864 resultados para requirements for selling


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BACKGROUND: HIV-1 Vpu targets newly synthesized CD4 receptor for rapid degradation by a process reminiscent of endoplasmic reticulum (ER)-associated protein degradation (ERAD). Vpu is thought to act as an adaptor protein, connecting CD4 to the ubiquitin (Ub)-proteasome degradative system through an interaction with beta-TrCP, a component of the SCFbeta-TrCP E3 Ub ligase complex. RESULTS: Here, we provide direct evidence indicating that Vpu promotes trans-ubiquitination of CD4 through recruitment of SCFbeta-TrCP in human cells. To examine whether Ub conjugation occurs on the cytosolic tail of CD4, we substituted all four Ub acceptor lysine residues for arginines. Replacement of cytosolic lysine residues reduced but did not prevent Vpu-mediated CD4 degradation and ubiquitination, suggesting that Vpu-mediated CD4 degradation is not entirely dependent on the ubiquitination of cytosolic lysines and as such might also involve ubiquitination of other sites. Cell fractionation studies revealed that Vpu enhanced the levels of ubiquitinated forms of CD4 detected in association with not only the ER membrane but also the cytosol. Interestingly, significant amounts of membrane-associated ubiquitinated CD4 appeared to be fully dislocated since they could be recovered following sodium carbonate salt treatment. Finally, expression of a transdominant negative mutant of the AAA ATPase Cdc48/p97 involved in the extraction of ERAD substrates from the ER membrane inhibited Vpu-mediated CD4 degradation. CONCLUSION: Taken together, these results are consistent with a model whereby HIV-1 Vpu targets CD4 for degradation by an ERAD-like process involving most likely poly-ubiquitination of the CD4 cytosolic tail by SCFbeta-TrCP prior to dislocation of receptor molecules across the ER membrane by a process that depends on the AAA ATPase Cdc48/p97.

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Face aux données conflictuelles de la littérature sur le VO2 requis d’exercices de boxe (sparring, palettes de frappe et sac de frappe), surtout pour le “vrai” sparring avec coups de poings au visage, une nouvelle méthode basée sur une mesure de VO2 “post-exercice” fut développée, validée (Annexe 1) et utilisée pour ré-évaluer le coût énergétique de ces exercices de boxe. Neufs boxeurs mâles expérimentés, de 22.0±3.5 ans et 71.4±10.9 kg avec un VO2pic de 62.2±4.1 ml·kg-1·min-1 (moyenne ± écart type) furent mesurés lors 1) d’un test progressif maximal sur tapis roulant en laboratoire 2) d’un entrainement standardisé de boxe en gymnase et 3) d’exercices de boxe standardisés en laboratoire. Des VO2 requis de 43.4±5.9, 41.1±5.1, 24.7±6.1, 30.4±5.8 et 38.3±6.5 ml·kg-1·min-1, respectivement obtenues pour le sparring, les palettes de frappe et le sac de frappe à 60, 120 et 180 coup·min-1, situe l’intensité de ces exercices autour de ~70 %VO2pic.

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In many European countries, one of the most complex and widely discussed issues addressed by legal systems with respect to forced selling of limited liability and public limited company shares is the impact of possible statutory restrictions on transfers . Thus, while some authors deny the applicability of such provisions (as a possible avenue for commission of creditor fraud) , others support their validity (on the basis of prevention of possible fraudulent actions affecting interests protected by restrictive causes). In my opinion, a solution must be found in which prosecution of creditor fraud co-exists with respect for the rights scheme. As a general rule, this solution would call for applicability of restrictive clauses to cases of forced selling, regardless of whether such statutory provisions are viewed in terms of order or alienation.

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School of Management Studies, Cochin University of Science and Technology

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Man in his quest to explore food has turned towards the oceans and during the last five decades there has been phenomenal increase in the exploitation of the marine fisheries resources. The present study is carried out to determine the requirement of protein and water-soluble vitamins in the diet of juveniles of the Indian white prawn p.indicus using purified diets and to evaluate the nutritive value of a few plant and animal protein sources for the same species. A total of ten statistically designed experiments are conducted in the laboratory undermost identical conditions and following similar methodologies. The study also tries to suggest the essential and optimal requirements for protein as well as water-soluble vitamins in the diet of juvenile p.indicus

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Most tropical aquatic environments are naturally fertile and their natural fertility is renewed very rapidly. Natural food for many cultivable organisms can be grown to the maximum by proper management. However, enrichment of the environment can be done through rational fertilization. Still further increase in stocking rates, can yield increased crop if adequate feeding is done. Thus fish and shellfish nutrition is an important aspect of the multidisciplinary subject of aquaculture. The oldest and most classical studies in physiology have investigated the nutritional needs of the species of interest to aquaculture. The alimentary requirements for proteins, lipids, mineral salts and vitamins have been established for some temperate species. But, the nutritional requirements of only few tropical species have been studied. Before formulating a diet, a thorough knowledge of the nutrient requirement of the species is essential. It is against this background that the present area of investigation has been identified. "Nutritional requirements of the fry of gold-spot mullet Liza parsia" is a comprehensive attempt to quantify the nutritional factors that are essential for producing healthy fingerlings for stocking the farms. Aspects such as the protein and lipid requirements of the fry, the vitamin essentiality, nutritive evaluation of protein and lipid sources suitable for compounding diets were covered in this research project. The ultimate aim has been to evolve practical diets which could be applied in the nursery phase for juvenile production.

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In India, directed research on penaeid prawn nutrition was taken up only recently when the aquaculture of prawns gained momentum. One of the important penaeid prawns sought for culture and has great potential is Penagus indiggs, H.Milne Edwards. The Central Marine Fisheries Research Institute working on different aspects of culture of this species over the past one and half decades, has developed a hatchery technology for mass production of its seed and has suggested several improvements on its farming in the grow-out systems. One of the areas of active research in this direction has been on the nutrition of the species with a view to develop suitable feed not only for hatchery production of seed, but also in the field culture. As part of this investigation, the present study, on the evaluation of different protein and carbohydrate sources and mineral requirements for the juvenile E, indicus was taken up and the results obtained are embodied in the thesis

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The optimum growth requirements of two nitrifying consortia developed from treated sewage by enrichment technique were determined by a series of experiments. There was total inhibition of nitrification at above 2.75 g r' NH/- Nand 2.5g r' N02' - N and the ammonia oxidizing consortium preferred a pH at 8.5 and the nitrite oxidizing consortium a pH of 7.5 as the optima for nitrification. Optimum temperatures were between 20° and 30°C for both the groups. As the rate of airnow was increased from I to 7 Ilmin, the build-up of N02- -N increased 10-fold and the consumption of N02- -N increased by a factor of 28.8 implying that the ammonia oxidizing consortium in a bioreactor required three times more aeration than that for nitrite oxidizers for ex pressing their full nitrifying potential. These data directly contribute for developing a fermentati on process for the mass production of nitrifiers as well as for designing bio reactors for nitrifying sewage.

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Urban and peri-urban agriculture (UPA) increasingly supplies food and non-food values to the rapidly growing West African cities. However, little is known about the resource use efficiencies in West African small-scale UPA crop and livestock production systems, and about the benefits that urban producers and retailers obtain from the cultivation and sale of UPA products. To contribute to filling this gap of knowledge, the studies comprising this doctoral thesis determined nutrient use efficiencies in representative urban crop and livestock production system in Niamey, Niger, and investigated potential health risks for consumers. Also assessed was the economic efficiency of urban farming activities. The field study, which was conducted during November 2005 to January 2008, quantified management-related horizontal nutrient flows in 10 vegetable gardens, 9 millet fields and 13 cattle and small ruminant production units. These farms, selected on the basis of a preceding study, represented the diversity of UPA crop and livestock production systems in Niamey. Based on the management intensity, the market orientation and especially the nutrient input to individual gardens and fields, these were categorized as high or low input systems. In the livestock study, high and low input cattle and small ruminant units were differentiated based on the amounts of total feed dry matter offered daily to the animals at the homestead. Additionally, economic returns to gardeners and market retailers cultivating and selling amaranth, lettuce, cabbage and tomato - four highly appreciated vegetables in Niamey were determined during a 6-months survey in forty gardens and five markets. For vegetable gardens and millet fields, significant differences in partial horizontal nutrient balances were determined for both management intensities. Per hectare, average annual partial balances for carbon (C), nitrogen (N), phosphorus (P) and potassium (K) amounted to 9936 kg C, 1133 kg N, 223 kg P and 312 kg K in high input vegetable gardens as opposed to 9580 kg C, 290 kg N, 125 kg P and 351 kg K in low input gardens. These surpluses were mainly explained by heavy use of mineral fertilizers and animal manure to which irrigation with nutrient rich wastewater added. In high input millet fields, annual surpluses of 259 kg C ha-1, 126 kg N ha-1, 20 kg P ha-1 and 0.4 kg K ha-1 were determined. Surpluses of 12 kg C ha-1, 17 kg N ha-1, and deficits of -3 kg P ha-1 and -3 kg K ha-1 were determined for low input millet fields. Here, carbon and nutrient inputs predominantly originated from livestock manure application through corralling of sheep, goats and cattle. In the livestock enterprises, N, P and K supplied by forages offered at the farm exceeded the animals’ requirements for maintenance and growth in high and low input sheep/goat as well as cattle units. The highest average growth rate determined in high input sheep/goat units was 104 g d-1 during the cool dry season, while a maximum average gain of 70 g d-1 was determined for low input sheep/goat units during the hot dry season. In low as well as in high input cattle units, animals lost weight during the hot dry season, and gained weight during the cool dry season. In all livestock units, conversion efficiencies for feeds offered at the homestead were rather poor, ranging from 13 to 42 kg dry matter (DM) per kg live weight gain (LWG) in cattle and from 16 to 43 kg DM kg-1 LWG in sheep/goats, pointing to a substantial waste of feeds and nutrients. The economic assessment of the production of four high value vegetables pointed to a low efficiency of N and P use in amaranth and lettuce production, causing low economic returns for these crops compared to tomato and cabbage to which inexpensive animal manure was applied. The net profit of market retailers depended on the type of vegetable marketed. In addition it depended on marketplace for amaranth and lettuce, and on season and marketplace for cabbage and tomato. Analysis of faecal pathogens in lettuce irrigated with river water and fertilized with animal manure indicated a substantial contamination by Salmonella spp. with 7.2 x 104 colony forming units (CFU) per 25 g of produce fresh matter, while counts of Escherichia coli averaged 3.9 x 104 CFU g-1. In lettuce irrigated with wastewater, Salmonella counts averaged 9.8 x 104 CFU 25 g-1 and E. coli counts were 0.6 x 104 CFU g-1; these values exceeded the tolerable contamination levels in vegetables of 10 CFU g-1 for E. coli and of 0 CFU 25 g-1 for Salmonella. Taken together, the results of this study indicate that Niamey’s UPA enterprises put environmental safety at risk since excess inputs of N, P and K to crop and livestock production units favour N volatilisation and groundwater pollution by nutrient leaching. However, more detailed studies are needed to corroborate these indications. Farmers’ revenues could be significantly increased if nutrient use efficiency in the different production (sub)systems was improved by better matching nutrient supply through fertilizers and feeds with the actual nutrient demands of plants and animals.

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Cassava (Manihot esculenta) is one of the most important export crops in Thailand, yet the nitrogen requirement is unknown and not considered by growers and producers. Cassava requirements for N were determined in field experiments during a period of four years and four sites on the Satuk (Suk), Don Chedi (Dc), Pak Chong (Pc),and Ban Beung (BBg) soil series in Lopburi, Supanburi, Nakhon Ratchasima, and Chonburi sites, respectively. The fertilizer treatment structure comprised 0, 62.5, 125, 187.5, 250 and 312.5 kg N ha^(-1) as urea. At each site cassava was harvested at nine months and yield parameters and the minimum datasets were taken. The fertilizer rate which resulted in maximum yield ranged from 187.5 kg N ha^(-1) in Supanburi and Chonburi (fresh weight yield of 47,500 and 30,000 kg ha^(-1) respectively) to 250 kg N ha^(-1) in Lopburi and Nakhon Ratchasima (fresh weight yield of 64,100 and 46,700 kg ha^(-1) respectively). Yield appeared to decrease at the higher, 312 kg ha^(-1), at Supanburi and Lopburi, and 250 kg ha^(-1) (Chonburi) fertilizer N rates. Net revenue was 70.4 and 72.9 % higher than where no N was appliedLopburi and Nakhon Ratchasima sites. Net revenue at the Supanburi and Chonburi sites were 53.8 and 211.0 % higher than that where no N was applied. This study suggests that at all sites improved cassava production and net revenue could be obtained with the judicious application of higher quantities of N. The results provide needed guidance to nitrogen fertilization of the important industrial crop cassava in Thailand.

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This paper proposes three tests to determine whether a given nonlinear device noise model is in agreement with accepted thermodynamic principles. These tests are applied to several models. One conclusion is that every Gaussian noise model for any nonlinear device predicts thermodynamically impossible circuit behavior: these models should be abandoned. But the nonlinear shot-noise model predicts thermodynamically acceptable behavior under a constraint derived here. Further, this constraint specifies the current noise amplitude at each operating point from knowledge of the device v - i curve alone. For the Gaussian and shot-noise models, this paper shows how the thermodynamic requirements can be reduced to concise mathematical tests involving no approximatio

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We propose a charging scheme for cost distribution along a multicast tree when cost is the responsibility of the receivers. This scheme focuses on QoS considerations and it does not depend on any specific type of service. The scheme has been designed to be used as a bridge between unicast and multicast services, solving the problem of charging multicast services by means of unicast charging and existing QoS routing mechanisms. We also include a numerical comparison and discussions of the case of non-numerical or relative QoS and on the application to some service examples in order to give a better understanding of the proposal