8,857 research outputs found
Socioeconomic disadvantage in childhood as a predictor of excessive gestational weight gain and obesity in midlife adulthood.
BackgroundLower childhood socioeconomic position is associated with greater risk of adult obesity among women, but not men. Pregnancy-related weight changes may contribute to this gender difference. The objectives of this study were to determine the associations between: 1. childhood socioeconomic disadvantage and midlife obesity; 2. excessive gestational weight gain (GWG) and midlife obesity; and 3. childhood socioeconomic disadvantage and excessive GWG, among a representative sample of childbearing women.MethodsWe constructed marginal structural models for seven measures of childhood socioeconomic position for 4780 parous women in the United States, using National Longitudinal Survey of Youth (1979-2010) data. Institute of Medicine definitions were used for excessive GWG; body mass index ≥30 at age 40 defined midlife obesity. Analyses were separated by race/ethnicity. Additionally, we estimated controlled direct effects of childhood socioeconomic disadvantage on midlife obesity under a condition of never gaining excessively in pregnancy.ResultsLow parental education, but not other measures of childhood disadvantage, was associated with greater midlife obesity among non-black non-Hispanic women. Among black and Hispanic mothers, childhood socioeconomic disadvantage was not consistently associated with midlife obesity. Excessive GWG was associated with greater midlife obesity in all racial/ethnic groups. Childhood socioeconomic disadvantage was not statistically significantly associated with excessive GWG in any group. Controlled direct effects were not consistently weaker than total effects.ConclusionsChildhood socioeconomic disadvantage was associated with adult obesity, but not with excessive gestational weight gain, and only for certain disadvantage measures among non-black non-Hispanic mothers. Prevention of excessive GWG may benefit all groups through reducing obesity, but excessive GWG does not appear to serve as a mediator between childhood socioeconomic position and adult obesity in women
The Human Thioesterase II Protein Binds to a Site on HIV-1 Nef Critical for CD4 Down-regulation
A HIV-1 Nef affinity column was used to purify a 35-kDa Nef-interacting protein from T-cell lysates. The 35-kDa protein was identified by peptide microsequence analysis as the human thioesterase II (hTE) enzyme, an enzyme previously identified in a yeast two-hybrid screen as a potential Nef-interacting protein. Immunofluorescence studies showed that hTE localizes to peroxisomes and that coexpression of Nef and hTE leads to relocalization of Nef to peroxisomes. Interaction of Nef and hTE was abolished by point mutations in Nef at residues Asp108, Leu112, Phe121, Pro122, and Asp123. All of these mutations also abrogated the ability of Nef to down-regulate CD4 from the surface of HIV-infected cells. Based on the x-ray and NMR structures of Nef, these residues define a surface on Nef critical for CD4 down-regulation. A subset of these mutations also affected the ability of Nef to down-regulate major histocompatibility complex class I. These results, taken together with previous studies, identify a region on Nef critical for most of its known functions. However, not all Nef alleles bind to hTE with high affinity, so the role of hTE during HIV infection remains uncertain
Diagnostics Of Disks Around Hot Stars
We discuss three different observational diagnostics related to disks around hot stars: absorption line determinations of rotational velocities of Be stars; polarization diagnostics of circumstellar disks; and X-ray line diagnostics of one specific magnetized hot star, theta(1) Ori C. Some common themes that emerge from these studies include (a) the benefits of having a specific physical model as a framework for interpreting diagnostic data; (b) the importance of combining several different types of observational diagnostics of the same objects; and (c) that while there is often the need to reinterpret traditional diagnostics in light of new theoretical advances, there are many new and powerful diagnostics that are, or will soon be, available for the study of disks around hot stars
Instructional Policy and Classroom Performance: The Mathematics Reform in California
Educational reformers increasingly seek to manipulate policies regarding assessment, curriculum, and professional development in order to improve instruction. They assume that manipulating these elements of instructional policy will change teachers\u27 practice, which will then improve student performance. We formalize these ideas into a rudimentary model of the relations among instructional policy, teaching, and learning. We propose that successful instructional policies are themselves instructional in nature: because teachers figure as a key connection between policy and practice, their opportunities to learn about and from policy are a crucial influence both on their practice, and, at least indirectly, on student achievement. Using data from a 1994 survey of California elementary school teachers and 1994 student California Learning Assessment System (CLAS) scores, we examine the influence of assessment, curriculum, and professional development on teacher practice and student achievement. Our results bear out the usefulness of the model: under circumstances that we identify, policy can affect practice, and both can affect student performance
Instruction, Capacity, and Improvement
Since World War II, efforts to improve schools have numbered in the thousands. Most efforts have concentrated on improving the curriculum materials used in schools or on training teachers in new instructional methods. Many of these efforts have gone under the banner of building instructional capacity, a term that for decades has been featured prominently in conversations about educational reform. Unfortunately, three decades of research has found that only a few interventions have had detectable effects on instruction and that, when such effects are detected, they rarely are sustained over time. A review of research and professional experience with school improvement suggests several explanations for these disheartening findings. One is that schools are complex social organizations situated within, and vitally affected by, other complex social systems including families, communities, and professional and regulatory agencies. The larger social environment of schools constrains and shapes the actions of teachers, students, and administrators, often in ways that greatly complicate the work of school improvement. Challenges to school improvement are particularly acute in highpoverty settings where recruiting wellqualified teachers is difficult and where the emotional and health problems of students often deflects attention to educational issues or impedes work on them. As a result, many researchers now believe that school improvement involves much more than efforts to change interactions occurring within schools. To succeed, school improvement interventions also must attend to the complex relationships that exist among intervention agents, schools, and their social environments
State Policy and Classroom Performance: Mathematics Reform in California
In the early 1990\u27s many states tried to devise more robust and coherent instructional policies, in efforts to make teaching and learning more thoughtful and demanding. Policymakers and reformers pressed teachers to help students understand mathematical concepts, to interpret serious literature, to write creatively about their own ideas and experiences, and to converse thoughtfully about history and social science. But these efforts to reform instruction encountered skepticism about the link between policy and pedagogy. Skeptics ask if it is reasonable to expect state policies to steer teaching and learning sharply away from long-established conventional practice, noting that previous efforts to change practice on a large scale had failed.
As instructional policy moved to the top of many state education agendas in the late 1990s, interest in the relations between policy and practice has grown. In this issue of CPRE Policy Briefs, we report encouraging findings from an important study that addresses these relationships. We use data from a 1994 survey of California elementary school teachers to probe the classroom effects of state efforts to reform mathematics teaching and learning in California. We report that policy changes did lead both to changed classroom practice and to improved student performance.
In this brief, we develop a rudimentary model of the relationship between policy and practice. Student achievement is the ultimate dependent measure; teachers’ reported classroom practice in mathematics is an influence on achievement, but practice also is a measure of the effects of teachers’ learning opportunities about new math curriculum. We present results which show that teachers’ learning opportunities influenced their practice, and that both teachers’ learning opportunities and their practice influenced students’ mathematics achievement. The results suggest that teachers’ practice can change in ways that favorably influence student achievement, and that policy can play an important role in making those changes possible.
We begin with a review of the California reform, briefly describe the research approach, and then discuss the major findings
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