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Timm Schubert Corinna Gleiser Peter Heiduschka Christoph Franz Kerstin Nagel-Wolfrum Ayse Sahaboglu Nicole Weisschuh Gordon Eske Karin Rohbock Norman Rieger François Paquet-Durand Bernd Wissinger Uwe Wolfrum Bernhard Hirt Wibke Singer Lukas Rüttiger Ulrike Zimmermann Marlies Knipper 《Cellular and molecular life sciences : CMLS》2015,72(20):3953-3969
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Innate defence: evidence for memory in invertebrate immunity 总被引:2,自引:0,他引:2
Acquired immunity in vertebrates is characterized by immunological memory and specificity, whereas the innate defence systems of invertebrates are assumed to have no specific memory. Here we use a model system of a copepod, which is a minute crustacean, and a parasitic tapeworm to show that the success of reinfection depends on the antigenic resemblance between the consecutively encountered parasites. This finding indicates that an invertebrate defence system may be capable of specific memory. 相似文献
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Cues that reliably predict rewards trigger the thoughts and emotions normally evoked by those rewards. Humans and other animals will work, often quite hard, for these cues. This is termed conditioned reinforcement. The ability to use conditioned reinforcers to guide our behaviour is normally beneficial; however, it can go awry. For example, corporate icons, such as McDonald's Golden Arches, influence consumer behaviour in powerful and sometimes surprising ways, and drug-associated cues trigger relapse to drug seeking in addicts and animals exposed to addictive drugs, even after abstinence or extinction. Yet, despite their prevalence, it is not known how conditioned reinforcers control human or other animal behaviour. One possibility is that they act through the use of the specific rewards they predict; alternatively, they could control behaviour directly by activating emotions that are independent of any specific reward. In other words, the Golden Arches may drive business because they evoke thoughts of hamburgers and fries, or instead, may be effective because they also evoke feelings of hunger or happiness. Moreover, different brain circuits could support conditioned reinforcement mediated by thoughts of specific outcomes versus more general affective information. Here we have attempted to address these questions in rats. Rats were trained to learn that different cues predicted different rewards using specialized conditioning procedures that controlled whether the cues evoked thoughts of specific outcomes or general affective representations common to different outcomes. Subsequently, these rats were given the opportunity to press levers to obtain short and otherwise unrewarded presentations of these cues. We found that rats were willing to work for cues that evoked either outcome-specific or general affective representations. Furthermore the orbitofrontal cortex, a prefrontal region important for adaptive decision-making, was critical for the former but not for the latter form of conditioned reinforcement. 相似文献
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An attempt to produce antibodies to oxytocin and vasopressin 总被引:1,自引:0,他引:1
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In recent years evidence has been accumulating that personalities are not only found in humans but also in a wide range of other animal species. Individuals differ consistently in their behavioural tendencies and the behaviour in one context is correlated with the behaviour in multiple other contexts. From an adaptive perspective, the evolution of animal personalities is still a mystery, because a more flexible structure of behaviour should provide a selective advantage. Accordingly, many researchers view personalities as resulting from constraints imposed by the architecture of behaviour (but see ref. 12). In contrast, we show here that animal personalities can be given an adaptive explanation. Our argument is based on the insight that the trade-off between current and future reproduction often results in polymorphic populations in which some individuals put more emphasis on future fitness returns than others. Life-history theory predicts that such differences in fitness expectations should result in systematic differences in risk-taking behaviour. Individuals with high future expectations (who have much to lose) should be more risk-averse than individuals with low expectations. This applies to all kinds of risky situations, so individuals should consistently differ in their behaviour. By means of an evolutionary model we demonstrate that this basic principle results in the evolution of animal personalities. It simultaneously explains the coexistence of behavioural types, the consistency of behaviour through time and the structure of behavioural correlations across contexts. Moreover, it explains the common finding that explorative behaviour and risk-related traits like boldness and aggressiveness are common characteristics of animal personalities. 相似文献
28.
Repeated alcohol consumption leads to the development of tolerance, simply defined as an acquired resistance to the physiological and behavioural effects of the drug. This tolerance allows increased alcohol consumption, which over time leads to physical dependence and possibly addiction. Previous studies have shown that Drosophila develop ethanol tolerance, with kinetics of acquisition and dissipation that mimic those seen in mammals. This tolerance requires the catecholamine octopamine, the functional analogue of mammalian noradrenaline. Here we describe a new gene, hangover, which is required for normal development of ethanol tolerance. hangover flies are also defective in responses to environmental stressors, such as heat and the free-radical-generating agent paraquat. Using genetic epistasis tests, we show that ethanol tolerance in Drosophila relies on two distinct molecular pathways: a cellular stress pathway defined by hangover, and a parallel pathway requiring octopamine. hangover encodes a large nuclear zinc-finger protein, suggesting a role in nucleic acid binding. There is growing recognition that stress, at both the cellular and systemic levels, contributes to drug- and addiction-related behaviours in mammals. Our studies suggest that this role may be conserved across evolution. 相似文献
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扬子地块南缘元古代浊积岩源区风化特征和源岩性质的沉积地球化学记录 总被引:3,自引:0,他引:3
对扬子地台南缘元古代浊积岩的常量元素和微量元素地球化学研究表明,源区遭受了中等程度的风化作用影响,这种影响记录在碱金属和碱土金属元素的丰度与分布型式、蚀变化学指数(CIA)以及Th/U比值等方面。稀土元素的组成和配分型式、Th/Sc和La/Sc比值以及其他常量和微量元素之间的关系表明,沉积岩不具备成熟的再旋回沉积物的特征,其源岩主要为由酸性岩浆岩等长英质组分构成的古老上地壳,源岩曾受到了显著的壳内分异作用的影响。中元古界冷家溪群地层的源岩较新元古界板溪群合有较高的Co,Cr,Ni,Sc,V等基性组分,且基性的铁镁质成分主要反映在粘土级组分的沉积记录中。 相似文献
30.
Alessandro Cocchi Marco Cesare-Consumi Ryota Shimokura Franz Policardi 《华南理工大学学报(自然科学版)》2007,35(B10):21-24
针对意大利歌剧院进行研究,着重研究建筑设计对厅堂音质的影响.对两个剧院的常规音质参量进行了测量.这两座剧院是由同一建筑师Antonio Galli Bibiena设计的,分别是波仑亚的市立剧院和曼图亚的科学剧院.二者具有相当近似的形式,但尺寸不同,所用的材料也各畀,前者是用砖石建成,后者是用木料建成,因此在整修前采用了许多预应力钢筋混凝土结构.文中提供了不少数据并给出了对这些数据加以比较和分析的结果,特别是关于某些特征尺寸与扫频信号各可闻频率产生的空间听觉感受之间相关性的分析,以及若干有关材料和体型对IACC和EDT等音质参量的影响的思考. 相似文献