哈尔滨东部农业区土壤重金属污染研究

为了解哈尔滨市东部农业区土壤环境质量,促进农产品生产向高产优质方向发展,采用火焰原子吸收光谱法和BCR提取法对各土壤样本的重金属元素Cu、Zn、Pb、Ni、Cd和Cr的含量和形态进行测定,并测定了土壤的理化性质.采用潜在生态风险评价方法,以松嫩平原背景值作为参比值,对该市东部农业土壤重金属的潜在生态危害作出评价.结果表明,该市东部农业土壤已受到污染,累积污染程度具有Zn＞ Cd＞Cu＞Cr＞Pb＞Ni的特征;土壤重金属的形态分布中,残渣态占据其总含量的绝大部分,Cd、Pb、Zn有效态含量较高.潜在生态危害指数法结果表明:Cd是农业土壤中潜在生态危害最严重的元素,达到中等生态危害程度,Cu、Pb、Zn、Ni和Cr均为轻微生态危害程度,总体上处于低等生态危害水平.相关性分析表明,重金属元素污染来源比较广泛,受多方面因素影响.     

对中国教育技术学科发展的再思考:方法、实践与理论

本文基于对方法、实践、理论这三个关乎我国教育技术学科发展的核心问题的思考,提出了三个主要观点:(1)以科学实证的方法指导研究,特别是发展"基于证据的研究";(2)以技术设计的思想指导教学实践和装备发展,同时促进"研究与设计的互动"以及"技术与文化的互动",并由此构建促进不断进步的学与教理论以及催生新的学习文化和教育实践的重要动力系统;(3)自信规范地构建理论体系,梳理多层面的已有理论积累,并在未来的学科发展中更多地增强专业组织的凝聚与导向作用.     

影响排球比赛发球的因素及调整对策

从心理学角度入手,分析研究运动员在排球比赛中临场的心理状态、自我调节及心理训练方法,对其提出正确的心理定位和建议对策。     

Adolescents’ Friendships,Academic Achievement,and Risk Behaviors: Same-Behavior and Cross-Behavior Selection and Influence Processes

This study examined to what extent adolescents’ and their friends’ risk behaviors (i.e., delinquency and alcohol use) hinder or promote their academic achievement (grade point average [GPA]), and vice versa. Longitudinal data were used (N = 1,219 seventh- to ninth-grade adolescents; M_age = 13.69). Results showed that risk behaviors negatively affected adolescents’ GPA, whereas GPA protected against engaging in risk behaviors. Moreover, adolescents tended to select friends who have similar behaviors and friends’ behaviors became more similar over time (same-behavior selection and influence). Furthermore, although same-behavior effects seemed to dominate, evidence was found for some cross-behavior selection effects and a tendency in seventh grade for cross-behavior influence effects. Concluding, it is important to investigate the interplay between different behaviors with longitudinal social network analysis.     

Marital Conflict Predicts Mother-to-Infant Adrenocortical Transmission

Employing an experimental design, mother-to-infant transmission of stress was examined. Mothers (N = 117) were randomized to either have a positive or conflictual discussion with their marital partners, after which infants (age = 6 months) participated in a fear and frustration task. Saliva samples were collected to assess maternal cortisol responses to the discussion and infant cortisol responses to the challenge task. Results indicate maternal cortisol reactivity and recovery to the conflict (but not positive) discussion predicted infant cortisol reactivity to the infant challenge. Mothers’ positive affect during the discussion buffered, and intrusion during the free-play potentiated, mother-to-infant adrenocortical transmission. These findings advance our understanding of the social and contextual regulation of adrenocortical activity in early childhood.     

The Role of Desegregation and Teachers of Color in Discipline Disproportionality

The Urban Review - Scholars note the multitude of ways that the continual shifts in the racial composition of schools affect students, but fewer studies consider the implications of such shifts for...     

大学生课外科技创新活动体系构建的探索与实践

结合国外高校成功经验,阐述了如何构建大学生课外科技创新活动体系,为学生提供科技创新的学习实践平台,使其将所学理论知识进行实践综合与创造,培养其创新意识和创新精神,促进创新型工程人才的培养。     

以企业主导的校企合作大学本科毕业设计培养模式

为改变传统的单一模式对学生的束缚,加强产学研合作,提高学生毕业设计的主动性,更好地培养动手和实践能力强的高级应用型专业人才以满足现代社会的需求。探讨指导本科毕业设计（论文）多元化的新途径,试行＂以企业为主导的校企合作指导本科毕业设计（论文）培养模式＂,以期突破现今指导本科毕业设计（论文）的固定模式,以更好地培养学生的能动性,同时也为学生了解企业和为今后就业创造机会。     

Pathways to Parental Engagement: Contributions of Parents,Teachers, and Schools in Cultural Context

Research Findings: This study examined correlates of parents’ reported school engagement in an ethnically diverse, rural sample (N = 346) of parents and teachers in kindergarten through Grade 2. Of particular interest were role expectations and family–school relationships in American Indian families, who historically have been marginalized by schools. In terms of role expectations, parents and teachers agreed that they should support each other’s roles, parents should have more responsibility than schools for teaching social skills, and families and schools should have shared responsibility for children’s academic success. Teachers had higher expectations than parents for parent engagement, which in turn was greater when parent–teacher communication was more frequent and the school climate was more welcoming. American Indian parents more strongly endorsed a separation of family and school roles and felt less welcomed at school; ethnicity moderated correlates of reported parent engagement. Practice or Policy: These findings have practical promise given that parent–teacher communication, school climate, and role expectations are more easily altered than are structural barriers that also may hinder parents’ involvement in supporting their children’s early education.     

Supporting Teaching Faculty as Scholars: A Developmental Model

Professors from across the academic disciplines at Council for Christian College & Universities (CCCU) institutions have traditionally excelled in their teaching. In recent years, CCCU faculty have also increasingly been expected to conduct research and to publish scholarly work. As CCCU institutions expand research and scholarship expectations for faculty, we must also provide the requisite support for professors to be effective in this work. In this article, we highlight institutional practices to encourage, support, and celebrate scholarly writing and research by faculty. Drawing upon findings from Zuidema's 2016 survey of CCCU chief academic officers, we offer benchmark practices for communicating expectations, offering tangible supports and resources, augmenting accountability measures with formative feedback, and recognizing and celebrating scholarship. Against this backdrop, we highlight practical, affordable strategies used at Point Loma Nazarene University (PLNU) in California and Dordt College in Iowa, two CCCU institutions that have increased expectations for scholarship in recent years. Through these illustrations, we aim to inspire new and creative strategies for supporting scholarship by showing how these practices are an outgrowth of a developmental philosophy of leadership that seeks to invest in the core resource of CCCU institutions: the faculty.