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31.
Biotechnology applications such as the use and production of genetically modified organisms (GMOs) have been widely promoted, adopted, and employed by agricultural producers throughout the world. Yet, little research exists that examines the implications of agricultural biotechnology on the health and safety of workers involved in agricultural production and processing. Regulatory frameworks do exist to examine key issues related to food safety and environmental protection in GMO applications. However, based on the lack of research and regulatory oversight, it would appear that the potential impact on the safety and health of workers is of limited interest. This article examines some of the known worker health and safety implications related to the use and production of GMOs using the host, agent, and environment framework. The characteristics of employers, workers, inputs, production practices, and socio-economic environments in which future agricultural workers perform various tasks is likely to change based on the research summarized here. 相似文献
32.
Genetic engineering of novel genomes of large DNA viruses 总被引:15,自引:0,他引:15
Analyses of the function of specific genes and sequences of large DNA viruses such as herpesviruses and poxviruses present special problems because of the size of their genomes (120 to 250 kilobase pairs). Various methods for engineering site-specific insertions or deletions based on the use of selectable markers have been developed and applied for the elucidation of the function of specific DNA sequences, the identification of genes nonessential for virus growth in cell culture, and the expression of foreign genes. These methods should also make possible the construction of viral vectors capable of delivering genes specifying antigens for the prevention of infectious diseases in humans and animals. 相似文献
33.
Chimpanzee bipedalism: cineradiographic analysis and implications for the evolution of gait 总被引:2,自引:0,他引:2
F A Jenkins 《Science (New York, N.Y.)》1972,178(63):877-879
Bipedal chimpanzees reorient the pelvis to achieve an upright posture but retain the same pattern of femoral flexion and extension as in quadrupedal walking. Major differences from human gait are the abducted, relatively more flexed excursion of the femur and the timing of pelvic tilt, which raises during the swing phase. The femoral head morphology in the fossil hominid Australopithecus robustus is evidence of an approximately vertical excursion of the femur in contrast to the adducted pattern of modern man and the abducted pattern of chimpanzees. 相似文献
34.
Nadeau JH Balling R Barsh G Beier D Brown SD Bucan M Camper S Carlson G Copeland N Eppig J Fletcher C Frankel WN Ganten D Goldowitz D Goodnow C Guenet JL Hicks G Hrabe de Angelis M Jackson I Jacob HJ Jenkins N Johnson D Justice M Kay S Kingsley D Lehrach H Magnuson T Meisler M Poustka A Rinchik EM Rossant J Russell LB Schimenti J Shiroishi T Skarnes WC Soriano P Stanford W Takahashi JS Wurst W Zimmer A;International Mouse Mutagenesis Consortium 《Science (New York, N.Y.)》2001,291(5507):1251-1255
35.
High-speed x-ray movies of European starlings flying in a wind tunnel provide detailed documentation of avian skeletal movements during flapping flight. The U-shaped furcula (or "wishbone," which represents the fused clavicles) bends laterally during downstroke and recoils during upstroke; these movements may facilitate inflation and deflation of the clavicular air sac. Sternal movements are also coupled with wingbeat, ascending and retracting on downstroke and descending and protracting on upstroke in an approximately elliptical pathway. The coupled actions of the sternum and furcula appear to be part of a respiratory cycling mechanism between the lungs and air sacs. 相似文献
36.
Thermal diffusivity and specific heat have been measured by the flash method on a small specimen of meteoritic iron from the Canyon Diablo fall. Measurements have been made over the temperature range -150 degrees to 300 degrees C from which thermal conductivity values have been calculated. 相似文献
37.
Jenkins WJ 《Science (New York, N.Y.)》1977,196(4287):291-292
The newly developed technique of "tritium-helium dating" has been used to investigate in situ rates of oceanic oxygen utilization. As an example, an apparent oxygen utilization rate of 0.20 +/- 0.02 milliliter per liter of water per year has been obtained for the Subtropical Mode water (18 degrees C water) in the Sargasso Sea. 相似文献
38.
39.
Kennett JP Houtz RE Andrews PB Edwards AR Gostin VA Hajos M Hampton MA Jenkins DG Margolis SV Ovenshine AT Perch-Nielsen K 《Science (New York, N.Y.)》1974,186(4159):144-147
Deep-sea drilling in the Southern Ocean south of Australia and New Zealand shows that the Circum-Antarctic Current developed about 30 million years ago in the middle to late Oligocene when final separation occurred between Antarctica and the continental South Tasman Rise. Australia had commenced drifting northward from Antarctica 20 million years before this. 相似文献
40.