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1.
Annette L. West Louise V. Michaelson Elizabeth A. Miles Richard P. Haslam Karen A. Lillycrop Ramona Georgescu Lihua Han Johnathan A. Napier Philip C. Calder Graham C. Burdge 《Lipids》2021,56(2):229-242
The phospholipid composition of lipoproteins is determined by the specificity of hepatic phospholipid biosynthesis. Plasma phospholipid 20:4n-6 and 22:6n-3 concentrations are higher in women than in men. We used this sex difference in a lipidomics analysis of the impact of endocrine factors on the phospholipid class and molecular species composition of fasting plasma from young men and women. Diester species predominated in all lipid classes measured. 20/54 Phosphatidylcholine (PtdCho) species were alkyl ester, 15/48 phosphatidylethanolamine (PtdEtn) species were alkyl ester, and 12/48 PtdEtn species were alkenyl ester. There were no significant differences between sexes in the proportions of alkyl PtdCho species. The proportion of alkyl ester PtdEtn species was greater in women than men, while the proportion of alkenyl ester PtdEtn species was greater in men than women. None of the phosphatidylinositol (PtdIns) or phosphatidylserine (PtdSer) molecular species contained ether-linked fatty acids. The proportion of PtdCho16:0_22:6, and the proportions of PtdEtn O-16:0_20:4 and PtdEtn O-18:2_20:4 were greater in women than men. There were no sex differences in PtdIns and PtdSer molecular species compositions. These findings show that plasma phospholipids can be modified by sex. Such differences in lipoprotein phospholipid composition could contribute to sexual dimorphism in patterns of health and disease. 相似文献
2.
Field surveys of a series of conjugated diunsaturated straight-chain primary alcohols, acetates, and aldehydes (dienes), including the 3,5-dode-cadienyl, 8,10-dodecadienyl, 3,5-tetradecadienyl, 8,10-tetradecadienyl, 9,11-tetradecadienyl, and 10,12-tetradecadienyl primary alcohols, acetates, and most aldehydes, and the related monounsaturated straight-chain primary alcohols, acetates, and aldehydes (monoenes), including the 3-dodecadienyl alcohol and acetates, attracted the following species from the title families. Diene attractants have been demonstrated for at least onePhyllonorycter sp.,Chionodes lugubrella (Fabr.),Leptostales ferruminaria (Zell.),Drepana bilineata (Pack.),Pyrausta fodinalis (Led.),Notocelia purpurissatana Heinr.,Phaneta alterana Heinr. Monoene attractants were demonstrated forHedya separatana (Kft.),Cydia fletcherana (Kft.),Barbara mappana Free.,Ancylis burgessiana (Zell.),Ancylis nubeculana Clem.,Evippe prunifoliella Cham.,Phlyctaenia coronata tertialis (Gn.), aChionodes sp., a Gelechiidae sp., and an unidentifiedPhyllonorycter sp. Replicated field experiments showed attraction-inhibition relationships for most species. Electroantennagram data are presented forLeptostales ferruminaria andDrepana bilineata. 相似文献
3.
D. M. Suckling R. W. Peck L. M. Manning L. D. Stringer J. Cappadonna A. M. El-Sayed 《Journal of chemical ecology》2008,34(12):1602-1609
Disruption of Argentine ant trail following and reduced ability to forage (measured by bait location success) was achieved
after presentation of an oversupply of trail pheromone, (Z)-9-hexadecenal. Experiments tested single pheromone point sources and dispersion of a formulation in small field plots. Ant
walking behavior was recorded and digitized by using video tracking, before and after presentation of trail pheromone. Ants
showed changes in three parameters within seconds of treatment: (1) Ants on trails normally showed a unimodal frequency distribution
of walking track angles, but this pattern disappeared after presentation of the trail pheromone; (2) ants showed initial high
trail integrity on a range of untreated substrates from painted walls to wooden or concrete floors, but this was significantly
reduced following presentation of a point source of pheromone; (3) the number of ants in the pheromone-treated area increased
over time, as recruitment apparently exceeded departures. To test trail disruption in small outdoor plots, the trail pheromone
was formulated with carnuba wax-coated quartz laboratory sand (1 g quartz sand/0.2 g wax/1 mg pheromone). The pheromone formulation,
with a half-life of 30 h, was applied by rotary spreader at four rates (0, 2.5, 7.5, and 25 mg pheromone/m2) to 1- and 4-m2 plots in Volcanoes National Park, Hawaii. Ant counts at bait cards in treated plots were significantly reduced compared to
controls on the day of treatment, and there was a significant reduction in ant foraging for 2 days. These results show that
trail pheromone disruption of Argentine ants is possible, but a much more durable formulation is needed before nest-level
impacts can be expected.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
4.
S. M. Fitzpatrick D. Miller I. Weatherston J. N. McNeil 《Journal of chemical ecology》1985,11(2):207-215
Levels of benzaldehyde recovered from virginPseudaletia unipuncta (Haw.) males were not influenced by (1) the time hairpencils remained in the solvent (1-72 hr), (2) anesthetization or agitation of males prior to excision of hairpencils, or (3) the time (photophase or scotophase) that hairpencils were excised. Thus the interindividual variability observed is not a methodological artifact. Most males had similar concentrations in both hairpencils, although in some cases only one hairpencil contained pheromone. In one case, a male with partially extruded hairpencils had no benzaldehyde at all. Neither pupal weight nor hairpencil length proved to be reliable indicators of pheromone content.Contribution No. 373, Département de biologie, Université Laval. 相似文献
5.
Johan M. Thevelein 《Yeast (Chichester, England)》1994,10(13):1753-1790
6.
Tim T. Y. Wong D. O. McInnis Mohsen M. Ramadan Jon I. Nishimoto 《Journal of chemical ecology》1991,17(12):2481-2487
Laboratory-reared and wild adults of the melon fly,Dacus cucurbitae Coquillett, were tested for response to cue-lure at various ages. Virgin laboratory (4, 6, 8, 10, 12, and 14 days old) and wild (10, 12, 14, 16, 18, 20, and 22 days old) flies were released into outdoor field cages and trapped from 0800 until 1600 hr. Response of males to cue-lure increased with age and corresponded with sexual maturity for each strain. Females of both strains were relatively nonresponsive to cue-lure. Failure to eradicate in past male annihilation programs againstD. cucurbitae may be explained in part by the fact that only older males, which may have already mated with gravid females, respond to cue-lure. 相似文献
7.
对37名骨密度(BD)低下的飞行员(实验组)和BD正常的48名飞行员、100名地面人员(正常对照组)进行了BD和血清TT_3、TT_4、TSH IRMA、CT、PTH、E_2和T放射免疫测定。结果显示,实验组BD均值明显低于对照组(p<0.01),血清TT_3、TT_4、CT、E_2(女性)和T(男性)均值与对照组比较,大多数年龄存在着显著或非常显著差异(p<0.05或p<0.01)。同时对飞行人员BD与几种内分泌激素关系进行了探讨。 相似文献
8.
exo-brevicomin, a multifunctional pheromone of the mountain pine beetle,Dendroctonus ponderosae, was tested at release rates of 0.5 and 2.5 mg/day alone and in combination with the antiaggregation pheromone verbenone against unbaited controls. Significantly more lodgepole pinePinus contorta var.latifolia trees were attacked, and at higher densities, with both release rates ofexo-brevicomin than with all other treatments. Verbenone significantly reduced the response of mountain pine beetles toexo-brevicomin. Verbenone alone did not reduce the number of trees attacked by mountain pine beetle or the attack density when compared to the unbaited controls. 相似文献
9.
The behavioral and electrophysiological activity of a mimic [(Z,E)7,9,11-dodecatrienyl formate] of the major sex pheromone component [(Z,E) 9,11,13-tetradecatrienal] of carob moth was assessed. Wind-tunnel bioassays demonstrated that the formate was as effective as natural gland extracts, and significantly more effective than the trienal alone or than the trienal blended with two minor pheromone components, in evoking source contact. Dispensers containing the formate were as effective as trienal-containing blend lures in attracting males when placed at the same dosage in traps in date gardens. Single-cell recordings showed that at least two olfactory neurons, differentiated by spike amplitude, are located in the long trichoid hairs on male carob moth antennae. Dose-response relationships indicated that puffs from cartridges loaded with at least 0.1 g of the formate or of the trienal were necessary to elicit spiking by either the small or the large-spiking cell within a sensillum. Cross-adaptation studies demonstrated that both compounds stimulated the same large-spiking cell. The frequencies of spikes evoked from the large cell when stimulated by emissions from 0.1-g, 1-g, or 10-g cartridges of either the formate or the trienal were not significantly different, suggesting that the formate is an effective mimic of the trienal at the antennal receptor cell level. 相似文献
10.
本文研究移动机器人三维空间路径规划问题,针对三维空间的复杂地形特点,提出了一种基于改进蚁群算法的路径规划算法。文中首先描述了一种简单有效的环境建模方法,然后给出了算法在信息素呈现、路径点选取、信息素更新以及启发式函数设计等方面的改进方法。仿真结果证明了算法的可行性和可靠性。 相似文献