Responses of ground-dwelling spiders to four hedgerow species on sloped agricultural fields in Southwest

Spiders are important predators in aeroecosystems and contribute to the control of agricultural nect nnnulatinns.Hahitat manage-ment such as the creation of new semi-natural habitats around or within fields enhances spider abundance and species diversity.Using pitfall traps,we investigated the effects of four hedgerow plant svecies.which serve as undisturhed and permanent semi-narimal habitats,on ground-dwelling spider activity density(a parameter of nonulation density and relative activitv)and species richness.Samples were ollected over two winter wheat and two summer maize growing seasons druing 2005-2007 in trial field 1(slope gradient of 20%)and field 2(slope gradient of 12%)at the Ziyane Experimental Site in Sichuan Province,China.The hedgerow species evaluated were Amorpha fruticosa(field 1).Vetiveria zizanioides(field 1),EulahODsis binata (field 2),and Afediraon sativa(field 2).CnmnareA to rnntrnl plots,hedgerow plots had significantly higher activity density and species richness of ground-dwelling spiders within strips in both fields 1 and 2 during the wheat growing season.The presence of hedgerow strins did not augment the activity density and species richness of ground-dwelling spiders within the crop fields during the wheat or maize growing seasons.The ground-dwelling spider activity density within hedgerow strips was significantly higher in the Vetiveria than in the AmorDha nlots and in the Medicago than in the Eulaliopsis plots,and the species richness was significantly higher in the Vetiveria than in the Amornha plots during the wheat season. Our results suggest that hedgerows may serve as important overwinterine sites for ground-dwelling spiders durinjthe wheat growing season.In addition,the diversification of agroecosystems by using hedgerow strips may be a viable strategy for maintaining ground-dwelling spider populations in agricultural areas.However,ground-dwelling spiders did not move into adiacent crop fields;therefore,future work should address the mechanisms of attracting spiders into crop fields,thereby contributing to the bio-control of pests.     

中小学生科学推理能力发展现状研究——以北京市中小学生为样本

以北京市部分中小学生为样本,采用LCTSR量表(2000版)中的部分题目进行测试,得出了科学推理能力随年级发展的规律,用Logistics回归曲线描述了不同年级学生在5个主要能力维度上的发展情况;指出教学因素对科学推理能力在不同维度上的发展具有显著影响,教学模式与能力属性的匹配程度影响其发展水平.     

聚苯胺纳米复合材料用于癌症诊疗的研究进展

共轭聚合物以其独特的结构和性能得到了广泛的关注.聚苯胺（PANI）纳米复合材料制备工艺简单、成本低廉、毒性低、易于功能化,从而在癌症治疗方面取得了巨大的进展.通过不同功能的化合物修饰制备的PANI纳米复合材料极大地拓宽了癌症治疗领域.基于PANI纳米复合材料,文章总结了其在癌症诊疗领域的光热治疗、协同治疗、多模态成像引导治疗和智能响应治疗的研究进展,并分析了其发展趋势.     

基于逻辑分区的仿箱鲀鱼群负载均衡分簇控制算法

为实现水下仿箱鲀鱼群体协同控制, 并降低网络节点间负载的不均衡性导致的能量损 耗, 提升群体续航能力, 提出一种基于逻辑分区的负载均衡分簇控制算法. 首先实现局部快速分簇, 减少节点间维护报文数量, 降低系统整体开销; 然后基于 簇内逻辑分区策略, 实现监测、 保障和侦察多区域协同控制, 并结合最小响应时间整编零散鱼群, 优化网络控制体系的同时提高组网灵活性; 最后在维护过程中采用区域节点角色转换机制, 实现网络负载均衡. 通过仿真分簇实验验证了算法的有效性, 并结合网络能量消耗、 网络生命周期和能量均衡性3个指标验证算法的可行性.     

Widespread adoption of Bt cotton and insecticide decrease promotes biocontrol services

Over the past 16 years, vast plantings of transgenic crops producing insecticidal proteins from the bacterium Bacillus thuringiensis (Bt) have helped to control several major insect pests and reduce the need for insecticide sprays. Because broad-spectrum insecticides kill arthropod natural enemies that provide biological control of pests, the decrease in use of insecticide sprays associated with Bt crops could enhance biocontrol services. However, this hypothesis has not been tested in terms of long-term landscape-level impacts. On the basis of data from 1990 to 2010 at 36 sites in six provinces of northern China, we show here a marked increase in abundance of three types of generalist arthropod predators (ladybirds, lacewings and spiders) and a decreased abundance of aphid pests associated with widespread adoption of Bt cotton and reduced insecticide sprays in this crop. We also found evidence that the predators might provide additional biocontrol services spilling over from Bt cotton fields onto neighbouring crops (maize, peanut and soybean). Our work extends results from general studies evaluating ecological effects of Bt crops by demonstrating that such crops can promote biocontrol services in agricultural landscapes.     

基金项目成果的评估系统初探

本文运用系统工程的思想和层次分析法（ＴｈＡｎａｌｙｔｉｃＨｉｅｒａｒｃｈｙＰｒｏ－ｃｅｓｓ）对已结题的基金项目进行跟踪管理，主要是对成果评估作了分析，讨论了建立成果跟踪管理评估系统层次结构的步骤，以及主要层次指标体系的判断矩阵，给出了基金项目成果跟踪管理评估系统。     

银白色花纹钢剑及其同步辐射X射线荧光分析

介绍了1枚传世银白色花纹钢剑的外部形态及其同步辐射X射线荧光分析的基本情况，并以此为基础对其材质、成花工艺、影响花纹钢性能的某些工艺因素进行了一些推测。该剑底色青黑，其上满布银白色重圈纹和组丝纹；它们都是平面花纹、自然花纹；看得见，难触摸；可摄影，不可拓摩；既自然流畅，又有一定规则。从科学分析可知，除铁外，基底和花纹都含有少量的铬、锰、铜。这种剑应是以两种含碳量相差较大且皆含有少量铬、锰、铜的铁碳合金加工成的；重圈纹和组丝纹的基本工艺当与髹漆中的犀皮相似，应是在多层积叠的钢铁料上，进行“做坑锻平”等一系列加工。该钢剑耐蚀能力较强，应与原料选择较好、锻打较为充分等都有一定关系。这种花纹钢的制作，从一个侧面反映了我国古代金属冶炼和加工的高超技艺，以及在古代世界花纹钢技术中的重要地位。     

Multiple Hierarchy Decision Analysis of Science Funds Management System

This article discusses a multiple hierarchy decision analysis in which the Analytic Hierarchy Pro     

非线性液固耦合系统的一个广义变分原理

基于势流理论，在液体小幅度流动的前提下，考虑水中结构大变形的影响，对于具有自由液面的非线性液固耦合系统，提出了一个广义变分原理，它为这类问题的有限元数值分析提供了有力的理论依据．