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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.
161

Avaliação do efeito do R-Limoneno, em concentração subletal, sobre a histologia e histoquímica do intestino médio, e compostos energéticos em larvas de Aedes Aegypti L. (Diptera: Culicidae)

OLIVEIRA, Fernanda Marques de 28 February 2018 (has links)
Submitted by Mario BC (mario@bc.ufrpe.br) on 2018-06-12T14:38:25Z No. of bitstreams: 1 Fernanda Marques de Oliveira.pdf: 1318626 bytes, checksum: 025876d0f4a6762bc9bcd56ee26880a5 (MD5) / Made available in DSpace on 2018-06-12T14:38:25Z (GMT). No. of bitstreams: 1 Fernanda Marques de Oliveira.pdf: 1318626 bytes, checksum: 025876d0f4a6762bc9bcd56ee26880a5 (MD5) Previous issue date: 2018-02-28 / Aedes aegypti is the main transmitter of dengue in 128 countries. Approximately 390 million people are infected and 20,000 of those die each year. The monoterpenes are efficient larvicides against this vector, among them the limonene acts in the midgut of the larvae, interfering in its development. The objective of the research was to evaluate the action of limonene, in sublethal concentration, on histology, histochemistry of midle intestine, and levels of neutral carbohydrates and total proteins in Ae. aegypti larvae. Bioassays of 3rd instar larvae were used. Limonene was used at the LC50 of 27 ppm. The treatments were: limonene and control (water and ethanol), analyzed after 12 and 24 h. The midgut of the larvae treated after 12h presented columnar cells, protuberances and cytoplasmic vacuolization and after 24h there was total disorganization of the epithelium. Histochemically, the treated larvae had higher levels of glycogen when compared to the control group as well as for total protein. Biochemically, there was a significant increase in total protein levels in the treated larvae in relation to the 12 h control and reduction in relation to the 24 h control. There was an increase and reduction in glycogen and total sugar levels in the treated larvae in relation to the controls. It is concluded limonene causes pathological changes in histology and histochemistry in the midgut of the Ae. aegypti larvae, besides interfering in proteins level, glycogen and total sugar. / O Aedes aegypti é o principal transmissor da dengue em 128 países. Aproximadamente 390 milhões de pessoas são infectadas e 20.000 dos afetados morrem ao ano. Os monoterpenos são eficientes larvicidas contra esse vetor, dentre eles o limoneno que atua no intestino médio das larvas, interferindo em seu desenvolvimento. O objetivo da pesquisa foi avaliar a ação do limoneno, em concentração subletal, sobre a histologia, histoquímica do intestino médio, e níveis de carboidratos neutros e proteínas totais em larvas do Ae. aegypti. Foram utilizados bioensaios de larvas 3o ínstar. O limoneno foi usado na CL50 de 27 ppm. Formaram-se os tratamentos: limoneno e controle (água e etanol), analisados após 12 e 24h. O intestino médio das larvas tratadas após 12h apresentou células colunares, protuberâncias e vacuolização citoplasmática e após 24h houve total desorganização do epitélio. Histoquimicamente as larvas tratadas apresentaram níveis superiores de glicogênio quando comparadas ao grupo controle, assim como para proteína total. Bioquimicamente, houve aumento significativo dos níveis de proteína total nas larvas tratadas em relação ao controle 12 h e redução em relação ao controle 24 h. Verificou-se, respectivamente, aumento e redução dos níveis de glicogênio e açúcar total nas larvas tratadas em relação aos controles. Conclui-se que o limoneno provoca alterações na histologia e histoquímica no intestino médio de larvas de Ae. aegypti, além de interferir nos níveis de proteínas, glicogênio e açúcar total.
162

Utilização do sistema de bioflocos na larvicultura de Tilápia-do-Nilo /

Serafini, Raphael de Leão. January 2015 (has links)
Orientador: Maria Célia Portella / Coorientador: Wilson Wasielesky Junior / Banca: Lúcia Helena Sipaúba Tavares / Banca: Rodrigo Schveitzer / Banca: Rosângela Kiyoko Jomori Bonichelli / Banca: Antônio Fernando Monteiro Camargo / Resumo: Com o aumento da demanda mundial de pescado surge uma tendência de intensificação dos sistemas produtivos de criação de organismos aquáticos. Entre os sistemas intensivos de aquicultura, o sistema de bioflocos vem ganhando cada vez mais espaço por ser um sistema relativamente mais simples do que o sistema de recirculação de água e capaz de otimizar a utilização dos recursos hídricos. Apesar do sistema de bioflocos ser atualmente bastante estudado na carcinicultura marinha e na fase engorda de tilápia, a adoção dessa tecnologia na larvicultura de peixes de água doce ainda é um assunto novo e pouco avaliado. O objetivo deste trabalho foi avaliar o efeito de diferentes variáveis de manejo na larvicultura de tilápia-do-nilo neste sistema de criação. Foram realizados quatro experimentos que avaliaram: o tempo de maturação do sistema de bioflocos antes do povoamento das larvas; a utilização de substrato artificial e a adição diária de melaço; a densidade de estocagem das larvas; e diferentes fontes de carbono e relações entre carbono e nitrogênio. Em síntese, o sistema de bioflocos foi eficiente para a produção de juvenis de tilápia em sistemas estático sem a renovação de água, promovendo boa taxa de crescimento e sobrevivência das larvas e melhor aproveitamento da ração (conversão alimentar aparente mais eficiente). A utilização de um inóculo de água contendo bioflocos já estabelecido permite a dispensa de preparo prévio dos tanques de criação anteriormente ao povoamento das larvas, otimizando desta forma as unidades de produção (tanques e viveiros) da piscicultura. A utilização de substratos artificiais não promoveu nenhum beneficio na manutenção dos parâmetros de qualidade de água e no desempenho das larvas criadas no sistema de bioflocos. A adição diária de melaço nos tanques proporcionou melhores... / Abstract: There is a tendency of intensification of aquaculture production systems with the increase in global fish demand. Amongst the intensive aquaculture systems, the biofloc system has been gaining more importance because it is a relatively simple system comparing to the recirculation aquaculture system (RAS), and enables to optimize the use of water resources. The biofloc system is currently widely studied and applied in marine shrimp culture and in tilapia grow out, but the adoption of this technology in larviculture of freshwater fish is still a new subject and scarcely evaluated. The aim of this study was to evaluate different aspects for utilization of this technology during the larviculture of Nile tilapia. Four experiments were performed to evaluate the following issues: time of maturation of the biofloc system before the larvae stocking; use of artificial substrate; daily molasses addition; stocking density; different carbon sources and C/N ratio. In synthesis, the biofloc system was quite efficient for the production of juvenile tilapia in static systems without water exchange, promoting good growth rate and survival of larvae and a better use of the aquafeeds (feed convention ratio more efficient). Using an inoculant containing biofloc water already established dispenses the preparation of tanks prior to larval stocking, optimizing the production units (tanks and ponds) of fish farming. The use of artificial substrates did not promote any benefit in maintenance of the water quality parameters and performance of larvae reared in the biofloc system. The daily molasses addition in tanks improved the larval survival rates. The estimated maximum stocking density that can be used in this low-scale system is up to four larvae per liter. Different organic carbon sources can be used to promote the development of heterotrophic bacteria important for maintenance of this system. Further work should be carried out to assess the use of this ... / Doutor
163

The Roles of DD2R in Drosophila Larval Olfactory Associative Learning

Qi, Cheng January 2019 (has links)
No description available.
164

Studies on the Trematode Larva Neascus

Reyes, Thomas 01 January 1957 (has links) (PDF)
During the spring semesters of 1955 and 1956, while the writer was under the supervision of Dr. A. E. Noble, a preliminary survey was initiated on parasites in local fishes, amphibians, and reptiles occurring in the vicinity of Stockton, California. The collection of specimens in this survey included sixteen green sunfish, Lepomis cyanella, and two bluegills, L. macrochirus. Larval trematodes recovered from the heart and liver of these specimens belonged to the family Diplostomatidae Poirier (1886) which is characterized by a conspicuous constriction separating the fore and hind-bodies. The leaf-like forebody with the lateral borders converging ventrally to form a spoon-like concavity containing the holdfast organ and acetabulum, a hind-body enclosing the reproductive organs, and a bursa copulatrix at the posterior and are diagnostic characteristics.
165

Genetic Dissection of the Drosophila melanogaster Larval Response to Light Measured in Two New Single Larva Assays / Genetic Dissection of the D. melanogaster Larval Response to Light

Busto, Macarena 09 1900 (has links)
In order to initiate a genetic dissection of the Drosophila melanogaster larval response to light, two new single larva assays were designed: the Checker and ON/OFF assays. Each assay allows quantification of different aspects of the larval visual response by permitting the study of discrete behaviours in a single larva. Results of this study indicate that larvae respond to light by modulating their locomotion. In the Checker assay this can be seen as an increase in residence time spent in dark checks. In the ON/OFF assay this can be measured as a decrease in distance travelled during the light pulse, due at least in part to an increase in head swinging. Concomitantly, the larva exhibits a sharp change in direction from its original path when the lights are turned on. When the lights are turned off, the change in direction in the larval path, although smaller than at lights on, is still greater than in the absence of light transitions. Many of the components previously described to function in adult phototransduction and visual system specification, also have roles in the larval photoresponse as mutations in the genes that encode these components, are able to abolish light perception as measured in both the Checker and ON/OFF assays. However, these mutations disrupt only subsets of the behaviours associated with the larval perception of light, thus suggesting the existence of light detecting mechanism independent of the main visual pathway described for the adult visual system. / Thesis / Master of Science (MS)
166

Seeing the light: Combining a behavioural and genetic approach in unraveling the mysteries of the larval visual system of Drosophila melanogaster

Hassan, Jana January 2000 (has links)
Using a behavioural and genetic approach, we employed single-gene mutations and photoreceptor cell ablations to study the molecules and cell-types underlying larval response to light Drosophila larvae modulate their locomotion in response to light In the Checker Assay the response to light is defined as an increased residence time in dark quadrants versus lit. In the ON/OFF Assay, it is in part defined as a decreased path length in the light. Previously, mutations in genes, which function in the adult phototransduction cascade were found to abolish fight perception as defined by a reduction in path length. This response to light was reported to be mediated by rhodopsins, other than Rh1, via a pathway similar to the one present in the adult visual system. After undertaking a similar genetic approach in the Checker Assay, the response to light measured in this assay appears also to be mediated through a similar pathway. Mutations in sine oculis (so), a homeobox gene necessary for proper visual system development, and targeted expression of the cell death gene head involution defective (hid), to larval photoreceptor neurons, abolished light response as measured in the Checker Assay. Thus, mutations affecting development oflarval visual system suggest that this response to light is also housed in the larva’s main photoreceptor organ, the BO. The modular GAL4 system was used to target expression of cell death genes, rpr and hid, to Rh5 and Rh6 expressing larval photoreceptor cells. In strains tested in the ON/OFF Assay, in which Rh5 cells are missing, the response to light is abolished, as measured by both decreased path length and increased head swinging behaviour in the light. In a strain in which Rh6 photoreceptor cells are ablated, this response to light is not abolished. This suggests that Rh5 mediates responses in the ON/OFF Assay, which were previously abolished by mutations in genes operating in the adult phototransduction cascade. Thus Rh5, not Rh6, appears to be necessary in mediating the response to light carried out via a pathway similar to the operating in adult phototransduction. In both ablated strains, Rh5-gal4xUAS-rpr and Rh5-gal4xUAS-hid, the integrity of remaining photoreceptor cells is not compromised, and in the latter strain, the extent of ablation appears to be complete. Previously in the ON/OFF assay, mutations and ablations of cell-types were found to disrupt only a subset of behaviours associated with the larval perception of light. Based upon this evidence it was surmised that Rh1 mediates a basic independent visual system, which operates in the larva. However, uncovering the possible roles in this system was hindered, as parental control strains did not respond. / Thesis / Master of Science (MS)
167

Influencia das caracteristicas do alimento vivo e do regime alimentar na larvicultura de robalo CENTROPOMUS PARALLELUS (Poey, 1860)

Seiffert, Mari Elizabete Bernardini January 1996 (has links)
Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciencias Agrarias, 1996 / Made available in DSpace on 2012-10-16T10:21:49Z (GMT). No. of bitstreams: 0 / Em um primeiro experimento avaliou-se a influência do rotífero Bracionus plicatilis (linhagem "S") e da larva trocófora de mexilhão, como alimento vivo inicial, na sobrevivência de larvas de robalo Centropomus parallelus. No experimento seguinte foram testados rotíferos alimentados com diferentes dietas e avaliada a influência na sobrevivência, crescimento e taxa de insuflação da bexiga gasosa. Larvas obtidas através de indução de desova com HCG, 30 horas após a eclosão foram estocadas (30 peixes/l) em tanques cilindro-cônicos pretos, com volume útil de 36 litros. Após um período de 14 dias de cultivo os experimentos foram encerrados. No experimento I não houve diferenca significativa (a=0,05) entre os tratamentos A (somente rotífero) e B (trocófora e rotífero simultâneos), da mesma forma não houve diferença entre os tratamentos C (trocófora e rotífero altemados com sobreposição) e D (trocófora e rotífero alternados sem sobreposição). Os tratamentos A e B apresentaram sobrevivência superior a C e D. No experimento II não houve diferança significativa entre os tratamentos: A (rotífero com Nannochloropsis oculata), B (rotífero corn 50%N. oculata:50% Saccharomyces cerevisiae) e C (rotífero alimentado com 50%N. oculata:50% S. cerevisiae enriquecido com Selco). A inclusão da trocófora no regime alimentar não melhorou a sobrevivência inicial. Rotíferos alimentados com o regime misto (microalgas e fermento) pareceram atender às exigências nutricionais mínimas das larvas de robalo, ou o Selco não melhorou o valor nutricional do rotífero suficientemente.
168

Efeitos da luz solar e cor do tanque no desenvolvimento larval e produção de pos-larvas do camarão Macrobrachium rozenbergii (De Man, 1879)

Rodrigues, Coralucia Chaltein Bello January 1997 (has links)
Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciencias Agrarias / Made available in DSpace on 2012-10-17T00:33:01Z (GMT). No. of bitstreams: 0 / Com a finalidade de se avaliar o efeito da luz solar e a cor dos tanques no desenvolvimento larval e produção de pós-larvas do Macrobrachium rozenbergii, foi conduzido um experimento junto ao laboratório de camarão de água doce do Departamento de Aqüicultura-UFSC. Tanto a luz solar quanto a cor dos tanques (preto e branco) não influenciaram na captura e ingestão de alimentos pelas larvas. Os tanques de cor preta produziram mais pós-larvas (P<0.05) e em menor período do que os tanques de cor branca, independente da incidência de luz solar. Os tanques pretos com incidência de luz solar indireta, produziram pós-larvas maiores e mais pesadas (P<0.05) do que os tanques pretos que não recebiam a luz solar. Nos cultivos com tanques brancos, a incidência solar não influenciou no peso e comprimento das pós-larvas (P>0.05). Os resultados nos mostram que o tanque de cor preta são mais indicados e que a incidência de luz solar indireta é um fator que influencia positivamente (P<0.05) no peso e no comprimento das pós-larvas recém metamorfoseadas.
169

Estudos moleculares de enzimas do tipo tripsina presentes no intestino médio de larvas de Aedes aegypti / Molecular studies of trypsin-like enzymes present in midgut of Aedes aegypti larvae

Soares, Tatiane Sanches [UNIFESP] 29 July 2009 (has links) (PDF)
Made available in DSpace on 2015-07-22T20:50:11Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-07-29 / O Aedes aegypti é o vetor mais importante de arboviroses humana sendo responsável pelas transmissões de dengue e febre amarela urbana. As enzimas tipo tripsina apresentam um importante papel na digestão de estádios de vida larval e adulto de Ae. aegypti. No presente trabalho, nós identificamos as duas enzimas tipo tripsina majoritárias do intestino médio larval através da construção de uma biblioteca de fragmentos de cDNA de tripsina. Elas são AAEL005607 e AAEL006371, com frequências de expressão de 29,3% e 20%, respectivamente. Análises por PCR semi-quantitativo mostraram que a tripsina AAEL005607 foi transcrita em todos os instars larval, mas a tripsina AAEL006371 apareceu somente nos 3º e 4º instar larvais. A fim de confirmar os dados de transcrição, enzimas tipo tripsina do intestino médio de larvas de 4º instar foram purificadas por cromatografias de afinidade, troca iônica e fase reversa. A tripsina purificada apresentou massa molecular de 28 kDa por SDS-PAGE. Sua sequência de aminoácidos parcial nos permitiu sugerir que a atividade de tripsina é codificada pela sequência AAEL005607. A tripsina purificada (AAEL005607) exibiu um valor de Km de 36,4 μM para o substrato Tosyl-Gly-Pro-Arg-pNa e foi fortemente inibida por AaTI e HiTI, ambos inibidores de tripsina, com valores de Ki de 0,94 pM e 160 pM, respectivamente. Em conclusão, pela primeira vez, a enzima digestiva majoritária de 4º instar larval de Ae. aegypti foi purificada e caracterizada. / Aedes aegypti is the most important vector of human arboviral diseases and it is responsible for dengue and urban yellow fever transmissions. Trypsin-like enzymes plays an important role in the Ae. aegypti adult and larval life stages digestion. In the present work, we identified the two major trypsin-like enzymes of Ae. aegypti larval midgut through the trypsin cDNA fragments library construction. They are AAEL005607 and AAEL006371, with expression frequencies of 29.3% and 20%, respectively. Semi quantitative PCR analysis showed that the AAEL005607 was transcripted in all larval instars, but AAEL006371 appeared only in 3rd and 4th larval instars. In order to confirm the transcription data, trypsin-like enzymes from 4th instar larvae of Ae. aegypti midgut were purified by affinity, ionic exchange and reversedphase chromatographies. Purified trypsin presented molecular mass of 28 kDa by SDS-PAGE. Its partial amino acid sequence allowed us to suggest that the trypsin activity is encoding by AAEL005607 sequence. The purified trypsin (AAEL005607) showed Km value of 36.4 μM for Tosyl-Gly-Pro-Arg-pNa substrate and was strongly inhibited by AaTI and HiTI, both trypsin inhibitors, with Ki of 0.94 pM and 160 pM, respectively. In conclusion, for the first time, the major digestive enzyme of 4th larval instar of Ae. aegypti was identified and characterized. / TEDE / BV UNIFESP: Teses e dissertações
170

Contaminação de solo de áreas de lazer por ovos de Toxocara spp em regiões central e periurbana de Mirante do Paranapanema, São Paulo, Brasil / Soil contamination by Toxocara spp eggs in public areas of parks in central and periurban area of Mirante do Paranapanema, São Paulo, Brasil

Dias, Aparecida Pereira 12 December 2007 (has links)
Made available in DSpace on 2016-01-26T18:55:44Z (GMT). No. of bitstreams: 1 Dissertacao Mestrado Aparecida Pereira Dias.pdf: 334818 bytes, checksum: 8756f98a5299978163e1bfa1237c20bc (MD5) Previous issue date: 2007-12-12 / In order to evaluate the enviromental contamination by Toxocara spp eggs in public areas in Mirante do Paranapanema, São Paulo, Brazil, and to compare the frequencies in central areas (area 1: six parks) and periurban (area 2: seven parks), 250g of soil were collected from five different sites from 13 public parks. Two aliquots of 10 g were analyzed using the centrifuge-fluctuation technique with sodium nitrate (d= 1,200 g/cm3). The contamination was observed in 76.9% of parks, being all the periurban parks contaminated (7/7). On other hand, it wqas registered the presence of Toxocara spp eggs in 50% (3/6) of the central places (p<0.05). From recovered eggs 33.3% were available, and 15.15% had moving larvae. The results pointing the parks of Mirante do Paranapanema as a source of infection for the human population to toxocariasis. / Com o objetivo de avaliar a contaminação ambiental por ovos de Toxocara spp em áreas de lazer de Mirante do Paranapanema, São Paulo, e comparar as freqüências entre as regiões central (área 1: seis praças) e periurbana (área 2: sete praças) do município, foram coletadas amostras de 13 parques/praças públicas. Amostras de 250 gramas de solo foram colhidas de cinco pontos diferentes de cada local, escolhidos aleatoriamente. Foram retiradas de cada amostras, duas alíquotas de 10 gramas. O material foi submetido a lavagens com Tween 80(0,2% v/v) e hidróxido de sódio 0,1N. Para recuperação dos ovos, foi utilizada a solução de nitrato de sódio (d= 1.200 g/cm3), pela técnica de centrífugo-flutuação. Verificou-se que a contaminação ocorreu em 76,9% das praças (10/13), com a ocorrência de ovos em todas as praças da área periurbana (7/7) e em 50% das praças centrais (3/6), com diferença significativa (p<0,05). Dos ovos recuperados, 33,3% apresentaram características de viabilidade, sendo que destes 15,15% estavam larvados. Os resultados mostram que a contaminação destas praças pode oferecer riscos da população humana local para aquisição de toxocaríase.

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