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111.
Kimberly G. Nugent Barry J. Saville 《Forensic Science International Supplement Series》2004,140(2-3):147-157
Hallucinogenic fungi synthesize two controlled substances, psilocin and psilocybin. Possession of the fungal species that contain these compounds is a criminal offence in North America. Some related species that are morphologically similar, do not contain the controlled substances. Therefore, unambiguous identification of fungi to the species level is critical in determining if a mushroom is illegal. We investigate a phylogenetic approach for the identification of species that contain the psychoactive compounds. We analyzed 35 North American specimens representing seven different genera of hallucinogenic and non-hallucinogenic mushrooms. We amplified and sequenced the internal transcribed spacer region of the rDNA (ITS-1) and a 5′ portion of the nuclear large ribosomal subunit of rRNA (nLSU rRNA or 28S). ITS-1 locus sequence data was highly variable and produced a phylogenetic resolution that was not consistent with morphological identifications. In contrast, the nLSU rRNA data clustered isolates from the same species and separated hallucinogen containing and non-hallucinogen containing isolates into distinct clades. With this information, we propose an approach that combines the specificity of PCR detection and the resolving power of phylogenetic analysis to efficiently and unambiguously identify hallucinogenic fungal specimens for legal purposes. 相似文献
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The NSF engineering research centers (ERC) program served notice of a sea change in university research funding and institutional designs, representing a transition from department-based, principle investigator-oriented university science to a new center-based model encouraging universities to work with industry and to work beyond the strictures of academic disciplines. In our view, the past three decades of U.S. science and technology policy have not seen an institutional change of greater importance. This paper begins with a brief history of the ERC program, including discussion of the program’s origins, goals and research foci, growth, and influence as a model for other science center programs in the U.S. and abroad. Our “primary data” include an interview with Erich Bloch, former NSF director who was one of the chief architects and advocates for the ERC program. Because of the historical importance of this interview, we present the entire interview with the original material largely unaltered. We conclude with discussion of the managerial challenges that ERCs face within the context of traditional university structures. 相似文献
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Two American economists discuss in considerable detail the critical problem of interenterprise arrears (overdue payments for goods and services) in Russia that undermines the transition to a market economy and privatization. The study is based on interviews involving directors of 32 industrial enterprises, managers of commercial banks, and Central Bank officials in Moscow, Novosibirsk and Sochi from May to mid-November 1992. In addition to analyzing the causes of the mounting accumulation of debt and highlighting the financial problems of enterprises coping with the crisis, the authors examine the anatomy of present-day banking and extension of credit to finance production in the former USSR. Journal of Economic Literature, Classification Numbers: P21, Ol7, G20. 相似文献