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81.
Peter Witzgall Jean-Pierre Chambon Marie Bengtsson C. Rikard Unelius Monica Appelgren Gyorgy Makranczy N. Muraleedharan Darwin W. Reed Klaus Hellrigl Hans-Ruedi Buser Eric Hallberg Gunnar Bergström Miklos Tóth Christer Löfstedt Jan Löfqvist 《Chemoecology》1996,7(1):13-23
Summary The geometric isomers (E,E)-, (E,Z)-, (Z,E)-, and (Z,Z)-8,10-dodecadien-1-yl acetate were identified as sex pheromone components or sex attractants in the tribes Eucosmini and Grapholitini of the tortricid subfamily Olethreutinae. Species belonging to the more ancestral Tortricinae were not attracted. Each one isomer was behaviourally active in males ofCydia andGrapholita (Grapholitini), either as main pheromone compound, attraction synergist or attraction inhibitor. Their reciprocal attractive/antagonistic activity in a number of species enables specific communication with these four compounds.Pammene, as well as otherGrapholita andCydia responded to the monoenic 8- or 10-dodecen-1-yl acetates. Of the tribes Olethreutini and Eucosmini,Hedya, Epiblema, Eucosma, andNotocelia trimaculana were also attracted to 8,10-dodecadien-1-yl acetates, but several otherNotocelia to 10,12-tetradecadien-1-yl acetates. The female sex pheromones ofC. fagiglandana, C. pyrivora, C. splendana, Epiblema foenella andNotocelia roborana were identified. (E,E)- and (E,Z)-8,10-dodecadien-1-yl acetate are producedvia a commonE9 desaturation pathway inC. splendana. CallingC. nigricana andC. fagiglandana females are attracted to wingfanning males. 相似文献
82.
一种分离培养硫酸盐还原菌的改进方法 总被引:12,自引:0,他引:12
On the base of the characteristics of sulfate-reducing bacteria (SRB) growth and dish cultivated method, a new method for isolation and cultivation of SRB is established. It is dilution spread and repeat dish sandwish cultivated method with the exellence of dilution spread and embeded growth, and it can help separation and identification of SRB. The method has simple operation and less equipment. And using this method, the natural SRB drop was successfully gained, and small agar pieces containing SRB drop were acquired in easiness. The brief SRB transfering operation in strict anaerobic condition was in-deed realized. Fig 1, Ref 7. 相似文献
83.
84.
高效铜绿微囊藻溶藻菌WJ6的分离鉴定及溶藻特性 总被引:1,自引:0,他引:1
以铜绿微囊藻为研究对象,从富营养化水体分离了一株高效溶藻菌,通过分析形态学、生理生化特征及16S rDNA序列比对,鉴定了该溶藻菌株,分析了该菌株对铜绿微囊藻的溶藻方式、溶藻特性及其不同培养时期、不同浓度菌液及不同环境因子对溶藻效果的影响,并探讨了其可能的溶藻机制.研究表明:WJ6属于沙雷氏菌属(Serratia sp.GenBank登录号为KY462187);溶藻菌WJ6以胞外释放溶藻物质为主直接溶藻为辅的溶藻方式;溶藻菌WJ6处于对数期时的溶藻率最高达87.50%;菌液浓度达1.4×109CFU/mL以上,溶藻率最高为95.69%;在30℃、pH8条件下,溶藻率达90.00%;改良的基本培养基培养的溶藻菌溶藻率最高达98.50%;铵离子浓度大于2mol/L时,溶藻菌的溶藻率98.33%;当盐度为0.5%时,溶藻率较高为92.77%.溶藻菌株WJ6是1株高效溶铜绿微囊藻菌,在富营养化治理方面具有较好的应用前景. 相似文献
85.
86.
Experimental studies were done with a small pipe with a diameter of 0.043 m and a large pipe with a diameter of 0.49 m to demonstrate the flame propagation suppression with inertia isolation in a long duct. Tests were carried in an ignition section containing propylene/air mixture near stoichiometric concentration and generating a peak flame propagation speed of approximately 100 m/s. The ignition section is connected to a section filled with an inert gas, another section with flammable mixtures, and finally a sufficiently long, ambient section to accommodate flame propagation. The critical length of the inert gas section required for successful suppression of flame from the igniting the flammable section is found to be 0.6 m for CO2 and 0.9 m for N2 in the large pipe and 0.2 m for CO2 and 0.3 m for N2 in the small pipe. Additional tests with a 3 m of ignition section and peak flame propagation speed of 225 m/s showed that the critical length for successful suppression by CO2 is only increased slightly to 0.9 m, confirming that the suppression is a result of inertia isolation rather than inert gas dilution. Finally, application of the results in responding to large-scale leak into a long, underground duct is discussed. 相似文献
87.
Swimming pools are considered to be the prime source for public exposure to trihalomethanes (THMs), mainly chloroform, because of their use for hygienic purposes. High doses of chlorine are easily perceptible by smell. The aim of this study was to measure simultaneously the THM levels in urine and blood of swimmers and in pool water itself (from city and university swimming pool), in order to investigate further the relationship between substances in different matrices at known environmental levels with uptake of these substances in indoor swimming pools. Volatile analytes were isolated and preconcentrated from the samples by thin layer headspace analysis (TLHS) with autogenous generation of the liquid sorbent. Chloroform, bromodichloromethane and dibromochloromethane were detected in the urine of all persons attending a swimming pool. Concentrations of THM compounds varied in the case of each swimmer. The research confirmed that approximately 10% of the volatile haloorganic compounds are excreted in urine in the unchanged form. 相似文献
88.
Ability of Wildlife Overpasses to Provide Connectivity and Prevent Genetic Isolation 总被引:2,自引:0,他引:2
Abstract: We reviewed research on wildlife overpasses in the context of their genetic effectiveness to provide connectivity between population patches that have been isolated by road construction. The potential ecological consequences of such habitat fragmentation include reduction of gene flow between subpopulations and hence an increase in genetic differentiation and a decrease in genetic diversity. Among the solutions to provide connectivity between patches isolated by roads, wildlife overpasses are one of the most expensive alternatives. Despite the high costs associated with their construction, most of the studies assessing their use by wildlife remain observational, reporting evidence for passage use but few data on the number of individual crossings. Moreover, the use itself of wildlife overpasses does not appear sufficient to assess their effectiveness from a genetic viewpoint because a minimum number of individuals is required to assure gene flow between population patches and because the spatiotemporal dimension of individual movements and demographic parameters of subpopulations must be considered. So far, there is no evidence that wildlife overpasses do or do not efficiently address genetic issues. This lack of data is probably due to the fact that few mitigation efforts have implemented monitoring programs that incorporate sufficient experimental designs into pre- and postconstruction evaluation. To assess the genetic effectiveness of wildlife overpasses, long-term monitoring programs, including fieldwork and genetic analyses, are needed. 相似文献
89.
一株耐镉细菌的分离及其富集Cd的机理 总被引:4,自引:0,他引:4
从重金属镉污染土壤中筛选到一株对镉具有较强抗性和富集能力的细菌RC。经形态学观察和生理生化鉴定以及16SrDNA序列分析,RC为蜡状芽孢杆菌(Bacillus cereus)。在不同镉浓度液体培养条件下研究了菌体的生长曲线,并探讨了RC菌株对Zn、Cu的抗性,结果显示RC对不同重金属的抗性机制存在一定的差异。利用扫描电镜、透射电镜观察了镉在RC胞内外的沉积作用及分布情况,结果表明,在镉浓度为150 mg/L时菌体细胞壁及其内部可见大量的高电子密度颗粒,同时在菌体表面也有沉淀物附着。因此,胞内外沉积作用可能是该菌对高浓度镉的抗性和富集作用的重要途径。通过红外光谱探讨了RC积累镉前后细胞壁表面化学基团的变化情况,结果发现RC的细胞壁上参与积累作用的化学官能团主要有—OH、—NH、—CO和—CO—NH—等。 相似文献
90.
Summary.
Darna bradleyi Holloway, D. trima Moore, Setothosea asigna van Eecke and Setora nitens Walker are sympatric and coseasonal limacodid moths in plantations of oil palm, Elaeis guineensis Jacq. (Arecales: Palmae), in Borneo, southeast Asia. We tested the hypothesis that these four species maintain reproductive
isolation through specificity in diel periods of communication, microlocation for communication and/or communication signal
(pheromone). Studying diel periodicity of calling behavior by female moths and response by male moths to traps baited with
virgin females or synthetic pheromone, we determined that sexual communication of D. bradleyi and D. trima took place from ˜17:30 to 18:45 hr and that of S. asigna and S. nitens from ˜18:45 to 20:00 hr and from ˜18:30 to 19:30 hr, respectively. Over 80% of male S. asigna and S. nitens were captured in pheromone-baited traps suspended >5 m high, whereas male D. bradleyi and D. trima were captured mostly in traps <5 m high. Synthetic pheromone baits attracted male moths in a species-specific manner. Moreover,
baits containing both S. asigna and S. nitens pheromones failed to attract any male moths, indicating that female S. asigna and S. nitens, with overlapping communication periods, use bifunctional pheromone components that attract conspecific males while repelling
heterospecifics. Similarly, addition of D. bradleyi pheromone to S. asigna or S. nitens pheromone reduced attraction of male S. asigna and S. nitens. The failure of D. bradleyi and D. trima, which overlap in time and microlocation for communication, to evolve bifunctional pheromones may be attributed to the recent
occurrence of sympatry between D. bradleyi and D. trima in Borneo, apparently too recent for bifunctional pheromones to have evolved. We conclude that D. bradleyi, D. trima, S. asigna and S. nitens utilize any or all of diel periodicity, intra and interspecific effects of communication signal and/or microlocation for
signaling, allowing these limacodids to co-inhabit the same habitat and remain reproductively isolated.
Received 5 May 2000; accepted 18 August 2000 相似文献