The cycle of violence

Despite widespread belief that violence begets violence, methodological problems substantially restrict knowledge of the long-term consequences of childhood victimization. Empirical evidence for this cycle of violence has been examined. Findings from a cohort study show that being abused or neglected as a child increases one's risk for delinquency, adult criminal behavior, and violent criminal behavior. However, the majority of abused and neglected children do not become delinquent, criminal, or violent. Caveats in interpreting these findings and their implications are discussed in this article.     

Role of genotype in the cycle of violence in maltreated children

We studied a large sample of male children from birth to adulthood to determine why some children who are maltreated grow up to develop antisocial behavior, whereas others do not. A functional polymorphism in the gene encoding the neurotransmitter-metabolizing enzyme monoamine oxidase A (MAOA) was found to moderate the effect of maltreatment. Maltreated children with a genotype conferring high levels of MAOA expression were less likely to develop antisocial problems. These findings may partly explain why not all victims of maltreatment grow up to victimize others, and they provide epidemiological evidence that genotypes can moderate children's sensitivity to environmental insults.     

The violence of the lambs

Researchers are increasingly coming to view violence as the end result of multiple risk factors that may include a biological vulnerability that can be brought out or reinforced by social environment. Longitudinal studies are demonstrating that children who become chronically violent adults generally are difficult from early childhood. But just which early risk factors are most powerful, and how they interact, is proving very tough to sort out.     

对《李尔》中暴力主题的分析及其教育意义

《李尔》是英国剧作家爱德华.邦德以莎士比亚的剧作《李尔王》为素材创作的寓言剧。邦德曾说：＂这（暴力）是一个难以解决的社会问题——它将关乎人类的生死存亡。＂因此,他的大多数作品都是与暴力相关的。通过对《李尔》一剧进行分析从而揭露出暴力的本质——道义与自由的光环下掩盖的血腥。在此基础上,对其所蕴含的教育意义作了初步探讨。     

家庭暴力问题思考

近年来,日益突出的家庭暴力问题,加剧了婚姻的动荡,危害了社会的安定。应充分认识这一问题的危害性,并找出其产生的根源,采取相应对策加以制止。     

生态系统反馈形成原因的分析

早已注意到生态系统中普遍存在着正、负反馈现象,然而却很少研究这两类反馈形成的原因.作者认为正反馈主要起因于现状是未来发展的主要基础,生命对于外界条件有主动的选择性,即有选择地吸收它熟悉的物质和信息,体现着经济高效的生存对策.正反馈的另外成因来自于生物成员间加大的原始协作、性状突变以及锻炼和学习.负反馈的主要成因是共同资源限制、相互干扰抑制、大量因子的自身维持代价变大以及冗余变大.文中以较大篇幅讨论现状是未来发展的主要基础和大量因子自身维持代价变大的问题.     

Dysfunction in the neural circuitry of emotion regulation--a possible prelude to violence

Emotion is normally regulated in the human brain by a complex circuit consisting of the orbital frontal cortex, amygdala, anterior cingulate cortex, and several other interconnected regions. There are both genetic and environmental contributions to the structure and function of this circuitry. We posit that impulsive aggression and violence arise as a consequence of faulty emotion regulation. Indeed, the prefrontal cortex receives a major serotonergic projection, which is dysfunctional in individuals who show impulsive violence. Individuals vulnerable to faulty regulation of negative emotion are at risk for violence and aggression. Research on the neural circuitry of emotion regulation suggests new avenues of intervention for such at-risk populations.     

Disruption of the nitrogen cycle in acidified lakes

Experimental acidification of two small soft-water lakes caused nitrification to cease at pH values of 5.4 to 5.7. The resulting blockage of the nitrogen cycle caused a progressive accumulation of amnonium. When the epermental acidification of one of the lakes was ended and the pH was raised to 5.4, nitrification resumed after a time lag of 1 year.     

农业产业化运行机制的现实分析

农业产业化是一项涉及多部门、多产业、多主体的系统工程，这一系统能否高效的运作.是实施农业产业化发展战略的关键。木文通过对农业产业化运行模式和运行机制的现实分析.阐述了在新形势下如何有效建立起农业产业化的运行机制。     

大学生校园暴力问题的心理诱因

由于社会的发展变化及不良生活方式与价值观对大学生的侵蚀,如今大学校园内的暴力行为对校园和社会构成了很大威胁,已逐渐成为一个全球高度关注的社会问题。大学校园暴力看似一种个别的、简单的社会现象,其实具有复杂的社会心理背景。要解决这个问题,必须家庭、学校、社会等方面的共同配合。大学生的暴力问题与自身的年龄、身心发育特征有着密切的关联。为有效遏制和预防大学生暴力行为和暴力犯罪,必须分析其根源,以便从源头上防治。     

Mechanisms of Herbicide-resistance

The first case of herbicide-resistance was record- ed that a biotype of common groundsel (Senecio vul- garis L.) resistant to s- triazines, atrazine and simaz- ine, isolated from a conifer field in Washington State where simazine was repeatedly used for m…     

植物耐旱性及其机理

本文综合评述了植物的各种耐旱机理。依据植物对干旱胁迫的反应行为,把植物的耐旱机理分为3个基本类型:(1)逃避干旱;(2)高水势延迟脱水耐旱;(3)低水势忍耐脱水耐旱。逃避干旱的植物(如沙漠短生植物)具有在严重的干旱胁迫发生之前就完成其生命周期的能力,但它们的特点本文未加以讨论。而着重讨论了忍耐干旱的植物的耐旱特点。高水势延迟脱水的植物是以保持水分吸收和减少水分丧失为其主要的耐旱特征。而低水势忍耐脱水的植物则是以保持膨压和原生质忍耐脱水为其主要特征。