Acute effect of stretching modalities on global coordination and kicking accuracy in 12–13 year-old soccer players

The aim of the study was to compare the effect of stretching procedures on global coordination and accuracy in instep soccer kicks achieved in different stress conditions. Twenty male young soccer players completed the global coordination test (GC), the instep kicking accuracy test in free (FKA) and in time-pressure (TPKA) conditions, either after static (SS), dynamic (DS), ballistic (BS) or no-stretching (CTR) protocols, on nonconsecutive days and in a randomized order. After performing a 5 min standardized intensity jogging (70% of MAV), followed by stretching exercises for 10 min, each participant completed, successively, the GC, FKA and TPKA tests. Accuracy data, heart-rate, rating of perceived exertion and task difficulty perception were recorded and analyzed using a two-way ANOVA. GC scores were analyzed using one way ANOVA with repeated measures. The results showed higher GC and TPKA performances after DS and BS procedures. However, there was no effect of the stretching procedures on FKA. The GC scores increased by 10.8% and 7.2% after DS and BS, respectively, but were not affected by SS. Compared to FKA, the TPKA accuracy significantly decreased by 20.2% after CTR (p < 0.01) and 30.7% SS (p < 0.001) with no significant difference after DS (10.1%; p > 0.05) and BS (11.0%; p > 0.05). The use of dynamic and ballistic stretching yielded to better GC scores and helped reducing the adverse effect of time-pressure on instep kicking accuracy. Consequently, dynamic and ballistic exercises can be recommended before practicing activities requiring coordination and lower limbs speed and accuracy.     

Test-potentiated learning of motor sequences

We investigated effects of retrieving body movements from memory on subsequent re-encoding of these movements (i.e., test-potentiated learning). In Experiment 1, participants first learned to perform 12 sequential finger movements as responses to letter stimuli. Eight of these movements then had to be recalled in response to their stimuli (initial test). Subsequently, learning trials were repeated for four of the previously to-be-retrieved movements as well as the previously not-to-be-retrieved movements. Restudy benefited from prior retrieval. In a final test, again requiring motoric recall in response to letter stimuli, performance was better for restudied items that were previously cued for retrieval as compared to items that had been restudied without prior retrieval. However, no such indirect testing benefit occurred when initial and final testing formats were incongruent, that is, when participants had to recall the stimuli in response to movements as cues at the final test. In Experiment 2, we replicated the finding of test-potentiated learning with a different design, manipulating initial-testing status between participants.     

Effects of within-class differences in sample responding on acquired sample equivalence

Two experiments examined whether acquired sample equivalence in many-toone matching was affected by variation in sample-response requirements. In each experiment, pigeons responded on either identical or different response schedules to the sample stimuli that occasioned the same reinforced comparison choice (i.e., to the within-class samples). Transfer-of-control tests were then conducted to determine acquired equivalence, or lack thereof, between these samples. In both experiments, there was minimal or no evidence of acquired sample equivalence when pigeons responded differently to the samples within each common-choice class. By contrast, transfer was observed if pigeons responded (a) identically to all sample stimuli, or (b) identically to samples within each common-choice class (viz., to samples that occasioned the same reinforced choice) and differently to samples from different classes (viz., to samples that occasioned different choices). These results may help to explain the recent lack of evidence for response membership in pigeons' acquired equivalence (Urcuioli, Lionello-DeNolf, Michalek, & Vasconcelos, 2006). They also raise questions about the functional sample stimuli and about possible interactions between acquired equivalence and acquired distinctiveness.     

Development of Phonological Awareness in Bilingual Chinese Children

This study investigated the phonological awareness of 219 first, second, and fourth grade Cantonese-speaking children from the south of China, who received immersion Mandarin instruction beginning in the first grade. Children received onset, rime and tone awareness tasks in Cantonese and Mandarin. Children performed better on the Cantonese onset awareness task in grade one, but the difference disappeared in higher grades. However, their performance on the rime and tone awareness tasks was better in Mandarin. These results reflect the phonological structure of the two languages: Mandarin has a more complex onset system, whereas Cantonese has more complex tone and rime systems. Moreover, children’s phonological awareness increased faster in Mandarin, which likely resulted from Mandarin instruction. Confirmatory factor analysis suggested that onset-rime awareness is a universal construct, whereas tone awareness is a language-specific construct.     

创伤截肢后的假肢康复

5·12汶川地震使当地许多伤员肢体残缺,对伤者的生理和心理产生了重大的影响。帮助这些伤员尽快走出阴影,使他们在灾后能够最大程度的身心康复,重新回归社会,假肢的装配和使用是目前最有效的方法。为了使假肢能够更好地替代残缺肢体的功能,应当从截肢前着手,包括患者截肢平面的选择、残端的正确处理。术后早期对患者进行功能锻炼指导,防止畸形发生,尽可能早地根据患者自身情况选配合适的假肢,并指导患者正确使用和维护假肢,使其能够成功地回归社会,增强截肢者生活的信心。     

辅助生殖技术与女性生殖系统肿瘤的关系及其辩证思考

辅助生殖技术给不孕患者带来了希望,为肿瘤患者保留了生育能力,另一方面也可能导致女性生殖系统肿瘤和一系列伦理学问题。因此,用哲学的观点客观地看待辅助生殖技术与女性生殖系统肿瘤发生风险之间的关系,将有助于临床医生进一步提高辅助生殖技术安全性的认识,选择最佳的促排卵方案。     

论生命健康权在医疗活动中的支配转移

现有法学理论认为,生命健康权是一种具有绝对性和支配性的民事权利,通常不得以任何形式让与他人,即不得买卖、转移、赠与或继承。自然人只能对自己的生命健康权实现有限制的支配。医疗实践证明,生命健康权存在支配转移的实际情况,生命健康权的支配转移是对现有法学理论的补充和完善。     

从假装到心理表征理论:假装认识训练的影响

研究探究假装情境及假装认识对幼儿心理理论(Theory of mind)发展的影响。实验一考察60名3~4岁幼儿在假装情境下的信念认识任务中的表现,发现幼儿对假装的早期认识的出现要早于对信念的认识的出现,假装情境对幼儿的信念认识没有直接促进作用。实验二对42名在信念认识任务上表现不佳的幼儿进行假装认识训练,结果发现假装认识训练促进了幼儿的信念认识,促进效应须经历一段时间才显现。研究支持假装认识在心理理论发展中具有重要作用的假设,但潜在作用机制仍有待进一步探究。     

不同认知风格学生的问题共性意识水平对解题迁移的影响

 本文通过实验,对初中生的平面几何成绩与其认知风格之间的关系、解题者对迁移题与源题之间共性关系的意识水平对解题迁移的影响进行了研究。结果表明:(1)初中生的平面几何成绩与认知风格有显著的正相关;(2)在平面几何解题过程中,当迁移题与源题之间具有结构共同性,且表面相似性和条件隐蔽性为中等程度时,解题者对先后问题之间共性关系的意识水平对解题迁移有显著影响。