880 resultados para Indo-Iranians.


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The narrow-barred Spanish mackerel (Scomberomorus commerson) is widespread throughout the Indo-West Pacific region. This study describes the reproductive biology of S. commerson along the west coast of Australia, where it is targeted for food consumption and sports fishing. Development of testes occurred at a smaller body size than for ovaries, and more than 90% of males were sexually mature by the minimum legal length of 900 mm TL compared to 50% of females. Females dominated overall catches although sex ratios within daily catches vary considerably and females were rarely caught when spaw n ing. Scomberomorus commerson are seasonally abundant in coastal waters and most of the commercial catch is taken prior to the reproductive season. Spawning occurs between about August and November in the Kimberley region and between October and January in the Pilbara region. No spawning activity was recorded in the more southerly West Coast region, and only in the north Kimberley region were large numbers of fish with spawning gonads collected. Catches dropped to a minimum when spawning began in the Pilbara region, when fish became less abundant in inshore waters and inclement weather conditions limited fishing on still productive offshore reefs. Final maturation and ovulation of oocytes took place within a 24-hour period, and females spawned in the afternoon-evening every three days. A third of these spawning females released batches of eggs on consecutive days. Relationships between length, weight, and batch fecundity are presented.

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Sea cucumbers (Holothuridae and Stichopodidae) have been harvested commercially for at least 1,000 years. The world fisheries for sea cucumbers, however, are not well documented and in general are poorly managed. Depending upon the species exploited, there are two processing procedures for the sea cucumber product. Some species are eaten raw, while most commercial species are processed into a dry product called beche-de-mer or trepang. This dry product is exported to a central market such as Hong Kong and then re-exported to the consumers. In this review, recent statistics on the world sea cucumber fisheries, collected from different services, are detailed for each major fishing area. Case studies for each fishing area are also presented. Recent major changes in the Indo-Pacific fishery include the participation of new producer countries, the shift in the species being exploited, and an increase in the Chinese market. The expansion of the largely monospecific temperate North Pacific fisheries is also described. Statistics from Hong Kong, Singapore, Taiwan, and the Food and Agriculture Organization provide valuable information on the producer and importer countries. Particular attention is paid to the reciprocal trade of beche-de-mer between Hong Kong and Singapore. An evaluation of the world sea cucumber landings and beche-de-mer production is presented. Recent developments include an expansion of the Hong Kong market due to increased demand by China, the importance of Indonesia as a major world producer, and an increase in the fisheries of Tropical Pacific nations. This increase is best documented for New Caledonia and Fiji. Ways to improve the access and the reliability of the statistics for the sea cucumber fishery are discussed, as is the potential for management of artisanal fisheries.

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Time-lapse remote photo-sequences at 73-700 m depth off Palau, Western Caroline Islands, show that the caridean shrimp Heterocarpus laevigatus tends to be a solitary animal, occurring below ~350 m, that gradually accumulates around bait sites over a prolonged period. A smaller speies, H. ensifer, tends to move erratically in swarms, appearing in large numbers in the upper part of its range (<250 m) during the evening crepuscular period and disappearing at dawn. Trapping and photsequence data indicate the depth range of H. ensifer (during daylight) is ~250-550 M, while H. laevigatus ranges from 350 m to at least 800 m, along with the geryonid crab Chaceon granulatus. Combined trapping for Heterocarpus laevigatus and Chaceon granulatus, using a three-chamber box-trap and extended soak times (48-72 hr), may be an appropriate technique for small-scale deep-water fisheries along forereef slopes of Indo-Pacific archipelagoes.

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Classes perigosas é um conceito elaborado pela elite nacional em fins do século XIX, na tentativa de definir, assim, a massa pobre, oriunda, especialmente, do regime de escravidão que durou três séculos. Nossa proposta de estudo busca compreender a utilização atual desse conceito, propagado pelos aparelhos midiáticos, que resulta num processo de criminalização da pobreza e aviltamento crescente dos direitos humanos da parcela populacional que se encontra nessas condições. Como ponto vista teórico partimos da concepção de hegemonia em Gramsci, e a partir disso refletimos acerca de outro pensamento fundamental deste autor que trata sobre aparelhos privados de hegemonia, para, desta forma, compreendermos a importância do desenvolvimento dos meios de comunicação na construção dos processos hegemônicos que sustentam a ideologia da classe dominante. Indo além, buscaremos traçar um breve resgate histórico sobre o mito das classes perigosas no Rio de Janeiro e levantar um debate sobre a construção social do medo e sentimento de insegurança pública, o que legitima a atuação dos aparelhos coercitivos do Estado. Dito isto, pretendemos relacionar a questão apontada com o debate sobre os atuais mecanismos de controle social, explicitados e analisados, em seu discurso, através da exposição de notícias publicas em jornais de grande circulação em novembro de 2010.

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Este trabalho aborda, de maneira bem sucinta e objetiva, a história da evolução dos números desde o primeiro risco em um osso, até chegar na forma atual como os conhecemos. Ao longo de aproximadamente 30.000 anos de existência, os sistemas de numeração, suas bases e representações sofreram inúmeras modificações, adequando-se ao contexto histórico vigente. Podemos citar a mentalidade científica da época, a necessidade da conquista de territórios, religiões e crenças e necessidades básicas da vida cotidiana. Deste modo, mostramos uma corrente histórica que tenta explicar como e porque a ideia de número se modifica com o tempo, sempre tendo em vista os fatores que motivaram tais mudanças e quais benefícios (ou malefícios) trouxeram consigo. Com um capítulo dedicado a cada uma das mais importantes civilizações que contribuíram para o crescimento da matemática e, sempre que possível, em ordem cronológica de acontecimentos, o leitor consegue ter uma boa ideia de como uma civilização influencia a outra e como um povo posterior pôde apoiar-se nos conhecimentos adquiridos dos antepassados para produzir seus próprios algorítimos e teoremas.

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Esta dissertação pretende investigar de que forma idéias construídas socialmente impõem a heterossexualidade e afetam indivíduos não heterosexuais das ilhas Caribenhas, conforme ilustrado nos romances Memory Mambo, da Cubana-Americana Achy Obejas e Valmikis Daughters, da Trinitária-Canadense Shani Mootoo. Este trabalho se concentra na análise de políticas sexuais ligadas à homossexualidade tanto nas ilhas do Caribe quanto nos Estados Unidos da América. Em Memory Mambo, a protagonista Juani Casas deseja entender como sua condição de exilada cubana molda sua identidade sexual e como seu lesbianismo afeta seus relacionamentos familiares e amorosos. Reconstruindo sua história através de uma memória não confiável, Juani procura descobrir como sua sexualidade e sua nacionalidade estão ligadas, para que ela possa conciliar as duas. Em Valmikis Daughter, Viveka Krishnu e seu pai Valmiki Krishnu tentam esconder seus verdadeiros desejos por causa dos comportamentos supostamente corretos que foram designados tanto para homens quanto para mulheres em Trinidad, e mais especificamente na sociedade indo-caribenha. Pai e filha sofrem com a opressão e tentam não se tornarem vítimas de homofobia constante, ele escondendo sua sexualidade e ela deixando a ilha. Assim, através da representação literária, Obejas e Mootoo participam de uma discussão necessária sobre as consequencias das políticas sexuais na construção identitária de Caribenhos que vivem nas ilhas ou em destinos diaspóricos

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Invasive species generate significant environmental and economic costs, with maintenance management constituting a major expenditure. Such costs are generated by invasive Indo-Pacific lionfish (Pterois spp.) that further threaten already stressed coral reefs in the western Atlantic Ocean and Caribbean Sea. This brief review documents rapid range expansion and potential impacts of lionfish. In addition, preliminary experimental data from targeted removals contribute to debates about maintenance management. Removals at sites off Little Cayman Island shifted the size frequency distribution of remaining lionfish toward smaller individuals whose stomachs contained less prey and fewer fish. Fewer lionfish and decreased predation on threatened grouper, herbivores and other economically and ecologically important fishes represent key steps toward protecting reefs. However, complete evaluation of success requires long-term data detailing immigration and recruitment by lionfish, compensatory growth and reproduction of lionfish, reduced direct effects on prey assemblages, and reduced indirect effects mediated by competition for food. Preventing introductions is the best way to avoid impacts from invasive species and early detection linked to rapid response ranks second. Nevertheless, results from this case study suggest that targeted removals represent a viable option for shifting direct impacts of invasive lionfish away from highly vulnerable components of ecosystems.

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Nesta dissertação, apresentamos resultados da análise de um gás de elétrons bidimensional, confinado em um poço quântico parabólico de Ga_(1-x)Al_(x)As com campo magnético aplicado inclinado e intenso. Mostramos uma solução analítica exata para o caso de um gás de elétrons não interagente e provamos que o fator de Landé efetivo g*, que neste caso varia com a posição devido à própria variação da concentração de Al na liga GaAlAs, também contribui com um termo parabólico nas frequências normais, tornando-as dependente do spin. O termo normal do splitting Zeeman aparece, no entanto, com um fator g dado por aquele do GaAs. Indo além desse tratamento, incluímos um campo elétrico externo, aplicado paralelamente a direção de crescimento, de modo a modular a distribuição de cargas dentro do poço, e com isso controlar externamente os efeitos dos cruzamentos dos níveis. Calculamos numericamente os níveis de energia no poço parabólico quântico, variando o campo magnético aplicado e a inclinação do campo.

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The Indo-pacific panther grouper (Chromileptes altiveli) is a predatory fish species and popular imported aquarium fish in the United States which has been recently documented residing in western Atlantic waters. To date, the most successful marine invasive species in the Atlantic is the lionfish (Pterois volitans/miles), which, as for the panther grouper, is assumed to have been introduced to the wild through aquarium releases. However, unlike lionfish, the panther grouper is not yet thought to have an established breeding population in the Atlantic. Using a proven modeling technique developed to track the lionfish invasion, presented is the first known estimation of the potential spread of panther grouper in the Atlantic. The employed cellular automaton-based computer model examines the life history of the subject species including fecundity, mortality, and reproductive potential and combines this with habitat preferences and physical oceanic parameters to forecast the distribution and periodicity of spread of this potential new invasive species. Simulations were examined for origination points within one degree of capture locations of panther grouper from the United States Geological Survey Nonindigenous Aquatic Species Database to eliminate introduction location bias, and two detailed case studies were scrutinized. The model indicates three primary locations where settlement is likely given the inputs and limits of the model; Jupiter Florida/Vero Beach, the Cape Hatteras Tropical Limit/Myrtle Beach South Carolina, and Florida Keys/Ten Thousand Islands locations. Of these locations, Jupiter Florida/Vero Beach has the highest settlement rate in the model and is indicated as the area in which the panther grouper is most likely to become established. This insight is valuable if attempts are to be made to halt this potential marine invasive species

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The Indo-Pacific lionfish, Pterois miles and P. volitans, have recently invaded the U.S. east coast and the Caribbean and pose a significant threat to native reef fish communities. Few studies have documented reproduction in pteroines from the Indo-Pacific. This study provides a description of oogenesis and spawn formation in P. miles and P. volitans collected from offshore waters of North Carolina, U.S.A and the Bahamas. Using histological and laboratory observations, we found no differences in reproductive biology between P. miles and P. volitans. These lionfish spawn buoyant eggs that are encased in a hollow mass of mucus produced by specialized secretory cells of the ovarian wall complex. Oocytes develop on highly vascularized peduncles with all oocyte stages present in the ovary of spawning females and the most mature oocytes placed terminally, near the ovarian lumen. Given these ovarian characteristics, these lionfish are asynchronous, indeterminate batch spawners and are thus capable of sustained reproduction throughout the year when conditions are suitable. This mode of reproduction could have contributed to the recent and rapid establishment of these lionfish in the northwestern Atlantic and Caribbean.

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Lionfish, Pterois volitans and P. miles, are native to the Indo-Pacific and have recently invaded the Western Atlantic Ocean. Strategies for control of this invasion have included limited removal programs and promotion of lionfish consumption at both local and commercial scales. We demonstrate that lionfish meat contains higher levels of healthy n-3 fatty acids than some frequently consumed native marine fish species. Mean lionfish fillet yield was 30.5% of the total body wet weight, a value that is similar to that of some grouper and porgy species. A sensory evaluation indicated that lionfish meet the acceptability threshold of most consumers.

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The Indo-Pacific lionfishes, Pterois miles and P. volitans, are now established along the U.S. southeast coast, Bermuda, Bahamas, and are becoming established in the Caribbean. While these lionfish are popular in the aquarium trade, their biology and ecology are poorly understood in their native range. Given the rapid establishment and potential adverse impacts of these invaders, comprehensive studies of their biology and ecology are warranted. Here we provide a synopsis of lionfish biology and ecology including invasion chronology, taxonomy, local abundance, reproduction, early life history and dispersal, venomology, feeding ecology, parasitology, potential impacts, and control and management. This information was collected through review of the primary literature and published reports and by summarizing current observations. Suggestions for future research on invasive lionfish in their invaded regions are provided.

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Percophids are a family of small marine benthic fishes common over soft bottoms from inshore to the outer slopes in tropical to temperate regions of the Atlantic and in the Indo-West and southeast Pacific (Reader and Neira, 1998; Okiyama, 2000). Five species belonging to four genera have been recorded around the Salas y Gómez Ridge in the southeast Pacific, all of which are endemic to the area except for Chrionema chryseres, a species which also occurs off the Hawaiian Islands and Japan (Parin, 1985, 1990; Parin et al., 1997). Of these five species, larval stages have been described only for Osopsaron karlik and Chrionema pallidum (Belyanina 1989, 1990).

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In this study the author provided a synthesis of the most relevant aspects of fisheries in Mozambique and Indo-Pacific Region, discussed at the “Seminario sobre avaliaçāo de mananciais de atum na regiāo indo-pacifiqa-jacarta” held in Jakarta from 20 to 22 August 1984. Tens of documents belonging to the Department of Documentation and Information of the Fisheries Research Institute of Maputo and containing valuable information on the tuna fishing in Indo-Pacífic Region were studied in preparation of this seminar.

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One male and one female of Zozymodes cavipes (Dana, 1852) have revently been collected from the rocky shores near Karachi; the species is widely distributed in the Indo-Pacific region. It is, however, being reported for the first time from the pakistani coast of the northern Arabian Sea and thus fills the gap in the known distribution of the species. The pakistani material is housed in the Marine Reference Collection Centre, University of Karachi. The specimens are briefly descibed below. Only restricted synonym is given.