Identification of a new predaceous stink bug pheromone and its attractiveness to the eastern yellowjacket

Summary Males ofPodisus fretus (Hemiptera: Pentatomidae) release a long-range attractant pheromone containing linalool (49.0%), (E)-2-hexenal (34.5%), benzyl alcohol (12.0%), nerolidol (2.0%),-terpineol (1.1%), and traces of several other compounds. The eastern yellowjacket,Vespula maculifrons (Hymenoptera: Vespidae), is attracted to artificial pheromones forP. fretus and for the sympatric species,Podisus maculiventris.The authors thank Mr T.J. Henry of the USDA Systematic Entomology Laboratory and Dr J.E. McPherson, Southern Illinois University, for examining the pentatomid species and Dr A.S. Menke, USDA-SEL, for determining the yellowjacket species. We also thank S. Wilzer for technical assistance. Mention of a company name does not imply endorsement by the US Department of Agriculture.     

Chemical attraction of the eastern yellowjacket,Vespula maculifrons (Hymenoptera: Vespidae)

Summary Workers and queens of the eastern yellowjacket,Vespula maculifrons, are attracted to the artificial long-range attractant pheromone of the predaceous pentatomid,Podisus maculiventris. A 11 mixture of linalool or -terpineol and (E)-2-hexenal is as attractive toV. maculifrons workers as the pheromone.We thank A.S. Menke of the Systematic Entomology Laboratory, USDA, for identifying the yellowjackets. Mention of a company name does not imply endorsement by the US Department of Agriculture.     

Sex pheromone of the pine sawflyDiprion pini (Hymenoptera: Diprionidae): Chemical identification,synthesis and biological activity

The main component of the sex pheromone secretion of femaleDiprion pini L. (Hymenoptera: Diprionidae) from insects collected both in Finland and in France has been identified as athreo-3,7-dimethyl-2-tridecanol (8 ng per female) stereoisomer by GC-MS and synthesis. The secretion also contains lower and higher homologues in small amounts (1–4% of the main component). Combined gas chromatographic-electroantennographic detection showed activity in both natural and esterified extracts (acetates and propionates); the esters of the main component gave the largest responses. The acetates and propionates of the eight stereoisomers of 3,7-dimethyl-2-tridecanol were synthesized from enantiomerically highly enriched (>99% ee) building blocks. The stereochemistry of the main component was established to be (2S,3R,7R)-3,7-dimethyl-2-tridecanol by GC analysis of the natural material. It was purified by liquid chromatography prior to the GC analysis of both its pentafluorobenzoates and its isopropylcarbamates on a non-chiral polar column (ECD) and a chiral column (NPD), respectively. Field tests demonstrated that both the acetate and propionate of the main component (100 g of each applied on cotton roll dispensers) were active in attracting males, with or without the presence of several of the minor compounds. Experiments with smaller amounts of the acetate and the propionate (1 g in France and 50 g in Finland) demonstrated that the propionate was more active than the acetate, and that it also caught more males than a blend of the two compounds.     

利用数据仓库技术实现网络流量数据分析

阐述了利用数据仓库的聚合技术，通过设计不同粒度的分级表，实现了对网络流量的海量数据的高效处理．给出了流量分析数据库的设计思想及结构描述，讨论了数据聚合过程．通过采用梯形式的聚合方式，在保证有用信息粒度的基础上，可以大大减少数据量和存储空间，提高查询效率．     

重新蓄水后的白洋淀鲫鱼的生物学分析

本文论述了重新蓄水后白洋淀鲫鱼的食性、年龄生长和繁殖。鲫鱼主要以硅藻、枝角类和水生维管束植物为食。可分为五个年龄组，平均肥满度为３．１３２４，Ⅱ－Ⅲ龄组生长最快、最好。绝对怀卵量为５１２７～６１５９６粒，相对怀卵量为７２．５４～４０２．５９粒／克，性腺成熟系数为４．２９３％～１３．０７２％。     

黑斑蛙Dmrt4基因的克隆测序

Dmrt基因家族是新近发现的一个与性别决定相关的基因家族.该家族成员都含有一个新的具有DNA结合能力的保守基序--DM结构域,它们在性别决定和分化发育的调控中担负重要的功能.本文采用简并PCR技术,扩增并克隆了黑斑蛙基因组中的DM结构域,经序列分析,获得了Dmrt家族的一个成员rnDmrt4.通过对不同进化地位的物种进行Dmrt4基因的氨基酸序列聚类,发现了Dmrt4基因在系统进化中具有高度保守性,提示该基因在性别分化和功能维持上可能具有重要作用.     

基于DM643的交通信息采集系统

为实时、准确获取道路交通信息,满足当前智能交通系统的应用需求,设计并实现了一种基于高性价比DSP硬件平台的嵌入式交通信息采集系统。给出了视频输入输出接口／电路和网络通讯接口电路的设计,并基于DSP／BIOS开发了系统驱动程序。实验结果表明,该系统具有很好的稳定性和实时性。     

嵌入式视频处理EDMA数据存储

嵌入式系统中内部RAM存储空间普遍较小,无法直接将视频处理系统处理的大量数据存储到内部RAM上,而增强型直接内存存取（EDMA）可独立于CPU进行后台批量数据传输,并行用于嵌入式视频处理系统快速数据交换。以嵌入式平台TMS320DM6446 DSP为例,详细介绍了如何使用EDMA优化数据存取的策略。     

井下电机车通信系统研究与电路设计

5提出了在架线电机车载波通信系统中,用数字通信取代模拟通信方式。设计出二次调制系统;采用连续可变斜率增量调制（CVSD）实现模拟语音信号与数字编码的转换,采用二进制相对相移键控（2DPSK）作为数字调制方式。文中给出了该通信系统中主要技术参数的确定原则和部分具体设计电路。通过整体系统电路的试验调试,达到了设计要求。     

基于TMS320DM642的视频监控系统

本文提出一种基于TI公司TMS320DM642EVM平台的视频监控系统解决方案,通过实现MPEG4视频编码模块及编码后视频码流的实时网络传输模块,从而实现该方案的视频远程监控功能.