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由于现有的电子商务应用开发方法十分复杂,开发费用也十分高昂,对许多企业来说,要高效地开发可靠的电子商务应用是一个重要的挑战。而Web服务由于具有更简单的面向服务的结构以及更低的开发费用,越来越受到人们的欢迎。本文提出一种服务组合框架,通过这种框架可以采用基于Web服务的方法开发业务集成应用。通过考察Web服务的结构模型和电子商务的结构模式,我们认为本文所提出的框架能够组合用于电子商务应用的规范化Web服务,并且比现有的方法更加高效和可靠。  相似文献   
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This study was carried out to develop an evaluation method to predict rice seedling establishment (SE) under low-temperature conditions. Two Korean-bred japonica cultivars, Shindongjin and Hopum were used in the experiment. Fresh seeds were treated with an accelerated aging (AA) at 40°C and 100% RH for 1-15 days. The SEs of the fresh and AA seeds were evaluated in nursery beds at 17°C, and their correlation coefficients with seed vigor values measured by 9 test methods including standard germination test (SGT), cool germination test (CLT), cold germination test (CDT), seedling growth rate test (SGRT), ascorbate peroxidase (APX), peroxidase (POX), superoxide dismutase (SOD), catalase (CAT), and α ‐amylase (AMY) activities. The percentage of SE decreased slowly from 75 to 0% with an increasing of AA period from 0 to 15 days. The result of nine vigor tests showed different correlations with the SE. SGT, CLT, SGRT, and POX were significantly correlated with the SE. In the correlation analysis with only short-term aging seeds (1-7 days), the SE was very highly correlated with SGT, CLT, CDT, SGRT, POX, and CAT. These results suggest that seed vigor values measured by several methods including SGT and POX could be used as a reference value to secure SE at low temperatures in nursery bed rice seedling culture.  相似文献   
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This study examines the protective effects of gamma irradiation against postharvest insect damage and microbial contamination and its effect on the nutritive value of adlay (Coix lacryma-jobi L.). Adlay was treated with doses of 0–20 kGy gamma irradiation and subsequently stored at ambient temperature. The number of insects, microbial quality and chemical properties of irradiated and non-irradiated adlay were evaluated immediately after treatment and after 6 months of storage. Before irradiation, total aerobic microbial counts ranged from 5.6 × 102 to 1.4 × 105 CFU g−1 and the mean total number of insects was 3.2 ± 2.1 per 100 g of polished kernel. Two kilograys was the lowest dose that provided 100% insect control. A radiation-resistant bacterium, Deinococcus radiodurans RC1, was found in 2 of 10 adlay samples. Four kilograys was a sufficient dose for Enterobacteriaceae inactivation, and 6 kGy was a sufficient dose for yeast and fungi inactivation. Twenty and 8 kGy sufficed for the inactivation of all mesophilic microbes in samples with and without D. radiodurans, separately. Moreover the moisture, ash, crude fiber, crude fat, crude protein and riboflavin content all remained constant. However, 8 kGy irradiation reduced vitamin B1 concentration by 24.2%, but did not measurably reduce the amount of amino acids, except methionine and cysteine. Fatty acid contents did not alter after 8 kGy irradiation, but changes were observed after the 6 months of storage. These changes caused by irradiation were no greater than those caused by the 6-month storage. Irradiation up to 8 kGy did not markedly increase the acid value, but did increase the peroxide value to 13% of the initial value right after irradiation. However, significant changes in acid value and peroxide value were noted after 6 months of storage both in non-irradiated and post-irradiated storage samples. Additionally, 8 kGy irradiation did not significantly change the adlay appearance. The improvement in the hygiene of this vital food source compensates for the small loss of some nutritional constituents. Hence 8 kGy of gamma irradiation can be used in cold decontamination of adlay to prolong shelf-life, to improve postharvest quality, and to reduce the risk of food-borne disease.  相似文献   
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The Exploitation of Crop Allelopathy in Sustainable Agricultural Production   总被引:10,自引:0,他引:10  
Crop allelopathy may be useful to minimize serious problems in the present agricultural production such as environmental pollution, unsafe products, human health concerns, depletion of crop diversity, soil sickness and reduction of crop productivity. Several crops including alfalfa, buckwheat, maize, rice, rye, sorghum, sunflower, wheat, etc. are affected either by their own toxicity or phytotoxin exudates when their residues decompose in the soil, that show strong suppression on weed emergences. Allelopathic crops when used as cover crop, mulch, smother crops, green manures, or grown in rotational sequences are helpful in reducing noxious weeds and plant pathogen, improve soil quality and crop yield. Those crop plants, particularly the legumes, incorporated at 1–2 tons ha−1 (alfalfa, buckwheat, rice by-products), which can give weed reduction and increase of rice yield by 70 and 20 %, respectively, are suggested for use as natural herbicides. Allelochemicals from allelopathic crops may aid in the development of biological herbicides and pesticides. Cultivating a system with allelopathic crops plays an important role in the establishment of sustainable agriculture. The introduction of allelopathic traits from accessions with strong allelopathic potential to the target crops will enhance the efficacy of crop allelopathy in future agricultural production.  相似文献   
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Summary Interspecific hybrids have been obtained in an incompatible cross between Glycine max and G. tomentella through the in vitro culture of hybrid embryos. The percentage of successful pod setting in the crosses averaged 12.8% but there were marked differences depending on the soybean cultivar used as the female parent. Hybrid embryos at globular to heart stages were extracted from the embryo sac 15–25 days after pollination and cultured in vitro. Hybrid plants were successfully obtained by culturing the embryos on B5 medium supplemented with 0.1 mg/l IBA followed by culture on B5 medium supplemented with 0.1 mg/l TBA plus 0.25 mg/l 2-iP. The F1 plants resembled the wild male parent in growth form, but had an intermediate leaf shape between that of the parents.  相似文献   
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Peroxynitrite (ONOO(-)), formed from the reaction of superoxide (O(2)*(-)) and nitric oxide (*NO), is a cytotoxic species that can oxidize several cellular components such as proteins, lipids, and DNA. It has been implicated in diseases such as Alzheimer's disease, rheumatoid arthritis, cancer, and atherosclerosis. Due to the lack of endogenous enzymes responsible for ONOO(-) inactivation, developing a specific ONOO(-) scavenger is of considerable importance. The aim of this study was to evaluate the ability of marine natural products to scavenge ONOO(-) and to protect cells against ONOO(-). Methanolic extracts of 17 marine alga were tested for their ONOO(-) scavenging activity. Among them, Symphyocladia latiuscula showed the potent scavenging activity. CH(2)CH(2) fraction was partitioned with CH(2)CH(2) following n-hexanal extraction from the methanol extract of S. latiuscula. It was highly effective for ONOO(-) scavenging activity. Further analysis of the active fractionated extract identified 2,3,6-tribromo-4,5-dihydroxybenzyl methyl ether (TDB) as a potent ONOO(-) scavenger. The data demonstrated that TDB led to decreased ONOO(-)-mediated nitration of tyrosine through electron donation. TDB showed significant inhibition on nitration of bovine serum albumin and low-density lipoprotein by ONOO(-) in a dose-dependent manner. It also provided cytoprotection from cell damage induced by ONOO(-). TDB can be developed as an effective peroxynitrite scavenger for the prevention of the involved diseases.  相似文献   
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