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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.
31

Efeito dos inibidores de proteases benzamidinas nas respostas bioquímico-fisiológicas de Coffea arabica e da cochonilha Coccus viridis / Effect of inhibitors proteases benzamidine in biochemical and physiological responses of Coffea arabica and mealybug Coccus viridis

Lizardo Chávez, Cristian Yizard 19 February 2016 (has links)
Submitted by Nathália Faria da Silva (nathaliafsilva.ufv@gmail.com) on 2017-10-02T12:28:39Z No. of bitstreams: 1 texto completo.pdf: 1361538 bytes, checksum: 2107064ec9fd0a3e1e0676e0c9e8c6d3 (MD5) / Made available in DSpace on 2017-10-02T12:28:39Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1361538 bytes, checksum: 2107064ec9fd0a3e1e0676e0c9e8c6d3 (MD5) Previous issue date: 2016-02-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A cultura do café no Brasil tem muita importância econômica e relevância no setor social, gerando divisas e empregos diretos e indiretos. Por tanto, qualquer fator que diminua a sua produtividade refletirá na economia do país. Uma das possíveis causas da redução de sua produtividade é devido às injurias que os insetos podem causar. Entre estes insetos têm-se Coccus viridis (Green) (Hemiptera: Sternorrhyncha: Coccidae). As plantas ao serem injuriadas são capazes de aumentarem a síntese de inibidores de proteases (IPs) no local da lesão e, também, por toda a sua extensão. Estudos demonstraram que insetos alimentados com plantas previamente pulverizadas com inibidores sintéticos têm seu desenvolvimento prejudicado. Assim, o presente trabalho teve por objetivo avaliar os efeitos dos inibidores de proteases sintéticos, benzamidina e berenil, sobre a atividade proteolítica intestinal de C. viridis e constatar quais foram as alterações na resposta bioquímica em plantas de Coffea arabica. Além disso, avaliar os efeitos destes inibidores nos aspectos biológicos desta praga. Plantas de C. arabica foram infestadas com ninfas de C. viridis e pulverizadas com benzamidina e berenil, em quatro diferentes concentrações: 0; 0,25; 0,5 e 0,75% (p/v). A resposta bioquímica do inseto e do cafeeiro foi realizada após 24 horas da pulverização, coletando-se os insetos e as folhas. A avaliação biológica foi realizada até o aparecimento de novas ninfas de o primeiro instar, sinal de que as cochonilhas chegaram à fase adulta. A atividade das serinoproteases, tripsina-like (amidásica e esterásica) e quimotripsina-like esterásica, foi reduzida devido à presença dos inibidores. O mesmo se obteve em relação à atividade das cisteino-proteases. Nos tratamentos avaliados a atividade de lipoxigenases não apresentou diferença. Entretanto, houve um incremento da produção dos IPs nas plantas com a infestação da cochonilha- verde e na ausência dos inibidores sintéticos. Já nas plantas com o inseto e pulverizadas com os inibidores sintéticos observou-se o contrário, ou seja, uma redução na produção dos IPs. Na avaliação da atividade biológica, os IPs sintéticos usados provocaram diferenças significativas no peso dos insetos, no entanto o comprimento desses insetos não foi afetado. A presença de benzamidina e berenil causou alta taxa de mortalidade, sendo o berenil mais eficiente e não apresentando diferença significativa entre as concentrações. Isto posto, os IPs sintéticos benzamidina e berenil têm potencial uso para controlar a praga cochonilha-verde. / The coffee culture is of an enormous relevance in the Brazil economics and social areas generating many currencies as direct and indirect employees. Such any factor, which decreases its productivity, will directly reflect in country economy. Being insect injuries one of the main causes of lost productivity the scale insect Coccus viridis (Green) (Hemiptera: Sternorrhyncha: Coccidae) is a relevant pest in coffee crops. Plants when attacked increase the synthesis of protease inhibitors (PI ́s) locally or systematically. The use of pulverized synthetic proteases inhibitors prejudice insects’ development. Thus, this work aimed to evaluate the effects of synthetic proteases inhibitors benzamidine and berenil on the gut proteolytic activity of Coccus viridis and to corroborate disrupts in biochemical response of Coffea arabica plants. Furthermore, effects on C. viridis fitness were evaluated. C. Arabica plants were infested with C. Viridis nymphs then benzamidine and berenil were pulverized in concentrations: 0; 0.25; 0.5 e 0.75% (p/v). Evaluations were performed 24 hours after pulverization, insects and leaves were collected for analisys. Biological evaluation was performed until the appearance of young nymphs of the first instar, a sign that the mealybugs reached the adult stage. Serine-proteinases, trypsin-like (amida and ester), ester quimotrypsin-like, and cysteine-proteinases activities, were reduced due to inhibitors presence. There was none differences in plant lipoxygenases between treatments. While there were PI ́s increments in plants infested with C. viridis and absence of synthetic inhibitors. Opposite to plants infested with scale insects and pulverized with synthetic inhibitors in which PI’s production were reduced. Synthetic inhibitors caused significant differences in insect weight; however, the length were not affected. The presence of benzamidine and berenil caused high rates of mortality being berenil more efficient but no matter the concentrations. These results demonstrate the high potential of benzamidine and berenil for use as biological control tools.
32

Sex-linked molecular markers and their application to endocrine disruption research in amphibians

Tamschick, Stephanie 29 November 2016 (has links)
Die weltweit mehr als 7500 Amphibienarten sind durch anthropogene Ursachen wie Habitatzerstörung, Krankheitsverbreitung, Klimawandel und Umweltverschmutzung in ihrem Bestand bedroht. Einige der Ursachen sind kaum erforscht, so die Verschmutzung aquatischer Ökosysteme durch endokrine Disruptoren (EDs), Substanzen, die mit dem Hormonsystem interagieren. Ausgehend von neuen molekularen Markern, welche die Ermittlung des genetischen Geschlechts erstmals bei einigen Hyliden und Bufoniden erlauben, wurde in der vorliegenden Arbeit auf die Wirkung des synthetischen Östrogens 17α- Ethinylestradiol (EE2)und des Weichmachers Bisphenol A (BPA) fokussiert. Für drei Bufonidenarten wurde zunächst die Geschlechtsgebundenheit von Mikrosatelliten getestet und ein XX/XY-System nachgewiesen. Diese und bereits etablierte Marker wurden anschließend in ein neu entwickeltes Versuchsdesign für ED-Studien integriert: Nach gleichzeitiger Aufzucht von Modell- (Xenopus laevis) und Nicht-Modell-Arten (Hyla arborea, Bufo viridis) unter EE2- bzw. BPA- Exposition wurde das genetische Geschlecht bestimmt und mit dem anatomisch und histologisch ermittelten phänotypischen Geschlecht erglichen. Die drei Anuren zeigten starke Empfindlichkeitsunterschiede gegenüber beiden EDs. Umweltrelevante Konzentrationen beeinflussten die somatische Entwicklung und führten zu artspezifischen Gonaden-Fehlbildungen. EE2 bewirkte zahlreiche partielle und komplette Geschlechtsumwandlungen, mit stärkeren Effekten bei X. laevis. Diese Arbeit zeigt somit, dass bereits niedrige EE2- und BPA-Konzentrationen zu starken Schädigungen führen können und die Substanzen aufgrund ihrer erheblichen aquatischen Präsenz als ernstzunehmende Faktoren der Amphibienkrise anzusehen sind. Die Ermittlung des genetischen Geschlechts wird als wichtig eingestuft, um verlässliche Aussagen über ED-Effekte zu treffen. Zudem sollten an der Modell-Art X. laevis gewonnene Erkenntnisse nicht vorbehaltlos auf andere Amphibienarten extrapoliert werden. / The more than 7500 known amphibian species are globally threatened, mainly due to anthropogenic causes like habitat destruction, dispersing diseases, climate change and environmental pollution. Some of the causes are barely investigated, e.g. the pollution of aquatic ecosystems with endocrine disrupting compounds (EDCs), substances that interfere with the hormone system. Based on new molecular markers, for the first time allowing genetic sexing in some hylids and bufonids, this thesis focused on the effects of the synthetic estrogen 7α-ethinylestradiol(EE2) and the plasticizer bisphenol A (BPA). Initially, several microsatellite markers were tested for sex-linkage in three bufonid species, and an XX/XY system could be revealed. Subsequently, these and other established markers were integrated into a newly developed experimental design for EDC-research: after simultaneous exposure of model (Xenopus laevis) and non-model species (Hyla arborea, Bufo viridis) to EE2 or BPA, metamorphs were genetically sexed. Anatomically and histologically determined phenotypic sexes were directly compared with the genetic sex of each individual. The three anurans showed striking differences in their susceptibilities in both EDCexperiments. Environmentally relevant concentrations affected the somatic development and led to species-specific gonadal anomalies. In addition, EE2 provoked high numbers of mixed sex and completely sex-reversed individuals, with more pronounced effects in X. laevis than in the two non-model species. This work shows that low concentrations of EE2 and BPA lead to severe damages. Due to their widespread presence in the aquatic environment, these substances might contribute to the worldwide amphibian crisis. To produce reliable results in EDC-studies, genetic sexing is considered important. Furthermore, findings gained with the model species X. laevis should not unreservedly be extrapolated to other amphibian species.
33

Protonation patterns in reduced and oxidized form of electron transfer proteins / Protonierungsmuster von Elektron-Transfer-Proteinen in reduzierter und oxidierter Form

Dobrev, Plamen 08 May 2012 (has links)
No description available.

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