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91.
S Metcalfe A Hulands‐Nave M Bell C Kidd K Pasloske B O'Hagan N Perkins T Whittem 《Australian veterinary journal》2014,92(9):333-338
92.
John H. Perkins 《Agriculture and Human Values》1990,7(3-4):6-18
High yielding agriculture in less-industrialized countries, the green revolution, has been both honored and criticized over the past twenty years. Supporters point to the increased food supplies produced with the new practices, but detractors argue that the new technologies are environmentally destructive, unsustainable, and socially inequitable. This paper explores the origins of high yielding agriculture in order better to understand how the arguments over sustainability and equity originated. The Rockefeller Foundation was an important agency in promoting the development of the new agricultural science. Its programs in Mexico and India, initiated in 1941 and 1956, were key building blocks in creating high yielding agricultural practices. The Foundation scientists saw rapid population growth as the main source of hunger and communist subversion. In order to alleviate hunger and instability, they created a strategy of agricultural development based on increased yields but paid no attention to the problem of distribution of harvested food. Sustainability was not recognized as a problem at the time Foundation scientists began their work. Indeed the technical successes of their programs prompted the development of concerns about sustainability. Equity of distribution was brought to the attention of the Foundation before it began its work, but the scientists paid no attention to the issue. 相似文献
93.
Perkins PB 《Science (New York, N.Y.)》1917,46(1198):589-596
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95.
Morphologic studies of single crystals of aragonite within Codiacean algae reveal characteristic crystal forms produced by two distinctly different modes of calcification. Diagnostic serrated crystals (1 micrometer in length) of aragonite originating within the extracellular sheaths of capitular filaments are incorporated into modern lime sediments and may serve as effective tracers for particles of algal origin. Intracellular calcification within Penicillus dumetosus, previously unueported, is represented by doubly terminated aragonite crystals ranging in size from 48 to 160 micrometers. 相似文献
96.
Advanced technology paths to global climate stability: energy for a greenhouse planet 总被引:6,自引:0,他引:6
Hoffert MI Caldeira K Benford G Criswell DR Green C Herzog H Jain AK Kheshgi HS Lackner KS Lewis JS Lightfoot HD Manheimer W Mankins JC Mauel ME Perkins LJ Schlesinger ME Volk T Wigley TM 《Science (New York, N.Y.)》2002,298(5595):981-987
Stabilizing the carbon dioxide-induced component of climate change is an energy problem. Establishment of a course toward such stabilization will require the development within the coming decades of primary energy sources that do not emit carbon dioxide to the atmosphere, in addition to efforts to reduce end-use energy demand. Mid-century primary power requirements that are free of carbon dioxide emissions could be several times what we now derive from fossil fuels (approximately 10(13) watts), even with improvements in energy efficiency. Here we survey possible future energy sources, evaluated for their capability to supply massive amounts of carbon emission-free energy and for their potential for large-scale commercialization. Possible candidates for primary energy sources include terrestrial solar and wind energy, solar power satellites, biomass, nuclear fission, nuclear fusion, fission-fusion hybrids, and fossil fuels from which carbon has been sequestered. Non-primary power technologies that could contribute to climate stabilization include efficiency improvements, hydrogen production, storage and transport, superconducting global electric grids, and geoengineering. All of these approaches currently have severe deficiencies that limit their ability to stabilize global climate. We conclude that a broad range of intensive research and development is urgently needed to produce technological options that can allow both climate stabilization and economic development. 相似文献
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98.
A cDNA for a protein that interacts with the human immunodeficiency virus Tat transactivator 总被引:44,自引:0,他引:44
The human immunodeficiency virus (HIV) tat protein (Tat) is a positive regulator of virus gene expression and replication. Biotinylated Tat was used as a probe to screen a lambda gt11 fusion protein library, and a complementary DNA encoding a protein that interacts with Tat was cloned. Expression of this protein, designated TBP-1 (for Tat binding protein-1), was observed in a variety of cell lines, with expression being highest in human cells. TBP-1 was localized predominantly in the nucleus, which is consistent with the nuclear localization of Tat. In cotransfection experiments, expression of TBP-1 was able to specifically suppress Tat-mediated transactivation. The strategy described may be useful for direct identification and cloning of genes encoding proteins that associate with other proteins to modulate their activity in a positive or negative fashion. 相似文献
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