针对非原点最优的复杂优化问题(最优解不在坐标原点),提出了一种基于随机交叉-自学策略的教与学优化算法(teaching and learning optimization algorithm based on random crossover-self-study strategy,CSTLBO)。对标准教与学优化算...针对非原点最优的复杂优化问题(最优解不在坐标原点),提出了一种基于随机交叉-自学策略的教与学优化算法(teaching and learning optimization algorithm based on random crossover-self-study strategy,CSTLBO)。对标准教与学优化算法的“教阶段”和“学阶段”的空间扰动进行了几何解释,改进了原有的“教阶段”和“学阶段”,并引入随机交叉策略和“自学”策略来提高算法的全局寻优能力。通过使用20个Benchmark函数进行仿真,并与6种改进的教与学优化算法进行结果比较及Wilcoxon秩和检验分析,结果表明CSTLBO算法能有效避免陷入局部最优,具有良好的全局搜索能力,求解精度高,稳定性好。展开更多
OBJECTIVES: This study was designed to assess the impact of prevention of bradycardia with physiologic pacing on the severity of obstructive sleep apnea. BACKGROUND: Apneic episodes during sleep are associated with sl...OBJECTIVES: This study was designed to assess the impact of prevention of bradycardia with physiologic pacing on the severity of obstructive sleep apnea. BACKGROUND: Apneic episodes during sleep are associated with slowing of the heart rate during apnea and tachycardia with subsequent arousal. Patients with permanent pacemakers may have reduced episodes of sleep apnea when their pacemaker rate is set faster than their spontaneous nocturnal heart rate. METHODS: We conducted a prospective, randomized, single-blind crossover trial of temporary atrial pacing in obstructive sleep apnea to reduce the apnea hypopnea index(AHI). Fifteen patients(age 60± 13 years, 12 men) with moderate to severe obstructive sleep apnea(AHI 34± 14) underwent insertion of an externalized atrial permanent pacing system via the left subclavian vein. Patients underwent overnight respiratory sleep studies in hospital, during atrial pacing at 75 beats/min, and with pacing turned off. The order of pacing mode was randomized, with crossover the subsequent night to the other mode. Patients were blinded to pacing mode, and the analysis of sleep recordings was blind to pacing mode. RESULTS: Pacing was tolerated without complications in all patients. Overnight physiologic pacing did not affect the AHI(pacing 39± 21/h vs. control 42± 21/h, p=0.23, 95% confidence interval- 9.3 to 2.5 for difference), desaturation time(pacing 3.8± 6.0% vs. control 3.5± 4.3% , p=0.70), or the minimum SaO2(pacing 75± 10% vs. control 77± 11% , p=0.38). There was a borderline significant reduction in circulatory time with pacing(pacing 23.4± 3.2 s vs. control 25.5± 4.4 s, p=0.09). CONCLUSIONS: Temporary atrial pacing does not appear to improve respiratory manifestations of obstructive sleep apnea. Permanent atrial pacing in this patient population does not appear to be justified.展开更多
多效复方固定制剂(Polypill)可用于心血管疾病风险的一级预防,但其降低胆固醇和血压的疗效尚未确定。本研究入选年龄≥50岁,无心血管疾病的参与者,进行一项随机、双盲、安慰剂对照的交叉试验,探讨Polypill降低胆固醇和血压的疗效,并与...多效复方固定制剂(Polypill)可用于心血管疾病风险的一级预防,但其降低胆固醇和血压的疗效尚未确定。本研究入选年龄≥50岁,无心血管疾病的参与者,进行一项随机、双盲、安慰剂对照的交叉试验,探讨Polypill降低胆固醇和血压的疗效,并与已发表的单一组分药物的疗效进行比较。参与者每天傍晚上按随机顺序服用Polypill(氨氯地平2.5mg,氯沙坦25.0mg,氢氯噻嗪12.5mg和辛伐他汀40.0mg)12周或安慰剂12周。每12周结束之后,观察参与者血压和低密度脂蛋白胆固醇水平的变化。86名参与者中的84名完成了试验。服用Polypill参与者的平均收缩压降低了17.9mm Hg(95% CI 15.7～20.1),平均舒张压降低9.8mm Hg(95% CI 8.1～11.5),低密度脂蛋白胆固醇降低1.4mmol/L(95% CI 1.2～1.6),降低的百分比分别12%、11%、39%。这与以往已发表的结果一致(分别降低18.4、9.7mm Hg和1.4mmol/L)。总之,Polypill能够降低低密度脂蛋白胆固醇和血压至预期水平,对预防心脏病和脑卒中发生发展有重要作用。展开更多
文摘针对非原点最优的复杂优化问题(最优解不在坐标原点),提出了一种基于随机交叉-自学策略的教与学优化算法(teaching and learning optimization algorithm based on random crossover-self-study strategy,CSTLBO)。对标准教与学优化算法的“教阶段”和“学阶段”的空间扰动进行了几何解释,改进了原有的“教阶段”和“学阶段”,并引入随机交叉策略和“自学”策略来提高算法的全局寻优能力。通过使用20个Benchmark函数进行仿真,并与6种改进的教与学优化算法进行结果比较及Wilcoxon秩和检验分析,结果表明CSTLBO算法能有效避免陷入局部最优,具有良好的全局搜索能力,求解精度高,稳定性好。
文摘OBJECTIVES: This study was designed to assess the impact of prevention of bradycardia with physiologic pacing on the severity of obstructive sleep apnea. BACKGROUND: Apneic episodes during sleep are associated with slowing of the heart rate during apnea and tachycardia with subsequent arousal. Patients with permanent pacemakers may have reduced episodes of sleep apnea when their pacemaker rate is set faster than their spontaneous nocturnal heart rate. METHODS: We conducted a prospective, randomized, single-blind crossover trial of temporary atrial pacing in obstructive sleep apnea to reduce the apnea hypopnea index(AHI). Fifteen patients(age 60± 13 years, 12 men) with moderate to severe obstructive sleep apnea(AHI 34± 14) underwent insertion of an externalized atrial permanent pacing system via the left subclavian vein. Patients underwent overnight respiratory sleep studies in hospital, during atrial pacing at 75 beats/min, and with pacing turned off. The order of pacing mode was randomized, with crossover the subsequent night to the other mode. Patients were blinded to pacing mode, and the analysis of sleep recordings was blind to pacing mode. RESULTS: Pacing was tolerated without complications in all patients. Overnight physiologic pacing did not affect the AHI(pacing 39± 21/h vs. control 42± 21/h, p=0.23, 95% confidence interval- 9.3 to 2.5 for difference), desaturation time(pacing 3.8± 6.0% vs. control 3.5± 4.3% , p=0.70), or the minimum SaO2(pacing 75± 10% vs. control 77± 11% , p=0.38). There was a borderline significant reduction in circulatory time with pacing(pacing 23.4± 3.2 s vs. control 25.5± 4.4 s, p=0.09). CONCLUSIONS: Temporary atrial pacing does not appear to improve respiratory manifestations of obstructive sleep apnea. Permanent atrial pacing in this patient population does not appear to be justified.
文摘多效复方固定制剂(Polypill)可用于心血管疾病风险的一级预防,但其降低胆固醇和血压的疗效尚未确定。本研究入选年龄≥50岁,无心血管疾病的参与者,进行一项随机、双盲、安慰剂对照的交叉试验,探讨Polypill降低胆固醇和血压的疗效,并与已发表的单一组分药物的疗效进行比较。参与者每天傍晚上按随机顺序服用Polypill(氨氯地平2.5mg,氯沙坦25.0mg,氢氯噻嗪12.5mg和辛伐他汀40.0mg)12周或安慰剂12周。每12周结束之后,观察参与者血压和低密度脂蛋白胆固醇水平的变化。86名参与者中的84名完成了试验。服用Polypill参与者的平均收缩压降低了17.9mm Hg(95% CI 15.7～20.1),平均舒张压降低9.8mm Hg(95% CI 8.1～11.5),低密度脂蛋白胆固醇降低1.4mmol/L(95% CI 1.2～1.6),降低的百分比分别12%、11%、39%。这与以往已发表的结果一致(分别降低18.4、9.7mm Hg和1.4mmol/L)。总之,Polypill能够降低低密度脂蛋白胆固醇和血压至预期水平,对预防心脏病和脑卒中发生发展有重要作用。
