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221.
农村初中生学习适应性发展的研究   总被引:27,自引:0,他引:27  
本研究运用测量的方法考察了 3 86名农村初中生学习适应性的发展。结果表明 ,初一学生的学习适应性显著地好于初二、初三、初四的学生 ;男女学生的学习适应性差异显著 ;在“学习态度”、“学习技术”、“学习环境”、“身心健康”四个分测验中 ,年级差异非常显著 ;优等生和差生在学习适应性上也存在着非常显著的差异。  相似文献   
222.
在生理水平的血管壁切应力属于优性因子,能促进血管重建,抑制内皮细胞凋亡,调节内皮细胞分泌功能,使内皮细胞形态产生适应性变化;而显著升高或降低的血管壁切应力则属于非优因子,导致高血压恶性循环发生、促进动脉粥样硬化及动脉血栓形成。实现切应力非优向优转化的重要途径是降低高血压和选择性阻断切应力对基因表达的调节  相似文献   
223.
Humans exhibit a remarkable ability to discriminate variations in object volume based on natural haptic perception. The discrimination thresholds for the haptic volume perception of the whole hand are well known, but the discrimination thresholds for haptic volume perception of fingers and phalanges are still unknown. In the present study, two psychophysical experiments were performed to investigate haptic volume perception in various fingers and phalanges. The configurations of both experiments were completely dependent on haptic volume perception from the fingers and phalanges. The participants were asked to blindly discriminate the volume variation of regular solid objects in a random order by using the distal phalanx, medial phalanx, and proximal phalanx of their index finger, middle finger, ring finger, and little finger. The discrimination threshold of haptic volume perception gradually decreases from the little finger to the index finger as well as from the proximal phalanx to the distal phalanx. Overall, both the shape of the target and the part of the finger in contact with the target significantly influence the precision of haptic perception of volume. This substantial data set provides detailed and compelling perspectives on the haptic system, including for discrimination of the spatial size of objects and for performing more general perceptual processes.  相似文献   
224.
孝的本义是“善事父母”。因为人为父母所生养而成长 ,应该给以回报 ,所以孔孟主张对父母尽孝。先秦儒家还提出父慈子孝的对等关系 ,在道德人格上是平等的。秦汉大一统以后 ,移孝作忠 ,伦理向政治伸延 ,君父对臣子形成统治与被统治的关系。汉朝称以孝治天下 ,建立察孝廉、奖孝悌的制度。对孝道的提倡 ,用以造就一批父慈子孝、兄友弟恭的孝悌家庭 ,对以家族为本位、家国同构的中国古代 ,儿女尽孝能和睦家庭 ,进而安定社会 ,增强中华民族凝聚力 ,有一定的正面作用。同时把孝亲与忠君联系起来 ,所谓忠臣出于孝子之门 ,对于维护汉皇朝的统治亦有安定的作用。但是历朝的孝治政策亦有负面效应。由于朝廷奖励孝子 ,有的人就弄虚作假 ,败坏社会风气 ,把孝道作为沽名钓誉的工具。有的虽然真心尽孝 ,但措施不当 ,形成愚昧行为。正面与负面就形成中国古代孝文化的两重性。  相似文献   
225.
结核病诊治进展与科技革命   总被引:2,自引:0,他引:2  
现代科技革命极大地促进了结核病各方面的发展.微生物学和免疫学的发展,揭示了结核病的病因、发病机制、病理生理的本质,分子生物学技术使结核病的基础研究不仅停留在器官、细胞水平,而是深入到蛋白质、核酸、基因的水平;基因治疗的方法可望从根本上治疗结核病.高新技术的产物如X线照片、电子计算机断层扫描、纤维支气管镜检查和新药的出现等极大地提高了临床诊治的能力.借助于各种先进的医疗设备而进行精确的诊断,基因治疗将成为一种崭新的治疗手段.  相似文献   
226.
It was recently demonstrated that detecting target objects (e.g., animals) in natural scenes can be done in a dual-task paradigm, in the near absence of spatial attention. Under the same conditions, subjects were unable to perform apparently simpler tasks involving synthetic stimuli (e.g., discriminating randomly rotated Ts and Ls, or a bisected colour disc and its mirror image). Classical theories predict that attention is more critical for the recognition of complex stimuli that cannot be easily separated on a single feature dimension. Therefore, these puzzling results have raised a number of questions. If it is not the complexity of a stimulus, what then determines the recognition task's attentional requirements? How does this differ between natural and artificial stimuli? What can these observations tell us about the mechanism of natural scene processing as well as its relation to attention? Here we show that removing colour information, or doubling the amount of information to be analysed, failed to make the natural scene categorization tasks significantly more “attention demanding”. Conversely, increasing discriminability or predictability did not diminish the need for attention in the case of synthetic stimuli. However, when the familiar letters, such as Ts or Ls, were presented upright, full attention was no longer required for discrimination. This suggests that familiarity and meaningfulness might be among the factors that determine attentional requirements for both natural and synthetic stimuli.  相似文献   
227.
ABSTRACT

This study investigated the association between exercise type and inhibition of prepotent responses and error detection. Totally, 75 adults (M = 68.88 years) were classified into one of three exercise groups: those who were regular participants in open- or closed-skill forms of exercise, and those who exercised only irregularly. The participants completed a Stroop and task-switching tasks with event-related brain potentials (ERPs) recorded. The results revealed that regular exercisers displayed faster reaction times (RTs) in the Stroop task compared with irregular exercisers. The open-skill exercisers exhibited smaller N200 and larger P300a amplitudes in the Stroop task compared with irregular exercisers. Furthermore, the open-skill exercisers showed a tendency of shorter error-related negativity latencies at the task-witching test. The findings suggest that older adults may gain extra cognitive benefits in areas such as inhibition functioning and error processing from participating in open-skill forms of physical exercises.  相似文献   
228.
ABSTRACT

Using faces as the priming stimuli, the present study explored the influence of facial expressions on the activation of gender stereotypes using a lexical decision paradigm. Experiment 1 explored the activation of gender stereotypes when the facial primes contained only gender information. The results showed that gender stereotypes were activated. In Experiment 2, the facial primes contained both gender category and expression information. The results indicated that gender stereotypes were not activated. Experiment 3 required the participants to make emotion, gender, or impression decisions concerning the facial primes before the lexical decision task. The results showed that gender stereotypes were not activated in emotion and impression decisions conditions, whereas stereotypes were activated in gender decisions condition. These finding suggest that facial expressions can inhibit automatic activation of gender stereotypes, unless the perceivers perform gender categorization processing to prime faces intentionally.  相似文献   
229.
A process is described for the fabrication of opal-like thin films by controlling a solid–liquid interface moving at an inclined glass substrate. A special airflow is adopted to control solvent evaporation. SEM images and photographs show that the films, composed of polystyrene spheres, are coloured, flat, uniform, packed multilayers, and are well arrayed over a large scale. The ordered domains range in size from 10 to 15?µm. The spheres in suspension crystallized, caused by an intense interaction between the spheres on the boundary between the suspension and the substrate. A wide photonic band gap is observed in the normal-incidence transmission spectra of the films fabricated by this method. Cracks and defects in the films are examined and discussed.  相似文献   
230.
Molecular dynamics simulations of nanoscale multilayered Cu/Ag metals have been conducted under uniaxial tensile straining to elucidate the out-of-plane deformation behaviour relevant to tensile spallation experiments. In nanolayers with pristine architectures, plastic dissipation prior to crack nucleation is suppressed owing to the high hydrostatic tensile stress state. The presence of sources for micro-twinning partials, such as micro-cracks or columnar grain boundaries, result in abundant deformation twin lamellae across multiple Cu/Ag interlayers. Plastic recovery is observed during unloading of the nanolayers.  相似文献   
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