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941.
電是什么?     
在大自然中,電以形形色色的姿態出現。其中最顯著、最普遍的,就是閃電。鄰近北極地帶(如蘇聯的北方)的居民很熟悉這些雄偉的現象:有時候,在夜間的天空上出現了紅、紫、黄、綠各種顏色的寬闊的、明亮的帶子。它們形成火燄般的帷幕,它們離奇地捲起而又展開。這是“北極光”,它的產生就是由於電。在高山上,當空氣相當乾燥的時候,可以看到“電光”。它們表現爲在金屬物體的尖端上的小小的火燄。古  相似文献   
942.
943.
美国西点陆军学校一向以培养最优秀的领导人才为己任。西点自1802年创校以来,建立了一套独特的教学体系,为国家社会栽培最杰出的领导人才。西点的独特之处是"教给人品德。"一个有品德的领导人,具有一般领导人物所应具有的特质、  相似文献   
944.
1939年夏天,爱因斯坦到位于纽约东部的长岛度假.而我的祖父--大卫·罗斯曼,在那里经营着罗斯曼百货公司.6月的一天,爱因斯坦走进店里.尽管祖父一眼就认出了他,但还是把他当作一名普通顾客对待.  相似文献   
945.
德国的大学和科学   总被引:3,自引:1,他引:3  
你们已经听说我是一个数学家。我的兴趣一直集中于科学本身,而不是它的科学机构和科学组织。不过,今晚我要谈的主要内容是关于德国的大学和科学研究机构,所以我恳求诸位理解我不是谈论这一主题的专家。我是通过我  相似文献   
946.
947.
The genetic and environmental overlap between static and dynamic measures of preschool phonological awareness (PA) and their relation to preschool letter knowledge (LK) and kindergarten reading were examined using monozygotic and dizygotic twin children (maximum N = 1,988). The static tests were those typically used to assess a child's current level of PA such as blending and elision, and the dynamic test included instruction in phoneme identity to assess the child's ability to respond to this instruction. Both forms were influenced by genes and by shared and nonshared environment. The static and dynamic versions were influenced by the same genes, and part of the total genetic influence was shared with LK. They were subject to both overlapping and independent shared environment influences, with the component in common also affecting LK. Nonshared environment influences were mostly independent. Scores from dynamic assessment added only minimally to variance explained in kindergarten reading after LK and static assessment had been factored in. Although one of the genetic factors that influenced both forms of PA also affected kindergarten reading, it was only the one shared with LK. The authors conclude that dynamic assessment of PA in preschool offers little advantage over the more commonly used static forms, especially if LK scores are available, although they acknowledge its potential in cases of preschool educational disadvantage.  相似文献   
948.
949.

Objectives

There is much evidence showing that childhood adversities have considerable effects on the mental and physical health of adults. It could be assumed therefore, that the disease burden of childhood adversities is high. It has not yet been examined, however, whether this is true.

Method

We used data of a large representative sample (N = 7,076) of the general population in the Netherlands. We calculated the disability weight (DW) for each respondent. The DW is a weight factor that reflects the severity of a disease or condition on a scale from 0 (perfect health) to 1 (equivalent to death). We used an algorithm based on the SF-6D to estimate DW. Because the DW indicates the proportion of a healthy life year that is reduced by the specific health state of the individual, it also possible to calculate the total number of years lost due to disability (YLD) in the population. We calculated the years lived with disability (YLD) for 9 different childhood adversities (in the areas of parental psychopathology; abuse and neglect; major life events), as well as for major categories of mental disorders and general medical disorders.

Results

All 9 adversities resulted in a significantly increased DW, except death of a parent before the age of 16. Adversities in the category of abuse and neglect are associated with the highest DWs (0.057), followed by parental psychopathology (0.031) and life events during childhood (0.012). All adversities (46.4% of the population reports one or more adversity) are associated with 20.7 YLD/1,000, which is more than all mental disorders together (12.9 YLD/1,000). The category of abuse/neglect has the highest YLD/1,000 (15.8), which is also higher than all mental disorders together. Adjustment for the presence of mental and general medical disorders resulted in comparable outcomes.

Conclusions

Childhood adversities are more important from a public health point of view than all common mental disorders together, and should be a priority for public health interventions.  相似文献   
950.
To maximize benefits to children and their families, effective practices need to be used competently in child welfare settings. Since the 1990s, researchers and policy makers have focused attention on empirically supported interventions (ESIs). Much less attention has been paid to what is needed to implement these in a range of real-world settings. Without proper implementation, which includes an evaluation strategy from feasibility to fidelity to on-going work on moderators and mediators of program effects, established effective programs can be rendered ineffective in practical application. The paper will touch on progress, to date, of implementation science, its application to child welfare programs and practices, and will highlight a set of practical strategies for implementing empirically supported interventions in child welfare.  相似文献   
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