大学新生网络使用时间与网络成瘾的关系：有中介的调节模型

通过整群取样的方法选取北京市某所高校2250名大一新生为测查对象, 采用问卷方式探讨了大学新生网络使用时间、网络社交使用占网络使用总时间的比重、网络使用的背景性渴求以及网络成瘾程度之间的关系。基于网络使用满足的相关理论以及渴求的条件反射理论, 本研究构建了一个有中介的调节模型, 即网络社交使用比重在网络使用时间与网络成瘾之间起调节作用, 而且这一调节作用通过网络使用的背景性渴求这一中介变量得以实现。结果显示：(1)大学新生每周上网时间为13.58 ± 8.94小时, 网络社交使用占全部上网时间的比重为27.18 ± 18.15%; (2)网络使用时间、网络社交使用比重、网络使用背景性渴求与网络成瘾的五个维度及总分呈显著正相关; (3)网络使用时间以及网络社交使用比重均能够直接正向预测网络成瘾, 同时网络社交比重在网络使用时间预测网络成瘾这一关系中起调节作用, 即相比较少使用网络社交的被试, 较多使用网络社交的群体表现出更高的网络成瘾程度, 且网络使用时间对网络成瘾程度的预测作用相对较低; 而且网络社交比重的调节作用部分通过网络使用的背景性渴求这一中介变量实现。     

Children's (and Adults') Production Adjustments to Generic and Particular Listener Needs

Adults design utterances to match listeners' informational needs by making both “generic” adjustments (e.g., mentioning atypical more often than typical information) and “particular” adjustments tailored to their specific interlocutor (e.g., including things that their addressee cannot see). For children, however, relevant evidence is mixed. Three experiments investigated how generic and particular factors affect children's production. In Experiment 1, 4‐ to 5‐year‐old children and adults described typical and atypical instrument events to a silent listener who could either see or not see the events. In later extensions, participants described the same events to either a silent (Experiment 2) or an interactive (Experiment 3) addressee with a specific goal. Both adults and 4‐ to 5‐year‐olds performed generic adjustments but, unlike adults, children made listener‐particular adjustments inconsistently. These and prior findings can be explained by assuming that particular adjustments can be costlier for children to implement compared to generic adjustments.     

陆军初级指挥院校新学员潜在能力测验及其选拔模式的研究

针对陆军初级指挥院校在选材方面的现状,通过百名专家问卷调查,参阅国际现行的有关标准及我军多年来能力培养方面的研究成果．比照陆军初级指挥院校教学大纲所提出的能力培养要素及其要求,构建了陆军初级指挥院校新学员的选拔摸式,确立了淘汰标准。     

The effect of swinging the arms on muscle activation and production of leg force during ski skating at different skiing speeds

The study investigated the effects of arm swing during leg push-off in V2-alternate/G4 skating on neuromuscular activation and force production by the leg muscles. Nine skilled cross-country skiers performed V2-alternate skating without poles at moderate, high, and maximal speeds, both with free (SWING) and restricted arm swing (NOSWING). Maximal speed was 5% greater in SWING (P < 0.01), while neuromuscular activation and produced forces did not differ between techniques. At both moderate and high speed the maximal (2% and 5%, respectively) and average (both 5%) vertical force and associated impulse (10% and 14%) were greater with SWING (all P < 0.05). At high speed range of motion and angular velocity of knee flexion were 24% greater with SWING (both P < 0.05), while average EMG of m. biceps femoris was 31% lower (all P < 0.05) in SWING. In a similar manner, the average EMG of m. vastus medialis and m. biceps femoris were lower (17% and 32%, P < 0.05) during the following knee extension. Thus, swinging the arms while performing V2-alternate can enhance both maximal speed and skiing economy at moderate and, in particularly, high speeds.     

Walking in an environment of moving ground texture

The visual control of global body movements has mainly been studied in terms of the maintenance of balance. The present experiment examined the effect of moving visual surroundings on the speed of locomotion. A virtually boundless optical environment was generated by the projection of a dotted texture on the ground that was reflected on large vertical mirrors fixed along the walls of the room. Subjects' head velocity was recorded over a walking path of about 10 m along the projection surface. In the experimental sessions, the texture was animated and moved at different speeds in the same direction as the subject or in the opposite direction. In the control condition, the projected texture remained motionless and therefore appeared to pass by at the subjects' walking speed. The subjects' task was to maintain a constant walking speed as far as possible over the different conditions. Changes in walking speed give indications of how the processing of optical flow modulates locomotor activity.     

Pragmatic expectations and linguistic evidence: Listeners anticipate but do not integrate common ground

When listeners search for the referent of a speaker’s expression, they experience interference from privileged knowledge, knowledge outside of their ‘common ground’ with the speaker. Evidence is presented that this interference reflects limitations in lexical processing. In three experiments, listeners’ eye movements were monitored as they searched for the target of a speaker’s referring expression in a display that also contained a phonological competitor (e.g., bucket/buckle). Listeners anticipated that the speaker would refer to something in common ground, but they did not experience less interference from a competitor in privileged ground than from a matched competitor in common ground. In contrast, interference from the competitor was eliminated when it was ruled out by a semantic constraint. These findings support a view of comprehension as relying on multiple systems with distinct access to information and present a challenge for constraint-based views of common ground.     

肺多发结节与混合磨玻璃结节的应对策略解析

肺结节随访中患者面临的诸多困惑, 如对肺结节认识不足易引起患者陷入心理恐慌, 甚至焦虑、抑郁。患者及一线医生面对肺多发结节和混合密度磨玻璃结节的临床决策时更易出现偏差, 故旨在对肺多发结节和混合密度磨玻璃结节的特点及其临床决策思路进行解析, 其精准的诊断、干预时机的把握及远期疗效的考虑尤为重要,期望对临床一线工作人员及此类患者有所帮助。倡导重视医患共同决策在肺结节诊治中发挥重要作用。

     

Self-Healing Forces and Concepts of Health and Disease. A Historical Discourse

The phenomenon of self-healing forces has again and again challenged doctors in the different historical periods of medical science. They relied on effects of self-healing forces in diagnosis and therapy. They also tried to explain these effects based on the current model of organism. The understanding of this phenomenon has always influenced the understanding of therapy and played a role in defining the concept of health and disease. In the 17th and 18th century the idea of self-healing force was interpreted as a phenomenon related to the organic forces, whereas in the 19th century the explanation was reduced to a materialistic mechanism. Nowadays the knowledge of heath-shock-proteins open the way of a new understanding of the organic defense mechanisms. This revised version was published online in August 2006 with corrections to the Cover Date.     

Internal Forces During Static Prehension: Effects of Age and Grasp Configuration

The authors studied effects of healthy aging on 3 components of the internal force vector during static prehensile tasks. Young and older subjects held an instrumented handle using a 5-digit prismatic grasp under different digit configurations and external torques. Across digit configurations, older subjects showed larger internal normal (grip) and tangential (load-resisting) digit force components and larger internal moment of force. In contrast to earlier reports, safety margin values were not higher in the older subjects. The results show that the increased grip force in older persons is a specific example of a more general age-related problem reflected in the generation of large internal force vectors in prehensile tasks. It is possible that the higher internal forces increase the apparent stiffness of the hand+handle system and, hence, contribute to its stability. This strategy, however, may be maladaptive, energetically wasteful, and inefficient in ensuring safety of hand-held objects.