Ventral polarization vision in tabanids: horseflies and deerflies (Diptera: Tabanidae) are attracted to horizontally polarized light

Adult tabanid flies (horseflies and deerflies) are terrestrial and lay their eggs onto marsh plants near bodies of fresh water because the larvae develop in water or mud. To know how tabanids locate their host animals, terrestrial rendezvous sites and egg-laying places would be very useful for control measures against them, because the hematophagous females are primary/secondary vectors of some severe animal/human diseases/parasites. Thus, in choice experiments performed in the field we studied the behavior of tabanids governed by linearly polarized light. We present here evidence for positive polarotaxis, i.e., attraction to horizontally polarized light stimulating the ventral eye region, in both males and females of 27 tabanid species. The novelty of our findings is that positive polarotaxis has been described earlier only in connection with the water detection of some aquatic insects ovipositing directly into water. A further particularity of our discovery is that in the order Diptera and among blood-sucking insects the studied tabanids are the first known species possessing ventral polarization vision and definite polarization-sensitive behavior with known functions. The polarotaxis in tabanid flies makes it possible to develop new optically luring traps being more efficient than the existing ones based on the attraction of tabanids by the intensity and/or color of reflected light.     

Nestmate recognition in ants is possible without tactile interaction

Ants of the genus Camponotus are able to discriminate recognition cues of colony members (nestmates) from recognition cues of workers of a different colony (non-nestmates) from a distance of 1 cm. Free moving, individual Camponotus floridanus workers encountered differently treated dummies on a T-bar and their behavior was recorded. Aggressive behavior was scored as mandibular threat towards dummies. Dummies were treated with hexane extracts of postpharyngeal glands (PPGs) from nestmates or non-nestmates which contain long-chain hydrocarbons in ratios comparable to what is found on the cuticle. The cuticular hydrocarbon profile bears cues which are essential for nestmate recognition. Although workers were prevented from antennating the dummies, they showed significantly less aggressive behavior towards dummies treated with nestmate PPG extracts than towards dummies treated with non-nestmate PPG extracts. In an additional experiment, we show that cis-9-tricosene, an alkene naturally not found in C. floridanus' cuticular profile, is behaviorally active and can interfere with nestmate recognition when presented together with a nestmate PPG extract. Our study demonstrates for the first time that the complex multi-component recognition cues can be perceived and discriminated by ants at close range. We conclude that contact chemosensilla are not crucial for nestmate recognition since tactile interaction is not necessary.     

膜-生物反应器在我国的研究与应用新进展

膜-生物反应器(MBR)作为一种污水处理新技术,其研究和应用在我国受到了广泛关注.主要以1995-2006年发表在国内中文期刊上的关于MBR研究与应用的700多篇文献为基础,分析了与MBR构型、应用领域和研究机构等相关的文献数量分布,综述了在MBR新工艺、膜污染及其控制技术和污水处理类别等方面的研究进展,总结了MBR在污水再生利用中的应用概况,指出了未来MBR技术研究的挑战和工业应用的发展方向.     

烟气脱硫剂制浆系统一体化设计及应用

石灰石粉制浆系统是石灰石-石膏湿法烟气脱硫工艺中脱硫剂浆液干式制备系统的一个主要部分。针对石灰石粉制浆系统传统设计的不足,提出了石灰石浆液罐与粉仓一体化设计的优化方案,具有节省投资、占地小、设计简单紧凑、系统可靠和寿命长的优点,尤其适合我国老小燃煤机组烟气脱硫改造工程。目前已成功应用于多个烟气脱硫工程。     

国外生活垃圾厌氧发酵技术的工程应用

厌氧发酵技术能较好地实现城市生活垃圾的资源化、无害化和减量化,是目前垃圾处理技术一个新的重要发展方向,而国内尚无运行的厌氧发酵处理厂。针对国外厌氧发酵技术的应用情况和发展趋势,侧重于从工程应用方面总结已建厌氧发酵处理厂的发酵技术,为我国厌氧发酵处理厂的建设和运行提供一定的技术支持。     

综合防尘技术在开元公司的应用

主要介绍了采煤机高压引射降尘系统、液压支架自动喷雾、粉尘浓度在线检测超限自动喷雾等综合防尘技术在开元公司矿井中的应用。通过对降尘系统效果监测和分析,降尘效率达到84．1％,降尘效果明显,改善了作业场所的劳动卫生条件。     

室内甲醛检测方法及防治措施研究进展

介绍室内空气污染物甲醛的来源以及对人体健康造成的危害。探讨了现有室内甲醛污染物的检测方法,并对检测方法中存在的问题和应用条件的限制因素进行了讨论。为减少室内甲醛对人体健康造成的危害,提出了八种降解室内甲醛污染物的防治方法,并重点介绍了光催化氧化降解室内空气中甲醛的作用机理。提出了对检测方法和防治措施中存在问题的改进。改进检测方法和改良治理措施以及对装饰材料的选择是减少室内空气甲醛对人体健康造成危害的有效途径。     

有机废气治理技术的研究进展

有机废气治理问题是当前废气处理的难点问题之一。本文首先介绍了几类传统有机废气处理技术的发展现状,包括吸附法、吸收法、催化氧化法、生物处理法等。对这几类有机废气治理技术的应用机理、适用范围以及现存问题进行了综合地比较与分析。最后,对于近年来出现的几类新型有机废气处理技术,如膜分离法、光催化氧化法、综合处理法的发展前景进行了一定的展望并列举了几类新技术的工程应用实例。     

沼液利用途径分析

沼液是畜禽粪便厌氧发酵后的残留液,其中包含的矿物质丰富,如对其进行合理利用,将给人类带来一定的经济价值;如不妥善处置,沼液的随意排放将引起湖泊、河流富营养化等环境污染问题.我国沼液的主要利用方式包括直接归田、沼液浸种、叶面肥、饲料添加剂等,其中直接归田是当前沼液最主要的利用方式,但沼液直接归田也存在很大的环境风险.因此,开发低成本、高效益的沼液安全利用途径是我国今后研究的重要方向.     

氨法烟气脱硫工艺在燃煤锅炉的应用

介绍了氨法脱硫技术在国内外的应用情况以及氨法烟气脱硫工艺的工作原理和工程应用难点;分析了热电厂煤粉锅炉烟气脱硫的工艺路线特点及新型氨法脱硫工艺应用后取得了的显著效果;提出了氨法脱硫工艺存在的问题和发展前景。