自适应模糊PID在无超调压力控制系统的应用

通过对压力控制系统自适应模糊PID控制器参数在线自整定,实现无超调控制．通过仿真,与常规PID控制器的相比较．说明此控制器能够改善系统的静、动态性能,增强系统适应能力和鲁棒性．     

试论篮球裁判员临场执法中心理调控的分析与对策

通过调查问卷和走访、咨询部分篮球界专家,结果发现裁判员在临场中的判罚尺度和准确性与裁判员的心理有直接的关系。裁判员的心理变化受到临场执法经验不足、篮球规则裁判法的掌握程度、情绪不稳定、自信心不足、职业道德等问题的影响,本文试对此进行分析并探究对策,希望能为今后篮球裁判员在执法中提高心理调控能力提供参考依据。     

优秀运动员竞技心理障碍分析及对策探讨

采取文献检索和调查访谈等方法分析了优秀运动员竞技心理素质的重要性、竞技心理障碍的表现及成因,探讨了排除竞技心理障碍的对策。     

不凝结气体对蒸汽浸没射流压力振荡的影响

通过实验研究不凝结气体（空气）对蒸汽浸没射流压力振荡特性的影响。结果表明：不凝结气体存在时压力振荡强度比纯蒸汽浸没射流时明显减小。随空气质量分数的增加,压力振荡峰值的位置沿轴向后移。过冷水温低于45℃时,峰值随空气质量分数的增加而增大;高于50℃时,随空气质量分数的增加而减小;水温在45~50℃之间时,峰值大致相同。压力振荡主频随空气质量分数、蒸汽质量流率和过冷水温度的增加而减小。     

大学生体质量指数（BMI)对血压水平的影响简

目的：探讨大学生人群血压水平与体质量指数（BMI）的相关性.方法：收集广州市6所高校大二学生共6225例的个人资料,对其体重、身高、体质量（BMI）、收缩压（SBP）、舒张压（DBP）进行统计学分析,同时对超重肥胖学生采用运动干预措施.结果：肥胖组SBP与DBP分别为（134.2±15.32）mmHg （88.54±9.21） mmHg,超重组SBP与DBP分别为（121.6±12.54） mmHg、（81.63±8.45）mmHg,体质量正常组SBP与DBP分别为（114.6±11.28） mmHg、（72.31±8.11） mmHg,低体质量组SBP与DBP分别为（102.3±10.35） mmHg、（67.21±8.22） mmHg,两两比较具有统计意义差异（P＜0.05）.对体重肥胖组学生进行有氧运动干预后发现,肥胖组学生BMI、SBP、DBP显著低于干预前,差异有统计学意义（P＜0.05）.经单因素分析可知,BMI与SBP、DBP呈正相关,与性别、年龄、入学时间无相关性.结论：大学生血压随着BMI的升高而升高,体检过程中可将BMI偏高作为预测肥胖大学生高血压的指标之一;通过对肥胖学生进行有氧运动干预可有效控制学生的血压水平.     

Wearable skin-like optoelectronic systems with suppression of motion artifacts for cuff-less continuous blood pressure monitor

According to the statistics of the World Health Organization, an estimated 17.9 million people die from cardiovascular diseases each year, representing 31% of all global deaths. Continuous non-invasive arterial pressure (CNAP) is essential for the management of cardiovascular diseases. However, it is difficult to achieve long-term CNAP monitoring with the daily use of current devices due to irritation of the skin as well as the lack of motion artifacts suppression. Here, we report a high-performance skin-like optoelectronic system integrated with ultra-thin flexible circuits to monitor CNAP. We introduce a theoretical model via the virtual work principle for predicting the precise blood pressure and suppressing motion artifacts, and propose optical difference in the frequency domain for stable optical measurements in terms of skin-like devices. We compare the results with the blood pressure acquired by invasive (intra-arterial) blood pressure monitoring for >1500 min in total on 44 subjects in an intensive care unit. The maximum absolute errors of diastolic and systolic blood pressure were ±7/±10 mm Hg, respectively, in immobilized, and ±10/±14 mm Hg, respectively, in walking scenarios. These strategies provide advanced blood pressure monitoring techniques, which would directly address an unmet clinical need or daily use for a highly vulnerable population.     

Acute cardiovascular responses to interval exercise: A systematic review and meta-analysis

ABSTRACT

Interval exercise training is increasingly recommended to improve health and fitness; however, it is not known if cardiovascular risk is different from continuous exercise protocols. This systematic review with meta-analyses assessed the effect of a single bout of interval exercise on cardiovascular responses that indicate risk of cardiac fibrillation and infarction compared to continuous exercise. Electronic databases Medline, CINAHL, Embase, Scopus and Cochrane were searched. Key inclusion criteria were: (1) intervals of the same intensity and duration followed by a recovery period and (2) reporting at least one of blood pressure, heart rate variability, arterial stiffness or function. Cochrane Risk of Bias tool and GRADE approach were used. Meta-analyses found that systolic blood pressure responses to interval exercise did not differ from responses to continuous exercise immediately (MD 8 mmHg [95% CI ?32, 47], p = 0.71) or at 60 min following exercise (MD 0 mmHg [95% CI ?2, 1], p = 0.79). However, reductions in diastolic blood pressure and flow-mediated dilation with interval exercise were observed 10–15 min post-exercise. The available evidence indicates that interval exercise does not convey higher cardiovascular risk than continuous exercise. Further investigation is required to establish the safety of interval exercise for clinical populations.     

我国冬季两项优秀运动员站立和行走足平衡能力研究

通过Footscan足底压力步态分析系统测试我国冬季两项优秀运动员站立和行走时足底压力分布并进行分析讨论。结果表明，运动员赤足站立的平衡能力高于穿鞋，双脚站立时闭眼稳定能力高于睁眼，单脚站立时左脚好于右脚；赤足行走支撑足足底压力时间曲线具有双峰特征、压力中心在横向摆动幅度较小；大部分运动员在足中部支撑阶段出现足内、外翻现象，建议教练指导队员加以注意并选用适合的鞋或添加鞋垫，增加足背屈时对应肌腱、韧带专向力量的练习，减少行走时足内外翻情况的出现，避免身体损伤出现。     

运动训练对自发性高血压大鼠心肌细胞凋亡蛋白表达的影响

目的:研究运动训练对SHR心肌细胞中HSP-72、Bcl-2和蛋白激酶β(PKB)、Bax、糖原合成激酶-3(GSK-3)的影响,以探讨其对运动引起心肌细胞凋亡的作用。方法:以SHR大鼠中等强度训练为实验模型,采用Western bloting技术检测了大鼠心肌细胞中调控蛋白HSP-72、Bcl-2和蛋白激酶β(PKB)、Bax、糖原合成激酶-3(GSK-3)的表达。结果:长期中等强度训练可以提高心肌细胞中抑凋亡蛋白HSP-72、Bcl-2和蛋白激酶β(PKB)的表达,凋亡蛋白Bax、糖原合成激酶-3(GSK-3)表达显著降低,Bcl-2/Bax的表达没有显著变化,从而抑制心肌细胞的凋亡。结论:心肌细胞中HSP-72、Bcl-2和蛋白激酶β(PKB)、Bax、糖原合成激酶-3(GSK-3),Bcl-2/Bax在运动后的不同表达对心肌细胞凋亡的发生有明显的抑制作用。     

4周下肢间歇负压干预对优秀赛艇运动员心率变异性和儿茶酚胺的影响

目的探讨下肢间歇负压干预对赛艇运动员心率变异性(HRV)相关指标和儿茶酚胺的影响。方法将国家赛艇队的14名运动员分为试验组和对照组,试验组运动员每周用间歇负压干预5 d,持续4周,对照组无其他干预方式。试验期间均对2组运动员进行HRV相关指标和儿茶酚胺的测试。结果试验前2组运动员各指标均无统计学差异。开始干预后2组的变化如下:①在时域指标中,试验组正常窦性R-R间期标准差(SDNN)在第3周时高于对照组(P<0.05)。②在频域指标中,试验组高频(HF)值在第2周和第3周时高于对照组(P<0.05),而其高频与低频比(LF/HF)在第1、3和4周时低于对照组(P<0.05)。③2组儿茶酚胺组内、组间比较均无统计学差异,但试验组儿茶酚胺下降程度比对照组高。结论 4周的间歇负压干预对运动员自主神经系统功能的恢复有明显促进作用,对儿茶酚胺的分泌也具有抑制趋势;这有利于降低运动员心脏负荷,促进运动后的生理恢复。