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1.
Sports nutrition is a constantly evolving field with hundreds of research papers published annually. For this reason, keeping up to date with the literature is often difficult. This paper is a five year update of the sports nutrition review article published as the lead paper to launch the JISSN in 2004 and presents a well-referenced overview of the current state of the science related to how to optimize training and athletic performance through nutrition. More specifically, this paper provides an overview of: 1.) The definitional category of ergogenic aids and dietary supplements; 2.) How dietary supplements are legally regulated; 3.) How to evaluate the scientific merit of nutritional supplements; 4.) General nutritional strategies to optimize performance and enhance recovery; and, 5.) An overview of our current understanding of the ergogenic value of nutrition and dietary supplementation in regards to weight gain, weight loss, and performance enhancement. Our hope is that ISSN members and individuals interested in sports nutrition find this review useful in their daily practice and consultation with their clients.  相似文献   
2.
Rabbits were first given left cerebellar interpositus nucleus lesions followed by classical nictitating membrane (NM) conditioning using paired presentations of a tone conditioned stimulus (CS) and an air puff unconditioned stimulus (UCS). Multiple-unit hippocampal activity was monitored over the course of training. In rabbits with anterior interpositus lesions, the acquisition of learned responses and significant increases in training-related hippocampal activity were prevented when paired training was given to the left NM but not when training was switched to the right NM. Rabbits with lesions anterior to the interpositus or in surrounding cerebellar regions failed to show deficits in behavioral responding or hippocampal activity. These results indicate that acquisition of conditioning-related activity in the hippocampus depends on an intact interpositus nucleus of the cerebellum. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
3.
The advanced TALSPEAK process is a selective solvent extraction that utilizes 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (HEH[EHP]) to separate lanthanide elements from trivalent actinides, which are held back in the aqueous phase by N-hydroxylethyl-N,N’,N’-ethylenediamine triacetic acid (HEDTA) buffered by citric acid. Gamma irradiation of an experiment containing Eu(III) and Am(III) as representative lanthanide and actinide elements resulted in higher distribution ratios of both and separation factors which decreased in an exponential fashion with increasing dose. Analysis of the reagents showed that the HEDTA concentration also decreased in an exponential fashion, strongly suggesting that degradation was correlated with loss of separation selectivity. In contrast, the concentration of citrate was unaffected, and while the concentration of HEH[EHP] did decrease, its dose-dependent kinetic profile indicated that it was not limiting partitioning. A second set of experiments were conducted using a citrate concentration that was 7.5 X higher, with the expectation that citrate would protect the HEDTA by scavenging radiolytically formed OH radicals. HEDTA degradation was significantly mitigated at higher gamma doses, but the Eu-Am separation was worse than in the low citrate experiments, presumably because at the high citrate concentrations, the Eu-citrate complexes formed in abundances competitive with the Am complexes, and are more effectively held back in the aqueous phase.  相似文献   
4.
Metrics of success or impact in academia may do more harm than good. To explore the value of citations, the reported efficacy of treatments in ecology and evolution from close to 1,500 publications was examined. If citation behavior is rationale, i.e. studies that successfully applied a treatment and detected greater biological effects are cited more frequently, then we predict that larger effect sizes increases study relative citation rates. This prediction was not supported. Citations are likely thus a poor proxy for the quantitative merit of a given treatment in ecology and evolutionary biology—unlike evidence-based medicine wherein the success of a drug or treatment on human health is one of the critical attributes. Impact factor of the journal is a broader metric, as one would expect, but it also unrelated to the mean effect sizes for the respective populations of publications. The interpretation by the authors of the treatment effects within each study differed depending on whether the hypothesis was supported or rejected. Significantly larger effect sizes were associated with rejection of a hypothesis. This suggests that only the most rigorous studies reporting negative results are published or that authors set a higher burden of proof in rejecting a hypothesis. The former is likely true to a major extent since only 29 % of the studies rejected the hypotheses tested. These findings indicate that the use of citations to identify important papers in this specific discipline—at least in terms of designing a new experiment or contrasting treatments—is of limited value.  相似文献   
5.
This paper provides experimental validation of the digital first-order periodic error reduction scheme described by Chu and Ray. A bench-top setup of a single-pass, heterodyne Michelson interferometer, designed to minimize common error contributors such as Abbe, dead path and environment, is described. Linear, reciprocating motion generation is achieved using a parallelogram, leaf-type flexure. Periodic error amplitude is varied through independent rotation of a half wave plate and polarizer. Experimental results demonstrate that the correction algorithm can successfully attenuate first-order error to sub-nm levels for a wide range of frequency mixing conditions.  相似文献   
6.
For computer vision systems to operate in many real-world environments, processing must occur in real-time under dynamic conditions. An agent-based methodology offers an approach to increase flexibility and scalability to accommodate the demands of a real-time, dynamic environment. This paper presents an agent-based architecture that uses a utility optimization technique to guarantee that important vision tasks are fulfilled even under resource constraints. To ensure that the processing of vision tasks is both reliable and flexible, multiple behaviors are utilized to accomplish the vision application's requirements. A vision behavior consists of a grouping of vision algorithms and a set of service levels associated with these algorithms. Utility functions are adopted to evaluate the performance of all possible behaviors that can address the requirements of a vision application within resource constraints. The maximum overall utility corresponds to the optimal behavior. Two example systems using this model are presented to show the applicability of the architecture. Experimental results show that this agent-based architecture outperforms traditional non-agent-based approaches.  相似文献   
7.
The factor structure of the Brief Symptom Inventory-18 (BSI-18; L. R. Derogatis, 2000) was investigated in a sample of adult survivors of childhood cancer enrolled in the Childhood Cancer Survivor Study (CCSS; N = 8,945). An exploratory factor analysis with a randomly chosen subsample supported a 3-factor structure closely corresponding to the 3 BSI-18 subscales: Depression, Anxiety, and Somatization. Confirmatory factor analysis with structural equation modeling validated this 3-dimensional structure in a separate subsample, though an alternative 4-factor model also fit the data. Analysis of the 3-factor model showed consistent fit in male and female participants. Compared with available community-based norms, survivors reported fewer symptoms of psychological distress. Together, results support the hypothesized 3-dimensional structure of the BSI-18 and indicate the measure may be useful in assessing psychological distress in this growing population of cancer survivors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
8.
Editorial     
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9.
Compared responses on a checklist of distress behaviors to ratings of medical-procedure-related pain and anxiety by 29 male and 21 female 6–17 yr old cancer patients and 1 adult observer. Results show that children showed greater behavioral distress than adolescents only during the actual medical procedure; however, additional behaviors were observed that suggested that the checklist was age-biased and that the 2 age groups experienced an equal amount of stress. This assumption was supported by a measure of intensity, observer reports, and patient self-reports, which showed no differences between the 2 age groups. None of the measures showed any significant differences for sex or ethnic origin. Data show that children had less physical control and more emotional outbursts than adolescents during a stressful procedure. It is concluded that clinical research on pain and anxiety should incorporate both self-report and observer data. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
10.
The present study examined the referral patterns of 1,095 African, 2,168 Asian, 1,385 Hispanic, and 2,273 White Americans (18 years of age and older) in a public mental health system to determine whether group differences in help-seeking and referral patterns were related to participation in ethnic-specific versus mainstream programs. Results indicated that (a) ethnic minorities in both mainstream and ethnic-specific programs were more likely than Whites to have been referred by natural help-giving and lay referral sources (e.g., family or friends, health services, and social services) and (b) ethnic minorities in ethnic-specific programs were more likely than ethnic minorities in mainstream programs to have been referred by natural help-giving and lay referral sources if they were Asian and Hispanic Americans and self-referred if they were African Americans. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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