Impaired acuity of the approximate number system underlies mathematical learning disability (dyscalculia)

Many children have significant mathematical learning disabilities (MLD, or dyscalculia) despite adequate schooling. The current study hypothesizes that MLD partly results from a deficiency in the Approximate Number System (ANS) that supports nonverbal numerical representations across species and throughout development. In this study of 71 ninth graders, it is shown that students with MLD have significantly poorer ANS precision than students in all other mathematics achievement groups (low, typically, and high achieving), as measured by psychophysical assessments of ANS acuity (w) and of the mappings between ANS representations and number words (cv). This relation persists even when controlling for domain-general abilities. Furthermore, this ANS precision does not differentiate low-achieving from typically achieving students, suggesting an ANS deficit that is specific to MLD.     

传统制造业集群协同演进机制探析——天津自行车集群纵向案例研究

产业集群对区域乃至国家经济发展具有重要的作用,然而产业集群发展过程中的影响因素及其相互作用机制至今仍未得到系统的阐述.从协同演进理论视角,结合组织生态学、制度理论、战略管理理论和社会网络理论等,对天津自行车产业集群的发展历程展开多层次、时间序列的分析,以深入挖掘产业集群发展过程中各种要素的相互作用、协同演进机制,提出产业集群的发展是企业战略、产业环境以及制度环境协同演进的过程,同时集群发展过程中创业者的社会资本发挥重要作用.这种将多维理论视角相结合起来进行分析的方法,有利于更好地理解产业集群的演进机制.     

Examining the influence of the parent-initiated and coach-created motivational climates upon athletes' perfectionistic cognitions

The aims of this study are threefold. First, we investigate the influence of the parent-initiated motivational climate upon elite junior athletes' perfectionistic cognitions. Second, we examine whether the coach-created motivational climate predicts additional variance in elite junior athletes' perfectionistic cognitions beyond the effects associated with the parent-initiated motivational climate. Third, we test the moderating role of athletes' gender and age in the relationship between the parent-initiated and coach-created motivational climates and athletes' perfectionistic cognitions. A total of 190 elite junior athletes (mean age 15.2 years, s?=?1.5, range 10-18) completed the Parent-Initiated Motivational Climate Questionnaire-2 (White & Duda, 1993), the Perceived Motivational Climate in Sport Questionnaire-2 (Newton, Duda, & Yin, 2000), and the Perfectionistic Cognitions Inventory (Flett, Hewitt, Blankstein, & Gray, 1998). Regression analyses revealed that mother- and father-initiated worry-conducive climates, the father-initiated success-without-effort climate, and the coach-created performance motivational climate predicted male athletes' perfectionistic cognitions. Female athletes' perfectionistic cognitions were predicted by the mother-initiated worry-conducive climate, father-initiated learning-enjoyment climate, and both dimensions of the coach-created climate. Finally, athletes' gender emerged as a significant moderator of the mother-initiated worry-conducive climate and athletes' perfectionistic cognitions relationship. Findings confirm that the parent-initiated motivational climate is a significant predictor of athletes' perfectionism-related thoughts, and provide initial support for the influence of the coach-created motivation climate over children's perfectionistic cognitions.     

Benzodiazepine administration prevents the use of error-correction mechanisms during fear extinction

Three experiments examined the effect of systemic administration of the benzodiazepine midazolam on extinction and re-extinction of conditioned fear. Experiment 1 demonstrated that midazolam administration prior to extinction of a conditioned stimulus (CS) impaired that extinction when rats were subsequently tested drug free; however, extinction was spared if rats were extinguished, reconditioned, and re-extinguished under midazolam. Experiment 2 provided a replication of this effect within-subjects; rats were conditioned to two CSs (A and B), extinguished to one (A-), reconditioned to both, and then extinguished/re-extinguished to both stimuli in compound (AB-), under either vehicle or midazolam. On the drug-free test, rats given midazolam froze more to the CS that had been extinguished (B) than the one that been re-extinguished (A). The final experiment examined whether extinction under midazolam was regulated by prediction error. Rats were trained with three CSs (A, B, C) and extinguished to two (A-, C-). These stimuli then underwent additional extinction under midazolam or vehicle, with one CS now presented in compound with the non-extinguished CS (AB-, C-). Rats were then tested for fear of A relative to C. Rats given vehicle showed a deepening of extinction to A relative to C, as is predicted from error-correction models; however, rats given midazolam failed to show any such discrepancy in responding. The results are interpreted to indicate that the drug reduced prediction error during extinction by reducing fear, and rats were able to re-extinguish fear via a retrieval mechanism that is independent of prediction error.     

The Right to Teach, the Right to Learn

Believe that the findings and recommendations of the Elton Committee have much to offer schools for children with emotional and behavioural difficulties, as well as mainstream schools. They outline the way they have introduced 'assertive discipline' into behaviour management policy of the school.     

Reliability of No Child Left Behind Accountability Designs

The No Child Left Behind Act of 2001 requires states to establish accountability systems that are both valid and reliable. If one follows the language of the law literally, there is no design that will meet both requirements. If one interprets the law more flexibly, it is possible to create such a design. States will need to approach the problem carefully if they are going to appropriately balance the various probabilities of making incorrect decisions about schools.     

The development of education for medical librarians

Formal education for medical library specialization was initiated only thirty-two years ago despite the fact that medical libraries received special treatment for many years before that time. The philosophy of specialized education was developed as early as 1925, and this theory was finally put into practice beginning with the medical reference and bibliography course given at Columbia in 1939. In the late 1940s the requisites for medical librarians were formalized into a certification code by the Medical Library Association, and since that time specialized education for medical librarians has grown stronger using this code as a guideline. This education consists basically of two types-formal library school courses and internship programs which offer a working-while-learning situation. Now that the established programs have a few years of history, there is a need for evaluation and restatement of goals and methods.