844 resultados para Production (Economic theory)


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In this paper we present livestock breeding developments that could be taken into consideration in the genetic improvement of farmed aquaculture species, especially in freshwater fish. Firstly, the current breeding objective in aquatic species has focused almost exclusively on the improvement of body weight at harvest or on growth related traits. This is unlikely to be sufficient to meet the future needs of the aquaculture industry. To meet future demands breeding programs will most likely have to include additional traits, such as fitness related ones (survival, disease resistance), feed efficiency, or flesh quality, rather than only growth performance. In order to select for a multi-trait breeding objective, genetic variation in traits of interest and the genetic relationships among them need to be estimated. In addition, economic values for these traits will be required. Generally, there is a paucity of data on variable and fixed production costs in aquaculture, and this could be a major constraint in the further expansion of the breeding objectives. Secondly, genetic evaluation systems using the restricted maximum likelihood method (REML) and best linear unbiased prediction (BLUP) in a framework of mixed model methodology could be widely adopted to replace the more commonly used method of mass selection based on phenotypic performance. The BLUP method increases the accuracy of selection and also allows the management of inbreeding and estimation of genetic trends. BLUP is an improvement over the classic selection index approach, which was used in the success story of the genetically improved farmed tilapia (GIFT) in the Philippines, with genetic gains from 10 to 20 per cent per generation of selection. In parallel with BLUP, optimal genetic contribution theory can be applied to maximize genetic gain while constraining inbreeding in the long run in selection programs. Thirdly, by using advanced statistical methods, genetic selection can be carried out not only at the nucleus level but also in lower tiers of the pyramid breeding structure. Large scale across population genetic evaluation through genetic connectedness using cryopreserved sperm enables the comparison and ranking of genetic merit of all animals across populations, countries or years, and thus the genetically superior brood stock can be identified and widely used and exchanged to increase the rate of genetic progress in the population as a whole. It is concluded that sound genetic programs need to be established for aquaculture species. In addition to being very effective, fully pedigreed breeding programs would also enable the exploration of possibilities of integrating molecular markers (e.g., genetic tagging using DNA fingerprinting, marker (gene) assisted selection) and reproductive technologies such as in-vitro fertilization using cryopreserved spermatozoa.

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Nas últimas décadas a preocupação com as questões ambientais tem se tornado mais presentes em diversos contextos sociais. As transformações de origem antrópica operadas no ambiente se intensificaram com os adventos tecnológicos característicos da modernidade que, em função da conjuntura política, econômica e social do capitalismo, consolidou uma lógica de dominação que, ao contrário do que enunciava, aprofundou e tornou mais complexo formas excludentes, discriminatórias e destrutivas de se relacionar com o outro e com o externo. Frente a isso, como movimento para diminuir ou sanar tais questões referentes a relação violenta do homem com o ambiente, a educação ambiental emerge apoiada em diferentes campos do conhecimento, manifestando-se de diversas formas. O presente estudo visa abordar essa temática analisando aspectos curriculares do curso de Licenciatura em Geografia com Ênfase em Meio Ambiente da Faculdade de Educação da Baixada Fluminense que se constitui propondo-se a formar de docentes de geografia que sejam também educadores ambientais. O ementário do curso foi analisado de modo a observar de que maneira as questões ambientais manifestam-se nos textos. Para isso, nos pautamos, sobretudo, na teoria do discurso, de Ernesto Laclau, e nas discussões e concepções sobre políticas curriculares construídas por Stephen Ball, Elizabeth Macedo e Alice Lopes. Buscamos compreender de que forma as significações ou associações presentes nas ementas contribuem para a formação de educadores ambientais, e sob qual perspectiva de educação ambiental isso ocorre. Analisamos o documento indicado cumprindo uma exigência de delimitação, uma vez que estamos cientes (e esse é um princípio importante da nossa abordagem) que a construção discursiva não se limita ao que é dito/escrito, mas se dá na interação social, arrolada pelas/nas disputas hegemônicas por significação e enunciação.

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The potential for growth overfishing in the white shrimp, Litopenaeus setiferus, fishery of the northern Gulf of Mexico appears to have been of limited concern to Federal or state shrimp management entities, following the cataclysmic drop in white shrimp abundance in the 1940’s. As expected from surplus production theory, a decrease in size of shrimp in the annual landings accompanies increasing fishing effort, and can eventually reduce the value of the landings. Growth overfishing can exacerbate such decline in value of the annual landings. We characterize trends in size-composition of annual landings and other annual fishery-dependent variables in this fishery to determine relationships between selected pairs of these variables and to determine whether growth overfishing occurred during 1960–2006. Signs of growth overfishing were equivocal. For example, as nominal fishing effort increased, the initially upward, decelerating trend in annual yield approached a local maximum in the 1980’s. However, an accelerating upward trend in yield followed as effort continued to increase. Yield then reached its highest point in the time series in 2006, as nominal fishing effort declined due to exogenous factors outside the control of shrimp fishery managers. The quadratic relationship between annual yield and nominal fishing effort exhibited a local maximum of 5.24(107) pounds (≈ MSY) at a nominal fishing effort level of 1.38(105) days fished. However, annual yield showed a continuous increase with decrease in size of shrimp in the landings. Annual inflation-adjusted ex-vessel value of the landings peaked in 1989, preceded by a peak in annual inflation-adjusted ex-vessel value per pound (i.e. price) in 1983. Changes in size composition of shrimp landings and their economic effects should be included among guidelines for future management of this white shrimp

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The United States' increasing competitive advantage in international seafood trade in Alaska walleye pollock. Theragra chalcogramma, has contributed to higher prices for surimi-based goods and structural changes in seafood production and trade in Japan. The objectives of this analytical investigation include: 1) Evaluation of the role reversal of Japan and the United States in international seafood trade and 2) quantification of the impact of rising prices of frozen surimi on household consumption of surimi-based foods in Japan. This study documents Japan's regression from "seafood self-sufficiency" to increasing dependence on imported products and raw materials. In particular, Japan's growing dependence on American fishermen and seafood producers is described. Surimi production by the United States, and its emerging dominance over Japanese sources of supply, are especially significant. Results of the analysis suggest that Japanese consumer demand for surimi-based food stuffs correlates directly with "competitive" food prices, e.g., pork, chicken, and beef, and inversely with personal income. Also revealed is how rising household income and relative price shifts among competing animal protein sources in the Japanese diet have contributed to declining household consumption of surimi-based foods, specifically, and a shift away from seafoods in favor of beef, in general. The linkages between, for example. Japanese domestic seafood production and consumption, international trade in marine products, and resource management decisions in the U.S. EEZ present a picture of a changing global marketplace. Increasingly, actions in one arena will have perhaps profound implications in the others.

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Shrimp fishermen trawling in the Gulf of Mexico and south Atlantic inadvertently capture and kill sea turtles which are classified as endangered species. Recent legislation requires the use of a Turtle Excluder Device(TED) which, when in place in the shrimp trawl, reduces sea turtle mortality. The impact of the TED on shrimp production is not known. This intermediate analysis of the TED regulations using an annual firm level simulation model indicated that the average Texas shrimp vessel had a low probability of being an economic success before regulations were enacted. An assumption that the TED regulations resulted in decreased production aggravated this condition and the change in Ending Net Worth and Net Present Value of Ending Net Worth before and after a TED was placed in the net was significant at the 5 percent level. However, the difference in the Internal Rate of Return for the TED and non-TED simulations was not significant unless the TED caused a substantial change in catch. This analysis did not allow for interactions between the fishermen in the shrimp industry, an assumption which could significantly alter the impact of TED use on the catch and earnings of the individual shrimp vessel.

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O trabalho busca na teoria dos sistemas de Niklas Luhmann, tal como desenvolvida por Gunther Teubner, Marcelo Neves e outros doutrinadores, elementos para explicar as relações entre os subsistemas jurídico, político e econômico na sociedade contemporânea. Com base nas ferramentas teóricas obtidas, revisa o conceito de constituição econômica como a relação de acoplamento estrutural entre o direito e a economia, e a Constituição do Estado como a relação de acoplamento estrutural entre o direito e a política. As crises econômicas são então explicadas pelas tendências inflacionárias na produção de símbolos e pelos choques entre racionalidades sistêmicas parciais. A crise de 2008 consolida a constatação de que a globalização restringe a capacidade de influência da política e do direito sobre o sistema econômico desterritorializado. Em vista disso, propõe-se a adoção da teoria do constitucionalismo societal de Teubner como proposta para a democracia no século XXI; através dela, é possível reconhecer a constitucionalização no interior de cada subsistema social e o desenvolvimento de foros de razão pública internos, nos quais a política pode ser desenvolvida de forma autônoma em relação à política institucionalizada do Estado. Finalmente, vê-se como o combate à crise econômica invariavelmente redesenha os papéis dos Poderes de Estado, reconhecendo certa liberdade ao Executivo, embora isso não signifique ausência de quaisquer freios e contrapesos.

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O presente trabalho busca compreender as ressignificações do discurso pedagógico contemporâneo a partir da análise dos slogans que circularam na recente Conferência Nacional de Educação (CONAE), como modo de problematizar os projetos ideológicos em disputa por hegemonia no campo da educação nacional. Situado no entrecruzamento entre os campos da linguagem, da ideologia e do poder como hegemonia, toma a teoria enunciativa de Mikhail Bakhtin e a Análise Crítica do Discurso (ACD), nos termos em que formulada por Norman Fairclough, como propostas teórico-metodológicas. No escopo de um diálogo tecido entre os autores, assume a linguagem como parte irredutível da vida social, em duas abordagens que propõem as noções de discurso e de poder em perspectiva crítica. Pautado na imersão da pesquisadora na CONAE, esfera de produção-circulação do discurso pedagógico contemporâneo, este trabalho assume o texto como material privilegiado de análise, focalizando documentos oficiais e pronunciamentos político-governamentais. Dois discursos nodais foram identificados: o da democratização e o da qualidade. Em relação ao primeiro, são analisados os pressupostos assumidos e a constituição histórica de um campo de sentidos que inclui artifícios retóricos. Em relação ao segundo, é dado tratamento crítico ao léxico associado à qualidade em suas sucessivas adjetivações. A partir de ambos os discursos foram analisados dois slogans. O primeiro deles denominado Educação para todos!, Todos pela Educação! aponta para dois deslocamentos semânticos: 1) do direito à educação para o direito à qualidade; e 2) da perspectiva da igualdade para a de uma inclusão baseada no conceito da diferença. O segundo slogan denominado O protagonista, professor! aponta para um lugar contraditório ocupado pelo professor, em que a exortação não se coaduna com suas condições materiais de existência. Para abordar a constituição ideológica deste lugar, nos seus sentidos hegemônicos, são analisados: os discursos da OCDE e imagens de professores na mídia como expressões das relações entre os contextos micro e macro. Para a compreensão dos slogans é situado o binômio informação-conhecimento como cronotopo-chave da contemporaneidade. É nesse cenário que as expectativas relativas à produção do conhecimento são articuladas a exigências do sistema produtivo, sendo a educação concebida como instrumento de racionalidade econômica. Desse modo, o movimento analítico questiona, para além da positividade aparente, a forma como os slogans ganham centralidade no discurso pedagógico contemporâneo, na tentativa de perceber sentidos que interpelam sujeitos e sistemas de ensino e vão sendo naturalizados, até que, tomados como necessários, afastam possibilidades de crítica

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A presente dissertação busca realizar a descrição e sistematização de categorias analíticas que contribuam com análises sobre as relações econômicas, políticas e sociais que sustentam a forma como se constituem historicamente no Brasil o Estado e as políticas públicas na área social, com especial atenção para a área de saúde. Tal objetivo se constituiu na observação das novas estratégias utilizadas pelo Estado para a execução de ações na área de saúde, como os projetos sociais. Tomamos o método do materialismo histórico dialético como referencial teórico, com especial atenção às categorias da filosofia da práxis práxis, totalidade, historicidade e contradição e a teoria marxista sobre a formação do Estado capitalista e suas transformações históricas, com ênfase na teoria sobre o Estado ampliado e o papel da sociedade civil na disputa entre as classes pela hegemonia. No segundo capítulo, abordamos a organização contemporânea do Estado brasileiro, buscando discutir escolhas políticas e econômicas, suas implicações para a organização dos trabalhadores e para a correlação de forças na disputa entre as classes. Foi feito breve levantamento histórico sobre os modelos de desenvolvimento econômico e social nas sociedades contemporâneas, com atenção à consolidação do ideário neoliberal, sua conceituação, as adequações que sofreu a partir do final dos anos 1990 e sua relação com a ideologia desenvolvimentista. Dedicamos o terceiro capítulo ao conceito de capital social, como maneira de compreender a atual forma de desenvolvimento das políticas públicas e em especial as políticas de saúde. A partir deste conceito buscou-se compreender a relação entre Estado e sociedade civil na atualidade e como este influencia as transformações por que passaram o Estado e as políticas sociais. Abordou-se o desenvolvimento das políticas públicas da área social no Estado brasileiro até sua conformação no neoliberalismo; as concepções de saúde em disputa na sociedade brasileira, focando no conceito ampliado de saúde e no de determinação social da saúde; e de que forma estes conceitos são impactados pelas mudanças no contexto do neoliberalismo. Finalmente, foi possível observar como as orientações neoliberais alteraram significativamente a forma de organização e atuação do Estado, a concepção e aplicação de políticas públicas, bem como as políticas de saúde e seu ideário. Mudanças que fizeram pender a atuação do Estado ainda mais a favor dos interesses do capital.

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In this report we have attempted to evaluate the ecological and economic consequences of hypoxia in the northern Gulf of Mexico. Although our initial approach was to rely on published accounts, we quickly realized that the body of published literature deahng with hypoxia was limited, and we would have to conduct our own exploratory analysis of existing Gulf data, or rely on published accounts from other systems to infer possible or potential effects of hypoxia. For the economic analysis, we developed a conceptual model of how hypoxia-related impacts could affect fisheries. Our model included both supply and demand components. The supply model had two components: (1) a physical production function for fish or shrimp, and (2) the cost of fishing. If hypoxia causes the cost of a unit of fishing effort to change, then this will result in a shift in supply. The demand model considered how hypoxia might affect the quality of landed fish or shrimp. In particular, the market value per pound is lower for small shrimp than for large shrimp. Given the limitations of the ecological assessment, the shallow continental shelf area affected by hypoxia does show signs of hypoxia-related stress. While current ecological conditions are a response to a variety of stressors, the effects of hypoxia are most obvious in the benthos that experience mortality, elimination of larger long-lived species, and a shifting of productivity to nonhypoxic periods (energy pulsing). What is not known is whether hypoxia leads to higher productivity during productive periods, or simply to a reduction of productivity during oxygen-stressed periods. The economic assessment based on fisheries data, however, failed to detect effects attributable to hypoxia. Overall, fisheries landings statistics for at least the last few decades have been relatively constant. The failure to identify clear hypoxic effects in the fisheries statistics does not necessarily mean that they are absent. There are several possibilities: (1) hypoxic effects are small relative to the overall variability in the data sets evaluated; (2) the data and the power of the analyses are not adequate; and (3) currently there are no hypoxic effects on fisheries. Lack of identified hypoxic effects in available fisheries data does not imply that effects would not occur should conditions worsen. Experience with other hypoxic zones around the globe shows that both ecological and fisheries effects become progressively more severe as hypoxia increases. Several large systems around the globe have suffered serious ecological and economic consequences from seasonal summertime hypoxia; most notable are the Kattegat and Black Sea. The consequences range from localized loss of catch and recruitment failure to complete system-wide loss of fishery species. If experiences in other systems are applicable to the Gulf of Mexico, then in the face of worsening hypoxic conditions, at some point fisheries and other species will decline, perhaps precipitously.

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This paper presents a resume of the work carried on the production of 10 million major carp fry by stocking at the rate of 10 million spawn per hectare in 38 nursery ponds covering 2.1 ha. water spread area at Khutelabhata fish seed farm, Durg, Madhya Pradesh. Observations made on the effect of various types of feed on survival and growth rate of Indian Major carp fry in nurseries are reported. Physico-chemical parameters and plankton populations in the three sets of nurseries are given. The experiments indicates that optimum survival rate of fry can be obtained by feeding tender spawn with animal protein feed. The economic viability of the experiment discussed shows that for a little increase in the expenditure on improved artificial food the survival and growth of fry can be enhanced.

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The experiment was conducted at BRRI Regional Station, Habiganj during 1994-95 to evaluate the growth and economic performance of Nile tilapia, Oreochromis niloticus, fish reared in the field of irrigated boro rice with different fertilizer levels. Grain yield of rice was not affected by fish culture. It was observed that 50% of recommended fertilizer was enough to produce increased rice yield (8-10 t/ha) at floodplain environment and additional yield was obtained with the increasing fertilizer rates. Results further indicated that O. niloticus could successfully be reared in the field of irrigated boro rice with recommended fertilizer level. Larger size of fingerlings at release had improved recovery percent, body weight gain and higher fish yield. Results also revealed that rice + fish production system produced higher net return than the system with rice alone.

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Several important advances have been made in our knowledge both regarding the factors which determine fertility in tropical lakes and the fish that live in them. As a result of our investigations a new theory has been put forward regarding the part played by animals in the bionomics of a lake; this theory, stated somewhat baldly, is that within certain limits the greater the number of animals in a shallow tropical lake, the greater becomes its potential fertility, and therefore the greater the number of animals it can support. The theory arises as a logical conclusion, once we accept the fact that the rate of production in such a lake is determined by the rate at which organic matter is decomposed. Bottom deposits which consist mainly of vegetable matter decompose slowly, whereas deposits which contain a high proportion of matter of animal origin decompose more rapidly. Thus the more animals in a lake, particularly animals which feed on plant material, the faster the biological cycle can proceed and the greater the density of animals it can support. This new concept will have a very profound influence on our ideas concerning the consequences of overfishing tropical waters. It also shows that efforts must be made to encourage and protect all herbivorous and detritus feeding animals, whether they be copepods, fish, or hippopotami, and whether they are of immediate economic importance or not.

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Economic aspects of producing liquid and dried silage from silver belly (Leiognathus splendens) in Sri Lanka are considered. A discounted cash flow analysis for the production of a dried fish silage/rice bran product suitable for use in compounded poultry feeds shows that the internal rate of return for a 10-year project would be between 34-77% and for a 5-year project between 26-73%. Thus it is concluded that the project would be extremely profitable.

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The effect of various factors on spawn and fingerlings production in government and private farms was measured in this study. Primary data were collected from 45 private and 11 government farms from 9 selected districts covering major fish seed producing areas of Bangladesh. Results from Cobb-Douglas production function analysis indicated that the included variables had some positive impacts on returns from spawn and fingerlings. No input was found to be over used and increasing returns to scale was observed. Tabular analysis indicated that higher amount of input use produced higher level of yield, gross return and net return. The government farms were under utilized. For increased supply of fish seeds in the country more amount of specified inputs (feed and fertilizer) should be used for producing spawn and fingerlings especially in government farms.