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191.
192.
差异蛋白质组学在水产动物环境生理学中的研究进展   总被引:1,自引:0,他引:1  
随着蛋白质组学技术的发展,差异蛋白质组学的研究已引起国内外学者的广泛关注.差异蛋白质组学主要通过寻找、筛选和鉴定由某些因素引起的样本之间的差异蛋白质谱,揭示生物机体生理和病理过程以及对外界环境刺激的反应途径和调控机制,同时获得对某些关键蛋白的定性和功能分析,从分子水平上解析更多的生命现象本质.本文着重介绍了差异蛋白质组学在凝胶和非凝胶技术方面的最新技术方法,综述了差异蛋白质组学在水产动物养殖环境生理学与环境毒理学方面的研究进展,为从蛋白质水平上解析水产动物生理调控机制提供了技术支撑.  相似文献   
193.
为了提升微生物诱导碳酸盐沉淀(MICP)技术在海洋环境下对钙质砂的加固效果,在以往研究的基础上,设计进行了人工海水环境下巴氏芽孢杆菌多梯度人工驯化培养试验,并结合MICP固化钙质砂柱的力学试验和微细观结构分析,对巴氏芽孢杆菌的驯化效果进行了综合评价。结果表明:(1)海水环境下五梯度驯化后细菌的菌液浓度可达到淡水环境的97%以上,其与胶结液作用后碳酸盐的生成量较淡水环境下有一定幅度提高;(2)驯化后的巴氏芽孢杆菌具有很好的温度适应能力,在10~30℃温度下均有较好的MICP性能;(3)海水环境下加固的钙质砂柱无论是碳酸盐生成量还是无侧限抗压强度均较未驯化前高,尤其是五梯度驯化后的细菌,驯化后的细菌菌体变小,在海水环境生成的碳酸盐(碳酸钙和碳酸镁)晶体更小,更加致密,能更好地填充钙质砂颗粒的孔隙并胶结相邻的钙质砂颗粒,具有更优异的MICP性能。相关研究思路和方法可为MICP技术在海洋环境钙质砂地基加固方面的研究与应用提供参考。  相似文献   
194.

Cultural geographers often ascribe early animal domestications to the spiritual propitiation practices of ancient peoples, an interpretation that is not widely shared. This paper evaluates the sacrifice theory against Near Eastern archaeological data and refutes the idea that ritual sacrifice could have induced the earliest animal domestications of the Near East. The earliest domestications were the outcome of essentially ecological and economic processes which later gave rise to the sacrificial practices referred to by cultural geographers.  相似文献   
195.
The emerging subfield of historical animal geography provides an opportunity to trace the origins and evolutions of how affective logics framing the conservation of an animal species are co-constituted through embodied interaction between humans and nonhumans, revealing the dynamic ways in which charismatic species are imagined into and out of positions of priority within conservation agendas. This article takes an interest in the shifting perception of predatory species in the environmental conservation movement in the United States, looking to the appearance of jaguars (Panthera onca) in the work of prominent U.S. nature writers Theodore Roosevelt, Ernest Thompson Seton, and Aldo Leopold in the early- to mid-twentieth century. These human–jaguar entanglements reveal a period marked by dynamic changes in the ways in which interspecies encounters were constituted in place; a layering on of affective logics that reveal the complicated origins, practices, and potentialities at the outset of the modern conservation movement. The resulting narratives and images of predatory nature were taken up into dynamic assemblages of jaguar-ness, influencing the formation of new logics that framed public perceptions of predatory natures and provoking a reconsideration of long-held attitudes and policies toward these species.  相似文献   
196.
Researching media coverage of climate change may shed light on the different configurations of global and domestic factors affecting journalism and politics. This article analyzes climate change coverage in Portugal from 2007 to 2014 in comparison with 14 other countries. It shows that the Portuguese press tends to reproduce the global political agenda on climate change, mainly focusing on international events associated with global political decision-making processes, instead of providing a domesticated coverage, as observed in other countries. National and local levels of action are thus obscured. The interplay between global and domestic factors—including characteristics of Portugal’s press and politics, such as national political leaders’ lack of mobilization and communication on climate change, media’s deference to powerful sources, and reliance on international news feeds—creates the conditions for global politics to play an hegemonic role in media representations, which is likely to influence public engagement with climate change.  相似文献   
197.
Of the four types of terrestrial haulout periods undertaken by southern elephant seals Mirounga leonina, only the purpose of the winter haulout is unknown. Returning to a haulout site from distant pelagic foraging grounds bears significant costs in terms of increased energy expenditure, reduced foraging time and increased exposure to predation; therefore, each haulout must serve a purpose. We examined the hypothesis that the winter haulout serves to maintain familiarity with the natal site, thereby increasing site fidelity. To this end, we analysed a long-term mark-recapture dataset for female southern elephant seals at Marion Island, Southern Ocean. Results indicate that, whereas greater natal site fidelity as primiparous females was associated with recorded presence ashore at the study site during the winter haulout as immatures, this was not the case for multiparous females. Furthermore, recorded presence ashore during both the moult haulouts as immatures, and all haulouts as immatures, irrespective of haulout type, was also associated with increased site fidelity. This suggests that any haulout at the natal island as an immature seal, whether for the moult or winter haulout, assists in maintaining site fidelity. Therefore, while the winter haulout facilitates greater natal site fidelity, whether this is the sole reason for this terrestrial period remains uncertain.  相似文献   
198.
动物性饵料对脉红螺(Rapana venosa)幼体的吸引性研究   总被引:1,自引:0,他引:1  
采用生态学方法进行了新鲜和煮熟的动物性饵料对脉红螺(Rapana venosa)浮游幼体的吸引作用研究。结果表明, 脉红螺浮游幼体在4螺层期是食性转换期, 且在幼体到达3螺层后期的第1—6天是投放附着基和动物性饵料的最佳时期。此外, 新鲜和熟的双壳贝类肉对脉红螺幼体有明显的吸引力, 吸附于新鲜贝肉上的4螺层幼体占吸附幼体总数的48.61%, 显著大于其它螺层幼体; 脉红螺幼体选择新鲜紫贻贝肉的比例为33.75%, 显著大于菲律宾蛤仔(24.08%)、中国蛤蜊(18.97%)和长牡蛎(23.19%); 而熟贝肉中, 长牡蛎对幼体的吸引作用显著大于紫贻贝、菲律宾蛤仔、中国蛤蜊、海湾扇贝边粉和空白对照; 新鲜紫贻贝和熟长牡蛎肉具有作为脉红螺幼体食性转换期动物性饵料的开发潜力。  相似文献   
199.
全新世中期以来西辽河流域动物地理与环境变迁   总被引:3,自引:1,他引:3  
王守春 《地理研究》2002,21(6):715-722
自全新世中期以来 ,西辽河流域动物群的种类成分有很大变化。全新世中期 ,野猪和鹿科动物是这里最主要的大型食草动物。公元初期 ,野马等草原动物占有一定地位。中世纪的辽代时期 ,鹿科动物成为这里最主要大型食草动物 ,同时 ,有适应沼泽环境的麋鹿。直到清代初期 ,野马在动物群中还占有一定地位。清代中期 ,大型食肉动物虎、豹、熊分布较广泛 ,清代晚期 ,其分布迅速减少直至消失。动物地理的变化在一定程度上反映了环境的变化。  相似文献   
200.
为实现对社会、公众在震前“打个招呼”的强烈愿望,探讨了实现临震预报的可能性,提出了建立规范化实验观察场(哨)应注意的几个问题.  相似文献   
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