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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.
11

Study of heat-shock-induced cell death in Saccharomyces cerevisiae with a deficiency of YDL100c

Liu, Shih-ming 19 July 2008 (has links)
YDL100cp is the ArsA homologous protein found in Saccharomyces cerevisiae. Previous studies show that deletion of YDL100c was not lethal but unable to grow at 40¢XC. To study the role of YDL100c in response to lethal heat shock, the wild type strain (WT) and YDL100c disrupted strain (KO) were exposed to 50¢XC for 30 min. The growth and survival rate of KO cells at 30¢XC after heat-shock was lower than that of WT cells, and the difference was complementated by introducing the plasmid carrying YDL100c. The oxidative stress has been shown to be involved in the heat-induced cell death in S. cerevisiae. Therefore, the intracellular molecular oxidation level, expression of antioxidant genes, trehalose accumulation, and glutathione (GSH) content were further examined. The intracellular molecular oxidation was increased in KO compared to WT when exposed to 50¢XC, suggesting heat-shock-induced cell death is related to oxidation of intracellular components. The results also demonstrated that both WT and KO had a decreased GSH content and trehalose accumulation after heat-shock, indicating that GSH and trehalose are not directly involved in the slow growth of KO after heat-shock. However, CTT1 expression is decreased in KO compared to WT when exposed to 50¢XC, suggesting that decreased CTT1 expression resulted in the increased intracellular oxidation and YDL100c is likely involved in the activation of CTT1 expression.
12

Caracterização de uma região genômica relacionada a uma anomalia de viveiro em Eucalyptus

Lourenção, Juliana Caroline [UNESP] 30 April 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:26:03Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-04-30Bitstream added on 2014-06-13T20:53:59Z : No. of bitstreams: 1 lourencao_jc_me_botib.pdf: 1696836 bytes, checksum: b5322f2b21a2b979131662a74b2c8aae (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Uma anomalia foi detectada na progênie F1 de um cruzamento controlado entre genitores normais e sem parentesco de Eucalyptus grandis, em um viveiro de mudas para plantios comerciais da empresa Suzano Papel e Celulose. As plantas anormais apresentaram altura reduzida, superbrotamento caulinar, redução drástica da área foliar e alteração na forma do limbo da folha. A proporção entre plantas afetadas e normais foi de 3:1 (3 plantas normais : 1 planta anômala), sugerindo uma segregação mendeliana do caráter, que foi confirmada pelo teste do qui-quadrado (χ 2=2,32; p>0,1). Através da técnica de BSA (Bulked Segregant Analysis) utilizada em conjunto com marcadores RAPD (Random Amplified Polymorphic DNA) foi possível identificar um marcador ligado a essa anomalia de eucalipto, o qual foi convertido em SCAR (Sequence Characterized Amplified Region). A sequência SCAR apresentou identidade a sequências expressas de eucalipto do banco de dados de ESTs (Expressed Sequence Tags) do projeto FORESTs-FAPESP, portanto, encontra-se em uma região do genoma que pode estar envolvida direta ou indiretamente com o caráter da anomalia. Diante do exposto, este trabalho teve como objetivo a caracterização molecular dessa região genômica relacionada à anomalia observada em mudas de eucalipto. Na análise de ligação das marcas, molecular e morfológica, estas apresentaram-se ligadas a uma distância de 0,0 cM com 0% de freqüência de recombinação (LOD= 1000), demonstrando que o marcador molecular está relacionado à anomalia. A sequência SCAR apresentou similaridade a um EST de 632 pb do banco de dados GenBank e a um consenso de 841pb do banco de dados FORESTs-FAPESP, os quais apresentaram o domínio Bet v 1, uma família de proteínas relacionadas à defesa da planta. Como a região em estudo está relacionada a uma família multigênica, esta se apresentou em várias... / From a controlled crossing between two normal genitors without parentage from relationship of a seedling nursery for commercial crops of Suzano Papel e Celulose it was observed a lethal anomaly in Eucalyptus grandis full sib family F1. The abnormal plants had reduced height, lack of apical dominance, drastic reduction in the leaf area and an alteration in leaf blade. Segregation ratio was 3:1 (3 normal plants : 1 anomalous plant). Thus, this anomaly is probably inherited in a mendelian manner (χ2=2,32; p>0,1). By using the BSA (Bulked Segregant Analysis) approach used with RAPD (Random Amplified Polymorphic DNA) markers, it was possible to identify one marker linked to this anomaly, which was later converted to SCAR (Sequence Characterized Amplified Region). The SCAR sequence was similar to ESTs (Expressed Sequence Tag) from FOREST-FAPESP database, hence, it is inside a genome region that is supposed to be directly or indirectly involved in the anomaly character. Based on such pieces of information, the present research had as main objective to carry out the molecular characterization of the genomic region related to the anomaly observed in eucalyptus seedlings. During the linkage analyses of molecular and morphologic markers, the latter presented 0% recombination frequency and a distance of 0 cM with LOD=1000. The SCAR sequence was similar to EST of 632 bp from GenBank and a consensus of 841 bp from FORESTs, which presented the Bet v 1 domain, a protein family related to plant defense. As the analyzed region is related to a multigenic family, it was observed in several copies in the eucalyptus genome, making difficult its cloning. By the analyses carried out both in FORESTs and GenBank, it was noticed that the similarity between SCAR and EST is restricted to SCAR 5’ region. In the 3’race technique it was verified that EST 3’ region... (Complete abstract click electronic access below)
13

Estudo dos efeitos letais e subletais (reprodução e teratogênese) do fármaco triclosan para Daphnia similis, Ceriodaphnia dubia, Ceriodaphnia silvestrii (cladocera, crustacea) / Study of sublethal and lethal effects (reproduction and teratogenisis) of the pharmaceutical compound triclosan to Daphnia similis, Ceriodaphnia dubia, and Ceriodaphnia silvestrii (cladocera, crustacea)

LAMEIRA, VANESSA 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:54:42Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:08:00Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energéticas e Nucleares - IPEN/CNEN-SP
14

Estudo dos efeitos letais e subletais (reprodução e teratogênese) do fármaco triclosan para Daphnia similis, Ceriodaphnia dubia, Ceriodaphnia silvestrii (cladocera, crustacea) / Study of sublethal and lethal effects (reproduction and teratogenisis) of the pharmaceutical compound triclosan to Daphnia similis, Ceriodaphnia dubia, and Ceriodaphnia silvestrii (cladocera, crustacea)

LAMEIRA, VANESSA 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:54:42Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:08:00Z (GMT). No. of bitstreams: 0 / Até pouco tempo, o conhecimento da contaminação dos ecossistemas aquáticos, estava restrito a metais e agrotóxicos, sendo pouca ênfase dada a produtos farmacêuticos, que, apesar de serem encontrados em concentrações de nanogramas a microgramas, podem causar efeitos letais e induzir malformações nos organismos. Estudos ecotoxicológicos têm sido realizados para identificar os efeitos destas substâncias, contudo, os dados são insuficientes, principalmente no que se refere a efeitos subletais e de toxicidade em espécies de ambientes tropicais e subtropicais. Efeitos letais e subletais, como crescimento e reprodução, são determinados através de ensaios ecotoxicológicos agudos e crônicos, sendo as malformações dificilmente evidenciadas por estes ensaios. Diante disto, pesquisadores vêm desenvolvendo metodologias mais refinadas, como por exemplo, a exposição direta de embriões a produtos químicos em ensaios de teratogênese. Para Cladocera estes ensaios são restritos. O objetivo deste trabalho foi estudar os efeitos letais e subletais de um antimicrobiano, Triclosan, através de ensaios de ecotoxicidade com Daphnia similis, Ceriodaphnia. dubia e C. silvestrii. A fim de se estimar com maior rigor os efeitos em ambientes tropicais e subtropicais, os ensaios foram realizados com água natural como água de diluição, com e sem fotoperíodo. Também foram realizados ensaios em água Milli- Q água reconstituída, sem fotoperíodo de modo a observar a toxicidade do produto sem interferentes externos. Estágio do desenvolvimento embrionário de D. similis, C. dubia e C. silvestrii foram identificado de modo a otimizar os ensaios de teratogênese. Para o estudo da toxicidade, foram realizados ensaios de ecotoxicidade aguda com D. similis, C. dubia e C. silvestrii e ensaios crônicos com D.similis e C. silvestrii. Para a classificação dos estágios do desenvolvimento embrionário, ovos foram cultivados in vivo a temperatura de 20°C (D. similis) e 25°C (C. dubia e silvestrii), observados a cada hora, até o desenvolvimento completo do organismo. Posteriormente, as condições dos ensaios de teratogênese foram estabelecidas sendo realizados com D. similis. A CE50 48H de Triclosan para D.similis e C. silvestrii em água natural reconstituída com fotoperíodo foi de 0,23 e 0,10 mg.L-1, respectivamente, e de 0,13 mg.L-1para C. silvestrii, sem fotoperíodo. Para os ensaios com água Milli-Q reconstituída, sem fotoperíodo, os valores de CE50;48H para D. similis, C. dubia e C. silvestrii foram de 0, 22; 0,09 e 0,08 mg.L-1, respectivamente. O CEO para D. similis foi de 0,1 mg.L-1 e a o valor de IC50 relativo às malformações das neonatas nos testes crônicos foi de 0,057 mg.L-1. Para C.silvestrii o CEO foi de 0,04 mg.L-1, não sendo evidenciadas malformações nas neonatas. Sete estágios foram observados no desenvolvimento embrionário dos cladoceros com duração (horas) de 34 (±3) para C. dubia, 36(±2) para C. silvestrii e de 51 (±5) para D. similis. O valor de IC50 para malformação nos ensaios de teratogênese (exposição direta de embriões) para D. similis foi de 0,075 mg.L-1, próximo ao obtido nos ensaios crônicos / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energéticas e Nucleares - IPEN/CNEN-SP
15

Recessive lethal amber suppressors in yeast

Brandriss, Marjorie Carol. January 1975 (has links)
Thesis: Ph. D., Massachusetts Institute of Technology, Department of Biology, 1975 / Vita. / Bibliography: leaves 114-122. / by Marjorie C. Brandriss. / Ph. D. / Ph. D. Massachusetts Institute of Technology, Department of Biology
16

A New Form of Warfare: The rise of non-lethal weapons.

Dando, Malcolm R. January 1996 (has links)
An exploration of deploying non-lethal weapons in todays chaotic post cold-war world; thereby facilitating peacekeeping deployments without casualties. Dando argues a more sinister outcome could be the result.
17

Icke dödande vapen : Försvarsmaktens senaste verktyg i internationella insatser / Non-lethal weapons : The Swedish Armed Forces’ latest tool in international operations

Karlsson, Jens January 2009 (has links)
<p>Due to the increasing international operations for the Swedish Armed Forces these new types of opponents needs new tools to cope with these commitments. A couple of years ago the Swedish Armed Forces had no non-lethal weapons, but today the Swedish soldier has a number of tools to choose from.</p><p>The purpose of this paper is for the reader to get a presentation of which non-lethal weapons are used today by the Swedish Armed Forces and a sample of what non-lethal weapons are out on the market today. My main question is <em>which non-lethal weapons do the Swedish Armed Forces’ miss in their non-lethal capabilities set.</em></p><p>I have collected information from a wide selections of sources like reports from the Swedish Defence Research Agency, the Swedish Armed Forces’ own regulations and the Internet. The information is then processed and divided into five chapters: The development of non-lethal weapons, description of technologies, non-lethal weapons in the Swedish Armed Forces, Non-lethal weapons on the market and Results.</p><p>This paper is limited to handheld, portable and man to man non-lethal weapons, all non-lethal weapons in the Swedish Armed Forces or on the international market are not covered.</p><p>My conclusion is that the Swedish Armed Forces should acquire three 40 mm projectiles, one 12-gauge projectile and one TASER®.</p>
18

Icke dödande vapen : Försvarsmaktens senaste verktyg i internationella insatser / Non-lethal weapons : The Swedish Armed Forces’ latest tool in international operations

Karlsson, Jens January 2009 (has links)
Due to the increasing international operations for the Swedish Armed Forces these new types of opponents needs new tools to cope with these commitments. A couple of years ago the Swedish Armed Forces had no non-lethal weapons, but today the Swedish soldier has a number of tools to choose from. The purpose of this paper is for the reader to get a presentation of which non-lethal weapons are used today by the Swedish Armed Forces and a sample of what non-lethal weapons are out on the market today. My main question is which non-lethal weapons do the Swedish Armed Forces’ miss in their non-lethal capabilities set. I have collected information from a wide selections of sources like reports from the Swedish Defence Research Agency, the Swedish Armed Forces’ own regulations and the Internet. The information is then processed and divided into five chapters: The development of non-lethal weapons, description of technologies, non-lethal weapons in the Swedish Armed Forces, Non-lethal weapons on the market and Results. This paper is limited to handheld, portable and man to man non-lethal weapons, all non-lethal weapons in the Swedish Armed Forces or on the international market are not covered. My conclusion is that the Swedish Armed Forces should acquire three 40 mm projectiles, one 12-gauge projectile and one TASER®.
19

Characterization of Arabidopsis ETHE1, a gene associated with ethylmalonic encephalopathy

Holdorf, Meghan Marie. January 2008 (has links)
Thesis (Ph. D.)--Miami University, Dept. of Chemistry and Biochemistry, 2008. / Title from second page of PDF document. Includes bibliographical references.
20

Complémentation fonctionnelle in vivo des phénotypes observés chez la souris grey-lethal (gl)

Pata, Monica January 2004 (has links)
Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

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