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21.
Philip McMichael 《Agriculture and Human Values》2009,26(4):281-295
The food regime concept is a key to unlock not only structured moments and transitions in the history of capitalist food relations,
but also the history of capitalism itself. It is not about food per se, but about the relations within which food is produced,
and through which capitalism is produced and reproduced. It provides, then, a fruitful perspective on the so-called ‘world
food crisis’ of 2007–2008. This paper argues that the crisis stems from a long-term cycle of fossil-fuel dependence of industrial
capitalism, combined with the inflation-producing effects of current biofuel offsets and financial speculation, and the concentration
and centralization of agribusiness capital stemming from the enabling conjunctural policies of the corporate food regime.
Rising costs, related to peak oil and fuel crop substitutes, combine with monopoly pricing by agribusiness to inflate food
prices, globally transmitted under the liberalized terms of finance and trade associated with neoliberal policies. 相似文献
22.
Tomasec P Braud VM Rickards C Powell MB McSharry BP Gadola S Cerundolo V Borysiewicz LK McMichael AJ Wilkinson GW 《Science (New York, N.Y.)》2000,287(5455):1031
The nonclassical major histocompatibility complex (MHC) class I molecule HLA-E inhibits natural killer (NK) cell-mediated lysis by interacting with CD94/NKG2A receptors. Surface expression of HLA-E depends on binding of conserved peptides derived from MHC class I molecules. The same peptide is present in the leader sequence of the human cytomegalovirus (HCMV) glycoprotein UL40 (gpUL40). It is shown that, independently of the transporter associated with antigen processing, gpUL40 can up-regulate expression of HLA-E, which protects targets from NK cell lysis. While classical MHC class I molecules are down-regulated, HLA-E is up-regulated by HCMV. Induction of HLA-E surface expression by gpUL40 may represent an escape route for HCMV. 相似文献
23.
Estimating the mass of asteroid 253 mathilde from tracking data during the NEAR flyby 总被引:1,自引:0,他引:1
DK Yeomans J Barriot DW Dunham RW Farquhar JD Giorgini CE Helfrich AS Konopliv JV McAdams JK Miller WM Owen DJ Scheeres SP Synnott BG Williams 《Science (New York, N.Y.)》1997,278(5346):2106-2109
The terminal navigation of the Near Earth Asteroid Rendezvous (NEAR) spacecraft during its close flyby of asteroid 253 Mathilde involved coordinated efforts to determine the heliocentric orbits of the spacecraft and Mathilde and then to determine the relative trajectory of the spacecraft with respect to Mathilde. The gravitational perturbation of Mathilde on the passing spacecraft was apparent in the spacecraft tracking data. As a result of the accurate targeting achieved, these data could be used to determine Mathilde's mass as 1.033 (+/- 0.044) x 10(20) grams. Coupled with a volume estimate provided by the NEAR imaging team, this mass suggests a low bulk density for Mathilde of 1.3 grams per cubic centimeter. 相似文献
24.
The structure of the upper atmosphere of mars: In situ accelerometer measurements from mars global surveyor 总被引:1,自引:0,他引:1
GM Keating SW Bougher RW Zurek RH Tolson GJ Cancro SN Noll JS Parker TJ Schellenberg RW Shane BL Wilkerson JR Murphy JL Hollingsworth RM Haberle M Joshi JC Pearl BJ Conrath MD Smith RT Clancy RC Blanchard RG Wilmoth DF Rault TZ Martin DT Lyons PB Esposito MD Johnston al et 《Science (New York, N.Y.)》1998,279(5357):1672-1676
The Mars Global Surveyor (MGS) z-axis accelerometer has obtained over 200 vertical structures of thermospheric density, temperature, and pressure, ranging from 110 to 170 kilometers, compared to only three previous such vertical structures. In November 1997, a regional dust storm in the Southern Hemisphere triggered an unexpectedly large thermospheric response at mid-northern latitudes, increasing the altitude of thermospheric pressure surfaces there by as much as 8 kilometers and indicating a strong global thermospheric response to a regional dust storm. Throughout the MGS mission, thermospheric density bulges have been detected on opposite sides of the planet near 90 degreesE and 90 degreesW, in the vicinity of maximum terrain heights. This wave 2 pattern may be caused by topographically-forced planetary waves propagating up from the lower atmosphere. 相似文献
25.
Surface Deformation and Lower Crustal Flow in Eastern Tibet 总被引:99,自引:0,他引:99
LH Royden BC Burchfiel RW King E Wang Z Chen F Shen Y Liu 《Science (New York, N.Y.)》1997,276(5313):788-790
Field observations and satellite geodesy indicate that little crustal shortening has occurred along the central to southern margin of the eastern Tibetan plateau since about 4 million years ago. Instead, central eastern Tibet has been nearly stationary relative to southeastern China, southeastern Tibet has rotated clockwise without major crustal shortening, and the crust along portions of the eastern plateau margin has been extended. Modeling suggests that these phenomena are the result of continental convergence where the lower crust is so weak that upper crustal deformation is decoupled from the motion of the underlying mantle. This model also predicts east-west extension on the high plateau without convective removal of Tibetan lithosphere and without eastward movement of the crust east of the plateau. 相似文献
26.
Evaluation of chlorophyll fluorescence as a tool for the identification of drought tolerance in upland cotton 总被引:1,自引:0,他引:1
Chlorophyll fluorescence (CF) is one tool used by researchers to quantify plant water status during periods of limited water availability. The research reported herein was designed to evaluate a CF-based protocol as a tool for use in cotton, Gossypium spp. breeding programs for the identification of drought tolerant genotypes. Twenty genotypes were selected to represent diverse and distinct US germplasm pools. Replicated tests were performed in Lubbock and College Station, TX in 2006 and 2007. Dryland and irrigated treatments, as main plots, were applied in a randomized complete block design, split to genotypes. CF measurements were taken at mid-bloom and late bloom growth stages. Source leaf tissue was harvested at predawn and subjected to high temperature incubation with CF measurements subsequently taken hourly for 5 h. Drought stressed plants had not mobilized their carbohydrate reserves from their source leaves overnight and thus maintained cell viability and therefore higher CF values throughout the incubation and measurement period with the opposite being true for non-stressed plants. Fiber lint yield and fiber properties were measured for comparison with the CF data. Genotype × treatment effects complicated the classification of genotypic response to drought. Few and inconsistent correlations were found among CF values and lint yield or fiber properties. Data suggested that this procedure provides little potential in selecting plants for drought tolerance when plants are grown under field culture. 相似文献
27.
The unique anatomic and physiologic characteristics of neonatal and pediatric patients make diagnosis, monitoring, and treatment a challenge.Adult parameters cannot be relied on in these patients, and an awareness of these unique characteristics is essential for any practitioner with a neonatal and pediatric patient base. In addition, many laboratory and pharmacologic data differ dramatically in neonates compared with adults of the same species.Familiarity with these variations is essential in the monitoring and treatment of the neonatal and pediatric illness, such as hypovolemia, shock, and sepsis. 相似文献
28.
29.
Raffaella Corsi DVM Maureen A. McMichael DVM DACVECC Stephanie A. Smith DVM MS DACVIM Mauria O'Brien DVM DACVECC Jennifer Herring DVM DACVECC Thandeka R. Ngwenyama DVM Alyssa Galligan CVT Alison N. Beloshapka MS Ping Deng MS Kelly S. Swanson PhD 《Journal of Veterinary Emergency and Critical Care》2014,24(3):259-263
30.