摘要：In this paper, we propose a new approach to the test of elliptical symmetry based on theprojection pursuit (P.P.) technique, the number-theoretic method, skewness and kurtosis. Thelimiting null distributions of the new statistics are derived. The powers of the tests against sixalternatives are calculated by simulation, which shows that the new ***'s are acceptable.

摘要：The impact of the adaptive cruise control（ ACC）system on improving fuel efficiency is evaluated based on the vehicle-specific power. The intelligent driver model was first modified to simulate the ACC system and it was calibrated by using empirical traffic data. Then, a five-step procedure based on the vehicle-specific power was introduced to calculate fuel efficiency. Five scenarios with different ACC ratios were tested in simulation experiments, and sensitivity analyses of two key ACC factors affecting the perception-reaction time and time headway were also conducted. The simulation results indicate that all the scenarios with ACC vehicles have positive impacts on reducing fuel consumption. Furthermore, from the perspective of fuel efficiency, the extremely small value of the perception-reaction time of the ACC system is not necessary due to the fact that the value of 0.5 and 0.1 s can almost lead to the same reduction in fuel consumption. Finally, the designed time headway of the ACC system is also proposed to be large enough for fuel efficiency, although its small value can increase capacity. The findings of this study provide useful information for connected vehicles and autonomous vehicle manufacturers to improve fuel efficiency on roadways.

摘要：针对路网中交通检测器布设问题,同时考虑到各路段布设费用差异性、总成本约束与检测器故障情况及观测数据随机不确定性,根据误差传播规律,以降低综合布设费用和提高路段流量推算可靠性为目标,构建了多目标检测器优化布设模型.为验证数学模型的科学性有效性,运用Nguyen-Dupuis和Sioux-Fall网络进行算例对比分析,研究结果表明:通过优化求解算法可获取最佳检测器布设方案,降低了检测器配置费用、提升了路网流量估计质量,且满足全路段流量完整可观测性要求,其流量推算次数及误差累计能有效减少20%与19%,论证了该模型在中大型网络上的适用性和合理性;其设计主要基于网络自身拓扑结构和节点流量守恒方程,不需要历史交通信息及路径信息,有效降低了计算复杂度.

摘要：Anterior cruciate ligament （ACL） injuries are common in soccer. Understanding ACL loading mechanisms and risk factors for ACL injury is critical for designing effective prevention programs. The purpose of this review is to summarize the relevant literature on ACL loading mechanisms, ACL injury risk factors, and current ACL injury prevention programs for soccer players. Literature has shown that tibial anterior translation due to shear force at the proximal end of tibia is the primary ACL loading mechanism. No evidence has been found showing that knee valgus moment is the primary ACL loading mechanism. ACL loading mechanisms are largely ignored in previous studies on risk factors for ACL injury. Identified risk factors have little connections to ACL loading mechanisms. The results of studies on ACL injury prevention programs for soccer players are inconsistent. Current ACL injury prevention programs for soccer players are clinically ineffective due to low compliance. Future studies are urgently needed to identify risk factors for ACL injury in soccer that are connected to ACL loading mechanisms and have cause-and-effect relationships with injury rate, and to develop new prevention programs to improve compliance.

摘要：动态治疗方案(Dynamic treatment regimens,DTRs)是一种序贯决策规则,是根据每个患者随时间变化而变化的特征和先前观察到的中间结果而量身定制的临床决策。精神障碍具有慢性和复杂性的特点,精神障碍患者具有异质性特点。这就要求随时间推移,根据个体对治疗反应的不同而分析出最佳的治疗方案,并动态地应用到患者之后的治疗中。多重方案随机序贯试验(Sequential Multiple Assignment Randomized Trial,SMARTs)的设计可以估计DTRs的治疗效应。SMARTs收集到大量的个体化变量和中间结果,在此基础上应用已有的现代统计工具可以优化DTRs。这些统计方法也可为今后的SMARTs研究设计推荐量身定制的变量。本文通过两个精神卫生研究案例介绍了DTRs和SMARTs,讨论了从SMARTs数据估算出最佳DTR的两种不同的计算机自动分析方法,并使用模拟数据演示这两种统计方法的性能。

摘要：目的:探究2型糖尿病(type 2 diabetes mellitus,T2DM)患者的人格画像,探讨其与用药依从性的关系及用药依从性的影响因素。方法:选取北京市通州区、顺义区中4个社区卫生服务中心所属的22个社区卫生服务站的T2DM患者作为研究对象,采用自行设计的问卷收集人口学信息,采用大五人格量表简式版收集人格信息,运用潜在剖面分析探究人格画像。采用用药依从性量表评估用药依从性,运用方差分析探究不同人格画像的用药依从性是否有差异,应用有序多分类Logistic回归探究用药依从性的影响因素。结果:751例T2DM患者被纳入研究,潜在剖面分析结果显示,本研究中的T2DM患者可分为4类人格画像,包括内敛稳定型(42.7%)、消极型(12.7%)、焦虑型(15.3%)和活泼负责型(29.3%),其中75例患者表示自己不用药也不打胰岛素,5例患者数据缺失,最终671例患者被纳入用药依从性的相关分析。方差分析结果显示,人格画像为焦虑型的患者其用药依从性得分(5.55±1.65)与消极型患者得分(5.94±1.53)差异无统计学意义(P=0.089),但显著低于内敛稳定型(6.17±1.46,P=0.001)和活泼负责型(6.09±1.65,P=0.004)。将人格画像为焦虑型和消极型的患者合并为焦虑消极型纳入有序多分类Logistic回归,结果显示,相比焦虑消极型患者,人格画像为活泼负责型、内敛稳定型是用药依从性好的保护因素(OR=1.567,95%CI:1.096~2.237;OR=1.774,95%CI:1.214~2.591),且受教育程度也影响患者的用药依从性。结论:基于大五人格理论,T2DM患者可分为4类人格画像,将焦虑型和消极型合并后的焦虑消极型是患者用药依从性差的独立危险因素;此外,受教育程度也是用药依从性的影响因素。

摘要：3-Hydroxymethyl-4-methyl-DCK(3,HMDCK)was discovered previously as a potent HIV non-nucleoside reverse transcriptase inhibitor(NNRTIs)(EC_(50):0.004 μM,TI:6225)with a novel mechanism of *** exerts anti-HIV activity by inhibiting the production of HIV-1 double-stranded viral DNA from a single-stranded DNA intermediate,rather than blocking the generation of single-stranded DNA from a RNA template,which is the mechanism of action of current HIV-1 RT ***,the insufficient metabolic stability of 3 limits its further clinical *** the current study,a series of ester prodrugs of 3 was designed and synthesized to explore the new drug candidates as *** L-alanine ester prodrug 10 exhibited desirable pharmacokinetic properties in vitro and in vivo and showed improved oral bioavailability of 26%in rat,and would be a potential clinical candidate as a new anti-AIDS drug.

摘要：回顾了近五年有机太阳能电池在电池材料和器件性能方面的研究进展.在材料方面,合成具有低带隙的化合物,使之与太阳光谱有更好的匹配,以提高对太阳光的吸收范围;在器件方面,通过使用异质结和纳米结构,使之在增加光吸收的同时保证激子的分离与有效迁移.有机聚合物太阳能电池是有机太阳能电池的发展方向,设计并合成具有低带宽和低HOMO能级的D-A型聚合物是提高其理论光能转化效率的关键.通过改进与提高电池的制作技术,充分挖掘新材料的潜力,将获得较大光能转换效率的有机太阳能电池.

摘要：背景：通常认为50％以上的冠心病患者缺乏任何常规危险因素(吸烟、糖尿病、高脂血症和高血压)。这一观念提示其他因素对冠心病具有重要作用，并引起人们对冠心病非传统危险因素和遗传因素的极大兴趣。目的：确定冠心病患者4种常规危险因素的流行状况。设计、地点和受试者：在2002～2003年，我们分析了过去10年中入选14个国际冠心病随机临床试验的122458例患者的资料，包括76716例ST段抬高心肌梗死、35527例不稳定性心绞痛／非ST段抬高心肌梗死和10215例进行经皮冠状动脉干预的患者。主要观察指标：冠心病患者每种常规危险因素的流行状况和数目，根据人选时的年龄在男性和女性之间进行比较。结果：冠心病患者中，4种常规危险因素中至少存在1种的比例，女性为84．6％，男性为80．6％。在较年轻(男性≤55岁，女性≤65岁)的患者以及大多数有不稳定性心绞痛或经皮冠状动脉干预的患者中，只有10％～15％的患者缺乏4种常规危险因素中的任何1种。这种情况很大程度上独立于性别、地区、试验入选标准或既往冠心病史。早发冠心病与男性吸烟有关，也与女性吸烟及糖尿病有关。在所有危险因素组合中，吸烟可将发生冠心病事件(试验入选)的年龄降低近10年。结论：与传统观念不同，80％～90％的冠心病患者有常规危险因素。虽然心脏病非传统危险因素和遗传因素研究是重要的，但是为了降低冠心病的流行，临床医学、公共健康政策和研究应重点强调4种常规危险因素及引起它们的生活方式。

摘要：目的:明确A组β溶血性链球菌感染是否会增加儿童发生自身免疫性神经精神异常综合征(PANDAS)的危险性。设计:前瞻性队列研究。