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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.
391

Phosphorylation and subcellular localization of NMDA receptors : modulation by ethanol /

Alvestad, Rachel Marie. January 2005 (has links)
Thesis (Ph.D. in Pharmacology) -- University of Colorado, 2005. / Typescript. Includes bibliographical references (leaves 145-170). Free to UCDHSC affiliates. Online version available via ProQuest Digital Dissertations;
392

The effects of d-Cycloserine, an NMDA receptor agonist, on conditioned taste aversion learning

Davenport, Rachel A. Houpt, Thomas A. Unknown Date (has links)
Thesis (M.S.)--Florida State University, 2006. / Advisor:Thomas A. Houpt, Florida State University, College of Arts and Sciences, Dept. of Biological Science. Title and description from dissertation home page (viewed June 7, 2006). Document formatted into pages; contains vi, 37 pages. Includes bibliographical references.
393

An investigation into the neuroprotective effects of estrogen and progesterone in a model of homocysteine-induced neurodegeration /

Wu, Wing Man. January 2005 (has links)
Thesis (M. Sc. (Pharmacy))--Rhodes University, 2006.
394

Untersuchungen an Ziervögeln (Agapornis spp.) zur Verträglichkeit unterschiedlich hoher Vitamin-K3-Gehalte im Alleinfutter

Hupfeld, Carolin. Unknown Date (has links) (PDF)
Tierärztl. Hochsch., Diss., 2003--Hannover.
395

Mathematische Modellierung des MDEA-Absorptionsprozesses

Giesen, Ralf. Unknown Date (has links) (PDF)
Techn. Hochsch., Diss., 2004--Aachen.
396

Molecular simulation of the adsorption of organics from water

Yazaydin, Ahmet Ozgur. January 2007 (has links)
Thesis (Ph. D.)--Worcester Polytechnic Institute. / Keywords: Water; Adsorption; Molecular simulation; Nanoporous materials. Includes bibliographical references (p. 117-119).
397

Avaliação do potencial antinociceptivo de 5- trialometil- 4,5-diidro-1h- pirazol metil ésteres inéditos em camundongos / Evaluation of the antinociceptive effect of novel 5- trihalomethyl- 4,5- dihydro- 1h pyrazole methyl esteres in mice

Milano, Julie Maria 11 July 2008 (has links)
Pain is a common symptom in clinical practice and many advances have been observed in order to obtain more effective analgesic molecules with fewer side effects. The present study evaluated the antinociceptive potential of four novel pyrazoles: 3-methyl-5-trifluoromethyl-5-hydroxy-4,5-dihydro-1H-pyrazole methyl ester (MPF3), 4-methyl-5-trifluoromethyl-5-hydroxy-4,5-dihydro-1H-pyrazole methyl ester (MPF4), 3-methyl-5-trichloromethyl-5-hydroxy-4,5-dihydro-1H-pyrazole methyl ester (MPCl3), and 4-methyl-5-trichloromethyl-5-hydroxy-4,5-dihydro-1H-pyrazole methyl ester (MPCl4). The systemic administration of the compounds was effective for the inhibition of the nociception in chemical (formalin test, 0.03 -1.0 mmol/kg, i.p.) and thermal (hot-plate test, 0.1-1.0 mmol/kg, i.p.) models of pain. In addition, MPF4 also produced antinociception in models of inflammatory pain induced by Complete Freund s Adjuvant (CFA) or by incision procedure in paw of mice. The antinociceptive effect of MPF4 (1.0 mmol/kg, i.p.) was not reversed by yohimbine (0.15 mg/kg, i.p.) or p-chlorophenylalanine ethyl ester (PCPA; 300 mg/kg, i.p.), but by naloxone (2.0 mg/kg, i.p.), in both thermal and chemical nociception. Animals given MPF4 (1.0 mmol/kg, i.p.) daily for 8 days in a row, in contrast to morphine (5 mg/kg, i.p.), showed no tolerance to its antinociceptive effect or cross-tolerance with morphine. However, similarly to morphine (11 mg/kg, i.p.), MPF4 (1.0 mmol/kg, i.p.) reduced gastrointestinal transit in mice and its effect was reversed by naloxone (2.5 mg/kg, i.p.). Unlike indomethacin (0.1 mmol/kg, p.o.), MPF4 (1.0 mmol/kg, p.o.) did not induce gastric lesions in mice. The tested compounds did not impair locomotion in the mice as well. Taken together, the results demonstrate that these novel pyrazoline methyl esters evaluated may be promising prototypes of additional mild analgesics, which are therapeutically relevant. / A dor é um sintoma comum na prática clínica, por isso muitos avanços estão sendo realizados no sentido de obter moléculas analgésicas cada vez mais efetivas e com menos efeitos colaterais. Neste contexto, no presente estudo avaliou-se o potencial antinociceptivo de quatro pirazóis inéditos: 3- metil-5-hidroxi-5-trifluormetil-4,5-diidro- 1H-pirazol metil éster (MPF3), 4-metil-5-hidroxi-5-trifluormetil-4,5-diidro-1H-pirazol metil éster (MPF4), 3-metil-5-hidroxi-5-triclorometil-4,5-diidro-1H-pirazol metil éster (MPCl3) e 4-metil-5-hidroxi-5-triclorometil-4,5-diidro-1H-pirazol metil éster (MPCl4). A administração sistêmica dos compostos foi efetiva em inibir a nocicepção em modelos de dor induzida por estímulo nocivo químico (teste da formalina, 0,03-1,0 mmol/kg, i.p.) e térmico (teste da placa-quente, 0,1-1,0 mmol/kg, i.p.). Em adição, MPF4 produziu antinocicepção em modelos de dor inflamatória causada por Adjuvante Completo de Freund (ACF) ou por incisão na pata de camundongos. O efeito antinociceptivo de MPF4 (1,0 mmol/kg, i.p.) não foi revertido pelo prétratamento dos animais com ioimbina (0,15 mg/kg, i.p.) ou p-clorofenilalanina etil éster (PCPA; 300 mg/kg, i.p.), mas sim, por naloxona (2,0 mg/kg, i.p.), tanto na nocicepção térmica quanto na nocicepção química. O tratamento dos animais durante um período de 8 dias consecutivos com MPF4 (1,0 mmol/kg, i.p), ao contrário daqueles tratados com morfina (5,0 mg/kg, i.p.), não desenvolveram tolerância antinociceptiva nem tolerância cruzada com os animais tolerantes à morfina. Porém, similar ao opióide morfina (11 mg/kg, i.p.), MPF4 (1,0 mmol/kg, i.p) inibiu o trânsito gastrintestinal de camundongos, sendo este efeito revertido por naloxona (2,5 mg/kg, i.p.). Além disso, diferente de indometacina (0,1 mmol/kg, v.o.), MPF4 (1,0 mmol/kg, v.o.) não induziu lesão gástrica em camundongos. Nenhum dos compostos testados causou alteração na atividade locomotora dos camundongos. Estes achados sugerem que os novos pirazoline metil ésteres avaliados parecem ser promissores para o desenvolvimento de novas drogas analgésicas terapeuticamente relevantes.
398

Processamento e caracteriza??o de comp?sitos Poli(METACRILATO DE METILA)/S?lica (PMMA/SiO2)

Silva, Erik dos Santos 05 April 2013 (has links)
Made available in DSpace on 2014-12-17T14:07:08Z (GMT). No. of bitstreams: 1 ErikSS_DISSERT.pdf: 3248804 bytes, checksum: 7241bc799da79c157edae8da7a7966cc (MD5) Previous issue date: 2013-04-05 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Currently the search for new materials with properties suitable for specific applications has increased the number of researches that aim to address market needs. The poly (methyl methacrylate) (PMMA) is one of the most important polymers of the family of polyacrylates and polymethacrylates, especially for its unique optical properties and weathering resistance, and exceptional hardness and gloss. The development of polymer composites by the addition of inorganic fillers to the PMMA matrix increases the potential use of this polymer in various fields of application. The most commonly used inorganic fillers are particles of silica (SiO2), modified clays, graphite and carbon nanotubes. The main objective of this work is the development of PMMA/SiO2 composites at different concentrations of SiO2, for new applications as engineering plastics. The composites were produced by extrusion of tubular film, and obtained via solution for application to commercial PMMA plates, and also by injection molding, for improved the abrasion and scratch resistance of PMMA without compromising transparency. The effects of the addition of silica particles in the polymer matrix properties were evaluated by the maximum tensile strength, hardness, abrasion and scratch resistance, in addition to preliminary characterization by torque rheometry and melt flow rate. The results indicated that it is possible to use silica particles in a PMMA matrix, and a higher silica concentration produced an increase of the abrasion and scratch resistance, hardness, and reduced tensile strength / Atualmente a busca por novos materiais com propriedades adequadas para aplica??es espec?ficas vem aumentando o n?mero de pesquisas que visam suprir as necessidades do mercado. O poli(metacrilato de metila) (PMMA) ? um dos pol?meros mais importantes da fam?lia dos poliacrilatos e polimetacrilatos, principalmente pelas suas inigual?veis propriedades ?pticas e resist?ncia ?s intemp?ries, al?m de excepcional dureza e brilho. O desenvolvimento de comp?sitos polim?ricos por meio da adi??o de cargas inorg?nicas ? matriz de PMMA aumenta o potencial de uso deste pol?mero em diferentes ?reas de aplica??o. Dentre as cargas inorg?nicas mais utilizadas, podem-se destacar as part?culas de s?lica (SiO2), argilas modificadas, grafite e nanotubos de carbono. O objetivo principal deste trabalho ? o desenvolvimento de comp?sitos PMMA/SiO2, em diferentes concentra??es, para novas aplica??es como pl?stico de engenharia. Os comp?sitos foram produzidos por meio de extrus?o de filme tubular, e obtidos via solu??o, para aplica??o em chapas de PMMA comercial, e tamb?m por moldagem por inje??o, buscando o aumento da resist?ncia ? abras?o e ao risco do PMMA, sem comprometer a transpar?ncia. Os efeitos causados pela adi??o das part?culas de s?lica nas propriedades da matriz polim?rica foram avaliados atrav?s da resist?ncia m?xima ? tra??o, dureza, resist?ncia ? abras?o e ao risco, al?m das caracteriza??es preliminares por reometria de torque e ?ndice de fluidez. Os resultados indicaram que ? poss?vel utilizar part?culas de s?lica em uma matriz de PMMA, e que uma maior concentra??o de s?lica promoveu um aumento da resist?ncia ? abras?o e ao risco, dureza, e reduziu a resist?ncia m?xima ? tra??o
399

Efeito de argilas organof?licas na estrutura e propriedades de nanocomp?sitos de poli(metacrilato de metila)

Rodrigues, Lourdes Aparecida Ribeiro 17 May 2013 (has links)
Made available in DSpace on 2014-12-17T14:07:18Z (GMT). No. of bitstreams: 1 LourdesARR_TESE.pdf: 12458480 bytes, checksum: 0efd4ff8bfb0c0bf6bcd3c18e449a690 (MD5) Previous issue date: 2013-05-17 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Nacomposites of polymers and lamellar clayminerals, has generated high scientific and technological interest, for having mechanical properties and gas barriers differentiated of polymers and conventional composites. In this work, it was developed nanocomposites by single screw extruder and injection, utilizing commercial raw material, with the goal to investigate the quality of new developed materials. It was evaluated the influence of the content and the kind of clay in the structure and in the nanocomposites properties. It was used regular and elastomeric poly (methyl methacrylate) (Acrigel LEP 100 and Acrigel ECP800) and six montmorillonites (Cloisite 10A, 11B, 15A, 20A, 25A e 30B) at the concentration of 1% e 3% in weight. The nanocomposites were characterized by X-ray diffraction (XRD), thermal gravimetric analysis (TGA), transmission electron microscopy (TEM), colorimetric, optical transparency, flexural and tensile tests, Rockwell hardness and esclerometry. It was founded that is possible to obtain intercalated and exfoliated nanocomposites PMMA/MMT, and the top results was obtained in the materials with 1%in clay weight organophilizated with 2M2HT (Cloisite 15A and 20A) presented intercalate and hybrid morphology (exfoliated and flocullated). The ones that was produced with organophilizated clay with 2MHTL8 (Cloisite 30B) had excellent visual quality, but the majority presented hybrid morphology. In the materials processed with organophilizated clay with MT2ETOH (Cloisite 30B), there were color change and loss of transparency. It occurs improvement in a few mechanical properties, mainly in the materials produced with PMMA elastomeric (Acrigel ECP800), being more significant, the increase in the resistance to stripping in those nanocomposites / Nanocomp?sitos de pol?meros e argilominerais lamelares t?m gerado alto interesse cient?fico e tecnol?gico por possu?rem propriedades mec?nicas e de barreira ? g?s diferenciadas de pol?meros e de comp?sitos convencionais. Neste trabalho, foram desenvolvidos nanocomp?sitos por meio de extrusora monorosca e injetora, utilizando mat?rias-primas comerciais, com a finalidade de investigar a qualidade dos novos materiais desenvolvidos. Foi avaliada a influ?ncia do teor e do tipo de argila na estrutura e nas propriedades dos nanocomp?sitos. Foram usados PMMA comum e elastom?rico (Acrigel? LEP100 e Acrigel? ECP800) e seis argilas montmorilonitas (Cloisite? 10A, 11B, 15A, 20A, 25A e 30B) nas concentra??es de 1% e 3% em peso. Os nanocomp?sitos foram caracterizados por difra??o de raios X (DRX), termogravimetria (TGA), microscopia eletr?nica de transmiss?o (MET), colorimetria, transpar?ncia ?ptica, ensaios de tra??o uniaxial, flex?o, dureza Rockwell e esclerometria. Constatou-se que ? poss?vel obter nanocomp?sitos PMMA/MMT intercalados e esfoliados, sendo os melhores resultados obtidos nos materiais processados com 1% em peso de argilas organofilizadas com 2MBHT (Cloisite? 10A e 11B). Materiais produzidos com argilas organofilizadas com 2M2HT (Cloisite? 15A e 20A) apresentaram morfologia intercalada e h?brida (esfoliada e floculada). J? os produzidos com argilas organofilizadas com 2MHTL8 (Cloisite? 25A) tiveram excelente qualidade visual, por?m a maioria apresentou morfologia h?brida. Nos materiais processados com argilas organofilizadas com MT2ETOH (Cloisite? 30B) houve altera??o na cor e perda da transpar?ncia. Houve melhoria em algumas propriedades mec?nicas, principalmente nos materiais produzidos com PMMA elastom?rico (Acrigel? ECP800), sendo mais significativo, o aumento na resist?ncia ao riscamento nesses nanocomp?sitos
400

Classificação e eficiência de materiais e de vestimentas de proteção no trabalho com agrotóxico /

Francischini, Letícia Ane Sizuki Nociti. January 2009 (has links)
Orientador: Joaquim Gonçalves Machado Neto / Banca: Maurício Leite de Oliveira / Banca: Manoel Lima de Menezes / Banca: Núbia Maria Correia / Banca: Claudinei da Cruz / Resumo: No Brasil, os CAs são emitidos por meio de um termo de responsabilidade técnica, sem avaliação de eficiência e vida útil. Os objetivos deste trabalho foram: 1) Quantificar a repelência, retenção e penetração em sete materiais hidrorrepelentes para o fungicida tiofanato metílico e em oito para herbicida glifosato; 2) Classificar os materiais hidrorrepelentes quanto à repelência e à penetração do fungicida tiofanato metílico e do herbicida glifosato; 3) Quantificar a permeação do fungicida tiofanato metílico e do herbicida glifosato em seis materiais impermeáveis; 4) Classificar os materiais impermeáveis quanto à permeação do fungicida tiofanato metílico e do herbicida glifosato; 5) Avaliar a eficiência de dois conjuntos hidrorrepelentes sem uso e ao longo de 30 usos e lavagens no controle da exposição dérmica de tratoristas em pulverizações de agrotóxicos em cultura de citros e de aplicadores de herbicidas em pósemergência em cana-de-açúcar. Quanto a repelência ao tiofanato metílico na formulação diluída, dos sete materiais avaliados, apenas um foi classificado como 2 pela ISO 16602 e na formulação pura todos foram classificados como 2 ou 3. Para a penetração todos foram classificados como 3. Para o glifosato os oito materiais avaliados foram classificados como 3 nas formulações diluída e pura quanto a repelência e penetração. Os seis materiais foram menos permeáveis ao tiofanato metílico na formulação diluída do que na pura. Para o glifosato diluído o material pvc foi permeável, o tychem SL e QC foram impermeáveis e o polipropileno laminado, aluminizado e tyvek foram permeáveis. Os dois conjuntos hidrorrepelentes avaliados no campo, sem uso e com 5, 10, 20 e 30 usos e lavagens controlaram mais de 90% da exposição dérmica dos tratoristas de pulverizador de arrasto tratorizado de jato transportado e dos aplicadores usando pulverizadores costais manuais. / Abstract: In Brazil, CAs are issued through a responsible technical term, without its efficient evaluation or lifespan. Thus, the objectives of this study were: 1) Quatify the repellency, the retention and the penetration in seven hydrorrepellent materials to methyl thiophanate fungicide and eight to glyphosate herbicide; 2) Classify the hidrorrepellent materials as for the repellency and the penetration of the methyl thiophanate fungicide and the glyphosate herbicide; 3) Quantify the permeability of the methyl thiophanate fungicide and the glyphosate herbicide in six impermeable materials; 4) Classify the impermeable materials as for the permeability of the methyl thiophanate fungicide and the glyphosate herbicide; 5) The evaluate the efficiency of the two-set protecting hydrorrepellent without use clothing and through 30 wearings and washings to control the dermal exposure of the orchard sprayer tractor driving of crop protection products in citrus crop and back pack sprayer of herbicides in post-emergency sugar cane crop. As for the repellency to the methyl thiophanate in diluted concentration, only one among the seven evaluated tissues, was classified as and in pure concentration all of them were evaluated as 2 or 3. All of them were classified as 3 for penetration. The eight tissues were classified as 3 in diluted and pure concentrations of glyphosate as for the repellency and penetration. The six evaluated materials were less permeable to methyl thiophanate diluted concentration than to the pure one. The pvc material was permeable to the diluted glyphosate, the tychem SL an QC were impermeable while the polypropylene rods, the aluminized and the tyvek were permeable. The two valuated hydrorrepellent sets in field, unused clothing and after 5, 10, 20 and 30 wearings and washing controlled more than 90% of dermal exposure of the orchard sprayer tractor driving and the back pack sprayers. / Doutor

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