Acute effects of ingesting a commercial thermogenic drink on changes in energy expenditure and markers of lipolysis

Background  

To determine the acute effects of ingesting a thermogenic drink (Celsius, Delray Beach, FL) (TD) on changes in metabolism and lipolysis.     

Effects of β-alanine supplementation and high-intensity interval training on endurance performance and body composition in men; a double-blind trial

Background  

Intermittent bouts of high-intensity exercise result in diminished stores of energy substrates, followed by an accumulation of metabolites, promoting chronic physiological adaptations. In addition, β-alanine has been accepted has an effective physiological hydrogen ion (H⁺) buffer. Concurrent high-intensity interval training (HIIT) and β-alanine supplementation may result in greater adaptations than HIIT alone. The purpose of the current study was to evaluate the effects of combining β-alanine supplementation with high-intensity interval training (HIIT) on endurance performance and aerobic metabolism in recreationally active college-aged men.     

The effects of four weeks of creatine supplementation and high-intensity interval training on cardiorespiratory fitness: a randomized controlled trial

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 (VO_2PEAK), time-to-exhaustion (VO_2PEAKTTE), ventilatory threshold (VT), and total work done (TWD)) in college-aged men.     

The utility of event-based knowledge elicitation

The purpose of this investigation was to describe and evaluate an event-based knowledge elicitation technique. With this approach experts are provided with deliberate and controlled job situations, allowing investigation of specific task aspects and the comparison of expert responses. For this effort a videotape was developed showing an instructor pilot and student conducting a training mission. Various job situations were depicted in the video to gather information pertinent to understanding team situational awareness. The videotape was shown to 10 instructors and 10 student aviators in the community, and responses to the videotape were collected using a questionnaire at predetermined stop points. Consistent with expectations, the results showed that more experienced respondents (i.e., instructors) identified a richer database of cues and were more likely than students to identify strategies for responding to the situations depicted, providing some empirical evidence for the validity of the event-based technique. This method may serve as a useful knowledge elicitation technique, especially in the later stages of a job analysis when focused information is sought.     

A Study of the Fracture Behavior of Unindirectional Fiber- Reinforced Composite Using Coherent Gradient Sensing (CGS) Interferometry

The feasibility of using Coherent Gradient Sensing (CGS) interferometry for studying the fracture behavior of unidirectional fiber-reinforced composites is investigated in this paper. First, the solution for the deformation field surrounding the tip of a crack in an orthotropic material is summarized. Specifically, the most singular term in the asymptotic expansion is explicitly presented. Then, the quantities that relate to the CGS measurements are derived in terms of the spatial position, stress intensity factors, and material constants. Based on these results, synthetic CGS fringe patterns are plotted numerically, and the effects of material anisotropy and crack-tip mixity on the shape of CGS fringe pattern are investigated. In addition, a finite difference interpretation of CGS fringes caused by the finite spacing of the CGS diffraction gratings is taken into account in the simulation. Finally, the initiation fracture toughness and the subsequent resistance curve behavior of a particular unidirectional graphite/epoxy composite are measured using the CGS method. The optically measured stress intensity factors compare successfully to values obtained from the load measurements and the available analytical solutions. This revised version was published online in August 2006 with corrections to the Cover Date.     

Optimal allocation for estimating the mean of a bivariate polynomial

Suppose we wish to estimate the mean of some polynomial function of random variables from two independent Bernoulli populations, the parameters of which. rhemselves, are modeled as independent beta random variables. It. is assumed that the t.otal sample size for the experiment is fixed, but that the number of experimental units observed from each population may be random. This problem arises, ior example, when estimating the fault tolerance of a system by testing its compomentc individually. Using a decision theorebic approach, we seek to minimize the Bayes risk that arises from using a squared error loss function The Bayes estimator can lw detrmined in a straightforwardmanner, so the problem of optimal estimation rcduces. therefore, to a problem of optimallocatton of the samples between the two populatiorls. This can be solved via dynamic programming. Similar programming techniques are utilized to evaluate properties of a number of ad hoc allocation strategies that might also be collsidered for use in this problem.Two sample polynomials are analyzed along with a number of examples indicating the effects of different prior parameter settings. The effects of differences between prior pararueters used in the design and analysis stages of the experiment are also examined. For the polynomials considered, the adaptive strategies are found to be especially robust. We discuss computational techniques that facilitate such analyses by permitting rapid re-evaluation of strategies. Capabilities of this sort enrouragepeople to explorr designs more fully and to consider them from a number of different viewpuillts.     

Regional cerebral volume loss associated with verbal learning and memory in dementia of the Alzheimer type.

Twenty-seven research participants with dementia of the Alzheimer type were studied with the California Verbal Learning Test (D. C. Delis, J. H. Kramer, E. Kaplan, & B. A. Ober, 1987) and standardized volume measures of the mesial temporal cortical gray matter, neocortical gray matter, thalamus, and caudate nuclei, from magnetic resonance imaging. A pattern of atrophic brain changes in the mesial temporal lobes (MTL) and the thalamus, with relatively less severe atrophy in the neocortical gray matter, was associated with poorer learning of the word list. Similar patterns of brain atrophy were observed for measures of delayed recall and recognition hits. However, for delayed recall, neither contribution was statistically significant, and for recognition hits, MTL was only at the trend level for significance. These results provide evidence that the verbal memory deficit of Alzheimer's disease (AD) is associated not only with the mesial temporal limbic cortex, thought to be the site of earliest and most severe pathology in AD, but also with damage in the thalamus. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Structure-based design of inhibitors specific for bacterial thymidylate synthase

Thymidylate synthase is an attractive target for antiproliferative drug design because of its key role in the synthesis of DNA. As such, the enzyme has been widely targeted for anticancer applications. In principle, TS should also be a good target for drugs used to fight infectious disease. In practice, TS is highly conserved across species, and it has proven to be difficult to develop inhibitors that are selective for microbial TS enzymes over the human enzyme. Using the structure of TS from Lactobacillus casei in complex with the nonsubstrate analogue phenolphthalein, inhibitors were designed to take advantage of features of the bacterial enzyme that differ from those of the human enzyme. Upon synthesis and testing, these inhibitors were found to be up to 40-fold selective for the bacterial enzyme over the human enzyme. The crystal structures of two of these inhibitors in complex with TS suggested the design of further compounds. Subsequent synthesis and testing showed that these second-round compounds inhibit the bacterial enzyme at sub-micromolar concentrations, while the human enzyme was not inhibited at detectable levels (selectivities of 100-1000-fold or greater). Although these inhibitors share chemical similarities, X-ray crystal structures reveal that the analogues bind to the enzyme in substantially different orientations. Site-directed mutagenesis experiments suggest that the individual inhibitors may adopt multiple configurations in their complexes with TS.