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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.
1

Crescimento e aspectos reprodutivos do pimelodus maculatus triploides

Bertolini, Rafaela Manchin January 2018 (has links)
Orientador: George Shigueki Yasui / Resumo: A triploidização é uma ferramenta interessante para produzir peixes estéreis. No Mandi amarelo, Pimelodus maculatus isso pode ser aplicada como uma ferramenta de reconstituição de espécies ameaçadas através de transplante de células germinativastronco. No capítulo I, objetivou-se estabelecer um protocolo eficiente para a triploidização da espécie P. maculatus empregando choques de térmicos. As temperaturas testadas foram de 37°C, 38°C e 39°C, 2 minutos pós-fertilização durante 2 minutos. Os embriões intactos serviram como grupo controle diplóide. A ploidia foi confirmada por citometria de fluxo, diâmetro nuclear dos eritrócitos e citogenética. Taxas de fertilização e sobrevivência foram verificadas nos principais estágios de desenvolvimento embrionário (clivagem, blástula, gástrula, segmentação e eclosão), assim como a porcentagem de larvas normais e anormais, e eficiência da triploidização. O choque térmico reduziu significativamente a sobrevivência no estágio de gástrula (P = 0,0178), somito (P = 0,0469) e incrementou o porcentual de larvas anormais (P = 0,0261). A menor sobrevivência foi observada para o tratamento a 39°C. Todos os tratamentos apresentaram altas porcentagens de indivíduos triploides, sendo o maior valor observado para o choque a 38°C (96,7%). Com base nos resultados acima, foi obtido um eficiente protocolo de triploidização em P. maculatus utilizado choque quente (38°C, 2 mpf e duração de 2 minutos). No capitulo II, foram avaliados aspectos relacionados ao... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Triploidization is an interesting tool to produce sterile fish. In the spotted catfish Pimelodus maculatus, this may be used as a tool for reconstitution of endangered species based on stem germ cell transplantation. In Chapter I, the study aimed to establish an efficient protocol for triploidization in the spotted catfish P. maculatus using temperature shock. The temperatures tested were 37°C, 38°C e 39°C, 2 min postfertilization during 2 minutes. Intact embryos served as diploid control. Ploidy status was confirmed by flow cytometry, nuclear diameter of erythrocytes and karyotyping. Fertilization and hatching rates were verified at the main embryo stages (cleavage, blastula, gastrula, somite stage and hatching), the percentage of normal and abnormal larvae and also the efficacy of triploidization. Heat shock decrease the survival at blastula stage (P= 0,0178), somite (P = 0,0469) and increased the percentage of abnormal larvae (P = 0,0261). The lowest survival was observed at 39 °C. All treatments presented high percentages of triploid individuals, and the highest values were observed for heat shock at 38°C (96,7%). Based on results above, it was obtained an efficient protocol for triploidization in P. maculatus using heat shock (38°C, 2 min postfertilization during 2 minutes). In Chapter II, aspects related to the growth and reproductive performance of diploid (2n) and triploid (3n) of P. maculatus were evaluated. The objective was to evaluate growth according with the plo... (Complete abstract click electronic access below) / Mestre
2

Bangladesh’s forest NGOscape : visions of Mandi indigeneity, competing eco-imaginaries, and faltering entrepreneurs in the climate of suspicion

Dodson, Alex Ray 23 September 2013 (has links)
The assemblage of competing development programs I call an "NGOscape", effective in Bangladesh's forest spaces, is a window into understanding both local and extra-local imaginings of the future of these spaces. By tracing the close interaction of three of the most prominent forces in operation in Bangladesh's forest NGOscapes: indigeneity, environmentalism, and entrepreneurialism, I discuss how the government and NGOs (Non-Governmental Organizations) work to increase management and securitization of these forces. Through ethnography and close analysis of the minority Mandi community, and NGOs in the capital city of Dhaka and in rural Modhupur, Tangail, I interpret Modhupur as a vital and telling site for examining the close interdependence of these three themes. Adivasi ("aboriginal") folklorization and representation is deployed by Mandi leaders and NGOs, and provides a space for Mandi internal debates about authenticity, representation, modernity, and the way forward. Neoliberal imaginings centered on transforming Mandi livelihoods into something more appropriately modern are realized on the ground, evidenced by Alternative Income Generation (AIG) programs that push for market integration, and attempt to utilize claims about adivasi indigeneity to advance a security-management paradigm, national stability, and civic responsibility. Young activists and environmentalists based in Dhaka are crucial forces in promoting the broader development and NGO agenda, utilizing the themes of environmental responsibility and progressive conservation programs. Additionally, development agendas are complicated by other factors, such as eco-tourism trends that seek to indoctrinate the Mandi and other rural actors into acceptable and responsible ways of managing environment, while also relying on national pride. These competing forces rely on national pride and social shaming to transform rural Bangladeshis from being somehow "backward" into more desirable, modern subjects. Yet severe distrust within a larger "climate of suspicion," between adivasi leaders, activists, and the state ultimately disrupt the fluidity of development practices at the local level. The result places various actors in precarious positions, left to interpret and be interpreted into development, NGO, and state-based objectives. / text
3

Desenvolvimento ontogenético larval e variabilidade populacional de Pimelodus britskii em um reservatório neotropical / Dontogenetic evelopment and variability population Pimelodus britskii in neotropical reservoir

Almeida, Mara Cristina [UNESP] 31 May 2016 (has links)
Submitted by MARA CRISTINA DE ALMEIDA almeida (mara_macrisal@hotmail.com) on 2016-08-18T17:37:02Z No. of bitstreams: 1 TESE QUE VAI PARA BANCA final.pdf: 2216514 bytes, checksum: d47cfdeade85054b179e9c11c4c16e5b (MD5) / Rejected by Ana Paula Grisoto (grisotoana@reitoria.unesp.br), reason: Solicitamos que realize uma nova submissão seguindo a orientação abaixo: O arquivo submetido está sem a ficha catalográfica. O arquivo submetido não contém a folha de aprovação. A versão submetida por você é considerada a versão final da dissertação/tese, portanto não poderá ocorrer qualquer alteração em seu conteúdo após a aprovação. Corrija esta informação e realize uma nova submissão contendo o arquivo correto. Agradecemos a compreensão. on 2016-08-19T19:26:20Z (GMT) / Submitted by MARA CRISTINA DE ALMEIDA almeida (mara_macrisal@hotmail.com) on 2016-08-22T17:53:06Z No. of bitstreams: 1 VERSÃO FINAL BANCA COM TUDO.pdf: 2412812 bytes, checksum: 49625b8a1c633e2577e04d37766a03b8 (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-08-22T20:43:42Z (GMT) No. of bitstreams: 1 almeida_mc_dr_jabo.pdf: 2412812 bytes, checksum: 49625b8a1c633e2577e04d37766a03b8 (MD5) / Made available in DSpace on 2016-08-22T20:43:42Z (GMT). No. of bitstreams: 1 almeida_mc_dr_jabo.pdf: 2412812 bytes, checksum: 49625b8a1c633e2577e04d37766a03b8 (MD5) Previous issue date: 2016-05-31 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Pimelodus britskii, uma espécie endêmica da bacia do rio Iguaçu, apresenta poucos estudos que envolvam desenvolvimento ontogenético e parâmetros populacionais, deste modo, trabalhos que envolvam esses caracteres são de suma importância, para tomada de medidas de uso e conservação da espécie. Neste trabalho abordamos, no primeiro artigo, o desenvolvimento larval, proporções corporais e subsídios para diferenciar a larva nas fases iniciais de desenvolvimento das suas congenéricas. No segundo artigo avaliamos as modificações, ao longo do espaço e do tempo, com relação à abundância, proporção sexual, tamanho de primeira maturação, comprimento médio, relação peso/comprimento, e atividade reprodutiva. Em relação às larvas, inicialmente a pigmentação era escassa e intensificou-se com o desenvolvimento. O comprimento padrão variou de 2,6 a 13,11mm e os miômeros de 34-50. A espécie apresentou alometria negativa do comprimento da cabeça, altura do corpo, distância pré-dorsal e distância pré-anal em relação ao comprimento padrão e altura da cabeça, comprimento do focinho e diâmetro do olho em relação a comprimento da cabeça, e as estruturas corporais em todas as fases larvais de desenvolvimento são cartilaginosas. Foram capturados na totalidade 9.204 indivíduos, em quatros locais diferentes de coletas em 9 (nove) etapas. Evidenciou que a população de P.britskii, por diferentes etapas e locais, apresentou diferença significativa em seus parâmetros populacionais. A maior abundância (CPUE) ocorreu na etapa I e na estação de coleta Cavernoso (Cav). O comprimento médio da população variaram 15,5±6,2 cm, sendo os indivíduos maiores capturados na Etapa III e na estação de coleta Iate Clube Candói (Iat). O crescimento foi alométrico negativo, como o melhor fator de condição (K), encontrado na etapa III e na estação Iat, como ocorreu também para o comprimento médio. O índice de atividade reprodutiva (IAR), na escala temporal foram mais intenso na etapa I e no espaço na estação Cav. E em relação a diferentes estações de coleta, foram mais intenso nas estações quente (verão) e praticamente nulo na estações mais frias (outono). Considerando estes resultados podemos inferir que a população apresenta tendência à estabilização. / Pimelodus britskii, an endemic species of Iguaçu River basin, has scarce studies involving ontogenetic development and population parameters. So studies involving these characters are of great importance to take protection e conservation measures. This study presents, in the first paper, body proportions and subsidies to differ larval initial developing phases larval of its congenerics. The second paper evaluated changes, over space and time, related to abundancy , sexual proportion, first maturation size, medium lengh , weight /size relation and productive activity. The larvae initially pigmentation was scarce and intensified with the development, the standard length ranged from 2.6 to 13.11mm and myomeres from 34-50. The findings showed negative head length allometry, body height, predorsal length and pre-anal distance from the standard length and head height, snout length and diameter of the eye in relation to head length and structures in all larval stages of development are cartilaginous. 9.204 individuals were captured in nine years in four different collection places. It showed that the population of P.britskii, through different stages and places significant difference in their population parameters. The highest abundance (CPUE), occurred in stage I and Cavernous collection station (Cav). The average length of the population ranged 15.5 ± 6.2 cm, with the largest individuals caught in Stage III and gathering station Candói Yacht Club (Iat). The allometric growth was negative as the best condition factor (K) found in step III and Iat station as also observed for the mean length. The reproductive activity index (IAR), the temporal scale were more intense in stage I and space in Cav station. And in relation to different collection stations were more intense in the warm seasons (summer) and virtually nil in colder seasons (autumn). Considering these results we can conclude that the population has a tendency to stabilize.
4

Inductive weld of joints for optical fiber pipe

Usman, Muhammad January 2017 (has links)
The current study presents an induction heating system design for fiber optics pipes joints. Remote heating methods are probably inconvenient due to non-uniform heat distribution resulting in unreliable joints. The induction heating generates uniform heat distribution which can be achieved by proper designing of inductive heating coil, and power system inverter that drives the induction system. Two different shaped open jaw type heating coils were designed i.e open claw type coil (OCTC) and curved spiral rectangular coil (CSRC). The coils were designed in COMSOL simulation software to check the coil and workpiece behaviours. These coil designs were then wounded by hand and resistance and inductance of each coil were measured. The OCTC is a short loop coil, having small inductance while the CSRC has a long loop so its inductance is high. CSRC design was selected in the current application. The CSRC inductance was calculated through modified Wheeler formula and current sheet approximation. To design the power inverter, firstly the power density of heating material i.e workpiece was calculated. Then the thermal losses of the coil were calculated, these losses were due to skin effect and proximity effect; and switch losses due to drain to source resistance(RDS) of Mosfets were estimated. The Mazzilli inverter was proposed for power system inverter design which works as a parallel resonant circuit. It was designed in Mandi simulation software and then implemented on hardware. Theoretical results were compared with the practical measurements through Matlab software. Coil efficiency, power inverter efficiency and overall system efficiency were also calculated. This induction heating method for fiber optics joints is repeatable, consistent, generates uniform heat and is more convenient for site-specific heat generated on workpiece. It is portable, user friendly and environmental friendly as well.
5

Efeitos de reservatórios em cascata sobre a biologia reprodutiva de um piscívoro neotropical / Effects of cascade of reservoir on the reproductive biology of a neotropical piscivorous

Silva, Pedro Rogério Leandro da 25 October 2010 (has links)
Made available in DSpace on 2017-07-10T18:13:26Z (GMT). No. of bitstreams: 1 Pedro Rogerio Leandro da Silva.pdf: 3755816 bytes, checksum: 44fdfa816725b798ac0cdf0505598395 (MD5) Previous issue date: 2010-10-25 / Information about the events of life cycle of fish species are the most used for management measures, thus, this study seeks to determine under what conditions Pimelodus britskii is reproducing in the reservoir cascade of the Iguaçu river. Thus, the hypothesis being tested here is: the reproductive biology of this species is not influenced by the sequential of reservoirs? Data were collected between 2004 and 2008 (sampled quarterly) in five sequential reservoirs of the Iguaçu river (Foz do Areia, Segredo, Salto Santiago, Salto Osorio and Salto Caxias) through in the environmental studies of companies Tractebel Energia through the project Ichthyological studies and water quality monitoring of Salto Santiago and Salto Osório reservoirs - Iguaçu river/PR (Salto Santiago, Salto Osorio) and Companhia Paranaense de Energia through the project Biological Analysis of fishes (Foz do Areia, Segredo and Caxias). Samples were collected with gillnets and trammel nets (witches) that were exposed for 24 hours in three strata (margin, surface and bottom). To indentify significant differences between the reservoirs, the mean and median values of catch per unit effort (CPUE), sex ratio (χ²), gonad condition (ΔK), gonadosomatic relationship (RGS) and index of reproductive activity (IRA) were tested by main effect variance analysis, being controlled the temporal variability through blocks. The results of CPUE showed higher catch in Salto Santiago and Caxias reservoirs (23.5 and 21.2 individuals 1.000m²*net*day-¹, respectively), without significant difference between the reservoirs. General sex ratio showed no significant difference (χ²=1.70; 1:1), but significant differences were recorded between Segredo and Salto Santiago reservoirs. The length-weight relationship fitted the model Wc=0.0043LS3, 2106 (R2=0.9813) indicating that the values of ΔK increases with growth (allometric positive). The average values for gonad condition factor suggested greater weight/length relationship for the individuals of Salto Osorio (0.000251) and lower at Caxias (0.00005), indicating a significant difference between Caxias and the other reservoirs, except Segredo. The RGS for female in reproduction showed no significant difference between the reservoirs. The IRA was classified as incipient to intense between Foz do Areia (3.97) and Salto Osorio (11.02), indicating differences between the medians, however, showed no reservoirs which differ among themselves. Thus, the reproductive biology of P. britskii along the gradient of the cascade is not being affected due to environmental conditions of the Salto Santiago reservoir, however, after this place the results indicate trend of influence. / As informações sobre os eventos do ciclo de vida das espécies de peixes são as mais utilizadas para as medidas de manejo, deste modo, este trabalho pretende determinar em que condições Pimelodus britskii está se reproduzindo na sequência de reservatórios do rio Iguaçu. Assim, a hipótese a ser testada aqui é: a biologia reprodutiva dessa espécie não está sendo influenciada pelos reservatórios sequenciais? Os dados analisados foram obtidos entre 2004 e 2008 (coletas trimestrais), em cinco reservatórios sequenciais do rio Iguaçu (Foz do Areia, Segredo, Salto Santiago, Salto Osório e Salto Caxias), nos estudos ambientais das empresas Tractebel Energia através do Projeto Estudos ictiológicos e monitoramento da qualidade da água dos reservatórios de Salto Santiago e Salto Osório - rio Iguaçu/PR (Salto Santiago e Salto Osório) e Companhia Paranaense de Energia, através do projeto Análise biológica de peixes (Foz do Areia, Segredo e Caxias). As amostragens foram realizadas com redes de espera simples e tresmalho (feiticeiras), que ficaram expostas por 24 horas em três estratos (margem, superfície e fundo). Para identificar as diferenças significativas entre os reservatórios, os valores médios e medianos da captura por unidade de esforço (CPUE), proporção sexual (χ²), fator de condição gonadal (ΔK), relação gonadossomática (RGS) e índice de atividade reprodutiva (IAR), foram testados através da análise de variância de efeitos principais, sendo controlada a variabilidade temporal por meio de blocos. Os resultados da CPUE mostraram maior captura nos reservatórios de Caxias e Salto Santiago (23,5 e 21,2 indivíduos*1.000m² de rede*dia-¹, respectivamente), não apresentando diferença significativa entre os reservatórios. Considerando a proporção sexual geral, não houve diferença significativa (χ²=1,70; 1:1), porém diferença significativa foi registrada entre os reservatórios de Segredo e Salto Santiago. A relação peso-comprimento ajustada assumiu o modelo Wc=0,0043Ls3,2106 (R2=0,9813) indicando que os valores de ΔK aumentam com o crescimento (alométrico positivo). Os valores médios para o fator de condição gonadal sugeriram maior relação peso/comprimento dos indivíduos de Salto Osório (0,000251) e menores em Caxias (0,00005), apontando diferença significativa entre Caxias e os demais reservatórios, exceto Segredo. A RGS para as fêmeas em reprodução indicou que não houve diferença significativa entre os reservatórios. O IAR foi classificado de incipiente a intenso entre Foz do Areia (3,97) e Salto Osório (11,02), indicando diferença significativa entre as medianas, no entanto, não apresentou quais reservatórios diferiram entre si. Assim, a biologia reprodutiva de P. britskii ao longo do gradiente da cascata não está sendo influenciada devido às condições ambientais do reservatório de Salto Santiago, entretanto, após esse reservatório os resultados apontam tendência de influência.

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