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991.
利用人GCSF基因组基因和cDNA基因作为目的片段,将其受控于2.6kb的小鼠乳清酸蛋白(WAP)基因的调控区下,通过显微注射法获得了两只整合有人GCSF转基因小鼠,通过繁殖建立了稳定的转基因系.一些表型参数测定表明,转基因鼠与正常鼠无明显差别,为对转基因动物进行安全性评价提供了依据 相似文献
992.
清代的环境保护思想 总被引:1,自引:1,他引:0
丁俊娜 《中国环境管理干部学院学报》2005,15(2):97-99
清代的"天人合一"、"与天争胜"、倡导保护自然资源、反对暴殄天物的思想对我国的环境保护事业具有史鉴意义. 相似文献
993.
农地冲突是当前我国农村经济发展和城镇化进程中的普遍问题,在—些地方相当突出,严重影响了农村的社会稳定和经济发展,探讨农地冲突的原因有助于化解农村矛盾及构建和谐繁荣的农村社区。本文利用笔者在湖北和湖南两省收集到的数据,应用Logit概率模型实证分析了农地分配制度、非农就业收入及其差距和人力资本等可能引起农地冲突的因素的影响。与通常的看法不同,本文并没有发现农地分配制度是农地冲突的显著诱因,原因可能在于我国的农地在改革初期是按人口或劳动力平均分配的,其后的调整大多也是经农民自主协商按照市场规则完成的,并没有引起农民的明显不满,因而也就没有成为农地冲突的诱因。本文的研究结果还表明,非农就业收入、非农就业收入差距和家庭人力资本对农地冲突的影响显著,非农就业收入越低,其差距越小,家庭人力资本越多,农地冲突发生的概率越大,是农地冲突的主要诱因。这表明非农就业收入越少,农民通过非农就业增加家庭收入的隧道效应越弱,对农业收入的依赖性越大,农地就越重要,农地冲突越容易发生;家庭男性成员越多,家庭社会地位越高,在打架斗殴和上访诉讼中越占优势,农地冲突也越容易爆发。因此,为了减少农地冲突,应采取切实措施,促进农村劳动力向非农部门转移,加强农村法制建设,限制丛林行为。 相似文献
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995.
陇东南贫困地区人力资源开发滞后,制约了经济的快速发展。以控制人口数量,大力推进教育发展和城市化进程,优化人力资源配置和激励机制为主导的人力资源开发战略对策成为促进陇东南贫困地区经济发展的必然选择。 相似文献
996.
Abstract: By 2050, 70% of the world's population will live in urban areas. In many cases urbanization reduces the richness and abundance of native species. Living in highly modified environments with fewer opportunities to interact directly with a diversity of native species may adversely affect residents’ personal well‐being and emotional connection to nature. We assessed the personal well‐being, neighborhood well‐being (a measure of a person's satisfaction with their neighborhood), and level of connection to nature of over 1000 residents in 36 residential neighborhoods in southeastern Australia. We modeled these response variables as a function of natural features of each neighborhood (e.g., species richness and abundance of birds, density of plants, and amount of vegetation cover) and demographic characteristics of surveyed residents. Vegetation cover had the strongest positive relations with personal well‐being, whereas residents’ level of connection to nature was weakly related to variation in species richness and abundance of birds and density of plants. Demographic characteristics such as age and level of activity explained the greatest proportion of variance in well‐being and connection to nature. Nevertheless, when controlling for variation in demographic characteristics (examples were provided above), neighborhood well‐being was positively related to a range of natural features, including species richness and abundance of birds, and vegetation cover. Demographic characteristics and how well‐being was quantified strongly influenced our results, and we suggest demography and metrics of well‐being must be considered when attempting to determine relations between the urban environment and human well‐being. 相似文献
997.
SUMMARY An interactive and incremental developmental approach to sustainable development is proposed. It requires broad public participation, is based on the development of a shared value system for civic society and norms which determine the behaviour of states. It is aimed at building commitment rather than directing change. This is achieved by simultaneoulsy harnessing the notions of ‘positive human survival’ adopted from Global Security theory and a co-evolutionary approach to human socio-economic constructs. Modern threats to Nation States can be regarded as ‘threats without enemies’, are not compatible with traditional views of sovereignty, and confronting such threats frequently requires co-operative behaviour and good neigbourliness from states. Principles likely to underpin an evolving shared value system for Nation states and civil society include: democracy, equity and diversity. In order to deal with the uncertainty of evolving socio-economic constructs and the conceptual pluralism inherent in modern societies, public agencies need to develop significant mediation, negotiation and facilitation skills. This view has significant implications for National and Regional policy, and the democratisation of information and the development of early warning capabilities about potential threats to human security are pivotal. 相似文献
998.
Freedom C. Onuoha 《Disasters》2009,33(3):369-389
Since its discovery in Nigeria in 1956 crude oil has been a source of mixed blessing to the country. It is believed to have generated enormous wealth, but it has also claimed a great many lives. Scholarly attention on the impact of oil on security in Nigeria has largely focused on internal conflicts rather than on how disasters associated with oil pipeline vandalisation have impacted on human security in terms of causing bodily injuries and death, destroying livelihoods and fracturing families. This paper examines how pipeline vandalisation affects human security in these ways. It identifies women and children as those who are hardest hit and questions why the poor are the most vulnerable in oil pipeline disasters in this country. It recommends the adoption of a comprehensive and integrated framework of disaster management that will ensure prompt response to key early warning signs, risk-reduction and appropriate mitigation and management strategies. 相似文献
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BLAKE R. HOSSACK MICHAEL J. ADAMS CHRISTOPHER A. PEARL KRISTINE W. WILSON EVELYN L. BULL KRISTIN LOHR DEBRA PATLA DAVID S. PILLIOD JASON M. JONES KEVIN K. WHEELER SAMUEL P. MCKAY PAUL STEPHEN CORN 《Conservation biology》2013,27(6):1410-1420
Despite the high profile of amphibian declines and the increasing threat of drought and fragmentation to aquatic ecosystems, few studies have examined long‐term rates of change for a single species across a large geographic area. We analyzed growth in annual egg‐mass counts of the Columbia spotted frog (Rana luteiventris) across the northwestern United States, an area encompassing 3 genetic clades. On the basis of data collected by multiple partners from 98 water bodies between 1991 and 2011, we used state‐space and linear‐regression models to measure effects of patch characteristics, frequency of summer drought, and wetland restoration on population growth. Abundance increased in the 2 clades with greatest decline history, but declined where populations are considered most secure. Population growth was negatively associated with temporary hydroperiods and landscape modification (measured by the human footprint index), but was similar in modified and natural water bodies. The effect of drought was mediated by the size of the water body: populations in large water bodies maintained positive growth despite drought, whereas drought magnified declines in small water bodies. Rapid growth in restored wetlands in areas of historical population declines provided strong evidence of successful management. Our results highlight the importance of maintaining large areas of habitat and underscore the greater vulnerability of small areas of habitat to environmental stochasticity. Similar long‐term growth rates in modified and natural water bodies and rapid, positive responses to restoration suggest pond construction and other forms of management can effectively increase population growth. These tools are likely to become increasingly important to mitigate effects of increased drought expected from global climate change. Papeles de las Características del Fragmento, Frecuencia de Sequía y Restauración en las Tendencias a Largo Plazo de un Anfibio Ampliamente Distribuido 相似文献