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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

Avaliação em laboratorio de repelentes para proteção pessoal utilizando-se o mosquito Aedes 9S.) albopictus (SKUSE) como modelo

Bueno, Virginia de Souza 29 June 1999 (has links)
Orientador: Carlos Fernando Salgueirosa de Andrade / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-07-25T07:57:05Z (GMT). No. of bitstreams: 1 Bueno_VirginiadeSouza_M.pdf: 4533141 bytes, checksum: cea7025bba129bc7b8d816914f129a53 (MD5) Previous issue date: 1999 / Resumo: Repelentes de insetos tem sido utilizados como uma alternativa, dentro das modernas técnicas de manejo integrado de vetores e insetos incômodos, na prevenção da picadas de insetos hematófagos e, portanto, de doenças por eles veiculadas. nicialmente, o presente trabalho faz uma comparação de metodologjas utilizadas em laboratório para avaliação de produtos potencialmente repelentes. Foram utilizados ratos "baby", dedos de mãos humanas e o mosquito Aedes albopictus como modelos. De acordo com os resultados obtidos, a utilização de dedos humanos mostrou-se mais adequada na avaliação de repelentes para uso humano. Uma vez escolhida a metodologja, foram realizados três estudos. Repelentes químicos comercializados regularmente no Brasil, em sua maioria mostraram-se eficazes. Dos aparelhos eletrônicos testados nenhum deles mostrou eficiência como repelente, confirmando estudos realizados em outros países e com outras espécies de mosquitos. Os ensaios com óleos essenciais provenientes de plantas com potencial repelente, apresentaram resultados satisfatórios e abrem caminho para que outros estudos sejam realizados. Além do óleo de citronela (Cymbopogon nardus S.), já comercializado, novos estudos devem dar ênfase aos óleos de poejo (Mentha pulegium L.) e de alecrim (Rosmarinus officinalis L.) / Abstract: Insect repellents have been used as an alternative method among modem techniques for vectors and nuisance insects integrated management in order to prevent hematophagous insect bites and, consequently the diseases carried by them. he present study initially compares some laboratory methodologies to evaluate potentially repellent products. Baby rats, human fingers and the mosquito Aedes albopictus were used as models. According to the obtained results, the utilization of human fingers have shown to be more suitable in the evaluation of repellents for human use. After the methodology was chosen three researches were carried out. Most chemical repellents regulary commercialized in Brazil proved to be effective. None of the electronic devices tested proved to be effective repellent thus confirming other studies carried out in other countries with other species of mosquitoes. he experiments with essential oils from plants with repellent potentiality have shown satisfactory results and lead the way for other researches to be done. Besides the oil from citronella (Cymbopogon nardus S.), already in the market, emphases must be done on the oils from pennyroyal (Mentha pulegium L.) and rosemary (Rosmarinus officinalis L.) / Mestrado / Parasitologia / Mestre em Ciências Biológicas
22

Comparative Analysis of the Gut Microbiome in Wild and Lab Strains of Anopheles Quadrimaculatus Say, and its Effect on Innate Immunity

Moen, Eleanor Marie 10 August 2018 (has links)
Vector competence of mosquitoes has been linked to the conditions in which the larvae mature to adults. The microbial community obtained from the rearing environment is suspected to be one key factor in this interplay. A better understanding of how the rearing environment affects the gut microbiome and Anopheles-Plasmodium interactions could be useful for understanding observed lab vs. field differences in Plasmodium biology and help drive future control efforts. Currently there is a lack of research done on the differences between lab strain mosquitoes and their rearing environments and how lab mosquitoes differ from wild type mosquitoes. Bridging this gap and studying how rearing habitats change gut microbiomes is critical for optimizing the lab-rearing environment. This thesis focuses on the effects larval rearing has on microbiome establishment and innate immune responses in the common malaria mosquito, Anopheles quadrimaculatus.
23

The chaetotaxy of the second and third instar larvae of Aeoes abserratus (F. & Y.) with particular reference to instar differentiation (Diptera: Culicidae).

MacKenzie, Duncan West 01 January 1966 (has links) (PDF)
No description available.
24

The Role of Rhomboid proteases and a Oocyst Capsule protein in Malaria Pathogenesis and Parasite Development

Srinivasan, Prakash 11 June 2007 (has links)
No description available.
25

Battle of the Viruses: Aripo Virus Induced Superinfection Exclusion of Mosquito-borne Viruses

Carver, James A. 06 January 2021 (has links)
Flaviviruses are a single-stranded, positive sense, RNA virus that affect around 400 million people annually. Flaviviruses are transmitted by arthropod vectors, the most common vector being the mosquito. Currently, many mosquito control strategies are in use, these control strategies are diverse in both efficiency and cost. However, developing new vector control strategies is becoming increasingly important, due to climate changing affecting vector population distribution and the current limitations conventional control strategies face. Although many different control strategies exist, there is limited research pertaining to reducing viral infection in the vector. Reducing the transmission capabilities of vectors could help relieve the disease burden felt around the world. Aripo virus (ARPV), an insect-specific flavivirus, has ushered in opportunities to discover a novel approach to arbovirus control. The exclusionary effects of ARPV were explored as a means to eventually understanding superinfection exclusion (SIE) and utilizing it as a calculated defense against mosquito-borne disease. Aripo virus was evaluated for its SIE potential in vitro and experiments were performed to explore the possible mechanisms underlying SIE. Aripo virus showed significant exclusion against the flaviviruses tested, as well as an alphavirus. Additionally, West Nile virus was unable to adapt and overcome SIE barriers over 9 serial passages. Lastly, ARPV was superinfected with chimeric viruses to asses replication kinetics, and possible exclusionary bias was seen with non-structural genes. These data show ARPV is capable of reducing viral titer, as well as possible leads into understanding the underlying mechanism of SIE, a critical step in utilizing SIE as a strategy to combat vector-borne disease. / Master of Science in Life Sciences / Mosquitoes all around the globe spread disease causing pathogens. Infection with viral pathogens such as West Nile virus, Zika virus, and Japanese encephalitis virus can cause lifelong health effects or even death. Risk for increased spread of mosquito-vectored disease is on the rise. The continued effects of climate change, increasing temperatures away from the equator, and increased encroachment into natural areas for urban development, is opening the door for new infectious diseases spread by mosquitoes. There are many ways to curb the effects that these viral diseases can have on humans, including vaccines or mosquito repellents, and even eliminating mosquito populations is helping to reduce the effects of these important diseases. Sadly, no one method can solve the problem. The methods of dealing with mosquito transmitted disease are likely to be most effective when done in combination. The more countermeasures that attempt to stop the spread of disease, the greater dent in reducing the spread of disease. In this dissertation, we dive into the realm of stopping disease transmission before humans become a factor. If we can limit mosquito infections, then the disease has no way of reaching humans. An approach to controlling mosquito infections could lie within viruses themselves. Aripo virus, an insect-specific virus, is interesting in that it does not affect vertebrates, only mosquitoes. When Aripo virus infects mosquito cells at the same time as deadly viruses, the deadly viruses do not accumulate in the mosquito cells nearly as much. Within mosquito cells, Aripo virus was able to reduce the levels of West Nile virus, St. Louis encephalitis virus, Japanese encephalitis virus, Zika virus, and Mayaro virus. If the underlying concept of the method of Aripo virus induced exclusion of deadly viruses could be further understood, it could be used to reduce the spread of mosquito-related viral diseases.
26

Mosquito habitats and predation efficiency on mosquito populations in Ginninderra Wetland, Canberra, Australia

Hoa, Vu Minh, n/a January 1993 (has links)
The ecology of mosquito populations in relation to weather conditions, emergent plants and predation in an urban wetland of Canberra was studied. Anopheles annulipes, Aedes notoscriptus, Aedes australicus, Aedes alboannulata, Culex annulirostris and Culex quinquefasciatus were found. Temperature was a major climatic factor in determining the abundance of mosquito populations in the wetland. First collections and subsequent development of mosquitoes in Ginninderra wetland are likely to depend on local weather conditions each year. The wetland proper was not a suitable habitat for mosquito breeding. Tall emergent vegetation may have obstructed oviposition and predation was also important in limiting colonization by mosquitoes. Instead, isolated temporary waterbodies which were free of predators, such as ground depressions, tyre tracks, domestic waste containers, were the most important habitats for mosquitoes adjacent to the Ginninderra wetland. Field experiments found that predation of mosquito larvae by mosquitofish Gambusia qffinis and notonectids Anisops was more efficient in sunlight than shade and this was affected by the height of emergent plants.
27

Avaliação de repelentes eletronicos e estudos quanto a eficiencia de transposição de telas, utilizando Aedes aegypti (Linnaeus, 1762) e Aedes albopictus (Skuse, 1854) (Diptera: Culicidade)

Cabrini, Isaías, 1978- 16 November 2005 (has links)
Orientador: Carlos Fernando Salgueirosa de Andrade / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-05T10:07:55Z (GMT). No. of bitstreams: 1 Cabrini_Isaias_M.pdf: 1094913 bytes, checksum: 29b708cf734298b93b1507f9c318b1ed (MD5) Previous issue date: 2005 / Resumo: Já é bem conhecida há várias décadas a transmissão de diversas doenças para o homem e outros animais, por fêmeas de mosquitos (Diptera: Culicidae). Devido a isso, inúmeros estudos laboratoriais, utilizando sistemas fechados, têm sido realizados para se conhecer melhor o comportamento dos mosquitos. Esses sistemas consistem em olfatômetros, túneis de vento, câmaras-teste, entre outros, e podem ser utilizados para avaliar, por exemplo, produtos para a proteção pessoal, como os repelentes e telas de proteção, obtendo-se dados sobre a eficácia em impedir que as fêmeas de mosquitos consigam picar um hospedeiro. O presente trabalho teve como objetivo desenvolver inicialmente um sistema de câmara-teste, a partir de um sistema já descrito em literatura científica, para estudos com mosquitos Aedes spp. O sistema foi feito em isopor, sendo composto de uma caixa grande conectada a um tubo, que por sua vez foi dividido em duas seções. Ao todo, o sistema ficou então constituído por três seções. Na parte distal do tubo foram liberadas fêmeas de Aedes aegypti ou Ae. albopictus que eram atraídas para os estímulos de uma mão humana e uma fonte de luz, disposta na caixa, na outra extremidade. Primeiro foi avaliado nessa câmara-teste a repetitividade do padrão de comportamento de atração, verificando-se que proporção dos mosquitos seria atraída para a outra extremidade. / Abstract: The transmission of some diseases to humans and others animals by mosquitoes (Diptera: Culicidae) is knew. Due to this fact many studies have been done in the laboratory in order to better understand the mosquito behavior. Examples of some studies are those with olfactometers, wind tunnels and test-chambers, among others. Such approaches can also be in order to evaluate products for personal protection such as repellents and bednets, gathering data on their efficacy in avoiding female bites. The aim of the present work was to develop a test-chamber based on a system already described to study Aedes spp. mosquitoes. The system was constructed with polystyrene, consisting of a cage connected to a tube, which was divided in three sections. At the distal end of the tube Aedes aegypti or Ae. albopictus females were released, to be attracted to the stimulus of a human hand and a light source placed at the box in the opposite side. This system was developed in order to assess the host behavior testing a attraction of the stimulus for females, evidenced by their attraction to the other end of the tube. The developed test-chamber proved to be feasible to be use, since 94% Ae. albopictus and 95% of Ae. aegypti females were attracted to the section where the attractive were placed. Sonic frequencies devices, the so-called electronic repellents for insects, spiders and rats have been sold for many years. / Mestrado / Mestre em Parasitologia
28

Perceptions of measures to control Aedes mosquitoes and mosquito-borne diseases in Costa Rica

Bandzuh, John Thomas IV 06 July 2016 (has links)
Aedes mosquitoes are responsible for the transmission of several arboviruses throughout tropical and subtropical regions of the world. In the Americas, Aedes aegypti is the most competent vector of dengue, chikungunya, Zika, and yellow fever. With up to 400 million cases globally each year, dengue fever is the fastest growing vector-borne disease in the world, and it has become an increasingly significant risk to global health. In the Western Hemisphere, dengue, and more recently chikungunya and Zika, exists throughout much of Latin America and the Caribbean. Both diseases are spread via Aedes mosquitoes and both constitute major health risks in Costa Rica. A dengue outbreak in Costa Rica in 2013 was the largest epidemic in the country since the return of the disease in 1993. Moreover, between 2014 and 2015 there was a 54.9% increase in dengue cases in Costa Rica, further demonstrating the relevancy of research on mosquito-borne diseases. Given this context, this study employs qualitative methods to critically investigate measures to combat Aedes mosquito-borne diseases in Costa Rica. Data were collected using household interviews (n = 80); semi-structured key informant interviews with public health officials, researchers, nonprofit organizations, and community leaders (n = 22); and a focus group discussion in each of two study areas. The results provide broad and place-specific information about mosquito control efforts and other actions deployed in Costa Rica to mitigate mosquito-borne diseases. The data reveal differences in perceptions and disease incidence among household interviewees as well as where households source information about mosquitoes and mosquito-borne diseases. Varying degrees of knowledge on mosquitoes and mosquito-borne diseases were uncovered across the study sites, as were differing attitudes among the general population regarding mosquito control techniques (e.g., fumigation, education campaigns, and household visits by public health officials). Additionally, data indicated a gap in knowledge regarding the ability of the public to report mosquito-related problems to health authorities. Households also exhibited discrepancies in knowledge pertaining to chikungunya transmission and details about the vector. / Master of Science
29

Molecular characterisation of esterases implicated in £organophosphate resistance in Culex quinquefasciatus mosquitoes

Merryweather, A. T. January 1988 (has links)
No description available.
30

Control of disease due to perennially transmitted malaria in children of rural Sierra Leone

Marbiah, Nuahn Tomanh January 1996 (has links)
No description available.

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