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关键词： 质量作用域   出口   烟花爆竹检验   法理依据   运输区域   存储区域   销售使用区域  

摘要： 一、引言 烟花爆竹是涉及安全的产品,各国为了加强对其管理纷纷制定有关法律、法规、标准及条例(以下统称为国外技术法规)对其进行严格管理.这对保障烟花爆竹的安全生产、运输、储存、使用起到了积极的作用.但由于各国标准不尽相同,甚至存在某种程序的冲突,给出口烟花爆竹检验工作带来了许多难题.如主要输往美国的小礼花弹类产品,我国标准规定引线时间为8-12秒,而美国标准则规定为3-9秒,如果同时必须满足两国的标准,将此产品的引线时间定在8-9秒间,这在实际上是不可能做到的.

摘要： Motivation: We recently introduced a multivariate approach that selects a subset of predictive genes jointly for sample classification based on expression data. We tested the algorithm on colon and leukemia data sets. As an extension to our earlier work, we systematically examine the sensitivity, reproducibility and stability of gene selection/sample classification to the choice of parameters of the algorithm. Methods: Our approach combines a Genetic Algorithm (GA) and the k-Nearest Neighbor (KNN) method to identify genes that can jointly discriminate between different classes of samples (e.g. normal versus tumor). The GA/KNN method is a stochastic supervised pattern recognition method. The genes identified are subsequently used to classify independent test set samples. Results: The GA/KNN method is capable of selecting a subset of predictive genes from a large noisy data set for sample classification. It is a multivariate approach that can capture the correlated structure in the data. We find that for a given data set gene selection is highly repeatable in independent runs using the GA/KNN method. In general, however, gene selection may be less robust than classification.

关键词： discriminant partial least square model   back-propagation artificial neural network model   environmental soil sample  

摘要： Two variable selection methods were evaluated by comparing their predictions with respect to differentiating among environmental soil samples. The focus of this work is to determine which input variables are most relevant for prediction of soil sources using discriminant partial least square (D-PLS) and back-propagation artificial neural network (BP-ANN) models. The methods investigated were stepwise variable selection method and genetic algorithms (GAs). Microbial community DNA was extracted from 48 environmental soil samples derived, from different field crops and soil sources. After amplification of bacterial ribosomal RNA genes by polymerase chain reaction (PCR), the products were separated by gel electrophoresis. Characteristic complex band patterns were obtained, indicating high bacterial diversity. Two hundred and twenty-three, DNA band patterns produced in the gels of the soil samples were used in the analysis, after removal of included DNA standard markers. Based on the brightness of the bands, densitometric curves of the selected DNA band pattern were extracted from the gel images. The curves were smoothed using Savitsky-Golay method band scaled to the DNA standard markers. The prediction results based on the two variable selection methods for PLS and ANN models are presented and compared. Both methods gave good results before any variable selection methods, with the ANN being better than D-PLS. The prediction performance of both methods specially the D-PLS were improved by applying the stepwise variable selection and the GA variable selection method. The study also shows that GA variable selection had a significant improvement of the predictive ability than the stepwise variable selection method. (C) 2001 Elsevier Science B.V. All rights reserved.

关键词： O-acetyl groups   Liquid-chromatography   Gangliosides   Migration   Mucin  

摘要： Simultaneous analysis of sialic acids has been a challenging target, because sialic acids having N- or O-acetyl, glycolyl, and sulfonic acid ester groups are labile during their release from carbohydrate chains and analytical procedures. In the present paper, we propose a method using high-performance liquid chromatography coupled with eletrospray ionization mass spectrometry (HPLC-ESI-MS). The method was evaluated by applying to the analysis of sialic acids in various tissues, especially digestive organs in mice and rats. The method was based on the in situ precolumn derivatization of sialic acids after releasing them by hydrolysis. The sialic acids were derivatized with 1,2-diamino-4,5-methylenedioxybenzene to form highly fluorescent quinoxaline derivatives. By using two different hydrolysis conditions (i.e., with 2 M acetic acid and with 0. 1 M hydrochloric acid), both total sialic acids and sialic acid distributions were easily determined. We found that sialic acids showed characteristic distributions in the tissues of mice and rats. Further, HPLC-ESI-MS revealed that all the tissues examined in mice and rats commonly contained highly acetylated sialic acids and 8-O-sulfated N-acetylneuraminic acid.

关键词： CONTRACTS (International law)   INTERNATIONAL trade   EXPORT sales contracts   COMMERCIAL law  

摘要： Identifies the battle of the forms problem and the domestic solutions in the United States and Canada. Information on the battle of the forms problem; How to harmonize the contracts for the international sale of goods (CISG) with domestic laws; Discussion on the need for uniform interpretation of the CISG.

关键词： 现货交易   商业企业   合同的形式   口头合同   市场主体   义务关系   书面合同   合同管理   违约责任   理论指导实践  

摘要： 在市场经济条件下,作为市场主体的企业应该通过合同的形式来完成企业自身的权利、义务关系,在日常经济往来中,企业签订书面合同数量日渐减少。在调查中,有50％的企业基本上不签订购销合同,取而代之的是原始的现货交易,口头合同数量有增无减。长期以来,合同信誉制度,一直滞后于市场经济的发展,很多市场主体不愿签订书面合同。

关键词： .RPMI   amphotericin   dilution   uconazole   spp   Etest   Time–kill   Candida species   pre-exposure   synergy or antagonism   combinations against Candida  

摘要： Currently, there is considerable debate regarding the best in vitro method for testing anti- fungal combinations against Candida spp. In this study, we compared the results obtained by chequerboard dilution, time kill studies and Etest for several antifungal combinations against Candida spp. Three Candida albicans isolates (uconazole MICs of 1.0, 32 and >256 mg/L) and three non-albicans Candida isolates (C. glabrata, C. tropicalis and C. krusei) were tested in RPMI 1640 medium. By chequerboard testing, the majority of antifungal combinations were found to be indifferent. Notably, antagonism was identied by time kill studies and by Etest for combinations of amphotericin B uconazole, but it was not detected by the chequerboard method. Pre-exposure of isolates to uconazole did not affect results of the Etest or chequer- board method, but it did increase the frequency of antagonism noted by time kill methods. This study indicates that chequerboard dilution testing in RPMI medium may not reliably detect the attenuation of amphotericin B activity. Of the three methods, Etest was the simplest to use and yielded reproducible results for testing antifungal combinations.

关键词： Sound recording industry   MARKETING   Sound recordings  

摘要： Reports that Zomba Records Australia has entered a strategic service agreement with BMG Records Australia, to be effective in September, 2001. Operations as specified in the agreement, including on-ground sales and merchandising support for Zomba by the BMG sales team, and retail marketing and account management by Zomba; Speculation about the global market position of Zomba; Comments from executives in the industry about the agreement.

关键词： 临床医学   微生物检验   快速检报系统  

摘要： 临床微生物检验为了达到快速诊断的目的,就要落实快速检验和快速报告系统。分析起来该检报系统具有三个环节,每个环节有独特内容及其影响因素(见图解)。

关键词： 对外经贸   繁简   经济贸易关系   书面文件   contract   lease   加工贸易   confirmation   agency   劳务出口  

摘要： 对外经贸合同是我国经济实体与外国经济实体之间,在经济贸易关系方面规定相互间权利和义务的书面文件。按繁简程度的不同,合同可以采用以下几种书面形式: