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11.
Service providers may vary service quality depending on whether they work alone or provide the service simultaneously with a partner. The latter case resembles a prisoner's dilemma, in which one provider may try to reap the benefits of the interaction without providing the service. Here we present a game-theory model based on the marginal value theorem, which predicts that as long as the client determines the duration, and the providers cooperate towards mutual gain, service quality will increase in the pair situation. This prediction is consistent with field observations and with an experiment on cleaning mutualism, in which stable male-female pairs of the cleaner wrasse Labroides dimidiatus repeatedly inspect client fish jointly. Cleaners cooperate by eating ectoparasites off clients but actually prefer to cheat and eat client mucus. Because clients often leave in response to such cheating, the benefits of cheating can be gained by only one cleaner during a pair inspection. In both data sets, the increased service quality during pair inspection was mainly due to the smaller females behaving significantly more cooperatively than their larger male partners. In contrast, during solitary inspections, cleaning behaviour was very similar between the sexes. Our study highlights the importance of incorporating interactions between service providers to make more quantitative predictions about cooperation between species. 相似文献
12.
薇甘菊(Mikania micrantha H.B.K.)和五爪金龙(Ipomoea cairica (L.) Sweet)是近年来在华南地区造成严重入侵危害的2种恶性杂草.该文综述了它们与入侵性相关的生理生态特征以及化感作用.同时,根据2种植物在入侵机理方面的研究现状,分析和展望了后续研究中值得关注的研究方向. 相似文献
13.
Christian Feißt Carlo Pergola Marija Rakonjac Antonietta Rossi Andreas Koeberle Gabriele Dodt Marika Hoffmann Christina Hoernig Lutz Fischer Dieter Steinhilber Lutz Franke Gisbert Schneider Olof Rådmark Lidia Sautebin Oliver Werz 《Cellular and molecular life sciences : CMLS》2009,66(16):2759-2771
We previously showed that, in vitro, hyperforin from St. John’s wort (Hypericum perforatum) inhibits 5-lipoxygenase (5-LO), the key enzyme in leukotriene biosynthesis. Here, we demonstrate that hyperforin possesses
a novel and unique molecular pharmacological profile as a 5-LO inhibitor with remarkable efficacy in vivo. Hyperforin (4 mg/kg, i.p.) significantly suppressed leukotriene B4 formation in pleural exudates of carrageenan-treated rats associated with potent anti-inflammatory effectiveness. Inhibition
of 5-LO by hyperforin, but not by the iron-ligand type 5-LO inhibitor BWA4C or the nonredox-type inhibitor ZM230487, was abolished
in the presence of phosphatidylcholine and strongly reduced by mutation (W13A-W75A-W102A) of the 5-LO C2-like domain. Moreover,
hyperforin impaired the interaction of 5-LO with coactosin-like protein and abrogated 5-LO nuclear membrane translocation
in ionomycin-stimulated neutrophils, processes that are typically mediated via the regulatory 5-LO C2-like domain. Together,
hyperforin is a novel type of 5-LO inhibitor apparently acting by interference with the C2-like domain, with high effectiveness
in vivo. 相似文献