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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.
271

Cataract from ultraviolet radiation in the mouse /

Meyer, Linda Maren. January 2005 (has links)
Licentiatavhandling (sammanfattning) Stockholm : Karol. inst., 2005. / Härtill 3 uppsatser.
272

Regulation of the redox-mediated platelet-derived growth factor (PDGF) mitogenic function in human lens epithelial cells

Wang, Yin. January 2008 (has links)
Thesis (Ph.D.)--University of Nebraska-Lincoln, 2008. / Title from title screen (site viewed Mar. 31, 2009). PDF text: x, 186 p. : ill. ; 8 Mb. UMI publication number: AAT 3331460. Includes bibliographical references. Also available in microfilm and microfiche formats.
273

Coupled self-assembly and flow alignment of silver nanorods

Murali, Shanthi, Davis, Virginia A., January 2008 (has links) (PDF)
Thesis (M.S.)--Auburn University, 2008. / Abstract. Vita. Includes bibliographical references (p. 86-99).
274

Superoxide dismutase 1 and cataract

Olofsson, Eva, January 2009 (has links)
Diss. (sammanfattning) Umeå : Umeå universitet, 2009. / Härtill 4 uppsatser.
275

Desenvolvimento e caracterização físico-química de sistemas líquido cristalinos contendo palmitato de retinol: quantificação química, avaliação da atividade antioxidante, estudos de liberação e bioadesão in vitro

Oliveira, Paula Lacerda [UNESP] 22 March 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:23:33Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-03-22Bitstream added on 2014-06-13T18:50:46Z : No. of bitstreams: 1 oliveira_pl_me_arafcf.pdf: 2094182 bytes, checksum: 926895d5e73c0de69bc13d5a0444ffcd (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / As hipóteses mais modernas baseiam o processo de envelhecimento cutâneo em duas teorias: o intrínseco (ou cronológico) e o extrínseco (ou fotoenvelhecimento). Tanto no envelhecimento intrínseco como no extrínseco, as principais alterações da pele são caracterizadas por formação de rugas, flacidez e perda da elasticidade. O palmitato de retinol (PR) é um análogo sintético da vitamina A indicado topicamente para prevenir ou retardar algumas mudanças estruturais e funcionais da pele associadas ao processo de envelhecimento cutâneo, porém é um princípio ativo que apresenta estabilidade química limitada frente à umidade, oxigênio, ácidos, metais e exposição à luz. Assim, o objetivo deste trabalho foi desenvolver um sistema líquido-cristalino à base de silicone para a liberação prolongada e maximização da estabilidade do palmitato de retinol. Utilizando-se o método de titulação da fase aquosa, foram construídos dois diagramas ternários de fases, ambos constituídos por Procetyl AWS® (tensoativo) e água e por silicone DC 5330® (fase oleosa no diagrama 1) ou silicone DC 5329® (fase oleosa no diagrama 2). Nos estudos de estabilidade preliminar, as formulações do diagrama 1 (A, B, C e D) e do diagrama 2 (E, F, G e H) foram avaliadas nos seguintes estudos: microscopia de luz polarizada, centrifugação, pH, condutividade eletrolítica, índice de refração e reologia. Dentre estas formulações estudas preliminarmente, a formulação GPR foi selecionada para ser conduzida aos estudos posteriores após a incorporação de 1% do princípio ativo, pois demonstrou a formação de fases líquido-cristalinas evidenciadas sob luz polarizada no microscópio óptico, apresentou-se compatível com o pH fisiológico da pele, apresentou pequeno coeficiente de variação das medidas realizadas referentes aos parâmetros físico- químicos e menor capacidade de desestruturar... / Current hypotheses based on the process of skin aging in two theories: the intrinsic (or chronological) and extrinsic (or photoaging). Both in the extrinsic as intrinsic aging, the main skin disorders are characterized by wrinkles, flaccidity and loss of elasticity. Retinyl palmitate (RP) is a synthetic analogue of vitamin A given topically to prevent or delay some structural and functional changes of the skin associated with aging, but is an active principle that has limited chemical stability against moisture, oxygen, acids , metals and exposure to light. Thus, the aim of this study was to develop liquid crystalline system silicon-based for extended release and maximizing the stability of retinyl palmitate in order to optimize the use of topically active principle in the prevention and / or mitigation of aging skin. Using the method of titration of the aqueous phase, was built two ternary phase diagrams, both consist of Procetyl AWS ® (surfactant) and water and silicone DC 5330 ® (oil phase diagram 1) or silicone DC 5329 ® (phase oil in diagram 2). In preliminary studies of stability, the formulations of the diagram 1 (A, B, C and D) and the formulations of the diagram 2 (E, F, G and H) were evaluated in the following studies: polarized light microscopy, centrifugation, pH, electrolitic conductivity, refraction index and rheology. Among these formulations studied preliminarily, the formulation G RP-loaded was selected to be conducted to further studies, since it showed the formation of liquid crystalline phases evidenced by polarized light in an optical microscope, presented consistent with the physiological pH of skin, had a small coefficient of variation of measurements related to the physicochemical and less ability to disrupt the lipid bilayer of the skin due to have a lower concentration of surfactant. The validated analytical methodology for chemical quantification of retinyl... (Complete abstract click electronic access below)
276

Avaliação do potencial de nanodispersões de cristal líquido funcionalizadas com cetuximabe na veiculação de docetaxel para o tratamento do câncer de próstata /

Trevizan, Lucas Noboru Fatori January 2018 (has links)
Orientador: Marlus Chorilli / Resumo: O câncer de próstata (CP) é a segunda neoplasia mais frequente entre homens no Brasil e é caracterizado por não apresentar sintomas em seus estágios iniciais, sendo diagnosticado em seu estágio avançado, o que muitas vezes dificulta o tratamento. Alguns fatores relacionados podem intensificar sua agressividade como, por exemplo, a superexpressão do receptor do fator de crescimento epidérmico (EGFR) em alguns subtipos de tumores de próstata. Neste contexto, a inibição do EGFR auxilia no combate da neoplasia, função essa que pode ser atribuída ao anticorpo monoclonal quimérico IgG1 (cetuximabe-CTX) que se liga à porção externa do EGFR, inibindo a proliferação celular, angiogênese e metástase, além de promover a apoptose. Dentre as formas de tratamento destacam-se a braquiterapia, a radioterapia e a quimioterapia utilizando o docetaxel (DTX), o qual apresenta vantagem de prolongar a sobrevivência em pacientes com CP metastático resistentes à terapia antiandrogênica. No entanto, a formulação comercial (Taxotere®) causa efeitos colaterais, como febre, anemia, retenção de líquidos, hipersensibilidades, mialgias, mucosite, neuropatias periféricas e toxidade a pele e unhas, tornando necessário o estudo de novas formas de veiculação para este fármaco Deste modo, o objetivo deste trabalho foi desenvolver uma nanodispersão de cristal líquido (NCL) de fase cúbica baseada em álcool cetílico etoxilado 20 e propoxilado 5 como tensoativo (T), ácido oleico, DSPE-PEG-MAL e fosfatidilcolina de ... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre
277

Processos hidrogeoquímicos em águas subterrâneas no cristalino em Caucaia/CE. Contribuição da modelagem inversa através do PHREEQC / Hydrogeochemical processes in groundwater in the crystalline Caucaia / CE. Contribution from inverse modeling by PHREEQC

Santiago, Roberto Namor Silva January 2010 (has links)
SANTIAGO, Roberto Namor Silva. Processos hidrogeoquímicos em águas subterrâneas no cristalino em Caucaia/CE. Contribuição da modelagem inversa através do PHREEQC. 2010. 77 f. Dissertação (Mestrado em Física) - Programa de Pós-Graduação em Física, Departamento de Física, Centro de Ciências, Universidade Federal do Ceará, Fortaleza, 2010. / Submitted by Edvander Pires (edvanderpires@gmail.com) on 2015-10-15T18:01:19Z No. of bitstreams: 1 2010_dis_rnssantiago.pdf: 1685141 bytes, checksum: b666d487f1ddbb3e61b487b7b797e6ee (MD5) / Approved for entry into archive by Edvander Pires(edvanderpires@gmail.com) on 2015-10-21T20:36:04Z (GMT) No. of bitstreams: 1 2010_dis_rnssantiago.pdf: 1685141 bytes, checksum: b666d487f1ddbb3e61b487b7b797e6ee (MD5) / Made available in DSpace on 2015-10-21T20:36:04Z (GMT). No. of bitstreams: 1 2010_dis_rnssantiago.pdf: 1685141 bytes, checksum: b666d487f1ddbb3e61b487b7b797e6ee (MD5) Previous issue date: 2010 / The interaction between groundwater and rocks, occurs through processes of dissolution and precipitation that attest to the hydrochemical evolution within the aquifer system with direct influence on water quality. In this study, we used the application PHREEQC to simulate these processes in water from seven wells in crystalline collected during dry and wet, with the aim of identifying the origin of the salinity of these waters. The results show that (i) the salinity varies in space and time, (ii) are mainly chlorinated water from the mixed type, (iii) the type of water remains in each well (iv) the salinity decreases during the rainy season and increases in dry period, reaching values characteristic of each well, (v) water-saturated goethite, hematite and iron hydroxide III occurred in two wells, calcite, dolomite and aragonite in three wells and two wells in hematite. In the dry and rainy season, there were dissolution of anorthite and K-feldspar, precipitation of K-mica and albite and cationic exchange types CaX2, MgX2, NaX and KX. The waters are more saline in wells that received minor differences in recharges and refills is characteristic of areas in the lens. / A interação entre a água subterrânea e as rochas, ocorre através de processos de dissolução e precipitação que atestam a evolução hidroquímicas dentro do sistema aqüífero com a influência direta na qualidade da água. Nesse trabalho, foi utilizado o aplicativo PHREEQC para simular esses processos em águas de 7 poços no cristalino coletadas nos períodos seco e chuvoso, com o objetivo de identificar a origem da salinidade dessas águas. Os resultados mostram que (i) a salinidade varia no espaço e no tempo; (ii) predomina água do tipo cloretada mista; (iii) o tipo de água se mantém em cada poço (iv) a salinidade diminui no período chuvoso e aumenta no período seco, atingindo valores característicos de cada poço, (v) águas saturadas de goetita, hematita e hidróxido de ferro III ocorreram em dois poços; calcita, dolomita e aragonita em 3 poços e hematita em 2 poços. No período seco e chuvoso, ocorreram dissoluções de anortita e K-feldspato, precipitação de K-mica e albita e trocas catiônicas dos tipos CaX2, MgX2, NaX e KX. As águas mais salinas estão nos poços que receberam menores recargas e as diferenças nas recargas é característica de áreas no cristalino.
278

Análise integrada aplicada à exploração de água subterrânea na Bacia do Rio Jundiaí (SP)

Neves, Mirna Aparecida [UNESP] 16 March 2005 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:21Z (GMT). No. of bitstreams: 0 Previous issue date: 2005-03-16Bitstream added on 2014-06-13T20:03:44Z : No. of bitstreams: 1 neves_ma_dr_rcla.pdf: 12430426 bytes, checksum: 2ab3404f8510043b13aa942ec5d477a4 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Ministério da Ciência, Tecnologia e Inovação (Mcti) / O uso intenso e a poluição dos recursos hídricos superficiais na bacia do rio Jundiaí têm levado à busca acelerada por recursos hídricos subterrâneos. A maior parte da bacia se situa sobre o Embasamento Cristalino, onde o fluxo subterrâneo é condicionado pela presença de descontinuidades. Para investigar o comportamento da água subterrânea neste contexto é necessária, além da caracterização hidrogeológica, a definição das características geológico-estruturais e tectônicas da área. Além do Sistema Aqüífero Cristalino, a bacia envolve também o Sistema Aqüífero Tubarão, situado no lado oeste da área, e o Sistema Aqüífero Cenozóico, distribuído ao longo das drenagens principais. Identifica-se um importante controle estrutural sobre a produtividade dos poços, não só daqueles que explotam as rochas cristalinas, mas também dos que captam água das rochas sedimentares. A integração de dados geológico-estruturais e hidrogeológicos indica que o controle estrutural ocorre principalmente em zonas de abertura, onde esforços transtrativos induzem a formação e/ou reativação de estruturas rúpteis de direção NW-SE e E-W, comumente associadas à presença de depósitos aluviais. Outros fatores de interferência também foram identificados, como a localização dos poços em relação à compartimentação morfoestrutural da área e a superexplotação dos aqüíferos, que, ao contrário daquelas estruturas, tende a diminuir a produtividade dos poços. / The intensive use and pollution of superficial water resources in the Jundiaí River Catchment lead to an increasing groundwater exploitation. The major part of Jundiaí Catchment is located on the Crystalline Basement, where water flow is dependent on discontinuities. In order to investigate the behavior of groundwater in such a context, it is necessary, besides the hydrogeologic characterization, the definition of geologic, structural and tectonic characteristics. The Tubarão Aquifer System occurs on the west side of the area and the Cenozoic Aquifer System is distributed along the main channels. It is possible to identify an important structural control over well productivity, not only on those located in crystalline rocks, but also on those located in sedimentary rocks. The integration of geologic, structural and hydrogeologic data shows that structural control happens mainly in distensive areas, where transtractive tension leads to formation and/or reactivation of brittle NW-SE and E-W structures, commonly associated with the occurrences of alluvial deposits. Other factors that affect well productivity were identified, for example, the location of wells with respect to some morphostructural compartments and the overexploitation of groundwater, which, despite favorable geologic structures, tend to decrease well productivity.
279

Topological properties of SnTe and Fe3Sn2

O'Neill, Christopher David January 2016 (has links)
The aim of this thesis was to identify topologically protected states in the materials SnTe and Fe3Sn2. Such states are currently receiving a large amount of interest due to their applications for spintronic devices. Recently SnTe was discovered to be a crystalline topological insulator, a state of matter where its surface is highly conducting while the bulk remains insulating. However detection of these surface states is difficult using transport measurements, since the bulk is not totally insulating but still contains a large number of free carriers. SnTe undergoes a rhombohedral structural distortion on cooling caused by a soft transverse optic phonon, with the exact Tc strongly dependent on the carrier concentration. The distortion acts to lower crystal symmetry removing some of the symmetries that protect the surface state. Single crystal samples displaying the structural transition were grown and investigated using inelastic X-ray scattering to measure the phonon softening previously reported by other authors. The soft phonon was seen to recover again after distortion indicative of a 2nd order ferroelectric transition. This is the first reported discovery of the recovery showing the distortion is ferroelectric in nature. Shubnikov de Haas quantum oscillations were measured to study the Fermi surface under ambient and high hydrostatic pressure conditions. A distortion of the Fermi surface caused by the structural transition was evident, resulting in 4 distinct oscillation frequencies. However at applied pressures above 6 kbar, the transition was suppressed and only 1 oscillation measured. A two component Hall response also becomes apparent under high pressure. The possible origin of this and its relation to possible surface states is discussed. The anomalous Hall effect was also measured in the ferromagnet Fe3Sn2 which has a bilayer Kagome structure. Previous measurements on polycrystalline Fe3Sn2 suggested a non-collinear spin rotation from the spins pointing along the c-axis at high temperature to lying in the a-b plane below 80 K. A spin glass phase is then expected below 80 K. Single crystal magnetisation measurements carried out in this thesis show the spins are in the a-b plane at high temperatures and begin to display a ferromagnetic component along the c-axis approaching 80 K. The difference is accounted for by considering the demagnetising factor in the plate shaped single crystals. For this temperature range an applied field along the c-direction however rotates the moments towards c. At intermediate fields there are strong features evident in both the anomalous Hall effect and magnetoresistance. These features may be due to a topological Hall effect caused by a non-collinear spin structure. The possible existence of Skyrmion excitations was also recently discussed theoretically in Fe3Sn2. Our data is more suggestive of static Skyrmions known to cause topological Hall effects in MnSi.
280

Simulation de cristaux de cellulose par dynamique moléculaire / Molecular dynamics simulation of crystalline cellulose

Chen, Pan 13 June 2013 (has links)
Les propriétés structurales de quatre types de cellulose cristalline (Iα, Iβ, II et IIII), incluant détails structuraux du coeur cristallin et des surfaces, comportement thermique, propriétés mécaniques et inter-conversions allomorphiques, ont été étudiées par des simulations de dynamique moléculaire (MD). Alors que la dynamique moléculaire est supposée reproduire correctement le monde réel, je me suis rendu compte que les paramètres des mailles cristallines élémentaires ainsi que la transition de phase induite par la température ne sont pas reproduites avec une précision satisfaisante. Dans l'objectif de rendre la modélisation plus fiable à compléter les expériences, j'ai dans un premier temps identifié les origines du désaccord et dans un second temps proposé de meilleurs paramètres pour les champs de forces. En utilisant ces paramètres, les caractéristiques structurales des quatre allomorphes de la cellulose sont bien mieux reproduites. Finalement, j'ai utilisé ces paramètres optimisés afin de modéliser d'une façon plus fiable certaines propriétés des cristaux de cellulose : incluant propriétés de surface, liaisons hydrogènes et caractéristiques mécaniques clefs. / The structural and physical properties of four types of crystalline cellulose (Iα, Iβ, II and IIII), including the structural details of the bulk and at the surfaces, thermal behavior, mechanical properties as well as the allomorph conversion, were studied by molecular dynamics (MD) simulation. Although simulations are in principle designed to reproduce the real world, I realized that unit cell parameters or properties such as temperature-induced phase transition were not reproduced to the precision we expected. In order to make MD more reliable to complement experiments, I first identified the origin of those discrepancies and second I proposed improved force field parameters. By using the optimized parameters, the structural characteristics of the four cellulose allomorphs were better reproduced. Finally, I used these optimized parameters to provide more reliable estimates of some structural characteristics of cellulosic crystals, such as surface properties and hydrogen bonding patterns together with key mechanical properties.

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