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51.
Jennifer L Graef Abbie E Smith Kristina L Kendall David H Fukuda Jordan R Moon Travis W Beck Joel T Cramer Jeffrey R Stout 《Journal of the International Society of Sports Nutrition》2009,6(1):18-7
Background
High-intensity interval training has been shown to be a time-efficient way to induce physiological adaptations similar to those of traditional endurance training. Creatine supplementation may enhance high-intensity interval training, leading to even greater physiological adaptations. The purpose of this study was to determine the effects of high-intensity interval training (HIIT) and creatine supplementation on cardiorespiratory fitness and endurance performance (maximal oxygen consumption (VO2PEAK), time-to-exhaustion (VO2PEAKTTE), ventilatory threshold (VT), and total work done (TWD)) in college-aged men. 相似文献52.
Lemuel W Taylor Colin D Wilborn Travis Harvey Jennifer Wismann Darryn S Willoughby 《Journal of the International Society of Sports Nutrition》2007,4(1):10-9
Background
The purpose of this study was to examine the effects of a functional coffee beverage containing additional caffeine, green tea extracts, niacin and garcinia cambogia to regular coffee to determine the effects on resting energy expenditure (REE) and hemodynamic variables. 相似文献53.
Elevated microbial tolerance to metals and antibiotics in metal-contaminated industrial environments 总被引:3,自引:0,他引:3
Stepanauskas R Glenn TC Jagoe CH Tuckfield RC Lindell AH McArthur JV 《Environmental science & technology》2005,39(10):3671-3678
To test the hypothesis that industrial metal contaminants select for microorganisms tolerant to unrelated agents, such as antibiotics, we analyzed metal and antibiotic tolerance patterns in microbial communities in the intake and discharge of ash settling basins (ASBs) of three coal-fired power plants. High-throughput flow-cytometric analyses using cell viability probes were employed to determine tolerances of entire bacterioplankton communities, avoiding bias toward culturable versus nonculturable bacteria. We found that bacterioplankton collected in ASB discharges were significantly more tolerant to metal and antibiotic exposures than bacterioplankton collected in ASB intakes. Optical properties of microorganisms collected in ASB discharges indicated no defensive physiological adaptations such as formation of resting stages or excessive production of exopolymers. Thus, it is likely that the elevated frequency of metal and antibiotic tolerances in bacterioplankton in ASB discharges were caused by shifts in microbial community composition, resulting from the selective pressure imposed by elevated metal concentrations or organic toxicants present in ASBs. 相似文献
54.
55.
Mike Spillane Ryan Schoch Matt Cooke Travis Harvey Mike Greenwood Richard Kreider Darryn S Willoughby 《Journal of the International Society of Sports Nutrition》2009,6(1):6-14
Numerous creatine formulations have been developed primarily to maximize creatine absorption. Creatine ethyl ester is alleged
to increase creatine bio-availability. This study examined how a seven-week supplementation regimen combined with resistance
training affected body composition, muscle mass, muscle strength and power, serum and muscle creatine levels, and serum creatinine
levels in 30 non-resistance-trained males. In a double-blind manner, participants were randomly assigned to a maltodextrose
placebo (PLA), creatine monohydrate (CRT), or creatine ethyl ester (CEE) group. The supplements were orally ingested at a
dose of 0.30 g/kg fat-free body mass (approximately 20 g/day) for five days followed by ingestion at 0.075 g/kg fat free mass
(approximately 5 g/day) for 42 days. Results showed significantly higher serum creatine concentrations in PLA (p = 0.007)
and CRT (p = 0.005) compared to CEE. Serum creatinine was greater in CEE compared to the PLA (p = 0.001) and CRT (p = 0.001)
and increased at days 6, 27, and 48. Total muscle creatine content was significantly higher in CRT (p = 0.026) and CEE (p
= 0.041) compared to PLA, with no differences between CRT and CEE. Significant changes over time were observed for body composition,
body water, muscle strength and power variables, but no significant differences were observed between groups. In conclusion,
when compared to creatine monohydrate, creatine ethyl ester was not as effective at increasing serum and muscle creatine levels
or in improving body composition, muscle mass, strength, and power. Therefore, the improvements in these variables can most
likely be attributed to the training protocol itself, rather than the supplementation regimen. 相似文献
56.
Carey M. Read Jr. Travis W. Knight Kenneth S. Allen 《Nuclear Engineering and Design》2011,241(12):5033-5038
Fast reactors containing heterogeneous minor actinide (MA) target rods are now being modeled. When studying transmutation in these rods, helium production from α-decay must be considered since it is produced in substantial quantities. This research utilized an innovative method to calculate gas production by modifying the CINDER90 depletion code used by MCNPX 2.6.0 to include helium production from α-decay. The modified CINDER90 code was verified using the ORIGEN-ARP module of SCALE6. It was tested using the Sodium-Cooled Heterogeneous Innovative Burner Reactor model created at the University of South Carolina. It is recommended that the modified version of the cinder.dat file be distributed in subsequent MCNPX 2.6.0 releases for use in fast reactor calculations using heterogeneous MA target rods since it includes helium production otherwise not available from the current version. 相似文献
57.
58.
Travis Eichhorn 《电子设计应用》2004,(12):112-116
电源的输入瞬变和负载瞬变是表示电源对供电电源和负载电流产生突变的响应能力。电源的输出响应能够反应出电源对于因输入和负载跃变而产生的各种频率谐波的衰减能力。 相似文献
59.
Two experiments examined the extent to which U.S. viewers' perceptions that Blacks face structural limitations to success, support for the death penalty, and culpability judgments could be influenced by exposure to racialized crime news. Participants were exposed to a majority of Black suspects, a majority of White suspects, unidentified suspects, and noncrime news stories. In addition, participants' prior news viewing was assessed. In Study 1, heavy news viewers exposed to unidentified perpetrators were less likely than heavy news viewers exposed to noncrime stories to perceive that Blacks face structural limitations to success. In addition, heavy news viewers exposed to unidentified perpetrators were more likely than heavy news viewers exposed to noncrime stories to support the death penalty. In Study 2, participants exposed to a majority of Black suspects were more likely than participants exposed to noncrime stories to find a subsequent race-unidentified criminal culpable for his offense. In addition, heavy news viewers were more likely to exhibit the above effect than light news viewers. The methodological and theoretical implications of these findings are discussed in light of chronic activation and the priming paradigm. 相似文献
60.
The inherited retinal dystrophies represent a large and heterogenous group of hereditary neurodegenerations, for many of which, the molecular defect has been defined. However, the mechanism of cell death has not been determined for any form of retinal degeneration. The retinal degeneration slow (rds-/-) mutation of mice is associated with nondevelopment of photoreceptor outer segments and gradual death of photoreceptor cell bodies, attributed to the absence of the outer segment protein rds/peripherin. Here, we examined the effects of a transgene encoding normal rds/peripherin that had integrated into the X-chromosome in male and female rds-/- mutant retinas. In 2-month-old transgenic males and homozygous-transgenic females on rds-/-, we observed virtually complete rescue of both the outer segment nondevelopment and photoreceptor degeneration. In contrast, hemizygous-transgenic rds-/- female littermates showed patchy distributions of the transgene mRNA, by in situ hybridization analysis, and of photoreceptor cells that contain outer segments. This pattern is consistent with random inactivation of the X-chromosome and mosaic expression of the transgene. Surprisingly, we observed significant photoreceptor cell loss in both transgene-expressing and nonexpressing patches in hemizygous female retinas. These observations were supported by nuclease protection analysis, which showed notably lower than predicted levels of transgene mRNA in retinas from hemizygous females compared with male and homozygous female littermates. This phenotype suggests an important component of non-cell-autonomous photoreceptor death in rds-/- mutant mice. These results have significance to both the etiology and potential treatment of human inherited retinal degenerations. 相似文献