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951.
This study reports on action research efforts that were aimed at developing institutional arrangements beneficial for soil fertility improvement. Three stages of action research are described and analyzed. We initially began by bringing stakeholders together in a platform to engage in a collaborative design of new arrangements. However, this effort was stymied mainly because conditions conducive for learning and negotiation were lacking. We then proceeded to support experimentation with alternative arrangements initiated by individual landowners and migrant farmers. The implementation of these arrangements too ran into difficulties due to intra-family dynamics and ambiguities regarding land tenure. Further investigations to find out how ambiguities could be tackled revealed that the local actors themselves had taken initiatives towards developing institutional innovations to reduce ambiguities. However, there is still considerable scope for further development of these self-organized innovations. The article ends with a reflection on inter-disciplinary action research, where it is argued that making “mistakes” is an inherent and necessary characteristic in action research that aims to address complex social issues.
Samuel Adjei-NsiahEmail:
  相似文献   
952.
The reaction to conventional agriculture and food systems has generated a host of alternative social movements in the past several decades. Many progressive agrifood researchers have researched these movements, exploring their strengths, weaknesses, and failures. Most such research is abstracted from the movements themselves. This paper proposes a new way of self-organization that, while fulfilling traditional university demands on researchers, will provide research support for progressive agrifood movements by transcending the boundaries of disciplines and individual universities.
William H. FriedlandEmail:

William H. Friedland   is Professor Emeritus at the University of California, Santa Cruz where his research continues on commodity systems, wine and grapes, the globalization of agriculture and food, and exploring ways to strengthen alternative social movements to subvert the dominant paradigm.  相似文献   
953.
Within-field variations in potential grain yield may be due to variations in plant available soil water. Different water holding capacities affect yield differently in different years depending on weather. By estimating plant-water availability in different weathers, scenarios could be created of how yield potential and thereby fertilizer demand may vary within fields. To test this, measured cereal grain yields from a dry, a wet and an intermediate year were compared with different soil moisture related variables in a Swedish arable field consisting of clayey and sandy areas. Soil water budget calculations based on weather data and maximum plant available water (PAW), estimated from soil type and rooting data, were used to assess drought. A reasonable correlation between estimated and measured soil moisture was achieved. In the dry year, drought days explained differences in yield between the clayey and the sandy soil, but yield was better explained directly by maximum PAW, elevation, clay content and soil electrical conductivity (SEC). Yield correlated significantly with SEC and elevation within the sandy soil in the dry year and within the clayey soil in the wet year, probably due to water and nitrogen limitation respectively. Dense SEC, elevation and yield data were therefore used to divide the field into management zones representing different risk levels for drought and waterlogging. These could be used as a decision support tool for site-specific N fertilization, since both drought and waterlogging affect N fertilization demand.  相似文献   
954.
Genomic imprinting causes parental origin-specific monoallelic gene expression through differential DNA methylation established in the parental germ line. However, the mechanisms underlying how specific sequences are selectively methylated are not fully understood. We have found that the components of the PIWI-interacting RNA (piRNA) pathway are required for de novo methylation of the differentially methylated region (DMR) of the imprinted mouse Rasgrf1 locus, but not other paternally imprinted loci. A retrotransposon sequence within a noncoding RNA spanning the DMR was targeted by piRNAs generated from a different locus. A direct repeat in the DMR, which is required for the methylation and imprinting of Rasgrf1, served as a promoter for this RNA. We propose a model in which piRNAs and a target RNA direct the sequence-specific methylation of Rasgrf1.  相似文献   
955.
Through a discursive and organizational analysis we seek to understand the Biosafety Protocol and the place of socioeconomic regulation of agricultural biotechnology in it. The literature on the Protocol has been fairly extensive, but little of it has explored debates over socioeconomic regulation during the negotiation process or the regulatory requirements specified in the final document. This case is especially important at a time when the spread of neoliberalism is increasingly associated with deregulation, because it sheds light on the conditions under which circumvention of the market is deemed legitimate and socio-economic regulation of agricultural technology is possible. Daniel Lee Kleinman is a professor in the Department of Rural Sociology at the University of Wisconsin, Madison, where he is also affiliated with the Holtz Center for Science and Technology Studies and the Integrated Liberal Studies Program. He is the author and editor of a number of books, including Impure Cultures: University Biology and the World of Commerce (2003). Abby J. Kinchy is a PhD candidate in the Departments of Sociology and Rural Sociology at the University of Wisconsin, Madison. Her current research examines the controversies surrounding the genetic “contamination” of Mexican maize and Canadian canola.  相似文献   
956.
The observation of the regulation of fast protein dynamics in a cellular context requires the development of reliable technologies. Here, a signal regulation cascade reliant on the stimulus-dependent acceleration of the bidirectional flow of mitogen-activated protein kinase (extracellular signal-regulated kinase) across the nuclear envelope was visualized by reversible protein highlighting. Light-induced conversion between the bright and dark states of a monomeric fluorescent protein engineered from a novel coral protein was employed. Because of its photochromic properties, the protein could be highlighted, erased, and highlighted again in a nondestructive manner, allowing direct observation of regulated fast nucleocytoplasmic shuttling of key signaling molecules.  相似文献   
957.
958.
The economics of harvesting wheat based on input management zones in the northern wheatbelt of Western Australia was studied using a simulated field of regular dimensions with varying zone sizes and layouts. Fertilizer application rates and crop yield and quality data from field trials of input management were used to estimate the gross crop revenue and harvesting costs from the different field layouts and zone combinations. As a general observation there was no consistency in the results; harvesting by zone generated more gross income in some combinations of field layout and yield quantity scenarios, but not in others. However, there were key factors in determining whether it was profitable to harvest by zone. These were prior knowledge of the potential yield and quality characteristics of grain from each zone in a field, and the layout of zones within a field.  相似文献   
959.
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   
960.
Engagement for transformation: Value webs for local food system development   总被引:1,自引:0,他引:1  
Engagement happens when academics and non-academics form partnerships to create mutual understanding, and then take action together. An example is the “value web” work associated with W. K. Kellogg Foundation’s Food Systems Higher Education–Community Partnership. Partners nationally work on local food systems development by building value webs. “Value chains,” a concept with considerable currency in the private sector, involves creating non-hierarchical relationships among otherwise disparate actors and entities to achieve collective common goals. The value web concept is extended herein by separating the values of the web itself, such as the value of collaboration, from values “in” the web, such as credence values associated with a product or service. By sharing and discussing case examples of work underway around the United States, the authors make a case for employing the value webs concept to represent a strategy for local food systems development, specifically, and for higher education–community partnerships, generally.
Daniel R. BlockEmail:

Daniel R. Block   is an associate professor of geography and coordinator of the Frederick Blum Neighborhood Assistance Center at Chicago State University. His current research focuses on food access issues in urban environments, particularly in Chicago. Michael Thompson   is an assistant professor at Oregon State University, and a Seafood and Fisheries specialist for Oregon Sea Grant Extension. Primary areas of research include fisheries management, seafood quality/handling, and seafood product development. Jill Euken   is an industrial specialist for biobased products for Iowa State University Extension/CIRAS, and deputy director, ISU Bioeconomy Institute. She was part of the steering team for the Iowa Value Chain Partnership for Sustainable Agriculture and led the Bioeconomy Working Group. Toni Liquori   is a nutritionist, teacher and food activist with a long time interest in the design, implementation, and evaluation of school-based intervention programs and coalition building for activism around food related issues, as well as teaching and training in public health. Frank Fear   is senior associate dean, College of Agriculture and Natural Resources; and professor, in the Department of Community, Agriculture, Recreation and Resources Studies; and Senior Outreach Fellow at Michigan State University. He is lead author of Coming to Critical Engagement (University Press of America, 2006), an analysis of the engagement movement in higher education; and recently completed two terms as president of the Greater Lansing Food Bank. Sherill Baldwin   is ecology director at Mercy Center at Madison, Connecticut, a spiritual retreat and conference center. She previously provided consulting services to CitySeed, Inc. in New Haven (CT) and to Frank Fear and the W. K. Kellogg Foundation for a community learning project related to sustainable food systems. She has an MS in Resource Development from Michigan State University and a BA in Solid Waste Management from the University of Massachusetts.  相似文献   
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