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431.
本文从2008岁首冰雪灾害链的自然态和人文态分析入手,通过对<地球物理灾害链>一书内容梗概的介绍,阐述了灾害链研究工作的新进展,最后试图运用地球系统科学的理论,指出了若干地球物理灾害链对策.  相似文献   
432.
A comparison of two Siberian moth populations from the Altai Republic (feeding on Siberian fir) and the Tyva Republic (feeding on Siberian larch) has revealed no differences between them with respect to ecophysiological parameters of larval growth and feeding on needles of the same conifer species under laboratory conditions. The index of appropriateness of food plants for the larvae from both populations decreases in the series larch > fir > spruce > pine. The age-related dynamics of parameters characterizing the feeding and growth of larvae are independent of the population to which the insects belong.  相似文献   
433.
The regulatory structures underlying United States and European Union policies regarding genetically modified (GM) food and crops are fundamentally different. The US regulates GM foods and crops as end products, applying roughly the same regulatory framework that it does to non GM foods or crops. The EU, on the other hand, regulates products of agricultural biotechnology as the result of a specific production process. Accordingly, it has developed a network of rules that regulate GM foods and crops specifically. As a result, US regulation of GM foods and crops is relatively permissive, whereas EU regulation is relatively restrictive. Why are genetically modified food policies in the United States and the European Union so strikingly different? In the light of the recent World Trade Organization dispute on agricultural biotechnology, it may seem that economic interests are the driving force behind policies. While they are certainly part of the picture, the issue is far more complex. This paper argues that three different elements help explain differences between US and EU GM food policies. First, an investigation of US and European policies of the 1970s and 1980s on recombinant DNA research and of events leading up to early GM food and crop regulation allows a deeper understanding of current policy. Second, scrutinizing underlying values and norms can uncover the beliefs that condition current GM food and crop policy. Third, an analysis of involved actors’ views and levels of success in influencing policy is essential to understanding US and EU policies.  相似文献   
434.
公钥基础设施(PKI)应用中的信任问题与安全解决方案   总被引:3,自引:0,他引:3  
详细论述受信证书链的替换原理、方法和过程,及其引发的用户错误受信问题。通过分析得到安全证书链的长度为小于3,但由于实际应用的业务需要和安全性需要,证书链的长度通常至少为3。最后针对上述问题给出了一种安全解决方案,通过结合存储用户个人证书的USBKEY硬件设备,采用物理信任点代替逻辑信任点来防止受信证书的替换,为用户构建安全可靠的网络信任环境。  相似文献   
435.
基于(火用)分析法的煤炭工业生态链物质能量流动研究   总被引:1,自引:0,他引:1  
从工业生态学角度研究了矿区工业生态系统的工业代谢和工业生态链,建立了矿区物质循环与能量流动分析和效率模型。根据生态效率的理念,矿区发展需要5项关键支撑技术,为合理选择煤炭的产业链延伸途径打下理论基础,促进了矿区的可持续发展。  相似文献   
436.
Sara Pantuliano 《Disasters》2007,31(S1):S77-S90
Despite more than 20 years of distribution of free emergency food in eastern Sudan (38 years in the case of refugees) Global Acute Malnutrition rates are currently the highest in the country. There has been no real improvement in the chronic livelihoods vulnerability that affects people in the region—particularly pastoralists. Food security must be seen from an informed livelihoods perspective. While food aid may still be required as part of transition, WFP must rethink its assistance strategy and advocate for complementarity in the efforts by development actors working across a range of sectors. Alternative models and interventions focused on the rehabilitation of markets and the development of' cargo nets' for the destitute, including cash transfers, must be developed and tested. Land tenure issues should be given particular attention. Food aid will probably remain an important element in the overall response, but its significance relative to other less developed forms of interventions should be reassessed.  相似文献   
437.
Jason Matus 《Disasters》2007,31(S1):S91-S103
Currently, the pace of recovery in the 'Three Areas' is moving faster than the implementation of the Comprehensive Peace Agreement (CPA). This gap is leading to greater imbalances in income, unsustainable urbanization, overexploitation of the environment and resource based conflict. Unless regulated, the likely result will be chronic poverty and an undermining of the success of the CPA. Agencies must be mindful of how they provide assistance so that they support the CPA. The analysis of food security should take place in the context of a larger political, social and economic analysis of the emerging situation. The least developed areas should be prioritised and interventions should provide benefits to the full range of socioeconomic groups. WFP must identify its role in the wider and integrated response. It should support the emerging peace process and the key reforms. If WFP chooses to consolidate its activities, it will require capable strategic partners. If it chooses to invest more in building the capacity of government and community structures, it must improve its skill base and field presence  相似文献   
438.
The Political Import of Intrinsic Objections to Genetically Engineered Food   总被引:2,自引:2,他引:0  
Many people object to genetically engineerehd (GE) food because they believe that it is unnatural or that its creation amounts to playing God. These objections are often referred to as intrinsic objections, and they have been widely criticized in the agricultural bioethics literature as being unsound, incompatible with modern science, religious, inchoate, and based on emotion instead of reason. Many of their critics also argue that even if these objections did have some merit as ethicalobjections, their quasi-religious nature means that they are entirely irrelevant when interpreted aspolitical objections regarding what public policy ought to be. In this paper, we argue that this widespread view is false. Intrinsic objections have much more political import than has previously been recognized, and indeed the requirements of political liberalism and its associated idea of liberal neutrality, once properly understood, protect intrinsic objections from many of the most common objections. That is, policy-makers may not legitimately base public policy on grounds that are inconsistent with intrinsic objections, even when they believe those objections to be flawed in the ways mentioned above. This means that in the context of a political debate about GE food, the discussion should not center on the substantive merits of the intrinsic objections themselves but rather on the appropriate political norms for achieving democratically legitimate policy on issues that touch people’s deepest religious and moral beliefs.  相似文献   
439.
本文以实证分析的方法,以宁夏地区为例,通过研究该地区2003年200户退耕户和100户非退耕户之间。以及二者与1999年实行退耕还林政策前的人均粮食消费量和人均食品支出水平的变化,认为退耕户的粮食安全程度比非退耕户和退耕前的农户有了显著的提高,这种提高与农民的人均收入水平和人均耕地面积呈正相关,而与粮食播种面积比重呈负相关,因而可得得出结论:在生态脆弱地区实行退耕还林政策并不会影响当地农民的粮食安全。  相似文献   
440.
有机食品发展与生态保护政策相关性分析   总被引:2,自引:0,他引:2  
通过对有机食品发展与“三农“问题、生物多样性保护、生态省建设、清洁生产、食品安全等国家生态保护政策之间的相关性进行了分析.在我国积极发展有机食品,是在农业领域内贯彻国家生态保护政策的具体体现.  相似文献   
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