Conducting a longitudinal survey of overnight travel : methods and preliminary findings.
DOT National Transportation Integrated Search
2015-06-01
This report summarizes the implementation and initial results of the Longitudinal : Study of Overnight Travel (LSOT), conducted monthly between February 2013 and : February 2014 using an online survey instrument developed by researchers at the : Univ...
ERIC Educational Resources Information Center
Hergenrather, Kenneth C.; Zeglin, Robert J.; McGuire-Kuletz, Maureen; Rhodes, Scott D.
2015-01-01
Purpose: To explore employment as a social determinant of health through examining the relationship between employment status and physical health. Method: The authors explored the causal relationship between employment status and physical health through conducting a systematic review of 22 longitudinal studies conducted in Finland, France, the…
The Influence of Elective Surgery on Functional Health in Veterans with PTSD
2012-12-21
elective surgery in veterans with PTSD. Design : A longitudinal, mixed method, quasi-experimental, nonequivalent control group study was conducted...longitudinal, mixed method, quasi-experimental, nonequivalent control group study was conducted. Methods and Sample: Physical and mental health...Methods Procedures." In Research design : qualitative, quantitative , and mixed methods approaches, 203-226. Thousand Oaks, Calif.: Sage Publications
ERIC Educational Resources Information Center
Hergenrather, Kenneth C.; Zeglin, Robert J.; McGuire-Kuletz, Maureen; Rhodes, Scott D.
2015-01-01
Purpose: To explore employment as a social determinant of health through examining the relationship between employment status and mental health. Method: The authors conducted a systematic review of 48 longitudinal studies conducted in Australia, Canada, Croatia, Germany, Ireland, Israel, the Netherlands, Norway, United Kingdom, and United States…
Conduct Problems, IQ, and Household Chaos: A Longitudinal Multi-Informant Study
ERIC Educational Resources Information Center
Deater-Deckard, Kirby; Mullineaux, Paula Y.; Beekman, Charles; Petrill, Stephen A.; Schatschneider, Chris; Thompson, Lee A.
2009-01-01
Background: We tested the hypothesis that household chaos would be associated with lower child IQ and more child conduct problems concurrently and longitudinally over two years while controlling for housing conditions, parent education/IQ, literacy environment, parental warmth/negativity, and stressful events. Methods: The sample included 302…
Longitudinal Models of Socio-Economic Status: Impact on Positive Parenting Behaviors
ERIC Educational Resources Information Center
Azad, Gazi; Blacher, Jan; Marcoulides, George
2014-01-01
Parenting research is frequently conducted without a thorough examination of socio-economic characteristics. In this study, longitudinal observations of positive parenting were conducted across six time points. Participants were 219 mothers of children with and without developmental delays. Mothers' positive parenting increased during early and…
Longitudinal Research with Sexual Assault Survivors: A Methodological Review
ERIC Educational Resources Information Center
Campbell, Rebecca; Sprague, Heather Brown; Cottrill, Sara; Sullivan, Cris M.
2011-01-01
Longitudinal research designs are relatively rare in the academic literature on rape and sexual assault despite their tremendous methodological rigor and scientific utility. In the interest of promoting wider use of such methods, we conducted a methodological review of projects that have used prospective longitudinal designs to study the…
Modeling a Longitudinal Relational Research Data Systems
ERIC Educational Resources Information Center
Olsen, Michelle D. Hunt
2010-01-01
A study was conducted to propose a research-based model for a longitudinal data research system that addressed recommendations from a synthesis of literature related to: (1) needs reported by the U.S. Department of Education, (2) the twelve mandatory elements that define federally approved state longitudinal data systems (SLDS), (3) the…
Returning findings within longitudinal cohort studies: the 1958 birth cohort as an exemplar.
Wallace, Susan E; Walker, Neil M; Elliott, Jane
2014-01-01
Population-based, prospective longitudinal cohort studies are considering the issues surrounding returning findings to individuals as a result of genomic and other medical research studies. While guidance is being developed for clinical settings, the process is less clear for those conducting longitudinal research. This paper discusses work conducted on behalf of The UK Cohort and Longitudinal Study Enhancement Resource programme (CLOSER) to examine consent requirements, process considerations and specific examples of potential findings in the context of the 1958 British Birth cohort. Beyond deciding which findings to return, there are questions of whether re-consent is needed and the possible impact on the study, how the feedback process will be managed, and what resources are needed to support that process. Recommendations are made for actions a cohort study should consider taking when making vital decisions regarding returning findings. Any decisions need to be context-specific, arrived at transparently, communicated clearly, and in the best interests of both the participants and the study.
ERIC Educational Resources Information Center
Preston, Kathleen Suzanne Johnson; Parral, Skye N.; Gottfried, Allen W.; Oliver, Pamella H.; Gottfried, Adele Eskeles; Ibrahim, Sirena M.; Delany, Danielle
2015-01-01
A psychometric analysis was conducted using the nominal response model under the item response theory framework to construct the Positive Family Relationships scale. Using data from the Fullerton Longitudinal Study, this scale was constructed within a long-term longitudinal framework spanning middle childhood through adolescence. Items tapping…
Scaling relation of the anomalous Hall effect in (Ga,Mn)As
NASA Astrophysics Data System (ADS)
Glunk, M.; Daeubler, J.; Schoch, W.; Sauer, R.; Limmer, W.
2009-09-01
We present magnetotransport studies performed on an extended set of (Ga,Mn)As samples at 4.2 K with longitudinal conductivities σxx ranging from the low-conductivity to the high-conductivity regime. The anomalous Hall conductivity σxy(AH) is extracted from the measured longitudinal and Hall resistivities. A transition from σxy(AH)=20Ω-1cm-1 due to the Berry phase effect in the high-conductivity regime to a scaling relation σxy(AH)∝σxx1.6 for low-conductivity samples is observed. This scaling relation is consistent with a recently developed unified theory of the anomalous Hall effect in the framework of the Keldysh formalism. It turns out to be independent of crystallographic orientation, growth conditions, Mn concentration, and strain, and can therefore be considered universal for low-conductivity (Ga,Mn)As. The relation plays a crucial role when deriving values of the hole concentration from magnetotransport measurements in low-conductivity (Ga,Mn)As. In addition, the hole diffusion constants for the high-conductivity samples are determined from the measured longitudinal conductivities.
RECRUITMENT AND RETENTION ISSUES FOR A LONGITUDINAL STUDY OF CHILDREN'S ENVIRONMENTAL HEALTH
A better understanding of the most effective recruitment techniques and retention strategies for longitudinal, community-based, children's environmental health studies is needed. A series of 18 focus groups were conducted across the U.S. in February 2003. Pregnant women and exp...
The effect of compressive viscosity and thermal conduction on the longitudinal MHD waves
NASA Astrophysics Data System (ADS)
Bahari, K.; Shahhosaini, N.
2018-05-01
longitudinal Magnetohydrodynamic (MHD) oscillations have been studied in a slowly cooling coronal loop, in the presence of thermal conduction and compressive viscosity, in the linear MHD approximation. WKB method has been used to solve the governing equations. In the leading order approximation the dispersion relation has been obtained, and using the first order approximation the time dependent amplitude has been determined. Cooling causes the oscillations to amplify and damping mechanisms are more efficient in hot loops. In cool loops the oscillation amplitude increases with time but in hot loops the oscillation amplitude decreases with time. Our conclusion is that in hot loops the efficiency of the compressive viscosity in damping longitudinal waves is comparable to that of the thermal conduction.
The effect of compressive viscosity and thermal conduction on the longitudinal MHD waves
NASA Astrophysics Data System (ADS)
Bahari, K.; Shahhosaini, N.
2018-07-01
Longitudinal magnetohydrodynamic (MHD) oscillations have been studied in a slowly cooling coronal loop, in the presence of thermal conduction and compressive viscosity, in the linear MHD approximation. The WKB method has been used to solve the governing equations. In the leading order approximation the dispersion relation has been obtained, and using the first-order approximation the time-dependent amplitude has been determined. Cooling causes the oscillations to amplify and damping mechanisms are more efficient in hot loops. In cool loops the oscillation amplitude increases with time but in hot loops the oscillation amplitude decreases with time. Our conclusion is that in hot loops the efficiency of the compressive viscosity in damping longitudinal waves is comparable to that of the thermal conduction.
Flexitime in an Army Medical Center.
1981-04-01
and Costigan (1973) conducted a longitudinal study of employee responses to the four day week in a medium-sized pharmaceutical company. The patterns...New York, New York, 1979. Nord, W.R. and Costigan, R. Worker adjustment to the four - day week : a longitudinal study. Journal of Applied Psychology, 58
NASA Technical Reports Server (NTRS)
Washburn, K. E.; Gloss, B. B.
1976-01-01
Force and moment data studies were conducted to determine the effect of wing-tip dihedral on the longitudinal and lateral aerodynamic characteristics of a supersonic cruise fighter configuration. Oil flow studies were also performed to investigate the model surface flow. Three models were tested: a flat (0 deg dihedral) wing tip, a dihedral, and an anhedral wing tip. The tests were conducted at the NASA Langley high-speed 7- by 10-foot wind tunnel.
Continuing and Ceasing Leisure Activities in Later Life: A Longitudinal Study
ERIC Educational Resources Information Center
Strain, Laurel A.; Grabusic, Carmen C.; Searle, Mark S.; Dunn, Nicole J.
2002-01-01
Purpose: This study examined changes in leisure activities of older adults over an 8-year period, and associated sociodemographic and health characteristics. Design and Methods: Data were from a longitudinal study conducted in Winnipeg, Manitoba, Canada; 380 respondents were interviewed in-person in both 1985 and 1993. Changes in ten specific…
Homeschooling Education: Longitudinal Study of Methods, Materials, and Curricula
ERIC Educational Resources Information Center
Hanna, Linda G.
2012-01-01
In a comprehensive study of two-hundred fifty homeschooling families in urban, rural and suburban areas of the Commonwealth of Pennsylvania, the researcher examined all aspects of the instruction, materials and curricula employed by the families in a ten-year longitudinal study from 1998 through 2008. The researcher conducted interviews and…
The US EPA has completed field data collections from a series of longitudinal particulate matter (PM) exposure panel field studies. These studies were conducted in Baltimore, Maryland (1998), Fresno, California (1999), and Research Triangle Park (RTP), North Carolina (2000-2001) ...
Conduct problems, IQ, and household chaos: a longitudinal multi-informant study
Deater-Deckard, Kirby; Mullineaux, Paula Y.; Beekman, Charles; Petrill, Stephen A.; Schatschneider, Chris; Thompson, Lee A.
2010-01-01
Background We tested the hypothesis that household chaos would be associated with lower child IQ and more child conduct problems concurrently and longitudinally over two years while controlling for housing conditions, parent education/IQ, literacy environment, parental warmth/negativity, and stressful events. Methods The sample included 302 families with same-sex twins (58% female) in Kindergarten/1st grade at the first assessment. Parents’ and observers’ ratings were gathered, with some collected over a two-year period. Results Chaos varied widely. There was substantial mother–father agreement and longitudinal stability. Chaos covaried with poorer housing conditions, lower parental education/IQ, poorer home literacy environment, higher stress, higher negativity and lower warmth. Chaos statistically predicted lower IQ and more conduct problems, beyond the effects of other home environment factors. Conclusions Even with other home environment factors controlled, higher levels of chaos were linked concurrently with lower child IQ, and concurrently and longitudinally with more child conduct problems. Parent self-reported chaos represents an important aspect of housing and family functioning, with respect to children’s cognitive and behavioral functioning. PMID:19527431
An Epidemiological Model of Transition and Postschool Outcomes
ERIC Educational Resources Information Center
Flexer, Robert W.; Daviso, Alfred W., III; Baer, Robert M.; Queen, Rachel McMahan; Meindl, Richard S.
2011-01-01
This longitudinal transition study was conducted in collaboration with teachers who interviewed students who graduated from 177 school districts in a Great Lakes state. Special education students were interviewed at exit and 1 year following graduation using a survey based on the National Longitudinal Transition Study. The data were analyzed using…
A Longitudinal Study of Middle and Secondary Level Science Textbook Vocabulary Loads
ERIC Educational Resources Information Center
Groves, Fred H.
2016-01-01
Middle and secondary science textbooks have long been a primary support for instruction, often leading to heavy emphasis on domain-specific vocabulary. A longitudinal study was conducted to compare vocabulary loads of science textbooks published since 2010 to results of two previous studies going back to 1983. In each study, textbooks chosen…
Retention strategies in longitudinal studies with emerging adults.
Hanna, Kathleen M; Scott, Linda L; Schmidt, Karen K
2014-01-01
The purpose of this report was to describe retention strategies that were useful and those that were not in a longitudinal study of emerging adults. A longitudinal study examining the transition to young adulthood among emerging adults with type 1 diabetes, which had success in retention, provided the context for describing retention strategies. A challenge in longitudinally designed studies is retention of participants because the loss decreases power for statistical analysis. Given that emerging adulthood is a period of instability, retention is particularly challenging among this population. However, longitudinal studies are the best way to understand developmental changes, and it is also important to increase our knowledge of health outcomes during emerging adulthood. Retention strategies used in the study are described, including promoting a positive relationship with participants, maintaining contact with participants, having a study staff with good interpersonal skills, using incentives, conveying respect for participants, and using user-friendly data collection. Useful strategies to promote a positive relationship included sending cards and newsletters to participants, maintaining consistency of contact person, and expressing appreciation for participant's time and effort. Useful strategies for maintaining contact with participants included obtaining contact information at every data collection point, maintaining birth dates and chart numbers in tracking databases, monitoring returned mail, and using Web search engines. Other useful strategies were providing incentives to participants, employing staff with good interpersonal skills, providing participants with choices when appropriate, and using user-friendly data collection. One strategy, using contests, was not found useful. Despite the challenges of conducting longitudinally designed studies with emerging adults, multiple retention strategies can be used that are useful to retention. It is feasible to conduct longitudinal studies with emerging adults despite the challenges.
Veronese, Nicola; Facchini, Silvia; Stubbs, Brendon; Luchini, Claudio; Solmi, Marco; Manzato, Enzo; Sergi, Giuseppe; Maggi, Stefania; Cosco, Theodore; Fontana, Luigi
2017-01-01
Whilst obesity is associated with a higher risk of cognitive impairment, the influence of weight loss on cognitive function in obese/overweight people is equivocal. We conducted a meta-analysis of randomized controlled trials (RCTs) and longitudinal studies evaluating the influence of voluntary weight loss on cognitive function in obese/overweight individuals. Articles were acquired from a systematic search of major databases from inception till 01/2016. A random effect meta-analysis of weight loss interventions (diet, physical activity, bariatric surgery) on different cognitive domains (memory, attention, executive functions, language and motor speed) was conducted. Twenty studies (13 longitudinal studies=551 participants; 7 RCTs=328 treated vs. 140 controls) were included. Weight loss was associated with a significant improvement in attention and memory in both longitudinal studies and RCTs, whereas executive function and language improved in longitudinal and RCT studies, respectively. In conclusion, intentional weight loss in obese/overweight people is associated with improvements in performance across various cognitive domains. Future adequately powered RCTs are required to confirm/refute these findings. Copyright © 2016 Elsevier Ltd. All rights reserved.
NASA Technical Reports Server (NTRS)
Nairn, John A.
1992-01-01
A combined analytical and experimental study was conducted to analyze microcracking, microcrack-induced delamination, and longitudinal splitting in polymer matrix composites. Strain energy release rates, calculated by a variational analysis, were used in a failure criterion to predict microcracking. Predictions and test results were compared for static, fatigue, and cyclic thermal loading. The longitudinal splitting analysis accounted for the effects of fiber bridging. Test data are analyzed and compared for longitudinal splitting and delamination under mixed-mode loading. This study emphasizes the importance of using fracture mechanics analyses to understand the complex failure processes that govern composite strength and life.
ERIC Educational Resources Information Center
Wu, Chin-Chin; Chiang, Chung-Hsin
2014-01-01
To explore the different developmental trajectories of social-communicative skills in children with autism and typically developing infants, two longitudinal studies were conducted. In Study 1, we examined the developmental sequence of social-communicative skills in 26 typically developing infants when they were 9 months old and reexamined them…
ERIC Educational Resources Information Center
Hoopes, Janet L.
A longitudinal study was conducted to determine factors predicting successful adoptions before placement and to identify differences and similarities between adoptive and biological families. Data collected on both adopted children and on their adoptive families before placement was related to data collected on the same children and families 6…
ERIC Educational Resources Information Center
Maryland Univ., College Park. Maryland Longitudinal Study Steering Committee.
As part of the Maryland Longitudinal Study of 772 students entering the University of Maryland, College Park (UMCP) in the fall of 1980, a study was conducted to determine patterns of college student employment and profiles of students in different employment categories. Findings included the following: (1) approximately 40% of students were…
ERIC Educational Resources Information Center
Rees, Charlotte E.; Wearn, Andy M.; Vnuk, Anna K.; Sato, Toshio J.
2009-01-01
Although studies have begun to shed light on medical students' attitudes towards peer physical examination (PPE), they have been conducted at single sites, and have generally not examined changes in medical students' attitudes over time. Employing both cross-sectional and longitudinal designs, the current study examines medical students' attitudes…
ERIC Educational Resources Information Center
Negru-Subtirica, Oana; Pop, Eleonora Ioana; Luyckx, Koen; Dezutter, Jessie; Steger, Michael F.
2016-01-01
Identity formation in adolescence is closely linked to searching for and acquiring meaning in one's life. To date little is known about the manner in which these 2 constructs may be related in this developmental stage. In order to shed more light on their longitudinal links, we conducted a 3-wave longitudinal study, investigating how identity…
Maternal Attributions and Young Children's Conduct Problems: A Longitudinal Study
ERIC Educational Resources Information Center
Wilson, Charlotte; Gardner, Frances; Burton, Jennifer; Leung, Sarah
2006-01-01
The association between negative maternal attributions and child conduct problems is well established in correlational studies. However, little is known about how these variables influence each other over time. The present study examined patterns of prediction over time between maternal attributions and pre-school conduct problems. Sixty mothers…
Pathways to an Engineering Career
ERIC Educational Resources Information Center
Pearson, Willie, Jr.; Miller, Jon D.
2012-01-01
Utilizing data from the 20-year record of the Longitudinal Study of American Youth (LSAY), this analysis uses a set of variables to predict employment in engineering for a national sample of adults aged 34 to 37. The LSAY is one of the longest longitudinal studies of the impact of secondary education and postsecondary education conducted in the…
Newspapers and Adult Understanding of Public Affairs: Two Longitudinal Community Studies.
ERIC Educational Resources Information Center
Tichenor, P. J.; And Others
Two longitudinal field studies of the process of information dissemination through newspapers were conducted on two different public affairs topics (regional planning and routing of a high voltage power line) in four communities to examine the role of newspapers in increasing levels of conflict and in creating greater levels of awareness and…
A Longitudinal Study of Laterality Expression and Teacher Evaluation of Elementary School Children
ERIC Educational Resources Information Center
Van Camp, Sarah S.
1978-01-01
A three-year longitudinal study conducted to assess the incidence of mixed laterality in elementary school children showed that thirty-seven percent of the eighty-two subjects had mixed laterality. No relationship was found between perceptual motor and academic achievement as measured by teacher ratings and mixed laterality. (MF)
ERIC Educational Resources Information Center
Kochel, Karen P.; Miller, Cindy Faith; Updegraff, Kimberly A.; Ladd, Gary W.; Kochenderfer-Ladd, Becky
2012-01-01
An accruing body of evidence supports associations between self-perceived gender typicality and peer relationship difficulties; however, researchers have yet to evaluate peers' perceptions of problem behaviors to gain insight into the social correlates of gender typicality. A short-term longitudinal study was conducted to evaluate associations…
High Risk for Schizophrenia from Conception to Young Adulthood.
ERIC Educational Resources Information Center
King, Suzanne
1990-01-01
Summarizes and critiques Asarnow's 1988 review of 24 longitudinal studies identifying environmental factors and individual vulnerability important to development of schizophrenia. Found Asarnow's analysis well conducted but summary should have addressed longitudinal research design. Concludes that identifiable behavior and family interaction…
Smith, Sven; Ferguson, Chris; Beaver, Kevin
Despite several decades of research, little scholarly consensus has emerged regarding the role of violent video games in the development of youth psychopathology or crime. The current study employed the Avon Longitudinal Study of Parents and Children longitudinal dataset to examine the impact of the shooter game genre ownership in childhood on later adolescent conduct disorder and criminal behavior. Multivariate Poisson regressions with the robust estimator correlation matrix were performed comparing effects of independent and confounding variables. Results revealed that early childhood mental health symptoms at age seven related to ADHD, depression and early conduct disorder predicted criminal behavior at age fifteen. Male gender also predicted criminal behavior at age fifteen. However, exposure to shooter games did not predict adolescent conduct disorder or criminal behavior. We have found support that suggests that the role of violent video games in the development of youth psychopathology or crime is very little if any. Lack of a relationship between exposure to shooter games and later conduct and criminal behavior problems may be understood within the context of the Catalyst Model. Copyright © 2018 Elsevier Ltd. All rights reserved.
Neuromapping: Inflight Evaluation of Cognition and Adaptability
NASA Technical Reports Server (NTRS)
Kofman, I. S.; De Dios, Y. E.; Lawrence, K.; Schade, A.; Reschke, M. F.; Bloomberg, J. J.; Wood, S. J.; Mulavara, A. P.; Seidle, R. D.
2016-01-01
In consideration of the health and performance of crewmembers during flight and postflight, we are conducting a controlled prospective longitudinal study to investigate the effects of spaceflight on the extent, longevity and neural bases of sensorimotor, cognitive, and neural changes. Previous studies investigating sensorimotor adaptation to the microgravity environment longitudinally inflight have shown reduction in the ability to perform complex dual tasks. In this study we perform a series of tests investigating the longitudinal effects of adaptation to the microgravity environment and how it affects spatial cognition, manual visuo-motor adaption and dual tasking.
Salis, Katie Lee; Bernard, Kristin; Black, Sarah R; Dougherty, Lea R; Klein, Daniel
2016-09-01
Previous literature indicates that both hypoactivity and hyperactivity of the HPA axis may be related to conduct disorder and externalizing behaviors in young children. Using a longitudinal sample of 283 typically-developing children, the current study examined both the concurrent and the longitudinal association between HPA functioning and externalizing behavior problems, such as conduct problems. Diurnal cortisol rhythms and externalizing problems were assessed at ages 6 and 9. Results suggest that concurrent HPA functioning is not significantly related to externalizing behavior at ages 6 or 9. However, more blunted cortisol rhythms at age 6 (less change across the day from morning to evening) predicted a greater increase in externalizing behavior between age 6 and age 9 than did steeper cortisol rhythms. Further analyses revealed that this association was driven by conduct problems and aggressive behavior, rather than attention problems. The relationship between HPA functioning and subsequent externalizing behavior in children adds to the limited longitudinal work on this topic, suggesting that the association changes over time. These results may serve to clarify the inconsistencies in the cross-sectional literature, particularly with respect to young school-age children. Copyright © 2016 Elsevier Ltd. All rights reserved.
Salis, Katie Lee; Bernard, Kristin; Black, Sarah R.; Dougherty, Lea R.; Klein, Daniel
2017-01-01
Previous literature indicates that both hypoactivity and hyperactivity of the HPA axis may be related to conduct disorder and externalizing behaviors in young children. Using a longitudinal sample of 283 typically-developing children, the current study examined both the concurrent and the longitudinal association between HPA functioning and externalizing behavior problems, such as conduct problems. Diurnal cortisol rhythms and externalizing problems were assessed at ages 6 and 9. Results suggest that concurrent HPA functioning is not significantly related to externalizing behavior at ages 6 or 9. However, more blunted cortisol rhythms at age 6 (less change across the day from morning to evening) predicted a greater increase in externalizing behavior between age 6 and age 9 than did steeper cortisol rhythms. Further analyses revealed that this association was driven by conduct problems and aggressive behavior, rather than attention problems. The relationship between HPA functioning and subsequent externalizing behavior in children adds to the limited longitudinal work on this topic, suggesting that the association changes over time. These results may serve to clarify the inconsistencies in the cross-sectional literature, particularly with respect to young school-age children. PMID:27266968
ERIC Educational Resources Information Center
Girardet, Céline; Berger, Jean-Louis
2018-01-01
Two studies were conducted to investigate the evolution of 71 Swiss vocational teachers' classroom management as a result of the inputs of a teacher education program, and to identify the factors that encouraged or impeded teacher change. Study 1 consisted of a longitudinal survey, and Study 2 of interviews. Longitudinal analyses were performed…
Development of Working Memory and Performance in Arithmetic: A Longitudinal Study with Children
ERIC Educational Resources Information Center
López, Magdalena
2014-01-01
Introduction: This study has aimed to investigate the relationship between the development of working memory and performance on arithmetic activities. Method: We conducted a 3-year longitudinal study of a sample of 90 children, that was followed during the first, second and third year of primary school. All children were tested on measures of WM…
Wagner, Matthias O; Bös, Klaus; Jekauc, Darko; Karger, Claudia; Mewes, Nadine; Oberger, Jennifer; Reimers, Anne K; Schlenker, Lars; Worth, Annette; Woll, Alexander
2014-10-01
The Motorik-Modul (MoMo) Longitudinal Study aims to contribute to long-term improvement in the health of German children and adolescents by focusing on: (i) the development of physical fitness and physical activity (including period effects); (ii) the individual and physical/social environmental determinants of the development of physical fitness and physical activity; and (iii) the impact of physical fitness and physical activity on the development of physical and mental health. The MoMo Longitudinal Study began with a nationwide representative sample of 4529 children and adolescents who ranged in age from 4-17 years at the study baseline (2003-2006). The first survey wave of the MoMo Longitudinal Study was conducted between 2009 and 2012, with two subsequent survey waves to be conducted between 2014 and 2016 and 2018 and 2020, respectively. The MoMo Longitudinal Study includes a physical fitness test profile, a physical activity questionnaire, and subjective and objective measures of health from the German Health Interview and Examination Survey (KiGGS). Data access is provided on request (alexander.woll@kit.edu). For further information, including a complete list of publications please visit www.motorik-modul.de. Published by Oxford University Press on behalf of the International Epidemiological Association © The Author 2013; all rights reserved.
ERIC Educational Resources Information Center
Wenger, G. Clare; Burholt, Vanessa
2004-01-01
The Bangor Longitudinal Study of Aging (BLSA), conducted in rural Wales from 1979 to 1999, followed a cohort of survivors from more than 500 people over 20 years. Using both quantitative and qualitative data from the study, the factors associated with increases and decreases in loneliness and social isolation were identified. The study was based…
Concurrent and Longitudinal Predictors of Calculation Skills in Preschoolers
ERIC Educational Resources Information Center
Tobia, Valentina; Bonifacci, Paola; Marzocchi, Gian Marco
2016-01-01
Early calculation abilities in preschoolers are predictive of mathematics achievement in subsequent grades (e.g., Jordan et al. 2009). Two studies were conducted to evaluate concurrent and longitudinal predictors of early calculation skills. In the first study, 102 preschoolers (57.8% female; mean age?=?60.57?±?8.66 months) were given vocabulary,…
"I Feel So Confused": A Longitudinal Study of Young Adolescents' Change in Self-Esteem
ERIC Educational Resources Information Center
Booth, Margaret Zoller; Curran, Erin
2010-01-01
This paper investigates the growth of early adolescent self-esteem and self-concept as students progress through the middle level years (sixth through eighth grade). Based on mixed method longitudinal research conducted from 2004 to 2007, the study's findings suggest that this sample of 104 urban students' self-esteem changed most significantly…
A Longitudinal Study of Narrative Development in Children and Adolescents with Down Syndrome
ERIC Educational Resources Information Center
Cleave, Patricia; Bird, Elizabeth Kay-Raining; Czutrin, Rachael; Smith, Lindsey
2012-01-01
The present study examined narrative development in children and adolescents with Down syndrome longitudinally. Narratives were collected from 32 children and adolescents with Down syndrome three times over a 1-year period. Both micro- and macrolevel analyses were conducted. Significant growth over the 1-year period was seen in semantic complexity…
ERIC Educational Resources Information Center
Tourangeau, Karen; Brick, Mike; Byrne, Lauren; Le, Thanh; Nord, Christine; West, Jerry; Hausken, Elvira Germino
2005-01-01
This methodology report provides technical information about the development, design, and conduct of the third grade data collection of the Early Childhood Longitudinal Study, Kindergarten Class of 1998-99 (ECLS-K). Detailed information on the development of the instruments, sample design, data collection methods, data preparation and editing,…
ERIC Educational Resources Information Center
Lonigan, Christopher J.; Allan, Darcey M.; Phillips, Beth M.
2017-01-01
There is strong evidence that self-regulatory processes are linked to early academic skills, both concurrently and longitudinally. The majority of extant longitudinal studies, however, have been conducted using autoregressive techniques that may not accurately model change across time. The purpose of this study was to examine the unique…
ERIC Educational Resources Information Center
Bieg, Sonja; Reindl, Marion; Dresel, Markus
2017-01-01
The present work broadens previous research on students' mastery goals and intrinsic motivation by exploring their reciprocal effects using a longitudinal approach. To this end, a study using four measurement points was conducted during 10 weeks of one semester. The sample comprised 1156 students enrolled in psychology courses at a medium-sized…
ERIC Educational Resources Information Center
Hammond, Cathy; Drew, Sam F.; Withington, Cairen; Griffith, Cathy; Swiger, Caroline M.; Mobley, Catherine; Sharp, Julia L.; Stringfield, Samuel C.; Stipanovic, Natalie; Daugherty, Lindsay
2013-01-01
This Technical Appendix discusses how researchers from the National Research Center for Career and Technical Education (NRCCTE) conducted the five-year longitudinal study of South Carolina's Personal Pathway to Success initiative, which was authorized by the state's Education and Economic Development Act (EEDA) in 2005, and how they defined and…
A Longitudinal Follow-Up Study of Affect in Children and Adults with Cornelia de Lange Syndrome
ERIC Educational Resources Information Center
Nelson, Lisa; Moss, Jo; Oliver, Chris
2014-01-01
Studies of individuals with Cornelia de Lange syndrome (CdLS) have described changes in mood and behavior with age, although no empirical or longitudinal studies have been conducted. Caregivers of individuals with CdLS (N = 67), cri du chat syndrome (CdCS; N = 42), and Fragile X syndrome (FXS; N = 142) completed the Mood, Interest and Pleasure…
Tense Marking in the English Narrative Retells of Dual Language Preschoolers
ERIC Educational Resources Information Center
Gusewski, Svenja; Rojas, Raul
2017-01-01
Purpose: This longitudinal study investigated the emergence of English tense marking in young (Spanish-English) dual language learners (DLLs) over 4 consecutive academic semesters, addressing the need for longitudinal data on typical acquisition trajectories of English in DLL preschoolers. Method: Language sample analysis was conducted on 139…
The Generalized Multilevel Facets Model for Longitudinal Data
ERIC Educational Resources Information Center
Hung, Lai-Fa; Wang, Wen-Chung
2012-01-01
In the human sciences, ability tests or psychological inventories are often repeatedly conducted to measure growth. Standard item response models do not take into account possible autocorrelation in longitudinal data. In this study, the authors propose an item response model to account for autocorrelation. The proposed three-level model consists…
Longitudinal Adult Practical Problem-Solving: 1983, 1993, 2003
ERIC Educational Resources Information Center
Haught, Patricia A.; Walls, Richard T.
2007-01-01
A 20-year longitudinal study was conducted to examine adult performance on practical problems. Effects of independent variables of age, education, and administration time were assessed on solutions generated and quality points earned. Younger adults generated more solutions than other adults in 1983, 1993, and 2003. Both younger and middle adults…
ERIC Educational Resources Information Center
Shin, Hyeonsook
2010-01-01
This study was conducted to examine the role of child depression in the relations between deficits in competence and aggression by replicating and extending the study by Cole et al. (1996). In a two-wave longitudinal study, 6th-grade children (n = 329) completed self-report measures of three domains of competence (i.e. social, academic,…
ERIC Educational Resources Information Center
Arango, Lisa Lewis; Kurtines, William M.; Montgomery, Marilyn J.; Ritchie, Rachel
2008-01-01
The study reported in this article, a Multi-Stage Longitudinal Comparative Design Stage II evaluation conducted as a planned preliminary efficacy evaluation (psychometric evaluation of measures, short-term controlled outcome studies, etc.) of the Changing Lives Program (CLP), provided evidence for the reliability and validity of the qualitative…
ERIC Educational Resources Information Center
Wine, Jennifer; Janson, Natasha; Siegel, Peter; Bennett, Christopher
2013-01-01
This report documents the methodological procedures and evaluations of the 2008/09 Baccalaureate and Beyond Longitudinal Study (B&B:08/09). RTI, with the assistance of MPR, conducted B&B:08/09 for the National Center for Education Statistics (NCES) of the U.S. Department of Education. Chapter 1 describes the background, legislative…
Changes in Weight over the School Year and Summer Vacation: Results of a 5-Year Longitudinal Study
ERIC Educational Resources Information Center
Moreno, Jennette P.; Johnston, Craig A.; Woehler, Deborah
2013-01-01
Background: Evidence suggests that children gain more weight during the summer months compared with the school year. To examine the impact of the school and summer environment on children's weight further, we conducted a 5-year longitudinal study examining changes in standardized BMI (zBMI) of students entering kindergarten. Methods: Heights and…
Violence Viewing and Adolescent Aggression: A Longitudinal Study.
ERIC Educational Resources Information Center
Viemero, Vappu
A longitudinal field study conducted in Turku, Finland, traced the development of aggression as a function of the viewing of violence by children from the ages of 7 and 9 to the ages of 15 and 17 to explore the connection between violence viewing and viewers' aggression, and to shed light on the question of causality. The 220 subjects, both male…
ERIC Educational Resources Information Center
Boger, Robert P.; Cunningham, Jo Lynn
An extensive longitudinal research effort conducted through the Early Childhood Research Center at Michigan State University focused on understanding the forces leading to positive social and emotional development during the preschool years. Because of the rather limited base which was available from other studies for launching such an effort,…
ERIC Educational Resources Information Center
Chen, Peiying; Wang, Ting
2015-01-01
This article presents findings of a longitudinal case study conducted at a Taiwanese high school from 2006 to 2010. This school participated in the 'High Scope Programme' (HSP), which was sponsored by the Taiwanese National Science Council to promote curricular innovation in science education. Utilising interview data with 11 participating…
ERIC Educational Resources Information Center
Riglin, Lucy; Frederickson, Norah; Shelton, Katherine H.; Rice, Frances
2013-01-01
This longitudinal study of adolescents in the first year of secondary school, examined the relationship between psychological functioning at the beginning of year 7 (mean age 11.25 years) with attainment at the end of year 7 (mean age 11.78 years). Depressive symptoms, school liking and conduct problems predicted lower attainment across time…
ERIC Educational Resources Information Center
Ogura, Tamiko
The development of and relationship between early language, symbolic play, sensorimotor skills, and social development were examined in a longitudinal study conducted in Japan with two young autistic males who were observed from the approximate ages of 2 to 4 years in clinic, day care, and home settings. One child acquired speech; the other did…
Long-Term Benefits of Full-Day Kindergarten: A Longitudinal Population-Based Study
ERIC Educational Resources Information Center
Brownell, M. D.; Nickel, N. C.; Chateau, D.; Martens, P. J.; Taylor, C.; Crockett, L.; Katz, A.; Sarkar, J.; Burland, E.; Goh, C. Y.
2015-01-01
In the first longitudinal, population-based study of full-day kindergarten (FDK) outcomes beyond primary school in Canada, we used linked administrative data to follow 15 kindergarten cohorts (n ranging from 112 to 736) up to grade 9. Provincial assessments conducted in grades 3, 7, and 8 and course marks and credits earned in grade 9 were…
The Stability of Genetic Determination from Age 2 to Age 9: A Longitudinal Twin Study.
ERIC Educational Resources Information Center
Lytton, Hugh; And Others
A longitudinal investigation of the social and cognitive development of male twins was conducted when twins were 2.5 years of age, and again when they were 8- to 10-years-old. This study was designed to re-examine the heritability of the traits studied at the earlier age and, thus, to address the question of the stability of genetic determination.…
Systematic review of the association between physical activity and burnout.
Naczenski, Lea M; Vries, Juriena D de; Hooff, Madelon L M van; Kompier, Michiel A J
2017-11-25
Burnout constitutes a health risk, and interventions are needed to reduce it. The aim of this study was to synthesize evidence regarding the relationship between physical activity and burnout by conducting a systematic review of longitudinal and intervention studies. A literature search resulted in the identification of a final set of ten studies: four longitudinal and six intervention studies. In separate analyses for each category, evidence was synthesized by extracting the study characteristics and assessing the methodological quality of each study. The strength of evidence was calculated with the standardized index of convergence (SIC). In longitudinal studies, we found moderately strong evidence (SIC (4) = -1) for a negative relationship between physical activity and the key component of burnout, i.e., exhaustion. We found strong evidence (SIC (6) = -0.86) for the effect of physical activity on reducing exhaustion in intervention studies. As only one study could be classified as a high quality study, these results of previous studies need to be interpreted with some caution. This systematic review suggests that physical activity constitutes an effective medium for the reduction of burnout. Although consistent evidence was found, there is a lack of high quality longitudinal and intervention studies considering the influence of physical activity on burnout. Therefore, future research should be conducted with the aim to produce high quality studies, to develop a full picture of physical activity as a strategy to reduce burnout.
Relevance of Conduction Disorders in Bachmann's Bundle During Sinus Rhythm in Humans.
Teuwen, Christophe P; Yaksh, Ameeta; Lanters, Eva A H; Kik, Charles; van der Does, Lisette J M E; Knops, Paul; Taverne, Yannick J H J; van de Woestijne, Pieter C; Oei, Frans B S; Bekkers, Jos A; Bogers, Ad J J C; Allessie, Maurits A; de Groot, Natasja M S
2016-05-01
Bachmann's bundle (BB) is considered to be the main route of interatrial conduction and to play a role in development of atrial fibrillation (AF). The goals of this study are to characterize the presence of conduction disorders in BB during sinus rhythm and to study their relation with AF. High-resolution epicardial mapping (192 unipolar electrodes, interelectrode distance: 2 mm) of sinus rhythm was performed in 185 patients during coronary artery bypass surgery of whom 13 had a history of paroxysmal AF. Continuous rhythm monitoring was used to detect postoperative AF during the first 5 postoperative days. In 67% of the patients, BB was activated from right to left; in the remaining patients from right and middle (21%), right, central, and left (8%), or central (4%) site. Mean effective conduction velocity was 89 cm/s. Conduction block was present in most patients (75%; median 1.1%, range 0-12.8) and was higher in patients with paroxysmal AF compared with patients without a history of AF (3.2% versus 0.9%; P=0.03). A high amount of conduction block (>4%) was associated with de novo postoperative AF (P=0.02). Longitudinal lines of conduction block >10 mm were also associated with postoperative AF (P=0.04). BB may be activated through multiple directions, but the predominant route of conduction is from right to left. Conduction velocity across BB is around 90 cm/s. Conduction is blocked in both longitudinal and transverse direction in the majority of patients. Conduction disorders, particularly long lines of longitudinal conduction block, are more pronounced in patients with AF episodes. © 2016 American Heart Association, Inc.
The Reality of Longitudinal Data Collection: Locating Vanishing Veterans.
ERIC Educational Resources Information Center
Camara, Wayne J.; And Others
This paper investigates the utility of various procedures used to locate and interview veterans as part of a longitudinal research study being conducted for the Department of Defense. The populations are comprised of below entry aptitude standards males who entered the military during the late 1960s, and potentially ineligibles who entered between…
Computer-Based Learning of Neuroanatomy: A Longitudinal Study of Learning, Transfer, and Retention
ERIC Educational Resources Information Center
Chariker, Julia H.; Naaz, Farah; Pani, John R.
2011-01-01
A longitudinal experiment was conducted to evaluate the effectiveness of new methods for learning neuroanatomy with computer-based instruction. Using a three-dimensional graphical model of the human brain and sections derived from the model, tools for exploring neuroanatomy were developed to encourage "adaptive exploration". This is an…
ERIC Educational Resources Information Center
Evaluation and Training Inst., Los Angeles, CA.
Twenty-one California career-vocational educational articulation projects, commonly referred to as 2 + 2 partnerships, were jointly funded across the 1986-89 funding period and third-party evaluations were conducted in 1988-89. The longitudinal study examined the long-term effects of the original partnerships. Evaluators formed an advisory…
ERIC Educational Resources Information Center
Feinberg, Mark E.; Kan, Marni L.; Hetherington, E. Mavis
2007-01-01
This study addresses two limitations of coparenting research: first, little research on coparenting has been conducted with families of adolescents, and second, there is little understanding regarding the child and family contexts in which coparenting is most salient. The longitudinal relation of coparenting conflict to parenting and adolescent…
Longitudinal analysis of fishing behavior among Texas anglers (1990-2006)
Jiaying Lu; Michael A. Schuett; Nathan Wolber; Robert Ditton
2010-01-01
This study examined fishing participation and experience preferences of Texas anglers from a longitudinal perspective. Data were obtained from five independent statewide surveys of licensed Texas anglers conducted by Texas A and M University in 1990, 1994, 1998, 2002, and 2006. We observed the following changes between 1990 and 2006: 1) Fishing participation,...
The Use of Longitudinal Analysis to Identify More and Less Effective Schools.
ERIC Educational Resources Information Center
Goldberg, Zandra S.; Spartz, James L.
Three longitudinal studies of student achievement test data were conducted to examine the extent to which the variation in student achievement can be explained by differences in student background (including socioeconomic and prior achievement data) and school resources. This model assumes that achievement test performance may be predicted by…
Development of Internalization from Age 2 to 6: Longitudinal Stability and Links with Temperament.
ERIC Educational Resources Information Center
Coy, Katherine C.; Parrot, Tracie A.
This study examined relations between internalization of conduct rules and the temperamental quality of inhibitory control in 103 children followed from toddlerhood to early school age; and used recent methodological suggestions to obtain better estimates of stability to examine longitudinal continuity of internalization. Maternal reports of…
von Eye, Alexander; Mun, Eun Young; Bogat, G Anne
2008-03-01
This article reviews the premises of configural frequency analysis (CFA), including methods of choosing significance tests and base models, as well as protecting alpha, and discusses why CFA is a useful approach when conducting longitudinal person-oriented research. CFA operates at the manifest variable level. Longitudinal CFA seeks to identify those temporal patterns that stand out as more frequent (CFA types) or less frequent (CFA antitypes) than expected with reference to a base model. A base model that has been used frequently in CFA applications, prediction CFA, and a new base model, auto-association CFA, are discussed for analysis of cross-classifications of longitudinal data. The former base model takes the associations among predictors and among criteria into account. The latter takes the auto-associations among repeatedly observed variables into account. Application examples of each are given using data from a longitudinal study of domestic violence. It is demonstrated that CFA results are not redundant with results from log-linear modeling or multinomial regression and that, of these approaches, CFA shows particular utility when conducting person-oriented research.
Longitudinal Development of Hand Function in Children with Unilateral Cerebral Palsy
ERIC Educational Resources Information Center
Holmefur, Marie; Krumlinde-Sundholm, Lena; Bergstrom, Jakob; Eliasson, Ann-Christin
2010-01-01
Aim: The aim of this study was to describe how the usefulness of the hemiplegic hand develops in children with unilateral cerebral palsy (CP) aged between 18 months and 8 years. Method: A prospective longitudinal study of 43 children (22 males, 21 females) with unilateral CP was conducted. Inclusion age was 18 months to 5 years 4 months (mean 2y…
A Longitudinal Study of a 5th Grade Science Curriculum Based on the 5E Model
ERIC Educational Resources Information Center
Scott, Timothy P.; Schroeder, Carolyn; Tolson, Homer; Huang, Tse-Yang; Williams, Omah M.
2014-01-01
The Center for Mathematics and Science Education at Texas A&M University contracted with Region 4 Education Service Center (ESC) and a large, diverse school district to conduct a longitudinal study from 2005-2009. The state achievement test scores of 5th graders who were taught using a Grade 5 science textbook designed by Region 4 ESC were…
ERIC Educational Resources Information Center
Cleaver, Elizabeth; Ireland, Eleanor; Kerr, David; Lopes, Joana
2006-01-01
The Citizenship Education Longitudinal Study, conducted by the National Foundation for Education Research (NFER) on behalf of the Department for Education and Skills (DfES), aims to identify, measure and evaluate the extent to which effective practice in citizenship education develops in schools so that such practice can be promoted widely. The…
Vacuum chamber for containing particle beams
Harvey, A.
1985-11-26
A vacuum chamber for containing a charged particle beam in a rapidly changing magnetic environment comprises a ceramic pipe with conducting strips oriented along the longitudinal axis of the pipe and with circumferential conducting bands oriented perpendicular to the longitudinal axis but joined with a single longitudinal electrical connection. When both strips and bands are on the outside of the ceramic pipe, insulated from each other, a high-resistance conductive layer such as nickel can be coated on the inside of the pipe.
ERIC Educational Resources Information Center
Pedersen, Willy; Mastekaasa, Arne
2011-01-01
Research on teenage pregnancy and abortion has primarily focused on socio-economic disadvantage. However, a few studies suggest that risk of unwanted pregnancy is related to conduct disorder symptoms. We examined the relationship between level of conduct disorder symptoms at age 15 and subsequent pregnancy, child-birth and abortion. A…
Flowing together: a longitudinal study of collective efficacy and collective flow among workgroups.
Salanova, Marisa; Rodríguez-Sánchez, Alma M; Schaufeli, Wilmar B; Cifre, Eva
2014-01-01
The aim of this study is to extend the Channel Model of Flow (Csikszentmihalyi, 1975, 1990) at the collective level (workgroups) by including collective efficacy beliefs as a predictor of collective flow based on the Social Cognitive Theory (Bandura, 1997, 2001). A two-wave longitudinal lab study was conducted with 250 participants working in 52 small groups. Longitudinal results from Structural Equation Modeling with data aggregated at the group level showed, as expected, that collective efficacy beliefs predict collective flow over time, both being related reciprocally. Findings and their theoretical and practical implications in the light of Social Cognitive Theory are discussed.
Poirier, Martine; Déry, Michèle; Temcheff, Caroline E; Toupin, Jean; Verlaan, Pierrette; Lemelin, Jean-Pascal
2016-07-01
Youth with conduct problems (CP) may experience high rates of depressive symptoms (DS). However, little is known about the direction of the longitudinal associations between CP and DS in this specific population. Although girls with CP appear at greater risk than boys for presenting comorbid depression, empirical research on gender differences in these associations is even sparser. The current study used autoregressive latent trajectory models to compare four perspectives with hypotheses regarding the longitudinal associations between CP and DS, while taking into account the evolution of both problems. We also examined gender differences in the longitudinal associations. A total of 345 children (40.6 % female) presenting with a high level of CP in early elementary school (mean age at study inception = 8.52; SD = .94) were evaluated annually over a four-year period (5 measurement time points). The results revealed that CP and DS were quite stable over time. Moreover, CP and DS showed strong covariation at each measurement time point, but only one significant positive cross-lagged association between the two processes, indicating that higher levels of DS at time 3 were associated with higher levels of CP 1 year later. No differences were observed in the longitudinal associations between CP and DS in boys and girls. Given the comorbidity and stability of CP and DS, these findings suggest that DS should be systematically evaluated among children with early clinically significant CP, and treatment plans should include interventions aimed at both CP and DS among children who present with both types of problems.
ERIC Educational Resources Information Center
Deacon, S. Hélène; Kieffer, Michael
2018-01-01
The authors tested theoretically driven predictions as to the ways in which syntactic awareness, or awareness of word order within sentences, might contribute to reading comprehension, the end goal of reading development and instruction. They conducted a longitudinal study of 100 English-speaking children followed from Grade 3 to 4. Children…
ERIC Educational Resources Information Center
Sandler, Irwin N.; And Others
1994-01-01
Examined stress and coping symptoms of 258 children whose parents were divorced. Found that, in the cross-sectional model, avoidance coping partially mediated the relations between negative events and symptoms; while active coping moderated between negative events and conduct problems. In the longitudinal model, significant negative paths were…
ERIC Educational Resources Information Center
National Centre for Vocational Education Research (NCVER), 2012
2012-01-01
The Longitudinal Surveys of Australian Youth (LSAY) program studies the progress of several groups of young Australians as they move from school into post-secondary education and work. Since 2003, the LSAY program has been integrated with the Programme for International Student Assessment (PISA) conducted by the Organisation for Economic…
ERIC Educational Resources Information Center
Ingels, Steven J.; Pratt, Daniel J.; Jewell, Donna M.; Mattox, Tiffany; Dalton, Ben; Rosen, Jeffrey; Lauff, Erich; Hill, Jason
2012-01-01
This report describes the methodologies and results of the third follow-up Education Longitudinal Study of 2002 (ELS:2002/12) field test which was conducted in the summer of 2011. The field test report is divided into six chapters: (1) Introduction; (2) Field Test Survey Design and Preparation; (3) Data Collection Procedures and Results; (4) Field…
ERIC Educational Resources Information Center
Rosen, Jules; Stiehl, Emily M.; Mittal, Vikas; Leana, Carrie R.
2011-01-01
Purpose: Studies of certified nursing assistant (CNA) turnover in nursing homes are typically cross-sectional and include full-time and part-time workers. We conducted a longitudinal study to evaluate the job factors and work attitudes associated with just full-time staying or leaving. For those who did not stay, we assessed reasons for leaving…
Tudur Smith, Catrin; Gueyffier, François; Kolamunnage‐Dona, Ruwanthi
2017-01-01
Background Joint modelling of longitudinal and time‐to‐event data is often preferred over separate longitudinal or time‐to‐event analyses as it can account for study dropout, error in longitudinally measured covariates, and correlation between longitudinal and time‐to‐event outcomes. The joint modelling literature focuses mainly on the analysis of single studies with no methods currently available for the meta‐analysis of joint model estimates from multiple studies. Methods We propose a 2‐stage method for meta‐analysis of joint model estimates. These methods are applied to the INDANA dataset to combine joint model estimates of systolic blood pressure with time to death, time to myocardial infarction, and time to stroke. Results are compared to meta‐analyses of separate longitudinal or time‐to‐event models. A simulation study is conducted to contrast separate versus joint analyses over a range of scenarios. Results Using the real dataset, similar results were obtained by using the separate and joint analyses. However, the simulation study indicated a benefit of use of joint rather than separate methods in a meta‐analytic setting where association exists between the longitudinal and time‐to‐event outcomes. Conclusions Where evidence of association between longitudinal and time‐to‐event outcomes exists, results from joint models over standalone analyses should be pooled in 2‐stage meta‐analyses. PMID:29250814
The Australian Longitudinal Study on Women's Health: Using Focus Groups to Inform Recruitment
2016-01-01
Background Recruitment and retention of participants to large-scale, longitudinal studies can be a challenge, particularly when trying to target young women. Qualitative inquiries with members of the target population can prove valuable in assisting with the development of effective recruiting techniques. Researchers in the current study made use of focus group methodology to identify how to encourage young women aged 18-23 to participate in a national cohort online survey. Objective Our objectives were to gain insight into how to encourage young women to participate in a large-scale, longitudinal health survey, as well as to evaluate the survey instrument and mode of administration. Methods The Australian Longitudinal Study on Women’s Health used focus group methodology to learn how to encourage young women to participate in a large-scale, longitudinal Web-based health survey and to evaluate the survey instrument and mode of administration. Nineteen groups, involving 75 women aged 18-23 years, were held in remote, regional, and urban areas of New South Wales and Queensland. Results Focus groups were held in 2 stages, with discussions lasting from 19 minutes to over 1 hour. The focus groups allowed concord to be reached regarding survey promotion using social media, why personal information was needed, strategies to ensure confidentiality, how best to ask sensitive questions, and survey design for ease of completion. Recruitment into the focus groups proved difficult: the groups varied in size between 1 and 8 participants, with the majority conducted with 2 participants. Conclusions Intense recruitment efforts and variation in final focus group numbers highlights the “hard to reach” character of young women. However, the benefits of conducting focus group discussions as a preparatory stage to the recruitment of a large cohort for a longitudinal Web-based health survey were upheld. PMID:26902160
Tavener, Meredith; Chojenta, Catherine; Loxton, Deborah
2016-07-15
Objectives and importance of study: The purpose of this study was to illustrate how qualitative free-text comments, collected within the context of a health survey, represent a rich data source for understanding specific phenomena. Work conducted with data from the Australian Longitudinal Study on Women's Health (ALSWH) was used to demonstrate the breadth and depth of qualitative information that can be collected. The ALSWH has been collecting data on women's health since 1996, and represents a unique opportunity for understanding lived experiences across the lifecourse. A multiple case study design was used to demonstrate the techniques that researchers have used to manage free-text qualitative comments collected by the ALSWH. Eleven projects conducted using free-text comments are discussed according to the method of analysis. These methods include coding (both inductively and deductively), longitudinal analyses and software-based analyses. This work shows that free-text comments are a data resource in their own right, and have the potential to provide rich and valuable information about a wide variety of topics.
The impact of sedimentary anisotropy on solute mixing in stacked scour-pool structures
NASA Astrophysics Data System (ADS)
Bennett, Jeremy P.; Haslauer, Claus P.; Cirpka, Olaf A.
2017-04-01
The spatial variability of hydraulic conductivity is known to have a strong impact on solute spreading and mixing. In most investigations, its local anisotropy has been neglected. Recent studies have shown that spatially varying orientation in sedimentary anisotropy can lead to twisting flow enhancing transverse mixing, but most of these studies used geologically implausible geometries. We use an object-based approach to generate stacked scour-pool structures with either isotropic or anisotropic filling which are typically reported in glacial outwash deposits. We analyze how spatially variable isotropic conductivity and variation of internal anisotropy in these features impacts transverse plume deformation and both longitudinal and transverse spreading and mixing. In five test cases, either the scalar values of conductivity or the spatial orientation of its anisotropy is varied between the scour-pool structures. Based on 100 random configurations, we compare the variability of velocity components, stretching and folding metrics, advective travel-time distributions, one and two-particle statistics in advective-dispersive transport, and the flux-related dilution indices for steady state advective-dispersive transport among the five test cases. Variation in the orientation of internal anisotropy causes strong variability in the lateral velocity components, which leads to deformation in transverse directions and enhances transverse mixing, whereas it hardly affects the variability of the longitudinal velocity component and thus longitudinal spreading and mixing. The latter is controlled by the spatial variability in the scalar values of hydraulic conductivity. Our results demonstrate that sedimentary anisotropy is important for transverse mixing, whereas it may be neglected when considering longitudinal spreading and mixing.
Systematic review of the association between physical activity and burnout
Naczenski, Lea M.; de Vries, Juriena D.; van Hooff, Madelon L. M.; Kompier, Michiel A. J.
2017-01-01
Objective: Burnout constitutes a health risk, and interventions are needed to reduce it. The aim of this study was to synthesize evidence regarding the relationship between physical activity and burnout by conducting a systematic review of longitudinal and intervention studies. Methods: A literature search resulted in the identification of a final set of ten studies: four longitudinal and six intervention studies. In separate analyses for each category, evidence was synthesized by extracting the study characteristics and assessing the methodological quality of each study. The strength of evidence was calculated with the standardized index of convergence (SIC). Results: In longitudinal studies, we found moderately strong evidence (SIC (4) = -1) for a negative relationship between physical activity and the key component of burnout, i.e., exhaustion. We found strong evidence (SIC (6) = -0.86) for the effect of physical activity on reducing exhaustion in intervention studies. As only one study could be classified as a high quality study, these results of previous studies need to be interpreted with some caution. Conclusions: This systematic review suggests that physical activity constitutes an effective medium for the reduction of burnout. Although consistent evidence was found, there is a lack of high quality longitudinal and intervention studies considering the influence of physical activity on burnout. Therefore, future research should be conducted with the aim to produce high quality studies, to develop a full picture of physical activity as a strategy to reduce burnout. PMID:28993574
Peer Deviance, Parenting and Disruptive Behavior among Young Girls
ERIC Educational Resources Information Center
Miller, Shari; Loeber, Rolf; Hipwell, Alison
2009-01-01
This study examined concurrent and longitudinal associations between peer deviance, parenting practices, and conduct and oppositional problems among young girls ages 7 and 8. Participants were 588 African American and European American girls who were part of a population-based study of the development of conduct problems and delinquency among…
Wang, Ming-Te; Kenny, Sarah
2013-01-01
This study used cross-lagged modeling to examine reciprocal relations between maternal and paternal harsh verbal discipline and adolescents' conduct problems and depressive symptoms. Data were from a sample of 976 two-parent families and their children (51% males; 54% European American, 40% African American). Mothers' and fathers' harsh verbal discipline at age 13 predicted an increase in adolescent conduct problems and depressive symptoms between ages 13 and 14. A child effect was also present, with adolescent misconduct at age 13 predicting increases in mothers' and fathers' harsh verbal discipline between ages 13 and 14. Furthermore, maternal and paternal warmth did not moderate the longitudinal associations between mothers' and fathers' use of harsh verbal discipline and adolescent conduct problems and depressive symptoms. PMID:24001259
A longitudinal analysis of the impact of childhood stress on weight status among Chinese youth.
Tanenbaum, H C; Li, Y; Felicitas-Perkins, J Q; Zhang, M; Palmer, P; Johnson, C A; Xie, B
2017-05-01
Limited research has explored longitudinal impact of stress on negative health outcomes, including overweight and obesity in Asian societies. Using data from a longitudinal school-based health promotion study conducted in Wuhan, China from 1999 to 2004, this study investigated the longitudinal effects of childhood stress exposure, including stressors related to school, family, peers, violence and health on overweight, and obesity risk during the transition to adolescence among 2179 Chinese adolescents. Results showed that health stressors were consistently related to higher BMI Z score for both boys and girls baseline, it also predicted higher likelihood of overweight status over time for girls. This finding highlights a particularly challenging time period for girls, suggesting a particular challenging time they face at the intersection of puberty and demanding school environment.
ERIC Educational Resources Information Center
Bethel, James; Green, James L.; Nord, Christine; Kalton, Graham; West, Jerry
2005-01-01
This report is Volume 2 of the methodology report that provides information about the development, design, and conduct of the 9-month data collection of the Early Childhood Longitudinal Study, Birth Cohort (ECLS-B). This volume begins with a brief overview of the ECLS-B, but focuses on the sample design, calculation of response rates, development…
NASA Astrophysics Data System (ADS)
Ujevic, Sebastian; Mendoza, Michel
2010-07-01
We propose numerical simulations of longitudinal magnetoconductance through a finite antidot lattice located inside an open quantum dot with a magnetic field applied perpendicular to the plane. The system is connected to reservoirs using quantum point contacts. We discuss the relationship between the longitudinal magnetoconductance and the generation of transversal couplings between the induced open quantum dots in the system. The system presents longitudinal magnetoconductance maps with crossovers (between transversal bands) and closings (longitudinal decoupling) of fundamental quantum states related to the open quantum dots induced by the antidot lattice. A relationship is observed between the distribution of antidots and the formed conductance bands, allowing a systematic follow up of the bands as a function of the applied magnetic field and quantum point-contact width. We observed a high conductance intensity [between n and (n+1) quantum of conductance, n=1,2,… ] in the regions of crossover and closing of states. This suggests transversal couplings between the induced open quantum dots of the system that can be modulated by varying both the antidots potential and the quantum point-contact width. A new continuous channel (not expected) is induced by the variation in the contact width and generate Fano resonances in the conductance. These resonances can be manipulated by the applied magnetic field.
Schnettler, Berta; Miranda, Horacio; Miranda-Zapata, Edgardo; Salinas-Oñate, Natalia; Grunert, Klaus G; Lobos, Germán; Sepúlveda, José; Orellana, Ligia; Hueche, Clementina; Bonilla, Héctor
2017-06-01
This study examined longitudinal measurement invariance in the Satisfaction with Food-related Life (SWFL) scale using follow-up data from university students. We examined this measure of the SWFL in different groups of students, separated by various characteristics. Through non-probabilistic longitudinal sampling, 114 university students (65.8% female, mean age: 22.5) completed the SWFL questionnaire three times, over intervals of approximately one year. Confirmatory factor analysis was used to examine longitudinal measurement invariance. Two types of analysis were conducted: first, a longitudinal invariance by time, and second, a multigroup longitudinal invariance by sex, age, socio-economic status and place of residence during the study period. Results showed that the 3-item version of the SWFL exhibited strong longitudinal invariance (equal factor loadings and equal indicator intercepts). Longitudinal multigroup invariance analysis also showed that the 3-item version of the SWFL displays strong invariance by socio-economic status and place of residence during the study period over time. Nevertheless, it was only possible to demonstrate equivalence of the longitudinal factor structure among students of both sexes, and among those older and younger than 22 years. Generally, these findings suggest that the SWFL scale has satisfactory psychometric properties for longitudinal measurement invariance in university students with similar characteristics as the students that participated in this research. It is also possible to suggest that satisfaction with food-related life is associated with sex and age. Copyright © 2017 Elsevier Ltd. All rights reserved.
The Effect of Teacher Training on the Learning Styles of Prospective Teachers of Social Studies
ERIC Educational Resources Information Center
Özdemir, Nevin; Kesten, Alper; Iskin, Pinar
2017-01-01
The purpose of this study is to examine the effects of four-year-long undergraduate education on the learning styles of prospective teachers of social studies. This study was conducted in accordance with longitudinal method, which is one of the research designs used in developmental psychology researches. The study was conducted with the…
Sudell, Maria; Tudur Smith, Catrin; Gueyffier, François; Kolamunnage-Dona, Ruwanthi
2018-04-15
Joint modelling of longitudinal and time-to-event data is often preferred over separate longitudinal or time-to-event analyses as it can account for study dropout, error in longitudinally measured covariates, and correlation between longitudinal and time-to-event outcomes. The joint modelling literature focuses mainly on the analysis of single studies with no methods currently available for the meta-analysis of joint model estimates from multiple studies. We propose a 2-stage method for meta-analysis of joint model estimates. These methods are applied to the INDANA dataset to combine joint model estimates of systolic blood pressure with time to death, time to myocardial infarction, and time to stroke. Results are compared to meta-analyses of separate longitudinal or time-to-event models. A simulation study is conducted to contrast separate versus joint analyses over a range of scenarios. Using the real dataset, similar results were obtained by using the separate and joint analyses. However, the simulation study indicated a benefit of use of joint rather than separate methods in a meta-analytic setting where association exists between the longitudinal and time-to-event outcomes. Where evidence of association between longitudinal and time-to-event outcomes exists, results from joint models over standalone analyses should be pooled in 2-stage meta-analyses. © 2017 The Authors. Statistics in Medicine Published by John Wiley & Sons Ltd.
Sandler, I N; Tein, J Y; West, S G
1994-12-01
The authors conducted a cross-sectional and prospective longitudinal study of stress, coping, and psychological symptoms in children of divorce. The sample consisted of 258 children (mean age = 10.1; SD = 1.2), of whom 196 were successfully followed 5.5 months later. A 4-dimensional model of coping was found using confirmatory factor analysis, with the factors being active coping, avoidance, distraction, and support. In the cross-sectional model avoidance coping partially mediated the relations between negative events and symptoms while active coping moderated the relations between negative events and conduct problems. In the longitudinal model significant negative paths were found from active coping and distraction Time 1 to internalizing symptoms Time 2, while Time 1 support coping had a positive path coefficient to Time 2 depression. Positive paths were found between negative events at Time 1 and anxiety at Time 2, and between all symptoms at Time 1 and negative events at Time 2.
Longitudinal conductivity in strong magnetic field in perturbative QCD: Complete leading order
NASA Astrophysics Data System (ADS)
Hattori, Koichi; Li, Shiyong; Satow, Daisuke; Yee, Ho-Ung
2017-04-01
We compute the longitudinal electrical conductivity in the presence of a strong background magnetic field in complete leading order of perturbative QCD, based on the assumed hierarchy of scales αse B ≪(mq2,T2)≪e B . We formulate an effective kinetic theory of lowest Landau level quarks with the leading order QCD collision term arising from 1-to-2 processes that become possible due to 1 +1 dimensional Landau level kinematics. In the small mq/T ≪1 regime, the longitudinal conductivity behaves as σz z˜e2(e B )T /(αsmq2log (T /mq)) , where the quark mass dependence can be understood from the chiral anomaly with the axial charge relaxation provided by a finite quark mass mq. We also present parametric estimates for the longitudinal and transverse "color conductivities" in the presence of the strong magnetic field, by computing dominant damping rates for quarks and gluons that are responsible for color charge transportation. We observe that the longitudinal color conductivity is enhanced by the strong magnetic field, which implies that the sphaleron transition rate in perturbative QCD is suppressed by the strong magnetic field due to the enhanced Lenz's law in color field dynamics.
No Exit: Predicting Student Persistence. AIR 1990 Annual Forum Paper.
ERIC Educational Resources Information Center
Beil, Cheryl; Shope, Janet H.
A longitudinal study was conducted to determine the factors influencing college student persistence in remaining in school. Persistence was examined at two points: after the first year and 4 years after enrollment. The study was conducted at an urban university using the American College Testing's Entering Student Survey and Student Opinion…
ERIC Educational Resources Information Center
Anderson, Elena M.; Wolinsky, Fredric D.; Miller, J. Phillip; Wilson, Margaret-Mary G.; Malmstrom, Theodore K.; Miller, Douglas K.
2006-01-01
Purpose: The purpose of this study is to cross-sectionally and longitudinally identify risk factors for falls, fear of falling, and falls efficacy in late-middle-aged African Americans. Design and Methods: We performed in-home assessments on a probability sample of 998 African Americans and conducted two annual follow-up interviews. Multiple…
ERIC Educational Resources Information Center
Zhang, Peter H.
2013-01-01
This research attempted to reveal the existence of digital divides, their relationships to users' socio-demographics, and the Internet adoption and usage patterns. It was a longitudinal investigation targeted to the adults eighteen years or older in the household setting from the nation-wide surveys conducted in the United States between 2000…
ERIC Educational Resources Information Center
National Centre for Vocational Education Research (NCVER), 2011
2011-01-01
In November and early December 2010, the National Centre for Vocational Education Research (NCVER) conducted consultations to identify research topics using the Longitudinal Surveys of Australian Youth (LSAY). LSAY tracks young people from the age of 15 to 25 as they move from school into further study, work and other destinations. It uses large,…
ERIC Educational Resources Information Center
Jones, Deborah J.; Foster, Sarah E.; Olson, Ardis L.; Forehand, Rex L.; Gaffney, Cecelia A.; Zens, Michael S.; Bau, J. J.
2007-01-01
This study examined the association between ecological context (extrafamilial, familial, child factors) at baseline and longitudinal retention of families in the 36-month assessment of an adolescent alcohol and tobacco use prevention program that was conducted within a pediatric primary care setting. A total of 1,780 families were enrolled at…
Ybema, Jan F; van der Meer, Laudry; Leijten, Fenna R M
2016-10-01
The aim of this study was to assess whether organizational justice lowers productivity loss and sickness absence, and whether there are reverse effects of productivity loss and sickness absence on organizational justice. A longitudinal study with 2 years of follow-up was conducted among employed persons aged 45-64 years from the Study on Transitions in Employment, Ability and Motivation (STREAM). Participants (N = 7011) yearly filled out an online questionnaire. Structural equation modeling in LISREL was conducted to assess the longitudinal relationships between distributive justice of salary, distributive justice of appreciation, procedural justice, productivity loss, and sickness absence. Both distributive justice of appreciation and procedural justice contributed to lower productivity loss and lower sickness absence at 1-year follow-up. Productivity loss increased perceptions of distributive justice of appreciation at 1-year follow-up, whereas sickness absence lowered both perceptions of distributive justice of appreciation and procedural justice at follow-up. Improving organizational justice lowers the risk of productivity loss and sickness absence and may be a useful tool to improve the productivity of organizations.
Modeling Longitudinal Data Containing Non-Normal Within Subject Errors
NASA Technical Reports Server (NTRS)
Feiveson, Alan; Glenn, Nancy L.
2013-01-01
The mission of the National Aeronautics and Space Administration’s (NASA) human research program is to advance safe human spaceflight. This involves conducting experiments, collecting data, and analyzing data. The data are longitudinal and result from a relatively few number of subjects; typically 10 – 20. A longitudinal study refers to an investigation where participant outcomes and possibly treatments are collected at multiple follow-up times. Standard statistical designs such as mean regression with random effects and mixed–effects regression are inadequate for such data because the population is typically not approximately normally distributed. Hence, more advanced data analysis methods are necessary. This research focuses on four such methods for longitudinal data analysis: the recently proposed linear quantile mixed models (lqmm) by Geraci and Bottai (2013), quantile regression, multilevel mixed–effects linear regression, and robust regression. This research also provides computational algorithms for longitudinal data that scientists can directly use for human spaceflight and other longitudinal data applications, then presents statistical evidence that verifies which method is best for specific situations. This advances the study of longitudinal data in a broad range of applications including applications in the sciences, technology, engineering and mathematics fields.
Cosco, T D; Kaushal, A; Hardy, R; Richards, M; Kuh, D; Stafford, M
2017-01-01
Over the life course, we are invariably faced with some form of adversity. The process of positively adapting to adverse events is known as 'resilience'. Despite the acknowledgement of 2 common components of resilience, that is, adversity and positive adaptation, no consensus operational definition has been agreed. Resilience operationalisations have been reviewed in a cross-sectional context; however, a review of longitudinal methods of operationalising resilience has not been conducted. The present study conducts a systematic review across Scopus and Web of Science capturing studies of ageing that posited operational definitions of resilience in longitudinal studies of ageing. Thirty-six studies met inclusion criteria. Non-acute events, for example, cancer, were the most common form of adversity identified and psychological components, for example, the absence of depression, the most common forms of positive adaptation. Of the included studies, 4 used psychometrically driven methods, that is, repeated administration of established resilience metrics, 9 used definition-driven methods, that is, a priori establishment of resilience components and criteria, and 23 used data-driven methods, that is, techniques that identify resilient individuals using latent variable models. Acknowledging the strengths and limitations of each operationalisation is integral to the appropriate application of these methods to life course and longitudinal resilience research. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.
Linear magnetoconductivity in an intrinsic topological Weyl semimetal
NASA Astrophysics Data System (ADS)
Zhang, Song-Bo; Lu, Hai-Zhou; Shen, Shun-Qing
2016-05-01
Searching for the signature of the violation of chiral charge conservation in solids has inspired a growing passion for the magneto-transport in topological semimetals. One of the open questions is how the conductivity depends on magnetic fields in a semimetal phase when the Fermi energy crosses the Weyl nodes. Here, we study both the longitudinal and transverse magnetoconductivity of a topological Weyl semimetal near the Weyl nodes with the help of a two-node model that includes all the topological semimetal properties. In the semimetal phase, the Fermi energy crosses only the 0th Landau bands in magnetic fields. For a finite potential range of impurities, it is found that both the longitudinal and transverse magnetoconductivity are positive and linear at the Weyl nodes, leading to an anisotropic and negative magnetoresistivity. The longitudinal magnetoconductivity depends on the potential range of impurities. The longitudinal conductivity remains finite at zero field, even though the density of states vanishes at the Weyl nodes. This work establishes a relation between the linear magnetoconductivity and the intrinsic topological Weyl semimetal phase.
NASA Technical Reports Server (NTRS)
Blair, A. B., Jr.
1990-01-01
Wind tunnel tests were conducted on monoplanar circular missile configurations with low-profile quadriform tail fins to provide an aerodynamic data base to study and evaluate air-launched missile candidates for efficient conformal carriage on supersonic-cruise-type aircraft. The tests were conducted at Mach numbers from 1.70 to 2.86 for a constant Reynolds number per foot of 2,000,000. Selected test results are presented to show the effects of tail-fin dihedral angle, wing longitudinal and vertical location, and nose-body strakes on the static longitudinal and lateral-directional aerodynamic stability and control characteristics.
2017-10-01
11 1. Introduction: Background and Purpose: One of the earliest and longest running studies of Gulf War veteran’s (GWV) health was conducted...the 1990s. These findings included early documentation of the most common health symptoms, cognitive decrements in environmentally exposed GWV, and...has been followed with longitudinal health surveys, and we are completing a resurvey and biomarker study in which 50% of prior surveyed individuals
NASA Astrophysics Data System (ADS)
Sudicky, E. A.; Illman, W. A.; Goltz, I. K.; Adams, J. J.; McLaren, R. G.
2010-01-01
The spatial variability of hydraulic conductivity in a shallow unconfined aquifer located at North Bay, Ontario, composed of glacial-lacustrine and glacial-fluvial sands, is examined in exceptional detail and characterized geostatistically. A total of 1878 permeameter measurements were performed at 0.05 m vertical intervals along cores taken from 20 boreholes along two intersecting transect lines. Simultaneous three-dimensional (3-D) fitting of Ln(K) variogram data to an exponential model yielded geostatistical parameters for the estimation of bulk hydraulic conductivity and solute dispersion parameters. The analysis revealed a Ln(K) variance equal to about 2.0 and 3-D anisotropy of the correlation structure of the heterogeneity (λ1, λ2, and λ3 equal to 17.19, 7.39, and 1.0 m, respectively). Effective values of the hydraulic conductivity tensor and the value of the longitudinal macrodispersivity were calculated using the theoretical expressions of Gelhar and Axness (1983). The magnitude of the longitudinal macrodispersivity is reasonably consistent with the observed degree of longitudinal dispersion of the landfill plume along the principal path of migration. Variably saturated 3-D flow modeling using the statistically derived effective hydraulic conductivity tensor allowed a reasonably close prediction of the measured water table and the observed heads at various depths in an array of piezometers. Concomitant transport modeling using the calculated longitudinal macrodispersivity reasonably predicted the extent and migration rates of the observed contaminant plume that was monitored using a network of multilevel samplers over a period of about 5 years. It was further demonstrated that the length of the plume is relatively insensitive to the value of the longitudinal macrodispersivity under the conditions of a steady flow in 3-D and constant source strength. This study demonstrates that the use of statistically derived parameters based on stochastic theories results in reliable large-scale 3-D flow and transport models for complex hydrogeological systems. This is in agreement with the conclusions reached by Sudicky (1986) at the site of an elaborate tracer test conducted in the aquifer at the Canadian Forces Base Borden.
Murray, Matthew M.; Wilfong, Dennis H.; Lomax, Ralph E.
1998-01-01
An electrical cable for connecting transient voltage surge suppressers to ectrical power panels. A strip of electrically conductive foil defines a longitudinal axis, with a length of an electrical conductor electrically attached to the metallic foil along the longitudinal axis. The strip of electrically conductive foil and the length of an electrical conductor are covered by an insulating material. For impedance matching purposes, triangular sections can be removed from the ends of the electrically conductive foil at the time of installation.
Murray, M.M.; Wilfong, D.H.; Lomax, R.E.
1998-12-08
An electrical cable for connecting transient voltage surge suppressors to electrical power panels. A strip of electrically conductive foil defines a longitudinal axis, with a length of an electrical conductor electrically attached to the metallic foil along the longitudinal axis. The strip of electrically conductive foil and the length of an electrical conductor are covered by an insulating material. For impedance matching purposes, triangular sections can be removed from the ends of the electrically conductive foil at the time of installation. 6 figs.
Rolled-up transmission line structure for a radiofrequency integrated circuit (RFIC)
Li, Xiuling; Huang, Wen
2015-04-28
A rolled-up transmission line structure for a radiofrequency integrated circuit (RFIC) comprises a multilayer sheet in a rolled configuration comprising multiple turns about a longitudinal axis, where the multilayer sheet comprises a conductive pattern layer on a strain-relieved layer. The conductive pattern layer comprises a first conductive film and a second conductive film separated from the first conductive film in a rolling direction. In the rolled configuration, the first conductive film surrounds the longitudinal axis, and the second conductive film surrounds the first conductive film. The first conductive film serves as a signal line and the second conductive film serves as a conductive shield for the rolled-up transmission line structure.
Wang, Ming-Te; Kenny, Sarah
2014-01-01
This study used cross-lagged modeling to examine reciprocal relations between maternal and paternal harsh verbal discipline and adolescents' conduct problems and depressive symptoms. Data were from a sample of 976 two-parent families and their children (51% males; 54% European American, 40% African American). Mothers' and fathers' harsh verbal discipline at age 13 predicted an increase in adolescent conduct problems and depressive symptoms between ages 13 and 14. A child effect was also present, with adolescent misconduct at age 13 predicting increases in mothers' and fathers' harsh verbal discipline between ages 13 and 14. Furthermore, maternal and paternal warmth did not moderate the longitudinal associations between mothers' and fathers' use of harsh verbal discipline and adolescent conduct problems and depressive symptoms. © 2013 The Authors. Child Development © 2013 Society for Research in Child Development, Inc.
Solomon, Patricia; O'Brien, Kelly K; Nixon, Stephanie; Letts, Lori; Baxter, Larry; Gervais, Nicole
2018-04-20
To examine the episodic disability experiences of older women living with HIV over time. Qualitative longitudinal study, conducting semistructured in-depth interviews on four occasions over a 20-month time frame. Inductive thematic analyses were conducted cross-sectionally and longitudinally. Participants were recruited from HIV community organisations in Canada. 10 women aged 50 years or older living with HIV for more than 6 years. Two major themes related to the episodic nature of the women's disability. Women were living with multiple and complex sources of uncertainty over time including: unpredictable health challenges, worrying about cognition, unreliable weather, fearing stigma and the effects of disclosure, maintaining housing and adequate finances, and fulfilling gendered and family roles. Women describe strategies to deal with uncertainty over time including withdrawing and limiting activities and participation and engaging in meaningful activities. This longitudinal study highlighted the disabling effects of HIV over time in which unpredictable fluctuations in illness and health resulted in uncertainty and worrying about the future. Environmental factors, such as stigma and weather, may put older women living with HIV at a greater risk for social isolation. Strategies to promote dealing with uncertainty and building resilience are warranted. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
ERIC Educational Resources Information Center
Iyer, Padmini; Moore, Rhiannon
2017-01-01
This paper examines the way in which learning quality has been conceptualised and measured in school effectiveness surveys conducted by Young Lives, a longitudinal study of child poverty. Primary school surveys were conducted in Vietnam in 2010-11 and Ethiopia in 2012-13, and surveys at upper-primary and secondary level were conducted in Ethiopia,…
Social Cognition and Conduct Problems: A Developmental Approach
ERIC Educational Resources Information Center
Oliver, Bonamy R.; Barker, Edward D.; Mandy, William P. L.; Skuse, David H.; Maughan, Barbara
2011-01-01
Objective: To estimate associations between trajectories of conduct problems and social-cognitive competences through childhood into early adolescence. Method: A prospective population-based cohort, the Avon Longitudinal Study of Parents and Children (ALSPAC) recruited in the prenatal period (13,988 children alive at 12 months) formed the basis…
LADES: a software for constructing and analyzing longitudinal designs in biomedical research.
Vázquez-Alcocer, Alan; Garzón-Cortes, Daniel Ladislao; Sánchez-Casas, Rosa María
2014-01-01
One of the most important steps in biomedical longitudinal studies is choosing a good experimental design that can provide high accuracy in the analysis of results with a minimum sample size. Several methods for constructing efficient longitudinal designs have been developed based on power analysis and the statistical model used for analyzing the final results. However, development of this technology is not available to practitioners through user-friendly software. In this paper we introduce LADES (Longitudinal Analysis and Design of Experiments Software) as an alternative and easy-to-use tool for conducting longitudinal analysis and constructing efficient longitudinal designs. LADES incorporates methods for creating cost-efficient longitudinal designs, unequal longitudinal designs, and simple longitudinal designs. In addition, LADES includes different methods for analyzing longitudinal data such as linear mixed models, generalized estimating equations, among others. A study of European eels is reanalyzed in order to show LADES capabilities. Three treatments contained in three aquariums with five eels each were analyzed. Data were collected from 0 up to the 12th week post treatment for all the eels (complete design). The response under evaluation is sperm volume. A linear mixed model was fitted to the results using LADES. The complete design had a power of 88.7% using 15 eels. With LADES we propose the use of an unequal design with only 14 eels and 89.5% efficiency. LADES was developed as a powerful and simple tool to promote the use of statistical methods for analyzing and creating longitudinal experiments in biomedical research.
Longitudinal Variation of the Lunar Tide in the Equatorial Electrojet
NASA Astrophysics Data System (ADS)
Yamazaki, Yosuke; Stolle, Claudia; Matzka, Jürgen; Siddiqui, Tarique A.; Lühr, Hermann; Alken, Patrick
2017-12-01
The atmospheric lunar tide is one known source of ionospheric variability. The subject received renewed attention as recent studies found a link between stratospheric sudden warmings and amplified lunar tidal perturbations in the equatorial ionosphere. There is increasing evidence from ground observations that the lunar tidal influence on the ionosphere depends on longitude. We use magnetic field measurements from the CHAMP satellite during July 2000 to September 2010 and from the two Swarm satellites during November 2013 to February 2017 to determine, for the first time, the complete seasonal-longitudinal climatology of the semidiurnal lunar tidal variation in the equatorial electrojet intensity. Significant longitudinal variability is found in the amplitude of the lunar tidal variation, while the longitudinal variability in the phase is small. The amplitude peaks in the Peruvian sector (˜285°E) during the Northern Hemisphere winter and equinoxes, and in the Brazilian sector (˜325°E) during the Northern Hemisphere summer. There are also local amplitude maxima at ˜55°E and ˜120°E. The longitudinal variation is partly due to the modulation of ionospheric conductivities by the inhomogeneous geomagnetic field. Another possible cause of the longitudinal variability is neutral wind forcing by nonmigrating lunar tides. A tidal spectrum analysis of the semidiurnal lunar tidal variation in the equatorial electrojet reveals the dominance of the westward propagating mode with zonal wave number 2 (SW2), with secondary contributions by westward propagating modes with zonal wave numbers 3 (SW3) and 4 (SW4). Eastward propagating waves are largely absent from the tidal spectrum. Further study will be required for the relative importance of ionospheric conductivities and nonmigrating lunar tides.
An Examination of the Developmental Propensity Model of Conduct Problems
Rhee, Soo Hyun; Friedman, Naomi P.; Corley, Robin P.; Hewitt, John K.; Hink, Laura K.; Johnson, Daniel P.; Watts, Ashley K. Smith; Young, Susan E.; Robinson, JoAnn; Waldman, Irwin D.; Zahn-Waxler, Carolyn
2015-01-01
The present study tested specific hypotheses advanced by the developmental propensity model of the etiology of conduct problems in the Colorado Longitudinal Twin Study, a prospective, longitudinal, genetically informative sample. High negative emotionality, low behavioral inhibition, low concern and high disregard for others, and low cognitive ability assessed during toddlerhood (age 14 to 36 months) were examined as predictors of conduct problems in later childhood and adolescence (age 4 to 17 years). Each hypothesized antisocial propensity dimension predicted conduct problems, but some predictions may be context specific or due to method covariance. The most robust predictors were observed disregard for others (i.e., responding to others’ distress with active, negative responses such as anger and hostility), general cognitive ability, and language ability, which were associated with conduct problems reported by parents, teachers, and adolescents, and change in observed negative emotionality (i.e., frustration tolerance), which was associated with conduct problems reported by teachers and adolescents. Furthermore, associations between the most robust early predictors and later conduct problems were influenced by the shared environment rather than genes. We conclude that shared environmental influences that promote disregard for others and detract from cognitive and language development during toddlerhood also predispose individuals to conduct problems in later childhood and adolescence. The identification of those shared environmental influences common to early antisocial propensity and later conduct problems is an important future direction, and additional developmental behavior genetic studies examining the interaction between children’s characteristics and socializing influences on conduct problems are needed. PMID:26653135
Longitudinal Study of the Market Penetration of Cockpit Weather Information Systems
NASA Technical Reports Server (NTRS)
Stough, Harry Paul, III; Sireli, Yesim; Ozan, Erol; Kauffmann, Paul
2005-01-01
The purpose of the longitudinal research of the market penetration of cockpit weather information systems (CWIS) is to contribute to the body of knowledge on modeling advanced technology feasibility in aviation by tracking and analyzing the market adoption of CWIS over a three year period. This research takes advantage of a previous study, conducted by Dr. Paul Kauffmann in 2000, which demonstrated an integrated and cost effective approach to evaluate advanced technology feasibility, examining the feasibility of CWIS in five market segments: transport, commuter, general aviation, business, and rotorcraft. The longitudinal research consists of two consecutive studies and produced two reports. The first report was submitted in August 2003 and included general market analysis about the CWIS products in the market at the time, identified their characteristics and examined developing market dynamics.
ERIC Educational Resources Information Center
Krettenauer, Tobias; Asendorpf, Jens B.; Nunner-Winkler, Gertrud
2013-01-01
The study investigated long-term relations between moral emotion attributions in childhood and adolescence and antisocial conduct in early adulthood while taking into account potentially confounding personality factors. Specifically, onset of prediction, unique and indirect effects of moral emotion attributions were examined. In a longitudinal…
Confrontation Naming and Reading Abilities at Primary School: A Longitudinal Study
Savelli, Enrico; Termine, Cristiano
2015-01-01
Background. Confrontation naming tasks are useful in the assessment of children with learning and language disorders. Objectives. The aims of this study were (1) providing longitudinal data on confrontation naming; (2) investigating the role of socioeconomic status (SES), intelligence, age, and gender in confrontation naming; (3) identifying relationship between confrontation naming and reading abilities (fluency, accuracy, and comprehension). Method. A five-year longitudinal investigation of confrontation naming (i.e., the Boston Naming Test (BNT)) in a nonclinical sample of Italian primary school children was conducted (n = 126), testing them at the end of each school year, to assess nonverbal intelligence, confrontation naming, and reading abilities. Results. Performance on the BNT emerged as a function of IQ and SES. Significant correlations between confrontation naming and reading abilities, especially comprehension, were found; BNT scores correlated better with reading fluency than with reading accuracy. Conclusions. The longitudinal data obtained in this study are discussed with regard to reading abilities, intelligence, age, gender, and socioeconomic status. PMID:26124541
Lu, Tao; Lu, Minggen; Wang, Min; Zhang, Jun; Dong, Guang-Hui; Xu, Yong
2017-12-18
Longitudinal competing risks data frequently arise in clinical studies. Skewness and missingness are commonly observed for these data in practice. However, most joint models do not account for these data features. In this article, we propose partially linear mixed-effects joint models to analyze skew longitudinal competing risks data with missingness. In particular, to account for skewness, we replace the commonly assumed symmetric distributions by asymmetric distribution for model errors. To deal with missingness, we employ an informative missing data model. The joint models that couple the partially linear mixed-effects model for the longitudinal process, the cause-specific proportional hazard model for competing risks process and missing data process are developed. To estimate the parameters in the joint models, we propose a fully Bayesian approach based on the joint likelihood. To illustrate the proposed model and method, we implement them to an AIDS clinical study. Some interesting findings are reported. We also conduct simulation studies to validate the proposed method.
Yu, Rongqin; Branje, Susan; Meeus, Wim; Koot, Hans M; van Lier, Pol; Fazel, Seena
2018-05-01
Despite evidence of a positive link between depressive symptoms and violent behaviors, the pathways underlying this longitudinal association remain unknown. Depressive symptoms might drive and reinforce victimization which in turn could increase risk of individuals becoming violent towards others. Thus, we tested whether victimization mediated the link between depressive symptoms and violent behaviors using a 6-year longitudinal study of a community sample of adolescents. The sample included 682 Dutch adolescents (54% boys) from an ongoing longitudinal study RADAR (Research on Adolescent Development and Relationships). From ages 13 to 18 years, depressive symptoms, victimization experiences, and violent behaviors were annually assessed. We conducted longitudinal mediation analyses to test pathways to violence in adolescents with depressive symptoms. Longitudinal analyses revealed that victimization mediated the association between depressive symptoms and violent behaviors from early to late adolescence. As part of this, we found that adolescents' depressive symptoms predicted victimization, and this victimization increased risk of subsequent violent behaviors. In conclusion, links between depressive symptoms and violent behaviors are potentially important to understand adolescent development. Decreasing the occurence of victimization is likely to be an important target for the prevention of violent behaviors in adolescents with depressive symptoms.
Liquid-like thermal conduction in intercalated layered crystalline solids
Li, B.; Wang, H.; Kawakita, Y.; ...
2018-01-15
As a generic property, all substances transfer heat through microscopic collisions of constituent particles. A solid conducts heat through both transverse and longitudinal acoustic phonons, but a liquid employs only longitudinal vibrations. As a result, a solid is usually thermally more conductive than a liquid. In canonical viewpoints, such a difference also serves as the dynamic signature distinguishing a solid from a liquid. Here in this work, we report liquid-like thermal conduction observed in the crystalline AgCrSe 2. The transverse acoustic phonons are completely suppressed by the ultrafast dynamic disorder while the longitudinal acoustic phonons are strongly scattered but survive,more » and are thus responsible for the intrinsically ultralow thermal conductivity. This scenario is applicable to a wide variety of layered compounds with heavy intercalants in the van der Waals gaps, manifesting a broad implication on suppressing thermal conduction. Finally, these microscopic insights might reshape the fundamental understanding on thermal transport properties of matter and open up a general opportunity to optimize performances of thermoelectrics.« less
Liquid-like thermal conduction in intercalated layered crystalline solids
NASA Astrophysics Data System (ADS)
Li, B.; Wang, H.; Kawakita, Y.; Zhang, Q.; Feygenson, M.; Yu, H. L.; Wu, D.; Ohara, K.; Kikuchi, T.; Shibata, K.; Yamada, T.; Ning, X. K.; Chen, Y.; He, J. Q.; Vaknin, D.; Wu, R. Q.; Nakajima, K.; Kanatzidis, M. G.
2018-03-01
As a generic property, all substances transfer heat through microscopic collisions of constituent particles1. A solid conducts heat through both transverse and longitudinal acoustic phonons, but a liquid employs only longitudinal vibrations2,3. As a result, a solid is usually thermally more conductive than a liquid. In canonical viewpoints, such a difference also serves as the dynamic signature distinguishing a solid from a liquid. Here, we report liquid-like thermal conduction observed in the crystalline AgCrSe2. The transverse acoustic phonons are completely suppressed by the ultrafast dynamic disorder while the longitudinal acoustic phonons are strongly scattered but survive, and are thus responsible for the intrinsically ultralow thermal conductivity. This scenario is applicable to a wide variety of layered compounds with heavy intercalants in the van der Waals gaps, manifesting a broad implication on suppressing thermal conduction. These microscopic insights might reshape the fundamental understanding on thermal transport properties of matter and open up a general opportunity to optimize performances of thermoelectrics.
Liquid-like thermal conduction in intercalated layered crystalline solids
DOE Office of Scientific and Technical Information (OSTI.GOV)
Li, B.; Wang, H.; Kawakita, Y.
As a generic property, all substances transfer heat through microscopic collisions of constituent particles. A solid conducts heat through both transverse and longitudinal acoustic phonons, but a liquid employs only longitudinal vibrations. As a result, a solid is usually thermally more conductive than a liquid. In canonical viewpoints, such a difference also serves as the dynamic signature distinguishing a solid from a liquid. Here in this work, we report liquid-like thermal conduction observed in the crystalline AgCrSe 2. The transverse acoustic phonons are completely suppressed by the ultrafast dynamic disorder while the longitudinal acoustic phonons are strongly scattered but survive,more » and are thus responsible for the intrinsically ultralow thermal conductivity. This scenario is applicable to a wide variety of layered compounds with heavy intercalants in the van der Waals gaps, manifesting a broad implication on suppressing thermal conduction. Finally, these microscopic insights might reshape the fundamental understanding on thermal transport properties of matter and open up a general opportunity to optimize performances of thermoelectrics.« less
Conduct, Biological Factors and Adult Delinquency in a Longitudinal Perspective.
ERIC Educational Resources Information Center
Magnusson, David
In the course of a longitudinal research program conducted in Sweden, data were being collected on biological and psychological aspects of individual functioning and on environmental factors for a fairly large representative sample (approximately 1,000) of Swedish males and females between 10 and 27 years of age. Based on data from the…
Ishii, Kaori; Shibata, Ai; Adachi, Minoru; Oka, Koichiro
2016-10-01
Data on the effect of increased or decreased physical activity on children's psychological status are scarce, and effect sizes are small. This study conducted two-year longitudinal research to identify associations between physical activity, sedentary behavior, and psychological well-being in Japanese school children through a mail survey completed by 292 children aged 6-12 years. Data on sociodemographics, physical activity, sedentary behavior on weekdays and the weekend, and psychometrics (self-efficacy, anxiety, and behavioral/emotional problems) were collected using a self-reported questionnaire. A logistic regression analysis was performed, calculating odds ratios for physical activity, psychometrics, and baseline age and physical activity and sedentary behavior changes. For boys, a negative association was found between increased physical activity outside school and maintained or improved self-efficacy as opposed to a positive association in girls. Increased sedentary behavior on weekdays and long periods of sedentary behavior on weekends were associated with maintained or improved behavioral/emotional problems in girls only. This two-year longitudinal study is the first of its kind conducted in Japan. Although effect sizes were small, these results may nevertheless assist in intervention development to promote psychological well-being. © The Author(s) 2016.
Rolled-up inductor structure for a radiofrequency integrated circuit (RFIC)
Li, Xiuling; Huang, Wen; Ferreira, Placid M.; Yu, Xin
2015-12-29
A rolled-up inductor structure for a radiofrequency integrated circuit (RFIC) comprises a multilayer sheet in a rolled configuration comprising multiple turns about a longitudinal axis. The multilayer sheet comprises a conductive pattern layer on a strain-relieved layer, and the conductive pattern layer comprises at least one conductive strip having a length extending in a rolling direction. The at least one conductive strip thereby wraps around the longitudinal axis in the rolled configuration. The conductive pattern layer may also comprise two conductive feed lines connected to the conductive strip for passage of electrical current therethrough. The conductive strip serves as an inductor cell of the rolled-up inductor structure.
NASA Technical Reports Server (NTRS)
Luckring, J. M.
1979-01-01
A systematic wind tunnel study was conducted in the Langley 7 by 10 foot high speed tunnel to help establish a parametric data base of the longitudinal and lateral aerodynamic characteristics for configurations incorporating strake-wing geometries indicative of current and proposed maneuvering aircraft. The configurations employed combinations of strakes with reflexed planforms having exposed spans of 10%, 20%, and 30% of the reference wing span and wings with trapezoidal planforms having leading edge sweep angles of approximately 30, 40, 44, 50, and 60 deg. Tests were conducted at Mach numbers ranging from 0.3 to 0.8 and at angles of attack from approximately -4 to 48 deg at zero sideslip.
Train crashworthiness design for occupant survivability
DOT National Transportation Integrated Search
1995-11-01
Studies were conducted evaluating the effectiveness of alternative strategies for providing crashworthiness of the vehicle structures. Conventional practice results in cars of essentially uniform : longitudinal strength. The crash energy management a...
ERIC Educational Resources Information Center
La Paro, Karen M.; Rimm-Kaufman, Sara E.; Pianta, Robert C.
2006-01-01
This study examines the classroom experiences of 192 children followed longitudinally from kindergarten to 1st grade. Time-sampled observations of children were conducted to compare learning formats, teaching activities, and children's engagement in activities between kindergarten and 1st grade. Classroom observations also were conducted to…
NASA Technical Reports Server (NTRS)
Grantham, W. D.; Deal, P. L.
1974-01-01
A fixed-base simulator study was conducted to determine the minimum acceptable level of longitudinal stability for a representative turbofan STOL (short take-off and landing) transport airplane during the landing approach. Real-time digital simulation techniques were used. The computer was programed with equations of motion for six degrees of freedom, and the aerodynamic inputs were based on measured wind-tunnel data. The primary piloting task was an instrument approach to a breakout at a 60-m (200-ft) ceiling.
Calculation of the conductance of two dimensional narrow wires
NASA Astrophysics Data System (ADS)
Kander, Ilan
1989-05-01
There is an interest in the quantum transport of electrons in systems where the sample dimensions are less than a phase coherence length L(sub phi) which is the distance across which the electrons lose phase memory (typically by inelastic scattering). The two-contact conductance is examined of 2-D systems (strips) as functions of Fermi energy system dimensions as is the amount of disorder at zero temperature. Under these conditions all scattering processes are elastic. The term channel is used in order to describe a quantum state with a given transverse quantum number and the appropriate longitudinal momentum. A channel is considered conducting if its longitudinal momentum is real, and decaying if its longitudinal momentum is imaginary. The calculation of the conductance is done in two ways. Transfer matrix for very long systems and Green's function for relatively short ones. The conductance curve in an ordered system is quantized and in a disordered system it is smeared. Interesting changes in the conductance near the thresholds for changes in the quantized value of the conductance are observed.
Dimensions of integration, continuity and longitudinality in clinical clerkships.
Ellaway, Rachel H; Graves, Lisa; Cummings, Beth-Ann
2016-09-01
Over the past few decades, longitudinal integrated clerkships (LICs) have been proposed to address many perceived short-coming of traditional block clerkships. This growing interest in LICs has raised broader questions regarding the role of integration, continuity and longitudinality in medical education. A study with complementary theoretical and empirical dimensions was conducted to derive a more precise way of defining these three underlying concepts within the design of medical education curricula. The theoretical dimension involved a thematic review of the literature on integration, continuity and longitudinality in medical education. The empirical dimension surveyed all 17 Canadian medical schools on how they have operationalised integration, continuity and longitudinality in their undergraduate programmes. The two dimensions were iteratively synthesised to explore the meaning and expression of integration, continuity and longitudinality in medical education curriculum design. Integration, continuity and longitudinality were expressed in many ways and forms, including: integration of clinical disciplines, combined horizontal integration and vertical integration, and programme-level integration. Types of continuity included: continuity of patients, continuity of teaching, continuity of location and peer continuity. Longitudinality focused on connected or repeating episodes of training or on connecting activities, such as encounter logging across educational episodes. Twelve of the 17 schools were running an LIC of some kind, although only one school had a mandatory LIC experience. An ordinal scale of uses of integration, continuity and longitudinality during clerkships was developed, and new definitions of these concepts in the clerkship context were generated. Different clerkship designs embodied different forms and levels of integration, continuity and longitudinality. A dichotomous view of LICs and rotation-based clerkships was found not to represent current practices in Canada, which instead tended to fall along a continuum of integration, continuity and longitudinality. © 2016 John Wiley & Sons Ltd and The Association for the Study of Medical Education.
Stretchable polymer-based electronic device
Maghribi, Mariam N [Livermore, CA; Krulevitch, Peter A [Pleasanton, CA; Davidson, James Courtney [Livermore, CA; Wilson, Thomas S [Castro Valley, CA; Hamilton, Julie K [Tracy, CA; Benett, William J [Livermore, CA; Tovar, Armando R [San Antonio, TX
2008-02-26
A stretchable electronic circuit or electronic device and a polymer-based process to produce a circuit or electronic device containing a stretchable conducting circuit. The stretchable electronic apparatus has a central longitudinal axis and the apparatus is stretchable in a longitudinal direction generally aligned with the central longitudinal axis. The apparatus comprises a stretchable polymer body and at least one circuit line operatively connected to the stretchable polymer body. The circuit line extends in the longitudinal direction and has a longitudinal component that extends in the longitudinal direction and has an offset component that is at an angle to the longitudinal direction. The longitudinal component and the offset component allow the apparatus to stretch in the longitudinal direction while maintaining the integrity of the circuit line.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ranganayakulu, C.; Seetharamu, K.N.
An analysis of a crossflow plate-fin compact heat exchanger, accounting for the combined effects of two-dimensional longitudinal heat conduction through the exchanger wall and nonuniform inlet fluid flow and temperature distribution is carried out using a finite element method. A mathematical equation is developed to generate different types of fluid flow/temperature maldistribution models considering the possible deviations in fluid flow. Using these models, the exchanger effectiveness and its deterioration due to the combined effects of longitudinal heat conduction, flow nonuniformity and temperature nonuniformity are calculated for various design and operating conditions of the exchanger. It was found that the performancemore » variations are quite significant in some typical applications.« less
Wood, Jeffrey J.; Lynne, Sarah D.; Langer, David A.; Wood, Patricia A.; Clark, Shaunna L.; Eddy, J. Mark; Ialongo, Nicholas
2011-01-01
This study tests a model of reciprocal influences between absenteeism and youth psychopathology using three longitudinal datasets (Ns= 20745, 2311, and 671). Participants in 1st through 12th grades were interviewed annually or bi-annually. Measures of psychopathology include self-, parent-, and teacher-report questionnaires. Structural cross-lagged regression models were tested. In a nationally representative dataset (Add Health), middle school students with relatively greater absenteeism at study year 1 tended towards increased depression and conduct problems in study year 2, over and above the effects of autoregressive associations and demographic covariates. The opposite direction of effects was found for both middle and high school students. Analyses with two regionally representative datasets were also partially supportive. Longitudinal links were more evident in adolescence than in childhood. PMID:22188462
An examination of the developmental propensity model of conduct problems.
Rhee, Soo Hyun; Friedman, Naomi P; Corley, Robin P; Hewitt, John K; Hink, Laura K; Johnson, Daniel P; Smith Watts, Ashley K; Young, Susan E; Robinson, JoAnn; Waldman, Irwin D; Zahn-Waxler, Carolyn
2016-05-01
The present study tested specific hypotheses advanced by the developmental propensity model of the etiology of conduct problems in the Colorado Longitudinal Twin Study, a prospective, longitudinal, genetically informative sample. High negative emotionality, low behavioral inhibition, low concern and high disregard for others, and low cognitive ability assessed during toddlerhood (age 14 to 36 months) were examined as predictors of conduct problems in later childhood and adolescence (age 4 to 17 years). Each hypothesized antisocial propensity dimension predicted conduct problems, but some predictions may be context specific or due to method covariance. The most robust predictors were observed disregard for others (i.e., responding to others' distress with active, negative responses such as anger and hostility), general cognitive ability, and language ability, which were associated with conduct problems reported by parents, teachers, and adolescents, and change in observed negative emotionality (i.e., frustration tolerance), which was associated with conduct problems reported by teachers and adolescents. Furthermore, associations between the most robust early predictors and later conduct problems were influenced by the shared environment rather than genes. We conclude that shared environmental influences that promote disregard for others and detract from cognitive and language development during toddlerhood also predispose individuals to conduct problems in later childhood and adolescence. The identification of those shared environmental influences common to early antisocial propensity and later conduct problems is an important future direction, and additional developmental behavior genetic studies examining the interaction between children's characteristics and socializing influences on conduct problems are needed. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
Graphite fiber/copper matrix composites for space power heat pipe fin applications
NASA Astrophysics Data System (ADS)
McDanels, David L.; Baker, Karl W.; Ellis, David L.
1991-01-01
High specific thermal conductivity (thermal conductivity divided by density) is a major design criterion for minimizing system mass for space power systems. For nuclear source power systems, graphite fiber reinforced copper matrix (Gr/Cu) composites offer good potential as a radiator fin material operating at service temperatures above 500 K. Specific thermal conductivity in the longitudinal direction is better than beryllium and almost twice that of copper. The high specific thermal conductivity of Gr/Cu offers the potential of reducing radiator mass by as much as 30 percent. Gr/Cu composites also offer the designer a range of available properties for various missions and applications. The properties of Gr/Cu are highly anisotropic. Longitudinal elastic modulus is comparable to beryllium and about three times that of copper. Thermal expansion in the longitudinal direction is near zero, while it exceeds that of copper in the transverse direction.
Slotting Fins of Heat Exchangers to Provide Thermal Breaks
NASA Technical Reports Server (NTRS)
Scull, Timothy D.
2003-01-01
Heat exchangers that include slotted fins (in contradistinction to continuous fins) have been invented. The slotting of the fins provides thermal breaks that reduce thermal conduction along flow paths (longitudinal thermal conduction), which reduces heat-transfer efficiency. By increasing the ratio between transverse thermal conduction (the desired heat-transfer conduction) and longitudinal thermal conduction, slotting of the fins can be exploited to (1) increase heat-transfer efficiency (thereby reducing operating cost) for a given heat-exchanger length or to (2) reduce the length (thereby reducing the weight and/or cost) of the heat exchanger needed to obtain a given heat transfer efficiency. By reducing the length of a heat exchanger, one can reduce the pressure drop associated with the flow through it. In a case in which slotting enables the use of fins with thermal conductivity greater than could otherwise be tolerated on the basis of longitudinal thermal conduction, one can exploit the conductivity to make the fins longer (in the transverse direction) than they otherwise could be, thereby making it possible to make a heat exchanger that contains fewer channels and therefore, that weighs less, contains fewer potential leak paths, and can be constructed from fewer parts and, hence, reduced cost.
Skin conductance fear conditioning impairments and aggression: a longitudinal study.
Gao, Yu; Tuvblad, Catherine; Schell, Anne; Baker, Laura; Raine, Adrian
2015-02-01
Autonomic fear conditioning deficits have been linked to child aggression and adult criminal behavior. However, it is unknown if fear conditioning deficits are specific to certain subtypes of aggression, and longitudinal research is rare. In the current study, reactive and proactive aggression were assessed in a sample of males and females when aged 10, 12, 15, and 18 years old. Skin conductance fear conditioning data were collected when they were 18 years old. Individuals who were persistently high on proactive aggression measures had significantly poorer conditioned responses at 18 years old when compared to others. This association was not found for reactive aggression. Consistent with prior literature, findings suggest that persistent antisocial individuals have unique neurobiological characteristics and that poor autonomic fear conditioning is associated with the presence of increased instrumental aggressive behavior. © 2014 Society for Psychophysiological Research.
Gee, Gilbert C.; de Castro, A.B.; Wang, May C.; Crespi, Catherine M.; Morey, Brittany N.; Fujishiro, Kaori
2015-01-01
Most studies of immigrant health are cross-sectional and fail to collect information prior to migration, leading to potential bias and confounding. The present pilot study examines the feasibility of studying migrants prospectively, with baseline data collected before migration. The study followed two cohorts of Filipinos for one year, a migrant cohort (n=27) that emigrated to the U.S. and a second non-migrant cohort (n=26) in the Philippines. The one-year retention rate was 96% The migrant cohort arrived in the U.S. within 2 months of their baseline assessment. Migrants and non-migrants did not differ with regard to body mass index, waist circumference or waist to hip ratio at baseline or at follow-up. It is feasible to conduct a transnational, longitudinal study of two cohorts of Filipinos. This design provides important pre-migration information, is analogous to a natural experiment, can be upscaled, and allows for a rigorous examination of immigrant health. PMID:25913346
Longitudinal Analysis of Academic Burnout in Korean Middle School Students.
Kim, Boyoung; Lee, Minyoung; Kim, Keunhwa; Choi, Hyunju; Lee, Sang Min
2015-10-01
The purpose of the study was to investigate the longitudinal relationships between the initial values and slopes of three dimensions of burnout syndrome (i.e. emotional exhaustion, cynicism and academic inefficacy). The study utilized four-wave longitudinal data from a total of 367 (81.6% response rate) middle school students in South Korea. Comprising a 6-month interval survey, the first survey was conducted in June 2010, the second in December 2010, the third in June 2011 and the fourth in December 2011. All participants were 13-year-olds at the first and second surveys, and 14-year-olds at the third and fourth surveys. The Maslach Burnout Inventory-Student Survey was used for each survey to assess the level of academic burnout. The longitudinal data were analysed using latent growth modelling. The results of the study indicated that high initial values (intercept) for emotional exhaustion were associated with a higher rate of increase (slope) in cynicism and academic inefficacy. On the other hand, high initial values for cynicism and academic inefficacy were associated with a lower rate of increase in the other dimensions. This longitudinal study should promote understanding of burned-out students and contribute to the literature by informing the design of prevention programmes for academic burnout. Copyright © 2014 John Wiley & Sons, Ltd.
Adatoms in graphene nanoribbons: spintronic properties and the quantum spin Hall phase
NASA Astrophysics Data System (ADS)
Ganguly, Sudin; Basu, Saurabh
2017-11-01
We study the charge and spin transport in a two terminal graphene nanoribbon (GNR) decorated with random distribution of Gold (Au) adatoms using a Kane-Mele model. The presence of the quantum spin Hall (QSH) phase is found to crucially depend on the strength of the intrinsic spin-orbit term, while the plateau in the longitudinal conductance at a 2e^2/h value is not the smoking gun for the QSH phase. Thus the Au adatoms which manage to induce only a small intrinsic spin-orbit coupling cannot guarantee a QSH phase, albeit yielding a 2e^2/h plateau in the longitudinal conductance around the zero of the Fermi energy. If other adatoms can induce larger spin-orbit strengths (we call them hypothetical adatoms), they would ensure both the plateau and the QSH phase as is evident from the presence of the conducting edge states. Motivated by these results, the spintronic applications are explored via computing the spin polarized conductance for both Au and hypothetical adatoms. The y-component of the spin polarized conductance renders the dominant contribution owing to the finite width of the GNR in the y-direction and is found to possess strikingly similar features with that of the longitudinal conductance. The other two components, namely x and z are small but finite and hence have relevance in spintronic applications. Moreover, via computing the local current distribution, we show the clear emergence of edge states in the case of hypothetical adatoms, which are conspicuously absent for Au decorated GNRs.
Anomalous thermal conductivity of monolayer boron nitride
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tabarraei, Alireza, E-mail: atabarra@uncc.edu; Wang, Xiaonan
In this paper, we use nonequilibrium molecular dynamics modeling to investigate the thermal properties of monolayer hexagonal boron nitride nanoribbons under uniaxial strain along their longitudinal axis. Our simulations predict that hexagonal boron nitride shows an anomalous thermal response to the applied uniaxial strain. Contrary to three dimensional materials, under uniaxial stretching, the thermal conductivity of boron nitride nanoribbons first increases rather than decreasing until it reaches its peak value and then starts decreasing. Under compressive strain, the thermal conductivity of monolayer boron nitride ribbons monolithically reduces rather than increasing. We use phonon spectrum and dispersion curves to investigate themore » mechanism responsible for the unexpected behavior. Our molecular dynamics modeling and density functional theory results show that application of longitudinal tensile strain leads to the reduction of the group velocities of longitudinal and transverse acoustic modes. Such a phonon softening mechanism acts to reduce the thermal conductivity of the nanoribbons. On the other hand, a significant increase in the group velocity (stiffening) of the flexural acoustic modes is observed, which counteracts the phonon softening effects of the longitudinal and transverse modes. The total thermal conductivity of the ribbons is a result of competition between these two mechanisms. At low tensile strain, the stiffening mechanism overcomes the softening mechanism which leads to an increase in the thermal conductivity. At higher tensile strain, the softening mechanism supersedes the stiffening and the thermal conductivity slightly reduces. Our simulations show that the decrease in the thermal conductivity under compressive strain is attributed to the formation of buckling defects which reduces the phonon mean free path.« less
Robillard, Rébecca; Hermens, Daniel F; Lee, Rico S C; Jones, Andrew; Carpenter, Joanne S; White, Django; Naismith, Sharon L; Southan, James; Whitwell, Bradley; Scott, Elizabeth M; Hickie, Ian B
2016-10-01
Mood disorders are characterized by disabling symptoms and cognitive difficulties which may vary in intensity throughout the course of the illness. Sleep-wake cycles and circadian rhythms influence emotional regulation and cognitive functions. However, the relationships between the sleep-wake disturbances experienced commonly by people with mood disorders and the longitudinal changes in their clinical and cognitive profile are not well characterized. This study investigated associations between initial sleep-wake patterns and longitudinal changes in mood symptoms and cognitive functions in 50 young people (aged 13-33 years) with depression or bipolar disorder. Data were based on actigraphy monitoring conducted over approximately 2 weeks and clinical and neuropsychological assessment. As part of a longitudinal cohort study, these assessments were repeated after a mean follow-up interval of 18.9 months. No significant differences in longitudinal clinical changes were found between the participants with depression and those with bipolar disorder. Lower sleep efficiency was predictive of longitudinal worsening in manic symptoms (P = 0.007). Shorter total sleep time (P = 0.043) and poorer circadian rhythmicity (P = 0.045) were predictive of worsening in verbal memory. These findings suggest that some sleep-wake and circadian disturbances in young people with mood disorders may be associated with less favourable longitudinal outcomes, notably for subsequent manic symptoms and memory difficulties. © 2016 European Sleep Research Society.
Leslie, Eric; Bhargava, Valmik; Mittal, Ravinder K
2012-03-01
A subthreshold pharyngeal stimulus induces lower esophageal sphincter (LES) relaxation and inhibits progression of ongoing peristaltic contraction in the esophagus. Recent studies show that longitudinal muscle contraction of the esophagus may play a role in LES relaxation. Our goal was to determine whether a subthreshold pharyngeal stimulus induces contraction of the longitudinal muscle of the esophagus and to determine the nature of this contraction. Studies were conducted in 16 healthy subjects. High resolution manometry (HRM) recorded pressures, and high frequency intraluminal ultrasound (HFIUS) images recorded longitudinal muscle contraction at various locations in the esophagus. Subthreshold pharyngeal stimulation was induced by injection of minute amounts of water in the pharynx. A subthreshold pharyngeal stimulus induced strong contraction and caudal descent of the upper esophageal sphincter (UES) along with relaxation of the LES. HFIUS identified longitudinal muscle contraction of the proximal (3-5 cm below the UES) but not the distal esophagus. Pharyngeal stimulus, following a dry swallow, blocked the progression of dry swallow-induced peristalsis; this was also associated with UES contraction and descent along with the contraction of longitudinal muscle of the proximal esophagus. We identify a unique pattern of longitudinal muscle contraction of the proximal esophagus in response to subthreshold pharyngeal stimulus, which we propose may be responsible for relaxation of the distal esophagus and LES through the stretch sensitive activation of myenteric inhibitory motor neurons.
Son, Heesook; Friedmann, Erika; Thomas, Sue A
2012-01-01
Longitudinal studies are used in nursing research to examine changes over time in health indicators. Traditional approaches to longitudinal analysis of means, such as analysis of variance with repeated measures, are limited to analyzing complete cases. This limitation can lead to biased results due to withdrawal or data omission bias or to imputation of missing data, which can lead to bias toward the null if data are not missing completely at random. Pattern mixture models are useful to evaluate the informativeness of missing data and to adjust linear mixed model (LMM) analyses if missing data are informative. The aim of this study was to provide an example of statistical procedures for applying a pattern mixture model to evaluate the informativeness of missing data and conduct analyses of data with informative missingness in longitudinal studies using SPSS. The data set from the Patients' and Families' Psychological Response to Home Automated External Defibrillator Trial was used as an example to examine informativeness of missing data with pattern mixture models and to use a missing data pattern in analysis of longitudinal data. Prevention of withdrawal bias, omitted data bias, and bias toward the null in longitudinal LMMs requires the assessment of the informativeness of the occurrence of missing data. Missing data patterns can be incorporated as fixed effects into LMMs to evaluate the contribution of the presence of informative missingness to and control for the effects of missingness on outcomes. Pattern mixture models are a useful method to address the presence and effect of informative missingness in longitudinal studies.
A generalization of the Drude-Smith formula for magneto-optical conductivities in Faraday geometry
DOE Office of Scientific and Technical Information (OSTI.GOV)
Han, F. W.; University of Science and Technology of China, Hefei 230026; Xu, W., E-mail: wenxu-issp@aliyun.com
2016-06-28
In this study, we generalize the impulse response approach and Poisson statistics proposed by Smith [Phys. Rev. B 64, 155106 (2001)] to evaluate the longitudinal and transverse magneto-optical conductivities in an electron gas system in Faraday geometry. Comparing with the standard Drude model, the coefficients a{sub n} are introduced in the Drude-Smith formula to describe the backscattering or localization effect for the nth electronic scattering event. Such a formula can also be applied to study the elements of the dielectric function matrix in the presence of magnetic and radiation fields in electron gas systems. This theoretical work is primely motivatedmore » by recent experimental activities in measuring the real and imaginary parts of longitudinal and transverse magneto-optical conductivities in condensed matter materials and electronic devices using terahertz time-domain spectroscopy. We believe that the results obtained from this study can provide an appropriate theoretical tool in reproducing the experimental findings and in fitting with experimental data to determine the important sample and material parameters.« less
The Development of Skin Conductance Fear Conditioning in Children from Ages 3 to 8 Years
ERIC Educational Resources Information Center
Gao, Yu; Raine, Adrian; Venables, Peter H.; Dawson, Michael E.; Mednick, Sarnoff A.
2010-01-01
Although fear conditioning is an important psychological construct implicated in behavioral and emotional problems, little is known about how it develops in early childhood. Using a differential, partial reinforcement conditioning paradigm, this longitudinal study assessed skin conductance conditioned responses in 200 children at ages 3, 4, 5, 6,…
Conduct Disorder and Initiation of Substance Use: A Prospective Longitudinal Study
ERIC Educational Resources Information Center
Hopfer, Christian; Salomonsen-Sautel, Stacy; Mikulich-Gilbertson, Susan; Min, Sung-Joon; McQueen, Matt; Crowley, Thomas; Young, Susan; Corley, Robin; Sakai, Joseph; Thurstone, Christian; Hoffenberg, Analice; Hartman, Christie; Hewitt, John
2013-01-01
Objective: To examine the influence of conduct disorder (CD) on substance use initiation. Method: Community adolescents without CD (n = 1,165, mean baseline age = 14.6 years), with CD (n = 194, mean baseline age = 15.3 years), and youth with CD recruited from treatment (n = 268, mean baseline age = 15.7 years) were prospectively followed and…
ERIC Educational Resources Information Center
Monuteaux, Michael C.; Blacker, Deborah; Biederman, Joseph; Fitzmaurice, Garrett; Buka, Stephen L.
2006-01-01
Background: Empirical evidence demonstrates that conduct disorder (CD) symptoms tend to cluster into covert and overt domains. We hypothesized that overt and covert CD symptoms may be distinct constructs with distinct risk factors. An important risk factor for CD is maternal smoking during pregnancy. We further investigated this association,…
Thermal Conductivity Measurement of Anisotropic Biological Tissue In Vitro
NASA Astrophysics Data System (ADS)
Yue, Kai; Cheng, Liang; Yang, Lina; Jin, Bitao; Zhang, Xinxin
2017-06-01
The accurate determination of the thermal conductivity of biological tissues has implications on the success of cryosurgical/hyperthermia treatments. In light of the evident anisotropy in some biological tissues, a new modified stepwise transient method was proposed to simultaneously measure the transverse and longitudinal thermal conductivities of anisotropic biological tissues. The physical and mathematical models were established, and the analytical solution was derived. Sensitivity analysis and experimental simulation were performed to determine the feasibility and measurement accuracy of simultaneously measuring the transverse and longitudinal thermal conductivities. The experimental system was set up, and its measurement accuracy was verified by measuring the thermal conductivity of a reference standard material. The thermal conductivities of the pork tenderloin and bovine muscles were measured using the traditional 1D and proposed methods, respectively, at different temperatures. Results indicate that the thermal conductivities of the bovine muscle are lower than those of the pork tenderloin muscle, whereas the bovine muscle was determined to exhibit stronger anisotropy than the pork tenderloin muscle. Moreover, the longitudinal thermal conductivity is larger than the transverse thermal conductivity for the two tissues and all thermal conductivities increase with the increase in temperature. Compared with the traditional 1D method, results obtained by the proposed method are slightly higher although the relative deviation is below 5 %.
Fosco, Gregory M; Feinberg, Mark E
2015-02-01
This study examined the longitudinal implications of adolescents' exposure to interparental conflict for their developmental success. In the proposed developmental cascade model, adolescents' perceptions of parental conflict as threatening is a risk factor for diminished self-efficacy, which would account for diminished adjustment. This study presents longitudinal data for 768 sixth-grade students and their families over four time points, ending in eighth grade. Analyses were conducted in three steps. First, replication of longitudinal support for threat as a mediator of the link between interparental conflict and emotional distress was found; however, findings did not support threat as a mediator of behavior problems or subjective well-being. Second, threat was found to mediate the longitudinal association between interparental conflict and self-efficacy. Third, a developmental cascade model supported a risk process in which interparental conflict was related to adolescents' threat appraisals, which undermined self-efficacy beliefs, and was then linked with emotional distress, behavior problems, and subjective well-being.
Valkenburg, Patti M; Koutamanis, Maria; Vossen, Helen G M
2017-11-01
The first aim of this study was to investigate the concurrent and longitudinal relationships between adolescents' use of social network sites (SNSs) and their social self-esteem. The second aim was to investigate whether the valence of the feedback that adolescents receive on SNSs can explain these relationships. We conducted a three-wave panel study among 852 pre- and early adolescents (10-15 years old). In line with earlier research, we found significant concurrent correlations between adolescents' SNS use and their social self-esteem in all three data waves. The longitudinal results only partly confirmed these concurrent findings: Adolescents' initial SNS use did not significantly influence their social self-esteem in subsequent years. In contrast, their initial social self-esteem consistently influenced their SNS use in subsequent years. The valence of online feedback from close friends and acquaintances explained the concurrent relationship between SNS use and social self-esteem, but not the longitudinal relationship. Results are discussed in terms of their methodological and theoretical implications.
Fosco, Gregory M.; Feinberg, Mark E.
2015-01-01
This study examined the longitudinal implications of adolescents’ exposure to interparental conflict for their developmental success. In the proposed developmental cascade model, adolescents’ perceptions of parental conflict as threatening is a risk factor for diminished self-efficacy, which would account for diminished adjustment. This study presents longitudinal data for 768 6th-grade students and their families over four time points, ending in 8th grade. Analyses were conducted in three steps. First, replication of longitudinal support for threat as a mediator of the link between interparental conflict and emotional distress was found; however, findings did not support threat as a mediator of behavior problems or subjective well-being. Second, threat was found to mediate the longitudinal association between interparental conflict and self-efficacy. Finally, a developmental cascade model supported a risk process in which interparental conflict was related to adolescents’ threat appraisals, which undermined self-efficacy beliefs, and was then linked with emotional distress, behavior problems, and subjective well-being. PMID:25017469
Use of Longitudinal Regression in Quality Control. Research Report. ETS RR-14-31
ERIC Educational Resources Information Center
Lu, Ying; Yen, Wendy M.
2014-01-01
This article explores the use of longitudinal regression as a tool for identifying scoring inaccuracies. Student progression patterns, as evaluated through longitudinal regressions, typically are more stable from year to year than are scale score distributions and statistics, which require representative samples to conduct credibility checks.…
NASA Technical Reports Server (NTRS)
Henderson, W. P.
1978-01-01
An investigation was conducted to determine the effects of wing leading-edge flap deflections on the subsonic longitudinal aerodynamic characteristics of a wing-fuselage configuration with a 44 deg swept wing. The tests were conducted at Mach numbers from 0.40 to 0.85, corresponding to Reynolds numbers (based on wing mean geometric chord) of 2.37 x 1,000,000 to 4.59 x 1,000,000 and at angles of attack from -3 deg to 22 deg. The configurations under study included a wing-fuselage configuration and a wing-fuselage-strake configuration. Each configuration had multisegmented, constant-chord leading-edge flaps which could be deflected independently or in various combinations.
Rolled-up transformer structure for a radiofrequency integrated circuit (RFIC)
Li, Xiuling; Huang, Wen
2016-05-03
A rolled-up transformer structure comprises a multilayer sheet having a rolled configuration comprising multiple turns about a longitudinal axis. The multilayer sheet comprises more than one conductive pattern layer on a strain-relieved layer, including a first conductive film and a second conductive film separated from the first conductive film in a thickness direction. The first conductive film comprises an even number of primary conductive strips, where each primary conductive strip has a length extending in the rolling direction, and the second conductive film comprises an even number of secondary conductive strips, where each secondary conductive strip has a length extending in the rolling direction. In the rolled configuration, turns of the primary conductive strips and turns of the secondary conductive strips wrap around the longitudinal axis. The primary conductive strips serve as a primary winding and the secondary conductive strips serve as a secondary winding of the rolled-up transformer structure.
RECRUITMENT AND RETENTION ISSUES FOR THE NATIONAL CHILDREN'S STUDY
A better understanding of the most effective recruitment techniques and retention strategies for longitudinal, community-based, children's environmental health studies is needed. A series of 18 focus groups were conducted across the U.S. in February 2003. Pregnant women and exp...
MIXED MODELS ANALYSIS OR URBANIZATION LEVEL ON CHLORPYRIFOS EXPOSURE
The National Human Exposure Assessment Survey (NHEXAS) pilot studies were conducted from 1995 through 1997 to examine human population exposure to a wide range of environmental contaminants. In one of the studies, NHEXAS-Maryland, a longitudinal design was used to repeatedly m...
Lundh, Lars-Gunnar; Daukantaité, Daiva; Wångby-Lundh, Margit
2014-01-01
Previous research has established that direct and indirect forms of aggression differ in their association with gender and type of psychological difficulties. One purpose of the present study was to test if the same applies to direct and indirect victimization. A second purpose was to study these associations not only cross-sectionally (as in most previous research) but also longitudinally. A third purpose was to test the hypotheses that there are prospective bidirectional associations not only between victimization and psychological difficulties (which has been shown in previous research), but also between aggression and psychological difficulties, and that direct and indirect forms of aggression and victimization show different associations with different types of psychological difficulties. The participants were a community sample of all students in two grades of regular school in a Swedish municipality who answered questionnaires as part of a two-wave longitudinal study with a one-year interval. The participants were 13-15 years old, and there were longitudinal data on 893 students, which represented 85% of all students. The cross-sectional associations were primarily tested by semi-partial correlations, and the longitudinal associations by hierarchical multiple regression. The results corroborated the meaningfulness of differentiating not only between direct and indirect aggression but also between direct and indirect victimization. Boys reported being more victim to direct aggression, whereas girls reported being more victim to indirect aggression. Direct aggression predicted increased conduct problems in boys, whereas indirect aggression predicted increased conduct problems in girls, and conduct problems reciprocally predicted increased direct and indirect aggression. Indirect victimization showed prospective bidirectional associations with emotional symptoms and conduct problems, suggesting the potential development of vicious cycles of escalating problems in these areas. The present results indicate that direct and indirect aggression, as well as direct and indirect victimization, may have different roles in the development of psychological difficulties in young adolescents. Further, the demonstration of prospective bidirectional associations points to a possible mechanism for the development of psychological difficulties, that may be described in terms of dynamical systems theory. This has potential relevance both for the prevention and the treatment of psychopathology.
Validation of the train energy and dynamics simulator (TEDS).
DOT National Transportation Integrated Search
2015-01-01
FRA has developed Train Energy and Dynamics Simulator (TEDS) based upon a longitudinal train dynamics and operations : simulation model which allows users to conduct safety and risk evaluations, incident investigations, studies of train operations, :...
Meta-Analysis of Effect Sizes Reported at Multiple Time Points Using General Linear Mixed Model.
Musekiwa, Alfred; Manda, Samuel O M; Mwambi, Henry G; Chen, Ding-Geng
2016-01-01
Meta-analysis of longitudinal studies combines effect sizes measured at pre-determined time points. The most common approach involves performing separate univariate meta-analyses at individual time points. This simplistic approach ignores dependence between longitudinal effect sizes, which might result in less precise parameter estimates. In this paper, we show how to conduct a meta-analysis of longitudinal effect sizes where we contrast different covariance structures for dependence between effect sizes, both within and between studies. We propose new combinations of covariance structures for the dependence between effect size and utilize a practical example involving meta-analysis of 17 trials comparing postoperative treatments for a type of cancer, where survival is measured at 6, 12, 18 and 24 months post randomization. Although the results from this particular data set show the benefit of accounting for within-study serial correlation between effect sizes, simulations are required to confirm these results.
NASA Astrophysics Data System (ADS)
Sudicky, E. A.; Illman, W. A.; Goltz, I. K.; Adams, J. J.; McLaren, R. G.
2008-12-01
The spatial variability of hydraulic conductivity in a shallow unconfined aquifer located at North Bay, Ontario composed of glacial-lacustrine and glacial-fluvial sands is examined in exceptional detail and characterized geostatistically. A total of 1878 permeameter measurements were performed at 0.05 m vertical intervals along cores taken from 20 boreholes along two intersecting transect lines. Simultaneous three-dimensional fitting of ln K variogram data to an exponential model yielded geostatistical parameters for the estimation of bulk hydraulic conductivity and solute dispersion parameters. The analysis revealed a ln K variance equal to about 2.0 and three-dimensional anisotropy of the correlation structure of the heterogeneity (λ 1, λ 2 and λ 3 equal to 17.19 m, 7.39 m and 1.0 m, respectively). Effective values of the hydraulic conductivity tensor and the value of the longitudinal macrodispersivity were calculated using the theoretical expressions of Gelhar and Axness (1983). The magnitude of the longitudinal macrodispersivity is reasonably consistent with the observed degree of longitudinal dispersion of the landfill plume along the principal path of migration. The prediction of the transverse dispersion suggests that the transverse-mixing process at the field scale is essentially controlled by local dispersion and diffusion. Variably-saturated 3D flow modeling using the statistically-derived effective hydraulic conductivity tensor allowed a reasonably close calibration to the measured water table and the observed heads at various depths in an array of piezometers. Concomitant transport modeling using the calculated longitudinal macrodispersivity, as well as local-scale values of the transverse dispersion parameters, reasonably predicted the extent and migration rates of the observed contaminant plume that was monitored using a network of multi-level samplers over a period of about 5 years. This study demonstrates that the use of statistically-derived parameters based on stochastic theories results in reliable large-scale 3D flow and transport models for complex hydrogeological systems. This is in agreement with the conclusions reached by Sudicky (1986) at the site of an elaborate tracer test conducted in the aquifer at the Canadian Forces Base Borden. This study represents one of the few attempts at validating stochastic theories of groundwater flow and solute transport in three-dimensions at a site where extensive field data have been collected.
Gaysina, Darya; Fergusson, David M; Leve, Leslie D; Horwood, John; Reiss, David; Shaw, Daniel S; Elam, Kit K; Natsuaki, Misaki N; Neiderhiser, Jenae M; Harold, Gordon T
2013-09-01
Several studies report an association between maternal smoking during pregnancy and offspring conduct disorder. However, past research evidences difficulty in disaggregating prenatal environmental influences from genetic and postnatal environmental influences. To examine the relationship between maternal smoking during pregnancy and offspring conduct problems among children reared by genetically related mothers and genetically unrelated mothers. The following 3 studies using distinct but complementary research designs were used: The Christchurch Health and Development Study (a longitudinal cohort study that includes biological and adopted children), the Early Growth and Development Study (a longitudinal adoption-at-birth study), and the Cardiff IVF (In Vitro Fertilization) Study (an adoption-at-conception study among genetically related families and genetically unrelated families). Maternal smoking during pregnancy was measured as the mean number of cigarettes per day (0, 1-9, or 10) smoked during pregnancy. Possible covariates were controlled for in the analyses, including child sex, birth weight, race/ethnicity, placement age, and breastfeeding, as well as maternal education and maternal age at birth and family breakdown, parenting practices, and family socioeconomic status. Offspring conduct problems (age range, 4-10 years) reported by parents or teachers using the behavior rating scales by Rutter and Conners, the Child Behavior Checklist and the Children's Behavior Questionnaire Short Form, and the Strengths and Difficulties Questionnaire. A significant association between maternal smoking during pregnancy and offspring conduct problems was observed among children reared by genetically related mothers and genetically unrelated mothers. Results from a meta-analysis affirmed this pattern of findings across pooled study samples. Findings across 3 studies using a complement of genetically sensitive research designs suggest that smoking during pregnancy is a prenatal risk factor for offspring conduct problems when controlling for specific perinatal and postnatal confounding factors.
Gaysina, Darya; Fergusson, David M.; Leve, Leslie D.; Horwood, John; Reiss, David; Shaw, Daniel S.; Elam, Kit K.; Natsuaki, Misaki N.; Neiderhiser, Jenae M.; Harold, Gordon T.
2013-01-01
Context A number of studies report an association between maternal smoking during pregnancy and offspring conduct disorder. However, past research evidences difficulty disaggregating prenatal environmental from genetic and postnatal environmental influences. Objective To examine the relationship between maternal smoking during pregnancy and offspring conduct problems among children reared by genetically-related and genetically-unrelated mothers. Design, Setting and Participants Three studies employing distinct but complementary research designs were utilized: The Christchurch Health and Development Study (a longitudinal cohort study that includes biological and adopted children), the Early Growth and Development Study (a longitudinal adoption at birth study), and the Cardiff IVF Study (genetically-related and -unrelated families; an adoption at conception study). Maternal smoking during pregnancy was measured as the average number of cigarettes/day (0, 1–9 or 10+) smoked during pregnancy. A number of possible covariates (child gender, ethnicity, birth weight, breast feeding, maternal age at birth, maternal education, family SES, family breakdown, placement age, and parenting practices) were controlled in the analyses. Main Outcome Measure Child conduct problems (age 4–10 years) reported by parents and/or teachers using the Rutter and Conners behaviour scales, the Child Behavior Checklist and Children's Behavior Questionnaire, and the Strengths and Difficulties Questionnaire. Results A significant association between maternal smoking during pregnancy and child conduct problems was observed among children reared by genetically-related and genetically-unrelated mothers. Results from a meta-analysis affirmed this pattern of findings across pooled study samples. Conclusions Findings across the three studies using a complement of genetically-sensitive research designs suggest smoking during pregnancy is a prenatal risk factor for offspring conduct problems, when specific perinatal and postnatal confounding factors are controlled. PMID:23884431
Religion and body weight: a review of quantitative studies.
Yeary, Karen Hye-Cheon Kim; Sobal, Jeffery; Wethington, Elaine
2017-10-01
Increasing interest in relationships between religion and health has encouraged research about religion and body weight, which has produced mixed findings. We systematically searched 11 bibliographic databases for quantitative studies of religion and weight, locating and coding 85 studies. We conducted a systematic review, analysing descriptive characteristics of the studies as well as relevant religion-body weight associations related to study characteristics. We summarized findings for two categories of religion variables: religious affiliation and religiosity. For religious affiliation, we found evidence for significant associations with body weight in both cross-sectional and longitudinal studies. In particular, Seventh-Day Adventists had lower body weight than other denominations in cross-sectional analyses. For religiosity, significant associations occurred between greater religiosity and higher body weight in both cross-sectional and longitudinal studies. In particular, greater religiosity was significantly associated with higher body weight in bivariate analyses but less so in multivariate analyses. A greater proportion of studies that used a representative sample, longitudinal analyses, and samples with only men reported significant associations between religiosity and weight. Evidence in seven studies suggested that health behaviours and psychosocial factors mediate religion-weight relationships. More longitudinal studies and analyses of mediators are needed to provide stronger evidence and further elucidate religion-weight relationships. © 2017 World Obesity Federation.
Mays, Darren; Gilman, Stephen E; Rende, Richard; Luta, George; Tercyak, Kenneth P; Niaura, Raymond S
2014-06-01
Adolescents with conduct problems are more likely to smoke, and tobacco advertising exposure may exacerbate this risk. Males' excess risk for conduct problems and females' susceptibility to advertising suggest gender-specific pathways to smoking. We investigated the associations between gender, conduct problems, and lifetime smoking and adolescents' exposure to tobacco advertising, and we examined prospective relationships with smoking behaviors. Adolescents completed baseline (2001-2004; n = 541) and 5-year follow-up (2007-2009; n =320) interviews for a family study of smoking risk. Baseline interviews assessed conduct problems and tobacco advertising exposure; smoking behavior was assessed at both timepoints. Generalized linear models analyzed gender differences in the relationship between conduct problems, advertising exposure, and smoking behavior at baseline and longitudinally. At baseline, among males, conduct problems were associated with greater advertising exposure independent of demographics and lifetime smoking. Among females at baseline, conduct problems were associated with greater advertising exposure only among never-smokers after adjusting for demographics. In longitudinal analyses, baseline advertising exposure predicted subsequent smoking initiation (i.e., smoking their first cigarette between baseline and follow-up) for females but not for males. Baseline conduct problems predicted current (i.e., daily or weekly) smoking at follow-up for all adolescents in adjusted models. The findings of this study reinforce that conduct problems are a strong predictor of subsequent current smoking for all adolescents and reveal important differences between adolescent males and females in the relationship between conduct problems, tobacco advertising behavior, and smoking behavior. The findings suggest gender-specific preventive interventions targeting advertising exposure may be warranted.
ERIC Educational Resources Information Center
von Eye, Alexander; Mun, Eun Young; Bogat, G. Anne
2008-01-01
This article reviews the premises of configural frequency analysis (CFA), including methods of choosing significance tests and base models, as well as protecting [alpha], and discusses why CFA is a useful approach when conducting longitudinal person-oriented research. CFA operates at the manifest variable level. Longitudinal CFA seeks to identify…
Briley, Daniel A; Tucker-Drob, Elliot M
2013-09-01
Genes account for increasing proportions of variation in cognitive ability across development, but the mechanisms underlying these increases remain unclear. We conducted a meta-analysis of longitudinal behavioral genetic studies spanning infancy to adolescence. We identified relevant data from 16 articles with 11 unique samples containing a total of 11,500 twin and sibling pairs who were all reared together and measured at least twice between the ages of 6 months and 18 years. Longitudinal behavioral genetic models were used to estimate the extent to which early genetic influences on cognition were amplified over time and the extent to which innovative genetic influences arose with time. Results indicated that in early childhood, innovative genetic influences predominate but that innovation quickly diminishes, and amplified influences account for increasing heritability following age 8 years.
Fu, Xinyuan; Padilla-Walker, Laura M; Brown, Michael N
2017-06-01
The present study examined age-trends and longitudinal bidirectional relations in self-esteem and prosocial behavior toward strangers, friends, and family over a four-year time period (age 11 to 14). A total of 681 adolescents were recruited in the United States (51% girls, 28% single parent families). A longitudinal panel model was conducted and the results showed that adolescent self-esteem was associated longitudinally with subsequent prosocial behavior toward strangers, and earlier prosocial behavior toward strangers promoted subsequent self-esteem. There were no such bidirectional relations between self-esteem and prosocial behavior toward friends and family. Findings also highlight the complexity of adolescent development of selfesteem and the multidimensional nature of prosocial behavior. Discussion focuses on understanding the dynamic interplay between adolescent selfesteem and prosocial behavior. Copyright © 2017 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.
Changing Green Subjectivities in Outdoor and Environmental Education: A Qualitative Study
ERIC Educational Resources Information Center
Preston, Lou
2012-01-01
This article draws on a longitudinal qualitative study of Australian tertiary students studying Outdoor and Environmental Education. It draws on the work of Foucault and Darier to consider how "environmental governmentality" shapes the conduct, desires and attitudes of these students over time. Attention is drawn to normalising and…
ERIC Educational Resources Information Center
Wang, Xueli
2012-01-01
This study examined factors associated with the upward transfer of baccalaureate aspirants beginning at community colleges. Based on data from the National Education Longitudinal Study of 1988 and the Postsecondary Education Transcript Study, a sequential logistic regression analysis was conducted to predict bachelor's degree-seeking community…
ERIC Educational Resources Information Center
Sarkar, Gerlinde
In 1991, the Saskatchewan Institute of Applied Science and Technology (SIAST) initiated a study of factors affecting student persistence, finding that high employment rates in particular sectors were related to higher rates of student attrition. In 1994, a follow-up study was conducted of the career/educational paths of 1,498 respondents from the…
ERIC Educational Resources Information Center
Lazar, Irving; And Others
This report summarizes the findings of the Developmental Continuity Consortium, a collaborative effort of twelve research groups conducting longitudinal studies on the outcomes of early education programs for low-income infants and preschool children initiated in the 1960's. The educational experiments conducted were of three general types: (1)…
ERIC Educational Resources Information Center
Wang, Ming-Te; Kenny, Sarah
2014-01-01
This study used cross-lagged modeling to examine reciprocal relations between maternal and paternal harsh verbal discipline and adolescents' conduct problems and depressive symptoms. Data were from a sample of 976 two-parent families and their children (51% males; 54% European American, 40% African American). Mothers' and fathers'…
Work Redesign and the Job Characteristics Model: A Longitudinal Field Study.
1982-01-01
prior to and following work redesign. Their general job satisfaction , internal work motivation, job performance , conduct, and absenteeism, as well as...increase employee job satisfaction and internal work motivation and improve conduct and job performance , (2) the diagnostic phase is the most essential part...Strength on the Job Performance -Job Satisfaction Relationship . ....... . 117 Summary ....... .................. 119 4. RESEARCH METHODS
ERIC Educational Resources Information Center
Rodgers, Caryn R. R.; Nichols, Tracy R.; Botvin, Gilbert J.
2011-01-01
Increases in substance use prevalence among girls, as well as a lack of research conducted with urban girls of color, highlight the importance of understanding both predictors and outcomes of substance use abstinence (SUA) within this population. This study addresses gaps in SUA research through a longitudinal investigation conducted with urban…
ERIC Educational Resources Information Center
Schnee, Emily
2014-01-01
This longitudinal, qualitative study explores developmental English students' experience of remediation in the context of a first-semester learning community (LC). Conducted at an urban community college in the Northeast, data were collected through semi-structured interviews conducted over a 3-year period with a cohort of 15 students who were…
An airport wind shear detection and warning system using Doppler radar: A feasibility study
NASA Technical Reports Server (NTRS)
Mccarthy, J.; Blick, E. F.; Elmore, K. L.
1981-01-01
A feasibility study was conducted to determine whether ground based Doppler radar could measure the wind along the path of an approaching aircraft with sufficient accuracy to predict aircraft performance. Forty-three PAR approaches were conducted, with 16 examined in detail. In each, Doppler derived longitudinal winds were compared to aircraft measured winds; in approximately 75 percent of the cases, the Doppler and aircraft winds were in acceptable agreement. In the remaining cases, errors may have been due to a lack of Doppler resolution, a lack of co-location of the two sampling volumes, the presence of eddy or vortex like disturbances within the pulse volume, or the presence of point targets in antenna side lobes. It was further concluded that shrouding techniques would have reduced the side lobe problem. A ground based Doppler radar operating in the optically clear air, provides the appropriate longitudinal winds along an aircraft's intended flight path.
Mogasale, Vittal; Mogasale, Vijayalaxmi V; Ramani, Enusa; Lee, Jung Seok; Park, Ju Yeon; Lee, Kang Sung; Wierzba, Thomas F
2016-01-29
The control of typhoid fever being an important public health concern in low and middle income countries, improving typhoid surveillance will help in planning and implementing typhoid control activities such as deployment of new generation Vi conjugate typhoid vaccines. We conducted a systematic literature review of longitudinal population-based blood culture-confirmed typhoid fever studies from low and middle income countries published from 1(st) January 1990 to 31(st) December 2013. We quantitatively summarized typhoid fever incidence rates and qualitatively reviewed study methodology that could have influenced rate estimates. We used meta-analysis approach based on random effects model in summarizing the hospitalization rates. Twenty-two papers presented longitudinal population-based and blood culture-confirmed typhoid fever incidence estimates from 20 distinct sites in low and middle income countries. The reported incidence and hospitalizations rates were heterogeneous as well as the study methodology across the sites. We elucidated how the incidence rates were underestimated in published studies. We summarized six categories of under-estimation biases observed in these studies and presented potential solutions. Published longitudinal typhoid fever studies in low and middle income countries are geographically clustered and the methodology employed has a potential for underestimation. Future studies should account for these limitations.
NASA Astrophysics Data System (ADS)
Gorskii, P. V.
2011-03-01
It is demonstrated that the dependence of Fermi's energy on the magnetic field causes a set of the Shubnikov - de Haas (SDH) oscillation frequencies to change, and their relative contribution to the total longitudinal conductivity of layered crystals depends on whether the scattering of current carriers is isotropic or anisotropic. Owing to the topological transition in a strong magnetic field, Fermi's surface (FS) is transformed from open into closed one and is compressed in the magnetic field direction. Therefore, in an ultraquantum limit, disregarding the Dingle factor, the longitudinal electrical conductivity of the layered crystal tends to zero as a reciprocal square of the magnetic field for the isotropic scattering and as a reciprocal cube of the magnetic field for the anisotropic scattering. All calculations are performed in the approximation of relaxation time considered to be constant versus the quantum numbers for the isotropic scattering and proportional to the longitudinal velocity of current carriers for the anisotropic scattering.
Longitudinal research and data collection in primary care.
van Weel, Chris
2005-01-01
This article reviews examples of and experience with longitudinal research in family medicine. The objective is to use this empirical information to formulate recommendations for improving longitudinal research. The article discusses 3 longitudinal studies from the Nijmegen academic family practice research network: 1 on the prognosis of depression and 1 each on the prognosis of and outcomes of care for type 2 diabetes mellitus. The Nijmegen network has recorded all episodes of morbidity encountered in Dutch family medicine since 1971 in a stable practice population. This network's experience is evaluated to identify lessons that may help other practice-based research networks (PBRNs) in pursuing longitudinal research. In terms of external conditions (conditions related to the general setting), the stability of a population and a high level of continuity of care substantially enhance the ability to perform longitudinal research. In terms of internal conditions (conditions related to the PBRN), motivation of family physicians and their staff to conduct ongoing data collection, and their ownership of the data are key for success. Other critical internal conditions include standardization of data; collection of data by clinician-friendly means; training of family physicians and their staff in data collection, as well as meetings for discussion of this task; provision of feedback to practices on the research findings; use of standard procedures to promote adherence to data collection; availability of facilities for regular measurement of patients' health status or chart review; and use of mechanisms for tracking patients who leave the practice area. Insight from existing experience suggests that longitudinal research can be enhanced in PBRNs. The best way forward is to build longitudinal data collection by drawing on lessons from successful studies. Primary care research policy should advocate for a role of longitudinal research and stimulate its development in PBRNs under favorable population circumstances.
The Changing Workforce. Highlights of the National Study, No. 1.
ERIC Educational Resources Information Center
Galinsky, Ellen; And Others
This report presents results of a nationally representative longitudinal study of nearly 3,400 workers. The study investigated the work and personal/family lives of workers, particularly with respect to recent rapid changes in the economy, layoffs, and downsizing. The study was conducted through a series of hour-long phone interviews. The study…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Halavanau, A.; Piot, P.
2015-06-01
In a cascaded longitudinal space-charge amplifier (LSCA), initial density noise in a relativistic e-beam is amplified via the interplay of longitudinal space charge forces and properly located dispersive sections. This type of amplification process was shown to potentially result in large final density modulations [1] compatible with the production of broadband electromagnetic radiation. The technique was recently demonstrated in the optical domain [2]. In this paper we investigate, via numerical simulations, the performances of a cascaded LSCA beamline at the Fermilab’s Advanced Superconducting Test Accelerator (ASTA). We especially explore the properties of the produced broadband radiation. Our studies have beenmore » conducted with a grid-less three-dimensional space-charge algorithm.« less
Leslie, Eric; Bhargava, Valmik
2012-01-01
A subthreshold pharyngeal stimulus induces lower esophageal sphincter (LES) relaxation and inhibits progression of ongoing peristaltic contraction in the esophagus. Recent studies show that longitudinal muscle contraction of the esophagus may play a role in LES relaxation. Our goal was to determine whether a subthreshold pharyngeal stimulus induces contraction of the longitudinal muscle of the esophagus and to determine the nature of this contraction. Studies were conducted in 16 healthy subjects. High resolution manometry (HRM) recorded pressures, and high frequency intraluminal ultrasound (HFIUS) images recorded longitudinal muscle contraction at various locations in the esophagus. Subthreshold pharyngeal stimulation was induced by injection of minute amounts of water in the pharynx. A subthreshold pharyngeal stimulus induced strong contraction and caudal descent of the upper esophageal sphincter (UES) along with relaxation of the LES. HFIUS identified longitudinal muscle contraction of the proximal (3–5 cm below the UES) but not the distal esophagus. Pharyngeal stimulus, following a dry swallow, blocked the progression of dry swallow-induced peristalsis; this was also associated with UES contraction and descent along with the contraction of longitudinal muscle of the proximal esophagus. We identify a unique pattern of longitudinal muscle contraction of the proximal esophagus in response to subthreshold pharyngeal stimulus, which we propose may be responsible for relaxation of the distal esophagus and LES through the stretch sensitive activation of myenteric inhibitory motor neurons. PMID:22173917
Stern, Adi; Agnew-Blais, Jessica; Danese, Andrea; Fisher, Helen L; Jaffee, Sara R; Matthews, Timothy; Polanczyk, Guilherme V; Arseneault, Louise
2018-05-15
Child maltreatment has consistently been found to be associated with attention deficit/hyperactivity disorder (ADHD). However, the robustness of this association and the direction of the link between maltreatment and ADHD remain unclear. We used data from the Environmental Risk (E-Risk) Longitudinal Twin Study, a cohort of 2232 British twins, to investigate the associations between exposure to abuse/neglect and ADHD in childhood and in young adulthood, and to test their robustness and specificity. We also aimed to test longitudinal associations between abuse/neglect and ADHD from childhood to young adulthood, controlling for confounders. Results indicated strong associations between abuse/neglect and ADHD in childhood and also in young adulthood. In childhood, the association was concentrated among children with comorbid conduct disorder. Longitudinal analyses showed that childhood ADHD predicted abuse/neglect in later years. This association was again concentrated among individuals with comorbid conduct disorder. Abuse/neglect in childhood was not associated with later ADHD in young adulthood after adjusting for childhood ADHD. Our study does not provide support of a causal link between child abuse/neglect and adult ADHD but highlights the possibility of a long-term effect of disruptive behaviors on the risk for experiencing abuse/neglect. These findings emphasize the need for clinicians treating people with ADHD, especially those with comorbid conduct disorder, to be aware of their increased risk for experiencing abuse/neglect. Interventions aimed at reducing risks of abuse/neglect should also focus on the environment of individuals with disruptive behaviors. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.
NASA Astrophysics Data System (ADS)
Oni, T. E.; Omosuyi, G. O.; Akinlalu, A. A.
2017-12-01
Groundwater vulnerability assessment was carried out at Igbara Oke Southwestern Nigeria, with a view to classify the area into vulnerability zones, by applying the electrical resistivity method, using Schlumberger electrode arrays with maximum electrode separation (AB/2) of 65 m in (41) different locations for data acquisition. Geoelectric parameters (layer resistivity and thickness) were determined from the interpreted data. The study area comprises four geoelectric layers (topsoil, lateritic layer, weathered/fractured layer and fresh basement). The geoelectric parameters of the overlying layers across the area were used to assess the vulnerability of the underlying aquifers to near-surface contaminants with the aid of vulnerability maps generated. Three models were compared by maps using geo-electrically derived models; longitudinal conductance, GOD (groundwater occurrence, overlying lithology and depth to the aquifer) and GLSI (geoelectric layer susceptibility indexing). The total longitudinal conductance map shows the north central part of the study area as a weakly protected (0.1-0.19) area, while the northern and southern parts have poor protective capacity (<0.1); this is in agreement with the GOD method which shows the northern part of the study area as less vulnerable (0-0.1) while the southern part has low/moderate (0.1-0.3) vulnerability to contamination. The longitudinal conductance exaggerates the degree of susceptibility to contamination than the GOD and GLSI models. From the models, vulnerability to contamination can be considered higher at the southern part than the northern part and therefore, sources of contamination like septic tank, refuse dump should be cited far from groundwater development area.
Recruitment and retention strategies in longitudinal clinical studies with low-income populations.
Nicholson, Lisa M; Schwirian, Patricia M; Klein, Elizabeth G; Skybo, Theresa; Murray-Johnson, Lisa; Eneli, Ihuoma; Boettner, Bethany; French, Gina M; Groner, Judith A
2011-05-01
Conducting longitudinal research studies with low-income and/or minority participants present a unique set of challenges and opportunities. To outline the specific strategies employed to successfully recruit and retain participants in a longitudinal study of nutritional anticipatory guidance during early childhood, conducted with a low-income, ethnically diverse, urban population of mothers. We describe recruitment and retention efforts made by the research team for the 'MOMS' Study (Making Our Mealtimes Special). The 'multilayered' approach for recruitment and retention included commitment of research leadership, piloting procedures, frequent team reporting, emphasis on participant convenience, incentives, frequent contact with participants, expanded budget, clinical staff buy-in, a dedicated phone line, and the use of research project branding and logos. Barriers to enrollment were not encountered in this project, despite recruiting from a low-income population with a large proportion of African-American families. Process evaluation with clinic staff demonstrated the perception of the MOMS staff was very positive. Participant retention rate was 75% and 64% at 6 months and 12 months post-recruitment, respectively. We attribute retention success largely to a coordinated effort between the research team and the infrastructure support at the clinical sites, as well as project branding and a dedicated phone line. Successful participant recruitment and retention approaches need to be specific and consistent with clinical staff buy in throughout the project. Published by Elsevier Inc.
NASA Technical Reports Server (NTRS)
Henderson, W. P.; Huffman, J. K.
1972-01-01
An investigation has been conducted to determine the effects of wing camber and twist on the longitudinal aerodynamic characteristics of a wingbody configuration. Three wings were used each having the same planform (aspect ratio of 2.5 and leading-edge sweep angle of 44 deg.) but differing in amounts of camber and twist (wing design lift coefficient). The wing design lift coefficients were 0, 0.35, and 0.70. The investigation was conducted over a Mach number range from 0.20 to 0.70 at angles of attack up to about 22 deg. The effect of wing strakes on the aerodynamic characteristics of the cambered wings was also studied. A comparison of the experimentally determined aerodynamic characteristics with theoretical estimates is also included.
Cumulative environmental risk and youth maladjustment: the role of youth attributes.
Gerard, Jean M; Buehler, Cheryl
2004-01-01
Using data from 5,070 youth ages 11 to 18 years old who participated in the National Longitudinal Study of Adolescent Health, concurrent and longitudinal associations among cumulative risk, protective factors, and youth maladjustment were examined. Cumulative risk was associated with concurrent conduct problems and depressed mood. For conduct problems, a compensatory effect was found for scholastic achievement and problem-solving ability. For depressed mood, a compensatory effect was found for scholastic achievement. A protective-reactive effect of self-esteem was found for both forms of maladjustment. Youth gender, grade, and ethnicity moderated these associations. Cumulative risk predicted change over time in depressed mood. Scholastic achievement and self-esteem compensated for this risk. Findings indicate that youth attributes offer limited protection when adolescents experience risk factors across life domains.
NASA Technical Reports Server (NTRS)
Henderson, W. P.
1976-01-01
An investigation was conducted in the Langley low turbulence pressure tunnel to determine the effects of wing leading edge radius and Reynolds number on the longitudinal aerodynamic characteristics of a series of highly swept wing-body configurations. The tests were conducted at Mach numbers below 0.30, angles of attack up to 16 deg, and Reynolds numbers per meter from 6.57 million to 43.27 million. The wings under study in this investigation had leading edge sweep angles of 61.7 deg, 64.61 deg, and 67.01 deg in combination with trailing edge sweep angles of 0 deg and 40.6 deg. The leading edge radii of each wing planform could be varied from sharp to nearly round.
Pine, D S; Cohen, P; Brook, J; Coplan, J D
1997-01-01
OBJECTIVES: This study examined the longitudinal relationship between psychopathology and obesity in young adulthood. METHODS: More than 700 youth in a population-based sample were psychiatrically assessed in 1983 (mean age = 14 years) and 1992 (mean age = 22 years). Self-reported body mass index (BMI) in 1992 was regressed on measures of depression and conduct disorder as well as a set of covariates including indices of physical health, social class, intelligence, and cigarette and alcohol use. Associations were examined with BMI treated as a continuous variable and with a binary index of obesity derived from the BMI distribution in each gender. RESULTS: BMI in young adults was positively related to a number of covariates. With all covariates controlled, BMI was inversely related to adult depressive symptoms in males but not females. BMI was positively related to adolescent symptoms of conduct disorder in both sexes. Similar associations were found between psychiatric symptoms and obesity. CONCLUSIONS: Conduct disorder symptoms in adolescence predicted BMI and obesity in early adulthood. These associations remained after controlling for factors that can affect the association between psychopathology and obesity. PMID:9279265
Parental monitoring in late adolescence: relations to ADHD symptoms and longitudinal predictors.
Salari, Raziye; Thorell, Lisa B
2015-04-01
In this study, we aimed to replicate Stattin and Kerr's (2000) study on parental monitoring and adolescents' deviant behavior, to extend their findings to ADHD symptoms, and to examine the longitudinal predictors (8-18 years) of parental knowledge and child disclosure. Results showed that conduct problems were primarily associated with parental knowledge and child disclosure, but not with parental solicitation and control. A similar pattern was observed for ADHD symptoms. However, while the relations for conduct problems were generally independent of ADHD symptoms, the relations for ADHD symptoms were primarily non-significant after controlling for conduct problems. Moreover, early behavior problems, but not insecure/disorganized attachment, were associated with parental knowledge and child disclosure in adolescence. In conclusion, child disclosure is primarily associated with deviant behavior rather than ADHD, and early child problem behavior is a more important predictor of child disclosure (implicating reciprocal relations between these two constructs) than is insecure/disorganized attachment. Copyright © 2015 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.
Mittal, Ravinder K
2016-09-01
Muscularis propria throughout the entire gastrointestinal tract including the esophagus is comprised of circular and longitudinal muscle layers. Based on the studies conducted in the colon and the small intestine, for more than a century, it has been debated whether the two muscle layers contract synchronously or reciprocally during the ascending contraction and descending relaxation of the peristaltic reflex. Recent studies in the esophagus and colon prove that the two muscle layers indeed contract and relax together in almost perfect synchrony during ascending contraction and descending relaxation of the peristaltic reflex, respectively. Studies in patients with various types of esophageal motor disorders reveal temporal disassociation between the circular and longitudinal muscle layers. We suggest that the discoordination between the two muscle layers plays a role in the genesis of esophageal symptoms, i.e., dysphagia and esophageal pain. Certain pathologies may selectively target one and not the other muscle layer, e.g., in eosinophilic esophagitis there is a selective dysfunction of the longitudinal muscle layer. In achalasia esophagus, swallows are accompanied by the strong contraction of the longitudinal muscle without circular muscle contraction. The possibility that the discoordination between two muscle layers plays a role in the genesis of esophageal symptoms, i.e., dysphagia and esophageal pain are discussed. The purpose of this review is to summarize the regulation and dysregulation of peristalsis by the coordinated and discoordinated function of circular and longitudinal muscle layers in health and diseased states.
2016-01-01
Muscularis propria throughout the entire gastrointestinal tract including the esophagus is comprised of circular and longitudinal muscle layers. Based on the studies conducted in the colon and the small intestine, for more than a century, it has been debated whether the two muscle layers contract synchronously or reciprocally during the ascending contraction and descending relaxation of the peristaltic reflex. Recent studies in the esophagus and colon prove that the two muscle layers indeed contract and relax together in almost perfect synchrony during ascending contraction and descending relaxation of the peristaltic reflex, respectively. Studies in patients with various types of esophageal motor disorders reveal temporal disassociation between the circular and longitudinal muscle layers. We suggest that the discoordination between the two muscle layers plays a role in the genesis of esophageal symptoms, i.e., dysphagia and esophageal pain. Certain pathologies may selectively target one and not the other muscle layer, e.g., in eosinophilic esophagitis there is a selective dysfunction of the longitudinal muscle layer. In achalasia esophagus, swallows are accompanied by the strong contraction of the longitudinal muscle without circular muscle contraction. The possibility that the discoordination between two muscle layers plays a role in the genesis of esophageal symptoms, i.e., dysphagia and esophageal pain are discussed. The purpose of this review is to summarize the regulation and dysregulation of peristalsis by the coordinated and discoordinated function of circular and longitudinal muscle layers in health and diseased states. PMID:27445346
Rolled-up transformer structure for a radiofrequency integrated circuit (RFIC)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Li, Xiuling; Huang, Wen
A rolled-up transformer structure comprises a multilayer sheet having a rolled configuration comprising multiple turns about a longitudinal axis. The multilayer sheet comprises more than one conductive pattern layer on a strain-relieved layer, including a first conductive film and a second conductive film separated from the first conductive film in a thickness direction. The first conductive film comprises an even number of primary conductive strips, where each primary conductive strip has a length extending in the rolling direction, and the second conductive film comprises an even number of secondary conductive strips, where each secondary conductive strip has a length extendingmore » in the rolling direction. In the rolled configuration, turns of the primary conductive strips and turns of the secondary conductive strips wrap around the longitudinal axis. The primary conductive strips serve as a primary winding and the secondary conductive strips serve as a secondary winding of the rolled-up transformer structure.« less
Kimball, A B; Augustin, M; Gordon, K B; Krueger, G G; Pariser, D; Fakharzadeh, S; Goyal, K; Calabro, S; Lee, S; Lin, R; Li, N; Srivastava, B; Guenther, L
2018-05-10
The interdependence between socioeconomic status and disease control in patients with severe psoriasis is not well understood. To assess whether worse disease control among patients with historically severe psoriasis correlated with negative socioeconomic status, we conducted a cross-sectional analysis from Psoriasis Longitudinal Assessment and Registry (PSOLAR), a large, observational study of psoriasis patients receiving, or eligible to receive, conventional systemic or biologic therapies. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
Subsonic wind-tunnel measurements of a slender wing-body configuration employing a vortex flap
NASA Technical Reports Server (NTRS)
Frink, Neal T.
1987-01-01
A wind tunnel study at Mach 0.4 was conducted for a slender wing-body configuration with a leading edge vortex flap of curved planform that is deflectable about a 74 degree swept hinge line. The basic data consist of a unique combination of longitudinal aerodynamic, surface pressure, and vortex flap hinge-moment measurements on a common model. The longitudinal aerodynamic, pressure and hinge-moment data are presented without analysis in tabular format. Plots of the tabulated pressure data are also given.
ERIC Educational Resources Information Center
Pardini, Dustin A.; Fite, Paula J.; Burke, Jeffrey D.
2008-01-01
This study examined the bidirectional relationship between parent and teacher reported conduct problems in youth and parenting practices using a longitudinal sample of boys assessed from 6 to 16 years of age. Analyses tested whether these bidirectional associations changed across development and whether the nature of these associations varied…
Getting in Touch with Paramedic Student Career Intentions
ERIC Educational Resources Information Center
O'Meara, Peter; Tourle, Vianne; Madigan, Veronica; Lighton, David
2012-01-01
Objective: This study of paramedic and nursing/paramedic students aimed to determine the initial career intentions of full-time paramedic students and to identify the key factors that influence their career choices. Design: A longitudinal study design, utilizing surveys and a focus group, was employed. Setting: The study was conducted in an…
Simplified Aircraft-Based Paired Approach: Concept Definition and Initial Analysis
NASA Technical Reports Server (NTRS)
Johnson, Sally C.; Lohr, Gary W.; McKissick, Burnell T.; Abbott, Terence S.; Geurreiro, Nelson M.; Volk, Paul
2013-01-01
Simplified Aircraft-based Parallel Approach (SAPA) is an advanced concept proposed by the Federal Aviation Administration (FAA) to support dependent parallel approach operations to runways with lateral spacing closer than 2500 ft. At the request of the FAA, NASA performed an initial assessment of the potential performance and feasibility of the SAPA concept, including developing and assessing an operational implementation of the concept and conducting a Monte Carlo wake simulation study to examine the longitudinal spacing requirements. The SAPA concept was shown to have significant operational advantages in supporting the pairing of aircraft with dissimilar final approach speeds. The wake simulation study showed that support for dissimilar final approach speeds could be significantly enhanced through the use of a two-phased altitudebased longitudinal positioning requirement, with larger longitudinal positioning allowed for higher altitudes out of ground effect and tighter longitudinal positioning defined for altitudes near and in ground effect. While this assessment is preliminary and there are a number of operational issues still to be examined, it has shown the basic SAPA concept to be technically and operationally feasible.
Mentor or Evaluator? Assisting and Assessing Newcomers to the Professions
ERIC Educational Resources Information Center
Le Maistre, Cathrine; Boudreau, Spencer; Pare, Anthony
2006-01-01
Purpose: A four-year longitudinal study was conducted on the school-to-work transition in four professions traditionally called "helping professions," namely education, social work, occupational therapy, and physiotherapy. One goal of the study was to understand the nature and process of the mentoring relationships that develop and sustain…
Long-Term Teacher Orchestration of Technology-Mediated Collaborative Inquiry
ERIC Educational Resources Information Center
Viilo, Marjut; Seitamaa-Hakkarainen, Pirita; Hakkarainen, Kai
2018-01-01
This explorative case study longitudinally examines teacher orchestration of an inquiry learning process in a technology-enhanced elementary classroom. A 13-month investigative study on cultural artifacts was conducted on 32 fourth grade students who progressed to the fifth grade during the project. The activities were mediated and documented…
REAL-TIME PERSONAL NEPHELOMETER AND TIME ACTIVITY DATA FROM THE NERL RTP PM PANEL STUDY
A longitudinal particulate matter (PM) exposure study was conducted in the Research Triangle Park, NC, area between June 2000 and June 2001. Participants were selected from two groups of potentially susceptible sub-populations: a group of African-Americans living in an environm...
The Developmental Costs of High Self-Esteem for Antisocial Children
ERIC Educational Resources Information Center
Menon, Madhavi; Tobin, Desiree D.; Corby, Brooke C.; Menon, Meenakshi; Hodges, Ernest V. E.; Perry, David G.
2007-01-01
Two hypotheses--high self-esteem leads children to act on antisocial cognitions (disposition-activating hypothesis) and high self-esteem leads children to rationalize antisocial conduct (disposition-rationalizing hypothesis)--were investigated in two longitudinal studies. In Study 1 (N = 189; mean age = 11.1 years), antisocial behavior was…
Brief Report: Associations between Emotional Competence and Adolescent Risky Behavior
ERIC Educational Resources Information Center
Hessler, Danielle M.; Katz, Lynn Fainsilber
2010-01-01
The current study examines associations between emotional competence (i.e., awareness, regulation, comfort with expression) and adolescent risky behavior. Children from a longitudinal study participated at age 9 and 16 (N = 88). Semi-structured interviews were conducted with children about their emotional experiences and coded for areas of…
Chinese Children's Perceptions of Aggression among Peers at School
ERIC Educational Resources Information Center
Wong, Mun
2017-01-01
Recent research suggests that children may encounter aggressive behaviour during the transition from preschool to school. Yet, relatively few longitudinal studies have been conducted on children's perceptions of aggressive behaviour in the transition from preschool to school. This study aims to fill a major gap in the literature by exploring…
Progression of Amygdala Volumetric Abnormalities in Adolescents after Their First Manic Episode
ERIC Educational Resources Information Center
Bitter, Samantha M.; Mills, Neil P.; Adler, Caleb M.; Strakowski, Stephen M.; DelBello, Melissa P.
2011-01-01
Objective: Although previous neuroimaging studies suggest that adolescents with bipolar disorder exhibit smaller amygdala volumes compared with healthy adolescents, whether these abnormalities are present at illness onset or instead develop over time remains unclear. The aim of this study was to conduct a prospective longitudinal investigation…
Teachers' Evaluations of Student Work.
ERIC Educational Resources Information Center
Mead, James V.
This study was conducted to examine the criteria elementary and secondary mathematics teachers use when assigning grades, the visible mark of a teacher's evaluation, when shown individual pieces of mathematics work. Data come from the Teacher Education and Learning to Teach longitudinal study of preservice programs, various types of on-the-job…
Language in Ageing Persons with Down Syndrome.
ERIC Educational Resources Information Center
Rondal, Jean A.; Comblain, Annick
2002-01-01
Several cross-sectional studies and one longitudinal study were conducted on the language abilities of various cohorts of persons with Down syndrome (ages 14-50). A gradual decrease in global cerebral metabolic rate (CMR) for both hemispheres and for each participant was documented, however, no language deterioration could be associated with CMR…
A Longitudinal Approach to Building Theory for Studying Socialization.
ERIC Educational Resources Information Center
McCord, Joan
Theories of socialization have developed independently of established facts against which to measure their adequacy. Studies showing low levels of skin conductance and slow latency of response among criminals have supported a bio-social theory that criminals inherit neurological systems that impede reduction of fear and interfere with learning.…
Faculty Publications and Citations: A Longitudinal Examination
ERIC Educational Resources Information Center
Budd, John M.
2017-01-01
This investigation seeks to study the publication and citation activity of faculty at research universities, as defined by membership in the Association of Research Libraries (ARL). It constitutes the fourth iteration in a study of publishing behaviors, conducted over more than twenty years. The present data indicate a substantial rise in…
Teenage Nutrition and Physique.
ERIC Educational Resources Information Center
Huenemann, Ruth L.; And Others
Body size, composition, and conformation in a teen-age population, and associated factors were studied to obtain useful data for planning programs in public health nutrition. This book describes the purpose, methods, and findings of this four-year longitudinal and cross-sectional study conducted in Berkeley, California, during the years 1961 to…
A series of longitudinal particulate matter (PM) and related co-pollutant human exposure panel field studies have recently been completed. Studies were conducted in Baltimore, Maryland (1997,1998) Fresno, California (1999) and Research Triangle Park, North Carolina (2002-2001)...
GASEOUS CO-POLLUTANTS ASSOCIATED WITH PARTICULATE MATTER-RESULTS FROM THE NERL RTP PM PANEL STUDY
The U.S. EPA National Exposure Research Laboratory (NERL) conducted a longitudinal particulate matter (PM) panel study in Research Triangle Park, NC between June 2000 and June 2001. Participants were selected from two potentially susceptible sub-populations: a multi-racial grou...
Asian-American Parents: Are They Really Different?
ERIC Educational Resources Information Center
Wu, Fang; Qi, Sen
2004-01-01
Using the base year data of parent interviews (n=15,376) conducted by the U. S. Department of Education for the national Early Childhood Longitudinal Study (ECLS-K), this study examined patterns of parenting style of Asian-American parents (n=536) in six domains. Descriptive and ANOVA analyses revealed significant differences between…
An Interactive Model for Studying Student Retention. AIR 1990 Annual Forum Paper.
ERIC Educational Resources Information Center
Glover, Robert H.; Wilcox, Jerry
A design for improving the quality of information available for continuous operational study of student retention at the University of Hartford in Connecticut was examined involving a microcomputer based decision support system for student retention research. The system, an interactive modeling approach to conduct longitudinal and comparative…
Effective Science Instruction: Impact on High-Stakes Assessment Performance
ERIC Educational Resources Information Center
Johnson, Carla C.; Zhang, Danhui; Kahle, Jane Butler
2012-01-01
This longitudinal prospective cohort study was conducted to determine the impact of effective science instruction on performance on high-stakes high school graduation assessments in science. This study provides powerful findings to support authentic science teaching to enhance long-term retention of learning and performance on state-mandated…
Sociocognitive self-regulatory mechanisms governing transgressive behavior.
Bandura, A; Caprara, G V; Barbaranelli, C; Pastorelli, C; Regalia, C
2001-01-01
This longitudinal research examined a structural model of the self-regulatory mechanisms governing transgressive conduct. Perceived academic and self-regulatory efficacy concurrently and longitudinally deterred transgressiveness both directly and by fostering prosocialness and adherence to moral self-sanctions for harmful conduct. The impact of perceived social self-efficacy was mediated through prosocialness. Moral disengagement and prosocialness affected transgressiveness through the mediating influence of irascible affectivity and hostile rumination. Ruminative affectivity, in turn, both concurrently and longitudinally affected transgressiveness. Moral disengagement also contributed independently to variance in transgressiveness over time. This pattern of relations was obtained after controlling for prior transgressiveness. The structural model was replicated across gender and provided a better fit to the data than did several alternative models.
A longitudinal analysis of burnout in middle and high school Korean teachers.
Park, Yang Min; Lee, Sang Min
2013-12-01
This study examines longitudinal relationships among three burnout dimensions in middle and high school teachers. For this study, 419 middle and high school teachers participated in a panel survey, which was conducted in three waves. Using Amos 7.0, we performed autoregressive cross-lagged modeling to obtain a complete picture of the longitudinal relationships among the three factors of the Maslach Burnout Inventory-Educator Survey. Results indicated that the paths from emotional exhaustion at Time1 and Time2 to depersonalization at Time2 and Time3 were statistically significant. In addition, the paths from personal accomplishment at Time1 and Time2 to depersonalization at Time2 and Time3 were also statistically significant. Empirically identifying the process by which burnout occurs could help practitioners and policy makers to design burnout prevention strategies. Copyright © 2012 John Wiley & Sons, Ltd.
Hoffman, K B; Cole, D A; Martin, J M; Tram, J; Seroczynski, A D
2000-11-01
Two cohorts of children and adolescents (who started 6th grade in 1993 and 1996), parents, teachers, and peers participated in a 4-wave, 2-year, longitudinal study of perceived competence and depressive symptoms. The authors assessed children's tendencies to underestimate their competence (discrepant self-appraisals) relative to the appraisals of significant others. We also assessed the degree to which self-appraisals reflected the evaluations of others (reflective self-appraisals). Domains of competence were academic competence, physical appearance, behavioral conduct, social acceptance, and athletic competence. Cross-sectional analyses indicated that depressive symptoms correlated with reflective and discrepant self-appraisals. Longitudinal analyses revealed that reflective and discrepant self-appraisals predicted subsequent depressive symptoms and that depressive symptoms predicted discrepant but not reflective self-appraisals. Clinical implications of the findings are discussed.
Vasavada, Abhay R; Raj, Shetal M; Patel, Udayan; Vasavada, Vaishali; Vasavada, Viraj
2010-01-01
To compare intraoperative performance and postoperative outcome of three phacoemulsification technologies in patients undergoing microcoaxial phacoemulsification through 2.2-mm corneal incisions. The prospective, randomized, single-masked study included 360 eyes randomly assigned to torsional (Infiniti Vision System; Alcon Laboratories, Fort Worth, TX), microburst with longitudinal (Infiniti), or microburst with longitudinal (Legacy Everest, Alcon Laboratories) ultrasound. Assessments included surgical clock time, fluid volume, and intraoperative complications, central corneal thickness on day 1 and months 1 and 3 postoperatively, and endothelial cell density at 3 months postoperatively. Comparisons among groups were conducted. Torsional ultrasound required significantly less surgical clock time and fluid volume than the other groups. There were no intraoperative complications. Change in central corneal thickness and endothelial cell loss was significantly lower in the torsional ultrasound group at all postoperative visits (P < .001, Kruskal-Wallis test) compared to microburst longitudinal ultrasound modalities. Torsional ultrasound demonstrated quantitatively superior intraoperative performance and showed less increase in corneal thickness and less endothelial cell loss compared to microburst longitudinal ultrasound. Copyright 2010, SLACK Incorporated.
Lewis, Gemma; Jones, Peter B; Goodyer, Ian M
2016-02-01
The purpose of this study is to review longitudinal findings on adolescent mental health from the 'ROOTS study', and provide directions and recommendations for future longitudinal research. To do this, we discuss relevant findings from the ROOTS study, and review its strengths and limitations. We examined all publications from the ROOTS study up to July 2015, selected those examining adolescent mental health, and classified them as investigating (a) childhood risk factors for adolescent depression, (b) genetic and cognitive vulnerability to depression in adolescence, (c) genetic markers, childhood adversities, and neuroendophenotypes, (d) morning cortisol and depression, (e) physical activity and depression symptoms, and (f) the underlying structure of mental health in adolescence. We reviewed the strengths and limitations of the ROOTS study, and how they feed into recommendations for future longitudinal research. There was evidence supporting a putative hormonal biomarker for the emergence of depression in boys. Environmental pathways from child adversity to adolescent depression were confirmed in girls, partly accounted for by negative life events in early adolescence. The preceding role of automatic cognitive biases assessed using behavioural tasks was substantiated, with evidence for genetic susceptibility. Novel latent statistical models of child adversity, depression, anxiety, and psychotic experiences were produced, with concurrent and prospective validity. Our experiences conducting the ROOTS study resulted in a set of strengths, limitations, and recommendations for future longitudinal studies. The ROOTS study has advanced knowledge on the aetiology of adolescent depression by investigating environmental, genetic, hormonal, and neural risk factors. Findings provide a foundation for future research integrating cognitive neuroscience with epidemiology.
Yan, Chao; Zhou, Hui; Wei, Wei; Wang, Yi-Ji; Cui, Lixian; Chan, Raymond C K; Deng, Ci-Ping
2018-06-22
We conducted a 4-year longitudinal study to investigate trajectories of attention in a sample of 145 Chinese children. The Test of Everyday Attention was administered and latent growth modeling was used to capture developmental trajectories. We found that children's selective attention showed a linear increase, whereas attentional control and sustained attention increased rapidly then slowed down over 4 years. There was no significant correlation between the slopes of growth model for any subsystems. Girls showed higher initial levels of selective attention than boys, but no difference in growth rate. These findings support different developmental patterns in the attention network systems.
What Happens to a Nursing Home Chain When Private Equity Takes Over? A Longitudinal Case Study.
Bos, Aline; Harrington, Charlene
2017-01-01
We analyzed what happens to a nursing home chain when private equity takes over, with regard to strategy, financial performance, and resident well-being. We conducted a longitudinal (2000-2012) case study of a large nursing home chain that triangulated qualitative and quantitative data from 5 different data sources. Results show that private equity owners continued and reinforced several strategies that were already put in place before the takeover, including a focus on keeping staffing levels low; the new owners added restructuring, rebranding, and investment strategies such as establishing new companies, where the nursing home chain served as an essential "launch customer."
Intrinsic optical conductivity of a {{\\rm{C}}}_{2v} symmetric topological insulator
NASA Astrophysics Data System (ADS)
Sengupta, Parijat; Matsubara, Masahiko; Bellotti, Enrico; Shi, Junxia
2017-07-01
In this work we analytically investigate the longitudinal optical conductivity of the {{{C}}}2v symmetric topological insulator. The conductivity expressions at T = 0 are derived using the Kubo formula and expressed as a function of the ratio of the Dresselhaus and Rashba parameters that characterize the low-energy Hamiltonian. We find that the longitudinal inter-band conductivity vanishes when Dresselhaus and Rashba parameters are equal in strength, also called the persistent spin helix state. The calculations are extended to obtain the frequency-dependent real and imaginary components of the optical conductivity for the topological Kondo insulator SmB6 which exhibits {{{C}}}2v symmetric and anisotropic Dirac cones hosting topological states at \\overline{X} point on the surface Brillouin zone.
Suzuki, Ikuko; Yanagi, Hisako; Tomura, Shigeo
2007-02-01
We conducted a longitudinal study using Functional Independence Measures to clarify factor related to independence of activities of daily living of elderly receiving in-home service under the long-term care insurance system Fifty-four elderly users of the in-home service of Ibaraki Prefecture assented to participate in this study and were analyzed. A researcher conducted survey at the baseline and after follow-up by visiting the elderly at each home. The evaluation standards used here were the Japanese version of Functional Independence Measure (FIM), Mini-Mental State Examination (MMSE), and Geriatric Depression Scale (GDS-15). The FIM score (mean+/-SD) was decreased 83.6+/-36.4 to 81.7+/-37.4 during the 112+/-22.2 day follow up period. Thirty-nine elderly demonstrated improvement or no change in FIM and 15 had declining scores. To clarify independent factors related to FIM change, we conducted a step-wise multifactor logistic regression analysis, and the results suggested importance for "in-home service availability" and "home care period less than one year". Our study suggested that it is important for maintenance or improvement of ADL in home care elderly to provide sufficient home .care services from the beginning under the long-term care insurance system.
2014-01-01
Introduction: Adolescents with conduct problems are more likely to smoke, and tobacco advertising exposure may exacerbate this risk. Males’ excess risk for conduct problems and females’ susceptibility to advertising suggest gender-specific pathways to smoking. We investigated the associations between gender, conduct problems, and lifetime smoking and adolescents’ exposure to tobacco advertising, and we examined prospective relationships with smoking behaviors. Methods: Adolescents completed baseline (2001–2004; n = 541) and 5-year follow-up (2007–2009; n =320) interviews for a family study of smoking risk. Baseline interviews assessed conduct problems and tobacco advertising exposure; smoking behavior was assessed at both timepoints. Generalized linear models analyzed gender differences in the relationship between conduct problems, advertising exposure, and smoking behavior at baseline and longitudinally. Results: At baseline, among males, conduct problems were associated with greater advertising exposure independent of demographics and lifetime smoking. Among females at baseline, conduct problems were associated with greater advertising exposure only among never-smokers after adjusting for demographics. In longitudinal analyses, baseline advertising exposure predicted subsequent smoking initiation (i.e., smoking their first cigarette between baseline and follow-up) for females but not for males. Baseline conduct problems predicted current (i.e., daily or weekly) smoking at follow-up for all adolescents in adjusted models. Conclusions: The findings of this study reinforce that conduct problems are a strong predictor of subsequent current smoking for all adolescents and reveal important differences between adolescent males and females in the relationship between conduct problems, tobacco advertising behavior, and smoking behavior. The findings suggest gender-specific preventive interventions targeting advertising exposure may be warranted. PMID:24590388
Electrical transport properties in Co nanocluster-assembled granular film
NASA Astrophysics Data System (ADS)
Zhang, Qin-Fu; Wang, Lai-Sen; Wang, Xiong-Zhi; Zheng, Hong-Fei; Liu, Xiang; Xie, Jia; Qiu, Yu-Long; Chen, Yuanzhi; Peng, Dong-Liang
2017-03-01
A Co nanocluster-assembled granular film with three-dimensional cross-connection paralleled conductive paths was fabricated by using the plasma-gas-condensation method in a vacuum environment. The temperature-dependent longitudinal resistivity and anomalous Hall effect of this new type granular film were systematically studied. The longitudinal resistivity of the Co nanocluster-assembled granular film first decreased and then increased with increasing measuring temperature, revealing a minimum value at certain temperature, T min . In a low temperature region ( T < T min ), the barrier between adjacent nanoclusters governed the electrical transport process, and the temperature coefficient of resistance (TCR) showed an insulator-type behavior. The thermal fluctuation-induced tunneling conduction progressively increased with increasing temperature, which led to a decrease in the longitudinal resistivity. In a high temperature region, the TCR showed a metallic-type behavior, which was primarily attributed to the temperature-dependent scattering. Different from the longitudinal resistivity behavior, the saturated anomalous Hall resistivity increased monotonically with increasing measuring temperature. The value of the anomalous Hall coefficient ( R S ) reached 2.3 × 10-9 (Ω cm)/G at 300 K, which was about three orders of magnitude larger than previously reported in blocky single-crystal Co [E. N. Kondorskii, Sov. Phys. JETP 38, 977 (1974)]. Interestingly, the scaling relation ( ρx y A ∝ ρx x γ ) between saturated anomalous Hall resistivity ( ρx y A ) and longitudinal resistivity ( ρ x x ) was divided into two regions by T min . However, after excluding the contribution of tunneling, the scaling relation followed the same rule. The corresponding physical mechanism was also proposed to explain these phenomena.
Residents' perceptions of an integrated longitudinal curriculum: a qualitative study.
Lubitz, Rebecca; Lee, Joseph; Hillier, Loretta M
2015-01-01
The purpose of this study was to explore family medicine residents' perceptions of a newly restructured integrated longitudinal curriculum. A purposeful sample of 16 family medicine residents participated in focus group interviews conducted from a grounded theory perspective to identify the characteristics of this training model that contribute to and that challenge learning. Eight key themes were identified: continuity of care, relevance to family medicine, autonomy, program-focused preparation, professional development as facilitated by role modeling, patient volume, clarity of expectations for learners, and logistics. Positive learning experiences were marked by high levels of autonomy, continuity, and relevance to family medicine. Less favorable learning experiences were characterized by limited opportunities for continuity of care, limited relevance to family medicine practice and unclear expectations for the resident's role. Family physician-led learning experiences contributed to residents' understanding of the full scope of family medicine practice, more so than specialist-led experiences. The logistics of implementing the integrated block were challenging and negatively impacted continuity and learning. This study suggests that an integrated longitudinalized family medicine block training model has the potential to support the principles of a longitudinal integrated competency-based curriculum to effectively prepare residents for family medicine practice.
The Pittsburgh Girls Study: Overview and Initial Findings
ERIC Educational Resources Information Center
Keenan, Kate; Hipwell, Alison; Chung, Tammy; Stepp, Stephanie; Stouthamer-Loeber, Magda; Loeber, Rolf; McTigue, Kathleen
2010-01-01
The Pittsburgh Girls Study is a longitudinal, community-based study of 2,451 girls who were initially recruited when they were between the ages of 5 and 8 years. The primary aim of the study was testing developmental models of conduct disorder, major depressive disorder, and their co-occurrence in girls. In the current article, we summarize the…
Auto-ignition of methane-air mixtures flowing along an array of thin catalytic plates
NASA Astrophysics Data System (ADS)
Treviño, C.
2010-12-01
In this paper, the heterogeneous ignition of a methane-air mixture flowing along an infinite array of catalytic parallel plates has been studied by inclusion of gas expansion effects and the finite heat conduction on the plates. The system of equations considers the full compressible Navier-Stokes equations coupled with the energy equations of the plates. The gas expansion effects which arise from temperature changes have been considered. The heterogeneous kinetics considers the adsorption and desorption reactions for both reactants. The limits of large and small longitudinal thermal conductance of the plate material are analyzed and the critical conditions for ignition are obtained in closed form. The governing equations are solved numerically using finite differences. The results show that ignition is more easily produced as the longitudinal wall thermal conductance increases, and the effects of the gas expansion on the catalytic ignition process are rather small due to the large value of the activation energy of the desorption reaction of adsorbed oxygen atoms.
Predictive probability methods for interim monitoring in clinical trials with longitudinal outcomes.
Zhou, Ming; Tang, Qi; Lang, Lixin; Xing, Jun; Tatsuoka, Kay
2018-04-17
In clinical research and development, interim monitoring is critical for better decision-making and minimizing the risk of exposing patients to possible ineffective therapies. For interim futility or efficacy monitoring, predictive probability methods are widely adopted in practice. Those methods have been well studied for univariate variables. However, for longitudinal studies, predictive probability methods using univariate information from only completers may not be most efficient, and data from on-going subjects can be utilized to improve efficiency. On the other hand, leveraging information from on-going subjects could allow an interim analysis to be potentially conducted once a sufficient number of subjects reach an earlier time point. For longitudinal outcomes, we derive closed-form formulas for predictive probabilities, including Bayesian predictive probability, predictive power, and conditional power and also give closed-form solutions for predictive probability of success in a future trial and the predictive probability of success of the best dose. When predictive probabilities are used for interim monitoring, we study their distributions and discuss their analytical cutoff values or stopping boundaries that have desired operating characteristics. We show that predictive probabilities utilizing all longitudinal information are more efficient for interim monitoring than that using information from completers only. To illustrate their practical application for longitudinal data, we analyze 2 real data examples from clinical trials. Copyright © 2018 John Wiley & Sons, Ltd.
Wertz, Jasmin; Agnew-Blais, Jessica; Caspi, Avshalom; Danese, Andrea; Fisher, Helen L; Goldman-Mellor, Sidra; Moffitt, Terrie E; Arseneault, Louise
2018-01-01
Childhood conduct problems are associated with poor functioning in early adulthood. We tested a series of hypotheses to understand the mechanisms underlying this association. We used data from the Environmental Risk (E-Risk) Longitudinal Twin Study, a birth cohort of 2,232 twins born in England and Wales in 1994 and 1995, followed up to age 18 years with 93% retention. Severe conduct problems in childhood were assessed at ages 5, 7, and 10 years using parent and teacher reports. Poor functioning at age 18 years, including cautions and convictions, daily cigarette smoking, heavy drinking, and psychosocial difficulties, was measured through interviews with participants and official crime record searches. Participants 18 years old with versus without a childhood history of severe conduct problems had greater rates of each poor functional outcome, and they were more likely to experience multiple poor outcomes. This association was partly accounted for by concurrent psychopathology in early adulthood, as well as by early familial risk factors, both genetic and environmental. Childhood conduct problems, however, continued to predict poor outcomes at age 18 years after accounting for these explanations. Children with severe conduct problems display poor functioning at age 18 years because of concurrent problems in early adulthood and familial risk factors originating in childhood. However, conduct problems also exert a lasting effect on young people's lives independent of these factors, pointing to early conduct problems as a target for early interventions aimed at preventing poor functional outcomes. Copyright © 2017 American Academy of Child and Adolescent Psychiatry. Published by Elsevier Inc. All rights reserved.
Choi, Sunha H
2012-04-01
This study tested a healthy immigrant effect (HIE) and postimmigration health status changes among late life immigrants. Using three waves of the Second Longitudinal Study of Aging (1994-2000) and the linked mortality file through 2006, this study compared (a) chronic health conditions, (b) longitudinal trajectories of self-rated health, (c) longitudinal trajectories of functional impairments, and (d) mortality between three groups (age 70+): (i) late life immigrants with less than 15 years in the United States (n = 133), (ii) longer term immigrants (n = 672), and (iii) U.S.-born individuals (n = 8,642). Logistic and Poisson regression, hierarchical generalized linear modeling, and survival analyses were conducted. Late life immigrants were less likely to suffer from cancer, had lower numbers of chronic conditions at baseline, and displayed lower hazards of mortality during the 12-year follow-up. However, their self-rated health and functional status were worse than those of their counterparts over time. A HIE was only partially supported among older adults.
Biofilm formation and ethanol inhibition by bacterial contaminants of biofuel fermentation
USDA-ARS?s Scientific Manuscript database
Bacterial contaminants can inhibit ethanol production in biofuel fermentations, and even result in stuck fermentations. Contaminants may persist in production facilities by forming recalcitrant biofilms. A two-year longitudinal study was conducted of bacterial contaminants from a Midwestern dry grin...
TRACER DISPERSION STUDIES FOR HYDRAULIC CHARACTERIZATION OF PIPES
A series of experiments were conducted at the U. S. Environmental Protection Agency (EPA) Test & Evaluation (T&E) Facility in Cincinnati, Ohio, to quantify longitudinal dispersion of a sodium fluoride tracer in polyvinyl chloride (PVC) pipe and ductile iron pipe under laminar, tr...
2011-12 National Postsecondary Student Aid Study (NPSAS:12). Data File Documentation. NCES 2014-182
ERIC Educational Resources Information Center
Wine, Jennifer; Bryan, Michael; Siegel, Peter
2013-01-01
This report describes the methods and results for the 2011-12 National Postsecondary Student Aid Study (NPSAS:12), conducted for the U.S. Department of Education's National Center for Education Statistics (NCES), Washington, DC. The following legislation authorizes this and previous cycles of NPSAS, as well as two longitudinal studies deriving…
HIV/AIDS Infected Mothers' Experience of a Group Intervention to Enhance Their Children's Behavior
ERIC Educational Resources Information Center
Eloff, Irma; Finestone, Michelle; Forsyth, Brian
2016-01-01
A secondary study was conducted within a broader National Institutes of Health (NIH)-funded longitudinal study on resilience in South African mothers and children affected by HIV/AIDS (Human Immunodeficiency Virus/Acquired Immune Deficiency Syndrome). The aim of this study was to evaluate the effect of a 24-week support group intervention…
ERIC Educational Resources Information Center
Higgs, Philip; Keevy, James
2007-01-01
This article reflects on the reliability of the evidence contained in the National Qualifications Framework Impact Study, a longitudinal comparative study conducted by the South African Qualifications Authority since 2002. In so doing, the veracity of evidence-based research in determining the impact of the South African Qualifications Framework…
A Longitudinal Study of Mass Media Development in Less-Developed Countries.
ERIC Educational Resources Information Center
Shah, Hemant
A study was conducted to examine the causal predictors of mass media development in 105 underdeveloped countries for various lengths of time to determine if there were consistent relationships among the dependent and independent variables regardless of the time lag. The study also sought to determine how mass media developed during the 29-year…
Computer Access and Computer Use for Science Performance of Racial and Linguistic Minority Students
ERIC Educational Resources Information Center
Chang, Mido; Kim, Sunha
2009-01-01
This study examined the effects of computer access and computer use on the science achievement of elementary school students, with focused attention on the effects for racial and linguistic minority students. The study used the Early Childhood Longitudinal Study (ECLS-K) database and conducted statistical analyses with proper weights and…
The Impact of Parental Religiosity on Parenting Goals and Parenting Style: A Dutch Perspective
ERIC Educational Resources Information Center
Vermeer, Paul
2011-01-01
Several studies, conducted mainly in the United States, have revealed that parental religiosity influences the way parents raise their children. Against this background, the current study explores if such an effect is also discernible in the Netherlands. Data were gathered as part of a longitudinal study, in which 356 Dutch parents answered…
ERIC Educational Resources Information Center
Tucker, Mark; Weaver, Debbi
2013-01-01
Students returning from an international business study tour program were interviewed about their experiences and perceptions of the professional and personal impact of the program. When interviews were conducted within 3-4 months of the students' return, mixed responses were received, with some students highly positive about their experiences,…
Assessment of Thermal Performance of Functionally Graded Materials in Longitudinal Fins
NASA Astrophysics Data System (ADS)
Hassanzadeh, R.; Bilgili, M.
2018-01-01
Assessment of the thermal characteristics of materials in heat exchangers with longitudinal fins is performed in the case where a conventional homogeneous material of a longitudinal fin is replaced by a functionally graded one, in which the fin material properties, such as the conductivity, are assumed to be graded as linear and power-law functions along the normal axis from the fin base to the fin tip. The resulting equations are calculated under two (Dirichlet and Neumann) boundary conditions. The equations are solved by an approximate analytical method with the use of the mean value theorem. The results show that the inhomogeneity index of a functionally graded material plays an important role for the thermal energy characteristics in such heat exchangers. In addition, it is observed that the use of such a material in longitudinal fins enhances the rate of heat transfer between the fin surface and surrounding fluid. Hopefully, the results obtained in the study will arouse interest of designers in heat exchange industry.
Hurwitz, Lisa B.; Schmitt, Kelly L.; Olsen, Megan K.
2017-01-01
Recruiting children and families for research studies can be challenging, and re-recruiting former participants for longitudinal research can be even more difficult, especially when a study was not prospectively designed to encompass continuous data collection. In this article, we explain how researchers can set up initial studies to potentially facilitate later waves of data collection; locate former study participants using newer, often digital, tools; schedule families using recruitment phone/email/mail scripts that highlight the many benefits to continued study participation; and confirm appointments with other digital tools. We draw from prior methodological and longitudinal pieces to provide suggestions to others wishing to re-recruit families for longitudinal studies. In addition, we draw upon our own experience conducting a non-prospective longitudinal study 6 years after an educational intervention, in which we successfully re-located 122 (90%) and interviewed 101 of 136 (83% of the located sample and 74% of the full original sample) parents and their early adolescent children. Although the majority of participants were recruited via original contact information (especially phone numbers), using a range of strategies to recruit (e.g., search engines focused on contact information, social media) and motivate participation (e.g., multifaceted phone/email/mail scheduling scripts, flexibility in location and means of participation) yielded a more desirable sample size at relatively low costs. PMID:28955265
A longitudinal particulate matter (PM) exposure study was conducted in the Research Triangle Park, NC area between June 2000 and June 2001. Participants were selected from two groups of potentially susceptible sub-populations: a group of African-Americans living in an environme...
A longitudinal particulate matter (PM) exposure study sponsored by EPA's National Exposure Research Laboratory (NERL) was conducted in the Research Triangle Park, NC area between June 2000 and June 2001. Participants were selected from two groups of potentially susceptible sub-...
Exploring Student, Family, and School Predictors of Self-Determination Using NLTS2 Data
ERIC Educational Resources Information Center
Shogren, Karrie A.; Garnier Villarreal, Mauricio; Dowsett, Chantelle; Little, Todd D.
2016-01-01
This study conducted secondary analysis of data from the National Longitudinal Transition Study-2 (NLTS2) to examine the degree to which student, family, and school constructs predicted self-determination outcomes. Multi-group structural equation modeling was used to examine predictive relationships between 5 students, 4 family, and 7 school…
Exploring Student, Family, and School Predictors of Self-Determination Using NLTS2 Data
ERIC Educational Resources Information Center
Shogren, Karrie A.; Garnier Villarreal, Mauricio; Dowsett, Chantelle; Little, Todd D.
2016-01-01
This study conducted secondary analysis of data from the National Longitudinal Transition Study-2 (NLTS2) to examine the degree to which student, family, and school constructs predicted self-determination outcomes. Multi-group structural equation modeling was used to examine predictive relationships between 5 student, 4 family, and 7 school…
The Transition of Divorce: An Analysis of Public Policy.
ERIC Educational Resources Information Center
Duffy, Mary E.; Jorgensen, Karen
A growing number of families are headed by single women. A longitudinal study was conducted to identify major goals of these women. Data from mailed questionnaires and telephone interviews were collected from 136 divorced women. Results from the first year of the study revealed the goal most often identified by the women was financial…
ERIC Educational Resources Information Center
Saçkes, Mesut; Trundle, Kathy Cabe
2017-01-01
This longitudinal study examined the role of metaconceptual awareness in the change and the durability of preservice teachers' conceptual understandings over the course of several months. Sixteen preservice early childhood teachers participated in the study. Semi-structured interviews were conducted to reveal the participants' conceptual…
The Job Responsibilities Scale: Invariance in a Longitudinal Prospective Study.
ERIC Educational Resources Information Center
Ludlow, Larry H.; Lunz, Mary E.
1998-01-01
The degree of invariance of the Job Responsibilities Scale for medical technologists was studied for 1993 and 1995, conducting factor analyses of data from each year (1063 and 665 individuals, respectively). Nearly identical factor patterns were found, and Rasch rating scale analyses found nearly identical pairs of item estimates. Implications are…
Measuring Variability and Change with an Item Response Model for Polytomous Variables.
ERIC Educational Resources Information Center
Eid, Michael; Hoffman, Lore
1998-01-01
An extension of the graded-response model of F. Samejima (1969) is presented for the measurement of variability and change. The model is illustrated with a longitudinal study of student interest in radioactivity conducted with about 1,200 German students in elementary school when the study began. (SLD)
Early Temperamental Antecedents of Adult Type A Behaviors.
ERIC Educational Resources Information Center
Steinberg, Laurence
1985-01-01
Data for this study of 108 young adults from the New York Longitudinal Study include measures of temperament derived from two sources: interviews conducted with subjects' mothers when the children were 3 and 4 years of age and measures of Type A behavior derived from interviews with the subjects during young adulthood. (Author/NH)
Aircraft and avionic related research required to develop an effective high-speed runway exit system
NASA Technical Reports Server (NTRS)
Schoen, M. L.; Hosford, J. E.; Graham, J. M., Jr.; Preston, O. W.; Frankel, R. S.; Erickson, J. B.
1979-01-01
Research was conducted to increase airport capacity by studying the feasibility of the longitudinal separation between aircraft sequences on final approach. The multidisciplinary factors which include the utility of high speed exits for efficient runway operations were described along with recommendations and highlights of these studies.
Advances in Research on Organization Development: Toward a Beginning
ERIC Educational Resources Information Center
Pate, Larry E.; And Others
1977-01-01
This paper examines 38 research studies that were conducted on various aspects of organization development (OD) technology. The studies are compared along eight dimensions. Problems associated with evaluating OD and the limited amount of OD research are discussed. It is argued that more systematic, longitudinal research on OD is needed. (Author)
Reciprocal Relationships between Job Resources, Personal Resources, and Work Engagement
ERIC Educational Resources Information Center
Xanthopoulou, Despoina; Bakker, Arnold B.; Demerouti, Evangelia; Schaufeli, Wilmar B.
2009-01-01
This study examined longitudinal relationships between job resources, personal resources, and work engagement. On the basis of Conservation of Resources theory, we hypothesized that job resources, personal resources, and work engagement are reciprocal over time. The study was conducted among 163 employees, who were followed-up over a period of 18…
Religious Life-Styles and Mental Health: A Follow-Up Study.
ERIC Educational Resources Information Center
Masters, Kevin S.; And Others
1991-01-01
Conducted study as part of longitudinal research project designed to discover more about the relations between religious involvement and mental health. Collected data through semistructured interviews and a psychological test battery from 56 religious young adults in a 3-year followup. Revealed lack of evidence of link between orthodox religiosity…
What Do We Know about Transfer?
ERIC Educational Resources Information Center
Palmer, James
1991-01-01
A small number of studies conducted during the 1980's provide insights into the magnitude of transfer activity and the characteristics of students who are likely to transfer. The studies, based occasionally on state data and more frequently on secondary analyses of the U.S. Department of Education's longitudinal databases, reveal that: (1)…
ERIC Educational Resources Information Center
Petcu, Stefania D.; Van Horn, M. Lee; Shogren, Karrie A.
2017-01-01
This study conducted a secondary analysis using data from the "National Longitudinal Transition Study-2" (NLTS-2) to examine the degree to which three of the four essential characteristics of self-determination (autonomy, psychological empowerment, and self-realization) predict enrollment in, and completion of, postsecondary education…
Toward Improving Research in Social Studies Education. SSEC Monograph Series.
ERIC Educational Resources Information Center
Fraenkel, Jack R.; Wallen, Norman E.
Social studies research has been criticized for sampling bias, inappropriate methodologies, incorrect or inappropriate use of statistics, weak or ill-defined treatments, and lack of replication and/or longitudinal follow-up. In an effort to ascertain whether past criticisms were true of current research as well, a review was conducted of 118…
Cognitive Evolution by MMSE in Poststroke Patients
ERIC Educational Resources Information Center
da Costa, Fabricia Azevedo
2010-01-01
The aim of this study was to investigate the cognitive and clinical evolution of post-acute stroke patients and the evolution of each Mini-Mental State Examination (MMSE) item. A longitudinal study was conducted with 42 poststroke individuals in rehabilitation. The MMSE and the National Institutes of Health Stroke Scale were used to assess…
The "Synergies" Research-Practice Partnership Project: A "2020 Vision" Case Study
ERIC Educational Resources Information Center
Falk, John H.; Dierking, Lynn D.; Staus, Nancy L.; Wyld, Jennifer N.; Bailey, Deborah L.; Penuel, William R.
2016-01-01
This paper, describes "Synergies," an on-going longitudinal study and design effort, being conducted in a diverse, under-resourced community in Portland, Oregon, with the goal of measurably improving STEM learning, interest and participation by early adolescents, both in school and out of school. Authors examine how the work of this…
Reciprocal relations between workplace bullying, anxiety, and vigor: a two-wave longitudinal study.
Rodríguez-Muñoz, Alfredo; Moreno-Jiménez, Bernardo; Sanz-Vergel, Ana Isabel
2015-01-01
Workplace bullying has been classified as an extreme social stressor in work contexts and has been repeatedly linked to several negative consequences. However, little research has examined reversed or reciprocal relations of bullying and outcomes. We conducted a two-wave longitudinal study with a time lag of six months. The study sample consisted of 348 employees of the Spanish workforce. The present study examined longitudinal relationships between workplace bullying, psychological health, and well-being. On the basis of conservation of resources theory, we hypothesized that we would find reciprocal relations among study variables over time. Results of cross-lagged structural equation modeling analyses supported our hypotheses. Specifically, it was found that Time 1 (T1) workplace bullying was negatively related to Time 2 (T2) vigor and positively related to T2 anxiety. Additionally, T1 anxiety and vigor had an effect on T2 workplace bullying. Overall, these findings support the validity of the theoretical models postulating a reciprocal bullying-outcome relationship, rather than simple one-way causal pathways approaches.
2010-01-01
Background There is an increasing trend towards lower participation in questionnaire surveys. This reduces representativeness, increases costs and introduces particular challenges to longitudinal surveys, as researchers have to use complex statistical techniques which attempt to address attrition. This paper describes a trial of incentives to retain longitudinal survey cohorts from ages 16 to 20, to question them on the sensitive topic of sexual health. Methods A longitudinal survey was conducted with 8,430 eligible pupils from two sequential year groups from 25 Scottish schools. Wave 1 (14 years) and Wave 2 (16 years) were conducted largely within schools. For Wave 3 (18 years), when everyone had left school, the sample was split into 4 groups that were balanced across predictors of survey participation: 1) no incentive; 2) chance of winning one of twenty-five vouchers worth £20; 3) chance of winning one £500 voucher; 4) a definite reward of a £10 voucher sent on receipt of their completed questionnaire. Outcomes were participation at Wave 3 and two years later at Wave 4. Analysis used logistic regression and adjusted for clustering at school level. Results The only condition that had a significant and beneficial impact for pupils was to offer a definite reward for participation (Group 4). Forty-one percent of Group 4 participated in Wave 3 versus 27% or less for Groups 1 to 3. At Wave 4, 35% of Group 4 took part versus 25% or less for the other groups. Similarly, 22% of Group 4 participated in all four Waves of the longitudinal study, whereas for the other three groups it was 16% or less that participated in full. Conclusions The best strategy for retaining all groups of pupils and one that improved retention at both age 18 and age 20 was to offer a definite reward for participation. This is expensive, however, given the many benefits of retaining a longitudinal sample, we recommend inclusion of this as a research cost for cohort and other repeat-contact studies. PMID:20109221
Makarem, Nour; Nicholson, Joseph M.; Bandera, Elisa V.; McKeown, Nicola M.
2016-01-01
Context: Evidence from previous reviews is supportive of the hypothesis that whole grains may protect against various cancers. However, the reviews did not report risk estimates for both whole grains and cereal fiber and only case–control studies were evaluated. It is unclear whether longitudinal studies support this conclusion. Objective: To evaluate associations between whole grains and cereal fiber in relation to risk of lifestyle-related cancers data from longitudinal studies was evaluated. Data Sources: The following 3 databases were systematically searched: PubMed, EMBASE, and Cochrane CENTRAL. Study Selection: A total of 43 longitudinal studies conducted in Europe and North America that reported multivariable-adjusted risk estimates for whole grains (n = 14), cereal fiber (n = 23), or both (n = 6) in relation to lifestyle-related cancers were included. Data Extraction: Information on study location, cohort name, follow-up duration, sample characteristics, dietary assessment method, risk estimates, and confounders was extracted. Data Synthesis: Of 20 studies examining whole grains and cancer, 6 studies reported a statistically significant 6%–47% reduction in risk, but 14 studies showed no association. Of 29 studies examining cereal fiber intake in relation to cancer, 8 showed a statistically significant 6%–49% reduction in risk, whereas 21 studies reported no association. Conclusions: This systematic review concludes that most studies were suggestive of a null association. Whole grains and cereal fiber may protect against gastrointestinal cancers, but these findings require confirmation in additional studies. PMID:27257283
Effect of Thyrotropin Suppression Therapy on Bone in Thyroid Cancer Patients
Hawley, Sarah T.; Haymart, Megan R.
2016-01-01
Background. The thyroid cancer incidence is rising. Despite current guidelines, controversy exists regarding the degree and duration of thyrotropin suppression therapy. Also, its potential skeletal effects remain a concern to physicians caring for thyroid cancer patients. We conducted a review of published data to evaluate existing studies focusing on the skeletal effects of thyrotropin suppression therapy in thyroid cancer patients. Materials and Methods. A systematic search of the PubMed, Ovid/Medline, and Cochrane Central Register of Controlled Trials databases was conducted. The retained studies were evaluated for methodological quality, and the study populations were categorized into premenopausal women, postmenopausal women, and men. Results. Twenty-five pertinent studies were included. Seven studies were longitudinal and 18 were cross-sectional. Of the 25 included studies, 13 were assigned an excellent methodological quality score. Three of 5 longitudinal studies and 3 of 13 cross-sectional studies reported decreased bone mineral density (BMD) in premenopausal women; 2 of 4 longitudinal studies and 5 of 13 cross-sectional studies reported decreased BMD in postmenopausal women. The remaining studies showed no effect on BMD. The only longitudinal study of men showed bone mass loss; however, cross-sectional studies of men did not demonstrate a similar effect. Conclusion. Studies to date have yielded conflicting results on the skeletal effects of thyrotropin suppression therapy and a knowledge gap remains, especially for older adults and men. Existing data should be cautiously interpreted because of the variable quality and heterogeneity. Identifying groups at risk of adverse effects from thyrotropin suppression therapy will be instrumental to providing focused and tailored thyroid cancer treatment. Implications for Practice: The standard treatment for thyroid cancer includes total thyroidectomy with or without radioactive iodine ablation, often followed by thyrotropin suppression therapy. Despite current guidelines, controversy exists regarding the degree and duration of thyrotropin suppression therapy, and discordant results have been reported on its adverse effects on bone. The present review provides physicians with existing data on the skeletal effects of thyrotropin suppression therapy, highlighting the need for further research to identify the groups at risk of adverse skeletal effects. This knowledge will aid in developing tailored thyroid cancer treatment. PMID:26659220
Effect of Thyrotropin Suppression Therapy on Bone in Thyroid Cancer Patients.
Papaleontiou, Maria; Hawley, Sarah T; Haymart, Megan R
2016-02-01
The thyroid cancer incidence is rising. Despite current guidelines, controversy exists regarding the degree and duration of thyrotropin suppression therapy. Also, its potential skeletal effects remain a concern to physicians caring for thyroid cancer patients. We conducted a review of published data to evaluate existing studies focusing on the skeletal effects of thyrotropin suppression therapy in thyroid cancer patients. A systematic search of the PubMed, Ovid/Medline, and Cochrane Central Register of Controlled Trials databases was conducted. The retained studies were evaluated for methodological quality, and the study populations were categorized into premenopausal women, postmenopausal women, and men. Twenty-five pertinent studies were included. Seven studies were longitudinal and 18 were cross-sectional. Of the 25 included studies, 13 were assigned an excellent methodological quality score. Three of 5 longitudinal studies and 3 of 13 cross-sectional studies reported decreased bone mineral density (BMD) in premenopausal women; 2 of 4 longitudinal studies and 5 of 13 cross-sectional studies reported decreased BMD in postmenopausal women. The remaining studies showed no effect on BMD. The only longitudinal study of men showed bone mass loss; however, cross-sectional studies of men did not demonstrate a similar effect. Studies to date have yielded conflicting results on the skeletal effects of thyrotropin suppression therapy and a knowledge gap remains, especially for older adults and men. Existing data should be cautiously interpreted because of the variable quality and heterogeneity. Identifying groups at risk of adverse effects from thyrotropin suppression therapy will be instrumental to providing focused and tailored thyroid cancer treatment. The standard treatment for thyroid cancer includes total thyroidectomy with or without radioactive iodine ablation, often followed by thyrotropin suppression therapy. Despite current guidelines, controversy exists regarding the degree and duration of thyrotropin suppression therapy, and discordant results have been reported on its adverse effects on bone. The present review provides physicians with existing data on the skeletal effects of thyrotropin suppression therapy, highlighting the need for further research to identify the groups at risk of adverse skeletal effects. This knowledge will aid in developing tailored thyroid cancer treatment. ©AlphaMed Press.
Life Skills Training for Middle and High School Students with Autism
ERIC Educational Resources Information Center
Chiang, Hsu-Min; Ni, Xinyu; Lee, Young-Sun
2017-01-01
This study investigated the extent to which life skills training was offered to middle and high school students with autism and life skills training needs after high school. A secondary analysis of the National Longitudinal Training Study-2 (NLTS-2) data was conducted in this study. This study found that the majority of the middle and high school…
Teacher's Experience from Collaborative Design: Reported Impact on Professional Development
ERIC Educational Resources Information Center
Svendsen, Bodil
2017-01-01
This article is based on a research and development project conducted in one upper secondary school in Norway. The participating teachers have been part of a three year longitudinal study, and the findings in the present study are from their third and final year of a professional development study. The aim of this study was to find out how…
The U.S. Environmental Protection Agency's (EPA) National Exposure Research Laboratory (NERL) is conducting a study of young children's exposures to chemicals in the home. The American Chemistry Council (ACC) is partnering with the EPA to enhance an existing EPA study of childre...
Measuring end-of-life care outcomes prospectively.
Steinhauser, Karen E
2005-01-01
This paper discusses the state of the science in prospective measurement in end-of-life research and identifies particular areas for focused attention. Topics include defining the scope of inquiry, evaluating experiences of patients too ill to communicate, the role of proxy and family response, measurement sensitivity to change, the role of theory in guiding measurement efforts, evaluating relationships between domains of end-of-life experience, and measurement of cultural comprehensiveness. The state of the sciences calls for future research to (1) conduct longitudinal studies to capture transitions in end-of-life trajectories; (2) evaluate the quality of proxy reporting as it varies by rater relationship, domain, and over time; (3) use state-of-the art psychometric and longitudinal techniques to validate measures and to assess sensitivity to change; (4) develop further and test conceptual models of the experience of dying; (5) study the inter-relatedness of multiple dimensions of end-of-life trajectories; (6) compile updated information evaluating available measurement tools; and (7) conduct population- based research with attention to ethnic and age diversity.
NASA Technical Reports Server (NTRS)
Ashby, G. C., Jr.
1973-01-01
A scale model of the North American Rockwell ATP Orbiter with and without the external tank has been tested in a 22-inch helium tunnel at Mach 20 and a Reynolds number based on model length, of 2.14 times one million. Longitudinal and lateral-directional data were determined for the orbiter alone while only longitudinal characteristics and elevon roll effectiveness were investigated for the orbiter/tank combination. Oil flow and electron beam flow visualization studies were conducted for the orbiter alone, orbiter with external tank and the ascent configuration.
NASA Astrophysics Data System (ADS)
Sazykin, S.; Wolf, R.; Spiro, R.; Fejer, B.
Ionospheric prompt penetration electric fields of magnetospheric origin, together with the atmospheric disturbance dynamo, represent the most important parameters controlling the storm-time dynamics of the low and mid-latitude ionosphere. These prompt penetration fields result from the disruption of region-2 field-aligned shielding currents during geomagnetically disturbed conditions. Penetration electric fields con- trol, to a large extent, the generation and development of equatorial spread-F plasma instabilities as well as other dynamic space weather phenomena in the ionosphere equatorward of the auroral zone. While modeling studies typically agree with average patterns of prompt penetration fields, experimental results suggest that longitudinal variations of the ionospheric con- ductivities play a non-negligible role in controlling spread-F phenomena, an effect that has not previously been modeled. We present first results of modeling prompt pene- tration electric fields using a version of the Rice Convection Model (RCM) that allows for longitudinal variations in the ionospheric conductance tensor. The RCM is a first- principles numerical ionosphere-magnetosphere coupling model that solves for the electric fields, field-aligned currents, and particle distributions in the ionosphere and inner/middle magnetosphere. We compare these new theoretical results with electric field observations.
Efficient three-dimensional Poisson solvers in open rectangular conducting pipe
NASA Astrophysics Data System (ADS)
Qiang, Ji
2016-06-01
Three-dimensional (3D) Poisson solver plays an important role in the study of space-charge effects on charged particle beam dynamics in particle accelerators. In this paper, we propose three new 3D Poisson solvers for a charged particle beam in an open rectangular conducting pipe. These three solvers include a spectral integrated Green function (IGF) solver, a 3D spectral solver, and a 3D integrated Green function solver. These solvers effectively handle the longitudinal open boundary condition using a finite computational domain that contains the beam itself. This saves the computational cost of using an extra larger longitudinal domain in order to set up an appropriate finite boundary condition. Using an integrated Green function also avoids the need to resolve rapid variation of the Green function inside the beam. The numerical operational cost of the spectral IGF solver and the 3D IGF solver scales as O(N log(N)) , where N is the number of grid points. The cost of the 3D spectral solver scales as O(Nn N) , where Nn is the maximum longitudinal mode number. We compare these three solvers using several numerical examples and discuss the advantageous regime of each solver in the physical application.
Childhood self-control and adult outcomes: results from a 30-year longitudinal study.
Fergusson, David M; Boden, Joseph M; Horwood, L John
2013-07-01
A study by Moffitt et al. reported pervasive associations between childhood self-control and adult outcomes. The current study attempts to replicate the findings reported by Moffitt et al., adjusting these results for the confounding influence of childhood conduct problems. Data were gathered from the Christchurch Health and Development Study, a longitudinal birth cohort studied to age 30 years. Self-control during ages 6 to 12 years was measured analogously to that in Moffitt et al., using parent-, teacher-, and self-report methods. Outcome measures to age 30 included criminal offending, substance use, education/employment, sexual behavior, and mental health. Associations between self-control and outcomes were adjusted for possible confounding by gender, socioeconomic status (SES), IQ, and childhood conduct problems (ages 6-10). In confirmation of the findings of Moffitt et al., all outcomes except major depression were significantly (p < .05) associated with childhood self-control. Adjustment for gender, SES, and IQ reduced to some extent the magnitude of the associations. However, adjustment for childhood conduct disorder further reduced the magnitude of many of these associations, with only 4 of the 14 outcomes remaining statistically significantly (p < .05) associated with self-control. After adjustment for gender, SES, IQ, and conduct problems, those individuals who scored higher in self-control had lower odds of violent offending and welfare dependence, were more likely to have obtained a university degree, and had higher income levels. The findings from this study suggest that observed linkages between a measure of childhood self-control and outcomes in adulthood were largely explained by the correlated effects of childhood conduct problems, SES, IQ, and gender. Copyright © 2013 American Academy of Child and Adolescent Psychiatry. Published by Elsevier Inc. All rights reserved.
Rutherford, Adam D.; Munafò, Marcus R.
2016-01-01
There is increasing public and scientific concern regarding the long-term behavioural effects of video game use in children, but currently little consensus as to the nature of any such relationships. We investigated the relationship between video game use in children, degree of violence in games, and measures of depression and a 6-level banded measure of conduct disorder. Data from the Avon Longitudinal Study of Parents and Children were used. A 3-level measure of game use at age 8/9 years was developed, taking into account degree of violence based on game genre. Associations with conduct disorder and depression, measured at age 15, were investigated using ordinal logistic regression, adjusted for a number of potential confounders. Shoot-em-up games were associated with conduct disorder bands, and with a binary measure of conduct disorder, although the strength of evidence for these associations was weak. A sensitivity analysis comparing those who play competitive games to those who play shoot-em-ups found weak evidence supporting the hypothesis that it is violence rather than competitiveness that is associated with conduct disorder. However this analysis was underpowered, and we cannot rule out the possibility that increasing levels of competition in games may be just as likely to account for the observed associations as violent content. Overall game exposure as indicated by number of games in a household was not related to conduct disorder, nor was any association found between shoot-em-up video game use and depression. PMID:26820149
Etchells, Peter J; Gage, Suzanne H; Rutherford, Adam D; Munafò, Marcus R
2016-01-01
There is increasing public and scientific concern regarding the long-term behavioural effects of video game use in children, but currently little consensus as to the nature of any such relationships. We investigated the relationship between video game use in children, degree of violence in games, and measures of depression and a 6-level banded measure of conduct disorder. Data from the Avon Longitudinal Study of Parents and Children were used. A 3-level measure of game use at age 8/9 years was developed, taking into account degree of violence based on game genre. Associations with conduct disorder and depression, measured at age 15, were investigated using ordinal logistic regression, adjusted for a number of potential confounders. Shoot-em-up games were associated with conduct disorder bands, and with a binary measure of conduct disorder, although the strength of evidence for these associations was weak. A sensitivity analysis comparing those who play competitive games to those who play shoot-em-ups found weak evidence supporting the hypothesis that it is violence rather than competitiveness that is associated with conduct disorder. However this analysis was underpowered, and we cannot rule out the possibility that increasing levels of competition in games may be just as likely to account for the observed associations as violent content. Overall game exposure as indicated by number of games in a household was not related to conduct disorder, nor was any association found between shoot-em-up video game use and depression.
Five-year course and outcome of dysthymic disorder: A prospective, naturalistic follow-up study.
Klein, D N; Schwartz, J E; Rose, S; Leader, J B
2000-06-01
There have been few naturalistic follow-up studies of dysthymic disorder. This study describes the 5-year course and outcome of dysthymic disorder. The authors conducted a prospective, longitudinal follow-up study of 86 outpatients with early-onset dysthymic disorder and 39 outpatients with episodic major depressive disorder. Follow-ups, conducted 30 and 60 months after entry into the study, rated patients on the Longitudinal Interval Follow-Up Evaluation and the Modified Hamilton Rating Scale for Depression. The estimated 5-year recovery rate from dysthymic disorder was 52.9%. Among patients who recovered, the estimated risk of relapse was 45.2% during a mean of 23 months of observation. Patients with dysthymic disorder spent approximately 70% of the follow-up period meeting the full criteria for a mood disorder. During the course of the follow-up the patients with dysthymic disorder exhibited significantly greater levels of symptoms and lower functioning and were significantly more likely to attempt suicide and to be hospitalized than were patients with episodic major depressive disorder. Finally, among patients with dysthymic disorder who had never experienced a major depressive episode before entry into the study, the estimated risk of having a first lifetime major depressive episode was 76.9%. Dysthymic disorder is a chronic condition with a protracted course and a high risk of relapse. In addition, almost all patients with dysthymic disorder eventually develop superimposed major depressive episodes. Although patients with dysthymic disorder tend to show mild to moderate symptoms, from a longitudinal perspective, the condition is severe.
What Happens to a Nursing Home Chain When Private Equity Takes Over? A Longitudinal Case Study
Bos, Aline; Harrington, Charlene
2017-01-01
We analyzed what happens to a nursing home chain when private equity takes over, with regard to strategy, financial performance, and resident well-being. We conducted a longitudinal (2000-2012) case study of a large nursing home chain that triangulated qualitative and quantitative data from 5 different data sources. Results show that private equity owners continued and reinforced several strategies that were already put in place before the takeover, including a focus on keeping staffing levels low; the new owners added restructuring, rebranding, and investment strategies such as establishing new companies, where the nursing home chain served as an essential “launch customer.” PMID:29161948
Thompson, Anne; Hollis, Chris; Dagger, David Richards
2003-04-01
This study examines the associations, and possible causal relationship, between mothers' authoritarian attitudes to discipline and child behaviour using cross-sectional and prospective data from a large population sample surveyed in the 1970 British Cohort Study. Results show a clear linear relationship between the degree of maternal approval of authoritarian child-rearing attitudes and the rates of conduct problems at age 5 and age 10. This association is independent of the confounding effects of socio-economic status and maternal psychological distress. Maternal authoritarian attitudes independently predicted the development of conduct problems 5 years later at age 10. The results of this longitudinal study suggest that authoritarian parenting attitudes expressed by mothers may be of significance in the development of conduct problems.
Radially Focused Eddy Current Sensor for Detection of Longitudinal Flaws in Metallic Tubes
NASA Technical Reports Server (NTRS)
Wincheski, Russell A. (Inventor); Simpson, John W. (Inventor); Fulton, James P. (Inventor); Nath, Shridhar C. (Inventor); Todhunter, Ronald G. (Inventor); Namkung, Min (Inventor)
1999-01-01
A radially focused eddy current sensor detects longitudinal flaws in a metal tube. A drive coil induces eddy currents within the wall of the metal tube. A pick-up cod is spaced apart from the drive coil along the length of the metal tube. The pick@up coil is positioned with one end thereof lying adjacent the wall of the metal tube such that the pick-up coil's longitudinal axis is perpendicular to the wall of the metal tube. To isolate the pick-up coil from the magnetic flux of the drive coil and the flux from the induced eddy currents. except the eddy currents diverted by a longitudinal flaw. an electrically conducting material high in magnetic permeability surrounds all of the pick-up coil except its one end that is adjacent the walls of the metal tube. The electrically conducting material can extend into and through the drive coil in a coaxial relationship therewith.
Ward, Marie; McAuliffe, Eilish; Wakai, Abel; Geary, Una; Browne, John; Deasy, Conor; Schull, Michael; Boland, Fiona; McDaid, Fiona; Coughlan, Eoin; O'Sullivan, Ronan
2017-01-23
Early detection of patient deterioration is a key element of patient safety as it allows timely clinical intervention and potential rescue, thus reducing the risks of serious patient safety incidents. Longitudinal patient monitoring systems have been widely recommended for use to detect clinical deterioration. However, there is conflicting evidence on whether they improve patient outcomes. This may in part be related to variation in the rigour with which they are implemented and evaluated. This study aims to evaluate the implementation and effectiveness of a longitudinal patient monitoring system designed for adult patients in the unique environment of the Emergency Department (ED). A novel participatory action research (PAR) approach is taken where socio-technical systems (STS) theory and analysis informs the implementation through the improvement methodology of 'Plan Do Study Act' (PDSA) cycles. We hypothesise that conducting an STS analysis of the ED before beginning the PDSA cycles will provide for a much richer understanding of the current situation and possible challenges to implementing the ED-specific longitudinal patient monitoring system. This methodology will enable both a process and an outcome evaluation of implementing the ED-specific longitudinal patient monitoring system. Process evaluations can help distinguish between interventions that have inherent faults and those that are badly executed. Over 1.2 million patients attend EDs annually in Ireland; the successful implementation of an ED-specific longitudinal patient monitoring system has the potential to affect the care of a significant number of such patients. To the best of our knowledge, this is the first study combining PAR, STS and multiple PDSA cycles to evaluate the implementation of an ED-specific longitudinal patient monitoring system and to determine (through process and outcome evaluation) whether this system can significantly improve patient outcomes by early detection and appropriate intervention for patients at risk of clinical deterioration.
Vallely, Andrew J; MacLaren, David; David, Matthew; Toliman, Pamela; Kelly-Hanku, Angela; Toto, Ben; Tommbe, Rachael; Kombati, Zure; Kaima, Petronia; Browne, Kelwyn; Manineng, Clement; Simeon, Lalen; Ryan, Claire; Wand, Handan; Hill, Peter; Law, Greg; Siba, Peter M; McBride, W John H; Kaldor, John M
2017-01-01
Abstract Introduction: Various forms of penile foreskin cutting are practised in Papua New Guinea. In the context of an ecological association observed between HIV infection and the dorsal longitudinal foreskin cut, we undertook an investigation of this relationship at the individual level. Methods: We conducted a cross-sectional study among men attending voluntary confidential HIV counselling and testing clinics. Following informed consent, participants had a face-to-face interview and an examination to categorize foreskin status. HIV testing was conducted on site and relevant specimens collected for laboratory-based Herpes simplex type-2 (HSV-2), syphilis, Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG), and Trichomonas vaginalis (TV) testing. Results: Overall, 1073 men were enrolled: 646 (60.2%) were uncut; 339 (31.6%) had a full dorsal longitudinal cut; 72 (6.7%) a partial dorsal longitudinal cut; and 14 (1.3%) were circumcised. Overall, the prevalence of HIV was 12.3%; HSV-2, 33.6%; active syphilis, 12.1%; CT, 13.4%; NG, 14.1%; and TV 7.6%. Compared with uncut men, men with a full dorsal longitudinal cut were significantly less likely to have HIV (adjusted odds ratio [adjOR] 0.25, 95%CI: 0.12, 0.51); HSV-2 (adjOR 0.60, 95%CI: 0.41, 0.87); or active syphilis (adjOR 0.55, 95%CI: 0.31, 0.96). This apparent protective effect was restricted to men cut prior to sexual debut. There was no difference between cut and uncut men for CT, NG or TV. Conclusions: In this large cross-sectional study, men with a dorsal longitudinal foreskin cut were significantly less likely to have HIV, HSV-2 and syphilis compared with uncut men, despite still having a complete (albeit morphologically altered) foreskin. The protective effect of the dorsal cut suggests that the mechanism by which male circumcision works is not simply due to the removal of the inner foreskin and its more easily accessible HIV target cells. Exposure of the penile glans and inner foreskin appear to be key mechanisms by which male circumcision confers protection. Further research in this unique setting will help improve our understanding of the fundamental immunohistologic mechanisms by which male circumcision provides protection, and may lead to new biomedical prevention strategies at the mucosal level. PMID:28406272
Vallely, Andrew J; MacLaren, David; David, Matthew; Toliman, Pamela; Kelly-Hanku, Angela; Toto, Ben; Tommbe, Rachael; Kombati, Zure; Kaima, Petronia; Browne, Kelwyn; Manineng, Clement; Simeon, Lalen; Ryan, Claire; Wand, Handan; Hill, Peter; Law, Greg; Siba, Peter M; McBride, W John H; Kaldor, John M
2017-04-03
Various forms of penile foreskin cutting are practised in Papua New Guinea. In the context of an ecological association observed between HIV infection and the dorsal longitudinal foreskin cut, we undertook an investigation of this relationship at the individual level. We conducted a cross-sectional study among men attending voluntary confidential HIV counselling and testing clinics. Following informed consent, participants had a face-to-face interview and an examination to categorize foreskin status. HIV testing was conducted on site and relevant specimens collected for laboratory-based Herpes simplex type-2 (HSV-2), syphilis, Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG), and Trichomonas vaginalis (TV) testing. Overall, 1073 men were enrolled: 646 (60.2%) were uncut; 339 (31.6%) had a full dorsal longitudinal cut; 72 (6.7%) a partial dorsal longitudinal cut; and 14 (1.3%) were circumcised. Overall, the prevalence of HIV was 12.3%; HSV-2, 33.6%; active syphilis, 12.1%; CT, 13.4%; NG, 14.1%; and TV 7.6%. Compared with uncut men, men with a full dorsal longitudinal cut were significantly less likely to have HIV (adjusted odds ratio [adjOR] 0.25, 95%CI: 0.12, 0.51); HSV-2 (adjOR 0.60, 95%CI: 0.41, 0.87); or active syphilis (adjOR 0.55, 95%CI: 0.31, 0.96). This apparent protective effect was restricted to men cut prior to sexual debut. There was no difference between cut and uncut men for CT, NG or TV. In this large cross-sectional study, men with a dorsal longitudinal foreskin cut were significantly less likely to have HIV, HSV-2 and syphilis compared with uncut men, despite still having a complete (albeit morphologically altered) foreskin. The protective effect of the dorsal cut suggests that the mechanism by which male circumcision works is not simply due to the removal of the inner foreskin and its more easily accessible HIV target cells. Exposure of the penile glans and inner foreskin appear to be key mechanisms by which male circumcision confers protection.Further research in this unique setting will help improve our understanding of the fundamental immunohistologic mechanisms by which male circumcision provides protection, and may lead to new biomedical prevention strategies at the mucosal level.
NASA Technical Reports Server (NTRS)
Pal, S.; Kalitan, D.; Woodward, R. D.; Santoro, R. J.
2004-01-01
A uni-element liquid propellant combustion performance and instability study for liquid RP-1 and hot oxygen-rich pre-burner products was conducted, at a chamber pressure of about 1000 psi. using flush and recessed swirl injectors. High-frequency pressure transducer measurements were analyzed to yield the characteristic frequencies which were compared to expected frequencies of the chamber. Modes, which were discovered to be present within the main chamber included, the first longitudinal, detected at approximately 1950 Hz, and the second longitudinal mode at approximately 3800 Hz. An additional first longitudinal quarter wave mode was measured at a frequency of approximately 23000 Hz for the recessed swirl injector configuration. The characteristic instabilities resulting from these experiments were relatively weak averaging 0.2% to 0.3% of the chamber pressure.
The hippocampal longitudinal axis-relevance for underlying tau and TDP-43 pathology.
Lladó, Albert; Tort-Merino, Adrià; Sánchez-Valle, Raquel; Falgàs, Neus; Balasa, Mircea; Bosch, Beatriz; Castellví, Magda; Olives, Jaume; Antonell, Anna; Hornberger, Michael
2018-06-01
Recent studies suggest that hippocampus has different cortical connectivity and functionality along its longitudinal axis. We sought to elucidate the possible different pattern of atrophy in longitudinal axis of hippocampus between Amyloid/Tau pathology and TDP-43-pathies. Seventy-three presenile subjects were included: Amyloid/Tau group (33 Alzheimer's disease with confirmed cerebrospinal fluid [CSF] biomarkers), probable TDP-43 group (7 semantic variant progressive primary aphasia, 5 GRN and 2 C9orf72 mutation carriers) and 26 healthy controls. We conducted a region-of-interest voxel-based morphometry analysis on the hippocampal longitudinal axis, by contrasting the groups, covarying with CSF biomarkers (Aβ 42 , total tau, p-tau) and covarying with episodic memory scores. Amyloid/Tau pathology affected mainly posterior hippocampus while anterior left hippocampus was more atrophied in probable TDP-43-pathies. We also observed a significant correlation of posterior hippocampal atrophy with Alzheimer's disease CSF biomarkers and visual memory scores. Taken together, these data suggest that there is a potential differentiation along the hippocampal longitudinal axis based on the underlying pathology, which could be used as a potential biomarker to identify the underlying pathology in different neurodegenerative diseases. Copyright © 2018 Elsevier Inc. All rights reserved.
ERIC Educational Resources Information Center
Singer, Judith D.; Willett, John B.
The National Center for Education Statistics (NCES) is exploring the possibility of conducting a large-scale multi-year study of teachers' careers. The proposed new study is intended to follow a national probability sample of teachers over an extended period of time. A number of methodological issues need to be addressed before the study can be…
The Lifetime Surveillance of Astronaut Health (LSAH) Project
NASA Technical Reports Server (NTRS)
Bopp, Eugenia; Wear, Mary L.; Lee, Lesley R.; VanBaalen, Mary
2013-01-01
From 1989-2010 NASA conducted a research study, the Longitudinal Study of Astronaut Health, to investigate the incidence of acute and chronic morbidity and mortality in astronauts and to determine whether their occupational exposures were associated with increased risk of death or disability. In 2004, the Institute of Medicine recommended that NASA convert the longitudinal study into an occupational health surveillance program and in 2010, NASA initiated the Lifetime Surveillance of Astronaut Health project. The new program collects data on astronaut workplace exposures, especially those occurring in the training and space flight environments, and conducts operational and health care analyses to look for trends in exposure and health outcomes. Astronaut selection and retention medical standards are rigorous, requiring an extensive clinical testing regimen. As a result, this employee population has contributed to a large set of health data available for analyses. Astronauts represent a special population with occupational exposures not typically experienced by other employee populations. Additionally, astronauts are different from the general population in terms of demographic and physiologic characteristics. The challenges and benefits of conducting health surveillance for an employee population with unique occupational exposures will be discussed. Several occupational surveillance projects currently underway to examine associations between astronaut workplace exposures and medical outcomes will be described.
A comparison of multiple imputation methods for incomplete longitudinal binary data.
Yamaguchi, Yusuke; Misumi, Toshihiro; Maruo, Kazushi
2018-01-01
Longitudinal binary data are commonly encountered in clinical trials. Multiple imputation is an approach for getting a valid estimation of treatment effects under an assumption of missing at random mechanism. Although there are a variety of multiple imputation methods for the longitudinal binary data, a limited number of researches have reported on relative performances of the methods. Moreover, when focusing on the treatment effect throughout a period that has often been used in clinical evaluations of specific disease areas, no definite investigations comparing the methods have been available. We conducted an extensive simulation study to examine comparative performances of six multiple imputation methods available in the SAS MI procedure for longitudinal binary data, where two endpoints of responder rates at a specified time point and throughout a period were assessed. The simulation study suggested that results from naive approaches of a single imputation with non-responders and a complete case analysis could be very sensitive against missing data. The multiple imputation methods using a monotone method and a full conditional specification with a logistic regression imputation model were recommended for obtaining unbiased and robust estimations of the treatment effect. The methods were illustrated with data from a mental health research.
Need-Supportive Advising for Undecided Students
ERIC Educational Resources Information Center
Leach, Jennifer Kay; Patall, Erika A.
2016-01-01
To explore the relationship between need-supportive advising and students' decision making on academic majors, we conducted a longitudinal study of 145 students based on their reports of basic psychological need satisfaction and their decision-making processes. We hypothesized that need-supportive advising would positively contribute to autonomous…
Confident in Their College Prep
ERIC Educational Resources Information Center
Torres, Amanda
2016-01-01
Every year, the Higher Education Research Institute (HERI) at UCLA conducts The Freshman Survey, a national longitudinal study that covers a wide range of student characteristics--from secondary school achievement and activities to educational and career plans to values, attitudes, beliefs, and self concept. To identify the academic and personal…
ERIC Educational Resources Information Center
Wallhagen, Margaret I.
2010-01-01
Purpose: To explore dimensions of stigma experienced by older adults with hearing loss and those with whom they frequently communicate to target interventions promoting engagement and positive aging. Design and Methods: This longitudinal qualitative study conducted interviews over 1 year with dyads where one partner had hearing loss. Participants…
The Development of Detour Ability during Infancy.
ERIC Educational Resources Information Center
Lockman, Jeffrey J.
1984-01-01
Three longitudinal studies were conducted to examine the generalization of detour ability across motor responses and barrier types, and to investigate the relationship between the development of object permanence and detour ability. Results were discussed in terms of differences in reaching and locomotor detour performances. (Author/CI)
Perceptions and Positionings of Colleges in New York City: A Longitudinal Study of Brand Images
ERIC Educational Resources Information Center
Clark, Sylvia D.
2005-01-01
A study of high school seniors' perceptions of colleges, conducted in 1979, was replicated 23 years later. The study affords an opportunity to examine perceptual changes over time and provides an additional perspective on the positioning of colleges, apart from other well-known surveys. This information may be useful for those involved in…
ERIC Educational Resources Information Center
Fung, Dennis; Howe, Christine
2014-01-01
This article reports the findings of a one-year longitudinal study that investigated the impact of group work on the development of students' critical thinking in Hong Kong secondary schools. It explores whether the participation of teachers in a group-based teaching intervention adapted from an earlier study conducted in the United Kingdom (UK)…
ERIC Educational Resources Information Center
Rienties, Bart; Luchoomun, Dharma; Tempelaar, Dirk
2014-01-01
In Europe there is a growing concern among educators and policy makers that students are not well-prepared to start a Master programme. This study draws on longitudinal research conducted at four universities in the Netherlands and a follow-up exploratory purposively chosen from one of the study sites. In Study 1, differences in academic…
Very Early Predictors of Conduct Problems and Crime: Results from a National Cohort Study
ERIC Educational Resources Information Center
Murray, Joseph; Irving, Barrie; Farrington, David P.; Colman, Ian; Bloxsom, Claire A. J.
2010-01-01
Background: Longitudinal research has produced a wealth of knowledge about individual, family, and social predictors of crime. However, nearly all studies have started after children are age 5, and little is known about earlier risk factors. Methods: The 1970 British Cohort Study is a prospective population survey of more than 16,000 children born…
ERIC Educational Resources Information Center
Toby, Megan; Jaciw, Andrew; Ma, Boya; Lipton, Akiko
2011-01-01
PCI Education conducted a three-year longitudinal study to determine the comparative effectiveness of the "PCI Reading Program" ("PCI") for students with severe disabilities as implemented in Florida's Brevard Public Schools and Miami-Dade County Public Schools. The primary question addressed by the study is whether students…
Efficiency Study of NLS Base-Year Design. RTI-22U-884-3.
ERIC Educational Resources Information Center
Moore, R. P.; And Others
An efficiency study was conducted of the base year design used for the National Longitudinal Study of the High School Class of 1972 (NLS). Finding the optimal design involved a search for the numbers of sample schools and students that would maximize the variance at a given cost. Twenty-one variables describing students' plans, attitudes,…
ERIC Educational Resources Information Center
Elpus, Kenneth
2013-01-01
This study examined the college entrance examination scores of music and non-music students in the United States, drawing data from the restricted-use data set of the Education Longitudinal Study of 2002 (ELS), a nationally representative education study ("N" = 15,630) conducted by the National Center for Education Statistics. Analyses…
Nonmedical Drug Use among University Students -- 1967-1970.
ERIC Educational Resources Information Center
Dvorak, Edward J.; Rupprecht, Paul
This report is a summary of a longitudinal study of nonmedical drug use among university students which was carried out by members of the staff of the University of Minnesota Health Service. The study was conducted in 2 phases. The subjects in the first phase of the study were students who registered for the first time at the University of…
ERIC Educational Resources Information Center
Wolfe, Richard G.
The Second International Mathematics Study (SIMS) of the International Association for the Evaluation of Educational Achievement (IEA) was conducted in 20 countries on two sampled populations: Population A of 13-year-olds and Population B of students studying mathematics in their final year of secondary school. Mathematics achievement was measured…
George, Emma S.; Feng, Xiaoqi; Merom, Dafna; Bennie, Andrew; Cook, Amelia; Dwyer, Genevieve; Pang, Bonnie; Astell-Burt, Thomas
2018-01-01
Physical activity and diet are major modifiable risk factors for chronic disease and have been shown to be associated with neighborhood built environment. Systematic review evidence from longitudinal studies on the impact of changing the built environment on physical activity and diet is currently lacking. A systematic review of natural experiments of neighborhood built environment was conducted. The aims of this systematic review were to summarize study characteristics, study quality, and impact of changes in neighborhood built environment on physical activity and diet outcomes among residents. Natural experiments of neighborhood built environment change, exploring longitudinal impacts on physical activity and/or diet in residents, were included. From five electronic databases, 2084 references were identified. A narrative synthesis was conducted, considering results in relation to study quality. Nineteen papers, reporting on 15 different exposures met inclusion criteria. Four studies included a comparison group and 11 were pre-post/longitudinal studies without a comparison group. Studies reported on the impact of redeveloping or introducing cycle and/or walking trails (n = 5), rail stops/lines (n = 4), supermarkets and farmers’ markets (n = 4) and park and green space (n = 2). Eight/15 studies reported at least one beneficial change in physical activity, diet or another associated health outcome. Due to limitations in study design and reporting, as well as the wide array of outcome measures reported, drawing conclusions to inform policy was challenging. Future research should consider a consistent approach to measure the same outcomes (e.g., using measurement methods that collect comparable physical activity and diet outcome data), to allow for pooled analyses. Additionally, including comparison groups wherever possible and ensuring high quality reporting is essential. PMID:29373567
MacMillan, Freya; George, Emma S; Feng, Xiaoqi; Merom, Dafna; Bennie, Andrew; Cook, Amelia; Sanders, Taren; Dwyer, Genevieve; Pang, Bonnie; Guagliano, Justin M; Kolt, Gregory S; Astell-Burt, Thomas
2018-01-26
Physical activity and diet are major modifiable risk factors for chronic disease and have been shown to be associated with neighborhood built environment. Systematic review evidence from longitudinal studies on the impact of changing the built environment on physical activity and diet is currently lacking. A systematic review of natural experiments of neighborhood built environment was conducted. The aims of this systematic review were to summarize study characteristics, study quality, and impact of changes in neighborhood built environment on physical activity and diet outcomes among residents. Natural experiments of neighborhood built environment change, exploring longitudinal impacts on physical activity and/or diet in residents, were included. From five electronic databases, 2084 references were identified. A narrative synthesis was conducted, considering results in relation to study quality. Nineteen papers, reporting on 15 different exposures met inclusion criteria. Four studies included a comparison group and 11 were pre-post/longitudinal studies without a comparison group. Studies reported on the impact of redeveloping or introducing cycle and/or walking trails ( n = 5), rail stops/lines ( n = 4), supermarkets and farmers' markets ( n = 4) and park and green space ( n = 2). Eight/15 studies reported at least one beneficial change in physical activity, diet or another associated health outcome. Due to limitations in study design and reporting, as well as the wide array of outcome measures reported, drawing conclusions to inform policy was challenging. Future research should consider a consistent approach to measure the same outcomes (e.g., using measurement methods that collect comparable physical activity and diet outcome data), to allow for pooled analyses. Additionally, including comparison groups wherever possible and ensuring high quality reporting is essential.
Sudell, Maria; Kolamunnage-Dona, Ruwanthi; Tudur-Smith, Catrin
2016-12-05
Joint models for longitudinal and time-to-event data are commonly used to simultaneously analyse correlated data in single study cases. Synthesis of evidence from multiple studies using meta-analysis is a natural next step but its feasibility depends heavily on the standard of reporting of joint models in the medical literature. During this review we aim to assess the current standard of reporting of joint models applied in the literature, and to determine whether current reporting standards would allow or hinder future aggregate data meta-analyses of model results. We undertook a literature review of non-methodological studies that involved joint modelling of longitudinal and time-to-event medical data. Study characteristics were extracted and an assessment of whether separate meta-analyses for longitudinal, time-to-event and association parameters were possible was made. The 65 studies identified used a wide range of joint modelling methods in a selection of software. Identified studies concerned a variety of disease areas. The majority of studies reported adequate information to conduct a meta-analysis (67.7% for longitudinal parameter aggregate data meta-analysis, 69.2% for time-to-event parameter aggregate data meta-analysis, 76.9% for association parameter aggregate data meta-analysis). In some cases model structure was difficult to ascertain from the published reports. Whilst extraction of sufficient information to permit meta-analyses was possible in a majority of cases, the standard of reporting of joint models should be maintained and improved. Recommendations for future practice include clear statement of model structure, of values of estimated parameters, of software used and of statistical methods applied.
Assessing corporate project impacts in changeable contexts: A human rights perspective
DOE Office of Scientific and Technical Information (OSTI.GOV)
Salcito, Kendyl, E-mail: kendyl.salcito@unibas.ch; University of Basel, P.O. Box, CH-4003 Basel; NomoGaia, 1900 Wazee Street, Suite 303, Denver, CO 80202
Project-level impact assessment was originally conceived as a snapshot taken in advance of project implementation, contrasting current conditions with a likely future scenario involving a variety of predicted impacts. Current best practice guidance has encouraged a shift towards longitudinal assessments from the pre-project stage through the implementation and operating phases. Experience and study show, however, that assessment of infrastructure-intensive projects rarely endures past the project's construction phase. Negative consequences for environmental, social and health outcomes have been documented. Such consequences clarify the pressing need for longitudinal assessment in each of these domains, with human rights impact assessment (HRIA) as anmore » umbrella over, and critical augmentation of, environmental, social and health assessments. Project impacts on human rights are more closely linked to political, economic and other factors beyond immediate effects of a company's policy and action throughout the project lifecycle. Delineating these processes requires an adequate framework, with strategies for collecting longitudinal data, protocols that provide core information for impact assessment and guidance for adaptive mitigation strategies as project-related effects change over time. This article presents general principles for the design and implementation of sustained, longitudinal HRIA, based on experience assessing and responding to human rights impact in a uranium mining project in Malawi. The case study demonstrates the value of longitudinal assessment both for limiting corporate risk and improving human welfare. - Graphical abstract: Assessing changes in human rights condition as affected by both project and context, over time. - Highlights: • Corporate capital projects affect human rights in myriad ways. • Ongoing, longitudinal impact assessment techniques are needed. • We present an approach for conducting longitudinal human rights impact assessment. • Our methodology allows distinguishing corporate impacts from contextual changes. • Promptly observing context changes and impacts enables companies to react nimbly.« less
DOT National Transportation Integrated Search
1999-06-01
This report contains the description and test results of overhead stowage bin calibrations and longitudinal impact testing of a 10-foot transport airframe section conducted at the Transportation Research Center Inc. (TRC). The purpose of the tests wa...
How do Rumination and Social Problem Solving Intensify Depression? A Longitudinal Study.
Hasegawa, Akira; Kunisato, Yoshihiko; Morimoto, Hiroshi; Nishimura, Haruki; Matsuda, Yuko
2018-01-01
In order to examine how rumination and social problem solving intensify depression, the present study investigated longitudinal associations among each dimension of rumination and social problem solving and evaluated aspects of these constructs that predicted subsequent depression. A three-wave longitudinal study, with an interval of 4 weeks between waves, was conducted. Japanese university students completed the Beck Depression Inventory-Second Edition, Ruminative Responses Scale, Social Problem-Solving Inventory-Revised Short Version, and Interpersonal Stress Event Scale on three occasions 4 weeks apart ( n = 284 at Time 1, 198 at Time 2, 165 at Time 3). Linear mixed models were analyzed to test whether each variable predicted subsequent depression, rumination, and each dimension of social problem solving. Rumination and negative problem orientation demonstrated a mutually enhancing relationship. Because these two variables were not associated with interpersonal conflict during the subsequent 4 weeks, rumination and negative problem orientation appear to strengthen each other without environmental change. Rumination and impulsivity/carelessness style were associated with subsequent depressive symptoms, after controlling for the effect of initial depression. Because rumination and impulsivity/carelessness style were not concurrently and longitudinally associated with each other, rumination and impulsive/careless problem solving style appear to be independent processes that serve to intensify depression.
NASA Astrophysics Data System (ADS)
Kolesnikov, D. V.; Ivanchenko, G. S.; Lebedev, N. G.
2016-06-01
A method of surface curvature of carbon nanotubes has been proposed for quantitative estimation of the longitudinal conductivity of nanotubes. A dispersion relation for the electron spectrum of single-walled carbon nanotubes has been obtained analytically. The change in the zone structure of nanotubes of various types and diameters caused by taking into account the surface curvature has been analyzed. The temperature dependence of the longitudinal component of conductivity with allowance for the surface curvature for a series of nanotubes has been calculated. The comparison with the conductivity of a plane graphene has been performed. It has been shown that, in zig-zag tubes, the correction of the conductivity for the surface curvature decreases with an increase in temperature as well as with an increase in the radius of curvature.
Intimate Partner Violence, Maternal Gatekeeping, and Child Conduct Problems
Zvara, Bharathi J.; Mills-Koonce, W. Roger; Cox, Martha
2017-01-01
We examined the mediating role of parenting behavior on the relationship between intimate partner violence and child conduct problems, as well as the moderating role of maternal gatekeeping to these associations. The sample (N = 395) is from a longitudinal study of rural poverty in the eastern United States, exploring the ways in which child, family, and contextual factors shape child development over time. Study findings indicate that a father’s harsh–intrusive parenting behavior may be a key mediating pathway linking intimate partner violence and child conduct problems. Study findings further provide evidence for problematic outcomes for children when mothers encourage fathers with high levels of harsh–intrusive parenting to interact with their children. PMID:28943690
ERIC Educational Resources Information Center
Murray, Christopher; Doren, Bonnie; Gau, Jeff M.; Zvoch, Keith; Seeley, John R.
2015-01-01
The purpose of the current study was to develop a multi-indicator construct of economic hardship among adolescents with disabilities (N = 9,230) participating in the National Longitudinal Transition Study-2, the largest, most comprehensive investigation of adolescents with disabilities ever conducted. Five theoretically relevant indicators (i.e.,…
ERIC Educational Resources Information Center
Rigles, Bethany; Ipsen, Catherine; Arnold, Nancy; Seekins, Tom
2011-01-01
Vocational rehabilitation (VR) clients who leave the system prematurely experience worse employment outcomes than clients who stay in services. The authors conducted this study to learn about factors leading to premature exit by rural VR clients. Results will inform survey development for a large longitudinal study on this topic. The authors…
ERIC Educational Resources Information Center
Granville, Arthur C.; Love, John M.
This brief report summarizes the analysis and conclusions presented in detail in Interim Report VI regarding the feasibility of conducting a longitudinal study of Project Developmental Continuity (PDC). This project is a Head Start demonstration program aimed at providing educational and developmental continuity between children's Head Start and…
Need for Recovery, Home-Work Interference and Performance: Is Lack of Concentration the Link?
ERIC Educational Resources Information Center
Demerouti, Evangelia; Taris, Toon W.; Bakker, Arnold B.
2007-01-01
This study examines the mechanisms through which experiences in the home domain influence work performance by bringing together the literature on recovery and the work-family interface. A longitudinal study among 123 employees from different organizations was conducted to investigate whether need for recovery and home-work interference (HWI)…
ERIC Educational Resources Information Center
Tseng, Wen-Chih
2017-01-01
The effectiveness of an intervention using LEGO® SERIOUS PLAY® (LSP), a reflective tool using LEGO® building bricks, to speed the development of narrative identity in economically disadvantaged college students was studied. A longitudinal experimental study with non equivalent experimental/control groups (N = 45) was conducted to examine whether…
Adult Careers: Does Childhood IQ Predict Later Life Outcome?
ERIC Educational Resources Information Center
Firkowska-Mankiewicz, Anna
2011-01-01
The author's plenary address at the 3rd International Association for the Scientific Study of Intellectual Disabilities-Europe Conference in Rome, Italy (October 2010), provided a retrospective overview of a longitudinal study conducted with a cohort of pre-teens (11 and 13 years of age) residing in Warsaw, Poland, in the 1970s. The intent was to…
ERIC Educational Resources Information Center
Murphy, Megan J.; Mermelstein, Liza C.; Edwards, Katie M.; Gidycz, Christine A.
2012-01-01
Objective: This article examines the relationship between dispositional mindfulness, health behaviors (e.g., sleep, eating, and exercise), and physical health. Participants: Participants included 441 college women. Methods: Women completed self-report surveys at the beginning and end of a 10-week academic quarter. The study was conducted over 5…
The Impact of TCARE[R] on Service Recommendation, Use, and Caregiver Well-Being
ERIC Educational Resources Information Center
Kwak, Jung; Montgomery, Rhonda J. V.; Kosloski, Karl; Lang, Josh
2011-01-01
Purpose of the Study: Findings are reported from a study that examined the effects of the Tailored Caregiver Assessment and Referral (TCARE[R]) protocol, a care management process designed to help family caregivers, on care planning and caregiver outcomes. Design and Methods: A longitudinal, randomized controlled trial was conducted with 97…
ERIC Educational Resources Information Center
Zelkowski, Jeremy
2011-01-01
This study was conducted to discover and examine school-level characteristics that can affect change in high school graduates from being college-eligible to college-ready. Using the National Educational Longitudinal Study (NELS:88), the article describes and interprets the results. Findings indicate school personnel (principals, teachers,…
Prospective Use of Psychosocial Factors to Predict Cigarette Smoking in Adolescents.
ERIC Educational Resources Information Center
Rauch, Jill Mestel; And Others
In order to prevent cigarette smoking in young adolescents, the factors which cause it need to be better understood. A study was conducted to investigate the contribution of three psychosocial factors, suggested by previous theory and research, on smoking in a longitudinal sample of seventh graders (N=3,940) who were studied again in the eighth…
An Examination of Research Collaboration in Psychometrics Utilizing Social Network Analysis Methods
ERIC Educational Resources Information Center
DiCrecchio, Nicole C.
2016-01-01
Co-authorship networks have been studied in many fields as a way to understand collaboration patterns. However, a comprehensive exploration of the psychometrics field has not been conducted. Also, few studies on co-author networks have included longitudinal analyses as well as data on the characteristics of authors in the network. Including both…
Exploring Long-Term Productive Vocabulary Development in an EFL Context: The Role of Motivation
ERIC Educational Resources Information Center
Zheng, Yongyan
2012-01-01
The paper reports on a longitudinal multiple-case study that probed into four advanced university-level Chinese EFL learners' situated vocabulary learning experiences and explored the role of L2 motivation in their productive vocabulary development. In the study, Lexical Frequency Profile analysis and semi-structured interviews were conducted with…
A STUDY OF COGNITIVE DEVELOPMENT AND PERFORMANCE IN CHILDREN WITH NORMAL AND DEFECTIVE HEARING.
ERIC Educational Resources Information Center
TEMPLIN, MILDRED C.
A COMPARATIVE, LONGITUDINAL STUDY WAS CONDUCTED TO EXAMINE SPECIFIC PERFORMANCE CHARACTERISTICS OF DEAF AND NORMAL CHILDREN ON SELECTED COGNITIVE TASKS. THE SAMPLE, DISTRIBUTED INTO 3 AGE CATEGORIES, CONSISTED OF 72 NORMAL AND 60 DEAF CHILDREN. MEASURES WERE SELECTED TO ASSESS THE PERFORMANCE OF SUBJECTS (1) IN DIFFERENT AREAS OF COGNITION, (2) BY…
The Health of Caregiving Grandmothers: A Rural-Urban Comparison
ERIC Educational Resources Information Center
Bigbee, Jeri L.; Musil, Carol; Kenski, Diane
2011-01-01
Purpose: The purpose of this study was to compare the characteristics of rural versus urban caregiving grandmothers along with their physical and mental health status. Methods: A secondary analysis of data produced from the first wave of a longitudinal study of 485 Ohio grandmothers was conducted. Health status was measured using the SF-36 Health…
The Association between Changes in Health Status and Nursing Home Resident Quality of Life
ERIC Educational Resources Information Center
Degenholtz, Howard B.; Rosen, Jules; Castle, Nicholas; Mittal, Vikas; Liu, Darren
2008-01-01
Purpose: Previous research on nursing home resident quality of life (QOL) has mainly been cross-sectional. This study examined the association between changes in QOL and changes in resident clinical factors. Design and Methods: A longitudinal study of resident QOL was conducted in two nursing homes. Self-report interviews using a multidimensional…
Adolescent Alcohol Use Self-Report Stability: A Decade of Panel Study Data
ERIC Educational Resources Information Center
Shillington, Audrey M.; Clapp, John D.; Reed, Mark B.; Woodruff, Susan I.
2011-01-01
This study analyzed six waves of panel data from the National Longitudinal Survey of Youth (NLSY). These analyses were conducted to test the stability of self-reported lifetime use and age of onset. Intraclass correlation coefficients (ICCs) indicated that the stability of age of onset reports decreased with longer time frames between follow-ups.…
ERIC Educational Resources Information Center
Antshel, Kevin M.; Faraone, Stephen V.; Maglione, Katherine; Doyle, Alysa; Fried, Ronna; Seidman, Larry; Biederman, Joseph
2008-01-01
A study was conducted to establish the relationship between Attention-Deficit/Hyperactivity (ADHD) disorder and high-IQ children and whether ADHD has a high predictive value among youths with high-IQ. Results further supported the hypothesis for the predictive validity of ADHD in high-IQ youths.
Sun Protection during Snow Sports: An Analysis of Behavior and Psychosocial Determinants
ERIC Educational Resources Information Center
Janssen, Eva; van Kann, Dave; de Vries, Hein; Lechner, Lilian; van Osch, Liesbeth
2015-01-01
This study investigated sun protective behavior during snow sports and its psychosocial determinants. A longitudinal study was conducted among 418 Dutch adults who planned to go on a ski holiday. Participants were asked to fill in a questionnaire before and after their ski trip. In the baseline questionnaire several psychosocial factors were…
Fantasy-Reality Use of Mass Media by Children: A Longitudinal Study.
ERIC Educational Resources Information Center
Smith, David M.
1981-01-01
A study of media use by children was conducted to produce an index of fantasy-reality orientation derived from the respondents' stated preferences for media content combined with their responses to a series of open-ended questions designed to tap the gratifications they claimed to receive from the media. Data were collected in three waves, when…
Factors Related to White, Black, and Hispanic Women's Mathematics Attainments: A Descriptive Study.
ERIC Educational Resources Information Center
Rothschild, Susan J. S.; Lichtman, Marilyn
Virtually no research conducted on women and mathematics is longitudinal in scope, generalizable in extent, and ethnic-race specific in nature. This descriptive study begins to fill the gap by examining the effects of background, school, and social-psychological factors on Hispanic, black, and white women's mathematics attainments. Data for the…
ERIC Educational Resources Information Center
Goosen, Richard F.
2009-01-01
This study provides information for higher education leaders that have or are considering conducting Computer Aided Design (CAD) instruction using student owned notebook computers. Survey data were collected during the first 8 years of a pilot program requiring engineering technology students at a four year public university to acquire a notebook…
Benzerroug, E. H.; Janssens, P. G.; Ambroise-Thomas, P.
1991-01-01
On the basis of geoclimatic characteristics, the Saharan region of Algeria (area, 2 million km2) is made up of several subregions; analysis of the historical data on malaria in this region seems to show that the epidemiological situation is closely linked to climatic and hydrographic conditions. A longitudinal sero-epidemiological study was conducted in this vast region from September 1983 to April 1985. The general findings do not appear to support the existence of active foci of transmission, but analysis of the data for certain oases and localities leads to a quite different assessment of the epidemiological situation. At Ouargla, for example, the serological results obtained by indirect immunofluorescence show prevalence of under 5% in the four successive surveys, whereas in Heïha oasis over 50% of subjects over 30 years of age were found to be seropositive. The results of the longitudinal seroepidemiological surveys conducted in a number of localities and oases in the Saharan region reflect the diversity of epidemiological settings and provide evidence that there is low-level malaria transmission in some oases such as Heïha, Yakou, Ihérir and probably in In-Salah. These surveys confirm that malaria transmission has been halted in the former foci such as Ouargla and Timimoune. Finally, the longitudinal sero-epidemiological study shows there are movements of potential parasite carriers from countries south of the Sahara and therefore that oases associated with trans-Saharan trade are vulnerable. PMID:1786620
Page, Andrew
2016-01-01
Purpose This study assessed the long-term stability and instability of subjective well-being during post-school transition (i.e., transition from adolescence to young adulthood) and evaluated the determinants of transition stability. Methods Using two cohorts from a national representative longitudinal study, the Longitudinal Study of Australian Youth (N = 20991), latent profile analysis and latent transition analysis were conducted to examine transition patterns among subjective well-being profiles for youth from age 17 to 25. Multinomial logistic regressions were conducted to evaluate whether key socio-demographic variables were associated with transition stability. Results We identified: (1) three subjective well-being profiles: Low (30%), Moderate (50%), and High (20%); and (2) three major transition patterns among these subjective well-being profiles: stable, partially-stable, and unstable. The majority of youth had stable transition patterns during the transition from adolescence to adulthood. A large percentage of youth (52%) started low in subjective well-being profile and remained in the low subjective-wellbeing profile. Our examination also revealed gender was the most pronounced indicator for transition stability during this time period, with males more likely to have unstable transition patterns than females. Conclusions Results suggest that different subjective well-being status and transition patterns can be identified in the post-high school transition to adulthood, including unstable transitions. By targeting those groups more vulnerable to transition, mental health promotion and interventions may be delivered more effectively. PMID:27232183
[Healthcare services research on pain in Germany. A survey].
Häuser, W; Neugebauer, E; Petzke, F
2015-10-01
Within the last ten years healthcare services research has developed into an independent interdisciplinary field of research. A selective search of the literature was conducted in the database Google Scholar and the database on healthcare services research in Germany (http://versorgungsforschung-deutschland.de) for healthcare services research projects on pain in Germany. Healthcare services research projects were conducted by pharmaceutical companies, patient self-help organizations, scientific societies, statutory health insurance companies and university departments on acute and chronic pain. Valid data on the epidemiology, grading and treatment of chronic pain are available. There was an overuse of opioids and invasive procedures in patients with chronic low back pain, fibromyalgia syndrome and somatoform pain disorders. Databases for patients with chronic pain are currently constructed by pain societies. The fragmentation of data from health insurance companies, old age pension insurances, clinical institutions and population surveys and inconsistencies in diagnosing or encoding chronic pain impede the carrying out of significant longitudinal studies. Based on the data available, the needs of care for patients with chronic pain and the necessary care services cannot be derived. Important topics of future healthcare services research on pain are longitudinal studies on the cost efficacy and risks of inpatient and outpatient pain therapy based on routine data of health insurance companies, old age pension insurances and pain registries, longitudinal studies on "patient careers" (i.e. sequences of healthcare) and the identification of potential starting points for control of healthcare.
McAdams, T A; Rijsdijk, F V; Neiderhiser, J M; Narusyte, J; Shaw, D S; Natsuaki, M N; Spotts, E L; Ganiban, J M; Reiss, David; Leve, L D; Lichtenstein, P; Eley, T C
2015-01-01
Parental depressive symptoms are associated with emotional and behavioural problems in offspring. However, genetically informative studies are needed to distinguish potential causal effects from genetic confounds, and longitudinal studies are required to distinguish parent-to-child effects from child-to-parent effects. We conducted cross-sectional analyses on a sample of Swedish twins and their adolescent offspring (n = 876 twin families), and longitudinal analyses on a US sample of children adopted at birth, their adoptive parents, and their birth mothers (n = 361 adoptive families). Depressive symptoms were measured in parents, and externalizing and internalizing problems measured in offspring. Structural equation models were fitted to the data. Results of model fitting suggest that associations between parental depressive symptoms and offspring internalizing and externalizing problems remain after accounting for genes shared between parent and child. Genetic transmission was not evident in the twin study but was evident in the adoption study. In the longitudinal adoption study child-to-parent effects were evident. We interpret the results as demonstrating that associations between parental depressive symptoms and offspring emotional and behavioural problems are not solely attributable to shared genes, and that bidirectional effects may be present in intergenerational associations.
Functional recovery following critical illness in children: the "wee-cover" pilot study.
Choong, Karen; Al-Harbi, Samah; Siu, Katie; Wong, Katie; Cheng, Ji; Baird, Burke; Pogorzelski, David; Timmons, Brian; Gorter, Jan-Willem; Thabane, Lehana; Khetani, Mary
2015-05-01
To determine the feasibility of conducting a longitudinal prospective study to evaluate functional recovery and predictors of impaired functional recovery in critically ill children. Prospective pilot study. Single-center PICU at McMaster Children's Hospital, Hamilton, Canada. Children aged 12 months to 17 years, with at least one organ dysfunction, limited mobility or bed rest during the first 48 hours of PICU admission, and a minimum 48-hour PICU length of stay, were eligible. Patients transferred from a neonatal ICU prior to ever being discharged home, already mobilizing well or at baseline functional status at time of screening, with an English language barrier, and prior enrollment into this study, were excluded. None. The primary outcome was feasibility, as defined by the ability to screen, enroll eligible patients, and execute the study procedures and measurements on participants. Secondary outcomes included functional status at baseline, 3 and 6 months, PICU morbidity, and mortality. Functional status was measured using the Pediatric Evaluation of Disability Inventory and the Participation and Environment Measure for Children and Youth. Thirty-three patients were enrolled between October 2012 and April 2013. Consent rate was 85%, and follow-up rates were 93% at 3 months and 71% at 6 months. We were able to execute the study procedures and measurements, demonstrating feasibility of conducting a future longitudinal study. Functional status deteriorated following critical illness. Recovery appears to be influenced by baseline health or functional status and severity of illness. Longitudinal research is needed to understand how children recover after a critical illness. Our results suggest factors that may influence the recovery trajectory and were used to inform the methodology, outcomes of interest, and appropriate sample size of a larger multicenter study evaluating functional recovery in this population.
Barker, Edward D; Oliver, Bonamy R; Maughan, Barbara
2010-11-01
It is increasingly recognized that youth who follow early onset persistent (EOP), childhood limited (CL) and adolescent onset (AO) trajectories of conduct problems show somewhat varying patterns of risk (in childhood) and adjustment problems (in adolescence and adulthood). Little, however, is known about how other adjustment problems differentially co-develop with the EOP, CL and AO trajectories across the childhood and adolescent years. Using data from the Avon Longitudinal Study of Parents and Children, an epidemiological, longitudinal cohort of boys and girls, we estimated growth curves for parent-reported hyperactivity, emotional difficulties, peer relational problems, and prosocial behaviors conditional on trajectories of conduct problems (i.e., EOP, CL and AO) from ages 4 to 13 years. At ages 7-8 years, DSM-IV-based diagnoses of conduct disorder, oppositional-defiant disorder, attention deficit/hyperactivity disorder (ADHD), anxiety, depression were examined by conduct problems trajectory. Overall, the development of hyperactivity, emotional difficulties, peer relational problems, and prosocial behaviors mirrored the development of conduct problems, showing similar trajectories. Results indicated that the problems of EOP youth were persistent across domains, CL youth showed decreased behavior problems while increasing in prosocial behaviors, and AO youth increased in adjustment problems after 10 years of age. © 2010 The Authors. Journal of Child Psychology and Psychiatry © 2010 Association for Child and Adolescent Mental Health.
Conducting Three-Level Longitudinal Analyses
ERIC Educational Resources Information Center
Peugh, James L.; Heck, Ronald H.
2017-01-01
Researchers in the field of early adolescence interested in quantifying the environmental influences on a response variable of interest over time would use cluster sampling (i.e., obtaining repeated measures from students nested within classrooms and/or schools) to obtain the needed sample size. The resulting longitudinal data would be nested at…
The Merits of Using Longitudinal Mediation
ERIC Educational Resources Information Center
Jose, Paul E.
2016-01-01
Many of the mediation analyses reported in the literature are based on concurrent or single-occasion data sets. The 2 overarching themes of the present article are: Results of concurrent mediations are inherently ambiguous, and researchers would be wise to conduct mediations on longitudinal data sets instead. An example included here demonstrates…
Parikh, Punam P; Rubio, Gustavo A; Patel, Kunal; Gupta, Kapil; Jones, Keith; Rey, Jorge; Robinson, Handel
2018-02-01
This study evaluates differences in wound complication rate when transverse versus longitudinal incision is utilized to expose femoral vessels in managing patients with peripheral vascular disease. A retrospective review from 2013 to 2015 was conducted of 150 patients undergoing 156 lower extremity revascularizations with femoral artery exposure through a groin incision. Patients were stratified into 2 groups, transverse versus longitudinal groin incision. Data were reviewed for 3 surgeons that utilize either transverse or longitudinal groin incision in patients undergoing common or iliofemoral endarterectomies, or where femoral artery was used as inflow and/or outflow vessel for limb revascularization. Each group had a comparative outcomes analysis based on incision type. The primary outcome was wound complication, defined as any wound infection, lymphocele, hematoma, dehiscence, pseudoaneurysm, or necrosis. Other outcomes studied included unplanned return to operating room for wound complication, wound vacuum therapy, and soft-tissue flap closure. Data were analyzed using 2-tailed chi-squared test and Student's t-test. Patients in the transverse (n = 85 cases) versus longitudinal (n = 71 cases) cohorts were similar in relation to demographics and comorbidities. Overall mean follow-up was 220 days. Patients with a transverse as compared to longitudinal incision had a significantly lower overall wound complication rate, 7% vs. 42%, respectively (P < 0.001). Furthermore, transverse incisions were associated with lower incidence of unplanned return to the operating room to manage wound complications than patients with a longitudinal incision (5% vs. 23%, respectively; P < 0.001). Transverse versus longitudinal incisions were also associated with significantly lower need for wound vacuum therapy (6% vs. 15%, respectively; P < 0.05) and muscle flap closure (0% vs. 13%, respectively; P < 0.001) for wound complications. Transverse groin incisions for femoral artery exposure may offer a lower risk of wound complications for open procedures as compared to a longitudinal incision. While longitudinal incisions may have higher wound complication rates, incisional approach is contingent on anatomical circumstance and treated disease pattern. Patients should undergo appropriate preoperative counseling regarding wound healing in preparation for limb revascularization. Copyright © 2017 Elsevier Inc. All rights reserved.
Curriculum Challenges in California.
ERIC Educational Resources Information Center
Adler, Louise
1993-01-01
This paper presents findings from a longitudinal study that examined the extent and types of challenges to curriculum in California school districts. A survey of school districts conducted in 1990 yielded 421 usable responses. The second survey, sent in 1991, elicited 379 responses, a 37.5 percent response rate. Findings indicate that the number…
How Are Cultural-Historical Change and Individual Cognition Related?
ERIC Educational Resources Information Center
Hatano, Giyoo
2005-01-01
The Geoffrey Saxe and Esmonde monograph (this issue) offers both fascinating empirical findings and intriguing theoretical insight about cultural change and individual cognition. Cultural and cognitive changes are "reciprocal processes," but how can these be related in research? One obvious way is to conduct longitudinal studies of the mutual…
ERIC Educational Resources Information Center
Tu, Kelly M.; Erath, Stephen A.; Pettit, Gregory S.; El-Sheikh, Mona
2014-01-01
This study examined whether the longitudinal association between parental directing of friendships (i.e., encouraging or discouraging certain friendships) and young adolescents' friendship adjustment (i.e., friendship quality and friends' positive characteristics) was moderated by skin conductance level reactivity (SCLR) to peer stress.…
2012 Alumni Perspectives Survey. Survey Report
ERIC Educational Resources Information Center
Leach, Laura
2012-01-01
Conducted in September 2011, this Alumni Perspectives Survey by the Graduate Management Admission Council (GMAC) is a longitudinal study of respondents to the Global Management Education Graduate Survey, the annual GMAC[R] exit survey of graduate management students in their final year of business school. This 12th annual report includes responses…
Prediction of Residential Independence of Special Education High School Students.
ERIC Educational Resources Information Center
Heal, Laird W.; Rusch, Frank
1994-01-01
The residential independence of students with disabilities who had exited high school was assessed, using data from 2,686 interviewees in the National Longitudinal Transition Study. Individual characteristics, such as intelligence, living skills, and bad conduct records, were better predictors of postschool living arrangement status than were…
Parent-Child Relationships of Boys in Different Offending Trajectories: A Developmental Perspective
ERIC Educational Resources Information Center
Keijsers, Loes; Loeber, Rolf; Branje, Susan; Meeus, Wim
2012-01-01
Background: This study tested the theoretical assumption that transformations of parent-child relationships in late childhood and adolescence would differ for boys following different offending trajectories. Methods: Using longitudinal multiinformant data of 503 boys (ages 7-19), we conducted Growth Mixture Modeling to extract offending…
Cross-Sectional Predictors of "Risk" for School Failure
ERIC Educational Resources Information Center
Petridou, Alexandra; Karagiorgi, Yiasemina
2016-01-01
Since school failure has detrimental effects on students and on society, education policy needs to address students "at risk," and support them to reach their potential. This study used data from the longitudinal national Programme for Functional Literacy (PfL) conducted in Cyprus to identify students "at risk" and aimed to…
ERIC Educational Resources Information Center
Mrug, Sylvie; Windle, Michael
2009-01-01
This study utilized cross-lagged longitudinal models to examine prospective, bidirectional relationships between witnessing violence and victimization and three adjustment variables--delinquency, conduct problems, and school connectedness. Participants included 603 early adolescent boys and girls (78% African American, 20% Caucasian). Witnessing…
Satisfaction with Hospital Care and Interventions after Pregnancy Loss.
ERIC Educational Resources Information Center
Lasker, Judith N.; Toedter, Lori J.
1994-01-01
Conducted longitudinal study of 194 women and men who experienced miscarriage, ectopic pregnancy, stillbirth, or newborn death to examine recommended interventions. Subjects were more satisfied if they had experienced intervention than if they had not, but having experienced more total interventions was not associated with lower grief or greater…
New Look at the Impact of Diversity. Commentary
ERIC Educational Resources Information Center
Leon, Raul A.
2010-01-01
Scott Jaschik's article, "New Look at the Impact of Diversity," invites the reader to explore the dynamics of racial diversity on the college environment, discussing the findings of a longitudinal study conducted at UCLA (University of California, Los Angeles) that provides empirical evidence that documents student's racial attitudes. In…
ERIC Educational Resources Information Center
Ruohotie-Lyhty, Maria
2011-01-01
This paper explores the professional development of 11 newly qualified foreign language teachers. It draws on a qualitative longitudinal study conducted at the University of Jyvaskyla, Finland between 2002 and 2009. The paper concentrates on the personal side of teacher development by analysing participants' discourses concerning language…
Alumni Perspectives Survey, 2010. Survey Report
ERIC Educational Resources Information Center
Sheikh, Sabeen
2010-01-01
During the months of April and September of 2009, the Graduate Management Admission Council[R] (GMAC[R]) conducted the Alumni Perspectives Survey, a longitudinal study of prior respondents to the Global Management Education Graduate Survey of management students nearing graduation. A total of 3,708 alumni responded to the April 2009 survey,…
Long-Term Adjustment of Infertile Couples Following Unsuccessful Medical Intervention
ERIC Educational Resources Information Center
Daniluk, Judith C.; Tench, Elizabeth
2007-01-01
A 33-month longitudinal study was conducted with 38 infertile couples making the transition to biological childlessness after unsuccessful fertility treatments. Changes in their levels of psychological distress; marital, sexual, and life satisfaction; and self-esteem were examined. Increased self-esteem and decreased sexual satisfaction were…
The Development of Teacher Perspectives.
ERIC Educational Resources Information Center
Tabachnick, B. Robert; And Others
Two-year longitudinal case studes were conducted of four teachers, beginning with the student teaching experience through the first year of teaching. The study explored ways in which teaching perspectives, evidenced at the end of student teaching, are strengthened or modified during the first year of teaching. It also sought to determine who and…
Life sciences payload definition and integration study. Volume 3: Appendices
NASA Technical Reports Server (NTRS)
1972-01-01
Detail design information concerning payloads for biomedical research projects conducted during space missions is presented. Subjects discussed are: (1) equipment modules and equipment item lists, (2) weight and volume breakdown by payload and equipment units, (3) longitudinal floor arrangement configuration, and (4) nonbaseline second generation layouts.
The Effects of Social Service Contact on Teenagers in England
ERIC Educational Resources Information Center
Henderson, Morag; Scourfield, Jonathan; Cheung, Sin Yi; Sharland, Elaine; Sloan, Luke
2016-01-01
Objective: This study investigated outcomes of social service contact during teenage years. Method: Secondary analysis was conducted of the Longitudinal Survey of Young People in England (N = 15,770), using data on reported contact with social services resulting from teenagers' behavior. Outcomes considered were educational achievement and…
Impact of a Blended Environment with m-Learning on EFL Skills
ERIC Educational Resources Information Center
Obari, Hiroyuki; Lambacher, Stephen
2014-01-01
A longitudinal study conducted from April 2013 to January 2014 sought to ascertain whether a blended learning (BL) environment incorporating m-learning could help Japanese undergraduates improve their English language skills. In this paper, various emerging technologies (including Globalvoice English, ATR CALL Brix, the mobile learning-oriented…
The Social Fabric and Innovation Diffusion: Symbolic Adoption of Food
ERIC Educational Resources Information Center
Sapp, Stephen G.; Korsching, Peter F.
2004-01-01
This study used a longitudinal, panel design to examine the effects of negative information acquisition, compliance with opinion leader endorsements, and social demographic characteristics on consumers' symbolic adoption of food irradiation. Data collection coincided with the first market test of irradiated food conducted by a commercial firm,…
ERIC Educational Resources Information Center
Huang, Ching-Hsu
2014-01-01
The class quasi-experiment was conducted to determine whether using computer simulation teaching strategy enhanced student understanding of statistics concepts for students enrolled in an introductory course. One hundred and ninety-three sophomores in hospitality management department were invited as participants in this two-year longitudinal…
Investigating Profiles of Lexical Quality in Preschool and Their Contribution to First Grade Reading
ERIC Educational Resources Information Center
Murphy, Kimberly A.; Farquharson, Kelly
2016-01-01
This longitudinal study investigated profiles of lexical quality domains in preschool children and the extent to which profile membership predicted reading comprehension in first grade. A latent profile analysis was conducted to classify 420 preschool children on lexical quality domains, including orthography, phonology, morphosyntax, and…
USDA-ARS?s Scientific Manuscript database
Shiga toxin-producing Escherichia coli (STEC) are important food-borne pathogens, which can cause serious illnesses, including hemorrhagic colitis and hemolytic uremic syndrome. To examine if pigs are potential animal reservoirs for human STEC infections, we conducted a longitudinal cohort study in ...
Tooth loss, dementia and neuropathology in the Nun study.
Stein, Pamela Sparks; Desrosiers, Mark; Donegan, Sara Jean; Yepes, Juan F; Kryscio, Richard J
2007-10-01
Numerous studies have linked dementia to the subsequent deterioration of oral health. Few investigators, however, have examined oral disease as a potential risk factor in the development of dementia. The authors conducted a study to investigate a potential association between a history of oral disease and the development of dementia. Longitudinal dental records supplemented data collected from 10 annual cognitive assessments of 144 Milwaukee participants in the Nun Study, a longitudinal study of aging and Alzheimer disease, who were 75 to 98 years old. Neuropathologic findings at autopsy were available for 118 participants who died. A low number of teeth increased the risk of higher prevalence and incidence of dementia. Participants with the fewest teeth had the highest risk of prevalence and incidence of dementia. Edentulism or very few (one to nine) teeth may be predictors of dementia late in life.
Farabee, David; Hawken, Angela; Griffith, Peter
2011-06-01
Increased recognition that addictive behaviors tend to be chronic and relapsing has led to a growing emphasis on longitudinal substance abuse research. The purpose of this study was to identify effective follow-up strategies used by National Institute on Drug Abuse-funded investigators who have conducted at least 1 study involving follow-up data collection from human subjects. A web-based survey was administered to a representative sample of National Institute on Drug Abuse-funded researchers (N = 153) with a history of conducting longitudinal research. Reported study response rates were generally high, although 27% of the studies fell below the 80% benchmark. Face-to-face and telephone-based interviews commanded the largest subject payments-2 to 3 times higher than compensation rates for collection of biologic samples. With regard to the presumed impact of low follow-up rates on the generalizability of study findings, one-third of investigators who compared baseline characteristics of those who did and did not participate in the follow-up found meaningful differences. Support was found for the hypothesis that follow-up rates and total compensation would be positively related, with the mean compensation amounts between studies achieving <80% follow-up rate versus those achieving rates ≥80%, revealing a statistically significant effect in the predicted direction. The majority of respondents reported difficulty in tracking and locating subjects, and study respondents often proved to be quite different from nonrespondents. Incentives improved follow-up rates to a point, although the relationship was not linear. Efforts to improve follow-up rates may be better spent on addressing tracking and locating logistics rather than on strategies to compel participation once the subject has been located.
Park, In-Jo; Chung Jung, Dong; Suk-Hyun Hwang, Samuel; Yeon Jung, Hee; Yoon, Jin-Sang; Kim, Chul-Eung; Min Ahn, Yong; Sik Kim, Yong
2016-01-15
We aimed to examine the longitudinal relationship between the personal and social functioning and anxiety symptoms in patients with schizophrenia. For this purpose, we confirmed the validity of the anxiety subscale of the Symptom-Checklist-90-Revised (SCL-90-R) and then applied the latent growth modeling method for longitudinal causal relationships. Five hundred and seventy-eight patients diagnosed with schizophrenia were evaluated and 369 patients were included in the study at baseline. After conducting Rasch model analyses for the validation of the anxiety subscale in the SCL-90-R, we applied latent growth model to determine the causal relationship between the PSP and the anxiety symptoms. The validity of the anxiety subscale of the SCL-90-R was confirmed based on the Rasch rating model, where the criteria for Infit, Outfit, item difficulty, and point-measure correlations were satisfied. The results from the latent growth model showed that the intercept and slope (rate of change) of the PSP negatively predicted the slope of anxiety symptoms along the longitudinal trajectory. Together with previous studies examining the predictive role of anxiety symptoms on quality of life, our longitudinal findings lend evidence for bidirectional effects between quality of life and anxiety symptoms. The transactional nature of the relationship between anxiety symptoms and quality of life warrant further investigation using a longitudinal cross-lagged design. The anxiety subscale of the SCL-90-R may be utilized by clinicians and researcher to make inferences about quality of life in addition to assessing anxiety symptoms in patients with schizophrenia. Copyright © 2015 Elsevier B.V. All rights reserved.
Subclinical bulimia predicts conduct disorder in middle adolescent girls.
Viinamäki, Anni; Marttunen, Mauri; Fröjd, Sari; Ruuska, Jaana; Kaltiala-Heino, Riittakerttu
2013-01-01
This study investigates the comorbidity and longitudinal associations between self-reported conduct disorder and subclinical bulimia in a community-based sample of Finnish adolescents in a 2-year prospective follow-up study. There are 2070 adolescents who participated in the survey as ninth graders (mean age 15.5) and followed-up 2 years later. The Youth Self-Report Externalizing scale was used to measure conduct disorder and DSM-IV-based questionnaire to measure bulimia. Co-occurrence of female conduct disorder and subclinical bulimia was found at ages 15 and 17. Subclinical bulimia among girls at age 15 was a risk factor for conduct disorder at age 17, but conduct disorder at age 15 was not predictive of subclinical bulimia at age 17. The pathway from bulimia to conduct disorder may be suggestive of an association with future borderline personality disorder among girls. Copyright © 2012 John Wiley & Sons, Ltd and Eating Disorders Association.
İlhan, Nesrin; Sukut, Özge; Akhan, Latife Utaş; Batmaz, Makbule
2016-04-01
The nurse education program affects many aspects of personal development. Nursing students gain skills in critical thinking and analysis and also develop communication and management skills. The four-year program may also have an effect on students' assertiveness and self-esteem. This study was conducted to determine the impact of the four-year higher nursing school educational program on students' self-esteem and assertiveness. Descriptive longitudinal design. The study took place at a Foundation University in Istanbul, Turkey over the period 2006-2010. The students' levels of self-esteem and assertiveness were assessed at the beginning and end of the first, second, third and fourth years of the program. Copyright © 2016 Elsevier Ltd. All rights reserved.
Pernice, Regina; Trlin, Andrew; Henderson, Anne; North, Nicola; Skinner, Monica
2009-05-01
To report findings on employment, duration of residence and mental health from a longitudinal study of 107 skilled immigrants to New Zealand from the People's Republic of China, India and South Africa. Demographic and employment data were collected by face-to-face interviews using a structured questionnaire that included (as the mental health instrument) the General Health Questionnaire 12 (GHQ-12). The initial interview took place after the immigrants had been resident in New Zealand for an average of five months. Four subsequent interviews were conducted annually (1999-2002) on or about the anniversary of the first interview. Rather than an initial euphoric period followed by a mental health crisis, the results indicated poor mental health status in the first two years irrespective of employment status. Thereafter, mental health slightly improved as did employment rates. A surprising result was that although the South Africans had the highest employment rate, there were neither substantial mental health differences among the three groups nor was there a significant improvement during the course of the longitudinal study.
A modulation technique for the measurement of the DC longitudinal Faraday effect
NASA Astrophysics Data System (ADS)
Hunte, Carlos
2018-03-01
A modulation of light technique, using a lock-in amplifier, is described and tested to investigate the longitudinal Faraday effect in isotropic media. The Faraday rotation is measured directly from the lock-in amplifier. The Verdet constant and dispersion of lead-silica SF-59 Schott glass, at room temperature of 25 °C, were determined for varying wavelengths and expressions for their wavelength dependence were determined. The Verdet constant of water is also investigated. The results compare extremely well with other studies. The technique is suited to measure very small Verdet constants and can be easily conducted in an upper-level undergraduate laboratory.
Weight- and race-based bullying: health associations among urban adolescents.
Rosenthal, Lisa; Earnshaw, Valerie A; Carroll-Scott, Amy; Henderson, Kathryn E; Peters, Susan M; McCaslin, Catherine; Ickovics, Jeannette R
2015-04-01
Stigma-based bullying is associated with negative mental and physical health outcomes. In a longitudinal study, surveys and physical assessments were conducted with mostly Black and Latino, socioeconomically disadvantaged, urban students. As hypothesized, greater weight- and race-based bullying each was significantly indirectly associated with increased blood pressure and body mass index, as well as decreased overall self-rated health across 2 years, through the mechanism of more negative emotional symptoms. Results support important avenues for future research on mechanisms and longitudinal associations of stigma-based bullying with health. Interventions are needed to reduce stigma-based bullying and buffer adolescents from adverse health effects. © The Author(s) 2013.
Weight- and race-based bullying: Health associations among urban adolescents
Rosenthal, Lisa; Earnshaw, Valerie A; Carroll-Scott, Amy; Henderson, Kathryn E; Peters, Susan M; McCaslin, Catherine; Ickovics, Jeannette R
2014-01-01
Stigma-based bullying is associated with negative mental and physical health outcomes. In a longitudinal study, surveys and physical assessments were conducted with mostly Black and Latino, socioeconomically disadvantaged, urban students. As hypothesized, greater weight- and race-based bullying each was significantly indirectly associated with increased blood pressure and body mass index, as well as decreased overall self-rated health across 2 years, through the mechanism of more negative emotional symptoms. Results support important avenues for future research on mechanisms and longitudinal associations of stigma-based bullying with health. Interventions are needed to reduce stigma-based bullying and buffer adolescents from adverse health effects. PMID:24155192
Mediator and moderator effects in developmental and behavioral pediatric research.
Rose, Brigid M; Holmbeck, Grayson N; Coakley, Rachael Millstein; Franks, Elizabeth A
2004-02-01
The terms mediation and moderation are defined and clarified with particular emphasis on the role of mediational and moderational analyses in developmental and behavioral pediatric research. The article highlights the applicability of mediational and moderational analyses to longitudinal, intervention, and risk and protective factor research, and it provides basic information about how these analyses might be conducted. Also included is a discussion of various ways that both mediator and moderator variables can be incorporated into a single model. The article concludes with extended examples of both types of analyses using a longitudinal pediatric study for illustration. The article provides recommendations for applying mediational and moderational research in clinical practice.
ERIC Educational Resources Information Center
Singh, Renu; Mukherjee, Protap
2018-01-01
Using unique panel data from Young Lives study conducted in undivided Andhra Pradesh, India, this mixed-method paper analyses gender differentials in completion of secondary education. Results show biased secondary school completion rates in favor of boys. Probit regression results highlight certain variables such as mothers' education, wealth,…
ERIC Educational Resources Information Center
Graves, Scott
2011-01-01
The purpose of this study was to examine correlates of being at expected grade level in reading in the third grade. Participants for this study were a nationally representative sample of African American children from the Early Childhood Longitudinal Study (ECLS-K). Multilevel modeling was conducted to determine significant predictors of academic…
ERIC Educational Resources Information Center
Berger-Tikochinski, Tal; Zion, Michal; Spektor-Levy, Ornit
2016-01-01
This is a five-year study conducted with junior high school students studying in a 1:1-laptop program in order to test the effects of the program on various measures related to the students: their attitudes, motivation, perceived school norms, self-efficacy, and behavioral intention towards learning with laptops, according to the Theory of Planned…
Thermal conductivity and thermal expansion of graphite fiber/copper matrix composites
NASA Technical Reports Server (NTRS)
Ellis, David L.; Mcdanels, David L.
1991-01-01
The high specific conductivity of graphite fiber/copper matrix (Gr/Cu) composites offers great potential for high heat flux structures operating at elevated temperatures. To determine the feasibility of applying Gr/Cu composites to high heat flux structures, composite plates were fabricated using unidirectional and cross-plied pitch-based P100 graphite fibers in a pure copper matrix. Thermal conductivity of the composites was measured from room temperature to 1073 K, and thermal expansion was measured from room temperature to 1050 K. The longitudinal thermal conductivity, parallel to the fiber direction, was comparable to pure copper. The transverse thermal conductivity, normal to the fiber direction, was less than that of pure copper and decreased with increasing fiber content. The longitudinal thermal expansion decreased with increasing fiber content. The transverse thermal expansion was greater than pure copper and nearly independent of fiber content.
Thermal conductivity and thermal expansion of graphite fiber-reinforced copper matrix composites
NASA Technical Reports Server (NTRS)
Ellis, David L.; Mcdanels, David L.
1993-01-01
The high specific conductivity of graphite fiber/copper matrix (Gr/Cu) composites offers great potential for high heat flux structures operating at elevated temperatures. To determine the feasibility of applying Gr/Cu composites to high heat flux structures, composite plates were fabricated using unidirectional and cross-plied pitch-based P100 graphite fibers in a pure copper matrix. Thermal conductivity of the composites was measured from room temperature to 1073 K, and thermal expansion was measured from room temperature to 1050 K. The longitudinal thermal conductivity, parallel to the fiber direction, was comparable to pure copper. The transverse thermal conductivity, normal to the fiber direction, was less than that of pure copper and decreased with increasing fiber content. The longitudinal thermal expansion decreased with increasing fiber content. The transverse thermal expansion was greater than pure copper and nearly independent of fiber content.
Computer-based learning in neuroanatomy: A longitudinal study of learning, transfer, and retention
NASA Astrophysics Data System (ADS)
Chariker, Julia H.
A longitudinal experiment was conducted to explore computer-based learning of neuroanatomy. Using a realistic 3D graphical model of neuroanatomy, and sections derived from the model, exploratory graphical tools were integrated into interactive computer programs so as to allow adaptive exploration. 72 participants learned either sectional anatomy alone or learned whole anatomy followed by sectional anatomy. Sectional anatomy was explored either in perceptually continuous animation or discretely, as in the use of an anatomical atlas. Learning was measured longitudinally to a high performance criterion. After learning, transfer to biomedical images and long-term retention was tested. Learning whole anatomy prior to learning sectional anatomy led to a more efficient learning experience. Learners demonstrated high levels of transfer from whole anatomy to sectional anatomy and from sectional anatomy to complex biomedical images. All learning groups demonstrated high levels of retention at 2--3 weeks.
Abrisham, Syyed Jalil; Karbasi, Mohammad Hosein Akhavan; Zare, Jalil; Behnamfar, Zahra; Tafti, Arefah Dehghani; Shishesaz, Behzad
2011-03-01
De Quervain disease is a mechanical tenosynovitis due to inadequacy volume between abductor pollicis longus, extensor pollicis brevis and their tunnel. Treatment methods include immobilization, steroid injections, and operation. For the first time Fritz De Quervain described surgical treatment of this disease. Since then, various ways of treatment have been reported. The purpose of this study is to compare the clinical outcomes of a longitudinal incision with a transverse incision in De Quervain disease. This was a randomized controlled clinical trial conducted in three hospitals in Iran, Yazd from March 2003 to September 2008. One hundred-twenty patients with De Quervain disease who did not respond to conservative treatment were operated with two different incisions. The patients were followed for three months to compare the surgical outcomes. During a three month follow-up, a significant difference was shown between the two methods (p=0.03). Results of surgical treatment with longitudinal incision were excellent (only 5 hypertrophic scars), but there were 13 postoperative complaints with transverse incision. According to our findings, longitudinal incision in surgical treatment of De Quervain disease is better than transverse incision.
Erbacher, Monica K; Schmidt, Karen M; Boker, Steven M; Bergeman, Cindy S
2012-01-01
Positive (PA) and negative affect (NA) are important constructs in health and well-being research. Good longitudinal measurement is crucial to conducting meaningful research on relationships between affect, health, and well-being across the lifespan. One common affect measure, the PANAS, has been evaluated thoroughly with factor analysis, but not with Racsh-based latent trait models (RLTMs) such as the Partial Credit Model (PCM), and not longitudinally. Current longitudinal RLTMs can computationally handle few occasions of data. The present study compares four methods of anchoring PCMs across 56 occasions to longitudinally evaluate the psychometric properties of the PANAS plus additional items. Anchoring item parameters on mean parameter values across occasions produced more desirable results than using no anchor, using first occasion parameters as anchors, or allowing anchor values to vary across occasions. Results indicated problems with NA items, including poor category utilization, gaps in the item distribution, and a lack of easy-to-endorse items. PA items had much more desirable psychometric qualities.
Sugiura, Minoru; Nakamura, Mieko; Ogawa, Kazunori; Ikoma, Yoshinori; Yano, Masamichi
2015-11-28
Recent epidemiological studies show the association of carotenoids with the metabolic syndrome (MetS), but thorough longitudinal cohort studies regarding this association have not been well conducted. The objective of this study was to investigate longitudinally whether serum carotenoids are associated with the risk of developing the MetS and its components in Japanese subjects. We conducted a follow-up study on 1073 men and women aged 30-79 years at the baseline from the Mikkabi prospective cohort study. Those who participated in the baseline and completed follow-up surveys were examined longitudinally. Over the 10-year period, 910 subjects (295 men and 615 women) took part in the follow-up survey at least once. Over a mean follow-up period of 7·8 (sd 2·9) years, thirty-six men and thirty-one women developed new MetS. After adjustments for confounders, the hazard ratio (HR) for the MetS in the highest tertile of serum β-carotene against the lowest tertile was 0·47 (95 % CI 0·23, 0·95). On the other hand, significantly lower risks for dyslipidaemia were observed in the highest tertiles of serum α- and β-carotene and β-cryptoxanthin (HR 0·66; 95 % CI 0·46, 0·96; HR, 0·54; 95 % CI 0·37, 0·79; and HR 0·66; 95 % CI 0·44, 0·99, respectively). Other significant associations between the risks for obesity, high blood pressure and hyperglycaemia with serum carotenoids were not observed. Our results further support the hypothesis that eating a diet rich in carotenoids might help prevent the development of the MetS and its complications in Japanese subjects.
Bursch, B; Lester, P; Jiang, L; Rotheram-Borus, M J; Weiss, R
2008-07-01
The objective of this study was to identify salient parent and adolescent psychosocial factors related to somatic symptoms in adolescents. As part of a larger intervention study conducted in New York, 409 adolescents were recruited from 269 parents with HIV. A longitudinal model predicted adolescent somatization scores six years after baseline assessment. Adolescent somatic symptoms were assessed at baseline and at 3-month intervals for the first two years and then at 6-month intervals using the Brief Symptom Inventory. Baseline data from adolescents and parents were used to predict adolescent somatic symptoms. Variables related to increased adolescent somatic symptoms over six years included being younger and female; an increased number of adolescent medical hospitalizations; more stressful life events; adolescent perception of a highly rejecting parenting style; more parent-youth conflict; no experience of parental death; and parental distress over their own pain symptoms. Our findings extend the literature by virtue of the longitudinal design; inclusion of both parent and child variables in one statistical model; identification of study participants by their potentially stressful living condition rather than by disease or somatic symptom status; and inclusion of serious parental illness and death in the study.
Evaluating the Impacts of ICT Use: A Multi-Level Analysis with Hierarchical Linear Modeling
ERIC Educational Resources Information Center
Song, Hae-Deok; Kang, Taehoon
2012-01-01
The purpose of this study is to evaluate the impacts of ICT use on achievements by considering not only ICT use, but also the process and background variables that influence ICT use at both the student- and school-level. This study was conducted using data from the 2010 Survey of Seoul Education Longitudinal Research. A Hierarchical Linear…
ERIC Educational Resources Information Center
Al Baghal, Tarek
2017-01-01
Prior studies suggest memories are potentially error prone. Proactive dependent interviewing (PDI) is a possible method to reduce errors in reports of change in longitudinal studies, reminding respondents of previous answers while asking if there has been any change since the last survey. However, little research has been conducted on the impact…
ERIC Educational Resources Information Center
Population Reference Bureau, Inc., Washington, DC.
This briefing paper describes research findings on factors linked to children's school achievement and emotional adjustment. The findings are based on the Child Development Supplement of the Panel Study of Income Dynamics, a nationally representative, longitudinal study of children and families conducted at the University of Michigan and supported…
ERIC Educational Resources Information Center
Wegge, Denis; Vandebosch, Heidi; Eggermont, Steven; Pabian, Sara
2016-01-01
The present study examines the reciprocal associations between cyberbullying behavior and young adolescents' social status. For this purpose, a two-wave panel study with an 8-month time interval was conducted among an entire grade of 154 secondary school pupils (age 12-14). The survey featured items on traditional bullying and cyberbullying as…
ERIC Educational Resources Information Center
Forster, Greg
2007-01-01
This study presents new findings comparing public and private high schools using top-quality data from the Education Longitudinal Study (ELS), a long-term research project sponsored by the U.S. Department of Education. The ELS project tracks individual data on thousands of students, allowing researchers to conduct much better analyses than are…
ERIC Educational Resources Information Center
Piekny, Jeanette; Grube, Dietmar; Maehler, Claudia
2013-01-01
The focus of the present study is on the developmental antecedents of domain-general experimentation skills. We hypothesized that false-belief understanding would predict the ability to distinguish a conclusive from an inconclusive experiment. We conducted a longitudinal study with two assessment points (t1 and t2) to investigate this hypothesis.…
ERIC Educational Resources Information Center
von Soest, Tilmann; Wichstrom, Lars
2009-01-01
This study examines gender differences in the development of dieting among a representative sample of 1,368 Norwegian boys and girls. The respondents were followed over 3 time points from ages 13/14 to 20/21. Latent growth curve analyses were conducted showing that girls' dieting scores increased while boys' scores remained constant. Gender…
The Impact of Hearing Loss on Quality of Life in Older Adults
ERIC Educational Resources Information Center
Dalton, Dayna S.; Cruickshanks, Karen J.; Klein, Barbara E. K.; Klein, Ronald; Wiley, Terry L.; Nondahl, David M.
2003-01-01
Purpose: The authors investigate the impact of hearing loss on quality of life in a large population of older adults. Design and Methods: Data are from the 5-year follow-up Epidemiology of Hearing Loss Study, a population-based longitudinal study of age-related hearing impairment conducted in Beaver Dam, WI. Participants (N = 2,688) were 53-97…
ERIC Educational Resources Information Center
Tang, Eunice Lai-Yiu; Lee, John Chi-Kin; Chun, Cecilia Ka-Wai
2012-01-01
This study sets out to investigate how pre-service ESL teachers shape their beliefs in the process of experimenting with new teaching methods introduced in the teacher education programme. A 4-year longitudinal study was conducted with four randomly selected ESL pre-service teachers. Their theoretical orientations of ESL instruction were tracked…
ERIC Educational Resources Information Center
Nielsen, Sara E.; Yezierski, Ellen J.
2016-01-01
Academic tracking, placing students in different classes based on past performance, is a common feature of the American secondary school system. A longitudinal study of secondary students' chemistry self-concept scores was conducted, and one feature of the study was the presence of academic tracking. Though academic tracking is one way to group…
Infants' Early Visual Attention and Social Engagement as Developmental Precursors to Joint Attention
ERIC Educational Resources Information Center
Salley, Brenda; Sheinkopf, Stephen J.; Neal-Beevers, A. Rebecca; Tenenbaum, Elena J.; Miller-Loncar, Cynthia L.; Tronick, Ed; Lagasse, Linda L.; Shankaran, Seetha; Bada, Henrietta; Bauer, Charles; Whitaker, Toni; Hammond, Jane; Lester, Barry M.
2016-01-01
This study examined infants' early visual attention (at 1 month of age) and social engagement (4 months) as predictors of their later joint attention (12 and 18 months). The sample (n = 325), drawn from the Maternal Lifestyle Study, a longitudinal multicenter project conducted at 4 centers of the National Institute of Child Health and Human…
Economic Consequences of Marital Disruption for Women in Their Middle Years.
ERIC Educational Resources Information Center
Shaw, Lois B.
An analysis of data from the National Longitudinal Study (NLS) was conducted to determine whether marital disruption (by death, divorce, or separation) caused poverty in the early years after a marriage ends and whether the poverty was long-term or short-term. The study examined data on women who had experienced a disruption before 1967 and were…
ERIC Educational Resources Information Center
McEwin, C. Kenneth; Greene, Melanie W.
2010-01-01
While a number of studies have yielded useful information regarding the status of middle level schools in the United States, four linked national surveys provide a longitudinal perspective on the degree of implementation of key middle grades programs and practices. These studies were conducted in 1968 (Alexander, 1968), 1988 (Alexander &…
ERIC Educational Resources Information Center
Gorman, Michael F.
2011-01-01
A longitudinal study of information technology (IT) managers at a Fortune 200 company in the Southwest United States was conducted to assess the effectiveness of a training program at bridging the perceived business skills gap for IT employees. A needs assessment was carried out, resulting in a 4-module training program. The program was evaluated…
ERIC Educational Resources Information Center
Price, Sarah Kye
2008-01-01
Previous empirical studies of pregnancy loss have predominantly focused on complex grief response and emergent problems associated with future parenting in self-selected samples of bereaved women. This article presents findings from a retrospective secondary data analysis conducted with a racially and ethnically diverse sample of currently…
Schulz-Heik, R Jay; Rhee, Soo Hyun; Silvern, Louise E; Haberstick, Brett C; Hopfer, Christian; Lessem, Jeffrey M; Hewitt, John K
2010-05-01
It is often assumed that childhood maltreatment causes conduct problems via an environmentally mediated process. However, the association may be due alternatively to either a nonpassive gene-environment correlation, in which parents react to children's genetically-influenced conduct problems by maltreating them, or a passive gene-environment correlation, in which parents' tendency to engage in maltreatment and children's conduct problems are both influenced by a hereditary vulnerability to antisocial behavior (i.e. genetic mediation). The present study estimated the contribution of these processes to the association between maltreatment and conduct problems. Bivariate behavior genetic analyses were conducted on approximately 1,650 twin and sibling pairs drawn from a large longitudinal study of adolescent health (Add Health). The correlation between maltreatment and conduct problems was small; much of the association between maltreatment and conduct problems was due to a nonpassive gene-environment correlation. Results were more consistent with the hypothesis that parents respond to children's genetically-influenced conduct problems by maltreating them than the hypothesis that maltreatment causes conduct problems.
NASA Astrophysics Data System (ADS)
Helldén, Gustav F.; Solomon, Joan
2004-11-01
In this paper we will examine the persistence of misconceptions. We used data from a longitudinal study of personal ideas in 24 students' thinking about ecological processes. The results show students often speaking about personal experiences dating from an early age, to which they had also referred in similar interviews conducted years before. These data are compared with results from a different study of middle school physics students' thinking about energy and steam engines. After the new learning had been successfull completed and assessed, old ideas returned. These findings are used to set up a theoretical basis for understanding the longitudinal results. Findings from memory studies are shown to explicate the long-term effects of the passage of time and prompts for the recall of scientific concepts.
The Importance of Longitudinal Pretest-Posttest Designs in Estimating College Impact
ERIC Educational Resources Information Center
Seifert, Tricia A.; Pascarella, Ernest T.; Erkel, Sherri I.; Goodman, Kathleen M.
2010-01-01
In this chapter, the authors discuss the issue of research design in conducting inquiry on college impact and demonstrate the importance of longitudinal pretest-posttest designs in maximizing the internal validity of findings. They begin by discussing the strengths and weaknesses of different types of research design in the college impact…
Using National Education Longitudinal Data Sets in School Counseling Research
ERIC Educational Resources Information Center
Bryan, Julia A.; Day-Vines, Norma L.; Holcomb-McCoy, Cheryl; Moore-Thomas, Cheryl
2010-01-01
National longitudinal databases hold much promise for school counseling researchers. Several of the more frequently used data sets, possible professional implications, and strategies for acquiring training in the use of large-scale national data sets are described. A 6-step process for conducting research with the data sets is explicated:…
Development of sexual expectancies among adolescents: contributions by parents, peers and the media.
Ragsdale, Kathleen; Bersamin, Melina M; Schwartz, Seth J; Zamboanga, Byron L; Kerrick, Madeleine R; Grube, Joel W
2014-01-01
To expand the scant research on sexual expectancies development among non-sexually active adolescents, we examined the relationship between adolescents' exposure to four socializing agents--mother/female guardian, father/male guardian, peers, and television programs with high sexual content--and their endorsement of four sexual expectancies: social benefit, pleasure, social risk, and health risk. Data are from Waves 2 and 3 of a three-wave annual longitudinal study conducted among California adolescents, the majority of whom were not sexually active (N = 914, 84%). Structural equation models were conducted to examine cross-sectional and longitudinal associations between the socializing agents and the sexual expectancies. Cross-sectional results indicate associations between peer sexual communication and social benefit, pleasure, and social risk expectancies. A positive association was found between exposure to music videos and social benefit expectancies, and a negative association was found between exposure to music videos and health risk expectancies. Longitudinal results suggest that communication with peers positively predicted pleasure expectancies and negatively predicted social risk expectancies. No other socializing agents were associated with any sexual expectancies. An invariance test found that significant correlations were similar across the different age groups. Results suggest that efforts to support positive sexual decision making among non-sexually active adolescents should target peer sexual communication.
Development of Sexual Expectancies among Adolescents: Contributions by Parents, Peers and the Media
Ragsdale, Kathleen; Bersamin, Melina; Schwartz, Seth J.; Zamboanga, Byron L.; Kerrick, R.; Grube, Joel W.
2013-01-01
In order to expand the scant research on sexual expectancies development among non-sexually active adolescents, we examined the relationship between adolescents’ exposure to four socializing agents—mother/female guardian, father/male guardian, peers, and television programs with high sexual content—and their endorsement of four sexual expectancies: Social Benefit, Pleasure, Social Risk, and Health Risk. Data are from Waves 2–3 of a three-wave annual longitudinal study conducted among California adolescents, the majority of whom were non-sexually active (N=914, 84%). Structural equation models were conducted to examine cross-sectional and longitudinal associations between the socializing agents and the sexual expectancies. Cross-sectional results indicate associations between peer sexual communication and Social Benefit, Pleasure and Social Risk expectancies. A positive association was found between exposure to music videos and Social Benefit expectancies and a negative association was found between exposure to music videos and Health Risk expectancies. Longitudinal results suggest that communication with peers positively predicted Pleasure expectancies and negatively predicted Social Risk expectancies. No other socializing agents were associated with any sexual expectancies. An invariance test found that significant correlations were similar across the different age groups. Results suggest that efforts to support positive sexual decision-making among non-sexually active adolescents should target peer sexual communication. PMID:23631710
Brady, Roscoe O; Margolis, Allison; Masters, Grace A; Keshavan, Matcheri; Öngür, Dost
2017-08-01
Using resting-state functional magnetic resonance imaging (rsfMRI), we previously compared cohorts of bipolar I subjects in a manic state to those in a euthymic state to identify mood state-specific patterns of cortico-amygdala connectivity. Our results suggested that mania is reflected in the disruption of emotion regulation circuits. We sought to replicate this finding in a group of subjects with bipolar disorder imaged longitudinally across states of mania and euthymia METHODS: We divided our subjects into three groups: 26 subjects imaged in a manic state, 21 subjects imaged in a euthymic state, and 10 subjects imaged longitudinally across both mood states. We measured differences in amygdala connectivity between the mania and euthymia cohorts. We then used these regions of altered connectivity to examine connectivity in the longitudinal bipolar group using a within-subjects design. Our findings in the mania vs euthymia cohort comparison were replicated in the longitudinal analysis. Bipolar mania was differentiated from euthymia by decreased connectivity between the amygdala and pre-genual anterior cingulate cortex. Mania was also characterized by increased connectivity between amygdala and the supplemental motor area, a region normally anti-correlated to the amygdala in emotion regulation tasks. Stringent controls for movement effects limited the number of subjects in the longitudinal sample. In this first report of rsfMRI conducted longitudinally across mood states, we find that previously observed between-group differences in amygdala connectivity are also found longitudinally within subjects. These results suggest resting state cortico-amygdala connectivity is a biomarker of mood state in bipolar disorder. Copyright © 2017 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Temelkov, K. A.; Slaveeva, S. I.; Fedchenko, Yu I.; Chernogorova, T. P.
2018-03-01
Using the well-known Wassiljewa equation and a new simple method, the thermal conductivities of various 2- and 3-component gas mixtures were calculated and compared under gas-discharge conditions optimal for two prospective lasers excited in a nanosecond pulsed longitudinal discharge. By solving the non-stationary heat-conduction equation for electrons, a 2D numerical model was also developed for determination of the radial and temporal dependences of the electron temperature Te (r, t).
Booth, Charlotte; Songco, Annabel; Parsons, Sam; Heathcote, Lauren; Vincent, John; Keers, Robert; Fox, Elaine
2017-12-29
Optimal psychological development is dependent upon a complex interplay between individual and situational factors. Investigating the development of these factors in adolescence will help to improve understanding of emotional vulnerability and resilience. The CogBIAS longitudinal study (CogBIAS-L-S) aims to combine cognitive and genetic approaches to investigate risk and protective factors associated with the development of mood and impulsivity-related outcomes in an adolescent sample. CogBIAS-L-S is a three-wave longitudinal study of typically developing adolescents conducted over 4 years, with data collection at age 12, 14 and 16. At each wave participants will undergo multiple assessments including a range of selective cognitive processing tasks (e.g. attention bias, interpretation bias, memory bias) and psychological self-report measures (e.g. anxiety, depression, resilience). Saliva samples will also be collected at the baseline assessment for genetic analyses. Multilevel statistical analyses will be performed to investigate the developmental trajectory of cognitive biases on psychological functioning, as well as the influence of genetic moderation on these relationships. CogBIAS-L-S represents the first longitudinal study to assess multiple cognitive biases across adolescent development and the largest study of its kind to collect genetic data. It therefore provides a unique opportunity to understand how genes and the environment influence the development and maintenance of cognitive biases and provide insight into risk and protective factors that may be key targets for intervention.
Bolotnikov, Aleksey E [South Setauket, NY; Camarda, Giuseppe [Farmingville, NY; Cui, Yonggang [Upton, NY; James, Ralph B [Ridge, NY
2011-11-22
The preferred embodiments are directed to a high-energy detector that is electrically shielded using an anode, a cathode, and a conducting shield to substantially reduce or eliminate electrically unshielded area. The anode and the cathode are disposed at opposite ends of the detector and the conducting shield substantially surrounds at least a portion of the longitudinal surface of the detector. The conducting shield extends longitudinally to the anode end of the detector and substantially surrounds at least a portion of the detector. Signals read from one or more of the anode, cathode, and conducting shield can be used to determine the number of electrons that are liberated as a result of high-energy particles impinge on the detector. A correction technique can be implemented to correct for liberated electron that become trapped to improve the energy resolution of the high-energy detectors disclosed herein.
The Sociocultural Factors of Russian Stagnation and Modernization
ERIC Educational Resources Information Center
Lapin, N. I.
2012-01-01
An analysis of the results of six Russian Longitudinal Monitoring Surveys, "The Values and Interests of the Population of Russia" (1990, 1994, 1998, 2002, 2006, and 2010), conducted by the Center for the Study of Sociocultural Changes at the Institute of Philosophy, Russian Academy of Sciences, provides evidence that two stages in the…
The Effects of Extensive Reading and Reading Strategies on Reading Self-Efficacy
ERIC Educational Resources Information Center
Burrows, Lance
2012-01-01
This study is a quasi-experimental, longitudinal investigation into the role that extensive reading and reading strategies play in the cultivation of reading self-efficacy. Conducted over the course of one academic year, how changes in reading self-efficacy translate into changes in reading comprehension was examined. In addition, the…
Social Support, Unfulfilled Expectations, and Affective Well-Being on Return to Employment
ERIC Educational Resources Information Center
Seiger, Christine P.; Wiese, Bettina S.
2011-01-01
We conducted a longitudinal study to investigate how social support from the partner is related to mothers' affective well-being during their return to employment after maternity leave and whether expectations of that support have an additional impact. We differentiated four forms of support and their respective expectation discrepancies:…
Communicative Interaction and Second Language Acquisition: An Inuit Example.
ERIC Educational Resources Information Center
Crago, Martha B.
1993-01-01
The role of cultural context in the communicative interaction of young Inuit children, their caregivers, and their non-Inuit teachers was examined in a longitudinal ethnographic study conducted in two small communities of arctic Quebec. Focus was on discourse features of primary language socialization of Inuit families. (32 references) (Author/LB)
ERIC Educational Resources Information Center
Cortes, Adriana M.; Saltzman, Kassey M.; Weems, Carl F.; Regnault, Heather P.; Reiss, Allan L.; Carrion, Victor G.
2005-01-01
Objective: The current study was conducted to determine if post-traumatic stress disorder (PTSD) symptomatology predicted later development of non-PTSD anxiety disorders in children and adolescents victimized by interpersonal trauma. Methods: Thirty-four children with a history of interpersonal trauma and no initial diagnosis of anxiety disorder…
ERIC Educational Resources Information Center
Doren, Bonnie; Gau, Jeff M.; Lindstrom, Lauren E.
2012-01-01
A secondary analysis was conducted of the National Longitudinal Transition Study-2 to examine (a) main effects of parents' school and postschool outcome expectations on the actual outcomes achieved, (b) demographic moderators, and (c) adolescent autonomy as a mediator of parent expectations and outcomes. Parent expectations were found to…
The Transition from School to Adulthood.
ERIC Educational Resources Information Center
Mott, Frank L.; Shaw, Lois B.
A study was conducted on the transition to adulthood among women, age fourteen through twenty-four, who were high school dropouts or who did not attend college immediately after high school. Data for 1968-73 was gathered in interviews and from the National Longitudinal Surveys of Labor Market Experience. The information obtained was related to the…
The Influence of Small Class Size, Duration, Intensity, and Heterogeneity on Head Start Fade
ERIC Educational Resources Information Center
Huss, Christopher D.
2010-01-01
The researcher conducted a nonexperimental study to investigate and analyze the influence of reduced class sizes, intensity (all day and every day), duration (five years), and heterogeneity (random class assignment) on the Head Start Fade effect. The researcher employed retrospective data analysis using a longitudinal explanatory design on data…
ERIC Educational Resources Information Center
Schwartz, Seth J.; Des Rosiers, Sabrina; Huang, Shi; Zamboanga, Byron L.; Unger, Jennifer B.; Knight, George P.; Pantin, Hilda; Szapocznik, Jose
2013-01-01
This study examined longitudinal acculturation patterns, and their associations with family functioning and adolescent risk behaviors, in Hispanic immigrant families. A sample of 266 Hispanic adolescents (M[subscript age] = 13.4) and their primary parents completed measures of acculturation, family functioning, and adolescent conduct problems,…
ERIC Educational Resources Information Center
Kutaka, Traci Shizu; Smith, Wendy M.; Albano, Anthony D.; Edwards, Carolyn Pope; Ren, Lixin; Beattie, Heidi Lynn; Lewis, W. James; Heaton, Ruth M.; Stroup, Walter W.
2017-01-01
The present study investigated the effects of "Primarily Math", an inservice elementary mathematics specialist program. "Primarily Math" sought to augment the mathematical knowledge for teaching of kindergarten through third-grade teachers using a longitudinal multiple cohort design. Two sets of analyses were conducted. The…
ERIC Educational Resources Information Center
Hergenrather, Kenneth C.; Emmanuel, Diona; McGuire-Kuletz, Maureen; Rhodes, Scott D.
2018-01-01
Purpose: To explore employment as a social determinant of health through examining the relationship between neurocognitive function and employment status. Method: The authors explored the causal relationship between employment status and neurocognitive function by conducting a systematic review of 15 longitudinal studies. The identified studies…
ERIC Educational Resources Information Center
Headley, Marcia Gail; Swoboda, Christopher M.; Foote, Lori
2016-01-01
"What works" policies are the latest incarnation of best practices in educational research. Instituted by various organisations internationally, they define what kind of research counts as "evidence" for reform-oriented decision-making. While some countries rely on systematic analyses and meta-analyses, the U.S. favours primary…
The Changing World View of Minority Migrants in an Urban Setting.
ERIC Educational Resources Information Center
Shannon, Lyle W.
A series of "world view" or value orientation questions were utilized in generating scale scores that sharply differentiated representative samples of Mexican Americans (280), Negroes (280), and Anglos (413) in a longitudinal study. The original interviews were conducted in 1959, 1960, and 1961. In 1971, seventy-four percent of the original…
A Behaviour-Genetic Analysis of Orthographic Learning, Spelling and Decoding
ERIC Educational Resources Information Center
Byrne, Brian; Coventry, William L.; Olson, Richard K.; Hulslander, Jacqueline; Wadsworth, Sally; DeFries, John C.; Corley, Robin; Willcutt, Erik G.; Samuelsson, Stefan
2008-01-01
As part of a longitudinal twin study of literacy and language, we conducted a behaviour-genetic analysis of orthographic learning, spelling and decoding in Grade 2 children (225 identical and 214 fraternal twin pairs) in the United States and Australia. Each variable showed significant genetic and unique environment influences. Multivariate…
Sibling Influences on the Career Plans of Male and Female Youth.
ERIC Educational Resources Information Center
Morgan, William R.
This study was conducted to establish the existence, direction, and size of sibling comparison effects on the occupational aspirations of youth. Data were drawn from the youth cohort subsample of the National Longitudinal Surveys of Labor Market Experience, sampling those with expressed occupational aspirations who come from homes with four or…
Spousal Caregiver Narratives and Credible Authority: Uncertainty in Illness of Spousal Caregivers
ERIC Educational Resources Information Center
Sodowsky, Karen
2012-01-01
This article is taken from a larger longitudinal study that used caregiver interviews, caregiver surveys, and caregiver statistical information of one community. The interviews were conducted with six spousal caregivers to examine the narratives produced by spouses actively caring for their partners with dementia. The spousal caregivers were…
ERIC Educational Resources Information Center
Byrnes, James P.; Wasik, Barbara A.
2009-01-01
A secondary analysis of the Early Childhood Longitudinal Study-Kindergarten Sample (N = 17,401) was conducted to determine the factors that are most strongly associated with math achievement during kindergarten, first grade, and third grade. Factors from the following three categories were considered: antecedent factors (e.g., family…
ERIC Educational Resources Information Center
Strayhorn, Terrell L.
2010-01-01
Using data from the National Education Longitudinal Study (NELS;1988/2000), the author conducted hierarchical linear regression analyses, with a nested design, to estimate the influence of affective variables--parent involvement, teacher perceptions, and school environments--on Black students' math achievement in grade 10. Drawing on…
ERIC Educational Resources Information Center
Datnow, Amanda; Hubbard, Lea; Woody, Elisabeth
In 1997, California became the first state to conduct large-scale experimentation with single gender public education. This longitudinal study examined the impact of single gender academies in six California districts, focusing on equity implications. Data from observations and interviews with educators, policymakers, and students indicated that…
Patterns of Non-Verbal Social Interactions within Intensive Mathematics Intervention Contexts
ERIC Educational Resources Information Center
Thomas, Jonathan Norris; Harkness, Shelly Sheats
2016-01-01
This study examined the non-verbal patterns of interaction within an intensive mathematics intervention context. Specifically, the authors draw on social constructivist worldview to examine a teacher's use of gesture in this setting. The teacher conducted a series of longitudinal teaching experiments with a small number of young, school-age…
Ninth Grade Course Enrollment and Dropping Out.
ERIC Educational Resources Information Center
Doss, David A.
An informal study was conducted of the courses selected by ninth grade students who later dropped out of high school. Longitudinal data were available for high school students in the Austin (Texas) Independent School District, from 1978-79 to 1982-83. The courses selected by high-risk students in ninth grade, including extracurricular activities…
ERIC Educational Resources Information Center
Blacher, Jan; Baker, Bruce L.; Kaladjian, Araksia
2013-01-01
This study examined the extent to which child syndromes and observation context related to mothers' parenting behaviors. Longitudinal observations were conducted of parenting behavior across ages 3, 4, and 5 years during structured and unstructured activities. The 183 participants included mothers of children with autism spectrum disorders,…
Update on National University Stress Study
ERIC Educational Resources Information Center
Winefield, Tony; Boyd, Carolyn; Saebel, Judith; Pignato, Silvia
2008-01-01
In 2003/4, 13 Australian universities took part in a follow-up survey of occupational stress following an earlier one conducted in 2000. More than 6000 staff participated at each time, of whom 969 (stayers) participated at both times. This paper presents the cross-sectional data obtained on both occasions as well as the longitudinal data provided…
ERIC Educational Resources Information Center
Center for Rural Policy and Development, 2006
2006-01-01
Since 2001 the Center for Rural Policy & Development (CRPD) has annually conducted surveys of rural Minnesota households to discern the level of computer ownership, Internet connectivity and broadband adoption throughout rural Minnesota. Since the beginning of this longitudinal effort, significant increases in technology adoption have been…
What Factors Predict Who Will Have a Strong Social Network Following a Stroke?
ERIC Educational Resources Information Center
Northcott, Sarah; Marshall, Jane; Hilari, Katerina
2016-01-01
Purpose: Measures of social networks assess the number and nature of a person's social contacts, and strongly predict health outcomes. We explored how social networks change following a stroke and analyzed concurrent and baseline predictors of social networks 6 months poststroke. Method: We conducted a prospective longitudinal observational study.…
Predicting First-Grade Reading Performance from Kindergarten Response to Tier 1 Instruction
ERIC Educational Resources Information Center
Al Otaiba, Stephanie; Folsom, Jessica S.; Schatschneider, Christopher; Wanzek, Jeanne; Greulich, Luana; Meadows, Jane; Li, Zhi; Connor, Carol M.
2011-01-01
Many schools are implementing multitier response-to-intervention (RTI) models to reduce reading difficulties. This study was part of our larger ongoing longitudinal RTI investigation within the Florida Learning Disabilities Center grant and was conducted in 7 ethnically and socioeconomically diverse schools. We observed reading instruction in 20…
The Impact of Tutoring on Early Reading Achievement for Children with and without Attention Problems
ERIC Educational Resources Information Center
Rabiner, David L.; Malone, Patrick S.
2004-01-01
This study examined whether the benefits of reading tutoring in first grade were moderated by children's level of attention problems. Participants were 581 children from the intervention and control samples of Fast Track, a longitudinal multisite investigation of the development and prevention of conduct problems. Standardized reading achievement…
The Development of Menstrual-Related Beliefs and Behaviors during Early Adolescence.
ERIC Educational Resources Information Center
Brooks-Gunn, Jeanne; Ruble, Diane N.
1982-01-01
A cross-sectional and a longitudinal study were conducted to answer questions about (1) the development and nature of premenstrual adolescent girls' expectations about menstrual symptoms, (2) expectations for and beliefs about menstrual symptoms as they relate to the actual experience of menarche, and (3) sources of information about menstruation…
Tracking the Career Paths of Marketing and Business Education Graduates
ERIC Educational Resources Information Center
Mooney, Carol; Haltinner, Urs; Stanislawski, Debbie
2006-01-01
Marketing and business education faculty at the University of Wisconsin-Stout (UW-Stout) recently conducted a longitudinal study, spanning the entire 35 years of the program's existence, describing and analyzing its graduates' career paths. Data was collected through a questionnaire that utilized a combination of Likert-type responses, open-ended…
Employment, Work Conditions, and the Home Environment in Single-Mother Families
ERIC Educational Resources Information Center
Lleras, Christy
2008-01-01
This study investigates the impact of employment status and work conditions on the quality of the home environment provided by single mothers of preschool-age children. Multivariate analyses were conducted using data from the National Longitudinal Survey of Youth. The results indicate that employment status is not a significant predictor of the…
Bringing Science to Bear: An Empirical Assessment of the Comprehensive Soldier Fitness Program
ERIC Educational Resources Information Center
Lester, Paul B.; McBride, Sharon; Bliese, Paul D.; Adler, Amy B.
2011-01-01
This article outlines the U.S. Army's effort to empirically validate and assess the Comprehensive Soldier Fitness (CSF) program. The empirical assessment includes four major components. First, the CSF scientific staff is currently conducting a longitudinal study to determine if the Master Resilience Training program and the Comprehensive…
Johnston, Bridget; Jindal-Snape, Divya; Pringle, Jan; Gold, Libby; Grant, Jayne; Dempsey, Raymond; Scott, Ros; Carragher, Pat
2016-01-01
Background: Care of young adults with life-limiting illnesses can often be complex due to the fact that they are growing and developing within the continuing presence of their illness. There is little research conducted nationally and internationally, which has examined the life issues of young adults or taken a longitudinal approach to understand such issues over a period of time. Aim: To gain clear understanding of one particular and pertinent life issue—relationship transition—occurring in the context of being a young adult with a life-limiting illness and the clinical needs arising from this. Design: This was a triangulated, longitudinal, qualitative study involving young adults with life-limiting illnesses and their significant others, namely, family members and healthcare professionals. Semi-structured interviews were conducted with participants and analysed using thematic analysis. Clinical case note reviews were also carried out. Setting/participants: A total of 12 young adults (aged between 17 and 23 years) from 2 hospices and 22 nominated significant others participated in a total of 58 interviews. Results: Thematic analysis revealed 4 main themes and 11 subthemes. The main themes were ‘Dependence dichotomy’, ‘In it together’, ‘Biographical uncertainty’, and ‘Conserving integrity’. These themes helped to establish the nature of relationship transitions that the young adult participants from the study experienced and additionally allowed insight into their possible needs at their end of life. Conclusion: This study has identified the nature of relationship transitions pertinent to young adults and has highlighted associated end of life clinical needs. This study can influence further research into the transitions and end of life needs of this particular patient group receiving palliative care, while informing the lacking evidence base which exists internationally. PMID:27781097
Magnetotransport properties of 8-Pmmn borophene: effects of Hall field and strain.
Islam, S K Firoz
2018-07-11
The polymorph of 8-Pmmn borophene is an anisotropic Dirac material with tilted Dirac cones at two valleys. The tilting of the Dirac cones at two valleys are in opposite directions, which manifests itself via the valley dependent Landau levels in presence of an in-plane electric field (Hall field). The valley dependent Landau levels cause valley polarized magnetotransport properties in presence of the Hall field, which is in contrast to the monolayer graphene with isotropic non-tilted Dirac cones. The longitudinal conductivity and Hall conductivity are evaluated by using linear response theory in low temperature regime. An analytical approximate form of the longitudinal conductivity is also obtained. It is observed that the tilting of the Dirac cones amplifies the frequency of the longitudinal conductivity oscillation (Shubnikov-de Haas). On the other hand, the Hall conductivity exhibits graphene-like plateaus except the appearance of valley dependent steps which are purely attributed to the Hall field induced lifting of the valley degeneracy in the Landau levels. Finally we look into the different cases when the Hall field is applied to the strained borophene and find that valley dependency is fully dominated by strain rather than Hall field. Another noticeable point is that if the real magnetic field is replaced by the strain induced pseudo magnetic field then the electric field looses its ability to cause valley polarized transport.
Wong, Michelle S; Jones-Smith, Jessica C; Colantuoni, Elizabeth; Thorpe, Roland J; Bleich, Sara N; Chan, Kitty S
2017-10-01
Fathers have increased their involvement in child caregiving; however, their changing role in childhood obesity is understudied. This study assessed the longitudinal association between changes in obesity among children aged 2 to 4 years and changes in fathers' involvement with raising children. Longitudinal data from the Early Childhood Longitudinal Study-Birth Cohort were used to conduct child fixed-effects linear and logistic regression analyses to assess the association between changes in childhood obesity-related outcomes (sugar-sweetened beverage consumption, screen time, BMI z score, overweight/obesity, obesity) and fathers' involvement with raising children (caregiving and influencing child-related decisions). Fixed-effects models control for all time-invariant characteristics. Analyses were controlled for time-varying confounders, including child age, maternal and paternal employment, and family poverty status. Children whose fathers increased their frequency of taking children outside and involvement with physical childcare experienced a decrease in their odds of obesity from age 2 to age 4. Obesity-related outcomes were not associated with fathers' decision-making influence. Increases in fathers' involvement with some aspects of caregiving may be associated with lower odds of childhood obesity. Encouraging fathers to increase their involvement with raising children and including fathers in childhood obesity prevention efforts may help reduce obesity risk among young children. © 2017 The Obesity Society.
Caregiver Self-Esteem as a Predictor of Patient Relationship Satisfaction: A Longitudinal Study.
Mroz, Emily L; Poulin, Michael J; Grant, Pei C; Depner, Rachel M; Breier, Jennifer; Byrwa, David J; Wright, Scott T
2018-03-01
Longitudinal assessment of patient-caregiver relationships will determine whether caregiver self-esteem determines patient relationship satisfaction at end of life. Research on close relationships and caregiving supports the idea that informal caregivers' self-esteem may influence their relationships with their terminally ill loved ones. However, this connection has not yet been investigated longitudinally, nor has it been applied specifically to care recipients' relationship satisfaction. A sample of 24 caregivers and 24 patients in a hospice home care program were recruited. Multiple patient and caregiver interviews were used to conduct a longitudinal study to measure fluctuations in patient health, changes in patient and caregiver relationship satisfaction, and self-esteem over a three-month period. An interaction between caregiver self-esteem and patient relationship satisfaction demonstrated the role that self-esteem plays between caregivers and patients enrolled in hospice care. Specifically, for patients with caregivers with low self-esteem, patient relationship satisfaction significantly decreased as the patient's physical health decreased, whereas for patients whose caregivers had high self-esteem, patient relationship satisfaction marginally increased during poorer physical health. High self-esteem may allow caregivers to overcome feelings of burden and maladaptive anticipatory grief to remain satisfied in their relationship with the patient. Caregiver self-esteem appears to play a role in fostering patient relationship satisfaction at the end of life.
Forster, Jeri E.; MaWhinney, Samantha; Ball, Erika L.; Fairclough, Diane
2011-01-01
Dropout is common in longitudinal clinical trials and when the probability of dropout depends on unobserved outcomes even after conditioning on available data, it is considered missing not at random and therefore nonignorable. To address this problem, mixture models can be used to account for the relationship between a longitudinal outcome and dropout. We propose a Natural Spline Varying-coefficient mixture model (NSV), which is a straightforward extension of the parametric Conditional Linear Model (CLM). We assume that the outcome follows a varying-coefficient model conditional on a continuous dropout distribution. Natural cubic B-splines are used to allow the regression coefficients to semiparametrically depend on dropout and inference is therefore more robust. Additionally, this method is computationally stable and relatively simple to implement. We conduct simulation studies to evaluate performance and compare methodologies in settings where the longitudinal trajectories are linear and dropout time is observed for all individuals. Performance is assessed under conditions where model assumptions are both met and violated. In addition, we compare the NSV to the CLM and a standard random-effects model using an HIV/AIDS clinical trial with probable nonignorable dropout. The simulation studies suggest that the NSV is an improvement over the CLM when dropout has a nonlinear dependence on the outcome. PMID:22101223
Farquharson, Kelly; Murphy, Kimberly A.
2016-01-01
Purpose: This paper describes methodological procedures involving execution of a large-scale, multi-site longitudinal study of language and reading comprehension in young children. Researchers in the Language and Reading Research Consortium (LARRC) developed and implemented these procedures to ensure data integrity across multiple sites, schools, and grades. Specifically, major features of our approach, as well as lessons learned, are summarized in 10 steps essential for successful completion of a large-scale longitudinal investigation in early grades. Method: Over 5 years, children in preschool through third grade were administered a battery of 35 higher- and lower-level language, listening, and reading comprehension measures (RCM). Data were collected from children, their teachers, and their parents/guardians at four sites across the United States. Substantial and rigorous effort was aimed toward maintaining consistency in processes and data management across sites for children, assessors, and staff. Conclusion: With appropriate planning, flexibility, and communication strategies in place, LARRC developed and executed a successful multi-site longitudinal research study that will meet its goal of investigating the contribution and role of language skills in the development of children's listening and reading comprehension. Through dissemination of our design strategies and lessons learned, research teams embarking on similar endeavors can be better equipped to anticipate the challenges. PMID:27064308
DiFrancesco, Robin; Rosenkranz, Susan L.; Taylor, Charlene R.; Pande, Poonam G.; Siminski, Suzanne M.; Jenny, Richard W.; Morse, Gene D.
2013-01-01
Among National Institutes of Health (NIH) HIV Research Networks conducting multicenter trials, samples from protocols that span several years are analyzed at multiple clinical pharmacology laboratories (CPLs) for multiple antiretrovirals (ARV). Drug assay data are, in turn, entered into study-specific datasets that are used for pharmacokinetic analyses, merged to conduct cross-protocol pharmacokinetic analysis and integrated with pharmacogenomics research to investigate pharmacokinetic-pharmacogenetic associations. The CPLs participate in a semi-annual proficiency testing (PT) program implemented by the Clinical Pharmacology Quality Assurance (CPQA) program. Using results from multiple PT rounds, longitudinal analyses of recovery are reflective of accuracy and precision within/across laboratories. The objectives of this longitudinal analysis of PT across multiple CPLs were to develop and test statistical models that longitudinally: (1)assess the precision and accuracy of concentrations reported by individual CPLs; (2)determine factors associated with round-specific and long-term assay accuracy, precision and bias using a new regression model. A measure of absolute recovery is explored as a simultaneous measure of accuracy and precision. Overall, the analysis outcomes assured 97% accuracy (±20% of the final target concentration of all (21)drug concentration results reported for clinical trial samples by multiple CPLs).Using the CLIA acceptance of meeting criteria for ≥2/3 consecutive rounds, all ten laboratories that participated in three or more rounds per analyte maintained CLIA proficiency. Significant associations were present between magnitude of error and CPL (Kruskal Wallis [KW]p<0.001), and ARV (KW p<0.001). PMID:24052065
DiFrancesco, Robin; Rosenkranz, Susan L; Taylor, Charlene R; Pande, Poonam G; Siminski, Suzanne M; Jenny, Richard W; Morse, Gene D
2013-10-01
Among National Institutes of Health HIV Research Networks conducting multicenter trials, samples from protocols that span several years are analyzed at multiple clinical pharmacology laboratories (CPLs) for multiple antiretrovirals. Drug assay data are, in turn, entered into study-specific data sets that are used for pharmacokinetic analyses, merged to conduct cross-protocol pharmacokinetic analysis, and integrated with pharmacogenomics research to investigate pharmacokinetic-pharmacogenetic associations. The CPLs participate in a semiannual proficiency testing (PT) program implemented by the Clinical Pharmacology Quality Assurance program. Using results from multiple PT rounds, longitudinal analyses of recovery are reflective of accuracy and precision within/across laboratories. The objectives of this longitudinal analysis of PT across multiple CPLs were to develop and test statistical models that longitudinally: (1) assess the precision and accuracy of concentrations reported by individual CPLs and (2) determine factors associated with round-specific and long-term assay accuracy, precision, and bias using a new regression model. A measure of absolute recovery is explored as a simultaneous measure of accuracy and precision. Overall, the analysis outcomes assured 97% accuracy (±20% of the final target concentration of all (21) drug concentration results reported for clinical trial samples by multiple CPLs). Using the Clinical Laboratory Improvement Act acceptance of meeting criteria for ≥2/3 consecutive rounds, all 10 laboratories that participated in 3 or more rounds per analyte maintained Clinical Laboratory Improvement Act proficiency. Significant associations were present between magnitude of error and CPL (Kruskal-Wallis P < 0.001) and antiretroviral (Kruskal-Wallis P < 0.001).
Chetboul, Valérie; Gouni, Vassiliki; Sampedrano, Carolina Carlos; Tissier, Renaud; Serres, François; Pouchelon, Jean-Louis
2007-01-01
Tissue Doppler Imaging (TDI) or strain (St) imaging could provide sensitive indices for early detection and treatment follow-up of canine dilated cardiomyopathy (DCM). Analysis of TDI and St features in dogs with overt DCM is a prerequisite before using these new criteria in prospective screenings of predisposed families or in clinical trials. Radial and longitudinal right and left myocardial motion, assessed by TDI and St variables, is altered in dogs with DCM. Case records for 26 dogs; 14 with DCM and 12 healthy controls of comparable age and weight were reviewed. A retrospective analysis was conducted of conventional echocardiography, 2-dimensional color TDI, and St imaging data. The DCM group was characterized by decreases in radial and longitudinal systolic velocity gradients of the left ventricular free wall (LVFW), radial and longitudinal absolute values of peak systolic St of the LVFW, and longitudinal systolic right ventricular (RV) velocities (all P < .001 versus control) associated with longitudinal postsystolic contraction waves in 7/14 dogs. Early diastolic LVFW velocities also were decreased for longitudinal (P < .01) and radial (P < .05) motions. All radial LVFW, longitudinal basal LVFW, and RV systolic velocities were negatively correlated with heart rate (P < .01). LV contractility along both the short and long axes is impaired in dogs with spontaneous DCM, as is systolic RV and diastolic LVFW function. These myocardial alterations are associated with an inverse force-frequency relationship. Studies now are needed to determine the comparative sensitivity of TDI and St variables for the early detection of canine DCM.
Holt, Cheryl L; Roth, David L; Huang, Jin; Park, Crystal L; Clark, Eddie M
2017-08-01
Many studies have examined associations between religious involvement and health, linking various dimensions of religion with a range of physical health outcomes and often hypothesizing influences on health behaviors. However, far fewer studies have examined explanatory mechanisms of the religion-health connection, and most have overwhelmingly relied on cross-sectional analyses. Given the relatively high levels of religious involvement among African Americans and the important role that religious coping styles may play in health, the present study tested a longitudinal model of religious coping as a potential mediator of a multidimensional religious involvement construct (beliefs; behaviors) on multiple health behaviors (e.g., diet, physical activity, alcohol use, cancer screening). A national probability sample of African Americans was enrolled in the RHIAA (Religion and Health In African Americans) study and three waves of telephone interviews were conducted over a 5-year period (N = 565). Measurement models were fit followed by longitudinal structural models. Positive religious coping decreased modestly over time in the sample, but these reductions were attenuated for participants with stronger religious beliefs and behaviors. Decreases in negative religious coping were negligible and were not associated with either religious beliefs or religious behaviors. Religious coping was not associated with change in any of the health behaviors over time, precluding the possibility of a longitudinal mediational effect. Thus, mediation observed in previous cross-sectional analyses was not confirmed in this more rigorous longitudinal model over a 5-year period. However, findings do point to the role that religious beliefs have in protecting against declines in positive religious coping over time, which may have implications for pastoral counseling and other faith-based interventions. Copyright © 2017 Elsevier Ltd. All rights reserved.
Gentile, Douglas A; Anderson, Craig A; Yukawa, Shintaro; Ihori, Nobuko; Saleem, Muniba; Ming, Lim Kam; Shibuya, Akiko; Liau, Albert K; Khoo, Angeline; Bushman, Brad J; Rowell Huesmann, L; Sakamoto, Akira
2009-06-01
Although dozens of studies have documented a relationship between violent video games and aggressive behaviors, very little attention has been paid to potential effects of prosocial games. Theoretically, games in which game characters help and support each other in nonviolent ways should increase both short-term and long-term prosocial behaviors. We report three studies conducted in three countries with three age groups to test this hypothesis. In the correlational study, Singaporean middle-school students who played more prosocial games behaved more prosocially. In the two longitudinal samples of Japanese children and adolescents, prosocial game play predicted later increases in prosocial behavior. In the experimental study, U.S. undergraduates randomly assigned to play prosocial games behaved more prosocially toward another student. These similar results across different methodologies, ages, and cultures provide robust evidence of a prosocial game content effect, and they provide support for the General Learning Model.
Risk Factors for Nipah Virus Infection among Pteropid Bats, Peninsular Malaysia
Rahman, Sohayati A.; Epstein, Jonathan H.; Mamat, Zaini C.; Yatim, Aziz M.; Hassan, Sharifah S.; Field, Hume E.; Hughes, Tom; Westrum, Justin; Naim, M.S.; Suri, Arshad S.; Jamaluddin, A. Aziz; Daszak, Peter
2013-01-01
We conducted cross-sectional and longitudinal studies to determine the distribution of and risk factors for seropositivity to Nipah virus (NiV) among Pteropus vampyrus and P. hypomelanus bats in Peninsular Malaysia. Neutralizing antibodies against NiV were detected at most locations surveyed. We observed a consistently higher NiV risk (odds ratio 3.9) and seroprevalence (32.8%) for P. vampyrus than P. hypomelanus (11.1%) bats. A 3-year longitudinal study of P. hypomelanus bats indicated nonseasonal temporal variation in seroprevalence, evidence for viral circulation within the study period, and an overall NiV seroprevalence of 9.8%. The seroprevalence fluctuated over the study duration between 1% and 20% and generally decreased during 2004–2006. Adult bats, particularly pregnant, with dependent pup and lactating bats, had a higher prevalence of NiV antibodies than juveniles. Antibodies in juveniles 6 months–2 years of age suggested viral circulation within the study period. PMID:23261015
Gentile, Douglas A.; Anderson, Craig A.; Yukawa, Shintaro; Ihori, Nobuko; Saleem, Muniba; Ming, Lim Kam; Shibuya, Akiko; Liau, Albert K.; Khoo, Angeline; Bushman, Brad J.; Huesmann, L. Rowell; Sakamoto, Akira
2009-01-01
Although dozens of studies have documented a relation between violent video games and aggressive behaviors, very little attention has been paid to potential effects of prosocial games. Theoretically, games in which game characters help and support each other in nonviolent ways should increase both short-term and long-term prosocial behaviors. We report three studies conducted in three countries with three age groups to test this hypothesis. In the correlational study, Singaporean middle-school students who played more prosocial games behaved more prosocially. In the two longitudinal samples of Japanese children and adolescents, prosocial game play predicted later increases in prosocial behavior. In the experimental study, U.S. undergraduates randomly assigned to play prosocial games behaved more prosocially toward another student. These similar results across different methodologies, ages, and cultures provide robust evidence a prosocial game content effect, and provide support for the General Learning Model. PMID:19321812
A Longitudinal Study of Memory Advantages in Bilinguals
Ljungberg, Jessica K.; Hansson, Patrik; Andrés, Pilar; Josefsson, Maria; Nilsson, Lars-Göran
2013-01-01
Typically, studies of cognitive advantages in bilinguals have been conducted previously by using executive and inhibitory tasks (e.g. Simon task) and applying cross-sectional designs. This study longitudinally investigated bilingual advantages on episodic memory recall, verbal letter and categorical fluency during the trajectory of life. Monolingual and bilingual participants (n = 178) between 35–70 years at baseline were drawn from the Betula Prospective Cohort Study of aging, memory, and health. Results showed that bilinguals outperformed monolinguals at the first testing session and across time both in episodic memory recall and in letter fluency. No interaction with age was found indicating that the rate of change across ages was similar for bilinguals and monolinguals. As predicted and in line with studies applying cross-sectional designs, no advantages associated with bilingualism were found in the categorical fluency task. The results are discussed in the light of successful aging. PMID:24023803
ERIC Educational Resources Information Center
Njenga, Ann; Kabiru, Margaret
Funding from the Bernard van Leer Foundation was used to conduct this longitudinal study in the Embu District of Kenya to compare the academic performance of children cared for by preschool teachers who had received different levels of training. Participating in the study were children from 18 preschools who were followed into primary school. In…
ERIC Educational Resources Information Center
Hammond, Cathy; Withington, Cairen; Sharp, Julia L.; Mobley, Catherine; Drew, Sam F.; Stringfield, Samuel C.; Stipanovic, Natalie; Swiger, Caroline M.; Daugherty, Lindsay; Griffith, Cathy
2014-01-01
This final report presents findings from data collection and analysis conducted during a five-year study by the National Dropout Prevention Center (NDPC) at Clemson University, in conjunction with colleagues from the National Research Center for Career and Technical Education (NRCCTE) at the University of Louisville. This project was one of three…
ERIC Educational Resources Information Center
Kerr, Elizabeth E.; And Others
This sub-study of a 39-month longitudinal study conducted by the University of Illinois in cooperation with the University of Iowa, undertook to discern the trends in practical nursing in Iowa and to record a history of its development. The 435 member 10 percent random sample of practical nurses licensed in Iowa through December 1965, which was…
Peñacoba, Cecilia; Rodríguez, Laura; Carmona, Javier; Marín, Dolores
2018-02-01
Agreeableness is associated with good mental health during pregnancy. Although different studies have indicated that agreeableness is related to adaptive coping, this relation has scarcely been studied in pregnant women. The aim of this study was to analyze the possible differences between high and low agreeableness in relation to coping strategies and psychiatric symptoms in pregnant women. We conducted a longitudinal prospective study between October 2009 and January 2013. Pregnant women (n = 285) were assessed in the first trimester of pregnancy, and 122 of them were assessed during the third. Data were collected using the Coping Strategies Questionnaire, the Symptom Check List 90-R, and the agreeableness subscale of the NEO-FFI. Using the SPSS 21 statistics package, binary logistic regression, two-way mixed analysis of variance, and multiple regression analyses and a Sobel test were conducted. Higher levels of agreeableness were associated with positive reappraisal and problem-solving, and lower levels of agreeableness were associated with overt emotional expression and negative self-focused coping. Women with low agreeableness had poorer mental health, especially in the first trimester. These findings should be taken into account to improve women's experiences during pregnancy. Nevertheless, given the scarcity of data, additional studies are needed.
A meta-analysis on progressive atrophy in intractable temporal lobe epilepsy
Caciagli, Lorenzo; Bernasconi, Andrea; Wiebe, Samuel; Koepp, Matthias J.; Bernasconi, Neda
2017-01-01
Objective: It remains unclear whether drug-resistant temporal lobe epilepsy (TLE) is associated with cumulative brain damage, with no expert consensus and no quantitative syntheses of the available evidence. Methods: We conducted a systematic review and meta-analysis of MRI studies on progressive atrophy, searching PubMed and Ovid MEDLINE databases for cross-sectional and longitudinal quantitative MRI studies on drug-resistant TLE. Results: We screened 2,976 records and assessed eligibility of 248 full-text articles. Forty-two articles met the inclusion criteria for quantitative evaluation. We observed a predominance of cross-sectional studies, use of different clinical indices of progression, and high heterogeneity in age-control procedures. Meta-analysis of 18/1 cross-sectional/longitudinal studies on hippocampal atrophy (n = 979 patients) yielded a pooled effect size of r = −0.42 for ipsilateral atrophy related to epilepsy duration (95% confidence interval [CI] −0.51 to −0.32; p < 0.0001; I2 = 65.22%) and r = −0.35 related to seizure frequency (95% CI −0.47 to −0.22; p < 0.0001; I2 = 61.97%). Sensitivity analyses did not change the results. Narrative synthesis of 25/3 cross-sectional/longitudinal studies on whole brain atrophy (n = 1,504 patients) indicated that >80% of articles reported duration-related progression in extratemporal cortical and subcortical regions. Detailed analysis of study design features yielded low to moderate levels of evidence for progressive atrophy across studies, mainly due to dominance of cross-sectional over longitudinal investigations, use of diverse measures of seizure estimates, and absence of consistent age control procedures. Conclusions: While the neuroimaging literature is overall suggestive of progressive atrophy in drug-resistant TLE, published studies have employed rather weak designs to directly demonstrate it. Longitudinal multicohort studies are needed to unequivocally differentiate aging from disease progression. PMID:28687722
Longitudinal Andhra Pradesh Eye Disease Study: rationale, study design and research methodology.
Khanna, Rohit C; Murthy, Gudlavalleti Vs; Marmamula, Srinivas; Mettla, Asha Latha; Giridhar, Pyda; Banerjee, Seema; Shekhar, Konegari; Chakrabarti, Subhabrata; Gilbert, Clare; Rao, Gullapalli N
2016-03-01
The rationale, objectives, study design and procedures for the longitudinal Andhra Pradesh Eye Disease Study are described. A longitudinal cohort study was carried out. Participants include surviving cohort from the rural component of Andhra Pradesh Eye Disease Study. During 1996-2000, Andhra Pradesh Eye Disease Survey was conducted in three rural (n = 7771) and one urban (n = 2522) areas (now called Andhra Pradesh Eye Disease Study 1). In 2009-2010, a feasibility exercise (Andhra Pradesh Eye Disease Study 2) for a longitudinal study (Andhra Pradesh Eye Disease Study 3) was undertaken in the rural clusters only, as urban clusters no longer existed. In Andhra Pradesh Eye Disease Study 3, a detailed interview will be carried out to collect data on sociodemographic factors, ocular and systemic history, risk factors, visual function, knowledge of eye diseases and barriers to accessing services. All participants will also undergo a comprehensive eye examination including photography of lens, optic disc and retina, Optic Coherence Tomography of the posterior segment, anthropometry, blood pressure and frailty measures. Measures include estimates of the incidence of visual impairment and age-related eye disease (lens opacities, glaucoma and age-related macular degeneration) and the progression of eye disease (lens opacities and myopia) and associated risk factors. Of the 7771 respondents examined in rural areas in Andhra Pradesh Eye Disease Study 1, 5447 (70.1%) participants were traced in Andhra Pradesh Eye Disease Study 2. These participants will be re-examined. Andhra Pradesh Eye Disease Study 3 will provide data on the incidence and progression of visual impairment and major eye diseases and their associated risk factors in India. The study will provide further evidence to aid planning eye care services. © 2015 Royal Australian and New Zealand College of Ophthalmologists.
Social Capital, Self-Esteem, and Use of Online Social Network Sites: A Longitudinal Analysis
ERIC Educational Resources Information Center
Steinfield, Charles; Ellison, Nicole B.; Lampe, Cliff
2008-01-01
A longitudinal analysis of panel data from users of a popular online social network site, Facebook, investigated the relationship between intensity of Facebook use, measures of psychological well-being, and bridging social capital. Two surveys conducted a year apart at a large U.S. university, complemented with in-depth interviews with 18 Facebook…
Time-of-Flight Adjustment Procedure for Acoustic Measurements in Structural Timber
Danbiel F. Llana; Guillermo Iñiguez-Gonzalez; Francisco Arriaga; Xiping Wang
2016-01-01
The effect of timber length on time-of-flight acoustic longitudinal measurements was investigated on the structural timber of four Spanish species: radiata pine (Pinus radiata D. Don), Scots pine (Pinus sylvestris L.), laricio pine (Pinus nigra Arn.), and maritime pine (Pinus pinaster Ait.). Time-of-flight longitudinal measurements were conducted on 120 specimens of...
A Longitudinal Analysis of an Out-of-School Science Experience
ERIC Educational Resources Information Center
Knapp, Doug
2007-01-01
A phenomenological approach was used to investigate the longitudinal recollections of participants of an out-of-school science program. The experience was a field trip to the Shenandoah National Park (USA) conducted in the fall of 2004. The science topic was geologic history and features related to the Shenandoah Valley. Two major themes relating…
Academies: A Model for School Improvement? Key Findings from a Five-Year Longitudinal Evaluation
ERIC Educational Resources Information Center
Armstrong, David; Bunting, Valerie; Larsen, Judy
2009-01-01
Academies were launched by David Blunkett, the then Secretary of State for Education, in March 2000 in a speech on transforming secondary education. PricewaterhouseCoopers LLP (PwC) was commissioned by the predecessor of the Department for Children, Schools and Families (DCSF) in February 2003 to conduct an independent longitudinal evaluation of…
ERIC Educational Resources Information Center
Kreppner, Jana M.; Rutter, Michael; Beckett, Celia; Castle, Jenny; Colvert, Emma; Groothues, Christine; Hawkins, Amanda; O'Connor, Thomas G.; Stevens, Suzanne; Sonuga-Barke, Edmund J. S.
2007-01-01
Longitudinal analyses on normal versus impaired functioning across 7 domains were conducted in children who had experienced profound institutional deprivation up to the age of 42 months and were adopted from Romania into U.K. families. Comparisons were made with noninstitutionalized children adopted from Romania and with nondeprived within-U.K.…
NASA Technical Reports Server (NTRS)
Stone, H. W.; Powell, R. W.
1977-01-01
A six-degree-of-freedom simulation analysis was conducted to examine the effects of longitudinal static aerodynamic stability and control uncertainties on the performance of the space shuttle orbiter automatic (no manual inputs) entry guidance and control systems. To establish the acceptable boundaries, the static aerodynamic characteristics were varied either by applying a multiplier to the aerodynamic parameter or by adding an increment. With either of two previously identified control system modifications included, the acceptable longitudinal aerodynamic boundaries were determined.
Huang, Jin; Vaughn, Michael G.
2016-01-01
This study examined the association between household food insecurity (insufficient access to adequate and nutritious food) and trajectories of externalising and internalising behaviour problems in children from kindergarten to fifth grade using longitudinal data from the Early Childhood Longitudinal Study—Kindergarten Cohort (ECLS-K), a nationally representative study in the USA. Household food insecurity was assessed using the eighteen-item standard food security scale, and children's behaviour problems were reported by teachers. Latent growth curve analysis was conducted on 7,348 children in the ECLS-K, separately for boys and girls. Following adjustment for an extensive array of confounding variables, results suggest that food insecurity generally was not associated with developmental change in children's behaviour problems. The impact of food insecurity on behaviour problems may be episodic or interact with certain developmental stages. PMID:27559210
Kaneita, Yoshitaka; Yokoyama, Eise; Harano, Satoru; Tamaki, Tetsuo; Suzuki, Hiroyuki; Munezawa, Takeshi; Nakajima, Hiromi; Asai, Takami; Ohida, Takashi
2009-08-01
A limited number of longitudinal studies have addressed the association between sleep disturbance and mental health status among adolescents. To examine whether each of these is a risk factor for the onset of the other, we conducted a prospective longitudinal study of Japanese adolescents. In 2004, we performed a baseline study of students attending three private junior high schools in Tokyo, and in 2006, a follow-up study was performed on the same population. The mean age of the subjects was 13 years. The Pittsburgh Sleep Quality Index was used to evaluate sleep disturbance, and the 12-item General Health Questionnaire was used to evaluate mental health status. The subjects were 698 students, of whom 516 were suitable for analysis. The incidence of newly developed poor mental health status during the 2 years leading to the follow-up study was 35.1%. New onset of poor mental health status was significantly associated with new onset of sleep disturbance and lasting sleep disturbance. The incidence of sleep disturbance during the 2 years leading to the follow-up study was 33.3%. New onset of sleep disturbance was significantly associated with new onset of poor mental health status and lasting poor mental health status. Sleep disturbance and poor mental health status increase each other's onset risk.
Multilingualism and fMRI: Longitudinal Study of Second Language Acquisition
Andrews, Edna; Frigau, Luca; Voyvodic-Casabo, Clara; Voyvodic, James; Wright, John
2013-01-01
BOLD fMRI is often used for the study of human language. However, there are still very few attempts to conduct longitudinal fMRI studies in the study of language acquisition by measuring auditory comprehension and reading. The following paper is the first in a series concerning a unique longitudinal study devoted to the analysis of bi- and multilingual subjects who are: (1) already proficient in at least two languages; or (2) are acquiring Russian as a second/third language. The focus of the current analysis is to present data from the auditory sections of a set of three scans acquired from April, 2011 through April, 2012 on a five-person subject pool who are learning Russian during the study. All subjects were scanned using the same protocol for auditory comprehension on the same General Electric LX 3T Signa scanner in Duke University Hospital. Using a multivariate analysis of covariance (MANCOVA) for statistical analysis, proficiency measurements are shown to correlate significantly with scan results in the Russian conditions over time. The importance of both the left and right hemispheres in language processing is discussed. Special attention is devoted to the importance of contextualizing imaging data with corresponding behavioral and empirical testing data using a multivariate analysis of variance. This is the only study to date that includes: (1) longitudinal fMRI data with subject-based proficiency and behavioral data acquired in the same time frame; and (2) statistical modeling that demonstrates the importance of covariate language proficiency data for understanding imaging results of language acquisition. PMID:24961428
Multilingualism and fMRI: Longitudinal Study of Second Language Acquisition.
Andrews, Edna; Frigau, Luca; Voyvodic-Casabo, Clara; Voyvodic, James; Wright, John
2013-05-28
BOLD fMRI is often used for the study of human language. However, there are still very few attempts to conduct longitudinal fMRI studies in the study of language acquisition by measuring auditory comprehension and reading. The following paper is the first in a series concerning a unique longitudinal study devoted to the analysis of bi- and multilingual subjects who are: (1) already proficient in at least two languages; or (2) are acquiring Russian as a second/third language. The focus of the current analysis is to present data from the auditory sections of a set of three scans acquired from April, 2011 through April, 2012 on a five-person subject pool who are learning Russian during the study. All subjects were scanned using the same protocol for auditory comprehension on the same General Electric LX 3T Signa scanner in Duke University Hospital. Using a multivariate analysis of covariance (MANCOVA) for statistical analysis, proficiency measurements are shown to correlate significantly with scan results in the Russian conditions over time. The importance of both the left and right hemispheres in language processing is discussed. Special attention is devoted to the importance of contextualizing imaging data with corresponding behavioral and empirical testing data using a multivariate analysis of variance. This is the only study to date that includes: (1) longitudinal fMRI data with subject-based proficiency and behavioral data acquired in the same time frame; and (2) statistical modeling that demonstrates the importance of covariate language proficiency data for understanding imaging results of language acquisition.
ERIC Educational Resources Information Center
Nalbone, David P.; Kovach, Ronald J.; Fish, Jessica N.; McCoy, Kelsey M.; Jones, Kathryn E.; Wright, Hillary Rawlings
2016-01-01
The current study investigated the potential role that social networking Web sites (e.g., Facebook) played in creating both actual and virtual learning communities within the first-year seminar. Researchers conducted a 2-year longitudinal study to assess whether students who were connected within a university-founded virtual network persisted in…
Development of Pain Endpoint Models for Use in Prostate Cancer Clinical Trials and Drug Approval
2017-10-01
publication delineating key methodological components of pain studies in prostate cancer. KEYWORDS Pain, metastatic castrate resistant prostate cancer...pain palliation and pain progression in prostate cancer clinical trials that are feasible, methodologically rigorous, and meet regulatory...requirements for drug approval and labeling. The primary aim of this award is to conduct an observational longitudinal study in men with castrate-resistant
ERIC Educational Resources Information Center
Billstedt, Eva; Gillberg, I. Carina; Gillberg, Christopher
2007-01-01
Background: Few studies have looked at the very long-term outcome of individuals with autism who were diagnosed in childhood. Methods: A longitudinal, prospective, community-based follow-up study of adults who had received the diagnosis of autism (classic and atypical) in childhood (n = 105) was conducted. A structured interview (the Diagnostic…
ERIC Educational Resources Information Center
Belmont, David; Odisharia, Irakli
2014-01-01
We conduct a longitudinal analysis of the NACUBO-Commonfund Study of Endowments (NCSE) results from 2006-2013 to evaluate if active management is related to higher endowment returns in U.S. equities over time. We also analyze the data to evaluate the endowment characteristics that are related to higher levels of performance over time. We find that…
ERIC Educational Resources Information Center
Lucyshyn, Joseph M.; Albin, Richard W.; Horner, Robert H.; Mann, Jane C.; Mann, James A.; Wadsworth, Gina
2007-01-01
This study examined the efficacy, social validity, and durability of a positive behavior support (PBS) approach with the family of a girl with autism and severe problem behavior. The study was conducted across a 10-year period beginning when the child was 5 years old. A multiple baseline across family routines design evaluated the functional…
ERIC Educational Resources Information Center
Kilmer, Theresa M.
2013-01-01
This study was conducted to determine the effectiveness of alternative middle school programs utilizing a longitudinal, mixed methods design and was driven by research questions which analyzed trends in attendance, discipline, and Standard of Learning test pass rates in history and science for 8 th, 9th, and 10th grade. It also examined student…
ERIC Educational Resources Information Center
Staklis, Sandra; Bentz, Alexander
2016-01-01
These Web Tables present information on the employment and enrollment status of first-time bachelor's degree recipients one year after graduation. The analysis uses data collected in the first follow-up surveys of three administrations of the Baccalaureate and Beyond Longitudinal Study (B&B). The first follow-up studies, conducted in 1994,…
ERIC Educational Resources Information Center
Fortuin, Janna; van Geel, Mitch; Vedder, Paul
2016-01-01
The present study was conducted to analyze whether in-class friends influence each other's grades, and whether adolescents tend to select friends that are similar to them in terms of academic achievement. During 1 academic year, 542 eighth-grade students (M age = 13.3 years) reported on 3 different occasions on their in-class friendship networks.…
One-Year Prediction of Pain Killer Use among At-Risk Older Teens and Emerging Adults
ERIC Educational Resources Information Center
Sussman, Steve; Rohrbach, Louise A.; Spruijt-Metz, Donna; Barnett, Elizabeth; Lisha, Nadra; Sun, Ping
2012-01-01
The leading substance of misuse among teens after tobacco, alcohol, and marijuana is the use of pain killers. Very few longitudinal studies on prediction of pain killer use have been conducted among teens. This study examined the 1-year prediction of self-reported last 30-day pain killer use controlling for baseline 30-day painkiller use among…
ACT-CCREC Core Research Program: Study Questions and Design. ACT Working Paper Series. WP-2015-01
ERIC Educational Resources Information Center
Cruce, Ty M.
2015-01-01
This report provides a non-technical overview of the guiding research questions and research design for the ACT-led core research program conducted on behalf of the GEAR UP College and Career Readiness Evaluation Consortium (CCREC). The core research program is a longitudinal study of the effectiveness of 14 GEAR UP state grants on the academic…
ERIC Educational Resources Information Center
Faulkner, Caroline
2015-01-01
This article draws on data collected from a wider, longitudinal life history study conducted in South Africa between 2010 and 2014. The study focussed specifically on the personal and professional pathways to principalship of a sample of women leaders of co-educational high schools in South Africa, in both rural and peri-urban provinces: a role…
ERIC Educational Resources Information Center
Empirical Education Inc., 2010
2010-01-01
PCI Education sought scientifically based evidence on the comparative effectiveness of the "PCI Reading Program" through a five-year longitudinal study. Phase 1 of the study consisted of a randomized control trial studying the efficacy of the "PCI Reading Program-Level One" that was conducted in the 2007-2008 in Miami-Dade…
Parkes, Alison; Sweeting, Helen; Wight, Daniel; Henderson, Marion
2013-05-01
Screen entertainment for young children has been associated with several aspects of psychosocial adjustment. Most research is from North America and focuses on television. Few longitudinal studies have compared the effects of TV and electronic games, or have investigated gender differences. To explore how time watching TV and playing electronic games at age 5 years each predicts change in psychosocial adjustment in a representative sample of 7 year-olds from the UK. Typical daily hours viewing television and playing electronic games at age 5 years were reported by mothers of 11 014 children from the UK Millennium Cohort Study. Conduct problems, emotional symptoms, peer relationship problems, hyperactivity/inattention and prosocial behaviour were reported by mothers using the Strengths and Difficulties Questionnaire. Change in adjustment from age 5 years to 7 years was regressed on screen exposures; adjusting for family characteristics and functioning, and child characteristics. Watching TV for 3 h or more at 5 years predicted a 0.13 point increase (95% CI 0.03 to 0.24) in conduct problems by 7 years, compared with watching for under an hour, but playing electronic games was not associated with conduct problems. No associations were found between either type of screen time and emotional symptoms, hyperactivity/inattention, peer relationship problems or prosocial behaviour. There was no evidence of gender differences in the effect of screen time. TV but not electronic games predicted a small increase in conduct problems. Screen time did not predict other aspects of psychosocial adjustment. Further work is required to establish causal mechanisms.
NASA Technical Reports Server (NTRS)
Nguyen, L. T.; Ogburn, M. E.; Gilbert, W. P.; Kibler, K. S.; Brown, P. W.; Deal, P. L.
1979-01-01
A real-time piloted simulation was conducted to evaluate the high-angle-of-attack characteristics of a fighter configuration based on wind-tunnel testing of the F-16, with particular emphasis on the effects of various levels of relaxed longitudinal static stability. The aerodynamic data used in the simulation was conducted on the Langley differential maneuvering simulator, and the evaluation involved representative low-speed combat maneuvering. Results of the investigation show that the airplane with the basic control system was resistant to the classical yaw departure; however, it was susceptible to pitch departures induced by inertia coupling during rapid, large-amplitude rolls at low airspeed. The airplane also exhibited a deep-stall trim which could be flown into and from which it was difficult to recover. Control-system modifications were developed which greatly decreased the airplane susceptibility to the inertia-coupling departure and which provided a reliable means for recovering from the deep stall.
NASA Astrophysics Data System (ADS)
Chen, M. N.; Su, W.; Deng, M. X.; Ruan, Jiawei; Luo, W.; Shao, D. X.; Sheng, L.; Xing, D. Y.
2016-11-01
A great deal of attention has been paid to the topological phases engineered by photonics over the past few years. Here, we propose a topological quantum phase transition to a quantum anomalous Hall (QAH) phase induced by off-resonant circularly polarized light in a two-dimensional system that is initially in a quantum spin Hall phase or a trivial insulator phase. This provides an alternative method to realize the QAH effect, other than magnetic doping. The circularly polarized light effectively creates a Zeeman exchange field and a renormalized Dirac mass, which are tunable by varying the intensity of the light and drive the quantum phase transition. Both the transverse and longitudinal Hall conductivities are studied, and the former is consistent with the topological phase transition when the Fermi level lies in the band gap. A highly controllable spin-polarized longitudinal electrical current can be generated when the Fermi level is in the conduction band, which may be useful for designing topological spintronics.
Borders, Tyrone F; Booth, Brenda M; Falck, Russel S; Leukefeld, Carl; Wang, Jichuan; Carlson, Robert G
2009-11-01
The primary objective of this study was to investigate whether drug use severity is associated with physical health-related quality of life (HRQL) over time. Data are from a longitudinal, multi-state, natural history community study of users of cocaine and/or methamphetamine who were interviewed at 6-month intervals over 2 years with a 79% follow-up participation rate. Physical HRQL was assessed with the physical component summary (PCS) of the SF-8 Health Survey and drug, alcohol, and psychiatric severity were all assessed with the Addiction Severity Index (ASI). Random coefficient regression analyses were conducted to test for longitudinal associations between the independent variables and SF-8 PCS scores. Reductions in drug use severity over time were accompanied by only minor improvements in SF-8 PCS scores, underscoring the potential long-term harm of illicit drug use on physical health. Greater psychiatric severity was strongly associated with lower SF-8 PCS scores, suggesting that clinical attention to mental health issues could potentially lead to improvements in perceived physical health as well as among stimulant users.
Booker, Cara L.; Skew, Alexandra J.; Kelly, Yvonne J.; Sacker, Amanda
2015-01-01
Objectives. We investigated the relationship between selected types of screen-based media (SBM) use, total SBM use, sports participation, and markers of well-being. Methods. Data came from the youth panel (n = 4899) of Understanding Society, the UK Household Longitudinal Study, conducted in 2009. Well-being was measured by the Strengths and Difficulties Questionnaire and markers of happiness in different life domains. Results. The majority of young people used multiple types of SBM for at least 1 hour per day; only 30% participated in sports every day. Overall, young people with heavy SBM use were less happy than moderate users and more likely to have socioemotional difficulties. Chatting on social networking Web sites and game console use were associated with higher odds of socioemotional problems. Higher total SBM use was associated with lower odds of happiness and higher odds of socioemotional difficulties. Greater participation in sports was associated with higher odds of happiness and lower odds of socioemotional difficulties. Conclusions. Further longitudinal research could inform future interventions to reduce sedentary behavior and encourage healthy lifestyles among young people. PMID:25494209
Daza, Eric J; Hudgens, Michael G; Herring, Amy H
Individuals may drop out of a longitudinal study, rendering their outcomes unobserved but still well defined. However, they may also undergo truncation (for example, death), beyond which their outcomes are no longer meaningful. Kurland and Heagerty (2005, Biostatistics 6: 241-258) developed a method to conduct regression conditioning on nontruncation, that is, regression conditioning on continuation (RCC), for longitudinal outcomes that are monotonically missing at random (for example, because of dropout). This method first estimates the probability of dropout among continuing individuals to construct inverse-probability weights (IPWs), then fits generalized estimating equations (GEE) with these IPWs. In this article, we present the xtrccipw command, which can both estimate the IPWs required by RCC and then use these IPWs in a GEE estimator by calling the glm command from within xtrccipw. In the absence of truncation, the xtrccipw command can also be used to run a weighted GEE analysis. We demonstrate the xtrccipw command by analyzing an example dataset and the original Kurland and Heagerty (2005) data. We also use xtrccipw to illustrate some empirical properties of RCC through a simulation study.
Body mass index, immune status, and virological control in HIV-infected men who have sex with men.
Blashill, Aaron J; Mayer, Kenneth H; Crane, Heidi M; Grasso, Chris; Safren, Steven A
2013-01-01
Prior cross-sectional studies have found inconsistent relationships between body mass index (BMI) and disease progression in HIV-infected individuals. Cross-sectional and longitudinal analyses were conducted on data from a sample of 864 HIV-infected men who have sex with men (MSM) obtained from a large, nationally distributed HIV clinical cohort. Of the 864 HIV-infected MSM, 394 (46%) were of normal weight, 363 (42%) were overweight, and 107 (12%) were obese at baseline. The baseline CD4 count was 493 (standard error [SE] = 9), with viral load (log10) = 2.4 (SE = .04), and 561 (65%) were virologically suppressed. Over time, controlling for viral load, highly active antiretroviral therapy (HAART) adherence, age, and race/ethnicity, overweight and obese HIV-infected men possessed higher CD4 counts than that of normal weight HIV-infected men. Further, overweight and obese men possessed lower viral loads than that of normal weight HIV-infected men. For HIV-infected MSM, in this longitudinal cohort study, possessing a heavier than normal BMI is longitudinally associated with improved immunological health.
Borders, Tyrone F.; Booth, Brenda M.; Falck, Russel S.; Leukefeld, Carl; Wang, Jichuan; Carlson, Robert G.
2009-01-01
The primary objective of this study was to investigate whether drug use severity is associated with physical health-related quality of life (HRQL) over time. Data are from a longitudinal, multi-state, natural history community study of users of cocaine and/or methamphetamine who were interviewed at 6-month intervals over 2 years with a 79% follow-up participation rate. Physical HRQL was assessed with the physical component summary (PCS) of the SF-8™ Health Survey and drug, alcohol, and psychiatric severity were all assessed with the Addiction Severity Index (ASI). Random coefficient regression analyses were conducted to test for longitudinal associations between the independent variables and SF-8 PCS scores. Reductions in drug use severity over time were accompanied by only minor improvements in SF-8 PCS scores, underscoring the potential long-term harm of illicit drug use on physical health. Greater psychiatric severity was strongly associated with lower SF-8 PCS scores, suggesting that clinical attention to mental health issues could potentially lead to improvements in perceived physical health as well among stimulant users. PMID:19560873
Hudgens, Michael G.; Herring, Amy H.
2017-01-01
Individuals may drop out of a longitudinal study, rendering their outcomes unobserved but still well defined. However, they may also undergo truncation (for example, death), beyond which their outcomes are no longer meaningful. Kurland and Heagerty (2005, Biostatistics 6: 241–258) developed a method to conduct regression conditioning on nontruncation, that is, regression conditioning on continuation (RCC), for longitudinal outcomes that are monotonically missing at random (for example, because of dropout). This method first estimates the probability of dropout among continuing individuals to construct inverse-probability weights (IPWs), then fits generalized estimating equations (GEE) with these IPWs. In this article, we present the xtrccipw command, which can both estimate the IPWs required by RCC and then use these IPWs in a GEE estimator by calling the glm command from within xtrccipw. In the absence of truncation, the xtrccipw command can also be used to run a weighted GEE analysis. We demonstrate the xtrccipw command by analyzing an example dataset and the original Kurland and Heagerty (2005) data. We also use xtrccipw to illustrate some empirical properties of RCC through a simulation study. PMID:29755297