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161.
LEE D. BAKER 《American anthropologist》2004,106(1):168-172
The Problem of Race in the Twenty-First Century. Thomas C. Holt. Cambridge, MA: Harvard University Press, 2002. 146 pp.
Race in Mind: Race, IQ, and Other Racisms. Alexander Alland Jr. New York: Palgrave Macmillan, 2002. 219 pp.
The Funding of Scientific Racism: Wickliffe Draper and the Pioneer Fund. William H. Tucker. Urbana: University of Illinois Press, 2002. 286 pp. 相似文献
Race in Mind: Race, IQ, and Other Racisms. Alexander Alland Jr. New York: Palgrave Macmillan, 2002. 219 pp.
The Funding of Scientific Racism: Wickliffe Draper and the Pioneer Fund. William H. Tucker. Urbana: University of Illinois Press, 2002. 286 pp. 相似文献
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DNA barcode (mitochondrial COI) sequences have allowed for species identification of aphids. In this study, we newly found a DNA barcoding problem in a part of the DNA sequences for Sitobion avenae. Five S. avenae individuals showed differences of, on average, 32.60% in the DNA sequences from other conspecific individuals, and a BLAST search revealed that the five sequences are similar to those of aphid parasitoids such as Aphidius, Ephedrus and Praon spp. (Hymenoptera: Braconidae). Based on these results, we concluded that the universal primers used in aphid DNA barcodes can amplify barcode sequences from parasitoid species within host aphids. 相似文献
170.
Sitona lineatus displays two distinct flight periods; a post-teneral flight in the late summer and a post-diapausal flight in the spring. The late summer flight begins as soon as adults start to emerge from pupal cells during late July and continues until mid-October. Maximum aerial density is observed in late August. Less than 10% of newly emerged adults leave the crop by flight, the rest remain in the soil or move to overwintering sites by walking. Spring flight begins in late March if temperatures are above the 12.5°C flight threshold and reaches a peak in mid-April. Most migratory flight is downwind. Little trivial flight occurs and once individuals have located a crop, redistribution is by walking. Laboratory studies indicate that adults fly most often during the day, particularly at noon. The size of infestations appeared to be independent of the area of legumes grown in a locality with large differences occurring even between neighbouring fields. Examination of the yields of field experiments at Rothamsted demonstrate an unexpected trend for higher yields in later sown spring bean crops. This may be because late sowing avoids infestation by spring migrants. 相似文献