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91.
Traditional food supply systems, like municipal public markets (MPM), are in crisis. Nevertheless, MPMs continue to demonstrate importance in the lives of the cities. In this article we discuss the case of Mexico City and the importance of the public markets for its neighbourhoods. We present the results of two research projects, completed in Mexico City at two different historical times and interpreted longitudinally. The results demonstrate the importance of socio-economic relationships for MPM's survival and potential. The article concludes with public policy recommendations to permit conservation, given the MPM's importance for the city's social cohesion.  相似文献   
92.
Farmer-to-farmer extension (FFE) is playing a complementary role to formal extension services in facilitating the spread of agricultural technologies and improving farmers’ capacities. The effectiveness and sustainability of such programmes depend on volunteer farmer trainers (VFTs) having technical skills and overcoming process-related challenges that hinder them from achieving the desired outcomes. This article uses quantitative and qualitative data collected from seven sites to explore the challenges experienced by VFTs as they share their knowledge on livestock feed innovations in a dairy development project in Kenya. Sustainable opportunities for enhancing VFTs’ performance are discussed.  相似文献   
93.
Concerns about the decline of rural agricultural communities have recently refocused on new economic opportunities available in regional food production. This article analyses three on-the-ground case studies of rural development projects in Tasmania, Australia that aimed to develop new regional food opportunities. It analyses these projects to identify how local food producers can create viable economic alternatives in rural settings. The projects illustrate that the existence of regional food assets alone is not enough to guarantee economic development success: rural producers need connections into relevant knowledge networks if they are to identify and respond to new agro-food market opportunities.  相似文献   
94.
While substantial literature is available on the determinants of small-scale farmers’ participation in collective action, and the welfare impacts of producing and/or marketing collectively, studies on the likely implications of organisational form on producers’ collective behaviour remain scant. This article attempts to address this knowledge gap by using an example of different forms of small-scale mushroom-producing groups in Swaziland. Given the importance of collective action in sub-Saharan Africa, the overall results of this article provide valuable insights into alternative means of coordinating commercial small-scale agricultural activities, which can improve producers’ ultimate benefits while reducing the likelihood of internal free-riding.  相似文献   
95.
This article describes a collaborative research for development project that used participatory methods to engage smallholder farmers in Uganda in post-harvest aflatoxin management. It is based primarily on qualitative research with peanut growers tracing ‘the path of the peanut’ through their hand-drawn maps and journal writing. By focusing on everyday life and including recipes and drawings, this research encouraged women's participation and emphasised women's roles. A unique partnership among universities, women's organisations, and farmers created an environment of mutual learning and produced a book documenting food preparation and other post-harvest practices as part of a study and capacity-building effort on peanuts and aflatoxins.  相似文献   
96.
《清史稿·刑法志》夸大了清代律与例之间的冲突 ,一味抬高了例的地位 ,认为例优于律 ,甚至“以例破律” ,“以例代律” ,而律则“多成虚文”。本文引证史料 ,对此观点提出质疑 ,论证了律为主导 ,“以例辅律”才是律例关系的主流。  相似文献   
97.
心肌及传导组织内3种蛋白的变化与SMDS的相关性   总被引:2,自引:0,他引:2  
目的 观察心肌及传导组织内肌动蛋白、血浆白蛋白及纤维连接蛋白的染色变化,探讨青壮年猝死综合征(SMDS)死后诊断的新方法。方法 应用免疫组化S-P法,对SMDS及冠心病猝死者心肌及传导系统内肌动蛋白、血浆白蛋白和纤维连接蛋白的进行染色观察。结果 22例SMDS例猝死者心肌及传导系统内的肌动蛋白缺染17例;血浆白蛋白染色阳性18例;纤维连接蛋白染色阳性15例。并发现在SMDS中,8例有CCS严重病变。结论 心肌及传导系统内血浆蛋白、肌动蛋白改变与SMDS密切相关,部分SMDS病例死前存在早期心肌缺血或梗死的改变。  相似文献   
98.
应用3′RACE法降落式扩增并克隆了猪水泡病病毒(SVDV)HK/70株基因组3′端的真实序列.测序结果表明,所扩增的目的基因片段长4 200 nt,包括非结构蛋白编码区(P2和P3)、3′端非编码区和poly(A)尾,其中3′NTR位于终止密码子TAA之后,长99 nt,poly(A)至少含有74个腺嘌呤碱基.经与参考毒株进行序列比较,结果显示, HK/70株与J1′73、H/3′76和AUG/22/90株的核苷酸同源性较高,为99.0%(仅第65位碱基不同),而与NET/1/92参考毒株的核苷酸同源性较低,为83.3%,与人柯萨奇病毒B5 UK/54株(UK/54-CB5)的同源性为75.7%.同时对3′NTR的二级结构进行分析,并与参考毒株和CB5毒株的二级结构进行了比较.结果表明,它们具有协同变异性,有共同的祖先,显示出3′NTR存在支持其功能所必需的一些结构域.  相似文献   
99.
This paper examines the relationship between a mother's age at first childbirth and the delinquent behavior of her children. Using data from the Rochester Youth Development Study (RYDS), an ongoing longitudinal study of adolescent development, we found that children born to mothers who began childbearing at a young age were more prone to general delinquency, violence, and arrest than were children born to mothers who began childbearing when they were older. This “early first‐birth effect” was far larger in white and Hispanic families than in African‐American families. Mediating analyses found that the early first‐birth effect was most attributable to the unstable composition of families in which early childbearing occurs. That said, a substantial portion of the effect remains unmediated.  相似文献   
100.
研究近代中国各种变革的理论范式有两种:"武装斗争的革命范式"和"现代化理论范式".笔者以为,还可以有第三种研究范式,即转型社会理论范式.在转型社会理论范式中,近代三次变革与当今改革具有一定程度上的共构性.近代三次变革所表现出来的经济改革与政治改革的脱节、权力资源的匮乏、无理又无节的症垢恰好也是当前改革开放应该极力避免而又极易堕入其中的问题.  相似文献   
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