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排序方式: 共有329条查询结果,搜索用时 15 毫秒
321.
L. R. BOOBAR M. R. SARDELIS J. H. NELSON W. M. BROWN 《Medical and veterinary entomology》1987,1(2):215-218
The newly designed Army Collapsible Insect Surveillance trap for nocturnal collection of flying Diptera that are attracted by light is described. A polyvinyl chloride construction increases durability, while the capability to collapse from a height of 92.1 cm to 24.1 cm facilitates transportation and storage. 相似文献
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MICHELLE HEGMON MATTHEW A. PEEPLES ANN P. KINZIG STEPHANIE KULOW CATHRYN M. MEEGAN MARGARET C. NELSON 《American anthropologist》2008,110(3):313-324
ABSTRACT Change is inevitable, but some changes and transformations are more dramatic and fraught with suffering than others. Resilience theory suggests the concept of a "rigidity trap" as an explanation for these differences. In rigidity traps, a high degree of connectivity and the suppression of innovation prolong an increasingly rigid state, with the result that the eventual transformation is harsh. Three archaeological cases from the U.S. Southwest (Mimbres, Mesa Verde, and Hohokam) and new methods for assessing transformations and rigidity are used to evaluate this concept. They reveal the expected association between the severity of transformation and degree of rigidity, suggesting that a rigidity trap contributed to the Hohokam decline, which included significant human suffering. Possible causes of rigidity, with implications for today's world, are explored. 相似文献
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THE water-soluble, cationic polymer diethylaminoethyl (DEAE) dextran, when added to many animal virus preparations, apparently facilitates the adsorption and penetration of viral particles into cells and thereby increases the titre. This has led to the suggestion1 that DEAE-dextran might usefully be incorporated into vaccines, at least those designed for veterinary use. This proposal has received considerable attention recently in the investigation of effective immunization procedures against foot and mouth disease2–5. We report here a series of experiments in which DEAE-dextran preparations were injected subcutaneously into mice and unexpectedly gave rise to fibrosarcomas at the site of injection. These results provide a warning that injection of vaccines containing DEAE-dextran may give rise to tumours in other species. 相似文献
325.
Charles Darwin's correspondence with David Moore of Glasnevin on insectivorous plants and potatoes 总被引:1,自引:0,他引:1
E. CHARLES NELSON F.L.S. MARK. R. D. SEAWARD F.L.S. 《Biological journal of the Linnean Society. Linnean Society of London》1981,15(2):157-164
Recently discovered correspondence between Charles Darwin and David Moore shows the latter's role in providing fresh material of importance to Darwin's studies on insectivorous plants. One letter relates to Moore's experimental work on potatoes. This research, probably concerned with resistance of selected varieties of potato to blight, is apparently not supported by Glasnevin Botanic Garden (Dublin) records or contemporary literature. 相似文献
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Effect of Mother's Dominance Rank on Offspring Temperament in Infant Rhesus Monkeys (Macaca mulatta)
BENJAMIN SUAREZ‐JIMENEZ AMANDA HATHAWAY CARLOS WATERS KELLI VAUGHAN STEPHEN J. SUOMI PAMELA L. NOBLE DANIEL S. PINE NATHAN A. FOX ERIC E. NELSON 《American journal of primatology》2013,75(1):65-73
In humans, temperament plays an important role in socialization and personality. Some temperaments, such as behavioral inhibition are associated with an increased risk for psychopathology. Nonhuman primates can serve as a model for neurobiological and developmental contributions to emotional development and several recent studies have begun to investigate temperament in nonhuman primates. In rhesus monkeys, dominance rank is inherited from the mother and is associated with social and emotional tendencies that resemble differences in temperament. The current study assessed differences in temperament in infant rhesus monkeys as a function of maternal dominance rank. Temperament was assessed in 26 infants (13 males) from birth until 6 months of age with a battery that included Brazelton test, human intruder test, human intruder‐startle, cortisol stress reactivity, and home cage observations of interactions with peers and the mother. Throughout testing, infants lived with their mothers and a small group of other monkeys in indoor/outdoor runs. Dominance rank of the mothers within each run was rated as either low/middle (N = 18, 9 male) or high/alpha (N = 8, 4 female). Infants of high‐ranking mothers displayed more intruder‐directed aggression and reduced startle potentiation in the human intruder tests. Dominant offspring also had reduced levels cortisol and startle across development and spent more time away from mothers in the interaction tests. These results suggest that dominance of the mother may be reflected in behavioral reactivity of infants early in life. These findings set up future studies, which may focus on contributing factors to both dominance and temperament such as genetics, rearing, and socialization. Such factors are likely to interact across development in meaningful ways. These results also suggest future human‐based studies of a similar relationship may be warranted, although social dominance is clearly more complex in human than macaque societies. Am. J. Primatol. 75:65‐73, 2013. Published 2012 by Wiley Periodicals, Inc.? 相似文献