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161.
Substituted urea compounds are well-known as potent inhibitors of juvenile hormone epoxide hydrolase (JHEH) of the tobacco hornworm Manduca sexta. Docking simulations of 47 derivatives inside JHEH were performed to gain insight into the structural characteristics of these complexes. The obtained orientations show a strong similitude with the observed in the known X-ray crystal structures of human soluble epoxide hydrolase (sEH) complexed with dialkylurea inhibitors. In addition, the predicted inhibitor concentration (IC50) of the above-mentioned compounds as JHEH inhibitors were obtained by a quantitative structure-activity relationship (QSAR) method by using comparative molecular field analysis (CoMFA) applied to aligned dataset. The best models included steric and electrostatic fields and had adequate predictive abilities. In addition, these models were used to predict the activity of an external test set of compounds that was not used for building the model. Furthermore, plots of the CoMFA fields allowed conclusions to be drawn for the choice of suitable inhibitors. 相似文献
162.
The investigation of object-by-attribute matrices is very common in statistics and data analysis with the aim of uncovering every possible relationship among objects and/or attributes. Formal Concept Analysis (FCA) is a method, which stems directly from partial order and lattice theory, which provides an efficient tool to symmetrically uncover linkages among objects and attributes whenever a relation stands among the two sets. It provides efficacious graphical representation and computes association rules between attributes, thus helping in the detection of possible synergism or antagonism of attributes. In this paper, FCA potentialities are discussed and described by means of a case study already investigated by other partial order techniques: the case of Lake Ontario sediment samples. Data derive from a ‘test battery’ for a simultaneous analysis of degradation of Lake Ontario samples, which are basically of two typologies: hygienic and toxicity tests. A multi-valued approach is adopted to cope with the ordinal feature of data. Results highlight interesting interaction among hygienic compounds and a synergism between the two toxicity tests. 相似文献
163.
分析了企业与外委单位的安全工作关系,明确了依法协调管理的依据和主要工作内容,对依法规避管理风险进行了探讨. 相似文献
164.
重庆市骨架公路网规划生态环境影响评价 总被引:5,自引:0,他引:5
战略环境评价作为一种促进可持续发展的重要工具,已经得到了广泛的关注。以重庆市骨架公路网规划生态环境影响评价为例,探讨一种基于规划路网与生态要素空间关系的评价方法。将评价要素分为两类,运用地理信息技术识别出规划路网对4种生态组分影响较大的地区和直接受规划路网影响的自然保护区,做出了空间分布图,并针对存在的问题给出了建议和对策,为合理设计和布设路网提供了依据。提出的基于空间位置关系的评价方法将会促进路网规划环境影响评价的开展。 相似文献
165.
Ruud Pleune 《Environmental management》1997,21(5):733-745
2 problem, which brought the issue into the energy debate, as well as the more general definition of the problem in the late
1980s as a greenhouse problem, were very important for determining the strategies of the organizations. It can be concluded
that strategies of Dutch environmental organizations with regard to climate change were strongly dependent on the context. 相似文献
166.
呼吸性煤尘与尘肺的剂量-反应关系分析 总被引:1,自引:0,他引:1
分析6个煤矿3082名煤尘接尘工人,其中包括51名尘肺患者接尘资料,首先通过比例换算法,按总煤尘EIC/TWA为1.5、总煤尘TWA/呼吸性煤尘TWA为3.82,将总煤尘EIC转换为呼吸性煤尘TWA;再用寿命表法分析累计接尘量与尘肺发病的剂量-反应关系,得到回归方程logit=5.714lgd-18.902(r=0.939),采用区间估计法,得接尘30年尘肺累计发病率为1%时,呼吸性煤尘TWA为6.52mg/m3,对估算结果取1.2的安全系数,呼吸性煤尘接触浓度管理限值为5mg/m3。 相似文献
167.
5 –106 times higher compared with less sensitive species. The use of assessment factors in effect assessment procedures may lead
to an underestimation of effects on the more sensitive species.
For many priority pollutants there is little information on their ecotoxicity. Predictive techniques are needed to compensate
for this lack of data. Knowledge of the relation between modes of action of compounds and interspecies variation in sensitivity
should be integrated in risk assessment procedures in order to make more efficient use of the limited financial resources
available. 相似文献
168.
公路交通事故危险性与事故原因的灰色关联分析 总被引:4,自引:1,他引:4
王岩 《中国安全生产科学技术》2006,2(4):56-60
交通安全既可以采用交通事故次数来评价,也可以根据交通事故的严重度进行衡量。不同的交通事故诱因,其事故后果的危险程度也不一致。运用灰色系统理论,以某段道路上交通事故多发点的“地点危险指数”为参考数列,以这些地点的不同事故诱因为比较数列,对“事故危险指数”和引发交通事故的各类事故原因之间作灰色关联分析,可以找出该路段上危害性最大的一些交通事故成因,在交通管理和交通安全宣传教育中有针对性地进行防治。本文以107国道1716—1883公里的交通事故数据为例给出了算例。 相似文献
169.
有机食品发展与生态保护政策相关性分析 总被引:2,自引:0,他引:2
通过对有机食品发展与“三农“问题、生物多样性保护、生态省建设、清洁生产、食品安全等国家生态保护政策之间的相关性进行了分析.在我国积极发展有机食品,是在农业领域内贯彻国家生态保护政策的具体体现. 相似文献
170.