A sensitive, rapid ferricyanide-mediated toxicity bioassay developed using Escherichia coli

A need for rapid toxicity techniques has seen recent research into developing new microbiological assays and characterising their toxicity responses using a range of substances. A microbiological bioassay that determines changes in ferricyanide-mediated respiration for toxicity measurement (FM-TOX) shows particular promise. The development and optimisation of an improved FM-TOX method, incorporating novel features, is described using Escherichia coli as the biocatalyst. Omission of an exogenous carbon source, used in previously described FM-TOX assays, substantially improves the assay sensitivity. In addition, the development of a two-step procedure (toxicant exposure followed by determination of microbial respiratory activity) was found to enhance the inhibition of E. coli by 3,5-dichlorophenol and four other toxicants, compared to single-step procedures. Other assay parameters, such as the ferricyanide concentration, exposure times and optical density of the biocatalyst were also optimised, sometimes based on practical aspects. Toxicity tests were carried out using the adopted technique on both organic and inorganic toxicants, with classic sigmoid-shaped dose-response curves observed, as well as some non-standard responses. IC₅₀ data is presented for a number of common toxicants. The optimised assay provides a good foundation for further toxicity testing using E. coli, as well as the potential for expanding the technique to utilise other bacteria with complementary toxicity responses, thereby allowing use of the assay in a range of applications.     

论有名合同与无名合同的法律适用

合同法分则中具体规定了15种有名合同的法律适用,并对15种有名合同之外的无名合同规定了法律适用的原则。结合合同法总则的规定,可以对合同的法律适用作出如下归纳：15种有名合同适用总则和相应的分则;15种之外的有名合同适用总则和相应的其他法律规定;无名合同则适用总则和比照适用最相类似的分则。而在比照适用法律时,还是要遵循诚实信用原则、交易习惯优先以及适度的法官自由裁量权。     

承包商怎样搞好工程计量浅述

根据长期从事工程计显与支付工作所获得的经验，全面、系统地阐述了承包商在工程实施中如何通过搞好工程计量工作，达到获得较好经济效益的目的。     

国际承包工程代理商的作用

对国际承包工程代理商的作用与委托代理商的必要性，以及选择代理商的标准进行了论述。     

1953年农业合作化运动中反冒进的历史考察及启示

从历史的角度考察了1953年农业合作化中的“左”倾冒进错误的表现、后果、形成原因及中国共产党为纠正“左”倾错误所做出的不懈努力．得出四条重要启示：必须从我国农村生产力水平较低的现实出发，使农村的生产关系与之相适应；必须充分发扬民主，善于倾听群众的声音，切实维护广大农民的根本利益；必须一直以解放和发展生产力为根本目的，始终坚持发展生产是“农村中压倒一切的中心工作”的方针；必须注重正确的方法，深入进行调查研究，采取典型示范，不搞群众运动．     

品牌塑造:企业与顾客心理契约构建

21世纪将是一个品牌竞争的时代。品牌是由企业创造和呵护，由消费者主导，通过产品和消费来表达的一种复杂而独特的商业关系与符号。品牌是企业与顾客之间的一种心理契约，品牌塑造的过程就是企业与顾客心理契约构建过程。诚信价值观是品牌的基本文化内涵，也是企业与顾客构建心理契约的支点。     

Multicriteria modelling for a repair contract problem based on utility and the ELECTRE I method

Each alternative for a repair contract implies a specific responsetime and related cost. The response time is associated withthe commitment of repair time, based on the contract. A decisionmaker chooses the best alternative taking into account the systemperformance and the cost of the contract. This problem has beenanalysed through a multicriteria decision model. This decisionmodel supports decision makers in the determination of the bestcombination of contracting conditions. The decision model proposedallows the decision maker to quantify the consequences of anaction taking into account two basic criteria: the cost of thecontract and the system performance. Two different decisionmodels have been built to support decision makers. These decisionmodels are based on different multicriteria approaches. Thefirst, reported in a previous paper, is based on the multiattributeutility theory (MAUT). The model presented in this paper isbased on the ELECTRE I method combined with utility functions.The paper presents the main theoretical aspects related to bothapproaches and practical implications related to model building.A numerical application is presented in order to illustratethe use of the decision model.     

论无预售许可证商品房预售合同之效力

无预售许可证商品房预售合同违反了法律的强制性规定，但这并不导致此类合同必然无效。对无预售许可证商品房预售合同的效力应该区分不同情况进行分析，具体有无效和可变更可撤销两种情形。     

论旅游合同性质及我国旅游法律制度的完善

旅游业是21世纪的朝阳产业,在旅游业大发展的社会环境下,如何完善我国的旅游法律制度,加强旅游法律法规的立法监督与管理,有效改善旅游市场秩序和促进旅游业健康发展已成为一个突出的急迫性课题.     

十论改革完善我国科技人力资源开发与管理制度--论聘约标准的构建及其科学使用

针对我国聘约标准长期缺失的客观事实,探讨了聘约标准的基本内容和构建原则、方法及应注意的问题,并简要讨论了如何合理、科学地使用聘约标准。