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The economic viability of the wildlife based enterprises (bee-keeping and caterpillar utilization) in Malawi is discussed in relation to conventional agricultural enterprises (maize, beans and ground-nuts). A strong incentive emerges for rural people to adopt wildlife management as an adjunct to subsistence agriculture, and therefore, to promote conservation of natural ecosystems and wildlife habitats in the face of growing human population and demand for land. Dependence on agriculture has depleted the wildlife resource outside protected areas and has been less effective in improving the wealth and living standards of most rural people. This study illustrates that the Malawi Department of National Parks and Wildlife needs to introduce economic incentives that integrate biological conservation with economic development for the rural people. The management programme involves the adoption of a rotation burning policy that promotes vegetation coppicing, eases harvesting and promotes high caterpillar yields. 相似文献
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Mark Andrews Alan Brown Jean-Yves Chiva David Fradet David Gordon Mark Lansdell Malcolm MacKenny 《Bioorganic & medicinal chemistry letters》2009,19(8):2329-2332
The reported selective serotonin Re-uptake Inhibitor Litoxetine was used as the starting point in the design of a range of potential SSRIs with high ease of synthetic accessibility. Preparation and subsequent optimization yielded a range of potent and highly selective SSRIs. 相似文献
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W. T. Brown 《American journal of human genetics》1996,58(5):903
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A Macintosh Hypertalk program (Hypercard stack)for use in phylogenetic comparative analysis of RNA structureis described. The program identifies covariations and compensatorychanges in RNA sequence alignments, for use in the constructionof secondary structure models or the identification of tertiaryinteractions. The results of an analysis are presented eitheras a list of positions in the alignment which covary, or asa 2-dimensional matrix in which potential helices in the secondarystructure appear as diagonal patterns.
Received on January 7, 1991; accepted on March 19, 1991 相似文献
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Regulatory and essential light-chain-binding sites in myosin heavy chain subfragment-1 mapped by site-directed mutagenesis 总被引:2,自引:0,他引:2
E J Mitchell J Karn D M Brown A Newman R Jakes J Kendrick-Jones 《Journal of molecular biology》1989,208(1):199-205
Site-directed mutagenesis of the cloned subfragment-1 (S-1) region of the unc-54 gene, encoding the myosin heavy chain B (MHC B) from Caenorhabditis elegans, has been used to locate binding sites for the regulatory and essential light chains. MHC B S-1 synthesized in Escherichia coli co-migrated with rabbit skeletal muscle myosin S-1 (Mr 90,000), was recognized by anti-nematode myosin antiserum on immunoblots, and specifically bound to 125I-labelled regulatory and essential light chains in a gel overlay assay. Deletion of 102 residues from the C terminus (mutant 655) reduced regulatory and essential light-chain binding to about 30% and 20% of wild-type levels, respectively. Similar reductions in relative binding of the two light chains were seen with mutant 534, in which 38 residues were deleted from the C terminus. Potential binding sites within 75 residues of the C terminus of S-1 were mapped by construction of five other mutant S-1 clones (398, 399, 400, 409 and 411) containing internal deletions of ten to 12 amino acid residues. These showed up to 30% reductions in their ability to bind essential light chains, but did not differ significantly from wild-type in their ability to bind regulatory light chains. Another mutant, 415, containing a deletion of a conserved acidic hexapeptide, E-D-I-R-D-E, showed enhancement of binding of regulatory and essential light chains to 150% and 165% of wild-type levels. Hence, the major binding sites for both light chains are within 38 amino acid residues of the C terminus. 相似文献
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