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101.
通过对BOT投融资方式的基本知识的介绍及其在电力事几个试点项目的应用,在总结经验教训的基础上,阐述中国引进BOT项目有关问题。 相似文献
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简述经评审的最低投标价法的概念,结合实际情况,阐述经评审的最低投标价法的认识,实施及其意义,并分析了实施过程中存在的问题,提出了相应的对策,以期促进有形建筑市场健康、有序的发展。 相似文献
104.
《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2013,30(3):308-324
Contamination of grain with 1,2-dehydropyrrolizidine ester alkaloids (dehydroPAs) and their N-oxides is responsible for large incidents of acute and subacute food poisoning, with high morbidity and mortality, in Africa and in central and south Asia. Herbal medicines and teas containing dehydroPAs have also caused fatalities in both developed and developing countries. There is now increasing recognition that some staple and widely consumed foods are sometimes contaminated by dehydroPAs and their N-oxides at levels that, while insufficient to cause acute poisoning, greatly exceed maximum tolerable daily intakes and/or maximum levels determined by a number of independent risk assessment authorities. This suggests that there may have been cases of disease in the past not recognised as resulting from dietary exposure to dehydroPAs. A review of the literature shows that there are a number of reports of liver disease where either exposure to dehydroPAs was suspected but no source was identified or a dehydroPA-aetiology was not considered but the symptoms and pathology suggests their involvement. DehydroPAs also cause progressive, chronic diseases such as cancer and pulmonary arterial hypertension but proof of their involvement in human cases of these chronic diseases, including sources of exposure to dehydroPAs, has generally been lacking. Growing recognition of hazardous levels of dehydroPAs in a range of common foods suggests that physicians and clinicians need to be alert to the possibility that these contaminants may, in some cases, be a possible cause of chronic diseases such as cirrhosis, pulmonary hypertension and cancer in humans. 相似文献
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《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2013,30(2):241-248
The aim of this study was to determine the levels of Penicillium citreonigrum and citreoviridin present in rice samples from Maranhão State, Brazil, where an outbreak of beriberi was reported and 32 deaths occurred (7% of the notified cases died in 2006). The ability of P. citreonigrum to produce citreoviridin was assessed, and a total of 420 samples of 21 different kinds of rice were collected. Mycobiota isolation and identification, the ability of citreoviridin strains to produce toxin, and the natural occurrence of citreoviridin were established. Rice samples were found to have high fungal counts and showed increasing levels from 2004 to 2007 harvest years. The most frequent genus was Aspergillus followed by Penicillium and Cladosporium. Ten out of eleven strains of P. citreonigrum were able to produce citreoviridin. Three rice samples had levels of citreoviridin ranging from 12 to 96.7 ng g?1, and two bran samples had levels of 128 and 254 ng g?1. These samples contaminated with P. citreonigrum and citreoviridin were involved in the beriberi cases from Maranhão State. Monitoring rice for mycotoxins in areas where this substrate is the basic food is crucial to prevent outbreaks like the one reported in this study, to improve management practice, and to diminish exposure risk of humans to these harmful toxins. 相似文献
106.
唐朝继 《湖南纺织高等专科学校学报》2010,(2):106-109
我国高校实行的是党委领导下的校长负责制,校务公开已深入人心。在新的历史时期,认真研究高校基层党组织的党务公开工作,对于促进高校的科学党建,作用重大,意义深远。就高校党务公开的重要意义、党务公开的路径选择、党务公开实效性的基准坐标等三个层面进行探析,为高校党建工作者做好党务公开工作提供借鉴。 相似文献
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Does task significance increase job performance? Correlational designs and confounded manipulations have prevented researchers from assessing the causal impact of task significance on job performance. To address this gap, 3 field experiments examined the performance effects, relational mechanisms, and boundary conditions of task significance. In Experiment 1, fundraising callers who received a task significance intervention increased their levels of job performance relative to callers in 2 other conditions and to their own prior performance. In Experiment 2, task significance increased the job dedication and helping behavior of lifeguards, and these effects were mediated by increases in perceptions of social impact and social worth. In Experiment 3, conscientiousness and prosocial values moderated the effects of task significance on the performance of new fundraising callers. The results provide fresh insights into the effects, relational mechanisms, and boundary conditions of task significance, offering noteworthy implications for theory, research, and practice on job design, social information processing, and work motivation and performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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