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51.
52.
《Ethnic and racial studies》2012,35(3):501-507
ABSTRACTThis comment argues that scholars have been too quick to dismiss Confucian culture as an explanation for the exceptional educational attainment of second generation Asian Americans. It shows that, for centuries, all classes in Confucian societies perceived education as the engine of upward mobility, not merely elites. For this reason, the children of working class Chinese and Japanese immigrants outperformed whites already before World War II. Furthermore, the educational outcomes of non-Confucian Asian Americans turn out to be unexceptional after their family backgrounds are taken into account. Thus, to the extent that Asian American schooling levels are unusual, it seems premature to attribute that achievement to class culture rather than mass culture. 相似文献
53.
《Ethnic and racial studies》2012,35(6):988-1006
Abstract This article examines how South Asian American communities ascribe meaning to the category of ‘race’ while adding their own sensibilities to racial categories of ‘black’ and ‘white’. Drawing upon ethnographic methods, I analyse leisure spaces of basketball to demonstrate how racial formation in the US for non-white ethnic American subjects engages the black–white racial binary while simultaneously critiquing this racial logic. Racial categories provide a lexicon for comprehending South Asian American difference, while South Asian idioms perpetuate racializing discourses. 相似文献
54.
Hong Zhu 《Biocontrol Science and Technology》2012,22(4):393-406
Dissemination of microbial biocontrol agents via predators may have advantages for safe spore dispersal to targeted pests with the added benefit of predation. A laboratory study was conducted to test the target-oriented dissemination of conidia of Beauveria bassiana using larvae of both the multicoloured Asian lady beetle (Harmonia axyridis) and common green lacewing (Chrysoperla carnea) for control of aphids. Maximum dry conidial attachment occurred within approximately 7 min after exposure. After release of the treated predators on leaves of Chinese cabbage, within 12 hours lacewing larvae dispersed 89% of the attached conidia while Asian lady beetles dispersed 93%. Both predators dispersed conidia up to 2.4 m from the release site. Leaf disk bioassays were conducted to compare two application methods; the dissemination of conidia of B. bassiana by predators and the direct application of conidial suspensions. Mortality in sprayed aphids was 91±2.1% compared to 88±2.1 and 84±4.2%, respectively, when conidia were disseminated by lacewings and lady beetles. Predation was not affected in treated lacewing larvae whereas there was a 20% reduction in predation by lady beetle larvae. It appears that B. bassiana can be effectively delivered using certain insect predators. 相似文献
55.
PHILLIP Q. SPINKS ROBERT C. THOMSON BILL HUGHES BRAD MOXLEY RAFE BROWN ARVIN DIESMOS H. BRADLEY SHAFFER 《Zoological Journal of the Linnean Society》2012,164(4):811-824
Loss of habitat and human exploitation have driven many turtle species to the brink of extinction, particularly in many parts of southern Asia. The spiny turtle (Heosemys spinosa) is a terrestrial species distributed throughout the Sundaland region of South‐East Asia. Despite international legislative protection, H. spinosa continues to be illegally collected for the food and traditional medicine markets of China. Given its widespread distribution, taxonomists have reasonably questioned whether H. spinosa truly represents a single evolutionary lineage or multiple undiagnosed species. Recently, a large and illegal shipment of rare, wild‐caught H. spinosa was confiscated in Hong Kong, China, and the turtles were eventually distributed to several zoos and academic collections. Based on analyses of these individuals, along with additional individuals from the pet trade and museum collections, we found concordant genetic and phenotypic variation, indicating that two distinct types of H. spinosa exist in this collection of turtles. Further characterization of this variation will require field surveys and the collection of additional morphological and genetic data from specimens of known geographic provenance. However, our data indicate that this highly exploited, endangered species may contain additional cryptic taxa, and emphasize the critical need for systematic evaluation of species before unrecognized variation is lost forever. © 2012 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 164 , 811–824. 相似文献
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57.
The "Other" Story of Model Minorities: Korean American High School Dropouts in an Urban Context 总被引:1,自引:0,他引:1
JAMIE LEW 《Anthropology & education quarterly》2004,35(3):303-323
This article analyzes how socioeconomic backgrounds, social capital, and school resources affect Korean American youths' educational attainment and aspirations. In the context of limited social and economic support, students delineate differences within coethnic communities along class lines and adopt an oppositional cultural frame of reference to endure and resist institutional barriers. This study demonstrates the significance of distinguishing socioeconomic differences within Korean American communities and for whom the enclaves may be more beneficial. 相似文献
58.
Use of 50 × 500 mm non-woven fiber bands impregnated with cultures of entomopathogenic fungi was investigated for control of Anoplophora glabripennis. Fungal bands produced as a commercial pest control product and obtained from industry contained Beauveria brongniartii NBL 851 while lab-produced bands contained B. brongniartii WU 20 or Metarhizium anisopliae VD 1. In the laboratory, adult longevity decreased when adult A. glabripennis were forced to walk for 5 s on bands impregnated with B. brongniartii NBL 851 and for 25 s on B. brongniartii WU 20 and M. anisopliae VD 1 bands. A field experiment was conducted over a 31-day period in Huaiyuan, Anhui, China, by attaching bands impregnated with B. brongniartii NBL 851 or WU 20 around the trunks of willows (Salix sp.) at two sites infested with A. glabripennis. Treatments were compared directly, by monitoring adult longevity, and indirectly, by counting oviposition scars and exit holes per tree to quantify relative oviposition per female. Adults collected from trees treated with B. brongniartii WU 20 died more quickly than adults from the trees treated with B. brongniartii NBL 851 or controls. At the site with higher A. glabripennis population densities, relative oviposition per female was significantly lower for both fungal treatments compared with the control treatment. Between fungal treatments, B. brongniartii NBL 851 had a 5 day earlier negative effect on oviposition per female than B. brongniartii WU 20. 相似文献
59.
Asian elephants (Elephas maximus) are an endangered species. Their future survival depends on intensive conservation and management, based on in‐depth knowledge of particular populations. Molecular genetic methods, especially microsatellite analysis through noninvasive sampling, provides an effective means of obtaining such information. The use of tri‐ and tetranucleotide microsatellite markers is advantageous in noninvasive sampling through dung analysis. Here we describe the isolation and characterization of five tri‐ and tetranucleotide markers in the Asian elephant. All five loci were found to be polymorphic in a sample of 20 Asian elephants from Sri Lanka. 相似文献
60.
东亚与北美大羽羊齿植物间的主要差异在于蕨叶的结构:北美大羽羊齿植物的蕨叶为单叶或二歧分叉叶,而东亚的大羽羊齿植物以往只知为羽状复叶或不分叉的单叶,因之,二歧分叉蕨叶在中国的发现具有十分重要的意义,它使东亚与北美大羽羊齿植物之间的关系变得更为密切,虽然其间仍存在不实质性的差异,同时,对东亚和北美华夏羊齿Cathaysiopteris之间的异同作了较详的讨论。 相似文献