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41.
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The balloon mania between 1783 and 1785 put an extraordinary strain on the Paris Academy of Sciences, threatening its status as the highest tribunal of European science. Faced with repeated royal directives and public frenzy, the Academy manoeuvred carefully to steer the research toward the hydrogen balloon and thereby to maintain its scientific superiority. Antoine-Laurent Lavoisier seized this moment when the promise of ‘the empire of airs’ brought science to the centre of public attention to push his theoretical reform for chemistry. He utilized the established protocol of the Academy and the resources of the Republic of Letters to broadly publicize his first decomposition of water in April 1784. Once he attained the publicity and the balloon fever began to cool, he staged a much more elaborate experiment for the experts in February 1785. Although this second, large-scale experiment cost much expense and effort, Lavoisier never published a full account. The differential care given to the two experiments can only be understood in their divergent rhetorical contexts. The written accounts in 1784 addressed the court of public opinion, while the exclusive performance in 1785 aimed at the court of experts to inaugurate the collaborative phase of the Chemical Revolution.  相似文献   
43.
Mapping mammalian synaptic connectivity has long been an important goal of neuroscientists since it is considered crucial for explaining human perception and behavior. Yet, despite enormous efforts, the overwhelming complexity of the neural circuitry and the lack of appropriate techniques to unravel it have limited the success of efforts to map connectivity. However, recent technological advances designed to overcome the limitations of conventional methods for connectivity mapping may bring about a turning point. Here, we address the promises and pitfalls of these new mapping technologies.  相似文献   
44.
Interleukin (IL)-17 is a pro-inflammatory cytokine that plays critical roles in host defense against extracellular bacteria and fungi and also in the pathogenesis of autoimmune diseases. While CD4+ TCRαβ+ T helper (Th) 17 cells are the best-described cellular source of IL-17, many innate-like T cells are in fact potent producers of IL-17. Given the increasing interest in therapeutic modulation of the IL-17 axis, it is crucial to better understand the cellular origins of IL-17 in various infection and diseases settings. While the diverse population of IL-17-producing T cells share many common characteristics, notable differences also exist. In this review, we discuss the heterogeneity of IL-17-producing T cell types focusing on their development, regulation, and function.  相似文献   
45.
This research forecasts peak call volume of a centralized after‐hours call center for rural electric cooperatives to help the call center determine staffing levels. A Gaussian copula is used to capture the dependence among non‐normal distributions. Using a centralized call center reduces costs by approximately 75% compared to having individual call centers at each cooperative. Adding cooperatives to the centralized call center is projected to further decrease costs per member. An out‐of‐sample forecasting exercise after the call center expanded validated the model's forecast that additional cooperatives could be added without a proportional increase in the peak number of calls. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
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Summary Serotonin and 5-hydroxyindoleacetic acid (5-HIAA) were measured in individual nuclei of rat hypothalamus and other brain areas using HPLC with electrochemical detection. 5-HIAA levels were first demonstrated in hypothalamic and some discrete brain areas. The 5-HIAA/5-HT ratio was highest in the n. caudatus putamen, high in the n. ventromedialis and lowest in the n. suprachiasmaticus.  相似文献   
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Adenyl cyclase stimulation by aspirin in rat gastric mucosa   总被引:1,自引:0,他引:1  
J C Mangla  Y M Kim  A A Rubulis 《Nature》1974,250(461):61-62
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50.
Following thyroidectomy, monoamine oxidase (MAO) activities toward tyramine decreased significantly by 20% in the nucleus periventricularis and the nucleus arcuatus among the 3 hypothalamic nuclei of the rat, while MAO activity toward serotonin decreased significantly by 10% only in the nucleus periventricularis. It is suggested that thyroidectomy induced selective changes on the multiple forms of MAO in the discrete circumventricular nuclei.  相似文献   
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