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911.
学校必须传授给学生们以符合现代科学进展、符合辩证唯物主义世界观和共产主义道德等客观实际的深刻而长期有用的知识,并且必须进行劳动教育,培养劳动习惯和爱劳动的情感。实现这一目的的途径之一就是改进普通中学的课程和教科书。在已公布的课程标准(即教学大纲)的章、节、课题的说明中预先指出了学生务必学到的要点,同时按照学校集体能力的实际情况,确定补充的或次要的内容。这一关于课程的改进是为了减轻学生的过重负担,同时也指明了所有学生可以掌握的并且必定能达到较高水平的一定量的基本教材的内容。  相似文献   
912.
本文报道澳门蝗虫24种,对其分布和区系作了简要分析。  相似文献   
913.
时间的价值     
时间的价值就像金钱的价值一样:完全体现在如何使用上。只肯花一点点钱以维持生命的守财奴其实等于是个穷光蛋,他的万贯家财也就形同乌有。同样,舍不得花费时间去获取更多的幸福、去使更多的人幸福的人,也是虚度年华。  相似文献   
914.
Lee AC  Ou Y  Fong D 《Child abuse & neglect》2003,27(11):1323-1329
OBJECTIVE: To describe a pattern of abusive head injury in a series of children older than 4 years of age. METHODS: A hospital chart review of abused children with skull fractures from 1999 to 2001 was carried out. The clinical features, social background, and subsequent outcome and management are described. RESULTS: An 11-year-old girl and a pair of brothers of ages 7 and 9 were identified. The girl was attacked with a hammer during sleep by her stepmother, who committed suicide shortly afterwards. After craniotomy and intensive care, the child survived her multiple depressed fractures, intracranial bleeding, and brain contusion. Two brothers from a second family were attacked from behind with a hammer by their biological father, who was subsequently found to have undiagnosed schizophrenia. A depressed occipital fracture, without intracranial injury, was found in each child. The elder brother also had metacarpal fractures. Both children recovered without surgical intervention. CONCLUSION: A pattern of abusive head injury was described in older children with depressed skull fractures from blunt injury. The abusing parents were seriously mentally disturbed, and the abusive acts closely resembled child homicide.  相似文献   
915.
Referees in German first-league soccer games do not award as many yellow cards in the beginning of a game as should be statistically expected. One explanation for this effect is the concept of game management (Mascarenhas, Collins, & Mortimer, 2002). Alternatively, the consistency model (Haubensak, 1992) explains the effect as a necessity of the judgment situation: Referees need to calibrate a judgment scale, and, to preserve degrees of freedom in that scale, they need to avoid extreme category judgments in the beginning (i.e., yellow cards). Experiment 1 shows that referees who judge scenes in the context of a game award fewer yellow cards than referees who see the same scenes in random order. Experiment 2 shows the combined influence of game management (by explicitly providing information about the game situation) and calibration (early vs. late scenes in the time course of a game). Theoretical implications for expert refereeing and referee training are discussed.  相似文献   
916.
Removal of aqueous phenol compound by vacuum membrane distillation   总被引:4,自引:0,他引:4  
1.IntroductionPhenolisanimportantchemicalindustrymaterial,butitalsoaboundswithserioushazardtoenvironmentandthreatstohumanhealth.Rigidruleshavebeenmadeoutonthephenoldischargeconcentration.Researchesonthetreatmentofphenolwastewaterwerecarriedoutinvariouscountries[1-5].Membraneseparationmethodsincludingreverseosmosis,ultrafiltrationandpervaporationhaveattractedmuchattentionforphenolwastewatertreatment,withcelluloseacetate(CA)membraneemployedmostly[6].Membranedistillationisanewmembraneseparation…  相似文献   
917.
918.
我国课堂教学评价研究概况、问题与设想   总被引:4,自引:0,他引:4  
概述我国课堂教学评价研究的现状,包括对课堂教学本质和价值取向、评价标准和指标、教学评价方法的研究。分析我国课堂教学评价存在的问题,包括局限于理论构建,缺少课堂实证研究;缺乏对课堂教学客观、准确、精细的描述;局限于评价标准与指标法,缺乏有效方法的综合运用。提出今后研究的设想,包括进行课堂教学的实证研究,提供对课堂教学的多角度、多类型的描述,同时建立教学评价标准指标体系和行为分类系统,综合使用定量方法和质的方法。  相似文献   
919.
本期推出两篇短小精美的文章,表达了父爱的温馨,有兴趣的读者朋友不妨将它们作为范文来诵渎。  相似文献   
920.
Objective: To study the regulation of blood pulse volume via photoplethysmography (PPG) signal detected from toe, while the lower limb is passively raised in different height positions. Methods: Use a modified non-invasive PPG technique to detect the blood pulse signal on toe with infrared (IR) photo sensor. A protocol consisting of two postures, i.e., supine and 45° reclining, was designed to conduct laboratory trial in this study. During the period of performing the protocol of these postures, the lower limb was passively raised from the heights of 10 cm to 60 cm randomly and individually with sponge blocks underneath the foot. Results: In the supine posture, the higher the foot was passively raised, the more the blood PPG signal decreased. In the 45° reclining posture, the blood PPG signal increased at the beginning and then decreased in the foot height position from 10 cm to 60 cm. In both postures the normalized AC signal changes significantly while the normalized DC signal changes little. Conclusion: The toe PPG signals can obviously indicate the regulated blood volume change with the designated postural procedures due to the heart level position.  相似文献   
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