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991.
Stefano Ponte 《Agriculture and Human Values》2007,24(2):179-193
Contemporary regulation of food safety incorporates principles of quality management and systemic performance objectives that
used to characterize private standards. Conversely, private standards are covering ground that used to be the realm of regulation.
The nature of the two is becoming increasingly indistinguishable. The case study of the Ugandan fish export industry highlights
how management methods borrowed from private standards can be applied to public regulation to achieve seemingly conflicting
objectives. In the late 1990s, the EU imposed repeated bans on fish imported from Uganda on the basis of food safety concerns.
However, the EU did not provide scientific proof that the fish were actually “unsafe.” Rather, the poor performance of Uganda’s
regulatory and monitoring system was used as justification. Only by fixing “the system” (of regulations and inspections) and
performing the ritual of laboratory testing for all consignments for export to the EU did the Ugandan industry regain its
status as a “safe” source of fish. Yet, gaps and inconsistencies abound in the current Ugandan fish safety management system.
Some operations are by necessity carried out as “rituals of verification.” Given the importance of microbiological tests and
laboratories in the compliance system, “alchemic rituals” provide an appropriate metaphor. These rituals are part and parcel
of a model that reassures the EU fish-eating public that all is under control in Uganda from boat to point of export. As a
consequence, actual non-compliance from boat to landing site allows the fishery to survive as an artisanal operation.
Stefano Ponte
is Senior Researcher at the Danish Institute for International Studies, Copenhagen. His research focuses on the role of standards,
regulation and quality conventions in the governance of agro-food value chains, with particular focus on Africa. He is co-author
of Trading Down: Africa, Value Chains and the Global Economy and The Coffee Paradox: Global Markets, Commodity Trade and the
Elusive Promise of Development. 相似文献
992.
We examine changing production relations in the Mexican tequila industry to explore the ways in which large industrial firms
are using “reverse leasing arrangements,” a form of contract farming, to extend their control over small agave farmers. Under
these arrangements, smallholders rent their parcels to contracting companies who bring in capital, machinery, labor, and other
agricultural inputs. Smallholders do not have access to their land, nor do they make any of the management decisions. We analyze
the factors that have led some producers to participate in reverse leasing arrangements, while allowing other producers to
continue farming independently. In addition, we look at the ways in which farmers are responding to these new production relations
and constraints and the strategies that they are using to regain control over the production process.
相似文献
Sarah BowenEmail: |
993.
Multilineage potential of adult human mesenchymal stem cells 总被引:7,自引:0,他引:7
Pittenger MF Mackay AM Beck SC Jaiswal RK Douglas R Mosca JD Moorman MA Simonetti DW Craig S Marshak DR 《Science (New York, N.Y.)》1999,284(5411):143-147
Human mesenchymal stem cells are thought to be multipotent cells, which are present in adult marrow, that can replicate as undifferentiated cells and that have the potential to differentiate to lineages of mesenchymal tissues, including bone, cartilage, fat, tendon, muscle, and marrow stroma. Cells that have the characteristics of human mesenchymal stem cells were isolated from marrow aspirates of volunteer donors. These cells displayed a stable phenotype and remained as a monolayer in vitro. These adult stem cells could be induced to differentiate exclusively into the adipocytic, chondrocytic, or osteocytic lineages. Individual stem cells were identified that, when expanded to colonies, retained their multilineage potential. 相似文献
994.
Food quality is an important issue on the global agenda, particularly in high- and middle-income economies, but of little concern in designing Mexico’s food policy. Food policy has focused on quantity and in the case of maize, on satisfying domestic demand by supporting large commercial agriculture and importing from abroad. However, and as argued in this paper, obtaining a food staple (maize-tortilla) of quality is also an important issue for rural households and contributes to motivating continued smallholder production. Based on case studies in the rural district of Atlacomulco, in the state of Mexico, as well as in two regions of the state of Chiapas, this paper analyzes the production and consumption strategies of rural households. We focus on goals of food security and quality and note differential trends among households of varying characteristics and local contexts. We find that the motivation of small-scale producers to grow maize should be supported by Mexico’s food policy. 相似文献
995.
996.
Samuel Adjei-Nsiah Cees Leeuwis Ken E. Giller Thom W. Kuyper 《Agriculture and Human Values》2008,25(3):389-403
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.
相似文献
Samuel Adjei-NsiahEmail: |
997.
William H. Friedland 《Agriculture and Human Values》2008,25(2):197-201
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. 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
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
998.
Double-stranded RNA-mediated gene interference (RNAi) in Caenorhabditis elegans systemically inhibits gene expression throughout the organism. To investigate how gene-specific silencing information is transmitted between cells, we constructed a strain that permits visualization of systemic RNAi. We used this strain to identify systemic RNA interference-deficient (sid) loci required to spread gene-silencing information between tissues but not to initiate or maintain an RNAi response. One of these loci, sid-1, encodes a conserved protein with predicted transmembrane domains. SID-1 is expressed in cells sensitive to RNAi, is localized to the cell periphery, and is required cell-autonomously for systemic RNAi. 相似文献
999.
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
1000.
Rational design of peptide-based HIV proteinase inhibitors 总被引:48,自引:0,他引:48
N A Roberts J A Martin D Kinchington A V Broadhurst J C Craig I B Duncan S A Galpin B K Handa J Kay A Kr?hn 《Science (New York, N.Y.)》1990,248(4953):358-361
A series of peptide derivatives based on the transition-state mimetic concept has been designed that inhibit the proteinase from the human immunodeficiency virus (HIV). The more active compounds inhibit both HIV-1 and HIV-2 proteinases in the nanomolar range with little effect at 10 micromolar against the structurally related human aspartic proteinases. Proteolytic cleavage of the HIV-1 gag polyprotein (p55) to the viral structural protein p24 was inhibited in chronically infected CEM cells. Antiviral activity was observed in the nanomolar range (with one compound active below 10 nanomolar) in three different cell systems, as assessed by p24 antigen and syncytium formation. Cytotoxicity was not detected at 10 and 5 micromolar in C8166 and JM cells, respectively, indicating a high therapeutic index for this new class of HIV proteinase inhibitors. 相似文献