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1.
This study aimed to evaluate the effect of simulated training strategies on performance potential in elite short-track speed skaters. Training load and field-based criterion performances from fifteen athletes (10 males, 5 females) were collected over a 3-month training period and the relationship between training loads and performance was computed with a variable dose-response model using a genetic algorithm. Individual simulations of tapers preceded or not preceded by an overload training (OT) were assessed. We obtained a significant correlation between actual and modelled performances (R2 = 0.76 ± 0.07). Regarding model parameters, no significant difference was found between males and females but the time to recover performance tended to be lower in females. Simulations in which the taper parameters were free highlighted that an exponential or a step taper were the most effective for increasing performance compared to a linear taper (p < 0.05). Optimal exponential taper duration after OT was 10.7 ± 2.4d and the optimal load reduction was 75.9 ± 3.7%. OT intensity had the greatest influence on the predicted performance, followed by OT duration, taper decay, and to a lesser extent load reduction during taper and taper duration. Thus, a variable dose-response systems model allows the evaluation of different taper strategies and their potential effect on performance changes.  相似文献   
2.
Historically, disaster response efforts have focused primarily on basic physical survival and safety—addressing medical emergencies and ensuring adequate shelter and supplies of food and water. However, in addition to physical survival, relief efforts must also consider strategies to promote emotional healing and psychological well-being. In particular, those who intervene must consider the acceptability of intervention strategies, taking into account survivors' cultural background, religious customs, and spiritual beliefs. This article offers recommendations to better align school-based therapeutic interventions with children's religious and spiritual beliefs.  相似文献   
3.
Emerging paradigms of attack challenge enterprise cybersecurity with sophisticated custom-built tools, unpredictable patterns of exploitation, and an increasing ability to adapt to cyber defenses. As a result, organizations continue to experience incidents and suffer losses. The responsibility to respond to cybersecurity incidents lies with the incident response (IR) function. We argue that (1) organizations must develop ‘agility’ in their IR process to respond swiftly and efficiently to sophisticated and potent cyber threats, and (2) Real-time analytics (RTA) gives organizations a unique opportunity to drive their IR process in an agile manner by detecting cybersecurity incidents quickly and responding to them proactively. To better understand how organizations can use RTA to enable IR agility, we analyzed in-depth data from twenty expert interviews using a contingent resource-based view. The results informed a framework explaining how organizations enable agile characteristics (swiftness, flexibility, and innovation) in the IR process using the key features of the RTA capability (complex event processing, decision automation, and on-demand and continuous data analysis) to detect and respond to cybersecurity incidents as-they-occur which, in turn, improves their overall enterprise cybersecurity performance.  相似文献   
4.
研究旨在探讨一次不同抗阻训练方案对外周血CD4+和CD8+T淋巴细胞亚群迁移和凋亡的影响。通过实验法15名无训练经历的健康青年男性分别进行一次以促进肌肉肥大(H-RT组,方案:70%1RM,10RM,3组,组间间歇1.5 min)和以改善肌肉耐力(E-RT组,方案:60%1RM,15RM,3组,组间间歇1 min)为目的的抗阻训练方案。并于训练前、训练后即刻、训练后2 h和24 h利用流式细胞仪测定表面标志物CX3CR1和annexin V表达量检测CD4+、CD8+T淋巴细胞亚群迁移和凋亡(用阳性表达率表示)。得出以下数据:(1)CD4+T细胞在H-RT组运动后即刻和运动后24 h,annexin V和CX3CR1阳性表达率显著性升高(P<0.05)。E-RT组annexin V阳性表达率在运动后即刻降低(P<0.05),24 h显著性升高(P<0.05);CX3CR1阳性表达率仅在运动后即刻升高(P<0.05)。(2)CD8+T细胞在H-RT组和E-RT组运动后即刻和运动后24 h,annexin V和CX3CR1阳性表达率均显著性升高(P<0.05)。通过对以上数据的分析,研究得出以下结论:CD4+T淋巴细胞亚群对于急性抗阻训练的免疫反应存在运动方案依赖性。  相似文献   
5.
Recent advances have enabled diagnostic classification models (DCMs) to accommodate longitudinal data. These longitudinal DCMs were developed to study how examinees change, or transition, between different attribute mastery statuses over time. This study examines using longitudinal DCMs as an approach to assessing growth and serves three purposes: (1) to define and evaluate two reliability measures to be used in the application of longitudinal DCMs; (2) through simulation, demonstrate that longitudinal DCM growth estimates have increased reliability compared to longitudinal item response theory models; and (3) through an empirical analysis, illustrate the practical and interpretive benefits of longitudinal DCMs. A discussion describes how longitudinal DCMs can be used as practical and reliable psychometric models when categorical and criterion‐referenced interpretations of growth are desired.  相似文献   
6.
BackgroundOne-hour postprandial hyperglycemia is associated with increased risk of type 2 diabetes and cardiovascular disease. Physical activity (PA) has short-term beneficial effects on post-meal glucose response. This study compared the oral glucose tolerance test results of 3 groups of people with habitually different levels of PA.MethodsThirty-one adults without diabetes (age 25.9 ± 6.6 years; body mass index 23.8 ± 3.8 kg/m2; mean ± SD) were recruited and divided into 3 groups based on self-reported PA volume and intensity: low activity < 30 min/day of moderate-intensity activity (n = 11), moderately active ≥ 30 min/day of moderate-intensity PA (n = 10), and very active ≥ 60 min/day of PA at high intensity (n = 10). Participants completed an oral glucose tolerance test (50 g glucose) with capillary blood samples obtained at baseline, 15 min, 30 min, 45 min, 60 min, 90 min, and 120 min post-ingestion.ResultsThere were no significant differences between groups for age or body fat percentage or glycated hemoglobin (p > 0.05). The groups were significantly different in terms of baseline glucose level (p = 0.003) and, marginally, for gender (p = 0.053) and BMI (p = 0.050). There was a statistically significant effect of PA on the 1-h postprandial glucose results (p = 0.029), with differences between very active and low activity groups (p = 0.008) but not between the moderately active and low activity groups (p = 0.360), even when baseline glucose level and gender differences were accounted for. For incremental area under the curve there was no significant effect of activity group once gender and body fat percentage had been accounted for (p = 0.401). Those in the low activity group took 15 min longer to reach peak glucose level than those in the very active group (p = 0.012).ConclusionThe results suggest that high levels of PA have a beneficial effect on postprandial blood glucose profiles when compared to low and moderate levels of activity.  相似文献   
7.
ABSTRACT

The purpose of this study was to explore the respiratory response of acute interval and continuous exercise (CE) of low and high intensity. Fourteen recreational athletes (7 men and 7 women; VO2max = 35.7 ± 6.1 mlkg–1min–1) performed a bout of continuous and a bout of interval exercise (IE) both consisted of 5-min cycling at low intensity [80% of the power output (W) of the predetermined gas exchange threshold (GET) (80%WGET)] and 5-min cycling at high intensity {WGET plus the work rate corresponding to 50% of the difference between peak power output (PPO) at oxygen uptake (VO2max) test and the WGET [WGET + 0.50 Δ(PPO – WGET)]}. CE compared to IE induced significant higher heart rate and ventilation as well as significant higher levels of mouth occlusion pressure for 0.1 s (P0.1) (P < 0.05) during low and high intensities. Our results indicate that CE stimulates respiration more than IE when the exercise is performed at the same relative intensity.  相似文献   
8.
为探讨关键反应训练法对自闭症儿童主动提问技能的干预效果,采用单一被试研究中的跨行为多基线实验设计对一名自闭症儿童的物品主动提问、人物主动提问、地点主动提问等三个主动提问技能进行干预。研究结果表明关键反应训练法对自闭症儿童主动提问技能具有立即效果、维持效果和类化效果。为此,可以应用关键反应训练法对自闭症儿童进行训练。  相似文献   
9.
自上个世纪80年代开始,在国外战略管理研究领域兴起了一股关注企业间竞争攻击与反击互动的动态竞争研究浪潮。然而,国内对动态竞争的研究较晚,因此目前尚未形成对动态竞争理论与研究方法的系统认识。批判地回顾了动态竞争理论、方法与结论,揭示出各竞争要素之间的关系,并分析了动态竞争研究存在的局限和未来研究方向。  相似文献   
10.
气候变化问题与我国的应对战略   总被引:2,自引:0,他引:2  
全球气候变化是全球变化的核心问题,已经成为国际环境外交和国家可持续发展中的重大问题之一。我国政府对气候变化及其影响的重视与日俱增,已经确定了解决气候变化问题的基本原则,并初步确立了响应气候变化问题的立场和战略构想。本文从气候变化问题的由来、观测与研究的现状和问题、我国当前的政策和措施等方面,进一步思考应对气候变化影响和国际谈判的战略部署问题,并提出初步对策建议。  相似文献   
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