The developmental consequence of different patterns of maltreatment

From a longitudinal study of 267 high risk families, four different patterns of maltreatment were identified. The mothers have been tested, interviewed and observed in a number of situations starting during the last trimester of pregnancy and continuing at regularly scheduled intervals through the preschool period. The four maltreatment groups were: physical abuse; hostile/verbally abusive; psychologically unavailable; and neglecting. A control group of mothers who provided adequate care was selected from the remaining high risk sample. In an earlier follow-up, among the maltreated children a disproportionately large number of infants were found to be anxiously attached to their mothers at 12 and 18 months, and their performance in a problem-solving situation at age two was poor. In the current follow-up, the children were videotaped at 42 months in a "barrier box" and teaching situation, and at 56 months they were observed in a preschool situation. The physically abused children were distractible, lacked persistence, ego control and enthusiasm, and experienced considerable negative emotion. The children whose mothers were psychologically unavailable showed marked increases in maladaptive patterns of functioning from infancy through preschool. As expected, they were avoidant of their mother, angry, noncompliant, and they were highly dependent. The neglected children had the most difficulty pulling themselves together to deal with various tasks. They lacked self-esteem and agency necessary to cope with their environment.     

Structuring academic conflicts between majority and minority students: Hindrance or help to integration

The effects of two types of structured academic conflict, controversy and debate, were compared with individual study in a study on desegregation. Seventy-two sixth grade students were assigned to conditions on a stratified random basis controlling for sex, reading ability, and ethnic membership. In all three conditions students studied a controversial issue with materials representing both pro and con views. In the controversy condition each learning group was divided into two pairs representing the pro and con sides. In the debate condition each member of a learning group was assigned a pro or con position to represent in a debate with the other three members. In the individualistic condition subjects were told to learn the material without interacting with other students and each student was given all the pro and con materials. The results indicate that controversy promotes the most cross-ethnic verbal rehearsal and exchange of the assigned material, the most concern that all students master the assigned material, the most active search for more information about the topic being studied, the most reevaluation of one's position and incorporation of opponents' arguments, the most liking for the subject matter and the instructional experience, the highest self-esteem, and the most accepting and supportive relationships among minority and majority students. The debate condition generated higher levels of these dependent variables than did individualistic study.     

茯苓抗诱变效应的实验研究

采用姊妹染色单体交换(SCE)和骨髓嗜多染红细胞微核(MN)方法对中药茯苓进行抗诱变细胞学实验研究.评价了茯苓对诱变剂苯并[a]芘(B[a]P)诱发小鼠遗传损伤的拮抗作用.实验表明,茯苓的抗诱变效应是明显的(P<0.01).对SCE的抑止率为37.4%,MN的抑止率为46.7%.本文还对其拮抗机制进行了阐述.提出了茯苓多糖的防护意义.     

The effect of cooperative and individualistic learning experiences on positive and negative cross-handicap relationships

The effects of cooperative and individualistic learning contingencies on interpersonal attraction, social acceptability, and self-esteem between handicapped and nonhandicapped fourth-grade students were tracked and compared. Sixty-nine students were assigned to conditions on a stratified random basis controlling for handicap, sex, and age. They participated in the study for 45 min a day for 54 instructional days during science class. Nonhandicapped peer ratings of the social acceptability of each handicapped student and several attitude measures were obtained four separate times at 18-day intervals. The results indicate that continued use of cooperative learning contingencies promote positive growth in interpersonal attraction, social acceptability, and self-esteem between handicapped and nonhandicapped students. The results also indicate that when cooperative learning contingencies are replaced with individualized learning contingencies, decay in the above-mentioned variables occurs.     

基于移动IP切换技术的研究

本文介绍了移动IP的基本概念和IP的切换问题,分析了影响切换时通信性能的3个因素:移动检测、重新注册以及与上层协议的相互作用,提出了新的切换方案:将链路标识嵌入到FA的代理广播消息中,使得MN可以据此进行快速的移动检测;MN为发送端时,切换后主动发送未应答的TCP包;MN为接收端时,切换后通过主动发送多个TCP SACK包来请求发送端发送已丢失的TCP包。     

Intercultural education for multicultural societies: Critical issues

This article presents evidence for the need for intercultural education in multicultural societies. Pupils who are culturally different from the majority need it to learn to function effectively in their own culture as well as in the majority culture. Since an important objective of education is to prepare individuals to function effectively in their environment, all children in multicultural societies could profit from exposure to effective intercultural education. Our research with American teachers and their Latin American or Hispanic pupils suggests that teachers also need to learn about the patterns of perceptions, values, and behaviors of culturally different pupils. Objections to intercultural education are listed and refuted. Advantages and disadvantages of three new approaches to intercultural education are discussed. Special attention is given to the attributional approach, an informational approach which is particularly well suited for use in educational settings. Research bearing on the effectiveness of this approach is presented.     

无铅锡膏的评价与选择

基于无铅锡膏基本参数的分析,介绍经典锡膏评估验证法、Indium公司的4步无铅焊膏评估法和实际测试评估法3种锡膏评价体系.通过对每种评估法的系统性和实际操作性的分析,总结出企业生产中最有效的锡膏选择法,并给出了一个实例.