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MERRILL SINGER HASSAN SALAHEEN GREG MIRHEJ CLAUDIA SANTELICE 《American anthropologist》2006,108(3):502-506
In this research report, we present findings on drinking among drug users from a larger multimethod study of the public health consequences of emergent, changing, and understudied drug-related behavioral patterns among street drug users in Hartford, CT. Although drinking and illicit drug use traditionally have been studied in anthropology as separate cultural domains, this conceptual division has hindered examination of the significant level of drinking among street drug users, the motivations for heavy drinking in this population, and the public health consequences of mixing alcohol and other drugs, including drug relapse. 相似文献
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MERRILL SINGER 《American anthropologist》2006,108(2):443-444
A Rainbow of Gangs: Street Cultures of the Mega-City . James Diego Vigil. Austin: University of Texas Press, 2002. 213 pp. 相似文献
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The pollination biology of Sauroglossum elatum Lindl. (Orchidaceae: Spiranthinae): moth-pollination and protandry in neotropical Spiranthinae 总被引:1,自引:0,他引:1
RODRIGO B. SINGER 《Botanical journal of the Linnean Society. Linnean Society of London》2002,138(1):9-16
The pollination biology of Sauroglossum elatum Lindl (Orchidaceae: Spiranthinae) was studied in the State of São Paulo, south-eastern Brazil. This orchid is protandrous and almost fully self-compatible, but pollinator-dependent. Thus, pollinators are required for the plants to set fruits and seeds. The flowers are pollinated by moths of the family Noctuidae. Pollinia are dislodged when the moths probe flowers in the male phase. At this stage the stigmatic surface is inaccessible, so that the flowers can act only as pollen-donors. Flowers in the female phase present their stigmatic surfaces well exposed and dry viscidia; at this stage the flowers act as pollen receivers. Pollinarium-bearing moths, when visiting a flower in the female phase, will brush the pollinarium against the stigmatic surface, thus effecting the pollination. Moth-pollination is reported here for the first time for the orchid subtribe Spiranthinae. Protandry also occurs in a few additional Brazilian Spiranthinae. Based on the evidence presented in this work, protandry in Spiranthinae is not necessarily linked to bumblebee pollination, as currently accepted. It is suggested that the occurrence of protandry in Spiranthinae and in the closely related subtribes Prescottinae and Goodyerinae may also be a feature encompassing ecological and phylogenetic implications. Anecdotal ex-situ observations are briefly discussed. Cultivated specimens were actively visited by Tetragonisca angustula (Meliponini) bees. which broke the pollinaria, collected the pollen and eventually performed pollination by leaving small fragments of the pollinia on the stigmatic surface. © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 138 , 9–16. 相似文献
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