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61.
The global scale and rapidity of environmental change is challenging ecologists to reimagine their theoretical principles and management practices. Increasingly, historical ecological conditions are inadequate targets for restoration ecology, geographically circumscribed nature reserves are incapable of protecting all biodiversity, and the precautionary principle applied to management interventions no longer ensures avoidance of ecological harm. In addition, human responses to global environmental changes, such as migration, building of protective infrastructures, and land use change, are having their own negative environmental impacts. We use examples from wildlands, urban, and degraded environments, as well as marine and freshwater ecosystems, to show that human adaptation responses to rapid ecological change can be explicitly designed to benefit biodiversity. This approach, which we call “renewal ecology,” is based on acceptance that environmental change will have transformative effects on coupled human and natural systems and recognizes the need to harmonize biodiversity with human infrastructure, for the benefit of both.  相似文献   
62.
Species ranges often change in relation to multiple environmental and demographic factors. Innovative behaviors may affect these changes by facilitating the use of novel habitats, although this idea has been little explored. Here, we investigate the importance of behavior during range change, using a 25‐year population expansion of Bonelli's eagle in southern Portugal. This unique population is almost exclusively tree nesting, while all other populations in western Europe are predominantly cliff nesting. During 1991–2014, we surveyed nest sites and estimated the year when each breeding territory was established. We approximated the boundaries of 84 territories using Dirichlet tessellation and mapped topography, land cover, and the density of human infrastructures in buffers (250, 500, and 1,000 m) around nest and random sites. We then compared environmental conditions at matching nest and random sites within territories using conditional logistic regression, and used quantile regression to estimate trends in nesting habitats in relation to the year of territory establishment. Most nests (>85%, n = 197) were in eucalypts, maritime pines, and cork oaks. Nest sites were farther from the nests of neighboring territories than random points, and they were in areas with higher terrain roughness, lower cover by agricultural and built‐up areas, and lower road and powerline densities. Nesting habitat selection varied little with year of territory establishment, although nesting in eucalypts increased, while cliff nesting and cork oak nesting, and terrain roughness declined. Our results suggest that the observed expansion of Bonelli's eagles was facilitated by the tree nesting behavior, which allowed the colonization of areas without cliffs. However, all but a very few breeding pairs settled in habitats comparable to those of the initial population nucleus, suggesting that after an initial trigger possibly facilitated by tree nesting, the habitat selection remained largely conservative. Overall, our study supports recent calls to incorporate information on behavior for understanding and predicting species range shifts.  相似文献   
63.
The purpose of this study was to explore how Dutch-speaking children acquire deverbal compounds, particularly in ordering verbs and nouns. English-speaking children form compounds like bottle breaker around 5–6 years of age and make noun-verb reversal errors at younger ages. These errors have been attributed to clausal ordering. Dutch allows more variations in clausal ordering, so Dutch-speaking children might acquire deverbal compounds differently from English-speaking children. In Study 1, we examined the input to a Dutch-speaking child between 4;8 and 5;2 and her compound acquisition. She heard a variety of clausal orderings, mostly with verbs before objects, and her deverbal compounds were already well acquired. In Study 2, we tested 24 Dutch-speaking preschool children’s production and comprehension of novel compounds. They produced many of the same forms as have been reported for English-speaking children, making reversal errors at around the same age. In Study 3, we compared a subset of the Dutch-speaking children with age-matched English monolingual children. We found a slight advantage for the Dutch-speaking children on production but no difference on comprehension. We argue that children’s ordering errors with OV-er compounds are not due to clausal word order but to ordering of other complex word forms.  相似文献   
64.
随着环境污染加剧和人们对自身健康关注度的提高,功能性食品在全球范围内蓬勃发展。彩色稻米作为稻米家族中的一员,由于富含微量元素、花色苷、生物碱等功能性成分,已成为当前功能性食品研究开发的热点之一。本研究利用粳稻品种龙锦1号/香软米1578杂交组合214个F_5家系,对水稻糙米总花色苷含量、粒色等级和千粒重的变异及其相关性进行了分析。糙米粒色等级变异范围为1~9,平均值为4.98,变异系数为57.87%;糙米总花色苷含量变异范围为0~5459.34 mg/kg,平均值为834.47 mg/kg,变异系数为191.96%;糙米千粒重变异范围为11.96~26.24 g,平均值为17.75 g,变异系数为12.89%。糙米总花色苷含量、粒色等级和千粒重在F5家系中不符合正态分布,表现为右偏态,其中糙米总花色苷含量的偏斜程度最大。糙米总花色苷含量和千粒重的峰度系数为正值,表明为尖顶峰;而糙米粒色等级的峰度系数为负值,表明为平顶峰。糙米总花色苷含量与粒色等级呈极显著正相关,相关系数为0.69;糙米总花色苷含量、粒色等级均与千粒重呈极显著负相关,相关系数分别为-0.20和-0.34。与高亲龙锦1号相比,27个家系的糙米总花色苷含量极显著提高,占214个F_5家系的12.62%,为高花色苷水稻种质创新奠定了基础。  相似文献   
65.
进化新征的起源和分化是进化发育生物学研究的核心问题。通过对多细胞生物早期发育调控机制的比较分析,发现亲缘关系较远的生物所共有的一些形态特征受保守的发育调控程序调节(深同源性)。许多创新性状的发生是基于对预先存在的基因或发育调控模块的重复利用和整合。发育基因调控网络在结构和功能上高度模块化,因此不仅可以通过模块拆分和重复征用改变发育程式,而且也增强了调控网络自身的进化力。研究基因调控网络和发育系统的进化动态将有助于更深入地认识生物演化过程中创新性状发生和表型进化的分子机制。  相似文献   
66.
张琇  刘雅琴  倪志婧 《微生物学通报》2010,37(11):1701-1704
微生物学实验是当代生命学科中的一门重要专业必修课。针对民族院校的学生特点和我院生物工程专业的培养特色,阐述将微生物学实验教学体系分为基础验证型、提高设计型和综合研究型3个层次,贯彻"以学生自主实验为主,教师指导为辅"的实验课程教学方针,充分发挥学生在实验教学中的主体作用。在规范基本实验操作的基础上,锻炼学生的自学能力,激发创新意识,培养应用能力。  相似文献   
67.
发现生命现象,理清生命现象的脉络,是认识生命本质的基础。在检索相关文献的基础上,对探究生命现象的方法和规律进行了总结和归纳。从试验材料、试验方法、创新技巧和猜想能力四个方面进行了论述,以便为理解生命现象提供一些参考。  相似文献   
68.
Culturally transmitted traits are observed in a wide array of animal species, yet we understand little about the costs of the behavioural patterns that underlie culture, such as innovation and social learning. We propose that infectious diseases are a significant cost associated with cultural transmission. We investigated two hypotheses that may explain such a connection: that social learning and exploratory behaviours (specifically, innovation and extractive foraging) either compensate for existing infection or increase exposure to infectious agents. We used Bayesian comparative methods, controlling for sampling effort, body mass, group size, geographical range size, terrestriality, latitude and phylogenetic uncertainty. Across 127 primate species, we found a positive association between pathogen richness and rates of innovation, extractive foraging and social learning. This relationship was driven by two independent phenomena: socially contagious diseases were positively associated with rates of social learning, and environmentally transmitted diseases were positively associated with rates of exploration. Because higher pathogen burdens can contribute to morbidity and mortality, we propose that parasitism is a significant cost associated with the behavioural patterns that underpin culture, and that increased pathogen exposure is likely to have played an important role in the evolution of culture in both non-human primates and humans.  相似文献   
69.
70.
目的:探究创新医疗卫生服务管理理念的开展、实施无缝隙对接服务工程的成果以及具体方法。方法:对本院2013年1月-2013年12月期间的门诊量、出住院病人数、人均住院天数、患者满意度等资料进行回顾性的分析,对采用无缝隙对接服务工程的前、后的成果进行对比研究。结果:2013年1月-2013年12月期间本院门诊量、出院人数较去年同期分别增长了9.19%和14.0%;患者平均住院12.1 d,同比减少了0.7 d;患者满意度达到了98.7%,接到投诉312次,同比减少了200余次。结论:无缝对接工程的实施,改造并创新了医疗服务管理的理念,对于提高患者满意度,实现了社会、经济效益的双收具有积极意义。  相似文献   
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