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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.
61

Foraging Behavior and Reproductive Success of the Malaria Mosquito Anopheles gambiae s.s. (Diptera: Culicidae)

Stone, Christopher M. 26 September 2011 (has links)
No description available.
62

New tools for the study of virus-vector interactions in mosquitoes

Wiley, Michael R. 06 March 2012 (has links)
Mosquito-borne diseases continue to be a burden to global health. The viruses that cause these diseases are maintained in nature through a biological transmission cycle involving susceptible vertebrate and mosquito hosts. While knowledge of the interactions occurring between mosquito-borne viruses and vertebrates is considerable, much less is known about the interactions of these viruses with their disease vectors. Studies with Drosophila melanogaster have been important in understanding how insects respond to viral infections. However, mosquitoes and the viruses they vector have co-evolved during a long period of time. Unfortunately, many of the genetic advantages of a fly model are not available when working with mosquitoes. Nevertheless, a sequenced genome, and molecular tools such as high-throughput sequencing and RNAi knockdown are helping to bridge these gaps. Here we describe several additional tools for the study of virus-vector interactions in the mosquito. / Ph. D.
63

La Crosse virus and Dirofilaria immitis: Abundance of Potential Vectors in Southwestern Virginia and the Effects of Dual Infection on Aedes albopictus and Ochlerotatus triseriatus

Grim, Devin Christine 24 January 2007 (has links)
Microfilarial enhancement of viral transmission is well documented, however only one previously studied model used components that occur together in nature and therefore has realistic implications. La Crosse (LAC) virus encephalitis is the most common mosquito-borne illness affecting children in the United States. LAC virus is prevalent in the Great Lake and Mid-Atlantic states and coincidently this area overlaps the region of highest infection for Dirofilaria immitis, the nematode that cause canine heartworm disease. Ae. albopictus and Oc. triseriatus are important vectors of La Crosse virus and among the numerous species able to transmit D. immitis. In this study, Aedes albopictus and Ochlerotatus triseriatus were infected with La Crosse virus and Dirofilaria immitis to determine the effects of dual infection on the dissemination and transmission of the virus. The effects of dual infection varied between the species tested. Ae. albopictus had significantly higher tolerance to D. immitis infection than Oc. triseriatus. Dissemination for dually infected Ae. albopictus were higher than the control group for all days tested, except one. Transmission rates for D. immitis infected Ae. albopictus were significantly higher than the control group on day 14 post infection. No microfilarial enhancement of viral dissemination or transmission was observed for Oc. triseriatus. The infection, dissemination, and tranmission rates were low for both species compared to rates of previous studies. Low rates could be a result of low susceptibility for the strains tested. In a second study, mosquitoes were collected from two counties in Southwestern Virginia to determine the abundance of potential La Crosse virus and D. immitis vector species. The abundance and distribution of mosquito species were examined in 2003 and 2004 using gravid traps. An unexpected finding was the significant increase in the abundance of Ochlerotatus japonicus. In 2003, collections were made over 192 trap nights from June to August yielding 5,879 mosquitoes of which only 24 were Oc. japonicus. In 2004, 12,151 mosquitoes were trapped from June to September over 160 trap nights. Oc. japonicus was the second most abundant mosquito species and the dominant Ochlerotatus species collected in gravid traps. Oc. japonicus was collected in low numbers in June, but the abundance increased significantly in July and remained consistent throughout the rest of the season. Of the other major mosquito species collected in this study, only Aedes albopictus exhibited a similar seasonal pattern as Oc. japonicus. Other biological similarities of Oc. japonicus and Ae. albopictus are discussed. / Master of Science in Life Sciences
64

Morphological differentiation of eggs and comparative efficacy of oviposition and gravid traps for Aedes vectors at different habitats

Bova, Jacob Edward 03 July 2014 (has links)
Mosquito surveillance is an integral part of understanding mosquito-borne disease, including and not limited to the La Crosse virus. The primary container-inhabiting Aedeni vectors include Aedes triseritatus, Aedes albopictus, and Aedes japonicus. To better understand the efficacy of gravid traps and oviposition traps as surveillance methods for these mosquitoes, field studies were conducted in three different habitat types. Ae. triseriatus, Ae. albopictus, Ae. japonicus, and Aedes aegypti eggs were described with the aid of color images and SEM. All eggs were broadly cigar shaped with Ae. triseriatus and Ae. japonicus eggs being dull or matte black while Ae. albopictus and Ae. aegypti eggs were shiny jet black. Ae. triseriatus eggs were larger, lighter in color, and have a rougher appearance when compared to Ae. japonicus. Ae. albopictus and Ae. aegypti can be differentiated by the distinct presence of a micropylar collars in Ae. aegypti. Ovitrap and gravid trap efficacy for the surveillance of Ae. triseriatus, Ae. albopictus, and Ae. japonicus were measured in three different habitats on two different sites. Both sites contained the same 2ha habitats with varying degrees of forest canopy disturbance. Ae. triseriatus was the most abundant mosquito on all sites. Ovitraps and gravid traps were efficient in collecting Ae. triseriatus, while ovitraps were not efficient in collecting Ae. japonicus and Ae. albopictus. / Master of Science in Life Sciences
65

Ecological profiling of bird-mosquito interactions in Central Virginia

Riggan, Anna 18 July 2011 (has links)
Current methods of mosquito surveillance estimate general population abundances, but fail to represent the relationship of vector abundance to host density important to determining transmission risk of mosquito-borne pathogens (MBP). We sought to address this limitation by creating a novel mosquito trap that directly sampled mosquitoes seeking to feed on nesting birds. The primary objectives of this study were to (1) assess the efficiency of the Nest Mosquito Trap (NMT) and how this is affected by nest box size. (2) assess whether the NMT affects bird, specifically nest success in Prothonotary Warblers (Protonotaria citrea), and adult behavior. (3) compare our novel trap to existing methods. (4) profile the ecological parameters associated with bird/ mosquito interactions. Our results allow us to conclude that the NMT is not only an effective means of capturing host-seeking mosquitoes and measuring mosquito/ bird interactions, but does not have a deleterious effect on avian nesting success.
66

Identificação, diversidade e sazonalidade de maruins (diptera:ceratopogonidae) em diferentes ambientes do município de Luíz Alves, SC :uma abordagem preliminar para o controle /

Veber, Marcos Pedro, 1985-, Vitorino, Marcelo Diniz, 1968-, Universidade Regional de Blumenau. Programa de Pós-Graduação em Engenharia Ambiental. January 2010 (has links) (PDF)
Orientador: Marcelo Diniz Vitorino. / Dissertação (Mestrado em Engenharia Ambiental) - Programa de Pós-Graduação em Engenharia Ambiental, Centro de Ciências Tecnológicas.
67

Eficácia de três tipos de armadilhas para captura de culicídeos em área de Mata Atlântica no sudeste do Brasil / Efficacy of three mosquitoes traps in area of Atlantic Forest in the southeastern of Brazil

Chaves, Leonardo Suveges Moreira 06 September 2012 (has links)
Introdução: Armadilhas entomológicas são ferramentas importantes nas atividades de vigilância e controle. Poucos estudos foram realizados para avaliar a eficácia de armadilhas contendo Lurex3 como ferramenta na pesquisa entomológica de culicídeos no Vale do Ribeira. Objetivo: Comparar a eficácia das armadilhas, CDC luminosa, CDC com CO2 mais lurex® e Mosquito Magnet® (MM) Independence com lurex® para a captura de culicídeos. Métodos: foram definidos três pontos próximos da mata, onde foram instaladas as armadilhas, sempre às 15:00 hs e removidas às 21:00 hs com revezamento diário, por três dias consecutivos ao mês, por um ano. Resultados: A armadilha CDC-luz capturou o menor número de mosquitos (1.368), seguida da CDC+CO2+lurex (2.284) e da MM (5.477). O teste de Tukey mostrou diferença significativa, indicando a armadilha MM superior, quando comparada com a CDC-luminosa (p < 0,01) e CDC-CO2-lurex (p < 0,03). Não houve diferença significante entre o total de mosquitos coletados na CDC-luminosa e na CDC-CO2- lurex. O número de espécies capturadas na armadilha MM (63 espécies) foi maior do que na CDC-luminosa (p < 0,001) e CDC-CO2-lurex (p < 0,03). Houve uma associação positiva (OR > 1) para as espécies Ae. scapularis, An. bellator, An. cruzii e Ps. ferox quando utilizada a MM e a CDC-CO2-lurex, não houve associação (OR = 1) para a espécie Ae. serratus e Cx. nigripalpus . Conclusões: O poder de captura da MM mostrou ser significativamente maior em comparação às outras duas. A associação entre as espécies antropofílicas, com interesse epidemiológico, foi maior com a MM / Traps are important appliance in entomological surveillance and control activities. Few studies have been conducted to evaluate the efficacy of traps containing Lurex3 in entomological research of mosquitoes in the Ribeira Valley. Objective: Compare the efficacy of traps, CDC light, CO2 plus lurex with CDC and Mosquito Magnet ® (MM) Independence with lurex ® to capture mosquitoes. Methods: defined three points near the forest, where the traps were installed, always at 15:00 pm and removed at 21:00 pm to relay daily for three consecutive days a month in one year. Jaccard and Sorensen indices indicated similarity between traps. To assess diversity employed Renyi profiles. Statistical analyses applied were: ANOVA with Fishers exact test, Tukey test and p value; Chi-square association test and linear regression. Results: The CDC light traps captured the lowest number of mosquitoes (1368), followed by the CDC + CO2 + lurex (2284) and the MM (5477). The Tukey test showed significant differences, indicating the trap MM superior when compared with CDC-light (p <0.01) and CDC-lurex-CO2 (p <0.03). There was no statistically significant difference between the total number of mosquitoes collected in CDC light-and CO2-CDC-lurex. The number of species caught in the trap MM (63 species) was higher than the CDC-light (p <0.001) and CDC-lurex-CO2 (p <0.03). There was a positive association (OR> 1) for the species Ae. scapularis, Anopheles bellator, Anopheles cruzii and Ps. ferox when using the CDC and MM-CO2-lurex, no association (OR = 1) for the species Ae. serratus and Cx nigripalpus. Conclusions: The efficacy of capture of MM was significantly higher compared to the other two. The association between anthropophilic species with epidemiological interest was higher in MM
68

Atividade dos fungos entomopatogênicos Tolypocladium cylindrosporum, Lecanicillium psalliotae e Conidiobolus macrosporus isolados de mosquitos no Centro-Oeste do Brasil em Aedes aegypti / Activity of the entomopathogenic fungi Tolypocladium cylindrosporum, Lecanicillium psalliotae and Conidiobolus macrosporus isolated from mosquitoes in the Midwest of Brazil in Aedes aegypti

Silva, Juliano Juscelino 01 June 2017 (has links)
Submitted by Erika Demachki (erikademachki@gmail.com) on 2017-07-17T16:47:39Z No. of bitstreams: 2 Dissertação - Juliano Juscelino Silva - 2017.pdf: 1989710 bytes, checksum: f45b210b1488868b181e806fa7091267 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-07-18T11:01:03Z (GMT) No. of bitstreams: 2 Dissertação - Juliano Juscelino Silva - 2017.pdf: 1989710 bytes, checksum: f45b210b1488868b181e806fa7091267 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-07-18T11:01:03Z (GMT). No. of bitstreams: 2 Dissertação - Juliano Juscelino Silva - 2017.pdf: 1989710 bytes, checksum: f45b210b1488868b181e806fa7091267 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-06-01 / Microorganisms are agents of biological control, among them, the entomopathogenic fungi stand out. Tolypocladium cylindrosporum IP419 and IP425, Lecanicillium psalliotae IP456, IP491 and IP492 were isolated from sentinel larvae. Conidiobolus macrosporus IP396 and L. psalliotae IP455 isolated from adult culicíneos. At 5 and 15 days, depending on the fungus, conidia were scraped from sporulated culture plates and adjusted in suspensions. In 30 eggs/ replicate, 50 μL of suspension of the isolates IP419, IP425, IP455, IP456, IP491 and IP492 were applied in five concentrations (3.3 × 103 to 3.3 × 105 conidia/cm2). For IP 396, 2.5 × 104 conidia/cm2 was applied. In experiments with larvae (10 L3/repeat), five concentrations were applied (3.3 × 105 to 3.3 × 107 conidia/ml) for IP419, IP425, IP455, IP456, IP491 and IP492, and (103 to 105 conidia/ ml) for IP396. The controls were treated with distilled water. Adults were exposed to five concentrations (3.3 × 104 to 3.3 × 106 conidia/cm2) of conidia of IP419 and IP425. For IP396 and IP455, IP456, IP491 and IP492, adults were exposed to the sporulated culture. Adult controls were not exposed to fungi. Ten adults were exposed in 4 replicates. There was no significant activity of the isolates tested against eggs. Mortality of larvae treated with T. cylindrosporum was ≤ 90% at the lowest concentration (3.3 × 105 conidia/ml) and 100% at the highest concentration (3.3 × 107 conidia/ml). The LC50 and LC90 were 3.5 × 104 conidia/ml and 6.8 × 106 conidia/ml for IP419 and 5.9 × 105 and 1.3 × 107 conidia/ml for IP425. The TL50 and TL90 for IP419 at the highest concentration (3 × 107 conidia/ml) was ≤ 7 hours. The concentrations applied had a significant effect (P <0.001). In larvae treated with IP396, mortality of L3 increased with conidia concentration, in the highest concentration (105 conidia /ml), was ≤ 57% in 48 h. There was no growth of the fungus on L3 exposed in agar medium for IP396, for T. cylindrosporum the fungal development was ≤ 70%. Mortality of larvae in controls was ≤ 15%. L. psalliotae had no larvicidal activity. Mortality of adults treated with T. cylindrosporum was ≤ 75%. There was fungal development on corpses ≤ 65%, the concentrations applied had a significant effect (P <0.001). The cumulative mortality of IP396 treated adults reached 100% after 5 days, and ≥ 80% over 10 days for L. psalliotae. The results show that T. cylindrosporum and C. macrosporus have potential for integrated control of larvae and adults of A. aegypti. / Microrganismos são agentes de controle biológico, dentre eles, destacam-se os fungos entomopatogênicos. Tolypocladium cylindrosporum IP419 e IP425, Lecanicillium psalliotae IP456, IP491 e IP492 foram isolados de larvas sentinela. Conidiobolus macrosporus IP396 e L. psalliotae IP455 isolados de culicíneos adultos. Em 5 e 15 dias, dependendo do fungo, conídios foram raspados de placas com cultura esporulada e ajustados em suspensões. Em ovos (30 ovos/repetição), foram aplicados 50 μL de suspensão dos isolados IP419, IP425, IP455, IP456, IP491 e IP492 em cinco concentrações (3,3 × 103 a 3,3 × 105 conídios/cm2). Para IP396, aplicou-se 2,5 × 104 conídios/cm2. Em testes com larvas (10 L3/repetição), cinco concentrações foram aplicadas (3,3 × 105 a 3,3 × 107 conídios/ml) para IP419, IP425, IP455, IP456, IP491 e IP492, e (103 a 105 conídios/ml) para IP396. Os controles foram tratados com água destilada. Adultos foram expostos a cinco concentrações (3,3 × 104 a 3,3 × 106 conídios/cm2) de conídios de IP419 e IP425. Para IP396 e IP455, IP456, IP491 e IP492, adultos foram expostos à cultura esporulada. Adultos controle não foram expostos aos fungos. Foram expostos 10 adultos, em 4 repetições. Não houve atividade significante dos isolados testados contra ovos. A mortalidade de larvas tratadas com T. cylindrosporum, foi ≤ 90% na menor concentração (3,3 × 105 conídios/ml) e 100% na maior concentração (3,3 × 107 conídios/ml). A CL50 e CL90 foi de 3.5 × 104 conídios/ml e 6.8 × 106 conídios/ml para IP419 e de 5.9 × 105 e 1.3 × 107 conídios/ml para IP425. O TL50 e TL90 para IP419, na maior concentração (3 × 107 conídios/ml) foi ≤ 7 horas. As concentrações aplicadas tiveram efeito significativo (P < 0,001). Em larvas tratadas com IP396, a mortalidade de L3 aumentou com a concentração de conídios, na maior concentração (105 conídios/ml), foi ≤ 57% em 48 h. Não houve crescimento do fungo sobre L3 expostas em meio ágar para IP396, para T. cylindrosporum o desenvolvimento fúngico foi ≤ 70%. A mortalidade de larvas nos controles foi ≤ 15%. L. psalliotae não teve atividade larvicida. A mortalidade de adultos tratados com T. cylindrosporum foi ≤ 75%. Houve desenvolvimento fúngico sobre cadáveres ≤ 65%, as concentrações aplicadas tiveram efeito significativo (P < 0,001). A mortalidade acumulada de adultos tratados com IP396 chegou a 100% após 5 dias, e ≥ 80% em dez dias para L. psalliotae. Os resultados mostram que T. cylindrosporum e C. macrosporus têm potencial para controle integrado de larvas e adultos de A. aegypti.
69

Efeito da predação de copépodos ciclopóides (Copepoda: Cyclopidae) sobre o tamanho do corpo, razão sexual e comportamento de ovoposição de Aedes albopictus (Diptera: Culicidae)

Cardôso, Helton Charllys Batista 25 July 2012 (has links)
Made available in DSpace on 2015-04-17T14:55:25Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 1509338 bytes, checksum: e0a2529155ec99b45b55b847965af181 (MD5) Previous issue date: 2012-07-25 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Cyclopoid copepods have been used as biological agents in successful programs to control mosquito larvae, but the impacts of this predation on adult mosquito populations are still poorly understood. The present study compared the sex ratios and body sizes (measure as wing length) of Aedes albopictus mosquitoes emerging from recipients containing the copepod predator Mesocyclops ogunnus with control situations without this predator. We found that copepod predation significantly biased mosquito sex ratios towards females, and that both the males and females emerging from copepod-containing recipients were significantly larger than control insects. The ecological and epidemiological consequences of the changes induced by copepod predation on mosquito populations are discussed. / Copépodos ciclopóides têm sido utilizados como agentes de controle biológicos em programas de controle de larvas de mosquito, mas os impactos dessa predação sobre as populações de mosquitos adultos ainda são pouco compreendidos. O presente estudo comparou as razões sexuais e o tamanho do corpo de mosquitos Aedes albopictus (com base no comprimento da asa) que emergiram de recipientes contendo o copépodo predador Mesocyclops ogunnus com aqueles que emergiram de recipientes controles. Com base nos resultados obtidos constatou-se que a predação de copépodos alterou significativamente a razão sexual de mosquitos favorecendo fêmeas. Machos e fêmeas que emergiram de recipientes contendo copépodo foram significativamente maiores em comparação aqueles que emergiram do controle. As alterações induzidas pela predação de copépodos em populações de mosquitos apresentam importâncias ecológicas e epidemiológicas, visto serem as fêmeas de mosquitos do gênero Aedes os principais vetores do dengue .
70

Estudo da filogenia dos anofelinos brasileiros do subgênero Nyssorhynchus e padronização da amplificação dos genes do receptor do peptídeo sexual (SPR) e do peptídeo sexual (SP)

Oda, Letícia Tiemi Egami [UNESP] 21 February 2014 (has links) (PDF)
Made available in DSpace on 2014-11-10T11:09:42Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-02-21Bitstream added on 2014-11-10T11:58:42Z : No. of bitstreams: 1 000786519.pdf: 3462716 bytes, checksum: 103148a0254d8605a0efee8e6685ef8c (MD5) / A evolução da hematofagia em mosquitos é sem dúvida a adaptação mais importante desse grupo de inseto em termos dos patógenos transmitidos pelos vetores, causadores de diversas doenças importantes no mundo de hoje. Um equívoco comum que os mosquitos como um grupo são conhecidos taxonomicamente foi gerado, mas há muitas espécies para serem descobertas e classificadas. Os mosquitos da família Culicidae que possui como subfamília Anophelinae, formam um grupo diversificado, de origem monofilética, com distribuição global. Vale assinalar que apenas uma minoria das 3.200 espécies conhecidas atualmente são importantes vetores de patógenos para os seres humanos. Além de seu papel na transmissão de patógenos, os mosquitos têm muito a oferecer à ciência básica, por exemplo, como indicadores da biodiversidade, do grau de degradação do meio ambiente natural, das diversas formas de uso do solo e para estudos de evolução e de especiação. Os mosquitos possuem um peptídeo chamado Peptídeo Sexual que é expresso nas glândulas acessórias dos machos e inseminado nas fêmeas durante a cópula. A ligação deste peptídeo ao seu receptor encontrado nas fêmeas, desencadeia uma vasta resposta comportamental no inseto, que inclui a mudança de hábito alimentar, dando preferência a alimentos protéicos, a recusa de cópula com outros machos, a indução da oviposição dentre outras. Este projeto teve como objetivo o estudo deste peptídeo e seu respectivo receptor em diferentes anofelinos brasileiros visando gerar dados a respeito da filogenia e da caracterização de um possível marcador genético. Foram feitas extrações de DNA dos mosquitos, reações de PCR, sequenciamento, e análise das sequencias para foramação das árvores filogenéticas no programa Phylip pelas analyses de Máxima Verossimilhança, Neighbor-Joining e Parcimônia. As árvores geradas neste projeto foram comparadas com a árvore padrão do artigo de ... / The evolution of mosquitoes hematophagy is undoubtedly the most important adaptation of this group of insect in terms of pathogens transmission, which cause various important diseases in the world nowadays. Thus, a common misconception that mosquitoes as a group are known taxonomically was generated, but there are many species to be discovered and classified. The mosquitoes of Culicidae Family which has Anophelinae as subfamily are a diverse group of monophyletic origin, with global distribution. It is noteworth that only a minority of the 3200 species known today, are important vectors of pathogens to humans. Besides the pathogens transmission, mosquitoes have much to offer to basic science, for example, as biodiversity indicators, indicating also the degradation degree of the natural environment, the various ways soil is explored and for studies of evolution and speciation. The mosquitoes have a peptide called Sex Peptide which is expressed in accessory glands of males and is inseminated in females during copulation. The binding of this peptide to its receptor triggers a major behavioral response in the insects, which includes changes in eating habits, giving preference to protein, the refusal of mating with other males, induction of oviposition, among others. This project aims the study of this peptide and its corresponding receptor in different brasilian anophelines in order to generate data about phylogeny and characterization of a possible genetic marker. DNA extraction were made, PRC reaction, sequencing, and sequence analysis for tree generation in the program Phylip whith the anylisis of Maximum Likelihood,Neighbor- Joining and Parsimony.The generated tree was compared whith a standard tree of Foste et al (2013) which used three diferent genes COI, CAD e white gene. We didn´t get successful whith SPR tree, but, with SP the classification of the tree were almost the same of Foster et al (2013). Another tree was generated whith ...

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