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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.
101

Characterization of U2AF26, a paralog of the splicing factor U2AF35

Shepard, Jeremiah Brian. January 2004 (has links) (PDF)
Thesis (Ph. D.) -- University of Texas Southwestern Medical Center at Dallas, 2004. / Vita. Bibliography: 97-109.
102

Cellular level/distribution of [gamma]-secretase subunit nicastrin and its modulator p23 in the brain

Kodam, Anitha. January 2010 (has links)
Thesis (M.Sc.)--University of Alberta, 2010. / A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Master of Science, Department of Psychiatry. Title from pdf file main screen (viewed on February 14, 2010). Includes bibliographical references.
103

Diabetes in Latinas : depression, metabolic control and the roles of acculturation and social support

Olvera, Anna E. January 2005 (has links)
Thesis (M.S.) -- University of Texas Southwestern Medical Center at Dallas, 2005. / Vita. Bibliography: 104-117.
104

Identification of precursors present in fruit juice that lead to the production of guaiacol by Alicyclobacillus Acidoterrestris

Van der Merwe, Enette 03 1900 (has links)
Thesis (MSc Food Sc)--University of Stellenbosch, 2011. / ENGLISH ABSTRACT: Alicyclobacilli are endospore-forming, thermophilic, acidophilic bacteria (TAB) that survive the pasteurisation process and spoil acidic fruit juices through the production of the taint compound guaiacol. Guaiacol causes an undesirable odour with an unpleasant smoky, medicinal or phenolic-like taste. This thesis reports on the precursors, vanillin and vanillic acid metabolised to guaiacol by Alicyclobacillus spp. in fruit juice, the pathway of guaiacol production and the spoilage potential of contaminated fruit juices supplemented with these precursors. A high performance liquid chromatography method with UV-diode array detection (HPLC-DAD) was developed for the simultaneous detection and quantification of guaiacol and its precursors. Alicyclobacillus acidoterrestris FB2 was incubated at 45 °C for 7 d in Bacillus acidoterrestris (BAT) broth supplemented with ferulic acid, vanillin or vanillic acid. The cell concentrations were determined every 24 h and the concentration of the precursors and the production of guaiacol was determined using HPLC-DAD. The guaiacol production was also determined using the peroxidase enzyme colourimetric assay (PECA). Alicyclobacillus acidoterrestris produced guaiacol from vanillin and vanillic acid, confirming both vanillin and vanillic acid as precursors for guaiacol production by A. acidoterrestris FB2. Furthermore, a metabolic pathway directly from vanillin to guaiacol was identified in this study. However, guaiacol was not produced by A. acidoterrestris FB2 in the samples supplemented with ferulic acid and it is, therefore, not considered a direct precursor for guaiacol production by A. acidoterrestris. The spoilage potential of apple juice supplemented with either 10 mg L-1 or 100 mg L-1 vanillin or vanillic acid by A. acidoterrestris FB2 (106 cfu mL-1) was also evaluated. The production of guaiacol increased with the increase in vanillin or vanillic acid concentrations (in BAT broth and apple juice) indicating that the concentration of vanillin and vanillic acid present in fruit juice will influence the spoilage potential of the juice. Guaiacol concentrations in apple juice well above the best estimated threshold value of guaiacol for taste (0.24 – 2.00 μg L-1) and odour (0.50 - 2.32 μg L-1) was produced by A. acidoterrestris FB2 in the apple juice supplemented with 10 mg L-1 vanillin or vanillic acid. This indicates that fruit juice with a vanillin or vanillic acid concentration as low as 10 mg L-1 has the potential to spoil if the juice is contaminated with A. acidoterrestris. The concentrations of vanillin and vanillic acid in different fruit juices can be used to indicate if a specific fruit juice is susceptible to guaiacol spoilage by Alicyclobacillus spp. In the development of juice products and different blends of fruit juices, special care must be taken not to concentrate the amount of vanillin and vanillic acid present in the fruit juices. / AFRIKAANSE OPSOMMING: Alicyclobacilli is endospoor-vormende, termofiliese, asidofiliese bacterie (TAB) wat die pasteurisasie proses oorleef en suur vrugtesappe bederf met die produksie van ‘n taint komponent guaiakol. Guaiakol veroorsaak ‘n ongewensde reuk en onaangename rookagtige, medisinale of fenoliese smaak. Hierdie tesis doen verslag oor die voorloper komponente, vanillien en vanilliensuur in vrugtesappe wat gemetaboliseer word na guaiakol deur Alicyclobacillus spesies, die padweg van guaiakol produksie en die bederfbaarheid van gekontamineerde vrugtesap aangevul met hierdie voorloper komponente. ‘n Hoëprestasie vloeistof chromatografie metode met UV-deteksie (skanderend) (HPVC) is ontwikkel vir die gesamentlike deteksie en kwantifisering van guaiakol en die voorloper komponente. Alicyclobacillus acidoterrestris FB2 is geïnkubeer by 45 °C vir 7 d in Bacillus acidoterrestris (BAT) medium aangevul met feruliensuur, vanillien of vanilliensuur. Die sel konsentrasies is elke 24 h bepaal en die aangevulde komponente en die geproduseerde guaiakol is bepaal deur van HPVC gebruik te maak. Die guaiakol konsentrasies is ook bepaal deur van die peroksidase ensiem kolorimetriese bepaling (PEKB) gebruik te maak. Alicyclobacillus acidoterrestris het guaiakol geproduseer vanaf vanillien en vanilliensuur, dus is beide vanillien en vanilliensuur bevestig as voorlopers van guaiakol produksie deur A. acidoterrestris FB2. A padweg direk van vanillien na guaiakol is in hierdie studie geïdentifiseer. Guaiakol is nie geproduseer deur A. acidoterrestris FB2 in the monsters wat met feruliensuur aangevul is nie en feruliensuur is dus nie ‘n direkte voorloper van guaiakol produksie deur A. acidoterrestris. Die bederf potensiaal van appelsap aangevul met 10 mg L-1 of 100 mg L-1 vanillien of vanilliensuur deur A. acidoterrestris (106 kve mL-1) is ook geëvalueer. Die produksie van guaiakol het toegeneem met die toename in vanillien of vanilliensuur konsentrasies (in beide BAT en appelsap) wat aandui dat die konsentrasie vanillien en vanilliensuur teenwoordig in vrugtesap die bederfbaarheid van die sap sal beïvloed. Guaiakol konsentrasies in appelsap hoog bo die drumpel waardes van guaiacol vir smaak (0.24 – 2.00 μg L-1) en reuk (0.50 - 2.32 μg L-1) is geproduseer deur A. acidoterrestris FB2 in die appelsap monsters aangevul met 10 mg L-1 vanillien of vanilliensuur. Hierdie verskynsel dui aan dat vrugtesap met ‘n vanillien of vanilliensuur konsentrasies van so laag as 10 mg L-1 die potensiaal het om te bederf indien die sap gekontamineer is met A. acidoterrestris. Die konsentrasies van vanillien en vanilliensuur in verskillende vrugtesappe kan gebruik word om aan te dui of ‘n spesifieke vrugtesap ‘n hoë risiko het vir guaiakol bederf deur Alicyclobacillus spesies. Tydens die ontwikkeling van vrugtesap produkte en verskillende mengsels van vrugtesappe moet seker gemaak word dat die hoeveelhede vanillien en vanilliensuur in die sappe nie gekonsentreer word nie.
105

Caracterização de filmes finos de YBa2Cu3O7-x e La0.7Ca0.3MnO3 produzidos via síntese química

Santos, Cássio Morilla dos [UNESP] 09 March 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:23:29Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-03-09Bitstream added on 2014-06-13T19:09:18Z : No. of bitstreams: 1 santos_cm_me_bauru.pdf: 3402403 bytes, checksum: 93b5430687fb5b726426e9016204d6ce (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Este trabalho teve como objetivos a preparação e caracterização de filmes finos de YBa2Cu3O.7-x e La0.7Ca0.3MnO3 depositados sobre substratos de níquel metálico, silício, e substratos cerâmicos de MgO, SrTiO.3. As análises realizadas tiveram como objetivos o estudo da formação da fase, e a determinação do comportamento de condução elétrica e das propriedades magnéticas dos filmes finos. Nas deposições realizadas sobre substratos de níquel foi utilizada uma camada intermediária de Y.2O.3, para posterior deposição de YBa.2Cu.3O.7-x. As soluções precursoras dos filmes foram obtidas através do método dos precursores poliméricos, com a inclusão do ácido etilenodiaminotetraacético (EDTA) como agente complexante. As deposições ocorreram através da técnica Spin-Coating. As análises realizadas através da Espectroscopia de Fotoelétrons de Raios X (XPS) e Difração de Raios X (XRD) auxiliaram, na identificação dos elementos químicos presentes nos filmes finos, e a verificação da formação das fases cristalográficas desejadas. Estas técnicas permitiram comprovar a eficácia da camada intermediária (buffer layer) de Y.2O.3 utilizada para a deposição de YBa.2Cu.3O.7-x sobre substratos de níquel metálico, e comprovar a necessidade de uma camada buffer layer para a obtenção de filmes de YBa.2Cu.3O.7-x depositado sobre substrato de silício. Assim como na deposição realizada sobre substrato de níquel, foi verificada também a boa formação das fases desejadas sobre os substratos cerâmicos. As análises de condução elétrica e das propriedades magnéticas demonstraram a característica supercondutora dos filmes de YBa.2Cu.3.O.7-x depositados sobre substratos de níquel metálico, MgO e SrTiOI.3, e... / This paper aimed at preparing and characterizing YBa2Cu3O.7-x e La0.7Ca0.3MnO3 and thin films, deposited on metallic nickel substrates, silicon and MgO, SrTiO.3 and LaAIO.3 ceramic substrates. The analyses performed had as objectives to study the phase formation and to determine the electric conduction behavior and the magnetic properties of the thin films. In the depositions perfomed on nickel substrates, a YBa.2Cu.3O.7-x deposition. The precursory solutions of the films were obtained by means of the polymeric precursor method, with the inclusion of the ethylenediaminotetra acetic acid (EDTA), as complexant agent. The depositions occurred through the Spin-coating technique. The analyses performed by means of the X-ray Photoelectron Spectroscopy (XPS) and X-ray Diffraction (XRD) aided in the identification of the chemical elements present in the thin films and in the verification of the formation of the desired crystallographic phases. Such techniques allowed for confirming the Y.2O.3 buffer layer efficacy, utilized to the YBa.2Cu.3O.7-x deposition on metallic nickel substrates, and for confirming the need of a buffer layer in order to obtain the YBa.2Cu.3O.7-x films deposited on the silicon substrate. As in the deposition performed on the nickel substrate, it was also verified the good formation of the desired phases on the ceramic substrates. The analyses on electrical conduction and magnetic properties demonstrated the superconducting characteristic of the YBa.2Cu.3O.7-x films deposited on metallic nickel substrates, MgO and SrTiO.3, as well as the magnetic characteristic of the La.0.7Ca.0.3MNO.3 film deposited on the silicon substrate. The analyses performed by means of Scanning Electron Microscopy (SEM) showed a better ...(Complete abstract, click electronic address below)
106

Otimização das condições de síntese de amostras cerâmicas do composto Y'Ba IND. 2''Cu IND. 3''O IND. 7'-δ através do Método Pechini

Amaral, Delton [UNESP] 30 November 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:23:30Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-11-30Bitstream added on 2014-06-13T20:50:24Z : No. of bitstreams: 1 amaral_d_me_bauru.pdf: 3079675 bytes, checksum: f8511d65e696a1107b5e2fc901da1073 (MD5) / Materiais cerâmicos supercondutores apresentam propriedades importantes para aplicações tecnológicas. A principal propriedade, resposta magnética depende fortemente da rota de síntese, método de processamento, e principalmente da estequiometria do material. No presente trabalho, foram estudadas algumas variações envolvidas nas condições de síntese de pós cerâmicos do composto Y'Ba IND. 2''Cu IND. 3''O IND. 7'-δ sintetizados do método Pechini. Com a finalidade de verificar-se amostras com o menor teor da fase secundária Carbonato de Bário (Ba'CO IND. 3'), utilizou-se as variações em pH em 3, 7 e 10 em amostras com e sem a utilização do ácido etilenodiaminotetracético (EDTA) na síntese do precursos polimérico. Buscou-se também melhor compreender os processos físico-químicos presentes nas diferentes etapas da preparação das amostras. Ainda nesse estudo, fez-se tratamentos térmicos em 400 °C, 700 °C e 900 °C para uma avaliação qualitativa das partículas. Foi utilizado como fonte de cátions, óxidos de ítrio e cobre, além de carbonato de bário. Como agente complexante o ácido cítrico (AC) e como agente polimerizante e etilenoglicol (EG). A resina polimérica foi caracterizada usando-se análise térmica diferencial (DTG), Termogravimetria (TG) com acoplamento à espectrofotometria no Infravermelho (IRFT) e Calorimetria Exploratória Diferencial (DSC). Tais caracterizações foram feitas de forma a relacionar a estrutura, condições de síntese e fenômenos que ocorrem em cada intervado de temperatura. O produto da pirólise da resina, denominado de puff, foi desaglomerado e calcinado a diferentes temperaturas, sob atmosfera ambiente, permitindo-se o acompanhamento da evolução das fases cristalográficas por difração de Raio-X (DRX), sendo a morfologia do pós, verificada por microscopia eletrônica de varredura (MEV). Por meio dos dados obtidos... / Ceramic superconducting materials present significant properties for technological applications. These properties strongly depend on the synthesis routes, processing methods, and mainly on the chemical stoichiometry of the prepared compounds. In this work some steps and variations on the synthesis conditions on Y'Ba IND. 2''Cu IND. 3''O IND. 7'-δ (YBCO) were studied by using the Sol-Gel technique, known as the Pechini method. The influence of pH and the use of etilenodiaminotetracetic acid (EDTA) in the synthesis of the YBCO phase, as well as a possible formation of Ba'CO IND. 3, as a secondary undesirable phase were tested. Oxides and carbonates were used as metallic salts, acid citric (CA) and the ethylene-glycol (EG) were used as complexing agent and polymerization agent, respectively. The polymeric resin was characterized by differential thermal analysis (DTA/DSC) and thermogravimetric analysis (TG) associated with infrared spectroscopy (IRFT), trying to relate the polymer structure and the synthesis conditions for each temperature. After that, the polymeric gel was pyrolezed in a temperature of 200 °C, ground and heat-treated under different temperatures, allowing the study of the crystallographic phase evolution by using X-ray diffraction (XRD). The powder morphology was also analyzed by means of scanning electron microscopy (SEM). The obtained results indicated that the samples prepared using pH close to 7, without the use of EDTA under a temperature of 900 °C, presented smaller amount of secondary phases.
107

S?ntese de pigmentos cer?micos inorg?nicos nanom?tricos e encapsulados com estrutura core-shell pela rota dos precursores polim?ricos

Mac?do, D?rcia S?mia Santos Moura de 09 April 2012 (has links)
Made available in DSpace on 2014-12-17T14:07:02Z (GMT). No. of bitstreams: 1 DarciaSSMM_DISSERT.pdf: 2144091 bytes, checksum: 373e58cf1ee08b2c45a550ad627238d6 (MD5) Previous issue date: 2012-04-09 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The present work has as objective the development of ceramic pigments based in iron oxides and cobalt through the polymeric precursor method, as well as study their characteristics and properties using methods of physical, chemical, morphological and optical characterizations.In this work was used iron nitrate, and cobalt citrate as precursor and nanometer silica as a matrix. The synthesis was based on dissolving the citric acid as complexing agent, addition of metal oxides, such as chromophores ions and polymerization with ethylene glycol. The powder obtained has undergone pre-ignition, breakdown and thermal treatments at different calcination temperatures (700 ?C, 800 ?C, 900 ?C, 1000 ?C and 1100 ?C). Thermogravimetric analyzes were performed (BT) and Differential Thermal Analysis (DTA), in order to evaluate the term decomposition of samples, beyond characterization by techniques such as BET, which classified as microporous materials samples calcined at 700 ? C, 800 ? C and 900 ? C and non-porous when annealed at 1000 ? C and 1100 ? C, X-ray diffraction (XRD), which identified the formation of two crystalline phases, the Cobalt Ferrite (CoFe2O4) and Cristobalite (SiO2), Scanning Electron Microscopy (SEM) revealed the formation of agglomerates of particles slightly rounded;and Analysis of Colorimetry, temperature of 700 ?C, 800 ?C and 900 ?C showed a brown color and 1000 ?C and 1100 ?C violet / O presente trabalho tem como objetivo o desenvolvimento de pigmentos cer?micos a base de ?xidos de ferro e cobalto atrav?s do m?todo dos precursores polim?ricos, bem como o estudo de suas caracter?sticas e propriedades atrav?s de m?todos de caracteriza??es f?sicas, qu?micas, morfol?gicas e ?pticas. Neste trabalho foi utilizado nitrato de ferro e citrato de cobalto como precursores e s?lica nanom?trica como matriz. A s?ntese foi baseada na dissolu??o do ?cido c?trico, como agente complexante; adi??o dos ?xidos met?licos, como ?ons crom?foros e polimeriza??o com etileno glicol. O P? obtido passou por pr?-calcina??o, desagrega??o e tratamentos t?rmicos em diferentes temperaturas de calcina??o (700 ?C, 800 ?C, 900 ?C, 1000 ?C e 1100 ?C). Foram feitas An?lises de Termogravimetria (TG) e An?lise T?rmica Diferencial (DTA), a fim de se avaliar a termodecomposi??o das amostras, al?m de caracteriza??es por t?cnicas como BET, que classificou como materiais microporosos as amostras calcinadas a 700 ?C, 800 ?C e 900 ?C e n?o porosos quando calcinados a 1000 ?C e 1100 ?C; Difra??o de Raios-X (DRX), que identificou a forma??o de duas fases cristalinas, a Ferrita de Cobalto (CoFe2O4) e a Cristobalita (SiO2); Microscopia Eletr?nica de Varredura (MEV), que revelou a forma??o de aglomerados de part?culas ligeiramente arredondadas; e an?lise de colorimetria na regi?o do UV-Vis?vel, verificando a varia??o e o potencial de cromaticidade do pigmento que a temperaturas de 700 ?C, 800 ?C e 900 ?C apresentou a cor marrom e a 1000 ?C e 1100 ?C a cor violeta
108

Caracterização de filmes finos de YBa2Cu3O7-x e La0.7Ca0.3MnO3 produzidos via síntese química /

Santos, Cássio Morilla dos. January 2007 (has links)
Orientador: Paulo Noronha Lisboa Filho / Banca: Margarida Juri Saeki / Banca: Valmor Roberto Mastelaro / O Programa de Pós-Graduação em Ciência e Tecnologia de Materiais, PosMat, tem caráter institucional e integra as atividades de pesquisa em materiais de diversos campi da Unesp / Resumo: Este trabalho teve como objetivos a preparação e caracterização de filmes finos de YBa2Cu3O.7-x e La0.7Ca0.3MnO3 depositados sobre substratos de níquel metálico, silício, e substratos cerâmicos de MgO, SrTiO.3. As análises realizadas tiveram como objetivos o estudo da formação da fase, e a determinação do comportamento de condução elétrica e das propriedades magnéticas dos filmes finos. Nas deposições realizadas sobre substratos de níquel foi utilizada uma camada intermediária de Y.2O.3, para posterior deposição de YBa.2Cu.3O.7-x. As soluções precursoras dos filmes foram obtidas através do método dos precursores poliméricos, com a inclusão do ácido etilenodiaminotetraacético (EDTA) como agente complexante. As deposições ocorreram através da técnica Spin-Coating. As análises realizadas através da Espectroscopia de Fotoelétrons de Raios X (XPS) e Difração de Raios X (XRD) auxiliaram, na identificação dos elementos químicos presentes nos filmes finos, e a verificação da formação das fases cristalográficas desejadas. Estas técnicas permitiram comprovar a eficácia da camada intermediária (buffer layer) de Y.2O.3 utilizada para a deposição de YBa.2Cu.3O.7-x sobre substratos de níquel metálico, e comprovar a necessidade de uma camada buffer layer para a obtenção de filmes de YBa.2Cu.3O.7-x depositado sobre substrato de silício. Assim como na deposição realizada sobre substrato de níquel, foi verificada também a boa formação das fases desejadas sobre os substratos cerâmicos. As análises de condução elétrica e das propriedades magnéticas demonstraram a característica supercondutora dos filmes de YBa.2Cu.3.O.7-x depositados sobre substratos de níquel metálico, MgO e SrTiOI.3, e ...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This paper aimed at preparing and characterizing YBa2Cu3O.7-x e La0.7Ca0.3MnO3 and thin films, deposited on metallic nickel substrates, silicon and MgO, SrTiO.3 and LaAIO.3 ceramic substrates. The analyses performed had as objectives to study the phase formation and to determine the electric conduction behavior and the magnetic properties of the thin films. In the depositions perfomed on nickel substrates, a YBa.2Cu.3O.7-x deposition. The precursory solutions of the films were obtained by means of the polymeric precursor method, with the inclusion of the ethylenediaminotetra acetic acid (EDTA), as complexant agent. The depositions occurred through the Spin-coating technique. The analyses performed by means of the X-ray Photoelectron Spectroscopy (XPS) and X-ray Diffraction (XRD) aided in the identification of the chemical elements present in the thin films and in the verification of the formation of the desired crystallographic phases. Such techniques allowed for confirming the Y.2O.3 buffer layer efficacy, utilized to the YBa.2Cu.3O.7-x deposition on metallic nickel substrates, and for confirming the need of a buffer layer in order to obtain the YBa.2Cu.3O.7-x films deposited on the silicon substrate. As in the deposition performed on the nickel substrate, it was also verified the good formation of the desired phases on the ceramic substrates. The analyses on electrical conduction and magnetic properties demonstrated the superconducting characteristic of the YBa.2Cu.3O.7-x films deposited on metallic nickel substrates, MgO and SrTiO.3, as well as the magnetic characteristic of the La.0.7Ca.0.3MNO.3 film deposited on the silicon substrate. The analyses performed by means of Scanning Electron Microscopy (SEM) showed a better ...(Complete abstract, click electronic address below) / Mestre
109

Dietary impacts on intestinal microbial community and cardiovascular diseases

Atwal, Navtej 01 November 2017 (has links)
OBJECTIVE: Chapter 1: Investigate the impact that trimethylamine N-oxide (TMAO), dietary contribution of short chain fatty acids (SCFAs), and role of bile acids has on cardiovascular health and disease. Chapter 2: Evaluate the association between intakes of dietary protein from both animal and plant sources on lipid profile changes. METHODS: Chapter 1: Literature review using PubMed and EMBASE to search for published studies for dietary intake or supplementation impact on TMAO or its precursors and their role in the development or prevention of cardiovascular diseases. Chapter 2: Framingham Offspring Study, prospective cohort study using statistical methods to investigate the changes in lipid profiles with dietary animal and plant protein. PUBLISHED STUDIES/RESULTS: Chapter 1: The increased risk of cardiovascular diseases (CVD) correlates with increasing levels of circulating levels of TMAO. The risk of CVD in animal and human studies have shown to be distinct in groups with and without CVD, leading to either beneficial or adverse effects from the consumption of dietary phosphatidylcholine, choline, betaine, carnitine, or intact TMAO. A Western dietary approach has been linked with the development of dyslipidemia whereas, adherence to a Mediterranean diet reduces the risk of major CVD events. The dietary precursors involved in TMA production by the gut microbiota then respectively to TMAO through hepatic enzyme FMO3 provide both beneficial and detrimental effects. Mechanisms of action for TMAO on CVD risk involves changes associated with cholesterol and sterol metabolism leading to foam cell formation, and enhancement of scavenger receptors, CD36 and scavenger receptor-A, on macrophages affects the rate of cholesterol influx and efflux. Choline derived in a dose-dependent manner from eggs improves cardiometabolic biomarkers with no changes in fasting TMAO. Further, choline from eggs also increases the lipoprotein particle size for both HDL-cholesterol and LDL-cholesterol increasing the rate of reverse cholesterol transport (RCT). Betaine concentrations in humans are associated with health outcomes based on an individual’s overall systemic health at baseline. Supplementation with L-carnitine produced favorable effects in lean subjects compared to obese subjects, improved cardiometabolic status in patients with myocardial infarction, and improved lipid profiles among individuals with prevalent coronary heart disease (CAD). Fish consumption increases concentrations of TMAO due to its high levels of intact TMAO though, protective effects for CVD are obtained from fatty fish providing omega-3-fatty acids impacting positive changes in the lipid profiles. Antibiotic therapy suppresses the gut microbiota and eliminates the production of TMA from the dietary precursors that are required. Chapter 2: Men and women both showed a decreasing trend for LDL-cholesterol as the tertiles increased for animal protein intake. Plant protein intake showed a similar decreasing trend for LDL-cholesterol with increasing protein tertiles; however, men had inconsistency among the trend whereas women had a consistent decreasing trend. HDL-cholesterol content increases in males and females with both increasing tertiles for animal and plant protein, though plant protein presented much stronger effects when compared to animal protein. Log-transformed triglycerides were inversely associated with increasing animal protein intake, men revealing greater effects than females. Plant protein intake showed a stronger effect than animal protein intake in an increasing trend in the log of triglycerides over the 6 exams. Overall, total cholesterol content varied at each examination period, animal protein intake tertiles displayed decreased level of total cholesterol, there was a greater effect in men than women. Higher intake of plant protein had a similar trend to animal protein intake showing a decrease in the total cholesterol concentration. Women had a much greater effect in reducing total cholesterol with plant protein when compared to men. CONCLUSION: Chapter 1: Multiple human and animal trials addressed in the association between diet, dietary precursors, gut microbiota composition, and their derived metabolite TMAO on the presence or absence of CVD display contradictory results and identifies areas needing further study. Chapter 2: Regardless of the source of protein, the lipid profiles improved with the intake of either animal or plant protein as the protein intake was increased over the tertiles in each exam. The overall trend with increasing animal or plant protein intake led to decrease in LDL-cholesterol, log transformed triglycerides, and total cholesterol whereas, the HDL-cholesterol concentrations were increased. Men favored animal protein intake to show greater reductions in LDL-cholesterol and total cholesterol, whereas women favored plant protein. The increase in HDL-cholesterol concentration was stronger with the intake of plant protein in men and women. The changes in log transformed triglycerides were similar in men and women.
110

Families of metastable misfit layered compounds prepared by modulated elemental precursors and the resulting physical properties

Heideman, Colby Luke, 1979- 06 1900 (has links)
xix, 141 p. : ill. (some col.) A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. / The constant drive to improve material properties has recently led researchers towards metastable nanostructured materials, increasing the need for new synthetic pathways capable of rationally accessing targeted compounds. A method is demonstrated for using physical vapor deposition to create elementally modulated precursors targeting specific compounds. Controlling the modulation length scale of the precursor allows entire families of misfit layered compounds to be synthesized with atomic level control of the structure. Over 100 new misfit layered compounds were synthesized in the [(BiSe) 1.10 ] m (NbSe 2 ) n , [(PbSe) 1.10 ] m (NbSe 2 ) n , [(PbSe) 1.00 ] m (MoSe 2 ) n , and [(SnSe) 1.10 ] m (MoSe 2 ) n , families. The three-dimensional structures of these compounds are examined. These materials are shown to form turbostratically disordered sheets of transition metal dichalcogenide layers interwoven between blocks of rock salt layers. These layers have very small in-plane grain sizes on the order of 10 mn. The interfaces between these layers lack any epitaxial relationship and yet are atomically abrupt and indicate no strain present. The unique metastable structures lead to fascinating properties in these compounds. The turbostratic disorder leads to extremely low thermal conductivity perpendicular to the layering. Thermal conductivities as low as 0.07 W/m/K were measured. Because of the flexible chemistries, a wide range of electrical properties are accessible in these materials, with electrical conductivities ranging from metallic to semiconducting and carrier concentrations ranging from 10 17 to 10 21 cm -3 . Despite the small grain sizes, respectable mobilities have also been measured, up to 21 cm 2 V -1 s -1 . This work consists, in part, of previously published and coauthored material. / Committee in charge: James Hutchison, Chairperson, Chemistry; David Johnson, Advisor, Chemistry; David Tyler, Member, Chemistry; Geraldine Richmond, Member, Chemistry; Richard Taylor, Outside Member, Physics

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