849 resultados para Viêt Nam


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El presente estudio se realizó con el objetivo de evaluar el efecto de las vitaminas y minerales en la fase preparto para reducir la incidencia del anestro en vacas pertenecientes a la finca San Cristóbal del municipio de Camoapa. El trabajo experimental se utilizó un diseño completamente aleatorio (D.C.A), el que está compuesto por un lote de 24 animales dividido en 3 grupos, cada grupo formado por 8 animales seleccionados al azar y sometidos a los siguientes tratamientos Tratamiento 1: Pecutrin, Tratamiento 11: Selfos plus + vit. AD3E y Tratamiento III: Control. Obteniendo como resultados, los animales que se les suministró Pecutrin presentan celos a los 116 días, mientras que los animales tratados con Selfos plus presentaron celos a los 80 días, y los no tratados presentaron celo a los 180 días, obteniéndose que con el tratamiento Selfos plus se redujo el puerperio en 100 días por animal. El intervalo parto primer celo comprendió entre 54 - 180 días, los animales tratados con Pecutrin correspondieron a una duración entre 62-130 días, mientras los tratados con Selfos plus+ vit. AD3E correspondieron a una duración de 54- 100 días, mientras que los no tratados fueron de 180 días. Según el análisis del costo de la dosis se puede decir que el Selfos plus+ vit. AD3E es un mineral económico para los productores.

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Comments on possible improvements to carp culture in Andhra Pradesh. Aquaculture and environmental issues in the region of Nai Lagoon, Ninh Hai district,Ninh Thuan province, Viet Nam. Climate change impacts on fi sheries and aquaculture. New initiatives in fisheries extension. Selection potential for feed efficiency in farmed salmonids. Freshwater prawn hatcheries in Bangladesh: Concern of broodstock. Production of Cirrhinus molitorella and Labeo chrysophekadion for culture based fisheries development in Lao PDR 2: Nursery culture and grow-out. Mussel farming: alternate water monitoring practice. Benefit-cost analysis for fi ngerling production of kutum Rutilus frisii kutum (Kamensky, 1901)in 2005 in Iran. The effects of feeding frequency on FCR and SGR factors of the fry of rainbow trout,Oncorhynchus mykiss. Asia-Pacific Marine Finfish Aquaculture Network Magazine: The use of poultry by-product meals in pelleted feed for humpback grouper. Production update – marine finfish aquaculture in the Asia-Pacific region. Crustacean parasites and their management in brackishwater finfish culture. NACA Newsletter

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Recently, the size dependence of mechanical behaviors, particularly the yield strength and plastic deformation mode, of bulk metallic glasses (BMG) has created a great deal of interest. Contradicting conclusions have been drawn by different research groups, based on various experiments on different BMG systems. Based on in situ compression transmission electron microscopy (TEM) experiments on Zr41Ti14Cu12.5Ni10Be22.5 (Vit 1) nanopillars, this paper provides strong evidence that shear banding still prevails at specimen length scales as small as 150 nm in diameter. This is supported by in situ and ex situ images of shear bands, and by the carefully recorded displacement bursts under load control its well as load drops under displacement control. Finite element modeling of the stress state within the pillar shows that the unavoidable geometry constraints accompanying such experiments impart a strong effect on the experimental results, including non-uniform stress distributions and high level hydrostatic pressures. The seemingly improved compressive ductility is believed to be due to such geometry constraints. Observations underscore the notion that the mechanical behavior of metallic glasses, including strength and plastic deformation mode, is size independent at least in Vit 1. (C) 2009 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

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The uniqThe unique lamellar chips formed in turning–machining of a Vit 1 bulk metallic glass (BMG) are found to be due to repeated shearband formation in the primary shear zone (PSZ). A coupled thermomechanical orthogonal cutting model, taking into account force, free volume and energy balance in the PSZ, is developed to quantitatively characterize lamellar chip formation. Its onset criterion is revealed through a linear perturbation analysis. Lamellar chip formation is understood as a self-sustained limit-cycle phenomenon: there is autonomous feedback in stress, free volume and temperature in the PSZ. The underlying mechanism is the symmetry breaking of free volume flow and source, rather than thermal instability. These results are fundamentally useful for machining BMGs and even for understanding the physical nature of inhomogeneous flow in BMGs.ue lamellar chips formed in turning–machining of a Vit 1 bulk metallic glass (BMG) are found to be due to repeated shearband.

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We report an intriguing observation that the interaction of brittle nanoscale periodic corrugations (NPCs) can lead to the formation of ductile dimples on the dynamic fracture surface of a tough Vit 1 bulk metallic glass (BMG) under high-velocity plate impact. A “beat” phenomenon due to superposition of simple harmonic vibrations, approximately characterizing NPCs, is proposed to explain this unusual brittle-to-ductile transition. The present results agree well with our previously revealed energy dissipation mechanism in the fracture of BMGs.

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The interaction of SO_2 with γ - Al_2O_3 and the deposition of H_2 permselective SiO_2 films have been investigated. The adsorption and oxidative adsorption of SO_2 on γ - Al_2O_3 have been examined at temperatures 500-700°C by Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). At temperatures above 500°C most of SO_2 adsorbed on the strong sites on alumina. The adsorbed SO_2 species was characterized by an IR band at 1065 cm^(-1). The equilibrium coverage and initial rate of adsorption decreased with temperature suggesting a two-step adsorption. When γ - Al_2O_3 was contacted with a mixture of SO_2 and O_2, adsorption of SO_2 and oxidation of the adsorbed SO_2 to a surface sulfate characterized by broad IR bands at 1070 cm^(-1), 1390 cm^(-1) took place. The results of a series of TGA experiments under different atmospheres strongly suggest that surface SO_2 and surface sulfate involve the same active sites such that SO_2 adsorption is inhibited by already formed sulfate. The results also indicate a broad range of site strengths.

The desorption of adsorbed SO_2 and the reductive desorption of oxidatively adsorbed SO_2 have been investigated by microreactor experiments and thermogravimetric analysis (TGA). Temperature programmed reduction (TPR) of adsorbed SO_2 showed that SO_2 was desorbed without significant reaction with H_2 when H_2 concentration was low while considerable reaction occurred when 100% H_2 was used. SO_2 adsorbed on the strong sites on alumina was reduced to sulfur and H_2S. The isothermal reduction experiments of oxidatively adsorbed SO_2 reveal that the rate of reduction is very slow below 550°C even with 100% H_2. The reduction product is mainly composed of SO_2. TPR experiments of oxidatively adsorbed SO_2 showed that H_2S arose from a sulfate strongly chemisorbed on the surface.

Films of amorphous SiO_2 were deposited within the walls of porous Vycor tubes by SiH_4 oxidation in an opposing reactants geometry : SiH_4 was passed inside the tube while O_2 was passed outside the tube. The two reactants diffused opposite to each other and reacted within a narrow front inside the tube wall to form a thin SiO_2 film. Once the pores were plugged the reactants could not reach each other and the reaction stopped. At 450°C and 0.1 and 0.33 atm of SiH_4 and O_2, the reaction was complete within 15 minutes. The thickness of the SiO_2 film was estimated to be about 0.1 µm. Measurements of H_2 and N_2 permeation rates showed that the SiO_2 film was highly selective to H_2 permeation. The H_2:N_2 flux at 450°C varied between 2000-3000.

Thin SiO_2 films were heat treated in different gas mixtures to determine their stability in functioning as high-temperature hydrogen-permselective membranes. The films were heat-treated at 450-700°C in dry N_2, dry O_2, N_2-H_2O, and O_2-H_2O mixtures. The permeation rates of H_2 and N_2 changed depending on the original conditions of film formation as well as on the heat treatment. Heating in dry N_2 slowly reduced the permeation rates of both H_2 and N_2. Heating in a N_2-H_2O atmosphere led to a steeper decline of H_2 permeability. But the permeation rate of N_2 increased or decreased according to whether the film deposition had been carried out in the absence or presence of H_2O vapor, respectively. Thermal treatment in O_2 caused rapid decline of the permeation rates of H_2 and N_2 in films that were deposited under dry conditions. The decline was moderate in films deposited under wet conditions.

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A presente tese de doutorado propõe-se a investigar o lúdico como um ingrediente das situações de trabalho. Tem-se como referência teórica os materiais oriundos da Ergologia e das abordagens clinicas sobre trabalho: Psicodinâmica do Trabalho e Clinica da Atividade. Os autores pesquisados concordam que independentemente de época histórica, cultura e classe social, jogar e brincar fazem parte da vida da criança, onde real e imaginário se confundem. O jogo constitui uma função tão fundamental para a humanidade quanto a razão e a fabricação de objetos. A cultura possui um caráter essencialmente lúdico; é no jogo e pelo jogo que a civilização surge e se desenvolve. O brincar é uma atividade humana universal, própria da saúde, fundamento de todo o viver criativo, assim como da arte e da cultura. O próprio homem medieval é muito sensível ao lúdico e convive a cada instante com o riso e com a brincadeira. O foco desta pesquisa foi uma aproximação à realidade do trabalho de alguns integrantes de um Programa Adolescente Trabalhador, com idade entre 14 e 18 anos. O campo empírico foi a Gerência Regional de Logística do Banco do Brasil, situada no bairro do Andaraí, no município do Rio de Janeiro. Sete adolescentes participaram da Comunidade Ampliada de Pesquisa. O trabalho de campo foi norteado pela preocupação em evitar a supremacia do saber científico em relação a saberes advindos da prática. Este trabalho de pesquisa não se propôs a pesquisar a realidade de trabalho dos menores, mas investigar os movimentos discursivos produzidos nos Encontros desta Comunidade de Pesquisa. Conforme a abordagem da Clínica da Atividade chama-se à atenção para vários impedimentos da emergência da dimensão lúdica em função dos constrangimentos da organização do trabalho. Por fim, questiona-se que modos de gestão olham para a realidade e o real do trabalho e da atividade, aceitando o lúdico como foco analítico, incorporando essa reserva de alternativa, investigando toda uma riqueza aí potencialmente presente e desconhecida.

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During the rainy season in extensive river floodplains and deltaic lowlands, floods render the land unavailable for crop production for several months each year. These waters are considerably underutilized in terms of managed aquatic productivity. This raises the opportunity to enclose parts of these floodwater areas to produce a crop of specifically stocked aquatic organisms aside from the naturally occurring ‘wild’ species that are traditionally fished and are not affected by the culture activity, resulting in more high-quality, nutrient-dense food production and enhanced farm income for all stakeholders, notably the poor. The WorldFish Center and its national partners recently tested the concurrent rice-fish culture in the shallower flooded areas and the alternating rice-fish culture in the deep-flooded areas of Bangladesh and Viet Nam through a community-based management system. Results indicate that community-based fish culture in rice fields can increase fish production by about 600 kg/ha/year in shallow flooded areas and up to 1.5 t/ha/year in deep-flooded areas, without a reduction in the rice yield or wild fish catch.

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South Africa- Shifting livelihoods, Viet Nam-Strengthening livelihoods, Chile - gains and challenges, Uganda- making changes possible, Maritza Mena from Costa Rica, Ground-breaking gender indicators, You tube resources

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Ecological study on Kolahy and 'flab estuaries were carried out during 1996-1997. Water and sediment sampling was done seasonally. In order to study the physical and chemical characteristic of the water, various animal fauna from different material niches including planktons and fish from water, benthousi from the sediment , and surface living animal such as Arthropod (Crabs) and Waterbirds were identified. I he result shoved, that water salinity of both estuaries was the same as the general salinity existing its the Persian Gulf water, and its variation is same IN those waters Minimum water salinity in both estuaries are seen during Bahairdan or early winter mooth(Jaa.), which is about 31ppt and Maximum is during .rirldlun.) or summer mouth at about 19 ppt. Dissolved otygen and pH are slime as the general Persian Gulf waters., Dissolve Oxygen being directly associated to temperature and its fluctuation is between 7- Sing/I and pH between 7.5-LS. The animals of both estuaries are almost similar having a sal factory species diversity . The birds of the region are often seasonal migrants , the maximum population of which occurs in winter season and the minimum during summer month. Nam coverage is richer in Tiab than Kolahy estuary, where in Kolahy a signal Mangrove tree is in exigence. 'Ile total coverage of Mangrove forest in Tiab is estimated about -29 hec.Both estuaries are included with in the international Ramsar Convention sites in 1971. Due to national importance of these estuaries inproviding refugee for various birds species and also hinting grounds and access traffic for local fishing vehicles, Actiog as an important access for various inhabitancy living with these area of the Persian Gulf. Due to importance or prawn aquacultur for the economical well being of local inhabitance, these areas provide a suitable grandees for prawn production. I-test statistics show, there are no significant difference among various invertebrate and vertebrate animals. In over all out look 21) phytoplankton genera, 21) zeoplankton genera 17 miafauna and 32 roaerofauna genera , 11 different species Carcineacearions and 119 species of walerbirds were identified with in the Tiab and Kolahy estuariesregioos. The X statistic show that the animal density is directly associated to season. Where density of miofauna and maerofauna in both estuaries are in maiticrourn during summer and the minimums existing during the winter season. In addition the bentic invertebrate population density in closlly association to birds population density since , the later, feeds on the former animals. Where the increasing in bird population density during the winter season, the bentic invertebrate animal population density decreases. The over all trend of animal population density in winter tend to increased towards the summer seasons, which this is due to climatic conditions of the region. The bird population on the contrary to other animals of both estuaries tend to increase from summer towards the winter seasons and which this bird population density is in maximum in winter with in the region.

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目的 检测7 种从蛇毒分离的小肽是否对临床分离的耐药性结核分枝杆菌菌株具有活性。方法 放射性方法检测蛇毒 小肽对结核分枝杆菌的最小抑制浓度,细菌存活计数确证放射性方法的结果。结果 7 种蛇毒小肽对耐药性结核分枝杆菌菌 株都有活性。其MIC 值分别为(μg·mL - 1) : Opiophagus hannah 5. 4 , Naja at ra 8. 6 , B ungarus f asciatus 6. 4 , Trimeresurus ste2 jnegri 12. 6 , Protobothrops mucrosquamatus 11. 8 , Protobothrops jerdonii 7 , A gksist rodon halys 4. 2 。结论 这些结果是首次报 道,为进一步设计和开发新来源的抗结核病新药提供了依据。

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An improved technique for transferring large area graphene grown by chemical vapor deposition on copper is presented. It is based on mechanical separation of the graphene/copper by H2 bubbles during H2O electrolysis, which only takes a few tens of seconds while leaving the copper cathode intact. A semi-rigid plastic frame in combination with thin polymer layer span on graphene gives a convenient way of handling- and avoiding wrinkles and holes in graphene. Optical and electrical characterizations prove the graphene quality is better than that obtained by traditional wet etching transfer. This technique appears to be highly reproducible and cost efficient. © 2013 American Institute of Physics.