Maternal work hours and adolescents’ School outcomes among low-income families in four urban counties

We examine how changes in maternal work hours affect adolescent children's school participation and performance outcomes using data from interviews in 1998 and 2001 with approximately 1700 women who, in May 1995, were welfare-reliant, single mothers of adolescents living in neighborhoods of concentrated poverty in Cuyahoga (Cleveland), Los Angeles, Miami-Dade, and Philadelphia counties. Analyses control for a broad array of mothers' characteristics, including their psychological and physical health, experiences with domestic violence and substance abuse, as well as unobserved time-invariant characteristics. In fixed-effects models, we find unfavorable effects of increased maternal work hours on three of six outcomes: skipping school, performing above average, and parental contact about behavior problems. Adolescent-aged sons seem to be particularly sensitive to changes in mothers' hours of work.     

氯化钙-氨吸附式制冷的实验研究

介绍了以氯化钙一氨为工质对的吸附式两床循环制冷装置，并在此实验装置上进行了实验研究，得出了以氯化钙一氨为工质对的连续循环制冷系统的制冷量、性能系数COP随时间的变化关系．结果表明，此装置的制冷效果优于设计指标，设计的壳管式吸附器具有实用性．     

Exploring the experiences and dynamics of an unconditional cash transfer for low-income mothers: A mixed-methods study

ABSTRACT

Little is understood about how an unconditional cash transfer might operate and affect behavior among low-income parents of infants in the United States. We investigate these questions using data from a random-assignment pilot study (N?=?30) in which unconditional cash transfers were distributed monthly on debit cards to two groups of low-income parents in New York City during the first 12 months of their newborns’ lives. Mothers were randomized to receive either $100 per month or $20 per month. Mothers distinguished spending the cash transfer on essentials vs. extras, such as going out to dinner with family. The monthly cash transfer “tided them over,” even at the lower amount of $20, especially when income from other sources ran short at the end of the month. Some mothers reported saving money for unexpected expenses.     

构建社会主义和谐社会符合穆斯林的宗教信仰和根本利益

和谐是人类普遍的追求,是历史发展的永恒主题。实现社会和谐,建设美好社会,是世界上各民族、各宗教孜孜以求的共同社会理想。现在党和国家提出构建社会主义和谐社会,那么中国穆斯林这样一个信仰伊斯兰教的中华民族的组成群体如何在构建和谐社会的过程中发挥自己的作用,作出应有的贡献?本文以宗教和社会主义相适应,各民族携手共建和谐社会这个角度,从对和谐社会的理解和认识、伊斯兰教的和谐观、中国穆斯林应该为构建社会主义和谐社会这一共同目标而不懈努力三个方面探讨了伊斯兰教和穆斯林群众对构建社会主义和谐社会应有的认识、态度及实践。     

山西省生猪产品竞争力比较分析

养猪业是农村经济的重要组成部分,是畜牧业的主导。山西省地处黄土高原,有发展养猪业的资源优势。运用简单比较法,对山西省生猪产品在不同的饲养方式下与全国生猪产品在同种饲养方式下进行对比分析,揭示了山西省生猪产品生产在成本、价格、收益方面与全国同指标(平均)水平对比的优(劣)势状况,畜产品质量安全状况,并提出提升山西省生猪产品竞争力的对策建议。     

On Block Ordering of Variables in Graphical Modelling

Abstract.  In graphical modelling, the existence of substantive background knowledge on block ordering of variables is used to perform structural learning within the family of chain graphs (CGs) in which every block corresponds to an undirected graph and edges joining vertices in different blocks are directed in accordance with the ordering. We show that this practice may lead to an inappropriate restriction of the search space and introduce the concept of labelled block ordering B corresponding to a family of B - consistent CGs in which every block may be either an undirected graph or a directed acyclic graph or, more generally, a CG. In this way we provide a flexible tool for specifying subsets of chain graphs, and we observe that the most relevant subsets of CGs considered in the literature are families of B -consistent CGs for the appropriate choice of B . Structural learning within a family of B -consistent CGs requires to deal with Markov equivalence. We provide a graphical characterization of equivalence classes of B -consistent CGs, namely the B - essential graphs , as well as a procedure to construct the B -essential graph for any given equivalence class of B -consistent chain graphs. Both largest CGs and essential graphs turn out to be special cases of B -essential graphs.     

论柏拉图“理念”论及其对中世纪基督教神学之影响

在柏拉图思想体系中,“理念”论是其核心,它充分彰显了古希腊人追问永恒、绝对之终极本体的渴求,尤其是其“两重世界”的划分和“善”的理念之绝对先验性和超越性以及“回忆说”表现出的一种神学倾向,与中世纪基督教思想一拍即合,为基督教中彼岸世界与上帝之“合理”存在和“光照论”提供了思想根基。在一定意义上说,柏拉图的“理念”论为中世纪基督教神学的产生提供了理论的核心。     

How an earnings supplement can affect union formation among low-income single mothers

Using data from an experimental evaluation in two Canadian provinces, we found that offering an earnings supplement to single mothers in place of welfare altered rates of marriage and cohabitation, but that the direction of the effects varied by province. Our findings suggest that research on the relationship between women's economic well-being and marital decisions at the national level is likely to mask important variation at the local level. After eliminating several explanations for the opposite effects in the two provinces, we propose that local labor markets and local policy contexts are potentially important mediating characteristics of marriage and cohabitation.     

Paternal child care and children's development

This paper uses the NLSY-Child data to assess the effects on cognitive and social-emotional development of father care as a child care arrangement among children in two-parent families with working mothers. Our results show that father care for infants is no better or worse than other types of arrangements. However, toddlers in non-paternal modes of child care (e.g., relatives, family day care or center care) have slightly better cognitive outcomes than those whose fathers provided care. Although our analyses do not provide a definitive explanation for this finding, there is a substantial influx of fathers in our data who provide child care in years 2 and 3 and these fathers appear compositionally different from fathers who provided care during a child's infancy. In particular, there is some indication that these fathers who are newly providing care during a child's toddler years may be temporary care providers due to changing economic circumstances. The research was supported by NICHD grant #HD30944. Responsible editor: Deborah Cobb-Clark.