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Virk S. S. Porter W. M. Li C. Rains G. C. Snider J. L. Whitaker J. R. 《Precision Agriculture》2021,22(3):777-799
Precision Agriculture - Maintaining adequate planter downforce is critical for achieving timely and uniform crop emergence across the field. On-farm research studies were conducted in different... 相似文献
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Toxicant-disease-environment interactions associated with suppression of immune system, growth, and reproduction 总被引:1,自引:0,他引:1
W P Porter R Hinsdill A Fairbrother L J Olson J Jaeger T Yuill S Bisgaard W G Hunter K Nolan 《Science (New York, N.Y.)》1984,224(4652):1014-1017
The effects of marginal malnourishment , infections, and environmental chemicals on growth and reproductive success in Swiss-Webster white mice and wild deer mice were studied with fractional factorial designs. Interaction effects were discovered. For example, malnourished mice were more sensitive to virus exposure and environmental chemicals (a plant growth regulator or polychlorinated biphenyls). Since several commercial plant growth regulators also appear to suppress the immune system, these results cast doubt on the adequacy of current toxicity testing procedures in which factors are studied individually and not in combination. 相似文献
477.
Light transmission through the body wall of living, color-labile desert iguanas (Dipsosaurus dorsalis) was measured by spectrophotometry. In the dark phase, the body wall's absorption of ultraviolet light and visible light was approximately twice that of the body wall in the light phase. The shorter wavelengths of ultraviolet could penetrate the body wall in the light phase but not in the dark phase. The intensity and wavelengths of light which could penetrate the body wall without pigments are potentially mutagenic when judged by bacterial standards. 相似文献
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Porter JR Chirinda N Felby C Olesen JE 《Science (New York, N.Y.)》2008,320(5882):1421-2; author reply 1421-2
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Woodley JD Chornesky EA Clifford PA Jackson JB Kaufman LS Knowlton N Lang JC Pearson MP Porter JW Rooney MC Rylaarsdam KW Tunnicliffe VJ Wahle CM Wulff JL Curtis AS Dallmeyer MD Jupp BP Koehl MA Neigel J Sides EM 《Science (New York, N.Y.)》1981,214(4522):749-755
Coral reefs of north Jamaica, normally sheltered, were severely damaged by Hurricane Allen, the strongest Caribbean hurricane of this century. Immediate studies were made at Discovery Bay, where reef populations were already known in some detail. Data are presented to show how damage varied with the position and orientation of the substraturn and with the shape, size, and mechanical properties of exposed organisms. Data collected over succeeding weeks showed striking differences in the ability of organisms to heal and survive. 相似文献
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