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271.
272.
Yorianta?Sasaerila Regine?Gries Gerhard?Gries Grigori?Khaskin Skip?King Stephen?Takács Hardi?) 《Chemoecology》2003,13(2):89-93
Summary. During peak calling activity by male oil palm bunch
moths, Tirathaba mundella Walker (Lepidoptera: Pyralidae), their
hairpencils, wings or entire body were extracted in hexane. Gas
chromatographic-electroantennographic detection (GC-EAD) analyses of
hair pencil extracts revealed four compounds that consistently elicited
responses from female antennae. The NMR spectrum of isolated compound 1,
and mass spectra and retention indices of compounds 1–4 suggested that
they were (3S,6S)-2,2,6-trimethyl-6-vinyl-tetrahydro-pyran-3-ol (1),
4-hydroxy-3-methoxy-benzaldehyde (2, vanillin),
6,10,14-trimethyl-2-pentadecanone (3), and
6,10,14-trimethyl-2-pentadecanol (4). Comparative GC and GC-MS analyses
of hair pencils extract and synthetic standards confirmed these
structural assignments. Moreover, comparative chromatography of
synthetic and hairpencil-isolated 1 on a Cyclodex-B column (which
separated the four stereoisomers with baseline resolution) revealed that
male T. mundella produce the SS-stereoisomer (SS-1). In field cage
bioassay experiments in Palembang, Indonesia, synthetic SS-1 and
vanillin in combination, but not singly, attracted female T. mundella.
SS-1 plus vanillin were as effective as male T. mundella in attracting
females. Compounds 3 and 4 did not enhance the blend's attractiveness.
Received October 11 2002; accepted March 14, 2003.
R1D="
Correspondence to: Gerhard Gries, email: gries@sfu.ca 相似文献
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Precision of Population Viability Analysis 总被引:5,自引:0,他引:5
Stephen P. Ellner #§ John Fieberg Donald Ludwig † Chris Wilcox‡ 《Conservation biology》2002,16(1):258-261
275.
Stephen A. Matthews 《Environmental geochemistry and health》1990,12(3):201-214
An attempt is made to synthesize the epidemiological literature and identify salient factors from the multitude of potential antecedents of gastric cancer, factors which to a greater or lesser degree create nonrandom variations in the distribution of the disease. Implicit in this approach is the notion that observation of spatial variations in the incidence of gastric cancer may lead to hypotheses relating to the biological, personal and physical environmental factors. An extensive bibliography accompanies the text.Formerly of the Department of Town Planning, University of Wales, College of Cardiff, PO Box 906, Cardiff CF1 3YN, Wales. 相似文献
276.
Summary Maternity and paternity uncertainty represent important costs to breeders among white-fronted bee-eaters (Merops bullockoides) in Kenya. Analysis of enzyme polymorphisms reveals that between 9% and 12% of all offspring are genetically unrelated to one or both of their putative parents. These bastards are the result of three different sources of parental uncertainty: Extrapair copulation, intraspecific egg parasitism, and quasi-parasitism (parasitism by a female who was fertilized by the male attending the parasitized nest). The first two represent costs to males, who rear offspring that are not genetically their own; the latter two produce the same costs for females. Genetic relatedness plays an important role in defining the social structure of M. bullockoides populations. In order to predict patterns of parental investment and the choice of recipients for helping behavior, one would like to know the relative frequency of maternity vs paternity uncertainty. The possible use of maximum likelihood techniques to separate the sources of non-kin is discussed. Unfortunately, the sample size of detected non-kin in the present study was not large enough to allow constructive use of the technique for bee-eaters. A comparison of estimates from biochemical and behavioral analyses indicates that both methods can produce misleading results. Behavioral data can be used to test underlying assumptions of biochemical analyses, and vice-versa. Used together, the two approaches reinforce one another and strengthen the reliability of conclusions drawn from either one alone. 相似文献
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Lúdvík Elíasson Stephen J. Turnovsky 《Journal of Environmental Economics and Management》2004,48(3):1018
We introduce a renewable resource sector into an endogenous growth model of a small economy, deriving the transitional dynamic equilibrium. The model generates a long-run equilibrium in which a resource sector of limited size can coexist with constant ongoing growth elsewhere. The key feature of the model is the allocation of labor between harvesting the resource and its use in the final output sector. This naturally generates the empirically observed negative relationship between resource abundance and growth. We examine both the dynamic and long-run responses of the economy to various shocks pertaining to technological production conditions and resource sector parameters. 相似文献