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The purpose of this study was to examine CHO ingestion on a cognitive task using a field-simulated time-trial (TT) under hypoxia in well-trained triathletes. Ten male triathletes (age: 22.1 ± 1.1 years; VO2max: 59.4 ± 1.4 ml/kg/min) participated in this double-blind/crossover/counter-balanced design study. Participants completed 3 TT trials: 1) normoxic placebo (NPLA; FiO2 = 20.9%), 2) hypoxic placebo (HPLA; FiO2 = 16.3%), and 3) hypoxic CHO (HCHO; 6% CHO provided as 2 ml/kg/15 min; FiO2 = 16.3%). During the TT, physiological responses (SpO2, HR, RPE, and blood glucose/lactate), cognitive performance, and cerebral haemodynamics were measured. Hypoxia reduced TT performance by ~3.5–4% (p < 0.05), but CHO did not affect TT performance under hypoxia. For the cognitive task, CHO slightly preserved exercise-induced cognitive reaction speed but did not affect response accuracy during hypoxic exercise. However, CHO did not preserve the decreased Hb-Diff (cerebral blood flow, CBF) and increased HHb in the prefrontal lobe (p < 0.05) during hypoxic exercise, and CHO failed to preserve hypoxia-suppressed prefrontal CBF and tissue oxygen saturation. In conclusion, the present study demonstrates that CHO is effective in sustaining reaction speed for a cognitive task but not promoting TT performance during hypoxic exercise, which would be important for strategy-/decision-making when athletes compete at moderate high-altitude.  相似文献   
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Despite the prevalence of fact-checking, little is known about who posts fact-checks online. Based upon a content analysis of Facebook and Twitter digital trace data and a linked online survey (N?=?783), this study reveals that sharing fact-checks in political conversations on social media is linked to age, ideology, and political behaviors. Moreover, an individual’s need for orientation (NFO) is an even stronger predictor of sharing a fact-check than ideological intensity or relevance, alone, and also influences the type of fact-check format (with or without a rating scale) that is shared. Finally, participants generally shared fact-checks to reinforce their existing attitudes. Consequently, concerns over the effects of fact-checking should move beyond a limited-effects approach (e.g., changing attitudes) to also include reinforcing accurate beliefs.  相似文献   
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One of the most commonly observed features of the organization of markets is that similar business enterprises cluster in physical space. In this paper, we develop an explanation for firm co-location in high-technology industries that draws upon a relational account of new venture creation. We argue that industries cluster because entrepreneurs find it difficult to leverage the social ties necessary to mobilize essential resources when they reside far from those resources. Therefore, opportunities for high tech entrepreneurship mirror the distribution of critical resources. The same factors that enable high tech entrepreneurship, however, do not necessary promote firm performance. In the empirical analyses, we investigate the effects of geographic proximity to established biotechnology firms, sources of biotechnology expertise (highly-skilled labor), and venture capitalists on the location-specific founding rates and performance of biotechnology firms. The paper finds that the local conditions that promote new venture creation differ from those that maximize the performance of recently established companies.  相似文献   
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Due to the decision of the Soviet Union and nearly all of its East European satellites to withdraw from the 1984 Los Angeles Summer Games, the communist media provided audiences in the Soviet bloc with few reports on the sporting events in the Olympic city. When Radio Free Europe and Radio Liberty, broadcasters funded by the US government, attempted to fill this ‘information gap’ by beaming coverage of the Los Angeles Games behind the Iron Curtain, the Soviet Union protested to the International Olympic Committee. They claimed, with a mixture of fact and fiction, that the Radios were tools of the American intelligence establishment and accused them of broadcasting ‘subversive’ propaganda to Eastern Europe and the USSR. Stirred into action by this Soviet manoeuvre, leading spokesmen for the Radios were joined by government officials, private citizens, US Olympic Committee members and the American media in a concerted attempt not only to defend the work of the broadcasters, but also to secure their press accreditation for Los Angeles.  相似文献   
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Recent research suggests that preschool children approach the task of word learning equipped with implicit biases that lead them to prefer some possible meanings over others. The noun-category bias proposes that children favor category relations when interpreting the meaning of novel nouns. In the series of experiments reported here, we develop a stringent test of the noun-category bias and reveal that it is present in children as young as 2 years of age. In each experiment, children participated in a 5-item match-to-sample task. Children were presented with a target item (e.g., a cow) and 4 choices, 2 of which belonged to the same superordinate category as the target (e.g., a fox and a zebra) and 2 of which were thematically related to the target (e.g., milk and a barn). In Experiment 1 we demonstrate that novel nouns prompt preschool children to attend to superordinate-level category relations, even in the presence of multiple thematic alternatives. In Experiment 2, we ascertain that the bias is specific to nouns; novel adjectives do not highlight superordinate category relations. In Experiment 3, we demonstrate the noun-category bias in 2-year-olds. The nature and utility of the noun-category bias are discussed.  相似文献   
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