampla variabilidade genética. Objetivo: Caracterizar o genótipo de pacientes com MPS IVA, analisar 6 polimorfismos intragênicos e identificar os haplótipos presentes em nossos pacientes, através do estudo molecular do gene GALNS. Métodos: O estudo foi realizado em 45 pacientes provenientes das regiões Nordeste, Sudeste, e Sul do Brasil, com diagnóstico bioquímico confirmado para MPS IVA. A análise molecular foi realizada através de PCR seguida de sequenciamento, pelo método de Sanger, a fim de identificar as mutações causadoras da doença. Para o estudo de haplótipos foram analisados 6 polimorfismos intragênicos através de PCR em Tempo Real, pelo método Taqman, em pacientes e controles. Resultados: A análise do gene GALNS, nos 45 pacientes, permitiu a identificação de 18 diferentes mutações, e a caracterização de 6 haplótipos distintos. Das 18 mutações encontradas, 5 apresentaram uma alta frequência (p.Ser341Arg, p.Arg386Cys, p.Gly301Cys, p.Arg94Leu e p.Gly116Ser), além disso, foram encontradas 4 novas mutações em outros três pacientes (p.Gly115Arg, p.Asn45Gly, p.Thr394Ala e c.759-2A>G). Dentre as mutações encontradas com maior frequência, a mutação p.Ser341Arg foi identificada em um maior número de pacientes, sendo a maioria proveniente da região Nordeste. Além disso, todos os pacientes com esta mutação apresentaram um único haplótipo. Conclusão: Os resultados obtidos permitiram a identificação de 18 mutações dentre elas 4 novas mutações. A alta frequência da mutação p.Ser341Arg no Nordeste do Brasil, principalmente no estado da Paraíba nos leva a inferir um possível efeito fundador da doença. Esta mutação foi observada somente na população brasileira e todos os pacientes com mutação em homozigose apresentaramum único haplótipo. Estas análises são importantes para identificar portadores nas famílias, para diagnóstico pré-natal, e também como forma de identificar uma origem comum em mutações frequentes em determinadas populações. / Background: Mucopolysaccharidosis IVA is an autosomal recessive lysosomal disease, caused by deficiency of N-acetilgalactosamina-6-sulfatase. It is a rare disease and the incidence ranges from 1: 76,000 to 1:640,000 live births. To date 319 mutations have been identified in this gene, demonstrating the wide variability of disease causing mutations. Objective: Analyze and characterize the genotype of patients with MPS IVA, through molecular analysis of GALNS. Methods: Molecular analysis of 45 patients with confirmed biochemical diagnosis for MPS IVA was performed. Mutation analysis was performed by PCR followed by Sanger sequencing. Haplotype analysis was performed using 6 intragenic polymorphisms by Real-Time PCR. Results: In this study we found 18 different mutations among 45 Brazilian patients and identified 5 common mutations (p.Ser341Arg, p.Arg386Cys, p.Gly301Cys, p.Arg94Leu e p.Gly116Ser). Four novel mutations were also identified through molecular analysis, including: p.Gly115Arg, p.Asn45Gly, p.Thr394Ala e c.759-2A>G. Patients are distributed in Northeast, Southeast and South regions of Brazil. Six different haplotypes were identified among patients. The p.Ser341Arg mutation showed the highest frequency, and most patients are located in the Northeast, additionally, all patients with this mutation show the same haplotype.Conclusion: These analyzes are important to identify carriers in families, for prenatal diagnosis, and in order to identify the mutation origin when certain recurrent mutation is associated with the same haplotype. In this study, we observed a high frequency of p.Ser341Arg mutation in Northeast, mainly in the state of Paraíba. This mutation was detected with higher frequency among patients, and showed only a haplotype. This mutation is unique for the Brazilian population and thus, we could suggest that a possible founder effect for this mutation could exist.
307

Taxa de ingestão potencial em pastejo : um estudo contrastando pastos de clima temperado e tropical / Short-term forage intake rate under grazing conditions: a study contrasting temperate and tropical pastures

Mezzalira, Jean Carlos January 2013 (has links)
Nesta tese investigaram-se relações de causa-efeito em curto prazo entre a estrutura do pasto e parâmetros do comportamento ingestivo de bovinos. Criaram-se contrastes de estruturas de pasto com uma espécie temperada e outra tropical e métodos de pastoreio (contínuo e rotativo). Os experimentos com Cynodon sp. cv. Tifton 85 (1 e 2) foram conduzidos entre janeiro e março de 2011. Os com Avena strigosa cv. Iapar 61 (3 e 4), entre julho e setembro de 2011. A altura de pasto que proporcionou a máxima taxa de ingestão (TI) no pastoreio contínuo foi considerada como altura pré-pastejo nos Experimentos 2 e 4, que simulavam o pastoreio rotativo. A esta altura impôs-se níveis de rebaixamento de 20; 40; 60 e 80%. O delineamento utilizado em todos os experimentos foi o de blocos completos casualizados com quatro repetições. O consumo foi estimado pela técnica da dupla pesagem. Os animais foram equipados com aparelhos registradores de movimentos mandibulares. As máximas TI foram observadas em 20 cm em Cynodon sp. e em 30 cm em A. strigosa. Animais não gastaram tempo adicional para tomar um bocado de equivalente massa no pasto alto em relação ao pasto baixo. No pastoreio rotativo a TI, manteve-se constante, até que 31 e 18% da altura inicial fossem removidos da pastagem alta e baixa, respectivamente. A A. strigosa permitiu maior TI potencial. Os animais gastaram mais tempo por bocado para consumir uma equivalente massa de bocado em Cynodon sp. em relação à A. strigosa, em ambos os métodos de pastoreio. / This thesis investigated cause-effect relationships between sward structure and short-term ingestive behavior of cattle. Contrasting sward structures were created with one temperate and one tropical species combined with two grazing methods (continuous and rotational). The experiments with Cynodon sp. cv. Tifton 85 (1 and 2) were carried out between January and March 2011. Those with Avena strigosa cv. Iapar 61 (3 and 4) took place between July and September 2011. The sward height that provided the highest short-term intake rate in continuous grazing, was regarded as pre-grazing in Experiments 2 and 4, which simulated rotational grazing. For this sward height, four intensities of herbage removal by grazing were imposed, namely 20, 40, 60 and 80%. A randomized complete block design was used in all experiments with four replicates. Intake was estimated by the double-sampling technique. Animals were equipped with IGER behavior recorder. The maximum short-term intake rates were observed at 20 cm for Cynodon sp. and 30 cm for A. strigosa. There was no difference in time required for a single bite between short and tall pastures. Under rotational grazing, intake rate was constant until 31 and 18% of the original tall and short sward heights were removed, respectively. A. strigosa was conducive to a higher short-term intake rate. Animals spent longer time per bite to ingest equivalent masses of Cynodon sp. in comparison to A. strigosa in both grazing methods.
308

Anthrax, Matrix Biology, and Angiogenesis: Capillary Morphogenesis Gene 2 Mediates Activity and Uptake of Type IV Collagen-Derived Anti-Angiogenic Peptides

Finnell, Jordan Grant 01 June 2017 (has links)
Capillary Morphogenesis Gene 2 (CMG2) is a type I transmembrane, integrin-like receptor. It was originally identified as one of several genes upregulated during capillary formation. It was subsequently identified as one of two physiological anthrax toxin receptors, where CMG2 serves as a cell-surface receptor for anthrax toxin and mediates entry of the toxin into cells via clathrin-dependent endocytosis. Additionally, loss-of-function mutations in CMG2 cause the genetic disorder hyaline fibromatosis syndrome (HFS), where the core symptom is dysregulation of extracellular matrix homeostasis (ECM), including excessive accumulation of proteinaceous hyaline material; HFS clearly indicates that CMG2 plays an essential function in ECM homeostasis and repair. Most often, these situational roles have been evaluated as separate intellectual and experimental entities; consequently, whereas details have emerged for each respective situational role, there has been little attempt to synthesize knowledge from each situational role in order to model a holistic map of CMG2 function and mechanism of action in normal physiology.The work presented in this thesis is an example of such a synthesis. Interactions between CMG2 and type IV collagen (Col IV) were evaluated, to better understand this putative interaction and its effect on CMG2 function in angiogenesis. Using an overlapping library peptide array of the Col IV α1 and α2 chains, it was found that CMG2-binding peptides were enriched within the NC1 domains. This finding was corroborated via another epitope mapping peptide array, where we found a major epitope for CMG2-binding within the α2 NC1 domain (canstatin). Identification of CMG2 interactions with Col IV NC1 domains (including canstatin) was both surprising and intriguing, as these domains are potent endogenous inhibitors of angiogenesis. To further evaluate the physiological relevance of interactions with Col IV NC1 domains, a canstatin-derived peptide from the original array was synthesized and used for further studies. This peptide (here known as S16) binds with high affinity (KD = 440 ± 160 nM) to the extracellular, ligand-binding CMG2 vWA domain; specificity was confirmed through competition studies with anthrax toxin PA, and through demonstration of divalent cation-dependent binding. CMG2 was found to be the relevant endothelial receptor for S16. CMG2 in fact mediates endocytic uptake of peptide S16, as demonstrated by flow cytometry, and colocalization studies. S16 further inhibits migration of endothelial cells. These findings demonstrate that CMG2 is a functional receptor for Col IV NC1 domain fragments. CMG2 may exert a pro-angiogenic effect through endocytosis and clearance of anti-angiogenic NC1 domain fragments. Additionally, this is the first demonstration of CMG2-mediated uptake of an endogenous matrix fragment, and suggests a mechanism by which CMG2 regulates ECM and basement membrane homeostasis, thereby establishing a functional connection between the receptor's role in matrix biology and angiogenesis.
309

Monolithic Heterovalent Integration of Compound Semiconductors and Their Applications

January 2019 (has links)
abstract: Compound semiconductors tend to be more ionic if the cations and anions are further apart in atomic columns, such as II-VI compared to III-V compounds, due in part to the greater electronegativity difference between group-II and group-VI atoms. As the electronegativity between the atoms increases, the materials tend to have more insulator-like properties, including higher energy band gaps and lower indices of refraction. This enables significant differences in the optical and electronic properties between III-V, II-VI, and IV-VI semiconductors. Many of these binary compounds have similar lattice constants and therefore can be grown epitaxially on top of each other to create monolithic heterovalent and heterocrystalline heterostructures with optical and electronic properties unachievable in conventional isovalent heterostructures. Due to the difference in vapor pressures and ideal growth temperatures between the different materials, precise growth methods are required to optimize the structural and optical properties of the heterovalent heterostructures. The high growth temperatures of the III-V materials can damage the II-VI barrier layers, and therefore a compromise must be found for the growth of high-quality III-V and II-VI layers in the same heterostructure. In addition, precise control of the interface termination has been shown to play a significant role in the crystal quality of the different layers in the structure. For non-polar orientations, elemental fluxes of group-II and group-V atoms consistently help to lower the stacking fault and dislocation density in the II-VI/III-V heterovalent heterostructures. This dissertation examines the epitaxial growth of heterovalent and heterocrystalline heterostructures lattice-matched to GaAs, GaSb, and InSb substrates in a single-chamber growth system. The optimal growth conditions to achieve alternating layers of III-V, II-VI, and IV-VI semiconductors have been investigated using temperature ramps, migration-enhanced epitaxy, and elemental fluxes at the interface. GaSb/ZnTe distributed Bragg reflectors grown in this study significantly outperform similar isovalent GaSb-based reflectors and show great promise for mid-infrared applications. Also, carrier confinement in GaAs/ZnSe quantum wells was achieved with a low-temperature growth technique for GaAs on ZnSe. Additionally, nearly lattice-matched heterocrystalline PbTe/CdTe/InSb heterostructures with strong infrared photoluminescence were demonstrated, along with virtual (211) CdZnTe/InSb substrates with extremely low defect densities for long-wavelength optoelectronic applications. / Dissertation/Thesis / Doctoral Dissertation Electrical Engineering 2019
310

Effect of the lingual margin configuration on the fracture strength of class IV resin based composite restorations under static loading

Garcia Martinez, Nubia Carolina 01 July 2015 (has links)
Resin-based composite for Class IV restoration is a conservative alternative for maxillary incisor fracture. Little is known about the effect of lingual margin configurations on the longevity of these restorations. This in vitro experiment compared the mean fracture strength among four lingual margin configurations (butt joint, 45° bevel, 60° bevel and chamfer) for Class IV resin-based composite restorations. A total sample size of n=100 human extracted lower incisors were selected, then the teeth were randomly assigned to one of the four lingual margin configuration groups (n=25) and restored with resin-based composite. After thermocycling (5000 cycles, 5°C-55°C with 30 seconds dwell time), they were subjected to inter-incisal static load (135° angulation) until failure (N). Failure mode was determined. In vitro fracture strength was compared among the four groups using one-way ANOVA at alpha=0.05. Mean standard deviation of fracture strength and frequency distribution of failure modes were reported. Results revealed no significant effect on the fracture strength for the type of lingual margin configurations (F(3,96)=0.13; p=0.9435). The data showed that 71% of failure modes resulted in complete tooth fracture (intact restoration), 11% in total adhesive failure, 7% in adhesive only facial, 6% in total cohesive, 4% in cohesive only facial, 1% in avulsion. Fischer’s exact test revealed no statistically significant association (p>0.05) between the margin configurations and failure modes. Within the limitations of this study, it can be concluded that any of the four lingual margin configurations are acceptable in Class IV preparation in terms of fracture strength under static load.

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