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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.
21

Relação entre contagem total de linfócitos e contagem de células T CD4+ em pacientes soropositivos para HIV

Angelo, Ana Luiza Dias January 2005 (has links)
Submitted by Hiolanda Rêgo (hiolandarego@gmail.com) on 2016-07-27T15:42:04Z No. of bitstreams: 1 Dissertação_ICS_ Ana Luiza Dias Angelo.pdf: 1143787 bytes, checksum: 4f198dcfcd707a8f0ed1c85f8673c9cc (MD5) / Made available in DSpace on 2016-07-27T15:42:04Z (GMT). No. of bitstreams: 1 Dissertação_ICS_ Ana Luiza Dias Angelo.pdf: 1143787 bytes, checksum: 4f198dcfcd707a8f0ed1c85f8673c9cc (MD5) / CAPES / A contagem de células T CD4+ é o principal marcador imunológico usado para definir o momento adequado para início da terapia antiretroviral e profilaxia para infecções oportunistas em pacientes portadores do vírus HIV. Seu alto custo limita o uso desta técnica em muitos locais no mundo. O objetivo deste estudo foi avaliar a utilidade da TLC em substituir a contagem de células T CD4+ como marcador imunológico para detectar os pacientes com necessidade de profilaxia contra infecções oportunistas (CD4 < 200 cel/mm3), e aqueles com CD4 < 350 cel/mm3 (limite brasileiro que define AIDS). Nós analisamos a TLC e contagem de células T CD4 de 1174 pacientes infectados pelo HIV provenientes do HUPES durante o período de maio/2003 a setembro/2004. A contagem de células T CD4+ foi realizada por citometria de fluxo e a contagem total de linfócitos por contador hematológico automatizado. Foram analisadas um total de 1510 amostras. A contagem de células T CD4+ teve valor mínimo de 4 cel/mm3 e valor máximo de 2531 cel/mm3, TLC teve mínimo de 300 cel/mm3 e máximo de 6200 cel/mm3. O melhor valor de TLC, capaz de predizer CD4 < 200 cel/mm3, foi ≤ 1700 cel/mm3 (SE=76,3%; SPE=65,2%, NPV=93,1%), mas PPV de somente 31,1%. Resultados semelhantes foram encontrados para contagem de células T CD4+ < 350 cel/mm3, entretanto observou-se menor sensibilidade (SE= 59,4%, SPE=96,6%, PPV= 57,3% e NPV= 79,4%). Estes resultados indicam que apesar da forte associação existente entre TLC e contagem de células T CD4+, a contagem total de linfócitos não é um bom indicador da contagem de células T CD4+ em pacientes portadores do vírus HIV, mas pode ser um útil indicador para dispensar a realização da contagem de células T CD4+.
22

Desde Mao al TLC: Chile y la oportunidad China

Esteffan Cam, Gabriel 10 1900 (has links)
Memoria para optar al Título de Periodista / China es el motor de la reactivación mundial y el principal responsable del fantástico precio del cobre durante el año 2005, gran noticia para nuestro país. Con un crecimiento del producto interno bruto (PIB) de un 8% anual en el último decenio, la nación más poblada del globo comprendió que hay muchas cosas más allá de la Gran Muralla, y se abrió al mundo. Chile, con su política aperturista adoptada durante la dictadura militar, firmó desde 1991 Tratados de Libre Comercio (TLC) con Canadá, México, Centroamérica, la Unión Europea, la EFTA (Islandia, Liechtenstein, Noruega y Suiza) y Estados Unidos. En 2004, fue el turno de Corea del Sur. Ese fue el primer paso en Asia. Además, la diplomacia chilena rubricó Acuerdos de Complementación Económica (ACE) con todos los países latinoamericanos, el Mercosur. En septiembre de 2005, nuestro país tenía proyectos de TLC con India, Japón, el P4 (con Nueva Zelanda, Singapur y Brunei) y China.
23

Možnosti analytického stanovení volných mastných kyselin / The possibilities of assessment of free fatty acids

Hornáková, Miroslava January 2015 (has links)
This thesis deals with the determination of free fatty acids in natural and processed cheese. In the theoretical part the possibilities of extraction, fractionation and determination of lipid fractions, characterization of fatty acids and various methods of their determination are described, including the determination of free fatty acids. In the experimental part the selected method for determination of free fatty acids was optimized and partly validated; this method was then applied to samples of processed cheese analogues and natural Gouda type cheese. For extraction of lipids from the sample the method according to ČSN 0107 was selected, solid phase extraction (SPE) was used for separation of free fatty acids. The method according to ČSN EN ISO 5509, using methanol solution of potassium hydroxide, was applied for esterification, fatty acids methyl esters were determined by gas chromatography with FID detection.
24

Chemoenzymová synthesa antivirálních profarmak / Chemo-enzymatic synthesis of antiviral prodrugs

Tupec, Michal January 2015 (has links)
Lipases have been widely applied in the manufacture of food products and in some areas of the industry, nowadays they are used in synthetic organic chemistry catalyzing the hydrolytic/esterification reactions under very mild conditions in the field of protecting groups or enantiomer resolution. In this study, the commercial lipase from bacterium Pseudomonas fluorescens was immobilized using the sol-gel process into organosilicate materials with propyl, octyl or phenyl substituents. The highest hydrolytic activity was found in the enzyme on the octyl-derived carrier. The immobilized enzymes differ in their hydrolytic activities on 4-nitrophenyl esters of various lengths. Subsequent experiments revealed quite good pH stability of the enzymes in a buffer (incubations in pH 3 through pH 11), as well as good temperature stability in isooctane (incubations at up to 100 řC). The majority of organic solvents seem to have no substantial effect on the lipase activity. The biocatalytic properties were studied on a model compound from the group of the acyclic nucleoside analogues - 9-(2',3'-dihydroxypropyl)adenine (DHPA). It was found for example that the best acyl donors are vinyl esters, that the lipase shows a preference towards longer vinyl esters, that the reaction proceeds faster in non-polar solvents or that it...
25

El TLC con Estados Unidos a 10 años de su implementación

26 February 2019 (has links)
Evento realizado en el auditorio del Campus San Miguel de la Universidad Peruana de Ciencias Aplicadas. / Conferencia realizada en el marco del International Business Day UPC 2019. Evento en el cual se trataron temas relacionados al proceso de implementación del tratado de libre comercio (TLC) entre Perú y Estados Unidos así como su impacto luego de 10 años.
26

Molecular and bio-analytical characterisation as a means to understand genetic diversity within Kenyan Aspergillus flavus strains

Mitema, Alfred Ochieng 03 September 2018 (has links)
Toxigenic Aspergillus species produce mycotoxins that are carcinogenic, hepatotoxic and teratogenic immunosuppressing agents in both human and animals. Kenya frequently experiences outbreaks of aflatoxicosis with the worst occurring in 2004, which resulted in 125 deaths. This study sought to find possible reasons for frequent aflatoxicosis outbreaks in Kenya by isolating Aspergillus flavus strains from maize kernels sampled from different climatic regions of Kenya. Using diagonal transect random sampling, maize kernels were collected from Makueni, Homa Bay, Nandi, and Kisumu regions. The genetic diversity and variation among the isolates was examined by characterising the strains according to morphology, phenotype, vegetative compatible groups and molecular systematics. Selected atoxigenic and aflatoxigenic A. flavus isolates were also further analysed for aflatoxin production potential using quantitative real-time PCR and various bioanalytical techniques. The influence of the maize lines grown in Kisumu, Homa Bay, Nandi and Makueni region on A. flavus infection and aflatoxin production was also examined and served as the basis for an in vitro biocontrol assay. Out of 37 isolates identified, nitrate non-utilizing auxotroph’s complementation test revealed 20 vegetative compatibility groups. These groups were further designated using the prefix ʻʻKVCGʼʼ, where ʻʻKʼʼ represented Kenya and consequently assigned numbers 1 to 20 based on our findings. KVCG14 and KVCG15 had highest distribution frequency (n = 13; 10.8 %). The distribution of the L, S and S/L- morphotypes across the regions were 57 % (n = 21); 7 % (n = 3) and 36 % (n = 13) respectively. The phylogenetic analysis exhibited high diversity of A. flavus isolates from Makueni. ITS1 and ITS2 markers did not reveal significant information within intraspecies speciation of A. flavus. Furthermore, a unique isolate (KSM015) was identified that had characteristics of S-morphotype, but produced both aflatoxins B and G. Coconut agar medium (CAM) assay, TLC, HPLC and LCMS/MS analyses confirmed the presence or absence of aflatoxins in selected toxigenic and atoxigenic isolates. qPCR analysis revealed aflP, aflS, aflR and aflO transcripts as the most upregulated genes across the tested isolates whereas false detection of aflD gene transcript was observed in both induced and uninduced A. flavus isolates. Diversity Index (H) analyses ranged from 0.11 (Nandi samples) to 0.32 (Kisumu samples). Heterokaryon compatibility ranged from 33 % (for the Makueni samples, n = 3) to 67 % (Nandi samples, n = 6). The KDV1 maize line was more sensitive to A. flavus infection in comparison to GAF4. We also tested the biocontrol of atoxigenic isolates to inhibit toxin production by aflatoxigenic strains on infected maize kernels. It was shown that the atoxigenic strain (KSMO12) could inhibit the aflatoxigenic strain (KSM014) depending on the atoxigenic concentration during infection. To our knowledge, this is the first reported study for A. flavus genetic diversity, variation and distribution in Nandi, Homa Bay and Kisumu regions in comparison to and could assist researchers in the selection of biocontrol strategies to mitigate aflatoxin contamination, especially in Makueni and neighbouring regions.
27

Suzuki reactions in novel liquids

Hassanzadeh, Nazanin January 2021 (has links)
Non-ionic deep eutectic solvent (ni-DES) possesses various advantages such as good solvation, biodegradability, and non-toxicity which makes it a perfect and environmentally friendly solvent for organic synthesis. A Pd (OAc)2 catalyzed, Suzuki reaction of aryl bromide and N-heteroaryl halide with arylboronic acid in green and novel solvent (ni-DES) is described. In this work, the possibility of using ni-DES and the impact of this solvent on the scope of the reaction is studied. It is illustrated that using the mixture of N-alkyl derivatives of urea and acetamide as a green solvent for Suzuki reaction is achievable even though the desired amount of product was not obtained. However, the high yield in ni-DES can be obtained by choosing 4-bromobenzotrifluoride or 4-bromoanisole as the aryl bromide with arylboronic acid that possess the electron donating groups. Despite that, for getting more yield through Suzuki reaction in ni-DES more studies on optimization are required.
28

Skolbibliotek och fritidshem : Skolbibliotekariers syn på samarbete mellan skolbibliotek och fritidshem / School Library and Afterschool Recreational Center : School librarians view on collaboration between the School Library and the Afterschool Recreational Center

Dahlin Lundberg, Catarina January 2018 (has links)
The purpose of this study is to look into what qualifications required necessary to a collaboration between the school library and the afterschool recreational center. The research questions are: 1) What is the position regarding school librarians to collaboration between the school library and the afterschool recreational center? 2) What qualifications are required of school librarians, according to themselves, in order to collaborate with recreational teachers? 3) How can school librarians view on collaboration and need of competence relate to the Afterscool Recreational Center with the support of the TLC- model? The method used is qualitative research interviews with six school librarians. The interviews took place at their place of work. The theoretical framework for the study have been Montiell-Overalls Theory on collaboration between school librarians and teachers, TLC. The outcome of the interviews shows that in collaboration and competences, as requested in research issues, is of importance of how the principal and school management organizes the work at the schools and it plays a major role in the ability to collaborate. It also shows that school librarians are positive of collaboration but the school's organization is one reason why it is difficult to find time to collaborate. The outcome also shows that the activities of the school library are important for collaboration. Connections between the School Library and the Afterschool Recreational Center lies in the difference and the similarities between them. The qualifications school librarians believe they have can also be used during recreational time. Their functions in their pedagogical work are meant to operate enriching for the students’ progress growth.  Further research within the area is to look into what priorities the school management think is the school libraries assignment towards the after school recreational center and what result the students will get with that pedagogical method that TLC is.
29

Eficacia de los derechos laborales establecidos en el Tratado de Libre Comercio entre Perú y Estados Unidos

Azerrad Urrutia, Cecilia 23 September 2011 (has links)
Desde que el comercio alcanzó cierto grado de envergadura global, fue concebida la idea de establecer una organización global de comercio. Las reuniones entre Estados para la formación de dicho organismo plantearon, entre otras cosas, la necesidad de ligar el comercio internacional con los derechos de los trabajadores. En ese sentido, durante la negociación del Acuerdo General de Tarifas y Comercio (por sus siglas en inglés GATT) y la Organización Internacional de Comercio (OIC), los Estados discutieron sobre la importancia de no utilizar condiciones de trabajo injustas, a fin de crear una ventaja comparativa en el mercado internacional
30

Conversão enzimática de triacilgliceróis em mono e diacilgliceróis de interesse industrial / Enzymatic conversion of triacylglycerols to mono and diacilglycerols of industrial interest

Sylvio Jorge Hares Junior 27 October 2017 (has links)
Mono e diacilgliceróis são produtos empregados na indústria alimentícia, farmacêutica, cosmética e química como emulsificantes e melhoradores de viscosidade de produtos alimentícios, cosméticos e farmacêuticos. No entanto, a forma mais usual de obtê-los é por síntese química, o que acaba rendendo produtos finais caros e com atributos de qualidade, rendimento e de aplicabilidade tecnológica inferiores aos esperados. A busca por formas de obtenção mais racionais, eficientes e com melhor padrão de qualidade destes produtos foi o objetivo principal do trabalho, por meio de hidrólise parcial enzimática, que necessita de condições de reação mais brandas. Foram avaliadas a hidrólise enzimática descontína, empregando como substrato a trioleína técnica, e a hidrólise enzimática descontínua-alimentada, usando como substrato o óleo de girassol médio oléico. Foi utilizada, em ambos processsos, a lipase imobilizada sn-1,3 específica Lipozyme RM IM (de Rhizomucor miehei). A caracterização dos padrões e dos substrados, bem como o acompanhamento da formação dos produtos da hidrólise enzimática foram feitos por determinação da porcentagem de hidrólise, cromatografia em camada delgada (TLC), dos perfis das curvas de fusão e cristalização por calorimetria diferencial de varredura (DSC), cromatografia gasosa (CG) e cromatografia de exclusão de tamanho de alto desempenho (HPSEC). Os parâmetros de hidrólise descontínua foram o tempo de reação, a temperatura e a concentração inicial de substrato. Os parâmetros de hidrólise descontínua-alimentada foram tempo de enchimento e intervalo de alimentação de substrato. Para as respostas analíticas de porcentagem de hidrólise e de composição de frações lipídicas foi aplicado um modelo de regressão múltipla com base em metodologia de superfície de resposta. Os resultados experimentais observados nas reações de hidrólise enzimática descontínua de trioleína técnica mostraram de 24,7 a 34,2% de mono e diacilgliceróis (para 5% de óleo na emulsão) e de 21,4 a 33,6% de mono e diacilgliceróis (para 20% de óleo na emulsão). Os resultados experimentais observados nas reações de hidrólise enzimática descontínua-alimentada de óleo de girassol médio oléico (para 15% de óleo na emulsão), mostraram de 7,9 a 31,8% de mono e diacilgliceróis. Os modelos de superfície de resposta foram considerados significativos e preditivos. As hidrólises obtidas no formato descontínuo e descontínuo-alimentado permitiram efetivamente a obtenção de frações de mono/ diacilgliceróis com vários graus de eficiência de conversão e com corretas identificação e quantificação das frações de lipídios procuradas. As correlações feitas entre porcentagem de hidrólise e entalpias de cristalização e fusão, corroboradas com os resultados qualitativos e/ou quantitativos diretos obtidos na cromatografia de camada delgada (TLC) e de HPSEC, demonstraram que estes atributos podem positivamente indicar a ocorrência efetiva de reação de hidrólise, além de auferir uma escala de desempenho de reação alinhada com o previsto na literatura, à medida que são aumentadas a temperatura, o tempo de hidrólise e a porcentagem inicial de substrato oleoso, sob regime descontínuo, e que puderam ser melhoradas, de forma inovadora, sob parâmetros de tempo total de alimentação e de intervalo de alimentação, sob regime descontínuo-alimentado. A hidrólise parcial enzimática de triacilgliceróis utilizando lipase imobilizada sn-1,3 específica pode ser considerada uma alternativa às vias químicas para a produção de misturas de mono e diacilgliceróis para utilização como aditivos químicos. / Mono and diacylglycerols are products used in the food, pharmaceutical, cosmetic and chemical industries as emulsifiers and viscosity improvers for food products, cosmetics and pharmaceuticals. However, the most usual forms of obtaining them are by chemical synthesis, which ends up yielding expensive final products with attributes of quality, yield and technological applicability lower than expected. The search for more rational, efficient and better quality standards of these products was the aim of the work, through partial enzymatic hydrolysis, which requires milder reaction conditions. Discontinuous enzymatic hydrolysis was evaluated using technical triolein as substrate and discontinuous-fed enzymatic hydrolysis using as the substrate the mid oleic sunflower oil. In both processes, immobilized lipase sn-1,3 specific Lipozyme RM IM (from Rhizomucor miehei) was used. The characterization of the patterns and substrates, as well as the monitoring of the formation of the products from the enzymatic hydrolysis were made by determining the percentage of hydrolysis, thin layer chromatography (TLC), profiles of the melting and crystallization curves by differential scanning calorimetry ( DSC), gas chromatography (GC) and high performance size exclusion chromatography (HPSEC). The parameters of discontinuous hydrolysis were the reaction time, the temperature and the initial substrate concentration. The parameters of discontinuous-fed hydrolysis were filling time and substrate feed interval. For the analytical responses of hydrolysis percentage and composition of lipid fractions a multiple regression model was applied based on response surface methodology. The experimental results observed in the reactions of discontinuous enzymatic hydrolysis of technical triolein indicated amounts of mono- and diacylglycerols from 24.7 to 34.2% (for 5% of oil in the emulsion) and from 21.4 to 33.6% for mono and diacylglycerols with 20% oil in the emulsion. The experimental results observed in the reactions of discontinuous-fed enzymatic hydrolysis of mid oleic sunflower oil (for 15% oil in the emulsion), showed from 7.9 to 31.8% of mono and diacylglycerols. Response surface models were considered significant and viii predictive. The hydrolysis obtained in the discontinuous and discontinuous-fed form allowed to obtain fractions of mono / diacylglycerols with various degrees of conversion efficiency and with correct identification and quantification of the lipid fractions sought. The correlations between the percentage of hydrolysis and enthalpies of crystallization and fusion, corroborated with the qualitative and / or quantitative direct results obtained in thin layer chromatography (TLC) and HPSEC, showed that these attributes can positively indicate the effective occurrence of reaction of Hydrolysis, in addition to achieving a reaction performance scale in line with the literature, as the temperature rate, the hydrolysis time and the initial percentage of oily substrate are increased under a discontinuous regime and can be improved, in a innovative form, under parameters of total filling time and feeding interval, under a fed-batch regime. The partial enzymatic hydrolysis of triacylglycerols using specific sn-1,3-specific immobilized lipase may be considered an alternative to the chemical pathways for the production of mono- and diacylglycerol blends for use as chemical additives.

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