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Thirty spring wheat varieties were evaluated and classified into eight different groups on the basis of their grain yield performance and phosphorus (P) uptake using Metroglyph analysis. Significant variability was observed for grain and biomass yield, plant height, P content in grain and straw, total P uptake and phosphorus harvest index and P use efficiency traits. Varieties WH 711 and PBW 343 exhibited high grain yield as well as high P uptake (HGY-HP). WH 283 and UP 2425 with high index score of 19 and 16 respectively, constituted the high grain yield-medium P uptake (HGYMP) group. Both these varieties, though had similar grain yield of 5348 kg/ha, but WH 283 (12.64 kg/ha) utilized much lower P as compared to UP 2425 (16.94 kg/ha). Moreover, WH 283 (81.64) also showed higher values for phosphorus harvest index (PHI) than UP 2425 (67.88%). P uptake of WH 283 was comparable with that of Raj 3765 (10.78 kg/ha) and grouped into high grain yield and low P uptake (HGY-LP) group. The grain yield performance of these two varieties with a relatively low P uptake is reflected in their high index score for P use efficiency thus, earmarking them for low P regimes. Variety HW 2006, despite low grain yields of 4665 kg/ha had high index score of 16 due to its higher value for Phosphorus Biological (PBER) and Economic Yield (PEER) Efficiency Ratio as it has effected least (7.18 kg/ha) P mobilization. In addition high P translocation in the grain was also observed for this variety. Inter-mating of genotypes like HW 2006, UP 2338 and HW 2016 with those belonging to HGY-HP (PBW 343 and WH 711) and HGY-LP (Raj 3765 and WH 283) would be an ideal strategy to develop the cultivars for efficient phosphorus use.  相似文献   
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A large number of related compounds, all based on the prototype parent compound thiabendazole are now available on the market, each one claiming distinct advantages and applications for anti-parasitic use. The ever increasing number of benzimidazoles appearing regularly is a good example of so called molecular manipulation of molecular roulette whereby individual pharmaceutical companies endeavour to compete with a rival company's successful product without breaching the patent rights of a particular compound.  相似文献   
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Many candidate antigens of malaria vaccines have limited immunological recognition. One exception is Pfs25, a cysteine-rich, 25-kilodalton sexual stage surface protein of Plasmodium falciparum. Pfs25 is a target of monoclonal antibodies that block transmission of malaria from vertebrate host to mosquito vector. The surface of mammalian cells infected with a recombinant vaccinia virus that expressed Pfs25 specifically bound transmission-blocking monoclonal antibodies. Furthermore, major histocompatibility complex-disparate congenic mouse strains immunized with recombinant Pfs25 elicited transmission-blocking antibodies, demonstrating that the capacity to develop transmission-blocking antibodies is not genetically restricted in mice. Live recombinant viruses may provide an inexpensive, easily administered alternative to subunit vaccines prepared from purified recombinant proteins to block transmission of malaria in developing countries.  相似文献   
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Growing supermarket dominance and the expansion of own-label market share in Australia has put considerable pressure on agri-food manufacturers, and the recent movement of a number of manufacturing operations off-shore has attracted widespread attention. This paper examines the pursuit of an international manufacturing base by SPC Ardmona, one of Australia’s major fruit and vegetable processors, with a focus on strategic alliances formed with Siam Foods in Thailand and Rhodes Food Group in South Africa/Swaziland. Strategic horizontal alliances have become increasingly important for manufacturers seeking to counter retailer dominance, yet have received little attention in the agri-food literature. The two alliances examined in this paper illustrate the profound importance of prevailing societal and institutional environments in which production networks ‘touch-down’, and their influence on firm-level dynamics of trust, motivation, corporate values, and strategic objectives. Horizontal alliances can offer a promising alternative to cut-throat competition and a ‘race- to-the-bottom’ between agri-food manufacturers. However, with own-label sourcing strategies deepening competition between geographically-disparate manufacturers, identifying compatible alliance partners is likely to become an increasingly greater challenge.  相似文献   
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Kentucky farmers and University of Kentucky extension agents applied the principles of the Work Crew Performance Model (WCPM), used previously in mining and construction, to identify and prioritize critical action factors (CAFs) for safe handling of cattle. One focus group of farmers helped identify a set of 32 critical action factors in four categories: environmental conditions, animal behavior, facilities and equipment, and handling techniques. A second focus group of farmers used a Q-sort nominal group process to rate each of the factors on the basis of the cost consequences of failure to properly perform the activity. A three-stage binary sort process resulted in a five-point ordinal ranking of tasks within each of the four categories. The Q-sort procedure was performed with assumptions of both routine and emergency animal handling activities. The list and the rankings were validated and modified by extension agriculture agents and by an expert panel of animal scientists and an agricultural engineering educator. The validation process added seven CAFs to the original list. The result of the process was the development of a cattle safety handling checklist that has been used with success in Master Cattleman educational workshops conducted for approximately 1500 Kentucky farmers.  相似文献   
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