The role of cohabitation in family formation: The United States in comparative perspective

The prevalence of nonmarital cohabitation is steadily increasing in the United States. In evaluating the contribution of this new living arrangement to family formation, analysts have relied primarily on comparisons between individuals who cohabit and those who do not. We complement this line of inquiry by comparing the United States and 16 industrialized nations. We first identify six conceptually distinct ideal types of cohabitation with respect to family formation. We then propose empirical indicators to distinguish between the different ideal types, and estimate the values of these indicators for each of the 17 nations. Our findings indicate that although a number of countries fit an empirical pattern corresponding to one ideal type, cohabitation in the United States is more difficult to characterize.     

The Single Assessment Process in Primary Care: Older People's Accounts of the Process

Recent government policies have been active in addressing socialinclusion and active participation of older people in many aspectsof societal life. Independence and well-being animate thesedevelopments and are evident in the emphasis on person-centredservices within the single assessment process for older people(Department of Health, 2002b). Drawing on a feasibility study of the Single Assessment Processas a ‘case-finding’ approach, this paper presentsfindings drawn from older people’s accounts of this experience.These accounts indicate the potential of the process for identifying‘low-level’ need, whilst raising issues of accessto formal services and resource constraint; also they underlinethe importance of understanding how older people seek ways ofmanaging their own health and well-being, whilst continuingto contribute to the social cohesion of society by providingsupport to their peers and to younger generations. Interdependence, it is suggested, rather than dependence shouldunderlie any approach to assessing older people’s needs,if we are to appreciate and build upon the complexity of olderpeople’s strategies for actively managing their lives.     

不同不育系所配杂交水稻组合在单、双株寄栽条件下的秧苗素质分析

通过对不同不育系所配杂交水稻组合在单、双株寄裁条件下的秧苗素质研究，结果表明：Ⅱ-32A所配组合的总根数、白根数、白根率和分蘖性能等指标均较优，特别是白根率高，根系活力和分案能力强，但繁茂性稍差。冈46A所配组合其突出特点是叶面积和苗高占优势，繁茂性好，秧田各时期的于物质积累能力较强，但根系活力稍差，白根率较低。二汕A所配组合的特点是在发根力和根系活力上稍占优势，白报率较高。D汕A所配组合无突出特点。寄款方式对秧苗素质影响很大，主要表现在前期和后期的差异大。前期双株秧稍占优势，但在后期刊单株放的优势很明显。因此，在土壤肥沃，水源充足的地方，为培育壮秧，增加秧龄弹性，应提倡单株寄栽。     

一类自反代数的单元和自同构

讨论了Ｂａｎａｃｈ空间Ｘ中自反代数　的一些性质。指出了在　中非零单元与一秩算子是等价的．特别证明了　的每一自同构都是自动连续的，此外，若Ｘ还是自反的，则　的自同构必是空间的。     

自由电子激光放大实验的准光腔毫米波信号注入器

本文提出了一种用旋转柱形三反射镜准光腔作为自由电子激光放大实验系统的毫米波信号能量注入器主体的注入装置。理论和实验研究表明,该注入器具有模式单一、注入效率高(49.3％)、单向传输性好(定向传输)和有良好的单色性等一系列显著的优点。     

Kinship Strategies and Self-Sufficiency Among Single Mothers by Choice: Post Modern Family Ties

This article discusses findings from an on-going study of 50 single mothers by choice: women aged 21 to 50 when they become mothers, who are self-supporting economically, and who have chosen to become mothers as unmarried women. The interviews include women (both heterosexual and lesbian) who vary widely by race and social class. We argue that this group of women demonstrate ways of maintaining economic self-sufficiency—relying neither on the state nor on a male provider—through creative efforts at networking, resource sharing, and non-economic exchanges. We find that the route the women take to motherhood (adoption, known donor pregnancies, anonymous donor insemination, or accidental pregnancy) has a strong impact on the makeup of specific kin relationships between the mothers, their children, and others; yet all the mothers strategically forge or foster close ties which enable them to raise their children independently.     

Parenting stress and behavior among single mothers of preschoolers: The mediating role of self‐efficacy

Abstract

This study examines the role of perceived self‐efficacy in mediating relations between mothers’ parenting behavior and variables such as maternal employment status, depressive symptoms, parenting stress, and child behavior problems. Subjects were 93 employed and 95 nonemployed, single, black mothers of a 3–5‐year‐old child who were current and former welfare recipients. Using linear structural relations modeling (LISREL), the findings support a model whereby (a) the more behavior problems the child is perceived to have, the more depressive symptoms the mother feels; (b) the more depressive symptoms the mother feels, the more likely she is to rate herself high in parenting stress; (c) the more depressive symptoms and parenting stress the mother experiences, the lower is the mother's estimate of her self‐efficacy; and (d) the lower the mother's self‐efficacy, the less competent is her parenting. The findings for employment status are similar; i.e., maternal employment predicted a trajectory leading to somewhat better parenting. In addition, child behavior problems were associated with less competent parenting both directly and indirectly through their effect on parenting stress and self‐efficacy. These results suggest that self‐efficacy has import as a mediator of the relations between maternal parenting and other psychosocial variables. There is no evidence, based on these findings, that employment in the low‐wage market is harmful either for single black mothers or their preschool children. However, job availability and an increase in the minimum wage are important policy considerations.     

Correlates of Women's Adjustment During the Separation and Divorce Process

This study sought to clarify those factors related to successful adjustment at different times during the divorce process. A longitudinal research design was used to study three diverse sam- ples of women in the process of adaptation. Certain variables previ- ously found to predict adjustment, such as the woman's a e and the f presence of children, were not significantly associated wit the mul- tiple indicators of adjustment used in this study. Sex role attitudes, social isolation, and inter-spouse acrimony emerged as stronger cor- relates of adjustment. The predictive power of several variables changed over time, emphasizing the importance of controlling the length of separation for a given sample.     

一种改进的单相电路谐波和无功电流检测法

针对牵引供电系统三相/单相供电特性，提出了一种检测谐波的新方法，该方法克服了现存单相系统谐波电流检测法计算复杂、运算量大的缺点，能够实现任意次谐波的单独分析；在LabVIEW平台上易于实现，可用于实际工程问题。经过仿真及实验分析结果表明，该算法能够有效地对任意次谐波进行检测，并能准确显示谐波相位。     

Moments of order statistics from a non-overlapping mixture model with applications to truncated laplace distribution

We employ two different approaches to derive single and product moments of order statistics from a truncated Laplace distribution. A direct evaluation method establishes recurrence relations whereas the more general non-overlapping mixture model incorporates the truncated Laplace distribution as a special case. The results are thereafter applied to estimate location and scale parameters of such distributions.