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Lázaro-Lobo Adrián Ramirez-Reyes Carlos Lucardi Rima D. Ervin Gary N. 《Landscape Ecology》2021,36(12):3539-3555
Landscape Ecology - Invasive plants cause significant impacts in forested areas throughout the world. However, little is known about the relative importance of environmental drivers on the... 相似文献
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Multiphoton resonance ionization has been combined with energetic ion bombardment to examine dopant concentrations ofindium on the surface of silicon. The results yield a linear relation between the indium concentration and the known bulk values and a detection limit of 9 parts per trillion, at a mass resolution exceeding 160. This measurement, which surpasses the limits of any previous surface analysis by a factor of 100, has been made possible with an experimental configuration that optimizes sampling and detection efficiency while reducing background noise to virtually zero. During the analysis, submonolayer quantities of the surface are removed, so that as few as 180 surface atoms may be counted. 相似文献
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A L Komaroff M D Aronson T M Pass C T Ervin W T Branch J Schachter 《Science (New York, N.Y.)》1983,222(4626):927-929
In a study of 763 adult patients we found serologic evidence of infection (a fourfold increase in antibodies) with Chlamydia trachomatis in 20.5 percent of the patients and with Mycoplasma pneumoniae in 10.6 percent, but with group A streptococcus (by culture) in only 9.1 percent. Pharyngitis, the most common problem for which patients seek medical care in the United States, may be caused by nonviral, potentially treatable organisms more often than had been suspected. 相似文献
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Mirex, an organochlorine compound, was administered as a single oral dose (100 mg/kg body wt) to both intact and adrenalectomized juvenile male Sprague-Dawley rats. Both mirex-treated intact and adrenalectomized animals (dosed 24 hr postsurgery) exhibited significant increases in liver weight to body weight ratios compared to controls. However, the liver weight to body weight ratios in mirex-treated intact animals were significantly greater than those observed in mirextreated adrenalectomized animals. Significant increases were observed in liver weight to body weight ratios in adrenalectomized animals treated with mirex 4 days after surgery. However, the 96-hr mortality in mirex-treated adrenalectomized animals increased from 20% (mirex dose given 1 day postadrenalectomy) to 56% (mirex dose given 4 days postadrenalectomy). Mirex treatment of intact and adrenalectomized animals had no significant effect upon either serum or hepatic activities of glutamic oxalacetic transminase, glutamic pyruvic transaminase, sorbitol dehydrogenase, or protein concentrations. Bromsulfophthalein clearance also was not affected by mirex treatment in adrenalectomized animals. Serum glucose concentrations were significantly decreased in both intact and adrenalectomized animals by mirex treatment. Daily corticosterone supplements to adrenalectomized animals restored liver hypertrophy and serum glucose concentrations to levels observed in mirex-treated intact animals. These results suggest that mirex-induced liver enlargement may be mediated by corticosterone. 相似文献
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Two cues, either size or flavor of food pellet, were conditionally paired with either malaise induced by x-ray or pain induced by shock in four groups of rats. The combination of flavor and illness produced as conditioned decrement in consumption, but that of size and illness did not. Conversely, the combination of size and pain produced an inhibition of eating, but flavor and pain did not. Apparently, effective associative learning depends on central neural convergence of the paired afferent input. 相似文献
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Perceived land use patterns and landscape values 总被引：3，自引：0，他引：3
Ervin H. Zube 《Landscape Ecology》1987,1(1):37-45
Land use patterns and land form are important sources of information that contribute to the formation of landscape perceptions and values. This paper discusses three concepts of human-landscape relationships: the human as an agent of biological and physical impacts on the landscape; the human as a static receiver and processor of information from the landscape; and the human as an active participant in the landscape —thinking, feeling and acting — a transactional concept. A model of the transactional concept and of human perception and response is presented along with a conjectural example of human-landscape transactions. Three empirical research projects are presented to illustrate varying relationships between and among humans and landscapes. Variations in human experiences, needs and desires, personal utility functions for the use of the landscape, and socio-cultural contexts are suggested as mediating variables on perceived values and human responses. The importance of landscape values information to planning and management activities is discussed. 相似文献
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David R Shaw Amy B Asmus Jill Schroeder David E Ervin 《Pest management science》2023,79(12):4726-4730
Collaborative action on the part of all stakeholders in pest management is essential to effectively address the challenges of pesticide resistance. The US Environmental Protection Agency (EPA), through its Pesticide Program Dialogue Committee, recently posted a report on pesticide resistance management and the role the Agency can play in these efforts. In this Perspective, we commend the Agency for acknowledging these needs, and encourage implementation of the recommendations. We urge all stakeholders to follow the example set by the EPA to engage openly, listen to other stakeholders, and determine their role as part of the broader community that is needed to address the challenges of resistance. Our contention is that pesticide resistance will continue to escalate until all stakeholders evaluate their roles in resistance management and work together as a community to influence effective management. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献