生态环境内涵的回顾与思考

本文回顾了近20年来生态环境一词在社会上和国内外的使用情况，讨论了其科学内涵。认为生态环境是由生态关系组成的环境，是生命有机体赖以生存、发展、繁衍、进化的各种生态因子和生态关系的总和。文章还论述了生态建设的涵义及其在实施科学发展观、推进可持续发展中的重要作用。     

旅行社关系营销的新方法

旅行社行业经过一个时期的繁荣后,已经进入了一个利润微薄的时代,在过度竞争的环境下,旅行社要靠关系营销来保持稳定的客户源,创建品牌,降低客户对价格的敏感度。     

体育专业在校生运动损伤情况调查分析

采用问卷调查和实地访问相结合的方法,对河南省部分高校体育院、系的体育教育专业在校学生受伤情况进行了调查,从发生运动损伤的性质、运动项目、受伤的部位、引起损伤的原因等方面分析,结果表明：在大学期间学生受伤情况相当普遍,已严重影响正常教学和训练.建议应尽快强化学生预防损伤的意识并提出预防运动损伤的综合性措施.     

论审美关系的本质

在人与自然构成的多种关系中,审美关系是人与自然之间诸多关系的一种,具体表现为无功利性,形象性,和以情感为中心特征。人的社会实践活动促进了人脑的进化和生理感官的成熟,为审美关系的存在提供了基础。随着社会的不断发展,审美关系也在逐步向前推进。同人与自然的其他关系相比,审美关系具有兼容性、个体独特性和历史性等特征。     

一类捕食者——食饵模型的定性分析

本文对一类捕食者——食饵模型进行定性分析,得到了非平凡平衡点全局稳定性的条件和正平衡点周围存在唯一极限环的充分条件,并且本文给出了1个关于这类系统“大范围”极限环的存在唯一性定理。     

Pharmacodynamic profile of CQP 201-403, a novel 8α-amino-ergoline

Summary The profile of action in animals of CQP 201-403, a novel 8-amino-ergoline, is in most aspects that of a very potent dopaminomimetic, both as a prolactin secretion inhibitor, and at the levels of the CNS and the cardiovascular system. Qualitatively CQP 201-403 differs slightly from bromocriptine and apomorphine in its effects on the CNS (no influence on serotonin metabolism in the rat cortex; induction of masculine mounting behavior in rats) and the cardiovascular system of the dog (reflex tachycardia in response to a blood-pressure fall). In man the new compound proved to be highly active in lowering prolactin serum levels and to be more potent than bromocriptine (Parlodel^®).In memory of Dr Annemarie Closse, who died 14 June 1987.     

Quantitative genetic models of sexual selection

Summary Quantitative genetic models of sexual selection have disporven some of the central tenets of both the handicap mechanism and the sexy son hypothesis. These results suggest that the good genes approach to sexual selection may generally lead to erroneous results.Runaway sexual selection seems possible under a wide variety of circumstances. Quantittive genetic models have revealed runaway processes for sexually selected attributes expressed in both sexes and for attributes of parental care. Furthermore, the runaway could occur simultaneously in a series of populations that straddle an environmental gradient. While the models support the feasibility of runaway processes, empirical studies are needed to evaluate whether runaways actually happen. Estimates of critical genetic parameters are particularly needed, as well as measures of natural and sexual selection acting on the same population.The models also show that sexual selection has tremendous potential to produce population differentiation, particularly in epigamic traits. Differentiation is promoted by indeterminancy of evolutionary outcome, transient differences among populations during the final slow approach to equilibrium, sampling drift among equilibrium populations, and the tendency of sexual selection to amplify geographic variation arising from spatial differences in natural selection. Recent work with two- and three-locus models of sexual selection has produced results that parallel the results of the polygenic models^36–38,58. Thus the feature of indeterminate equilibria (outcome dependent on initial conditions) is common to both types of model.