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Brashares JS Arcese P Sam MK Coppolillo PB Sinclair AR Balmford A 《Science (New York, N.Y.)》2004,306(5699):1180-1183
The multibillion-dollar trade in bushmeat is among the most immediate threats to the persistence of tropical vertebrates, but our understanding of its underlying drivers and effects on human welfare is limited by a lack of empirical data. We used 30 years of data from Ghana to link mammal declines to the bushmeat trade and to spatial and temporal changes in the availability of fish. We show that years of poor fish supply coincided with increased hunting in nature reserves and sharp declines in biomass of 41 wildlife species. Local market data provide evidence of a direct link between fish supply and subsequent bushmeat demand in villages and show bushmeat's role as a dietary staple in the region. Our results emphasize the urgent need to develop cheap protein alternatives to bushmeat and to improve fisheries management by foreign and domestic fleets to avert extinctions of tropical wildlife. 相似文献
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Valentine S Moses Alicia L Bertone 《Veterinary Clinics of North America: Equine Practice》2002,18(1):21-37, v
Nonsteroidal anti-inflammatory drugs (NSAIDs) are substances other than steroids that inhibit a component of the inflammatory cascade. This article is dedicated to those substances which specifically inhibit cyclooxygenase. NSAIDs are used extensively in the veterinary field. This article discusses their pharmacologic mechanism of action, indications, and toxicity. The two isoforms of cyclooxygenase (COX-1 and COX-2) are reviewed along with the newer NSAID which are more effective and less toxic due to more specific COX-2 inhibition. Specific effects on soft tissue, bone, cartilage, and synovium are summarized. Pain modulation is extensively reviewed as well as the antiendotoxic and antithrombotic uses. 相似文献
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J. A. Manu-Aduening R. I. Lamboll G. Ampong Mensah J. N. Lamptey E. Moses A. A. Dankyi R W. Gibson 《Euphytica》2006,150(1-2):47-61
Summary A participatory breeding programme involving farmers in two Ghanaian communities and scientists from CRI (Ghana) and NRI (UK) to develop superior cassava cultivars is described. Initial situation analyses of the communities indicated that cassava is increasing in importance both as a food and a cash crop. Most farmers utilised landraces of cassava; modern varieties were scarcely mentioned. Seeds of 16 half-sib families obtained from a crossing block in Nigeria at the International Institute of Tropical Agriculture were planted in a field in each community. During seedling and subsequent clonal generations, accessions selected either by farmers or scientists were retained to the next generation. This selection process has identified 29 superior accessions from amongst 1350 original seedlings. Farmers were relatively consistent in their selection from year to year and their selections corresponded with their stated criteria. Official variety release requires additional multilocational and inspection trials and postharvest assays but otherwise seems harmonious with a participatory breeding approach; our early involvement of farmers may facilitate early release, an important factor in cost-effectiveness. A stakeholder workshop confirmed the need for improved markets for cassava; surveys of current and potential markets have led to field trials with cassava processors. Adoption of a participatory approach, with farmers and scientists taking on new roles and decentralisation of activities, implies a concomitant transfer of influence and resources. 相似文献
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Moses T.K. Kairo Gene V. Pollard Dorothy D. Peterkin Vyjayanthi F. Lopez 《Integrated Pest Management Reviews》2000,5(4):241-254
The hibiscus mealybug, Maconellicoccus hirsutus Green, was first reported in the Caribbean in 1994 in Grenada. This was the first record of the insect as a major pest in the New World. By the beginning of 2001, the pest had spread to over 25 territories from Guyana and Venezuela in the South to Bahamas in the North. The pest has also extended its distribution to Central America (Belize) and North America (California, USA). Early attempts to control the pest using pesticides resulted in failure and a classical biological control approach was adopted. Several exotic natural enemies were introduced but control was attributed to Anagyrus kamali Moursi and Cryptolaemus montrouzieri Mulsant. In all countries where biological control was implemented, this resulted in success. This paper reviews the remarkable success story. Information is provided on the distribution and factors leading to rapid spread of the pest, its pest status and resultant economic losses, and implementation of the biological control effort. 相似文献
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The [As@Ni12@As20]3- ion was prepared from As7(3-) and Ni(COD)2 in ethylenediamine solutions and isolated as the Bu4P+ salt (As, arsenic; Ni, nickel; COD, cyclooctadiene; Bu, butyl; P, phosphorus). The anion contains an icosahedral [Ni12(mu12-As)]3- fragment that resides at the center of an As20 dodecahedral (fullerene) cage to give an onion-skin-like [As@Ni12@As20]3- cluster with Ih point symmetry. The icosahedron and pentagonal dodecahedron are reciprocal platonic solids, and the 32 surface atoms form a dimpled geodesic sphere composed of 60 triangular faces. In the gas phase, the [As@Ni12@As20]3- ion sequentially loses all 21 As atoms to form a series of Ni12As(21-x) clusters where 0 = x = 21, inclusively. 相似文献
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