Sequential muscle activity and its functional role in the upper extremity and trunk during overarm throwing

The proximal-to-distal segmental sequence has been identified in many sports activities, including baseball pitching and ball kicking. However, proximal-to-distal sequential muscle activity has not been identified. The aims of this study were to establish whether sequential muscle activity does occur and, if it does, to determine its functional role. We recorded surface electromyograms (EMGs) for 17 muscles from the upper extremity and abdomen during overarm throwing and detected the onset and peak times as indices of muscle activity. The following electromyographic properties were commonly identified in the participants. First, sequential muscle activity was observed from the scapular protractors to the shoulder horizontal flexors and from the shoulder horizontal flexors to the elbow extensor, but not from the elbow extensor to the wrist flexor or forearm pronator. Secondly, the external oblique contralateral to the throwing arm became activated before the ipsilateral external oblique. This sequence is considered to be very effective for the generation of high force and energy in the trunk. Thirdly, the ipsilateral external oblique began its activity almost at foot strike. Finally, the main activity of the rectus abdominis appeared just before the point of release.     

Information--movement coupling: implications for the organization of research and practice during acquisition of self-paced extrinsic timing skills

Information--movement coupling is a fundamental concept, integral to theorizing on the coordination of goal-directed activity in ecological psychology. In this paper, we examine the implications of this concept for the design of experimental research and the organization of practice during the acquisition of movement coordination in sport tasks. The task vehicle for our analysis is interceptive actions, in particular self-paced extrinsic timing tasks exemplified by serving in sports such as volleyball. Recent research highlighting the relevance of information--movement coupling for the process of practice in sport is discussed. We conclude that information--movement coupling represents an important principle for the structural organization of research and practice in self-paced extrinsic timing tasks and that further work is required to verify its significance across a range of sport movements.     

关于乒乓球选材标准的教练员观点调查

本研究的目的是基于乒乓球教练员对人体形态测量、身体素质能力、生理心理素质、心理以及体型因素的基础上,决定选材的原则和标准。这个研究的反馈者包括40名国际水平的乒乓球教练员(26位来自伊朗,14位来自其它国家),他们是随机抽取的,55%的反馈者持有国际教练员资格学位,教练生涯的平均年数是15.74年。大约有50%的认为7～8岁是选材的最合适年龄段;27.5%认为是5～6岁;17.5%认为是9～10岁。根据分析,发现66.5%选择观察方法;48.1%选择科学方法作为选材时优先考虑的方法。总的来说,34.2%认为教育部门对于选材具有最主要的责任。进一步而言,涉及…     

信息在被谁偷窥——偷窥时代已经到来

我们已经在不知不觉之中被Spyware(间谍软件)所包围，它们悄无声息的偷窥我们在网络上的一举一动，它们将我们的银行账号、企业用户的ID号码和密码传送给第三方。在我们还在为病毒、蠕虫、黑客所困扰的时候，Spyware(间谍软件)却早已在我们电脑安营扎寨。     

麦糟饵钓草鱼

主料：麦芽，是酿制啤酒的主要原料，可去啤酒厂买。酒糟：是酒厂的下脚料．最好是曲酒糟。辅料：米糠或麦麸。以上原料备齐后，将麦芽磨成粉，酒糟搓成散状，将两者各半掺和，加点水打湿，如太黏了可多加些糠或麦麸。用此饵装炸弹钩，钓草鱼效果不错。麦糟饵钓草鱼@李正宇!浙江大荆     

Effect of postsecondary education on the economic status of persons who are deaf or hard of hearing

This article examines the effect that postsecondary education has on earnings and the duration of time spent in the Social Security disability programs for young persons who are deaf or hard of hearing. Our hypothesis is that investments in postsecondary training increase the likelihood of employment for persons who are deaf or hard of hearing and thus reduce dependency on disability-related income support programs. A longitudinal data set based upon records from the National Technical Institute for the Deaf and Social Security administrative records is used for this analysis. We find that those who graduate, even those who graduate with vocational degrees, experience significant earnings benefits and reductions in the duration of time spent on federal disability programs when compared with those who do not graduate with a degree. This finding suggests that reductions in the duration of time spent on Social Security programs are not limited to those with the highest level of scholastic aptitude and that investments in post-secondary education can benefit a broad group of deaf and hard-of-hearing persons. In addition, the data show that individuals who attend college, but withdraw before graduation, fair no better economically than individuals who never attended college.     

Commentary: the coalition for improving maternity services:

A consumer advocate, two childbirth educators, and a certified nurse-midwife each provide commentary on the effectiveness of and potential uses for the Evidence Basis for the Ten Steps of Mother-Friendly Care.