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1.
The concept of intrinsic value and transgenic animals 总被引:1,自引:0,他引:1
H. Verhoog 《Journal of Agricultural and Environmental Ethics》1992,5(2):147-160
The creation of transgenic animals by means of modern techniques of genetic manipulation is evaluated in the light of different interpretations of the concept of intrinsic value. The zoocentric interpretation, emphasizing the suffering of individual, sentient animals, is described as an extension of the anthropocentric interpretation. In a biocentric or ecocentric approach the concept of intrinsic value first of all denotes independence of humans and a non-instrumental relation to animals. In the zoocentric approach of Bernard Rollin, genetic engineering is seen as a morally neutral tool, as long as the animal does not suffer as a result of it. Robert Colwell who defends an ecocentric ethic, makes a sharp distinction between wild animals and domesticated animals. Genetic manipulation of wild species is a serious moral issue, in contrast to genetic manipulation of domesticated species which is no problem at all for Colwell. Both authors do not take the species-specific nature (or telos) of domesticated animals seriously. When domestication is seen as a process between the two poles of the wild animal and the human construct (which can be patented), the technique of genetic manipulation can only be seen as a further encroachment upon the intrinsic value of animals. At the level of molecular biology, the concept of an animal's telos loses its meaning. 相似文献
2.
旅游目的地网络空间结构及其复杂性研究——野三坡旅游地案例实证 总被引:1,自引:1,他引:0
复杂性是旅游目的地网络化发展的必然趋势,是认识旅游地网络空间结构与组织特征的重要研究手段。论文以河北省野三坡旅游地为例,通过构建旅游联系强度模型,建立旅游地空间网络,并运用TOP网络空间分析以及复杂网络理论,揭示旅游地网络空间结构与组织的复杂性特征。研究发现:1)旅游地网络具有空间集聚性,形成了以核心景区为中心,由中心城镇、乡村社区和特色园区共同构成的空间集聚单元,并体现出“邻近连接”与“择优连接”的双重特性;2)旅游地网络服从幂律分布,具有无标度网络特性;3)每个节点的前三名和前五名旅游联系强度网络(Top3和Top5网络)具有较小的平均路径长度、较大的集聚系数,呈现出典型的“小世界网络”特征;4)旅游地网络是典型的异配型网络,度-度呈负相关,而网络节点的集聚系数与其度值之间存在近似的倒数关系,因此具有层次性。 相似文献
3.
The increasing use of the landscape by humans has led to important diminutions of natural surfaces. The remaining patches
of wild habitat are small and isolated from each other among a matrix of inhospitable land-uses. This habitat fragmentation,
by disabling population movements and stopping their spread to new habitats, is a major threat to the survival of numerous
plant and animal species. We developed a general model, adaptable for specific species, capable of identifying suitable habitat
patches within fragmented landscapes and investigating the capacity of populations to move between these patches. This approach
combines GIS analysis of a landscape, with spatial dynamic modeling. Suitable habitat is identified using a threshold area
to perimeter ratio. Potential movement pathways of species between habitat patches are modeled using a cellular automaton.
Habitat connectivity is estimated by overlaying habitat patches with movement pathways. The maximum potential population is
calculated within and between connected habitat patches and potential risk of inbreeding within meta-populations is considered.
The model was tested on a sample map and applied to scenario maps of predicted land-use change in the Peoria Tri-county region
(IL). It (1) showed area of natural area alone was insufficient to estimate the consequences on animal populations; (2) underscored
the necessity to use approaches investigating the effect of land-use change spatially through the landscape and the importance
of considering species-specific life history characteristics; and (3) highlighted the model's potential utility as an indicator
of species likelihood to be affected negatively by land-use scenarios and therefore requiring detailed investigation. 相似文献
4.
Bhanarkar AD Srivastava A Joseph AE Kumar R 《Environmental monitoring and assessment》2005,109(1-3):73-80
Air pollution in the workplace environment due to industrial operation have been found to cause serious occupational health
hazard. Similarly, heat stress is still most neglected occupational hazard in the tropical and subtropical countries like
India. The hot climate augments the heat exposure close to sources like furnaces. In this study an attempt is made to assess
air pollution and heat exposure levels to workers in the workplace environment in glass manufacturing unit located in the
State of Gujarat, India. Samples for workplace air quality were collected for SPM, SO2, NO2 and CO2 at eight locations. Results of workplace air quality showed 8-hourly average concentrations of SPM: 165–9118 μg/m3, SO2: 6–9 μg/m3 and NO2: 5–42 μg/m3, which were below the threshold limit values of workplace environment. The level of CO2 in workplace air of the plant was found to be in the range 827–2886 μg/m3, which was below TLV but much higher than the normal concentration for CO2 in the air (585 mg/m3). Indoor heat exposure was studied near the furnace and at various locations in an industrial complex for glass manufacturing.
The heat exposure parameters including the air temperature, the wet bulb temperature, and the globe parameters were measured.
The Wet Bulb Globe Temperature (WBGT), an indicator of heat, exceeded ACGIH TLVs limits most of the time at all the locations
in workplace areas. The recommended duration of work and rest have also been estimated. 相似文献
5.
Awofolu OR 《Environmental monitoring and assessment》2005,105(1-3):431-447
The concentration of trace metals (Cd, Cu, Pb and Zn) in a total of 144 samples of grass, soil and lower animal (earthworm, Lybrodrilus violaceous) were collected and analysed for their metallic content. Levels of cadmium ranged from 0.01–0.07 g g–1; 0.01–0.12 g g–1 and from trace–0.05 g g–1 dry weight for plant, soil and animal samples respectively. Mean concentration of copper ranged 0.10–1.48 g g–1; 0.10–2.90 g g–1 and 0.01–0.08 g g–1 for samples in similar order as above. The levels of Pb varied from 0.01–0.14 g g–1; 0.02–0.23 g g–1 and from trace–0.07 g g–1 while that of Zn ranged from 0.19–1.80 g g–1; 0.51–3.35 g g–1and 0.01–0.08 g g–1 also in the same order of samples as mentioned above. Levels of metals in soil samples were higher than the background levels with the exception of Zn but lower than European Union (EU) limits. The results generally revealed the presence of metals in plant and animal samples and metal dynamics up the food chain is highly possible. Acceptable recoveries of the spiking experiment validate the experimental protocol. 相似文献
6.
Tom Regan 《Journal of Agricultural and Environmental Ethics》1995,8(2):171-180
Some feminist philosophers criticize the idea of human rights because, they allege, it encapsulates male bias; it is therefore misguided, in their view, to extend moral rights to non-human animals. I argue that the feminist criticism is misguided. Ideas are not biased in favour of men simply because they originate with men, nor are ideas themselves biased in favour of men because men have used them prejudicially. As for the position that women should abandon theories of rights and embrace an ethic that emphasizes care: women who made this choice would not so much liberate themselves from the patriarchy as they would conform to its representation of women as emotional, subjective and irrational. There is, then, no good reason to withhold ascribing rights to non-human animals, based on the criticisms of rights made by some feminists.Some of the material in the discussion of the feminist critique of rights originally appeared in my The Case for Animal Rights: A Decade's Passing inA Quarter Century of Value Inquiry: Presidential Addresses of the American Society of Value Inquiry, edited by Richard T. Hull, pp. 451–455. Amsterdam and Atlanta, GA: Rodopi, 1994. These passages are reprinted with the permission of the editor and publisher, whose thoughtful co-operation is gratefully acknowledged. 相似文献
7.
本文对Ⅱ套SRU的标定结果,进行了比较详细的技术分析,在此基础上,对装置及其运行状况作出了评价,并提出了一些建设。 相似文献
8.
本文针对目前地勘单元安全工作的现状,提出强化安全管理的对策,并结合当前国内安全生产的严峻形势,对安全管理工作进行了思考。 相似文献
9.
刘红卫 《安全.健康和环境》2003,3(8):3-5,16
通过分析柴油加氢装置的腐蚀现象及腐蚀原因,找出了因腐蚀造成的安全隐患。通过化验分析推断出发生腐蚀的重点部位。采用了加注缓蚀剂等有效的防腐措施,使腐蚀得到有效控制,保证了装置的安全运行。 相似文献
10.
城市特定生境下土壤动物的生态分布 总被引:7,自引:0,他引:7
通过对2002年9月至2003年3月间上海3种生境类型下土壤动物的调查,共捕获土壤动物3863个,属27个类群,其中绿地中的类群数和个体数多于农田和废弃地。农田中的优势类群为弹尾类(collembola)和蚯蚓类(Oligchaeta);废弃地中的优势类群为线虫类(Nematoda)、双翅类幼虫(Diptera(L))、螨类(Acarina)和弹尾类(Collembola);绿地中的优势类群为线蚓类(Enchytraeidae)和弹尾类(Collembola)。绿地中的优势类群为农田和绿地中的Simpson,优势度指数除12月外均高于废弃地,与Pielou均匀性指数相反,但Shannon-Wiener多样性指数规律不明显。土壤动物的数量和种类在10月份最多,随天气转冷而减少,绿地和废弃地中土壤动物个体数于次年3月份逐渐增多,农田中的于次年1月逐渐增多。表聚性显著,Ⅰ层(0~5cm)最多,Ⅱ(5~10cm)、Ⅲ(10~15cm)两层差异不大。 相似文献