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121.
Several writers on animal ethics defend the abolition of most or all animal agriculture, which they consider an unethical exploitation of sentient non-human animals. However, animal agriculture can also be seen as a co-evolution over thousands of years, that has affected biology and behavior on the one hand, and quality of life of humans and domestic animals on the other. Furthermore, animals are important in sustainable agriculture. They can increase efficiency by their ability to transform materials unsuitable for human consumption and by grazing areas that would be difficult to harvest otherwise. Grazing of natural pastures is essential for the pastoral landscape, an important habitat for wild flora and fauna and much valued by humans for its aesthetic value. Thus it seems that the environment gains substantially when animals are included in sustainable agricultural systems. But what about the animals themselves? Objections against animal agriculture often refer to the disrespect for animals’ lives, integrity, and welfare in present intensive animal production systems. Of the three issues at stake, neither integrity nor animal welfare need in principle be violated in carefully designed animal husbandry systems. The main ethical conflict seems to lie in the killing of animals, which is inevitable if the system is to deliver animal products. In this paper, we present the benefits and costs to humans and animals of including animals in sustainable agriculture, and discuss how to address some of the ethical issues involved.  相似文献   
122.
Management by objectives (MBO) is a technique for integrating ecological concerns into national political and administrative structures. Politicians determine environmental objectives and interim targets to be implemented and assessed by civil servants in national, regional, and local contexts. Well-developed organizational communication is a prerequisite for MBO. However, communication-related obstacles can arise when using MBO in public environmental management. We examine communicative aspects of environmental MBO, looking specifically at the implementation, administration, and assessment of Swedish environmental quality objectives. Our argument is illustrated by quotations from individual and focus group interviews. We conclude that communicative problems may arise, because different actors interpret messages from different perspectives, depending on their agendas, prior knowledge and experience, and positions in the administrative system. It is crucial to recognize the dialogical aspects of communication, by involving the receiver of a message in a process of response. In addition, the different timeframes underlying different arguments could contribute to misunderstandings between actors involved in handling environmental issues. In assessing the achievement of environmental objectives, indicators are used as communicative tools. It is important to investigate whether and how these indicators contribute to the de- and recontextualization of environmental objectives.  相似文献   
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The effects of NiCl2 were studied in two human cell lines, HeLa and diploid embryonic fibroblasts as well as in V79 Chinese hamster cells and in L‐A mouse fibroblasts. NiCl2 produces a dose‐dependent depression of proliferation, mitotic rate, and viability, accompanied by an increasing release of lactic dehydrogenase and stimulation of lactic acid production. The plating efficiency is reduced, as are DNA and protein synthesis and, to a lesser degree, RNA synthesis.

The cytotoxicity of NiCl2 is comparable in degree to those of PbCl2 and MnCl2, but is weaker than those of HgCl2 and CdCl2. However, the different sensitivities of different cell lines must also be considered.

NiCl2 effects are more severe in serum‐free medium than in medium containing serum or serum albumin indicating that serum constituents, notably albumin, bind the metal effectively and inhibit cellular uptake; this confirms earlier reports on the serum binding and slow uptake of NiCl2.

Synchronized cells are most sensitive in the Gl and early S phases of the cell cycle. In the Painter test the depression of DNA synthesis persists following cessation of exposure to NiCI2. These findings contribute an explanation for the known genotoxic effects of nickel.  相似文献   
125.
We report a series of 350 patients submitted to transabdominal chorionic villus sampling (CVS). A technique using two ultrasound-guided needles and a suction pump was used. In most cases, the procedure was performed between 9 and 13 weeks. Twenty-one pregnancies were selectively terminated; nine spontaneous abortions followed the procedure and one fetal loss after 28 weeks was recorded; 153 pregnancies are in progress and 169 delivered fetuses are alive and well. Transabdominal biopsy is a feasible and effective technique for CVS.  相似文献   
126.
The starting point for this article is the need to develop empirical insights about contemporary societal risk and safety management practice and executive structures. In order to facilitate insights about societal risk and safety management in a Scandinavian welfare context we use Sweden and its local governmental level (municipal) as an empirical frame in this paper. The aim for this article is to analyse how a variety of risk and safety management tasks are divided within the Swedish municipalities. The objectives are to frame the current directions for internal allocations of risk and safety issues by providing an empirically based executive typology and to contemplate the implications and future research needs that arise from that management pattern.The analysis is based on statistical analysis of information from a web-survey with chief officials (n = 1283) with responsibilities for different municipal functions and sectors. In this study the responses to one of the survey questions are used for statistical analysis. The analyzed question focused on the degree that the respondents estimated that their administrative sector or function handled a selection of risk and safety management assignments (n = 45). A factor analysis was applied to identify patterns in the dataset. The analysis resulted in an eight factor solution with a high degree of explained variance (74.3%). The results provide an elementary contribution to the understanding of the current societal risks and safety management directions.  相似文献   
127.
Total concentrations of Cd, Cr, Fe, Ni, Pb and Zn were compared from October 1996 to April 1998 in Physcia biziana (Massal.) Zhalbr. v. leptophylla Vezda and in the bark of Quercus ilex L. sampled from the same trees at an urban park. Trace metal concentrations were also measured in the bark covered by the lichen thalli. The lichens showed significantly higher Cr, Fe, Ni and Zn concentrations than both uncovered and covered barks. By contrast, both types of barks had higher concentrations of Cd and Pb than lichens. Trace elements showed a wide temporal variation of concentrations both in the lichens and barks. No relationship was found between the analysed matrices as regards the time course of trace element concentrations.  相似文献   
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Among the wide range of compounds reaching the soil are the veterinary antimicrobials. Since no regulations regarding acceptable levels of drug concentrations in the environment exist, monitoring tests, particularly concerning soils, are carried out very rarely. This study presents a preliminary assessment of the contamination of agricultural soils in Northern Poland with seven antimicrobial veterinary medicines which has never been carried out before. Veterinary drugs were detected in 54% of the examined soil samples; the most commonly detected drugs were sulfonamides and trimethoprim. The highest indicated concentrations refer to enrofloxacin (57.0 μg kg?1) and trimethoprim (47.8 μg kg?1). The presence of these target drugs in the soil environment confirms the need for further monitoring studies. The analytical methods developed in this study are an excellent tool to achieve this goal and allow an estimation of the risk connected with the presence of veterinary antimicrobials in soils.

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130.
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