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志愿协议(VAs)正在作为环境政策的一种新手段出现,因为它们有超过传统政策措施的优势.具体地说,它们是经济上效率更高的.德国工业界涉及众多工业协会、大概是世界上最昂贵的1996年志愿气候保护协议,是以到2005年显著削减CO2为目标的.这项志愿协议的实施是由一个独立机构按年度监测的.从全球来说,志愿协议应当与联合实施和排放交易相互联系,从而使国际气候保护政策更加灵活和成本有效.  相似文献   
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Over the last years, the obviously increasing, hormone-dependent impairments observed in humans and animals, as well as the increased occurrence of hormone-dependent types of cancer, are sometimes associated with environmental chemicals which are suspected to imitate or block the effects of natural hormones. For a variety of environmental chemicals an endocrine efficacy could already be demonstrated. Little is known, however, about a possible hormonal activity of plant protection agents which are at present certificated in the Federal Republic of Germany. The aim of the present study was the in vitro testing of at least 57 active ingredients of pesticides and growth regulators certificated in the Federal Republic of Germany, for their possible estrogenic activity. The E-Screen-Assay based on the human breast cancer cell line MCF-7 was used as the suitable test system. For at least 8 of the tested substances, an receptor-mediated estrogenic activity could be shown in vitro. With the exception of one substance, 7 active ingredients displayed a very weak affinity for the human estrogen receptor. Their ability to displace 17β-estradiol from the receptor was low. Only the herbicide Pendimethalin is to be classified as a full estrogen receptor agonist; it is able to displace 17β-estradiol almost completely from the receptor. Howeverm the estrogenic potency of Pendimethalin, in comparison to 17β-estradiol, was seen to be as small as the estrogenic potency of the other 7 substances tested positively in the E-Screen-Assay. Among this 7 substances, two could not be classified as estrogenically active anymore, because their affinity to the human estrogen receptor was too weak. The relevance of the available results for livng organisms should be clarified in further in vivo investigations.  相似文献   
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The authors introduce the concept of leader‐signaled knowledge hiding (LSKH) and conduct two studies observing what happens when leaders signal employees that knowledge hiding (KH) is practiced, tolerated, and expected. Social learning theory provides the basis for predicting that LSKH encourages subordinates to hide knowledge, even though they suffer from negative job attitudes in reaction. In Study 1, data measured at two time points (N = 1,162) shows that LSKH positively predicts KH among subordinates. The KH dimensions of evasive hiding and playing dumb (but not rationalized hiding) negatively relate to job satisfaction and positively affect turnover intentions. Study 2 (N = 1,169) replicates these results with cross‐sectional data. Moreover, Study 2 demonstrates that evasive hiding and playing dumb negatively affect empowerment, whereas rationalized hiding has a positive effect. Both studies reveal that subordinates will show less KH when they work under leaders who avoid LSKH and in turn have more job satisfaction, feel more empowered, and harbor fewer turnover intentions. The results in this study provide important practical implications for knowledge management activities.  相似文献   
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This paper identifies the literature that deals with adaptation to climate change in the transport sector. It presents a systematic review of the adaptations suggested in the literature. Although it is frequently claimed that this socially and economically important sector is particularly vulnerable to climate change, there is comparatively little research into its adaptation. The 63 sources we found are analysed following an action framework of adaptation. This distinguishes different adaptational functions and means of adaptation. By an open coding procedure, a total of 245 adaptations are found and classified. The paper shows a broad diversity of interdependent actors to be relevant—ranging from transportation providers to public and private actors and households. Crucial actors are hybrid in terms of being public or private. A substantial share of the identified adaptations follows a top-down adaptation policy pattern where a public or hybrid operator initiates action that affects private actors. Most of the exceptions from this pattern are technical or engineering measures. Identified adaptations mostly require institutional means, followed by technical means, and knowledge. Generally, knowledge on adapting transport to climate change is still in a stage of infancy. The existing literature either focuses on overly general adaptations, or on detailed technical measures. Further research is needed on the actual implementation of adaptation, and on more precise institutional instruments that fill the gap between too vague and too site-specific adaptations.  相似文献   
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