WorldWideScience

Sample records for school segregation rate

  1. Income Segregation between Schools and School Districts

    Science.gov (United States)

    Owens, Ann; Reardon, Sean F.; Jencks, Christopher

    2016-01-01

    Although trends in the racial segregation of schools are well documented, less is known about trends in income segregation. We use multiple data sources to document trends in income segregation between schools and school districts. Between-district income segregation of families with children enrolled in public school increased by over 15% from…

  2. School Segregation and Racial Academic Achievement Gaps

    Directory of Open Access Journals (Sweden)

    Sean F. Reardon

    2016-09-01

    Full Text Available Although it is clear that racial segregation is linked to academic achievement gaps, the mechanisms underlying this link have been debated since James Coleman published his eponymous 1966 report. In this paper, I examine sixteen distinct measures of segregation to determine which is most strongly associated with academic achievement gaps. I find clear evidence that one aspect of segregation in particular—the disparity in average school poverty rates between white and black students’ schools—is consistently the single most powerful correlate of achievement gaps, a pattern that holds in both bivariate and multivariate analyses. This implies that high-poverty schools are, on average, much less effective than lower-poverty schools and suggests that strategies that reduce the differential exposure of black, Hispanic, and white students to poor schoolmates may lead to meaningful reductions in academic achievement gaps.

  3. Losing Ground: School Segregation in Massachuestts

    Science.gov (United States)

    Ayscue, Jennifer B.; Greenberg, Alyssa

    2013-01-01

    Though once a leader in school integration, Massachusetts has regressed over the last two decades as its students of color have experienced intensifying school segregation. This report investigates trends in school segregation in Massachusetts by examining concentration, exposure, and evenness measures by both race and class. First, the report…

  4. Income Segregation between Schools and School Districts. CEPA Working Paper No. 16-04

    Science.gov (United States)

    Owens, Ann; Reardon, Sean F.; Jencks, Christopher

    2016-01-01

    Although trends in the racial segregation of schools are well documented, less is known about trends in "income" segregation. We use multiple data sources to document trends in income segregation between schools and school districts. Between-district income segregation of families with children enrolled in public school increased by over…

  5. "Brown" at 62: School Segregation by Race, Poverty and State

    Science.gov (United States)

    Orfield, Gary; Ee, Jongyeon; Frankenberg, Erica; Siegel-Hawley, Genevieve

    2016-01-01

    As the anniversary of "Brown v. Board of Education" decision arrives again without any major initiatives to mitigate spreading and deepening segregation in the nation's schools, the Civil Rights Project adds to a growing national discussion with a research brief drawn from a much broader study of school segregation to be published in…

  6. Gender-Segregated Schooling: A Problem Disguised as a Solution

    Science.gov (United States)

    Fabes, Richard A.; Martin, Carol Lynn; Hanish, Laura D.; Galligan, Kathrine; Pahlke, Erin

    2015-01-01

    Gender-segregated (GS) schooling has become popular in the United States despite the fact that every major review has concluded that GS schooling is not superior to coeducational schooling. Moreover, concern has been raised that GS schooling leads to negative effects, including increased gender stereotyping. We argue that these negative effects…

  7. Standardized Testing and School Segregation: Like Tinder for Fire?

    Science.gov (United States)

    Knoester, Matthew; Au, Wayne

    2017-01-01

    Recent research suggests that high-stakes standardized testing has played a negative role in the segregation of children by race and class in schools. In this article we review research on the overall effects of segregation, the positive and negative aspects of how desegregation plans were carried out following the 1954 Supreme Court decision…

  8. Segregation 2.0: The New Generation of School Segregation in the 21st Century

    Science.gov (United States)

    Thompson Dorsey, Dana N.

    2013-01-01

    Students are more racially segregated in schools today than they were in the late 1960s and prior to the enforcement of court-ordered desegregation in school districts across the country. This special issue addresses the overarching theme of policies, practices, or roles and responsibilities of various stakeholders that may directly or indirectly…

  9. Integrated schools, segregated curriculum: effects of within-school segregation on adolescent health behaviors and educational aspirations.

    Science.gov (United States)

    Walsemann, Katrina M; Bell, Bethany A

    2010-09-01

    We examined the extent to which within-school segregation, as measured by unevenness in the distribution of Black and White adolescents across levels of the English curriculum (advanced placement-international baccalaureate-honors, general, remedial, or no English), was associated with smoking, drinking, and educational aspirations, which previous studies found are related to school racial/ethnic composition. We analyzed data from wave 1 of the National Longitudinal Study of Adolescent Health, restricting our sample to non-Hispanic Blacks (n=2731) and Whites (n=4158) who from 1994 to 1995 attended high schools that enrolled Black and White students. White female students had higher predicted probabilities of smoking or drinking than did Black female students; the largest differences were in schools with high levels of within-school segregation. Black male students had higher predicted probabilities of high educational aspirations than did White male students in schools with low levels of within-school segregation; this association was attenuated for Black males attending schools with moderate or high levels of within-school segregation. Our results provide evidence that within-school segregation may influence both students' aspirations and their behaviors.

  10. Educational Justice, Segregated Schooling and Vocational Education

    Science.gov (United States)

    Giesinger, Johannes

    2017-01-01

    The philosophical debate on educational justice currently focusses on the Anglo-American situation. This essay brings in an additional perspective. It provides a justice-oriented critique of the segregated education systems in German-speaking countries. First, arguments that are commonly put forward in favour of these systems are rejected. Second,…

  11. School Segregation, Charter Schools, and Access to Quality Education*

    Science.gov (United States)

    Logan, John R.; Burdick-Will, Julia

    2015-01-01

    Race, class, neighborhood, and school quality are all highly inter-related in the American educational system. In the last decade a new factor has come into play, the option of attending a charter school. We offer a comprehensive analysis of the disparities among public schools attended by white, black, Hispanic, Asian, and Native American children in 2010–2011, including all districts in which charter schools existed. We compare schools in terms of poverty concentration, racial composition, and standardized test scores, and we also examine how attending a charter or non-charter school affects these differences. Black and Hispanic (and to a lesser extent Native American and Asian) students attend elementary and high schools with higher rates of poverty than white students. Especially for whites and Asians, attending a charter school means lower exposure to poverty. Children’s own race and the poverty and charter status of their schools affect the test scores and racial isolation of schools that children attend in complex combinations. Most intriguing, attending a charter school means attending a better performing school in high-poverty areas but a lower performing school in low-poverty areas. Yet even in the best case the positive effect of attending a charter school only slightly offsets the disadvantages of black and Hispanic students. PMID:27616813

  12. The role of ethnic school segregation for adolescents’ religious salience

    OpenAIRE

    Van der Bracht, Koen; D'hondt, Fanny; Van Houtte, Mieke; Van de Putte, Bart; Stevens, Peter

    2016-01-01

    Public concerns over the possible effects of school segregation on immigrant and ethnic majority religiosity have been on the rise over the last few years. In this paper we focus on (1) the association between ethnic school composition and religious salience, (2) intergenerational differences in religious salience and (3) the role of ethnic school composition for intergenerational differences in religious salience. We perform analyses on religious salience, one five-point Likert scale item me...

  13. Racial Residential Segregation of School-Age Children and Adults: The Role of Schooling as a Segregating Force

    Directory of Open Access Journals (Sweden)

    Ann Owens

    2017-02-01

    Full Text Available Neighborhoods are critical contexts for children’s well-being, but differences in neighborhood inequality among children and adults are understudied. I document racial segregation between neighborhoods among school-age children and adults in 2000 and 2010 and find that though the racial composition of children’s and adults’ neighborhoods is similar, exposure to own-age neighbors varies. Compared with adults’ exposure to other adults, children are exposed to fewer white and more minority, particularly Hispanic, children. This is due in part to compositional differences, but children are also more unevenly sorted across neighborhoods by race than adults. One explanation for higher segregation among children is that parents consider school options when making residential choices. Consistent with this hypothesis, I find that school district boundaries account for a larger proportion of neighborhood segregation among children than among adults. Future research on spatial inequality must consider the multiple contexts differentially contributing to inequality among children and adults.

  14. Segregating Schools: The Foreseeable Consequences of Tuition Tax Credits.

    Science.gov (United States)

    Yale Law Journal, 1979

    1979-01-01

    Argues that the effect of a proposed tuition tax credit is school segregation, creating serious constitutional objections under the due process clause. A voucher system would avoid these constitutional objections. Available from the Yale Law Journal, 401A Yale Station, New Haven, CT 06520. (Author/IRT)

  15. Framing Hostilities: Analysis of Mission Statements from Segregated Chicana/o Schools

    Science.gov (United States)

    Orozco, Richard

    2012-01-01

    This study examined discourses used in mission statements from segregated Chicana/o and White schools. The words and phrases used in segregated Chicana/o school mission statements produce negatively oriented frames that make transparent low expectations and negative attitudes compared to those used in segregated White schools. These frames become…

  16. Freedom from Racial Barriers: The Empirical Evidence on Vouchers and Segregation. School Choice Issues in Depth

    Science.gov (United States)

    Forster, Greg

    2006-01-01

    This report collects the results of all available studies using valid empirical methods to compare segregation in public and private schools, both in general and in the context of school voucher programs. Examining the widespread claims that private schools have high segregation levels and vouchers will lead to greater segregation, this report…

  17. Ending to What End? The Impact of the Termination of Court-Desegregation Orders on Residential Segregation and School Dropout Rates

    Science.gov (United States)

    Liebowitz, David D.

    2018-01-01

    In the early 1990s, the Supreme Court established standards to facilitate the release of school districts from racial desegregation orders. Over the next two decades, federal courts declared almost half of all districts under court order in 1991 to be "unitary"--that is, to have met their obligations to eliminate dual systems of…

  18. School Segregation and Disparities in Urban, Suburban, and Rural Areas

    Science.gov (United States)

    Logan, John R.; Burdick-Will, Julia

    2018-01-01

    Much of the literature on racial and ethnic educational inequality focuses on the contrast between Black and Hispanic students in urban areas and white suburban students. This study extends past research on school segregation and racial/ethnic disparities by highlighting the importance of rural areas and regional variation. Although schools in rural America are disproportionately white, they nevertheless are like urban schools, and disadvantaged relative to suburban schools, in terms of poverty and test performance. The group most affected by rural school disadvantage is Native Americans, who are a small share of students nationally but much more prominent and highly disadvantaged in rural areas, particularly in some parts of the country. These figures suggest a strong case for including rural schools in the continuing conversation about how to deal with unfairness in public education. PMID:29430018

  19. Segregation Levels in Cleveland Public Schools and the Cleveland Voucher Program. School Choice Issues in the State

    Science.gov (United States)

    Forster, Greg

    2006-01-01

    Examining the widespread claims that private schools have high segregation levels and vouchers will lead to greater segregation, this study finds that both assertions are empirically unsupportable. Private schools participating in Cleveland's voucher program are much less segregated than Cleveland's public schools. This means that students using…

  20. Settle for Segregation or Strive for Diversity? A Defining Moment for Maryland's Public Schools

    Science.gov (United States)

    Ayscue, Jennifer B.

    2013-01-01

    Maryland, as one of 17 states that had de jure segregation, has an intense history of school segregation. Following the 1954 Brown decision, school districts across the state employed various methods to desegregate their schools, including mandatory busing in Prince George's County, magnet schools in Montgomery County, and a freedom of choice plan…

  1. School Performance, School Segregation, and Stress-Related Symptoms: Comparing Helsinki and Stockholm

    Science.gov (United States)

    Modin, Bitte; Karvonen, Sakari; Rahkonen, Ossi; Östberg, Viveca

    2015-01-01

    This study investigates cross-cultural differences in the interrelation between school performance, school segregation, and stress-related health among 9th-grade students in the greater Stockholm and Helsinki areas. Contrary to the Swedish case, it has been proposed that school performance in Finland is largely independent of the specific school…

  2. Shopping for Schools or Shopping for Peers: Public Schools and Catchment Area Segregation

    Science.gov (United States)

    Rowe, Emma E.; Lubienski, Christopher

    2017-01-01

    Market theory positions the consumer as a rational choice actor, making informed schooling choices on the basis of "hard" evidence of relative school effectiveness. Yet there are concerns that parents simply choose schools based on socio-demographic characteristics, thus leading to greater social segregation and undercutting the…

  3. On Reconstructing School Segregation: The Efficacy and Equity of Single-Sex Schooling

    Science.gov (United States)

    Billger, Sherrilyn M.

    2009-01-01

    A change to Title IX has spurred new single-sex public schooling in the US. Until recently, nearly all gender-segregated schools were private, and comprehensive data for public school comparisons are not yet available. To investigate the effects of single-sex education, I focus on within private sector comparisons, and additionally address…

  4. Segregation Levels in Milwaukee Public Schools and the Milwaukee Voucher Program. School Choice Issues in the State

    Science.gov (United States)

    Forster, Greg

    2006-01-01

    This study compares segregation levels in Milwaukee public schools and in private schools participating in the Milwaukee voucher program. Using a segregation index that measures the difference between the percent of students in a school who are white and the percentage of school-age children in the greater metro area who are white, it finds that…

  5. School Choice and Segregation: "Tracking" Racial Equity in Magnet Schools

    Science.gov (United States)

    Davis, Tomeka M.

    2014-01-01

    Three arguments regarding racial equity have arisen in the school choice debate. Choice advocates charge that choice will improve access to quality schools for disadvantaged minority students (Chubb & Moe 1990; Coons & Sugarman, 1978; Godwin & Kemerer, 2002; Viteritti, 1999). Critics argue that choice is unlikely to benefit minority…

  6. A comparison of the social competence of children with moderate intellectual disability in inclusive versus segregated school settings.

    Science.gov (United States)

    Hardiman, Sharon; Guerin, Suzanne; Fitzsimons, Elaine

    2009-01-01

    This is the first study to compare the social competence of children with moderate intellectual disability in inclusive versus segregated school settings in the Republic of Ireland. A convenience sample was recruited through two large ID services. The sample comprised 45 children across two groups: Group 1 (n=20; inclusive school) and Group 2 (n=25; segregated school). Parents and teachers completed the Strengths and Difficulties Questionnaire and the Adaptive Behaviour Scale-School: 2nd edition. A series of 2 x 2 ANOVAs were carried out on social competence scores using educational placement type (inclusive vs segregated school) and proxy rater (parent vs teacher) as the independent variables. Key findings indicated that children in inclusive schools did not differ significantly from children in segregated schools on the majority of proxy ratings of social competence. This supports the belief that children with intellectual disabilities can function well in different educational settings. Present findings highlight the importance of utilising the functional model of ID when selecting and designing school placements for children with moderate ID.

  7. A comparison of the social competence of children with moderate intellectual disability in inclusive versus segregated school settings.

    LENUS (Irish Health Repository)

    Hardiman, Sharon

    2009-03-01

    This is the first study to compare the social competence of children with moderate intellectual disability in inclusive versus segregated school settings in the Republic of Ireland. A convenience sample was recruited through two large ID services. The sample comprised 45 children across two groups: Group 1 (n=20; inclusive school) and Group 2 (n=25; segregated school). Parents and teachers completed the Strengths and Difficulties Questionnaire and the Adaptive Behaviour Scale-School: 2nd edition. A series of 2 x 2 ANOVAs were carried out on social competence scores using educational placement type (inclusive vs segregated school) and proxy rater (parent vs teacher) as the independent variables. Key findings indicated that children in inclusive schools did not differ significantly from children in segregated schools on the majority of proxy ratings of social competence. This supports the belief that children with intellectual disabilities can function well in different educational settings. Present findings highlight the importance of utilising the functional model of ID when selecting and designing school placements for children with moderate ID.

  8. New Jersey's Segregated Schools: Trends and Paths Forward

    Science.gov (United States)

    Orfield, Gary; Ee, Jongyeon; Coughlan, Ryan

    2017-01-01

    This report updates earlier research published by the Civil Rights Project in 2013. That report detailed troubling racial and economic segregation trends and patterns from 1989-2010. The latest report includes new data from 2010-2015. The research updates public school enrollment trends and details segregation in the state's schools by race and…

  9. Challenging Segregational Practices in a Spanish Secondary School: Results from an Ethnographic Research

    Science.gov (United States)

    Sanchez-Valero, Joan-Anton; Padilla-Petry, Paulo

    2016-01-01

    This article presents partial results of a multi-sited ethnographic study about the role of multiple literacies in young people's learning in and outside school. In one of the five participant secondary schools, fourth grade students were segregated in groups according to their special needs. We start with a critical review on segregated and…

  10. Gender Segregation in Nursery School: Predictors and Outcomes.

    Science.gov (United States)

    Maccoby, Eleanor E.; Jacklin, Carol Nagy

    Sex segregation is a powerful phenomenon in childhood. It occurs universally whenever children have a choice of playmates and is found in sub-human primates too. Adults are not directly responsible for sex segregation. Data do not support the hypothesis that the most ladylike girls and the most rough and active boys first form the segregated play…

  11. The effect of school quality on black-white health differences: evidence from segregated southern schools.

    Science.gov (United States)

    Frisvold, David; Golberstein, Ezra

    2013-12-01

    This study assesses the effect of black-white differences in school quality on black-white differences in health in later life resulting from the racial convergence in school quality for cohorts born between 1910 and 1950 in southern states with segregated schools. Using data from the 1984-2007 National Health Interview Surveys linked to race-specific data on school quality, we find that reductions in the black-white gap in school quality led to modest reductions in the black-white gap in disability.

  12. The merry-go-round of disadvantage: educational policy and integration in segregated schools

    NARCIS (Netherlands)

    de Ruiter, D.

    2008-01-01

    Segregated schools are associated with problems. Educational disadvantage among pupils at these schools persists and these kinds of schools, more than other kinds of schools, are confronted the most with societal problems. Yet little is known about what actually happens at these schools. This

  13. School Segregation and the Secondary-School Achievements of Youth in the Netherlands

    NARCIS (Netherlands)

    Sykes, Brooke; Kuyper, Hans

    2013-01-01

    This paper contributes to the literature on the relationship between school segregation and youth educational outcomes in general, and educational inequalities in particular. Using data from a longitudinal Dutch cohort study, we test whether the ethnic composition (operationalised as both ethnic

  14. Reconstructing school segregation: on the efficacy and equity of single-sex schooling

    OpenAIRE

    Billger, Sherrilyn M.

    2006-01-01

    A change to Title IX has spurred new single-sex public schooling in the US. Until recently, nearly all gender-segregated schools were private, and I therefore address potential selection bias in the effects on educational and labor market outcomes using within private sector comparisons, an index comparing expectations to outcomes, quantile regressions, and other techniques. Descriptive statistics suggest significant benefits, but more consideration of selection bias reveals less consistency....

  15. Discussing school socioeconomic segregation in territorial terms: the differentiated influence of urban fragmentation and daily mobility

    Directory of Open Access Journals (Sweden)

    Claudia Alejandra Cordoba Calquin

    2017-03-01

    Full Text Available Chile is one of the OECD countries with higher levels of socioeconomic segregation in its educational system. This may be explained by the incidence of institutional factors (fees and school selection processes, sociocultural factors (families’ appraisals and behaviors towards school choice and contextual factors, among which residential segregation would stand as the most relevant. This article analyzes the relation between school location, students’ socioeconomic status and student’s place of origin (mobility. The data used was gathered from 1613 surveys responded by primary students’ families. The results evidence that residential segregation only partially influences educational socioeconomic segregation, since the capacity of mobility is a key factor to “break” the association between both phenomena. Therefore, residential segregation would affect to a greater extent low socioeconomic status students who attend schools near their homes and travel distances shorter than children from higher socioeconomic status, who tend to cover longer distances between home and school. Nevertheless, the comparative analysis of the cases complicates drawing conclusions, because students of equal socioeconomic status travel very different distances. The characteristics of the territories where schools are located shed some light on the cause of these differences. From these results, we propose re-discussing the use of the residential segregation concept for explaining phenomena like school segregation, due to the complex interrelations between both territorial fragmentation and urban mobility.

  16. A Status Quo of Segregation: Racial and Economic Imbalance in New Jersey Schools, 1989-2010

    Science.gov (United States)

    Flaxman, Greg

    2013-01-01

    New Jersey has a curious status regarding school desegregation. It has had the nation's most venerable and strongest state law prohibiting racially segregated schooling and requiring racial balance in the schools whenever feasible. Yet, it simultaneously has had one of the worst records of racially imbalanced schools. Against the legal and…

  17. School Segregation and Resegregation in Charlotte and Raleigh, 1989-2010

    Science.gov (United States)

    Ayscue, Jennifer B.; Siegel-Hawley, Genevieve; Kucsera, John; Woodward, Brian

    2018-01-01

    Desegregated schools are linked to educational and social advantages whereas myriad harms are connected to segregated schools, yet the emphasis on school desegregation has recently receded in two North Carolina city-suburban school districts historically touted for their far-reaching efforts: Charlotte and Raleigh. In this article, we use…

  18. Measuring Between-School Segregation in an Open Enrollment System: The Case of Rio de Janeiro

    Science.gov (United States)

    Bartholo, Tiago Lisboa

    2013-01-01

    Recent research in Rio de Janeiro public schools has brought to light a "Hidden Quasi-Market" that combines purported freedom of choice for parents with school control over their pupil intake. The article analyzes patterns of segregation among schools, from 2004 to 2010, according to three indicators of potentially disadvantaged pupils:…

  19. Ethnic School Segregation and Self-Esteem: The Role of Teacher-Pupil Relationships

    Science.gov (United States)

    Agirdag, Orhan; Van Houtte, Mieke; Van Avermaet, Piet

    2012-01-01

    The authors examine whether school segregation is related to pupils' global self-esteem and whether this association is mediated by teacher-pupil relationships. Multilevel analyses based on a survey of 2,845 pupils (aged 10 to 12) in 68 primary schools in Belgian urban areas reveal that, for native-Belgian pupils, a higher proportion of immigrants…

  20. Civic Fragmentation or Voluntary Association? Habermas, Fraser, and Charter School Segregation

    Science.gov (United States)

    Wilson, Terri S.

    2010-01-01

    In this essay, Terri Wilson puts the argument developed by Kathleen Knight Abowitz that charter schools could be considered as counterpublic spaces into interaction with empirical research that explores patterns of voluntary self-segregation in charter schools. Wilson returns to the theoretical tension between Jurgen Habermas and Nancy Fraser over…

  1. Gender-Role Identity, Attitudes toward Marriage, and Gender-Segregated School Backgrounds.

    Science.gov (United States)

    Katsurada, Emiko; Sugihara, Yoko

    2002-01-01

    Investigated the relationship between Japanese college students' gender role identity and attitudes toward marriage, exploring the effects of gender-segregated school backgrounds on gender role identity and attitudes toward marriage. Women without any coeducational school background had relatively strong masculinity and desired to marry at older…

  2. Miles to Go: A Report on School Segregation in Virginia, 1989-2010

    Science.gov (United States)

    Siegel-Hawley, Genevieve

    2013-01-01

    Virginia has a long and complicated history with school desegregation efforts. It is a state that can lay claim both to advancing the goals of "Brown v. Board of Education" and to impeding them. Over the years, this history has helped shape contemporary patterns of school segregation across Virginia and in her major metropolitan areas.…

  3. An Exploration of Teacher Attrition and Mobility in High Poverty Racially Segregated Schools

    Science.gov (United States)

    Djonko-Moore, Cara M.

    2016-01-01

    The purpose of this study was to examine the mobility (movement to a new school) and attrition (quitting teaching) patterns of teachers in high poverty, racially segregated (HPRS) schools in the US. Using 2007-9 survey data from the National Center for Education Statistics, a multi-level multinomial logistic regression was performed to examine the…

  4. Income Segregation between School Districts and Inequality in Students' Achievement

    Science.gov (United States)

    Owens, Ann

    2018-01-01

    Large achievement gaps exist between high- and low-income students and between black and white students. This article explores one explanation for such gaps: income segregation between school districts, which creates inequality in the economic and social resources available in advantaged and disadvantaged students' school contexts. Drawing on…

  5. Migrant and Non-Migrant Families in Chengdu, China: Segregated Lives, Segregated Schools

    Directory of Open Access Journals (Sweden)

    Nan Li

    2015-05-01

    Full Text Available This study documented the experiences of Chinese rural-urban migrant children and their parents living in the host city of Chengdu, China. It was informed by previous studies but applied a theoretical lens cultural reproduction theory—to reveal deeper understanding of rural-urban migrant families’ lives in the city of Chengdu. Participants in this study were 10 families—10 migrant parents, 10 local Chengdu resident parents, 5 local Chengdu children, and 5 migrant children. Through qualitative interviews and observations the researchers created 5 family case studies, documenting differences and similarities in the lives of migrant and local resident families in Chengdu. Results indicated that children in the two groups experienced unequal childhoods. Although the Chinese central government has issued a number of proactive policies to allow migrant children to attend local urban public schools since 2003, the negative effect of the longstanding Hukou residency policy still impacts migrant families’ lives in Chengdu. In this article we discuss an entrenched urban-rural divide between urban residents and rural-urban migrant families, in work, community, and schooling.

  6. Socio-Economic Segregation of Disadvantaged Children between Schools in Pakistan: Comparing the State and Private Sector

    Science.gov (United States)

    Siddiqui, Nadia

    2017-01-01

    The distribution of children in different school-types and regions in Pakistan suggests that access and opportunities in education are not evenly accessible for many children. Segregation at school level is an important concern for equity and social justice because the adverse effects of segregation increase the pre-existing gap in opportunities…

  7. Education Policy and School Segregation of Migrant Students in Catalonia: The Politics of Non-Decision-Making

    Science.gov (United States)

    Bonal, Xavier

    2012-01-01

    This article shows how the Catalan government has not developed an agenda to tackle school segregation despite the growing number of migrant pupils who arrived over the course of the last decade. Education policy has explicitly disregarded the possibilities of improving the regulatory framework for tackling segregation; it has exercised…

  8. Ethnic Segregation in Friendship Networks : Studies of its Determinants in English, German, Dutch, and Swedish School Classes

    NARCIS (Netherlands)

    Smith, S.

    2015-01-01

    Adolescent interethnic friendship is an important indicator of social cohesion in multi-ethnic societies. Therefore, this dissertation examines individual, network, and contextual explanations for ethnic segregation in adolescent friendship networks in school classes. More specifically, the

  9. Effect of temperature during ion sputtering on the surface segregation rate of antimony in an iron-antimony alloy at higher temperatures

    International Nuclear Information System (INIS)

    Oku, M.; Hirokawa, K.; Kimura, H.; Suzuki, S.

    1986-01-01

    The surface segregation of antimony in an iron-0.23 at% antimony alloy was studied by XPS. The segregation rate in the temperature range between 800 and 900 K depends on the temperature during sputtering with argon ion of kinetic energy of 1 keV. The sputtering at room temperature or 473 K gives higher values of the segregation rate than those at 673 K. Both cases give the activation energy of 170 kJmol -1 for the surface segregation rate. The segregation of antimony is not observed after the sample is heated at 1000 K. (author)

  10. "Back-fire to lust": G. Stanley Hall, sex-segregated schooling, and the engine of sublimation.

    Science.gov (United States)

    Graebner, William

    2006-08-01

    G. Stanley Hall was an advocate of sex-segregated schooling long after most Americans had accepted coeducation. His position was based in part on personal experience: observations of his father and mother, a repressed and guilt-ridden boyhood sexuality, and his conviction that his own career success was a product of sublimated sexual desire, of erotic energy converted into mental energy. Hall theorized that coeducation put sublimation at risk, and that sex-segregated schools, by contributing to proper gendered development and by prolonging and sublimating the sexual tensions of adolescence, would produce social progress.

  11. Variation of mutational burden in healthy human tissues suggests non-random strand segregation and allows measuring somatic mutation rates.

    Science.gov (United States)

    Werner, Benjamin; Sottoriva, Andrea

    2018-06-01

    The immortal strand hypothesis poses that stem cells could produce differentiated progeny while conserving the original template strand, thus avoiding accumulating somatic mutations. However, quantitating the extent of non-random DNA strand segregation in human stem cells remains difficult in vivo. Here we show that the change of the mean and variance of the mutational burden with age in healthy human tissues allows estimating strand segregation probabilities and somatic mutation rates. We analysed deep sequencing data from healthy human colon, small intestine, liver, skin and brain. We found highly effective non-random DNA strand segregation in all adult tissues (mean strand segregation probability: 0.98, standard error bounds (0.97,0.99)). In contrast, non-random strand segregation efficiency is reduced to 0.87 (0.78,0.88) in neural tissue during early development, suggesting stem cell pool expansions due to symmetric self-renewal. Healthy somatic mutation rates differed across tissue types, ranging from 3.5 × 10-9/bp/division in small intestine to 1.6 × 10-7/bp/division in skin.

  12. Variation of mutational burden in healthy human tissues suggests non-random strand segregation and allows measuring somatic mutation rates.

    Directory of Open Access Journals (Sweden)

    Benjamin Werner

    2018-06-01

    Full Text Available The immortal strand hypothesis poses that stem cells could produce differentiated progeny while conserving the original template strand, thus avoiding accumulating somatic mutations. However, quantitating the extent of non-random DNA strand segregation in human stem cells remains difficult in vivo. Here we show that the change of the mean and variance of the mutational burden with age in healthy human tissues allows estimating strand segregation probabilities and somatic mutation rates. We analysed deep sequencing data from healthy human colon, small intestine, liver, skin and brain. We found highly effective non-random DNA strand segregation in all adult tissues (mean strand segregation probability: 0.98, standard error bounds (0.97,0.99. In contrast, non-random strand segregation efficiency is reduced to 0.87 (0.78,0.88 in neural tissue during early development, suggesting stem cell pool expansions due to symmetric self-renewal. Healthy somatic mutation rates differed across tissue types, ranging from 3.5 × 10-9/bp/division in small intestine to 1.6 × 10-7/bp/division in skin.

  13. IMPACT OF THE COMMUNITY SCHOOL ON PREVENTION AND CONTROL OF DELINQUENCY, SCHOOL DROPOUTS, POVERTY, RACIAL SEGREGATION.

    Science.gov (United States)

    TOTTEN, W. FRED

    THE COMMUNITY SCHOOL IS DESIGNED TO HELP PEOPLE LEARN HOW TO SOLVE THEIR OWN PROBLEMS, IT IS THE CENTER OF SERVICE FOR ALL THE PEOPLE OF A COMMUNITY REGARDLESS OF AGE, RACE, RELIGION, ETHNIC BACKGROUND, OR SOCIOECONOMIC CIRCUMSTANCES. SCHOOL FACILITIES AND SCHOOL PERSONNEL ARE AVAILABLE FOR SERVICE TO PEOPLE AT ALL TIMES OF THE DAY ON ALL DAYS OF…

  14. School Segregation and Its Effects on Educational Equality and Efficiency in 16 OECD Comprehensive School Systems

    Science.gov (United States)

    Benito, Ricard; Alegre, Miquel Àngel; Gonzàlez-Balletbò, Isaac

    2014-01-01

    Using PISA data for 16 Western OECD countries having comprehensive school systems, we explore the conditions under which the socioeconomic composition of schools affects educational efficiency and equality, to a greater or lesser extent. First, a multilevel analysis is applied to examine and compare the effect of school socioeconomic composition…

  15. Education policy and school segregation of migrant students in Catalonia: the politics of non-decision-making

    NARCIS (Netherlands)

    Bonal, X.

    2012-01-01

    This article shows how the Catalan government has not developed an agenda to tackle school segregation despite the growing number of migrant pupils who arrived over the course of the last decade. Education policy has explicitly disregarded the possibilities of improving the regulatory framework for

  16. Enclaves of opportunity or "ghettos of last resort?" Assessing the effects of immigrant segregation on violent crime rates.

    Science.gov (United States)

    Feldmeyer, Ben; Harris, Casey T; Scroggins, Jennifer

    2015-07-01

    A growing body of research indicates that immigration to the U.S. has crime-reducing effects on aggregate levels of violence, which researchers have often attributed to the protective and revitalizing effects of immigrants settling in spatially concentrated neighborhoods. However, recent scholarship suggests that growing shares of the foreign-born population are bypassing these segregated immigrant enclaves and are dispersing more widely to other urban neighborhoods. Moreover, some scholars suggest that spatially isolating immigrant populations may not always be protective, but could actually contribute to social problems like crime, particularly in disadvantaged contexts. The current study offers one of the first analyses exploring the way that segregation of immigrant populations (relative to the U.S.-born) is related to year 2000 violent crime rates for nearly 500 census places in California and New York. Results of our analysis reveal no direct link between immigrant segregation and macro-level violence, but instead show that these effects are highly contextualized and depend on the resources present in locales. Specifically, immigrant segregation contributes to violence in highly disadvantaged places but is linked to lower violence in areas with greater resources. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Authoritative School Climate and High School Dropout Rates

    Science.gov (United States)

    Jia, Yuane; Konold, Timothy R.; Cornell, Dewey

    2016-01-01

    This study tested the association between school-wide measures of an authoritative school climate and high school dropout rates in a statewide sample of 315 high schools. Regression models at the school level of analysis used teacher and student measures of disciplinary structure, student support, and academic expectations to predict overall high…

  18. The Impact of the Louisiana Scholarship Program on Racial Segregation in Louisiana Schools. Louisiana Scholarship Program Evaluation Report #3. Technical Report

    Science.gov (United States)

    Egalite, Anna J.; Mills, Jonathan N.; Wolf, Patrick J.

    2016-01-01

    The question of how school choice programs affect the racial stratification of schools is highly salient in the field of education policy. We use a student-level panel data set to analyze the impacts of the Louisiana Scholarship Program (LSP) on racial segregation in public and private schools. This targeted school voucher program provides funding…

  19. Nearly 50 Years Post-Jim Crow: Persisting and Expansive School Segregation for African American, Latina/o, and ELL Students in Texas

    Science.gov (United States)

    Vasquez Heilig, Julian; Holme, Jennifer Jellison

    2013-01-01

    This study addresses the segregation of English language learner (ELL) students in schools across Texas. We descriptively analyze levels of racial, economic, and linguistic isolation experienced by ELL students across the state of Texas. We also examine the association between segregation by race/ethnicity, economic disadvantage, and language…

  20. Childhood school segregation and later life sense of control and physical performance in the African American Health cohort.

    Science.gov (United States)

    Wolinsky, Fredric D; Andresen, Elena M; Malmstrom, Theodore K; Miller, J Philip; Schootman, Mario; Miller, Douglas K

    2012-09-27

    The association between childhood school desegregation and later life sense of control and physical performance among African Americans is not clear. We hypothesized that childhood school desegregation adversely affected the sense of control of in later life, and that this reduced sense of control accounts in part for reduced physical performance. In-home follow-up assessments were completed in 2010 with 582 of the 58-74 year old men and women participating in the on-going African American Health cohort. We used these data to examine the relationship between (a) retrospective self-reports of attending segregated schools during one's 1st-to-12th grade education and one's current sense of control, as well as (b) the association between current sense of control and physical performance. Multiple linear regression analysis with propensity score re-weighting was used. Attending segregated schools for at least half of one's 1st-to-12th grade education was significantly associated with higher scores on the sense of control. Adjusting for all covariates and potential confounders, those receiving half or more of their 1st-to-12th grade education in segregated schools had sense of control scores that were .886 points higher (p ≤ .01; standardized effect size = .22). Sense of control scores were independently (all p school segregation and physical performance. Childhood school desegregation was adversely associated with the sense of control of African Americans in later life, and this reduced sense of control appears, in part, to account for their poorer physical performance. The etiologic mechanism through which childhood school segregation at the time that this cohort experienced it improved the sense of control in later life, which subsequently led to better physical performance, has not been identified. We suspect, however, that the pathway involves greater exposure to racial solidarity, same-race students as peer role models and same-race teachers and

  1. Authoritative school climate and high school dropout rates.

    Science.gov (United States)

    Jia, Yuane; Konold, Timothy R; Cornell, Dewey

    2016-06-01

    This study tested the association between school-wide measures of an authoritative school climate and high school dropout rates in a statewide sample of 315 high schools. Regression models at the school level of analysis used teacher and student measures of disciplinary structure, student support, and academic expectations to predict overall high school dropout rates. Analyses controlled for school demographics of school enrollment size, percentage of low-income students, percentage of minority students, and urbanicity. Consistent with authoritative school climate theory, moderation analyses found that when students perceive their teachers as supportive, high academic expectations are associated with lower dropout rates. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  2. Identifying Complex Dynamics in Social Systems: A New Methodological Approach Applied to Study School Segregation

    Science.gov (United States)

    Spaiser, Viktoria; Hedström, Peter; Ranganathan, Shyam; Jansson, Kim; Nordvik, Monica K.; Sumpter, David J. T.

    2018-01-01

    It is widely recognized that segregation processes are often the result of complex nonlinear dynamics. Empirical analyses of complex dynamics are however rare, because there is a lack of appropriate empirical modeling techniques that are capable of capturing complex patterns and nonlinearities. At the same time, we know that many social phenomena…

  3. The Neighborhood Unit: Schools, Segregation, and the Shaping of the Modern Metropolitan Landscape

    Science.gov (United States)

    Erickson, Ansley T.; Highsmith, Andrew R.

    2018-01-01

    Background/Context: In the first half of the 20th century, American policy makers at all levels of government, alongside housing and real estate industry figures, crafted mechanisms of racial exclusion that helped to segregate metropolitan residential landscapes. Although educators and historians have recognized the long-term consequences of these…

  4. Pedagogic Identities for Sale! Segregation and Homogenization in Swedish Upper Secondary School

    Science.gov (United States)

    Dovemark, Marianne; Holm, Ann-Sofie

    2017-01-01

    The aim of this article is to illustrate how Swedish schools construct different pedagogic identities in the way they marketize themselves. We examine through a Bernsteinian lens how upper secondary schools promote themselves; what identities are being called for by the schools and how these identities are expressed. Moreover, the article intends…

  5. Segregation in cast products

    Indian Academy of Sciences (India)

    Unknown

    The agreement with experimental data is mostly qualitative. The paper also ... For example, a high degree of positive segregation in the central region .... solute in a cast product, important ones being: size of casting, rate of solidification, mode.

  6. New York State's Extreme School Segregation: Inequality, Inaction and a Damaged Future

    Science.gov (United States)

    Kucsera, John

    2014-01-01

    The fight for equal educational opportunity in New York has followed a pattern similar to other diverse or racially transforming states. From the 1950s to 1980s, the issue of school desegregation was an important issue. Local civil rights pressure, the courts, and legislation attempted to desegregate large urban school systems through both…

  7. School Context Matters: The Impacts of Concentrated Poverty and Racial Segregation on Childhood Obesity

    Science.gov (United States)

    Piontak, Joy Rayanne; Schulman, Michael D.

    2016-01-01

    Background: Schools are important sites for interventions to prevent childhood obesity. This study examines how variables measuring the socioeconomic and racial composition of schools and counties affect the likelihood of obesity among third to fifth grade children. Methods: Body mass index data were collected from third to fifth grade public…

  8. Innovations. Separated by Sex. A Troubled New Jersey Middle School Segregates Girls from Boys.

    Science.gov (United States)

    Richardson, Joanna

    1995-01-01

    The principal of one urban New Jersey middle school chose to deal with a long history of student behavior and discipline problems by making every class single sex. The change helped curb classroom distractions, reduced discipline problems, and restored a sense of order. (SM)

  9. Waste segregation

    International Nuclear Information System (INIS)

    Clark, D.E.; Colombo, P.

    1982-01-01

    A scoping study has been undertaken to determine the state-of-the-art of waste segregation technology as applied to the management of low-level waste (LLW). Present-day waste segregation practices were surveyed through a review of the recent literature and by means of personal interviews with personnel at selected facilities. Among the nuclear establishments surveyed were Department of Energy (DOE) laboratories and plants, nuclear fuel cycle plants, public and private laboratories, institutions, industrial plants, and DOE and commercially operated shallow land burial sites. These survey data were used to analyze the relationship between waste segregation practices and waste treatment/disposal processes, to assess the developmental needs for improved segregation technology, and to evaluate the costs and benefits associated with the implementation of waste segregation controls. This task was planned for completion in FY 1981. It should be noted that LLW management practices are now undergoing rapid change such that the technology and requirements for waste segregation in the near future may differ significantly from those of the present day. 8 figures

  10. THE IMPACT OF MASS SEGREGATION AND STAR FORMATION ON THE RATES OF GRAVITATIONAL-WAVE SOURCES FROM EXTREME MASS RATIO INSPIRALS

    Energy Technology Data Exchange (ETDEWEB)

    Aharon, Danor; Perets, Hagai B. [Physics Department, Technion—Israel Institute of Technology, Haifa 3200003 (Israel)

    2016-10-10

    Compact stellar objects inspiraling into massive black holes (MBHs) in galactic nuclei are some of the most promising gravitational-wave (GWs) sources for next-generation GW detectors. The rates of such extreme mass ratio inspirals (EMRIs) depend on the dynamics and distribution of compact objects (COs) around the MBH. Here, we study the impact of mass-segregation processes on EMRI rates. In particular, we provide the expected mass function (MF) of EMRIs, given an initial MF of stellar black holes (SBHs), and relate it to the mass-dependent detection rate of EMRIs. We then consider the role of star formation (SF) on the distribution of COs and its implication on EMRI rates. We find that the existence of a wide spectrum of SBH masses leads to the overall increase of EMRI rates and to high rates of the EMRIs from the most massive SBHs. However, it also leads to a relative quenching of EMRI rates from lower-mass SBHs, and together produces a steep dependence of the EMRI MF on the highest-mass SBHs. SF history plays a relatively small role in determining the EMRI rates of SBHs, since most of them migrate close to the MBH through mass segregation rather than forming in situ. However, the EMRI rate of neutron stars (NSs) can be significantly increased when they form in situ close to the MBH, as they can inspiral before relaxation processes significantly segregate them outward. A reverse but weaker effect of decreasing the EMRI rates from NSs and white dwarfs occurs when SF proceeds far from the MBH.

  11. United States private schools have higher rates of exemptions to school immunization requirements than public schools.

    Science.gov (United States)

    Shaw, Jana; Tserenpuntsag, Boldtsetseg; McNutt, Louise-Anne; Halsey, Neal

    2014-07-01

    To compare medical, religious, and personal belief immunization exemption rates between private and public schools in US. Exemption rates were calculated using the Centers for Disease Control and Prevention School Immunization Assessment Surveys for the 2009-2010 school year excluding states with incomplete survey data. Standardized exemption rates weighted on enrollments in public and private schools were calculated. Differences in exemption rates between public and private schools were tested using Wilcoxon signed rank test. The overall state exemption rate was higher in US private than public schools, 4.25% (SD 4.27) vs 1.91% (1.67), P = .0001 and private schools had higher exemption rates for all types of exemptions; medical 0.58% (0.71) vs 0.34% (0.34) respectively (P = .0004), religious 2.09% (3.14) vs 0.83% (1.05) respectively (P = .0001), and personal belief 6.10% (4.12) vs 2.79% (1.57), respectively (P = .006). Overall exemption rates were significantly higher in states that allowed personal belief exemptions. Exemption rates were significantly higher in US private than in public schools. Children attending private schools may be at higher risk of vaccine-preventable diseases than public school children. Copyright © 2014 Elsevier Inc. All rights reserved.

  12. A Culture of (In)Equality?: A Cross-National Study of Gender Parity and Gender Segregation in National School Systems

    Science.gov (United States)

    Wiseman, Alexander W.

    2008-01-01

    Recent international education reports have highlighted some of the progress (as well as remaining disparity) in gendered education enrollment rates. But, the problem of gender segregation is still a very real issue even in some nations where girls are enrolled at levels on par with boys. Separate classes, curricula, and in many countries separate…

  13. A Comparison of Teacher Stress and School Climate across Schools with Different Matric Success Rates

    Science.gov (United States)

    Milner, Karen; Khoza, Harriet

    2008-01-01

    Our aim was to investigate differences in teacher stress and perceptions of school climate among teachers from schools with differing matriculation success rates in the Limpopo province of South Africa. Two schools with matric pass rates of 100% and two schools with matric pass rates of less than 25% were selected from a list of schools provided…

  14. High School Graduation Rates:Alternative Methods and Implications

    OpenAIRE

    Jing Miao; Walt Haney

    2004-01-01

    The No Child Left Behind Act has brought great attention to the high school graduation rate as one of the mandatory accountability measures for public school systems. However, there is no consensus on how to calculate the high school graduation rate given the lack of longitudinal databases that track individual students. This study reviews literature on and practices in reporting high school graduation rates, compares graduation rate estimates yielded from alternative methods, and estimates d...

  15. Strong spatial segregation between wildcats and domestic cats may explain low hybridization rates on the Iberian Peninsula.

    Science.gov (United States)

    Gil-Sánchez, J M; Jaramillo, J; Barea-Azcón, J M

    2015-12-01

    The European wildcat (Felis silvestris silvestris) is an endangered felid impacted by genetic introgression with the domestic cat (Felis silvestris catus). The problem of hybridization has had different effects in different areas. In non-Mediterranean regions pure forms of wildcats became almost extinct, while in Mediterranean regions genetic introgression is a rare phenomenon. The study of the potential factors that prevent the gene flow in areas of lower hybridization may be key to wildcat conservation. We studied the population size and spatial segregation of wildcats and domestic cats in a typical Mediterranean area of ancient sympatry, where no evidence of hybridization had been detected by genetic studies. Camera trapping of wild-living cats and walking surveys of stray cats in villages were used for capture-recapture estimations of abundance and spatial segregation. Results showed (i) a low density of wildcats and no apparent presence of putative hybrids; (ii) a very low abundance of feral cats in spite of the widespread and large population sources of domestic cats inhabiting villages; (iii) strong spatial segregation between wildcats and domestic/feral cats; and (iv) no relationship between the size of the potential population sources and the abundance of feral cats. Hence, domestic cats were limited in their ability to become integrated into the local habitat of wildcats. Ecological barriers (habitat preferences, food limitations, intra-specific and intra-guild competition, predation) may explain the severe divergences of hybridization impact observed at a biogeographic level. This has a direct effect on key conservation strategies for wildcats (i.e., control of domestic cats). Copyright © 2015 Elsevier GmbH. All rights reserved.

  16. Segregation and Hispanic Homicide

    Directory of Open Access Journals (Sweden)

    Michael G. Bisciglia

    2014-01-01

    Full Text Available As the overall population of Hispanics within the United States has eclipsed that of African Americans, a mounting concern has developed regarding the rise in Hispanic lethal violence as a result of social and economic inequality. One means to measure this inequality is in the form of segregation. Research indicates that in many Hispanic communities, their levels of segregation from the White non-Hispanic population are similar to that of African Americans. Although a multitude of previous studies have looked at the impact of segregation among African Americans, the literature remains under-represented in terms of multi-city macro-level analyses among Hispanics. This current study extends the analysis of segregation’s effects on lethal violence to this population. To this end, two measures of segregation were used, the index of dissimilarity and exposure. Using data from the census and the Centers for Disease Control (CDC mortality files, negative binominal regression models were created using a sample of 236 U.S. cities. The results indicated that both measures of segregation show a strong positive influence on rates of Hispanic homicides.

  17. Are segregated sports classes scientifically justified?

    OpenAIRE

    Lawson, Sian; Hall, Edward

    2014-01-01

    School sports classes are a key part of physical and mental development, yet in many countries these classes are gender segregated. Before institutionalised segregation can be condoned it is important to tackle assumptions and check for an evidence-based rationale. This presentation aims to analyse the key arguments for segregation given in comment-form response to a recent media article discussing mixed school sports (Lawson, 2013).\\ud \\ud The primary argument given was division for strength...

  18. High School Graduation Rates:Alternative Methods and Implications

    Directory of Open Access Journals (Sweden)

    Jing Miao

    2004-10-01

    Full Text Available The No Child Left Behind Act has brought great attention to the high school graduation rate as one of the mandatory accountability measures for public school systems. However, there is no consensus on how to calculate the high school graduation rate given the lack of longitudinal databases that track individual students. This study reviews literature on and practices in reporting high school graduation rates, compares graduation rate estimates yielded from alternative methods, and estimates discrepancies between alternative results at national, state, and state ethnic group levels. Despite the graduation rate method used, results indicate that high school graduation rates in the U.S. have been declining in recent years and that graduation rates for black and Hispanic students lag substantially behind those of white students. As to graduation rate method preferred, this study found no evidence that the conceptually more complex methods yield more accurate or valid graduation rate estimates than the simpler methods.

  19. An Analysis of Florida's School Districts' Attendance Policies and their Relationship to High School Attendance Rates

    Science.gov (United States)

    Reardon, Ryan Turner

    2008-01-01

    The purpose of this non-experimental correlational study was to determine the relationship between the type of attendance policies in the high schools of the 67 Florida school districts, the size of the school district (number of high school students), the socioeconomic status SES) of the school district, and the average daily attendance rate of…

  20. Graduation Rates in South Carolina Public High Schools: The Effect of School Size and Socioeconomic Status

    Science.gov (United States)

    Rivers, Thomas E., Jr.

    2012-01-01

    This study included a comparison of the graduation rates among high schools in South Carolina closely analyzing school size and socioeconomic status. The purpose for the study was to answer two questions: What patterns and relationships exist between school size and graduation rates at high schools in South Carolina? What patterns and…

  1. 14 CFR 141.11 - Pilot school ratings.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Pilot school ratings. 141.11 Section 141.11 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) SCHOOLS AND... rating course. (x) Aircraft type rating course. (2) Special preparation courses. (Appendix K). (i) Pilot...

  2. The Effect of Minimum Wage Rates on High School Completion

    Science.gov (United States)

    Warren, John Robert; Hamrock, Caitlin

    2010-01-01

    Does increasing the minimum wage reduce the high school completion rate? Previous research has suffered from (1. narrow time horizons, (2. potentially inadequate measures of states' high school completion rates, and (3. potentially inadequate measures of minimum wage rates. Overcoming each of these limitations, we analyze the impact of changes in…

  3. Solute segregation during irradiation

    International Nuclear Information System (INIS)

    Wiedersich, H.; Okamoto, P.R.; Lam, N.Q.

    1977-01-01

    Irradiation at elevated temperature induces redistribution of the elements in alloys on a microstructural level. This phenomenon is caused by differences in the coupling of the various alloy constituents to the radiation-induced defect fluxes. A simple model of the segregation process based on coupled reaction-rate and diffusion equations is discussed. The model gives a good description of the experimentally observed consequences of radiation-induced segregation, including enrichment or depletion of solute elements near defect sinks such as surfaces, voids and dislocations; precipitation of second phases in solid solutions; precipitate redistribution in two-phase alloys; and effects of defect-production rates on void-swelling rates in alloys with minor solute additions

  4. "E Pluribus"... Separation: Deepening Double Segregation for More Students

    Science.gov (United States)

    Orfield, Gary; Kucsera, John; Siegel-Hawley, Genevieve

    2012-01-01

    This report shows segregation has increased dramatically across the country for Latino students, who are attending more intensely segregated and impoverished schools than they have for generations. The segregation increases have been the most dramatic in the West. The typical Latino student in the region attends a school where less than a quarter…

  5. A comparison of teacher stress and school climate across schools with different matric success rates

    Directory of Open Access Journals (Sweden)

    Karen Milner

    2008-05-01

    Full Text Available Our aim was to investigate differences in teacher stress and perceptions of school climate among teachers from schools with differing matriculation success rates in the Limpopo province of South Africa. Two schools with matric pass rates of 100% and two schools with matric pass rates of less than 25% were selected from a list of schools provided by the province's Educational District Circuit. The schools were matched in terms of area, size, resources, and equipment. Thirty-three teachers from the high performing schools and forty-two teachers from the poor performing schools participated in the study. Student's t tests were used to assess the differences between the schools on the variables under investigation, and the results showed the teachers' experience of stress across the different schools was not significantly different, but significant differences did emerge with regard to school climate. The implications of these findings for the study population are discussed.

  6. The american high school graduation rate : trends and levels

    OpenAIRE

    Heckman, James J.; LaFontaine, Paul A.

    2008-01-01

    This paper uses multiple data sources and a unified methodology to estimate the trends and levels of the U.S. high school graduation rate. Correcting for important biases that plague previous calculations, we establish that (a) the true high school graduation rate is substantially lower than the official rate issued by the National Center for Educational Statistics; (b) it has been declining over the past 40 years; (c) majority/minority graduation rate differentials are substantial and have n...

  7. How Did Successful High Schools Improve Their Graduation Rates?

    Science.gov (United States)

    Robertson, Janna Siegel; Smith, Robert W.; Rinka, Jason

    2016-01-01

    The researchers surveyed 23 North Carolina high schools that had markedly improved their graduation rates over the past five years. The administrators reported on the dropout prevention practices and programs to which they attributed their improved graduation rates. The majority of schools reported policy changes, especially with suspension. The…

  8. Determinants of Graduation Rate of Public Alternative Schools

    Science.gov (United States)

    Izumi, Masashi; Shen, Jianping; Xia, Jiangang

    2015-01-01

    In this study we investigated determinants of the graduation rate of public alternative schools by analyzing the most recent, nationally representative data from Schools and Staffing Survey 2007-2008. Based on the literature, we built a series of three regression models via successive block entry, predicting the graduate rate first by (a) student…

  9. Social Determinants of Overweight and Obesity Rates by Elementary School in a Predominantly Hispanic School District.

    Science.gov (United States)

    Santos, Richard; Huerta, Gabriel; Karki, Menuka; Cantarero, Andrea

    This study analyzes the social determinants associated with the overweight or obesity prevalence of 85 elementary schools during the 2010-11 academic year in a predominantly Hispanic school district. A binomial logistic regression is used to analyze the aggregate overweight or obesity rate of a school by the percent of Hispanic students in each school, selected school and neighborhood characteristics, and its geographical location. The proportion of Hispanic enrollment more readily explains a school's aggregate overweight or obesity rate than social determinants or spatial location. Number of fast food establishments and the academic ranking of a school appear to slightly impact the aggregate prevalence rate. Spatial location of school is not a significant factor, controlling for other determinants. An elementary school's overall overweight or obesity rate provides a valuable health indicator to study the social determinants of obesity among Hispanics and other students within a local neighborhood. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. CARRIAGE RATE OF ISLAMIC BOARDING SCHOOLS ( RRIAGE ...

    African Journals Online (AJOL)

    userpc

    Almajiri schools in Kano using cluster sampling. The collect ed for the presence of N. meningitides using standard cultural a further identified using latex agglutination technique. Also, Blo cts was carried out. A questionnaire was similarly administered iated with carriage status. The results of the study revealed th ldren were ...

  11. Koedukation oder Geschlechtertrennung = Coeducation or Gender Segregation.

    Science.gov (United States)

    Baumert, Jurgen

    1992-01-01

    Presents study results examining recruitment practice differences between coeducational and gender segregated secondary schools in Germany. Discusses the impact of organizational form on teacher judgments, achievement in specific subjects, school subject-related interests, and school commitment. Reports that under conditions of free school choice,…

  12. School Segregation of Immigrants and Its Effects on Educational Outcomes in Europe. EENEE Analytical Report No. 30

    Science.gov (United States)

    Brunello, Giorgio; De Paola, Maria

    2017-01-01

    This report reviews the economic literature investigating the effects of the share of immigrants in classes and schools on the school performance of immigrants and natives. The review is organized in four sections. In the first section, we document the recent expansion in the presence of immigrants in European schools, introduce a measure of…

  13. Gender Segregation: Separate but Effective?

    Science.gov (United States)

    Holthouse, David

    2010-01-01

    In 2002, only 11 public schools in the United States had gender-segregated classrooms. As of December 2009, there were more than 550. The movement is based on the hypothesis that hard-wired differences in the ways that male and female brains develop and function in childhood through adolescence require classrooms in which boys and girls are not…

  14. School Location, School Section and Students' Gender as Predictors to Secondary School Dropout Rate in Rivers State, Nigeria

    Science.gov (United States)

    Christian, Mathew

    2015-01-01

    This study was undertaken to underscore the extent the variables of school location, students' gender and school section can predict the rate of drop out of secondary school students. Ex post facto design was adopted and all data on students' enrollment, retention and completion were collected from available schools' records for two cohorts of…

  15. Surface Segregation in YSZ

    DEFF Research Database (Denmark)

    Bay, Lasse; Zachau-Christiansen, Birgit; Jacobsen, Torben

    1998-01-01

    The space charge layer formed due to segregation of yttria and oxygen ion vacancies in YSZ is described by a simple model. Effects of impurities segregation are omitted.......The space charge layer formed due to segregation of yttria and oxygen ion vacancies in YSZ is described by a simple model. Effects of impurities segregation are omitted....

  16. Segregation by onset asynchrony.

    Science.gov (United States)

    Hancock, P J B; Walton, L; Mitchell, G; Plenderleith, Y; Phillips, W A

    2008-08-05

    We describe a simple psychophysical paradigm for studying figure-ground segregation by onset asynchrony. Two pseudorandom arrays of Gabor patches are displayed, to left and right of fixation. Within one array, a subset of elements form a figure, such as a randomly curving path, that can only be reliably detected when their onset is not synchronized with that of the background elements. Several findings are reported. First, for most participants, segregation required an onset asynchrony of 20-40 ms. Second, detection was no better when the figure was presented first, and thus by itself, than when the background elements were presented first, even though in the latter case the figure could not be detected in either of the two successive displays alone. Third, asynchrony segregated subsets of randomly oriented elements equally well. Fourth, asynchronous onsets aligned with the path could be discriminated from those lying on the path but not aligned with it. Fifth, both transient and sustained neural activity contribute to detection. We argue that these findings are compatible with neural signaling by synchronized rate codes. Finally, schizophrenic disorganization is associated with reduced sensitivity. Thus, in addition to bearing upon basic theoretical issues, this paradigm may have clinical utility.

  17. The impact of realistic models of mass segregation on the event rate of extreme-mass ratio inspirals and cusp re-growth

    International Nuclear Information System (INIS)

    Amaro-Seoane, Pau; Preto, Miguel

    2011-01-01

    One of the most interesting sources of gravitational waves (GWs) for LISA is the inspiral of compact objects on to a massive black hole (MBH), commonly referred to as an 'extreme-mass ratio inspiral' (EMRI). The small object, typically a stellar black hole, emits significant amounts of GW along each orbit in the detector bandwidth. The slowly, adiabatic inspiral of these sources will allow us to map spacetime around MBHs in detail, as well as to test our current conception of gravitation in the strong regime. The event rate of this kind of source has been addressed many times in the literature and the numbers reported fluctuate by orders of magnitude. On the other hand, recent observations of the Galactic centre revealed a dearth of giant stars inside the inner parsec relative to the numbers theoretically expected for a fully relaxed stellar cusp. The possibility of unrelaxed nuclei (or, equivalently, with no or only a very shallow cusp, or core) adds substantial uncertainty to the estimates. Having this timely question in mind, we run a significant number of direct-summation N-body simulations with up to half a million particles to calibrate a much faster orbit-averaged Fokker-Planck code. We show that, under quite generic initial conditions, the time required for the growth of a relaxed, mass segregated stellar cusp is shorter than a Hubble time for MBHs with M . ∼ 6 M o-dot (i.e. nuclei in the range of LISA). We then investigate the regime of strong mass segregation (SMS) for models with two different stellar mass components. Given the most recent stellar mass normalization for the inner parsec of the Galactic centre, SMS has the significant impact of boosting the EMRI rates by a factor of ∼10 in comparison to what would result from a 7/4-Bahcall and Wolf cusp resulting in ∼250 events per Gyr per Milky Way type galaxy. Such an intrinsic rate should translate roughly into ∼10 2 -7 x 10 2 sbh's (EMRIs detected by LISA over a mission lifetime of 2 or 5

  18. Student Mobility, Segregation, and Achievement Gaps: Evidence from Clark County, Nevada

    Science.gov (United States)

    Welsh, Richard O.

    2018-01-01

    Student mobility and school segregation are two important issues with significant equity implications for urban school districts that are often addressed separately. This article examines the relationship between student mobility and school segregation. The findings indicate that more segregated schools typically have smaller within-school…

  19. The influence of ethnic segregation and school mobility in primary education on high school dropout : evidence from regression discontinuity at a contextual tipping point

    NARCIS (Netherlands)

    Ong, C.; de Witte, K.

    2013-01-01

    This paper investigates the influence of ethnic composition and school mobility at the primary school-level on the propensity to drop out of high school. Using rich school and neighbourhood administrative data, we observe that (i) frequent school movers have a 2.6 times higher likelihood of early

  20. The Relationships among the Fine Arts, School Culture, and High School Graduation Rates in Georgia

    Science.gov (United States)

    Lovett, Andrew, Jr.

    2014-01-01

    High school graduation is the single largest hurdle that students must achieve to prepare for college and career (National Governor's Association, 2011). Fleischman & Heppen (2009) agree that American high schools must address the problem of declining graduation rate. Approximately 1.28 million students drop out of high school annually (Amos,…

  1. The impact of realistic models of mass segregation on the event rate of extreme-mass ratio inspirals and cusp re-growth

    Science.gov (United States)

    Amaro-Seoane, Pau; Preto, Miguel

    2011-05-01

    One of the most interesting sources of gravitational waves (GWs) for LISA is the inspiral of compact objects on to a massive black hole (MBH), commonly referred to as an 'extreme-mass ratio inspiral' (EMRI). The small object, typically a stellar black hole, emits significant amounts of GW along each orbit in the detector bandwidth. The slowly, adiabatic inspiral of these sources will allow us to map spacetime around MBHs in detail, as well as to test our current conception of gravitation in the strong regime. The event rate of this kind of source has been addressed many times in the literature and the numbers reported fluctuate by orders of magnitude. On the other hand, recent observations of the Galactic centre revealed a dearth of giant stars inside the inner parsec relative to the numbers theoretically expected for a fully relaxed stellar cusp. The possibility of unrelaxed nuclei (or, equivalently, with no or only a very shallow cusp, or core) adds substantial uncertainty to the estimates. Having this timely question in mind, we run a significant number of direct-summation N-body simulations with up to half a million particles to calibrate a much faster orbit-averaged Fokker-Planck code. We show that, under quite generic initial conditions, the time required for the growth of a relaxed, mass segregated stellar cusp is shorter than a Hubble time for MBHs with M• boosting the EMRI rates by a factor of ~10 in comparison to what would result from a 7/4-Bahcall and Wolf cusp resulting in ~250 events per Gyr per Milky Way type galaxy. Such an intrinsic rate should translate roughly into ~102-7 × 102 sbh's (EMRIs detected by LISA over a mission lifetime of 2 or 5 years, respectively), depending on the detailed assumptions regarding LISA detection capabilities.

  2. Influence of the segregation of the granulate from the radwaste-mortar mixture from on the {sup 137}Cs leach-rate; Uticaj segregacije granulata iz sastava betonske - RAO forme na izluzivanje Cs{sup 137}

    Energy Technology Data Exchange (ETDEWEB)

    Peric, A; Plecas, I; Pavlovic, R; Pavlovic, S [Institute of Nuclear Sciences VINCA, Belgrade (Yugoslavia)

    1994-07-01

    In this paper. influence of the segregation of the granulate, presented in the radwaste-mortar matrix formulation, on the {sup 137}Cs, immobilized in the waste form, leach-rate is presented. {sup 137}Cs leach-rates of the two inspected groups of the radwaste-mortar mixture samples were compared, where the first group of the orthocylinder shaped samples was treated due to the Standard Hespe's method and the second group was treated using modified Hespe's method. In the prolonged experimental time, both groups have obtained leach-rate values that are nearly the same, striving to the saturation leach-rate values. This fact indicates that the leaching of the radionuclide as a consequence of the granulate segregation process is in same way rebuilt, as a result of the completed hydratation of the mortar matrix, and 'self healing' of the new open pores and cavities (author)

  3. Progressive segregation of the Escherichia coli chromosome

    DEFF Research Database (Denmark)

    Nielsen, Henrik Jørck; Youngren, Brenda; Hansen, Flemming G.

    2006-01-01

    We have followed the fate of 14 different loci around the Escherichia coli chromosome in living cells at slow growth rate using a highly efficient labelling system and automated measurements. Loci are segregated as they are replicated, but with a marked delay. Most markers segregate in a smooth...... temporal progression from origin to terminus. Thus, the overall pattern is one of continuous segregation during replication and is not consistent with recently published models invoking extensive sister chromosome cohesion followed by simultaneous segregation of the bulk of the chromosome. The terminus......, and a region immediately clockwise from the origin, are exceptions to the overall pattern and are subjected to a more extensive delay prior to segregation. The origin region and nearby loci are replicated and segregated from the cell centre, later markers from the various positions where they lie...

  4. The Courts, the Legislature, and Delaware's Resegregation: A Report on School Segregation in Delaware, 1989-­2010

    Science.gov (United States)

    Niemeyer, Arielle

    2014-01-01

    Delaware's history with school desegregation is complicated and contradictory. The state both advanced and impeded the goals of "Brown v. Board of Education." After implementing desegregation plans that were ineffective by design, Delaware was ultimately placed under the first metropolitan, multi-district desegregation court order in the…

  5. Gender Segregation Small Firms

    OpenAIRE

    Kenneth R Troske; William J Carrington

    1992-01-01

    This paper studies interfirm gender segregation in a unique sample of small employers. We focus on small firms because previous research on interfirm segregation has studied only large firms and because it is easier to link the demographic characteristics of employers and employees in small firms. This latter feature permits an assessment of the role of employer discrimination in creating gender segregation. Our first finding is that interfirm segregation is prevalent among small employers. I...

  6. Complex segregation analysis of blood pressure and heart rate measured before and after a 20-week endurance exercise training program: the HERITAGE Family Study.

    Science.gov (United States)

    An, P; Rice, T; Pérusse, L; Borecki, I B; Gagnon, J; Leon, A S; Skinner, J S; Wilmore, J H; Bouchard, C; Rao, D C

    2000-05-01

    Complex segregation analysis of baseline resting blood pressure (BP) and heart rate (HR) and their responses to training (post-training minus baseline) were performed in a sample of 482 individuals from 99 white families who participated in the HERITAGE Family Study. Resting BP and HR were measured at baseline and after a 20-week training program. Baseline resting BP and HR were age-adjusted and age-BMI-adjusted, and the responses to training were age-adjusted and age-baseline-adjusted, within four gender-by-generation groups. This study also analyzed the responses to training in two subsets of families: (1) the so-called "high" subsample, 45 families (216 individuals) with at least one member whose baseline resting BP is in the high end of the normal BP range (the upper 95th percentile: systolic BP [SBP] > or = 135 or diastolic BP [DBP] > or = 80 mm Hg); and (2) the so-called "nonhigh" subsample, the 54 remaining families (266 individuals). Baseline resting SBP was influenced by a multifactorial component (23%), which was independent of body mass index (BMI). Baseline resting DBP was influenced by a putative recessive locus, which accounted for 31% of the variance. In addition to the major gene effect, which may impact BMI as well, baseline resting DBP was also influenced by a multifactorial component (29%). Baseline resting HR was influenced by a putative dominant locus independent of BMI, which accounted for 31% of the variance. For the responses to training, no familiality was found in the whole sample or in the nonhigh subsample. However, in the high subsample, resting SBP response to training was influenced by a putative recessive locus, which accounted for 44% of the variance. No familiality was found for resting DBP response to training. Resting HR response to training was influenced by a major effect (accounting for 35% of the variance), with an ambiguous transmission from parents to offspring.

  7. Racial segregation patterns in selective universities

    OpenAIRE

    Peter Arcidiacono; Esteban M. Aucejo; Andrew Hussey; Kenneth Spenner

    2013-01-01

    This paper examines sorting into interracial friendships at selective universities. We show significant friendship segregation, particularly for blacks. Indeed, blacks' friendships are no more diverse in college than in high school, despite the fact that the colleges that blacks attend have substantially smaller black populations. We demonstrate that the segregation patterns occur in part because affirmative action results in large differences in the academic backgrounds of students of differ...

  8. U.S. High School Graduation Rates: Patterns and Explanations

    OpenAIRE

    Richard J. Murnane

    2013-01-01

    I survey the evidence on patterns in U.S. high school graduation rates over the period 1970–2010 and report the results of new research conducted to fill in holes in the evidence. I begin by pointing out the strengths and limitations of existing data sources. I then describe six striking patterns in graduation rates. They include stagnation over the last three decades of the twentieth century, significant race-, income-, and gender-based gaps, and significant increases in graduation rates o...

  9. THE AMERICAN HIGH SCHOOL GRADUATION RATE: TRENDS AND LEVELS*

    Science.gov (United States)

    Heckman, James J.; LaFontaine, Paul A.

    2009-01-01

    This paper applies a unified methodology to multiple data sets to estimate both the levels and trends in U.S. high school graduation rates. We establish that (a) the true rate is substantially lower than widely used measures; (b) it peaked in the early 1970s; (c) majority/minority differentials are substantial and have not converged for 35 years; (d) lower post-1970 rates are not solely due to increasing immigrant and minority populations; (e) our findings explain part of the slowdown in college attendance and rising college wage premiums; and (f) widening graduation differentials by gender help explain increasing male-female college attendance gaps. PMID:20625528

  10. THE AMERICAN HIGH SCHOOL GRADUATION RATE: TRENDS AND LEVELS.

    Science.gov (United States)

    Heckman, James J; Lafontaine, Paul A

    2010-05-01

    This paper applies a unified methodology to multiple data sets to estimate both the levels and trends in U.S. high school graduation rates. We establish that (a) the true rate is substantially lower than widely used measures; (b) it peaked in the early 1970s; (c) majority/minority differentials are substantial and have not converged for 35 years; (d) lower post-1970 rates are not solely due to increasing immigrant and minority populations; (e) our findings explain part of the slowdown in college attendance and rising college wage premiums; and (f) widening graduation differentials by gender help explain increasing male-female college attendance gaps.

  11. New Approach to reduce High School Dropout Rates

    Directory of Open Access Journals (Sweden)

    Mauricio Cristhian Portillo-Torres

    2015-05-01

    Full Text Available From 2006 to 2014, the Ministry of Public Education of Costa Rica implemented four strategic actions to reduce high school dropout rates. The main purpose of these actions was to promote student participation and student identification with their school. Studies prepared by the Ministry of Education and the Comptroller of the Republic were revised to assess the impact of these actions. The result of these actions does not show an actual decrease in the number of students who leave high school. Therefore, a more holistic view is necessary to ensure the students’ stay. This review suggests using use the concept of student engagement and applying a three tier system-wide dropout preventive actions: universal, targeted and intensive.

  12. Segregation and civic virtue

    NARCIS (Netherlands)

    Merry, M.S.

    2012-01-01

    In this essay Michael Merry defends the following prima facie argument: that civic virtue is not dependent on integration and in fact may be best fostered under conditions of segregation. He demonstrates that civic virtue can and does take place under conditions of involuntary segregation, but that

  13. Effects of racialized tracking on racial gaps in science self-efficacy, identity, engagement, and aspirations: Connection to science and school segregation

    Science.gov (United States)

    Chang, Briana L.

    Given the concentration of economic growth and power in science fields and the current levels of racial stratification in schooling, this study examined (1) the effects of race on students' connectedness to science and career aspirations, (2) the extent to which these effects were moderated by school racial composition and racialized tracking, and (3) the differences in modeling effects using separate variables for race and gender (i.e., White, Black, Hispanic, female) versus race/gender (e.g., White female, Black male, etc.). Using the lens of racial formation theory, this study situated access to science knowledge as a racial project, conferring and denying access to resources along racial lines. Reviews of the literature on science self-efficacy, identity, engagement, and career aspirations revealed an under-emphasis on school institutional factors, such as racial composition and racialized tracking (which are important in sociological literature), as shaping student outcomes. The study analyzed data from the nationally representative High School Longitudinal Study that surveyed students in 2009 during their freshman year in high school and again in 2012 during most students' junior year (n = 6,998). Affective ratings (in self-efficacy, identity, engagement) and career aspirations for students measured in 2012 were examined as dependent variables and a variable for racialized tracking was estimated given schools' placement of students in advanced science coursework in 2012. Although school racial composition was not found to moderate race on outcome effects, primary analyses demonstrated that the presence of racialized tracking in the students' schools did moderate these effects. Overall these results suggested that the student subgroups most often at a disadvantage compared to White students for the science outcomes studied were Hispanic males and females; Black students' ratings and aspirations were largely on par or exceeded those of their White counterparts

  14. Delayed high school start times later than 8:30am and impact on graduation rates and attendance rates.

    Science.gov (United States)

    McKeever, Pamela Malaspina; Clark, Linda

    2017-04-01

    The first purpose of this study was to investigate changes in high school graduation rates with a delayed school start time of later than 8:30am. The second aim of the study was to analyze the association between a delayed high school start time later than 8:30am and attendance rates. In the current study, a pre-post design using a repeated-measures analysis of variance was used to examine changes in attendance and graduation rates 2 years after a delayed start was implemented. Public high schools from 8 school districts (n=29 high schools) located throughout 7 different states. Schools were identified using previous research from the Children's National Medical Center's Division of Sleep Medicine Research Team. A total membership of more than 30,000 high school students enrolled in the 29 schools identified by the Children's National Medical Center's Research Team. A pre-post design was used for a within-subject design, controlling for any school-to-school difference in the calculation of the response variable. This is the recommended technique for a study that may include data with potential measurement error. Findings from this study linked a start time of later than 8:30am to improved attendance rates and graduation rates. Attendance rates and graduation rates significantly improved in schools with delayed start times of 8:30am or later. School officials need to take special notice that this investigation also raises questions about whether later start times are a mechanism for closing the achievement gap due to improved graduation rates. Copyright © 2017 National Sleep Foundation. Published by Elsevier Inc. All rights reserved.

  15. Plasmid segregation mechanisms

    DEFF Research Database (Denmark)

    Ebersbach, G.; Gerdes, Kenn

    2005-01-01

    Bacterial plasmids encode partitioning (par) loci that ensure ordered plasmid segregation prior to cell division. par loci come in two types: those that encode actin-like ATPases and those that encode deviant Walker-type ATPases. ParM, the actin-like ATPase of plasmid R1, forms dynamic filaments...... that segregate plasmids paired at mid-cell to daughter cells. Like microtubules, ParM filaments exhibit dynamic instability (i.e., catastrophic decay) whose regulation is an important component of the DNA segregation process. The Walker box ParA ATPases are related to MinD and form highly dynamic, oscillating...... filaments that are required for the subcellular movement and positioning of plasmids. The role of the observed ATPase oscillation is not yet understood. However, we propose a simple model that couples plasmid segregation to ParA oscillation. The model is consistent with the observed movement...

  16. Segregation and Hispanic Homicide

    OpenAIRE

    Michael G. Bisciglia

    2014-01-01

    As the overall population of Hispanics within the United States has eclipsed that of African Americans, a mounting concern has developed regarding the rise in Hispanic lethal violence as a result of social and economic inequality. One means to measure this inequality is in the form of segregation. Research indicates that in many Hispanic communities, their levels of segregation from the White non-Hispanic population ar...

  17. Rapid mass segregation in small stellar clusters

    Science.gov (United States)

    Spera, Mario; Capuzzo-Dolcetta, Roberto

    2017-12-01

    In this paper we focus our attention on small-to-intermediate N-body systems that are, initially, distributed uniformly in space and dynamically `cool' (virial ratios Q=2T/|Ω| below ˜0.3). In this work, we study the mass segregation that emerges after the initial violent dynamical evolution. At this scope, we ran a set of high precision N-body simulations of isolated clusters by means of HiGPUs, our direct summation N-body code. After the collapse, the system shows a clear mass segregation. This (quick) mass segregation occurs in two phases: the first shows up in clumps originated by sub-fragmentation before the deep overall collapse; this segregation is partly erased during the deep collapse to re-emerge, abruptly, during the second phase, that follows the first bounce of the system. In this second stage, the proper clock to measure the rate of segregation is the dynamical time after virialization, which (for cold and cool systems) may be significantly different from the crossing time evaluated from initial conditions. This result is obtained for isolated clusters composed of stars of two different masses (in the ratio mh/ml=2), at varying their number ratio, and is confirmed also in presence of a massive central object (simulating a black hole of stellar size). Actually, in stellar systems starting their dynamical evolution from cool conditions, the fast mass segregation adds to the following, slow, secular segregation which is collisionally induced. The violent mass segregation is an effect persistent over the whole range of N (128 ≤ N ≤1,024) investigated, and is an interesting feature on the astronomical-observational side, too. The semi-steady state reached after virialization corresponds to a mass segregated distribution function rather than that of equipartition of kinetic energy per unit mass as it should result from violent relaxation.

  18. Source Segregation and Collection of Source-Segregated Waste

    DEFF Research Database (Denmark)

    Christensen, Thomas Højlund; Matsufuji, Y.

    2011-01-01

    of optimal handling of the waste. But in a few cases, the waste must also be separated at source, for example removing the protective plastic cover from a commercial advertisement received by mail, prior to putting the advertisement into the waste collection bin for recyclable paper. These issues are often...... in wastes segregation addressing: - Purpose of source segregation. - Segregation criteria and guidance. - Segregation potentials and efficiencies. - Systems for collecting segregated fraction....

  19. Misleading Measurements: How Ohio School Ratings Foster False Comparisons. Executive Summary

    Science.gov (United States)

    DePaoli, Jennifer

    2014-01-01

    Policy Matters Ohio looked at schools rated the highest over a two-year period in each of Ohio's eight largest urban districts. State, school, and district data were used to examine schools--district-run and charter--that were rated Excellent or higher for either the 2010-11 or the 2011-12 school year or both. The number of schools examined ranged…

  20. Sexting Rates and Predictors From an Urban Midwest High School.

    Science.gov (United States)

    Gregg, David; Somers, Cheryl L; Pernice, Francesca Maria; Hillman, Stephen B; Kernsmith, Poco

    2018-06-01

    Risks associated with teen sexting draw increasing concern from teachers and communities as developments in communication software and devices make sharing private content faster and simpler each year. We examined rates, recipients, and predictors of teen sexting to better plan education and preventative policies and strategies. A comprehensive literature review was conducted to determine the most likely predictors of teen sexting using prior survey studies and theoretical conceptions. We surveyed 314 high school students in an urban area of a large Midwestern city. Males were found to more frequently report sexting. Impulsivity, frequency of electronic communication, peer pressure, peer sexting, and social learning significantly predicted sexting beyond age, race, and sex. Self-esteem did not moderate the effect of peer pressure to sext. Structural predictive models attained good fit to the data, and neither were moderated by sex. Sexting was highly associated with reported peer pressure, perceived norms, and impulsive decision making. Adolescents in relationships may be at particular risk of sexting. These findings will help parents, teens, and educators take appropriate measures to inform about and encourage the safe use of technology. © 2018, American School Health Association.

  1. Understanding Segregation Processes

    Science.gov (United States)

    Bruch, Elizabeth

    There is growing consensus that living in neighborhoods of concentrated poverty increases the likelihood of social problems such as teenage parenthood, drug and alcohol use, crime victimization, and chronic unemployment. Neighborhood inequality is also implicated in studies of enduring race/ethnic health disparities, and there are recent moves to broaden the definition of health care policy to policies targeting social inequality (Mechanic 2007). Residential segregation affects health outcomes in several different ways. First, income, education, and occupation are all strongly related to health (Adler and Newman 2002). Segregation is a key mechanism through which socioeconomic inequality is perpetuated and reinforced, as it hinders the upward mobility of disadvantaged groups by limiting their educational and employment opportunities. Second, segregation increases minority exposure to unhealthy neighborhood environments. Residential segregation creates areas with concentrated poverty and unemployment, both of which are key factors that predict violence and create racial differences in homicide (Samson and Wilson 1995). Neighborhood characteristics, such as exposure to environmental hazards, fear of violence, and access to grocery stores, affect health risks and health behaviors (Cheadle et al. 1991). Tobacco and alcohol industries also advertise their products disproportionately in poor, minority areas (Moore, Williams, and Qualls 1996). Finally, residential segregation leads to inequalitie in health care resources, which contributes to disparities in quality of treatment (Smedley, Stith, and Nelson 2002).

  2. Do School Budgets Matter? The Effect of Budget Referenda on Student Dropout Rates

    Science.gov (United States)

    Lee, Kyung-Gon; Polachek, Solomon W.

    2018-01-01

    This paper analyzes how changes in school expenditures affect dropout rates based on data from 466 school districts in New York during the 2003/04 to the 2007/08 school years. Past traditional regression approaches show mixed results in part because school expenditures are likely endogenous, so that one cannot disentangle cause and effect. The…

  3. A COMPREHENSIVE STUDY OF HOURLY AND DAILY SEWAGE FLOW RATES IN FLORIDA PUBLIC SCHOOLS.

    Science.gov (United States)

    FOGARTY, WILLIAM J.; REEDER, MILTON E.

    A DETERMINATION OF THE HOURLY AND DAILY SEWAGE FLOW RATES IN FLORIDA PUBLIC SCHOOLS WAS MADE TO IDENTIFY THE FLOW CHARACTERISTICS AND TO PROVIDE A MORE PRECISE BASIS FOR THE ESTABLISHMENT OF DESIGN CRITERIA FOR SEWAGE DISPOSAL FACILITIES IN SCHOOLS. WATER FLOW DATA WAS COLLECTED FOR 158 SCHOOLS AND SEWAGE FLOW DATA FROM 42 SCHOOLS. THE FINDINGS…

  4. Continuum modelling of segregating tridisperse granular chute flow

    Science.gov (United States)

    Deng, Zhekai; Umbanhowar, Paul B.; Ottino, Julio M.; Lueptow, Richard M.

    2018-03-01

    Segregation and mixing of size multidisperse granular materials remain challenging problems in many industrial applications. In this paper, we apply a continuum-based model that captures the effects of segregation, diffusion and advection for size tridisperse granular flow in quasi-two-dimensional chute flow. The model uses the kinematics of the flow and other physical parameters such as the diffusion coefficient and the percolation length scale, quantities that can be determined directly from experiment, simulation or theory and that are not arbitrarily adjustable. The predictions from the model are consistent with experimentally validated discrete element method (DEM) simulations over a wide range of flow conditions and particle sizes. The degree of segregation depends on the Péclet number, Pe, defined as the ratio of the segregation rate to the diffusion rate, the relative segregation strength κij between particle species i and j, and a characteristic length L, which is determined by the strength of segregation between smallest and largest particles. A parametric study of particle size, κij, Pe and L demonstrates how particle segregation patterns depend on the interplay of advection, segregation and diffusion. Finally, the segregation pattern is also affected by the velocity profile and the degree of basal slip at the chute surface. The model is applicable to different flow geometries, and should be easily adapted to segregation driven by other particle properties such as density and shape.

  5. Auditory stream segregation using amplitude modulated bandpass noise

    Directory of Open Access Journals (Sweden)

    Yingjiu eNie

    2015-08-01

    Full Text Available The purpose of this study was to investigate the roles of spectral overlap and amplitude modulation (AM rate for stream segregation for noise signals, as well as to test the build-up effect based on these two cues. Segregation ability was evaluated using an objective paradigm with listeners’ attention focused on stream segregation. Stimulus sequences consisted of two interleaved sets of bandpass noise bursts (A and B bursts. The A and B bursts differed in spectrum, AM-rate, or both. The amount of the difference between the two sets of noise bursts was varied. Long and short sequences were studied to investigate the build-up effect for segregation based on spectral and AM-rate differences. Results showed the following: 1. Stream segregation ability increased with greater spectral separation. 2. Larger AM-rate separations were associated with stronger segregation abilities. 3. Spectral separation was found to elicit the build-up effect for the range of spectral differences assessed in the current study. 4. AM-rate separation interacted with spectral separation suggesting an additive effect of spectral separation and AM-rate separation on segregation build-up. The findings suggest that, when normal-hearing listeners direct their attention toward segregation, they are able to segregate auditory streams based on reduced spectral contrast cues that vary by the amount of spectral overlap. Further, regardless of the spectral separation they were able to use AM-rate difference as a secondary/weaker cue. Based on the spectral differences, listeners can segregate auditory streams better as the listening duration is prolonged—i.e. sparse spectral cues elicit build-up segregation; however, AM-rate differences only appear to elicit build-up when in combination with spectral difference cues.

  6. Segregation or "Thinking Black"?: Community Activism and the Development Of Black-Focused Schools in Toronto and London, 1968-2008

    Science.gov (United States)

    Johnson, Lauri

    2013-01-01

    Background/Context: On January 29, 2008 the Toronto District School Board (TDSB) approved a city-wide Africentric elementary school under their Alternative School policy, sparking a contentious debate. Calls for Black-focused schools also arose in 2008 in London in response to the disengagement of African Caribbean youth. The historical record…

  7. Parental Choice in the Netherlands: Growing Concerns about Segregation. Sanford Working Paper Series. SAN10-02

    Science.gov (United States)

    Ladd, Helen F.; Fiske, Edward B.; Ruijs, Nienke

    2010-01-01

    The Netherlands has a long history of parental choice and school anatomy. This paper examines why segregation by educational disadvantage has only recently emerged as a policy issue in the Netherlands. In addition, we document the levels and trends of school segregation in Dutch cities. We find segregation levels that are high both absolutely and…

  8. Racial Segregation and the American Foreclosure Crisis.

    Science.gov (United States)

    Rugh, Jacob S; Massey, Douglas S

    2010-10-01

    Although the rise in subprime lending and the ensuing wave of foreclosures was partly a result of market forces that have been well-identified in the literature, in the United States it was also a highly racialized process. We argue that residential segregation created a unique niche of poor minority clients who were differentially marketed risky subprime loans that were in great demand for use in mortgage-backed securities that could be sold on secondary markets. We test this argument by regressing foreclosure actions in the top 100 U.S. metropolitan areas on measures of black, Hispanic, and Asian segregation while controlling for a variety of housing market conditions, including average creditworthiness, the extent of coverage under the Community Reinvestment Act, the degree of zoning regulation, and the overall rate of subprime lending. We find that black residential dissimilarity and spatial isolation are powerful predictors of foreclosures across U.S. metropolitan areas. In order to isolate subprime lending as the causal mechanism whereby segregation influences foreclosures, we estimate a two-stage least squares model that confirms the causal effect of black segregation on the number and rate of foreclosures across metropolitan areas. In the United States segregation was an important contributing cause of the foreclosure crisis, along with overbuilding, risky lending practices, lax regulation, and the bursting of the housing price bubble.

  9. Racial Segregation and the American Foreclosure Crisis

    Science.gov (United States)

    Rugh, Jacob S.; Massey, Douglas S.

    2013-01-01

    Although the rise in subprime lending and the ensuing wave of foreclosures was partly a result of market forces that have been well-identified in the literature, in the United States it was also a highly racialized process. We argue that residential segregation created a unique niche of poor minority clients who were differentially marketed risky subprime loans that were in great demand for use in mortgage-backed securities that could be sold on secondary markets. We test this argument by regressing foreclosure actions in the top 100 U.S. metropolitan areas on measures of black, Hispanic, and Asian segregation while controlling for a variety of housing market conditions, including average creditworthiness, the extent of coverage under the Community Reinvestment Act, the degree of zoning regulation, and the overall rate of subprime lending. We find that black residential dissimilarity and spatial isolation are powerful predictors of foreclosures across U.S. metropolitan areas. In order to isolate subprime lending as the causal mechanism whereby segregation influences foreclosures, we estimate a two-stage least squares model that confirms the causal effect of black segregation on the number and rate of foreclosures across metropolitan areas. In the United States segregation was an important contributing cause of the foreclosure crisis, along with overbuilding, risky lending practices, lax regulation, and the bursting of the housing price bubble. PMID:25308973

  10. Building a Grad Nation: Progress and Challenge in Raising High School Graduation Rates. Annual Update 2016

    Science.gov (United States)

    DePaoli, Jennifer L.; Balfanz, Robert; Bridgeland, John

    2016-01-01

    The nation has achieved an 82.3 percent high school graduation rate--a record high. Graduation rates rose for all student subgroups, and the number of low-graduation-rate high schools and students enrolled in them dropped again, indicating that progress has had far-reaching benefits for all students. This report is the first to analyze 2014…

  11. Chromosome and cell wall segregation in Streptococcus faecium ATCC 9790

    International Nuclear Information System (INIS)

    Higgins, M.L.; Glaser, D.; Dicker, D.T.; Zito, E.T.

    1989-01-01

    Segregation was studied by measuring the positions of autoradiographic grain clusters in chains formed from single cells containing on average less than one radiolabeled chromosome strand. The degree to which chromosomal and cell wall material cosegregated was quantified by using the methods of S. Cooper and M. Weinberger, dividing the number of chains labeled at the middle. This analysis indicated that in contrast to chromosomal segregation in Escherichia coli and, in some studies, to that in gram-positive rods, chromosomal segregation in Streptococcus faecium was slightly nonrandom and did not vary with growth rate. Results were not significantly affected by strand exchange. In contrast, labeled cell wall segregated predominantly nonrandomly

  12. Addition by Subtraction: The Relation Between Dropout Rates and School-Level Academic Achievement.

    Science.gov (United States)

    Glennie, Elizabeth; Bonneau, Kara; Vandellen, Michelle; Dodge, Kenneth A

    2012-01-01

    Efforts to improve student achievement should increase graduation rates. However, work investigating the effects of student-level accountability has consistently demonstrated that increases in the standards for high school graduation are correlated with increases in dropout rates. The most favored explanation for this finding is that high-stakes testing policies that mandate grade repetition and high school exit exams may be the tipping point for students who are already struggling academically. These extra demands may, in fact, push students out of school. This article examines two hypotheses regarding the relation between school-level accountability and dropout rates. The first posits that improvements in school performance lead to improved success for everyone. If school-level accountability systems improve a school for all students, then the proportion of students performing at grade level increases, and the dropout rate decreases. The second hypothesis posits that schools facing pressure to improve their overall accountability score may pursue this increase at the cost of other student outcomes, including dropout rate. Our approach focuses on the dynamic relation between school-level academic achievement and dropout rates over time-that is, between one year's achievement and the subsequent year's dropout rate, and vice versa. This article employs longitudinal data of records on all students in North Carolina public schools over an 8-year period. Analyses employ fixed-effects models clustering schools and districts within years and controls each year for school size, percentage of students who were free/reduced-price lunch eligible, percentage of students who are ethnic minorities, and locale. This study finds partial evidence that improvements in school-level academic performance will lead to improvements (i.e., decreases) in school-level dropout rates. Schools with improved performance saw decreased dropout rates following these successes. However, we find

  13. Addition by Subtraction: The Relation Between Dropout Rates and School-Level Academic Achievement

    Science.gov (United States)

    GLENNIE, ELIZABETH; BONNEAU, KARA; VANDELLEN, MICHELLE; DODGE, KENNETH A.

    2013-01-01

    Background/Context Efforts to improve student achievement should increase graduation rates. However, work investigating the effects of student-level accountability has consistently demonstrated that increases in the standards for high school graduation are correlated with increases in dropout rates. The most favored explanation for this finding is that high-stakes testing policies that mandate grade repetition and high school exit exams may be the tipping point for students who are already struggling academically. These extra demands may, in fact, push students out of school. Purpose/Objective/Focus This article examines two hypotheses regarding the relation between school-level accountability and dropout rates. The first posits that improvements in school performance lead to improved success for everyone. If school-level accountability systems improve a school for all students, then the proportion of students performing at grade level increases, and the dropout rate decreases. The second hypothesis posits that schools facing pressure to improve their overall accountability score may pursue this increase at the cost of other student outcomes, including dropout rate. Research Design Our approach focuses on the dynamic relation between school-level academic achievement and dropout rates over time—that is, between one year’s achievement and the subsequent year’s dropout rate, and vice versa. This article employs longitudinal data of records on all students in North Carolina public schools over an 8-year period. Analyses employ fixed-effects models clustering schools and districts within years and controls each year for school size, percentage of students who were free/reduced-price lunch eligible, percentage of students who are ethnic minorities, and locale. Findings/Results This study finds partial evidence that improvements in school-level academic performance will lead to improvements (i.e., decreases) in school-level dropout rates. Schools with improved

  14. Teacher Rated School Ethos and Student Reported Bullying—A Multilevel Study of Upper Secondary Schools in Stockholm, Sweden

    Science.gov (United States)

    Modin, Bitte; Låftman, Sara B.; Östberg, Viveca

    2017-01-01

    School ethos refers to the school leadership’s purposive efforts to shape and direct the attitudes, values and behaviors needed in order to promote an active learning environment and to prevent the emergence of undesirable behaviors by creating shared meaning and common goals for the school. The aim of this study was to examine how teacher rated aspects of school ethos are linked with manifestations of bullying among 11th grade students. Five teacher-rated sub-dimensions of school ethos (staff stability, teacher morale, structure-order, student focus, and academic atmosphere) were examined in relation to student-reported perpetration of and exposure to traditional school bullying and cyberbullying. The data material combines student and teacher information from two separate data collections performed in 2016, comprising teachers and students in 58 upper secondary schools in Stockholm. Analyses showed that bullying was associated with all but one of the five sub-dimensions of school ethos, namely structure and order for dealing with bullying behaviors at the school. Results are discussed in light of this counter-intuitive finding. Our findings nevertheless lend support to the idea that the social organization of schools, as reflected in their teacher-rated ethos, can affect individual students’ attitudes in a way that prevents the emergence of bullying behavior among students. PMID:29236039

  15. Teacher Rated School Ethos and Student Reported Bullying-A Multilevel Study of Upper Secondary Schools in Stockholm, Sweden.

    Science.gov (United States)

    Modin, Bitte; Låftman, Sara B; Östberg, Viveca

    2017-12-13

    School ethos refers to the school leadership's purposive efforts to shape and direct the attitudes, values and behaviors needed in order to promote an active learning environment and to prevent the emergence of undesirable behaviors by creating shared meaning and common goals for the school. The aim of this study was to examine how teacher rated aspects of school ethos are linked with manifestations of bullying among 11th grade students. Five teacher-rated sub-dimensions of school ethos (staff stability, teacher morale, structure-order, student focus, and academic atmosphere) were examined in relation to student-reported perpetration of and exposure to traditional school bullying and cyberbullying. The data material combines student and teacher information from two separate data collections performed in 2016, comprising teachers and students in 58 upper secondary schools in Stockholm. Analyses showed that bullying was associated with all but one of the five sub-dimensions of school ethos, namely structure and order for dealing with bullying behaviors at the school. Results are discussed in light of this counter-intuitive finding. Our findings nevertheless lend support to the idea that the social organization of schools, as reflected in their teacher-rated ethos, can affect individual students' attitudes in a way that prevents the emergence of bullying behavior among students.

  16. Teacher Rated School Ethos and Student Reported Bullying—A Multilevel Study of Upper Secondary Schools in Stockholm, Sweden

    Directory of Open Access Journals (Sweden)

    Bitte Modin

    2017-12-01

    Full Text Available School ethos refers to the school leadership’s purposive efforts to shape and direct the attitudes, values and behaviors needed in order to promote an active learning environment and to prevent the emergence of undesirable behaviors by creating shared meaning and common goals for the school. The aim of this study was to examine how teacher rated aspects of school ethos are linked with manifestations of bullying among 11th grade students. Five teacher-rated sub-dimensions of school ethos (staff stability, teacher morale, structure-order, student focus, and academic atmosphere were examined in relation to student-reported perpetration of and exposure to traditional school bullying and cyberbullying. The data material combines student and teacher information from two separate data collections performed in 2016, comprising teachers and students in 58 upper secondary schools in Stockholm. Analyses showed that bullying was associated with all but one of the five sub-dimensions of school ethos, namely structure and order for dealing with bullying behaviors at the school. Results are discussed in light of this counter-intuitive finding. Our findings nevertheless lend support to the idea that the social organization of schools, as reflected in their teacher-rated ethos, can affect individual students’ attitudes in a way that prevents the emergence of bullying behavior among students.

  17. Building a Grad Nation. Executive Brief: Overview of 2012-13 High School Graduation Rates

    Science.gov (United States)

    Civic Enterprises, 2015

    2015-01-01

    Over the past dozen years, schools, districts, and states have begun to focus increased attention on boosting high school graduation rates. During this period, the nation has seen more evidence-based educational reforms in low-performing schools, more support for struggling students, and better data and stronger accountability to chart progress…

  18. Dropout Prevention: A Study of Prevention Programs Used by High Schools to Increase Graduation Rate

    Science.gov (United States)

    Simmons, Christopher L.

    2013-01-01

    This mixed methods study focused on the relationship between dropout prevention programs and graduation rates in one school district in Florida during the 2010-2011 school year. The dropout prevention program data analyzed included high school principals' perceptions in regard to perceived effectiveness, fidelity of implementation, cost efficacy,…

  19. Metabolic rate and clothing insulation data of children and adolescents during various school activities

    NARCIS (Netherlands)

    Havenith, G.

    2007-01-01

    Data on metabolic rates (n = 0;81) and clothing insulation (n = 96) of school children and adolescents (A, primary school: age 9-10; B, primary school: age 10-11 year; C, junior vocational (technical) education: age 13-16 (lower level); D, same as C but at advanced level; and E, senior vocational

  20. Applied Thermodynamics: Grain Boundary Segregation

    Directory of Open Access Journals (Sweden)

    Pavel Lejček

    2014-03-01

    Full Text Available Chemical composition of interfaces—free surfaces and grain boundaries—is generally described by the Langmuir–McLean segregation isotherm controlled by Gibbs energy of segregation. Various components of the Gibbs energy of segregation, the standard and the excess ones as well as other thermodynamic state functions—enthalpy, entropy and volume—of interfacial segregation are derived and their physical meaning is elucidated. The importance of the thermodynamic state functions of grain boundary segregation, their dependence on volume solid solubility, mutual solute–solute interaction and pressure effect in ferrous alloys is demonstrated.

  1. Cohort Graduation Rate: Policy and Technical Manual. 2016-17 Graduation Rates Based on Students First Entering High School during the 2012-13 and 2013-14 School Years

    Science.gov (United States)

    Oregon Department of Education, 2017

    2017-01-01

    High School graduation rates are key indicators of accountability for high schools and school districts in Oregon. Beginning with the 2008-09 school year, the Oregon Department of Education (ODE) implemented the cohort method of calculating graduation rates. The cohort method identifies the year the student entered high school for the first time…

  2. Segregation in Religion Networks

    OpenAIRE

    Hu, Jiantao; Zhang, Qian-Ming; Zhou, Tao

    2018-01-01

    Religious beliefs could facilitate human cooperation [1-6], promote civic engagement [7-10], improve life satisfaction [11-13] and even boom economic development [14-16]. On the other side, some aspects of religion may lead to regional violence, intergroup conflict and moral prejudice against atheists [17-23]. Analogous to the separation of races [24], the religious segregation is a major ingredient resulting in increasing alienation, misunderstanding, cultural conflict and even violence amon...

  3. The Impact of Tobacco-Free School Policies on Youth Smoking Rates in Florida Public School Districts.

    Science.gov (United States)

    Terry, Amanda; Zhang, Ning Jackie

    2016-02-01

    Developing and implementing policies to curb and prevent youth tobacco use is of the utmost importance. In Florida, public school districts were authorized to develop tobacco-free school policies through an amendment to the Florida Clean Indoor Air Act in 2011. The purpose of this study is to determine the impact of tobacco-free school policies on smoking rates among youth in Florida. Analysis of covariance (ANCOVA) and a multiple regression analysis were used to determine whether the comprehensiveness and enforcement of tobacco-free school policies affect the youth smoking rates within Florida public school districts. The 2010 and 2014 youth smoking rates were calculated based on the Florida Youth Tobacco Survey results. The 2010 youth smoking rate and the inclusion of the enforcement component with provision of cessation resources were statistically significant predictors of the 2014 youth smoking rate. However, the comprehensiveness level of a policy and the inclusion of an enforcement component were not statistically significant predictors. The inclusion of an enforcement component with provision of cessation resources is important in efforts to reduce youth smoking rates. The content of the tobacco-free school policies seems to be less relevant to their effectiveness than the enforcement of the policies. © 2016, American School Health Association.

  4. Micro and Macro Segregation in Alloys Solidifying with Equiaxed Morphology

    Science.gov (United States)

    Stefanescu, Doru M.; Curreri, Peter A.; Leon-Torres, Jose; Sen, Subhayu

    1996-01-01

    To understand macro segregation formation in Al-Cu alloys, experiments were run under terrestrial gravity (1g) and under low gravity during parabolic flights (10(exp -2) g). Alloys of two different compositions (2% and 5% Cu) were solidified at two different cooling rates. Systematic microscopic and SEM observations produced microstructural and segregation maps for all samples. These maps may be used as benchmark experiments for validation of microstructure evolution and segregation models. As expected, the macro segregation maps are very complex. When segregation was measured along the central axis of the sample, the highest macro segregation for samples solidified at 1g was obtained for the lowest cooling rate. This behavior is attributed to the longer time available for natural convection and shrinkage flow to affect solute redistribution. In samples solidified under low-g, the highest macro-segregation was obtained at the highest cooling rate. In general, low-gravity solidification resulted in less segregation. To explain the experimental findings, an analytical (Flemings-Nereo) and a numerical model were used. For the numerical model, the continuum formulation was employed to describe the macroscopic transports of mass, energy, and momentum, associated with the microscopic transport phenomena, for a two-phase system. The model proposed considers that liquid flow is driven by thermal and solutal buoyancy, and by solidification shrinkage. The Flemings-Nereo model explains well macro segregation in the initial stages of low-gravity segregation. The numerical model can describe the complex macro segregation pattern and the differences between low- and high-gravity solidification.

  5. Statewide prevalence of school children at risk of anaphylaxis and rate of adrenaline autoinjector activation in Victorian government schools, Australia.

    Science.gov (United States)

    Loke, Paxton; Koplin, Jennifer; Beck, Cara; Field, Michael; Dharmage, Shyamali C; Tang, Mimi L K; Allen, Katrina J

    2016-08-01

    The prevalence of school students at risk of anaphylaxis in Victoria is unknown and has not been previously studied. Similarly, rates of adrenaline autoinjector usage in the school environment have yet to be determined given increasing prescription rates. We sought to determine time trends in prevalence of school children at risk of anaphylaxis across all year levels and the annual usage rate of adrenaline autoinjectors in the school setting relative to the number of students at risk of anaphylaxis. Statewide surveys from more than 1,500 government schools including more than 550,000 students were used and prevalence rates (%) with 95% CIs were calculated. The overall prevalence of students at risk of anaphylaxis has increased 41% from 0.98% (95% CI, 0.95-1.01) in 2009 to 1.38% (95% CI, 1.35-1.41) in 2014. There was a significant drop in reporting of anaphylaxis risk with transition from the final year of primary school to the first year of secondary school, suggesting a change in parental reporting of anaphylaxis risk among secondary school students. The number of adrenaline autoinjectors activated per 1000 students at risk of anaphylaxis ranged from 6 to 8 per year, with consistently higher activation use in secondary school students than in primary school students. Statewide prevalence of anaphylaxis risk has increased in children attending Victorian government schools. However, adrenaline autoinjector activation has remained fairly stable despite known increase in the rates of prescription. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  6. The High Cost of South Carolina's Low Graduation Rate. School Choice Issues in the State

    Science.gov (United States)

    Gottlob, Brian J.

    2007-01-01

    Research has documented a crisis in South Carolina's high school graduation rate. While state officials report a graduation rate above 70 percent, researchers from South Carolina and elsewhere place the rate just above 50 percent, with rates among minority students lower than 50 percent. South Carolina's graduation rate is the worst of all 50…

  7. Contextualising Inequalities in Rates of School Exclusion in English Schools: Beneath the "Tip of the Ice-Berg"

    Science.gov (United States)

    Gazeley, Louise; Marrable, Tish; Brown, Chris; Boddy, Janet

    2015-01-01

    There is an increasing emphasis internationally on better understanding the links between inequalities and processes within school systems. In England there has been a particular focus on rates of school exclusion because the national data has consistently highlighted troubling patterns of over-representation. This paper argues that a move away…

  8. Increasing the admission rate to upper secondary school

    DEFF Research Database (Denmark)

    Hoest, A.; Jensen, V.M.; Nielsen, L.P.

    2013-01-01

    Although several studies investigate the effects of school resources on student performance, these studies tend to focus more on intervention effect sizes than on their cost-effectiveness. Exploiting policy-induced variation in Denmark and using high-quality administrative data, we investigate...... to upper secondary school between 4.0 and 6.3 percentage points for immigrants, but shows at best small improvements for the native students....

  9. "A Few of the Brightest, Cleanest Mexican Children": School Segregation as a Form of Mundane Racism in Oxnard, California, 1900-1940

    Science.gov (United States)

    Garcia, David G.; Yosso, Tara J.; Barajas, Frank P.

    2012-01-01

    In this article, David G. Garcia, Tara J. Yosso, and Frank P. Barajas examine the early twentieth-century origins of a dual schooling system that facilitated the reproduction of a cheap labor force and the marginalization of Mexicans in Oxnard, California. In their analysis of the 1930s Oxnard Elementary School District board minutes, alongside…

  10. National High School Graduation Rate: Are Recent Birth Cohorts Taking More Time to Graduate?

    Science.gov (United States)

    Joo, Myungkook; Kim, Jeounghee

    2016-01-01

    Debates about the national high school graduation rate have heated up as various national high school graduation estimates based on the Common Core of Data (CCD) and the Current Population Survey (CPS) do not coincide with one another partially due to different assumptions about graduation age. This study found that (a) while graduation rate by…

  11. The Effect of Selected Nonmusical Factors on Adjudicators' Ratings of High School Solo Vocal Performances

    Science.gov (United States)

    Howard, Sandra A.

    2012-01-01

    The purpose of this study was to examine the effect of differentiated performance attire and stage deportment on adjudicators' ratings of high school solo vocal performances. High school choral students (n = 153) and undergraduate (n = 97) and graduate music majors (n = 32) served as adjudicators (N = 282). Adjudicators rated recorded solo vocal…

  12. What explains between-school differences in rates of sexual experience?

    Directory of Open Access Journals (Sweden)

    Williamson Lisa

    2008-02-01

    Full Text Available Abstract Background Schools have the potential to influence their pupils' behaviour through the school's social organisation and culture, as well as through the formal curriculum. This paper provides the first attempt to explain the differences between schools in rates of reported heterosexual sexual experience amongst 15 and 16 year olds. It first examined whether variations in rates of sexual experience remained after controlling for the known predictors of sexual activity. It then examined whether these residuals, or 'school effects', were attributable to processes within the school, or were more likely to reflect characteristics of the neighbourhood. Methods Longitudinal survey data from 4,926 pupils in 24 Scottish schools were linked to qualitative and quantitative data on school processes including quality of relationships (staff-pupil, etc, classroom discipline, organisation of Personal and Social Education, school appearance and pupil morale. Multi-level modelling was used to test a range of models and the resulting 'school effects' were then interpreted using the process data. Results Overall, 42% of girls and 33% of boys reported experience of sexual intercourse, with rates by school ranging from 23% to 61%. When individual socio-economic and socio-cultural factors were taken into account the school variation dropped sharply, though pupils' attitudes and aspirations had little effect. There was very little correlation between boys' and girls' rates of sexual experience by school, after controlling for known predictors of sexual activity. Girls were more influenced by individual socio-economic factors than boys. School-level socio-economic factors were predictive even after taking account of individual socio-cultural factors, suggesting that the wider socio-economic environment further influenced young people's sexual experience. Conclusion Importantly, school processes did not explain the variation between schools in sexual experience

  13. Liquid Segregation Phenomenological Behaviors of Ti14 Alloy during Semisolid Deformation

    Directory of Open Access Journals (Sweden)

    Y. N. Chen

    2014-05-01

    Full Text Available The liquid segregation phenomenon and its effect on deformation mechanism of Ti14 alloy in semisolid metal processing were investigated by thermal simulation test. Microstructure of depth profile was determined by cross-section quantitative metallography, and liquid segregation phenomenon was described by Darcy's law. The results show that segregation phenomenon was affected by solid fraction, strain rate, and deformation rate. More liquid segregated from center to edge portion with high strain rate and/or deformation ratio as well as low solid fraction, which caused different distribution of dominating deformation mechanism. The relationship between liquid segregation and main deformation mechanism was also discussed by phenomenological model.

  14. Asymmetric strand segregation: epigenetic costs of genetic fidelity?

    Directory of Open Access Journals (Sweden)

    Diane P Genereux

    2009-06-01

    Full Text Available Asymmetric strand segregation has been proposed as a mechanism to minimize effective mutation rates in epithelial tissues. Under asymmetric strand segregation, the double-stranded molecule that contains the oldest DNA strand is preferentially targeted to the somatic stem cell after each round of DNA replication. This oldest DNA strand is expected to have fewer errors than younger strands because some of the errors that arise on daughter strands during their synthesis fail to be repaired. Empirical findings suggest the possibility of asymmetric strand segregation in a subset of mammalian cell lineages, indicating that it may indeed function to increase genetic fidelity. However, the implications of asymmetric strand segregation for the fidelity of epigenetic information remain unexplored. Here, I explore the impact of strand-segregation dynamics on epigenetic fidelity using a mathematical-modelling approach that draws on the known molecular mechanisms of DNA methylation and existing rate estimates from empirical methylation data. I find that, for a wide range of starting methylation densities, asymmetric -- but not symmetric -- strand segregation leads to systematic increases in methylation levels if parent strands are subject to de novo methylation events. I found that epigenetic fidelity can be compromised when enhanced genetic fidelity is achieved through asymmetric strand segregation. Strand segregation dynamics could thus explain the increased DNA methylation densities that are observed in structured cellular populations during aging and in disease.

  15. Patterns of Residential Segregation.

    Directory of Open Access Journals (Sweden)

    Rémi Louf

    Full Text Available The spatial distribution of income shapes the structure and organisation of cities and its understanding has broad societal implications. Despite an abundant literature, many issues remain unclear. In particular, all definitions of segregation are implicitely tied to a single indicator, usually rely on an ambiguous definition of income classes, without any consensus on how to define neighbourhoods and to deal with the polycentric organization of large cities. In this paper, we address all these questions within a unique conceptual framework. We avoid the challenge of providing a direct definition of segregation and instead start from a definition of what segregation is not. This naturally leads to the measure of representation that is able to identify locations where categories are over- or underrepresented. From there, we provide a new measure of exposure that discriminates between situations where categories co-locate or repel one another. We then use this feature to provide an unambiguous, parameter-free method to find meaningful breaks in the income distribution, thus defining classes. Applied to the 2014 American Community Survey, we find 3 emerging classes-low, middle and higher income-out of the original 16 income categories. The higher-income households are proportionally more present in larger cities, while lower-income households are not, invalidating the idea of an increased social polarisation. Finally, using the density-and not the distance to a center which is meaningless in polycentric cities-we find that the richer class is overrepresented in high density zones, especially for larger cities. This suggests that density is a relevant factor for understanding the income structure of cities and might explain some of the differences observed between US and European cities.

  16. Earlier school start times are associated with higher rates of behavioral problems in elementary schools.

    Science.gov (United States)

    Keller, Peggy S; Gilbert, Lauren R; Haak, Eric A; Bi, Shuang; Smith, Olivia A

    2017-04-01

    Early school start times may curtail children's sleep and inadvertently promote sleep restriction. The current study examines the potential implications for early school start times for behavioral problems in public elementary schools (student ages 5-12 years) in Kentucky. School start times were obtained from school Web sites or by calling school offices; behavioral and disciplinary problems, along with demographic information about schools, were obtained from the Kentucky Department of Education. Estimated associations controlled for teacher/student ratio, racial composition, school rank, enrollment, and Appalachian location. Associations between early school start time and greater behavioral problems (harassment, in-school removals, suspensions, and expulsions) were observed, although some of these associations were found only for schools serving the non-Appalachian region. Findings support the growing body of research showing that early school start times may contribute to student problems, and extend this research through a large-scale examination of elementary schools, behavioral outcomes, and potential moderators of risk. Copyright © 2017 National Sleep Foundation. Published by Elsevier Inc. All rights reserved.

  17. Waiving Away High School Graduation Rate Accountability? Policy Brief

    Science.gov (United States)

    Alliance for Excellent Education, 2012

    2012-01-01

    In November 2011, eleven states submitted applications to the U.S. Department of Education (ED) for waivers from key provisions of the No Child Left Behind Act. Although the waiver process presents an opportunity to strengthen college and career readiness among the nation's high school students, this analysis by the Alliance for Excellent…

  18. Does School Choice Increase the Rate of Youth Entrepreneurship?

    Science.gov (United States)

    Sobel, Russell S.; King, Kerry A.

    2008-01-01

    Because entrepreneurial activity is a key source of economic growth, promoting youth entrepreneurship has become a priority for policymakers. School choice programs force administrators and teachers to be more entrepreneurial in their jobs by encouraging innovation and by creating competition and a more business-like environment in K-12 education.…

  19. Healthier Standards for School Meals and Snacks: Impact on School Food Revenues and Lunch Participation Rates.

    Science.gov (United States)

    Cohen, Juliana F W; Gorski, Mary T; Hoffman, Jessica A; Rosenfeld, Lindsay; Chaffee, Ruth; Smith, Lauren; Catalano, Paul J; Rimm, Eric B

    2016-10-01

    In 2012, the updated U.S. Department of Agriculture school meals standards and a competitive food law similar to the fully implemented version of the national Smart Snack standards went into effect in Massachusetts. This study evaluated the impact of these updated school meal standards and Massachusetts' comprehensive competitive food standards on school food revenues and school lunch participation. Revenue and participation data from 11 Massachusetts school districts were collected from 2011 to 2014 and analyzed in 2015 using multilevel modeling. The association between the change in compliance with the competitive food standards and revenues/participation was assessed using linear regression. Schools experienced declines in school food revenues of $15.40/student in Year 1 from baseline (p=0.05), due to competitive food revenue losses. In schools with 3 years of data, overall revenues rebounded by the second year post-implementation. Additionally, by Year 2, school lunch participation increased by 15% (p=0.0006) among children eligible for reduced-price meals. Better competitive food compliance was inversely associated with school food revenues in the first year only; an absolute change in compliance by 10% was associated with a $9.78/student decrease in food revenues over the entire school year (p=0.04). No association was seen between the change in compliance and school meal participation. Schools experienced initial revenue losses after implementation of the standards, yet longer-term school food revenues were not impacted and school meal participation increased among children eligible for reduced-price meals. Weakening the school meal or competitive food guidelines based on revenue concerns appears unwarranted. Copyright © 2016 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

  20. Evidence-Based Adequacy Model for School Funding: Success Rates in Illinois Schools that Meet Targets

    Science.gov (United States)

    Murphy, Gregory J.

    2012-01-01

    This quantitative study explores the 2010 recommendation of the Educational Funding Advisory Board to consider the Evidence-Based Adequacy model of school funding in Illinois. This school funding model identifies and costs research based practices necessary in a prototypical school and sets funding levels based upon those practices. This study…

  1. Sex segregation in undergraduate engineering majors

    Science.gov (United States)

    Litzler, Elizabeth

    Gender inequality in engineering persists in spite of women reaching parity in college enrollments and degrees granted. To date, no analyses of educational sex segregation have comprehensively examined segregation within one discipline. To move beyond traditional methods of studying the long-standing stratification by field of study in higher education, I explore gender stratification within one field: engineering. This dissertation investigates why some engineering disciplines have a greater representation of women than other engineering disciplines. I assess the individual and institutional factors and conditions associated with women's representation in certain engineering departments and compare the mechanisms affecting women's and men's choice of majors. I use national data from the Engineering Workforce Commission, survey data from 21 schools in the Project to Assess Climate in Engineering study, and Carnegie Foundation classification information to study sex segregation in engineering majors from multiple perspectives: the individual, major, institution, and country. I utilize correlations, t-tests, cross-tabulations, log-linear modeling, multilevel logistic regression and weighted least squares regression to test the relative utility of alternative explanations for women's disproportionate representation across engineering majors. As a whole, the analyses illustrate the importance of context and environment for women's representation in engineering majors. Hypotheses regarding hostile climate and discrimination find wide support across different analyses, suggesting that women's under-representation in certain engineering majors is not a question of choice or ability. However, individual level factors such as having engineering coursework prior to college show an especially strong association with student choice of major. Overall, the analyses indicate that institutions matter, albeit less for women, and women's under-representation in engineering is not

  2. Waste segregation procedures and benefits

    International Nuclear Information System (INIS)

    Fish, J.D.; Massey, C.D.; Ward, S.J.

    1990-01-01

    Segregation is a critical first step in handling hazardous and radioactive materials to minimize the generation of regulated wastes. In addition, segregation can significantly reduce the complexity and the total cost of managing waste. Procedures at Sandia National Laboratories, Albuquerque require that wastes be segregated, first, by waste type (acids, solvents, low level radioactive, mixed, classified, etc.). Higher level segregation requirements, currently under development, are aimed at enhancing the possibilities for recovery, recycle and reapplication; reducing waste volumes; reducing waste disposal costs, and facilitating packaging storage, shipping and disposal. 2 tabs

  3. Conditions for spatial segregation: some European perspectives.

    NARCIS (Netherlands)

    Musterd, S.; de Winter, M.

    1998-01-01

    Evaluates some theses on the theme of spatial segregation in Europe. Spatial segregation as an important issue on the political agendas of European nations; Two views of segregation in Europe; Strategies of European nations to deal with segregation; Segregation in European cities

  4. The effect of school dismissal on rates of influenza-like illness in New York City schools during the spring 2009 novel H1N1 outbreak.

    Science.gov (United States)

    Egger, Joseph R; Konty, Kevin J; Wilson, Elisha; Karpati, Adam; Matte, Thomas; Weiss, Don; Barbot, Oxiris

    2012-03-01

    The effects of individual school dismissal on influenza transmission have not been well studied. During the spring 2009 novel H1N1 outbreak, New York City implemented an individual school dismissal policy intended to limit influenza transmission at schools with high rates of influenza-like illness (ILI). Active disease surveillance data collected by the New York City Health Department on rates of ILI in schools were used to evaluate the impact. Sixty-four schools that met the Health Department's criteria for considering dismissal were included in the analysis. Twenty-four schools that met criteria subsequently dismissed all classes for approximately 1 school week. A regression model was fit to these data, estimating the effect of school dismissal on rates of in-school ILI following reconvening, adjusting for potential confounders. The model estimated that, on average, school dismissal reduced the rate of ILI by 7.1% over the entire average outbreak period. However, a large proportion of in-school ILI occurred before dismissal criteria were met. A separate model estimated that school absenteeism rates were not significantly affected by dismissal. Results suggest that individual school dismissal could be considered in situations where schools have a disproportionate number of high-risk students or may be unable to implement recommended preventive or infection control measures. Future work should focus on developing more sensitive indicators of early outbreak detection in schools and evaluating the impact of school dismissal on community transmission. © 2012, American School Health Association.

  5. The Impact of Low, Moderate, and High Military Family Mobility School District Transfer Rates on Graduating Senior High School Dependents' Achievement and School Engagement

    Science.gov (United States)

    Rippe, Jeffrey K.

    2012-01-01

    The results of this study suggest that there were no significant differences in the academic performance of military dependents' with low (n = 20), moderate (n = 20), and high (n = 20) mobility school district transfer rates compared to non-military control students (n = 20) before completing high school. The findings were not consistent with…

  6. Federal High School Graduation Rate Policies and the Impact on Georgia

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

  7. Federal High School Graduation Rate Policies and the Impact on New Mexico

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

  8. Federal High School Graduation Rate Policies and the Impact on Nebraska

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

  9. Federal High School Graduation Rate Policies and the Impact on Hawaii

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

  10. Federal High School Graduation Rate Policies and the Impact on Mississippi

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

  11. Federal High School Graduation Rate Policies and the Impact on Illinois

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

  12. Federal High School Graduation Rate Policies and the Impact on California

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

  13. Federal High School Graduation Rate Policies and the Impact on New York

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

  14. Federal High School Graduation Rate Policies and the Impact on Colorado

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

  15. Federal High School Graduation Rate Policies and the Impact on Indiana

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

  16. Federal High School Graduation Rate Policies and the Impact on Arizona

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

  17. Federal High School Graduation Rate Policies and the Impact on Louisiana

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

  18. Federal High School Graduation Rate Policies and the Impact on Michigan

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

  19. Federal High School Graduation Rate Policies and the Impact on Connecticut

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

  20. Federal High School Graduation Rate Policies and the Impact on Delaware

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

  1. Federal High School Graduation Rate Policies and the Impact on Florida

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

  2. Federal High School Graduation Rate Policies and the Impact on Arkansas

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

  3. Federal High School Graduation Rate Policies and the Impact on New Hampshire

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

  4. Federal High School Graduation Rate Policies and the Impact on Maine

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

  5. Federal High School Graduation Rate Policies and the Impact on Alaska

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

  6. Federal High School Graduation Rate Policies and the Impact on Minnesota

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

  7. Federal High School Graduation Rate Policies and the Impact on Alabama

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

  8. Federal High School Graduation Rate Policies and the Impact on New Jersey

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

  9. Federal High School Graduation Rate Policies and the Impact on Nevada

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

  10. Federal High School Graduation Rate Policies and the Impact on Massachusetts

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

  11. Federal High School Graduation Rate Policies and the Impact on Montana

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

  12. High School Diploma Options That Meet Federal Graduation Rate Calculation Requirements. Education Trends

    Science.gov (United States)

    Zinth, Jennifer

    2018-01-01

    Federal requirements stipulate that states and local education agencies annually calculate and report an Adjusted Cohort Graduation Rate, disaggregated by student group. The ACGR includes all students who graduate from high school in four years with a regular high school diploma, plus all students with the most significant cognitive disabilities…

  13. Federal High School Graduation Rate Policies and the Impact on Missouri

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

  14. Federal High School Graduation Rate Policies and the Impact on Maryland

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

  15. Federal High School Graduation Rate Policies and the Impact on Kansas

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

  16. Federal High School Graduation Rate Policies and the Impact on Idaho

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

  17. Federal High School Graduation Rate Policies and the Impact on Kentucky

    Science.gov (United States)

    Alliance for Excellent Education, 2009

    2009-01-01

    In today's economy, employers increasingly demand that workers have a high school diploma, yet America's graduation rates are unacceptably low, particularly among poor and minority students. Nationally, only about 70 percent of students graduate from high school on time with a regular diploma; for African American and Hispanic students, this…

  18. Explaining the Gap in Charter and Traditional Public School Teacher Turnover Rates

    Science.gov (United States)

    Stuit, David A.; Smith, Thomas M.

    2012-01-01

    This study uses national survey data to examine why charter school teachers are more likely to turnover than their traditional public school counterparts. We test whether the turnover gap is explained by different distributions of factors that are empirically and theoretically linked to turnover risk. We find that the turnover rate of charter…

  19. Sickness Absenteeism Rate in Iranian Schools during the 2009 Epidemic of Type a Influenza

    Science.gov (United States)

    Pourabbasi, Ata; Shirvani, Mahbubeh Ebrahimnegad; Khashayar, Patricia

    2012-01-01

    Influenza pandemic was a global event in 2009 and intraschool transmission was its main spread method. The present study was designed to evaluate the absenteeism rate during the type A influenza epidemic. Four hundred and eight students from both a guidance school and high school in the Iranian capital were recruited in this retrospective study.…

  20. 78 FR 51597 - Modernizing the E-Rate Program for Schools and Libraries

    Science.gov (United States)

    2013-08-20

    ... this goal would be benchmarking the performance of schools' and libraries' broadband connections... Modernizing the E-Rate Program for Schools and Libraries; Proposed Rule #0;#0;Federal Register / Vol. 78 , No... Libraries AGENCY: Federal Communications Commission. ACTION: Proposed rule. SUMMARY: In this document, the...

  1. The Prevalent Rate of Problem-Solving Approach in Teaching Mathematics in Ghanaian Basic Schools

    Science.gov (United States)

    Nyala, Joseph; Assuah, Charles; Ayebo, Abraham; Tse, Newel

    2016-01-01

    Stakeholders of mathematics education decry the rate at which students' performance are falling below expectation; they call for a shift to practical methods of teaching the subject in Ghanaian basic schools. The study explores the extent to which Ghanaian basic school mathematics teachers use problem-solving approach in their lessons. The…

  2. An Analysis of a Plan to Improve Graduation Rates in Johnston County Schools

    Science.gov (United States)

    Renfrow, David Ross

    2015-01-01

    There have been limited qualitative case studies exploring effective strategies designed to improve graduation rates in rural school districts. Specifically, few studies have presented information based solely upon the voices of practitioners themselves in solving the graduation crisis in America's public schools. This study will add to the…

  3. Transitioning to the New High School Graduation Rate. Policy on Point

    Science.gov (United States)

    Lenard, Matthew

    2011-01-01

    For nearly a decade, states have had flexibility in collecting and reporting graduation rate data for state and federal accountability purposes. But in 2008, the U.S. Department of Education issued new guidelines that require all states to report a new rate--the four-year adjusted cohort graduation rate--beginning in the 2011-2012 school year.…

  4. Some Further Evidence on the Rate of Return to Schooling and the Business Cycle.

    Science.gov (United States)

    King, Randall H.

    1980-01-01

    The business cycle has a strong impact on calculated rates of return to schooling. Cross-sectional rates of return are positively related to the unemployment rate in the year the cross-section is taken. The sensitivity of the relationship was not found to be substantially different among the races. (CT)

  5. The Impact of High School Exit Exams on Graduation Rates and Achievement

    Science.gov (United States)

    Caves, Katherine; Balestra, Simone

    2018-01-01

    The authors examined the short- and long-term effects of high school exit exams (HSEEs) on graduation rates and achievement using an interrupted time series approach. There is a positive overall effect of HSEE introduction for graduation rate trends, which is heterogeneous over time. HSEEs have a negative impact on graduation rates in the year of…

  6. Shaping Segregation: Convexity vs. concavity

    NARCIS (Netherlands)

    Gonzalez Briones, Sebastián; Windows-Yule, Kit; Luding, Stefan; Parker, D.J.; Thornton, Anthony Richard

    2014-01-01

    Controlling segregation is both a practical and a theoretical challenge. In this Letter we demonstrate a manner in which rotation-induced segregation may be controlled by altering the geometry of the rotating containers in which granular systems are housed. Using a novel drum design comprising

  7. The Rate of Return to Schooling and the Business Cycle: Additional Estimates.

    Science.gov (United States)

    Kniesner, Thomas J.; And Others

    1980-01-01

    Illustrates that the business cycle does indeed disturb relative Black/White rates of return to schooling. Blacks fare relatively poorly in times of high unemployment. Data tables and formulas are presented to support the argument. (CT)

  8. A Comparison of Satisfaction Ratings of School Psychologists in RTI versus Non-RTI School Districts

    Science.gov (United States)

    Bade-White, Priscilla A.

    2012-01-01

    Teachers' satisfaction with school psychological services has been studied for more than 30 years. Few to no studies, however, are available that provide data about the perceptions of school psychologists regarding their perceived value within different service delivery models, particularly those involving Response to Intervention (RTI) models.…

  9. School quality, economic status and school dropout rates among Mexican teenagers

    Directory of Open Access Journals (Sweden)

    Eunice Danitza Vargas Valle

    2016-01-01

    Full Text Available The aim of this article is to analyze the relationship between dropping out of school and the perceived quality of the last school that Mexican teenagers attended, and examine the interaction between this educational factor and the economic status of this population. Based on the 2010 National Youth Survey, the researchers used the life table to describe this relationship, and Cox regression models to analyze it, including individual, family-related and educational co-variables. The results show that the risk of dropping out of school is indirectly linked to school quality and, to a greater degree, to economic status; and that the gap between students dropping out based on school quality is slightly wider among adolescents of low academic status than among those of high status.

  10. Radiation-induced segregation in Cu-Au alloys

    International Nuclear Information System (INIS)

    Hashimoto, T.; Rehn, L.E.; Okamoto, P.R.

    1987-01-01

    Radiation-induced segregation in a Cu-lat.% Au alloy was investigated using in-situ Rutherford backscattering spectrometry. Irradiation with 1.8-MeV helium produced nonequilibrium gold atom depletion in the near surface region. The amount of segregation was measured as a function of dose, dose rate, and temperature. Segregation was observed in the temperature range between about 300 and 500 0 C. For a calculated dose rate of 3.9 x 10/sup -5/ dpa/s, the radiation-induced segregation rate peaked near 400 0 C. Theoretical analysis based on the Johnson-Lam model predicted that the amount of segregation would be directly proportional to dose at the early stage of irradiation, would deviate from linearity with a continuously decreasing slope of intermediate doses, and finally approach a constant value after high doses. The analysis also predicted that the segregation rate would vary as the - 1/4th power of the dose rate at constant dose in the low temperature region. These predictions were all verified experimentally. A procedure for extracting relative defect production efficiencies from similar measurements is discussed

  11. Wages, Promotions, and Gender Workplace Segregation (Japanese)

    OpenAIRE

    HASHIMOTO Yuki; SATO Kaori

    2014-01-01

    In this paper, we examine how job assignments affect gender pay gap and the promotion rate of female workers using personnel records from a large Japanese manufacturing firm, where newly-hired male and female workers are systematically assigned to different workplaces ("gender job segregation"). According to our gender pay gap analysis, we find that controlling for workplace heterogeneity leads to a larger, rather than smaller, gender pay gap, implying that female workers are sorted into work...

  12. Wages, Promotions, and Gender Workplace Segregation

    OpenAIRE

    橋本, 由紀; 佐藤, 香織

    2014-01-01

    In this paper, we examine how job assignments affect gender pay gap and the promotion rate of female workers using personnel records from a large Japanese manufacturing firm, where newly-hired male and female workers are systematically assigned to different workplaces ("gender job segregation"). According to our gender pay gap analysis, we find that controlling for workplace heterogeneity leads to a larger, rather than smaller, gender pay gap, implying that female workers are sorted into work...

  13. Neighborhood design and rates of walking and biking to elementary school in 34 California communities.

    Science.gov (United States)

    Braza, Mark; Shoemaker, Wendy; Seeley, Anne

    2004-01-01

    This study evaluates the relationship between neighborhood design and rates of students walking and biking to elementary school. Pairwise correlations and multiple regression models were estimated based on a cross-sectional study of elementary schools and their surrounding neighborhoods. Setting and Subjects. Thirty-four (23%) of 150 California public elementary schools holding October 1999 Walk to School Day events participated in the study. Teachers asked fifth-grade students how they arrived to school 1 week before Walk to School Day. 1990 U.S. Census data measured population density and number of intersections per street mile, whereas 1998-1999 California Department of Education data measured school size, the percentage of students receiving public welfare, and the percentage of students of various ethnicities. Population density (p = .000) and school size (p = .053) were significantly associated with walking and biking rates in regression models controlling for number of intersections per street mile, the percentage of students receiving public welfare, and the percentage of students of various ethnicities. The number of intersections per street mile was associated with walking and biking rates in pairwise correlations (p = .003) but not in regression models. The results support the hypothesis that the walking and biking rates are higher in denser neighborhoods and to smaller schools but do not support the hypothesis that rates are higher in neighborhoods with a high number of intersections per street mile. We suggest that detailed data for a larger sample of students would allow statistical models to isolate the effect of specific design characteristics.

  14. Chromosome segregation in plant meiosis

    Directory of Open Access Journals (Sweden)

    Linda eZamariola

    2014-06-01

    Full Text Available Faithful chromosome segregation in meiosis is essential for ploidy stability over sexual life cycles. In plants, defective chromosome segregation caused by gene mutations or other factors leads to the formation of unbalanced or unreduced gametes creating aneuploid or polyploid progeny, respectively. Accurate segregation requires the coordinated execution of conserved processes occurring throughout the two meiotic cell divisions. Synapsis and recombination ensure the establishment of chiasmata that hold homologous chromosomes together allowing their correct segregation in the first meiotic division, which is also tightly regulated by cell-cycle dependent release of cohesin and monopolar attachment of sister kinetochores to microtubules. In meiosis II, bi-orientation of sister kinetochores and proper spindle orientation correctly segregate chromosomes in four haploid cells. Checkpoint mechanisms acting at kinetochores control the accuracy of kinetochore-microtubule attachment, thus ensuring the completion of segregation. Here we review the current knowledge on the processes taking place during chromosome segregation in plant meiosis, focusing on the characterization of the molecular factors involved.

  15. Student Socioeconomic Status and Gender: Impacts on School Counselors' Ratings of Student Personal Characteristics and School Counselors' Self-Efficacy

    Science.gov (United States)

    Glance, Dorea E.

    2012-01-01

    This research focused on how students' socioeconomic status and gender impact school counselors' ratings of student personal characteristics and school counselor self-efficacy. While previous literature focuses on how students' socioeconomic status and gender impact school counselors' ratings of academic characteristics such as…

  16. Surface segregation during irradiation

    International Nuclear Information System (INIS)

    Rehn, L.E.; Lam, N.Q.

    1985-10-01

    Gibbsian adsorption is known to alter the surface composition of many alloys. During irradiation, four additional processes that affect the near-surface alloy composition become operative: preferential sputtering, displacement mixing, radiation-enhanced diffusion and radiation-induced segregation. Because of the mutual competition of these five processes, near-surface compositional changes in an irradiation environment can be extremely complex. Although ion-beam induced surface compositional changes were noted as long as fifty years ago, it is only during the past several years that individual mechanisms have been clearly identified. In this paper, a simple physical description of each of the processes is given, and selected examples of recent important progress are discussed. With the notable exception of preferential sputtering, it is shown that a reasonable qualitative understanding of the relative contributions from the individual processes under various irradiation conditions has been attained. However, considerably more effort will be required before a quantitative, predictive capability can be achieved. 29 refs., 8 figs

  17. Dislocation and void segregation in copper during neutron irradiation

    DEFF Research Database (Denmark)

    Singh, Bachu Narain; Leffers, Torben; Horsewell, Andy

    1986-01-01

    ); the irradiation experiments were carried out at 250 degree C. The irradiated specimens were examined by transmission electron microscopy. At both doses, the irradiation-induced structure was found to be highly segregated; the dislocation loops and segments were present in the form of irregular walls and the voids...... density, the void swelling rate was very high (approximately 2. 5% per dpa). The implications of the segregated distribution of sinks for void formation and growth are briefly discussed....

  18. Should Educators and Parents Encourage Other-Gender Interactions? Gender Segregation and Sexism

    Science.gov (United States)

    Keener, Emily; Mehta, Clare; Strough, JoNell

    2013-01-01

    We investigated gender differences in the association between gender-segregated peer preferences and sexism in adolescents (15-17 years, 60 boys and 85 girls). To assess gender-segregated peer preferences, adolescents nominated peers for interaction in two contexts: "hanging out" at home and working on a school project. The Modern Sexism…

  19. U.S. High School Graduation Rates: Patterns and Explanations. NBER Working Paper No. 18701

    Science.gov (United States)

    Murnane, Richard J.

    2013-01-01

    I survey the evidence on patterns in U.S. high school graduation rates over the period 1970-2010 and report the results of new research conducted to fill in holes in the evidence. I begin by pointing out the strengths and limitations of existing data sources. I then describe six striking patterns in graduation rates. They include stagnation over…

  20. NCLB Implementation Report: State Approaches for Calculating High School Graduation Rates.

    Science.gov (United States)

    Swanson, Christopher B.

    This review investigated the state accountability Workbooks provisionally approved and publicly reported by the U.S. Department of Education (DOE) as of June 2003. These documents were obtained from the DOE Web site. This report examines state definitions of high school graduation rates and strategies for constructing graduation rate indicators. A…

  1. Segregation and Socialization: Academic Segregation and Citizenship Attitudes of Adolescents in Comparative Perspective?

    Directory of Open Access Journals (Sweden)

    Dimokritos Kavadias

    2017-07-01

    Full Text Available Purpose: There is a tendency to assess educational systems in terms of their efficiency in gaining high scores on cognitive skills. Schools perform, however, also a socializing function. The whole policy debate tends to ignore the impact of educational systems on attitudes or democratic values. This contribution focuses on the impact of the organization of education in European societies on the civic attitudes of adolescents. Design/methodology/approach: We explore the impact of academic segregation – the practice of segregating children on the basis of their scholastic achievement – on attitudes of adolescents living in different educational systems. We use the International Civic and Citizenship Education Study (2009 relying on multilevel models. Findings: Pupils differ in their outlook on fellow citizens, according to the ways in which educational systems select and differentiate throughout school careers. More specifically, there is a negative impact of academic segregation on the attitudes towards immigrants and ethnic minorities. Research limitations/implications: The experience of adolescents based on their educational achievement seems to affect how they perceive other people. We have not answered the question why this is the case. We hope to have provided a minimal indication of the impact of inequality on social outcomes.

  2. Applied thermodynamics: Grain boundary segregation

    Czech Academy of Sciences Publication Activity Database

    Lejček, Pavel; Zheng, L.; Hofmann, S.; Šob, Mojmír

    2014-01-01

    Roč. 16, č. 3 (2014), s. 1462-1484 ISSN 1099-4300 R&D Projects: GA ČR(CZ) GAP108/12/0311; GA ČR GAP108/12/0144; GA MŠk(CZ) ED1.1.00/02.0068 Institutional support: RVO:68378271 ; RVO:68081723 Keywords : interfacial segregation * Gibbs energy of segregation * enthalpy * entropy * volume * grain boundaries * iron Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.502, year: 2014

  3. PICH promotes mitotic chromosome segregation

    DEFF Research Database (Denmark)

    Nielsen, Christian Thomas Friberg; Hickson, Ian D

    2016-01-01

    PICH is an SNF2-family DNA translocase that appears to play a role specifically in mitosis. Characterization of PICH in human cells led to the initial discovery of "ultra-fine DNA bridges" (UFBs) that connect the 2 segregating DNA masses in the anaphase of mitosis. These bridge structures, which...... further the role of PICH in the timely segregation of the rDNA locus....

  4. Habitat segregation in fish assemblages

    OpenAIRE

    Ibbotson, A.T.

    1990-01-01

    The segregation of habitats of fish assemblages found in the chalk streams and rivers within the Wessex, South West and Southern Water Authority boundaries in southern England have been examined. Habitat segregation is the most frequent type of resource partitioning in natural communities. The habitat of individual fish species will be defined in order to determine the following: (1) the requirements of each species in terms of depth, current velocity, substrate, cover etc.; (2) identify the ...

  5. A Peer-Led High School Transition Program Increases Graduation Rates Among Latino Males.

    Science.gov (United States)

    Johnson, Valerie L; Simon, Patricia; Mun, Eun-Young

    2014-01-01

    The present study investigated the impact of a manualized high school transition program, the Peer Group Connection (PGC) program, on the graduation rate at a low-income, Mid-Atlantic high school. The program utilized twelfth grade student peer leaders to create a supportive environment for incoming ninth grade students. Results of a randomized control trial demonstrated that male students who participated in the program during ninth grade were significantly more likely to graduate from high school within four years than male students in the control group (81% versus 63%). Findings suggest that peers can be effective in delivering a school-based, social emotional learning intervention and that it is possible to intervene in the ninth grade to influence the probability of high school graduation.

  6. Sickness absenteeism rate in Iranian schools during the 2009 epidemic of type a influenza.

    Science.gov (United States)

    Pourabbasi, Ata; Shirvani, Mahbubeh Ebrahimnegad; Khashayar, Patricia

    2012-02-01

    Influenza pandemic was a global event in 2009 and intraschool transmission was its main spread method. The present study was designed to evaluate the absenteeism rate during the type A influenza epidemic. Four hundred and eight students from both a guidance school and high school in the Iranian capital were recruited in this retrospective study. The number of days of absenteeism, since the beginning of the school year until the end of the epidemic was recorded. Two hundred and thirteen students missed school during the disease epidemic because of related causes. In other words, 581 person day absences were reported during this period. The influenza pandemic has led to an increase in the absenteeism rate and may negatively affect the academic performance of the students. Teaching precautionary measures is an effective tool in reducing the number of days of sickness.

  7. Oregon's On-Time High School Graduation Rate Shows Strong Growth in 2014-15. Research Brief

    Science.gov (United States)

    Oregon Department of Education, 2016

    2016-01-01

    Oregon continues to make gains in its on-time high school graduation rate. The rate increased to 74% for the 2014-15 school year--up from 72% the year before. The graduation rate for almost all student groups rose, led by Hispanic students (2.4 percentage points) and Black students (2.4 percentage points). The rate for economically disadvantaged…

  8. Increasing the admission rate to secondary school: The case of primary school student career guidance

    DEFF Research Database (Denmark)

    Høst, Anders; Jensen, Vibeke Myrup; Nielsen, Lisbeth Palmhøj

    Although several studies investigate the effects of school resources on student performance, these studies tend to focus more on intervention effect sizes than on their cost-effectiveness. Exploiting policy-induced variation in Denmark and using high-quality administrative data, we investigate...

  9. DECREASING SCHOOL DROPOUT RATE AS A FACTOR OF ECONOMIC GROWTH AND SOCIAL EMPOWERMENT. THEORETICAL INSIGHTS

    Directory of Open Access Journals (Sweden)

    Alina Badulescu

    2016-07-01

    Full Text Available Economic development and social empowerment in Romania are unconcievable in the absence of a modern education system, which needs both economic and financial investments and social, political, cultural measures to increase the inclusion of young people in school system. In this particular context, given that Romania faces a high degree rate of school dropout, and moreover there are few chances that Romania reach its goals, we try in this paper to look inside the real situation. Indeed, school dropout present serious negative consequences both on individual level and for the whole society. Recognising this fact, next step is to investigate and reveal the determining factors for this situation, and we are particularly interested in the economic and systemic factors. Consequently, we present in this paper first a brief literature review on the fenomenon of school dropping out, including reviewing main studies related to factors, effects, causes etc. In the second part, starting from several statistical data provided by INS, EUROSTAT and UNICEF studies, we propose some theoretical models and policy reccomendations in order to decrease the school dropout rate and especially the early school dropout rate.

  10. Student-teacher relationships matter for school inclusion: school belonging, disability, and school transitions.

    Science.gov (United States)

    Crouch, Ronald; Keys, Christopher B; McMahon, Susan D

    2014-01-01

    For students with disabilities, the process of school inclusion often begins with a move from segregated settings into general education classrooms. School transitions can be stressful as students adjust to a new environment. This study examines the adjustment of 133 students with and without disabilities who moved from a school that served primarily students with disabilities into 23 public schools in a large urban school district in the Midwest. These students and 111 of their teachers and other school staff rated the degree that students felt they belonged in their new schools and the quality of their social interactions. Results show that students who experienced more positive and fewer negative social interactions with school staff had higher school belonging. Teachers accurately noted whether students felt they belonged in their new settings, but were not consistently able to identify student perceptions of negative social interactions with staff. Implications for inclusion and improving our educational system are explored.

  11. Oppositional Defiant Disorder: prevalence based on parent and teacher ratings of Malaysian primary school children.

    Science.gov (United States)

    Gomez, Rapson; Hafetz, Nina; Gomez, Rashika Miranjani

    2013-08-01

    This study examined the prevalence rate of Oppositional Defiant Disorder (ODD) in Malaysian primary school children. In all 934 Malaysian parents and teachers completed ratings of their children using a scale comprising DSM-IV-TR ODD symptoms. Results showed rates of 3.10%, 3.85%, 7.49% and 0.64% for parent, teacher, parent or teacher ("or-rule"), and parent and teacher ("and-rule") ratings, respectively. When the functional impairment criterion was not considered, the rate reported by parents was higher at 13.28%. The theoretical, diagnostic and cultural implications of the findings are discussed. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. Egg positive rate of Enterobius vermicularis of primary school children in Geoje island

    Science.gov (United States)

    Kim, Bong Jin; Lee, Bo Young; Chung, Hyun Kee; Lee, Young Sun; Lee, Kun Hee; Chung, Hae Jin

    2003-01-01

    The status of pinworm (Enterobius vermicularis) egg positive rate of primary school children in Geoje island was investigated by using adhesive cellotape anal swap method, in September, 2002. Total egg positive rates of E. vermicularis were 9.8% (74/754) and those of male and female were 10.8% and 8.7%, respectively. Among three schools examined, Myeongsa primary school showed the highest egg positive rate (12.6%) followed by Yeoncho [9.8% (26/266)] and Geoje [9.1% (35/385)]. As for the age groups, the 2nd grade had the highest egg positive rate (15.3%), whereas the 5th grade showed the lowest egg positive rate (2.6%). The above result led us to confirm that the egg positive rates of E. vermicularis in primary school children in Geoje island were not significantly different from the those in the whole country including urban and rural areas, showing more than 10%. PMID:12666734

  13. Differences in Primary School Students’ Ratings about Themselves and the School

    Directory of Open Access Journals (Sweden)

    Anita Habók

    2014-10-01

    Full Text Available L2L is a frequently used concept, which can be approached from different perspectives. In our theoretical background we provide an overview of the early and current research trends, then we approach the issue from the perspective of the Finnish framework, the second order learning and the learning how to learn approaches. Next, we present the results of the ’Me and the school’ questionnaire from the Finnish framework. Our participants were 5th and 6th grade primary school students. We found that this online questionnaire is a reliable tool for the Hungarian sample. Comparing the results of Grades 5 and 6, we did not register significant relationships between the grades, except for their ‘use of computer’. The most important differences were discovered between the genders, where significantly higher mean values were observed for girls. We also analysed the effects of mathematics and literature school results on some variables. It can be concluded that school results have a significant effect on students’ performance and attitude. While the effect of attitudes on students’ performance was not substantial, there was a stronger effect on students’ evaluation of own competencies in maths for both genders and in reading for boys.

  14. Study on segregation of aluminium-uranium alloys

    International Nuclear Information System (INIS)

    Lima, Rui Marques de

    1979-01-01

    The relations between alloy solidification and solute segregation were considered. The solidification structure and the solute redistribution during the solidification of alloys with dendritic micro morphology were studied. The macro and micro segregation theories were reviewed. The mechanisms that could change the solidification structure were taken into account in the context of more homogeneous alloy production. Aluminum alloys solidification structures and segregation were studied experimentally in the 13 to 45% uranium range, usually considering solidification in static molds. The uranium alloys with up to 20% uranium were studied both for solidification in ingot molds and for controlled directional solidification. It was verified that these alloy compositions had structures similar to those of hipoeutectic alloys, showing an a phase with dendritic morphology and inter dendritic eutectic. For the alloys with more than 25% uranium, it was observed the formation of UAl 3 and UAl 4 phases with dendritic morphology. The dendritic UAl 3 , phase morphology was affected both by the solute concentration in the alloy and by the growth rate. The dendritic UAl 3 phase non-singular aspect could be destroyed with decrease of the alloy solute concentration. In the alloys obtained with higher cooling rates it was found a tendency for the formation of substantial quantities of equi axial crystals of the solute enriched phases in the central regions of the ingot upper half. In the more external regions it was observed dendritic growth of these phases, for alloy compositions with over 25% uranium. An adequate reduction in the cooling rate changed the solidification structure form and distribution, as well as the segregation type and intensity. The uranium content in the solidified macro structures is presented as a function of: cooling rate, superheating, mold size, mold form and its temperature, number of remelting and time for the melt homogenization and agitation. It was

  15. Trends in Personal Belief Exemption Rates Among Alternative Private Schools: Waldorf, Montessori, and Holistic Kindergartens in California, 2000–2014

    Science.gov (United States)

    Bednarczyk, Robert A.; Richards, Jennifer L.; Allen, Kristen E.; Warraich, Gohar J.; Omer, Saad B.

    2017-01-01

    Objectives. To evaluate trends in rates of personal belief exemptions (PBEs) to immunization requirements for private kindergartens in California that practice alternative educational methods. Methods. We used California Department of Public Health data on kindergarten PBE rates from 2000 to 2014 to compare annual average increases in PBE rates between schools. Results. Alternative schools had an average PBE rate of 8.7%, compared with 2.1% among public schools. Waldorf schools had the highest average PBE rate of 45.1%, which was 19 times higher than in public schools (incidence rate ratio = 19.1; 95% confidence interval = 16.4, 22.2). Montessori and holistic schools had the highest average annual increases in PBE rates, slightly higher than Waldorf schools (Montessori: 8.8%; holistic: 7.1%; Waldorf: 3.6%). Conclusions. Waldorf schools had exceptionally high average PBE rates, and Montessori and holistic schools had higher annual increases in PBE rates. Children in these schools may be at higher risk for spreading vaccine-preventable diseases if trends are not reversed. PMID:27854520

  16. Trends in Personal Belief Exemption Rates Among Alternative Private Schools: Waldorf, Montessori, and Holistic Kindergartens in California, 2000-2014.

    Science.gov (United States)

    Brennan, Julia M; Bednarczyk, Robert A; Richards, Jennifer L; Allen, Kristen E; Warraich, Gohar J; Omer, Saad B

    2017-01-01

    To evaluate trends in rates of personal belief exemptions (PBEs) to immunization requirements for private kindergartens in California that practice alternative educational methods. We used California Department of Public Health data on kindergarten PBE rates from 2000 to 2014 to compare annual average increases in PBE rates between schools. Alternative schools had an average PBE rate of 8.7%, compared with 2.1% among public schools. Waldorf schools had the highest average PBE rate of 45.1%, which was 19 times higher than in public schools (incidence rate ratio = 19.1; 95% confidence interval = 16.4, 22.2). Montessori and holistic schools had the highest average annual increases in PBE rates, slightly higher than Waldorf schools (Montessori: 8.8%; holistic: 7.1%; Waldorf: 3.6%). Waldorf schools had exceptionally high average PBE rates, and Montessori and holistic schools had higher annual increases in PBE rates. Children in these schools may be at higher risk for spreading vaccine-preventable diseases if trends are not reversed.

  17. Image segregation in strabismic amblyopia.

    Science.gov (United States)

    Levi, Dennis M

    2007-06-01

    Humans with naturally occurring amblyopia show deficits thought to involve mechanisms downstream of V1. These include excessive crowding, abnormal global image processing, spatial sampling and symmetry detection and undercounting. Several recent studies suggest that humans with naturally occurring amblyopia show deficits in global image segregation. The current experiments were designed to study figure-ground segregation in amblyopic observers with documented deficits in crowding, symmetry detection, spatial sampling and counting, using similar stimuli. Observers had to discriminate the orientation of a figure (an "E"-like pattern made up of 17 horizontal Gabor patches), embedded in a 7x7 array of Gabor patches. When the 32 "background" patches are vertical, the "E" pops-out, due to segregation by orientation and performance is perfect; however, if the background patches are all, or mostly horizontal, the "E" is camouflaged, and performance is random. Using a method of constant stimuli, we varied the number of "background" patches that were vertical and measured the probability of correct discrimination of the global orientation of the E (up/down/left/right). Surprisingly, amblyopes who showed strong crowding and deficits in symmetry detection and counting, perform normally or very nearly so in this segregation task. I therefore conclude that these deficits are not a consequence of abnormal segregation of figure from background.

  18. Energy and IAQ Implications of Alternative Minimum Ventilation Rates in California Retail and School Buildings

    Energy Technology Data Exchange (ETDEWEB)

    Dutton, Spencer M. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Fisk, William J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2015-01-01

    For a stand-alone retail building, a primary school, and a secondary school in each of the 16 California climate zones, the EnergyPlus building energy simulation model was used to estimate how minimum mechanical ventilation rates (VRs) affect energy use and indoor air concentrations of an indoor-generated contaminant. The modeling indicates large changes in heating energy use, but only moderate changes in total building energy use, as minimum VRs in the retail building are changed. For example, predicted state-wide heating energy consumption in the retail building decreases by more than 50% and total building energy consumption decreases by approximately 10% as the minimum VR decreases from the Title 24 requirement to no mechanical ventilation. The primary and secondary schools have notably higher internal heat gains than in the retail building models, resulting in significantly reduced demand for heating. The school heating energy use was correspondingly less sensitive to changes in the minimum VR. The modeling indicates that minimum VRs influence HVAC energy and total energy use in schools by only a few percent. For both the retail building and the school buildings, minimum VRs substantially affected the predicted annual-average indoor concentrations of an indoor generated contaminant, with larger effects in schools. The shape of the curves relating contaminant concentrations with VRs illustrate the importance of avoiding particularly low VRs.

  19. An Analysis of the Relationship between Implementation of School-Wide Positive Behavior Interventions and Supports and High School Dropout Rates

    Science.gov (United States)

    Freeman, Jennifer; Simonsen, Brandi; McCoach, D. Betsy; Sugai, George; Lombardi, Allison; Horner, Rob

    2015-01-01

    The purpose of this study was to explore the direct and indirect effects of SWPBIS on high school dropout rates. We used structural equation modeling methods to analyze the web of relationships among important high school level outcomes and SWPBIS in a large sample of high schools from 37 states. Results suggest that SWPBIS has statistically…

  20. Nasal congestion in relation to low air exchange rate in schools. Evaluation by acoustic rhinometry.

    Science.gov (United States)

    Wålinder, R; Norbäck, D; Wieslander, G; Smedje, G; Erwall, C

    1997-09-01

    Upper airway symptoms are common, but there is little information available on clinical findings in relation to indoor air pollution. This pilot study was conducted to test whether increased levels of indoor air pollutants in schools may correlate to a swelling of the nasal mucosa. The assumption was made that the degree of swelling could be related to the degree of decongestive effect of xylometazoline, and measured by acoustic rhinometry. The study was performed among 15 subjects in a school with low air exchange rate (0.6 air changes/h) and 12 subjects in a school with high air exchange rate (5.2 air changes/h). Hygienic measurements were performed in both schools. Acoustic rhinometry was performed for each individual under standardized forms. Cross-sectional areas and volumes of the nasal cavity were measured before and after decongestion with xylometazoline hydrochloride. Absolute values of the minimal cross-sectional area were lower in the school with poor ventilation. The decongestive effect of xylometazoline was significantly higher in the school with low air exchange, when correction for the influence of age was made. A diminished decongestive effect was seen with increasing age. The exposure measurements showed that indoor concentrations of volatile organic compounds, bacteria and moulds were higher in the school with low ventilation. In conclusion, raised levels of indoor air pollutants due to inadequate ventilation in schools may affect the upper airways and cause a swelling of the nasal mucosa, and acoustic rhinometry could be a useful objective method to measure human nasal reactions to the indoor environment.

  1. Selective mobility, segregation and neighbourhood effects

    Directory of Open Access Journals (Sweden)

    Sanne Boschman

    2015-11-01

    residential satisfaction (Galster and Hesser, 1981. If certain neighbourhood characteristics lead to dissatisfaction and therefore to mobility desires for specific groups, this might lead to selective mobility and segregation. Therefore, in Chapter 2 I study individual differences in the determinants of residential satisfaction.  I estimate ordered logit models explaining satisfaction on residents of urban areas within the Housing Research Netherlands 2012 survey. To test whether there are individual differences in the effects of neighbourhood characteristics on satisfaction I include interaction effects between individual characteristics and neighbourhood characteristics. These interaction effects test whether neighbourhood characteristics such as the neighbourhood ethnic composition, crime rates or dwelling values have similar effects on all individuals, or whether individual characteristics affect the size and direction of these effects. To my knowledge, previously only Greif (2015 and Parkes et al. (2002 have tested interaction effects between tenure and neighbourhood characteristics and there is no earlier research on ethnic or household differences in the determinants of neighbourhood satisfaction. Because there is almost no earlier research on individual differences in the determinants of satisfaction, I combine literature on residential satisfaction with literature on residential preferences, mobility desires and behaviour to create hypotheses about which neighbourhood characteristics are important to whom. In line with the literature, I find that the share of non-western minorities in the neighbourhood has a negative effect on neighbourhood satisfaction, an effect that is stronger for natives than for non-western minorities themselves. This can be explained by own group preferences; people are more satisfied in neighbourhoods with higher shares of their own ethnic group and when this is taken into account the differences between ethnic groups in the effect of the

  2. The relationship of high school graduation exams to graduation rates and SAT scores.

    OpenAIRE

    Gregory J. Marchant; Sharon E. Paulson

    2005-01-01

    The current study examined the effect of high school graduation exams on states' graduation rates, states' aggregated SAT scores, and individual students' SAT scores. Three data sources were used: One source identified states requiring a standardized test for graduation; the NCES provided state aggregated data on graduation rates for the class of 2002; and the College Board provided its 2001 SAT database for all test-takers. After controlling for students' demographic characteristics (e.g., r...

  3. Segregation in a Galton Board

    International Nuclear Information System (INIS)

    Benito, J G; Vidales, A M; Ippolito, I

    2009-01-01

    This work deals with a numerical study of the problem of separation of particles with different elastic properties. The separation procedure uses a Galton Board which consist in a bidimensional system of obstacles arranged in a triangular lattice. Disks of equal diameters but different elastic properties are launched from the top of the device. The Galton Board is commonly used for mixing particles, but here, we intend to find special conditions under which one can use it as a segregating device. We introduce a mixture of particles and generate, through simulations, different conditions to favor the segregation process based on the different elastic coefficients of the particles. We inspect which is the best configuration of size, density of obstacles and wall separation to favor the separations of particles. Our results prove that the Galton Board can be used as a segregation device under certain conditions.

  4. Education and the Economy: Boosting New Jersey's Economy by Improving High School Graduation Rates

    Science.gov (United States)

    Alliance for Excellent Education, 2011

    2011-01-01

    Building on its previous work examining education and the economy, the Alliance for Excellent Education (the Alliance), with generous support from State Farm[R], analyzed the economies of all fifty states and the District of Columbia to determine the economic benefits that states could see by improving high school graduation rates. Using a…

  5. Education and the Economy: Boosting New Hampshire's Economy by Improving High School Graduation Rates

    Science.gov (United States)

    Alliance for Excellent Education, 2011

    2011-01-01

    Building on its previous work examining education and the economy, the Alliance for Excellent Education (the Alliance), with generous support from State Farm[R], analyzed the economies of all fifty states and the District of Columbia to determine the economic benefits that states could see by improving high school graduation rates. Using a…

  6. Education and the Economy: Boosting New Mexico's Economy by Improving High School Graduation Rates

    Science.gov (United States)

    Alliance for Excellent Education, 2011

    2011-01-01

    Building on its previous work examining education and the economy, the Alliance for Excellent Education (the Alliance), with generous support from State Farm[R], analyzed the economies of all fifty states and the District of Columbia to determine the economic benefits that states could see by improving high school graduation rates. Using a…

  7. Education and the Economy: Boosting New York's Economy by Improving High School Graduation Rates

    Science.gov (United States)

    Alliance for Excellent Education, 2011

    2011-01-01

    Building on its previous work examining education and the economy, the Alliance for Excellent Education (the Alliance), with generous support from State Farm[R], analyzed the economies of all fifty states and the District of Columbia to determine the economic benefits that states could see by improving high school graduation rates. Using a…

  8. Residential Property Composition of School Districts: Its Effect on Tax Rate and Per Pupil Revenue.

    Science.gov (United States)

    Lundeen, Virginia; And Others

    This study related tax rate and per pupil revenue to residential assessed valuation, percent residential of total assessed valuation, and selected socioeconomic independent variables for school districts in Cook, DeKalb, DuPage, Kane, and Lake counties in Illinois. Findings suggest that for homeowners and the students of these counties in 1976,…

  9. National- and State-Level High School Graduation Rates for English Learners. Fast Facts

    Science.gov (United States)

    Office of English Language Acquisition, US Department of Education, 2016

    2016-01-01

    The Office of English Language Acquisition (OELA) has synthesized key data on English learners (ELs) into two-page PDF sheets, by topic, with graphics, plus key contacts. The topic for this report on English Learners (ELs) are national- and state-level high school graduation rates for English Learners. The following data are presented: (1)…

  10. The Impact of School Socioeconomic Status on Student-Generated Teacher Ratings

    Science.gov (United States)

    Agnew, Steve

    2011-01-01

    This paper uses ordinary least squares, logit and probit regressions, along with chi-square analysis applied to nationwide data from the New Zealand ratemyteacher website to establish if there is any correlation between student ratings of their teachers and the socioeconomic status of the school the students attend. The results show that students…

  11. Substance Use among Middle School Students: Associations with Self-Rated and Peer-Nominated Popularity

    Science.gov (United States)

    Tucker, Joan S.; Green, Harold D., Jr.; Zhou, Annie J.; Miles, Jeremy N. V.; Shih, Regina A.; D'Amico, Elizabeth J.

    2011-01-01

    Associations of popularity with adolescent substance use were examined among 1793 6-8th grade students who completed an in-school survey. Popularity was assessed through both self-ratings and peer nominations. Students who scored higher on either measure of popularity were more likely to be lifetime cigarette smokers, drinkers, and marijuana…

  12. The Use of Gap Analysis to Increase Student Completion Rates at Travelor Adult School

    Science.gov (United States)

    Gil, Blanca Estela

    2013-01-01

    This project applied the gap analysis problem-solving framework (Clark & Estes, 2008) in order to help develop strategies to increase completion rates at Travelor Adult School. The purpose of the study was to identify whether the knowledge, motivation and organization barriers were contributing to the identified gap. A mixed method approached…

  13. The High Cost of Low Graduation Rates in North Carolina. School Choice Issues in the State

    Science.gov (United States)

    Gottlob, Brian J.

    2007-01-01

    North Carolina has a dropout crisis--only two thirds of North Carolina high school students graduate. One reason this crisis has not received the attention it deserves is because the state was reporting badly inflated graduation rates (supposedly as high as 97 percent) until it finally adopted a more realistic reporting method earlier this year.…

  14. Grain Boundary Segregation in Metals

    CERN Document Server

    Lejcek, Pavel

    2010-01-01

    Grain boundaries are important structural components of polycrystalline materials used in the vast majority of technical applications. Because grain boundaries form a continuous network throughout such materials, their properties may limit their practical use. One of the serious phenomena which evoke these limitations is the grain boundary segregation of impurities. It results in the loss of grain boundary cohesion and consequently, in brittle fracture of the materials. The current book deals with fundamentals of grain boundary segregation in metallic materials and its relationship to the grain boundary structure, classification and other materials properties.

  15. "Suited to Their Needs": White Innocence as a Vestige of Segregation

    Science.gov (United States)

    Orozco, Richard; Jaime Diaz, Jesus

    2016-01-01

    Discourses that supported de jure segregated schools often invoked White innocence in the form of altruistic motivations. These same invocations are found in more contemporary school policy discourses. The authors of this article argue, based on the concept of intertextuality of discourse, the existence of contemporary schooling policies as…

  16. Biculturalism and Segregated Schooling in Hong Kong

    Science.gov (United States)

    Fang, Gao; Chun, Lai

    2018-01-01

    The literature on acculturation illustrates that a bulk of non-dominant ethnocultural minorities consider themselves bicultural, involving both dominant and ethnic cultures. Yet, little is known about how bicultural individuals perceive and construct dual cultures, and how their two cultural identities are played out in daily interactions. While…

  17. School burnout and heart rate variability: risk of cardiovascular disease and hypertension in young adult females.

    Science.gov (United States)

    May, Ross W; Seibert, Gregory S; Sanchez-Gonzalez, Marcos A; Fincham, Frank D

    2018-05-01

    Emerging research documents the relationship between school burnout and some indicators of increased cardiovascular risk. Indicators of cardiovascular functioning assessed via ambulatory blood pressure and heart rate variability (HRV) have not been thoroughly explored in this research domain. Therefore, the current study examined relationships between school burnout and indicators of cardiac functioning via 24 h ambulatory blood pressure (BP) and electrocardiogram monitoring in a sample of young adult female undergraduates (N = 88). Two hypotheses were tested: (1) that independent of related negative affective symptomology (depression and anxiety), increased school burnout would be related to greater systolic and diastolic BP, higher low frequency (LF) HRV and lower very low frequency (VLF) HRV, and (2) that lower VLF would be related to greater school burnout independently of LF HRV. Hierarchical multiple regression analyzes showed that school burnout was significantly related to elevated ambulatory BP (systolic and diastolic) and HRV markers of increased cardiac sympathovagal tone. These findings support the hypotheses and suggest that school burnout might be implicated in the development of pre-hypertension or early cardiovascular disease. Study limitations and the need for future longitudinal research are discussed.

  18. The relationship of high school graduation exams to graduation rates and SAT scores.

    Directory of Open Access Journals (Sweden)

    Gregory J. Marchant

    2005-01-01

    Full Text Available The current study examined the effect of high school graduation exams on states' graduation rates, states' aggregated SAT scores, and individual students' SAT scores. Three data sources were used: One source identified states requiring a standardized test for graduation; the NCES provided state aggregated data on graduation rates for the class of 2002; and the College Board provided its 2001 SAT database for all test-takers. After controlling for students' demographic characteristics (e.g., race, family education and income, GPA and class rank, regression analyses revealed that states requiring graduation exams had lower graduation rates and lower SAT scores. Individually, students from states requiring a graduation exam performed more poorly on the SAT than did students from states not requiring an exam. The impact of high stakes tests' on students' motivation to stay in school and on the teaching of critical thinking skills (tested by the SAT are discussed.

  19. Direct behavior rating as a school-based behavior screener for elementary and middle grades.

    Science.gov (United States)

    Chafouleas, Sandra M; Kilgus, Stephen P; Jaffery, Rose; Riley-Tillman, T Chris; Welsh, Megan; Christ, Theodore J

    2013-06-01

    The purpose of this study was to investigate how Direct Behavior Rating Single Item Scales (DBR-SIS) involving targets of academically engaged, disruptive, and respectful behaviors function in school-based screening assessment. Participants included 831 students in kindergarten through eighth grades who attended schools in the northeastern United States. Teachers provided behavior ratings for a sample of students in their classrooms on the DBR-SIS, the Behavioral and Emotional Screening System (Kamphaus & Reynolds, 2007), and the Student Risk Screening Scale (Drummond, 1994). Given variations in rating procedures to accommodate scheduling differences across grades, analysis was conducted separately for elementary school and middle school grade levels. Results suggested that the recommended cut scores, the combination of behavior targets, and the resulting conditional probability indices varied depending on grade level grouping (lower elementary, upper elementary, middle). For example, for the lower elementary grade level grouping, a combination of disruptive behavior (cut score=2) and academically engaged behavior (cut score=8) was considered to offer the best balance among indices of diagnostic accuracy, whereas a cut score of 1 for disruptive behavior and 8 for academically engaged behavior were recommended for the upper elementary school grade level grouping and cut scores of 1 and 9, respectively, were suggested for middle school grade level grouping. Generally, DBR-SIS cut scores considered optimal for screening using single or combined targets including academically engaged behavior and disruptive behavior by offering a reasonable balance of indices for sensitivity (.51-.90), specificity (.47-.83), negative predictive power (.94-.98), and positive predictive power (.14-.41). The single target of respectful behavior performed poorly across all grade level groups, and performance of DBR-SIS targets was relatively better in the elementary school than middle

  20. Interrater Reliability of the ENERGY Photo-Rating Instrument for School Environments Related to Physical Activity and Eating

    NARCIS (Netherlands)

    Altenburg, T.; te Velde, S.; Chiu, K.-J.; Moschonis, G.; Manios, Y.; De Bourdeaudhuij, I.; Vik, F.N.; Lien, N.; Brug, J.; Chinapaw, M.

    Background: The school environment can play an important role in the prevention of childhood overweight and obesity. Photos of the school environment may contribute to more adequate measurement of the school environment, as photos can be rated by different assessors. We aimed to examine the

  1. The residential segregation patterns of whites by socioeconomic status, 2000-2011.

    Science.gov (United States)

    Sharp, Gregory; Iceland, John

    2013-07-01

    In light of increasing racial and ethnic diversity, a recent housing crisis, and deep economic recession, arguments pertaining to the role of socioeconomic status (SES) in shaping patterns of racial/ethnic segregation remain salient. Using data from the 2000 decennial census and the 2007-2011 American Community Survey, we provide new evidence on the residential segregation patterns of whites from minorities by SES (income, education, and poverty). Results from our comprehensive analyses indicate that SES matters for the segregation patterns of whites from minorities. In particular, we find that whites as a whole are less segregated from higher-SES minority group members than lower-SES ones. Among whites, those of higher SES are more segregated from blacks and Hispanics as a whole and less segregated from Asians, indicating the importance of SES differentials across racial/ethnic groups in shaping residential patterns. We also find that during the 2000s, white-black segregation remained stable or declined, while whites became more segregated from Hispanics and Asians by all SES indicators. Fixed-effects models indicate that increasing white-minority SES segregation was fueled in part by increases in a metropolitan area's immigrant and elderly populations, minority poverty rate, and home values, while declining segregation was associated with rising education levels and new housing construction. Copyright © 2013 Elsevier Inc. All rights reserved.

  2. The residential segregation patterns of whites by socioeconomic status, 2000–2011

    Science.gov (United States)

    Sharp, Gregory; Iceland, John

    2013-01-01

    In light of increasing racial and ethnic diversity, a recent housing crisis, and deep economic recession, arguments pertaining to the role of socioeconomic status (SES) in shaping patterns of racial/ethnic segregation remain salient. Using data from the 2000 decennial census and the 2007–2011 American Community Survey, we provide new evidence on the residential segregation patterns of whites from minorities by SES (income, education, and poverty). Results from our comprehensive analyses indicate that SES matters for the segregation patterns of whites from minorities. In particular, we find that whites as a whole are less segregated from higher-SES minority group members than lower-SES ones. Among whites, those of higher SES are more segregated from blacks and Hispanics as a whole and less segregated from Asians, indicating the importance of SES differentials across racial/ethnic groups in shaping residential patterns. We also find that during the 2000s, white-black segregation remained stable or declined, while whites became more segregated from Hispanics and Asians by all SES indicators. Fixed-effects models indicate that increasing white-minority SES segregation was fueled in part by increases in a metropolitan area’s immigrant and elderly populations, minority poverty rate, and home values, while declining segregation was associated with rising education levels and new housing construction. PMID:23721673

  3. Sexual orientation, prejudice and segregation

    NARCIS (Netherlands)

    Plug, E.; Webbink, D.; Martin, N.

    2014-01-01

    This article examines whether gay and lesbian workers sort into tolerant occupations. With information on sexual orientation, prejudice, and occupational choice taken from Australian Twin Registers, we find that gays and lesbians shy away from prejudiced occupations. We show that our segregation

  4. Radiation-induced segregation in binary and ternary alloys

    International Nuclear Information System (INIS)

    Okamoto, P.R.; Rehn, L.E.

    1979-01-01

    A review is given of our current knowledge of radiation-induced segregation of major and minor elements in simple binary and ternary alloys as derived from experimental techniques such as Auger electron spectroscopy, secondary-ion mass spectroscopy, ion-backscattering, infrared emissivity measurements and transmission electron microscopy. Measurements of the temperature, dose and dose-rate dependences as well as of the effects of such materials variables as solute solubility, solute misfit and initial solute concentration has proved particularly valuable in understanding the mechanisms of segregation. The interpretation of these data in terms of current theoretical models which link solute segregation behavior to defect-solute binding interactions and/or to the relative diffusion rates of solute and solvent atoms the interstitial and vacancy migration mechanisms has, in general, been fairly successful and has provided considerable insight into the highly interrelated phenomena of solute-defect trapping, solute segregation, phase stability and void swelling. Specific examples in selected fcc, bcc and hcp alloy systems are discussed with particular emphasis given to the effects of radiation-induced segregation on the phase stability of single-phase and two-phase binary alloys and simple Fe-Cr-Ni alloys. (Auth.)

  5. Heider balance, asymmetric ties, and gender segregation

    Science.gov (United States)

    Krawczyk, Małgorzata J.; del Castillo-Mussot, Marcelo; Hernández-Ramírez, Eric; Naumis, Gerardo G.; Kułakowski, Krzysztof

    2015-12-01

    To remove a cognitive dissonance in interpersonal relations, people tend to divide their acquaintances into friendly and hostile parts, both groups internally friendly and mutually hostile. This process is modeled as an evolution toward the Heider balance. A set of differential equations have been proposed and validated (Kułakowski et al., 2005) to model the Heider dynamics of this social and psychological process. Here we generalize the model by including the initial asymmetry of the interpersonal relations and the direct reciprocity effect which removes this asymmetry. Our model is applied to the data on enmity and friendship in 37 school classes and 4 groups of teachers in México. For each class, a stable balanced partition is obtained into two groups. The gender structure of the groups reveals stronger gender segregation in younger classes, i.e. of age below 12 years, a fact consistent with other general empirical results.

  6. Microstructural characterization and formation mechanism of abnormal segregation band of hot rolled ferrite/pearlite steel

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Rui [School of Materials Science and Engineering, Shandong University, Jinan 250061 (China); Engineering Research Center of Large Size Alloy Structural Steel Bars of Shandong Province, Jinan 250061 (China); School of Materials Science and Engineering, Shandong University of Technology, Zibo 255049 (China); Li, Shengli, E-mail: lishengli@sdu.edu.cn [School of Materials Science and Engineering, Shandong University, Jinan 250061 (China); Engineering Research Center of Large Size Alloy Structural Steel Bars of Shandong Province, Jinan 250061 (China); Zhu, Xinde [School of Materials Science and Engineering, Shandong University, Jinan 250061 (China); Ao, Qing [School of Materials Science and Engineering, Shandong University, Jinan 250061 (China); Engineering Research Center of Large Size Alloy Structural Steel Bars of Shandong Province, Jinan 250061 (China)

    2015-10-15

    In order to further reveal the microstructural characterization and formation mechanism of abnormal segregation band of hot rolled ferrite/pearlite steel, the microstructure of this type steel was intensively studied with Scanning Auger Microprobe (SAM), etc. The results show that severe C–Mn segregation exists in the abnormal segregation band region at the center of hot rolled ferrite/pearlite steel, which results from the Mn segregation during solidification process of the continuous casting slab. The C–Mn segregation causes relative displacement of pearlite transformation curve and bainite transformation curve of C curve in the corresponding region, leading to bay-like shaped C curve. The bay-like shaped C curve creates conditions for the transformation from supercooling austenite to bainite at relatively lower cooling rate in this region. The Fe–Mn–C Atomic Segregation Zone (FASZ) caused by C–Mn segregation can powerfully retard the atomic motion, and increase the lattice reconstruction resistance of austenite transformation. These two factors provide thermodynamic and kinetic conditions for the bainite transformation, and result in the emergence of granular bainitic abnormal segregation band at the center of steel plate, which leads to lower plasticity and toughness of this region, and induces the layered fracture. - Highlights: • Scanning Auger Microprobe (SAM) is applied in the fracture analysis. • The abnormal segregation band region appears obvious C–Mn segregation. • The C–Mn segregation leads to bay-like shaped C curve. • The C–Mn segregation leads to Fe–Mn–C Atomic Segregation Zone.

  7. Residential segregation and birth weight among racial and ethnic minorities in the United States.

    Science.gov (United States)

    Walton, Emily

    2009-12-01

    Racial and ethnic minorities are often residentially segregated from whites in urban settings, a fact which has important health consequences. Research on the relationship between residential segregation and health outcomes lacks national-level investigation of racial and ethnic minority groups other than African Americans. I use multilevel analyses to examine the associations of residential isolation and clustering with birth weight among Asian, black, and Latino Americans using data from the National Center for Health Statistics' Natality Files and the U.S. Census. Findings indicate that segregation has a negative effect on the likelihood of having a low birth weight baby among Asian Americans, suggesting a possible concentration of social and structural resources in highly-segregated communities. On the contrary, segregation marginally increases the odds of low birth weight among African Americans, but only in the presence of higher poverty rates. Segregation does not affect birth weight among Latino Americans.

  8. 36 CFR 254.6 - Segregative effect.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 2 2010-07-01 2010-07-01 false Segregative effect. 254.6... ADJUSTMENTS Land Exchanges § 254.6 Segregative effect. (a) If a proposal is made to exchange Federal lands... segregative effect terminates as follows: (1) Automatically, upon issuance of a patent or other document of...

  9. Latent profile analysis of sixth graders based on teacher ratings: Association with school dropout.

    Science.gov (United States)

    Orpinas, Pamela; Raczynski, Katherine; Peters, Jaclyn Wetherington; Colman, Laura; Bandalos, Deborah

    2015-12-01

    The goal of this study was to identify meaningful groups of sixth graders with common characteristics based on teacher ratings of assets and maladaptive behaviors, describe dropout rates for each group, and examine the validity of these groups using students' self-reports. The sample consisted of racially diverse students (n = 675) attending sixth grade in public schools in Northeast Georgia. The majority of the sample was randomly selected; a smaller group was identified by teachers as high risk for aggression. Based on teacher ratings of externalizing behaviors, internalizing problems, academic skills, leadership, and social assets, latent profile analysis yielded 7 classes that can be displayed along a continuum: Well-Adapted, Average, Average-Social Skills Deficit, Internalizing, Externalizing, Disruptive Behavior with School Problems, and Severe Problems. Dropout rate was lowest for the Well-adapted class (4%) and highest for the Severe Problems class (58%). However, students in the Average-Social Skills Deficit class did not follow the continuum, with a large proportion of students who abandoned high school (29%). The proportion of students identified by teachers as high in aggression consistently increased across the continuum from none in the Well-Adapted class to 84% in the Severe Problems class. Students' self-reports were generally consistent with the latent profile classes. Students in the Well-Adapted class reported low aggression, drug use, and delinquency, and high life satisfaction; self-reports went in the opposite direction for the Disruptive Behaviors with School Problems class. Results highlight the importance of early interventions to improve academic performance, reduce externalizing behaviors, and enhance social assets. (c) 2015 APA, all rights reserved).

  10. Empathy scores in medical school and ratings of empathic behavior in residency training 3 years later.

    Science.gov (United States)

    Hojat, Mohammadreza; Mangione, Salvatore; Nasca, Thomas J; Gonnella, Joseph S; Magee, Mike

    2005-12-01

    The authors designed the present study to examine the association between individuals' scores on the Jefferson Scale of Physician Empathy (JSPE; M. Hojat, J. S. Gonnella, S. Mangione, T. J. Nasca, & M. Magee, 2003; M. Hojat, J. S. Gonnella, T. J. Nasca, S. Mangione, M. Vergare, & M. Magee, 2002; M. Hojat, S. Mangione, T. J. Nasca, M. J. M. Cohen, J. S. Gonnella, J. B. Erdmann, J. J. Veloski, & M. Magee, 2001), a self-report empathy scale, during medical school and ratings of their empathic behavior made by directors of their residency training programs 3 years later. Participants were 106 physicians. The authors examined the relationships between scores on the JSPE (with 20 Likert-type items) at the beginning of the students' 3rd year of medical school and ratings of their empathic behavior made by directors of their residency training programs. Top scorers on the JSPE in medical school, compared to Bottom scorers, obtained a significantly higher average rating of empathic behavior in residency 3 years later (p prosocial and helping behavior, it is important for investigators to further enhance our understanding of its correlates and outcomes among health professionals.

  11. State-level high school completion rates: Concepts, measures, and trends.

    Directory of Open Access Journals (Sweden)

    John Robert Warren

    2005-12-01

    Full Text Available Since the mid 1970s the national rate at which incoming 9th graders have completed high school has fallen slowly but steadily; this is also true in 41 states. In 2002, about three in every four students who might have completed high school actually did so; in some states this figure is substantially lower. In this paper I review state-level measures of high school completion rates and describe and validate a new measure that reports these rates for 1975 through 2002. Existing measures based on the Current Population Survey are conceptually imperfect and statistically unreliable. Measures based on Common Core Data (CCD dropout information are unavailable for many states and have different conceptual weaknesses. Existing measures based on CCD enrollment and completion data are systematically biased by migration, changes in cohort size, and/or grade retention. The new CCD-based measure described here is considerably less biased, performs differently in empirical analyses, and gives a different picture of the dropout situation across states and over time.

  12. Nonequilibrium Segregation in Petroleum Reservoirs

    DEFF Research Database (Denmark)

    Shapiro, Alexander; Stenby, Erling Halfdan

    1999-01-01

    We analyse adsorption of a multicomponent mixture at high pressure on the basis of the potential theory of adsorption. The adsorbate is considered as a segregated mixture in the external field produced by a solid adsorbent. we derive an analytical equation for the thickness of a multicomponent fi...... close to a dew point. This equation (asymptotic adsorption equation, AAE) is a first order approximation with regard to the distance from a phase envelope....

  13. Irradiation-induced segregation in multi-component alloys

    International Nuclear Information System (INIS)

    Chen, I.W.

    1983-01-01

    A unified analysis of irradiation-induced segregation in multi-component alloys is developed using the formulation of irreversible thermodynamics. Three distinct mechanisms for segregation, namely the inverse Kirkendall effect, the vacancy-wind effect, and the solute drag of interstitials, are identified. In particular, the inverse Kirkendall effect due to interstitials arises only if a solute-interstitial interaction or a mutual conversion among interstitials via lattice atom intermediaries operates simultaneously. In the limit of fast conversion a para-equilibrium state may be reached between interstitials and lattice atoms, and the interstitial mechanism becomes formally analogous to the vacancy mechanism. Although the past treatment of rate phenomena in this field was apparently limited to the latter case, the importance of the consideration of separate chemical potentials for interstitials of different species, in segregation and other irradiation effects, is emphasized. (orig.)

  14. Hating the Neighbors: The Role of Hate Crime in the Perpetuation of Black Residential Segregation

    Directory of Open Access Journals (Sweden)

    Ami M. Lynch

    2008-06-01

    Full Text Available Grounded in group conflict theory and the defended neighborhoods thesis, this nationwide empirical study of cities and their residential segregation levels examines the occurrence of hate crime using data for all U.S. cities with populations over 95,000 and Uniform Crime Reporting data for hate crime, in conjunction with 2000 census data. Hate crime is any illegal act motivated by pre-formed bias against, in this case, a person’s real or perceived race. This research asks: Do hate crime levels predict white/black segregation levels? How does hate crime predict different measures of white/black segregation? I use the dissimilarity index measure of segregation operationalized as a continuous, binary, and ordinal variable, to explore whether hate crime predicts segrega- tion of blacks from whites. In cities with higher rates of hate crime there was higher dissimilarity between whites and blacks, controlling for other factors. The segregation level was more likely to be “high” in a city where hate crime occurred. Blacks are continually multiply disadvantaged and distinctly affected by hate crime and residential segregation. Prior studies of residential segregation have focused almost exclusively on individual choice, residents’ lack of finances, or discriminatory actions that prevent racial minorities from moving, to explore the correlates of segregation. Notably absent from these studies are measures reflecting the level of hate crime occurring in cities. This study demonstrates the importance of considering hate crime and neighborhood conflict when contemplating the causes of residential segregation.

  15. Racial Discipline Disproportionality in Montessori and Traditional Public Schools: A Comparative Study Using the Relative Rate Index

    Directory of Open Access Journals (Sweden)

    Katie E. Brown

    2015-11-01

    Full Text Available Research from the past 40 years indicates that African American students are subjected to exclusionary discipline, including suspension and expulsion, at rates two to three times higher than their White peers (Children’s Defense Fund, 1975; Skiba, Michael, Nardo, & Peterson, 2002. Although this phenomenon has been studied extensively in traditional public schools, rates of racially disproportionate discipline in public Montessori schools have not been examined. The purpose of this study is to examine racial discipline disproportionality in Montessori public elementary schools as compared to traditional elementary schools. The Relative Rate Index (RRI is used as a measure of racially disproportionate use of out-of-school suspensions (Tobin & Vincent, 2011. Suspension data from the Office of Civil Rights Data Collection was used to generate RRIs for Montessori and traditional elementary schools in a large urban district in the Southeast. While statistically significant levels of racial discipline disproportionality are found in both the Montessori and traditional schools, the effect is substantially less pronounced in Montessori settings. These findings suggest that Montessori schools are not immune to racially disproportionate discipline and should work to incorporate more culturally responsive classroom management techniques. Conversely, the lower levels of racially disproportionate discipline in the Montessori schools suggests that further study of discipline in Montessori environments may provide lessons for traditional schools to promote equitable discipline.

  16. Effectiveness of school dental screening on stimulating dental attendance rates in Vikarabad town: A randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Gadde Praveen

    2014-01-01

    Full Text Available Background: The school dental screening program has been in existence from the beginning of 20 th century. Its value in encouraging attendance among school children is not fully established. Aim: The aim was to determine the effectiveness of school dental screening on stimulating dental attendance rates among school children in Vikarabad town. Objectives: (a To compare the dental attendance rates between 6-9 and 10-13 years old age groups, among male and female school children in Vikarabad town. (b To identify the type of dental treatment received by the school children. Materials and Methods: A randomized controlled trial was conducted among school children aged 6-13 years old from 16 schools that were randomly selected and divided into two groups. Eight schools had a dental screening program (study group = 300 children and had blanket referral cards and 8 schools that did not have the intervention (control group = 300. The dental attendance rates were determined after 3 months of follow-up period by evaluating the blanket referral cards for the study group and by an oral questionnaire for the control group. Results: The dental attendance rate was 27% for the study group and 18% for the control group which is statistically significant. The attendance rate was higher among 10-13 years of children both in test group and control groups. Among the children who visited the dentist, 53% in the control group and 69% from the test group got simple amalgam and glass ionomer cement restorations. Conclusion: The dental attendance rates were improved following school dental screening.

  17. Heart Rate Responses of High School Students Participating in Surfing Physical Education.

    Science.gov (United States)

    Bravo, Michelle M; Cummins, Kevin M; Nessler, Jeff A; Newcomer, Sean C

    2016-06-01

    Despite the nation's rising epidemic of childhood obesity and diabetes, schools struggle to promote physical activities that help reduce risks for cardiovascular disease. Emerging data suggest that adopting novel activities into physical education (PE) curriculum may serve as an effective strategy for increasing physical activity in children. The purpose of this investigation was to characterize activity in the water and heart rates (HRs) of high school students participating in surf PE courses. Twenty-four male (n = 20) and female (n = 4) high school students (mean age = 16.7 ± 1.0 years) who were enrolled in surf PE courses at 2 high schools participated in this investigation. Daily measurements of surfing durations, average HR, and maximum HR were made on the students with HR monitors (PolarFT1) over an 8-week period. In addition, HR and activity in the water was evaluated during a single session in a subset of students (n = 11) using a HR monitor (PolarRCX5) and a video camera (Canon HD). Activity and HR were synchronized and evaluated in 5-second intervals during data analyses. The average duration that PE students participated in surfing during class was 61.7 ± 1.0 minutes. Stationary, paddling, wave riding, and miscellaneous activities comprised 42.7 ± 9.5, 36.7 ± 7.9, 2.9 ± 1.4, and 17.8 ± 11.4 percent of the surf session, respectively. The average and maximum HRs during these activities were 131.1 ± 0.9 and 177.2 ± 1.0 b·min, respectively. These data suggest that high school students participating in surf PE attained HRs and durations that are consistent with recommendations with cardiovascular fitness and health. In the future, PE programs should consider incorporating other action sports into their curriculum to enhance cardiovascular health.

  18. [Tobacco use rate and associated factors in middle school students in China].

    Science.gov (United States)

    Xiao, L; Feng, G Z; Jiang, Y; Zhang, J R; Liu, L X

    2017-05-10

    Objective: To understand tobacco use rate and explore the factors associated with tobacco use in middle school students in China. Methods: A self-administered questionnaire survey was conducted among 155 117 eligible middle students selected through multi-stage stratified cluster sampling from 31 provinces of China. The questionnaire consists of the following topics: tobacco use and cessation, passive smoking, access to tobacco products, tobacco control and tobacco advertisement, and knowledge about and attitudes to tobacco. Software SAS 9.3 was used for sample weighting and data analysis. Results: Current tobacco use rate was 6.9 % in middle school students in China. The rate was higher in boys (11.2 % ) than in girls (2.2 % ), and in rural area (7.8 % ) than in urban area (4.8 % ). Students in western area had the highest tobacco use rate (10.3 % ), followed by the students in middle area (6.4 % ), and the rate in students in eastern area was lowest (4.5 % ). Parent smoking (especially mother smoking), friend smoking, teacher smoking, pocket money for a week>20 yuan, tobacco advertisement or promotion, passive smoking, misconception of tobacco addiction, active attitude to smoking behavior were the risk factors for tobacco use. Conclusions: Smoking rate in boys in China was higher than the average global level. A comprehensive intervention strategy by Framework Convention on Tobacco Control should be used to reduce tobacco use in adolescents, including health education, increasing cigarette price, banning tobacco advertisement and promotion, and smoke-free legislation.

  19. Public High School Four-Year On-Time Graduation Rates and Event Dropout Rates: School Years 2010-11 and 2011-12. First Look. NCES 2014-391

    Science.gov (United States)

    Stetser, Marie C.; Stillwell, Robert

    2014-01-01

    This National Center for Education Statistics (NCES) First Look report introduces new data for two separate measures of 4-year on-time graduation rates as well as event dropout rates for school year (SY) 2010-11 and SY 2011-12. Specifically this report provides the following: (1) Four-year adjusted cohort graduation rate (ACGR) data reported by…

  20. MINORITY LANGUAGES IN ESTONIAN SEGREGATIVE LANGUAGE ENVIRONMENTS

    Directory of Open Access Journals (Sweden)

    Elvira Küün

    2011-01-01

    Full Text Available The goal of this project in Estonia was to determine what languages are spoken by students from the 2nd to the 5th year of basic school at their homes in Tallinn, the capital of Estonia. At the same time, this problem was also studied in other segregated regions of Estonia: Kohtla-Järve and Maardu. According to the database of the population census from the year 2000 (Estonian Statistics Executive Office's census 2000, there are representatives of 142 ethnic groups living in Estonia, speaking a total of 109 native languages. At the same time, the database doesn’t state which languages are spoken at homes. The material presented in this article belongs to the research topic “Home Language of Basic School Students in Tallinn” from years 2007–2008, specifically financed and ordered by the Estonian Ministry of Education and Research (grant No. ETF 7065 in the framework of an international study called “Multilingual Project”. It was determined what language is dominating in everyday use, what are the factors for choosing the language for communication, what are the preferred languages and language skills. This study reflects the actual trends of the language situation in these cities.

  1. Socio-economic Segregation with (without) Competitive Education Policies: A Comparative Analysis of Argentina and Chile.

    Science.gov (United States)

    Narodowski, Mariano; Nores, Milagros

    2002-01-01

    The view that competition initiatives in education, such as Chile's introduction of vouchers, promote socioeconomic segregation in schools is questioned. Chile and Argentina have faced very different decentralization reforms, carried out within different regulatory frameworks, but have arrived at similar situations in terms of schools'…

  2. The Western States: Profound Diversity but Severe Segregation for Latino Students

    Science.gov (United States)

    Kucsera, John; Flaxman, Greg

    2012-01-01

    The U.S. Western region and its public schools are in the midst of its largest racial and economic transformation, as the area witnesses a shrinking white majority, a surging Latino minority, and a growing class of poor. These groups, along with blacks and Asian, more often than not attend very different and segregated schools both in educational…

  3. Fighting Segregation in Special Needs Education in the Netherlands: The Effects of Different Funding Models

    Science.gov (United States)

    Pijl, Sip Jan

    2016-01-01

    In the past few decades, the number of students attending segregated special schools in the Netherlands has risen considerably. In 1975, 2.2% of all students between 4 and 11 years old attended a special school, and this percentage almost doubled to 4.3% over the next 20 years. In order to stop further growth, two new education policies came into…

  4. A large scale study of the assessment of the social environment of middle and secondary schools: the validity and utility of teachers' ratings of school climate, cultural pluralism, and safety problems for understanding school effects and school improvement.

    Science.gov (United States)

    Brand, Stephen; Felner, Robert D; Seitsinger, Anne; Burns, Amy; Bolton, Natalie

    2008-10-01

    Due to changes in state and federal policies, as well as logistical and fiscal limitations, researchers must increasingly rely on teachers' reports of school climate dimensions in order to investigate the developmental impact of these dimensions, and to evaluate efforts to enhance the impact of school environments on the development of young adolescents. Teachers' climate ratings exhibited a robust dimensional structure, high levels of internal consistency, and moderate levels of stability over 1-and 2-year time spans. Teachers' climate ratings were also found to be related consistently with students' ratings. In three large-scale samples of schools, teachers' climate ratings were associated significantly and consistently with students' performance on standardized tests of academic achievement, and with indexes of their academic, behavioral, and socio-emotional adjustment.

  5. WCPSS High School Graduation Rates: 4-Year and 5-Year Cohort Rates 2011-12. Measuring Up. D&A Report No. 13.04

    Science.gov (United States)

    Regan, Roger

    2013-01-01

    The Wake County Public School System (WCPSS) four-year cohort graduation rate declined slightly to 80.6% in 2011-12 from 80.9% in the previous year. Disaggregated graduation rates for most racial and ethnic groups stayed nearly the same or declined slightly in 2011-12, but the rate for African-American students rose from 67.9% to 69.6%. The other…

  6. Prevalence rates and epidemiological risk factors for astigmatism in Singapore school children.

    Science.gov (United States)

    Tong, Louis; Saw, Seang-Mei; Carkeet, Andrew; Chan, Wai-Ying; Wu, Hui-Min; Tan, Donald

    2002-09-01

    This study examined the prevalence rate of astigmatism and its epidemiological risk factors in Singapore school children. In a study of school children aged 7 to 9 years old in two schools in Singapore in 1999, a detailed questionnaire was administered to parents regarding reading or close-work habits, past history of close-work, family history, and socioeconomic factors. Cycloplegic refraction was performed five times in each eye. Defining astigmatism as worse than or equal to 0.5, 0.75, and 1 D cylinder in the right eye, the prevalence of astigmatism was calculated. The study population consisted of 1028 children. The prevalence rate of astigmatism (worse than or equal to 1 D cylinder) was 19.2% (95% confidence interval, 16.8 to 21.6). This was not different between genders, ethnic groups, or age (p > 0.05). With-the-rule astigmatism was more common than against-the-rule astigmatism. The prevalence of astigmatism and myopia was 9.8% (95% confidence interval, 8.0 to 11.6). A high AC/A ratio was associated (p = 0.003) with astigmatism, even after exclusion of myopic children. On vectorial analysis, J0 and J45 were associated with the number of hours of playing video games, whereas J45 was also associated with computer use. Only J45 was associated to male gender, a high AC/A ratio, and a family history of myopia. The prevalence rate of astigmatism (> or = 1 D) was 19%. Playing video games and computer use may be associated with astigmatism severity, although the presence of astigmatism (> or = 1 D) was not associated with any nearwork factors. A family history of myopia was associated with oblique astigmatism severity. A high AC/A ratio is associated with astigmatism, and this requires further investigation.

  7. Assessing U.S. Public School Quality: The Advantages of Combining Internal "Consumer Ratings" with External NCLB Ratings

    Science.gov (United States)

    Price, Heather E.

    2016-01-01

    The school quality assessment process under No Child Left Behind (NCLB) is criticized for oversimplifying and overemphasizing standardized test results and unfairly targeting diverse, urban schools. There has been much development in alternative test score evaluations, especially value-added models. These developments have tilted the public…

  8. A Review of Greene (2002 High School Graduation Rates in the United States

    Directory of Open Access Journals (Sweden)

    Richard P. Phelps

    2005-09-01

    Full Text Available The - Greene Method- of calculating school - graduation rates- and the Manhattan Institute (MI criticisms of official graduation and completion statistics are outlined and scrutinized. The methodology fails to recognize the complexity of the issue and appears to ignore the considerable efforts that have been undertaken by education statisticians to remediate the problems inherent to these types of data. The Greene method for calculating completion ratios is simulated and found to have little to no reliability. It is recommended that anyone intent on reporting valid and reliable education indicators avoid use of the Greene Method.

  9. Educational Progression in Ghana: Gender and Spatial Variations in Longitudinal Trajectories of Junior High School Completion Rate

    Science.gov (United States)

    Ansong, David; Alhassan, Mustapha

    2016-01-01

    Completion of junior high school is a critical milestone in every Ghanaian child's educational trajectory and a critical step toward the transition to higher education. However, the rate of children completing junior high school still lags behind most educational indicators in Ghana. Far more attention is paid to ensuring that students enroll in…

  10. Segregation and differential settling in flocculated tailings

    Energy Technology Data Exchange (ETDEWEB)

    Farinato, R.S.; Mahmoudkhani, A.; Fenderson, T.; Watson, P. [Kemira, Atlanta, GA (United States)

    2010-07-01

    Untreated oil sands tailings have a high solids content, have poor dewaterability, and contain no aggregates. This PowerPoint presentation investigated segregation and differential settling in flocculated tailings. Tailings were treated with gypsum and various polymers. Cylinder settling, dynamic rheometry, particle size analysis, and microscopy techniques were used to characterize the composite tailings. The particles sizes of the samples were evaluated in relation to shear rate, bed depth, and treatment. The study showed that the gypsum-treated tailings had small aggregates, size stratification, a high solids content, and poor dewaterability. The polymer N-treated tailings had the lowest solids content, good dewaterability, and weak aggregates. The polymer A-treated tailings had a low solids content, very good dewaterability, and strong aggregates. The addition of a coagulant to the polymer-A treated tailings provided weaker aggregates and a higher solids content. tabs., figs.

  11. ESTATÍSTICAS DE DESEMPENHO ESCOLAR: O LADO AVESSO SCHOOL ACHIEVEMENT RATES: THE OTHER SIDE

    Directory of Open Access Journals (Sweden)

    Marília Pinto de Carvalho

    2001-12-01

    Full Text Available Algumas das principais políticas para a educação no País, hoje, centram-se sobre a "correção do fluxo escolar", isto é, a diminuição dos índices de evasão e repetência, assim como as diversas práticas de "aceleração". Os resultados dessas políticas são avaliados por meio de estatísticas de desempenho escolar, que vêm sendo alardeadas pelos governos federal e do estado de São Paulo como grandes vitórias. Este artigo pretende olhar o avesso da produção desses dados, isto é, buscar como eles vêm sendo produzidos e utilizados no cotidiano das escolas, suas interações com a cultura escolar e seus efeitos sobre a aprendizagem das crianças. Com esses objetivos, está baseado em dados obtidos em observações, entrevistas e consultas a documentos de uma escola pública de 1ª a 4ª séries do ensino fundamental, de um município da região metropolitana de São Paulo. Essa experiência de pesquisa relatada reforça a importância de nos posicionarmos a favor da permanência das crianças e jovens na escola, mas contra a maquiagem estatística da ignorância e do fracasso do sistema em ensinar.In Brazil, some of the most important educational policies are nowadays centered on reducing school failure rates. Their results are measured through academic achievement statistics that both The Federal Government and The State of São Paulo Government announce as great accomplishments. This paper looks at the other side of the production of these rates. It looks on how they are produced in the school day-to-day life. Based on classroom observations and interviews with the staff of a public elementary school in São Paulo, it concludes on the importance of reinforcing the school achievement of children and young people but, at the same time, of denouncing the statistical make up of school failure.

  12. Proximity of food retailers to schools and rates of overweight ninth grade students: an ecological study in California

    Directory of Open Access Journals (Sweden)

    Fulfrost Brian

    2011-01-01

    Full Text Available Abstract Background The prevalence of obesity and overweight in youth has increased dramatically since the 1980s, and some researchers hypothesize that increased consumption of low-nutrient, energy-dense foods is a key contributor. The potential importance of food retailers near schools has received increasing attention, but public health research and policy has focused primarily on fast food restaurants. Less is known about the relationship between overweight/obesity and other types of retailers. This study aims to investigate the potential associations between nearby 1 fast food restaurants, 2 convenience stores, and 3 supermarkets, and rates of overweight students in California schools. Methods We examined the rate of overweight ninth grade students in public schools in 2007 using linear regression. The percentage of overweight students per school was determined by a state required physical fitness test, with three different options for measuring individual body composition. Our key independent variables were the presence of three different types of retailers within 800 m network buffers of the schools. Additional independent variables included school ethnic, gender and socioeconomic composition, as well as urban/non-urban location. We obtained the data from the California Department of Education and ESRI, Inc. Results The presence of a convenience store within a 10-minute walking distance of a school was associated with a higher rate of overweight students than schools without nearby convenience stores, after controlling for all school-level variables in the regression (1.2%, 95% confidence interval 0.03, 2.36. Nearby fast food restaurants and supermarkets, however, were not associated with school rates of overweight students. Conclusions Public health researchers and policy-makers interested in the food environments outside schools should expand their recent focus on nearby fast food restaurants to include convenience stores, which may also

  13. Measuring hunger and satiety in primary school children. Validation of a new picture rating scale.

    Science.gov (United States)

    Bennett, Carmel; Blissett, Jackie

    2014-07-01

    Measuring hunger and satiety in children is essential to many studies of childhood eating behaviour. Few validated measures currently exist that allow children to make accurate and reliable ratings of hunger/satiety. Three studies aimed to validate the use of a new categorical rating scale in the context of estimated and real eating episodes. Forty-seven 6- to 8-year-olds participated in Study 1, which used a between-participant design. Results indicated that the majority of children were able to make estimated hunger/satiety ratings for a story character using the scale. No significant differences in the ratings of hunger/satiety of children measured before and after lunch were observed and likely causes are discussed. To account for inter-individual differences in hunger/satiety perceptions Study 2 employed a within-participant design. Fifty-four 5- to 7-year-olds participated and made estimated hunger/satiety ratings for a story character and real hunger/satiety ratings before and after lunch. The results indicated that the majority of children were able to use the scale to make estimated and real hunger and satiety ratings. Children were found to be significantly hungrier before compared to after lunch. As it was not possible to establish the types and quantities of food children ate for lunch a third study was carried out in a controlled laboratory environment. Thirty-six 6- to 9-year-olds participated in Study 3 and made hunger/satiety ratings before and after ingesting an ad libitum snack of known composition and quantity. Results indicated that children felt hungrier before than after the snack and that pre-snack hunger/satiety, and changes in hunger/satiety, were associated with snack intake. Overall, the studies indicate that the scale has potential for use with primary school children. Implications of the findings are discussed. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Digital morphogenesis via Schelling segregation

    Science.gov (United States)

    Barmpalias, George; Elwes, Richard; Lewis-Pye, Andrew

    2018-04-01

    Schelling’s model of segregation looks to explain the way in which particles or agents of two types may come to arrange themselves spatially into configurations consisting of large homogeneous clusters, i.e. connected regions consisting of only one type. As one of the earliest agent based models studied by economists and perhaps the most famous model of self-organising behaviour, it also has direct links to areas at the interface between computer science and statistical mechanics, such as the Ising model and the study of contagion and cascading phenomena in networks. While the model has been extensively studied it has largely resisted rigorous analysis, prior results from the literature generally pertaining to variants of the model which are tweaked so as to be amenable to standard techniques from statistical mechanics or stochastic evolutionary game theory. In Brandt et al (2012 Proc. 44th Annual ACM Symp. on Theory of Computing) provided the first rigorous analysis of the unperturbed model, for a specific set of input parameters. Here we provide a rigorous analysis of the model’s behaviour much more generally and establish some surprising forms of threshold behaviour, notably the existence of situations where an increased level of intolerance for neighbouring agents of opposite type leads almost certainly to decreased segregation.

  15. From particle segregation to the granular clock

    International Nuclear Information System (INIS)

    Lambiotte, R.; Salazar, J.M.; Brenig, L.

    2005-01-01

    Recently several authors studied the segregation of particles for a system composed of mono-dispersed inelastic spheres contained in a box divided by a wall in the middle. The system exhibited a symmetry breaking leading to an overpopulation of particles in one side of the box. Here we study the segregation of a mixture of particles composed of inelastic hard spheres and fluidized by a vibrating wall. Our numerical simulations show a rich phenomenology: horizontal segregation and periodic behavior. We also propose an empirical system of ODEs representing the proportion of each type of particles and the segregation flux of particles. These equations reproduce the major features observed by the simulations

  16. From particle segregation to the granular clock

    Energy Technology Data Exchange (ETDEWEB)

    Lambiotte, R. [Physique Statistique, Plasmas et Optique Non-lineaire, Universite Libre de Bruxelles, Campus Plaine, Boulevard du Triomphe, Code Postal 231, 1050 Brussels (Belgium)]. E-mail: rlambiot@ulb.ac.be; Salazar, J.M. [Universite De Bougogne-LRRS UMR-5613 CNRS, Faculte des Sciences Mirande, 9 Av. Alain Savary, 21078 Dijon Cedex (France)]. E-mail: jmarcos@u-bourgogne.fr; Brenig, L. [Physique Statistique, Plasmas et Optique Non-lineaire, Universite Libre de Bruxelles, Campus Plaine, Boulevard du Triomphe, Code Postal 231, 1050 Brussels (Belgium)]. E-mail: lbrenig@ulb.ac.be

    2005-08-01

    Recently several authors studied the segregation of particles for a system composed of mono-dispersed inelastic spheres contained in a box divided by a wall in the middle. The system exhibited a symmetry breaking leading to an overpopulation of particles in one side of the box. Here we study the segregation of a mixture of particles composed of inelastic hard spheres and fluidized by a vibrating wall. Our numerical simulations show a rich phenomenology: horizontal segregation and periodic behavior. We also propose an empirical system of ODEs representing the proportion of each type of particles and the segregation flux of particles. These equations reproduce the major features observed by the simulations.

  17. Relationship between Self-Rated Health and Lifestyle and Food Habits in Japanese High School Students

    Directory of Open Access Journals (Sweden)

    Tomoko Osera

    2017-10-01

    Full Text Available Self-rated health (SRH, a subjective assessment of health status, is extensively used in the field of public health. It is an important and valid measure that is strongly related to morbidity, mortality, longevity and health status. Adolescence is a crucial period for the formation of health status, because health-risk behaviours (e.g., skipping breakfast are often established during this period. In this study, we investigated the relationship of SRH with lifestyle and eating habits in Japanese high school students. In this study, 1296 students aged 16–18 years from 11 high schools in Japan participated. A questionnaire was administered to these participants that included a question on SRH, five questions on demographic characteristics, six questions on lifestyle items (e.g., wake-up time, five questions on miscellaneous health issues (e.g., anorexia, and 25 questions on food habits and attitudes towards food. We examined the differences between self-rated healthy and unhealthy groups using logistic regression analysis adjusted for gender and age. A dichotomy regression analysis was performed using a stepwise elimination method. Of the 1296 respondents, 16.7% reported feeling unhealthy, 57.7% of whom were females. The self-rated healthy group had a higher frequency of eating breakfast (odds ratio (OR: 2.13; confidence interval (CI: 1.07–4.24 and liked home meals to a greater extent (OR: 3.12; CI: 1.27–7.65 than the self-rated unhealthy group. The two groups did not differ significantly in terms of other lifestyle factors or unidentified complaints. Our results suggest that liking home meals during adolescence may lead to the development of good eating habits, i.e., eating breakfast, and better SRH.

  18. Relationship between Self-Rated Health and Lifestyle and Food Habits in Japanese High School Students.

    Science.gov (United States)

    Osera, Tomoko; Awai, Mitsuyo; Kobayashi, Misako; Tsutie, Setsuko; Kurihara, Nobutaka

    2017-10-18

    Self-rated health (SRH), a subjective assessment of health status, is extensively used in the field of public health. It is an important and valid measure that is strongly related to morbidity, mortality, longevity and health status. Adolescence is a crucial period for the formation of health status, because health-risk behaviours (e.g., skipping breakfast) are often established during this period. In this study, we investigated the relationship of SRH with lifestyle and eating habits in Japanese high school students. In this study, 1296 students aged 16-18 years from 11 high schools in Japan participated. A questionnaire was administered to these participants that included a question on SRH, five questions on demographic characteristics, six questions on lifestyle items (e.g., wake-up time), five questions on miscellaneous health issues (e.g., anorexia), and 25 questions on food habits and attitudes towards food. We examined the differences between self-rated healthy and unhealthy groups using logistic regression analysis adjusted for gender and age. A dichotomy regression analysis was performed using a stepwise elimination method. Of the 1296 respondents, 16.7% reported feeling unhealthy, 57.7% of whom were females. The self-rated healthy group had a higher frequency of eating breakfast (odds ratio (OR): 2.13; confidence interval (CI): 1.07-4.24) and liked home meals to a greater extent (OR: 3.12; CI: 1.27-7.65) than the self-rated unhealthy group. The two groups did not differ significantly in terms of other lifestyle factors or unidentified complaints. Our results suggest that liking home meals during adolescence may lead to the development of good eating habits, i.e., eating breakfast, and better SRH.

  19. Publication Rates of Social and Administrative Sciences Pharmacy Faculty in Non-Research Intensive Pharmacy Schools.

    Science.gov (United States)

    Weathers, Trenna; Unni, Elizabeth

    2018-04-01

    Objective. To assess the level of publication rates from 2011 through 2015 by Social and Administrative Sciences (SAS) faculty at non-research intensive pharmacy schools. Methods. The Web of Science database was searched using faculty names identified from the American Association of Colleges of Pharmacy (AACP) faculty and professional staff roster. Publication rates of SAS faculty were calculated and compared using several demographic subcategories such as public/private school, part of an academic health center, schools with PhD program, funding status, etc. Results. The 208 SAS faculty members from 59 colleges contributed to 478 publications with a mean of 95.6 publications per year and 1.62 publications per institution per year. The number of publications increased 45% over the five years from 67 publications in 2011 to 122 in 2015.The average number of publications was 0.92 per year per SAS faculty compared to 0.82 publications per year per faculty from other basic pharmaceutical sciences divisions. The most commonly published research was research articles in the area of scholarship of teaching and learning. The significant predictors of publications were being part of an academic health center, having a PhD program, and higher percent of faculty members who are SAS faculty. Conclusion. Despite being affiliated with institutions with missions less targeted on research, this study showed SAS faculty members at non-research intensive institutions consistently contribute to published literature. Further studies are needed to examine reasons for the lack of publishing by almost half of the SAS faculty and ways to increase research and publication in the field of SAS.

  20. Radiation-induced segregation behavior in random and ordered face-centered cubic materials

    International Nuclear Information System (INIS)

    Bui, T.X.; Robertson, I.M.; Klatt, J.L.; Averback, R.S.; Kirk, M.A.

    1993-01-01

    Radiation-induced segregation has been studied in random solid solution alloys Ni-10%Al and Ni-6%Si, and in the ordered (L1 2 structure) intermetallics Ni 3 Si and Ni 3 Al. These materials were irradiated with 2 MeV He + ions at a temperature between 0.45 and 0.55T m and at an ion dose rate of approximately 1x10 -4 dpa per second. Subsequent Auger Electron Spectroscopy analysis showed that silicon segregated to the surface in the Ni-6% Si and Ni 3 Si alloys, and aluminum segregated away from the near surface region in the Ni-10% Al alloy. The Ni 3 Al samples exhibited no detectable segregation with respect to depth from the sample surface. The mechanisms that may give rise to this resistance to radiation induced segregation will be examined in terms of the mobility of the alloying constituents, ordering energies and atomic sizes. (orig.)

  1. Increased spontaneous mitotic segregation in MMS-sensitive mutants of Saccharomyces cerevisiae

    International Nuclear Information System (INIS)

    Prakash, S.; Prakash, L.

    1977-01-01

    Methyl methanesulfonate (MMS)-sensitive mutants of Saccharomyces cerevisiae belonging to four different complementation groups, when homozygous, increase the rate of spontaneous mitotic segregation to canavanine resistance from heterozygous sensitive (can/sup r//+) diploids by 13- to 170-fold. The mms8-1 mutant is MMS and x-ray sensitive and increases the rate of spontaneous mitotic segregation 170-fold. The mms9-1 and mms13-1 mutants are sensitive to x rays and uv, respectively, in addition to MMS, and increase the rate of spontaneous mitotic segregation by 13-fold and 85-fold, respectively. The mutant mms21-1 is sensitive to MMS, x rays and uv and increases the rate of spontaneous mitotic segregation 23-fold

  2. Crime rates and sedentary behavior among 4th grade Texas school children

    Directory of Open Access Journals (Sweden)

    Hoelscher Deanna M

    2008-05-01

    Full Text Available Abstract Introduction Although per capita crime has generally fallen over the period which coincides with the obesity epidemic, it has not fallen uniformly across communities. It also has not fallen enough to allay fears on the part of parents. Over the past 30 years, technological changes have made the indoor alternatives to playing outside, where children are more vulnerable to criminal activity, more enjoyable (cable TV, video games, and the internet and comfortable (the spread of air conditioning to low income neighborhoods. We determined whether indoor sedentary behavior patterns are associated with community crime statistics. 4th graders in the U.S. are typically 9 or 10 years old. Methods We used data from the 2004–2005 Texas School Physical Activity and Nutrition (SPAN survey linked with U.S. Department of Justice, Office of Justice Programs, Bureau of Justice Statistics data for the years 2000 through 2005 and Texas State data on sexual offenders. The probability-based sample included a total of 7,907 children in grade four. Multistage probability sampling weights were used. The dependent variables included were hours of TV watching, video game playing, computer use and total indoor sedentary behavior after school. Incremental Relative Rates were computed for community crime rates including robberies, all violent crimes, murders, assaults, property crimes, rapes, burglaries, larcenies and motor vehicle thefts as well as for sexual offenders living in the neighborhood. The neighborhood refers to the areas where the students at each school live. In the case of sexual offenders, sexual offenders per capita are estimated using the per capita rate in the zip code of the school attended; all other crime statistics are estimated by the crimes per capita in the police department jurisdiction covering the school attended. After controlling for sex, age, and African-American and Hispanic, cross-sectional associations were determined using

  3. Study of the Formation Mechanism of A-Segregation Based on Microstructural Morphology

    Science.gov (United States)

    Zhang, Zhao; Bao, Yuchong; Liu, Lin; Pian, Song; Li, Ri

    2018-04-01

    A model that combines a cellular automaton (CA) and lattice Boltzmann method (LBM) is presented. The mechanism of A-segregation in an Fe-0.34 wt pct C alloy ingot is analyzed on the basis of microstructural morphology calculations. The CA is used to capture the solid/liquid interface, while the LBM is used to calculate the transport phenomena. (1) The solidification of global columnar dendrites was simulated, and two obvious A-segregation bands appeared in the middle-radius region between the ingot wall surface and the centerline. In addition, the angle of deflection to the centerline increased with the increasing heat dissipation rate of the wall surface. When natural convection was ignored, the A-segregation disappeared, and only positive segregation was present in the center and bottom corner of the ingot. (2) Mixed columnar-equiaxed solidification was simulated. Many A-segregation bands appeared in the ingot. (3) Global equiaxed solidification was simulated, and no A-segregation bands were found. The results show that the upward movement of the high-concentration melt is the key to the formation of A-segregation bands, and remelting and the emergence of equiaxed grains are not necessary conditions to develop these bands. However, the appearance of equiaxed grains accelerates the formation of vortexes; thus, many A-segregation bands appear during columnar-equiaxed solidification.

  4. Spiral of Decline or "Beacon of Hope": Stories of School Choice in a Dual Language School

    Science.gov (United States)

    Pearson, Timothy; Wolgemuth, Jennifer R.; Colomer, Soria E.

    2015-01-01

    Public schools in some areas of the U.S. are as segregated as they were prior to court-ordered busing, in part due to school choice policies that appear to exacerbate extant segregation. In particular, Latina/o students are increasingly isolated in schools characterized as being in cycles of decline. Our case study of one such school is based on a…

  5. Segregating photoelastic particles in free-surface granular flows

    Science.gov (United States)

    Thomas, Amalia; Vriend, Nathalie; Environmental; Industrial Fluid Dynamics Team

    2017-11-01

    We present results from a novel experimental set-up creating 2D avalanches of photoelastic discs. Two distinct hoppers supply either monodisperse or bidisperse particles at adjustable flow-rates into a 2 meter long, narrow acrylic chute inclined at 20°. For 20-40 seconds the avalanche maintains a steady-state that accelerates and thins downstream. The chute basal roughness is variable, allowing for different flow profiles. Using a set of polarizers and a high-speed camera, we visualize and quantify the forces due to dynamic interactions between the discs using photoelastic theory. Velocity and density profiles are derived from particle tracking at different distances from the discharge point and are coarse-grained to obtain continuous fields. With the access to both force information and dynamical properties via particle-tracking, we can experimentally validate existing mu(I) and non-local rheologies. As an extension, we probe the effect of granular segregation in bimodal mixtures by using the two separate inflow hoppers. We derive the state of segregation along the avalanche channel and measure the segregation velocities of each species. This provides insight in, and a unique validation of, the fundamental physical processes that drive segregation in avalanching geometries.

  6. Kinetics of radiation-induced segregation in ternary alloys

    International Nuclear Information System (INIS)

    Lam, N.O.; Kumar, A.; Wiedersich, H.

    1982-01-01

    Model calculations of radiation-induced segregation in ternary alloys have been performed, using a simple theory. The theoretical model describes the coupling between the fluxes of radiation-induced defects and alloying elements in an alloy A-B-C by partitioning the defect fluxes into those occurring via A-, B-, and C-atoms, and the atom fluxes into those taking place via vacancies and interstitials. The defect and atom fluxes can be expressed in terms of concentrations and concentration gradients of all the species present. With reasonable simplifications, the radiation-induced segregation problem can be cast into a system of four coupled partial-differential equations, which can be solved numerically for appropriate initial and boundary conditions. Model calculations have been performed for ternary solid solutions intended to be representative of Fe-Cr-Ni and Ni-Al-Si alloys under various irradiation conditions. The dependence of segregation on both the alloy properties and the irradiation variables, e.g., temperature and displacement rate, was calculated. The sample calculations are in good qualitative agreement with the general trends of radiation-induced segregation observed experimentally

  7. Residential Segregation in Texas in 1980.

    Science.gov (United States)

    Hwang, Sean-Shong; Murdock, Steve H.

    1982-01-01

    Between 1970 and 1980 racial and ethnic segregation for major Texas cities declined for all groups, but declines were small between Anglo and Spanish groups. Segregation is unaffected by variation in size of city, percent of population that is Spanish or Black, or central city status. (Author/AM)

  8. Housing Systems and Ethnic Spatial Segregation

    DEFF Research Database (Denmark)

    Andersen, Hans Skifter; Andersson, Roger; Wessel, Terje

    Residential spatial segregation is related to housing markets and housing policies. In this paper, ethnic segregation is compared across four Nordic capitals and explanations for the differences are examined by comparing the housing markets and housing policies of the countries. The housing markets...

  9. Occupational Segregation by Sex: Determinants and Changes.

    Science.gov (United States)

    Beller, Andrea H.

    1982-01-01

    This study found that occupational sex segregation began to diminish during the 1970s, in conjunction with enforcement of the equal employment opportunity laws against sex discrimination in employment. The success of these laws suggests that discrimination was originally a determinant of occupational segregation. (Author/SK)

  10. Sex Segregation in Undergraduate Engineering Majors

    Science.gov (United States)

    Litzler, Elizabeth

    2010-01-01

    Gender inequality in engineering persists in spite of women reaching parity in college enrollments and degrees granted. To date, no analyses of educational sex segregation have comprehensively examined segregation within one discipline. To move beyond traditional methods of studying the long-standing stratification by field of study in higher…

  11. Administrative Segregation for Mentally Ill Inmates

    Science.gov (United States)

    O'Keefe, Maureen L.

    2007-01-01

    Largely the result of prison officials needing to safely and efficiently manage a volatile inmate population, administrative segregation or supermax facilities are criticized as violating basic human needs, particularly for mentally ill inmates. The present study compared Colorado offenders with mental illness (OMIs) to nonOMIs in segregated and…

  12. Class, Kinship Density, and Conjugal Role Segregation.

    Science.gov (United States)

    Hill, Malcolm D.

    1988-01-01

    Studied conjugal role segregation in 150 married women from intact families in working-class community. Found that, although involvement in dense kinship networks was associated with conjugal role segregation, respondents' attitudes toward marital roles and phase of family cycle when young children were present were more powerful predictors of…

  13. A sexy spin on nonrandom chromosome segregation.

    Science.gov (United States)

    Charville, Gregory W; Rando, Thomas A

    2013-06-06

    Nonrandom chromosome segregation is an intriguing phenomenon linked to certain asymmetric stem cell divisions. In a recent report in Nature, Yadlapalli and Yamashita (2013) observe nonrandom segregation of X and Y chromosomes in Drosophila germline stem cells and shed light on the complex mechanisms of this fascinating process. Copyright © 2013 Elsevier Inc. All rights reserved.

  14. Children Receiving Free or Reduced-Price School Lunch Have Higher Food Insufficiency Rates in Summer.

    Science.gov (United States)

    Huang, Jin; Barnidge, Ellen; Kim, Youngmi

    2015-09-01

    In 2012, 20% of households in the United States with children lacked consistent access to adequate food. Food insufficiency has significant implications for children, including poor physical and mental health outcomes, behavior problems, and low educational achievements. The National School Lunch Program (NSLP) is one policy solution to reduce food insufficiency among children from low-income families. The objective of this project was to evaluate the association between NSLP participation and household food insufficiency by examining trajectories of food insufficiency over 10 calendar months. The calendar months included both nonsummer months when school is in session and summer months when school is out of session. The study used the data from the Survey of Income and Program Participation and conducted linear growth curve analyses in the multilevel modeling context. Comparisons were made between the trajectories of food insufficiencies among recipients of free or reduced-price lunch and their counterparts who are eligible but choose not to participate in the program. Heads of households that included children receiving free or reduced-price lunch (n = 6867) were more likely to be female, black, unmarried, and unemployed, and have a lower educational attainment than those whose children were eligible but did not receive free or reduced-price lunch (n = 11,396). For households participating in the NSLP, the food insufficiency rate was consistent from January to May at ∼4%, and then increased in June and July to >5%. Meanwhile, food insufficiency among eligible nonrecipients was constant throughout the year at nearly 2%. The NSLP protects households from food insufficiency. Policies should be instituted to make enrollment easier for households. © 2015 American Society for Nutrition.

  15. An Empirical Assessment of Dropout Rate of Learners at Selected High Schools in King William’s Town, South Africa

    Directory of Open Access Journals (Sweden)

    Wendy Manona

    2015-12-01

    Full Text Available This study investigated and analysed factors responsible for high dropout rate of learners at selected high schools in King William’s Town District, Province of the Eastern Cape. The aim of the study is provide an understanding into inherent problems of early exit of learners in the education sector, which impede the long-term production of professionals with bright future. The main findings of this study revealed that multiple motives, associated with individual characteristics of dropouts and social problems emanating from their family background and influence of the community, prompted learners to dropout. Moreover, learner dropout is inter alia caused by social factors such as lack of resources, the effect of poverty, orphans at school, the distance between the school and the community, drug abuse, pregnancy and HIV and AIDS prevalence in schools, gangsterism and learning barriers. The results of this research suggest that the government should make resources available with regard to scholar transport, school nurses to provide education awareness programmes in relation to early pregnancies, HIV and AIDS infection to improve attendance rate. The Department of Social Development should provide information with regard to benefits available to orphaned learners. The government should ensure sustainable provision of the school nutrition programme to alleviate hunger and poverty. School management should effectively regulate the behaviour of learners to promote discipline in schools so that substance abuse is eliminated.

  16. Every Student Succeeds Act High School Graduation Rate: Non-Regulatory Guidance

    Science.gov (United States)

    US Department of Education, 2017

    2017-01-01

    Student graduation from high school with a regular high school diploma is an important indicator of school success and one of the most significant indicators of student college and career readiness. In addition, there are substantial economic benefits to high school completion. For example, according to the U.S. Department of Education's National…

  17. Youth Walking and Biking Rates Vary by Environments around 5 Louisiana Schools

    Science.gov (United States)

    Gustat, Jeanette; Richards, Katherine; Rice, Janet; Andersen, Lori; Parker-Karst, Kathryn; Cole, Shalanda

    2015-01-01

    Background: The prevalence of obesity in children is high, and many do not meet physical activity recommendations. The Safe Routes to School (SRTS) program encourages school-aged children to walk and bike to school. We assessed the condition of the walking/biking environment around schools in Louisiana prior to the state's first SRTS program.…

  18. Controlling mixing and segregation in time periodic granular flows

    Science.gov (United States)

    Bhattacharya, Tathagata

    Segregation is a major problem for many solids processing industries. Differences in particle size or density can lead to flow-induced segregation. In the present work, we employ the discrete element method (DEM)---one type of particle dynamics (PD) technique---to investigate the mixing and segregation of granular material in some prototypical solid handling devices, such as a rotating drum and chute. In DEM, one calculates the trajectories of individual particles based on Newton's laws of motion by employing suitable contact force models and a collision detection algorithm. Recently, it has been suggested that segregation in particle mixers can be thwarted if the particle flow is inverted at a rate above a critical forcing frequency. Further, it has been hypothesized that, for a rotating drum, the effectiveness of this technique can be linked to the probability distribution of the number of times a particle passes through the flowing layer per rotation of the drum. In the first portion of this work, various configurations of solid mixers are numerically and experimentally studied to investigate the conditions for improved mixing in light of these hypotheses. Besides rotating drums, many studies of granular flow have focused on gravity driven chute flows owing to its practical importance in granular transportation and to the fact that the relative simplicity of this type of flow allows for development and testing of new theories. In this part of the work, we observe the deposition behavior of both mono-sized and polydisperse dry granular materials in an inclined chute flow. The effects of different parameters such as chute angle, particle size, falling height and charge amount on the mass fraction distribution of granular materials after deposition are investigated. The simulation results obtained using DEM are compared with the experimental findings and a high degree of agreement is observed. Tuning of the underlying contact force parameters allows the achievement

  19. Grain boundary segregation and intergranular failure

    International Nuclear Information System (INIS)

    White, C.L.

    1980-01-01

    Trace elements and impurities often segregate strongly to grain boundaries in metals and alloys. Concentrations of these elements at grain boundaries are often 10 3 to 10 5 times as great as their overall concentration in the alloy. Because of such segregation, certain trace elements can exert a disproportionate influence on material properties. One frequently observed consequence of trace element segregation to grain boundaries is the occurrence of grain boundary failure and low ductility. Less well known are incidences of improved ductility and inhibition of grain boundary fracture resulting from trace element segregation to grain boundaries in certain systems. An overview of trace element segregation and intergranular failure in a variety of alloy systems as well as preliminary results from studies on Al 3% Li will be presented

  20. Trends in High School Dropout and Completion Rates in the United States: 2014. NCES 2018-117

    Science.gov (United States)

    McFarland, Joel; Cui, Jiashan; Stark, Patrick

    2018-01-01

    This report draws on an array of nationally representative surveys and administrative datasets to present statistics on high school dropout and completion rates. The report includes estimates of the percentage of students who drop out in a given 12-month period (event dropout rates), the percentage of young people in a specified age range who are…

  1. Relations between Perceived Competence, Importance Ratings, and Self-Worth among African American School-Age Children

    Science.gov (United States)

    Grier, Leslie K.

    2013-01-01

    The purpose of this research was to investigate how domain-specific importance ratings affect relations between perceived competence and self-worth among African American school-age children. Importance ratings have been found to affect the strength of the relationship between perceived competence and self-worth and have implications for…

  2. The Impact of Tobacco-Free School Policies on Youth Smoking Rates in Florida Public School Districts

    Science.gov (United States)

    Terry, Amanda; Zhang, Ning Jackie

    2016-01-01

    Background: Developing and implementing policies to curb and prevent youth tobacco use is of the utmost importance. In Florida, public school districts were authorized to develop tobacco-free school policies through an amendment to the Florida Clean Indoor Air Act in 2011. The purpose of this study is to determine the impact of tobacco-free school…

  3. Self-rated health and wellbeing among school-aged children with and without special educational needs: Differences between mainstream and special schools.

    Science.gov (United States)

    Rathmann, Katharina; Vockert, Theres; Bilz, Ludwig; Gebhardt, Markus; Hurrelmann, Klaus

    2018-05-11

    Studies among students with special educational needs (SEN) in separate special schools (SSS) and mainstream schools (MS) are particularly applicable to educational attainment and social participation. However, indicators of health and wellbeing have rarely been considered. This study investigates two related topics: first, health and wellbeing differences between students with SEN in special schools (SSS) and students without SEN in regular schools, and second, the rarely considered question whether health and wellbeing among students with SEN differ between school settings (i.e. MS vs. SSS). Bivariate and multilevel analyses are applied with data from the German National Educational Panel Study (NEPS) with 5267 students (grade 7). After having controlled for background characteristics, students in SSS report higher likelihoods of poor self-rated health compared to students in higher track schools. Self-rated health of students with SEN does not significantly differ between MS vs. SSS. For life satisfaction, students with SEN show higher likelihoods of low life satisfaction when attending MS. Teachers in inclusive settings are encouraged to establish class work and teaching that support a real change from class placement to inclusive culture in order to suitably support students with SEN. Copyright © 2018 Elsevier Ltd. All rights reserved.

  4. Effect of the Transcendental Meditation Program on Graduation, College Acceptance and Dropout Rates for Students Attending an Urban Public High School

    Science.gov (United States)

    Colbert, Robert D.

    2013-01-01

    High school graduation rates nationally have declined in recent years, despite public and private efforts. The purpose of the current study was to determine whether practice of the Quiet Time/Transcendental Meditation® program at a medium-size urban school results in higher school graduation rates compared to students who do not receive training…

  5. Residential segregation and the health of African-American infants: does the effect vary by prevalence?

    Science.gov (United States)

    Nyarko, Kwame A; Wehby, George L

    2012-10-01

    Segregation effects may vary between areas (e.g., counties) of low and high low birth weight (LBW; birth (PTB; rates due to interactions with area differences in risks and resources. We assess whether the effects of residential segregation on county-level LBW and PTB rates for African-American infants vary by the prevalence of these conditions. The study sample includes 368 counties of 100,000 or more residents and at least 50 African-American live births in 2000. Residentially segregated counties are identified alternatively by county-level dissimilarity and isolation indices. Quantile regression is used to assess how residential segregation affects the entire distributions of county-level LBW and PTB rates (i.e. by prevalence). Residential segregation increases LBW and PTB rates significantly in areas of low prevalence, but has no such effects for areas of high prevalence. As a sensitivity analysis, we use metropolitan statistical area level data and obtain similar results. Our findings suggest that residential segregation has adverse effects mainly in areas of low prevalence of LBW and preterm birth, which are expected overall to have fewer risk factors and more resources for infant health, but not in high prevalence areas, which are expected to have more risk factors and fewer resources. Residential policies aimed at area resource improvements may be more effective.

  6. Segregation of solid waste from a fish-processing industry: a sustainable action

    Directory of Open Access Journals (Sweden)

    Yeda dos Santos Silva

    2018-05-01

    Full Text Available Segregation techniques represent a sustainable alternative to minimize wastes of raw material in processing industries. This study considered the premise; its purpose was to use segregation techniques to determine the theoretical removal rate of solid compounds present in processing effluents, in order to support the sustainable development of the fish industry. The removal rates obtained for different treatments were evaluated for the parameters: total solids, organic matter and oils and greases, and the efficiency of the segregation of the effluent streams in the different stages of fish processing was evaluated through descriptive statistical analysis. The segregation recovered from 31% to 70% of total solids; from 15% to 97.50% of organic matter, and from 10% to 63% of oils and greases. These results indicates that the raw material can be used in new products, leading to reduced final-effluent concentration.

  7. Boys starting school disadvantaged: implications from teachers' ratings of behaviour and achievement in the first two years.

    Science.gov (United States)

    Childs, G; McKay, M

    2001-06-01

    Consistent evidence indicates that low socio-economic status (SES) acts as an important stressor and vulnerability factor for children's school learning. However, specific mechanism(s) of this process are still not well understood. This study was a follow-up of the classroom learning behaviour and perceived achievement of low and middle income children after two years at school, who had previously been rated soon after starting school. It examined whether teachers' ratings displayed predictive stability over that period, and whether significant differences evident at age 5 in SES and gender were still operative at age 7. Two samples, of low income (N = 85) and middle income (N = 63) children, were rated following school entry (mean age 5 years 3 months) and rated again after two years at school. The children were rated at both points by their regular classroom teachers using the Learning Behaviours Scale (Stott et al., 1998) with subscales of Distractible, Apprehensive and Uncooperative, together with ratings of academic achievement and their personal perception of each child. SES was found to be a very limited predictor for the learning behaviour subscale ratings and for teachers' personal perceptions at both ages 5 and 7. SES did significantly predict expected Academic Achievement at age 5, but this effect disappeared completely by age 7. Conversely, within the two defined groups, Low Income boys were found to display significantly poorer learning behaviours at age 5, especially in terms of distractible behaviour, compared with Middle Income boys and with girls generally. This pattern was maintained over the next two years of their schooling. The effect of SES was thus demonstrated more powerfully in between-group differences than by means of regression. The findings emphasised the persistence of teachers' initial negative impressions about distractible 'hard to manage' boys from low SES families. The outcomes of this study suggest that low SES boys commenced

  8. Do High Schools Implementing SWPBIS Have Lower Rates of Illegal Drug and Alcohol Use?

    Science.gov (United States)

    Bastable, Eoin; Kittelman, Angus; McIntosh, Kent; Hoselton, Rob

    2015-01-01

    School-wide positive behavioral interventions and supports (SWPBIS) is a systems-level framework for improving social and academic outcomes for students in schools through the use of integrated evidence-based practices. Although the effects of SWPBIS are well-documented in elementary schools, there is increasing interest in implementing SWPBIS in…

  9. The Effects of Intradistrict School Mobility and High Student Turnover Rates on Early Reading Achievement

    Science.gov (United States)

    LeBoeuf, Whitney A.

    2013-01-01

    A number of studies have identified school mobility as one form of school disengagement that is disproportionately harmful for young children enrolled in large urban districts. However, there is substantial variation in these findings, with some studies actually evidencing positive associations between school mobility and academic outcomes (Mehana…

  10. Genes that bias Mendelian segregation.

    Science.gov (United States)

    Grognet, Pierre; Lalucque, Hervé; Malagnac, Fabienne; Silar, Philippe

    2014-01-01

    Mendel laws of inheritance can be cheated by Meiotic Drive Elements (MDs), complex nuclear genetic loci found in various eukaryotic genomes and distorting segregation in their favor. Here, we identify and characterize in the model fungus Podospora anserina Spok1 and Spok2, two MDs known as Spore Killers. We show that they are related genes with both spore-killing distorter and spore-protecting responder activities carried out by the same allele. These alleles act as autonomous elements, exert their effects independently of their location in the genome and can act as MDs in other fungi. Additionally, Spok1 acts as a resistance factor to Spok2 killing. Genetical data and cytological analysis of Spok1 and Spok2 localization during the killing process suggest a complex mode of action for Spok proteins. Spok1 and Spok2 belong to a multigene family prevalent in the genomes of many ascomycetes. As they have no obvious cellular role, Spok1 and Spok2 Spore Killer genes represent a novel kind of selfish genetic elements prevalent in fungal genome that proliferate through meiotic distortion.

  11. Genes that bias Mendelian segregation.

    Directory of Open Access Journals (Sweden)

    Pierre Grognet

    Full Text Available Mendel laws of inheritance can be cheated by Meiotic Drive Elements (MDs, complex nuclear genetic loci found in various eukaryotic genomes and distorting segregation in their favor. Here, we identify and characterize in the model fungus Podospora anserina Spok1 and Spok2, two MDs known as Spore Killers. We show that they are related genes with both spore-killing distorter and spore-protecting responder activities carried out by the same allele. These alleles act as autonomous elements, exert their effects independently of their location in the genome and can act as MDs in other fungi. Additionally, Spok1 acts as a resistance factor to Spok2 killing. Genetical data and cytological analysis of Spok1 and Spok2 localization during the killing process suggest a complex mode of action for Spok proteins. Spok1 and Spok2 belong to a multigene family prevalent in the genomes of many ascomycetes. As they have no obvious cellular role, Spok1 and Spok2 Spore Killer genes represent a novel kind of selfish genetic elements prevalent in fungal genome that proliferate through meiotic distortion.

  12. Veil: A Wall of Segregation

    Directory of Open Access Journals (Sweden)

    Tayebeh Nowrouzi

    2015-08-01

    Full Text Available Moving behind the confines of the race has been the continuous efforts of African-Americans so as to reveal and confirm their true humanity and abilities to white race as well as their own race. African-Americans, Dubois posited, are shut out of the white America, inhabiting behind a vast veil which creates a deep division between the races. Veil is made of the fabric of racism interwoven thread by thread and imposed by white world. It is thrown discourteously and forcibly to the African-Americans whom their distorted images are imposed on them and their true humanity and identity are hidden behind the veil. This study overtakes to present how Loraine Hansberry, in her first and the most outstanding drama, A Raisin in the Sun examines the world within the veil. She demonstrated that Duboisian metaphoric veil is operating in the racist American society so that not only African-Americans are segregated physically and psychologically from the rest of the world but also are inflicted with obscurity of vision that are neither able to see themselves clearly nor be seen truly. On the other hand, it presents how the veil provides blacks with the second sight to observe and comprehend the racist nature of whites which is hidden and incomprehensible for them.

  13. High School Graduate Participation Rates: Proportions of Sacramento Area High School Graduates Enrolled in Los Rios Community College District, Fall 1998-Fall 1994.

    Science.gov (United States)

    Los Rios Community Coll. District, Sacramento, CA. Office of Planning and Research.

    This report profiles the enrollment patterns of recent high school graduates of the Greater Sacramento Metropolitan Area who attend Los Rios colleges (California). This summary and the full data report provide the District and its colleges with research information on rates of participation by students who graduated from Los Rios Community College…

  14. How different contexts of social capital are associated with self-rated health among Lithuanian high-school students.

    Science.gov (United States)

    Novak, Dario; Emeljanovas, Arunas; Mieziene, Brigita; Štefan, Lovro; Kawachi, Ichiro

    2018-01-01

    Adolescents' self-rated health is related to a number of sociodemographic and socio-economic factors, health-related behaviors, and their social environment. The impact of the latter is still not well explored. An adolescent's social environment is represented by the social capital, i.e. social resources that they can access. The relationships between various contexts of social capital (family, neighborhood, peers, and school) and self-rated health among adolescents are still unclear. This study aims to examine the relationships between various social capital contexts and self-rated health in Lithuanian adolescents. The current cross-sectional study includes a nationally representative sample of 1863 adolescents (51.4% were girls) aged 14-18 years. The indicators of self-rated health as well as indicators of social capital in family, neighborhood, and school contexts were assessed. The results of the relationships between self-rated health and contexts of social capital were calculated controlling for the following covariates: physical activity, psychological distress, gender, body mass index, and family socioeconomic status. Results indicate that there are significant relationships between good self-rated health and a higher level of family support, neighborhood trust, and vertical school trust. In the final logistic regression model, while controlling for all covariates, a higher level of family support and neighborhood trust remain significant predictors of good self-rated health. Family support and neighborhood trust are important correlates of self-rated health in adolescents.

  15. Mechanical Properties of Weakly Segregated Block Copolymers. 3. Influence of Strain Rate and Temperature on Tensile Properties of Poly(styrene-b-butyl methacrylate) Diblock Copolymers with Different Morphologies

    NARCIS (Netherlands)

    Weidisch, R.; Stamm, M.; Michler, G.H.; Fischer, H.R.; Jérôme, R.

    1999-01-01

    Poly(styrene-b-butyl methacrylate) diblock copolymers, PS-6-PBMA, with different morphologies are investigated with respect to the influence of strain rate and temperature on tensile properties. In the first part the mechanical properties of bicontinuous and perforated lamellar structure are

  16. Granular Segregation by an Oscillating Ratchet Mechanism

    International Nuclear Information System (INIS)

    Igarashi, A.; Horiuchi, Ch.

    2004-01-01

    We report on a method to segregate granular mixtures which consist of two kinds of particles by an oscillating ''ratchet'' mechanism. The segregation system has an asymmetrical sawtooth-shaped base which is vertically oscillating. Such a ratchet base produces a directional current of particles owing to its transport property. It is a counterintuitive and interesting phenomenon that a vertically vibrated base transports particles horizontally. This system is studied with numerical simulations, and it is found that we can apply such a system to segregation of mixtures of particles with different properties (radius or mass). Furthermore, we find out that an appropriate inclination of the ratchet-base makes the quality of segregation high. (author)

  17. School Board Leadership and Policymaking in Changing Political Environments

    Science.gov (United States)

    Frankenberg, Erica; Diem, Sarah

    2013-01-01

    As the demographic make-up of public schools (and neighborhoods) shift and schools become increasingly segregated, the role of school boards becomes critically important in maintaining policies designed to remedy segregation and promote equal opportunity, policies which may challenge the status quo. Specifically, in school districts and…

  18. Solute grain boundary segregation during high temperature plastic deformation in a Cr-Mo low alloy steel

    International Nuclear Information System (INIS)

    Chen, X.-M.; Song, S.-H.; Weng, L.-Q.; Liu, S.-J.

    2011-01-01

    Highlights: → The segregation of P and Mo is evidently enhanced by plastic deformation. → The boundary concentrations of P and Mo increase with increasing strain. → A model with consideration of site competition in grain boundary segregation in a ternary system is developed. → Model predictions show a reasonable agreement with the observations. - Abstract: Grain boundary segregation of Cr, Mo and P to austenite grain boundaries in a P-doped 1Cr0.5Mo steel is examined using field emission gun scanning transmission electron microscopy for the specimens undeformed and deformed by 10% with a strain rate of 2 x 10 -3 s -1 at 900 deg. C, and subsequently water quenched to room temperature. Before deformation, there is some segregation for Mo and P, but the segregation is considerably increased after deformation. The segregation of Cr is very small and there is no apparent difference between the undeformed and deformed specimens. Since the thermal equilibrium segregation has been attained prior to deformation, the segregation produced during deformation has a non-equilibrium characteristic. A theoretical model with consideration of site competition in grain boundary segregation between two solutes in a ternary alloy is developed to explain the experimental results. Model predictions are made, which show a reasonable agreement with the observations.

  19. Gender Differences in the Effect of Residential Segregation on Workplace Segregation among Newly Arrived Immigrants

    OpenAIRE

    Tammaru, Tiit; Strömgren, Magnus; van Ham, Maarten; Danzer, Alexander M.

    2015-01-01

    Contemporary cities are becoming more and more diverse in population as a result of immigration. Research also shows that within cities residential neighborhoods are becoming ethnically more diverse, but that residential segregation has remained persistently high. High levels of segregation are often seen as negative, preventing integration of immigrants in their host society and having a negative impact on people's lives. Segregation research often focuses on residential neighborhoods, but i...

  20. Children's social capital in the segregated context of Amsterdam: an historical-geographical approach

    NARCIS (Netherlands)

    Karsten, L.

    2011-01-01

    This paper addresses children’s social capital across space and over time. Empirical evidence comes from an in-depth study of changes in children’s daily lives in Amsterdam over the past 50 years. Different dimensions of religious and ethnic segregation at school and in the neighbourhood have

  1. Racial Segregation Patterns in Selective Universities. CEP Discussion Paper No. 1219

    Science.gov (United States)

    Arcidiacono, Peter; Aucejo, Esteban; Hussey, Andrew; Spenner, Kenneth

    2013-01-01

    This paper examines sorting into interracial friendships at selective universities. We show significant friendship segregation, particularly for blacks. Indeed, black friendships are no more diverse in college than in high school despite the colleges blacks attend having substantially smaller black populations. We show that part of the reason for…

  2. Gender Segregation in the Retail Industry

    OpenAIRE

    Lynch, Samantha

    2002-01-01

    This paper examines the phenomenon of occupational gender segregation in the retail industry, with a particular focus on part time working. The empirical data was gathered through a series of 59 interviews, and a small survey of employees, with store level managers in three UK retail organisations. The paper illustrates the extent of occupational gender segregation and considers the impact of such stereotyping on the gender pay gap, training and career development.\\ud \\ud Occupational gender ...

  3. The acoustic and perceptual cues affecting melody segregation for listeners with a cochlear implant.

    Directory of Open Access Journals (Sweden)

    Jeremy eMarozeau

    2013-11-01

    Full Text Available Our ability to listen selectively to single sound sources in complex auditory environments is termed ‘auditory stream segregation.’ This ability is affected by peripheral disorders such as hearing loss, as well as plasticity in central processing such as occurs with musical training. Brain plasticity induced by musical training can enhance the ability to segregate sound, leading to improvements in a variety of auditory abilities. The melody segregation ability of 12 cochlear-implant recipients was tested using a new method to determine the perceptual distance needed to segregate a simple 4-note melody from a background of interleaved random-pitch distractor notes. In experiment 1, participants rated the difficulty of segregating the melody from distracter notes. Four physical properties of the distracter notes were changed. In experiment 2, listeners were asked to rate the dissimilarity between melody patterns whose notes differed on the four physical properties simultaneously. Multidimensional scaling analysis transformed the dissimilarity ratings into perceptual distances. Regression between physical and perceptual cues then derived the minimal perceptual distance needed to segregate the melody.The most efficient streaming cue for CI users was loudness. For the normal hearing listeners without musical backgrounds, a greater difference on the perceptual dimension correlated to the temporal envelope is needed for stream segregation in CI users. No differences in streaming efficiency were found between the perceptual dimensions linked to the F0 and the spectral envelope.Combined with our previous results in normally-hearing musicians and non-musicians, the results show that differences in training as well as differences in peripheral auditory processing (hearing impairment and the use of a hearing device influences the way that listeners use different acoustic cues for segregating interleaved musical streams.

  4. New segregation analysis of panic disorder

    Energy Technology Data Exchange (ETDEWEB)

    Vieland, V.J.; Fyer, A.J.; Chapman, T. [Columbia Univ., New York, NY (United States)] [and others

    1996-04-09

    We performed simple segregation analyses of panic disorder using 126 families of probands with DSM-III-R panic disorder who were ascertained for a family study of anxiety disorders at an anxiety disorders research clinic. We present parameter estimates for dominant, recessive, and arbitrary single major locus models without sex effects, as well as for a nongenetic transmission model, and compare these models to each other and to models obtained by other investigators. We rejected the nongenetic transmission model when comparing it to the recessive model. Consistent with some previous reports, we find comparable support for dominant and recessive models, and in both cases estimate nonzero phenocopy rates. The effect of restricting the analysis to families of probands without any lifetime history of comorbid major depression (MDD) was also examined. No notable differences in parameter estimates were found in that subsample, although the power of that analysis was low. Consistency between the findings in our sample and in another independently collected sample suggests the possibility of pooling such samples in the future in order to achieve the necessary power for more complex analyses. 32 refs., 4 tabs.

  5. Schistosomes infection rate in relation to environmental factors in school children.

    Science.gov (United States)

    Raja'a, Y A; Assiragi, H M; Abu-Luhom, A A; Mohammed, A B; Albahr, M H; Ashaddadi, M A; Al Muflihi, A N

    2000-07-01

    An epidemiological comparative survey aimed at determination of prevalence and focal distribution of Schistosomes infection and intestinal parasites to provide a reference for evaluating the need for community intervention. All children of 14th October Primary School were involved. The children were from 7 villages that lie on the Assahul valley of lbb governorates in Yemen. The total number was 230 with (82%) boys and (18%) girls. Their age was between 5-18 years with a mean of 10.24 +/- 2.6 years. Millipore and modified Kato techniques were adopted to quantify urinary and intestinal Schistosomes eggs. Other ova, larvae, cysts were recorded whenever seen. It was revealed that there was a Schistosomes infection rate of 37%. The mansoni prevalence was 35%, hematobia was 5% and mixed infections were 3%. Light infection was classified among 17% of all children; moderate infection among 18% and no intense mansoni infection was determined. Whereas in the case of hematobia species, 2% were intense and 3% were light. Intensity in all children was 5% eggs/g feces in case of intestinal bilharzia and 1% egg/10 ml urine in case of urinary. With regard to the prevalence of any soil-transmitted parasites, it was found to be 69% (Ascariosis 68%, Trichuriosis 10%). Double infection was found in 10%. Hookworm eggs were not seen. Infection rates with other parasites were as follows: Giardiosis 18%, Amoebiosis 14%, ova of Hymenolepes nana were seen in 13%, Taeniosis affected 13% and E. Vermicularis 1%. Bivariate analysis revealed significant associations between Schistosomes infection with residence near the valley, male sex and frequent water contact activities. No significant association was found with the age of the child, parents' education, availability of latrine or household standpipe water. In conclusion, schistosomosis was moderate, whereas soil transmitted helminthosis were intense.

  6. Gender Segregation in the Spanish Labor Market: An Alternative Approach

    Science.gov (United States)

    del Rio, Coral; Alonso-Villar, Olga

    2010-01-01

    The aim of this paper is to study occupational segregation by gender in Spain, which is a country where occupational segregation explains a large part of the gender wage gap. As opposed to previous studies, this paper measures not only overall segregation, but also the segregation of several population subgroups. For this purpose, this paper uses…

  7. Racial Discipline Disproportionality in Montessori and Traditional Public Schools: A Comparative Study Using the Relative Rate Index

    Science.gov (United States)

    Brown, Katie E.; Steele, Aimy S. L.

    2015-01-01

    Research from the past 40 years indicates that Black students in primary and secondary school settings are subjected to exclusionary discipline, including suspension and expulsion, at rates two to three times higher than their White peers (Children's Defense Fund, 1975; Skiba, Michael, Nardo, & Peterson, 2002). Although this phenomenon has…

  8. The Effect of Poverty, Gender Exclusion, and Child Labor on Out-of-School Rates for Female Children

    Science.gov (United States)

    Laborda Castillo, Leopoldo; Sotelsek Salem, Daniel; Sarr, Leopold Remi

    2014-01-01

    In this article, the authors analyze the effect of poverty, social exclusion, and child labor on out-of-school rates for female children. This empirical study is based on a dynamic panel model for a sample of 216 countries over the period 1970 to 2010. Results based on the generalized method of moments (GMM) of Arellano and Bond (1991) and the…

  9. Dose dependence of radiation-induced segregation in Ni-1 at% Si

    International Nuclear Information System (INIS)

    Rehn, L.E.; Okamoto, P.R.; Wiedersich, H.

    1979-01-01

    Measurements have been made of alloy composition as a function of depth from the external surface in Ni-1 at% Si specimens after irradiation with 3-MeV 58 Ni + ions to several different doses at nominal temperatures of 525 and 600 0 C. Very rapid segregation of Si toward the external surface ocurred during irradiation. Surface concentrations of Si in excess of the 10 at% solubility limit were found at both irradiation temperatures after a dose of only approximately 0.05 dpa. The rate of segregation decreased markedly in the dose range from approximately 1-10 dpa. Qualitative agreement was found between the experimental observations and calculations made using a modified Johnson-Lam segregation mode (1976). The present investigation suggests that radiation-induced segregation may significantly alter the mechanical behavior of irradiated alloys long before the onset of void swelling. (Auth.)

  10. Anglo-Saxon Ideologies in the 1920s-1930s: Their Impact on the Segregation of Mexican Students in California.

    Science.gov (United States)

    Menchaca, Martha; Valencia, Richard R.

    1990-01-01

    Traces the development of Anglo-Saxon superiority theories from the nineteenth century onward and demonstrates their impact on social conditions in the southwest, specifically on school segregation in Santa Paula School District (California) from the 1920s to the present. (DM)

  11. Effects of Intradistrict School Mobility and High Student Turnover Rates on Early Reading Achievement

    Science.gov (United States)

    LeBoeuf, Whitney A.; Fantuzzo, John W.

    2018-01-01

    The primary aim of this study was to assess the relations between concurrent, cumulative, and contextual intradistrict school mobility and early reading achievement. Longitudinal administrative school records were used for an entire cohort of students in a large urban district from first through third grade. Findings indicated that students with a…

  12. Principals' Leadership Practices and Mathematics Pass Rate in Jamaican High Schools

    Science.gov (United States)

    Palmer, David; Hermond, Douglas; Gardiner, Carl

    2014-01-01

    This research was intended to explore the degree to which leadership practices impacted Jamaican schools' mathematics achievement. More specifically, the researchers examined Jamaica's high school students' CSEC mathematics performance in relation to principals' instructional leadership behaviors as measured by teachers' perceptions, using Kouzes…

  13. High School Leaders' Perceptions of Practices That Increase Graduation Rates of African American Males

    Science.gov (United States)

    Jones, Linda D.

    2015-01-01

    Research indicates there are significant differences in the academic performance of minorities and whites, particularly at the high school level. On average, Latino and African American high school students read and perform math on the same level as 13-year-old white students and trail their white peers by an average of 20 test points on math and…

  14. Progress Is No Accident: Why ESEA Can't Backtrack on High School Graduation Rates

    Science.gov (United States)

    Alliance for Excellent Education, 2015

    2015-01-01

    In conjunction with the White House Next Gen High School Summit on November 10, a new report finds that the number of high school dropouts decreased from 1 million in 2008 to approximately 750,000 in 2012. The report, released by the Alliance for Excellent Education, America's Promise Alliance, Civic Enterprises, and Everyone Graduates Center,…

  15. May new school models minimize status of drop-out rates?

    DEFF Research Database (Denmark)

    Andersen, Frans Ørsted; Petersen, Karen Bjerg

    Conference paper on studies of the American P-tech schools that have good results lifting ghetto kids out of poverty and establishing a STEM career from them.......Conference paper on studies of the American P-tech schools that have good results lifting ghetto kids out of poverty and establishing a STEM career from them....

  16. African American Educators' Ideas and Practices for Increasing High School Graduation Rates, 1920-1940

    Science.gov (United States)

    Juergensen, Miyoshi B.

    2015-01-01

    This study explores African American educators' ideas about school completion in the 1920s and 1930s as a way to begin to understand their contributions to the historical discourse on school completion. Using publications from African American professional teaching organizations, the author elevates and examines how African American educators both…

  17. The Impact of Collective Bargaining on Teacher Transfer Rates in Urban High-Poverty Schools

    Science.gov (United States)

    Nelson, F. Howard

    2006-01-01

    Data in this report reveals that collectively bargaining agreements are not the source of the teacher quality problem in urban school districts. The data shows that collective bargaining agreements are associated with reduced teacher transfer activity, especially in high-poverty schools, and less reliance on first-year teachers to staff…

  18. Radiation induced segregation and point defects in binary copper alloys

    International Nuclear Information System (INIS)

    Monteiro, W.A.

    1984-01-01

    Considerable progress, both theoretical and experimental, has been made in establishing and understanding the influence of factors such as temperature, time, displacement rate dependence and the effect of initial solute misfit on radiation induced solute diffusion and segregation. During irradiation, the composition of the alloy changes locally, due to defect flux driven non-equilibrium segregation near sinks such as voids, external surfaces and grain boundaries. This change in composition could influence properties and phenomena such as ductility, corrosion resistance, stress corrosion cracking, sputtering and blistering of materials used in thermo-nuclear reactors. In this work, the effect of 1 MeV electron irradiation on the initiation and development of segregation and defect diffusion in binary copper alloys has been studied in situ, with the aid of a high voltage electron microscope. The binary copper alloys had Be, Pt and Sn as alloying elements which had atomic radii less than, similar and greater than that of copper, respectively. It has been observed that in a wide irradiation temperature range, stabilization and growth of dislocation loops took place in Cu-Sn and Cu-Pt alloys. Whereas in the Cu-Be alloy, radiation induced precipitates formed and transformed to the stable γ phase. (Author) [pt

  19. Energy Expenditure in Playground Games in Primary School Children Measured by Accelerometer and Heart Rate Monitors.

    Science.gov (United States)

    García-Prieto, Jorge Cañete; Martinez-Vizcaino, Vicente; García-Hermoso, Antonio; Sánchez-López, Mairena; Arias-Palencia, Natalia; Fonseca, Juan Fernando Ortega; Mora-Rodriguez, Ricardo

    2017-10-01

    The aim of this study was to examine the energy expenditure (EE) measured using indirect calorimetry (IC) during playground games and to assess the validity of heart rate (HR) and accelerometry counts as indirect indicators of EE in children´s physical activity games. 32 primary school children (9.9 ± 0.6 years old, 19.8 ± 4.9 kg · m -2 BMI and 37.6 ± 7.2 ml · kg -1 · min -1 VO 2max ). Indirect calorimetry (IC), accelerometry and HR data were simultaneously collected for each child during a 90 min session of 30 playground games. Thirty-eight sessions were recorded in 32 different children. Each game was recorded at least in three occasions in other three children. The intersubject coefficient of variation within a game was 27% for IC, 37% for accelerometry and 13% for HR. The overall mean EE in the games was 4.2 ± 1.4 kcals · min -1 per game, totaling to 375 ± 122 kcals/per 90 min/session. The correlation coefficient between indirect calorimetry and accelerometer counts was 0.48 (p = .026) for endurance games and 0.21 (p = .574) for strength games. The correlation coefficient between indirect calorimetry and HR was 0.71 (p = .032) for endurance games and 0.48 (p = .026) for strength games. Our data indicate that both accelerometer and HR monitors are useful devices for estimating EE during endurance games, but only HR monitors estimates are accurate for endurance games.

  20. [Class Climate, Academic Well-Being and Self-Rated Health Among School Children in Germany: Findings of the National Educational Panel Study (NEPS)].

    Science.gov (United States)

    Rathmann, Katharina; Herke, Max; Hurrelmann, Klaus; Richter, Matthias

    2018-04-01

    The aim of this study was to examine the associations between features of class climate and school wellbeing, based on self-rated health and reports of absence from school due to illness among adolescents in secondary schools, by using data from the German National Educational Panel Study (NEPS). Data was obtained from the National Educational Panel Study (NEPS). The sample includes (n=7,348) seventh grade students in regular schools (Starting Cohort 3, Wave 3, 2012). Measures of class climate comprise indicators about demands, control and orientation, autonomy and interaction among students as well as teaching quality in German language class. School wellbeing was measured by satisfaction with school and helplessness in main school subjects. Bivariate and logistic multilevel logistic regression techniques are applied, by controlling for student age, gender and school type attended. Multilevel results showed that particularly among students with higher school satisfaction, there was a higher likelihood of self-rated health and less school absence due to illness. In contrast, perceived helplessness in major subjects and learning orientation were negatively associated with both outcomes. Further, students attending low track schools had a higher risk of school absence than students in high track schools. The results highlight the fact that particularly students' school wellbeing in terms of school satisfaction and perceived helplessness in the subjects German and mathematics are associated with self-rated poorer health and school absence due to illness. Therefore, health promotion initiatives should particularly focus on students' school wellbeing as well as on students attending low track schools. © Georg Thieme Verlag KG Stuttgart · New York.

  1. How different contexts of social capital are associated with self-rated health among Lithuanian high-school students

    Science.gov (United States)

    Novak, Dario; Emeljanovas, Arunas; Mieziene, Brigita; Štefan, Lovro; Kawachi, Ichiro

    2018-01-01

    ABSTRACT Background. Adolescents’ self-rated health is related to a number of sociodemographic and socio-economic factors, health-related behaviors, and their social environment. The impact of the latter is still not well explored. An adolescent’s social environment is represented by the social capital, i.e. social resources that they can access. The relationships between various contexts of social capital (family, neighborhood, peers, and school) and self-rated health among adolescents are still unclear. Objective. This study aims to examine the relationships between various social capital contexts and self-rated health in Lithuanian adolescents. Methods. The current cross-sectional study includes a nationally representative sample of 1863 adolescents (51.4% were girls) aged 14–18 years. The indicators of self-rated health as well as indicators of social capital in family, neighborhood, and school contexts were assessed. The results of the relationships between self-rated health and contexts of social capital were calculated controlling for the following covariates: physical activity, psychological distress, gender, body mass index, and family socioeconomic status. Results. Results indicate that there are significant relationships between good self-rated health and a higher level of family support, neighborhood trust, and vertical school trust. In the final logistic regression model, while controlling for all covariates, a higher level of family support and neighborhood trust remain significant predictors of good self-rated health. Conclusions. Family support and neighborhood trust are important correlates of self-rated health in adolescents. PMID:29871556

  2. Roosevelt elk density and social segregation: Foraging behavior and females avoiding larger groups of males

    Science.gov (United States)

    Weckerly, F.; McFarland, K.; Ricca, M.; Meyer, K.

    2004-01-01

    Intersexual social segregation at small spatial scales is prevalent in ruminants that are sexually dimorphic in body size. Explaining social segregation, however, from hypotheses of how intersexual size differences affects the foraging process of males and females has had mixed results. We studied whether body size influences on forage behavior, intersexual social incompatibility or both might influence social segregation in a population of Roosevelt elk (Cervus elaphus roosevelt) that declined 40% over 5 y. Most males and females in the population occurred in the same forage patches, meadows, but occupied different parts of meadows and most groups were overwhelming comprised of one sex. The extent of segregation varied slightly with changing elk density. Cropping rate, our surrogate of forage ingestion, of males in mixed-sex groups differed from males in male-only groups at high, but not low, elk density. In a prior study of intersexual social interactions it was shown that females avoided groups containing ???6 males. Therefore, we predicted that females should avoid parts of meadows where groups of males ???6 were prevalent. Across the 5 y of study this prediction held because ???5% of all females were found in parts of meadows where median aggregation sizes of males were ???6. Social segregation was coupled to body size influences on forage ingestion at high density and social incompatibility was coupled to social segregation regardless of elk density.

  3. Sound stream segregation: a neuromorphic approach to solve the "cocktail party problem" in real-time.

    Science.gov (United States)

    Thakur, Chetan Singh; Wang, Runchun M; Afshar, Saeed; Hamilton, Tara J; Tapson, Jonathan C; Shamma, Shihab A; van Schaik, André

    2015-01-01

    The human auditory system has the ability to segregate complex auditory scenes into a foreground component and a background, allowing us to listen to specific speech sounds from a mixture of sounds. Selective attention plays a crucial role in this process, colloquially known as the "cocktail party effect." It has not been possible to build a machine that can emulate this human ability in real-time. Here, we have developed a framework for the implementation of a neuromorphic sound segregation algorithm in a Field Programmable Gate Array (FPGA). This algorithm is based on the principles of temporal coherence and uses an attention signal to separate a target sound stream from background noise. Temporal coherence implies that auditory features belonging to the same sound source are coherently modulated and evoke highly correlated neural response patterns. The basis for this form of sound segregation is that responses from pairs of channels that are strongly positively correlated belong to the same stream, while channels that are uncorrelated or anti-correlated belong to different streams. In our framework, we have used a neuromorphic cochlea as a frontend sound analyser to extract spatial information of the sound input, which then passes through band pass filters that extract the sound envelope at various modulation rates. Further stages include feature extraction and mask generation, which is finally used to reconstruct the targeted sound. Using sample tonal and speech mixtures, we show that our FPGA architecture is able to segregate sound sources in real-time. The accuracy of segregation is indicated by the high signal-to-noise ratio (SNR) of the segregated stream (90, 77, and 55 dB for simple tone, complex tone, and speech, respectively) as compared to the SNR of the mixture waveform (0 dB). This system may be easily extended for the segregation of complex speech signals, and may thus find various applications in electronic devices such as for sound segregation and

  4. Towards deep learning with segregated dendrites.

    Science.gov (United States)

    Guerguiev, Jordan; Lillicrap, Timothy P; Richards, Blake A

    2017-12-05

    Deep learning has led to significant advances in artificial intelligence, in part, by adopting strategies motivated by neurophysiology. However, it is unclear whether deep learning could occur in the real brain. Here, we show that a deep learning algorithm that utilizes multi-compartment neurons might help us to understand how the neocortex optimizes cost functions. Like neocortical pyramidal neurons, neurons in our model receive sensory information and higher-order feedback in electrotonically segregated compartments. Thanks to this segregation, neurons in different layers of the network can coordinate synaptic weight updates. As a result, the network learns to categorize images better than a single layer network. Furthermore, we show that our algorithm takes advantage of multilayer architectures to identify useful higher-order representations-the hallmark of deep learning. This work demonstrates that deep learning can be achieved using segregated dendritic compartments, which may help to explain the morphology of neocortical pyramidal neurons.

  5. An equivalence study of interview platform: Does videoconference technology impact medical school acceptance rates of different groups?

    Science.gov (United States)

    Ballejos, Marlene P; Oglesbee, Scott; Hettema, Jennifer; Sapien, Robert

    2018-02-14

    Web-based interviewing may be an effective element of a medical school's larger approach to promotion of holistic review, as recommended by the Association of American Medical Colleges, by facilitating the feasibility of including rural and community physicians in the interview process. Only 10% of medical schools offer videoconference interviews to applicants and little is known about the impact of this interview modality on the admissions process. This study investigated the impact of overall acceptance rates using videoconference interviews and face-to-face interviews in the medical school selection process using an equivalence trial design. The University of New Mexico School of Medicine integrated a videoconferencing interview option for community and rural physician interviewers in a pseudo-random fashion during the 2014-2016 admissions cycles. Logistic regression was conducted to examine whether videoconference interviews impacted acceptance rates or the characteristics of accepted students. Demographic, admissions and diversity factors were analyzed that included applicant age, MCAT score, cumulative GPA, gender, underrepresented in medicine, socioeconomic status and geographic residency. Data from 752 interviews were analyzed. Adjusted rates of acceptance for face-to-face (37.0%; 95% CI 28.2, 46.7%) and videoconference (36.1%; 95% CI 17.8, 59.5%) interviews were within an a priori ± 5% margin of equivalence. Both interview conditions yielded highly diverse groups of admitted students. Having a higher medical college admission test score, grade point average, and self-identifying as disadvantaged increased odds of admission in both interview modalities. Integration of the videoconference interview did not impact the overall acceptance of a highly diverse and qualified group of applicants, and allowed rural and community physicians to participate in the medical school interview process as well as allowed campus faculty and medical student committee members

  6. Comparison of Indiana High School Football Injury Rates by Inclusion of the USA Football "Heads Up Football" Player Safety Coach.

    Science.gov (United States)

    Kerr, Zachary Y; Dalton, Sara L; Roos, Karen G; Djoko, Aristarque; Phelps, Jennifer; Dompier, Thomas P

    2016-05-01

    In Indiana, high school football coaches are required to complete a coaching education course with material related to concussion awareness, equipment fitting, heat emergency preparedness, and proper technique. Some high schools have also opted to implement a player safety coach (PSC). The PSC, an integral component of USA Football's Heads Up Football (HUF) program, is a coach whose primary responsibility is to ensure that other coaches are implementing proper tackling and blocking techniques alongside other components of the HUF program. To compare injury rates in Indiana high school football teams by their usage of a PSC or online coaching education only. Cohort study; Level of evidence, 2. Athletic trainers (ATs) evaluated and tracked injuries at each practice and game during the 2015 high school football season. Players were drawn from 6 teams in Indiana. The PSC group, which used the PSC component, was comprised of 204 players from 3 teams. The "education only" group (EDU), which utilized coaching education only, was composed of 186 players from 3 teams. Injury rates and injury rate ratios (IRRs) were reported with 95% confidence intervals (CIs). During 25,938 athlete-exposures (AEs), a total of 149 injuries were reported, of which 54 (36.2%) and 95 (63.8%) originated from the PSC and EDU groups, respectively. The practice injury rate was lower in the PSC group than the EDU group (2.99 vs 4.83/1000 AEs; IRR, 0.62; 95% CI, 0.40-0.95). The game injury rate was also lower in the PSC group than the EDU group (11.37 vs 26.37/1000 AEs; IRR, 0.43; 95% CI, 0.25-0.74). When restricted to concussions only, the rate was lower in the PSC group (0.09 vs 0.73/1000 AEs; IRR, 0.12; 95% CI, 0.01-0.94), although only 1 concussion was reported in the PSC group. No differences were found in game concussion rates (0.60 vs 4.39/1000 AEs; IRR, 0.14; 95% CI, 0.02-1.11). Findings support the PSC as an effective method of injury mitigation in high school football. Future research

  7. Prevalence of parent-rated attention deficit hyperactivity disorder and associated parent-related factors in primary school children of Navi Mumbai--a school based study.

    Science.gov (United States)

    Ajinkya, Shaunak; Kaur, Darpan; Gursale, Akshay; Jadhav, Pradeep

    2013-03-01

    To study the prevalence of parent-rated attention deficit hyperactivity disorder and associated parent-related factors in primary school children of Navi Mumbai. One hundred twenty two children including both boys and girls aged between 6 y and 11 y were selected from a school at Navi Mumbai and their parents were given the National Innovative for Children's Healthcare Quality (NICHQ) Vanderbilt Assessment Scale to be filled and returned, which was subsequently analyzed using SPSS (version 16). The prevalence of attention deficit hyperactivity disorder was 12.3 % with boy to girl ratio of 3:2. It was more prevalent in nuclear type of family and in families where a single parent was working especially where the father was the sole breadwinner and doing semi-skilled or unskilled type of work. No significant relation was found between the numbers of work-related hours when parents were away from children and attention deficit hyperactivity disorder. Attention deficit hyperactivity disorder is prevalent in the primary school-going population of Navi Mumbai, especially in boys. The increased prevalence in nuclear families and families with single working parent should further be explored. Further studies with larger sample size and longer period of follow up may be recommended. The study also recommends screening of school children for symptoms of attention deficit hyperactivity disorder (ADHD) for early diagnosis and treatment.

  8. Chemical segregation and self polarisation in ferroelectrics

    Directory of Open Access Journals (Sweden)

    Bernard E. Watts

    2009-06-01

    Full Text Available Chemical partitioning or segregation is commonly encountered in solid-state syntheses. It is driven by compositional, thermal and electric field gradients. These phenomena can be quite extreme in thin films and lead to notable effects on the electrical properties of ferroelectrics. The segregation in ferroelectric thin films will be illustrated and the mechanisms explained in terms of diffusion processes driven by a potential gradient of the oxygen. The hypothesis can also explain self polarisation and imprint in ferroelectric hysteresis.

  9. Particle segregation in pneumatic conveying lines

    Energy Technology Data Exchange (ETDEWEB)

    McGlinchey, D.; Marjanovic, P.; Cook, S.; Jones, M.G. [Glasgow Caledonian University, Glasgow (United Kingdom). Centre for Industrial Bulk Solids Handling

    2000-07-01

    This investigation studied segregation of particles during pneumatic transport from a theoretical and experimental perspective. Dilute phase or suspension flow and dense phase (non-suspension flow) were both considered. A computer model was generated based on the conservation equations to investigate dilute phase conditions; an initial qualitative investigation of material behaviour being conveyed in dense phase was made with plastic pellets and salt as a segregating mixture in a small test rig and the results from a full scale test rig conveying two grades of coal of different size distributions are discussed. 11 refs., 9 figs., 1 tab.

  10. Kinetics of monolayer graphene growth by segregation on Pd(111)

    Energy Technology Data Exchange (ETDEWEB)

    Mok, H. S.; Murata, Y.; Kodambaka, S., E-mail: kodambaka@ucla.edu [Department of Materials Science and Engineering, University of California Los Angeles, Los Angeles, California 90095 (United States); Ebnonnasir, A.; Ciobanu, C. V. [Department of Mechanical Engineering and Materials Science Program, Colorado School of Mines, Golden, Colorado 80401 (United States); Nie, S.; McCarty, K. F. [Sandia National Laboratories, Livermore, California 94550 (United States)

    2014-03-10

    Using in situ low-energy electron microscopy and density functional theory calculations, we follow the growth of monolayer graphene on Pd(111) via surface segregation of bulk-dissolved carbon. Upon lowering the substrate temperature, nucleation of graphene begins on graphene-free Pd surface and continues to occur during graphene growth. Measurements of graphene growth rates and Pd surface work functions establish that this continued nucleation is due to increasing C adatom concentration on the Pd surface with time. We attribute this anomalous phenomenon to a large barrier for attachment of C adatoms to graphene coupled with a strong binding of the non-graphitic C to the Pd surface.

  11. Kinetics of monolayer graphene growth by segregation on Pd(111)

    International Nuclear Information System (INIS)

    Mok, H. S.; Murata, Y.; Kodambaka, S.; Ebnonnasir, A.; Ciobanu, C. V.; Nie, S.; McCarty, K. F.

    2014-01-01

    Using in situ low-energy electron microscopy and density functional theory calculations, we follow the growth of monolayer graphene on Pd(111) via surface segregation of bulk-dissolved carbon. Upon lowering the substrate temperature, nucleation of graphene begins on graphene-free Pd surface and continues to occur during graphene growth. Measurements of graphene growth rates and Pd surface work functions establish that this continued nucleation is due to increasing C adatom concentration on the Pd surface with time. We attribute this anomalous phenomenon to a large barrier for attachment of C adatoms to graphene coupled with a strong binding of the non-graphitic C to the Pd surface

  12. Effects of zinc supplementation on parent and teacher behaviour rating scores in low socioeconomic level Turkish primary school children.

    Science.gov (United States)

    Uçkardeş, Yasemin; Ozmert, Elif N; Unal, Fatih; Yurdakök, Kadriye

    2009-04-01

    To determine the effect of zinc supplementation on behaviour in low-income school aged children. Double-blind randomized, placebo controlled trial. Low-income district primary school in Turkey. Third grade students in the school. Among 252 students, 226 participated and 218 completed the study. Children in each class were randomized either to the study group to receive 15 mg/day elemental zinc syrup or to placebo group to receive the syrup without zinc for 10 weeks. The change in Conner's Rating Scales for Teachers and Parents scores after supplementation. The mean Conner's Rating Scale for Parents scores on attention deficit, hyperactivity, oppositional behaviour and conduct disorder decreased significantly in the study and placebo groups after supplementation (p children with clinically significant parent ratings on attention deficit (p = 0.01) and hyperactivity (p = 0.004) decreased in the study group while prevalence of oppositional behaviour (p = 0.007) decreased in the placebo group. In children of mothers with low education all mean Parents' scores decreased significantly (p children with clinically significant scores for attention deficit, hyperactivity and oppositional behaviour decreased only in the study group (p children with clinically significant scores for attention deficit and hyperactivity. The affect on behaviour was more evident in the children of low educated mothers.

  13. Influence of the "surface effect" on the segregation parameters of S in Fe(100): A multi-scale modelling and Auger Electron Spectroscopy study

    Science.gov (United States)

    Barnard, P. E.; Terblans, J. J.; Swart, H. C.

    2015-12-01

    The article takes a new look at the process of atomic segregation by considering the influence of surface relaxation on the segregation parameters; the activation energy (Q), segregation energy (ΔG), interaction parameter (Ω) and the pre-exponential factor (D0). Computational modelling, namely Density Functional Theory (DFT) and the Modified Darken Model (MDM) in conjunction with Auger Electron Spectroscopy (AES) was utilized to study the variation of the segregation parameters for S in the surface region of Fe(100). Results indicate a variation in each of the segregation parameters as a function of the atomic layer under consideration. Values of the segregation parameters varied more dramatically as the surface layer is approached, with atomic layer 2 having the largest deviations in comparison to the bulk values. This atomic layer had the highest Q value and formed the rate limiting step for the segregation of S towards the Fe(100) surface. It was found that the segregation process is influenced by two sets of segregation parameters, those of the surface region formed by atomic layer 2, and those in the bulk material. This article is the first to conduct a full scale investigation on the influence of surface relaxation on segregation and labelled it the "surface effect".

  14. Engineering economic evaluations of trash segregation alternatives

    International Nuclear Information System (INIS)

    Collins, H.E.

    1987-01-01

    Health physicists are becoming increasingly involved in the selection of equipment to segregate a contaminated trash from clean trash in the effort to reduce low level waste disposal costs. Although well qualified to evaluate the technical merits of different equipment, health physicists also need to be aware of the elements of economic comparisons of different alternatives that meet all technical requirements

  15. Segregation reinforced by urban planning | IDRC - International ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2015-10-28

    Oct 28, 2015 ... ... What is driving urban violence? Segregated urban planning can leave a legacy of community tension and insecurity. Potential solutions? Include vulnerable communities in city planning decisions; invest in transport infrastructure; and regularly update city development plans to reflect population growth.

  16. 49 CFR 176.83 - Segregation.

    Science.gov (United States)

    2010-10-01

    ... presence of one or more steel bulkheads or decks between them or a combination thereof. Intervening spaces... substance but vary only in their water content (for example, sodium sulfide in Division 4.2 or Class 8) or... applied. (11) Certain exceptions from segregation for waste cyanides or waste cyanide mixtures or...

  17. Plasmid and chromosome segregation in prokaryotes

    DEFF Research Database (Denmark)

    Møller-Jensen, Jakob; Bugge Jensen, Rasmus; Gerdes, Kenn

    2000-01-01

    Recent major advances in the understanding of prokaryotic DNA segregation have been achieved by using fluorescence microscopy to visualize the localization of cellular components. Plasmids and bacterial chromosomes are partitioned in a highly dynamic fashion, suggesting the presence of a mitotic...

  18. A Social Network Analysis of Occupational Segregation

    DEFF Research Database (Denmark)

    Buhai, Ioan Sebastian; van der Leij, Marco

    We develop a social network model of occupational segregation between different social groups, generated by the existence of positive inbreeding bias among individuals from the same group. If network referrals are important for job search, then expected homophily in the contact network structure...

  19. A Public Relations Nightmare: ACLU Class Action Lawsuit Exposes Inaccurate and Inequitable High School Graduation Rates

    Science.gov (United States)

    Watson, Terri N.; Brown, Kathleen M.

    2010-01-01

    Florida's decision to equate a GED to a high school diploma undermines the attempt of No Child Left Behind to close the achievement gap, while infringing on the public's trust. Public trust fosters a culture of systemic equity and social justice, which are necessary for academic excellence (Byrk & Schneider, 2003). Florida's code of ethics for…

  20. Rates of Cyber Victimization and Bullying among Male Australian Primary and High School Students

    Science.gov (United States)

    Sakellariou, Tass; Carroll, Annemaree; Houghton, Stephen

    2012-01-01

    The prevalence and nature of electronic forms of bullying (cyberbullying) was investigated among 1,530 primary and secondary school aged male students (Years 6 to 12; 9-18 years, chronologically) in Sydney and Brisbane, Australia. Findings revealed that victimization via the Internet was the most common form of cyberbullying with 11.5 percent of…

  1. Effects of Music on Physical Activity Rates of Junior High School Physical Education Students

    Science.gov (United States)

    Brewer, Lindsey; Barney, David C.; Prusak, Keven A.; Pennington, Todd

    2016-01-01

    Music is an everyday occurrence in a person's life. Music is heard in the workplace, in homes, and in the mall. Music can also be heard as a person exercises. Therefore, the purpose of this study was to examine the effects of music on junior high students (n = 305) step counts and time in activity in junior high school physical education classes.…

  2. Review and Extension of CO2-Based Methods to Determine Ventilation Rates with Application to School Classrooms

    Directory of Open Access Journals (Sweden)

    Stuart Batterman

    2017-02-01

    Full Text Available The ventilation rate (VR is a key parameter affecting indoor environmental quality (IEQ and the energy consumption of buildings. This paper reviews the use of CO2 as a “natural” tracer gas for estimating VRs, focusing on applications in school classrooms. It provides details and guidance for the steady-state, build-up, decay and transient mass balance methods. An extension to the build-up method and an analysis of the post-exercise recovery period that can increase CO2 generation rates are presented. Measurements in four mechanically-ventilated school buildings demonstrate the methods and highlight issues affecting their applicability. VRs during the school day fell below recommended minimum levels, and VRs during evening and early morning were on the order of 0.1 h−1, reflecting shutdown of the ventilation systems. The transient mass balance method was the most flexible and advantageous method given the low air change rates and dynamic occupancy patterns observed in the classrooms. While the extension to the build-up method improved stability and consistency, the accuracy of this and the steady-state method may be limited. Decay-based methods did not reflect the VR during the school day due to heating, ventilation and air conditioning (HVAC system shutdown. Since the number of occupants in classrooms changes over the day, the VR expressed on a per person basis (e.g., L·s−1·person−1 depends on the occupancy metric. If occupancy measurements can be obtained, then the transient mass balance method likely will provide the most consistent and accurate results among the CO2-based methods. Improved VR measurements can benefit many applications, including research examining the linkage between ventilation and health.

  3. [Study on the detection rate and risk factors regarding non-suicidal self-injurious behavior in middle school students].

    Science.gov (United States)

    Yan, Jing; Zhu, Cui-zhen; Situ, Ming-jing; DU, Na; Huang, Yi

    2012-01-01

    To understand the prevalence and risk factors of non-suicidal self-injury in middle school students. 1312 middle school students of Pengzhou and Santai were selected to fill in a Risky Behavior Questionnaire for Adolescence (RBQ-A), Family Environment Scale (FES), Center for Epidemiological Survey, Depression Scale (CES-D), Adolescent Self-Rating Life Events Check List (ASLEC), Social Support Scale for Adolescents (SSSA) and self-administered questionnaire. In all the research subjects, 1288 were qualified for the study in April 2011 before the risk factors for non-suicidal self-injury were identified by logistic regression. In 1288 middle school students, 22.67% had a history of non-suicidal self-injury, with 22.70% in boys and 22.64% in girls. 63.36% of students had injured themselves through variously ways, more seen in boys (26.88%) than in girls (11.36%) who cut or burnt themselves. The scores of ASLEC and CES-D in non-suicidal self-injury group appeared higher than that in the control group and the score of SSSA was found higher in the control group. The main risk factors for non-suicidal self-injuries were family conflict, depressive emotion, negative life events and receiving less social support. The prevalence of non-suicidal self-injury among middle school students in Pengzhou was high, which called for more attention.

  4. Ab-initio study of surface segregation in aluminum alloys

    Energy Technology Data Exchange (ETDEWEB)

    Qin, Yifa, E-mail: yfqin10s@imr.ac.cn; Wang, Shaoqing

    2017-03-31

    Highlights: • A thorough study of surface segregation energies of 41 elements in Al is performed. • Segregation energies vary periodically with the atomic numbers of impurities. • 41 elements are classified into 3 groups according to the signs of segregation energies. • The results are validated by the surface/total concentration ratio in Al alloys. - Abstract: We have calculated surface segregation energies of 41 impurities by means of density functional theory calculations. An interesting periodical variation tendency was found for surface segregation energies derived. For the majority of main group elements, segregation energies are negative which means solute elements enrichment at Al surface is energetically more favorable than uniformly dissolution. Half of transition elements possess positive segregation energies and the energies are sensitive to surface crystallographic orientations. A strong correlation is found between the segregation energies at the Al surface and the surface energ of solute elements.

  5. Charles J. McMahon Interfacial Segregation and Embrittlement Symposium

    National Research Council Canada - National Science Library

    Vitek, Vaclav

    2003-01-01

    .... McMahon Interfacial Segregation and Embrittlement Symposium: Grain Boundary Segregation and Fracture in Steels was sponsored by ASM International, Materials Science Critical Technology Sector, Structural Materials Division, Materials Processing...

  6. Obesity detection rate among primary school students in the People's Republic of China: a meta-analysis

    Directory of Open Access Journals (Sweden)

    Jin Y

    2013-10-01

    Full Text Available Yue-long Jin,* Ling-ling Ding,* Ying-shui Yao, Xiu-li Song, Hui Tang, Lian-ping He, Yan ChenFaculty of Epidemiology and Statistics, School of Public Health, Wannan Medical College, Anhui, People's Republic of China*These authors contributed equally to this workBackground: Obesity has become a major public health problem worldwide. The prevalence of obesity is rising alarmingly among children and adolescents in the People's Republic of China, with an estimated 120 million now in the obese range. It is estimated that 8% of children in the People's Republic of China are obese and 12% are overweight.Methods: Eligible papers on the prevalence of obesity among primary school students in the People's Republic of China and published between 2006 and 2011 were retrieved from PubMed and from online Chinese periodicals, ie, the full-text databases of VIP, the Chinese National Knowledge Infrastructure, and Wan Fang. Meta-Analyst software was used to collate and analyze the detection rates cited in the papers retrieved.Results: After evaluation of the quality of the papers, 25 were finally included, giving a total sample population size for investigation of obesity of 219,763, in which 28,121 cases were detected. Meta-analysis showed that the combined obesity detection rate was 10.4% (95% confidence interval 8.6–12.6 among primary school students in the People's Republic of China, with a higher detection rate in boys (12.6% than in girls (7.2%. The prevalence of obesity was higher in the north (11.8% than in the south (9.5%, east (11.6%, and mid-west (8.0% regions. Obesity defined according to the World Health Organization weight-for-height standard (14.3% was higher than that using age-specific and gender-specific cutoff points for body mass index (9.0%.Conclusion: Our meta-analysis found an obesity prevalence rate of 10.4%, which does not seem as high as previous reports of childhood obesity rates in other countries. However, the prevalence of childhood

  7. Improving survey response rates from parents in school-based research using a multi-level approach.

    Science.gov (United States)

    Schilpzand, Elizabeth J; Sciberras, Emma; Efron, Daryl; Anderson, Vicki; Nicholson, Jan M

    2015-01-01

    While schools can provide a comprehensive sampling frame for community-based studies of children and their families, recruitment is challenging. Multi-level approaches which engage multiple school stakeholders have been recommended but few studies have documented their effects. This paper compares the impact of a standard versus enhanced engagement approach on multiple indicators of recruitment: parent response rates, response times, reminders required and sample characteristics. Parents and teachers were distributed a brief screening questionnaire as a first step for recruitment to a longitudinal study, with two cohorts recruited in consecutive years (cohort 1 2011, cohort 2 2012). For cohort 2, additional engagement strategies included the use of pre-notification postcards, improved study materials, and recruitment progress graphs provided to school staff. Chi-square and t-tests were used to examine cohort differences. Compared to cohort 1, a higher proportion of cohort 2 parents responded to the survey (76% versus 69%; p value of investing in a relatively simple multi-level strategy to maximise parent response rates, and potentially reduce recruitment time and costs.

  8. Oral-diadochokinetic rates for Hebrew-speaking school-age children: real words vs. non-words repetition.

    Science.gov (United States)

    Icht, Michal; Ben-David, Boaz M

    2015-02-01

    Oral-diadochokinesis (DDK) tasks are a common tool for evaluating speech disorders. Usually, these tasks involve repetitions of non-words. It has been suggested that repeating real words can be more suitable for preschool children. But, the impact of using real words with elementary school children has not been studied yet. This study evaluated oral-DDK rates for Hebrew-speaking elementary school children using non-words and real words. The participants were 60 children, 9-11 years old, with normal speech and language development, who were asked to repeat "pataka" (non-word) and "bodeket" (Hebrew real word). Data replicate the advantage generally found for real word repetition with preschoolers. Children produced real words faster than non-words for all age groups, and repetition rates were higher for the older children. The findings suggest that adding real words to the standard oral-DDK task with elementary school children may provide a more comprehensive picture of oro-motor function.

  9. The modelling of irradiation-enhanced phosphorus segregation in neutron irradiated reactor pressure vessel submerged-arc welds

    Energy Technology Data Exchange (ETDEWEB)

    Druce, S.G.; English, C.A.; Foreman, A.J.E.; McElroy, R.J.; Vatter, I.A. [AEA Technology, Didcot (United Kingdom). Harwell Lab.; Bolton, C.J.; Buswell, J.T.; Jones, R.B. [Nuclear Electric, Berkeley (United Kingdom). Berkeley Technology Centre

    1996-12-31

    Recent results on neutron-irradiated RPV submerged-arc welds have revealed grain boundary segregation of phosphorus during irradiation, which may lead to intergranular fracture. However, the experimental database is insufficient to define the dependence of the process on variables such ad dose, dose-rate and temperature. This paper describes work in which two existing models of phosphorus segregation, under thermal or irradiation conditions, have been developed to obtain predictions of these dependencies. The critical parameters in the models have been adjusted to give consistency with the available reference data, and predictions have been made of the dependence of segregation on a number of variables.

  10. A survey of rate of victimization and attitudes towards physical violence among school-aged children in Turkey.

    Science.gov (United States)

    Deveci, S E; Acik, Y; Ayar, A

    2008-01-01

    Violence of any type is a serious issue in the lives of many children from all racial, cultural and economic backgrounds, and is a topic of enormous societal concern in any society. The purpose of this study was to examine the rate of exposure to violence as victims, and attitudes towards physical violence among school-aged children in eastern Turkey. All the basic education schools in Elazig, a typical eastern Anatolian city, were included. A total of 3725 fifth and sixth graders were asked to answer survey questions about the rate of physical violence exposure in their everyday lives and whether they thought the violence was an 'acceptable' behaviour. The mean age of participants was 12.8 years with 46.8% boys and 53.2% girls, and their socio-economic status ranged from low-income to upper middle class. Seventy-four per cent of school-aged children reported exposure to at least one case of physical violence in their lives, and 43.4% reported experiencing physical violence within previous 12 months. Higher rates of exposure to physical violence were reported by boys than girls (P = 0.0001). Of the victims, 33.8% regarded physical violence as an acceptable or inevitable way of solution or responding to life events. Results from the self-report of the receiving end of violent behaviours indicate that physical violent victimization is at an alarmingly high rate among children of eastern Turkey, and a significant per cent of these victims approves violence as a way of solution.

  11. The Effect of Sport Specialization on Lower Extremity Injury Rates in High School Athletes

    OpenAIRE

    McGuine, Timothy A.; Bell, David; Brooks, Margaret Alison; Hetzel, Scott; Pfaller, Adam; Post, Eric

    2017-01-01

    Objectives: Sport specialization has been shown to be associated with increased risk of musculoskeletal lower extremity injuries (LEI) in adolescent athletes presenting in clinical settings. However, the association of sport specialization and incidence of LEI has not been studied prospectively in a large population of adolescent athletes. The objective of this study was to compare the incidence of LEI in high school athletes identified as having low (LOW), moderate (MOD) or high (HIGH) level...

  12. 41 CFR 60-1.8 - Segregated facilities.

    Science.gov (United States)

    2010-07-01

    ... 41 Public Contracts and Property Management 1 2010-07-01 2010-07-01 true Segregated facilities. 60...; Compliance Reports § 60-1.8 Segregated facilities. To comply with its obligations under the Order, a contractor must ensure that facilities provided for employees are provided in such a manner that segregation...

  13. Segregation effects and phase developments during solidification of alloy 625

    DEFF Research Database (Denmark)

    Højerslev, Christian; Tiedje, Niels Skat; Hald, John

    2006-01-01

    contained gamma-phase, Laves phase and, if carbon was dissolved in the liquid, niobium rich carbides formed. Molybdenum and niobium showed strong tendencies to segregate. Their segregation was balanced by inverse segregation of nickel and iron. The chromium concentration remained almost constant in gamma...

  14. Requirements for the evaluation of computational speech segregation systems

    DEFF Research Database (Denmark)

    May, Tobias; Dau, Torsten

    2014-01-01

    Recent studies on computational speech segregation reported improved speech intelligibility in noise when estimating and applying an ideal binary mask with supervised learning algorithms. However, an important requirement for such systems in technical applications is their robustness to acoustic...... associated with perceptual attributes in speech segregation. The results could help establish a framework for a systematic evaluation of future segregation systems....

  15. Residential segregation of socioeconomic variables and health indices in Iran

    Directory of Open Access Journals (Sweden)

    Seyed Saeed Hashemi Nazari

    2013-01-01

    Conclusions: Correlation of segregation of determinants of socioeconomic status with segregation of health indices is an indicator of existence of hot zones of health problems across some provinces. Further studies using multilevel modeling and individual data in health outcomes at individual level and segregation measures at appropriate geographic levels are required to confirm these relations.

  16. Factors influencing elementary school teachers' ratings of ADHD and ODD behaviors.

    Science.gov (United States)

    Stevens, J; Quittner, A L; Abikoff, H

    1998-12-01

    Examined factors that influence teachers' ratings of children with either attention deficit hyperactivity disorder (ADHD) or oppositional defiant disorder (ODD). 105 teachers watched 2 videotapes--1 depicting a normal child and the other a child with either ADHD or ODD--and rated each child using 2 different questionnaires. Results indicated that teachers accurately rated the child on the ADHD versus ODD tape as having significantly more inattention and hyperactivity but significantly less oppositionality. However, effect sizes indicated the presence of a unidirectional, negative halo effect of oppositional behaviors on ratings of hyperactivity and inattention. Teachers appeared less biased in their judgments when using a well-operationalized rating scale. Finally, knowledge, education, and experience with children with ADHD generally had no effect on the accuracy of teachers' ratings.

  17. An Examination of the Relationship between Practicing Urban School Counselors' Colorblind Racial Ideology and Social Justice Factors Such as Supports, Barriers, Self-Efficacy and Outcome Expectations, and Social Justice Interest and Commitment

    Science.gov (United States)

    Gonzalez, Ileana A.

    2012-01-01

    Groups of American students are learning at alarmingly different rates. This disparity in education is seen disproportionately in schools in urban areas, where students of color and low income students are concentrated in highly segregated areas. In urban areas, the effects of poverty, racism, and isolation are compounded by stressful environments…

  18. An Examination of Dropout Rates for Hispanic or Latino Students Enrolled in Online K-12 Schools

    Science.gov (United States)

    Corry, Michael; Dardick, William; Stella, Julie

    2017-01-01

    As the number of online K-12 educational offerings continues to grow it is important to better understand key indicators of success for students enrolled in these classes. One of those indicators is student dropout rates. This is particularly important for Hispanic or Latino students who traditionally have high dropout rates. The purpose of this…

  19. Effort-reward imbalance in the school setting: associations with somatic pain and self-rated health.

    Science.gov (United States)

    Låftman, Sara Brolin; Modin, Bitte; Östberg, Viveca; Hoven, Hanno; Plenty, Stephanie

    2015-03-01

    According to the workplace theory of effort-reward imbalance (ERI), individuals who perceive a lack of reciprocity between their effort spent at work and the rewards received in turn are at an increased risk of stress-related ill-health. It is also assumed that being overcommitted to work is linked to an increased risk of stress-related ill-health. This study applies the effort-reward imbalance model to the school setting. It aims to analyse the associations that effort-reward imbalance and overcommitment share with somatic pain and self-rated health among adolescents. Data are from the School Stress and Support Study (TriSSS), involving students in grades 8 and 9 (ages 14-16 years) in two schools in Stockholm, Sweden, during 2010 (n=403). Information on effort-reward imbalance and health outcomes was gathered from self-report questionnaires. An adjusted short version of ERI was used. Factor analysis showed that extrinsic effort, reward and overcommitment constitute three distinct dimensions. The designed measures demonstrated sound psychometric properties both for the full sample and for subgroups. Ordered logistic regressions were conducted. The analyses showed that low reward and higher overcommitment were associated with greater somatic pain and poorer self-rated health. Furthermore, effort-reward imbalance was linked with an elevated risk of somatic pain and poorer self-rated health. Students are more likely to experience stress-related ill-health when they perceive an imbalance between their effort and rewards. In addition, high overcommitment is associated with an increased risk of ill-health among students. © 2014 the Nordic Societies of Public Health.

  20. SEP PREPÁRATE: modelos de educación a distancia en el nivel medio superior SEP PREPÁRATE: e-learning models for high school

    Directory of Open Access Journals (Sweden)

    Gomez Zermeño Marcela Georgina

    2011-07-01

    Full Text Available Este documento presenta un estudio realizado sobre modelos innovadores de educación a distancia para adolescentes, con el propósito de generar información sobre los factores que permiten lograr que alumnos inscritos en programas a distancia, desarrollen las habilidades necesarias para su aprendizaje. Los alumnos que conforman la muestra de estudio, son adolescentes entre los 15 y 17 años de edad, en condiciones de rezago económico pero con necesidades propias de su edad y deseos de obtener sus estudios de preparatoria, inscritos en la Universidad TecMilenio y apoyados por la Fundación Bécalos, para que participen en el programa SEP Prepárate. Los alumnos cuentan con las herramientas necesarias para lograr sus estudios como son beca escolar, apoyo económico durante sus estudios, equipo de cómputo, conexión a Internet y Modem. Durante los trabajos de campo, se realizaron encuestas a los alumnos y padres de familia, entrevistas personales a los alumnos exitosos y a los alumnos no exitosos. El análisis de la información reveló que el programa SEP Prepárate creado por la Secretaría de Educación Pública y la Universidad Tecmilenio, es una alternativa viable que atiende las necesidades propias de los alumnos que estudian a distancia y como ayudar a los estudiantes a llegar con éxito al final de sus estudios de preparatoria. This document presents a study done about innovative e-learning models for trailed adolescents; it seeks to generate relevant information about the elements that would guarantee that enrolled students into an e-learning program develop the needed abilities for their instruction. The sample students that took part are adolescents between 15 and 17 years old, in poverty conditions but with the desire to graduate high school as any other teenager. The students are enrolled at TecMilenio University with the financial support of Fundación Bécalos, in coordination with the Mexican Ministry of Public Education, within

  1. Sister chromatid segregation in meiosis II

    Science.gov (United States)

    Wassmann, Katja

    2013-01-01

    Meiotic divisions (meiosis I and II) are specialized cell divisions to generate haploid gametes. The first meiotic division with the separation of chromosomes is named reductional division. The second division, which takes place immediately after meiosis I without intervening S-phase, is equational, with the separation of sister chromatids, similar to mitosis. This meiotic segregation pattern requires the two-step removal of the cohesin complex holding sister chromatids together: cohesin is removed from chromosome arms that have been subjected to homologous recombination in meiosis I and from the centromere region in meiosis II. Cohesin in the centromere region is protected from removal in meiosis I, but this protection has to be removed—deprotected”—for sister chromatid segregation in meiosis II. Whereas the mechanisms of cohesin protection are quite well understood, the mechanisms of deprotection have been largely unknown until recently. In this review I summarize our current knowledge on cohesin deprotection. PMID:23574717

  2. Segregation effects in welded stainless steels

    International Nuclear Information System (INIS)

    Akhter, J.I.; Shoaid, K.A.; Ahmed, M.; Malik, A.Q.

    1987-01-01

    Welding of steels causes changes in the microstructure and chemical composition which could adversely affect the mechanical and corrosion properties. The report describes the experimental results of an investigation of segregation effects in welded austenitic stainless steels of AISI type 304, 304L, 316 and 316L using the techniques of scanning electron microscopy and electron probe microanalysis. Considerable enhancement of chromium and carbon has been observed in certain well-defined zones on the parent metal and on composition, particularly in the parent metal, in attributed to the formation of (M 23 C 6 ) precipitates. The formation of geometrically well-defined segregation zones is explained on the basis of the time-temperature-precipitation curve of (M 23 C 6 ). (author)

  3. Phase Segregation in Polystyrene?Polylactide Blends

    Energy Technology Data Exchange (ETDEWEB)

    Leung, Bonnie; Hitchcock, Adam; Brash, John; Scholl, Andreas; Doran, Andrew

    2010-06-09

    Spun-cast films of polystyrene (PS) blended with polylactide (PLA) were visualized and characterized using atomic force microscopy (AFM) and synchrotron-based X-ray photoemission electron microscopy (X-PEEM). The composition of the two polymers in these systems was determined by quantitative chemical analysis of near-edge X-ray absorption signals recorded with X-PEEM. The surface morphology depends on the ratio of the two components, the total polymer concentration, and the temperature of vacuum annealing. For most of the blends examined, PS is the continuous phase with PLA existing in discrete domains or segregated to the air?polymer interface. Phase segregation was improved with further annealing. A phase inversion occurred when films of a 40:60 PS:PLA blend (0.7 wt percent loading) were annealed above the glass transition temperature (Tg) of PLA.

  4. Segregation in welded nickel-base alloys

    International Nuclear Information System (INIS)

    Akhtar, J.I.; Shoaib, K.A.; Ahmad, M.; Shaikh, M.A.

    1990-05-01

    Segregation effects have been investigated in nickel-base alloys monel 400, inconel 625, hastelloy C-276 and incoloy 825, test welded under controlled conditions. Deviations from the normal composition have been observed to varying extents in the welded zone of these alloys. Least effect of this type occurred in Monel 400 where the content of Cu increased in some of the areas. Enhancement of Al and Ti has been found over large areas in the other alloys which has been attributed to the formation of low melting slag. Another common feature is the segregation of Cr, Fe or Ti, most likely in the form of carbides. Enrichment of Al, Ti, Nb, Mb, Mo, etc., to different amounts in some of the areas of these materials is in- terpretted in terms of the formation of gamma prime precipitates or of Laves phases. (author)

  5. A Systematic Review of Consent Procedures, Participation Rates, and Main Findings of Health-Related Research in Alternative High Schools from 2010 to 2015

    Science.gov (United States)

    Johnson, Karen E.; Morris, Marian; Rew, Lynn; Simonton, Amanda J.

    2016-01-01

    There is a well-established link between educational attainment and health. Alternative high schools (AHSs) serve students who are at risk for school dropout. Health-related research conducted in AHSs has been sparse. Achieving high participation rates is critical to producing generalizable results and can be challenging in research with…

  6. High School Graduation Rates through Two Decades of District Change: The Influence of Policies, Data Records, and Demographic Shifts. Research Report

    Science.gov (United States)

    Allensworth, Elaine M.; Healey, Kaleen; Gwynne, Julia A.; Crespin, René

    2016-01-01

    High school graduation rates in the Chicago Public Schools (CPS) have shown remarkable improvements over the past 16 years. Students used to be about as likely to drop out as they were to graduate; now they are three times as likely to graduate as to drop out. Moreover, recent large improvements in the percentage of students on-track to graduate…

  7. Engineering-Based Problem Solving Strategies in AP Calculus: An Investigation into High School Student Performance on Related Rate Free-Response Problems

    Science.gov (United States)

    Thieken, John

    2012-01-01

    A sample of 127 high school Advanced Placement (AP) Calculus students from two schools was utilized to study the effects of an engineering design-based problem solving strategy on student performance with AP style Related Rate questions and changes in conceptions, beliefs, and influences. The research design followed a treatment-control multiple…

  8. The effect of primary recoil spectrum on radiation induced segregation in nickel-silicon alloys

    Science.gov (United States)

    Averback, R. S.; Rehn, L. E.; Wagner, W.; Ehrhart, P.

    1983-08-01

    Segregation of silicon to the surface of Ni-12.7 at% Si alloys during 2.0-MeV He and 3.25-MeV Kr irradiations was measured using Rutherford backscattering spectrometry. For equal calculated defect production rates the Kr irradiation was Ni-Si alloys is presented which qualitatively explains the segregation results. The model assumes that small interstitial-atom-clusters form in individual cascades and that these clusters become trapped at silicon solute atoms. The vacancy thereby becomes the more mobile defect. The model should also have relevance for the observation that void swelling in nickel is suppressed by the addition of silicon solute.

  9. Underemployment in a gender segregated labour market

    OpenAIRE

    Kjeldstad, Randi; Nymoen, Erik H.

    2010-01-01

    This article analyses factors behind underemployment in Norway and has a focus on gender. The analysis, based on Labour Force Survey data, shows that economic fluctuations during the latest one and a half decade bring about changing underemployment levels of both women and men. The Norwegian labour market is strongly gender segregated and the processes and characteristics of underemployment differ between male and female dominated labour market sectors. The former sectors are generally more e...

  10. Blood Cell Interactions and Segregation in Flow

    OpenAIRE

    Munn, Lance L.; Dupin, Michael M.

    2008-01-01

    For more than a century, pioneering researchers have been using novel experimental and computational approaches to probe the mysteries of blood flow. Thanks to their efforts, we know that blood cells generally prefer to migrate to the axis of flow, that red and white cells segregate in flow, and that cell deformability and their tendency to reversibly aggregate contribute to the non-Newtonian nature of this unique fluid. All of these properties have beneficial physiological consequences, allo...

  11. Chromosomal organization and segregation in Pseudomonas aeruginosa.

    Directory of Open Access Journals (Sweden)

    Isabelle Vallet-Gely

    2013-05-01

    Full Text Available The study of chromosomal organization and segregation in a handful of bacteria has revealed surprising variety in the mechanisms mediating such fundamental processes. In this study, we further emphasized this diversity by revealing an original organization of the Pseudomonas aeruginosa chromosome. We analyzed the localization of 20 chromosomal markers and several components of the replication machinery in this important opportunistic γ-proteobacteria pathogen. This technique allowed us to show that the 6.3 Mb unique circular chromosome of P. aeruginosa is globally oriented from the old pole of the cell to the division plane/new pole along the oriC-dif axis. The replication machinery is positioned at mid-cell, and the chromosomal loci from oriC to dif are moved sequentially to mid-cell prior to replication. The two chromosomal copies are subsequently segregated at their final subcellular destination in the two halves of the cell. We identified two regions in which markers localize at similar positions, suggesting a bias in the distribution of chromosomal regions in the cell. The first region encompasses 1.4 Mb surrounding oriC, where loci are positioned around the 0.2/0.8 relative cell length upon segregation. The second region contains at least 800 kb surrounding dif, where loci show an extensive colocalization step following replication. We also showed that disrupting the ParABS system is very detrimental in P. aeruginosa. Possible mechanisms responsible for the coordinated chromosomal segregation process and for the presence of large distinctive regions are discussed.

  12. Trends in High School Dropout and Completion Rates in the United States: 1972-2012. Compendium Report. NCES 2015-015

    Science.gov (United States)

    Stark, Patrick; Noel, Amber M.

    2015-01-01

    This report builds upon a series of National Center for Education Statistics (NCES) reports on high school dropout and completion rates that began in 1988. It presents estimates of rates in 2012, provides data about trends in dropout and completion rates over the last four decades (1972-2012), and examines the characteristics of high school…

  13. Microprobe investigation of brittle segregates in aluminum MIG and TIG welds

    Science.gov (United States)

    Larssen, P. A.; Miller, E. L.

    1968-01-01

    Quantitative microprobe analysis of segregated particles in aluminum MIG /Metal Inert Gas/ and TIG /Tungsten Inert Gas/ welds indicated that there were about ten different kinds of particles, corresponding to ten different intermetallic compounds. Differences between MIG and TIG welds related to the individual cooling rates of these welds.

  14. Infection rates of Enterobius vermicularis and Clonorchis sinensis of primary school children in Hamyang-gun, Gyeongsangnam-do (Province), Korea

    Science.gov (United States)

    Kim, Bong Jin; Yeon, Je Wook

    2001-01-01

    The egg positive rate of Enterobius vermicularis and Clonorchis sinensis of school children in the rural area was studied in Hamyang-gun. Gyeongsangnam-do in Korea. Cellotape anal swab and formalin ether concentration methods were performed one time to 720 primary school children. The total egg positive rate of E. vermicularis was 12.6% in two schools (Baekjeon and Wiseong). In the Baekjeon and Wiseong primary school, the egg positive rate of E. vermicularis was 4.6% and 13.4%, respectively. Pinworm egg positive rate was 17.6% in the lower grades (1st. 2nd and 3rd), and 7.7% in higher grades (4th, 5th and 6th). The total egg positive rate of male and female was 12.6% and 12.7%, respectively. The egg positive rate of C. sinensis of Baekjeon and Wiseong primary school was 1.5% and 0.46%, respectively. The total egg positive rate of C. sinensis was 0.56%. This survey showed that continuous education and chemotherapy is necessary to treat and prevent reinfection of E. vermicularis. In the case of C. sinensis, health education for school children is recommended to prevent potential infection of adolescents. PMID:11775334

  15. Self-organized Segregation on the Grid

    Science.gov (United States)

    Omidvar, Hamed; Franceschetti, Massimo

    2018-02-01

    We consider an agent-based model with exponentially distributed waiting times in which two types of agents interact locally over a graph, and based on this interaction and on the value of a common intolerance threshold τ , decide whether to change their types. This is equivalent to a zero-temperature ising model with Glauber dynamics, an asynchronous cellular automaton with extended Moore neighborhoods, or a Schelling model of self-organized segregation in an open system, and has applications in the analysis of social and biological networks, and spin glasses systems. Some rigorous results were recently obtained in the theoretical computer science literature, and this work provides several extensions. We enlarge the intolerance interval leading to the expected formation of large segregated regions of agents of a single type from the known size ɛ >0 to size ≈ 0.134. Namely, we show that for 0.433sites can be observed within any sufficiently large region of the occupied percolation cluster. The exponential bounds that we provide also imply that complete segregation, where agents of a single type cover the whole grid, does not occur with high probability for p=1/2 and the range of intolerance considered.

  16. Integration and segregation in auditory scene analysis

    Science.gov (United States)

    Sussman, Elyse S.

    2005-03-01

    Assessment of the neural correlates of auditory scene analysis, using an index of sound change detection that does not require the listener to attend to the sounds [a component of event-related brain potentials called the mismatch negativity (MMN)], has previously demonstrated that segregation processes can occur without attention focused on the sounds and that within-stream contextual factors influence how sound elements are integrated and represented in auditory memory. The current study investigated the relationship between the segregation and integration processes when they were called upon to function together. The pattern of MMN results showed that the integration of sound elements within a sound stream occurred after the segregation of sounds into independent streams and, further, that the individual streams were subject to contextual effects. These results are consistent with a view of auditory processing that suggests that the auditory scene is rapidly organized into distinct streams and the integration of sequential elements to perceptual units takes place on the already formed streams. This would allow for the flexibility required to identify changing within-stream sound patterns, needed to appreciate music or comprehend speech..

  17. Audiovisual segregation in cochlear implant users.

    Directory of Open Access Journals (Sweden)

    Simon Landry

    Full Text Available It has traditionally been assumed that cochlear implant users de facto perform atypically in audiovisual tasks. However, a recent study that combined an auditory task with visual distractors suggests that only those cochlear implant users that are not proficient at recognizing speech sounds might show abnormal audiovisual interactions. The present study aims at reinforcing this notion by investigating the audiovisual segregation abilities of cochlear implant users in a visual task with auditory distractors. Speechreading was assessed in two groups of cochlear implant users (proficient and non-proficient at sound recognition, as well as in normal controls. A visual speech recognition task (i.e. speechreading was administered either in silence or in combination with three types of auditory distractors: i noise ii reverse speech sound and iii non-altered speech sound. Cochlear implant users proficient at speech recognition performed like normal controls in all conditions, whereas non-proficient users showed significantly different audiovisual segregation patterns in both speech conditions. These results confirm that normal-like audiovisual segregation is possible in highly skilled cochlear implant users and, consequently, that proficient and non-proficient CI users cannot be lumped into a single group. This important feature must be taken into account in further studies of audiovisual interactions in cochlear implant users.

  18. Purely temporal figure-ground segregation.

    Science.gov (United States)

    Kandil, F I; Fahle, M

    2001-05-01

    Visual figure-ground segregation is achieved by exploiting differences in features such as luminance, colour, motion or presentation time between a figure and its surround. Here we determine the shortest delay times required for figure-ground segregation based on purely temporal features. Previous studies usually employed stimulus onset asynchronies between figure- and ground-containing possible artefacts based on apparent motion cues or on luminance differences. Our stimuli systematically avoid these artefacts by constantly showing 20 x 20 'colons' that flip by 90 degrees around their midpoints at constant time intervals. Colons constituting the background flip in-phase whereas those constituting the target flip with a phase delay. We tested the impact of frequency modulation and phase reduction on target detection. Younger subjects performed well above chance even at temporal delays as short as 13 ms, whilst older subjects required up to three times longer delays in some conditions. Figure-ground segregation can rely on purely temporal delays down to around 10 ms even in the absence of luminance and motion artefacts, indicating a temporal precision of cortical information processing almost an order of magnitude lower than the one required for some models of feature binding in the visual cortex [e.g. Singer, W. (1999), Curr. Opin. Neurobiol., 9, 189-194]. Hence, in our experiment, observers are unable to use temporal stimulus features with the precision required for these models.

  19. Minimization and segregation of radioactive wastes

    International Nuclear Information System (INIS)

    1992-07-01

    The report will serve as one of a series of technical manuals providing reference material and direct know-how to staff in radioisotope user establishments and research centres in Member States without nuclear power and the associated range of complex waste management operations. Considerations are limited to the minimization and segregation of wastes, these being initial steps on which the efficiency of the whole waste management system depends. The minimization and segregation operations are examined in the context of the restricted quantities and predominantly shorter lived activities of wastes from nuclear research, production and usage of radioisotopes. Liquid and solid wastes only are considered in the report. Gaseous waste minimization and treatment are specialized subjects and are not examined in this document. Gaseous effluent treatment in facilities handling low and intermediate level radioactive materials has been already the subject of a detailed IAEA report. Management of spent sealed sources has specifically been covered in a previous manual. Conditioned sealed sources must be taken into account in segregation arrangements for interim storage and disposal where there are exceptional long lived highly radiotoxic isotopes, particularly radium or americium. These are unlikely ever to be suitable for shallow land burial along with the remaining wastes. 30 refs, 5 figs, 8 tabs

  20. Implementing spatial segregation measures in R.

    Directory of Open Access Journals (Sweden)

    Seong-Yun Hong

    Full Text Available Reliable and accurate estimation of residential segregation between population groups is important for understanding the extent of social cohesion and integration in our society. Although there have been considerable methodological advances in the measurement of segregation over the last several decades, the recently developed measures have not been widely used in the literature, in part due to their complex calculation. To address this problem, we have implemented several newly proposed segregation indices in R, an open source software environment for statistical computing and graphics, as a package called seg. Although there are already a few standalone applications and add-on packages that provide access to similar methods, our implementation has a number of advantages over the existing tools. First, our implementation is flexible in the sense that it provides detailed control over the calculation process with a wide range of input parameters. Most of the parameters have carefully chosen defaults, which perform acceptably in many situations, so less experienced users can also use the implemented functions without too much difficulty. Second, there is no need to export results to other software programs for further analysis. We provide coercion methods that enable the transformation of our output classes into general R classes, so the user can use thousands of standard and modern statistical techniques, which are already available in R, for the post-processing of the results. Third, our implementation does not require commercial software to operate, so it is accessible to a wider group of people.

  1. Metropolitan isolation segregation and Black-White disparities in very preterm birth: a test of mediating pathways and variance explained.

    Science.gov (United States)

    Kramer, Michael R; Cooper, Hannah L; Drews-Botsch, Carolyn D; Waller, Lance A; Hogue, Carol R

    2010-12-01

    Residential isolation segregation (a measure of residential inter-racial exposure) has been associated with rates of preterm birth (births (32-36 weeks) raise questions about whether this association is similar across gestational ages, and through what pathways it might be mediated. Hierarchical Bayesian models were fit to answer three questions: is the isolation-prematurity association similar for very and moderately preterm birth; is this association mediated by maternal chronic disease, socioeconomic status, or metropolitan area crime and poverty rates; and how much of the geographic variation in Black-White very preterm birth disparities is explained by isolation segregation? Singleton births to Black and White women in 231 U.S. metropolitan statistical areas in 2000-2002 were analyzed and isolation segregation was calculated for each. We found that among Black women, isolation is associated with very preterm birth and moderately preterm birth. The association may be partially mediated by individual level socioeconomic characteristics and metropolitan level violent crime rates. There is no association between segregation and prematurity among White women. Isolation segregation explains 28% of the geographic variation in Black-White very preterm birth disparities. Our findings highlight the importance of isolation segregation for the high-burden outcome of very preterm birth, but unexplained excess risk for prematurity among Black women is substantial. Copyright © 2010 Elsevier Ltd. All rights reserved.

  2. Diabetes's 'health shock' to schooling and earnings: increased dropout rates and lower wages and employment in young adults.

    Science.gov (United States)

    Fletcher, Jason M; Richards, Michael R

    2012-01-01

    Despite a growing diabetes crisis, the nonmedical implications for young adults have gone virtually unexplored. We investigated the effects of diabetes on two key outcomes for this age group-schooling and earnings-and found that it delivers an increasingly common "health shock" to both. We identified effects in several measures of educational attainment, including a high school dropout rate that was six percentage points higher than among young adults without the disease. We also found lower employment and wages: A person with diabetes can conservatively expect to lose more than $160,000 over his or her working life, compared to a peer without the disease. For young adults with diabetes, having a parent with diabetes also leads to poorer outcomes than if one more parents do not have the disease-for example, reducing the likelihood of attending college by four to six percentage points, even after the child's health status is controlled for. These results highlight the urgency of attacking this growing health problem, as well as the need for measures such as in-school screening for whether diabetes's impact on individual learning and performance begins before the classic manifestations of clinical diabetes appear.

  3. Segregation in handling processes of blended industrial coal

    Energy Technology Data Exchange (ETDEWEB)

    Jones, M.G.; Marjanovic, P.; McGlinchy, D.; McLaren, R. [Glasgow Caledonian University, Glasgow (United Kingdom). Department of Physical Sciences, Centre for Industrial Bulk Solids Handling

    1998-09-01

    A comparison was made between two belt blending methods; using either a compartment hopper or feeder belts. The results indicated that in this case the system with feeder belts gave a more consistent proportioning of materials. Coal when formed into a heap was shown to segregate dependent on size fraction. The level of segregation for each size fraction was quantified using ANOVA statistics. Any measure taken to mitigate this segregation could then be properly assessed. Some aspects of the segregation evident in the heap arose in previous handling steps showing that such effects are transmittable along a process stream. Singles coal when pneumatically conveyed in dilute phase will segregate in the conveying pipeline. Segregation in the direction of travel was minimal in dense phase conveying although the materials tested separated through the depth of the pipe. A full scale experimental programme investigating segregation in both dense and dilute phase is currently underway. 7 refs., 2 figs., 4 tabs.

  4. Analysis of Minor Component Segregation in Ternary Powder Mixtures

    Directory of Open Access Journals (Sweden)

    Asachi Maryam

    2017-01-01

    Full Text Available In many powder handling operations, inhomogeneity in powder mixtures caused by segregation could have significant adverse impact on the quality as well as economics of the production. Segregation of a minor component of a highly active substance could have serious deleterious effects, an example is the segregation of enzyme granules in detergent powders. In this study, the effects of particle properties and bulk cohesion on the segregation tendency of minor component are analysed. The minor component is made sticky while not adversely affecting the flowability of samples. The segregation extent is evaluated using image processing of the photographic records taken from the front face of the heap after the pouring process. The optimum average sieve cut size of components for which segregation could be reduced is reported. It is also shown that the extent of segregation is significantly reduced by applying a thin layer of liquid to the surfaces of minor component, promoting an ordered mixture.

  5. Racial Residential Segregation: Measuring Location Choice Attributes of Environmental Quality and Self-Segregation

    Directory of Open Access Journals (Sweden)

    Zhaohua Zhang

    2018-04-01

    Full Text Available Both sorting on public goods and tastes for segregation contribute to the persistence of segregation in America. Incorporating Schelling’s (1969, 1971 concept of “neighborhood tipping” into a two-stage equilibrium sorting model, in which both neighborhood demographic composition and public goods (e.g., environmental quality affect households’ residential location choice, this study investigates how preferences for neighborhood demographic composition could obscure the role of exogenous public goods on segregation. The results reveal that non-white households face higher level of exposure to air pollution, suggesting the presence of environmental injustice in Franklin County, OH. Using a counterfactual scenario of switching off heterogeneous taste for environmental quality, this study identifies that sorting on Toxic Release Inventory (TRI emissions drives little correlations between emissions and demographics. However, when taste parameters of the interactions between neighborhood demographic composition and household race are eliminated, segregation (as measured by over-exposure to households of the same race of black and white households decreases by 7.63% and 16.36%, respectively, and own-race neighbor preferences contribute to segregation differently according to household income. These results may help explain some recent puzzles in the relationship between environmental quality and demographics.

  6. The Effects of the Determinants of Women's Movement Into and Out of Male-dominated Occupations on Occupational Sex Segregation.

    Science.gov (United States)

    Sheridan, Jennifer T.

    Although occupational sex segregation has decreased over the last 25 years, it is still a major social concern primarily because of the role it plays in perpetuating the gender wage gap. This paper uses data from the Wisconsin Longitudinal Study, a study that followed a random sample of 10,317 high school graduates, to assess the determinants of…

  7. Investigating stakeholders' perceptions of the link between high STD rates and the current Baltimore City Public Schools' sex education curriculum

    Science.gov (United States)

    Bolden, Shenell L. T.

    The purpose of this exploratory study was to examine key stakeholders' perceptions of the current Baltimore City Public Schools' (BCPS) sex education curriculum and to gain insight into how they believe the curriculum could be modified to be more effective. A mixed methods approach using qualitative and quantitative data collection consisting of a survey, focus group interview, and individual interviews was conducted to gather information on stakeholders' perceptions. The stakeholders included: (1) former students who received their sex education courses in the Baltimore City Public School system (BCPS); (2) teachers in BCPS who were affiliated with the sex education curriculum; (3) health care professionals who screened and/or treated East Baltimore City residents for a sexually transmitted disease (STD) and; (4) one policy maker who was responsible for creating sex education curriculum at the national level. Analysis of the quantitative data from former Baltimore City Public School students revealed a general satisfaction with the current sex education curriculum. However, qualitative data from the same group of stakeholders revealed several changes they thought should be implemented into the program in an effort to improve the current curriculum. Findings from the other groups after qualitative analysis of the interviews suggest three major themes in support of curriculum change: (1) a blended curriculum that integrates both the cognitive and affective learning domains; (2) knowledge of prevention of STD's and pregnancy; and (3) authentic teaching and learning. Results from this study strongly suggest that the Baltimore City Public School system is apathetic to the sexual health needs of students and, therefore, is inadvertently contributing to the high rate of sexually transmitted diseases among young people. Keywords: Abstinence, Affective domain, Indoctrination, Behavior Modification, Cognitive domain, Sex education curriculum, Sexually Transmitted Diseases.

  8. Heart Rate-Determined Physical Activity In New Zealand School Children: A Cross- Sectional Study

    OpenAIRE

    Michael J. Hamlin; Mick Grimley; Vicki Cowley; Chris D. Price; Jill M. Hargreaves; Jenny J. Ross

    2011-01-01

    The aim of this study was to examine current levels of physical activity determined via heart rate monitoring. A total of 176 children (85 boys, 91 girls) aged 5-13 years wore sealed Polar heart rate monitors for at least 10 hours per day on at least 3 days. Mean daily minutes of moderate to vigorous-intensity physical activity was 65 ± 43 (mean ± SD) for boys and 54 ± 37 for girls. Daily minutes of vigorous-intensity activity was 31 ± 24 and 24 ± 21 for boys and girls respectively. Significa...

  9. Improving survey response rates from parents in school-based research using a multi-level approach.

    Directory of Open Access Journals (Sweden)

    Elizabeth J Schilpzand

    Full Text Available While schools can provide a comprehensive sampling frame for community-based studies of children and their families, recruitment is challenging. Multi-level approaches which engage multiple school stakeholders have been recommended but few studies have documented their effects. This paper compares the impact of a standard versus enhanced engagement approach on multiple indicators of recruitment: parent response rates, response times, reminders required and sample characteristics.Parents and teachers were distributed a brief screening questionnaire as a first step for recruitment to a longitudinal study, with two cohorts recruited in consecutive years (cohort 1 2011, cohort 2 2012. For cohort 2, additional engagement strategies included the use of pre-notification postcards, improved study materials, and recruitment progress graphs provided to school staff. Chi-square and t-tests were used to examine cohort differences.Compared to cohort 1, a higher proportion of cohort 2 parents responded to the survey (76% versus 69%; p < 0.001, consented to participate (71% versus 56%; p < 0.001, agreed to teacher participation (90% versus 82%; p < 0.001 and agreed to follow-up contact (91% versus 80%; p < 0.001. Fewer cohort 2 parents required reminders (52% versus 63%; p < 0.001, and cohort 2 parents responded more promptly than cohort 1 parents (mean difference: 19.4 days, 95% CI: 18.0 to 20.9, p < 0.001.These results illustrate the value of investing in a relatively simple multi-level strategy to maximise parent response rates, and potentially reduce recruitment time and costs.

  10. Contesting the Public School: Reconsidering Charter Schools as Counterpublics

    Science.gov (United States)

    Wilson, Terri S.

    2016-01-01

    Although technically open to all, charter schools often emphasize distinctive missions that appeal to particular groups of students and families. These missions, especially ones focusing on ethnic, linguistic, and cultural differences, also contribute to segregation between schools. Such schools raise normative questions about the aims of…

  11. The Impact of Performance Ratings on Job Satisfaction for Public School Teachers

    Science.gov (United States)

    Koedel, Cory; Li, Jiaxi; Springer, Matthew G.; Tan, Li

    2017-01-01

    Spurred by the federal Race to the Top competition, the state of Tennessee implemented a comprehensive statewide educator evaluation system in 2011. The new system is designed to increase the rigor of evaluations and better differentiate teachers based on performance. The use of more differentiated ratings represents a significant shift in…

  12. Effect of solute segregation on thermal creep in dilute nanocyrstalline Cu alloys

    International Nuclear Information System (INIS)

    Schäfer, Jonathan; Ashkenazy, Yinon; Albe, Karsten; Averback, Robert S

    2012-01-01

    Highlights: ► Segregating solutes lower the grain boundary free volume in nanocrystalline Cu. ► Lower free volume leads to reduced atomic mobility and higher creep resistance. ► Increase in creep resistance scales with atomic size of segregating solutes. ► Atomic processes in boundaries are similar to the ones in amorphous material. - Abstract: The effect of solute segregation on thermal creep in dilute nanocrystalline alloys (Cu–Nb, Cu–Fe, Cu–Zr) was studied at elevated temperatures using molecular dynamics simulations. A combined Monte-Carlo and molecular dynamics simulation technique was first used to equilibrate the distribution of segregating solutes. Then the creep rates of the diluted Cu samples were measured as functions of temperature, composition, load and accumulated strain. In Cu–Nb samples, the creep rates were observed to increase initially with strain, but then saturate at a value close to that obtained for alloys prepared by randomly locating the solute in the grain boundaries. This behavior is attributed to an increase in grain boundary volume and energy with added chemical disorder. At high temperatures, the apparent activation energy for creep was anomalously high, 3 eV, but only 0.3 eV at lower temperatures. This temperature dependence is found to correlate with atomic mobilities in bulk Cu–Nb glasses. Calculations of creep in nanocrystalline Cu alloys containing other solutes, Fe and Zr, show that the suppression of creep rate scales with their atomic volumes when dissolved in Cu.

  13. Marijuana usage in relation to harmfulness ratings, perceived likelihood of negative consequences, and defense mechanisms in high school students.

    Science.gov (United States)

    Como-Lesko, N; Primavera, L H; Szeszko, P R

    1994-08-01

    This study investigated high school students' marijuana usage patterns in relation to their harmfulness ratings of 15 licit and illicit drugs, perceived negative consequences from using marijuana, and types of defense mechanisms employed. Subjects were classified into one of five pattern-of-use groups based on marijuana usage: principled nonusers, nonusers, light users, moderate users, and heavy users. Principled nonusers (individuals who have never used marijuana and would not do so if it was legalized) rated marijuana, hashish, cocaine, and alcohol as significantly more harmful than heavy users. A cluster analysis of the drugs' harmfulness ratings best fit a three cluster solution and were named medicinal drugs, recreational drugs, and hard drugs. In general, principled nonusers rated negative consequences from using marijuana as significantly more likely to occur than other groups. Principled nonusers and heavy users utilized reversal from the Defense Mechanism Inventory, which includes repression and denial, significantly more than nonusers, indicating some trait common to the two extreme pattern-of-use groups.

  14. Nonequilibrium segregation and phase instability in alloy films during elevated-temperature irradiation in a high-voltage electron microscope

    International Nuclear Information System (INIS)

    Lam, N.Q.; Okamoto, P.R.

    1984-05-01

    The effects of defect-production rate gradients, caused by the radial nonuniformity in the electron flux distribution, on solute segregation and phase stability in alloy films undergoing high-voltage electron-microscope (HVEM) irradiation at high temperatures are assessed. Two-dimensional (axially symmetric) compositional redistributions were calculated, taking into account both axial and transverse radial defect fluxes. It was found that when highly focused beams were employed radiation-induced segregation consisted of two stages: dominant axial segregation at the film surfaces at short irradiation times and competitive radial segregation at longer times. The average alloy composition within the irradiated region could differ greatly from that irradiated with a uniform beam, because of the additional atom transport from or to the region surrounding the irradiated zone under the influence of radial fluxes. As a result, damage-rate gradient effects must be taken into account when interpreting in-situ HVEM observations of segregation-induced phase instabilities. The theoretical predictions are compared with experimental observations of the temporal and spatial dependence of segregation-induced precipitation in thin films of Ni-Al, Ni-Ge and Ni-Si solid solutions

  15. Nonequilibrium segregation and phase instability in alloy films during elevated-temperature irradiation in a high-voltage electron microscope

    Science.gov (United States)

    Lam, N. Q.; Okamoto, P. R.

    1984-05-01

    The effects of defect-production rate gradients, caused by the radial nonuniformity in the electron flux distribution, on solute segregation and phase stability in alloy films undergoing high-voltage electron-microscope (HVEM) irradiation at high temperatures are assessed. Two-dimensional (axially symmetric) compositional redistributions were calculated, taking into account both axial and transverse radial defect fluxes. It was found that when highly focused beams were employed radiation-induced segregation consisted of two stages: dominant axial segregation at the film surfaces at short irradiation times and competitive radial segregation at longer times. The average alloy composition within the irradiated region could differ greatly from that irradiated with a uniform beam, because of the additional atom transport from or to the region surrounding the irradiated zone under the influence of radial fluxes. Damage-rate gradient effects must be taken into account when interpreting in-situ HVEM observations of segregation-induced phase instabilities. The theoretical predictions are compared with experimental observations of the temporal and spatial dependence of segregation-induced precipitation in thin films of Ni-Al, Ni-Ge and Ni-Si solid solutions.

  16. Sound segregation via embedded repetition is robust to inattention.

    Science.gov (United States)

    Masutomi, Keiko; Barascud, Nicolas; Kashino, Makio; McDermott, Josh H; Chait, Maria

    2016-03-01

    The segregation of sound sources from the mixture of sounds that enters the ear is a core capacity of human hearing, but the extent to which this process is dependent on attention remains unclear. This study investigated the effect of attention on the ability to segregate sounds via repetition. We utilized a dual task design in which stimuli to be segregated were presented along with stimuli for a "decoy" task that required continuous monitoring. The task to assess segregation presented a target sound 10 times in a row, each time concurrent with a different distractor sound. McDermott, Wrobleski, and Oxenham (2011) demonstrated that repetition causes the target sound to be segregated from the distractors. Segregation was queried by asking listeners whether a subsequent probe sound was identical to the target. A control task presented similar stimuli but probed discrimination without engaging segregation processes. We present results from 3 different decoy tasks: a visual multiple object tracking task, a rapid serial visual presentation (RSVP) digit encoding task, and a demanding auditory monitoring task. Load was manipulated by using high- and low-demand versions of each decoy task. The data provide converging evidence of a small effect of attention that is nonspecific, in that it affected the segregation and control tasks to a similar extent. In all cases, segregation performance remained high despite the presence of a concurrent, objectively demanding decoy task. The results suggest that repetition-based segregation is robust to inattention. (c) 2016 APA, all rights reserved).

  17. Climate warming causes declines in crop yields and lowers school attendance rates in Central Africa.

    Science.gov (United States)

    Fuller, Trevon L; Sesink Clee, Paul R; Njabo, Kevin Y; Tróchez, Anthony; Morgan, Katy; Meñe, Demetrio Bocuma; Anthony, Nicola M; Gonder, Mary Katherine; Allen, Walter R; Hanna, Rachid; Smith, Thomas B

    2018-01-01

    Although a number of recent studies suggest that climate associated shifts in agriculture are affecting social and economic systems, there have been relatively few studies of these effects in Africa. Such studies would be particularly useful in Central Africa, where the impacts of climate warming are predicted to be high but coincide with an area with low adaptive capacity. Focusing on plantain (Musa paradisiaca), we assess whether recent climate change has led to reduced yields. Analysis of annual temperature between 1950 and 2013 indicated a 0.8°C temperature increase over this 63-year period - a trend that is also observed in monthly temperatures in the last twenty years. From 1991 to 2011, there was a 43% decrease in plantain productivity in Central Africa, which was explained by shifts in temperature (R 2 =0.68). This decline may have reduced rural household wealth and decreased parental investment in education. Over the past two decades, there was a six month decrease in the duration of school attendance, and the decline was tightly linked to plantain yield (R 2 =0.82). By 2080, mean annual temperature is expected to increase at least 2°C in Central Africa, and our models predict a concomitant decrease of 39% in plantain yields and 51% in education outcomes, relative to the 1991 baseline. These predictions should be seen as a call-to-action for policy interventions such as farmer training programs to enhance the adaptive capacity of food production systems to mitigate impacts on rural income and education. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. School Integration Matters: Research-Based Strategies to Advance Equity

    Science.gov (United States)

    Frankenberg, Erica, Ed.; Garces, Liliana M., Ed.; Hopkins, Megan, Ed.

    2016-01-01

    More than 60 years after the "Brown v. Board of Education" decision declared segregated schooling inherently unequal, this timely book sheds light on how and why U.S. schools are experiencing increasing segregation along racial, socioeconomic, and linguistic lines. It offers policy and programmatic alternatives for advancing equity and…

  19. Correlation between brain circuit segregation and obesity.

    Science.gov (United States)

    Chao, Seh-Huang; Liao, Yin-To; Chen, Vincent Chin-Hung; Li, Cheng-Jui; McIntyre, Roger S; Lee, Yena; Weng, Jun-Cheng

    2018-01-30

    Obesity is a major public health problem. Herein, we aim to identify the correlation between brain circuit segregation and obesity using multimodal functional magnetic resonance imaging (fMRI) techniques and analysis. Twenty obese patients (BMI=37.66±5.07) and 30 healthy controls (BMI=22.64±3.45) were compared using neuroimaging and assessed for symptoms of anxiety and depression using the Hospital Anxiety and Depression Scale (HADS). All participants underwent resting-state fMRI (rs-fMRI) and T1-weighted imaging using a 1.5T MRI. Multimodal MRI techniques and analyses were used to assess obese patients, including the functional connectivity (FC), amplitude of low-frequency fluctuations (ALFF), regional homogeneity (ReHo), graph theoretical analysis (GTA), and voxel-based morphometry (VBM). Correlations between brain circuit segregation and obesity were also calculated. In the VBM, obese patients showed altered gray matter volumes in the amygdala, thalamus and putamen. In the FC, the obesity group showed increased functional connectivity in the bilateral anterior cingulate cortex and decreased functional connectivity in the frontal gyrus of default mode network. The obesity group also exhibited altered ALFF and ReHo in the prefrontal cortex and precuneus. In the GTA, the obese patients showed a significant decrease in local segregation and a significant increase in global integration, suggesting a shift toward randomization in their functional networks. Our results may provide additional evidence for potential structural and functional imaging markers for clinical diagnosis and future research, and they may improve our understanding of the underlying pathophysiology of obesity. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Components of segregation distortion in Drosophila melanogaster

    International Nuclear Information System (INIS)

    Ganetzky, B.

    1977-01-01

    The segregation distorter (SD) complex is a naturally occurring meiotic drive system with the property that males heterozygous for an SD-bearing chromosome 2 and an SD+-bearing homolog transmit the SD-bearing chromosome almost exclusively. This distorted segregation is the consequence of an induced dysfunction of those sperm that receive the SD+ homolog. From previous studies, two loci have been implicated in this phenomenon: the Sd locus which is required to produce distortion, and the Responder (Rsp) locus that is the site at which Sd acts. There are two allelic alternatives of Rsp-sensitive (Rsp/sup sens/) and insensitive (Rsp/sup ins/); a chromosome carrying Rsp/sup ins/ is not distorted by SD. In the present study, the function and location of each of these elements was examined by a genetic and cytological characterization of x-ray-induced mutations at each locus. The results indicate the following: the Rsp locus is located in the proximal heterochromatin of 2R; a deletion for the Rsp locus renders a chromosome insensitive to distortion; the Sd locus is located to the left of pr (2-54.5), in the region from 37D2-D7 to 38A6-B2 of the salivary chromosome map; an SD chromosome deleted for Sd loses its ability to distort; there is another important component of the SD system, E(SD), in or near the proximal heterochromatin of 2L, that behaves as a strong enhancer of distortion. The results of these studies allow a reinterpretation of results from earlier analyses of the SD system and serve to limit the possible mechanisms to account for segregation distortion

  1. Segregation and integration of auditory streams when listening to multi-part music.

    Science.gov (United States)

    Ragert, Marie; Fairhurst, Merle T; Keller, Peter E

    2014-01-01

    In our daily lives, auditory stream segregation allows us to differentiate concurrent sound sources and to make sense of the scene we are experiencing. However, a combination of segregation and the concurrent integration of auditory streams is necessary in order to analyze the relationship between streams and thus perceive a coherent auditory scene. The present functional magnetic resonance imaging study investigates the relative role and neural underpinnings of these listening strategies in multi-part musical stimuli. We compare a real human performance of a piano duet and a synthetic stimulus of the same duet in a prioritized integrative attention paradigm that required the simultaneous segregation and integration of auditory streams. In so doing, we manipulate the degree to which the attended part of the duet led either structurally (attend melody vs. attend accompaniment) or temporally (asynchronies vs. no asynchronies between parts), and thus the relative contributions of integration and segregation used to make an assessment of the leader-follower relationship. We show that perceptually the relationship between parts is biased towards the conventional structural hierarchy in western music in which the melody generally dominates (leads) the accompaniment. Moreover, the assessment varies as a function of both cognitive load, as shown through difficulty ratings and the interaction of the temporal and the structural relationship factors. Neurally, we see that the temporal relationship between parts, as one important cue for stream segregation, revealed distinct neural activity in the planum temporale. By contrast, integration used when listening to both the temporally separated performance stimulus and the temporally fused synthetic stimulus resulted in activation of the intraparietal sulcus. These results support the hypothesis that the planum temporale and IPS are key structures underlying the mechanisms of segregation and integration of auditory streams

  2. Segregation and integration of auditory streams when listening to multi-part music.

    Directory of Open Access Journals (Sweden)

    Marie Ragert

    Full Text Available In our daily lives, auditory stream segregation allows us to differentiate concurrent sound sources and to make sense of the scene we are experiencing. However, a combination of segregation and the concurrent integration of auditory streams is necessary in order to analyze the relationship between streams and thus perceive a coherent auditory scene. The present functional magnetic resonance imaging study investigates the relative role and neural underpinnings of these listening strategies in multi-part musical stimuli. We compare a real human performance of a piano duet and a synthetic stimulus of the same duet in a prioritized integrative attention paradigm that required the simultaneous segregation and integration of auditory streams. In so doing, we manipulate the degree to which the attended part of the duet led either structurally (attend melody vs. attend accompaniment or temporally (asynchronies vs. no asynchronies between parts, and thus the relative contributions of integration and segregation used to make an assessment of the leader-follower relationship. We show that perceptually the relationship between parts is biased towards the conventional structural hierarchy in western music in which the melody generally dominates (leads the accompaniment. Moreover, the assessment varies as a function of both cognitive load, as shown through difficulty ratings and the interaction of the temporal and the structural relationship factors. Neurally, we see that the temporal relationship between parts, as one important cue for stream segregation, revealed distinct neural activity in the planum temporale. By contrast, integration used when listening to both the temporally separated performance stimulus and the temporally fused synthetic stimulus resulted in activation of the intraparietal sulcus. These results support the hypothesis that the planum temporale and IPS are key structures underlying the mechanisms of segregation and integration of

  3. Dynamics of chromosome segregation in Escherichia coli

    DEFF Research Database (Denmark)

    Nielsen, Henrik Jørck

    2007-01-01

    Since the 1960’es the conformation and segregation of the chromosome in Escherichia coli has been a subject of interest for many scientists. However, after 40 years of research, we still know incredibly little about how the chromosome is organized inside the cell, how it manages to duplicate...... this incredibly big molecule and separate the two daughter chromosomes and how it makes sure that the daughter cells receives one copy each. The fully extended chromosome is two orders of magnitude larger than the cell in which it is contained. Hence the chromosome is heavily compacted in the cell...

  4. Grain size segregation in debris discs

    Science.gov (United States)

    Thebault, P.; Kral, Q.; Augereau, J.-C.

    2014-01-01

    Context. In most debris discs, dust grain dynamics is strongly affected by stellar radiation pressure. Because this mechanism is size-dependent, we expect dust grains to be spatially segregated according to their sizes. However, because of the complex interplay between radiation pressure, grain processing by collisions, and dynamical perturbations, this spatial segregation of the particle size distribution (PSD) has proven difficult to investigate and quantify with numerical models. Aims: We propose to thoroughly investigate this problem by using a new-generation code that can handle some of the complex coupling between dynamical and collisional effects. We intend to explore how PSDs behave in both unperturbed discs at rest and in discs pertubed by planetary objects. Methods: We used the DyCoSS code to investigate the coupled effect of collisions, radiation pressure, and dynamical perturbations in systems that have reached a steady-state. We considered two setups: a narrow ring perturbed by an exterior planet, and an extended disc into which a planet is embedded. For both setups we considered an additional unperturbed case without a planet. We also investigated the effect of possible spatial size segregation on disc images at different wavelengths. Results: We find that PSDs are always spatially segregated. The only case for which the PSD follows a standard dn ∝ s-3.5ds law is for an unperturbed narrow ring, but only within the parent-body ring itself. For all other configurations, the size distributions can strongly depart from such power laws and have steep spatial gradients. As an example, the geometrical cross-section of the disc is very rarely dominated by the smallest grains on bound orbits, as it is expected to be in standard PSDs in sq with q ≤ -3. Although the exact profiles and spatial variations of PSDs are a complex function of the set-up that is considered, we are still able to derive some reliable results that will be useful for image or SED

  5. Cost segregation of assets offers tax benefits.

    Science.gov (United States)

    Grant, D A

    2001-04-01

    A cost-segregation study is an asset-reclassification strategy that accelerates tax-depreciation deductions. By using this strategy, healthcare facility owners can lower their current income-tax liability and increase current cash flow. Simply put, certain real estate is reclassified from long-lived real property to shorter-lived personal property for depreciation purposes. Depreciation deductions for the personal property then can be greatly accelerated, thereby producing greater present-value tax savings. An analysis of costs can be conducted from either detailed construction records, when such records are available, or by using qualified appraisers, architects, or engineers to perform the allocation analysis.

  6. The Production of Professional School Counselors in Alabama: Graduation Rates of CACREP and Non-CACREP Programs

    Science.gov (United States)

    Boes, Susan R.; Snow, Brent M.; Chibbaro, Julie S.

    2009-01-01

    Today's professional school counselors have many roles and tasks within the schools. As more children depend on the services of school counselors, well-trained counselors are needed to meet the demands. Data presented in this paper provide support for the production of professional school counselors in Alabama and the immediate southeastern area…

  7. Radiation induced phosphorus segregation in austenitic and ferritic alloys

    International Nuclear Information System (INIS)

    Brimhall, J.L.; Baer, D.R.; Jones, R.H.

    1984-01-01

    The radiation induced surface segregation (RIS) of phosphorus in stainless steel attained a maximum at a dose of 0.8 dpa then decreased continually with dose. This decrease in the surface segregation of phosphorus at high dose levels has been attributed to removal of the phosphorus layer by ion sputtering. Phosphorus is not replenished since essentially all of the phosphorus within the irradiation zone has been segregated to the surface. Sputter removal can explain the previously reported absence of phosphorus segregation in ferritic alloys irradiated at high dosessup(1,2) (>1 dpa) since irradiation of ferritic alloys to low doses has shown measurable RIS. This sputtering phenomenon places an inherent limitation to the heavy ion irradiation technique for the study of surface segregation of impurity elements. The magnitude of the segregation in ferritics is still much less than in stainless steel which can be related to the low damage accumulation in these alloys. (orig.)

  8. Surface segregation in binary alloy first wall candidate materials

    International Nuclear Information System (INIS)

    Gruen, D.M.; Krauss, A.R.; Mendelsohn, M.H.; Susman, S.; Argonne National Lab., IL

    1982-01-01

    We have been studying the conditions necessary to produce a self-sustaining stable lithium monolayer on a metal substrate as a means of creating a low-Z film which sputters primarily as secondary ions. It is expected that because of the toroidal field, secondary ions originating at the first wall will be returned and contribute little to the plasma impurity influx. Aluminum and copper have, because of their high thermal conductivity and low induced radioactivity, been proposed as first wall candidate materials. The mechanical properties of the pure metals are very poorly suited to structural applications and an alloy must be used to obtain adequate hardness and tensile strength. In the case of aluminum, mechanical properties suitable for aircraft manufacture are obtained by the addition of a few at% Li. In order to investigate alloys of a similar nature as candidate structural materials for fusion machines we have prepared samples of Li-doped aluminum using both a pyro-metallurgical and a vapor-diffusion technique. The sputtering properties and surface composition have been studied as a function of sample temperature and heating time, and ion beam mass. The erosion rate and secondary ion yield of both the sputtered Al and Li have been monitored by secondary ion mass spectroscopy and Auger analysis providing information on surface segregation, depth composition profiles, and diffusion rates. The surface composition ahd lithium depth profiles are compared with previously obtained computational results based on a regular solution model of segregation, while the partial sputtering yields of Al and Li are compared with results obtained with a modified version of the TRIM computer program. (orig.)

  9. Students' motivational processes and their relationship to teacher ratings in school physical education: a self-determination theory approach.

    Science.gov (United States)

    Standage, Martyn; Duda, Joan L; Ntoumanis, Nikos

    2006-03-01

    In the present study, we used a model of motivation grounded in self-determination theory (Deci & Ryan, 1985, 1991; Ryan & Deci, 2000a, 2000b, 2002) to examine the relationship between physical education (PE) students' motivational processes and ratings of their effort and persistence as provided by their PE teacher. Data were obtained from 394 British secondary school students (204 boys, 189 girls, 1 gender not specified; M age = 11.97 years; SD = .89; range = 11-14 years) who responded to a multisection inventory (tapping autonomy-support, autonomy, competence, relatedness, and self-determined motivation). The students' respective PE teachers subsequently provided ratings reflecting the effort and persistence each student exhibited in their PE classes. The hypothesized relationships among the study variables were examined via structural equation modeling analysis using latent factors. Results of maximum likelihood analysis using the bootstrapping method revealed the proposed model demonstrated a good fit to the data, chi-squared (292) = 632.68, p self-determination. Student-reported levels of self-determined motivation positively predicted teacher ratings of effort and persistence in PE. The findings are discussed with regard to enhancing student motivation in PE settings.

  10. Cardiorespiratory endurance evaluation using heart rate analysis during ski simulator exercise and the Harvard step test in elementary school students.

    Science.gov (United States)

    Lee, Hyo Taek; Roh, Hyo Lyun; Kim, Yoon Sang

    2016-01-01

    [Purpose] Efficient management using exercise programs with various benefits should be provided by educational institutions for children in their growth phase. We analyzed the heart rates of children during ski simulator exercise and the Harvard step test to evaluate the cardiopulmonary endurance by calculating their post-exercise recovery rate. [Subjects and Methods] The subjects (n = 77) were categorized into a normal weight and an overweight/obesity group by body mass index. They performed each exercise for 3 minutes. The cardiorespiratory endurance was calculated using the Physical Efficiency Index formula. [Results] The ski simulator and Harvard step test showed that there was a significant difference in the heart rates of the 2 body mass index-based groups at each minute. The normal weight and the ski-simulator group had higher Physical Efficiency Index levels. [Conclusion] This study showed that a simulator exercise can produce a cumulative load even when performed at low intensity, and can be effectively utilized as exercise equipment since it resulted in higher Physical Efficiency Index levels than the Harvard step test. If schools can increase sport durability by stimulating students' interests, the ski simulator exercise can be used in programs designed to improve and strengthen students' physical fitness.

  11. Examining parents' ratings of middle-school students' academic self-regulation using principal axis factoring analysis.

    Science.gov (United States)

    Chen, Peggy P; Cleary, Timothy J; Lui, Angela M

    2015-09-01

    This study examined the reliability and validity of a parent rating scale, the Self-Regulation Strategy Inventory: Parent Rating Scale (SRSI-PRS), using a sample of 451 parents of sixth- and seventh-grade middle-school students. Principal axis factoring (PAF) analysis revealed a 3-factor structure for the 23-item SRSI-PRS: (a) Managing Behavior and Learning (α = .92), (b) Maladaptive Regulatory Behaviors (α = .76), and (c) Managing Environment (α = .84). The majority of the observed relations between these 3 subscales, and the SRSI-SR, student motivation beliefs, and student mathematics grades were statistically significant and in the small to medium range. After controlling for various student variables and motivation indices of parental involvement, 2 SRSI-PRS factors (Managing Behavior and Learning, Maladaptive Regulatory Behaviors) reliably predicted students' achievement in their mathematics course. This study provides initial support for the validity and reliability of the SRSI-PRS and underscores the advantages of obtaining parental ratings of students' SRL behaviors. (c) 2015 APA, all rights reserved).

  12. Examining Parents' Ratings of Middle-School Students' Academic Self-Regulation Using Principal Axis Factoring Analysis

    Science.gov (United States)

    Chen, Peggy P.; Cleary, Timothy J.; Lui, Angela M.

    2015-01-01

    This study examined the reliability and validity of a parent rating scale, the "Self-Regulation Strategy Inventory: Parent Rating Scale" ("SRSI-PRS"), using a sample of 451 parents of sixth- and seventh-grade middle-school students. Principal axis factoring (PAF) analysis revealed a 3-factor structure for the 23-item SRSI-PRS:…

  13. Growth Conditions Regulate the Requirements for Caulobacter Chromosome Segregation

    DEFF Research Database (Denmark)

    Shebelut, Conrad W.; Jensen, Rasmus Bugge; Gitai, Zemer

    2009-01-01

    Growth environments are important metabolic and developmental regulators. Here we demonstrate a growth environment-dependent effect on Caulobacter chromosome segregation of a small-molecule inhibitor of the MreB bacterial actin cytoskeleton. Our results also implicate ParAB as important segregation...... determinants, suggesting that multiple distinct mechanisms can mediate Caulobacter chromosome segregation and that their relative contributions can be environmentally regulated....

  14. Segregation-mobility feedback for bidisperse shallow granular flows: Towards understanding segregation in geophysical flows

    Science.gov (United States)

    Thornton, A.; Denissen, I.; Weinhart, T.; Van der Vaart, K.

    2017-12-01

    The flow behaviour of shallow granular chute flows for uniform particles is well-described by the hstop-rheology [1]. Geophysical flows, however, are often composed of highly non-uniform particles that differ in particle (size, shape, composition) or contact (friction, dissipation, cohesion) properties. The flow behaviour of such mixtures can be strongly influenced by particle segregation effects. Here, we study the influence of particle size-segregation on the flow behaviour of bidisperse flows using experiments and the discrete particle method. We use periodic DPM to derive hstop-rheology for the bi-dispersed granular shallow layer equations, and study their dependence on the segregation profile. In the periodic box simulations, size-segregation results in an upward coarsening of the size distribution with the largest grains collecting at the top of the flow. In geophysical flows, the fact the flow velocity is greatest at the top couples with the vertical segregation to preferentially transported large particles to the front. The large grains may be overrun, resegregated towards the surface and recirculated before being shouldered aside into lateral levees. Theoretically it has been suggested this process should lead to a breaking size-segregation (BSS) wave located between a large-particle-rich front and a small-particle-rich tail [2,3]. In the BSS wave large particles that have been overrun rise up again to the free-surface while small particles sink to the bed. We present evidence for the existences of the BSS wave. This is achieved through the study of three-dimensional bidisperse granular flows in a moving-bed channel. Our analysis demonstrates a relation between the concentration of small particles in the flow and the amount of basal slip, in which the structure of the BSS wave plays a key role. This leads to a feedback between the mean bulk flow velocity and the process of size-segregation. Ultimately, these findings shed new light on the recirculation of

  15. Decentralization as a Cause of Spatial Segregation

    Directory of Open Access Journals (Sweden)

    Jasarovic Ema Alihodzic

    2016-01-01

    Full Text Available City represents an incomplete dynamic process prone to the expansion with a causal link between urban expansion and socio-spatial segregation. The socio-spatial distribution in the city is mostly related to the increased social polarization and inequality. There is a clear connection between divided society and divided city: if society is divided, urban space must be divided. It is the question of the relations between the social inequalities on one hand, and spatial segregation on the other. In the last 10 years, Podgorica is the city that shows alarming statistic values when it comes to demographic trends and the influx of the residents from the northern municipalities, which necessarily causes the city sprawl. Past experiences show that city is unevenly expanding, creating new functions and zones expressed by socio-spatial differences. The beginning of this process lies in modernist conception of the city, by which city was mostly developed, while the current functional organization is based on the same concept. With the first urban plans, which carried similarproblems mentioned in previous section, Podgorica was divided into three clearly differentiated zones: Stara Varoš, Nova Varoš and Novi grad, which became a platform for hierarchical divisions within the space, reflecting them in the society.

  16. Binaural segregation in multisource reverberant environments.

    Science.gov (United States)

    Roman, Nicoleta; Srinivasan, Soundararajan; Wang, DeLiang

    2006-12-01

    In a natural environment, speech signals are degraded by both reverberation and concurrent noise sources. While human listening is robust under these conditions using only two ears, current two-microphone algorithms perform poorly. The psychological process of figure-ground segregation suggests that the target signal is perceived as a foreground while the remaining stimuli are perceived as a background. Accordingly, the goal is to estimate an ideal time-frequency (T-F) binary mask, which selects the target if it is stronger than the interference in a local T-F unit. In this paper, a binaural segregation system that extracts the reverberant target signal from multisource reverberant mixtures by utilizing only the location information of target source is proposed. The proposed system combines target cancellation through adaptive filtering and a binary decision rule to estimate the ideal T-F binary mask. The main observation in this work is that the target attenuation in a T-F unit resulting from adaptive filtering is correlated with the relative strength of target to mixture. A comprehensive evaluation shows that the proposed system results in large SNR gains. In addition, comparisons using SNR as well as automatic speech recognition measures show that this system outperforms standard two-microphone beamforming approaches and a recent binaural processor.

  17. Sound source localization and segregation with internally coupled ears

    DEFF Research Database (Denmark)

    Bee, Mark A; Christensen-Dalsgaard, Jakob

    2016-01-01

    to their correct sources (sound source segregation). Here, we review anatomical, biophysical, neurophysiological, and behavioral studies aimed at identifying how the internally coupled ears of frogs contribute to sound source localization and segregation. Our review focuses on treefrogs in the genus Hyla......, as they are the most thoroughly studied frogs in terms of sound source localization and segregation. They also represent promising model systems for future work aimed at understanding better how internally coupled ears contribute to sound source localization and segregation. We conclude our review by enumerating...

  18. Dysfunctional MreB inhibits chromosome segregation in Escherichia coli

    DEFF Research Database (Denmark)

    Kruse, Thomas; Møller-Jensen, Jakob; Løbner-Olesen, Anders

    2003-01-01

    The mechanism of prokaryotic chromosome segregation is not known. MreB, an actin homolog, is a shape-determining factor in rod-shaped prokaryotic cells. Using immunofluorescence microscopy we found that MreB of Escherichia coli formed helical filaments located beneath the cell surface. Flow...... cytometric and cytological analyses indicated that MreB-depleted cells segregated their chromosomes in pairs, consistent with chromosome cohesion. Overexpression of wild-type MreB inhibited cell division but did not perturb chromosome segregation. Overexpression of mutant forms of MreB inhibited cell...... that MreB filaments participate in directional chromosome movement and segregation....

  19. Preferences, constraints, and the process of sex segregation in college majors: A choice analysis.

    Science.gov (United States)

    Ochsenfeld, Fabian

    2016-03-01

    The persistence of horizontal sex segregation in higher education continues to puzzle social scientists. To help resolve this puzzle, we analyze a sample of college entrants in Germany with a discrete choice design that allows for social learning from the experiences of others. We make at least two contributions to the state of research. First, we test whether essentialist gender stereotypes affect major selection mostly through internalization or rather as external constraints that high school graduates adapt their behavior to. Empirically, we find that internalized vocational interests better explain gendered major choices than conformance with friends' and parents' expectations does. Second, we scrutinize whether segregation results from women's anticipation of gendered family roles or from their anticipation of sex-based discrimination, but we find no evidence for either of these hypotheses. As in most previous studies, differences in mathematics achievement fail to explain gendered patterns of selection into college majors. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Sound stream segregation: a neuromorphic approach to solve the “cocktail party problem” in real-time

    Science.gov (United States)

    Thakur, Chetan Singh; Wang, Runchun M.; Afshar, Saeed; Hamilton, Tara J.; Tapson, Jonathan C.; Shamma, Shihab A.; van Schaik, André

    2015-01-01

    The human auditory system has the ability to segregate complex auditory scenes into a foreground component and a background, allowing us to listen to specific speech sounds from a mixture of sounds. Selective attention plays a crucial role in this process, colloquially known as the “cocktail party effect.” It has not been possible to build a machine that can emulate this human ability in real-time. Here, we have developed a framework for the implementation of a neuromorphic sound segregation algorithm in a Field Programmable Gate Array (FPGA). This algorithm is based on the principles of temporal coherence and uses an attention signal to separate a target sound stream from background noise. Temporal coherence implies that auditory features belonging to the same sound source are coherently modulated and evoke highly correlated neural response patterns. The basis for this form of sound segregation is that responses from pairs of channels that are strongly positively correlated belong to the same stream, while channels that are uncorrelated or anti-correlated belong to different streams. In our framework, we have used a neuromorphic cochlea as a frontend sound analyser to extract spatial information of the sound input, which then passes through band pass filters that extract the sound envelope at various modulation rates. Further stages include feature extraction and mask generation, which is finally used to reconstruct the targeted sound. Using sample tonal and speech mixtures, we show that our FPGA architecture is able to segregate sound sources in real-time. The accuracy of segregation is indicated by the high signal-to-noise ratio (SNR) of the segregated stream (90, 77, and 55 dB for simple tone, complex tone, and speech, respectively) as compared to the SNR of the mixture waveform (0 dB). This system may be easily extended for the segregation of complex speech signals, and may thus find various applications in electronic devices such as for sound segregation

  1. Sound stream segregation: a neuromorphic approach to solve the ‘cocktail party problem’ in real-time

    Directory of Open Access Journals (Sweden)

    Chetan Singh Thakur

    2015-09-01

    Full Text Available The human auditory system has the ability to segregate complex auditory scenes into a foreground component and a background, allowing us to listen to specific speech sounds from a mixture of sounds. Selective attention plays a crucial role in this process, colloquially known as the ‘cocktail party effect’. It has not been possible to build a machine that can emulate this human ability in real-time. Here, we have developed a framework for the implementation of a neuromorphic sound segregation algorithm in a Field Programmable Gate Array (FPGA. This algorithm is based on the principles of temporal coherence and uses an attention signal to separate a target sound stream from background noise. Temporal coherence implies that auditory features belonging to the same sound source are coherently modulated and evoke highly correlated neural response patterns. The basis for this form of sound segregation is that responses from pairs of channels that are strongly positively correlated belong to the same stream, while channels that are uncorrelated or anti-correlated belong to different streams. In our framework, we have used a neuromorphic cochlea as a frontend sound analyser to extract spatial information of the sound input, which then passes through band pass filters that extract the sound envelope at various modulation rates. Further stages include feature extraction and mask generation, which is finally used to reconstruct the targeted sound. Using sample tonal and speech mixtures, we show that our FPGA architecture is able to segregate sound sources in real-time. The accuracy of segregation is indicated by the high signal-to-noise ratio (SNR of the segregated stream (90, 77 and 55 dB for simple tone, complex tone and speech, respectively as compared to the SNR of the mixture waveform (0 dB. This system may be easily extended for the segregation of complex speech signals, and may thus find various applications in electronic devices such as for

  2. A Large Scale Study of the Assessment of the Social Environment of Middle and Secondary Schools: The Validity and Utility of Teachers' Ratings of School Climate, Cultural Pluralism, and Safety Problems for Understanding School Effects and School Improvement

    Science.gov (United States)

    Brand, Stephen; Felner, Robert D.; Seitsinger, Anne; Burns, Amy; Bolton, Natalie

    2008-01-01

    Due to changes in state and federal policies, as well as logistical and fiscal limitations, researchers must increasingly rely on teachers' reports of school climate dimensions in order to investigate the developmental impact of these dimensions, and to evaluate efforts to enhance the impact of school environments on the development of young…

  3. Impact of influenza vaccination on respiratory illness rates in children attending private boarding schools in England, 2013-2014: a cohort study.

    Science.gov (United States)

    Brousseau, N; Green, H K; Andrews, N; Pryse, R; Baguelin, M; Sunderland, A; Ellis, J; Pebody, R

    2015-12-01

    Several private boarding schools in England have established universal influenza vaccination programmes for their pupils. We evaluated the impact of these programmes on the burden of respiratory illnesses in boarders. Between November 2013 and May 2014, age-specific respiratory disease incidence rates in boarders were compared between schools offering and not offering influenza vaccine to healthy boarders. We adjusted for age, sex, school size and week using negative binomial regression. Forty-three schools comprising 14 776 boarders participated. Almost all boarders (99%) were aged 11-17 years. Nineteen (44%) schools vaccinated healthy boarders against influenza, with a mean uptake of 48·5% (range 14·2-88·5%). Over the study period, 1468 respiratory illnesses were reported in boarders (5·66/1000 boarder-weeks); of these, 33 were influenza-like illnesses (ILIs, 0·26/1000 boarder-weeks) in vaccinating schools and 95 were ILIs (0·74/1000 boarder-weeks) in non-vaccinating schools. The impact of vaccinating healthy boarders was a 54% reduction in ILI in all boarders [rate ratio (RR) 0·46, 95% confidence interval (CI) 0·28-0·76]. Disease rates were also reduced for upper respiratory tract infections (RR 0·72, 95% CI 0·61-0·85) and chest infections (RR 0·18, 95% CI 0·09-0·36). These findings demonstrate a significant impact of influenza vaccination on ILI and other clinical endpoints in secondary-school boarders. Additional research is needed to investigate the impact of influenza vaccination in non-boarding secondary-school settings.

  4. Dropout rates in medical students at one school before and after the installation of admission tests in Austria.

    Science.gov (United States)

    Reibnegger, Gilbert; Caluba, Hans-Christian; Ithaler, Daniel; Manhal, Simone; Neges, Heide Maria; Smolle, Josef

    2011-08-01

    Admission to medical studies in Austria since academic year 2005-2006 has been regulated by admission tests. At the Medical University of Graz, an admission test focusing on secondary-school-level knowledge in natural sciences has been used for this purpose. The impact of this important change on dropout rates of female versus male students and older versus younger students is reported. All 2,860 students admitted to the human medicine diploma program at the Medical University of Graz from academic years 2002-2003 to 2008-2009 were included. Nonparametric and semiparametric survival analysis techniques were employed to compare cumulative probability of dropout between demographic groups. Cumulative probability of dropout was significantly reduced in students selected by active admission procedure versus those admitted openly (P students was only 0.145 (95% CI, 0.106-0.198). Among openly admitted students, but not for selected ones, the cumulative probabilities for dropout were higher for females (P students (P dropout hazard is highest during the second year of study. The introduction of admission testing significantly decreased the cumulative probability for dropout. In openly admitted students a significantly higher risk for dropout was found in female students and in older students, whereas no such effects can be detected after admission testing. Future research should focus on the sex dependence, with the aim of improving success rates among female applicants on the admission tests.

  5. Repair rather than segregation of damage is the optimal unicellular aging strategy.

    Science.gov (United States)

    Clegg, Robert J; Dyson, Rosemary J; Kreft, Jan-Ulrich

    2014-08-16

    How aging, being unfavourable for the individual, can evolve is one of the fundamental problems of biology. Evidence for aging in unicellular organisms is far from conclusive. Some studies found aging even in symmetrically dividing unicellular species; others did not find aging in the same, or in different, unicellular species, or only under stress. Mathematical models suggested that segregation of non-genetic damage, as an aging strategy, would increase fitness. However, these models failed to consider repair as an alternative strategy or did not properly account for the benefits of repair. We used a new and improved individual-based model to examine rigorously the effect of a range of aging strategies on fitness in various environments. Repair of damage emerges as the best strategy despite its fitness costs, since it immediately increases growth rate. There is an optimal investment in repair that outperforms damage segregation in well-mixed, lasting and benign environments over a wide range of parameter values. Damage segregation becomes beneficial, and only in combination with repair, when three factors are combined: (i) the rate of damage accumulation is high, (ii) damage is toxic and (iii) efficiency of repair is low. In contrast to previous models, our model predicts that unicellular organisms should have active mechanisms to repair damage rather than age by segregating damage. Indeed, as predicted, all organisms have evolved active mechanisms of repair whilst aging in unicellular organisms is absent or minimal under benign conditions, apart from microorganisms with a different ecology, inhabiting short-lived environments strongly favouring early reproduction rather than longevity. Aging confers no fitness advantage for unicellular organisms in lasting environments under benign conditions, since repair of non-genetic damage is better than damage segregation.

  6. Searching for Silver Linings: Is Perceived Medical Discrimination Weaker in Segregated Areas?

    Science.gov (United States)

    Gibbons, Joseph; Yang, Tse-Chuan

    2018-03-01

    An ongoing obstacle in dealing with minority health disparities is discriminatory behavior from healthcare practitioners, also known as medical discrimination. It is not clear, however, if the effects of medical discriminations onto health are constant across space. For example, there is evidence to suspect minorities in racially segregated neighborhoods suffer less from discrimination compared to those living elsewhere. To determine the presence of spatial heterogeneity underlying medical discrimination, we implement logistic geographically weighted regression (GWR) using individual data in the city of Philadelphia from the 2006 and 2008 Public Health Management Corporation's Southeastern Pennsylvania Household Health Surveys. Evaluating the potential role residential segregation has in offsetting medical discrimination, we compare the GWR results to tract data from the 2005-2009 American Community Survey. Through this comparison, we find that the effects of medical discrimination on self-rated health are weaker in magnitude in areas that are mostly minority. However, evidence of direct health benefits for minorities in segregated communities is inconclusive. Thus, while we cannot say living in segregated neighborhoods leads to better minority health, the sting of medical discrimination can be weaker in these places. These results emphasize the importance of local variation, even within a city like Philadelphia, challenging the aspatial one-model-fits-all approach normally found in population studies.

  7. Morphology and antimony segregation of spangles on batch hot-dip galvanized coatings

    Science.gov (United States)

    Peng, Shu; Lu, Jintang; Che, Chunshan; Kong, Gang; Xu, Qiaoyu

    2010-06-01

    Spangles produced by batch hot-dip galvanizing process have a rougher surface and a greater surface segregation of alloying element compared with those in continuous hot-dip galvanizing line (CGL), owing to the cooling rate of the former is much smaller than that of the later. Therefore, typical spangles on a batch hot-dipped Zn-0.05Al-0.2Sb alloy coating were investigated. The chemical, morphological characterization and identification of the phases on the spangles were examined by scanning electron microscopy (SEM), backscattered electron imaging (BSE), atomic force microscopy (AFM), energy dispersive spectroscopy (EDS) and X-ray diffraction analysis (XRD). The results showed that the coating surface usually exhibited three kinds of spangles: shiny, feathery and dull spangle, of which extensively antimony surface segregation was detected. The nature of precipitate on the coating surface was identified as β-Sb 3Zn 4, The precipitated β-Sb 3Zn 4 particles distributed randomly on the shiny spangle surface, both β-Sb 3Zn 4 particles and dentritic segregation of antimony dispersed in the dendritic secondary arm spacings of the feathery spangle and on the whole dull spangle surface. The dentritic segregation of antimony and precipitation of Sb 3Zn 4 compound are discussed by a proposed model.

  8. Morphology and antimony segregation of spangles on batch hot-dip galvanized coatings

    Energy Technology Data Exchange (ETDEWEB)

    Peng Shu, E-mail: shu.peng@mail.scut.edu.cn [School of Materials Science and Engineering, South China University of Technology, No. 371 Wushan Road, Tianhe District, Guangzhou 510640 (China); Lu Jintang; Che Chunshan; Kong Gang; Xu Qiaoyu [School of Materials Science and Engineering, South China University of Technology, No. 371 Wushan Road, Tianhe District, Guangzhou 510640 (China)

    2010-06-01

    Spangles produced by batch hot-dip galvanizing process have a rougher surface and a greater surface segregation of alloying element compared with those in continuous hot-dip galvanizing line (CGL), owing to the cooling rate of the former is much smaller than that of the later. Therefore, typical spangles on a batch hot-dipped Zn-0.05Al-0.2Sb alloy coating were investigated. The chemical, morphological characterization and identification of the phases on the spangles were examined by scanning electron microscopy (SEM), backscattered electron imaging (BSE), atomic force microscopy (AFM), energy dispersive spectroscopy (EDS) and X-ray diffraction analysis (XRD). The results showed that the coating surface usually exhibited three kinds of spangles: shiny, feathery and dull spangle, of which extensively antimony surface segregation was detected. The nature of precipitate on the coating surface was identified as {beta}-Sb{sub 3}Zn{sub 4}, The precipitated {beta}-Sb{sub 3}Zn{sub 4} particles distributed randomly on the shiny spangle surface, both {beta}-Sb{sub 3}Zn{sub 4} particles and dentritic segregation of antimony dispersed in the dendritic secondary arm spacings of the feathery spangle and on the whole dull spangle surface. The dentritic segregation of antimony and precipitation of Sb{sub 3}Zn{sub 4} compound are discussed by a proposed model.

  9. Using Group Counseling to Improve the Attendance of Elementary School Students with High Rates of Absenteeism: An Action Research Study

    Science.gov (United States)

    Webb-Landman, Eleanor

    2012-01-01

    The foundations of academic and social learning are laid in the early years of school, and attendance is critical to school success. However, research suggests that chronic absenteeism is a significant problem at the elementary school level (Chang & Romero, 2008; Romero & Lee, 2007). This paper presents the results of an action research…

  10. An Analysis of New Small High Schools' On-Time Graduation Rates in New York City

    Science.gov (United States)

    Dudley, Nathan

    2017-01-01

    Beginning in 2002, with the election of Mayor Michael Bloomberg, New York City's Department of Education undertook an unprecedented overhaul of the largest school district in the United States. Over the next 10 years the Department of Education closed more than 25 large, underperforming high schools, and created almost 200 new, small high schools,…

  11. A Comprehensive Partnership Approach Increasing High School Graduation Rates and College Enrollment of Urban Economically Disadvantaged Youth

    Science.gov (United States)

    Morgan, Yvette; Sinatra, Richard; Eschenauer, Robert

    2015-01-01

    Described is a 4-year model of a Gaining Early Awareness and Readiness for Undergraduate Program (GEAR UP) offered to 294 academically and economically disadvantaged students and their parents during in- and out-of-school time activities through partnerships forged with school personnel and community-based agencies. In an urban high school where…

  12. Trends in High School Dropout and Completion Rates in the United States: 2013. Compendium Report. NCES 2016-117

    Science.gov (United States)

    McFarland, Joel; Stark, Patrick; Cui, Jiashan

    2016-01-01

    Dropping out of high school is related to a number of negative outcomes. For example, the median income of persons ages 18 through 67 who had not completed high school was roughly $26,000 in 2013. By comparison, the median income of persons ages 18 through 67 who completed their education with at least a high school credential (i.e., a regular…

  13. Illness absenteeism rates in primary and secondary schools in 2013-2014 in England: was there any impact of vaccinating children of primary-school age against influenza?

    Science.gov (United States)

    Green, H K; Brousseau, N; Andrews, N; Selby, L; Pebody, R

    2016-09-09

    A phased introduction of routine influenza vaccination of healthy children was recommended in the UK in 2012, with the aim of protecting both vaccinated children and the wider population through reducing transmission. In the first year of the programme in 2013-2014, 4- to 11-year-olds were targeted in pilot areas across England. This study assesses if this was associated with school absenteeism, an important societal burden of influenza. During the spring 2014 term when influenza predominantly circulated, the proportion of absence sessions due to illness was compared between vaccination pilot and non-pilot areas for primary schools (to measure overall impact) and secondary schools (to measure indirect impact). A linear multilevel regression model was applied, adjusting for clustering within schools and potential school-level confounders, including deprivation, past absenteeism, and ethnicity. Low levels of influenza activity were reported in the community in 2013-2014. Primary schools in pilot areas had a significantly adjusted decrease in illness absenteeism of 0·05% relative to non-pilot schools; equivalent to an average of 4 days per school. In secondary schools, there was no significant indirect impact of being located in a pilot area on illness absenteeism. These insights can be used in conjunction with routine healthcare surveillance data to evaluate the full benefits of such a programme.

  14. Blood cell interactions and segregation in flow.

    Science.gov (United States)

    Munn, Lance L; Dupin, Michael M

    2008-04-01

    For more than a century, pioneering researchers have been using novel experimental and computational approaches to probe the mysteries of blood flow. Thanks to their efforts, we know that blood cells generally prefer to migrate to the axis of flow, that red and white cells segregate in flow, and that cell deformability and their tendency to reversibly aggregate contribute to the non-Newtonian nature of this unique fluid. All of these properties have beneficial physiological consequences, allowing blood to perform a variety of critical functions. Our current understanding of these unusual flow properties of blood have been made possible by the ingenuity and diligence of a number of researchers, including Harry Goldsmith, who developed novel technologies to visualize and quantify the flow of blood at the level of individual cells. Here we summarize efforts in our lab to continue this tradition and to further our understanding of how blood cells interact with each other and with the blood vessel wall.

  15. Centromeric heterochromatin: the primordial segregation machine.

    Science.gov (United States)

    Bloom, Kerry S

    2014-01-01

    Centromeres are specialized domains of heterochromatin that provide the foundation for the kinetochore. Centromeric heterochromatin is characterized by specific histone modifications, a centromere-specific histone H3 variant (CENP-A), and the enrichment of cohesin, condensin, and topoisomerase II. Centromere DNA varies orders of magnitude in size from 125 bp (budding yeast) to several megabases (human). In metaphase, sister kinetochores on the surface of replicated chromosomes face away from each other, where they establish microtubule attachment and bi-orientation. Despite the disparity in centromere size, the distance between separated sister kinetochores is remarkably conserved (approximately 1 μm) throughout phylogeny. The centromere functions as a molecular spring that resists microtubule-based extensional forces in mitosis. This review explores the physical properties of DNA in order to understand how the molecular spring is built and how it contributes to the fidelity of chromosome segregation.

  16. Radiation-induced segregation in model alloys

    Science.gov (United States)

    Ezawa, T.; Wakai, E.; Oshima, R.

    2000-12-01

    The dependence of the size factor of solutes on radiation-induced segregation (RIS) was studied. Ni-Si, Ni-Co, Ni-Cu, Ni-Mn, Ni-Pd, and Ni-Nb binary solid solution alloys were irradiated with electrons in a high voltage electron microscope at the same irradiation conditions. A focused beam and a grain boundary were utilized to generate a flow of point defects to cause RIS. From the concentration profile obtained by an energy dispersive X-ray analysis, the amount of RIS was calculated. The amount of RIS decreased as the size of the solute increased up to about 10%. However, as the size increased further, the amount of RIS increased. This result shows that RIS is not simply determined by the size effect rule.

  17. Figure-ground segregation in a recurrent network architecture

    NARCIS (Netherlands)

    Lamme, V.A.F.; Roelfsema, P.R.; Spekreijse, H.; Bosch, H.

    2002-01-01

    Proposes a model of how the visual brain segregate textured scenes into figures and background. During texture segregation, locations where the properties of texture elements change abruptly are assigned to boundaries, whereas image regions that are relatively homogeneous are grouped together

  18. Figure-ground segregation in a recurrent network architecture

    NARCIS (Netherlands)

    Roelfsema, Pieter R.; Lamme, Victor A. F.; Spekreijse, Henk; Bosch, Holger

    2002-01-01

    Here we propose a model of how the visual brain segregates textured scenes into figures and background. During texture segregation, locations where the properties of texture elements change abruptly are assigned to boundaries, whereas image regions that are relatively homogeneous are grouped

  19. Seeing Race: Teaching Residential Segregation with the Racial Dot Map

    Science.gov (United States)

    Seguin, Charles; Nierobisz, Annette; Kozlowski, Karen Phelan

    2017-01-01

    Students commonly hold erroneous notions of a "post-racial" world and individualistic worldviews that discount the role of structure in social outcomes. Jointly, these two preconceived beliefs can be powerful barriers to effective teaching of racial segregation: Students may be skeptical that racial segregation continues to exist, and…

  20. A new principle of figure-ground segregation : The accentuation

    NARCIS (Netherlands)

    Pinna, Baingio; Reeves, Adam; Koenderink, Jan; van Doorn, Andrea; Deiana, Katia

    2018-01-01

    The problem of perceptual organization was studied by Gestalt psychologists in terms of figure-ground segregation. In this paper we explore a new principle of figure-ground segregation: accentuation. We demonstrate the effectiveness of accentuation relative to other Gestalt principles, and also

  1. The Emergence of Gender Segregation in Toddler Playgroups.

    Science.gov (United States)

    Serbin, Lisa A.; And Others

    1994-01-01

    A naturalistic study of toddler playgroups examined factors that might encourage gender segregation. Results revealed that play in same-sex contexts facilitates social interaction, whereas in mixed-sex contexts, play leads to passive social relations. Toddlers who segregated were more behaviorally sex-typed. Preferences for sex-typed toys did not…

  2. Monte Carlo simulations of adsorption-induced segregation

    DEFF Research Database (Denmark)

    Christoffersen, Ebbe; Stoltze, Per; Nørskov, Jens Kehlet

    2002-01-01

    Through the use of Monte Carlo simulations we study the effect of adsorption-induced segregation. From the bulk composition, degree of dispersion and the partial pressure of the gas phase species we calculate the surface composition of bimetallic alloys. We show that both segregation and adsorption...

  3. 7 CFR 58.332 - Segregation of raw material.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Segregation of raw material. 58.332 Section 58.332... Specifications for Dairy Plants Approved for USDA Inspection and Grading Service 1 Operations and Operating Procedures § 58.332 Segregation of raw material. The milk and cream received at the dairy plant shall meet...

  4. Reverberation impairs brainstem temporal representations of voiced vowel sounds: challenging periodicity-tagged segregation of competing speech in rooms

    Directory of Open Access Journals (Sweden)

    Mark eSayles

    2015-01-01

    Full Text Available The auditory system typically processes information from concurrently active sound sources (e.g., two voices speaking at once, in the presence of multiple delayed, attenuated and distorted sound-wave reflections (reverberation. Brainstem circuits help segregate these complex acoustic mixtures into auditory objects. Psychophysical studies demonstrate a strong interaction between reverberation and fundamental-frequency (F0 modulation, leading to impaired segregation of competing vowels when segregation is on the basis of F0 differences. Neurophysiological studies of complex-sound segregation have concentrated on sounds with steady F0s, in anechoic environments. However, F0 modulation and reverberation are quasi-ubiquitous.We examine the ability of 129 single units in the ventral cochlear nucleus of the anesthetized guinea pig to segregate the concurrent synthetic vowel sounds /a/ and /i/, based on temporal discharge patterns under closed-field conditions. We address the effects of added real-room reverberation, F0 modulation, and the interaction of these two factors, on brainstem neural segregation of voiced speech sounds. A firing-rate representation of single-vowels’ spectral envelopes is robust to the combination of F0 modulation and reverberation: local firing-rate maxima and minima across the tonotopic array code vowel-formant structure. However, single-vowel F0-related periodicity information in shuffled inter-spike interval distributions is significantly degraded in the combined presence of reverberation and F0 modulation. Hence, segregation of double-vowels’ spectral energy into two streams (corresponding to the two vowels, on the basis of temporal discharge patterns, is impaired by reverberation; specifically when F0 is modulated. All unit types (primary-like, chopper, onset are similarly affected. These results offer neurophysiological insights to perceptual organization of complex acoustic scenes under realistically challenging

  5. The association between social networks and self-rated risk of HIV infection among secondary school students in Moshi Municipality, Tanzania

    DEFF Research Database (Denmark)

    Lyimo, Elizabeth; Todd, Jim; Richey, Lisa Ann

    2013-01-01

    This study describes the social networks of secondary school students in Moshi Municipality, and their association with self-rated risk of human immunodeficiency virus (HIV) infection. A cross-sectional analytical study was conducted among 300 students aged 15–24 years in 5 secondary schools...... participation in bonding and bridging social networks and self-rated HIV risk behavior. More participants participated in bonding networks (72%) than in bridging networks (29%). Participation in bridging networks was greater among females (25%) than males (12%, p 

  6. Improvement in dry active waste segregation and processing

    International Nuclear Information System (INIS)

    Hillmer, T.P.; Anderson, K.D.; Dahlen, D.E.

    1989-01-01

    At the Palo Verde Nuclear Generating Station (PVNGS) the majority of dry active waste (DAW) volume reduction activities are performed in the site's new DAW processing and storage facility. This facility houses an interim storage area for a five year volume of compacted DAW, a shredder/compactor, and a DAW segregation area. The DAW segregation program locates and separates non-radioactive and reusable materials from DAW generated at the three unit PVNGS site. This program has saved more than 24,000 cubic feet of burial space and has reclaimed more than $1,000,000 worth of materials. Palo Verde has made numerous changes to the DAW segregation program since its inception. To ensure that the DAW segregation program remained cost effective and in compliance with applicable regulatory guidance, segregation techniques were revised and new equipment was evaluated and procured. This paper details that effort and summarizes the operational data that has been collected

  7. The Struggle against Separate and Unequal Schools: Middle Class Mexican Americans and the Desegregation Campaign in Texas, 1929-1957.

    Science.gov (United States)

    San Miguel, Guadalupe, Jr.

    1983-01-01

    Despite the efforts of Mexican American groups, such as the League of United Latin American Citizens and the G.I. Forum, and court orders to end segregation, schools in Texas continued to segregate Mexican American children. The political liberalism of these groups kept them from developing effective strategies against segregation. (IS)

  8. Modeling solute segregation during the solidification of γ-phase U-Mo alloys

    Energy Technology Data Exchange (ETDEWEB)

    Steiner, M.A., E-mail: mas4cw@virginia.edu [University of Virginia, Material Science and Engineering, 395 McCormick Rd, Charlottesville, VA 22904 (United States); Garlea, E. [Y-12 National Security Complex, Oak Ridge, TN 37831 (United States); Agnew, S.R. [University of Virginia, Material Science and Engineering, 395 McCormick Rd, Charlottesville, VA 22904 (United States)

    2016-06-15

    Using first principles calculations, it is demonstrated that solute segregation during U-Mo solidification can be modeled using the classic Brody-Fleming limited diffusion framework. The necessary supporting equations specific to the U-Mo alloy, along with careful verification of the assumptions underpinning the Brody-Fleming model are developed, allowing for concentration profile predictions as a function of alloy composition and cooling rate. The resulting model is compared to experimental solute concentration profiles, showing excellent agreement. Combined with complementary modeling of dendritic feature sizes, the solute segregation model can be used to predict the complete microstructural state of individual U-Mo volume elements based upon cooling rates, informing ideal processing routes.

  9. Racial residential segregation, socioeconomic disparities, and the White-Black survival gap

    Science.gov (United States)

    Duffy, Erin; Mendelsohn, Joshua; Escarce, José J.

    2018-01-01

    Objective To evaluate the association between racial residential segregation, a prominent manifestation of systemic racism, and the White-Black survival gap in a contemporary cohort of adults, and to assess the extent to which socioeconomic inequality explains this association. Design This was a cross sectional study of White and Black men and women aged 35–75 living in 102 large US Core Based Statistical Areas. The main outcome was the White-Black survival gap. We used 2009–2013 CDC mortality data for Black and White men and women to calculate age-, sex- and race adjusted White and Black mortality rates. We measured segregation using the Dissimilarity index, obtained from the Manhattan Institute. We used the 2009–2013 American Community Survey to define indicators of socioeconomic inequality. We estimated the CBSA-level White–Black gap in probability of survival using sequential linear regression models accounting for the CBSA dissimilarity index and race-specific socioeconomic indicators. Results Black men and women had a 14% and 9% lower probability of survival from age 35 to 75 than their white counterparts. Residential segregation was strongly associated with the survival gap, and this relationship was partly, but not fully, explained by socioeconomic inequality. At the lowest observed level of segregation, and with the Black socioeconomic status (SES) assumed to be at the White SES level scenario, the survival gap is essentially eliminated. Conclusion White-Black differences in survival remain wide notwithstanding public health efforts to improve life expectancy and initiatives to reduce health disparities. Eliminating racial residential segregation and bringing Black socioeconomic status (SES) to White SES levels would eliminate the White-Black survival gap. PMID:29474451

  10. Racial residential segregation, socioeconomic disparities, and the White-Black survival gap.

    Directory of Open Access Journals (Sweden)

    Ioana Popescu

    Full Text Available To evaluate the association between racial residential segregation, a prominent manifestation of systemic racism, and the White-Black survival gap in a contemporary cohort of adults, and to assess the extent to which socioeconomic inequality explains this association.This was a cross sectional study of White and Black men and women aged 35-75 living in 102 large US Core Based Statistical Areas. The main outcome was the White-Black survival gap. We used 2009-2013 CDC mortality data for Black and White men and women to calculate age-, sex- and race adjusted White and Black mortality rates. We measured segregation using the Dissimilarity index, obtained from the Manhattan Institute. We used the 2009-2013 American Community Survey to define indicators of socioeconomic inequality. We estimated the CBSA-level White-Black gap in probability of survival using sequential linear regression models accounting for the CBSA dissimilarity index and race-specific socioeconomic indicators.Black men and women had a 14% and 9% lower probability of survival from age 35 to 75 than their white counterparts. Residential segregation was strongly associated with the survival gap, and this relationship was partly, but not fully, explained by socioeconomic inequality. At the lowest observed level of segregation, and with the Black socioeconomic status (SES assumed to be at the White SES level scenario, the survival gap is essentially eliminated.White-Black differences in survival remain wide notwithstanding public health efforts to improve life expectancy and initiatives to reduce health disparities. Eliminating racial residential segregation and bringing Black socioeconomic status (SES to White SES levels would eliminate the White-Black survival gap.

  11. Human Postmeiotic Segregation 2 Exhibits Biased Repair at Tetranucleotide Microsatellite Sequences

    OpenAIRE

    Shah, Sandeep N.; Eckert, Kristin A.

    2009-01-01

    The mismatch repair (MMR) system plays a major role in removing DNA polymerization errors, and loss of this pathway results in hereditary cancers characterized by microsatellite instability. We investigated microsatellite stability during DNA replication within human postmeiotic segregation 2 (hPMS2)–deficient and proficient human lymphoblastoid cell lines. Using a shuttle vector assay, we measured mutation rates at reporter cassettes containing defined mononucleotide, dinucleotide, and tetra...

  12. Segregated integration : recent trends in the Austrian gender division of labor

    OpenAIRE

    Kreimer, Margareta; Mora, Ricardo

    2013-01-01

    Using micro data from the Austrian Labor Force Survey, this paper explores how decreases in the gender differential in participation rates together with increasing differentials in the incidence of part-time jobs and stable or rising levels of occupational segregation by gender affect the gender division of labor. To so so, we propose an index for the gender division of labor based on the Mutual Information index. Our main results show that the gender division of labor is very sta...

  13. Development of Chemistry Triangle Oriented Module on Topic of Reaction Rate for Senior High School Level Grade XI Chemistry Learning.

    Science.gov (United States)

    Sari, D. R.; Hardeli; Bayharti

    2018-04-01

    This study aims to produce chemistry triangle oriented module on topic of reaction rate, and to reveal the validity and practicality level of the generated module. The type of research used is EducationalDesign Research (EDR) with development model is Plompmodel. This model consists of three phases, which are preliminary research, prototyping phase, and assessment phase. The instrument used in this research is questionnaire validity and practicality. The data of the research were analyzed by using Kappa Cohen formula. The chemistry triangle oriented module validation sheet was given to 5 validators consisting of 3 chemistry lecturers and 2 high school chemistry teachers, while the practicality sheet was given to 2 chemistry teachers, 6 students of SMAN 10 Padang grade XII MIA 5 on the small groupevaluation and 25 students of SMAN 10 Padang grade XII MIA 6 on the field test. Based on the questionnaire validity analysis, the validity level of the module is very high with the value of kappa moment 0.87. The level of practicality based on teacher questionnaire response is very high category with a kappa moment value 0.96. Based on the questionnaire of student responses on small group evaluation, the level of practicality is very high category with a kappa moment 0.81, and the practicality is very high category with kappa moment value 0.83 based on questionnaire of student response on field test.

  14. School-based assessments in high-stakes examinations in Bhutan: a question of trust? : exploring inconsistencies between external exam scores, school-based assessments, detailed teacher ratings, and student self-ratings

    NARCIS (Netherlands)

    Luyten, Johannes W.; Dolkar, Dechen

    2010-01-01

    This study explores the validity of school-based assessments when they serve to supplement scores on central tests in high-stakes examinations. The school-based continuous assessment (CA) marks are compared to the marks scored on the central written Bhutan Certificate of Secondary Education (BCSE)

  15. Trends in Algebra II Completion and Failure Rates for Students Entering Texas Public High Schools. REL 2018-289

    Science.gov (United States)

    Stoker, Ginger; Mellor, Lynn; Sullivan, Kate

    2018-01-01

    This study examines Algebra II completion and failure rates for students entering Texas public high schools from 2007/08 through 2014/15. This period spans the time when Texas students, beginning with the 2007/08 grade 9 cohort, were required to take four courses each in English, math (including Algebra II), science, and social studies (called the…

  16. Development and Initial Validation of the Student Rating of Environmental Stressors Scale: Stressors Faced by Students in Accelerated High School Curricula

    Science.gov (United States)

    Suldo, Shannon M.; Dedrick, Robert F.; Shaunessy-Dedrick, Elizabeth; Roth, Rachel A.; Ferron, John

    2015-01-01

    High school students in accelerated curricula face stressors beyond typical adolescent developmental challenges. The Student Rating of Environmental Stressors Scale (StRESS) is a self-report measure of environmental stressors appropriate for students in Advanced Placement (AP) and International Baccalaureate (IB) courses. We developed the StRESS…

  17. Taylor revisited: Gender segregation and division of labour in the ICT - sector (information and communication technology)

    DEFF Research Database (Denmark)

    Nygaard, Else

    2001-01-01

    Information and communication technology, division of labour, gender segregation, working conditions......Information and communication technology, division of labour, gender segregation, working conditions...

  18. Chromosome segregation analysis in human embryos obtained from couples involving male carriers of reciprocal or Robertsonian translocation.

    Directory of Open Access Journals (Sweden)

    Ahmet Yilmaz

    Full Text Available The objective of this study was to investigate the frequency and type of chromosome segregation patterns in cleavage stage embryos obtained from male carriers of Robertsonian (ROB and reciprocal (REC translocations undergoing preimplantation genetic diagnosis (PGD at our reproductive center. We used FISH to analyze chromosome segregation in 308 day 3 cleavage stage embryos obtained from 26 patients. The percentage of embryos consistent with normal or balanced segregation (55.1% vs. 27.1% and clinical pregnancy (62.5% vs. 19.2% rates were higher in ROB than the REC translocation carriers. Involvement of non-acrocentric chromosome(s or terminal breakpoint(s in reciprocal translocations was associated with an increase in the percent of embryos consistent with adjacent 1 but with a decrease in 3∶1 segregation. Similar results were obtained in the analysis of nontransferred embryos donated for research. 3∶1 segregation was the most frequent segregation type in both day 3 (31% and spare (35% embryos obtained from carriers of t(11;22(q23;q11, the only non-random REC with the same breakpoint reported in a large number of unrelated families mainly identified by the birth of a child with derivative chromosome 22. These results suggest that chromosome segregation patterns in day 3 and nontransferred embryos obtained from male translocation carriers vary with the type of translocation and involvement of acrocentric chromosome(s or terminal breakpoint(s. These results should be helpful in estimating reproductive success in translocation carriers undergoing PGD.

  19. Texture segregation, surface representation and figure-ground separation.

    Science.gov (United States)

    Grossberg, S; Pessoa, L

    1998-09-01

    A widespread view is that most texture segregation can be accounted for by differences in the spatial frequency content of texture regions. Evidence from both psychophysical and physiological studies indicate, however, that beyond these early filtering stages, there are stages of 3-D boundary segmentation and surface representation that are used to segregate textures. Chromatic segregation of element-arrangement patterns--as studied by Beck and colleagues--cannot be completely explained by the filtering mechanisms previously employed to account for achromatic segregation. An element arrangement pattern is composed of two types of elements that are arranged differently in different image regions (e.g. vertically on top and diagonally on the bottom). FACADE theory mechanisms that have previously been used to explain data about 3-D vision and figure-ground separation are here used to simulate chromatic texture segregation data, including data with equiluminant elements on dark or light homogeneous backgrounds, or backgrounds composed of vertical and horizontal dark or light stripes, or horizontal notched stripes. These data include the fact that segregation of patterns composed of red and blue squares decreases with increasing luminance of the interspaces. Asymmetric segregation properties under 3-D viewing conditions with the equiluminant elements close or far are also simulated. Two key model properties are a spatial impenetrability property that inhibits boundary grouping across regions with non-collinear texture elements and a boundary-surface consistency property that uses feedback between boundary and surface representations to eliminate spurious boundary groupings and separate figures from their backgrounds.

  20. Segregation in ternary alloys: an interplay of driving forces

    International Nuclear Information System (INIS)

    Luyten, J.; Helfensteyn, S.; Creemers, C.

    2003-01-01

    Monte Carlo (MC) simulations combined with the constant bond energy (CBE) model are set up to explore and understand the general segregation behaviour in ternary alloys as a function of composition and more in particular the segregation to Cu-Ni-Al (1 0 0) surfaces. Besides its simplicity, allowing swift simulations, which are necessary for a first general survey over all possible compositions, one of the advantages of the CBE model lies in the possibility to clearly identify the different driving forces for segregation. All simulations are performed in the Grand Canonical Ensemble, using a new algorithm to determine the chemical potential of the components. Notwithstanding the simplicity of the CBE model, one extra feature is evidenced: depending on the values of the interatomic interaction parameters, in some regions of the ternary diagram, a single solid solution becomes thermodynamically unstable, leading to demixing into two conjugate phases. The simulations are first done for three hypothetical systems that are however representative for real alloy systems. The three systems are characterised by different sets of interatomic interaction parameters. These extensive simulations over the entire composition range of the ternary alloy yield a 'topographical' segregation map, showing distinct regions where different species segregate. These distinct domains originate from a variable interplay between the driving forces for segregation and attractive/repulsive interactions in the bulk of the alloy. The results on these hypothetical systems are very helpful for a better understanding of the segregation behaviour in Cu-Ni-Al and other ternary alloys