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201.
Practitioners and advocates of community food security (CFS) envision food systems that are decentralized, environmentally-sound over a long time-frame, supportive of collective rather than only individual needs, effective in assuring equitable food access, and created by democratic decision-making. These themes are loosely connected in literature about CFS, with no logical linkages among them. Clear articulation in a theoretical framework is needed for CFS to be effective as a guide for policy and action. CFS theory should delimit the level of analysis (i.e., what are the boundaries of community); show how CFS relates to individual, household, and national food security and explain emergent properties, which are important at the community level of analysis; point to the best indicators of CFS or its lack; clarify the determinants of CFS; and clarify the stages of movement toward CFS. This theoretical base would allow researchers to develop valid and reliable measures, and allow practitioners to weigh alternative options to create strategic plans. A theoretical base also would help establish common ground with potential partners by making the connections to anti-hunger work, sustainable agriculture, and community development clear.  相似文献   
202.
转基因大豆存在的问题及应对措施   总被引:6,自引:0,他引:6  
随着分子生物学和基因工程技术的发展,转基因植物研究取得了飞速发展。但是,转基因植物所带来的争议也从未间断过。近年来,我国进口的大豆中有很多是转基因大豆,它是否对人体健康、我国大豆品种资源及生态环境造成影响,越来越引起人们的关注。论述了世界转基因大豆的现状、优缺点和引发的争议,并提出一些建议。  相似文献   
203.
PCR-DGGE技术及其在发酵食品微生物研究中的应用   总被引:1,自引:0,他引:1  
江芸  高峰  徐幸莲  周光宏 《安徽农业科学》2007,35(21):6591-6593
多聚酶链反应-变性梯度凝胶电泳分析技术(PCR-DGGE)是近年来微生物学研究中应用较广泛的分子技术之一。介绍了DGGE的基本原理及其在食品微生物学研究中的应用,着重阐述了PCR-DGGE在发酵食品研究中的应用进展。  相似文献   
204.
生物技术在水稻超高产育种中的应用   总被引:2,自引:0,他引:2  
水稻是我国主要粮食作物,对确保国家粮食安全起到举足轻重的作用。水稻单产潜力在经历了矮化育种和杂交水稻两次重大突破后,出现长期踌躇不前。水稻育种学家正在积极探索利用新种质、新技术,提高水稻单位面积的产量。水稻基因组测序计划的实施和完成,水稻高密度分子标记连锁图谱和各种近等基因系群体的构建,重要农艺性状的QTL不断被精细定位,越来越多的重要发送的基因被克隆及功能分析,转基因技术的广泛应用,功能基因组学迅速地发展,这些为研究复杂农艺性状的分子机理提供机遇,也为生物技术、分子标记辅助选择育种技术广泛应用于水稻品种改良,实现水稻高产、优质、广适应性综合性状改良取得重大突破提供了新契机。  相似文献   
205.
Advocates of environmental sustainability and social justice increasingly pursue their goals through the promotion of so-called “green” products such as locally grown organic produce. While many scholars support this strategy, others criticize it harshly, arguing that environmental degradation and social injustice are inherent results of capitalism and that positive social change must be achieved through collective action. This study draws upon 18 months of ethnographic fieldwork at two farmers markets located in demographically different parts of the San Francisco Bay Area to examine how market managers, vendors, and regular customers negotiate tensions between their economic strategies and environmental sustainability and social justice goals. Managers, vendors, and customers emphasize the ethical rather than financial motivations of their markets through comparisons to capitalist, industrial agriculture and through attention to perceived economic sacrifices made by market vendors. They also portray economic strategies as a pragmatic choice, pointing to failed efforts to achieve justice and sustainability through policy change as well as difficulties funding and sustaining non-profit organizations. While market managers, vendors, and customers deny any difficulties pursuing justice and sustainability through local economics, the need for vendors to sustain their livelihoods does sometimes interfere with their social justice goals. This has consequences for the function of each market.
Alison Hope AlkonEmail:

Alison Hope Alkon   is a Ph.D. candidate in the Department of Sociology at the University of California, Davis. Her research examines how efforts to create environmental protection and social justice operate in a market context.  相似文献   
206.
综述了生物技术在橡胶树育种中的应用,主要包括组织培养技术、染色体工程技术、分子标记技术、基因工程技术等方面的内容;并展望了其在橡胶树育种中的前景。  相似文献   
207.
The US food retailing industry continues to concentrate and consolidate. Power in the agriculture, food, and nutrition system has shifted from producers to processors, and is now shifting to retailers. Currently, only eight food-retailing corporations control the majority of food sales in the United States. Expanding on previous research by Lyson and Raymer (2000, Agriculture and Human Values 17: 199–208), this paper examines the characteristics of the boards of directors of the leading food retailing corporations and the indirect interlocks that bind the food retailers into a corporate community. Rachel Schwartz is a PhD Candidate in the Department of Development Sociology at Cornell University. Her research interests are focused on the relationship between food retailers and food consumers in the United States, especially in regards to the construction of the concept of “choice.” Thomas Lyson was Liberty Hyde Bailey Professor in the Department of Development Sociology at Cornell University. His interests included the relationship of agriculture and food systems on community economic development and population health. His most recent book, Civic Agriculture, developed a problem-solving model for food and agriculture issues. Dr. Lyson passed away in December 2006.  相似文献   
208.
The metaphor of the food system,dominant in current research approaches to sustainableagriculture, mirrors the productionist paradigm, whichreduces our relationship to land and food to theproduction and consumption of commodities. Theenactment of the familiar values of nourishment andhospitality is what the goal of sustainableagriculture would amount to in terms of our day to daylived experience. The metaphor of an earthen bowl asa theory of food and agriculture can embody thesevalues such that broader change might be achievedthrough embracing the idea and practice of theories asnourishing and theorizing as hospitable.  相似文献   
209.
Since the turn of the lastcentury, Michigan farmers, elevators, and stategovernment have used production and processstandards to shape the dry bean industry totheir interests and set a worldwide standardfor quality dry beans. Over the last 20 years,however, multinational agro/food firms haveintroduced their market criteria into standardssetting, and recent changes in Michigan beanstandards largely accommodate the interests ofthese firms. A review of the changes in thesestandards over time allows us to explore howconcepts of accountability and control improveour understanding of changes in the structureand operation of food production and marketing.What is the measure of state governmentaccountability to corporate capital and to thestate's bean farmers? In what ways can farmersuse standards to re-assert their priorities andgain a greater measure of influence overmarketing? What challenges do changing qualitystandards pose for public research as well asfor the institutions representing Michiganfarmers and elevators?  相似文献   
210.
This paper provides a conceptual framework to explain why disparities may exist in food safety code compliance by food stores in different neighborhoods. Explanations include market dynamics, community characteristics, retailer attributes, inspector characteristics, and enforcement approaches, and interactions among the factors. A preliminary and limited empirical test of some of these relationships in Detroit, Michigan shows a higher rate of food safety violations by stores in poorer neighborhoods and in neighborhoods with higher concentrations of African-American residents. Stores inspected by female inspectors also scored higher numbers of critical violations, suggesting a need for greater examination of the social relations associated with enforcement interactions in food safety studies.
Kameshwari PothukuchiEmail:

Kameshwari Pothukuchi   PhD, is Associate Professor of Urban Planning at Wayne State University. She conducts research on issues related to urban food security, including grocery stores, community gardens, and community and regional food planning. A policy guide on community and regional food planning, co-authored by her, was recently adopted by the American Planning Association (). Rayman Mohamed   PhD, is Assistant Professor of Urban Planning at Wayne State University. He conducts research on land use and environmental planning. His recent articles examine decision making by developers, the economics of conservation subdivisions, and the relationship between sprawl and the costs of infrastructure. David A. Gebben   is a graduate student of agricultural economics and a research assistant in the Global Urban Studies Program at Michigan State University.  相似文献   
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