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关键词： 非处方药   企业   企业管理   药品分类管理   药品监督管理   包装  

关键词： DSC   thermal denaturation   vegetative bacteria  

摘要： Thermal stability of vegetative cells of Listeria monocytogenes, Escherichia coli and Lactobacillus plantarum was studied by counting viable fractions and determining DSC curves of their suspensions. DSC curves in the 5-99 degrees C range showed a series of endothermic transitions between 50 and 60 degrees C, where the heat destruction of cells occurred. Heat denaturation of DNA required a higher temperature than cell killing. Thermal death was strongly influenced by the pH, composition and NaCl content of the suspending buffer. A mathematical model developed by us enabled comparison of DSC peak temperatures and temperatures required for loss of viability.

关键词： 贷款   放款   违约处理   商业银行风险   监督  

摘要： In many real-world learning tasks it is expensive to acquire a sufficient number of labeled examples for training. This paper investigates methods for reducing annotation cost by sample selection. In this approach, during training the learning program examines many unlabeled examples and selects for labeling only those that are most informative at each stage. This avoids redundantly labeling examples that contribute little new information. Our work follows on previous research on Query By Committee, and extends the committee-based paradigm to the context of probabilistic classification. We describe a family of empirical methods for committee-based sample selection in probabilistic classification models, which evaluate the informativeness of an example by measuring the degree of disagreement between several model variants. These variants (the committee) are drawn randomly from a probability distribution conditioned by the training set labeled so far. The method was applied to the real-world natural language processing task of stochastic part-of-speech tagging. We find that all variants of the method achieve a significant reduction in annotation cost, although their computational efficiency differs. In particular, the simplest variant, a two member committee with no parameters to tune, gives excellent results. We also show that sample selection yields a significant reduction in the size of the model used by the tagger.

摘要： 20年前真理标准问题的讨论不仅具有重大的实践意义，而且具有重大的理论意义。它不仅是我国拨乱反正、改革开放的思想先导，而且为马克思主义理论的发展开辟了广阔的道路，其中包括马克思主义哲学中的实践理论本身。例如在80年代初期曾开展过一次关于检验实践的标准是什么的讨论。有的学者认为，实践是检验真理的标准，而主体的目的则是区别实践的成功与失败的标准，因此实践检验实际是主体的目的的检验。有的学者反对这种看法，认为实践检验认识不仅是实践的效果的检验，而且是实践的各种因素的综合检验。主体的目的取决于主体的价值标准，这实际涉及到价值标准在实践检验认识过程中的作用问题。后来学者们在讨论邓小平理论的过程中又提出了生产力标准、“三个有利于”标准与实践标准的关系问题，这也涉及到价值标准问题。这些问题的讨论进一步深化了实践标准理论，丰富和发展了马克思主义哲学。本文拟就价值标准在实践检验认识过程中的作用问题提出自己的看法，求教于哲学界和广大读者。首先谈一下什么是标准。标准是被人们用以衡量他物的东西，即用他物同它比较来确定他物的性质和数量的东西。长度的标准是尺，重量的标准是秤，有罪和无罪的标准是法律条文，善恶的标准是道德规范，美丑的标准是美感，等等，因此我们有度量衡，有法律标准，有道德标准，有艺术标准，还有政治标准、是非标准、利害标准、健康标准，等等。按照这种理解，我们要问真理的标准是什么？真理的标准只能是客观世界，也就是说，某一认识是不是真理，只能把它同客观世界相比较，看它同客观世界一致不一致，有多少一致，多少不一致。也就是说，各式各样的学科的真假只能以其对象为标准，物理学的标准是物理世界，生物学的标准是生命世界，心理学的标准是心理过程，社会学的标准是人类社会。教条主义的错误就在于把教条当成真理的标准，个人迷信的错误就在于把某个人的话当成真理的标准，而不管是否与客观世界一致。真理的标准不同于检验真理的标准。我们说实践是检验真理的标准，其含义说具体一点就是，实践是检验认识是不是真理的手段、方法、途径，而不是把认识同实践比较来确定其真假。上面提到的那种观点就是把认识同实践的效果相比较，把实践的效果当成了真理的标准，以实践的成功与失败来区分真理与谬误，这种观点同实用主义的有用就是真理的观点是很难区别的。我们必须把真理的标准同检验真理的标准（手段、方法、途径）区别开来，真理的标准是客观世界，检验真理的标准是实践。以实践来检验认识是不是真理，必须以真理标准为前提，换言之，实践检验真理就是检验认识是否与客观世界一致。实践检验认识不仅要运用真理标准，而且要有其他前提，价值标准是其中重要的一种。

关键词： 符号   试验   测定   方法   吸水率   材料试验   建筑   天然石料   天然石料   试样   准备  

标准号: EN 1925-1999

关键词： 评定   木基质产品   缺陷   木材   包装手段   类别   视觉的   分类(文献)   等级(质量)   工业   质量   分类   质量控制   特性   测定   极限(数学)   托盘   包装件  

标准号: EN 12246-1999

关键词： aldose reductase   sorbitol dehydrogenase   sorbitol pathway   substrate specificity   fluoro sugars   deoxy sugars  

摘要： The carbohydrate specificity of the two enzymes that catalyze the metabolic interconversions in the sorbitol pathway, aldose reductase and sorbitol dehydrogenase, has been examined through the use of fluoro- and deoxy-substrate analogs. Hydrogen bonding has been shown to be the primary mode of interaction by which these enzymes specifically recognize and bind their respective polyol substrates. Aldose reductase has broad substrate specificity, and all of the fluoro- and deoxysugars that were examined are substrates for this enzyme. Unexpectedly, both 3-fluoro- and 4-fluoro-D-glucose were found to be better substrates, with significantly lower K-m and higher k(cat)/K-m values than those of D-glucose. A more discriminating pattern of substrate specificity is observed for sorbitol dehydrogenase. Neither the 2-fluoro nor the 2-deoxy analogs of D-glucitol were found to be substrates or inhibitors, suggesting that the 2-hydroxyl group of sorbitol is a hydrogen bond donor. The 4-fluoro and 4-deoxy analogs are poorer substrates than sorbitol, also implying a binding role for this hydroxyl group. In contrast, both 6-fluoro- and 6-deoxy-D-glucitol are very good substrates for sorbitol dehydrogenase, indicating that the primary hydroxyl group at this position is not involved in substrate recognition by this enzyme. (C) 1998 Elsevier Science Ltd. All rights reserved.

关键词： “装船前检验”计划   商品检验工作   业务程序   商品价格证明   税则号  

摘要： 自六十年代以来，在世界经济贸易活动中，一些发展中国家为了保护本国有限的外汇资源，防止外汇流失，防止本国进口商漏逃关税，保护正常的关税收入，相继采用实施了“装船前检验”计划。目前，尽管各国在具体的政策中会有所侧重或有所不同，但共同点是十分明确的：即通过...