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排序方式: 共有193条查询结果,搜索用时 140 毫秒
141.
Laurence C. Becker 《Human ecology: an interdisciplinary journal》2000,28(2):219-250
This study of a rural Malian community in West Africa investigates food procurement patterns that combine subsistence grain production with a variety of income generating activities. It finds dependence on food purchases widespread and revenue from the own-account activities of nonhousehold heads essential to food security. Gender and the wealth of households are found to influence some, but not all, income generating activities and expenditures. Three household food procurement profiles are identified: investment in cattle, market gardens and bush extraction, and remittances. The case study village has agroecological characteristics and market proximity, which set it and other urban hinterland villages apart from the more cotton- and cattle-based zones of southern Mali. Own-account income generating activities may be able to increase revenue for women and junior men through a reallocation of household resources without entirely undermining the basis for a larger subsistence-oriented household. 相似文献
142.
回顾2014年值得关注的3种药物(Sovaldi、Anoro Ellipta和Zydelig)的上市和销售情况。重点介绍2015年值得关注药
物的适应证、上市申请、临床开发情况以及市场前景展望等 相似文献
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146.
介绍了中国的卫生机构状况、2007—2013 年中国药品医疗终端规模,以及中国医院终端化学药和中成药各大类药品市场份额状况,并分别对中国医院终端化学药和中成药各大类重点品种的销售额Top 10 进行了分析。 相似文献
147.
《Animal : an international journal of animal bioscience》2020,14(7):1546-1554
Economic margins on pig farms are small, and changing slaughter weights may increase farm profitability. However, one can question if the optimal slaughter weight is the same for each sex. On three farms, crossbred pigs (n = 1128) were used to determine the effect of sex and slaughter weight on performance, carcass quality and gross margin per pig place per year. On each farm, an equal number of entire males (EMs), barrows (BAs), immunocastrates (IC) and gilts (GIs) were housed separately in group pens. Pens were randomly divided into three categories of different slaughter weights: 105, 117 and 130 kg BW. In BA, the high average daily feed intake (ADFI) and the lower capacity to gain muscle led to a higher feed conversion ratio (FCR) and lower lean meat percentage in comparison to EM and IC. In all sexes, ADFI and FCR increased with an increasing slaughter weight but the effect of slaughter weight on carcass quality varied between sexes. In BA and GI, slaughter weight had no effect on carcass quality, but in EM and IC, carcass quality improved at higher slaughter weights. Gross margin per pig place per year was calculated as gross margin per pig × barn turnover per year, taking into account fixed costs per round, feed costs and output price per pig. The slaughter weight that gained the highest gross margin per year differed between sexes. Slaughtering BA and GI at 130 kg BW, compared to 105 or 117 kg BW, decreased the gross margin per pig place per year due to the lower margin per pig and barn turnover at higher weights. In IC and EM, no difference in gross margin per pig place per year could be demonstrated between slaughtering at 105, 117 or 130 kg BW. In IC, the increasing gross margin per pig with increasing slaughter weights counteracted with the lower barn turnover. In EM, gross margin per pig did not differ between slaughter weights, but the effect of barn turnover was too small to demonstrate significant differences between slaughter weights on gross margin per pig place per year. In conclusion, slaughter weight has an impact on profitability in BA and GI: they should not be slaughtered at 130 kg BW but at lower weights, but no effect could be demonstrated in EM and IC. 相似文献
148.
Sara R. Farris 《Ethnic and racial studies》2013,36(9):1505-1525
This article provides a theoretical framework for analysing discrimination against second-generation immigrant girls in education and the labour market by proposing an intersectional approach. Drawing upon selected elements of the findings of our Neskak Gora Project – a qualitative research conducted between 2009 and 2011 in Denmark, France, Italy, the Netherlands, Spain and the UK and funded by the EC Daphne III Programme – we show that the intersection of class, gender and ‘race’/ethnicity, which is at play at the structural, institutional and discursive levels of systems of intersectional discrimination, works in variable ways. While gendered educational structures seem partly to benefit female immigrant youth at school, gendered disadvantages are experienced particularly in the transition to the labour market. This highlights the necessary acknowledgement of the ‘discontinuity’ of axes of inequality that are manifested in different ways, according to specific contexts, institutional settings and moments of the individual's life cycle. 相似文献
149.
Meghan Elizabeth Kallman 《Ethnic and racial studies》2013,36(5):759-774
Using ethnographic data on Boston's Haymarket Square, this paper demonstrates how public space and a market opportunity can generate solidarity among people of different ethnicities in the form of a cosmopolitan canopy, and how a single ethnic tradition can nurture an open, public multi-ethnic environment. The paper illustrates how Haymarket vendors' treatment of ethnic and racial difference is actively deployed in the construction of new groups that largely transcend such distinctions. This article outlines the mechanisms by which a cosmopolitan canopy is sustained, and how it serves a constructive social function within the city. 相似文献
150.
Plants engage in multiple root symbioses that offer varying degrees of benefit. We asked how variation in partner quality persists using a resource‐ratio model of population growth. We considered the plant's ability to preferentially allocate carbon to mutualists and competition for plant carbon between mutualist and nonmutualist symbionts. We treated carbon as two nutritionally interchangeable, but temporally separated, resources—carbon allocated indiscriminately for the construction of the symbiosis, and carbon preferentially allocated to the mutualist after symbiosis establishment and assessment. This approach demonstrated that coexistence of mutualists and nonmutualists is possible when fidelity of the plant to the mutualist and the cost of mutualism mediate resource competition. Furthermore, it allowed us to trace symbiont population dynamics given varying degrees of carbon allocation. Specifically, coexistence occurs at intermediate levels of preferential allocation. Our findings are consistent with previous empirical studies as well the application of biological market theory to plantroot symbioses. 相似文献