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Discussions of the scope and proper definition of anthropology make it worthwhile to outline why and how anthropology can be treated as a natural (and exact) science. The paper describes its multidisciplinary components and how the deterministic properties of biological individuality and the probabilistic constraints of the cultural dimensions can be brought together. Such a synthesis enables us to treat values within a biological framework and suggests the old term "humanics" for the multidisciplinary nexus . [anthropological biology, humanics, multidisciplinary synthesis, interaction measurement, behavioral biology]  相似文献   
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To analyze the synthesis, structure and function of the plant cell wall by a genetic approach, 5200 chemically mutagenized Arabidopsis plants were screened for changes in the monosaccharide composition of hydrolyzed cell wall material by gas chromatography of alditol acetates. This screening procedure identified 23 mutant lines representing 11 different loci designated mur1 to mur11 . The mur lines fall into essentially three groups: (1) complete absence of a monosaccharide, (2) significant reduction in the amount of a single monosaccharide, and (3) complex alterations in the relative amounts of several monosaccharides. All mutants in the first category represent alleles of the mur1 locus, and are deficient in the de novo synthesis of fucose. Mutants with reductions in a single monosaccharide have been identified for fucose ( mur2, mur3 ), arabinose ( mur4, mur5, mur6, mur7 ), and rhamnose ( mur8 ). Mutants with complex changes in monosaccharide composition are represented by the mur9 , mur10 and mur11 loci. Most of the mutant lines did not show obvious morphological or physiological alterations; however, lines mur1, mur9 and mur10 co-segregated with reduced vigor or dwarfism of the plants. These results demonstrate the feasibility of identifying plants with altered cell wall compositions via a biochemical screening procedure. The availability of these mutants provides novel opportunities to study the functions of cell wall polysaccharides, gain insight into the biosynthesis of cell wall material, and clone cell wall-related genes.  相似文献   
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Follow-up of 108 opiate addicts for a period of six to seven years showed that 35 were still being prescribed opiates, 25 were off drugs, 19 were dead, and for 29 it was not certain whether they were on or off drugs. Most patients who came off drugs did so in the first two years after notification to the Home Office. Clearly treatment is more likely to be successful if given early in the life history of the addict, when it is appropriate to give treatment based on withdrawal of drugs rather than substitution.  相似文献   
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In order to aid the integration of biological and chemical controls for the tomato leaf miner, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), this study evaluated the relative toxicity of five insecticides to the leaf miner predator Macrolophus basicornis (Stal) (Hemiptera: Miridae). The insecticides evaluated were teflubenzuron, abamectin, chlorantraniliprole, chlorfenapyr, and cartap hydrochloride, all of which are recommended for control of T. absoluta in Brazil. Nymphs and adults of M. basicornis were exposed to tomato leaves treated with the insecticides, under laboratory and greenhouse conditions. The overall mortality caused by the products in both situations was recorded, and the survival of congeneric groups was analysed using the Weibull model. The persistence of the insecticides was also evaluated and they were categorised into toxicity classes proposed by the International Organisation for Biological Control (IOBC) based on predator mortality and persistence. Abamectin and chlorfenapyr were toxic to M. basicornis nymphs and adults in all bioassays. Cartap hydrochloride was slightly harmful to adults in laboratory assays, but harmful to nymphs, and moderately harmful under greenhouse conditions. Chlorantraniliprole and teflubenzuron were harmless in most assays, except when nymphs were exposed in the laboratory, where they were moderately and slightly harmful, respectively. Chlorantraniliprole and teflubenzuron should be preferred insecticides for use in tomato leaf miner IPM programmes that aim to conserve M. basicornis populations.  相似文献   
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