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51.
在中国南部的广东省,正在兴起一种家具制造的新模式:通过签订协议,按照顾客的个性化需求对家具进行量身定制。2011年中期,劳卡公司投资建立了一家新工厂,该厂生产面积约1万m^2。通过实践,根据舒乐咨询公司建议的组织结构,在同等工作量投入的情况下,中国工人的人均产量却增长了近4倍。与之前封边机封边数量为每天1 800次相比,现在封边机每天可以完成3 400次的封边。  相似文献   
52.
  1. Global environmental change is threatening freshwater biodiversity with ecological impacts predicted to be particularly severe in high-altitude regions. Despite this, an ecological understanding of high-altitude pond networks remains patchy, with only limited knowledge of the environmental and spatial predictors of taxonomic and functional diversity. Moreover, previous studies of pond ecosystems have focused primarily on taxonomic richness and largely overlooked functional diversity.
  2. This study examined the influence of local environmental and spatial factors on taxonomic and functional α and β diversity (including the turnover and nestedness-resultant components) of 17 high-altitude (~2,500 m above sea level) pond macroinvertebrate communities, in the Macun Cirque, Switzerland.
  3. Spatial processes (pond connectivity) were important drivers for taxonomic α diversity, while local environmental variables (pond permanence and surface area) were important determinants of functional α diversity. Species turnover was the most important component of β diversity for taxonomic composition, and functional composition demonstrated a nested spatial pattern.
  4. Variation in taxonomic and functional composition (and the turnover and nestedness components of β diversity) were determined by local environmental variables despite the limited environmental gradients within the pond network. No significant effects of spatial variables on community composition were recorded for either facet of diversity, indicating that compositional variation was determined at a local scale. Water temperature, depth and pond permanence were consistently the most important measured drivers of diversity.
  5. Given the importance of both spatial and environmental variables in structuring taxonomic and functional diversity, landscape-scale conservation and management activities that aim to improve or protect high-altitude freshwater biodiversity should focus on maintaining connectivity among ponds and environmental heterogeneity, particularly pond surface area, water depth, and hydroperiod. Understanding the mechanisms driving taxonomic and functional diversity will be critically important for the management and conservation of macroinvertebrate communities in high-altitude pond networks in the face of climatic warming.
  相似文献   
53.
The grey squirrel is recognised as a pest species of economic importance but the justification of the view appears to be founded on local areas of severe damage. Despite evidence that damage may not be alleviated by squirrel population destruction, Warfarin poisoning was introduced as an alternative to trapping.The utilisation by wildlife of a poison hopper designed for grey squirrel control was investigated by automatic photography. Results confirmed that a number of species may feed from the grain presented via the hopper. However, the majority of the bait was removed during the hours of darkness when grey squirrels were not active. It is a conservative estimate that between 55 and 65% of the grain entered the environment via animals other than squirrels.In addition, the removalof bait by night visitors resulted in the accumulation of large quantities of bait at and around the entrance to the hopper tunnel. This increased accessibility to the potentially poisoned bait by animals other than squirrels.Until such time as evidence is produced to show these results as exceptional, it can only be concluded that fears expressed over the lack of specificity of this method of control are justified.  相似文献   
54.
开放性是互联网最根本的特性,互联网的开放性不仅仅是技术层面上的,它还有更深的内涵。在过去的15年,随着覆盖面越来越大,互联网的增长速度不断加快,互联网意义越来越重大。互联网的开放标准使得“互连”更加便宜和便捷,消融了学术之间、企业之间以及消费者网络之间的界限。正如国家之间的自由贸易协定增加了市场规模、扩大了收益,互联网...  相似文献   
55.
56.
Two groups of 10 pregnant cows were inoculated with bluetongue virus type 11 at either 40 or 60 days of gestation. All the cows became infected as judged by the detection of viraemia and seroconversion but they showed no clinical signs. Seventeen of the cows produced live calves none of which showed any evidence of prenatal infection. After challenge with the same virus all the calves became viraemic and seroconverted. The response to challenge of the two groups did not differ from that of a control group challenged at the same time. It was concluded that the infection of pregnant cows in early gestation with this virus did not result in the transplacental infection of the fetuses and did not produce immunotolerant, latently infected calves.  相似文献   
57.
Breeding value estimation procedures for two traits with moderate and high heritability were evaluated by using a single-trait animal model and computer-simulated data designs. Of interest were the effects of differing numbers of animals and degrees of relationships among animals within and across contemporary groups (tests). Test effects were assumed fixed and animal effects were assumed random. Family size, number of families per contemporary group, and degree of genetic relationships within and across contemporary groups were varied to determine interrelationships among the factors. Results were compared on the basis of accuracy by using both the correlation of true and estimated breeding values and the prediction error variance obtained from the inverse of the coefficient matrix of the mixed-model equations. Small contemporary groups in conjunction with evaluation of closely related families caused average accuracy to decrease relative to that obtained with the same number of unrelated animals because genetically related animals were less accurately evaluated relative to one another. Connecting contemporary groups with a genetic relationship matrix formed a large set of interdependent equations and improved the average accuracy of predicted breeding values. The slight decrease in accuracy for genetically related animals was more than offset by the increase in accuracy of evaluation for their unrelated test mates because the proportion of fixed effects to random effects was smaller. Care must be exercised in designing evaluation schemes involving small populations, and the decision of which fixed effects to include in the model is critical.  相似文献   
58.
A colloidal dispersion formulation of 9‐aminocamptothecin (9‐AC) was administered intravenously to 10 dogs with previously untreated, spontaneously occurring, multicentric lymphoma. The dogs received a 72‐h infusion of 9‐AC at a rate of 46.5–51.25 µg m?2 h?1 (total dose range 3.35–3.69 mg m?2). This dose range was associated with myelosuppression, consisting principally of neutropenia with a nadir at 7 days following the start of infusion. Neutropenia and thrombocytopenia were the most common toxicoses and are most likely to be dose‐limiting toxicities; low‐grade gastrointestinal signs were rarely seen. Concentrations of 9‐AC lactone, as well as clinical toxicities, compare favourably with those found in humans. Tumour responses were seen in all treated dogs. Response to other chemotherapy, following cessation of 9‐AC treatment, was not obviously compromised even in dogs clinically resistant to 9‐AC. 9‐AC is a novel treatment drug for canine lymphoma, which appears to show great promise.  相似文献   
59.
Nine stable hybridoma cell lines were established which secreted specific monoclonal antibodies (MAbs) to bovine gamma-interferon (BoIFN-gamma). Specific binding of each of the MAbs to recombinant BoIFN-gamma (rBoIFN-gamma) was demonstrated in an indirect ELISA, whilst none of the MAbs bound to rBoIFN-alpha or rBoIFN-beta. In a Western blot the MAbs reacted with the 16 kDa and 32 kDa polypeptides present in rBoIFN-gamma preparations. Competitive ELISA's showed that four MAbs bound to one epitope on rBoIFN-gamma, and the other five MAbs bound to a separate epitope. Two MAbs, each recognising different epitopes, were shown to neutralise the anti-viral activity of natural BoIFN-gamma.  相似文献   
60.
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