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This study involves the application of bond graphs to the generation of heat by cells in brown adipose tissue. In the first portion of this paper, data are presented to show the types of signals that can be measured at several sites in the system controlling thermogenesis—signals travelling from the brain to the tissue as well as signals over a feedback pathway from spinal cord temperature receptors back to the brain. Bond graphs are developed for several components of the system with an emphasis being placed on graphs describing the alternative mechanisms proposed for cellular energy conversion. The power flow is calculated using ENPORT for one mechanism for different values of plasma membrane resistance.  相似文献   
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The aim of this study was to examine the effects of active versus passive recovery on blood lactate disappearance and subsequent maximal performance in competitive swimmers. Fourteen male swimmers from the University of Virginia swim team (mean age 20.3 years, s= 4.1; stature 1.85 m, s= 2.2; body mass 81.1 kg, s= 5.6) completed a lactate profiling session during which the speed at the lactate threshold (V(LT)), the speed at 50% of the lactate threshold (V(LT.5)), and the speed at 150% of the lactate threshold (V(LT1.5)) were determined. Participants also completed four randomly assigned experimental sessions that consisted of a 200-yard maximal-effort swim followed by 10 min of recovery (passive, V(LT.5), V(LT), V(LT1.5)) and a subsequent 200-yard maximal effort swim. All active recovery sessions resulted in greater lactate disappearance than passive recovery (P < 0.0001 for all comparisons), with the greatest lactate disappearance associated with recovery at V(LT) (P= 0.006 and 0.007 vs. V(LT.5) and V(LT1.5) respectively) [blood lactate disappearance was 2.1 mmol l(-1) (s= 2.0), 6.0 mmol l(-1) (s=2.6), 8.5 mmol l(-1) (s= 1.8), and 6.1 mmol l(-1) (s= 2.5) for passive, V(LT.5), V(LT), and V(LT1.5) respectively]. Active recovery at VLT and V(LT1.5) resulted in faster performance on time trial 2 than passive recovery (P=0.005 and 0.03 respectively); however, only active recovery at V(LT) resulted in improved performance on time trial 2 (TT2) relative to time trial 1 (TT1) [TT2- TT1: passive +1.32 s (s= 0.64), V(LT.5) +1.01 s (s= 0.53), V(LT) -1.67 s (s= 0.26), V(LT1.5) -0.07 s (s = 0.51); P < 0.0001 for V(LT)). In conclusion, active recovery at the speed associated with the lactate threshold resulted in the greatest lactate disappearance and in improved subsequent performance in all 14 swimmers. Our results suggest that coaches should consider incorporating recovery at the speed at the lactate threshold during competition and perhaps during hard training sessions.  相似文献   
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The Isles of Wonder, the 2012 London Olympic Games Opening Ceremony, was viewed by a record global audience either live or through a range of electronic, social, and print media. British newspaper discourses provided reflection of the mega-sporting event as a ‘second-order’ construction, which gave readers an opportunity to reflexively decide what Britishness had come to represent. Theoretical insights about British identity were drawn from Anderson’s (1983 Anderson, B. 1983. Imagined Communities. New York: Verso. [Google Scholar]) concept of the nation as an ‘imagined community’, Tajfel and Turner’s (1986 Tajfel, H., and J. Turner. 1986. “The Social Identity Theory of Intergroup Behavior.” In Psychology of Intergroup Relations, edited by S. Worchel and W. G. Austin, 724. 2nd ed. Chicago: Nelson Hall Publishers. [Google Scholar]) social identity theory, and Edmunds and Turner’s (2001 Edmunds, J., and B. S. Turner. 2001. “The Re-Invention of a National Identity? Women and Cosmopolitan Englishness.” Ethnicities 1 (1): 83108.[Crossref] [Google Scholar]) juxtaposition of benign and malign nationalism. Our qualitative textual analysis revealed that although at times complex, contested, and contradictory, the narratives generally linked the internationalism of the Olympics with a progressive, benign version of Britishness that was still ‘great’. Underpinned by the aspirational New Jerusalem theme, the narratives generally acclaimed the Isles of Wonder as Britain’s first gold medal of the Games.  相似文献   
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