963 resultados para intensive system
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Includes index.
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[EN]Meagre, Argyrosomus regius A., is a new species for aquaculture in south Atlantic and Mediterranean regions, that can reach a mean fresh weight of 8.02±2.51g. at 95dah. However, hatchery techniques must be improved to optimize culture performance and larval quality. Eggs of meagre were cultured under intensive (75 indv.l-1 in 2m3 tanks) and semi-intensive system (7.5 indv.l-1 in 40m3 tanks) to evaluate the effect of the intensification on biological features, stress resistance and skeletal deformities. At 30dah, despite in semi-intensive system reared larvae a higher total length (19.08± 2.3mm vs 16.00±1.54mm), dry body weight (13.09± 2.43mg vs 6.46±0.52mg), and survival after the activity test (75.0± 13.8% vs 53.3±11.5%) was found, the use of intensive systems were also very suitable and cost-effective for larval rearing of this species
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[ES] Main deformities such as lordosis, opercular deformities and upper/lower jaws shortening are considered as quality descriptors in commercial marine fish fry production and seem to be related with larval culture conditions in early larval stages. The aim of this work was to obtain information about the contribution of the diet and rearing system to the apparition of these abnormalities in gilthead sea bream (Sparus aurata) larvae in semi-industrial scale facilities. For that purpose, two different larval rearing systems semi-intensive and intensive were compared; besides, two different rotifer enrichments, DHA Protein Selco, (Inve Aquaculture, Dendermonde, Belgium) (R1) and Red Pepper Paste, (Bernaqua bvba, Turnhout, Belgium) were tested in the intensive system. Biochemical composition of larvae, preys and commercial products was analysed. At 50 days post hatching six hundred fish per treatment were individually studied under stereoscope and deformity frequency recorded. Besides at 95 days post hatching fry were soft X ray monitored. Both rotifer enrichment and rearing system affected survival, growth and deformity frequency. Rearing system did not affect total larvae fatty acid content except at 20 dah, where DHA were significantly higher and EPA significantly lower in Semi-intensive system. A significantly lower percentage of deformity rates together with better survival and growth were obtained in the semi-intensive system. In dietary treatment, rotifer enrichment significantly affected larval survival. R1 rotifers enrichment significantly (P<0.05) improved survival when compared to fed R2 larvae. The content of DPA was significantly (P<0.05) higher in R2 fed larvae reflecting the R2 rotifers content of this fatty acid. The level of this FA tended to decrease in concordance with the rotifers replacement by artemia in the diet. The effects n-3-HUFA and DPA (22:5n-6) over larval survival and skeletal deformities development is discussed.
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Large scale wind power generation complicated with restrictions on the tie line plans may lead to significant wind power curtailment and deep cycling of coal units during the valley load periods. This study proposes a dispatch strategy for interconnected wind-coal intensive power systems (WCISs). Wind power curtailment and cycling of coal units are included in the economic dispatch analysis of regional systems. Based on the day-ahead dispatch results, a tie line power plan adjustment strategy is implemented in the event of wind power curtailment or deep cycling occurring in the economic dispatch model, with the objective of reducing such effects. The dispatch strategy is designed based on the distinctive operation characteristics of interconnected WCISs, and dispatch results for regional systems in China show that the proposed strategy is feasible and can improve the overall system operation performance.
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Bio-floc shrimp culture systems have been investigated in an attempt to optimize water use and prevent the discharge of effluent into the environment. The importance of microalgae in maintaining water quality and nutrition of the shrimp is well known in conventional systems; however, its maintenance amid bio-flocs and its role in the shrimp performance in this system are still poorly understood. The aim of this study was to evaluate the contribution of diatoms in the performance of Litopenaeus vannamei reared during the nursery phase in intensive system with minimal water exchange. Shrimp (0.31 ± 0.10 g) were reared among diatoms, bio-flocs and the combination of the two forming the mixture medium. The survival of shrimp was high in all treatments (90–97%). However, the shrimp reared among diatoms showed higher weight gain (P\0.05) and feed conversion ratio significantly more efficient, reaching a value of 0.47. The results indicate the importance of diatoms in bio-floc culture systems and points out to future research in an attempt to maintain a constant presence of these microalgae in culture medium without requiring successive inoculations.
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This report describes the general background to the project, defines the stations from which data sets have been obtained and lists the available data. The project had the following aims: To develop a more accurate and less labour-intensive system for the collection and processing of water temperature data from a number of stations within a stream/river system, and to use the River North Tyne downstream of the Kielder impoundment as a test bed for the system. This should yield useful information on the effects of impoundment upon downstream water temperatures.
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A investigação em apreço tem como horizonte de ocorrência o espaço inter-organizacional onde as empresas se relacionam entre si, com os seus fornecedores, canais e Clientes. É pretendido estudar o actual estado das parcerias inter-organizacionais do sector segurador nacional e definir uma estratégia de desenvolvimento integrado dos sistemas de valor. Com base num modelo de análise ancorado na (1) racionalidade económica inscrita na TCE (teoria dos custos de transacção) e (2) na óptica das Capacidades Dinâmicas, é proposto o Modelo GPS (Gestão Integrada de Parcerias) compaginável com uma visão holística e dinâmica. A metodologia de verificação empírica compreendeu (1) recolha de dados através de questionário, dirigido a Companhias e Parceiros e (2) entrevistas semi-estruturadas. A análise descritiva dos dados permitiu validar o modelo GPS e caracterizar um sistema de valor heterogéneo, complexo e diversificado relativamente à natureza e intensidade de relacionamentos. O sistema de relacionamentos foi enquadrado numa escala de maturidade onde foram posicionadas as várias práticas de gestão de parcerias. Actualmente nos seguros estamos perante um sistema mais economic-intensive, transaccional, do que knowledge-intensive. No teste de hipóteses, efectuado com a ferramenta SPSS, assinalam-se as correlações que se esperavam encontrar, bem como as (principais) ausências. De facto, a ausência de vestígios de correlação entre governance social/confiança e colaboração nos seguros não era esperada e constitui uma chamada de atenção para uma dimensão sub-explorada, conducente a um quadro tensional. No final, com base na realidade captada, foram traçadas recomendações de desenvolvimento dos sistemas de valor visando alcançar níveis colaborativos mais eficazes, assentes na força dos laços fortes. Todavia, esta nova narrativa de gestão não é neutral face aos modelos vigentes, implicando algum grau de ruptura. A continuação de especialização em actividades core, desconstruindo de forma (mais) pronunciada a cadeia de valor, secundada por maior níveis de colaboração e socialização entre pares, são elementos constitutivos da realidade futura. Vendo para além da linha do horizonte, os gestores seguradores não podem ficar indiferentes à projecção de uma matriz de fundo de relacionamentos mais colaborativos enquanto terreno fértil de inovação e renovação de fontes de vantagem competitiva.
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In ago-pastoral systems of the semi-arid West African Sahel, targeted applications of ruminant manure to the cropland is a widespread practice to maintain soil productivity. However, studies exploring the decomposition and mineralisation processes of manure under farmers' conditions are scarce. The present research in south-west Niger was undertaken to examine the role of micro-organisms and meso-fauna on in situ release rates of nitrogen (N), phosphorus (P) and potassium (K) from cattle and sheep-goat manure collected from village corrals during the rainy season. The results show tha (1) macro-organisms played a dominant role in the initial phase of manure decomposition; (2) manure decomposition was faster on crusted than on sandy soils; (3) throughout the study N and P release rates closely followed the dry matter decomposition; (4) during the first 6 weeks after application the K concentration in the manure declined much faster than N or P. At the applied dry matter rate of 18.8 Mg ha^-1, the quantities of N, P and K released from the manure during the rainy season were up to 10-fold larger than the annual nutrient uptake of pearl millet (Pennisetum glaucum L.), the dominant crop in the traditional agro-pastoral systems. The results indicate considerable nutrient losses with the scarce but heavy rainfalls which could be alleviated by smaller rates of manure application. Those, however, would require a more labour intensive system of corralling or manure distribution.
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The Nyasaland Emergency in 1959 proved a decisive turning point in the history of the Federation of Rhodesia and Nyasaland, which from 1953 to 1963 brought together the territories of Northern Rhodesia (Zambia), Southern Rhodesia (Zambia) and Nyasaland (Malawi) under a settler-dominated federal government. The British and Nyasaland governments defended the emergency by claiming to have gathered intelligence which showed that the Nyasaland African Congress was preparing a campaign of sabotage and murder. The Devlin Commission, appointed to investigate the emergency, dismissed the evidence of a ‘murder plot’, criticised the Nyasaland government's handling of the Emergency and, notoriously, described Nyasaland as a ‘police state’. This article has two principal aims. First, using the recently declassified papers of the Intelligence and Security Department (ISD) of the Colonial Office, it seeks to provide the first detailed account of what the British government knew of the intelligence relating to the ‘murder plot’ and how they assessed it, prior to the outbreak of the emergency. It demonstrates that officials in the ISD and members of the Security Service adopted a far more cautious attitude towards the intelligence than did Conservative ministers, and had greater qualms about allowing it into the public domain to justify government policy. Second, the article examines the implications of Devlin's use of the phrase ‘police state’ for Nyasaland and for the late colonial state in general. It contrasts Devlin's use of the term with that of security experts in the ISD, who routinely applied it to policing systems that diverged from their own preferred model. Hence, whereas Devlin compared policing in Nyasaland unfavourably with that in Southern Rhodesia, implying, ironically, that Nyasaland was ‘under-policed’ (because there were fewer police per head of population in Nyasaland than in Southern Rhodesia), the ISD regarded the intensive system of policing operated by the British South Africa Police in Southern Rhodesia as characteristic of a ‘police state’. The article suggests that the frequent use of the term ‘police state’ was indicative of broader anxieties about what Britain's legacy would be for the post-independence African state.
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Neste trabalho foi realizada a análise econômica da produção de juvenis de tilápia-do-nilo em tanques-rede utilizando-se diferentes densidades de estocagem. O experimento foi desenvolvido em área aquícola, em delineamento de blocos casualizados, com quatro densidades de estocagem (100, 200, 300 e 400 peixes m-3), avaliadas com seis repetições, em dois períodos de criação: de março a abril de 2005 (52 dias - peso inicial de 43,08 ± 2,98 g e peso final de 262,14 ± 47,86 g) e de março a abril de 2006 (58 dias - peso inicial de 43,16 ± 5,34 g e peso final 314,24 ± 73,30 g). Foram avaliadas as seguintes variáveis econômicas: custo da ração mais custo do juvenil dividido pela biomassa, em R$ kg-1; porcentagem do custo da ração por quilo de peixe produzido sobre o preço de venda; porcentagem do custo do juvenil por quilo de peixe produzido sobre o preço de venda e; porcentagem dos custos da ração mais do juvenil por quilo de peixe produzido sobre o preço de venda. da menor densidade de estocagem (100) para a maior (400), ocorreu diminuição no ganho de peso diário e elevação do índice de conversão alimentar aparente, mas essa redução não comprometeu a taxa de sobrevivência. Entretanto, o ganho de biomassa aumentou com o adensamento de peixes. As maiores receitas líquidas foram obtidas nas densidades de estocagem de 100 e 200 peixes m-3. Os preços não remuneraram os custos operacionais (efetivo e total) em maiores densidades (300 e 400 peixes m-3). Os melhores resultados para a produção de juvenis de tilápia-do-nilo foram obtidos com densidades de até 200 peixes m-3.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Por ser de grande importância o conhecimento de valores séricos referenciais do mineralograma e do proteinograma, a sua utilização na medicina veterinária, e a escassez de trabalhos brasileiros relacionados à espécie caprina, este estudo objetivou determinar e comparar os níveis séricos de cálcio, fósforo, sódio, potássio e proteínas (proteína total, albumina, globulina e a relação albumina/globulina) em caprinos fêmeas da raça Parda Alpina, em três idades diferentes. Foram utilizadas 30 fêmeas caprinas da raça Parda Alpina criadas em regime intensivo, sendo separadas em três grupos: Grupo 1 - 10 fêmeas jovens com idade de quatro meses; Grupo 2 - 10 fêmeas adultas jovens com idade de 18 meses; Grupo 3 - 10 fêmeas adultas lactantes com idade de 24 a 60 meses. Os animais foram avaliados por meio de exames clínico e coproparasitológico. Foram encontrados os seguintes valores médios de cálcio, fósforo, sódio e potássio no grupo G1: 10,10± 1,70, 10,13± 2,04, 151± 3,30 e 5,16± 0,41; no grupo G2: 10,36± 0,94, 7,49± 1,34, 145,9± 3,35 e 4,56± 0,48; e para o grupo G3: 9,47± 1,45, 5,90± 1,21, 153,3± 5,17 e 4,20± 0,55. Para as variáveis proteína total sérica, albumina, globulina e relação albumina/globulina foram encontrados os seguintes valores médios, para o grupo G1: 6,29± 0,94, 3,5± 10,41, 2,78± 0,95 e 1,40± 0,48; para o grupo G2: 7,27± 0,73, 4,92± 1,06, 3,06± 0,56, 1,43± 0,44; e para o grupo G3: 7,14± 0,84, 3,70± 0,20, 3,44± 0,79 e 1,14± 0,30. A análise estatística dos dados demonstra que existe influência da faixa etária nas variáveis fósforo, sódio, potássio, proteína total e albumina.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)