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231.
L-Cysteine has protective efficacy in cases of oxidative tissue injury. Sodium valproate is widely used as an anticonvulsant and an antidepressant in spite of hepatotoxicity as side effect. The aim of this study was to evaluate the protective role of L-cysteine in liver toxicity induced by sodium valproate overdose. Release of the hepatic enzymes, aspartate aminotransferase and alanine aminotransferase, and levels of lipid profiles, as well as the oxidative, enzymatic, and non-enzymatic antioxidant were assessed. Liver damage was judged histologically. L-Cysteine decreased the activity of alanine aminotransferase and aspartate aminotransferase, as well as improved the level of lipid profile, increased the enzymatic antioxidant (catalase, superoxide dismutase, glutathione peroxidase and glutathione reductase), and decreased the lipid peroxidation. L-Cysteine administration inhibited liver injury of sodium valproate. 相似文献
232.
233.
结合输变电工程环境影响评价实例,参照相应的国家标准,客观阐述了高压输电线路周围电场和磁场的电磁环境影响程度。结果表明,110/220kV高压输电线路周围的电磁场强度值远低于国家标准要求限值,不会对公众生活造成不利影响。 相似文献
234.
光透法定量两相流中流体饱和度的模型及其应用 总被引:2,自引:1,他引:1
基于光透法定量流体饱和度的原理及其在两相流中的应用,设计了两组密封砂箱实验来研究气体或重非水相流体(DNAPL)在饱和孔隙介质中的迁移,观察了气体或DNAPL在孔隙介质中的迁移规律,应用并验证了2个水/气两相流中的光强-饱和度(LIS)模型,特别是建立并应用了适用于NAPL/水两相流系统的2个新LIS模型.结果表明,气体以不规则的"指状"通道向上迁移直到在砂箱顶部聚集,最终形成连续的气体分布;TCE由于自身重力的影响向下迁移直至砂箱底部,最终在砂箱中形成不规则的污染羽并在砂箱底部形成污染池.利用实验结果应用并验证4个光透法模型得到:2个水/气系统中LIS模型(WG-A和WG-B)整体适用于本实验数据;2个NAPL/水系统的LIS模型(NW-A和NW-B)得到与实测资料较吻合的结果,其中基于单个孔隙水驱替假设的模型NW-A与实验结果更加接近,对量化多孔介质中的NAPL/水系统各相饱和度具有一定的参考意义. 相似文献
235.
To investigate how the perceptions and behaviour of visitors to coral reefs are influenced by their prior experience and knowledge
of marine life, a questionnaire-based study was undertaken at sites in the Ras Mohammed National Park and at Sharm El Sheikh,
South Sinai, Egypt. It was evident that over the 10–20 years during which these reefs have deteriorated (mainly due to reef-flat
trampling), there have been interrelated shifts in the nature of visitors making use of them. First, there has been a shift
from experienced divers and snorkellers to inexperienced snorkellers and non-snorkellers with a poorer knowledge of reef biology.
Second, there has been a shift in the predominant nationalities of visitors, from German and British, through Italian, to
Russian. More recent user groups both stated and showed that they had less experience of snorkelling; they also showed less
knowledge of marine life and less interest in learning about it. Visitor perceptions of both the state of the marine life
on the reefs and the acceptability of current visitor numbers also varied between groups. More recent visitor groups and visitors
with less knowledge were more satisfied with reef health. In general, however, visitor perceptions of reef health did not
correlate well with actual reef conditions, probably because more experienced visitors preferred less impacted sites with
which they were nevertheless less satisfied than inexperienced visitors at heavily impacted sites. More recent visitor groups
were also less bothered by crowding on the shore or in the water. Consequently, the apparent “social carrying capacity” of
sites seems to be increasing to a level well above the likely “ecological carrying capacity”. 相似文献
236.
Watson A Glaspell B Christensen N Lachapelle P Sahanatien V Gertsch F 《Environmental management》2007,40(6):880-888
Many public land management agencies are committed to understanding and protecting recreation visitor experiences. Parks Canada
is deeply committed to that objective for visitors to Canada’s National Parks. This 2004 study, informed by a 2003 qualitative
study of visitor experiences and influences on those experiences at Auyuittuq National Park in Nunavut, worked to bring 50
potential elements of visitor experiences down to five articulated dimensions of the experience that is currently being received
at this remote eastern arctic park. A hypothesized set of 17 influences on experiences, also reduced to just two factors with
similar response patterns, and with some items that did not flow into the two factors, were used in a regression analysis
to understand the relationship between experiences and factors of influence. A sample of 61.8% (84) of the total recreation
visitor population 16 years of age or older was surveyed during deregistration after the trip. Knowledge about the dimensions
of the experiences currently received and factors of influence on those experiences can be used to guide selection of indicators
for describing objectives and prescribing monitoring protocol. 相似文献
237.
This paper evaluates how geographical theories of scale can give a more robust understanding of the governance of complex environmental risks. We assess the case of fisheries in Iwaki City, Fukushima Prefecture in Japan following the 2011 nuclear disaster. Fisheries in Iwaki and Fukushima more widely are operating on a trial basis as understanding of the marine radiation situation becomes clearer, however questions remain over whether consumers will buy produce and to what extent full-scale fisheries will resume. Based on empirical fieldwork undertaken in Fukushima plus supporting documentary analysis, we construct a scalar account of post-disaster Iwaki fisheries. We use this to argue that framing post-disaster fisheries governance at the municipal scale rather than the prefectural scale has opened up opportunities for enacting the more two-way forms of risk governance that contemporary environmental issues may require. We also argue locally-situated ‘experts’ (e.g. fisheries extension officers and citizen science groups) play a key role in negotiating citizens’ and fishers’ relationships with larger-scale scientific discourses due to their ability to work across scales, despite having less techno-scientific expertise than their national-level counterparts. In turn, we suggest that in governance of complex environmental issues, policymakers ought to (a) consider how community-level expectations may differ from risk governance processes developed at larger scales; (b) identify key institutions or figures who can work across scales and support them accordingly; and (c) show cognisance to the social effects that may arise from spatial demarcation of environmental problems. 相似文献
238.
The Mexican government has an innovative policy model for biodiversity conservation and rural development that includes permissible use of wildlife within a System of Land Management Units (SUMA, by its Spanish acronym). This co-management approach has been successful in terms of landowner participation, since the SUMA currently covers 38.2 million hectares (nearly 20% of Mexican territory). However, after 18 years of implementation, there has been no comprehensive evaluation by which to assess its effectiveness at national level. This article introduces the SUMA policy, its implementation and outcomes, and proposes a framework for conducting institutional monitoring and evaluation within an adaptive co-management approach. Our methodology comprised analysis of the achievements and challenges reported through interviews with stakeholders, journals and grey literature, and a review of the SUMA Information System (SIS) and its decision-making information needs. As result we have developed a set of 40 environmental, social and economic indicators grouped into five distinct but complementary dimensions within a sustainability framework: (I) Biodiversity conservation,(II) Wildlife management, (III) Economics, (IV) Social welfare and (V) Administration. These indicators can be incorporated into the SIS in order to support program evaluation and strengthen decision-making. Our article provides specific pathways for developing policy-oriented evaluation systems for worldwide biodiversity and conservation initiatives. 相似文献
239.
论地震灾害心理研究的内容与目标 总被引:5,自引:0,他引:5
依据1976年唐山大地震后的现场调查材料,考察了地震灾害给人造成的心理伤害,分析了震灾心理的形成机制和表现特征,提出了地震灾害心理研究的基本内容和目标,同时对地震灾害发生后实施心理救助的问题也做了一些探讨。 相似文献
240.
Colette S. Vogeler Johanna Hornung Nils C. Bandelow 《Journal of Environmental Policy & Planning》2020,22(4):518-530
ABSTRACT Sustainable agriculture implies trade-offs with farm animal welfare. Proposals to increase agricultural productivity and ecological sustainability alike, are often linked to intensification, which may restrict animal welfare. Despite the growing importance of farm animal welfare for the alignment of agricultural and environmental policy, determinants of decision-making at the EU level remain unexplored. This article contributes to closing this research gap, broadening our understanding of why policymakers vote for the enactment of animal welfare policies. Applying the Social Identities in the Policy Process (SIPP) perspective we highlight the role of group membership for individual decision-making. By means of a quantitative analysis of voting behaviour in the European Parliament on two animal welfare policies, we show that different identities are salient. The strongest predictor is political group membership. In case of defections from the group line, the salience of national, sectoral and also demographic identities adds to the understanding of decision-making. 相似文献