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961.
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
962.
The coevolution of parochial altruism and war 总被引:1,自引:0,他引:1
Altruism-benefiting fellow group members at a cost to oneself-and parochialism-hostility toward individuals not of one's own ethnic, racial, or other group-are common human behaviors. The intersection of the two-which we term "parochial altruism"-is puzzling from an evolutionary perspective because altruistic or parochial behavior reduces one's payoffs by comparison to what one would gain by eschewing these behaviors. But parochial altruism could have evolved if parochialism promoted intergroup hostilities and the combination of altruism and parochialism contributed to success in these conflicts. Our game-theoretic analysis and agent-based simulations show that under conditions likely to have been experienced by late Pleistocene and early Holocene humans, neither parochialism nor altruism would have been viable singly, but by promoting group conflict, they could have evolved jointly. 相似文献
963.
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: |
964.
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
965.
Kinoshita T Miura A Choi Y Kinoshita Y Cao X Jacobsen SE Fischer RL Kakutani T 《Science (New York, N.Y.)》2004,303(5657):521-523
966.
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
967.
Du J Zhou Y Su X Yu JJ Khan S Jiang H Kim J Woo J Kim JH Choi BH He B Chen W Zhang S Cerione RA Auwerx J Hao Q Lin H 《Science (New York, N.Y.)》2011,334(6057):806-809
Silent information regulator 2 (Sir2) proteins (sirtuins) are nicotinamide adenine dinucleotide-dependent deacetylases that regulate important biological processes. Mammals have seven sirtuins, Sirt1 to Sirt7. Four of them (Sirt4 to Sirt7) have no detectable or very weak deacetylase activity. We found that Sirt5 is an efficient protein lysine desuccinylase and demalonylase in vitro. The preference for succinyl and malonyl groups was explained by the presence of an arginine residue (Arg(105)) and tyrosine residue (Tyr(102)) in the acyl pocket of Sirt5. Several mammalian proteins were identified with mass spectrometry to have succinyl or malonyl lysine modifications. Deletion of Sirt5 in mice appeared to increase the level of succinylation on carbamoyl phosphate synthase 1, which is a known target of Sirt5. Thus, protein lysine succinylation may represent a posttranslational modification that can be reversed by Sirt5 in vivo. 相似文献
968.
Against the neoliberal steamroller? The Biosafety Protocol and the social regulation of agricultural biotechnologies 总被引:1,自引:0,他引:1
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
969.
The charge transport mechanism of a wire can be revealed by how its electrical resistance varies with length. We have measured the resistance and current-voltage characteristics of conjugated molecular wires ranging in length from 1 to 7 nanometers, connected between metal electrodes. We observe the theoretically predicted change in direct-current transport from tunneling to hopping as a function of systematically controlled wire length. We also demonstrate that site-specific disruption of conjugation in the wires greatly increases resistance in the hopping regime but has only a small effect in the tunneling regime. These nanoscale transport measurements elucidate the role of molecular length and bond architecture on molecular conductivity and open opportunities for greater understanding of electrical transport in conjugated polymer films. 相似文献
970.