首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   30篇
  免费   1篇
  2019年   4篇
  2018年   5篇
  2017年   1篇
  2016年   1篇
  2015年   2篇
  2014年   3篇
  2013年   7篇
  2012年   1篇
  2011年   1篇
  2009年   1篇
  2007年   1篇
  1992年   1篇
  1977年   1篇
  1972年   1篇
  1969年   1篇
排序方式: 共有31条查询结果,搜索用时 31 毫秒
1.
When traditional methods for measuring economic welfare are scarce or unreliable, heights and BMIs are now well-accepted measurements that represent biological conditions during economic development. Weight, after controlling for height, is an additional measure for current net nutrition. Little is known about how weights varied among Mexicans living in the nineteenth century American West. Between 1870 and 1920, average Mexican weight was low and remained constant. Mexican farmers had the heaviest weights, and unskilled worker weights were low. Weight of Mexican-born individuals were higher than Mexicans born in the United States at low weights but lower at high weights. For combined characteristics, weight varied the most with age, an uncontrollable characteristic, indicating that nineteenth century Mexican current net nutrition varied the most with factors over which they had no control.  相似文献   
2.
When people first inhabited the Remote Oceanic region of the world at 1500 b.c., they generated archaeological sites attesting to their practical coastal adaptations in tandem with their ceremonial traditions, wherein water figured vitally in daily living and ritual performance. Of eight known first-settlement sites in the Mariana Islands, Ritidian in Guam uniquely incorporates one residential habitation plus two caves related to water collection, pictographs, consumption of unusual foods, and use of exceptionally decorative objects. The inter-connected findings clarify what was “special” about the special-use caves, in total articulating a fuller sense of cultural life and landscape than otherwise could be possible.  相似文献   
3.
Body mass index (BMI) values reflect the net balance between nutrition, work effort, and calories consumed to fight disease. Nineteenth-century prison records in the United States demonstrate that the BMI values of blacks and whites were distributed symmetrically; neither underweight nor obese individuals were common among the working class. BMI values declined throughout the nineteenth century. By modern standards, however, nineteenth-century BMIs were in healthy weight ranges, though the biological living standards in rural areas exceeded those in urban areas. The increase in BMIs during the twentieth century did not have its origin in the nineteenth century.  相似文献   
4.

In the 1950s, a small group of political, scientific and business leaders in West Germany were determined to build a center for nuclear reactor research and development. They characterized the venture as a three-way partnership, intending to set an example for a scientific-technical age. The project was eventually carried out, but not without much conflict. The attempts at cooperation show parties with divergent sets of criteria that they only inadequately reconciled, and the struggles display their conflicted understandings of both the public-private boundary and the scientific role. New archival material lets us inspect more accurately the workings of the proposed collaboration. It shows how the conflicts developed in practice, despite all parties' expressions of commitment to cooperation.  相似文献   
5.
This article examines congruence between public opinion and politicians’ positions on same-sex marriage in the Australian House of Representatives from 2012 to 2016. In contrast median voter theorem and other office-motivated frameworks, Australian federal politicians have largely ignored majority opinion, which has been supportive of same-sex marriage for a decade. Using a unique dataset (n?=?601,550) of voter preferences collected during the 2013 federal election, and collated Hansard and media data, we compare public opinion on same-sex marriage with politicians’ public positions. We find a status quo bias, suggesting the influence of special interest groups in this policy area. Yet, we also find parliamentarians are responsive to public opinion once it reaches a critical level, and that very low opposition to same-sex marriage in an electorate predicts policy support from its MP, which varies by party and over time.  相似文献   
6.
7.
8.
9.
10.
Located in the key junction between mainland China and Island Southeast Asia, Taiwan is of great significance for our understanding of the southeastward dispersal of rice agriculture in the prehistoric period. Until now, quite limited archaeobotanical work has been done in this region. In eastern Taiwan, no archaeological evidence of rice agriculture has been obtained, probably owing to the poor preservation conditions for plant macroremains. Here, we report a new discovery of 4200-year-old domesticated rice remains at the Chaolaiqiao site, which for the first time in detail demonstrates the ancient practice of rice agriculture in this area. Based on a combination of factors that include a rice-based plant subsistence strategy, the mid-Holocene limits to available farmland and the fast-growing Taiwan Neolithic population from settlement pattern data, we infer that this contradiction in eastern Taiwan between land-dependent agriculture and limited suitable farmland encouraged a population movement out of Taiwan during the Middle Neolithic period.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号