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241.
Deaths attributed to ingestion of Nicotiana glauca are extremely rare. We report here a case where a 43-year-old man was found dead after apparently drinking a water extract of Nicotiana glauca. The primary alkaloid in the plant is anabasine. Toxicological analysis by capillary gas chromatography showed the deceased had a blood anabasine concentration of 2.2 mg/L. Clinically, the features of poisoning are nicotine-like and if death occurs it results from respiratory paralysis. The case further supports the view that, in the human, anabasine is considerably more toxic than nicotine. 相似文献
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One consequence of the drug war has been the incarceration of many offenders who pose a health risk to staff. This article presents an analytical framework to examine the factors that influence staffs' perceptions of the threat of infection. Four risk domains influence an officer's self-rated threat of exposure: (1) psychosocial factors, (2) HIV/AIDS-related knowledge, (3) perception of risk in the prison environment, and (4) risk reduction efforts. Officers with lower levels of education, those who worked with medium and maximum custody inmates, and those who had more high-risk encounters with inmates rated their chances for infection as high. Findings are discussed in light of their practical and theoretical applications. 相似文献
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Biochar currently attracts technological and market optimism, promising multiple wins – for climate change, food security, bioenergy and health – not least for African farmers. This paper examines the political-economic and discursive processes constructing biochar as a novel green commodity, creating new alliances amongst scientists, businesses, venture capital firms and non-governmental organisations. Carbon market logics are not only threatening large-scale land grabs for biochar feedstocks but also other forms of resource, labour and ecological appropriation through driving research and development and shaping small-scale pilot projects. In these, soil carbon is ‘chopped out’ of its ecosystem and social contexts and revalued as exchangeable pieces of carbon nature. Farmers are hailed as green actors and market winners, provided they discipline their practices according to these new technical and market logics. These discourses contrast strongly with the farmers' existing conceptual and practical repertoires; a case study from Liberia illustrates how farmers already manipulate soil carbon in creating locally valued anthropogenic dark earths, but within diverse farming repertoires, ontologies of human–nature interrelationship and historical and political ecologies. 相似文献
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