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41.
This article deals with relationships and marriages of the Tlingit with immigrants from the Russian Empire as well as with representatives of other European and non-European peoples during the period when Alaska belonged to the Russian Empire. Matrimonial relations existed in two variants: legal, sanctified by the church, and in the form of permanent extramarital cohabitation or casual relationships. The latter variant absolutely predominated. With this, there was a sharply reflected gender imbalance, since men absolutely predominated among the immigrants, and therefore Tlingit women emerged in the role of marriage partners in the overwhelming majority of cases. A directly opposite pattern was observed in Tlingit contacts with the Athapaskans and to some extent with the Eyak. Matrimonial connections exerted influence on the workings of the Russian colonization, stimulated growth in mixed populations, and facilitated gradual acculturation of the Tlingit, along with contributing to the expansion of their ethnic territory.  相似文献   
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Many people aim to change their lifestyle, but have trouble acting on their intentions. Behavioral economic incentives and related emotions can support commitment to personal health goals, but the related emotions remain unexplored. In a regret lottery, winners who do not attain their health goals do not get their prize but receive feedback on what their forgone earnings would have been. This counterfactual feedback should provoke anticipated regret and increase commitment to health goals. We explored which emotions were actually expected upon missing out on a prize due to unsuccessful weight loss and which incentive-characteristics influence their likelihood and intensity. Participants reported their expected emotional response after missing out on a prize in one of 12 randomly presented incentive-scenarios, which varied in incentive type, incentive size and deadline distance. Participants primarily reported feeling disappointment, followed by regret. Regret was expected most when losing a lottery prize (vs. a fixed incentive) and intensified with prize size. Multiple features of the participant and the lottery incentive increase the occurrence and intensity of regret. As such, our findings can be helpful in designing behavioral economic incentives that leverage emotions to support health behavior change.  相似文献   
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This study investigated a new direction for improving the decision making of populations at risk in the context of uncertain environmental events, such as volcanic hazards. According to the risk as feelings theory and dual process models, situations with certain outcomes do not necessarily require the use of affect heuristics (e.g., experienced feelings, anticipated emotions) as valid information in the decision‐making process. In the case of difficult decisions with moral dilemmas, certainty could even improve decisions. Thus, using an ecological design with various scenarios depicting upcoming volcanic hazards, we examined whether reducing the uncertainty of lethal threat by conveying certainty in an information campaign could influence decision making and promote a better quality of choice (correct application of the recommendations from the competent authorities). We focused specifically on two populations composed of local people living in the vicinity of an active volcano (Tungurahua volcano, Ecuador) and local scientists. We also examined whether a difficult decision involving a moral dilemma (e.g., leaving people behind so as not to jeopardize one's own life) potentiated this effect, compared to a less difficult situation without a dilemma. We demonstrated that, for local people facing a moral dilemma (difficult decision), the reduction of uncertainty of lethal threat involved a better application of the actual recommendations. These outcomes provided perspectives on improving the applications of the recommendations among local populations at risk in the context of a real risk exposure.  相似文献   
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Stress facilitates memory formation, but only when the stressor is closely linked to the learning context. These effects are, at least in part, mediated by corticosteroid hormones. Here we demonstrate that corticosterone rapidly facilitates synaptic potentiation in the mouse hippocampal CA1 area when high levels of the hormone and high-frequency stimulation coincide in time, but not when corticosterone is given either before or after repetitive stimulation. This effect could not be blocked by antagonists of the mineralocorticoid receptor and glucocorticoid receptor (spironolactone and RU 38486, respectively). These data provide a biological substrate for the important behavioral observation that stress and corticosteroid hormones can facilitate learning and memory processes.  相似文献   
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Many studies in animals and humans suggest that sleep facilitates learning, memory consolidation, and retrieval. Moreover, sleep deprivation (SD) incurred after learning, impaired memory in humans, mice, rats, and hamsters. We investigated the importance of sleep and its timing in an object recognition task in OF1 mice subjected to 6h SD either immediately after the acquisition phase (0-6 SD) or 6h later (7-12 SD), and in corresponding undisturbed controls. Motor activity was continuously recorded with infrared sensors. All groups explored two familiar, previously encountered objects to a similar extent, both at the end of the acquisition phase and 24h later during the test phase, indicating intact familiarity detection. During the test phase 0-6 SD mice failed to discriminate between the single novel and the two familiar objects. In contrast, the 7-12 SD group and the two control groups explored the novel object significantly longer than the two familiar objects. Plasma corticosterone levels determined after SD did not differ from time-matched undisturbed controls, but were significantly below the level measured after learning alone. ACTH did not differ between the groups. Therefore, it is unlikely that stress contributed to the memory impairment. We conclude that the loss of sleep and the activities the mice engaged in during the SD, impaired recognition memory retrieval, when they occurred immediately after acquisition. The delayed SD enabled memory consolidation during the 6h when the mice were allowed to sleep, and had no detrimental effect on memory. Neither SD schedule impaired object familiarity processing, suggesting that only specific cognitive abilities were sensitive to the intervention. Sleep may either actively promote memory formation, or alternatively, sleep may provide optimal conditions of non-interference for consolidation.  相似文献   
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