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一、“这是世界上唯一的能每日自我更新的国家”。当今美国管理状况是良性的。我并不是属于认为美国是缺乏“竞争力”的那种人。我认为美国的管理者是构成世界上最有生气的经济的一个组成部分——我还认为美国管理者在确保经济健康发展方面是很值得称道的。今天我们是处在史无前列的经济发展的第七年头——这是一种就我所知的经典经济学家曾梦寐以求的发展。 相似文献
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管理者常常会认为员工工作良好。当然会有一两名员工表现不够好,但是员工总体上表现优良。工作差的员工在组织中待不久,因为管理者会在他们影响其他员工之前,迅速让他们离开组织。留在组织中的员工为了应得的薪水而付出相应的努力。他们可靠而有见识,值得信赖,而且没有怨言地进行工作,但是他们的业绩是否超出管理者的期望了呢?事实并非如此。 相似文献
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Akin J Guilkey D Popkin B Flieger W Briscoe J Black RE Adair LS 《Journal of development economics》1992,38(2):323-351
Collaborating researchers used a multi equation model to analyze 3080 mother-infant pairs living on the island of Cebu in the central Philippines and to estimate a child health production function. The econometric methods used eliminated obstacles such as heterogeneity and endogeneity of significant explanatory factors. They also maximized the longitudinal quality of the data. The results showed that morbidity in 1 period reduced infant weight in following periods. For example, diarrhea and febrile respiratory infection reduced growth in the time period following the illnesses. Further effects of some contributing factors were great near birth not diminished with age. For example, breast feeding promoted growth and protected against infection, especially diarrhea and febrile respiratory infection, more substantially near birth than it did later. Further, in urban areas, preventive health care positively affected growth independently of its indirect influence on reducing respiratory infection. Yet it had little effect on diarrhea. Diarrhea had a strong adverse effect on growth. Exposure of the infant to enteric pathogens had the greatest influence on production of diarrhea. In urban areas, exposure included water supply contamination, exposure to feces, a more pathogenic diet, and community crowding. In rural areas, however, exposure included community crowding and increased rainfall which presumably washed feces into the water supply. Household crowding in both urban and rural areas and irritation from smoke in urban areas only tended to bring about febrile respiratory infection. 相似文献
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Upflow anaerobic sludge bed reactors fed on glucose were used to investigate the effects of Ce(3+) on soluble microbial products (SMP) production, which is the majority of the residual chemical oxygen demand present in the effluent. It was found that Ce(3+) concentration of 0.05 mg/L had no significant effect on the amount of SMP production, whereas that of 1 mg/L led to the increase in SMP production. The molecular-weight distribution and carbohydrate analysis indicated that an increase in SMP production may be partly attributed to the release of extracellular polymeric substances (EPS) into the bulk solution resulted from cerium toxicity, and the nucleic acids analysis suggested that increased cell lysis also contributed to SMP accumulation in the presence of Ce(3+). The increase in SMP production in the presence of Ce(3+) is possibly a consequence of the release of EPS and increased cell lysis due to cerium toxicity. 相似文献
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This study aimed at enhancing knowledge on the fate of diclofenac (DF), together with its main human metabolite 4'-hydroxydiclofenac (4'OHDF), during wastewater treatment by using a laboratory-scale membrane bioreactor (MBR). The reactor was fed continuously with non-radiolabelled diclofenac for a one month period prior to a single pulse of a 14C-radiolabelled solution of DF and 4'OHDF. The solution spike contained approximately 25% 4'OHDF and 65% DF, which corresponds to the ratio observed in municipal sewage, as well as traces of two other metabolites. The radioactivity was monitored for a total of twelve days in the various output streams. The calculation of the complete mass balance in the system demonstrated that the major part of the radioactivity left the reactor with the permeate (88.7%), while 2.1% was recovered in the excess sludge. Negligible amounts were recovered in the off-gas traps and on the membranes. Chromatographic analyses of effluent samples, by means of HPLC-MS coupled in parallel to a radiodetector, displayed a different pattern than the one of the spiked solution. It showed the occurrence of three additional metabolites. 相似文献