科创中国

Insect source-sink dynamics are vital to ecologically intensive pest management. Maintaining sink plant hosts,or "trap crops",and destroying alternate hosts or breeding places adjacent to the field crop are effective pest management strategies for some arthropods. However,determining whether a host acts as a source or a sink is challenging, especially when the pest species is highly mobile and polyphagous. The western tarnished plant bug,Lygus hesperus,is highly polyphagous,and can utilize >300 hosts. Its presence has been documented in 26 roadside weed hosts in the Texas High Plains.Previous studies demonstrated that L. hesperus prefer alfalfa over cotton and several alternate weed hosts.A four-year project involved surveying and sampling for L. hesperus in the agricultural landscapes of several sub-regions of the southwestern United States,including the Texas High Plains. In Texas,geographic information of the landscape vegetation complex was compiled from a 150 km radius in the Texas High Plains. In one study,fifty irrigated cotton fields representing the crop diversity within this region were sampled via sweep-net for 10 weeks. This effort also included sampling of up to six noncotton insect habitats within a 3 km radius of each field. Seasonal average L. hesperus abundance data were regressed with 27 field characteristics( variables),including habitat-specific land cover,distance between focal cotton fields and non-cotton habitats,longitude,latitude,elevation,habitat heterogeneity index,and several environmental / ecological variables. Significant variables were selected using a stepwise regression at 15% probability rate. A 10-parameter linear model explained 93% of the variation in the data. Major parameters contributing significantly to variation in L. hesperus abundance in cotton were corn and sunflower acreages,focal cotton field distances from several non-cotton hosts,and habitat heterogeneity index. In addition,field marking-and-capture studies were conducted using protein markers and enzyme-linked immunosorbent assays to characterize L. hesperus intercrop movement behavior. The field marking-and-capture approach can be used to study the effects of various crop management practices on L. hesperus intercrop movement and can potentially be applied to other pests and cropping systems.

随着肿瘤分子生物学研究的不断深入,检测肿瘤组织中mRNA和蛋白的表达有助于揭示肿瘤的发生、分子机制和寻找相关分子标志物.转录水平上可利用RT-PCR或cDNA芯片技术检测基因表达、转录组改变以及克隆肿瘤相关基因.蛋白水平上可利用Western blot法、2D电泳和飞行质谱技术检测肿瘤组织中蛋白表达和蛋白质学改变.这对提高检测敏感度和增加结果可信性,获得高质量RNA或蛋白样品十分关键.本组实验比较手动冻结破碎器具SK-100和普

印刷包装生产线是一个工序复杂的动态离散事件系统(DES),采用建模、仿真和优化相结合的研究方法,合理地安排生产系统的资源并提高生产线的生产率.在印刷包装生产系统框架的基础上,采用Petri网建立了系统的赋时PN模型,并将该模型直观地映射为e M-Plant仿真模型.通过该模型的仿真,分析了生产设备的性能和指标参数,运用约束理论(TOC)找到影响该系统生产率的生产瓶颈,提出了生产线的改进方案并验证其可行性,优化了生产过程.

分析了我国农产品流通中存在的问题,介绍了国外发达国家成功的农产品流通模式,最后,提出发展我国农产品流通的相关对策建议.

介绍了变频调速技术的节能原理,阐述了基于PLC和变频器控制的恒压供水特点,完成了一台变频器控制四台水泵实现恒压供水的具体要求,设计了硬件控制回路和软件编程方法.实际运行证明,变频恒压供水系统控制简单、可靠性高、保护功能完善、节能效果明显.

介绍了葠窝水库发电厂旧监控系统,深入地分析了原有监控系统的现状,从设备、功能等方面剖析了其更新改造的必要性,并且从运行、维护、安全可靠及电站与调度通信等方面考虑,该厂必须进行监控系统的更新改造;在此基础上,按照"无人值班,少人值守"的设计总原则,对该电厂的保护监测系统、视频监控系统、大屏幕系统及励磁装置等设备,分别提出了具体改造方案和主要配置设备,并成功地实现了更新改造.

针对桃林口小坝及引青西线工程因受当时设计、施工条件限制存在诸多问题的现状,为保证引青济秦工程的安全运行,保障秦皇岛市用水安全,实施桃林口小坝加固及引青西线改造工程.分析了原有工程存在的具体问题,提出改造工程设计方案,通过经济评价,工程在经济上合理,并具有显著的社会效益.