Trajectory of quality of mother-child interactions: Prospective links with child socioemotional functioning

Research shows that the quality of mother-child interactions is a robust antecedent of child socioemotional functioning. Yet, relatively little is known about the evolution of this relational quality over time, and even less about how changes in relational quality may bear on child adjustment. This study aimed to describe the trajectory of quality of mother-child interactions between ages 2 and 7 and to investigate associations between individual differences in this trajectory and child socioemotional functioning at age 8. In a sample of 233 mother-child dyads primarily comprised of White French-Canadian mothers, the quality of interactions was assessed during 10-min play sequences when children were aged 2, 4, and 7 years. Child internalizing, externalizing, and prosocial behaviors were reported by a subsample of 171 teachers at age 8. The results showed that on average, quality of mother-child interactions decreased over time. In terms of individual differences, children who experienced a slower decrease in the quality of interactions with their mother from 2 to 7 years showed less internalizing behavior at age 8, over and above initial quality at 2 years. Children involved in higher quality interactions with their mother at 2 years showed more prosocial and less externalizing behavior at age 8, independent of the subsequent decrease in the quality of those interactions. The findings suggest that initial levels and subsequent changes in the quality of mother-child interactions are two distinct indicators of their relationship with potentially different implications for child adjustment.     

Life here beyond now: Chronotopes of the ideal life among Iranian transnationals

I address how U.S.‐based Iranian transnationals’ migration paths affect their (re)‐construction of chronotopes of the ideal life. Adopting an ethnographically grounded, discourse‐analytic approach, I illustrate how participants with student visas and U.S. Green Cards position themselves differently relative to images of success here [in the U.S.] and lack of success there [in Iran]. I argue that the chronotopes of success here and lack of success there (re)‐constructed by non‐resident Iranian students are prompted by a large‐scale cultural chronotope which pertains to their aspiration to stay in the U.S. This chronotope of ‘life beyond’ is less about a ‘remove from homeland’ and more about an ideal future in the host country. Migrants’ desires and anxieties, I argue, can determine what receives topical prominence in migration chronotopes – as in the case of Iranian educational migrants whose future positionings make temporality topically more prominent than spatiality.

     

一种新型并联机床的最优轨迹规划

提出了一种新型并联机床的最优轨迹规划方法,其过程是在参数空间进行轨迹规划,再将参数空间的运动轨迹映射到关节空间。在轨迹规划中,以雅可比矩阵条件数的倒数作为适应度函数,利用遗传算法优化了并联机床的多余自由度。仿真计算结果表明:最优轨迹规划方法既能给出并联机床加工过程中的灵巧构型,又可使得并联机床获得平稳的运动性能。     

A multivariate finite mixture latent trajectory model with application to dementia studies

Dementia patients exhibit considerable heterogeneity in individual trajectories of cognitive decline, with some patients showing rapid decline following diagnoses while others exhibiting slower decline or remaining stable for several years. Dementia studies often collect longitudinal measures of multiple neuropsychological tests aimed to measure patients’ decline across a number of cognitive domains. We propose a multivariate finite mixture latent trajectory model to identify distinct longitudinal patterns of cognitive decline simultaneously in multiple cognitive domains, each of which is measured by multiple neuropsychological tests. EM algorithm is used for parameter estimation and posterior probabilities are used to predict latent class membership. We present results of a simulation study demonstrating adequate performance of our proposed approach and apply our model to the Uniform Data Set from the National Alzheimer's Coordinating Center to identify cognitive decline patterns among dementia patients.     

Placement type matters: Placement experiences in relation to justice system involvement among child welfare-involved youth and young adults

Out-of-home placement in the child welfare system is related to justice system involvement. Yet, few studies address the similarities and differences of child welfare placement types in relation to justice system involvement within the same sample of youth, which can provide a more nuanced understanding of the relationship between the two. Utilizing a sample of child welfare youth with substantial out-of-home placements (N = 794), we investigate trajectory group experiences on each of three child welfare placement types, and cross-tabulate each with justice system trajectory groups to examine subgroups. The five-group model fits best for foster homes and group homes; four groups for residential facilities. Relationships between justice system groups and placement types were significant. Youth with chronic justice system involvement had more experiences in group homes and residential facilities; youth with less justice system contact tended to have foster home experiences. Implications for policy and practice are presented.     

Developmental Trajectories of Head Start Children's Reading and Home Environment Scores: Across Ethnicities

ABSTRACT

To investigate the relationship of ethnicity in the development of children in Head Start, this study examined the associations between ethnicities and reading trajectories and whether trajectories of home environment could over time explain their differential associations. Participants (N = 696) were selected from the National Longitudinal Survey of Youth data. Results indicated some similarities and differences in the results obtained. Study findings suggest including an environmentally sensitive family component in Head Start and suggest an early enrollment policy targeting at-risk populations to maintain long-term Head Start impacts across ethnicities. Future research and follow-up studies should investigate other family components that positively affect long-term development among Black, Hispanic, and White children participating in the Head Start program.     

建筑节能技术轨道的探索

鉴于建筑节能技术在缓解能源短缺和实现可持续发展的重要作用,引入技术经济学前沿思想的技术轨道理论,首先提出了建筑节能技术轨道的概念。其次,针对行业特征,建立了建筑节能技术轨道的约束体系、分类体系和核心体系：约束体系包括技术约束、经济约束和社会环境约束;分类体系包括建筑构造系统节能技术轨道、建筑设备系统节能技术轨道、能源供给系统节能技术轨道和运行管理系统节能技术轨道;核心体系包括建筑节能技术的发展轨迹、形成轨道、可能轨道、最优轨道、延伸轨道和转辙轨道。最后,着重分析了建筑节能技术轨道的宏观研究和微观研究的特点。     

A Latent Growth Curve Model of Nonmarital Births,Abortions, and Pregnancies: Did Welfare Reform Play a Role in Changing the Trajectories?

This article uses latent growth models to examine the effect of three welfare reform policies, viz., family caps, stricter work requirements, and time limits on fertility outcomes. The study is the first to extend the application of this statistical modeling approach to an examination of reproductive behavior. Using state level panel data for 1992–2005 we attempt to determine if welfare reform has contributed to changes in the trajectories of nonmarital births, abortions, and pregnancies beyond what would have naturally occurred through the passage of time. Our results show that states vary considerably in both their mean initial level as well as linear trajectories of fertility outcomes and that welfare reform has helped hasten the decline in nonmarital births, abortions, and pregnancies.     

西藏非公有制经济跨越式发展的战略构想

改革开放以来,特别是“十五大”以来,西藏个体、私营等非公有制经济飞速发展壮大,已经成为国民经济的重要组成部分和促进社会生产力发展的重要力量。非公有制经济已成为西藏国民经济中最具活力的新的经济增长点、成为西藏增加社会资本和财政收入的重要来源,同时为西藏地区创造就业机会、增加人民收入、稳定社会局势等方面作出了重要贡献。但是,在新的环境、新的发展阶段,西藏非公有制经济与发达省份相比,在所有制结构上还存在一定的差距。因此,应进一步积极鼓励和支持个体、私营等非公有制经济发展,优化经济结构。     

复杂技术系统背景下技术体制新解

在解释技术体制、技术范式和技术轨迹间的关系,并指出原有技术体制在复杂技术系统下存在的缺陷的基础上,引入技术场网络作为技术体制的新维度,解释复杂技术系统中技术场网络主体间的技术联系,并区分了这种技术联系的强弱,讨论了技术体制的新维度与原有维度间的关系,提出了相应的假设。