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In 1996, the exotic white-spotted tussock moth (WSTM), Orgyia thyellina (Lepidoptera: Lymantriidae), was discovered in Auckland, New Zealand. Because establishment of WSTM would threaten New Zealand's orchard industry and international trade, eradication of WSTM with microbial insecticide was initiated. To monitor and complement eradication of WSTM by capture of male moths in pheromone-baited traps, pheromone components of female WSTM needed to be identified. Coupled gas chromatographic–electroantennographic detection analysis of pheromone gland extract revealed several compounds that elicited responses from male moth antennae. Mass spectra of the two most EAD-active compounds suggested, and comparative GC-MS of authentic standards confirmed, that they were (Z)-6-heneicosen-11-one (Z6–11-one) and (Z)-6-heneicosen-9-one, the latter termed here thyellinone. In field experiments in Japan, Z6–11-one plus thyellinone at a 100:5 ratio attracted WSTM males, whereas either ketone alone failed to attract a single male moth. Addition of further candidate pheromone components did not enhance attractiveness of the binary blend. Through the 1997–1998 summer, 45,000 commercial trap lures baited with 2000 g of Z6–11-one and 100 g of thyellinone were deployed in Auckland towards eradication of the residual WSTM population.Dedicated to my dear mother in honor of her 75th birthday  相似文献   
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This study was undertaken to identify sex pheromone components of nettle caterpillars Darna trima and Darna bradleyi (Lepidoptera: Limacodidae) whose larvae defoliate oil palm, Elaeis guineensis, in southeast Asia. Coupled gas chromatographic–electroantennographic detection (GCEAD) analyses of pheromone gland extracts revealed two antennally active compounds produced by female D. trima and two by female D. bradleyi. Molecular structures of these candidate pheromone components were identified by electron-impact and chemical-ionization mass spectrometry; retention-index calculations on DB-5, DB-23, and DB-210 columns; microanalytical treatments, as well as syntheses of "auxilliary" compounds that facilitated identification of the compounds. The compounds from D. trima were 2-methylbutyl (E)-7,9-decadienoate (A) and (E)-2-hexenyl (E)-7,9decadienoate (B); from D. bradleyi we identified methyl (E)-7,9-decadienoate (C), and isobutyl (E)-7,9-decadienoate (D). In field experiments in Malaysia, (S)-2-methylbutyl (E)-7,9-decadienoate (SA) in combination with B proved to be essential and synergistic pheromone components for attraction of male D. trima. (R)-2-Methylbutyl (E)-7,9-decadienoate (RA) had no behavioral activity. Compound D singly attracted male D. bradleyi, but addition of C to D at a 1 : 10 ratio significantly enhanced attractiveness of the bait. Synthetic pheromone blends were more effective trap baits than unmated female moths and could be developed for monitoring populations of D. trima and D. bradleyi in Asian oil palm plantations.  相似文献   
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Minimum substrate loss is required for resist strip of high dose, ultra shallow junction implant for source/drain extensions. Silicon surface oxidation of downstream plasma resist strip results in silicon recess of the source/drain extension regions. This paper reports the study of silicon surface oxidation for different resist strip plasma chemistries and the effect of plasma strip process parameters such as power, pressure and temperature on silicon surface oxidation. A good agreement was found between optical ellipsometry, XPS (X-ray photoelectron spectroscopy) and TEM (transmission electron spectroscopy) for thickness measurement of very thin (<20 Å) oxide grown on silicon surface due to plasma exposure. Selectivity of crust breakthrough and resist removal over silicon oxidation was also discussed in this paper along with dopant loss.  相似文献   
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Four hundred and eight consecutive patients scheduled for cataract surgery under local anaesthesia were randomly allocated to one of two types of regional anaesthesia. One group was given the standard retrobulbar block combined with a facial nerve block of the O'Brien type, and the second group was given a modified peribulbar block. Results indicate that it is possible to achieve a high degree of reliability, within a relatively short time, from the modified peribulbar block without the major complications associated with retrobulbar block.  相似文献   
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(3S, 13R)-3, 13-Dimethylheptadecane [(3S, 13R)-3, 13-dime-17Hy] is the major pheromone component of the western false hemlock looper (WFHL),Nepytia freemani. In comparative gas chromotographic-electroantennographic detection (GC-EAD) analyses of stereoselectively synthesized isomers, 1 pg of (3S, 13R)-dime-17Hy elicited significantly stronger electrophysiological responses by male WFHL antennae than did 1 pg of separately injected (3R, 13R)-, (3R, 13S)- or (3S, 13S)-3, 13-dime-17Hy. In field experiments with individually tested stereoisomers. (3S, 13R)-3, 13-dime-17Hy was the only stereoisomer to attract males, but the four-stereoisomer blend was 3.6 times more attractive. Quaternary and all binary combinations of (3S, 13R)-3, 13-dime-17Hy with the other stereoisomers were equally attractive, suggesting that synergisytic behavioral activity in WFHL resided with either one of (3R, 13R)-, (3R, 13S)-, or (3S, 13S)-3, 13-dime-17Hy. Because optical isomers of (di)methylhydrocarbons do not separate on currently available columns, it remains unknown whether female WFHL also produce a four-stereoisomer pheromone blend. Substitutionality of pheromone stereoisomers without loss of behavioural activity has not previously been reported, but favorably compares with the concept of pheromone redundancy that was first suggested for the multiple pheromone component blend of the cabbage looper moth,Trichoplusia ni.  相似文献   
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Our objectives were to identify and field test the sex pheromone of female Douglas-fir cone gall midge, Contarinia oregonensis (Diptera: Cecidomyiidae). Coupled gas chromatographic–electroantennographic detection (GC-EAD) analyses of pheromone extract revealed a single compound (A) that elicited responses from male antennae. Hydrogenation of pheromone extract, followed by renewed GC-EAD analysis, revealed a new EAD-active compound with chromatographic characteristics identical to those of tridecan-2-yl acetate on five fused silica columns (DB-5, DB-210, DB-23, SP-1000, and Cyclodex-B). Syntheses, chromatography, and retention index calculations of all possible tridecen-2-yl acetates suggested that the candidate pheromone A was a tridecadien-2-yl acetate with nonconjugated double bonds. Synthetic candidate pheromone component (Z,Z)-4,7-tridecadien-2-yl acetate (Z4Z7) cochromatographed with A on all analytical columns and elicited comparable antennal activity. In GC-EAD analyses that separated the enantiomers (Z,Z)-4,7-tridecadien-(S)-2-yl acetate (2S-Z4Z7) and (Z,Z)-4,7-tridecadien-(R)-2-yl acetate (2R-Z4Z7) with baseline resolution, only 2S-Z4Z7 as a component in a racemic standard or in pheromone extract elicited antennal responses. In Douglas-fir seed orchards, sticky traps baited with 2S-Z4Z7 captured male C. oregonensis, whereas 2R-Z4Z7 was behaviorally benign. Comparable catches of males in traps baited with racemic Z4Z7 (50 g) or virgin female C. oregonensis suggested that synthetic pheromone baits could be developed for monitoring C. oregonensis populations in commercial Douglas-fir seed orchards.  相似文献   
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介绍了无线传感网络技术及发展、ZigBee PRO解决方案、以无线传感器网络IP为基础的解决方案的演变.在此基础上,探讨了ZigBee IP规范的细节和用途、使用ZigBee IP的设备实现,以及新的ZigBeeSmart Energy 2.0 IP协议栈的使用.  相似文献   
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