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1.
While the US Supreme Court was considering two related cases involving the constitutionality of same-sex marriage, one major question informing that decision was whether scientific research had achieved consensus regarding how children of same-sex couples fare. Determining the extent of consensus has become a key aspect of how social science evidence and testimony is accepted by the courts. Here, we show how a method of analyzing temporal patterns in citation networks can be used to assess the state of social scientific literature as a means to inform just such a question. Patterns of clustering within these citation networks reveal whether and when consensus arises within a scientific field. We find that the literature on outcomes for children of same-sex parents is marked by scientific consensus that they experience “no differences” compared to children from other parental configurations.  相似文献   
2.
Understanding the risk of biological invasions associated with particular transport pathways and source regions is critical for implementing effective biosecurity management. This may require both a model for physical connectedness between regions, and a measure of environmental similarity, so as to quantify the potential for a species to be transported from a given region and to survive at a destination region. We present an analysis of integrated biosecurity risk into Australia, based on flights and shipping data from each global geopolitical region, and an adaptation of the “range bagging” method to determine environmental matching between regions. Here, we describe global patterns of environmental matching and highlight those regions with many physical connections. We classify patterns of global invasion risk (high to low) into Australian states and territories. We validate our analysis by comparison with global presence data for 844 phytophagous insect pest species, and produce a list of high‐risk species not previously known to be present in Australia. We determined that, of the insect pest species used for validation, the species most likely to be present in Australia were those also present in geopolitical regions with high transport connectivity to Australia, and those regions that were geographically close, and had similar environments.  相似文献   
3.
进化论思想与唯物史观同为近代中国影响广泛的思想。二者的传入时间接近,并且都经历了中国化的过程。随着进化论思想在现代遭到了越来越多的批判和质疑,唯物史观早期传播和发展的历程也经历了重新的审视。文章从近代思想史发展的事实出发,重新厘清两种思想的关系,并具体论证马克思的唯物史观能否从广义上归结为一种进化论的思想,以及进化论思想在中国是否经历了一个向唯物史观转变的历程。  相似文献   
4.
试论农业生物基因工程技术产业化   总被引:1,自引:0,他引:1  
农业生物基因工程技术产业化尚处在起步阶段 ,但是已经呈现迅猛发展势头。到目前为止 ,很多种农作物已经有了不同改良性状的转基因新品种 ,部分农作物的不同改良性状的转基因新品种已经进入商品化种植 ,并且商品化种植的面积逐年扩大。转基因农作物商品化种植面积主要分布在发达国家 ,广大发展中国家分布面积不大。农业生物基因工程技术产业化跳出了以前农业生产的基本思路 ,通过改造农作物以增强其适应不良环境的能力来发展农业生产。农业生物基因工程技术产业化面临人们对农业生物基因工程技术产业化是否会危害人类和环境的担心、农业生物基因工程技术不完善、农业生物基因工程技术研究和开发体制落后等问题。需要从强化农业生物基因工程技术安全管理和知识宣传、强化农业生物基因工程技术研究、深化农业生物基因工程技术研究和开发体制改革等方面解决这些问题  相似文献   
5.
研究表明,学生学习科学的过程是一种由前概念向科学概念转变的过程。学生头脑中形成的与科学概念不一致的相异构想是造成学生学习困难的重要原因。本文分析了学生在生物学学习中相异构想的成因及来源,并在此基础上提出了生物学教学中相异构想的转变模式及策略。  相似文献   
6.
当代中国美学:走向生态美学   总被引:4,自引:0,他引:4  
当代中国美学出现了多元化趋势,其中后实践美学对实践美学的超越、生态美学的异军突起等都是美学界引人注目的理论现象.我们认为 ,无论实践美学还是后实践美学,都是某一阶段的重要理论现象,它随特定历史环境而产生,并在一定历史条件下被另一种学说所替代.生态美学的出现一方面适应了社会的发展要求,另一方面又全面激活了美学的理论研究与中国传统文化的现代转型.因此,当代中国美学走向应该是生态美学.  相似文献   
7.
从细胞因子的产生、作用特点及其对运动训练刺激所产生的生物学反应等方面。阐述了细胞因子对运动训练的反应受许多因素的影响,这一过程及其机制十分复杂.随着研究的深入,许多发现势必促使人们对运动损伤及其康复、运动与健康促进等一系列问题产生新的研究兴趣.  相似文献   
8.
This study examines housing quality among three groups of single-parent women: white, African-American, and Hispanic. Three indicators of housing quality—crowding, affordability, and satisfaction—are used to discover the extent to which these groups experience housing problems. This study also explores differences and similarities in the factors that precipitate problems in housing quality for these three groups of single parents. Findings suggest important differences and similarities in the nature of housing quality problems among white, African-American, and Hispanic single-parent women. The specified variables explained about 20% of the variance in crowding, housing affordability, and housing satisfaction. On measures of objective and subjective housing quality, white single mothers are better housed than their African-American or Hispanic counterparts. Hispanic single mothers have the largest housing cost burden and average more persons per household than the other groups. African-Americans are twice as likely as either group to live in low-quality housing and reported the lowest average satisfaction with their housing. Her research interests include housing and neighborhood assessment and women and public policy issues. She has recently published articles inUrban Affairs Quarterly andHousing and Society on housing and neighborhood assessment criteria among black urban households and the housing cost burden of various groups of female-headed households. She received her Ph.D. from Ohio State University. Her research interests include the housing adjustment behavior of women and public policy. She has recently completed her thesis on the role of noncustodial parents in determining the quality of life of their children. She is also the recipient of the Tessie Agan Award for research excellence from the American Association of Housing Educators for a paper titled “Unterstanding Constraints and Residential Satisfaction among Low-Income Single-Parent Families.”  相似文献   
9.
外来物种入侵的生态危害   总被引:2,自引:0,他引:2  
外来物种是指某种生物从原来的分布区域扩展到了一个新的地区,在新的区域里进行繁殖扩散并维持下去。这些外来物种会对入侵地的生态环境及生物多样性造成极其严重的威胁和破坏。  相似文献   
10.
生物多样性保护与知识产权   总被引:1,自引:0,他引:1  
生物多样性保护与知识产权存在较大的关联性,《生物多样性条约》的相关条款与知识产权密切相关,围绕生物资源保护与利用的知识产权理论不断发展,我国的相关法律制度也应加以完善。  相似文献   
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