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331.
This publication presents an approach to assessing compositional equivalence between grain derived from glufosinate-tolerant rice grain, genetic event LLRICE62, and its nontransgenic counterpart. Rice was grown in the same manner as is common for commercial production, using either conventional weed control practices or glufosinate-ammonium herbicide. A two-season multisite trial design provided a robust data set to evaluate environmental effects between the sites. Statistical comparisons to test for equivalence were made between glufosinate-tolerant rice and a conventional counterpart variety. The key nutrients, carbohydrates, protein, iron, calcium, thiamin, riboflavin, and niacin, for which rice can be the principal dietary source, were investigated. The data demonstrate that rice containing the genetic locus LLRICE62 has the same nutritional value as its nontransgenic counterpart, and most results for nutritional components fall within the range of values reported for rice commodities in commerce.  相似文献   
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Cytosolic glutathione S-transferase (GSH transferase) activity towards 1-chloro-2,4-dinitrobenzene (CDNB) was elevated approximately three to four-fold in intestine and liver of mummichog (Fundulus heteroclitus) collected from a creosote-contaminated site in the Elizabeth River, Virginia. Intestinal GSH transferase activity at the most heavily contaminated site, at a moderately contaminated site and at a relatively clean site averaged 3.64, 2.83 and 1.11µmoles/min/mg respectively, while values for liver at these sites averaged 2.84, 1.75 and 0.93µmoles/min/mg. In addition, densitometric tracings of sodium dodecylsulfate-polyacrylamide gels of intestine and liver cytosol revealed a similar trend in the staining intensity of a 25.8 kD protein band, which lies within the molecular weight range of GSH transferase subunits. Activity in putative preneoplastic and neoplastic hepatic lesions of fish collected from the creosote-contaminated site was not significantly different from that of adjacent normal tissue. In the laboratory, dietary betanaphthoflavone (ßNF) treatment resulted in a three-fold increase in intestinal GSH transferase. Hepatic GSH transferase activity in the same fish was not affected by dietary ßNF although hepatic monooxygenase activity, measured as ethoxyresorufin O-deethylase (EROD), was. The results of this study indicate a response of the intestinal detoxification system to environmental contaminants and supports previous studies on the importance of intestinal metabolism of foreign compounds. Further, our results indicate the trend towards elevated GSH transferase in liver of feral fish could not be attributed to a cancerous disease state in these fish but indicates chemical induction in this organ as well.  相似文献   
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Abstract

Extensive forms of shrimp aquaculture have become an important source of income for farm households in the brackish water region of the Mekong Delta, Vietnam. The economic and production characteristics of farms are discussed in this paper, based on a 1997 farm survey, with particular emphasis on shrimp farming practices. Two types of shrimp fanning practice were observed, one based on natural recruitment of seedstock with few supplementary inputs, and the other based on relatively high cash investments in Penaeus monodon seedstock and other inputs. Households practising monodon culture made significantly more income, but faced high risk associated with shrimp mortality. An investigation of the factors affecting monodon yields indicated that investment in higher quality inputs had a positive effect on yield and income. However, further research is needed on the extent to which management can reduce risk of shrimp mortality by investing in such premium quality inputs.  相似文献   
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We used the portfolio method to examine how a forest company can lower investment risk by producing a mix of timber products. We derived optimum combinations of pine (Pinus patula) saw timber production and eucalypt (Eucalyptus grandis) pulpwood production at landscape level. Our results indicate that producing a product mix rather than a single product improves aggregated financial returns and lowers investment risk over multiple rotation periods. The optimum mixture depended on past timber price correlations for pulpwood and sawn timber in South Africa between 1980 and 2011. This ideal mixture is comprised of areal ratios of about 45% saw timber and 55% pulpwood. Our example shows how economic risk of a forest investment can be reduced by creating a portfolio of a number of products. The risk that an investor has to accept for each monetary unit that is expected in return can be reduced by over 40% when comparing the risk–return combinations of a pure pine saw-timber stand with that of a portfolio of forest products. The risk associated with the production can be reduced by 20% when growing a portfolio of products rather than eucalypt pulpwood only.  相似文献   
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This study was conducted in order to compare the nutrient and chemical contents of two Korean teas: traditional Chungtaejeon tea (CTJ) with that of green tea (GT). Main bioactive compounds and the antioxidant activities using four radical scavenging assays (ABTS, CUPRAC, FRAP and DPPH) in methanol and acetone extracts of both teas were determined. It was found that the contents of vitamin C, amino acids and total nitrogen in CTJ were lower than that of GT (p < 0.05). Caffeine, reducing sugar and chlorophyll contents in CTJ were similar to GT. Catechin (C), epicatechin (EC), and epigallocatechin (EGC) contents were lower in CTJ than in green tea (p < 0.05), but gallocatechin (GC), epicatechin gallate (ECG), epigallocatechin gallate (EGCG) and catechin gallate (CG) showed no significant differences between CTJ and GT (p ≥ 0.05). The contents of polyphenols, flavonoids, flavanols and tannins in CTJ methanol were 229.30 ± 11.3 mg GAE/g dry weight (DW), 15.24 ± 0.8 mg CE/g DW, 109.10 ± 5.1 mg CE/g DW and 25.68 ± 1.2 mg CE/g DW, respectively, and significantly higher than in acetone extracts (p < 0.05). Flavonoids (quercetin and kaempferol) were higher in GT than in CTJ and myricetin was higher in CTJ (p < 0.05). Threonine and aspartic acid was lower, and glutamic acid was higher in CTJ compared with GT (p < 0.05). Free amino acid content in CTJ and GT showed no significant difference. Potassium and magnesium in CTJ were lower compared to GT, but no significant difference was found for iron, manganese and calcium. Also, the level of the antioxidant activity by all four used assays was significantly higher in CTJ and in methanol was higher than in acetone extracts (p < 0.05). In conclusion, traditional fermented Korean tea Chungtaejeon contains high quantities of bioactive compounds and possesses high antioxidant activity. The contents of the bioactive compounds and the levels of antioxidant activities are significantly higher in methanol than in acetone extracts. 3-D fluorescence and FTIR- spectroscopy showed slight differences between the two investigated tea samples and can be used as additional tools for identification of polyphenols. Both studied teas can be recommended as a source of bioactive compounds.  相似文献   
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