Social Identities among Engineering Students and through Their Transition to Work: A Longitudinal Study

ERIC Educational Resources Information Center

Jungert, Tomas

2013-01-01

This article draws on a longitudinal and qualitative study of students in a master's program in engineering. Interpretative phenomenological analysis was used to analyze annual, semi-structured interviews with ten students, from the first semester until one year after graduation. The program enjoys a high status and has a reputation of being…

Longitudinal and Cross-Sectional Genetic Diversity in the Korean Peninsula Based on the P vivax Merozoite Surface Protein Gene.

PubMed

Kim, Jung-Yeon; Suh, Eun-Jung; Yu, Hyo-Soon; Jung, Hyun-Sik; Park, In-Ho; Choi, Yien-Kyeoug; Choi, Kyoung-Mi; Cho, Shin-Hyeong; Lee, Won-Ja

2011-12-01

Vivax malaria has reemerged and become endemic in Korea. Our study aimed to analyze by both longitudinal and cross-sectional genetic diversity of this malaria based on the P vivax Merozoite Surface Protein (PvMSP) gene parasites recently found in the Korean peninsula. PvMSP-1 gene sequence analysis from P vivax isolates (n = 835) during the 1996-2010 period were longitudinally analyzed and the isolates from the Korean peninsula through South Korea, the demilitarized zone and North Korea collected in 2008-2010 were enrolled in an overall analysis of MSP-1 gene diversity. New recombinant subtypes and severe multiple-cloneinfection rates were observed in recent vivax parasites. Regional variation was also observed in the study sites. This study revealed the great complexity of genetic variation and rapid dissemination of genes in P vivax. It also showed interesting patterns of diversity depending, on the region in the Korean Peninsula. Understanding the parasiteninsula. Under genetic variation may help to analyze trends and assess the extent of endemic malaria in Korea.

Analyzing longitudinal data with the linear mixed models procedure in SPSS.

PubMed

West, Brady T

2009-09-01

Many applied researchers analyzing longitudinal data share a common misconception: that specialized statistical software is necessary to fit hierarchical linear models (also known as linear mixed models [LMMs], or multilevel models) to longitudinal data sets. Although several specialized statistical software programs of high quality are available that allow researchers to fit these models to longitudinal data sets (e.g., HLM), rapid advances in general purpose statistical software packages have recently enabled analysts to fit these same models when using preferred packages that also enable other more common analyses. One of these general purpose statistical packages is SPSS, which includes a very flexible and powerful procedure for fitting LMMs to longitudinal data sets with continuous outcomes. This article aims to present readers with a practical discussion of how to analyze longitudinal data using the LMMs procedure in the SPSS statistical software package.

Unconventional Word Segmentation in Emerging Bilingual Students' Writing: A Longitudinal Analysis

ERIC Educational Resources Information Center

Sparrow, Wendy

2014-01-01

This study explores cross-language and longitudinal patterns in unconventional word segmentation in 25 emerging bilingual students' (Spanish/English) writing from first through third grade. Spanish and English writing samples were collected annually and analyzed for two basic types of unconventional word segmentation: hyposegmentation, in…

Approaches to Data Analysis in Longitudinal Field Investigations of Educational Programs.

ERIC Educational Resources Information Center

Jovick, Thomas D.

The federally funded longitudinal field study called Management Implications of Team Teaching (MITT) required a search for an appropriate strategy for analyzing through-time relationships among selected variables. The MITT project used questionnaires and interviews to collect data concerning the work, governance, attitudes, and orientation of…

Comparing statistical methods for analyzing skewed longitudinal count data with many zeros: an example of smoking cessation.

PubMed

Xie, Haiyi; Tao, Jill; McHugo, Gregory J; Drake, Robert E

2013-07-01

Count data with skewness and many zeros are common in substance abuse and addiction research. Zero-adjusting models, especially zero-inflated models, have become increasingly popular in analyzing this type of data. This paper reviews and compares five mixed-effects Poisson family models commonly used to analyze count data with a high proportion of zeros by analyzing a longitudinal outcome: number of smoking quit attempts from the New Hampshire Dual Disorders Study. The findings of our study indicated that count data with many zeros do not necessarily require zero-inflated or other zero-adjusting models. For rare event counts or count data with small means, a simpler model such as the negative binomial model may provide a better fit. Copyright © 2013 Elsevier Inc. All rights reserved.

Practical Knowledge and Teacher Reflection from a Practice-Based Literacy Teacher Education Program in the First Years: A Longitudinal Study

ERIC Educational Resources Information Center

Wetzel, Melissa Mosley; Hoffman, James V.; Roach, Audra K.; Russell, Katie

2018-01-01

This longitudinal study explores how one university's practice-based teacher preparation program prepared literacy teachers to develop practical knowledge for teaching and how that knowledge was tested and adapted in the first years of teaching. To understand change, we identified and analyzed points of tension, challenge, or dissonance in the…

Losing a Language in Childhood: A Longitudinal Case Study on Language Attrition

ERIC Educational Resources Information Center

Flores, Cristina

2015-01-01

This paper is based upon a longitudinal study of L2 attrition in a bilingual child who grew up in an L2 migration background (Germany) and moved to the country of origin (Portugal) at the age of nine, experiencing a "dominance shift from the L2 to the L1." The study aims to analyze the effects of language loss in L2 German. Data…

Parental Perceptions of Siblings' Grieving after a Childhood Cancer Death: A Longitudinal Study

ERIC Educational Resources Information Center

Barrera, Maru; Alam, Rifat; D'Agostino, Norma Mammone; Nicholas, David B.; Schneiderman, Gerald

2013-01-01

We investigated longitudinally parental perceptions of siblings' bereavement after childhood cancer death. Parents were interviewed 6 months (n = 25) and 18 months (n = 15) post-death. Data are analyzed combined and over time. The following themes emerged: (a) expression of grief: missing deceased child (verbally, crying), behavioral problems,…

A Fast EM Algorithm for Fitting Joint Models of a Binary Response and Multiple Longitudinal Covariates Subject to Detection Limits

PubMed Central

Bernhardt, Paul W.; Zhang, Daowen; Wang, Huixia Judy

2014-01-01

Joint modeling techniques have become a popular strategy for studying the association between a response and one or more longitudinal covariates. Motivated by the GenIMS study, where it is of interest to model the event of survival using censored longitudinal biomarkers, a joint model is proposed for describing the relationship between a binary outcome and multiple longitudinal covariates subject to detection limits. A fast, approximate EM algorithm is developed that reduces the dimension of integration in the E-step of the algorithm to one, regardless of the number of random effects in the joint model. Numerical studies demonstrate that the proposed approximate EM algorithm leads to satisfactory parameter and variance estimates in situations with and without censoring on the longitudinal covariates. The approximate EM algorithm is applied to analyze the GenIMS data set. PMID:25598564

A Short-Term Longitudinal Study of Memorial Development during Early Grade School.

ERIC Educational Resources Information Center

Kunzinger, Edward L., III

1985-01-01

Overt rehearsal and free recall performance was analyzed longitudinally in two experimental testing sessions at 7 and later at 9 years of age. Measures of short- and long-term memory recall, and two measures of input processing were obtained. Significant increases between age levels were exhibited by all variables except short-term memory.…

[Change settings for visual analyzer of child users of mobile communication: longitudinal study].

PubMed

Khorseva, N I; Grigor'ev, Iu G; Gorbunova, N V

2014-01-01

The paper represents theresults of longitudinal monitoring of the changes in the parameters of simple visual-motor reaction, the visual acuity and the rate of the visual discrimination in the child users of mobile communication, which indicate the multivariability of the possible effects of radiation from mobile phones on the auditory system of children.

Studies of longitudinal profile of electron bunches and impedance measurements at Indus-2 synchrotron radiation source

NASA Astrophysics Data System (ADS)

Garg, Akash Deep; Yadav, S.; Kumar, Mukesh; Shrivastava, B. B.; Karnewar, A. K.; Ojha, A.; Puntambekar, T. A.

2016-04-01

Indus-2 is a 3rd generation synchrotron radiation source at the Raja Ramanna Centre for Advanced Technology (RRCAT) in India. We study the longitudinal profile of electrons in Indus-2 by using dual sweep synchroscan streak camera at visible diagnostic beamline. In this paper, the longitudinal profiles of electron bunch are analyzed by filling beam current in a single bunch mode. These studies are carried at injection energy (550 MeV) and at ramped beam energy (2.5 GeV). The effects of the wakefield generated interactions between the circulating electrons and the surrounding vacuum chamber are analyzed in terms of measured effects on longitudinal beam distribution. The impedance of the storage ring is obtained by fitting the solutions of Haissinski equation to the measured bunch lengthening with different impedance models. The impedance of storage ring obtained by a series R+L impedance model indicates a resistance (R) of 1350±125 Ω, an inductance (L) of 180±25 nH and broadband impedance of 2.69 Ω. These results are also compared with the values obtained from measured synchronous phase advancing and scaling laws. These studies are very useful in better understanding and control of the electromagnetic interactions.

Use of Longitudinal Data in Genetic Studies in the Genome-wide Association Studies Era: Summary of Group 14

PubMed Central

Kerner, Berit; North, Kari E; Fallin, M Daniele

2010-01-01

Participants analyzed actual and simulated longitudinal data from the Framingham Heart Study for various metabolic and cardiovascular traits. The genetic information incorporated into these investigations ranged from selected single-nucleotide polymorphisms to genome-wide association arrays. Genotypes were incorporated using a broad range of methodological approaches including conditional logistic regression, linear mixed models, generalized estimating equations, linear growth curve estimation, growth modeling, growth mixture modeling, population attributable risk fraction based on survival functions under the proportional hazards models, and multivariate adaptive splines for the analysis of longitudinal data. The specific scientific questions addressed by these different approaches also varied, ranging from a more precise definition of the phenotype, bias reduction in control selection, estimation of effect sizes and genotype associated risk, to direct incorporation of genetic data into longitudinal modeling approaches and the exploration of population heterogeneity with regard to longitudinal trajectories. The group reached several overall conclusions: 1) The additional information provided by longitudinal data may be useful in genetic analyses. 2) The precision of the phenotype definition as well as control selection in nested designs may be improved, especially if traits demonstrate a trend over time or have strong age-of-onset effects. 3) Analyzing genetic data stratified for high-risk subgroups defined by a unique development over time could be useful for the detection of rare mutations in common multi-factorial diseases. 4) Estimation of the population impact of genomic risk variants could be more precise. The challenges and computational complexity demanded by genome-wide single-nucleotide polymorphism data were also discussed. PMID:19924713

Application of longitudinal and transversal bioimpedance measurements in peritoneal dialysis at 50 kHz

NASA Astrophysics Data System (ADS)

Nescolarde, L.; Doñate, T.; Casañas, R.; Rosell-Ferrer, J.

2010-04-01

More relevant information of the fluid changes in peritoneal dialysis (PD) might be obtained with segmental bioimpedance measurements rather than whole-body measurement, who hidden information of body composition. Whole-body and segmental bioimpedance measurements were obtained using 5 configurations (whole-body or right-side (RS), longitudinal-leg (L-LEG), longitudinal-abdomen (L-AB), transversal-abdomen (T-AB), and transversal-leg (T-LEG)) in 20 patients: 15 males (56.5 ± 9.4 yr, 24.2 ± 4.2 kg/m2) and 5 females (58.4 ± 7.1 yr, 28.2 ± 5.9 kg/m2) in peritoneal dialysis (PD). The aim of this study is to analyze the relationship between whole-body, longitudinal-segmental (L-LEG and L-AB) and transversal-segmental (TAB and TLEG) bioimpedance measurement at 50 kHz, with clinical parameters of cardiovascular risk, dyslipidemia, nutrition and hydration. The Kolmogorov-Smirnov test was used for the normality test of all variables. Longitudinal bioimpedance parameters were normalized by the height of the patients. The Spearman correlation was used to analyze the correlation between bioimpedance and clinical parameters. The statistical significance was considered with P < 0.05. Transversal bioimpedance measurements have higher correlation with clinical parameters than longitudinal measurements.

Children's Behavior Problems in the United States and Great Britain

ERIC Educational Resources Information Center

Parcel, Toby L.; Campbell, Lori Ann; Zhong, Wenxuan

2012-01-01

We analyze the effects of family capital on child behavior problems in the United States and Great Britain by comparing a longitudinal survey sample of 5- to 13-year-old children from the 1994 National Longitudinal Survey of Youth (N = 3,864) with a similar sample of children from the 1991 National Child Development Study "British Child"…

Concurrent and Longitudinal Predictors of Self-Esteem in Elementary and Middle School Girls

ERIC Educational Resources Information Center

Kutob, Randa M.; Senf, Janet H.; Crago, Marjorie; Shisslak, Catherine M.

2010-01-01

Background: The purpose of this study was to analyze the effects of factors related to self-esteem, both cross-sectionally and longitudinally, among 2 cohorts of girls over a period of 4 years, from elementary through middle school. Methods: A multiethnic sample of 656 elementary school girls recruited from 13 schools in Hayward, CA, and Tucson,…

Longitudinal Examination of Procrastination and Anxiety, and Their Relation to Self-Efficacy for Self- Regulated Learning: Latent Growth Curve Modeling

ERIC Educational Resources Information Center

Yerdelen, Sündüs; McCaffrey, Adam; Klassen, Robert M.

2016-01-01

This study investigated the longitudinal association between students' anxiety and procrastination and the relation of self-efficacy for self-regulation to these constructs. Latent Growth Curve Modeling was used to analyze data gathered from 182 undergraduate students (134 female, 48 male) at 4 times during a semester. Our results showed that…

Families in a High-Tech Age: Technology Usage Patterns, Work and Family Correlates, and Gender

ERIC Educational Resources Information Center

Chesley, Noelle

2006-01-01

This study analyzes a couple-level ("N" = 581), longitudinal data set of employees to provide evidence about technology use over time, the factors that predict use, and the potential for a spouse to influence an individual's use. Although longitudinal usage patterns suggest a trend toward adoption and use of e-mail, the Internet, cell phones, and…

Longitudinal Receptive American Sign Language Skills across a Diverse Deaf Student Body

ERIC Educational Resources Information Center

Beal-Alvarez, Jennifer S.

2016-01-01

This article presents results of a longitudinal study of receptive American Sign Language (ASL) skills for a large portion of the student body at a residential school for the deaf across four consecutive years. Scores were analyzed by age, gender, parental hearing status, years attending the residential school, and presence of a disability (i.e.,…

Sustaining School Improvement in a High-Need School: Longitudinal Analysis of Robbins Elementary School (USA) from 1993 to 2015

ERIC Educational Resources Information Center

Okilwa, Nathern; Barnett, Bruce

2017-01-01

Purpose: The purpose of this paper is to examine how Robbins ES has sustained high academic performance over almost 20 years despite several changes in principals. Design/methodology/approach: The paper analyzed longitudinal data based on: state-level academic and demographic data; two earlier studies of the school; and recent interviews with…

Analyzing the Origins of Childhood Externalizing Behavioral Problems

ERIC Educational Resources Information Center

Barnes, J. C.; Boutwell, Brian B.; Beaver, Kevin M.; Gibson, Chris L.

2013-01-01

Drawing on a sample of twin children from the Early Childhood Longitudinal Study, Birth Cohort (ECLS-B; Snow et al., 2009), the current study analyzed 2 of the most prominent predictors of externalizing behavioral problems (EBP) in children: (a) parental use of spankings and (b) childhood self-regulation. A variety of statistical techniques were…

[The clinical effect and disquisition of anterior cervical approach surgery with posterior longitudinal ligament hook pliers and posterior longitudinal ligament nip pliers].

PubMed

Kuang, Ling-hao; Xu, Dong; Sun, Ya-wei; Cong, Jie; Tian, Ji-wei; Wang, Lei

2010-09-21

To study the clinical effect of anterior cervical approach surgery to removal posterior longitudinal ligament (PLL) with posterior longitudinal ligament hook pliers and posterior longitudinal ligament nip pliers. To retrospectively analyzed anterior cervical approach surgery treatment 73 patients who were cervical spondylosis myelopathy. All patients removal PLL with self-make instrument, According to JOA grade to evaluate effect of operations. Full patients removal PLL were in succeed, in shape of extradural has renew, the JOA grade were increase, (12.8 ± 3.2) vs (8.3 ± 1.9). Removal PLL were increase effect of downright decompress in anterior cervical approach surgery, Operations become safety agile and reduce the complications with self-make instrument.

Dynamic Bayesian network modeling for longitudinal brain morphometry

PubMed Central

Chen, Rong; Resnick, Susan M; Davatzikos, Christos; Herskovits, Edward H

2011-01-01

Identifying interactions among brain regions from structural magnetic-resonance images presents one of the major challenges in computational neuroanatomy. We propose a Bayesian data-mining approach to the detection of longitudinal morphological changes in the human brain. Our method uses a dynamic Bayesian network to represent evolving inter-regional dependencies. The major advantage of dynamic Bayesian network modeling is that it can represent complicated interactions among temporal processes. We validated our approach by analyzing a simulated atrophy study, and found that this approach requires only a small number of samples to detect the ground-truth temporal model. We further applied dynamic Bayesian network modeling to a longitudinal study of normal aging and mild cognitive impairment — the Baltimore Longitudinal Study of Aging. We found that interactions among regional volume-change rates for the mild cognitive impairment group are different from those for the normal-aging group. PMID:21963916

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.

A longitudinal multilevel CFA-MTMM model for interchangeable and structurally different methods

PubMed Central

Koch, Tobias; Schultze, Martin; Eid, Michael; Geiser, Christian

2014-01-01

One of the key interests in the social sciences is the investigation of change and stability of a given attribute. Although numerous models have been proposed in the past for analyzing longitudinal data including multilevel and/or latent variable modeling approaches, only few modeling approaches have been developed for studying the construct validity in longitudinal multitrait-multimethod (MTMM) measurement designs. The aim of the present study was to extend the spectrum of current longitudinal modeling approaches for MTMM analysis. Specifically, a new longitudinal multilevel CFA-MTMM model for measurement designs with structurally different and interchangeable methods (called Latent-State-Combination-Of-Methods model, LS-COM) is presented. Interchangeable methods are methods that are randomly sampled from a set of equivalent methods (e.g., multiple student ratings for teaching quality), whereas structurally different methods are methods that cannot be easily replaced by one another (e.g., teacher, self-ratings, principle ratings). Results of a simulation study indicate that the parameters and standard errors in the LS-COM model are well recovered even in conditions with only five observations per estimated model parameter. The advantages and limitations of the LS-COM model relative to other longitudinal MTMM modeling approaches are discussed. PMID:24860515

Determining the Interstellar Wind Longitudinal Inflow Evolution Using Pickup Ions in the Helium Focusing Cone

NASA Astrophysics Data System (ADS)

Spitzer, S. A.; Gilbert, J. A.; Lepri, S. T.

2017-12-01

We propose to determine the longitudinal inflow direction of the local interstellar medium through the Heliosphere. This longitudinal inflow direction directly correlates to the longitudinal direction of the helium focusing cone with respect to the Sun. We can calculate this direction by finding the He+ pickup ion density peak as mass spectrometers such as ACE/SWICS, Wind/STICS, and Helios/Micrometeoroid Detector and Analyzer pass through the focusing cone. Mapping from the location of this density peak to the Sun, around which the helium is focused, will directly yield the desired longitudinal direction. We will find this direction for each year since the first measurements in the 1970s through the present and thereby analyze its evolution over time. This poster outlines our proposed method and initial results.

A Bayesian Approach for Analyzing Longitudinal Structural Equation Models

ERIC Educational Resources Information Center

Song, Xin-Yuan; Lu, Zhao-Hua; Hser, Yih-Ing; Lee, Sik-Yum

2011-01-01

This article considers a Bayesian approach for analyzing a longitudinal 2-level nonlinear structural equation model with covariates, and mixed continuous and ordered categorical variables. The first-level model is formulated for measures taken at each time point nested within individuals for investigating their characteristics that are dynamically…

Changes in Performance in a Management by Objectives Program

ERIC Educational Resources Information Center

Ivancevich, John M.

1974-01-01

Reports on empirically-based longitudinal study of performance in a manufacturing company that uses management by objectives. The performance of the subordinates of 181 MBO-involved supervisors in the production and marketing departments is analyzed. Time lag, reinforcement, and sustaining improvements in performance are considered and analyzed.…

Semantic Bias in the Acquisition of Relative Clauses in Japanese

ERIC Educational Resources Information Center

Ozeki, Hiromi; Shirai, Yasuhiro

2010-01-01

This study analyzes the acquisition of relative clauses in Japanese to determine the semantic and functional characteristics of children's relative clauses in spontaneous speech. Longitudinal data from five Japanese children are analyzed and compared with English data (Diessel & Tomasello, 2000). The results show that the relative clauses produced…

Longitudinal Fracture Analysis of a Two-Dimensional Functionally Graded Beam

NASA Astrophysics Data System (ADS)

Rizov, V.

2017-11-01

Longitudinal fracture in a two-dimensional functionally graded beam is analyzed. The modulus of elasticity varies continuously in the beam cross-section. The beam is clamped in its right-hand end. The external loading consists of one longitudinal force applied at the free end of the lower crack arm. The longitudinal crack is located in the beam mid-plane. The fracture is studied in terms of the strain energy release rate. The solution derived is used to elucidate the effects of material gradients along the height as well as along the width of the beam cross-section on the fracture behaviour. The results obtained indicate that the fracture in two-dimensional functionally graded beams can be regulated efficiently by employing appropriate material gradients.

Analyzing Longitudinal Data with Multilevel Models: An Example with Individuals Living with Lower Extremity Intra-articular Fractures

PubMed Central

Kwok, Oi-Man; Underhill, Andrea T.; Berry, Jack W.; Luo, Wen; Elliott, Timothy R.; Yoon, Myeongsun

2008-01-01

The use and quality of longitudinal research designs has increased over the past two decades, and new approaches for analyzing longitudinal data, including multi-level modeling (MLM) and latent growth modeling (LGM), have been developed. The purpose of this paper is to demonstrate the use of MLM and its advantages in analyzing longitudinal data. Data from a sample of individuals with intra-articular fractures of the lower extremity from the University of Alabama at Birmingham’s Injury Control Research Center is analyzed using both SAS PROC MIXED and SPSS MIXED. We start our presentation with a discussion of data preparation for MLM analyses. We then provide example analyses of different growth models, including a simple linear growth model and a model with a time-invariant covariate, with interpretation for all the parameters in the models. More complicated growth models with different between- and within-individual covariance structures and nonlinear models are discussed. Finally, information related to MLM analysis such as online resources is provided at the end of the paper. PMID:19649151

Analyzing AQP Data to Improve Electronic Flight Bag (EFB) Operations and Training

NASA Technical Reports Server (NTRS)

Seamster, Thomas L.; Kanki, Barbara

2010-01-01

Key points include: Initiate data collection and analysis early in the implementation process. Use data to identify procedural and training refinements. Use a de-identified system to analyze longitudinal data. Use longitudinal I/E data to improve their standardization. Identify above average pilots and crews and use their performance to specify best practices. Analyze below average crew performance data to isolate problems with the training, evaluator standardization and pilot proficiency.

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.

A Semiparametric Approach to Simultaneous Covariance Estimation for Bivariate Sparse Longitudinal Data

PubMed Central

Das, Kiranmoy; Daniels, Michael J.

2014-01-01

Summary Estimation of the covariance structure for irregular sparse longitudinal data has been studied by many authors in recent years but typically using fully parametric specifications. In addition, when data are collected from several groups over time, it is known that assuming the same or completely different covariance matrices over groups can lead to loss of efficiency and/or bias. Nonparametric approaches have been proposed for estimating the covariance matrix for regular univariate longitudinal data by sharing information across the groups under study. For the irregular case, with longitudinal measurements that are bivariate or multivariate, modeling becomes more difficult. In this article, to model bivariate sparse longitudinal data from several groups, we propose a flexible covariance structure via a novel matrix stick-breaking process for the residual covariance structure and a Dirichlet process mixture of normals for the random effects. Simulation studies are performed to investigate the effectiveness of the proposed approach over more traditional approaches. We also analyze a subset of Framingham Heart Study data to examine how the blood pressure trajectories and covariance structures differ for the patients from different BMI groups (high, medium and low) at baseline. PMID:24400941

Partially linear mixed-effects joint models for skewed and missing longitudinal competing risks outcomes.

PubMed

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.

Bayesian quantile regression-based partially linear mixed-effects joint models for longitudinal data with multiple features.

PubMed

Zhang, Hanze; Huang, Yangxin; Wang, Wei; Chen, Henian; Langland-Orban, Barbara

2017-01-01

In longitudinal AIDS studies, it is of interest to investigate the relationship between HIV viral load and CD4 cell counts, as well as the complicated time effect. Most of common models to analyze such complex longitudinal data are based on mean-regression, which fails to provide efficient estimates due to outliers and/or heavy tails. Quantile regression-based partially linear mixed-effects models, a special case of semiparametric models enjoying benefits of both parametric and nonparametric models, have the flexibility to monitor the viral dynamics nonparametrically and detect the varying CD4 effects parametrically at different quantiles of viral load. Meanwhile, it is critical to consider various data features of repeated measurements, including left-censoring due to a limit of detection, covariate measurement error, and asymmetric distribution. In this research, we first establish a Bayesian joint models that accounts for all these data features simultaneously in the framework of quantile regression-based partially linear mixed-effects models. The proposed models are applied to analyze the Multicenter AIDS Cohort Study (MACS) data. Simulation studies are also conducted to assess the performance of the proposed methods under different scenarios.

Ultrasonic input-output for transmitting and receiving longitudinal transducers coupled to same face of isotropic elastic plate

NASA Technical Reports Server (NTRS)

Williams, J. H., Jr.; Karagulle, H.; Lee, S. S.

1982-01-01

The quantitative understanding of ultrasonic nondestructive evaluation parameters such as the stress wave factor were studied. Ultrasonic input/output characteristics for an isotropic elastic plate with transmitting and receiving longitudinal transducers coupled to the same face were analyzed. The asymptotic normal stress is calculated for an isotropic elastic half space subjected to a uniform harmonic normal stress applied to a circular region at the surface. The radiated stress waves are traced within the plate by considering wave reflections at the top and bottom faces. The output voltage amplitude of the receiving transducer is estimated by considering only longitudinal waves. Agreement is found between the output voltage wave packet amplitudes and times of arrival due to multiple reflections of the longitudinal waves.

Analysis of baseline, average, and longitudinally measured blood pressure data using linear mixed models.

PubMed

Hossain, Ahmed; Beyene, Joseph

2014-01-01

This article compares baseline, average, and longitudinal data analysis methods for identifying genetic variants in genome-wide association study using the Genetic Analysis Workshop 18 data. We apply methods that include (a) linear mixed models with baseline measures, (b) random intercept linear mixed models with mean measures outcome, and (c) random intercept linear mixed models with longitudinal measurements. In the linear mixed models, covariates are included as fixed effects, whereas relatedness among individuals is incorporated as the variance-covariance structure of the random effect for the individuals. The overall strategy of applying linear mixed models decorrelate the data is based on Aulchenko et al.'s GRAMMAR. By analyzing systolic and diastolic blood pressure, which are used separately as outcomes, we compare the 3 methods in identifying a known genetic variant that is associated with blood pressure from chromosome 3 and simulated phenotype data. We also analyze the real phenotype data to illustrate the methods. We conclude that the linear mixed model with longitudinal measurements of diastolic blood pressure is the most accurate at identifying the known single-nucleotide polymorphism among the methods, but linear mixed models with baseline measures perform best with systolic blood pressure as the outcome.

The relationship between physical activity, physical fitness and overweight in adolescents: a systematic review of studies published in or after 2000

PubMed Central

2013-01-01

Background Not only in adults but also in children and adolescents, obesity increases the risk for several health disorders. In turn, many factors including genetic variations and environmental influences (e.g. physical activity) increase the risk of obesity. For instance, 25 to 40 percent of people inherit a predisposition for a high body mass index (BMI). The purpose of this systematic review was to summarize current cross-sectional and longitudinal studies on physical activity, fitness and overweight in adolescents and to identify mediator and moderator effects by evaluating the interaction between these three parameters. Methods The electronic academic databases PubMed, SportDiscus, WEB OF KNOWLEDGE and Ovid were searched for studies on physical activity, fitness and overweight in adolescents aged 11 to 19 years (cross-sectional studies) and in adolescents up to 23 years old (longitudinal studies) published in English in or after 2000. Results Twelve cross-sectional and two longitudinal studies were included. Only four studies analyzed the interaction among physical activity, fitness and overweight in adolescents and reported inconsistent results. All other studies analyzed the relationship between either physical activity and overweight, or between fitness and overweight. Overweight—here including obesity—was inversely related to physical activity. Similarly, all studies reported inverse relations between physical fitness and overweight. Mediator and moderator effects were detected in the interrelationship of BMI, fitness and physical activity. Overall, a distinction of excessive body weight as cause or effect of low levels of physical activity and fitness is lacking. Conclusions The small number of studies on the interrelationship of BMI, fitness and physical activity emphasizes the need for longitudinal studies that would reveal 1) the causality between physical activity and overweight / fitness and overweight and 2) the causal interrelationships among overweight, physical activity and fitness. These results must be carefully interpreted given the lack of distinction between self-reported and objective physical activity and that studies analyzing the metabolic syndrome or cardiovascular disease were not considered. The importance of physical activity or fitness in predicting overweight remains unknown. PMID:23375072

Education does not slow cognitive decline with aging: 12-year evidence from the victoria longitudinal study.

PubMed

Zahodne, Laura B; Glymour, M Maria; Sparks, Catharine; Bontempo, Daniel; Dixon, Roger A; MacDonald, Stuart W S; Manly, Jennifer J

2011-11-01

Although the relationship between education and cognitive status is well-known, evidence regarding whether education moderates the trajectory of cognitive change in late life is conflicting. Early studies suggested that higher levels of education attenuate cognitive decline. More recent studies using improved longitudinal methods have not found that education moderates decline. Fewer studies have explored whether education exerts different effects on longitudinal changes within different cognitive domains. In the present study, we analyzed data from 1014 participants in the Victoria Longitudinal Study to examine the effects of education on composite scores reflecting verbal processing speed, working memory, verbal fluency, and verbal episodic memory. Using linear growth models adjusted for age at enrollment (range, 54-95 years) and gender, we found that years of education (range, 6-20 years) was strongly related to cognitive level in all domains, particularly verbal fluency. However, education was not related to rates of change over time for any cognitive domain. Results were similar in individuals older or younger than 70 at baseline, and when education was dichotomized to reflect high or low attainment. In this large longitudinal cohort, education was related to cognitive performance but unrelated to cognitive decline, supporting the hypothesis of passive cognitive reserve with aging.

Longitudinal multiple imputation approaches for body mass index or other variables with very low individual-level variability: the mibmi command in Stata.

PubMed

Kontopantelis, Evangelos; Parisi, Rosa; Springate, David A; Reeves, David

2017-01-13

In modern health care systems, the computerization of all aspects of clinical care has led to the development of large data repositories. For example, in the UK, large primary care databases hold millions of electronic medical records, with detailed information on diagnoses, treatments, outcomes and consultations. Careful analyses of these observational datasets of routinely collected data can complement evidence from clinical trials or even answer research questions that cannot been addressed in an experimental setting. However, 'missingness' is a common problem for routinely collected data, especially for biological parameters over time. Absence of complete data for the whole of a individual's study period is a potential bias risk and standard complete-case approaches may lead to biased estimates. However, the structure of the data values makes standard cross-sectional multiple-imputation approaches unsuitable. In this paper we propose and evaluate mibmi, a new command for cleaning and imputing longitudinal body mass index data. The regression-based data cleaning aspects of the algorithm can be useful when researchers analyze messy longitudinal data. Although the multiple imputation algorithm is computationally expensive, it performed similarly or even better to existing alternatives, when interpolating observations. The mibmi algorithm can be a useful tool for analyzing longitudinal body mass index data, or other longitudinal data with very low individual-level variability.

An advanced stochastic model for threshold crossing studies of rotor blade vibrations.

NASA Technical Reports Server (NTRS)

Gaonkar, G. H.; Hohenemser, K. H.

1972-01-01

A stochastic model to analyze turbulence-excited rotor blade vibrations, previously described by Gaonkar et al. (1971), is generalized to include nonuniformity of the atmospheric turbulence velocity across the rotor disk in the longitudinal direction. The results of the presented analysis suggest that the nonuniformity of the vertical turbulence over the rotor disk is of little influence on the random blade flapping response, at least as far as longitudinal nonuniformity is concerned.

A joint modeling and estimation method for multivariate longitudinal data with mixed types of responses to analyze physical activity data generated by accelerometers.

PubMed

Li, Haocheng; Zhang, Yukun; Carroll, Raymond J; Keadle, Sarah Kozey; Sampson, Joshua N; Matthews, Charles E

2017-11-10

A mixed effect model is proposed to jointly analyze multivariate longitudinal data with continuous, proportion, count, and binary responses. The association of the variables is modeled through the correlation of random effects. We use a quasi-likelihood type approximation for nonlinear variables and transform the proposed model into a multivariate linear mixed model framework for estimation and inference. Via an extension to the EM approach, an efficient algorithm is developed to fit the model. The method is applied to physical activity data, which uses a wearable accelerometer device to measure daily movement and energy expenditure information. Our approach is also evaluated by a simulation study. Copyright © 2017 John Wiley & Sons, Ltd.

Probing longitudinal modes evolution of a InGaN green laser diode

NASA Astrophysics Data System (ADS)

Chen, Yi-Hsi; Lin, Wei-Chen; Chen, Hong-Zui; Shy, Jow-Tsong; Chui, Hsiang-Chen

2018-06-01

This study aims to investigate the longitudinal mode evolution of a InGaN green laser diode. A spectrometer with a 3-pm resolution was employed to obtain the emission spectra of a green laser diode, at a wavelength of around 520 nm, as a function of applied current and temperature. The spectral behavior of the laser modes with applied current was investigated. Right above the lasing threshold, the green diode laser emitted single longitudinal mode output. With increasing applied current, the number of the longitudinal modes increased. Up to ten lasing modes oscillated within the entire gain profile when the applied currents were tuned to 2.2Ith. Subsequently, a multi-Lorentzian profile model was adopted to analyze the spectra and observe how the modes evolved with temperature and applied current.

Joint model-based clustering of nonlinear longitudinal trajectories and associated time-to-event data analysis, linked by latent class membership: with application to AIDS clinical studies.

PubMed

Huang, Yangxin; Lu, Xiaosun; Chen, Jiaqing; Liang, Juan; Zangmeister, Miriam

2017-10-27

Longitudinal and time-to-event data are often observed together. Finite mixture models are currently used to analyze nonlinear heterogeneous longitudinal data, which, by releasing the homogeneity restriction of nonlinear mixed-effects (NLME) models, can cluster individuals into one of the pre-specified classes with class membership probabilities. This clustering may have clinical significance, and be associated with clinically important time-to-event data. This article develops a joint modeling approach to a finite mixture of NLME models for longitudinal data and proportional hazard Cox model for time-to-event data, linked by individual latent class indicators, under a Bayesian framework. The proposed joint models and method are applied to a real AIDS clinical trial data set, followed by simulation studies to assess the performance of the proposed joint model and a naive two-step model, in which finite mixture model and Cox model are fitted separately.

Follow Through Pupil Achievement Characteristics in Philadelphia Quasi-Longitudinal Data 1975-1976 and 1976-1977. Report #7870. Appendices Volume.

ERIC Educational Resources Information Center

McNamara, Thomas

Quasi-longitudinal data on student achievement, drawn from a computerized file on about 50,000 children, essentially consist of cross-sectional performance data analyzed in terms of length of program exposure while allowing for analysis of post-program performance on the basis of program exposure. The data are also analyzed according to the major…

Application of pattern mixture models to address missing data in longitudinal data analysis using SPSS.

PubMed

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.

Developing longitudinal qualitative designs: lessons learned and recommendations for health services research.

PubMed

Calman, Lynn; Brunton, Lisa; Molassiotis, Alex

2013-02-06

Longitudinal qualitative methods are becoming increasingly used in the health service research, but the method and challenges particular to health care settings are not well described in the literature.We reflect on the strategies used in a longitudinal qualitative study to explore the experience of symptoms in cancer patients and their carers, following participants from diagnosis for twelve months; we highlight ethical, practical, theoretical and methodological issues that need to be considered and addressed from the outset of a longitudinal qualitative study. Key considerations in undertaking longitudinal qualitative projects in health research, include the use of theory, utilizing multiple methods of analysis and giving consideration to the practical and ethical issues at an early stage. These can include issues of time and timing; data collection processes; changing the topic guide over time; recruitment considerations; retention of staff; issues around confidentiality; effects of project on staff and patients, and analyzing data within and across time. As longitudinal qualitative methods are becoming increasingly used in health services research, the methodological and practical challenges particular to health care settings need more robust approaches and conceptual improvement. We provide recommendations for the use of such designs. We have a particular focus on cancer patients, so this paper will have particular relevance for researchers interested in chronic and life limiting conditions.

The Predictive Validity of Four Intelligence Tests for School Grades: A Small Sample Longitudinal Study

PubMed Central

Gygi, Jasmin T.; Hagmann-von Arx, Priska; Schweizer, Florine; Grob, Alexander

2017-01-01

Intelligence is considered the strongest single predictor of scholastic achievement. However, little is known regarding the predictive validity of well-established intelligence tests for school grades. We analyzed the predictive validity of four widely used intelligence tests in German-speaking countries: The Intelligence and Development Scales (IDS), the Reynolds Intellectual Assessment Scales (RIAS), the Snijders-Oomen Nonverbal Intelligence Test (SON-R 6-40), and the Wechsler Intelligence Scale for Children (WISC-IV), which were individually administered to 103 children (Mage = 9.17 years) enrolled in regular school. School grades were collected longitudinally after 3 years (averaged school grades, mathematics, and language) and were available for 54 children (Mage = 11.77 years). All four tests significantly predicted averaged school grades. Furthermore, the IDS and the RIAS predicted both mathematics and language, while the SON-R 6-40 predicted mathematics. The WISC-IV showed no significant association with longitudinal scholastic achievement when mathematics and language were analyzed separately. The results revealed the predictive validity of currently used intelligence tests for longitudinal scholastic achievement in German-speaking countries and support their use in psychological practice, in particular for predicting averaged school grades. However, this conclusion has to be considered as preliminary due to the small sample of children observed. PMID:28348543

NATURAL ATTENUATION OF MTBE

EPA Science Inventory

For the case studies, the MTBE, TBA, and BTEX plume will be studied in a longitudinal transect along the center-line of the plume, and at least two transects perpendicular to ground water flow. Water samples will be analyzed for the concentration of MTBE, TBA, BTEX, methane, sulf...

Event History Data and Survey Recall. An Analysis of the Longitudinal Survey of Youth 1979 Recall Experiment.

ERIC Educational Resources Information Center

Pierret, Charles R.

2001-01-01

To test the effect of less-frequent interviews on data quality in longitudinal surveys, event history data from the National Longitudinal Survey of Youth 1979 regarding welfare and employment were analyzed. Due to the longer recall period, respondents failed to report short spells of welfare, employment, and unemployment. (SK)

Longitudinal Trajectories of Perceived Body Weight: Adolescence to Early Adulthood

ERIC Educational Resources Information Center

Seo, Dong-Chul; Li, Kaigang

2012-01-01

Objective: To examine longitudinal trajectories of perceived weight from adolescence to early adulthood by gender. Methods: We analyzed 9 waves (1997-2005) of data from the National Longitudinal Survey of Youth (N = 8302) using Mplus. Results: Perceived overweight increased over time among girls and did not level off until 23 years of age. Blacks…

Patterns of Entrepreneurial Career Development: An Optimal Matching Analysis Approach

ERIC Educational Resources Information Center

Zacher, Hannes; Biemann, Torsten; Gielnik, Michael M.; Frese, Michael

2012-01-01

Longitudinal studies of entrepreneurial career development are rare, and current knowledge of self-employment patterns and their relationships with individual difference characteristics is limited. In this study, the authors analyzed employment data from a subsample of 514 participants from the German Socio-Economic Panel study (1984-2008).…

Experimental research on the stability and the multilongitudinal mode interference of bidirectional outputs of LD-pumped solid state ring laser

NASA Astrophysics Data System (ADS)

Wan, Shunping; Tian, Qian; Sun, Liqun; Yao, Minyan; Mao, Xianhui; Qiu, Hongyun

2004-05-01

This paper reports an experimental research on the stability of bidirectional outputs and multi-longitudinal mode interference of laser diode end-pumped Nd:YVO4 solid-state ring laser (DPSSL). The bidirectional, multi-longitudinal and TEM00 mode continuous wave outputs are obtained and the output powers are measured and their stabilities are analyzed respectively. The spectral characteristic of the outputs is measured. The interfering pattern of the bidirectional longitudinal mode outputs is obtained and analyzed in the condition of the ring cavity with rotation velocity. The movement of the interfering fringe of the multi-longitudinal modes is very sensitive to the deformation of the setup base and the fluctuation of the intracavity air, but is stationary or randomly dithers when the stage is rotating.

Analysis of factors associated with cracked teeth.

PubMed

Seo, Deog-Gyu; Yi, Young-Ah; Shin, Su-Jung; Park, Jeong-Won

2012-03-01

The purpose of this study was to analyze the characteristics, distribution, and associated factors of longitudinal fractured teeth according to the well-defined criteria of the American Association of Endodontists (AAE). One hundred seven teeth with longitudinal fracture from 103 patients were diagnosed and analyzed. The patients' signs, symptoms, age, and sex were noted as well as the tooth number, dental arch, filling materials, size/classification of restoration, crack direction, pulp vitality, whether the patient had undergone endodontic treatment, bite test results, percussion test results, wear facet, and periodontal pocket depth. Eighty-seven teeth were diagnosed with a cracked tooth (81.3%), 14 were diagnosed with vertical root fracture (VRF, 13.1%), 4 had a split tooth (3.7%), and 2 had a fractured cusp (1.9%); 82.2% showed a sensitive reaction on the bite test. Longitudinal tooth fractures were observed most frequently in patient in their 40s. The upper first molar (28.0%) was most frequently cracked, followed by the lower first molar (25.2%), the lower second molar (20.6%), and the upper second molar (16.8%). Most longitudinal tooth fractures (72.0%) occurred mainly in restored teeth, whereas only 28.0% were found in intact teeth. Compared with resin (4.7%) or porcelain (0.9%), the use of nonbonded inlay restoration materials such as gold (20.5%) or amalgam (18.7%) increased the occurrence of longitudinal tooth fractures. Out of 107 of longitudinal fractured teeth, 33 (30.8%) were treated endodontically and 74 (69.2%) were not. VRF was associated with endodontic treatment. The bite test is most reliable for reproducing symptoms. The combined use of various examination methods is recommended for detecting cracks and minutely inspecting all directions of a tooth. Copyright © 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

The Myth of Peer Influence in Adolescent Smoking Initiation

ERIC Educational Resources Information Center

Arnett, Jeffrey Jensen

2007-01-01

The widespread belief that peer influence is the primary cause of adolescent smoking initiation is examined and called into question. Correlational and longitudinal studies purporting to demonstrate peer influence are analyzed, and their limitations described. Qualitative interview studies of adolescent smoking initiation are presented as…

Analysis of radial and longitudinal field of plasma wakefield generated by a Laguerre-Gauss laser pulse

DOE Office of Scientific and Technical Information (OSTI.GOV)

Firouzjaei, Ali Shekari; Shokri, Babak

In the present paper, we study the wakes known as the donut wake which is generated by Laguerre-Gauss (LG) laser pulses. Effects of the special spatial profile of a LG pulse on the radial and longitudinal wakefields are presented via an analytical model in a weakly non-linear regime in two dimensions. Different aspects of the donut-shaped wakefields have been analyzed and compared with Gaussian-driven wakes. There is also some discussion about the accelerating-focusing phase of the donut wake. Variations of longitudinal and radial wakes with laser amplitude, pulse length, and pulse spot size have been presented and discussed. Finally, wemore » present the optimum pulse duration for such wakes.« less

Standard deviation of vertical two-point longitudinal velocity differences in the atmospheric boundary layer.

NASA Technical Reports Server (NTRS)

Fichtl, G. H.

1971-01-01

Statistical estimates of wind shear in the planetary boundary layer are important in the design of V/STOL aircraft, and for the design of the Space Shuttle. The data analyzed in this study consist of eleven sets of longitudinal turbulent velocity fluctuation time histories digitized at 0.2 sec intervals with approximately 18,000 data points per time history. The longitudinal velocity fluctuations were calculated with horizontal wind and direction data collected at the 18-, 30-, 60-, 90-, 120-, and 150-m levels. The data obtained confirm the result that Eulerian time spectra transformed to wave-number spectra with Taylor's frozen eddy hypothesis possess inertial-like behavior at wave-numbers well out of the inertial subrange.

A comparison of three random effects approaches to analyze repeated bounded outcome scores with an application in a stroke revalidation study.

PubMed

Molas, Marek; Lesaffre, Emmanuel

2008-12-30

Discrete bounded outcome scores (BOS), i.e. discrete measurements that are restricted on a finite interval, often occur in practice. Examples are compliance measures, quality of life measures, etc. In this paper we examine three related random effects approaches to analyze longitudinal studies with a BOS as response: (1) a linear mixed effects (LM) model applied to a logistic transformed modified BOS; (2) a model assuming that the discrete BOS is a coarsened version of a latent random variable, which after a logistic-normal transformation, satisfies an LM model; and (3) a random effects probit model. We consider also the extension whereby the variability of the BOS is allowed to depend on covariates. The methods are contrasted using a simulation study and on a longitudinal project, which documents stroke rehabilitation in four European countries using measures of motor and functional recovery. Copyright 2008 John Wiley & Sons, Ltd.

Two-Year Diagnostic Stability in Early-Onset First-Episode Psychosis

ERIC Educational Resources Information Center

Castro-Fornieles, Josefina; Baeza, Immaculada; de la Serna, Elena; Gonzalez-Pinto, Ana; Parellada, Mara; Graell, Montserrat; Moreno, Dolores; Otero, Soraya; Arango, Celso

2011-01-01

Background: Only one study has used a prospective method to analyze the diagnostic stability of first psychotic episodes in children and adolescents. The Child and Adolescent First-Episode Psychosis Study (CAFEPS) is a 2-year, prospective longitudinal study of early-onset first episodes of psychosis (EO-FEP). Aim: To describe diagnostic stability…

Challenging Inquiry and Building Community: Analyzing ESL and Bilingual Teachers' Narratives

ERIC Educational Resources Information Center

Musanti, Sandra I.

2017-01-01

The study explores English as a second language (ESL) and bilingual teachers' narratives within a learning community as they collectively engage in reflecting on practices to more effectively support English learners. This longitudinal qualitative study integrates narrative inquiry approach and critical incident methodology. Participants were…

Adolescent Ethnolinguistic Stability and Change: A Longitudinal Study

ERIC Educational Resources Information Center

Kohn, Mary Elizabeth

2013-01-01

Most sociolinguistic studies rely on apparent time, cross-sectional methods to analyze language change. On the basis of apparent time data, sociolinguists have hypothesized that cultural processes of lifespan change create predictable cycles of linguistic behavior in which adolescents lead in the use of vernacular variants and advance sound change…

Structure and Stress: Trajectories of Depressive Symptoms across Adolescence and Young Adulthood

ERIC Educational Resources Information Center

Adkins, Daniel E.; Wang, Victor; Dupre, Matthew E.; van den Oord, Edwin J. C. G.; Elder, Glen H., Jr.

2009-01-01

Previous research into the social distribution of early life depression has yielded inconsistent results regarding the causes and course of subgroup depression disparities. This study examines the topic by analyzing National Longitudinal Study of Adolescent Health data, modeling gender and racial/ethnic differences in early life depression…

A Longitudinal Study of Psychological Differentiation In Nigerian Children.

ERIC Educational Resources Information Center

Jegede, R. Olukayode; Bamgboye, E. Afolabi

1983-01-01

Presents results of a three-year follow-up study of the development of psychological differentiation in Nigerian children. Human figure drawings made in 1974 and 1977 by 204 subjects aged 7 to 14 years were analyzed using Witkins Articulation of Body Concept scale and compared. (Author/RH)

School Violence and Student Achievement in Reading and Mathematics among Eighth Graders.

ERIC Educational Resources Information Center

Coleman, Beverly Eugene

This study analyzed base-year student data files from the 1988 National Education Longitudinal Study (NELS:88) cross-sectionally to identify relationships between school violence and student achievement in reading and mathematics. The analysis identified student behavior variables related to three measures of school violence: (1) personal…

Poorer Visual Acuity Is Associated with Declines in Cognitive Performance Across Multiple Cognitive Domains: The Maine-Syracuse Longitudinal Study.

PubMed

Dearborn, Peter J; Elias, Merrill F; Sullivan, Kevin J; Sullivan, Cara E; Robbins, Michael A

2018-06-21

Prior studies have found associations between visual acuity (VA) and cognitive function. However, these studies used a limited range of cognitive measures and did not control for cardiovascular disease risk factors (CVD-RFs) and baseline function. The primary objective of this study was to analyze the associations of VA and cognitive performance using a thorough neuropsychological test battery. This study used community-dwelling sample data across the sixth (2001-2006) and seventh (2006-2010) waves of the Maine-Syracuse Longitudinal Study (n=655). Wave 6 VA as measured by the Snellen Eye Test was the primary predictor of wave 6 and wave 7 Global cognitive performance, Visual-Spatial Organization and Memory, Verbal Episodic Memory, Working Memory, Scanning and Tracking, and Executive Function. Additionally, VA was used to predict longitudinal changes in wave 7 cognitive performance (wave 6 performance adjusted). We analyzed these relationships with multiple linear and logistic regression models adjusted for age, sex, education, ethnicity, depressive symptoms, physical function deficits in addition to CVD-RFs, chronic kidney disease, homocysteine, continuous systolic blood pressure, and hypertension status. Adjusted for demographic covariates and CVD-RFs, poorer VA was associated with concurrent and approximate 5-year declines in Global cognitive function, Visual-Spatial Organization and Memory, and Verbal Episodic Memory. VA may be used in combination with other screening measures to determine risk for cognitive decline. (JINS, 2018, 24, 1-9).

Long-term analysis of health status and preventive behavior in music students across an entire university program.

PubMed

Spahn, Claudia; Nusseck, Manfred; Zander, Mark

2014-03-01

The aim of this investigation was to analyze longitudinal data concerning physical and psychological health, playing-related problems, and preventive behavior among music students across their complete 4- to 5-year study period. In a longitudinal, observational study, we followed students during their university training and measured their psychological and physical health status and preventive behavior using standardized questionnaires at four different times. The data were in accordance with previous findings. They demonstrated three groups of health characteristics observed in beginners of music study: healthy students (cluster 1), students with preclinical symptoms (cluster 2), and students who are clinically symptomatic (cluster 3). In total, 64% of all students remained in the same cluster group during their whole university training. About 10% of the students showed considerable health problems and belonged to the third cluster group. The three clusters of health characteristics found in this longitudinal study with music students necessitate that prevention programs for musicians must be adapted to the target audience.

Long-term morphological developments of river channels separated by a longitudinal training wall

NASA Astrophysics Data System (ADS)

Le, T. B.; Crosato, A.; Uijttewaal, W. S. J.

2018-03-01

Rivers have been trained for centuries by channel narrowing and straightening. This caused important damages to their ecosystems, particularly around the bank areas. We analyze here the possibility to train rivers in a new way by subdividing their channel in main and ecological channel with a longitudinal training wall. The effectiveness of longitudinal training walls in achieving this goal and their long-term effects on the river morphology have not been thoroughly investigated yet. In particular, studies that assess the stability of the two parallel channels separated by the training wall are still lacking. This work studies the long-term morphological developments of river channels subdivided by a longitudinal training wall in the presence of steady alternate bars. This type of bars, common in alluvial rivers, alters the flow field and the sediment transport direction and might affect the stability of the bifurcating system. The work comprises both laboratory experiments and numerical simulations (Delft3D). The results show that a system of parallel channels divided by a longitudinal training wall has the tendency to become unstable. An important factor is found to be the location of the upstream termination of the longitudinal wall with respect to a neighboring steady bar. The relative widths of the two parallel channels separated by the wall and variable discharge do not substantially change the final evolution of the system.

What Happens to a Nursing Home Chain When Private Equity Takes Over? A Longitudinal Case Study.

PubMed

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."

A longitudinal study of the effects of dual-earner couples' utilization of family-friendly workplace supports on work and family outcomes.

PubMed

Hammer, Leslie B; Neal, Margaret B; Newsom, Jason T; Brockwood, Krista J; Colton, Cari L

2005-07-01

Little research exists on the effects of the utilization of workplace supports on work-family conflict and job satisfaction. With family systems theory as a framework, 2 waves of national survey data were collected from 234 couples (N = 468) caring for children and for aging parents. Data were analyzed with structural equation modeling techniques. Longitudinal results indicate that individuals' use of workplace supports was related to work-family conflict in the direction opposite to expectations and was related to job satisfaction in the direction consistent with expectations. Differential effects for wives versus husbands were found. In addition, couples' use of workplace supports was only minimally related to wives' outcomes. Results are discussed in terms of gender differences, family systems theory, and methodological and measurement issues related to the longitudinal study of utilization of workplace supports. Copyright 2005 APA, all rights reserved.

Quantification of right ventricular volumes and function by real time three-dimensional echocardiographic longitudinal axial plane method: validation in the clinical setting.

PubMed

Endo, Yuka; Maddukuri, Prasad V; Vieira, Marcelo L C; Pandian, Natesa G; Patel, Ayan R

2006-11-01

Measurement of right ventricular (RV) volumes and right ventricular ejection fraction (RVEF) by three-dimensional echocardiographic (3DE) short-axis disc summation method has been validated in multiple studies. However, in some patients, short-axis images are of insufficient quality for accurate tracing of the RV endocardial border. This study examined the accuracy of long-axis analysis in multiple planes (longitudinal axial plane method) for assessment of RV volumes and RVEF. 3DE images were analyzed in 40 subjects with a broad range of RV function. RV end-diastolic (RVEDV) and end-systolic volumes (RVESV) and RVEF were calculated by both short-axis disc summation method and longitudinal axial plane method. Excellent correlation was obtained between the two methods for RVEDV, RVESV, and RVEF (r = 0.99, 0.99, 0.94, respectively; P < 0.0001 for all comparisons). 3DE longitudinal-axis analysis is a promising technique for the evaluation of RV function, and may provide an alternative method of assessment in patients with suboptimal short-axis images.

Risky online behaviors among adolescents: Longitudinal relations among problematic Internet use, cyberbullying perpetration, and meeting strangers online.

PubMed

Gámez-Guadix, Manuel; Borrajo, Erika; Almendros, Carmen

2016-03-01

Background and aims This study aims to analyze the cross-sectional and longitudinal relationship between three major risky online behaviors during adolescence: problematic Internet use, cyberbullying perpetration, and meeting strangers online. An additional objective was to study the role of impulsivity-irresponsibility as a possible explanatory variable of the relationships between these risky online behaviors. Methods The study sample was 888 adolescents that completed self-report measures at time 1 and time 2 with an interval of 6 months. Results The findings showed a significant cross-sectional relationship between the risky online behaviors analyzed. At the longitudinal level, problematic Internet use at time 1 predicted an increase in the perpetration of cyberbullying and meeting strangers online at time 2. Furthermore, meeting strangers online increased the likelihood of cyberbullying perpetration at time 2. Finally, when impulsivity-irresponsibility was included in the model as an explanatory variable, the relationships previously found remained significant. Discussion These results extend traditional problem behavior theory during adolescence, also supporting a relationship between different risky behaviors in cyberspace. In addition, findings highlighted the role of problematic Internet use, which increased the chances of developing cyberbullying perpetration and meeting strangers online over time. However, the results suggest a limited role of impulsivity-irresponsibility as an explicative mechanism. Conclusions The findings suggest that various online risk activities ought to be addressed together when planning assessment, prevention and intervention efforts.

Study of spin dynamics and damping on the magnetic nanowire arrays with various nanowire widths

NASA Astrophysics Data System (ADS)

Cho, Jaehun; Fujii, Yuya; Konioshi, Katsunori; Yoon, Jungbum; Kim, Nam-Hui; Jung, Jinyong; Miwa, Shinji; Jung, Myung-Hwa; Suzuki, Yoshishige; You, Chun-Yeol

2016-07-01

We investigate the spin dynamics including Gilbert damping in the ferromagnetic nanowire arrays. We have measured the ferromagnetic resonance of ferromagnetic nanowire arrays using vector-network analyzer ferromagnetic resonance (VNA-FMR) and analyzed the results with the micromagnetic simulations. We find excellent agreement between the experimental VNA-FMR spectra and micromagnetic simulations result for various applied magnetic fields. We find that the same tendency of the demagnetization factor for longitudinal and transverse conditions, Nz (Ny) increases (decreases) as increasing the nanowire width in the micromagnetic simulations while Nx is almost zero value in transverse case. We also find that the Gilbert damping constant increases from 0.018 to 0.051 as the increasing nanowire width for the transverse case, while it is almost constant as 0.021 for the longitudinal case.

Personality Trait Development and Social Investment in Work

PubMed Central

Hudson, Nathan W.; Roberts, Brent W.; Lodi-Smith, Jennifer

2012-01-01

A longitudinal study of employed individuals was used to test the relationship between social investment at work—the act of cognitively and emotionally committing to one’s job—and longitudinal and cross-sectional personality trait development. Participants provided ratings of personality traits and social investment at work at two time-points, separated by approximately three years. Data were analyzed using latent change models. Cross-sectional results showed that extraversion, agreeableness, conscientiousness and emotional stability were related to social investment at work. Additionally, a positive association was found between longitudinal change in social investment in work and change in personality traits—especially conscientiousness. Finally, the correlated changes in social investment and personality traits were invariant across age groups, suggesting that personality traits remain malleable across the lifespan. PMID:22822278

Social Studies and Secondary Students' Political Attitudes toward Society and School: A Two-Year Longitudinal Study.

ERIC Educational Resources Information Center

Ehman, Lee H.

The effect of social studies instruction on students' attitudes toward school and society for two years is analyzed. The social studies variables examined for their influence on the trends across time for nine attitudes were the number of social studies semesters, the extent of controversial issues treatment, treatment of more than one side of…

Evaluation of longitudinal steroid profiles from male football players in UEFA competitions between 2008 and 2013.

PubMed

Baume, Norbert; Geyer, Hans; Vouillamoz, Marc; Grisdale, Richard; Earl, Mike; Aguilera, Rodrigo; Cowan, David A; Ericsson, Magnus; Gmeiner, Günter; Kwiatkowska, Dorota; Kioukia-Fougia, Nassia; Molina, Adeline; Ruivo, João; Segura, Jordi; Van Eenoo, Peter; Jan, Nicolas; Robinson, Neil; Saugy, Martial

2016-07-01

Testosterone and related compounds are the most recurrent doping substances. The steroid profile, consisting of the quantification of testosterone and its metabolites, has been described as the most significant biomarker to detect doping with pseudo-endogenous anabolic steroids. The steroidal module of the Athlete Biological Passport (ABP) was launched by the World Anti-Doping Agency (WADA) in 2014. To assess the value of introducing the module to its anti-doping programme, the Union of European Football Associations (UEFA) decided to analyze retrospectively the steroid profile data of 4195 urine samples, collected from 879 male football players and analyzed in 12 WADA-accredited laboratories between 2008 and mid-2013. This study focused on the evaluation of T/E ratios. The coefficient of variation (CV) and the adaptive model were the two statistical models used to study the longitudinal follow-up. A CV of 46% was determined to be the maximal natural intra-individual variation of the T/E when the sequence consisted of single data points analyzed in different laboratories. The adaptive model showed some profiles with an atypical T/E sequence and also enabled an estimate of the prevalence of external factors impacting the T/E sequences. Despite the limitations of this retrospective study, it clearly showed that the longitudinal and individual follow-up of the T/E biomarker of the players is a good tool for target testing in football. UEFA has therefore decided to implement the steroidal module of the ABP from the start of the next European football season in September 2015. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

Longitudinal and cross-sectional analyses of visual field progression in participants of the Ocular Hypertension Treatment Study.

PubMed

Artes, Paul H; Chauhan, Balwantray C; Keltner, John L; Cello, Kim E; Johnson, Chris A; Anderson, Douglas R; Gordon, Mae O; Kass, Michael A

2010-12-01

To assess agreement between longitudinal and cross-sectional analyses for determining visual field progression in data from the Ocular Hypertension Treatment Study. Visual field data from 3088 eyes of 1570 participants (median follow-up, 7 years) were analyzed. Longitudinal analyses were performed using change probability with total and pattern deviation, and cross-sectional analyses were performed using the glaucoma hemifield test, corrected pattern standard deviation, and mean deviation. The rates of mean deviation and general height change were compared to estimate the degree of diffuse loss in emerging glaucoma. Agreement on progression in longitudinal and cross-sectional analyses ranged from 50% to 61% and remained nearly constant across a wide range of criteria. In contrast, agreement on absence of progression ranged from 97.0% to 99.7%, being highest for the stricter criteria. Analyses of pattern deviation were more conservative than analyses of total deviation, with a 3 to 5 times lesser incidence of progression. Most participants developing field loss had both diffuse and focal changes. Despite considerable overall agreement, 40% to 50% of eyes identified as having progressed with either longitudinal or cross-sectional analyses were identified with only one of the analyses. Because diffuse change is part of early glaucomatous damage, pattern deviation analyses may underestimate progression in patients with ocular hypertension.

Predictive probability methods for interim monitoring in clinical trials with longitudinal outcomes.

PubMed

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.

Peer Victimization among Young Children with Disabilities: Early Risk and Protective Factors

ERIC Educational Resources Information Center

Son, Esther; Peterson, N. Andrew; Pottick, Kathleen J.; Zippay, Allison; Parish, Susan L.; Lohrmann, Sharon

2014-01-01

The purpose of this study was to examine the risk and protective factors of peer victimization among young children with disabilities. This study analyzed data from the Pre-Elementary Education Longitudinal Study (n =1,130) to test a path model that included child, family, and school characteristics at Year 1 and peer-relation difficulties and…

A Longitudinal Study of Cocaine Use among Juvenile Arrestees

ERIC Educational Resources Information Center

Dembo, Richard; Wareham, Jennifer; Schmeidler, James

2007-01-01

We report the results of latent growth model analyses examining the continuity of cocaine use among adolescents. This study examined a sample of 278 justice-involved juveniles completing at least one of three follow-up interviews as part of a National Institute on Drug Abuse funded study. Latent growth models were analyzed examining (1) changes in…

WWC Quick Review of the Article "School Recess and Group Classroom Behavior"

ERIC Educational Resources Information Center

What Works Clearinghouse, 2009

2009-01-01

This study examined whether providing daily recess to third graders improves their classroom behavior. The study analyzed a nationally representative sample of over 10,000 students enrolled in third grade during the 2001-2002 school year. Data were drawn from the Early Childhood Longitudinal Study, Kindergarten Class of 1998-1999. The authors…

The Skinny on Success: Body Mass, Gender and Occupational Standing across the Life Course

ERIC Educational Resources Information Center

Glass, Christy M.; Haas, Steven A.; Reither, Eric N.

2010-01-01

Several studies have analyzed the impact of obesity on occupational standing. This study extends previous research by estimating the influence of body mass on occupational attainment over three decades of the career using data from the Wisconsin Longitudinal Study. In a series of covariance structure analyses, we considered three mechanisms that…

When Money Really Matters: Tying Resources of Specific Programmatic and Instructional Elements to Student Academic Growth

ERIC Educational Resources Information Center

Goetz, Michael Eric

2012-01-01

This study explores the cost-effectiveness ratios associated with individual tutoring, intensive reading/language arts instruction, and a focus on core subject areas. Using the Early Childhood Longitudinal Study (ECLS-K) database, this study analyzes these programs using a three-level hierarchical linear model (HLM) with a nationally…

A longitudinal model for functional connectivity networks using resting-state fMRI.

PubMed

Hart, Brian; Cribben, Ivor; Fiecas, Mark

2018-06-04

Many neuroimaging studies collect functional magnetic resonance imaging (fMRI) data in a longitudinal manner. However, the current fMRI literature lacks a general framework for analyzing functional connectivity (FC) networks in fMRI data obtained from a longitudinal study. In this work, we build a novel longitudinal FC model using a variance components approach. First, for all subjects' visits, we account for the autocorrelation inherent in the fMRI time series data using a non-parametric technique. Second, we use a generalized least squares approach to estimate 1) the within-subject variance component shared across the population, 2) the baseline FC strength, and 3) the FC's longitudinal trend. Our novel method for longitudinal FC networks seeks to account for the within-subject dependence across multiple visits, the variability due to the subjects being sampled from a population, and the autocorrelation present in fMRI time series data, while restricting the number of parameters in order to make the method computationally feasible and stable. We develop a permutation testing procedure to draw valid inference on group differences in the baseline FC network and change in FC over longitudinal time between a set of patients and a comparable set of controls. To examine performance, we run a series of simulations and apply the model to longitudinal fMRI data collected from the Alzheimer's Disease Neuroimaging Initiative (ADNI) database. Overall, we found no difference in the global FC network between Alzheimer's disease patients and healthy controls, but did find differing local aging patterns in the FC between the left hippocampus and the posterior cingulate cortex. Copyright © 2018 Elsevier Inc. All rights reserved.

Change in Psychosocial Health Status Over 5 Years in Relation to Adults' Hearing Ability in Noise.

PubMed

Stam, Mariska; Smit, Jan H; Twisk, Jos W R; Lemke, Ulrike; Smits, Cas; Festen, Joost M; Kramer, Sophia E

The aim of this study was to establish the longitudinal relationship between hearing ability in noise and psychosocial health outcomes (i.e., loneliness, anxiety, depression, distress, and somatization) in adults aged 18 to 70 years. An additional objective was to determine whether a change in hearing ability in noise over a period of 5 years was associated with a change in psychosocial functioning. Subgroup effects for a range of factors were investigated. Longitudinal data of the web-based Netherlands Longitudinal Study on Hearing (NL-SH) (N = 508) were analyzed. The ability to recognize speech in noise (i.e., the speech-reception-threshold [SRTn]) was measured with an online digit triplet test at baseline and at 5-year follow-up. Psychosocial health status was assessed by online questionnaires. Multiple linear regression analyses and longitudinal statistical analyses (i.e., generalized estimating equations) were performed. Poorer SRTn was associated longitudinally with more feelings of emotional and social loneliness. For participants with a high educational level, the longitudinal association between SRTn and social loneliness was significant. Changes in hearing ability and loneliness appeared significantly associated only for specific subgroups: those with stable pattern of hearing aid nonuse (increased emotional and social loneliness), who entered matrimony (increased social loneliness), and low educational level (less emotional loneliness). No significant longitudinal associations were found between hearing ability and anxiety, depression, distress, or somatization. Hearing ability in noise was longitudinally associated with loneliness. Decline in hearing ability in noise was related to increase in loneliness for specific subgroups of participants. One of these subgroups included participants whose hearing deteriorated over 5 years, but who continued to report nonuse of hearing aids. This is an important and alarming finding that needs further investigation.

A comparison of longitudinal and transverse approaches to ultrasound-guided axillary vein cannulation by experienced operators.

PubMed

He, Yi-Zhou; Zhong, Ming; Wu, Wei; Song, Jie-Qiong; Zhu, Du-Ming

2017-04-01

The axillary vein is an easily accessible vessel that can be used for ultrasound-guided central vascular access and offers an alternative to the internal jugular and subclavian veins. The objective of this study was to identify which transducer orientation, longitudinal or transverse, is better for imaging the axillary vein with ultrasound. We analyzed 236 patients who had undergone central venous cannulation of axillary vein in this retrospective study. Patients were divided into two groups, the longitudinal approach group (n=120) and transverse approach group (n=116). Recorded the one-attempt success rate, operation time, arterial puncture rate and pneumothorax rate. We perform chest radiography to confirm pneumothorax on all patients. We compared the one-attempt success rate, operation time, arterial puncture rate and pneumothorax rate between the two groups. The two groups were comparable with clinical characters of patients. The overall success rates of the longitudinal group and the transverse group were both 100%. The rate of one-attempt success in the longitudinal approach group is higher than the transverse approach group (91.7% vs. 82.8%, P=0.040). The transverse approach group had shorter operation time than the longitudinal group (184.7±8.1 vs. 287.5±19.6 seconds, P=0.000). The two groups had lower postoperative complications. Arterial puncture occurred in 1 of 120 longitudinal and 2 of 116 transverse attempts and this difference was no significant (P=0.541). No pneumothorax occurred in the two groups. The longitudinal approach during ultrasound-guided axillary vein cannulation is associated with greater one-attempt success rate compared with the transverse approach by experienced operators. The transverse approach has shorter operation time. The two groups have lower postoperative complications and are comparable with pneumothorax and arterial puncture.

Infancy to Early Childhood: Genetic and Environmental Influences on Developmental Change.

ERIC Educational Resources Information Center

Emde, Robert N., Ed.; Hewitt, John K., Ed.

This book analyzes the MacArthur Longitudinal Twin Study, a collaborative study by leading developmental scientists and behavioral geneticists on the transition from infancy to early childhood. Part 1 of the book describes the twin method and procedures used and introduces the analytic strategies. Parts 2 through 4 present results related to…

Science, Technology, Engineering, and Mathematics (STEM) Participation among College Students with an Autism Spectrum Disorder

ERIC Educational Resources Information Center

Wei, Xin; Yu, Jennifer W.; Shattuck, Paul; McCracken, Mary; Blackorby, Jose

2013-01-01

Little research has examined the popular belief that individuals with an autism spectrum disorder (ASD) are more likely than the general population to gravitate toward science, technology, engineering, and mathematics (STEM) fields. This study analyzed data from the National Longitudinal Transition Study-2, a nationally representative sample of…

A Retest of Two HIV Disclosure Theories: The Women's Story

ERIC Educational Resources Information Center

Serovich, Julianne M.; Lim, Ji-Young; Mason, Tina L.

2008-01-01

The purpose of this study was to evaluate the applicability of two theories of HIV disclosure previously tested with men. Participants included 125 HIV-positive women enrolled in a larger, longitudinal study of HIV disclosure and mental health. Structural equation modeling was used to analyze the proposed theoretical models. The disease…

Early Childhood Family Structure and Mother-Child Interactions: Variation by Race and Ethnicity

ERIC Educational Resources Information Center

Gibson-Davis, Christina M.; Gassman-Pines, Anna

2010-01-01

With data from the Early Childhood Longitudinal Study-Birth Cohort (n = 6,449), a nationally representative sample of births in 2001, we used hierarchical linear modeling to analyze differences in observed interactions between married, cohabiting, never-married, and divorced mothers and their children. In contrast to previous studies, we…

Postschool Goals and Transition Services for Students with Learning Disabilities

ERIC Educational Resources Information Center

Daviso, Alfred W.; Denney, Stephen C.; Baer, Robert M.; Flexer, Robert

2011-01-01

This article describes the initial findings for students with learning disabilities from the first year of The Ohio Longitudinal Transition Study (OLTS). The study included 416 participants with learning disabilities who were exiting high school. Data from an in-school survey were analyzed by sample demographics (e.g. school setting, school type,…

The Role of Facilitators in Project Action Learning Implementation

ERIC Educational Resources Information Center

Cao, Rui; Chuah, Kong Bieng; Chao, Yiu Chung; Kwong, Kar Fai; Law, Mo Yin

2012-01-01

Purpose: This paper addresses the importance of a more proactive role of organizational learning (OL) facilitators, learning motivation reinforcer, through a two-part longitudinal study in a case company. The first part of this study aims to investigate and analyze some unexpected challenges in the project action learning-driven (PAL) OL…

The Effects of English Language Proficiency and Curricular Pathways: Latina/os' Mathematics Achievement in Secondary Schools

ERIC Educational Resources Information Center

Mosqueda, Eduardo; Maldonado, Saul I.

2013-01-01

This study analyzes nationally-representative quantitative data from the first (2002) and second (2004) waves of the Educational Longitudinal Study to examine the relationship between Latina/o secondary school students' degree of English-language proficiency (ELP), mathematics course-taking measures, and 12th grade mathematics achievement.…

Student Employment and Persistence: Evidence of Effect Heterogeneity of Student Employment on College Dropout

ERIC Educational Resources Information Center

Choi, Yool

2018-01-01

This study explores how student employment affects college persistence and how these effects differ by individual likelihood of participating in student employment. I analyze data from the National Longitudinal Survey of Youth 1997 using propensity score matching and stratification-multilevel analysis. This study finds that engaging in intense…

Post-MBA Industry Shifts: An Investigation of Career, Educational and Demographic Factors

ERIC Educational Resources Information Center

Hwang, Alvin; Bento, Regina; Arbaugh, J. B.

2011-01-01

Purpose: The purpose of this study is to examine factors that predict industry-level career change among MBA graduates. Design/methodology/approach: The study analyzed longitudinal data from the Management Education Research Institute (MERI)'s Global MBA Graduate Survey Dataset and MBA Alumni Perspectives Survey Datasets, using principal component…

Community Context, Social Integration into Family, and Youth Violence

ERIC Educational Resources Information Center

Knoester, Chris; Haynie, Dana L.

2005-01-01

The purpose of this study is to analyze the extent to which neighborhood-level family structure and feelings of family integration are associated with acts of violence among 16,910 adolescents from the National Longitudinal Study of Adolescent Health. The results from our hierarchical linear models indicate that adolescents who live in…

Catholic Schools and Bad Behavior. NBER Working Paper.

ERIC Educational Resources Information Center

Mocan, H. Naci; Scafidi, Benjamin; Tekin, Erdal

This study used data from Wave 1 of the National Longitudinal Study of Adolescent Health to analyze the impact of Catholic school attendance on the likelihood of teens participating in 13 risky behaviors (e.g., using or selling drugs, committing property crime, having sex, engaging in gang-related fights, attempting suicide, and running away from…

Science, Technology, Engineering, and Mathematics (STEM) Participation among College Students with an Autism Spectrum Disorder

ERIC Educational Resources Information Center

Wei, Xin; Christiano, Elizabeth R.; Yu, Jennifer W.; Blackorby, Jose; Shattuck, Paul; Newman, Lynn A.

2014-01-01

Little research has examined the popular belief that individuals with an autism spectrum disorder (ASD) are more likely than the general population to gravitate toward science, technology, engineering, and mathematics (STEM) fields. This study analyzed data from the National Longitudinal Transition Study-2, a nationally representative sample of…

Blurring Boundaries? Linking Technology Use, Spillover, Individual Distress, and Family Satisfaction

ERIC Educational Resources Information Center

Chesley, Noelle

2005-01-01

Information technology is entrenched in everyday life; yet, scholars have not firmly established whether this use blesses or vexes individuals and their families. This study analyzes longitudinal data (N = 1,367) from the Cornell Couples and Careers Study to assess whether increases in spillover explain changes in distress and family satisfaction…

Training Habits and Injury Experience in Distance Runners: Age- and Sex-Related Factors.

ERIC Educational Resources Information Center

Walter, Stephen D.

1988-01-01

An 80-item questionnaire was used to study variations by age and sex in the training habits and injury experience of 688 adult distance runners. The results are analyzed according to these variables. Methodology is discussed. This is part of a longitudinal study of 1,700 runners. (Author/JL)

Possible Insomnia Predicts Some Risky Behaviors among Adolescents when Controlling for Depressive Symptoms

ERIC Educational Resources Information Center

Catrett, Christina D.; Gaultney, Jane F.

2009-01-01

This study investigated whether previously reported links between sleep and risk taking among adolescents (E. M. O'Brien & J. A. Mindell, 2005) are associated--concurrently, longitudinally, or both--with sleep or underlying depression. The present study analyzed data from a nationally representative sample of 4,353 adolescents in the United…

Longitudinal analysis of the effect of academic failure tolerance on academic achievement fluctuation in medical school students.

PubMed

Chae, Su Jin; Kim, Miran; Chang, Ki Hong

2016-03-01

Academic failure tolerance (AFT) is one of the important psychological concepts in education, but its applications in medical education are rare. Thus, the purpose of this study was to investigate the effect of academic failure tolerance on academic achievement fluctuation among medical school students using a longitudinal research design. The subjects were 43 medical students who responded to the AFT test. This study analyzed the longitudinal data of achievement scores up to the 2nd academic year (2012-2013) among students who were divided into academic achievement improvement and decline groups. Comparing the improvement and decline groups' mean academic achievement fluctuation scores demonstrated that behavior and preferred task difficulty showed high scores whereas feeling scores were lower in the improvement group (p<0.05). In the improvement group, despite the higher negative feeling scores during academic failure, the students favored the more difficult subjects and were more assiduous in their studies. This will form an important basis for enhancing academic achievement among medical students.

The re-identification risk of Canadians from longitudinal demographics

PubMed Central

2011-01-01

Background The public is less willing to allow their personal health information to be disclosed for research purposes if they do not trust researchers and how researchers manage their data. However, the public is more comfortable with their data being used for research if the risk of re-identification is low. There are few studies on the risk of re-identification of Canadians from their basic demographics, and no studies on their risk from their longitudinal data. Our objective was to estimate the risk of re-identification from the basic cross-sectional and longitudinal demographics of Canadians. Methods Uniqueness is a common measure of re-identification risk. Demographic data on a 25% random sample of the population of Montreal were analyzed to estimate population uniqueness on postal code, date of birth, and gender as well as their generalizations, for periods ranging from 1 year to 11 years. Results Almost 98% of the population was unique on full postal code, date of birth and gender: these three variables are effectively a unique identifier for Montrealers. Uniqueness increased for longitudinal data. Considerable generalization was required to reach acceptably low uniqueness levels, especially for longitudinal data. Detailed guidelines and disclosure policies on how to ensure that the re-identification risk is low are provided. Conclusions A large percentage of Montreal residents are unique on basic demographics. For non-longitudinal data sets, the three character postal code, gender, and month/year of birth represent sufficiently low re-identification risk. Data custodians need to generalize their demographic information further for longitudinal data sets. PMID:21696636

Three Critical Tasks America's Disadvantaged Face on Their Path to College.

ERIC Educational Resources Information Center

Cabrera, Alberto F.; La Nasa, Steven M.

2000-01-01

Using data from the National Educational Longitudinal Study of 1988, examines the wide disparity of college-choice activities between socioeconomic groups. In order to highlight this disparity, analyzes three tasks that all students must complete on their path to college. (Author/EV)

Can Parents Influence Children's Mathematics Achievement and Persistence in STEM Careers?

ERIC Educational Resources Information Center

Ing, Marsha

2014-01-01

This study explores the relationship between parental motivational practices, Children's mathematics achievement trajectories, and persistence in science, technology, engineering, and mathematics (STEM) careers. Nationally representative longitudinal survey data were analyzed using latent growth curve analysis. Findings indicate that…

PASSIVE SMOKING AND HEIGHT GROWTH OF PREADOLESCENT CHILDREN

EPA Science Inventory

The attained height and height growth of 9273 children participating in a longitudinal study of the health effects of air pollutants were analyzed to assess the association between passive exposure to cigarette smoke and physical growth between 6 and 11 years of age. Children wer...

Psychophysiological effects of aging : developing a functional age index for pilots. I., A survey of the pertinent literature.

DOT National Transportation Integrated Search

1977-01-01

This report gives a survey about selected material concerning age and aviation-related psychophysiological functions. The author analyzes the results obtained by many investigators from longitudinal and cross-sectional studies that may be useful for ...

Beyond Justice: What Makes an Indigenous Justice Organization?

ERIC Educational Resources Information Center

Nielsen, Marianne O.; Brown, Samantha

2012-01-01

The data from a longitudinal study of seven indigenous justice service organizations in four colonized countries were analyzed to identify the characteristics that made them "indigenous." Although nine common organizational characteristics emerged, of these, four are essential and specific to indigenous organizations (dependency on…

Child Maltreatment in the "Children of the Nineties": A Cohort Study of Risk Factors

ERIC Educational Resources Information Center

Sidebotham, Peter; Heron, Jon

2006-01-01

Aim: To analyze the multiple factors affecting the risk of maltreatment in young children within a comprehensive theoretical framework. Methods: The research is based on a large UK cohort study, the Avon Longitudinal Study of Parents and Children. Out of 14,256 children participating in the study, 293 were investigated by social services for…

Simple descriptive missing data indicators in longitudinal studies with attrition, intermittent missing data and a high number of follow-ups.

PubMed

Wærsted, Morten; Børnick, Taran Svenssen; Twisk, Jos W R; Veiersted, Kaj Bo

2018-02-13

Missing data in longitudinal studies may constitute a source of bias. We suggest three simple missing data indicators for the initial phase of getting an overview of the missingness pattern in a dataset with a high number of follow-ups. Possible use of the indicators is exemplified in two datasets allowing wave nonresponse; a Norwegian dataset of 420 subjects examined at 21 occasions during 6.5 years and a Dutch dataset of 350 subjects with ten repeated measurements over a period of 35 years. The indicators Last response (the timing of last response), Retention (the number of responded follow-ups), and Dispersion (the evenness of the distribution of responses) are introduced. The proposed indicators reveal different aspects of the missing data pattern, and may give the researcher a better insight into the pattern of missingness in a study with several follow-ups, as a starting point for analyzing possible bias. Although the indicators are positively correlated to each other, potential predictors of missingness can have a different relationship with different indicators leading to a better understanding of the missing data mechanism in longitudinal studies. These indictors may be useful descriptive tools when starting to look into a longitudinal dataset with many follow-ups.

High angle-of-attack aerodynamics of a strake-canard-wing V/STOL fighter configuration

NASA Technical Reports Server (NTRS)

Durston, D. A.; Schreiner, J. A.

1983-01-01

High angle-of-attack aerodynamic data are analyzed for a strake-canard-wing V/STOL fighter configuration. The configuration represents a twin-engine supersonic V/STOL fighter aircraft which uses four longitudinal thrust-augmenting ejectors to provide vertical lift. The data were obtained in tests of a 9.39 percent scale model of the configuration in the NASA Ames 12-Foot Pressure Wind Tunnel, at a Mach number of 0.2. Trimmed aerodynamic characteristics, longitudinal control power, longitudinal and lateral/directional stability, and effects of alternate strake and canard configurations are analyzed. The configuration could not be trimmed (power-off) above 12 deg angle of attack because of the limited pitch control power and the high degree of longitudinal instability (28 percent) at this Mach number. Aerodynamic center location was found to be controllable by varying strake size and canard location without significantly affecting lift and drag. These configuration variations had relatively little effect on the lateral/directional stability up to 10 deg angle of attack.

What Happens to a Nursing Home Chain When Private Equity Takes Over? A Longitudinal Case Study

PubMed Central

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

You can go home again: evidence from longitudinal data.

PubMed

Reagan, P B; Olsen, R J

2000-08-01

In this paper we analyze the economic and demographic factors that influence return migration, focusing on generation 1.5 immigrants. Using longitudinal data from the 1979 youth cohort of the National Longitudinal Surveys (NLSY79), we track residential histories of young immigrants to the United States and analyze the covariates associated with return migration to their home country. Overall, return migration appears to respond to economic incentives, as well as to cultural and linguistic ties to the United States and the home country. We find no role for welfare magnets in the decision to return, but we learn that welfare participation leads to lower probability of return migration. Finally, we see no evidence of a skill bias in return migration, where skill is measured by performance on the Armed Forces Qualifying Test.

A Longitudinal Study of Academic Progress Rate as a Result of Team and Institutional Variables at NCAA Division I Schools

ERIC Educational Resources Information Center

Hale, Jimmie Edwin

2014-01-01

This study explained Academic Progress Rate (APR) levels and differences in APR (DAPR) with team and institutional variables. Team variables included team gender, sport profile, and squad size. Institutional variables included individual variables aggregated to the institutional level. The data analyzed in this study was derived from the National…

Measuring Narcissism within Add Health: The Development and Validation of a New Scale

ERIC Educational Resources Information Center

Davis, Mark S.; Brunell, Amy B.

2012-01-01

This study reports the development of a measure of narcissism within the National Longitudinal Study of Adolescent Health (Add Health) data set. In Study 1, items were selected from Wave III to form the Add Health Narcissism Scale (AHNS). These were factor analyzed, yielding a single factor comprised of five subscales. We correlated the AHNS and…

An overview of longitudinal data analysis methods for neurological research.

PubMed

Locascio, Joseph J; Atri, Alireza

2011-01-01

The purpose of this article is to provide a concise, broad and readily accessible overview of longitudinal data analysis methods, aimed to be a practical guide for clinical investigators in neurology. In general, we advise that older, traditional methods, including (1) simple regression of the dependent variable on a time measure, (2) analyzing a single summary subject level number that indexes changes for each subject and (3) a general linear model approach with a fixed-subject effect, should be reserved for quick, simple or preliminary analyses. We advocate the general use of mixed-random and fixed-effect regression models for analyses of most longitudinal clinical studies. Under restrictive situations or to provide validation, we recommend: (1) repeated-measure analysis of covariance (ANCOVA), (2) ANCOVA for two time points, (3) generalized estimating equations and (4) latent growth curve/structural equation models.

Stability and change in the clinical course of schizoaffective disorder.

PubMed

Durla, Anca; Lenciu, M; Bredicean, C; Papava, I; Cristanovici, M

2013-01-01

Schizoaffective disorder currently raises several questions, one of them being related to the stability of the clinical diagnosis over time. The aim of this study is to identify the clinical and evolutional particularities in the longitudinal course of schizoaffective disorder. 44 subjects with a current diagnosis of schizoaffective disorder have been assessed prospectively. Following parameters were analyzed: socio-demographic (age at onset, gender, educational, professional and marital status at onset) and clinical (total duration of evolution, diagnosis at onset, duration of the evolution until the switch to the schizoaffective disorder diagnosis). Socio-demographic parameters are similar to those in literature and the clinical assessment revealed that schizoaffective disorder is present as a diagnosis along with the longitudinal course of other types of psychosis. Schizoaffective disorder appears as a heterogeneous pathology in terms of the longitudinal course.

Performance and Stability Characteristics of a Uni-Element Swirl Injector for Oxygen-Rich Stage Combustion Cycles

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.

Income Inequality and IQ.

ERIC Educational Resources Information Center

Murray, Charles

The importance of intelligence quotient (IQ) to income is analyzed using data from the National Longitudinal Survey of Youth, a study that began in 1979 with 12,686 subjects. Data for this study go through the 1994 interview wave, so that the most recent income data is for 1993. Statistical techniques are used to separate the influence of IQ from…

Longitudinal Study of Middle Grades Chemistry Professional Development: Enhancement of Personal Science Teaching Self-Efficacy and Outcome Expectancy

ERIC Educational Resources Information Center

Khourey-Bowers, Claudia; Simonis, Doris G.

2004-01-01

The purpose of this research was to enhance self-efficacy beliefs, chemistry content, and pedagogical content knowledge of middle grades teachers by incorporating specific design elements into professional development. This study analyzed the influence of program design on achieving gains in personal science teaching self-efficacy, outcome…

"I Didn't Realize How Hard It Would Be!": Tensions and Transformations in Becoming a Teacher

ERIC Educational Resources Information Center

Sydnor, Jackie

2017-01-01

This study explores the experience of becoming an elementary teacher in an educational climate where standardization and accountability increasingly affect what happens in classrooms across the country by following two beginning teachers. Specifically, this longitudinal study in which two first-year teachers' stories are analyzed and restoried…

The Long-Term Impact of Admission Policies: A Comparative Study of Two Emergent Research Institutions in Texas

ERIC Educational Resources Information Center

Crisp, Gloria; Horn, Catherine; Dizinno, Gerry; Barlow, Libby

2013-01-01

The present study explored the long-term impact of admission policies at two aspiring research institutions in Texas. Six years of longitudinal institutional data were analyzed for all full-time first time in college undergraduate students at both universities. Descriptive and inferential statistics were used to identify relationships and…

Building a Multicontextual Model of Latino College Enrollment: Student, School, and State-Level Effects

ERIC Educational Resources Information Center

Nunez, Anne-Marie; Kim, Dongbin

2012-01-01

Latinos' college enrollment rates, particularly in four-year institutions, have not kept pace with their population growth in the United States. Using three-level hierarchical generalized linear modeling, this study analyzes data from the Educational Longitudinal Study (ELS) to examine the influence of high school and state contexts, in addition…

Family Structure Effects on Maternal and Paternal Parenting in Low-Income Families

ERIC Educational Resources Information Center

Gibson-Davis, Christina M.

2008-01-01

Using longitudinal data from the Fragile Families and Child Wellbeing Survey, a birth cohort study, this study analyzes the effect of family structure on parenting for 3,402 mothers and 2,615 fathers. To address the problem of omitted variable bias, fixed effects methods are used to control for the presence of time-invariant unobserved…

Analyzing the School Evaluation Use Process To Make Evaluation Worth the Effort.

ERIC Educational Resources Information Center

Pechman, Ellen M.; King, Jean A.

This paper describes a structure for assessing the school evaluation use process developed from a longitudinal case study of districtwide and school level evaluation procedures in a large urban school district. Two fundamental questions guided the study: (1) Why isn't the evaluation process more useful to decision-makers and practitioners? and (2)…

Tracing the Building of Robert's Connections in Mathematical Problem Solving: A Sixteen-Year Study

ERIC Educational Resources Information Center

Ahluwalia, Anoop

2011-01-01

This research analyzes how external representations created by a student, Robert, helped him in building mathematical understanding over a sixteen-year period. Robert (also known as Bobby), was an original participant of the Rutgers longitudinal study where students were encouraged to work on problem-solving tasks with minimum intervention (Maher,…

Youth Employment in the Hospitality Sector.

ERIC Educational Resources Information Center

Schiller, Bradley R.

A study used data from the National Longitudinal Surveys of Youth to analyze the long-term effects of hospitality industry employment on youth. The subsample extracted for the study included all youth who were aged 16-24 in 1980 and employed in the civilian sector for pay at any time in the year. Statistics indicated the hospitality sector was…

What Happens to Students' English after One Year of English­-Medium Course Study at University?

ERIC Educational Resources Information Center

Gan, Zhengdong; Stapleton, Paul; Yang, Chi Cheung Ruby

2015-01-01

A much under-researched issue in higher education is the extent to which English-medium university courses help students improve their English proficiency in an ESL context. Adopting a longitudinal, mixed methods design in which quantitative and qualitative data were collected and analyzed, the current study tracked English language improvement,…

Parent-Child Conversations about Literacy: A Longitudinal, Observational Study

ERIC Educational Resources Information Center

Treiman, Rebecca; Decker, Kristina; Robins, Sarah; Ghosh, Dina; Rosales, Nicole

2018-01-01

Conversations about literacy-related matters with parents can help prepare children for formal literacy instruction. We studied these conversations using data gathered from fifty-six US families as they engaged in daily activities at home. Analyzing conversations when children were aged 1;10, 2;6, 3;6, and 4;2, we found that explicit talk about…

Socioeconomic Status and Asian American and Pacific Islander Students' Transition to College: A Structural Equation Modeling Analysis

ERIC Educational Resources Information Center

Museus, Samuel D.; Vue, Rican

2013-01-01

The purpose of this study is to examine socioeconomic differences in the interpersonal factors that influence college access among Asian Americans and Pacific Islanders (AAPIs). Data on 1,460 AAPIs from the Education Longitudinal Study (ELS: 02/06) were analyzed using structural equation modeling techniques. Findings suggest that parental…

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.…

Postsecondary Pathways and Persistence for STEM versus Non-STEM Majors: Among College Students with an Autism Spectrum Disorder

ERIC Educational Resources Information Center

Wei, Xin; Christiano, Elizabeth R. A.; Yu, Jennifer W.; Blackorby, Jose; Shattuck, Paul; Newman, Lynn A.

2014-01-01

Little is known about postsecondary pathways and persistence among college students with an autism spectrum disorder (ASD). This study analyzed data from the National Longitudinal Transition Study-2, 2001-2009, a nationally representative sample of students in special education with an ASD who progressed from high school to postsecondary…

Predictors of Risky Behavior and Offending for Adolescents with Mild Intellectual Disability

ERIC Educational Resources Information Center

Savage, Melissa N.; Bouck, Emily C.

2017-01-01

Adolescents with intellectual disability (ID) engage in risky behavior and offending. However, little is known on the impact school-related predictors have on engagement in risky behaviors for adolescents with ID. This study analyzed secondary data from the National Longitudinal Transition Study-2 (NLTS2) to determine levels of engagement in risky…

Postsecondary Pathways and Persistence for STEM versus Non-STEM Majors; Among College Students with an Autism Spectrum Disorder

ERIC Educational Resources Information Center

Wei, Xin; Christiano, Elizabeth R.; Yu, Jennifer W.; Blackorby, Jose; Shattuck, Paul; Newman, Lynn

2014-01-01

Little is known about postsecondary pathways and persistence among college students with an Autism Spectrum Disorder (ASD). This study analyzed data from the National Longitudinal Transition Study-2, 2001-2009, a nationally representative sample of students in special education with an ASD who progressed from high school to postsecondary…

Gender-Role Attitudes and Behavior across the Transition to Parenthood

ERIC Educational Resources Information Center

Katz-Wise, Sabra L.; Priess, Heather A.; Hyde, Janet S.

2010-01-01

On the basis of social structural theory and identity theory, the current study examined changes in gender-role attitudes and behavior across the first-time transition to parenthood and following the birth of a second child for experienced mothers and fathers. Data were analyzed from the ongoing longitudinal Wisconsin Study of Families and Work.…

Social support and health-related quality of life in women with breast cancer: a longitudinal study.

PubMed

Leung, Janni; Pachana, Nancy A; McLaughlin, Deirdre

2014-09-01

A breast cancer diagnosis is a distressing event that impacts on physical and psychological functioning. This study examined the longitudinal relationships among a diagnosis of breast cancer, social support, and health-related quality of life (HRQOL). Participants were 412 women from the 1946-1951 birth cohort of the Australian Longitudinal Study on Women's Health who self-reported a new diagnosis of breast cancer between 1998 and 2007. The three surveys of longitudinal data analyzed included data 3 years before diagnosis, at diagnosis (baseline), and 3 years after diagnosis (follow-up). Social support was measured using the 19-item Medical Outcomes Study Social Support Survey; HRQOL was measured using the Medical Outcomes Study 36-item Short-Form Health Survey. Compared with pre-diagnosis HRQOL, women newly diagnosed with breast cancer reported significantly poorer HRQOL in subscales related to pain, physical functioning, and health and vitality. At 3-year follow-up, HRQOL had improved in most domains to levels consistent with pre-diagnosis. Levels of social support remained stable across time. The structural equation model showed that social support was positively predictive of better physical and mental HRQOL at 3-year follow-up. Longitudinal analyses indicate that social support appears to be an important predictor of HRQOL in women diagnosed with breast cancer. In particular, positive emotional and informational support that may normally be provided by a partner is important in maintaining HRQOL. Identification of those lacking social support, especially patients without partners, will enable them to be guided to appropriate support networks and programs. Copyright © 2014 John Wiley & Sons, Ltd.

Serum Uric Acid Levels and Risk of Incident Hypertriglyceridemia: A Longitudinal Population-based Epidemiological Study.

PubMed

Zheng, Rongjiong; Ren, Ping; Chen, Qingmei; Yang, Tianmeng; Chen, Changxi; Mao, Yushan

2017-09-01

Hypertriglyceridemia is one of lipid metabolism abnormalities; however, it is still debatable whether serum uric acid is a cause or a consequence of hypertriglyceridemia. We performed the study to investigate the longitudinal association between serum uric acid levels and hypertriglyceridemia. The study included 4190 subjects without hypertriglyceridemia. The subjects had annual health examinations for 8 years to assess incident hyperglyceridemia, and the subjects were divided into groups based on the serum uric acid quartile. Cox regression models were used to analyze the risk factors of development hypertriglyceridemia. During follow-up, 1461 (34.9%) subjects developed hypertriglyceridemia over 8 years of follow-up. The cumulative incidence of hypertriglyceridemia was 28.2%, 29.1%, 36.9%, and 45.6% in quartile 1,2,3 and 4, respectively ( P for trend <0.001). Cox regression analyses indicated that serum uric acid levels were independently and positively associated with the risk of incident hypertriglyceridemia. Hypertriglyceridemia has become a serious public health problem. This longitudinal study demonstrates that high serum uric acid levels increase the risk of hypertriglyceridemia. © 2017 by the Association of Clinical Scientists, Inc.

Longitudinal waves in carbon nanotubes in the presence of transverse magnetic field and elastic medium

NASA Astrophysics Data System (ADS)

Liu, Hu; Liu, Hua; Yang, Jialing

2017-09-01

In the present paper, the coupling effect of transverse magnetic field and elastic medium on the longitudinal wave propagation along a carbon nanotube (CNT) is studied. Based on the nonlocal elasticity theory and Hamilton's principle, a unified nonlocal rod theory which takes into account the effects of small size scale, lateral inertia and radial deformation is proposed. The existing rod theories including the classic rod theory, the Rayleigh-Love theory and Rayleigh-Bishop theory for macro solids can be treated as the special cases of the present model. A two-parameter foundation model (Pasternak-type model) is used to represent the elastic medium. The influence of transverse magnetic field, Pasternak-type elastic medium and small size scale on the longitudinal wave propagation behavior of the CNT is investigated in detail. It is shown that the influences of lateral inertia and radial deformation cannot be neglected in analyzing the longitudinal wave propagation characteristics of the CNT. The results also show that the elastic medium and the transverse magnetic field will also affect the longitudinal wave dispersion behavior of the CNT significantly. The results obtained in this paper are helpful for understanding the mechanical behaviors of nanostructures embedded in an elastic medium.

Longitudinal Beam Diagnostics for the ILC Injectors and Bunch Compressors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Piot, Philippe; Bracke, Adam; Demir, Veysel

2010-12-01

We present a diagnostics suite and analyze techniques for setting up the longitudinal beam dynamics in ILC e⁻ injectors and e⁺ and e⁻ bunch compressors. Techniques to measure the first order moments and recover the first order longitudinal transfer map of the injector's intricate bunching scheme are presented. Coherent transition radiation diagnostics needed to measure and monitor the bunch length downstream of the ~5 GeV bunch compressor are investigated using a vector diffraction model.

Risky online behaviors among adolescents: Longitudinal relations among problematic Internet use, cyberbullying perpetration, and meeting strangers online

PubMed Central

Gámez-Guadix, Manuel; Borrajo, Erika; Almendros, Carmen

2016-01-01

Background and aims This study aims to analyze the cross-sectional and longitudinal relationship between three major risky online behaviors during adolescence: problematic Internet use, cyberbullying perpetration, and meeting strangers online. An additional objective was to study the role of impulsivity–irresponsibility as a possible explanatory variable of the relationships between these risky online behaviors. Methods The study sample was 888 adolescents that completed self-report measures at time 1 and time 2 with an interval of 6 months. Results The findings showed a significant cross-sectional relationship between the risky online behaviors analyzed. At the longitudinal level, problematic Internet use at time 1 predicted an increase in the perpetration of cyberbullying and meeting strangers online at time 2. Furthermore, meeting strangers online increased the likelihood of cyberbullying perpetration at time 2. Finally, when impulsivity–irresponsibility was included in the model as an explanatory variable, the relationships previously found remained significant. Discussion These results extend traditional problem behavior theory during adolescence, also supporting a relationship between different risky behaviors in cyberspace. In addition, findings highlighted the role of problematic Internet use, which increased the chances of developing cyberbullying perpetration and meeting strangers online over time. However, the results suggest a limited role of impulsivity–irresponsibility as an explicative mechanism. Conclusions The findings suggest that various online risk activities ought to be addressed together when planning assessment, prevention and intervention efforts. PMID:28092196

Longitudinal associations of burnout with heart rate variability in patients following acute coronary syndrome: A one-year follow-up study.

PubMed

Zhang, Min; Liu, Ling; Shi, Yunke; Yang, Yanfei; Yu, Xiaoju; Angerer, Peter; Kristensen, Tage S; Li, Jian

2018-05-25

To investigate longitudinal associations of burnout with heart rate variability (HRV) in patients after their first acute coronary syndrome (ACS). Two hundred eight patients participated in this one-year follow-up study. On the day before discharge, their personal burnout level was assessed by the Copenhagen Burnout Inventory. HRV signals were collected at four time points: the day before discharge, one month, six month and one year after discharge. HRV was measured by 24-h ambulatory electrocardiography and analyzed in time and frequency domains. Generalized estimating equations were applied to analyze the associations of burnout at baseline with longitudinal tracking of HRV during follow-up. After adjusting for relevant confounding factors, high burnout at baseline was significantly associated with low SDNN, a time domain measure of HRV [regression coefficient = -0.087, 95% CI = (-0.136, -0.038) by an increase per SD in burnout score, p = 0.001]. Also, baseline burnout was inversely associated with five frequency domain measures, i.e., HF [coefficient = -0.179, 95% CI = (-0.352, -0.006), p = 0.043], LF [coefficient = -0.171, 95% CI = (-0.319, -0.023), p = 0.024], VLF [coefficient = -0.367, 95% CI = (-0.483, -0.250), p < 0.001], ULF [coefficient = -0.268, 95% CI = (-0.351, -0.184), p < 0.001], and TP [coefficient = -0.283, 95% CI = (-0.340, -0.165), p < 0.001]. Personal burnout is longitudinally associated with decreased HRV during one-year period among patients after first ACS. Copyright © 2018 Elsevier Inc. All rights reserved.

Longitudinal measurements of oxygen consumption in growing infants during the first weeks after birth: old data revisited.

PubMed

Sinclair, J C; Thorlund, K; Walter, S D

2013-01-01

In a study conducted in 1966-1969, longitudinal measurements were made of the metabolic rate in growing infants. Statistical methods for analyzing longitudinal data weren't readily accessible at that time. To measure minimal rates of oxygen consumption (V·O2, ml/min) in growing infants during the first postnatal weeks and to determine the relationships between postnatal increases in V·O2, body size and postnatal age. We studied 61 infants of any birth weight or gestational age, including 19 of very low birth weight. The infants, nursed in incubators, were clinically well and without need of oxygen supplementation or respiratory assistance. Serial measures of V·O2 using a closed-circuit method were obtained at approximately weekly intervals. V·O2 was measured under thermoneutral conditions with the infant asleep or resting quietly. Data were analyzed using mixed-effects models. During early postnatal growth, V·O2 rises as surface area (m(2))(1.94) (standard error, SE 0.054) or body weight (kg)(1.24) (SE 0.033). Multivariate analyses show statistically significant effects of both size and age. Reference intervals (RIs) for V·O2 for fixed values of body weight and postnatal age are presented. As V·O2 rises with increasing size and age, there is an increase in the skin-operative environmental temperature gradient (T skin-op) required for heat loss. Required T skin-op can be predicted from surface area and heat loss (heat production minus heat storage). Generation of RIs for minimal rates of V·O2 in growing infants from the 1960s was enabled by application of mixed-effects statistical models for analyses of longitudinal data. Results apply to the precaffeine era of neonatal care. Copyright © 2013 S. Karger AG, Basel.

Longitudinal Associations across Prematurity, Attention, and Language in School-Age Children

ERIC Educational Resources Information Center

Mahurin-Smith, Jamie; DeThorne, Laura S.; Petrill, Stephen A.

2017-01-01

Purpose: This research note explores the potential role of attention in mediating previously reported associations between language outcomes and prematurity. Method: As a follow-up investigation to Mahurin Smith, DeThorne, Logan, Channell, and Petrill (2014), we employed multilevel modeling to analyze longitudinal data on language and attention…

Analyzing Longitudinal Item Response Data via the Pairwise Fitting Method

ERIC Educational Resources Information Center

Fu, Zhi-Hui; Tao, Jian; Shi, Ning-Zhong; Zhang, Ming; Lin, Nan

2011-01-01

Multidimensional item response theory (MIRT) models can be applied to longitudinal educational surveys where a group of individuals are administered different tests over time with some common items. However, computational problems typically arise as the dimension of the latent variables increases. This is especially true when the latent variable…

PARAMETER EVALUATION AND MODEL VALIDATION OF OZONE EXPOSURE ASSESSMENT USING HARVARD SOUTHERN CALIFORNIA CHRONIC OZONE EXPOSURE STUDY DATA

EPA Science Inventory

To examine factors influencing long-term ozone exposures by children living in urban communities, we analyzed longitudinal data on personal, indoor, and outdoor ozone concentrations as well as related housing and other questionnaire information collected in the one-year-long Harv...

CETA: Is It Equitable for Women? A Rand Note.

ERIC Educational Resources Information Center

Berryman, Sue E.; And Others

A study assessed whether the Comprehensive Employment and Training Act (CETA) equitably allocates its training, employment, occupational, and wage benefits by sex. To analyze the sex equity of CETA's resource distribution, researchers used data from the Continuous Longitudinal Manpower Survey (CLMS) for fiscal 1976, 1977, and 1978 CETA enrollees.…

Effect of Transition Planning on Postsecondary Support Receipt by Students with Disabilities

ERIC Educational Resources Information Center

Newman, Lynn A; Madaus, Joseph W.; Javitz, Harold S.

2016-01-01

Data from the National Longitudinal Transition Study-2 were analyzed to determine the effect of receiving transition planning education and having a transition plan that specified needed postsecondary accommodations on the receipt of disability-specific services and generally available supports at the postsecondary level by students with…

Can We Predict Disruptive School Behavior?

ERIC Educational Resources Information Center

Eamon, Mary Keegan; Altshuler, Sandra J.

2004-01-01

This study examined whether child, parental, and socioenvironmental factors predict disruptive school behavior two years later. Data from a sample of 10-to 12-year-old youths, including 289 African American, 183 Hispanic/Latino, and 335 non-Hispanic white youths from the National Longitudinal Survey of Youth were analyzed. Findings indicate that…

Social Networks, Communication Styles, and Learning Performance in a CSCL Community

ERIC Educational Resources Information Center

Cho, Hichang; Gay, Geri; Davidson, Barry; Ingraffea, Anthony

2007-01-01

The aim of this study is to empirically investigate the relationships between communication styles, social networks, and learning performance in a computer-supported collaborative learning (CSCL) community. Using social network analysis (SNA) and longitudinal survey data, we analyzed how 31 distributed learners developed collaborative learning…

What Good Predictors of Marijuana Use Are Good For: A Synthesis of Research.

ERIC Educational Resources Information Center

Derzon, James H.; Lipsey, Mark W.

1999-01-01

Analyzes correlates of marijuana use based on 3,690 effect sizes coded from 86 prospective longitudinal studies. Summarizes findings on strength of relationships for categorizing predictor variables, and implications of these relationships. Findings are relevant for intervention programmers and policymakers since they identify characteristics of…

Neighborhoods and Schools as Competing and Reinforcing Contexts for Educational Attainment

ERIC Educational Resources Information Center

Owens, Ann

2010-01-01

Scholars hypothesize that both neighborhood and school contexts influence educational attainment, but few have considered both contexts simultaneously. Using data from the National Longitudinal Study of Adolescent Health, the author analyzes how school and neighborhood contexts are jointly related to high school and college graduation. She finds…

Effects of Technology Immersion on Middle School Students' Learning Opportunities and Achievement

ERIC Educational Resources Information Center

Shapley, Kelly; Sheehan, Daniel; Maloney, Catherine; Caranikas-Walker, Fanny

2011-01-01

An experimental study of the Technology Immersion model involved comparisons between 21 middle schools that received laptops for each teacher and student, instructional and learning resources, professional development, and technical and pedagogical support, and 21 control schools. Using hierarchical linear modeling to analyze longitudinal survey…

Mathematics from High School to Community College: Preparation, Articulation, and College Un-Readiness

ERIC Educational Resources Information Center

Jaffe, Louise

2012-01-01

This research studied the role of mathematics as a roadblock to college completion for community college-bound students in California. Using longitudinal quantitative analysis, I observed the educational pipeline between high school and community college and analyzed how different high school mathematics histories predicted readiness, or…

The Relationship of Socioeconomic Status and Sex to Body Size, Skeletal Maturation, and Cognitive Status of Guatemala City Schoolchildren.

ERIC Educational Resources Information Center

Bogin, Barry; MacVean, Robert B.

1983-01-01

Longitudinal data from a study of child development in Guatemala City were used to describe the influence of socioeconomic status and sex on physical and cognitive growth status. The correlation between growth status variables was also analyzed. (Author/RH)

Credit Building in IDA Programs: Early Findings of a Longitudinal Study

ERIC Educational Resources Information Center

Birkenmaier, Julie; Curley, Jami; Kelly, Patrick

2012-01-01

Objective: This article reports on the impact of the Individual Development Account (IDA) program on credit. Method: Using a convenience sample of IDA participants (N = 165), data were analyzed using paired sample "t" tests, independent sample "t" test, one-way analysis of variance, Mann-Whitney "U" Tests, and…

Creating Intercontextuality in Students Learning Trajectories. Opportunities and Difficulties

ERIC Educational Resources Information Center

Wiig, Camilla; Silseth, Kenneth; Erstad, Ola

2018-01-01

This article explores how opportunities and limitations in creating intercontextualtiy between everyday and scientific ideas emerge in teacher-student interactions, with a particular focus on the teacher's role. The article draws on data from an empirical, longitudinal, study in a lower secondary school in Norway to analyze student-teacher…

Math Intervention Teachers' Pedagogical Content Knowledge and Student Achievement

ERIC Educational Resources Information Center

Waller, Lisa Ivey

2012-01-01

This research investigated the relationship of math intervention teachers' (MITs) pedagogical content knowledge (PCK) and students' math achievement gains in primary math interventions. The Kentucky Center for Mathematics gathered data on the MITs and primary math intervention students included in this study. Longitudinal data were analyzed for a…

Against Conventional Wisdom: Factors Influencing Hispanic Students' Reading Achievement

ERIC Educational Resources Information Center

Percell, Jay C.; Kaufman, Kristina

2013-01-01

The researchers performed a variable analysis of the 2002 Educational Longitudinal Study data investigating factors that influence students' reading scores on standardized tests. Hispanic and non-Hispanic Scores were analyzed and controlling variables were compared to determine the effect of each on both populations. Certain variables commonly…

The Amsterdam Growth and Health Longitudinal Study. The past (1976-1996) and future (1997-?).

PubMed

Kemper, H C; van Mechelen, W; Post, G B; Snel, J; Twisk, J W; van Lenthe, F J; Welten, D C

1997-07-01

This article presents an overview of the Amsterdam Growth and Health Longitudinal Study (AGAHLS). This study was started in the 1970s, following a whole sample of 500 healthy 13-year-old boys and girls from two secondary schools. During the school period (12-17 years) annual measurements were performed with respect to anthropometrics, physiological and psychological parameters, lifestyle characteristics (activity, diet, smoking) and health parameters. A multiple longitudinal design was applied with overlapping birth cohorts and a cross-sectional measured control group to monitor for confounding factors such as time of measurement, cohort, dropout and testing effects. Emphasis is also placed on measures that enhance adherence of the subjects. The follow-up was extended with repeated measurements at age 21, 26 and 28. This enabled us to analyze the data with respect to tracking characteristics of biological and lifestyle variables over a period of 15 years between adolescence and adulthood and also to investigate quasi-causal relationships between the effects of a healthy lifestyle and indicators for cardiovascular diseases (CVD). Also new methods such as measurement of atherosclerosis and osteoporosis will be added and related to longitudinal measurements of the same subjects in the past. The main results that were obtained in the past are summarized and research questions for the near future are explained.

How do Rumination and Social Problem Solving Intensify Depression? A Longitudinal Study.

PubMed

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.

Longitudinal, reciprocal effects of social skills and achievement from kindergarten to eighth grade.

PubMed

Caemmerer, Jacqueline M; Keith, Timothy Z

2015-08-01

Previous research suggests that students' social skills and achievement are interrelated, and some findings support bi-directional effects between the two constructs. The purpose of this research study was to estimate the possible longitudinal and reciprocal effects of social skills and achievement for kindergarten through eighth grade students. Data from the Early Childhood Longitudinal Study program were analyzed; teachers' ratings of students' social skills and students' standardized math and reading achievement performance were collected 4 and 5 times, respectively. Latent variable structural equation modeling was used to test a panel model of reciprocal, longitudinal effects of social skills and achievement. The results suggest that the effects of students' social skills and achievement are bi-directional, but the effects of students' achievement on their later social skills are stronger than the effects of social skills on achievement. The significant effects of students' social skills on their later achievement are mostly indirect. These findings suggest that the future social skills of students who struggle academically may be of particular concern to educators, and intervention and prevention efforts aimed to address both social and achievement skills may help remediate the other skill in the future. Copyright © 2015 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.

Is Social Capital a Determinant of Oral Health among Older Adults? Findings from the English Longitudinal Study of Ageing

PubMed Central

Rouxel, Patrick; Tsakos, Georgios; Demakakos, Panayotes; Zaninotto, Paola; Chandola, Tarani; Watt, Richard Geddie

2015-01-01

There are a number of studies linking social capital to oral health among older adults, although the evidence base mainly relies on cross-sectional study designs. The possibility of reverse causality is seldom discussed, even though oral health problems could potentially lead to lower social participation. Furthermore, few studies clearly distinguish between the effects of different dimensions of social capital on oral health. The objective of the study was to examine the longitudinal associations between individual social capital and oral health among older adults. We analyzed longitudinal data from the 3rd and 5th waves of the English Longitudinal Study of Ageing (ELSA). Structural social capital was operationalized using measures of social participation, and volunteering. Number of close ties and perceived emotional support comprised the functional dimension of social capital. Oral health measures were having no natural teeth (edentate vs. dentate), self-rated oral health and oral health-related quality of life. Time-lag and autoregressive models were used to explore the longitudinal associations between social capital and oral health. We imputed all missing data, using multivariate imputation by chained equations. We found evidence of bi-directional longitudinal associations between self-rated oral health, volunteering and functional social capital. Functional social capital was a strong predictor of change in oral health-related quality of life – the adjusted odds ratio of reporting poor oral health-related quality of life was 1.75 (1.33–2.30) for older adults with low vs. high social support. However in the reverse direction, poor oral health-related quality of life was not associated with changes in social capital. This suggests that oral health may not be a determinant of social capital. In conclusion, social capital may be a determinant of subjective oral health among older adults rather than edentulousness, despite many cross-sectional studies on the latter. PMID:25992569

The educational, racial and gender crossovers in life satisfaction: Findings from the longitudinal Health and Retirement Study.

PubMed

Zhang, Wei; Braun, Kathryn L; Wu, Yan Yan

2017-11-01

To examine variations in life satisfaction by education, gender, and race/ethnicity over a period of eight years among middle-aged and older Americans. Mixed-effects models were used to analyze five waves (2006, 2008, 2010, 2012 and 2014) of longitudinal data from 16,163 participants born 1890-1953 in the U.S. Health and Retirement Study. Life satisfaction was higher in older adults, and the Great Recession had great impact on life satisfaction. Crossover interactions were found by gender, education, and race/ethnicity. Higher education was associated with higher life satisfaction for both genders, with stronger effects for females. Hispanics had the higher level of life satisfaction than non-Hispanic Whites and African Americans. Longitudinal evidence revealed disparities in life satisfaction. The racial/ethnic differences in the impact of education suggest that the economic and health returns of education vary by social group. Researchers should continue to examine reasons for these disparities. Copyright © 2017 Elsevier B.V. All rights reserved.

Association between Cardiovascular Health Score and Carotid Intima-Media Thickness: Cross-Sectional Analysis of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) Baseline Assessment.

PubMed

Santos, Itamar S; Goulart, Alessandra C; Pereira, Alexandre C; Lotufo, Paulo A; Benseñor, Isabela M

2016-12-01

The American Heart Association aims to reduce the burden of cardiovascular disease in this decade by improving seven ideal cardiovascular health (CVH) characteristics in the population. The aim of this study was to quantify the association between the American Heart Association's CVH score and values for carotid intima-media thickness (CIMT) in the Brazilian Longitudinal Study of Adult Health baseline assessment. The Brazilian Longitudinal Study of Adult Health is a multicenter cohort study of civil servants aged 35 to 74 years in Brazil. In this study, the investigators analyzed 9,662 individuals with no previous cardiovascular disease. The distribution of CIMT values (categorized into age-, sex-, and race-specific quartiles) was analyzed according to CVH scores using χ 2 trend tests. Linear and multinomial regression models were built to evaluate the association between CIMT and CVH score. A significant increase was observed in the proportion of individuals within the first and second CIMT quartiles, as well as a decrease within the fourth quartile with higher CVH score strata (P for trend < .001). A 1-point increase in CVH score was associated in adjusted models with a decrease of 0.011 mm in CIMT and an odds ratio of 0.79 (95% CI, 0.77-0.81) of having CIMT in the fourth quartile. However, nearly 16% of individuals with optimal CVH scores had CIMT values in the highest quartile. In this study, significant associations were found between CIMT and CVH score in a large sample of middle-aged adults. However, a high CVH score did not warrant the absence of a significant subclinical atherosclerotic burden. Copyright © 2016 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.

Automated boundary segmentation and wound analysis for longitudinal corneal OCT images

NASA Astrophysics Data System (ADS)

Wang, Fei; Shi, Fei; Zhu, Weifang; Pan, Lingjiao; Chen, Haoyu; Huang, Haifan; Zheng, Kangkeng; Chen, Xinjian

2017-03-01

Optical coherence tomography (OCT) has been widely applied in the examination and diagnosis of corneal diseases, but the information directly achieved from the OCT images by manual inspection is limited. We propose an automatic processing method to assist ophthalmologists in locating the boundaries in corneal OCT images and analyzing the recovery of corneal wounds after treatment from longitudinal OCT images. It includes the following steps: preprocessing, epithelium and endothelium boundary segmentation and correction, wound detection, corneal boundary fitting and wound analysis. The method was tested on a data set with longitudinal corneal OCT images from 20 subjects. Each subject has five images acquired after corneal operation over a period of time. The segmentation and classification accuracy of the proposed algorithm is high and can be used for analyzing wound recovery after corneal surgery.

Magnetic field of longitudinal gradient bend

NASA Astrophysics Data System (ADS)

Aiba, Masamitsu; Böge, Michael; Ehrlichman, Michael; Streun, Andreas

2018-06-01

The longitudinal gradient bend is an effective method for reducing the natural emittance in light sources. It is, however, not a common element. We have analyzed its magnetic field and derived a set of formulae. Based on the derivation, we discuss how to model the longitudinal gradient bend in accelerator codes that are used for designing electron storage rings. Strengths of multipole components can also be evaluated from the formulae, and we investigate the impact of higher order multipole components in a very low emittance lattice.

Does pre-school improve cognitive abilities among children with early-life stunting? A longitudinal study for Peru

PubMed Central

Cueto, Santiago; León, Juan; Miranda, Alejandra; Dearden, Kirk; Crookston, Benjamin T.; Behrman, Jere R.

2017-01-01

Several studies in developing countries have found that children who experience growth faltering in the first years of life show lower cognitive abilities than their peers. In this study, we use the Young Lives longitudinal dataset in Peru to analyze if attending pre-school affects cognitive abilities at age five years, and if there is an interaction with HAZ at age one year. Using instrumental variables we found, for receptive vocabulary, a positive effect of attending Jardines (formal) pre-schools; the effect of attending PRONOEI (community-based) pre-schools was not significant. More years attending Jardines was more beneficial for children who were better nourished. We suggest working to improve the quality of PRONOEIs, and with teachers on targeting children of lower nutritional status. PMID:28428683

Transverse versus Longitudinal Incisions for Femoral Artery Exposure in Treating Patients with Peripheral Vascular Disease.

PubMed

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.

A Propensity Score Matching Study of Participation in Community Activities: A Path to Positive Outcomes for Youth in New Zealand?

ERIC Educational Resources Information Center

O'Connor, Seini; Jose, Paul E.

2012-01-01

Extracurricular activities are important in many young people's lives and have been associated with positive academic, psychological, and social outcomes. However, most previous research has been limited to school-based activities in the North American context. This study expands existing literature by analyzing longitudinal data from more than…

Predictors of Suicidal Ideation in Late Childhood and Adolescence: A 5-Year Follow-Up of Two Nationally Representative Cohorts in the Republic of Korea

ERIC Educational Resources Information Center

Park, Sunhee

2013-01-01

This study explores the trajectory of suicidal ideation in childhood and adolescence and identifies its strong predictors. Secondary data obtained from two nationally representative cohorts of South Korean youth were longitudinally analyzed using frequencies, percentages, and discrete time survival analysis. This study revealed an increase in the…

Middle Childhood Success and Economic Mobility. The Social Genome Project

ERIC Educational Resources Information Center

Aber, J. Lawrence; Grannis, Kerry Searle; Owen, Stephanie; Sawhill, Isabel V.

2013-01-01

This study uses data from the Early Childhood Longitudinal Study, Kindergarten Class of 1998-1999 (ECLS-K) to analyze competencies that children need to master by the end of elementary school, the extent to which they are doing so, what might be done to improve their performance, and how this might affect their ultimate ability to earn a living…

Does Independent Research with a Faculty Member Enhance Four-Year Graduation and Graduate/Professional Degree Plans? Convergent Results with Different Analytical Methods

ERIC Educational Resources Information Center

Kilgo, Cindy A.; Pascarella, Ernest T.

2016-01-01

This study examines the effects of undergraduate students participating in independent research with faculty members on four-year graduation and graduate/professional degree aspirations. We analyzed four-year longitudinal data from the Wabash National Study of Liberal Arts Education using multiple analytic techniques. The findings support the…

Novice Teachers' Use of Student Thinking and Learning as Evidence of Teaching Effectiveness: A Longitudinal Study of Video-Enhanced Teacher Preparation

ERIC Educational Resources Information Center

Santagata, Rossella; Taylor, Karen

2018-01-01

This study examines whether preservice teachers' experiences with video analyses during teacher preparation have long-lasting effects on their practices once they enter the profession. Specifically, the authors examined whether teachers who had opportunities to analyze student thinking and learning during teacher preparation continued to do so…

From Early Aspirations to Actual Attainment: The Effects of Economic Status and Educational Expectations on University Pursuit

ERIC Educational Resources Information Center

Wu, Ching-Ling; Bai, Haiyan

2015-01-01

This study investigated the effects of economic status and the educational expectations of significant others on early university aspirations and actual university attainment. The study analyzed two-wave longitudinal data collected from 1,595 Taiwanese students in their 9th grade in middle school and in their freshman year at universities. The…

Boys' and Girls' Weight Status and Math Performance from Kindergarten Entry through Fifth Grade: A Mediated Analysis

ERIC Educational Resources Information Center

Gable, Sara; Krull, Jennifer L.; Chang, Yiting

2012-01-01

This study tests a mediated model of boys' and girls' weight status and math performance with 6,250 children from the Early Childhood Longitudinal Study. Five data points spanning kindergarten entry (mean age = 68.46 months) through fifth grade (mean age = 134.60 months) were analyzed. Three weight status groups were identified: persistent…

Serious fighting-related injuries produce a significant reduction in intelligence.

PubMed

Schwartz, Joseph A; Beaver, Kevin M

2013-10-01

Fighting-related injuries are common among adolescents within the United States, but how such injuries relate to subsequent cognitive functioning remains unclear. In particular, the long-term effect of fighting-related injuries suffered during important developmental periods, such as adolescence, on subsequent cognitive functioning has been overlooked by previous studies. The purpose of this study is to examine the association between sustaining serious fighting-related injuries and changes in verbal intelligence (IQ) over a 5- to 6-year time period. Longitudinal multivariate statistical models were used to analyze data from the National Longitudinal Study of Adolescent Health collected between 1994 and 2002 and analyzed in 2013. Even a single fighting-related injury resulted in a significant reduction in IQ over time even after controlling for age, race, sex, and changes in socioeconomic status (SES) over the study period. Additionally, females experienced a significantly greater reduction in IQ from each fighting-related injury than males. Fighting-related injuries have a significant impact on subsequent cognitive functioning and intelligence. The implications for future policies and research are discussed in more detail. Copyright © 2013 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

A Repeated Trajectory Class Model for Intensive Longitudinal Categorical Outcome

PubMed Central

Lin, Haiqun; Han, Ling; Peduzzi, Peter N.; Murphy, Terrence E.; Gill, Thomas M.; Allore, Heather G.

2014-01-01

This paper presents a novel repeated latent class model for a longitudinal response that is frequently measured as in our prospective study of older adults with monthly data on activities of daily living (ADL) for more than ten years. The proposed method is especially useful when the longitudinal response is measured much more frequently than other relevant covariates. The repeated trajectory classes represent distinct temporal patterns of the longitudinal response wherein an individual’s membership in the trajectory classes may renew or change over time. Within a trajectory class, the longitudinal response is modeled by a class-specific generalized linear mixed model. Effectively, an individual may remain in a trajectory class or switch to another as the class membership predictors are updated periodically over time. The identification of a common set of trajectory classes allows changes among the temporal patterns to be distinguished from local fluctuations in the response. An informative event such as death is jointly modeled by class-specific probability of the event through shared random effects. We do not impose the conditional independence assumption given the classes. The method is illustrated by analyzing the change over time in ADL trajectory class among 754 older adults with 70500 person-months of follow-up in the Precipitating Events Project. We also investigate the impact of jointly modeling the class-specific probability of the event on the parameter estimates in a simulation study. The primary contribution of our paper is the periodic updating of trajectory classes for a longitudinal categorical response without assuming conditional independence. PMID:24519416

Designs and Methods in School Improvement Research: A Systematic Review

ERIC Educational Resources Information Center

Feldhoff, Tobias; Radisch, Falk; Bischof, Linda Marie

2016-01-01

Purpose: The purpose of this paper is to focus on challenges faced by longitudinal quantitative analyses of school improvement processes and offers a systematic literature review of current papers that use longitudinal analyses. In this context, the authors assessed designs and methods that are used to analyze the relation between school…

Bayesian Analysis of Longitudinal Data Using Growth Curve Models

ERIC Educational Resources Information Center

Zhang, Zhiyong; Hamagami, Fumiaki; Wang, Lijuan Lijuan; Nesselroade, John R.; Grimm, Kevin J.

2007-01-01

Bayesian methods for analyzing longitudinal data in social and behavioral research are recommended for their ability to incorporate prior information in estimating simple and complex models. We first summarize the basics of Bayesian methods before presenting an empirical example in which we fit a latent basis growth curve model to achievement data…

Making Full Use of the Longitudinal Design of the Current Population Survey: Methods for Linking Records Across 16 Months *

PubMed Central

Drew, Julia A. Rivera; Flood, Sarah; Warren, John Robert

2015-01-01

Data from the Current Population Survey (CPS) are rarely analyzed in a way that takes advantage of the CPS’s longitudinal design. This is mainly because of the technical difficulties associated with linking CPS files across months. In this paper, we describe the method we are using to create unique identifiers for all CPS person and household records from 1989 onward. These identifiers—available along with CPS basic and supplemental data as part of the on-line Integrated Public Use Microdata Series (IPUMS)—make it dramatically easier to use CPS data for longitudinal research across any number of substantive domains. To facilitate the use of these new longitudinal IPUMS-CPS data, we also outline seven different ways that researchers may choose to link CPS person records across months, and we describe the sample sizes and sample retention rates associated with these seven designs. Finally, we discuss a number of unique methodological challenges that researchers will confront when analyzing data from linked CPS files. PMID:26113770

Detecting and analyzing research communities in longitudinal scientific networks.

PubMed

Leone Sciabolazza, Valerio; Vacca, Raffaele; Kennelly Okraku, Therese; McCarty, Christopher

2017-01-01

A growing body of evidence shows that collaborative teams and communities tend to produce the highest-impact scientific work. This paper proposes a new method to (1) Identify collaborative communities in longitudinal scientific networks, and (2) Evaluate the impact of specific research institutes, services or policies on the interdisciplinary collaboration between these communities. First, we apply community-detection algorithms to cross-sectional scientific collaboration networks and analyze different types of co-membership in the resulting subgroups over time. This analysis summarizes large amounts of longitudinal network data to extract sets of research communities whose members have consistently collaborated or shared collaborators over time. Second, we construct networks of cross-community interactions and estimate Exponential Random Graph Models to predict the formation of interdisciplinary collaborations between different communities. The method is applied to longitudinal data on publication and grant collaborations at the University of Florida. Results show that similar institutional affiliation, spatial proximity, transitivity effects, and use of the same research services predict higher degree of interdisciplinary collaboration between research communities. Our application also illustrates how the identification of research communities in longitudinal data and the analysis of cross-community network formation can be used to measure the growth of interdisciplinary team science at a research university, and to evaluate its association with research policies, services or institutes.

Detecting and analyzing research communities in longitudinal scientific networks

PubMed Central

Vacca, Raffaele; Kennelly Okraku, Therese; McCarty, Christopher

2017-01-01

A growing body of evidence shows that collaborative teams and communities tend to produce the highest-impact scientific work. This paper proposes a new method to (1) Identify collaborative communities in longitudinal scientific networks, and (2) Evaluate the impact of specific research institutes, services or policies on the interdisciplinary collaboration between these communities. First, we apply community-detection algorithms to cross-sectional scientific collaboration networks and analyze different types of co-membership in the resulting subgroups over time. This analysis summarizes large amounts of longitudinal network data to extract sets of research communities whose members have consistently collaborated or shared collaborators over time. Second, we construct networks of cross-community interactions and estimate Exponential Random Graph Models to predict the formation of interdisciplinary collaborations between different communities. The method is applied to longitudinal data on publication and grant collaborations at the University of Florida. Results show that similar institutional affiliation, spatial proximity, transitivity effects, and use of the same research services predict higher degree of interdisciplinary collaboration between research communities. Our application also illustrates how the identification of research communities in longitudinal data and the analysis of cross-community network formation can be used to measure the growth of interdisciplinary team science at a research university, and to evaluate its association with research policies, services or institutes. PMID:28797047

A Maximum Likelihood Approach to Functional Mapping of Longitudinal Binary Traits

PubMed Central

Wang, Chenguang; Li, Hongying; Wang, Zhong; Wang, Yaqun; Wang, Ningtao; Wang, Zuoheng; Wu, Rongling

2013-01-01

Despite their importance in biology and biomedicine, genetic mapping of binary traits that change over time has not been well explored. In this article, we develop a statistical model for mapping quantitative trait loci (QTLs) that govern longitudinal responses of binary traits. The model is constructed within the maximum likelihood framework by which the association between binary responses is modeled in terms of conditional log odds-ratios. With this parameterization, the maximum likelihood estimates (MLEs) of marginal mean parameters are robust to the misspecification of time dependence. We implement an iterative procedures to obtain the MLEs of QTL genotype-specific parameters that define longitudinal binary responses. The usefulness of the model was validated by analyzing a real example in rice. Simulation studies were performed to investigate the statistical properties of the model, showing that the model has power to identify and map specific QTLs responsible for the temporal pattern of binary traits. PMID:23183762

An introduction to analyzing dichotomous outcomes in a longitudinal setting: a NIDRR traumatic brain injury model systems communication.

PubMed

Pretz, Christopher R; Ketchum, Jessica M; Cuthbert, Jeffery P

2014-01-01

An untapped wealth of temporal information is captured within the Traumatic Brain Injury Model Systems National Database. Utilization of appropriate longitudinal analyses can provide an avenue toward unlocking the value of this information. This article highlights 2 statistical methods used for assessing change over time when examination of noncontinuous outcomes is of interest where this article focuses on investigation of dichotomous responses. Specifically, the intent of this article is to familiarize the rehabilitation community with the application of generalized estimating equations and generalized linear mixed models as used in longitudinal studies. An introduction to each method is provided where similarities and differences between the 2 are discussed. In addition, to reinforce the ideas and concepts embodied in each approach, we highlight each method, using examples based on data from the Rocky Mountain Regional Brain Injury System.

A tutorial on count regression and zero-altered count models for longitudinal substance use data

PubMed Central

Atkins, David C.; Baldwin, Scott A.; Zheng, Cheng; Gallop, Robert J.; Neighbors, Clayton

2012-01-01

Critical research questions in the study of addictive behaviors concern how these behaviors change over time - either as the result of intervention or in naturalistic settings. The combination of count outcomes that are often strongly skewed with many zeroes (e.g., days using, number of total drinks, number of drinking consequences) with repeated assessments (e.g., longitudinal follow-up after intervention or daily diary data) present challenges for data analyses. The current article provides a tutorial on methods for analyzing longitudinal substance use data, focusing on Poisson, zero-inflated, and hurdle mixed models, which are types of hierarchical or multilevel models. Two example datasets are used throughout, focusing on drinking-related consequences following an intervention and daily drinking over the past 30 days, respectively. Both datasets as well as R, SAS, Mplus, Stata, and SPSS code showing how to fit the models are available on a supplemental website. PMID:22905895

Longitudinal Receptive American Sign Language Skills Across a Diverse Deaf Student Body

PubMed Central

2016-01-01

This article presents results of a longitudinal study of receptive American Sign Language (ASL) skills for a large portion of the student body at a residential school for the deaf across four consecutive years. Scores were analyzed by age, gender, parental hearing status, years attending the residential school, and presence of a disability (i.e., deaf with a disability). Years 1 through 4 included the ASL Receptive Skills Test (ASL-RST); Years 2 through 4 also included the Receptive Test of ASL (RT-ASL). Student performance for both measures positively correlated with age; deaf students with deaf parents scored higher than their same-age peers with hearing parents in some instances but not others; and those with a documented disability tended to score lower than their peers without disabilities. These results provide longitudinal findings across a diverse segment of the deaf/hard of hearing residential school population. PMID:26864689

An Overview of Longitudinal Data Analysis Methods for Neurological Research

PubMed Central

Locascio, Joseph J.; Atri, Alireza

2011-01-01

The purpose of this article is to provide a concise, broad and readily accessible overview of longitudinal data analysis methods, aimed to be a practical guide for clinical investigators in neurology. In general, we advise that older, traditional methods, including (1) simple regression of the dependent variable on a time measure, (2) analyzing a single summary subject level number that indexes changes for each subject and (3) a general linear model approach with a fixed-subject effect, should be reserved for quick, simple or preliminary analyses. We advocate the general use of mixed-random and fixed-effect regression models for analyses of most longitudinal clinical studies. Under restrictive situations or to provide validation, we recommend: (1) repeated-measure analysis of covariance (ANCOVA), (2) ANCOVA for two time points, (3) generalized estimating equations and (4) latent growth curve/structural equation models. PMID:22203825

Long-term study of longitudinal dependence in primary particle precipitation in the north Jovian aurora

NASA Technical Reports Server (NTRS)

Livengood, T. A.; Strobel, D. F.; Moos, H. W.

1990-01-01

The wavelength-dependent absorption apparent in IUE spectra of the north Jovian aurora is analyzed to determine the column density of hydrocarbons above the altitude of the FUV auroral emission. Both the magnetotail and torus auroral zone models are considered in estimating zenith angles, with very similar results obtained for both models. It is found that the hydrocarbon column density above the FUV emission displays a consistent dependence on magnetic longitude, with the peak density occurring approximately coincident with the peak in the observed auroral intensity. Two distinct scenarios for the longitude dependence of the column density are discussed. In one, the Jovian upper atmosphere is longitudinally homogeneous, and the variation in optical depth is due to a variation in penetration, and thus energy, of the primary particles. In the other, the energy of the primaries is longitudinally homogeneous, and it is aeronomic properties which change, probably due to auroral heating.

Sieve estimation in semiparametric modeling of longitudinal data with informative observation times.

PubMed

Zhao, Xingqiu; Deng, Shirong; Liu, Li; Liu, Lei

2014-01-01

Analyzing irregularly spaced longitudinal data often involves modeling possibly correlated response and observation processes. In this article, we propose a new class of semiparametric mean models that allows for the interaction between the observation history and covariates, leaving patterns of the observation process to be arbitrary. For inference on the regression parameters and the baseline mean function, a spline-based least squares estimation approach is proposed. The consistency, rate of convergence, and asymptotic normality of the proposed estimators are established. Our new approach is different from the usual approaches relying on the model specification of the observation scheme, and it can be easily used for predicting the longitudinal response. Simulation studies demonstrate that the proposed inference procedure performs well and is more robust. The analyses of bladder tumor data and medical cost data are presented to illustrate the proposed method.

A comparison of longitudinal and transverse approaches to ultrasound-guided axillary vein cannulation by experienced operators

PubMed Central

He, Yi-Zhou; Zhong, Ming; Wu, Wei; Song, Jie-Qiong

2017-01-01

Background The axillary vein is an easily accessible vessel that can be used for ultrasound-guided central vascular access and offers an alternative to the internal jugular and subclavian veins. The objective of this study was to identify which transducer orientation, longitudinal or transverse, is better for imaging the axillary vein with ultrasound. Methods We analyzed 236 patients who had undergone central venous cannulation of axillary vein in this retrospective study. Patients were divided into two groups, the longitudinal approach group (n=120) and transverse approach group (n=116). Recorded the one-attempt success rate, operation time, arterial puncture rate and pneumothorax rate. We perform chest radiography to confirm pneumothorax on all patients. We compared the one-attempt success rate, operation time, arterial puncture rate and pneumothorax rate between the two groups. Results The two groups were comparable with clinical characters of patients. The overall success rates of the longitudinal group and the transverse group were both 100%. The rate of one-attempt success in the longitudinal approach group is higher than the transverse approach group (91.7% vs. 82.8%, P=0.040). The transverse approach group had shorter operation time than the longitudinal group (184.7±8.1 vs. 287.5±19.6 seconds, P=0.000). The two groups had lower postoperative complications. Arterial puncture occurred in 1 of 120 longitudinal and 2 of 116 transverse attempts and this difference was no significant (P=0.541). No pneumothorax occurred in the two groups. Conclusions The longitudinal approach during ultrasound-guided axillary vein cannulation is associated with greater one-attempt success rate compared with the transverse approach by experienced operators. The transverse approach has shorter operation time. The two groups have lower postoperative complications and are comparable with pneumothorax and arterial puncture. PMID:28523170

Longitudinal phase space tomography using a booster cavity at PITZ

NASA Astrophysics Data System (ADS)

Malyutin, D.; Gross, M.; Isaev, I.; Khojoyan, M.; Kourkafas, G.; Krasilnikov, M.; Marchetti, B.; Otevrel, M.; Stephan, F.; Vashchenko, G.

2017-11-01

The knowledge of the longitudinal phase space (LPS) of electron beams is of great importance for optimizing the performance of high brightness photo injectors. To get the longitudinal phase space of an electron bunch in a linear accelerator a tomographic technique can be used. The method is based on measurements of the bunch momentum spectra while varying the bunch energy chirp. The energy chirp can be varied by one of the RF accelerating structures in the accelerator and the resulting momentum distribution can be measured with a dipole spectrometer further downstream. As a result, the longitudinal phase space can be reconstructed. Application of the tomographic technique for reconstruction of the longitudinal phase space is introduced in detail in this paper. Measurement results from the PITZ facility are shown and analyzed.

School Board Policy As a Control Mechanism in Curriculum Challenges.

ERIC Educational Resources Information Center

Adler, Louise

1993-01-01

This journal article examines how school board policies are used to control the controversies that often surround curriculum challenges. Specific key provisions of model policies and actual policies from California are analyzed to suggest ideal policy provisions. In a longitudinal study, over 42 percent of the 1,000-plus school districts in…

College Choice in America.

ERIC Educational Resources Information Center

Manski, Charles F.; And Others

The processes of choosing a college and being accepted by a college are analyzed, based on data on nearly 23,000 seniors from more than 1,300 high schools from the National Longitudinal Study of the Class of 1972. Econometric modeling and descriptive statistics are provided on: student behavior in selecting a college, choosing school/nonschool…

Predictors of Access to Sex Education for Children with Intellectual Disabilities in Public Schools

ERIC Educational Resources Information Center

Barnard-Brak, Lucy; Schmidt, Marcelo; Chesnut, Steven; Wei, Tianlan; Richman, David

2014-01-01

Data from the National Longitudinal Transition Study-2 (SRI International, 2002) were analyzed to identify variables that predicted whether individuals with intellectual disability (ID) received sex education in public schools across the United States. Results suggested that individuals receiving special education services without ID were only…

Changing the Attitudes of Pre-Service Teachers toward Content Literacy Stategies

ERIC Educational Resources Information Center

Warren-Kring, Bonnie Z.; Warren, Grace A.

2013-01-01

The purpose of this research was to study the impact of an adolescent literacy education course on content area education students' attitudes toward implementing adolescent literacy strategies within their content lessons. Longitudinal data were gathered over five years and then analyzed. The researcher documented changes in the attitudes of the…

An Analysis of Primary School Dropout Patterns in Honduras

ERIC Educational Resources Information Center

Sekiya, Takeshi; Ashida, Akemi

2017-01-01

This study hypothesized that repeating a grade is one reason why Honduran primary students drop out of school but not the main reason. Using longitudinal data, we analyzed student enrollment patterns up until students left school. The results revealed that many students dropped out suddenly without having previously repeated a grade, although many…

CORRESPONDENCE OF STABLE ISOTOPE AND GUT CONTENTS ANALYSES IN DETERMINING TROPHIC POSITION OF STREAM FISHES

EPA Science Inventory

It is generally accepted that both stable isotope analysis (SIA) and gut contents analysis (GCA) be used in food web studies; however, few researchers have analyzed these data in concert. We utilized SIA and GCA to determine if longitudinal and seasonal variation in diet affects...

Problem Behavior and Developmental Tasks in Adolescents with Visual Impairment and Sighted Peers

ERIC Educational Resources Information Center

Pfeiffer, Jens P.; Pinquart, Martin

2013-01-01

This longitudinal study analyzed associations of problem behavior with the attainment of developmental tasks in 133 adolescents with visual impairment and 449 sighted peers. Higher levels of initial problem behavior predicted less progress in the attainment of developmental tasks at the one-year follow-up only in sighted adolescents. This…

Parental Divorce and Union Disruption among Young Adults in Sweden

ERIC Educational Resources Information Center

Gahler, Michael; Hong, Ying; Bernhardt, Eva

2009-01-01

This article analyzes the impact of parental divorce on the disruption of marital and nonmarital unions among young adults in Sweden, using longitudinal data from repeated mail questionnaire surveys (1999 and 2003) with 1,321 respondents (aged 26, 30, and 34 in 2003). The study takes into account several possible mechanisms governing the…

Review of Mobile Learning Trends 2010-2015: A Meta-Analysis

ERIC Educational Resources Information Center

Chee, Ken Nee; Yahaya, Noraffandy; Ibrahim, Nor Hasniza; Hasan, Mohamed Noor

2017-01-01

This study examined the longitudinal trends of mobile learning (M-Learning) research using text mining techniques in a more comprehensive manner. One hundred and forty four (144) refereed journal articles were retrieved and analyzed from the Social Science Citation Index database selected from top six major educational technology-based learning…

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…

Parent-Child Relationship Trajectories during Adolescence: Longitudinal Associations with Romantic Outcomes in Emerging Adulthood

ERIC Educational Resources Information Center

Seiffge-Krenke, Inge; Overbeek, Geertjan; Vermulst, Ad

2010-01-01

This study examined the developmental trajectories of parent-child relationships in adolescence, especially with respect to changes in support levels and negativity, and analyzed if and how these trajectories were associated with the subsequent quality of romantic relationships in young adulthood. A sample of 145 German subjects was followed…

Teacher Self-Efficacy as a Long-Term Predictor of Instructional Quality in the Classroom

ERIC Educational Resources Information Center

Künsting, Josef; Neuber, Victoria; Lipowsky, Frank

2016-01-01

In this longitudinal study, we examined teachers' self-efficacy as a long-term predictor of their mastery goal orientation and three dimensions of instructional quality: supportive classroom climate, effective classroom management, and cognitive activation. Mastery goal orientation was also analyzed as a predictor of instructional quality.…

New Clues to Reaching Very Young Children and Families in Rural America

ERIC Educational Resources Information Center

Grace, Cathy; Shores, Elizabeth F.; Zaslow, Martha; Brown, Brett; Aufseeser, Dena

2006-01-01

The National Center for Rural Early Childhood Learning Initiatives (Rural Early Childhood), a research program of the Mississippi State University Early Childhood Institute, and Child Trends analyzed data from two nationally representative samples of young children being followed in the Early Childhood Longitudinal Study by the National Center for…

Effects of Three Interventions on the Reading Skills of Children with Reading Disabilities in Grade 2

ERIC Educational Resources Information Center

Gustafson, Stefan; Falth, Linda; Svensson, Idor; Tjus, Tomas; Heimann, Mikael

2011-01-01

In a longitudinal intervention study, the effects of three intervention strategies on the reading skills of children with reading disabilities in Grade 2 were analyzed. The interventions consisted of computerized training programs: One bottom-up intervention aimed at improving word decoding skills and phonological abilities, the second…

The Relationship between Teacher Regard and College Attendance Expectations: Socioeconomic and Racial-Ethnic Disparities

ERIC Educational Resources Information Center

Pinchak, Nicolo P.

2018-01-01

This study uses data from wave one of the National Longitudinal Survey of Adolescent to Adult Health to analyze the relationship between middle and secondary school students' perceptions of their teachers, or "teacher regard," and students' expectations for college attendance. Variation in this relationship is further examined by…

Layering Literacies and Contemporary Learning

ERIC Educational Resources Information Center

Abrams, Sandra Schamroth; Russo, Michael P.

2015-01-01

This article explores how adolescents layer literacies in and outside school. Findings from a longitudinal study of gaming in a public library, as well as data related to the use of Portal 2 in a New York City middle school classroom, reveal how the students created, showcased, analyzed, and experimented with online and offline artifacts and…

Self versus Others' Perception of Youths' Mental Health

ERIC Educational Resources Information Center

Viviano, Thomas A.

2010-01-01

Data was analyzed in the National Longitudinal Survey Study from 1997 specifically relating to questions regarding depression in youth. In the analysis it was found that how the respondent defined their own depression and poor mental health was different than the perceptions about their mental health from those that live with them in the same…

Does Family Experience Influence Political Beliefs? Relation between Interparental Conflict Perceptions and Political Efficacy in Late Adolescence

ERIC Educational Resources Information Center

Serek, Jan; Lacinova, Lenka; Macek, Petr

2012-01-01

The study examined the relation between adolescents' interparental conflict perceptions and their political efficacy regarding local issues. Longitudinal data (age 15 and 17) from 444 adolescents were analyzed using structural equation modeling. Results showed that young people experiencing frequent interparental conflict reported an increase in…

Success after Failure: Academic Effects and Psychological Implications of Early Universal Algebra Policies

ERIC Educational Resources Information Center

Howard, Keith A.; Scott, Allison; Romero, Martin; Saddler, Derrick

2015-01-01

In this article, the authors use the High School Longitudinal Study 2009 (HSLS:09) national database to analyze the relationships between algebra failure, subsequent performance, motivation, and college readiness. Students who failed eighth-grade Algebra I did not differ significantly in mathematics proficiency from those who passed lower-level…

Social Origins and Attitudinal Effects on Educational Status Attainment.

ERIC Educational Resources Information Center

Thomas, John K.; And Others

Research objectives were to present and analyze a causal model of educational attainment and to include with parental socioeconomic status the number of siblings as an intervening social origin variable impacting on attitudes and attainment. Data were obtained from a three-wave longitudinal study (1966, 1968, and 1972) of 221 white nonmetropolitan…

Is Prosodic Production Driven by Lexical Development? Longitudinal Evidence from Babble and Words

ERIC Educational Resources Information Center

De Clerck, Ilke; Pettinato, Michele; Verhoeven, Jo; Gillis, Steven

2017-01-01

This study investigated the relation between lexical development and the production of prosodic prominence in disyllabic babble and words. Monthly recordings from nine typically developing Belgian-Dutch-speaking infants were analyzed from the onset of babbling until a cumulative vocabulary of 200 words was reached. The differentiation between the…

Developmental Patterns in Marital Satisfaction: Another Look at Covenant Marriage

ERIC Educational Resources Information Center

DeMaris, Alfred; Sanchez, Laura A.; Krivickas, Kristi

2012-01-01

This study investigated differences in the trajectory of marital satisfaction in the first 7 years between couples in covenant versus standard marriages. The authors analyzed data on 707 Louisiana marriages from the Marriage Matters Panel Survey of Newlywed Couples, 1998-2004, using multivariate longitudinal growth modeling. When the sample was…

Examining External and Internal Poverty as Antecedents of Teen Pregnancy

ERIC Educational Resources Information Center

Young, Tamera; Turner, Jean; Denny, George; Young, Michael

2004-01-01

Objectives: To identify antecedents of teen pregnancy. Methods: Data from the National Education Longitudinal Study were analyzed. This data set allowed us to identify eighth-grade antecedents of teen pregnancy/childbearing. Results: The variables that were found to be most predictive of later pregnancy were reflective of internal poverty (locus…

Longitudinal Study of Children's Oral Reading Behavior. Final Report.

ERIC Educational Resources Information Center

Goodman, Yetta M.

Four Negro children's (two average and two slow readers) oral reading was taped at eight regular intervals during their second and third year of reading instruction in order to analyze their oral reading miscues and to discover any developmental changes. Retelling of stories read was also taped to measure comprehension. The miscues were analyzed…

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.…

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…

Longitudinal analysis on utilization of medical document management system in a hospital with EPR implementation.

PubMed

Kuwata, Shigeki; Yamada, Hitomi; Park, Keunsik

2011-01-01

Document management systems (DMS) have widespread in major hospitals in Japan as a platform to digitize the paper-based records being out of coverage by EPR. This study aimed to examine longitudinal trends of actual use of DMS in a hospital in which EPR had been in operation, which would be conducive to planning the further information management system in the hospital. Degrees of utilization of electronic documents and templates with DMS were analyzed based on data extracted from a university-affiliated hospital with EPR. As a result, it was found that the number of electronic documents as well as scanned documents circulating at the hospital tended to increase. The result indicated that replacement of paper-based documents with electronic documents did not occur. Therefore it was anticipated that the need for DMS would continue to increase in the hospital. The methods used this study to analyze the trend of DMS utilization would be applicable to other hospitals with with a variety of DMS implementation, such as electronic storage by scanning documents or paper preservation that is compatible with EPR.

Albumin, Hemoglobin, and the Trajectory of Cognitive Function in Community-Dwelling Older Japanese: A 13-Year Longitudinal Study.

PubMed

Murayama, H; Shinkai, S; Nishi, M; Taniguchi, Y; Amano, H; Seino, S; Yokoyama, Y; Yoshida, H; Fujiwara, Y; Ito, H

2017-01-01

Cognitive function can substantially decline over a long period, and understanding the trajectory of cognitive function is important. However, little is known about the linkage between nutritional biomarkers and long-term cognitive change. We analyzed 13-year longitudinal data for older Japanese to examine the associations of serum albumin and hemoglobin levels with the trajectory of cognitive function. Longitudinal study. Community-based. A total of 1,744 community-dwelling adults aged 65 years or older who participated in annual health examinations in Kusatsu town, Gunma Prefecture, Japan, from 2002-2014. Cognitive function was assessed annually by the Mini-Mental State Examination (MMSE). Albumin and hemoglobin levels at baseline (the year when a respondent first participated in the health examination) were divided into quartiles. Hierarchical linear modeling was used to analyze intrapersonal and interpersonal differences in cognitive function. Participants' MMSE scores decreased at an accelerated rate over the 13-year period. Participants with the lowest baseline albumin level (below the first quartile line) showed a greater accelerated decline in MMSE scores over time, compared with those with the highest level (above the third quartile line). Moreover, MMSE scores in participants with a lower hemoglobin level and lower MMSE score at baseline tended to decline faster over time at an accelerated rate. These findings yield new insights about the complex and diverse roles of these nutritional biomarkers on the trajectory of cognitive function in old age.

Longitudinal-bending mode micromotor using multilayer piezoelectric actuator.

PubMed

Yao, K; Koc, B; Uchino, K

2001-07-01

Longitudinal-bending mode ultrasonic motors with a diameter of 3 mm were fabricated using stacked multilayer piezoelectric actuators, which were self-developed from hard lead zirconate titanate (PZT) ceramic. A bending vibration was converted from a longitudinal vibration with a longitudinal-bending coupler. The motors could be bidirectionally operated by changing driving frequency. Their starting and braking torque were analyzed based on the transient velocity response. With a load of moment of inertia 2.5 x 10(-7) kgm2, the motor showed a maximum starting torque of 127.5 microNm. The braking torque proved to be a constant independent on the motor's driving conditions and was roughly equivalent to the maximum starting torque achievable with our micromotors.

Multivariate mixed linear model analysis of longitudinal data: an information-rich statistical technique for analyzing disease resistance data

USDA-ARS?s Scientific Manuscript database

The mixed linear model (MLM) is currently among the most advanced and flexible statistical modeling techniques and its use in tackling problems in plant pathology has begun surfacing in the literature. The longitudinal MLM is a multivariate extension that handles repeatedly measured data, such as r...

A varying-coefficient method for analyzing longitudinal clinical trials data with nonignorable dropout

PubMed Central

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

How Clear and Organized Classroom Instruction and Deep Approaches to Learning Affect Growth in Critical Thinking and Need for Cognition

ERIC Educational Resources Information Center

Wang, Jui-Sheng; Pascarella, Ernest T.; Nelson Laird, Thomas F.; Ribera, Amy K.

2015-01-01

In this study the authors analyze longitudinal student survey data from the 17-institution Wabash National Study of Liberal Arts Education (WNS) to determine the extent that the influence of overall exposure to clear and organized instruction on four-year growth in two measures of cognitive development is mediated by student use of deep approaches…

Patterns and Sources of Continuity and Change of Energetic and Temporal Aspects of Temperament in Adulthood: A Longitudinal Twin Study of Self- and Peer Reports

ERIC Educational Resources Information Center

Kandler, Christian; Riemann, Rainer; Angleitner, Alois

2013-01-01

This study investigated the mean-level and individual-level trends as well as the genetic and environmental sources of rank-order continuity and change in temperament traits ("Briskness, Perseveration, Sensory Sensitivity, Emotional Reactivity, Endurance, and Activity"). We analyzed self-reports and peer ratings from 2 adult age groups…

Does Active Management Benefit Endowment Returns? An Analysis of the NACUBO-Commonfund Study of Endowments (NCSE) Data

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…

The Adjustment of New Recruits to Military Life in the Chinese Army: The Longitudinal Predictive Power of MMPI-2

ERIC Educational Resources Information Center

Xiao, Lijun; Han, Jing; Han, Jian

2011-01-01

In this article, the authors present the findings of two studies analyzing new recruits' adjustment to army life in the Chinese military. In the first exploratory study, we developed a scale to measure new recruits' adjustment to military life, and found that new soldiers' adaptation could be divided into two distinct types: interpersonal…

Examining Academic Variables Affecting the Persistence and Attainment of Black Male Collegians: A Focus on Academic Performance and Integration in the Two-Year College

ERIC Educational Resources Information Center

Wood, J. Luke

2014-01-01

The purpose of this study was to investigate the effect of academic variables (e.g., grade point average, major change, informal meetings with faculty) on six year persistence and attainment among black male students in community colleges. Data was collected from the Beginning Postsecondary Students Longitudinal Study and was analyzed using…

Defying Statistics or "Latch-key Children in the Late '80s: Family Composition, Working Mothers, and After School Supervision."

ERIC Educational Resources Information Center

Muller, Chandra; And Others

This study explored the effects of after-school supervision on 8th graders' academic performance. Data from the National Educational Longitudinal Study of 1988 relating to a total sample size of 20,491 students (after exclusions) in 802 public and 233 private schools were analyzed. The analysis indicated that parents do not discriminate between…

Attention Interchanges at Story-Time: A Case Study from a Deaf and Hearing Twin Pair Acquiring Swedish Sign Language in Their Deaf Family

ERIC Educational Resources Information Center

Cramer-Wolrath, Emelie

2012-01-01

This case study longitudinally analyzes and describes the changes of attentional expressions in interchanges between a pair of fraternal twins, 1 deaf and 1 hearing, from the age of 10-40 months, and their Deaf family members. The video-observed attentional expressions of initiating and reestablishing interchange were grouped in 5 functional…

A Study of the Effectiveness of Two Alternative Middle Schools: How Prepared Are Students for High School Success?

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…

Changes in the Black-White Test score Gap in the Elementary School Grades. CSE Report 715

ERIC Educational Resources Information Center

Koretz, Daniel; Kim, Young-Suk

2007-01-01

In a pair of recent studies, Fryer and Levitt (2004a, 2004b) analyzed the Early Childhood Longitudinal Study--Kindergarten Cohort (ECLS-K) to explore the characteristics of the Black-White test score gap in young children. They found that the gap grew markedly between kindergarten and the third grade and that they could predict the gap from…

Peers and Academic Achievement: A Longitudinal Study on Selection and Socialization Effects of In-Class Friends

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.…

I-States-as-Objects-Analysis (ISOA): Extensions of an Approach to Studying Short-Term Developmental Processes by Analyzing Typical Patterns

ERIC Educational Resources Information Center

Bergman, Lars R.; Nurmi, Jari-Erik; von Eye, Alexander A.

2012-01-01

I-states-as-objects-analysis (ISOA) is a person-oriented methodology for studying short-term developmental stability and change in patterns of variable values. ISOA is based on longitudinal data with the same set of variables measured at all measurement occasions. A key concept is the "i-state," defined as a person's pattern of variable…

Teens and Their Parents in the 21st Century: An Examination of Trends in Teen Behavior and the Role of Parental Involvement.

ERIC Educational Resources Information Center

Council of Economic Advisers, Washington, DC.

This report by the Council of Economic Advisers analyzes key trends in teen behavior, and investigates the role of parents' involvement in their teenagers' lives. The report uses data from the National Longitudinal Study of Adolescent Health, a study of a nationally representative sample of seventh through twelfth graders, to examine the…

The Relationship between Parental Involvement, Self-Regulated Learning, and Reading Achievement of Fifth Graders: A Path Analysis Using the ECLS-K Database

ERIC Educational Resources Information Center

Xu, Min; Kushner Benson, Susan N.; Mudrey-Camino, Renee; Steiner, Richard P.

2010-01-01

This study examined the relationship between parental involvement, self-regulated learning (SRL), and reading achievement through analyzing the fifth grade data from the Early Childhood Longitudinal Study, Kindergarten Class of 1998-1999 (ECLS-K). The results identified six dimensions of parental involvement that are likely to foster SRL of fifth…

Longitudinal Analysis of Student Performance between Host and Cooperating College Learners in the Dental Hygiene Program at Northcentral Technical College in Wausau, Wisconsin.

ERIC Educational Resources Information Center

Olmsted, Jodi L.

The academic performance of students enrolled in a distance education dental hygiene program at Northcentral Technical College (NTC) in Wausau, Wisconsin, was analyzed in a comparative, quasi-experimental study. The study sample consisted of five cohorts of program graduates (students graduating in 1997-2001). The experiment groups were divided…

Nonlinear mechanisms of two-dimensional wave-wave transformations in the initially coupled acoustic structure

NASA Astrophysics Data System (ADS)

Vorotnikov, K.; Starosvetsky, Y.

2018-01-01

The present study concerns two-dimensional nonlinear mechanisms of bidirectional and unidirectional channeling of longitudinal and shear waves emerging in the locally resonant acoustic structure. The system under consideration comprises an oscillatory chain of the axially coupled masses. Each mass of the chain is subject to the local linear potential along the lateral direction and incorporates the lightweight internal rotator. In the present work, we demonstrate the emergence of special resonant regimes of complete bi- and unidirectional transitions between the longitudinal and the shear waves of the locally resonant chain. These regimes are manifested by the two-dimensional energy channeling between the longitudinal and the shear traveling waves in the recurrent as well as the irreversible fashion. We show that the spatial control of the two dimensional energy flow between the longitudinal and the shear waves is solely governed by the motion of the internal rotators. Nonlinear analysis of the regimes of a bidirectional wave channeling unveils their global bifurcation structure and predicts the zones of their spontaneous transitions from a complete bi-directional wave channeling to the one-directional entrapment. An additional regime of a complete irreversible resonant transformation of the longitudinal wave into a shear wave is analyzed in the study. The intrinsic mechanism governing the unidirectional wave reorientation is described analytically. The results of the analysis of both mechanisms are substantiated by the numerical simulations of the full model and are found to be in a good agreement.

Lesion registration for longitudinal disease tracking in an imaging informatics-based multiple sclerosis eFolder

NASA Astrophysics Data System (ADS)

Ma, Kevin; Liu, Joseph; Zhang, Xuejun; Lerner, Alex; Shiroishi, Mark; Amezcua, Lilyana; Liu, Brent

2016-03-01

We have designed and developed a multiple sclerosis eFolder system for patient data storage, image viewing, and automatic lesion quantification results stored in DICOM-SR format. The web-based system aims to be integrated in DICOM-compliant clinical and research environments to aid clinicians in patient treatments and data analysis. The system needs to quantify lesion volumes, identify and register lesion locations to track shifts in volume and quantity of lesions in a longitudinal study. In order to perform lesion registration, we have developed a brain warping and normalizing methodology using Statistical Parametric Mapping (SPM) MATLAB toolkit for brain MRI. Patients' brain MR images are processed via SPM's normalization processes, and the brain images are analyzed and warped according to the tissue probability map. Lesion identification and contouring are completed by neuroradiologists, and lesion volume quantification is completed by the eFolder's CAD program. Lesion comparison results in longitudinal studies show key growth and active regions. The results display successful lesion registration and tracking over a longitudinal study. Lesion change results are graphically represented in the web-based user interface, and users are able to correlate patient progress and changes in the MRI images. The completed lesion and disease tracking tool would enable the eFolder to provide complete patient profiles, improve the efficiency of patient care, and perform comprehensive data analysis through an integrated imaging informatics system.

[Impact of Different Types of Fathers on Family Climate in Young Adulthood: A Multi-perspective Longitudinal Study on 14 to 27 Year Olds and their Fathers].

PubMed

Escher, Fabian J; Seiffge-Krenke, Inge

2018-01-01

Impact of Different Types of Fathers on Family Climate in Young Adulthood: A Multi-perspective Longitudinal Study on 14 to 27 Year Olds and their Fathers In a 13 year longitudinal study, the influence of three types of fathers on the family climate was analyzed. In a sample of 213 subjects, their 169 fathers and their 210 mothers, the family environment ( Family Environment Scales) was examined when the subjects were young adults (M = 26.89, SD = 1.32). The results of the study point to significant changes in family climate in those young adults who described their father as increasingly negative (N = 28) or distant (N = 11) when in adolescence. These two groups showed a more negative family environment and greater differences between the perspectives of fathers and their young adult children than the group of young adults who described their father as normative (N = 174) when in adolescence. The highest discrepancies were described by young adults with a negative relationship with their father in adolescence. The findings show a long lasting importance of father-child interactions in adolescence.

Analysis on Coupled Vibration of a Radially Polarized Piezoelectric Cylindrical Transducer

PubMed Central

Xu, Jie; Lin, Shuyu; Ma, Yan; Tang, Yifan

2017-01-01

Coupled vibration of a radially polarized piezoelectric cylindrical transducer is analyzed with the mechanical coupling coefficient method. The method has been utilized to analyze the metal cylindrical transducer and the axially polarized piezoelectric cylindrical transducer. In this method, the mechanical coupling coefficient is introduced and defined as the stress ratio in different directions. Coupled vibration of the cylindrical transducer is regarded as the interaction of the plane radial vibration of a ring and the longitudinal vibration of a tube. For the radially polarized piezoelectric cylindrical transducer, the radial and longitudinal electric admittances as functions of mechanical coupling coefficients and angular frequencies are derived, respectively. The resonance frequency equations are obtained. The dependence of resonance frequency and mechanical coupling coefficient on aspect ratio is studied. Vibrational distributions on the surfaces of the cylindrical transducer are presented with experimental measurement. On the support of experiments, this work is verified and provides a theoretical foundation for the analysis and design of the radially polarized piezoelectric cylindrical transducer. PMID:29292785

Longitudinal Relations Among Negative Affect, Substance Use and Peer Deviance During the Transition from Middle to Late Adolescence

PubMed Central

Mason, W. Alex; Hitchings, Julia E.; Spoth, Richard L.

2010-01-01

The transition from middle to late adolescence brings challenges that increase risk for emotional, behavioral, and social problems. The nature of the associations among these types of problems is poorly understood. This National Institute on Drug Abuse-funded study examined longitudinal relations among negative affect, substance use, and peer deviance from ages 16 to 18 years. Multiwave youth and parent questionnaire data collected from 429 6thgraders (222 girls) and their families residing in the rural Midwestern United States and recruited in 1993 were analyzed via structural equation modeling. Consistent with the self-medication hypothesis, negative affect statistically predicted increased substance use over time. Implications for theory and prevention are discussed and the study's limitations are noted. PMID:19544145

A nonparametric smoothing method for assessing GEE models with longitudinal binary data.

PubMed

Lin, Kuo-Chin; Chen, Yi-Ju; Shyr, Yu

2008-09-30

Studies involving longitudinal binary responses are widely applied in the health and biomedical sciences research and frequently analyzed by generalized estimating equations (GEE) method. This article proposes an alternative goodness-of-fit test based on the nonparametric smoothing approach for assessing the adequacy of GEE fitted models, which can be regarded as an extension of the goodness-of-fit test of le Cessie and van Houwelingen (Biometrics 1991; 47:1267-1282). The expectation and approximate variance of the proposed test statistic are derived. The asymptotic distribution of the proposed test statistic in terms of a scaled chi-squared distribution and the power performance of the proposed test are discussed by simulation studies. The testing procedure is demonstrated by two real data. Copyright (c) 2008 John Wiley & Sons, Ltd.

Parental perceptions of siblings' grieving after a childhood cancer death: a longitudinal study.

PubMed

Barrera, Maru; Alam, Rifat; D'Agostino, Norma Mammone; Nicholas, David B; Schneiderman, Gerald

2013-01-01

We investigated longitudinally parental perceptions of siblings' bereavement after childhood cancer death. Parents were interviewed 6 months (n = 25) and 18 months (n = 75) post-death. Data are analyzed combined and over time. The following themes emerged: (a) expression of grief missing deceased child (verbally, crying), behavioral problems, difficulty understanding the meaning of death (pre-schoolers), and avoiding talking with parents about feelings (adolescents); (b) what helps siblings grief moving on, talking about deceased child and social support; (c) relationship with parents improved for most siblings; and (d) bond with deceased sibling: pretend-play (preschoolers), dreaming, and career choices (adolescents). Over time, themes reflected stability and change.

Health impact: longitudinal analysis of employment at middle and old age in Mexico

PubMed Central

GONZÁLEZ-GONZÁLEZ, César; WONG, Rebeca

2015-01-01

We use longitudinal data from the Mexican Health and Aging Study to analyze the relationship between health and labor force participation of population aged 50 years and older in Mexico. The results confirm that health, measured through chronic diseases and difficulty to perform activities of daily living, has a powerful influence on labor force participation. We also find important differences by gender; hypertension and diabetes have effects in both, men and women; heart disease and stroke only in men. We provide concrete evidence on economic participation and highlight the importance of public policies to create adequate jobs for the population at middle and old age. PMID:25722646

Digital divide 2.0: the role of social networking sites in seeking health information online from a longitudinal perspective.

PubMed

Feng, Yang; Xie, Wenjing

2015-01-01

Adopting a longitudinal angle, this study analyzed data from the Pew Internet's Health Tracking Survey in 2006, 2008, and 2010 to identify potential communication inequalities in social networking site use. Results showed that with the growing role of social networking site use in predicting people's likelihood of seeking health information online, the socioeconomic and demographic factors that contributed to the disparities in social networking site use could also lead to disparities in seeking health information online. Also, results indicated that people are more likely to seek heath-related information online if they or their close family or friends have a chronic disease situation.

Longitudinal Change in Telomere Length and the Chronic Stress Response in a Randomized Pilot Biobehavioral Clinical Study: Implications for Cancer Prevention

PubMed Central

Biegler, Kelly A.; Anderson, Amanda K. L.; Wenzel, Lari B.; Osann, Kathryn; Nelson, Edward L.

2015-01-01

Shortened telomere length is associated with increased cancer incidence and mortality. Populations experiencing chronic stress have accelerated telomere shortening. In this exploratory study, we examined associations between longitudinal changes in patient reported outcomes (PRO) of psychologic distress and peripheral blood mononuclear cell (PBMC) telomere length to test the hypothesis that modulation of the chronic stress response would also modulate telomere dynamics. Archived PBMC specimens (N = 22) were analyzed from a completed and reported randomized, longitudinal trial that showed a psychosocial telephone counseling intervention improved quality of life (QOL) and modulated stress-associated biomarkers in cervical cancer survivors. PROs and biospecimens were collected at baseline and 4 months postenrollment. Telomere length of archived PBMCs was evaluated using the flow-FISH assay. Longitudinal changes in psychologic distress, measured by the Brief Symptom Inventory-18, were significantly associated with increased telomere length within the CD14+ (monocyte) population (r = 0.46, P = 0.043); a similar trend was observed for the CD14− population. Longitudinal changes in telomere length of the CD14− subset, primarily T lymphocytes, were associated with longitudinal increases in the naive T-cell population (r = 0.49, P = 0.052). Alterations in the chronic stress response were associated with modulation of telomere length in PBMCs, with evidence for mobilization of “younger” cells from progenitor populations. These data provide preliminary support for the (i) capacity to modulate the chronic stress response and the associated accelerated telomere shortening, (ii) inclusion of telomere length in the biobehavioral paradigm, and (iii) potential link between the chronic stress response and biologic mechanisms responsible for genomic integrity and carcinogenesis. PMID:22827974

Maturational Patterns of Systolic Ventricular Deformation Mechanics by Two-Dimensional Speckle-Tracking Echocardiography in Preterm Infants over the First Year of Age.

PubMed

Levy, Philip T; El-Khuffash, Afif; Patel, Meghna D; Breatnach, Colm R; James, Adam T; Sanchez, Aura A; Abuchabe, Cristina; Rogal, Sarah R; Holland, Mark R; McNamara, Patrick J; Jain, Amish; Franklin, Orla; Mertens, Luc; Hamvas, Aaron; Singh, Gautam K

2017-07-01

The aim of this study was to determine the maturational changes in systolic ventricular strain mechanics by two-dimensional speckle-tracking echocardiography in extremely preterm neonates from birth to 1 year of age and discern the impact of common cardiopulmonary abnormalities on the deformation measures. In a prospective multicenter study of 239 extremely preterm infants (<29 weeks gestation at birth), left ventricular (LV) global longitudinal strain (GLS) and global longitudinal systolic strain rate (GLSRs), interventricular septal wall (IVS) GLS and GLSRs, right ventricular (RV) free wall longitudinal strain and strain rate, and segmental longitudinal strain in the RV free wall, LV free wall, and IVS were serially measured on days 1, 2, and 5 to 7, at 32 and 36 weeks postmenstrual age, and at 1 year corrected age (CA). Premature infants who developed bronchopulmonary dysplasia or had echocardiographic findings of pulmonary hypertension were analyzed separately. In uncomplicated preterm infants (n = 103 [48%]), LV GLS and GLSRs remained unchanged from days 5 to 7 to 1 year CA (P = .60 and P = .59). RV free wall longitudinal strain, RV free wall longitudinal strain rate, and IVS GLS and GLSRs significantly increased over the same time period (P < .01 for all measures). A significant base-to-apex (highest to lowest) segmental longitudinal strain gradient (P < .01) was seen in the RV free wall and a reverse apex-to-base gradient (P < .01) in the LV free wall. In infants with bronchopulmonary dysplasia and/or pulmonary hypertension (n = 119 [51%]), RV free wall longitudinal strain and IVS GLS were significantly lower (P < .01), LV GLS and GLSRs were similar (P = .56), and IVS segmental longitudinal strain persisted as an RV-dominant base-to-apex gradient from 32 weeks postmenstrual age to 1 year CA. This study tracks the maturational patterns of global and regional deformation by two-dimensional speckle-tracking echocardiography in extremely preterm infants from birth to 1 year CA. The maturational patterns are ventricular specific. Bronchopulmonary dysplasia and pulmonary hypertension leave a negative impact on RV and IVS strain, while LV strain remains stable. Copyright © 2017 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.

SwathProfiler and NProfiler: Two new ArcGIS Add-ins for the automatic extraction of swath and normalized river profiles

NASA Astrophysics Data System (ADS)

Pérez-Peña, J. V.; Al-Awabdeh, M.; Azañón, J. M.; Galve, J. P.; Booth-Rea, G.; Notti, D.

2017-07-01

The present-day great availability of high-resolution Digital Elevation Models has improved tectonic geomorphology analyses in their methodological aspects and geological meaning. Analyses based on topographic profiles are valuable to explore the short and long-term landscape response to tectonic activity and climate changes. Swath and river longitudinal profiles are two of the most used analysis to explore the long and short-term landscape responses. Most of these morphometric analyses are conducted in GIS software, which have become standard tools for analyzing drainage network metrics. In this work we present two ArcGIS Add-Ins to automatically delineate swath and normalized river profiles. Both tools are programmed in Visual Basic . NET and use ArcObjects library-architecture to access directly to vector and raster data. The SwathProfiler Add-In allows analyzing the topography within a swath or band by representing maximum-minimum-mean elevations, first and third quartile, local relief and hypsometry. We have defined a new transverse hypsometric integral index (THi) that analyzes hypsometry along the swath and offer valuable information in these kind of graphics. The NProfiler Add-In allows representing longitudinal normalized river profiles and their related morphometric indexes as normalized concavity (CT), maximum concavity (Cmax) and length of maximum concavity (Lmax). Both tools facilitate the spatial analysis of topography and drainage networks directly in a GIS environment as ArcMap and provide graphical outputs. To illustrate how these tools work, we analyzed two study areas, the Sierra Alhamilla mountain range (Betic Cordillera, SE Spain) and the Eastern margin of the Dead Sea (Jordan). The first study area has been recently studied from a morphotectonic perspective and these new tools can show an added value to the previous studies. The second study area has not been analyzed by quantitative tectonic geomorphology and the results suggest a landscape in transient state due to a continuous base-level fall produced by the formation of the Dead Sea basin.

In Vivo Brillouin Analysis of the Aging Crystalline Lens.

PubMed

Besner, Sebastien; Scarcelli, Giuliano; Pineda, Roberto; Yun, Seok-Hyun

2016-10-01

To analyze the age dependence of the longitudinal modulus of the crystalline lens in vivo using Brillouin scattering data in healthy subjects. Brillouin scans were performed along the crystalline lens in 56 eyes from 30 healthy subjects aged from 19 to 63 years. Longitudinal elastic modulus was acquired along the sagittal axis of the lens with a transverse and axial resolution of 4 and 60 μm, respectively. The relative lens stiffness was computed, and correlations with age were analyzed. Brillouin axial profiles revealed nonuniform longitudinal modulus within the lens, increasing from a softer periphery toward a stiffer central plateau at all ages. The longitudinal modulus at the central plateau showed no age dependence in a range of 19 to 45 years and a slight decrease with age from 45 to 63 years. A significant intersubject variability was observed in an age-matched analysis. Importantly, the extent of the central stiff plateau region increased steadily over age from 19 to 63 years. The slope of change in Brillouin modulus in the peripheral regions were nearly age-invariant. The adult human lens showed no measurable age-related increase in the peak longitudinal modulus. The expansion of the stiff central region of the lens is likely to be the major contributing factor to age-related lens stiffening. Brillouin microscopy may be useful in characterizing the crystalline lens for the optimization of surgical or pharmacological treatments aimed at restoring accommodative power.

Phaco-efficiency test and re-aspiration analysis of repulsed particle in phacoemulsification.

PubMed

Kim, Jae-hyung; Ko, Dong-Ah; Kim, Jae Yong; Kim, Myoung Joon; Tchah, Hungwon

2013-04-01

To measure the efficiency of phacoemulsification, we have developed a new experimental model for testing phaco-efficiency and analyzed re-aspiration of repulsed particles. Using a Kitaro wetlab system, a piece of blood agar (BA) was placed in an artificial chamber and the phacoemulsifier was placed horizontally. The settings of the phacoemulsifier (Infiniti, Alcon Laboratories) were 26 cc/min for aspiration, 350 cc/min for vacuum, and 95 cm of bottle height. The time to remove BAs was measured using Ozil 100 %, Ozil 40 %, and longitudinal 40 % of phaco power. The angle between the re-aspirated BA particles and the axis of the phacoemulsifier (re-aspiration zone, degree) was analyzed. The average time (seconds) to remove BAs was lower in the Ozil 100 % and the Ozil 40 % mode than in the longitudinal mode (0.37 ± 0.39, 0.85 ± 0.57, and 2.22 ± 1.40 respectively, P value < 0.01). Repulsion exceeding 1 mm occurred more frequently in the longitudinal mode than in the Ozil 100 % mode (100 % vs 40 %, P value = 0.01, Fisher's exact test). The average of re-aspiration zone was 25.9 ± 14.5 in the longitudinal 40 % and 54.0 ± 23.0 in the Ozil 40 % (P value = 0.016). The Ozil mode was more efficient than the longitudinal mode. In addition, the Ozil mode provided less repulsion and wider aspiration zone.

The Effects of Family Characteristics and Time Use on Teenagers' Household Labor.

ERIC Educational Resources Information Center

Gager, Constance T.; Cooney, Teresa M.; Call, Kathleen Thiede

1999-01-01

Longitudinal data collected from teenagers were analyzed for types of household chores the teens perform. The study determined that girls devoted more time to household tasks than boys, while both their efforts were greater in larger families and single-parent families. High school males spent more time on extracurricular and leisure activities,…

Intimate Partner Violence during Pregnancy and Mothers' Child Abuse Potential

ERIC Educational Resources Information Center

Casanueva, Cecilia E.; Martin, Sandra L.

2007-01-01

This research examines whether women who have experienced intimate partner violence (IPV) during pregnancy have a higher child abuse potential than women who have not experienced IPV. Data were analyzed from a longitudinal investigation of IPV during pregnancy. This study recruited 88 pregnant women during prenatal care and followed them for 1 1/2…

HIV/AIDS, Disability, and Employment. Disability Statistics Report 6.

ERIC Educational Resources Information Center

Sebesta, Douglas S.; LaPlante, Mitchell P.

This report on HIV/AIDS, disability, and employment analyzes data from the AIDS Cost and Services Utilization Survey of 1991-1992, a longitudinal study of 1,949 HIV-infected men and women. The report examines the diagnostic history of people living with HIV and its relation to function, disability, and labor force participation over time. Study…

The Parent Connection: A Necessary Link in Any Reading Program.

ERIC Educational Resources Information Center

Eder, Frances Carol

A longitudinal study observed and analyzed a group formed within a private Catholic school community on the eastern seaboard of the United States. The 25 parents within the group were from middle-class families and had children who were in grades 1 through 8. Meetings with group members were monitored, questionnaires were given to group members,…

Who Receives Speech/Language Services by 5 Years of Age in the United States?

ERIC Educational Resources Information Center

Morgan, Paul L.; Hammer, Carol Scheffner; Farkas, Geroge; Hillemeier, Marianne M.; Maczuga, Steve; Cook, Michael; Morano, Stephanie

2016-01-01

Purpose: We sought to identify factors predictive of or associated with receipt of speech/language services during early childhood. We did so by analyzing data from the Early Childhood Longitudinal Study-Birth Cohort (ECLS-B; Andreassen & Fletcher, 2005), a nationally representative dataset maintained by the U.S. Department of Education. We…

Selected Results of a Cross-Sectional/Longitudinal Research on Sex-Role Development in German Children.

ERIC Educational Resources Information Center

Trautner, Hanns Martin

Following an outline of the theoretical approach and method of a study of components of sex role development among German children, results which concern ontogenetic changes in sex role stereotypes preferences are presented. In addition, interrelations of different components of sex role development and cognitive variables are analyzed. The…

Selling College: A Longitudinal Study of American College Football Bowl Game Public Service Announcements

ERIC Educational Resources Information Center

Tobolowsky, Barbara F.; Lowery, John Wesley

2014-01-01

Using ideological analysis as a frame, researchers analyzed institutionally created commercials (PSAs) that appeared in 28 U.S. college football bowl games over a seven-year period (2003-2009) to better understand the universities' brands as represented in these advertisements. They found many common elements such as showing traditional…

Examining Mobile Learning Trends 2003-2008: A Categorical Meta-Trend Analysis Using Text Mining Techniques

ERIC Educational Resources Information Center

Hung, Jui-Long; Zhang, Ke

2012-01-01

This study investigated the longitudinal trends of academic articles in Mobile Learning (ML) using text mining techniques. One hundred and nineteen (119) refereed journal articles and proceedings papers from the SCI/SSCI database were retrieved and analyzed. The taxonomies of ML publications were grouped into twelve clusters (topics) and four…

Subjective Discipline and the Social Control of Black Girls in Pipeline Schools

ERIC Educational Resources Information Center

Martin, Jennifer; Smith, Julia

2017-01-01

Using an intersectional feminist critical race lens, we utilized the Education Longitudinal Study (2002) data comparing tenth grade African American girls to White girls, analyzing whether the student was ever held back, teacher reports of problem behaviors in classrooms, and whether the student did not graduate from high school in the four years…

Influences and Mediators of the Effect of Poverty on Young Adolescent Depressive Symptoms.

ERIC Educational Resources Information Center

Eamon, Mary Keegan

2002-01-01

Analyzed data from the mother-child data set of the National Longitudinal Survey of Youth for 898 young adolescents (10-12 years) to study the influences that explain the relations between poverty and depressive symptoms measured 2 years later. Findings show that youth depressive symptoms are multiply determined, and that poverty can adversely…

Maternal Labor Supply and Children's Cognitive Development. NBER Working Paper Series.

ERIC Educational Resources Information Center

Blau, Francine D.; Grossberg, Adam J.

This study used a sample of 3- and 4-year-old children of female respondents from the 1986 National Longitudinal Surveys Youth Cohort to analyze the relationship between maternal labor supply and children's cognitive development. Respondents were 21 to 29 years old in 1986. Thus, the sample consisted of children of relatively young mothers.…

Development of Pointing Gestures in Children with Typical and Delayed Language Acquisition

ERIC Educational Resources Information Center

Lüke, Carina; Ritterfeld, Ute; Grimminger, Angela; Liszkowski, Ulf; Rohlfing, Katharina J.

2017-01-01

Purpose: This longitudinal study compared the development of hand and index-finger pointing in children with typical language development (TD) and children with language delay (LD). First, we examined whether the number and the form of pointing gestures during the second year of life are potential indicators of later LD. Second, we analyzed the…

A Longitudinal Developmental Analysis of Students' Causality Beliefs about School Performance

ERIC Educational Resources Information Center

Roque, Isabel; de Lemos, Marina Serra; Gonçalves, Teresa

2014-01-01

This study examined the development of school-related causality beliefs which are children's generalized perceptions of the utility or power of different categories of specific means in producing school outcomes. Based on the action theory perspective, we analyzed the developmental model of these beliefs as well as the trajectories of the…

Changes in Student Attributions Due to the Implementation of Central Exit Exams

ERIC Educational Resources Information Center

Oerke, Britta; Maag Merki, Katharina; Holmeier, Monika; Jager, Daniela J.

2011-01-01

The central aim of standardized exit exams is to motivate students and teachers to work harder on critical subject matters and thus increase student achievement. However, the effects of the implementation of central exams on student motivation have not been analyzed in a longitudinal section until now. In the present study, the consequences of…

School Social Capital and Body Mass Index in the National Longitudinal Study of Adolescent Health

ERIC Educational Resources Information Center

Richmond, Tracy K.; Milliren, Carly; Walls, Courtney E.; Kawachi, Ichiro

2014-01-01

Background: Social capital in neighborhoods and workplaces positively affects health. Less is known about the influence of school social capital on student health outcomes, in particular weight status. We sought to examine the association between individual- and school-level social capital and student body mass index (BMI). Methods: Analyzing data…

Effects of School Mobility on Adolescent Social Ties and Academic Adjustment

ERIC Educational Resources Information Center

Langenkamp, Amy G.

2016-01-01

Why are transfer students at an increased risk for disengagement and dropout? Previous research suggests that the loss of school-based social relationships play a role. Data from the National Longitudinal Study of Adolescent Health (Add Health) are used to analyze what predicts student transfer and what effect this has on students' social…

Acculturation Stress, Drinking, and Intimate Partner Violence among Hispanic Couples in the U.S

ERIC Educational Resources Information Center

Caetano, Raul; Ramisetty-Mikler, Suhasini; Caetano Vaeth, Patrice A.; Harris, T. Robert

2007-01-01

This article examines the cross-sectional association between acculturation, acculturation stress, drinking, and intimate partner violence (IPV) among Hispanic couples in the U.S. The data being analyzed come from a multi-cluster random household sample of couples interviewed as part of the second wave of a 5-year national longitudinal study. The…

Child Custody Loss among Women with Persistent Severe Mental Illness

ERIC Educational Resources Information Center

Hollingsworth, Leslie Doty

2004-01-01

The author analyzed quantitative data from an NIMH-funded longitudinal study of 322 women with persistent severe mental illness (SMI) and qualitative data from semistructured interviews with 82 of the women who ever lost custody of a child. The purpose was to test the hypothesis, derived from human ecology theory, that individual and environmental…

Effects of individual, community and landscape drivers on the dynamics of a wildland forest epidemic

Treesearch

Sarah E. Haas; J. Hall Cushman; Whalen W. Dillon; Nathan E. Rank; David M. Rizzo; Ross K. Meentemeyer

2016-01-01

The challenges posed by observing host-pathogen-environment interactions across large geographic extents and over meaningful time scales limit our ability to understand and manage wildland epidemics. We conducted a landscape-scale, longitudinal study designed to analyze the dynamics of sudden oak death (an emerging forest disease caused by Phytophthora...

Analysis of Speech Disorders in Acute Pseudobulbar Palsy: a Longitudinal Study of a Patient with Lingual Paralysis.

ERIC Educational Resources Information Center

Leroy-Malherbe, V.; Chevrie-Muller, C.; Rigoard, M. T.; Arabia, C.

1998-01-01

This case report describes the case of a 52-year-old man with bilateral central lingual paralysis following a myocardial infarction. Analysis of speech recordings 15 days and 18 months after the attack were acoustically analyzed. The case demonstrates the usefulness of acoustic analysis to detect slight acoustic differences. (DB)

The Roles of Victim and Offender Substance Use in Sexual Assault Outcomes

ERIC Educational Resources Information Center

Brecklin, Leanne R.; Ullman, Sarah E.

2010-01-01

The impact of victim and offender preassault substance use on the outcomes of sexual assault incidents was analyzed. Nine hundred and seventy female sexual assault victims were identified from the first wave of a longitudinal study based on a convenience sampling strategy. Multivariate models showed that victim injury was more likely in assaults…

A Short Story Approach to Analyzing Teacher (Imagined) Identities over Time

ERIC Educational Resources Information Center

Barkhuizen, Gary

2016-01-01

In this article the researcher reports on a longitudinal study which investigated the imagined identities of a preservice English teacher in New Zealand and compared these with the identities she negotiated in her teacher education and then teaching practice nearly nine years later. The teacher, an immigrant from the Pacific Island of Tonga,…

Do Gender and Ethnicity Affect Civic Engagement and Academic Progress? Working Paper 53

ERIC Educational Resources Information Center

Davila, Alberto; Mora, Marie T.

2007-01-01

Using panel data from the National Education Longitudinal Study of 1988 (NELS), the authors first analyze how civic engagement (measured in terms of community service and participation in student government) undertaken at the high school level varies across race/ethnicity and gender. The findings indicate that female high school students tend to…

School Sector and Student Achievement in the Era of Standards Based Reforms

ERIC Educational Resources Information Center

Carbonaro, William; Covay, Elizabeth

2010-01-01

The authors examine whether standards based accountability reforms of the past two decades have closed the achievement gap among public and private high school students. They analyzed data from the Education Longitudinal Study (ELS) to examine sector differences in high school achievement in the era of standards based reforms. The authors found…

Exposure to Community Violence and Adolescents' Internalizing Behaviors among African American and Asian American Adolescents

ERIC Educational Resources Information Center

Chen, Wan-Yi

2010-01-01

Exposure to community violence can seriously threaten healthy adolescent development. This longitudinal study examines the relationship between exposure to violence in the community and the internalizing behaviors of Asian American and African American adolescents. Data analyzed was from 901 adolescents (57.9% female and 42.1% male, and 84.7%…

Estimating True Short-Term Consistency in Vocational Interests: A Longitudinal SEM Approach

ERIC Educational Resources Information Center

Gaudron, Jean-Philippe; Vautier, Stephane

2007-01-01

This study aimed at estimating the correlation between true scores (true consistency) of vocational interest over a short time span in a sample of 1089 adults. Participants were administered 54 items assessing vocational, family, and leisure interests twice over a 1-month period. Responses were analyzed with a multitrait (MT) model, which supposes…

Test Scores, Dropout Rates, and Transfer Rates as Alternative Indicators of High School Performance

ERIC Educational Resources Information Center

Rumberger, Russell W.; Palardy, Gregory J.

2005-01-01

This study investigated the relationships among several different indicators of high school performance: test scores, dropout rates, transfer rates, and attrition rates. Hierarchical linear models were used to analyze panel data from a sample of 14,199 students who took part in the National Education Longitudinal Survey of 1988. The results…

General Education Development (GED) Recipients' Life Course Experiences: Humanizing the Findings

ERIC Educational Resources Information Center

Hartigan, Lacey A.

2017-01-01

This study examines a range of GED recipients' life course contexts and experiences and their relationship with long-term outcomes. Using descriptive comparisons, bivariate tests, and propensity-score matched regression models to analyze data from rounds 1-15 of the National Longitudinal Survey of Youth, 1997, analyses aim to examine: (1)…

The Impact of Historically Black Colleges and Universities on the Academic Success of African-American Students

ERIC Educational Resources Information Center

Kim, Mikyong Minsun; Conrad, Clifton F.

2006-01-01

Anchored in national longitudinal data analyzed through hierarchical linear and non-linear modeling, this study found that African-American students have a similar probability of obtaining a BA degree whether they attended a historically Black college or university (HBCU) or a historically White college or university (HWCU). Among…

The Impact of Campus Context, College Encounters, and Religious/Spiritual Struggle on Ecumenical Worldview Development

ERIC Educational Resources Information Center

Bryant, Alyssa N.

2011-01-01

Using a national longitudinal sample of 14,274 college students generated as part of the UCLA Spirituality in Higher Education Project, this study employed structural equation modeling to analyze how students develop an ecumenical worldview. The findings suggest that challenging co-curricular experiences and the salience of religion and…

Homework Works If Homework Quality Is High: Using Multilevel Modeling to Predict the Development of Achievement in Mathematics

ERIC Educational Resources Information Center

Dettmers, Swantje; Trautwein, Ulrich; Ludtke, Oliver; Kunter, Mareike; Baumert, Jurgen

2010-01-01

The present study examined the associations of 2 indicators of homework quality (homework selection and homework challenge) with homework motivation, homework behavior, and mathematics achievement. Multilevel modeling was used to analyze longitudinal data from a representative national sample of 3,483 students in Grades 9 and 10; homework effects…

How the Instructional and Learning Environments of Liberal Arts Colleges Enhance Cognitive Development

ERIC Educational Resources Information Center

Pascarella, Ernest T.; Wang, Jui-Sheng; Trolian, Teniell L.; Blaich, Charles

2013-01-01

This study analyzes longitudinal data from 17 four-year institutions in the United States to determine how the distinctive instructional and learning environment of American liberal arts colleges accounts for the positive impact of liberal arts college attendance on four-year growth in critical thinking skills and need for cognition. We find that,…

The Acquisition of Relative Clauses in Spontaneous Child Speech in Mandarin Chinese

ERIC Educational Resources Information Center

Chen, Jidong; Shirai, Yasuhiro

2015-01-01

This study investigates the developmental trajectory of relative clauses (RCs) in Mandarin-learning children's speech. We analyze the spontaneous production of RCs by four monolingual Mandarin-learning children (0;11 to 3;5) and their input from a longitudinal naturalistic speech corpus (Min, 1994). The results reveal that in terms of the…

Generalization of experimental data on heat transfer in permeable shells made of porous reticular materials

NASA Astrophysics Data System (ADS)

Polyakov, A. F.; Strat'ev, V. K.; Tret'yakov, A. F.; Shekhter, Yu. L.

2010-06-01

Heat transfer from six samples of porous reticular material to cooling gas (air) at small Reynolds numbers is experimentally studied. The specific features pertinent to heat transfer essentially affected by longitudinal heat conductivity along gas flow are analyzed. The experimental results are generalized in the form of dimensionless empirical relations.

Estimating inverse-probability weights for longitudinal data with dropout or truncation: The xtrccipw command.

PubMed

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.

Longitudinal variations of brain functional connectivity: A case report study based on a mouse model of epilepsy.

PubMed

Erramuzpe, A; Encinas, J M; Sierra, A; Maletic-Savatic, M; Brewster, A L; Anderson, Anne E; Stramaglia, S; Cortes, Jesus M

2015-01-01

Brain Functional Connectivity (FC) quantifies statistical dependencies between areas of the brain. FC has been widely used to address altered function of brain circuits in control conditions compared to different pathological states, including epilepsy, a major neurological disorder. However, FC also has the as yet unexplored potential to help us understand the pathological transformation of the brain circuitry. Our hypothesis is that FC can differentiate global brain interactions across a time-scale of days. To this end, we present a case report study based on a mouse model for epilepsy and analyze longitudinal intracranial electroencephalography data of epilepsy to calculate FC changes from the initial insult (status epilepticus) and over the latent period, when epileptogenic networks emerge, and at chronic epilepsy, when unprovoked seizures occur as spontaneous events. We found that the overall network FC at low frequency bands decreased immediately after status epilepticus was provoked, and increased monotonously later on during the latent period. Overall, our results demonstrate the capacity of FC to address longitudinal variations of brain connectivity across the establishment of pathological states.

Clinical and Radiographic Characteristics as Predictive Factors of Swelling and Trismus after Mandibular Third Molar Surgery: A Longitudinal Approach

PubMed Central

Pérez-González, José Manuel; Esparza-Villalpando, Vicente; Martínez-Rider, Ricardo; Noyola-Frías, Miguel Ángel

2018-01-01

Introduction Factors that contribute to swelling and trismus are complex, and they are originated by surgical trauma. The aim of the present study was to determine whether clinical and radiographic factors could predict the level of swelling and trismus after lower third molar surgery, through longitudinal approach. Methodology A prospective longitudinal trial was carried out. Forty-five patients of both genders with clinical and radiographic diagnosis of asymptomatic mandibular impacted third molar and with no intake of analgesic or anti-inflammatory drugs 12 h prior to surgery were recruited and evaluated in a 72 h follow-up period. A mixed repeated measures model and backward and restricted maximal likelihood methods were used to analyze the data. Results Male gender, body mass index (BMI), the relation to the lingual and buccal walls, and age were determinants for predicting postoperative swelling and for exerting a significant influence (P < 0.05). Conclusions This study suggests the association of male gender, the relation to lingual and buccal walls, BMI, and age with measurement of swelling. PMID:29849848

An analytical study and wind tunnel tests of an aeromechanical gust-alleviation system for a light airplane

NASA Technical Reports Server (NTRS)

Stewart, E. C.

1976-01-01

The results of an analytical study of a system using stability derivatives determined in static wind tunnel tests of a 1/6 scale model of a popular, high wing, light airplane equipped with the gust alleviation system are reported. The longitudinal short period mode dynamics of the system are analyzed, and include the following: (1) root loci, (2) airplane frequency responses to vertical gusts, (3) power spectra of the airplane responses in a gust spectrum, (4) time history responses to vertical gusts, and (5) handling characteristics. The system reduces the airplane's normal acceleration response to vertical gusts while simultaneously increasing the pitching response and reducing the damping of the longitudinal short period mode. The normal acceleration response can be minimized by using the proper amount of static alleviation and a fast response system with a moderate amount of damping. The addition of a flap elevator interconnect or a pitch damper system further increases the alleviation while moderating the simultaneous increase in pitching response. The system provides direct lift control and may reduce the stick fixed longitudinal static stability.

Estimating inverse-probability weights for longitudinal data with dropout or truncation: The xtrccipw command

PubMed Central

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

Applications of Multidimensional Item Response Theory Models with Covariates to Longitudinal Test Data. Research Report. ETS RR-16-21

ERIC Educational Resources Information Center

Fu, Jianbin

2016-01-01

The multidimensional item response theory (MIRT) models with covariates proposed by Haberman and implemented in the "mirt" program provide a flexible way to analyze data based on item response theory. In this report, we discuss applications of the MIRT models with covariates to longitudinal test data to measure skill differences at the…

Analysis of wood cantilever loaded at free end

Treesearch

Jen Y. Liu; Douglas R. Rammer

2003-01-01

A wood cantilever loaded at the free end was analyzed using the anisotropic elasticity theory. This report presents a two-dimensional numerical example of a Sitka spruce cantilever in the longitudinal-radial plane. When the grain slope is zero, ie., the beam axis coincides with the longitudinal axis of wood, the stresses in the beam and the deflection of the beam are...

Estimation of longitudinal force, lateral vehicle speed and yaw rate for four-wheel independent driven electric vehicles

NASA Astrophysics Data System (ADS)

Chen, Te; Xu, Xing; Chen, Long; Jiang, Haobing; Cai, Yingfeng; Li, Yong

2018-02-01

Accurate estimation of longitudinal force, lateral vehicle speed and yaw rate is of great significance to torque allocation and stability control for four-wheel independent driven electric vehicle (4WID-EVs). A fusion method is proposed to estimate the longitudinal force, lateral vehicle speed and yaw rate for 4WID-EVs. The electric driving wheel model (EDWM) is introduced into the longitudinal force estimation, the longitudinal force observer (LFO) is designed firstly based on the adaptive high-order sliding mode observer (HSMO), and the convergence of LFO is analyzed and proved. Based on the estimated longitudinal force, an estimation strategy is then presented in which the strong tracking filter (STF) is used to estimate lateral vehicle speed and yaw rate simultaneously. Finally, co-simulation via Carsim and Matlab/Simulink is carried out to demonstrate the effectiveness of the proposed method. The performance of LFO in practice is verified by the experiment on chassis dynamometer bench.

Methods for Analyzing the Attainment of Graduate School Milestones: A Case Study. GRE Board Professional Report No. 86-3P.

ERIC Educational Resources Information Center

Zwick, Rebecca; Braun, Henry I.

Using a data base compiled by the Graduate School of Northwestern University, a longitudinal study of the graduate school careers of 2,211 students in 14 programs was conducted. Among the most prominent findings was the increase in the enrollment of foreign students. The patterns of attainment of graduate school milestones, such as Ph. D.…

How Black Boys with Disabilities End up in Honors Classes while Others without Disabilities End up in Special Education

ERIC Educational Resources Information Center

Toldson, Ivory A.

2011-01-01

For the data presented in this report, the author analyzed 17,587 Black, Hispanic, and White male and female students (Black males; N = 1,149) who completed the High School Longitudinal Study of 2009 (Ingels et al., 2011). This is a brief report from a larger study completed under the auspices of the National Dropout Prevention Center for Students…

STATISTICAL GROWTH MODELING OF LONGITUDINAL DT-MRI FOR REGIONAL CHARACTERIZATION OF EARLY BRAIN DEVELOPMENT.

PubMed

Sadeghi, Neda; Prastawa, Marcel; Fletcher, P Thomas; Gilmore, John H; Lin, Weili; Gerig, Guido

2012-01-01

A population growth model that represents the growth trajectories of individual subjects is critical to study and understand neurodevelopment. This paper presents a framework for jointly estimating and modeling individual and population growth trajectories, and determining significant regional differences in growth pattern characteristics applied to longitudinal neuroimaging data. We use non-linear mixed effect modeling where temporal change is modeled by the Gompertz function. The Gompertz function uses intuitive parameters related to delay, rate of change, and expected asymptotic value; all descriptive measures which can answer clinical questions related to growth. Our proposed framework combines nonlinear modeling of individual trajectories, population analysis, and testing for regional differences. We apply this framework to the study of early maturation in white matter regions as measured with diffusion tensor imaging (DTI). Regional differences between anatomical regions of interest that are known to mature differently are analyzed and quantified. Experiments with image data from a large ongoing clinical study show that our framework provides descriptive, quantitative information on growth trajectories that can be directly interpreted by clinicians. To our knowledge, this is the first longitudinal analysis of growth functions to explain the trajectory of early brain maturation as it is represented in DTI.

General self-efficacy and posttraumatic stress after a natural disaster: a longitudinal study.

PubMed

Nygaard, Egil; Hussain, Ajmal; Siqveland, Johan; Heir, Trond

2016-04-06

Self-efficacy may be an important factor in individuals' recovery from posttraumatic stress reactions after a natural disaster. However, few longitudinal studies have investigated whether self-efficacy predicts the course of posttraumatic recovery beyond lower initial levels of distress. The purpose of the present study was to investigate whether general self-efficacy is related to recovery from posttraumatic stress reactions from a longitudinal perspective. A total of 617 Norwegians exposed to the 2004 Southeast Asian tsunami completed self-report questionnaires measuring their level of disaster exposure and general self-efficacy at 6 months and posttraumatic stress reactions 6 months and 2 years post-disaster. Predictors of changes in posttraumatic stress reactions were analyzed with multivariate mixed effects models. Self-efficacy at 6 months post-disaster was unrelated to trauma exposure and inversely related to posttraumatic stress reactions at 6 months and 2 years post-disaster. However, self-efficacy was not related to recovery from posttraumatic stress reactions between 6 months and 2 years post-disaster. In conclusion, general self-efficacy is related to lower levels of posttraumatic stress reactions in the first months after a disaster but does not appear to be related to improved recovery rates over the longer term.

Bayesian inference for two-part mixed-effects model using skew distributions, with application to longitudinal semicontinuous alcohol data.

PubMed

Xing, Dongyuan; Huang, Yangxin; Chen, Henian; Zhu, Yiliang; Dagne, Getachew A; Baldwin, Julie

2017-08-01

Semicontinuous data featured with an excessive proportion of zeros and right-skewed continuous positive values arise frequently in practice. One example would be the substance abuse/dependence symptoms data for which a substantial proportion of subjects investigated may report zero. Two-part mixed-effects models have been developed to analyze repeated measures of semicontinuous data from longitudinal studies. In this paper, we propose a flexible two-part mixed-effects model with skew distributions for correlated semicontinuous alcohol data under the framework of a Bayesian approach. The proposed model specification consists of two mixed-effects models linked by the correlated random effects: (i) a model on the occurrence of positive values using a generalized logistic mixed-effects model (Part I); and (ii) a model on the intensity of positive values using a linear mixed-effects model where the model errors follow skew distributions including skew- t and skew-normal distributions (Part II). The proposed method is illustrated with an alcohol abuse/dependence symptoms data from a longitudinal observational study, and the analytic results are reported by comparing potential models under different random-effects structures. Simulation studies are conducted to assess the performance of the proposed models and method.

Longitudinal development of cortical thickness, folding, and fiber density networks in the first 2 years of life.

PubMed

Nie, Jingxin; Li, Gang; Wang, Li; Shi, Feng; Lin, Weili; Gilmore, John H; Shen, Dinggang

2014-08-01

Quantitatively characterizing the development of cortical anatomical networks during the early stage of life plays an important role in revealing the relationship between cortical structural connection and high-level functional development. The development of correlation networks of cortical-thickness, cortical folding, and fiber-density is systematically analyzed in this article to study the relationship between different anatomical properties during the first 2 years of life. Specifically, longitudinal MR images of 73 healthy subjects from birth to 2 year old are used. For each subject at each time point, its measures of cortical thickness, cortical folding, and fiber density are projected to its cortical surface that has been partitioned into 78 cortical regions. Then, the correlation matrices for cortical thickness, cortical folding, and fiber density at each time point can be constructed, respectively, by computing the inter-regional Pearson correlation coefficient (of any pair of ROIs) across all 73 subjects. Finally, the presence/absence pattern (i.e., binary pattern) of the connection network is constructed from each inter-regional correlation matrix, and its statistical and anatomical properties are adopted to analyze the longitudinal development of anatomical networks. The results show that the development of anatomical network could be characterized differently by using different anatomical properties (i.e., using cortical thickness, cortical folding, or fiber density). Copyright © 2013 Wiley Periodicals, Inc.

Ultimate Longitudinal Strength of Composite Ship Hulls

NASA Astrophysics Data System (ADS)

Zhang, Xiangming; Huang, Lingkai; Zhu, Libao; Tang, Yuhang; Wang, Anwen

2017-01-01

A simple analytical model to estimate the longitudinal strength of ship hulls in composite materials under buckling, material failure and ultimate collapse is presented in this paper. Ship hulls are regarded as assemblies of stiffened panels which idealized as group of plate-stiffener combinations. Ultimate strain of the plate-stiffener combination is predicted under buckling or material failure with composite beam-column theory. The effects of initial imperfection of ship hull and eccentricity of load are included. Corresponding longitudinal strengths of ship hull are derived in a straightforward method. A longitudinally framed ship hull made of symmetrically stacked unidirectional plies under sagging is analyzed. The results indicate that present analytical results have a good agreement with FEM method. The initial deflection of ship hull and eccentricity of load can dramatically reduce the bending capacity of ship hull. The proposed formulations provide a simple but useful tool for the longitudinal strength estimation in practical design.

Sex, violence, & rock n' roll: Longitudinal effects of music on aggression, sex, and prosocial behavior during adolescence.

PubMed

Coyne, Sarah M; Padilla-Walker, Laura M

2015-06-01

The current study examined longitudinal associations between listening to aggression, sex, and prosocial behavior in music on a number of behavioral outcomes across a one-year period during adolescence. Adolescents (N = 548, M age = 15.32, 52% female) completed a number of questionnaires on musical preferences, general media use, aggression, sexual outcomes, and prosocial behavior at two different time points separated by about one year. Using structural equation modeling to analyze the data, results revealed that listening to aggression in music was associated with increased aggression and decreased prosocial behavior over time, even when controlling for initial levels of these behaviors. Listening to sexual content in music was associated with earlier initiation of sexual intercourse and a trend for a higher number of sexual partners (reported at Time 2). Prosocial behavior in music was not associated with any behavioral outcome longitudinally. Collectively, these results suggest that listening to certain types of content in music can have a longitudinal effect on behavior during adolescence. Copyright © 2015 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

Stiffness and Poisson ratio in longitudinal compression of fiber yarns in meso-FE modelling of composite reinforcement forming

NASA Astrophysics Data System (ADS)

Wang, D.; Naouar, N.; Vidal-Salle, E.; Boisse, P.

2018-05-01

In meso-scale finite element modeling, the yarns of the reinforcement are considered to be solids made of a continuous material in contact with their neighbors. The present paper consider the mechanical behavior of these yarns that can happen for some loadings of the reinforcement. The yarns present a specific mechanical behavior when under longitudinal compression because they are made up of a large number of fibers, Local buckling of the fibers causes the compressive stiffness of the continuous material representing the yarn to be much weaker than when under tension. In addition, longitudinal compression causes an important transverse expansion. It is shown that the transverse expansion can be depicted by a Poisson ratio that remained roughly constant when the yarn length and the compression strain varied. Buckling of the fibers significantly increases the transverse dimensions of the yarn which leads to a large Poisson ratio (up to 12 for a yarn analyzed in the present study). Meso-scale finite element simulations of reinforcements with binder yarns submitted to longitudinal compression showed that these improvements led to results in good agreement with micro-CT analyses.

Longitudinal vibration and stability analysis of carbon nanotubes conveying viscous fluid

NASA Astrophysics Data System (ADS)

Oveissi, Soheil; Toghraie, Davood; Eftekhari, Seyyed Ali

2016-09-01

Nowadays, carbon nanotubes (CNT) play an important role in practical applications in fluidic devices. To this end, researchers have studied various aspects of vibration analysis of a behavior of CNT conveying fluid. In this paper, based on nonlocal elasticity theory, single-walled carbon nanotube (SWCNT) is simulated. To investigate and analyze the effect of internal fluid flow on the longitudinal vibration and stability of SWCNT, the equation of motion for longitudinal vibration is obtained by using Navier-Stokes equations. In the governing equation of motion, the interaction of fluid-structure, dynamic and fluid flow velocity along the axial coordinate of the nanotube and the nano-scale effect of the structure are considered. To solve the nonlocal longitudinal vibration equation, the approximate Galerkin method is employed and appropriate simply supported boundary conditions are applied. The results show that the axial vibrations of the nanotubesstrongly depend on the small-size effect. In addition, the fluid flowing in nanotube causes a decrease in the natural frequency of the system. It is obvious that the system natural frequencies reach zero at lower critical flow velocities as the wave number increases. Moreover, the critical flow velocity decreases as the nonlocal parameter increases.

Utilizing wheel-ring architecture for stable and selectable single-longitudinal-mode erbium fiber laser

NASA Astrophysics Data System (ADS)

Yeh, Chien-Hung; Yang, Zi-Qing; Huang, Tzu-Jung; Chow, Chi-Wai

2018-03-01

To achieve a steady single-longitudinal-mode (SLM) erbium-doped fiber (EDF) laser, the wheel-ring architecture is proposed in the laser cavity. According to Vernier effect, the proposed wheel-ring can produce three different free spectrum ranges (FSRs) to serve as the mode-filter for suppressing the densely multi-longitudinal-mode (MLM). Here, to complete wavelength-tunable EDF laser, an optical tunable bandpass filter (OTBF) is utilized inside the cavity for tuning arbitrarily. In addition, the entire output performances of the proposed EDF wheel-ring laser are also discussed and analyzed experimentally.

Longitudinal Analysis of Superficial Midfacial Fat Volumes Over a 10-Year Period.

PubMed

Tower, Jacob; Seifert, Kimberly; Paskhover, Boris

2018-04-11

Volumetric changes to facial fat that occur with aging remain poorly understood. The aim of this study was to evaluate for longitudinal changes to midfacial fat volumes in a group of individuals. We conducted a retrospective longitudinal study of adult subjects who underwent multiple facial computed tomographic (CT) scans timed at least 8 years apart. Subjects who underwent facial surgery or suffered facial trauma were excluded. Facial CT scans were analyzed, and superficial cheek fat volumes were measured and compared to track changes that occurred with aging. Fourteen subjects were included in our analysis of facial aging (5 male, 9 female; mean initial age 50.9 years; mean final age 60.4 years). In the right superficial cheek there was an increase in mean (SD) superficial fat volume from 10.33 (2.01) to 10.50 (1.80) cc, which was not statistically significant (P = 0.75). Similar results were observed in the left cheek. There were no statistically significant longitudinal changes to caudal, middle, or cephalad subdivisions of bilateral superficial cheek fat. A simple linear regression was performed to predict superficial cheek fat pad volume based on age which did not reach statistical significance (P = 0.31), with an R 2 of 0.039. This study is the first to quantitatively assess for longitudinal changes to midfacial fat in a group of individuals. Superficial cheek fat remained stable as subjects aged from approximately 50 to 60 years old, with no change in total volume or redistribution within a radiographically defined compartment. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Association of baseline sex hormone levels with baseline and longitudinal changes in waist-to-hip ratio: Multi-Ethnic Study of Atherosclerosis.

PubMed

Vaidya, D; Dobs, A; Gapstur, S M; Golden, S H; Cushman, M; Liu, K; Ouyang, P

2012-12-01

Waist-to-hip ratio (WHR) is strongly associated with prevalent atherosclerosis. We analyzed the associations of baseline serum levels of testosterone (T), estradiol (E2), sex-hormone-binding globulin (SHBG) and dehydroepiandrosterone (DHEA) with WHR in the Multi-Ethnic Study of Atherosclerosis (MESA) cohort. Baseline data was available for 3144 men and 2038 postmenopausal women, who were non-users of hormone therapy, who were 45-84 years of age, and of White, Chinese, Black or Hispanic racial/ethnic groups. Of these, 2708 men and 1678 women also had longitudinal measurements of WHR measured at the second and/or the third study visits (median follow-up 578 days and 1135 days, respectively). In cross-sectional analyses adjusted for age, race and cardiovascular disease risk factors, T was negatively associated with baseline WHR in men, whereas in both sexes, E2 was positively associated and SHBG was negatively associated with WHR (all P<0.001). In longitudinal analyses, further adjusted for follow-up time and baseline WHR, baseline T was negatively associated with WHR at follow-up (P=0.001) in men, whereas in both sexes, E2 was positively associated (P=0.004) and SHBG was negatively associated with WHR (P<0.001). The longitudinal association of E2, but not T, was independent of SHBG. In cross-sectional or longitudinal analyses, there were no associations between DHEA and WHR in either men or women. Sex hormones are associated with WHR at baseline and also during follow-up above and beyond their baseline association. Future research is needed to determine if manipulation of hormones is associated with changes in central obesity.

Age- and Sex-Related Influences on Left Ventricular Mechanics in Elderly Individuals Free of Prevalent Heart Failure: The ARIC Study (Atherosclerosis Risk in Communities).

PubMed

Hung, Chung-Lieh; Gonçalves, Alexandra; Shah, Amil M; Cheng, Susan; Kitzman, Dalane; Solomon, Scott D

2017-01-01

Advanced age is related to left ventricular (LV) remodeling. We sought to investigate the relationships between aging, elevated hemodynamic load, cardiac mechanics, and LV remodeling in an elderly community-based population. We studied 1105 subjects (76±5 years, 61% women) without prevalent heart failure, who attended the visit 5 of the ARIC study (Atherosclerosis Risk in Communities). LV global longitudinal strain, global circumferential strain, and torsion indices were analyzed using 3-dimensional echocardiography. Advanced age was associated with greater LV concentricity, lower myocardial diastolic relaxation, reduced global longitudinal strain (adjusted estimate, 0.39±0.19% (SE)/decade; P=0.038), borderline greater global circumferential strain (adjusted estimate, -0.59±0.36% (SE)/decade; P=0.08), and higher torsion indices (adjusted estimate for torsion, 0.33±0.04° (SE)/decade; P<0.001). In addition, greater concentricity was associated with decreased global longitudinal strain and greater torsion in multivariable models (all P<0.001). Women showed smaller LV cavity size, greater concentricity, lower myocardial relaxation velocity E', though demonstrated greater global longitudinal strain, global circumferential strain, and torsion than men (all P<0.05). Overall, subjects with hypertension and increasing age were more likely to have higher torsion, though the association between advanced age and greater torsion was more pronounced in women than in men (both interaction P<0.05). In an asymptomatic, senescent community-dwelling population, we observed a distinct, sex-specific pattern of cardiac remodeling. Although we observed worse diastolic and longitudinal function with advanced age or elevated load in both sexes, a significant increase of torsion was more pronounced in women. © 2017 American Heart Association, Inc.

The comorbidity of anxiety and depressive symptoms in older adults with attention-deficit/hyperactivity disorder: a longitudinal study.

PubMed

Michielsen, Marieke; Comijs, Hannie C; Semeijn, Evert J; Beekman, Aartjan T F; Deeg, Dorly J H; Sandra Kooij, J J

2013-06-01

Comorbidity between Attention-Deficit/Hyperactivity Disorder (ADHD) and depression and anxiety disorders in children and young to middle-aged adults has been well documented in the literature. Yet, it is still unknown whether this comorbidity persists into later life. The aim of this study is therefore to examine the comorbidity of anxiety and depressive symptoms among older adults with ADHD. This is examined both using cross-sectional and longitudinal data. Data were used from the Longitudinal Aging Study Amsterdam (LASA). Participants were examined in three measurement cycles, covering six years. They were asked about depressive and anxiety symptoms. To diagnose ADHD, the DIVA 2.0, a diagnostic interview was administered among a subsample (N=231, age 60-94). In addition to the ADHD diagnosis, the association between the sum score of ADHD symptoms and anxiety and depressive symptoms was examined. Data were analyzed by means of linear regression analyses and linear mixed models. Both ADHD diagnosis and more ADHD symptoms were associated with more anxiety and depressive symptoms cross-sectionally as well as longitudinally. The longitudinal analyses showed that respondents with higher scores of ADHD symptoms reported an increase of depressive symptoms over six years whereas respondents with fewer ADHD symptoms remained stable. The ADHD diagnosis is based on the DSM-IVcriteria, which were developed for children, and have not yet been validated in (older) adults. It appears that the association between ADHD and anxiety/depression remains in place with aging. This suggests that, in clinical practice, directing attention to both in concert may be fruitful. Copyright © 2012 Elsevier B.V. All rights reserved.

Longitudinal Receptive American Sign Language Skills Across a Diverse Deaf Student Body.

PubMed

Beal-Alvarez, Jennifer S

2016-04-01

This article presents results of a longitudinal study of receptive American Sign Language (ASL) skills for a large portion of the student body at a residential school for the deaf across four consecutive years. Scores were analyzed by age, gender, parental hearing status, years attending the residential school, and presence of a disability (i.e., deaf with a disability). Years 1 through 4 included the ASL Receptive Skills Test (ASL-RST); Years 2 through 4 also included the Receptive Test of ASL (RT-ASL). Student performance for both measures positively correlated with age; deaf students with deaf parents scored higher than their same-age peers with hearing parents in some instances but not others; and those with a documented disability tended to score lower than their peers without disabilities. These results provide longitudinal findings across a diverse segment of the deaf/hard of hearing residential school population. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Estimating and Identifying Unspecified Correlation Structure for Longitudinal Data

PubMed Central

Hu, Jianhua; Wang, Peng; Qu, Annie

2014-01-01

Identifying correlation structure is important to achieving estimation efficiency in analyzing longitudinal data, and is also crucial for drawing valid statistical inference for large size clustered data. In this paper, we propose a nonparametric method to estimate the correlation structure, which is applicable for discrete longitudinal data. We utilize eigenvector-based basis matrices to approximate the inverse of the empirical correlation matrix and determine the number of basis matrices via model selection. A penalized objective function based on the difference between the empirical and model approximation of the correlation matrices is adopted to select an informative structure for the correlation matrix. The eigenvector representation of the correlation estimation is capable of reducing the risk of model misspecification, and also provides useful information on the specific within-cluster correlation pattern of the data. We show that the proposed method possesses the oracle property and selects the true correlation structure consistently. The proposed method is illustrated through simulations and two data examples on air pollution and sonar signal studies. PMID:26361433

Characterization of azimuthal and longitudinal modes in rolled-up InGaAs/GaAs microtubes at telecom wavelengths.

PubMed

Zhong, Qiuhang; Tian, Zhaobing; Dastjerdi, M Hadi Tavakoli; Mi, Zetian; Plant, David V

2013-08-12

We report on theoretical and experimental investigation of azimuthal and longitudinal modes in rolled-up microtubes at telecom wavelengths. These microtubes are fabricated by selectively releasing a coherently strained InGaAs/GaAs bilayer. We apply planar waveguide method and a quasi-potential model to analyze the azimuthal and longitudinal modes in the microtubes near 1550 nm. Then we demonstrate these modes in transmission spectrum by evanescent light coupling. The experimental observations agree well with the calculated results. Surface-scattering-induced mode splitting is also observed in both transmission and reflection spectra at ~1600 nm. The mode splitting is in essence the non-degeneracy of clockwise and counter-clockwise whispering-gallery modes of the microtubes. This study is significant for understanding the physics of modes in microtubes and other microcavities with three-dimensional optical confinement, as well as for potential applications such as microtube-based photonic integrated devices and sensing purposes.

Spirituality: a cultural strength for African American mothers with HIV.

PubMed

Polzer Casarez, Rebecca L; Miles, Margaret Shandor

2008-05-01

The purpose of this study was to describe how spirituality affected the lives of African American mothers with Human Immunodeficiency Virus (HIV) in the context of coping. This qualitative descriptive study used secondary data of interviews from a larger longitudinal study of parental caregiving of infants seropositive for HIV. Participants were 38 African American mothers with HIV. Data from longitudinal semi-structured interviews were analyzed using content analysis. The women dealt with the stresses of HIV through a relationship with God. Two domains explain this relationship: God in control and God requires participation. The benefits of their relationship with God were a decrease in stress and worry about their own health and that of their infants. It is important for nurses working with mothers with HIV to acknowledge their spirituality and assess how spirituality helps them cope with and manage their illness.

Stability and Change in Health Insurance Among Older Mexican Americans: Longitudinal Evidence From the Hispanic Established Populations for Epidemiologic Study of the Elderly

PubMed Central

Angel, Ronald J.; Angel, Jacqueline L.; Markides, Kyriakos S.

2002-01-01

Objectives. This study examined the association between health insurance coverage, medical care use, limitations in activities of daily living, and mortality among older Mexican-origin individuals. Methods. We analyzed longitudinal data from the Hispanic Established Populations for Epidemiologic Study of the Elderly (H-EPESE). Results. The uninsured tend to be younger, female, poor, and foreign born. They report fewer health care visits, are less likely to have a usual source of care, and more often receive care in Mexico. Conversely, those with private health insurance are economically better off and use more health care services. Over time, the data reveal substantial changes in type of insurance coverage. Conclusions. The data reveal serious vulnerabilities among older Mexican Americans that result from a lack of private Medigap supplemental coverage. (Am J Public Health. 2002;92:1264–1271) PMID:12144982

Religiousness and Longitudinal Trajectories in Elders' Functional Status

PubMed Central

Park, Nan Sook; Klemmack, David L.; Roff, Lucinda L.; Parker, Michael W.; Koenig, Harold G.; Sawyer, Patricia; Allman, Richard M.

2010-01-01

The purpose of this study was to examine the effects of religiousness on the trajectories of difficulties with activities of daily living (ADLs) and instrumental ADLs (IADLs) in community-dwelling older adults over a three-year period. Seven waves of data from the University of Alabama at Birmingham Study of Aging were analyzed using a hierarchical linear modeling method. The study was based on the 784 participants who completed interviews every six months between December 1999 and February 2004. Frequent religious service attendance was associated with fewer ADL difficulties and IADL difficulties at baseline. Furthermore, religious service attendance predicted slower increases for frequent churchgoers and steeper increases for less frequent churchgoers in IADL difficulties, controlling for variables related to demographics and resources. Religious service attendance was independently associated with ADL and IADL difficulties cross-sectionally. However, significant protective effects of religious service attendance were identified longitudinally only for the IADL trajectory. PMID:20485460

[Comparative study of N, P output and eutrophication risk in runoff water in cross ridge and longitudinal ridge].

PubMed

Yu, Xing-Xiu; Ma, Qian; Liu, Qian-Jin; Lü, Guo-An

2011-02-01

Field in-situ rainfall simulation tests with two rainfall intensities (40 mm x h(-1) and 70 mm x h(-1)), which were conducted at typical sloping cropland in Yimeng mountainous area, were designed to analyze the output characteristics of dissolved inorganic nitrogen, Inorganic-N (NO3(-)-N, NH4(+) -N) and dissolved phosphorus (DP) in runoff water, as well as to compare the eutrophication risk in this water by calculating three ratios of Inorganic-N/DP, NO3(-) -N/DP, and NH4(+)-N/DP, respectively, in cross ridge and longitudinal ridge tillage methods. Results showed that, under the same rainfall intensity, the DP level in runoff water was higher in cross ridge than longitudinal ridge, while the change of different Inorganic-N level between the two tillage methods were not consistent. Cross ridge could effectively reduce runoff and the output rate of Inorganic-N and DP when compared to the longitudinal ridge tillage, which would be more outstanding with the increases of rainfall intensities. The losses of Inorganic-N and DP in runoff water were 43% and 5% less, respectively, in cross ridge than longitudinal ridge at the 40 mm x h(-1) rainfall intensity, and were 68% and 55%, respectively, at 70 mm x h(-1). The higher Inorganic-N/DP and NO3(-) -N/DP ratios suggest that runoff water from either cross ridge or longitudinal ridge tillage have a certain eutrophication risk, which present an increasing trend during the precipitation-runoff process. Compared with longitudinal ridge, cross ridge can not only hinder the increasing trend of eutrophication risk, but also can significantly lower it, and thus effectively reduce the effect of sloping cropland runoff on the eutrophication processes of receiving waters.

Aging Baby Boomers and the Rising Cost of Chronic Back Pain: Secular Trend Analysis of Longitudinal Medical Expenditures Panel Survey Data for Years 2000 to 2007

PubMed Central

Smith, Monica; Davis, Matthew A.; Stano, Miron; Whedon, James M.

2013-01-01

Objectives The purposes of this study were to analyze data from the longitudinal Medical Expenditures Panel Survey (MEPS) to evaluate the impact of an aging population on secular trends in back pain and chronicity and to provide estimates of treatment costs for patients who used only ambulatory services. Methods Using the MEPS 2-year longitudinal data for years 2000 to 2007, we analyzed data from all adult respondents. Of the total number of MEPS respondent records analyzed (N = 71 838), we identified 12 104 respondents with back pain and further categorized 3842 as chronic cases and 8262 as nonchronic cases. Results Secular trends from the MEPS data indicate that the prevalence of back pain has increased by 29%, whereas chronic back pain increased by 64%. The average age among all adults with back pain increased from 45.9 to 48.2 years; the average age among adults with chronic back pain increased from 48.5 to 52.2 years. Inflation-adjusted (to 2010 dollars) biennial expenditures on ambulatory services for chronic back pain increased by 129% over the same period, from $15.6 billion in 2000 to 2001 to $35.7 billion in 2006 to 2007. Conclusion The prevalence of back pain, especially chronic back pain, is increasing. To the extent that the growth in chronic back pain is caused, in part, by an aging population, the growth will likely continue or accelerate. With relatively high cost per adult with chronic back pain, total expenditures associated with back pain will correspondingly accelerate under existing treatment patterns. This carries implications for prioritizing health policy, clinical practice, and research efforts to improve care outcomes, costs, and cost-effectiveness and for health workforce planning. PMID:23380209

Did the Family Health Strategy have an impact on indicators of hospitalizations for stroke and heart failure? Longitudinal study in Brazil: 1998-2013.

PubMed

Cavalcante, Denise de Fátima Barros; Brizon, Valéria Silva Cândido; Probst, Livia Fernandes; Meneghim, Marcelo de Castro; Pereira, Antonio Carlos; Ambrosano, Gláucia Maria Bovi

2018-01-01

The objective was to analyze whether socioeconomic factors related to the context and those related to the model of care-specifically the coverage of primary care by the Family Health Strategy (ESF)-had an impact on hospitalizations due to heart failure (HF) and stroke, in the State of São Paulo/Brazil between 1998 and 2013. A longitudinal ecological study involving 645 municipalities was conducted in the state of São Paulo/Brazil from 1998 to 2013, using the Hospital Information System (SIH-DataSUS database). The hospitalizations for primary care sensitive conditions: Stroke and heart failure (HF) that correspond to the International Classification of Diseases (ICD 10): I50, I63 to I67; I69, G45 to G46 were analyzed longitudinally during the period indicated regarding the percentage of people covered by the Family Health Program (PSF) adjusted for confounders (population size, gross domestic product -GDP and human development index- HDI). There was a significant decrease in the number of hospitalizations for heart failure and stroke per 10000 (inhabitants) in the period (p <0.0001), with a significant relationship with increased proportion of ESF (p <0.0001), and this remained significant even when possible confounders (population size, GDP and HDI) were included in the model (p <0.0001). GDP per capita was close to or higher than that if many European countries, which shows the relevance of the study. The health care model based on the Family Health Strategy positively impacted hospitalization indicators for heart failure and stroke, indicating that this model is effective in the prevention of primary care sensitive conditions.

Three Approaches to Modeling Gene-Environment Interactions in Longitudinal Family Data: Gene-Smoking Interactions in Blood Pressure.

PubMed

Basson, Jacob; Sung, Yun Ju; de Las Fuentes, Lisa; Schwander, Karen L; Vazquez, Ana; Rao, Dabeeru C

2016-01-01

Blood pressure (BP) has been shown to be substantially heritable, yet identified genetic variants explain only a small fraction of the heritability. Gene-smoking interactions have detected novel BP loci in cross-sectional family data. Longitudinal family data are available and have additional promise to identify BP loci. However, this type of data presents unique analysis challenges. Although several methods for analyzing longitudinal family data are available, which method is the most appropriate and under what conditions has not been fully studied. Using data from three clinic visits from the Framingham Heart Study, we performed association analysis accounting for gene-smoking interactions in BP at 31,203 markers on chromosome 22. We evaluated three different modeling frameworks: generalized estimating equations (GEE), hierarchical linear modeling, and pedigree-based mixed modeling. The three models performed somewhat comparably, with multiple overlaps in the most strongly associated loci from each model. Loci with the greatest significance were more strongly supported in the longitudinal analyses than in any of the component single-visit analyses. The pedigree-based mixed model was more conservative, with less inflation in the variant main effect and greater deflation in the gene-smoking interactions. The GEE, but not the other two models, resulted in substantial inflation in the tail of the distribution when variants with minor allele frequency <1% were included in the analysis. The choice of analysis method should depend on the model and the structure and complexity of the familial and longitudinal data. © 2015 WILEY PERIODICALS, INC.

A Report of Neuropsychological Differentation and De-Differentation in Very Young Children in Conflict with Special Reference to Autism.

ERIC Educational Resources Information Center

Massie, Henry N.; And Others

Longitudinal studies of mother-child interactions for the third trimester of pregnancy to age 4 are described. The effort is aimed at analyzing early childhood data to determine stability of mother-infant interaction, correlations among mothers' character as defined by adaptive and maladaptive defenses, major conflicts, sense of reality, and…

Gender Differences in the Consistency of Middle School Students' Interest in Engineering and Science Careers

ERIC Educational Resources Information Center

Ing, Marsha; Aschbacher, Pamela R.; Tsai, Sherry M.

2014-01-01

This longitudinal study analyzes survey responses in seventh, eighth, and ninth grade from diverse public school students (n = 482) to explore gender differences in engineering and science career preferences. Females were far more likely to express interest in a science career (31%) than an engineering career (13%), while the reverse was true for…

Home and Parenting Resources Available to Siblings Depending on Their Birth Intention Status

ERIC Educational Resources Information Center

Barber, Jennifer S.; East, Patricia L.

2009-01-01

This study examines the differential availability of family and parenting resources to children depending on their birth planning status. The National Longitudinal Survey of Youth data were analyzed, 3,134 mothers and their 5,890 children (M = 7.1 years, range = 1 month-14.8 years), of whom 63% were intended at conception, 27% were mistimed, and…

The Role of Foreign Domestic Helpers in Hong Kong Chinese Children's English and Chinese Skills: A Longitudinal Study

ERIC Educational Resources Information Center

Dulay, Katrina May; Tong, Xiuhong; McBride, Catherine

2017-01-01

We investigated the influence of nonparental caregivers, such as foreign domestic helpers (FDH), on the home language spoken to the child and its implications for vocabulary and word reading development in Cantonese- and English-speaking bilingual children. Using data collected from ages 5 to 9, we analyzed Chinese vocabulary, Chinese character…

A Three Day Dietary Survey of Piute Preschool Children in Inyo County, Calif.

ERIC Educational Resources Information Center

Lewis, Jane S.; And Others

As part of a longitudinal study of Piute Indian children being conducted by Children's Hospital, Los Angeles, 3-day dietary-intake records of 23 Piute Indian preschool children in Inyo County, California, were analyzed according to 4 food groups. As reported, results indicated that 5 or 6 food groups should be used if intake results of vitamins C…

Availability of Reproductive Health Care Services at Schools and Subsequent Birth Outcomes among Adolescent Mothers

ERIC Educational Resources Information Center

Madkour, Aubrey S.; Xie, Yiqiong; Harville, Emily W.

2016-01-01

Background: Adverse birth outcomes are more common among adolescent versus adult mothers, but little is known about school-based services that may improve birth outcomes in this group. Methods: Data from Waves I and IV of the National Longitudinal Study of Adolescent Health were analyzed. Girls and women who gave birth to singleton live infants…

"Why Do We Know Hebrew and They Do Not Know Arabic?" Children's Meta-Linguistic Talk in Bilingual Preschool

ERIC Educational Resources Information Center

Schwartz, Mila; Gorbatt, Naomi

2016-01-01

Language-focused listening to young children's talk provides insight into their internal thinking mechanisms regarding language as they engage in language learning. The aim of this exploratory longitudinal study was to examine and analyze children's meta-linguistic talk and its main characteristics in a bilingual Arabic-Hebrew-speaking preschool.…

A Longitudinal Investigation of Content, Resources, and Instructional Approaches in a Basal Reading Series within a Research and Policy Context

ERIC Educational Resources Information Center

Kenavey, Lori Ann

2016-01-01

Basals have played an important role in classroom instruction for almost 200 years. Historically, basal programs have been influenced by both important research and policy reports. This study analyzed one publishing company's basal program across seven editions in order to trace the interaction of research, policy, and publication. Teacher's…

Characteristics of Vocal Fold Vibrations in Vocally Healthy Subjects: Analysis with Multi-Line Kymography

ERIC Educational Resources Information Center

Yamauchi, Akihito; Imagawa, Hiroshi; Sakakibara, Ken-Ichi; Yokonishi, Hisayuki; Nito, Takaharu; Yamasoba, Tatsuya; Tayama, Niro

2014-01-01

Purpose: In this study, the authors aimed to analyze longitudinal data from high-speed digital images in normative subjects using multi-line kymography. Method: Vocally healthy subjects were divided into young (9 men and 17 women; M[subscript age] = 27 years) and older groups (8 men and 12 women; M[subscript age] = 73 years). From high-speed…

Stability of Maternal Discipline Practices and the Quality of Mother-Child Interaction during Toddlerhood

ERIC Educational Resources Information Center

Huang, Keng-Yen; Caughy, Margaret O'Brien; Lee, Li-Ching; Miller, Therese; Genevro, Janice

2008-01-01

This study examined the stability of maternal punitive/high-power discipline (PD) and inductive/authoritative discipline (ID) over the second and third years of life and the effect of maternal discipline on quality of mother-child interactions. Data from a longitudinal sample with 179 mother-toddler dyads were analyzed, and selected factors (i.e.,…

A Longitudinal Evaluation of the Intermediate-Term Impact of the "Money Smart" Financial Education Curriculum upon Consumers' Behavior and Confidence

ERIC Educational Resources Information Center

Federal Deposit Insurance Corporation, 2007

2007-01-01

Using data collected from a pre-training survey, post-training survey, and telephone follow-up survey, this study analyzes the impact of the Money Smart financial education curriculum upon the financial opinions and behaviors of course participants during the survey period. The data indicate that Money Smart financial education training positively…

Middle School Students' Writing and Feedback in a Cloud-Based Classroom Environment

ERIC Educational Resources Information Center

Zheng, Binbin; Lawrence, Joshua; Warschauer, Mark; Lin, Chin-Hsi

2015-01-01

Individual writing and collaborative writing skills are important for academic success, yet are poorly taught in K-12 classrooms. This study examines how sixth-grade students (n = 257) taught by two teachers used Google Docs to write and exchange feedback. We used longitudinal growth models to analyze a large number of student writing samples…

Understanding Differences in Black and White Child Poverty Rates. A Report of the Heritage Center for Data Analysis.

ERIC Educational Resources Information Center

Rector, Robert; Johnson, Kirk A.; Fagan, Patrick F.

This study uses National Longitudinal Survey of Youth (NLSY) data to analyze differences in black and white child poverty. The NLSY documents family income and underlying conditions such as employment, educational attainment, welfare use, and marriage or divorce. This analysis examines: time in poverty, time on welfare, time in a single parent…

Cost-minimization analysis in the treatment of spasticity in children with cerebral palsy with botulinum toxin type A: an observational, longitudinal, retrospective study.

PubMed

Tapias, Gloria; García-Romero, Mar; Crespo, Carlos; Cuesta, Maribel; Forné, Carles; Pascual-Pascual, Samuel Ignacio

2016-09-01

Cost-minimization analysis of onabotulinumtoxinA and abobotulinumtoxinA, taking into account the real dose administered to children with spasticity associated with dynamic equinus foot deformity due to cerebral palsy. A single centre, observational, longitudinal, and retrospective study which included spastic paediatric patients aged 2-to-18-years and treated with onabotulinumtoxinA or abobotulinumtoxinA from December 1995 to October 2012, in the Paediatric Neurology Unit of a first-level Spanish hospital. A longitudinal analysis of spasticity severity was made to confirm the similar efficacy of both treatments. Cost minimization was analyzed using the dose administered and the direct costs (pharmacological and medical visits costs) from the perspective of the National Health System (in euros from 2016). We analyzed 895 patients with paediatric spasticity: 543 were treated only with onabotulinumtoxinA, 292 only with abobotulinumtoxinA, and 60 with both treatments. The mean doses administered were 5.44 U/kg (SD = 2.17) for onabotulinumtoxinA, and 14.73 U/kg (5.26) for abobotulinumto xinA. The total annual direct cost (pharmacological and medical visits) was € 839.56 for onabotulinumtoxinA and € 631.23 for abobotulinumtoxinA, which represents a difference of € 208.34 per year in favour of treatment with abobotulinumtoxinA. It has been demonstrated that in real clinical practice, the cost per patient and year for treatment of paediatric spasticity was lower when abobotulinumtoxinA was used. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

Relationship between white matter lesions and regional cerebral blood flow changes during longitudinal follow up in Alzheimer's disease.

PubMed

Hanaoka, Takuya; Kimura, Noriyuki; Aso, Yasuhiro; Takemaru, Makoto; Kimura, Yuki; Ishibashi, Masato; Matsubara, Etsuro

2016-07-01

The aim of the present study was to evaluate the relationship between baseline white matter lesions (WML) and changes in regional cerebral blood flow during longitudinal follow up of patients with Alzheimer's disease (AD). A total of 38 patients with AD were included in the study (16 men, 22 women; mean age 77.8 years). All patients were evaluated using the Mini-Mental State Examination and brain perfusion single-photon emission computed tomography at baseline with an approximately 2-year follow up. The patients were divided into two subgroups according to the presence of WML on magnetic resonance imaging. Single-photon emission computed tomography data were analyzed using a voxel-by-voxel group analysis with Statistical Parametric Mapping 8 and region of interest analysis using FineSRT. Changes in Mini-Mental State Examination scores and regional cerebral blood flow were analyzed using the Wilcoxon signed-rank test. Mean Mini-Mental State Examination scores in AD patients with WML significantly decreased from 19.4 ± 4.8 to 15.5 ± 6.5 (P = 0.003). Statistical Parametric Mapping 8 and FineSRT analysis showed more severe and widespread regional cerebral blood flow reduction, mainly in the frontal and mesial temporal regions in AD patients with WML compared with those without WML. Baseline WML could predict a rapid progression of cognitive and brain functional impairment during longitudinal follow up in AD. Geriatr Gerontol Int 2016; 16: 836-842. © 2015 Japan Geriatrics Society.

Turbulent statistics in flow field due to interaction of two plane parallel jets

NASA Astrophysics Data System (ADS)

Bisoi, Mukul; Das, Manab Kumar; Roy, Subhransu; Patel, Devendra Kumar

2017-12-01

Turbulent characteristics of flow fields due to the interaction of two plane parallel jets separated by the jet width distance are studied. Numerical simulation is carried out by large eddy simulation with a dynamic Smagorinsky model for the sub-grid scale stresses. The energy spectra are observed to follow the -5/3 power law for the inertial sub-range. A proper orthogonal decomposition study indicates that the energy carrying large coherent structures is present close to the nozzle exit. It is shown that these coherent structures interact with each other and finally disintegrate into smaller vortices further downstream. The turbulent fluctuations in the longitudinal and lateral directions are shown to follow a similarity. The mean flow at the same time also maintains a close similarity. Prandtl's mixing length, the Taylor microscale, and the Kolmogorov length scales are shown along the lateral direction for different downstream locations. The autocorrelation in the longitudinal and transverse directions is seen to follow a similarity profile. By plotting the probability density function, the skewness and the flatness (kurtosis) are analyzed. The Reynolds stress anisotropy tensor is calculated, and the anisotropy invariant map known as Lumley's triangle is presented and analyzed.

Evaluating the dose effects of a longitudinal micro-CT study on pulmonary tissue in C57BL/6 mice

NASA Astrophysics Data System (ADS)

Detombe, Sarah A.; Dunmore-Buyze, Joy; Petrov, Ivailo E.; Drangova, Maria

2012-03-01

Background: Micro-computed tomography offers numerous advantages for small animal imaging, including the ability to monitor the same animals throughout a longitudinal study. However, concerns are often raised regarding the effects of x-ray dose accumulated over the course of the experiment. In this study, we scan C57BL/6 mice multiple times per week for six weeks, to determine the effect of the cumulative dose on pulmonary tissue at the end of the study. Methods/Results: C57BL/6 male mice were split into two groups (irradiated group=10, control group=10). The irradiated group was scanned (80kVp/50mA) each week for 6 weeks; the weekly scan session had three scans. This resulted in a weekly dose of 0.84 Gy, and a total study dose of 5.04 Gy. The control group was scanned on the final week. Scans from weeks 1 and 6 were reconstructed and analyzed: overall, there was no significant difference in lung volume or lung density between the control group and the irradiated group. Similarly, there were no significant differences between the week 1 and week 6 scans in the irradiated group. Histological samples taken from excised lung tissue also showed no evidence of inflammation or fibrosis in the irradiated group. Conclusion: This study demonstrates that a 5 Gy x-ray dose accumulated over six weeks during a longitudinal micro-CT study has no significant effects on the pulmonary tissue of C57BL/6 mice. As a result, the many advantages of micro- CT imaging, including rapid acquisition of high-resolution, isotropic images in free-breathing mice, can be taken advantage of in longitudinal studies without concern for negative dose-related effects.

Domestic violence and treatment seeking: a longitudinal study of low-income women and mental health/substance abuse care.

PubMed

Cheng, Tyrone C; Lo, Celia C

2014-01-01

A study with 591 low-income women examined domestic violence's role in treatment seeking for mental health or substance abuse problems. (The women resided in one of two California counties.) Following Aday's behavioral model of health services utilization, the secondary data analysis considered the women's need, enabling, and predisposing factors. Generalized estimating equations analyzed the women's longitudinal records of treatment seeking. Results showed that those in the sample who were likely to seek treatment had experienced three or more controlling behaviors and only one abusive behavior. Multivariate data analysis showed treatment-seeking women were likely to be white and older; responsible for few dependent children; not graduates of high school; employed; not participating in Medicaid; diagnosed; and perceiving a need for treatment. The implications of these results for services and policies are discussed.

Patient-Related Benefits for Adults with Cochlear Implantation: A Multicultural Longitudinal Observational Study

PubMed Central

Lenarz, Thomas; Muller, Lida; Czerniejewska-Wolska, Hanna; Vallés Varela, Hector; Orús Dotú, César; Durko, Marcin; Huarte Irujo, Alicia; Piszczatowski, Bartosz; Zadrożniak, Marek; Irwin, Colin; Graham, Petra L.; Wyss, Josie

2017-01-01

Objectives To assess subjectively perceived, real-world benefits longitudinally for unilateral cochlear implant (CI) recipients in a multinational population treated routinely. To identify possible predictors of self-reported benefits. Design This was a prospective, multicenter, repeated-measures study. Self-assessment of performance at preimplantation and postimplantation at 1, 2, and 3 years using standardized, validated, local language versions of the Speech, Spatial, and Qualities of Hearing Scale (SSQ), and the Health Utilities Index Mark 3 (HUI3) was performed. Outcomes were analyzed using a longitudinal mixed-effects model incorporating country effect. Patient demographics were explored for associations with change over time. Subjects Two hundred ninety-one routinely treated, unilateral CI recipients, aged 137–81 years, from 9 clinics across 4 countries. Results Highly significant improvements were observed for all outcome measures (p < 0.0001). Postimplantation, mean outcome scores remained stable beyond 1 year, with notable individual variability. A significant association for one or more outcomes with preimplantation contralateral hearing aid use, telephone use, age at implantation, implantation side, preimplantation comorbidities, dizziness, and tinnitus was observed (p < 0.004). Conclusions Longitudinal benefits of CI treatment can be measured using clinically standardized self-assessment tools to provide a holistic view of patient-related benefits in routine clinical practice for aggregated data from multinational populations. Self-reported outcomes can provide medical-based evidence regarding CI treatment to support decision-making by health service providers. PMID:28719901

Order-restricted inference for multivariate longitudinal data with applications to the natural history of hearing loss.

PubMed

Rosen, Sophia; Davidov, Ori

2012-07-20

Multivariate outcomes are often measured longitudinally. For example, in hearing loss studies, hearing thresholds for each subject are measured repeatedly over time at several frequencies. Thus, each patient is associated with a multivariate longitudinal outcome. The multivariate mixed-effects model is a useful tool for the analysis of such data. There are situations in which the parameters of the model are subject to some restrictions or constraints. For example, it is known that hearing thresholds, at every frequency, increase with age. Moreover, this age-related threshold elevation is monotone in frequency, that is, the higher the frequency, the higher, on average, is the rate of threshold elevation. This means that there is a natural ordering among the different frequencies in the rate of hearing loss. In practice, this amounts to imposing a set of constraints on the different frequencies' regression coefficients modeling the mean effect of time and age at entry to the study on hearing thresholds. The aforementioned constraints should be accounted for in the analysis. The result is a multivariate longitudinal model with restricted parameters. We propose estimation and testing procedures for such models. We show that ignoring the constraints may lead to misleading inferences regarding the direction and the magnitude of various effects. Moreover, simulations show that incorporating the constraints substantially improves the mean squared error of the estimates and the power of the tests. We used this methodology to analyze a real hearing loss study. Copyright © 2012 John Wiley & Sons, Ltd.

[Patient readmission for surgical site infection: integrative review].

PubMed

Machado, Lilian; Turrini, Ruth N T; Siqueira, Ana L

2013-02-01

Surgical site infections (SSI) represent an inherent risk after surgical procedures associated both to the surgical procedure and to the patient clinical conditions. To analyze in an integrative review the studies related to patient readmission due to SSI. The review was carried out by LILACS, CINHAL, MEDLINE and COCHRANE databases and articles published from 1966 to 2010 were selected. It was analyzed 13 studies classified as transversal (7), cohort (4) and longitudinal (2). Few studies analyzed only the readmissions related to the SSI. Time to define the readmission ranged from 28 to 90 days after surgery and studies related to orthopedic procedures were more frequent. The ISS readmission rates were lower than 5%. The main aetiological agents isolated from ISS were Staphylococcus aureus and coagulase-negative staphylococci. Monitoring readmissions due to SSI could contribute to dimension the occurrence of ISS post-discharge, once about half of the SSI post-discharge was diagnosed at the readmission moment.

Relativistic longitudinal self-compression of ultrashort time-domain hollow Gaussian pulses in plasma

NASA Astrophysics Data System (ADS)

Cao, Xiaochao; Fang, Feiyun; Wang, Zhaoying; Lin, Qiang

2017-10-01

We report a study on dynamical evolution of the ultrashort time-domain dark hollow Gaussian (TDHG) pulses beyond the slowly varying envelope approximation in homogenous plasma. Using the complex-source-point model, an analytical formula is proposed for describing TDHG pulses based on the oscillating electric dipoles, which is the exact solution of the Maxwell's equations. The numerical simulations show the relativistic longitudinal self-compression (RSC) due to the relativistic mass variation of moving electrons. The influences of plasma oscillation frequency and collision effect on dynamics of the TDHG pulses in plasma have been considered. Furthermore, we analyze the evolution of instantaneous energy density of the TDHG pulses on axis as well as the off axis condition.

In Vivo Brillouin Analysis of the Aging Crystalline Lens

PubMed Central

Besner, Sebastien; Scarcelli, Giuliano; Pineda, Roberto; Yun, Seok-Hyun

2016-01-01

Purpose To analyze the age dependence of the longitudinal modulus of the crystalline lens in vivo using Brillouin scattering data in healthy subjects. Methods Brillouin scans were performed along the crystalline lens in 56 eyes from 30 healthy subjects aged from 19 to 63 years. Longitudinal elastic modulus was acquired along the sagittal axis of the lens with a transverse and axial resolution of 4 and 60 μm, respectively. The relative lens stiffness was computed, and correlations with age were analyzed. Results Brillouin axial profiles revealed nonuniform longitudinal modulus within the lens, increasing from a softer periphery toward a stiffer central plateau at all ages. The longitudinal modulus at the central plateau showed no age dependence in a range of 19 to 45 years and a slight decrease with age from 45 to 63 years. A significant intersubject variability was observed in an age-matched analysis. Importantly, the extent of the central stiff plateau region increased steadily over age from 19 to 63 years. The slope of change in Brillouin modulus in the peripheral regions were nearly age-invariant. Conclusions The adult human lens showed no measurable age-related increase in the peak longitudinal modulus. The expansion of the stiff central region of the lens is likely to be the major contributing factor to age-related lens stiffening. Brillouin microscopy may be useful in characterizing the crystalline lens for the optimization of surgical or pharmacological treatments aimed at restoring accommodative power. PMID:27699407

Participation in an Intensive Longitudinal Study with Weekly Web Surveys Over 2.5 Years

PubMed Central

Barber, Jennifer; Kusunoki, Yasamin; Schulz, Paul

2016-01-01

Background Technological advances have made it easier for researchers to collect more frequent longitudinal data from survey respondents via personal computers, smartphones, and other mobile devices. Although technology has led to an increase in data-intensive longitudinal studies, little is known about attrition from such studies or the differences between respondents who complete frequently administered surveys in a timely manner, and respondents who do not. Objective We examined respondent characteristics and behaviors associated with continued and on-time participation in a population-based intensive longitudinal study, using weekly web-based survey interviews over an extended period. Methods We analyzed data from the Relationship Dynamics and Social Life study, an intensive longitudinal study that collected weekly web-based survey interviews for 2.5 years from 1003 18- and 19-year-olds to investigate factors shaping the dynamics of their sexual behavior, contraceptive use, and pregnancies. Results Ordinary least squares and logistic regression analyses showed background respondent characteristics measured at baseline were associated with the number of days respondents remained enrolled in the study, the number of interviews they completed, and the odds that they were late completing interviews. In addition, we found that changes in pregnancy-related behaviors reported in the weekly interviews were associated with late completion of interviews. Specifically, after controlling for sociodemographic, personality, contact information, and prior experience variables, we found that weekly reports such as starting to have sex (odds ratio [OR] 1.17, 95% CI 1.03-1.32, P=.01), getting a new partner (OR 1.76, 95% CI 1.53-2.03, P<.001), stopping the use of contraception (OR 1.28, 95% CI 1.10-1.49, P=.001), and having a new pregnancy (OR 5.57, 95% CI 4.26-7.29, P<.001) were significantly associated with late survey completion. However, young women who reported changes in pregnancy-related behaviors also had lower levels of study attrition, and completed more interviews overall, than did their counterparts. Conclusions We found that measures of participation in a longitudinal study with weekly web surveys varied not only by respondent characteristics, but also by behaviors measured across the surveys. Our analyses suggest that respondents who experience the behaviors measured by the study may maintain higher participation levels than respondents who do not experience those behaviors. PMID:27338859

Homebound older persons: Prevalence, characteristics, and longitudinal predictors

PubMed Central

Cohen-Mansfield, Jiska; Shmotkin, Dov; Hazan, Haim

2011-01-01

The current study examines the prevalence and correlates of homebound status aiming to elucidate the predictors and implications of being homebound. Analyzed sample was drawn from two representative cohorts of older persons in Israel, including 1191 participants (mean age = 83.10 ± 5.3 years) of the first wave of the Cross-Sectional and Longitudinal Aging Study (CALAS) and 418 participants (mean age = 83.13 ± 5.2) of the Israeli Multidisciplinary Aging Study (IMAS). Cross-sectional and longitudinal analyses were conducted. Homebound prevalence rates of 17.7% -19.5% were found. Homebound participants tended to be older, female, have obese or underweight body mass index (BMI), poorer health, lower functional status, less income, higher depressed affect, were significantly lonelier (in CALAS), and more likely to have stairs and no elevators, than their counterparts. Predictors of becoming homebound include low functional IADL status, having stairs and no elevator (in both cohorts), old age, female gender, and being obese or underweight (in CALAS). The study shows homebound status is a prevalent problem in old-old Israelis. Economic and socio-demographic resources, environment, and function play a role in determining the older person's homebound status. Implications for preventing homebound status and mitigating its impact with regards to the Israeli context are discussed. PMID:21420181

A novel metadata management model to capture consent for record linkage in longitudinal research studies.

PubMed

McMahon, Christiana; Denaxas, Spiros

2017-11-06

Informed consent is an important feature of longitudinal research studies as it enables the linking of the baseline participant information with administrative data. The lack of standardized models to capture consent elements can lead to substantial challenges. A structured approach to capturing consent-related metadata can address these. a) Explore the state-of-the-art for recording consent; b) Identify key elements of consent required for record linkage; and c) Create and evaluate a novel metadata management model to capture consent-related metadata. The main methodological components of our work were: a) a systematic literature review and qualitative analysis of consent forms; b) the development and evaluation of a novel metadata model. We qualitatively analyzed 61 manuscripts and 30 consent forms. We extracted data elements related to obtaining consent for linkage. We created a novel metadata management model for consent and evaluated it by comparison with the existing standards and by iteratively applying it to case studies. The developed model can facilitate the standardized recording of consent for linkage in longitudinal research studies and enable the linkage of external participant data. Furthermore, it can provide a structured way of recording consent-related metadata and facilitate the harmonization and streamlining of processes.

Selling and buying sex: a longitudinal study of risk and protective factors in adolescence.

PubMed

Kaestle, Christine E

2012-06-01

Engaging in trading sex is associated with many co-occurring problems, including elevated risk for sexually transmitted infections. Various dimensions of social support from parents, schools, and mentors may be protective against sex trading and may ameliorate the impact of risk factors. This study analyzes data from respondents to Waves I and III of the National Longitudinal Study of Adolescent Health (Add Health) who had not participated in sex trading for money or drugs in Wave I so that risk and protective factors for first initiations of selling or buying sex could be examined longitudinally. About 2% of the study sample began selling sex and about 2% began buying sex between Wave I and Wave III. The respondent's sex, race/ethnicity, history of sexual abuse, shoplifting, marijuana use, and experiences of homelessness or running away were significant predictors of trading sex (p < 0.05). Being happy at school was associated with lower selling of sex, and feeling part of school was associated with lower buying of sex even after controlling for demographics and risk factors (p < 0.05). Results indicate a need for early intervention for youth who experience sexual abuse or running away. Elements of school connectedness have a protective effect on selling and buying sex. Promoting school connectedness may advance public health goals.

Measuring the development of inhibitory control: The challenge of heterotypic continuity

PubMed Central

Petersen, Isaac T.; Hoyniak, Caroline P.; McQuillan, Maureen E.; Bates, John E.; Staples, Angela D.

2016-01-01

Inhibitory control is thought to demonstrate heterotypic continuity, in other words, continuity in its purpose or function but changes in its behavioral manifestation over time. This creates major methodological challenges for studying the development of inhibitory control in childhood including construct validity, developmental appropriateness and sensitivity of measures, and longitudinal factorial invariance. We meta-analyzed 198 studies using measures of inhibitory control, a key aspect of self-regulation, to estimate age ranges of usefulness for each measure. The inhibitory control measures showed limited age ranges of usefulness owing to ceiling/floor effects. Tasks were useful, on average, for a developmental span of less than 3 years. This suggests that measuring inhibitory control over longer spans of development may require use of different measures at different time points, seeking to measure heterotypic continuity. We suggest ways to study the development of inhibitory control, with overlapping measurement in a structural equation modeling framework and tests of longitudinal factorial or measurement invariance. However, as valuable as this would be for the area, we also point out that establishing longitudinal factorial invariance is neither sufficient nor necessary for examining developmental change. Any study of developmental change should be guided by theory and construct validity, aiming toward a better empirical and theoretical approach to the selection and combination of measures. PMID:27346906

Analyzing the Behavioral Differences between Students of Different Genders, Prior Knowledge and Learning Performance with an Educational MMORPG: A Longitudinal Case Study in an Elementary School

ERIC Educational Resources Information Center

Hou, Huei-Tse

2013-01-01

Many researchers have studied the effects of game-based learning (GBL) (eg, Annetta, Minogu, Holmes & Cheng, 2009; Kiili, 2007). However, empirical process analyses of long-term applications of GBL in a school setting are much less common. A process analysis of GBL in a school setting allows us to better understand the role of games in…

Influences on Adult Basic Skills. Factors Affecting the Development of Literacy and Numeracy from Birth to 37.

ERIC Educational Resources Information Center

Parsons, Samantha; Bynner, John

The factors influencing development of basic skills from birth to age 37 were examined by analyzing a sample of 1,700 people who were part of the National Child Development Study (NCDS), a longitudinal study in which data on more than 17,000 people who were born in Great Britain in a single week in 1958 were collected when they were 7, 11, 16, 23,…

Longitudinal Mediation Modeling of Unhealthy Behaviors as Mediators between Workplace Demands/Support and Depressive Symptoms

PubMed Central

Magnusson Hanson, Linda L.; Peristera, Paraskevi; Chungkham, Holendro Singh; Westerlund, Hugo

2016-01-01

Lifestyle has been regarded as a key pathway through which adverse psychosocial working characteristics can give rise to long-term health problems. The purpose of this study was to estimate the indirect/mediated effect of health behaviors in the longitudinal work characteristics-depression relationship. The analyses were based on the Swedish Longitudinal Occupational Survey of Health, including 3706 working participants with repeat survey measures on four occasions (2008, 2010, 2012 and 2014). Psychosocial work characteristics including demands and social support were analyzed in relation to depressive symptoms. Autoregressive longitudinal mediation models using structural equation modeling were used to estimate the intermediate effects of unhealthy behaviors including current smoking, excessive alcohol consumption, unhealthy diet and physical inactivity. Both workplace demands and social support were related to later depressive symptoms. In bivariate models we found no significant paths from workplace demands to health behaviors, but two out of three significant time-specific paths from workplace support to excessive drinking and from excessive drinking to depressive symptoms. Social support was also associated with subsequent unhealthy diet, and one path from unhealthy diet to depressive symptoms was found. However, despite indications of certain longitudinal relationships between psychosocial working conditions and health behaviors as well as between health behaviors and depressive symptoms, no significant intermediate effects were found (p>0.05). We conclude that changes in unhealthy behaviors over a period of two years are unlikely to act as strong intermediaries in the longitudinal relationship between job demands and depressive symptoms and between social support and depressive symptoms. PMID:28036376

Longitudinal Mediation Modeling of Unhealthy Behaviors as Mediators between Workplace Demands/Support and Depressive Symptoms.

PubMed

Magnusson Hanson, Linda L; Peristera, Paraskevi; Chungkham, Holendro Singh; Westerlund, Hugo

2016-01-01

Lifestyle has been regarded as a key pathway through which adverse psychosocial working characteristics can give rise to long-term health problems. The purpose of this study was to estimate the indirect/mediated effect of health behaviors in the longitudinal work characteristics-depression relationship. The analyses were based on the Swedish Longitudinal Occupational Survey of Health, including 3706 working participants with repeat survey measures on four occasions (2008, 2010, 2012 and 2014). Psychosocial work characteristics including demands and social support were analyzed in relation to depressive symptoms. Autoregressive longitudinal mediation models using structural equation modeling were used to estimate the intermediate effects of unhealthy behaviors including current smoking, excessive alcohol consumption, unhealthy diet and physical inactivity. Both workplace demands and social support were related to later depressive symptoms. In bivariate models we found no significant paths from workplace demands to health behaviors, but two out of three significant time-specific paths from workplace support to excessive drinking and from excessive drinking to depressive symptoms. Social support was also associated with subsequent unhealthy diet, and one path from unhealthy diet to depressive symptoms was found. However, despite indications of certain longitudinal relationships between psychosocial working conditions and health behaviors as well as between health behaviors and depressive symptoms, no significant intermediate effects were found (p>0.05). We conclude that changes in unhealthy behaviors over a period of two years are unlikely to act as strong intermediaries in the longitudinal relationship between job demands and depressive symptoms and between social support and depressive symptoms.

Methods to Limit Attrition in Longitudinal Comparative Effectiveness Trials: Lessons from the Lithium Use for Bipolar Disorder (LiTMUS) Study

PubMed Central

Sylvia, Louisa G.; Reilly-Harrington, Noreen A.; Leon, Andrew C.; Kansky, Christine I.; Ketter, Terence A.; Calabrese, Joseph R.; Thase, Michael E.; Bowden, Charles L.; Friedman, Edward S.; Ostacher, Michael J.; Iosifescu, Dan V.; Severe, Joanne; Nierenberg, Andrew A.

2013-01-01

Background High attrition rates which occur frequently in longitudinal clinical trials of interventions for bipolar disorder limit the interpretation of results. Purpose The aim of this article is to present design approaches that limited attrition in the Lithium Use for Bipolar Disorder (LiTMUS) Study. Methods LiTMUS was a 6-month randomized, longitudinal multi-site comparative effectiveness trial that examined bipolar participants who were at least mildly ill. Participants were randomized to either low to moderate doses of lithium or no lithium, in addition to other treatments needed for mood stabilization administered in a guideline-informed, empirically supported, and personalized fashion (N=283). Results Components of the study design that may have contributed to the low attrition rate of the study included use of: (1) an intent-to-treat design; (2) a randomized adjunctive single-blind design; (3) participant reimbursement; (4) intent-to-attend the next study visit (includes a discussion of attendance obstacles when intention is low); (5) quality care with limited participant burden; and (6) target windows for study visits. Limitations Site differences and the effectiveness and tolerability data have not been analyzed yet. Conclusions These components of the LiTMUS study design may have reduced the probability of attrition which would inform the design of future randomized clinical effectiveness trials. PMID:22076437

Longitudinal associations between key dietary behaviors and weight gain over time: transitions through the adolescent years.

PubMed

Laska, Melissa N; Murray, David M; Lytle, Leslie A; Harnack, Lisa J

2012-01-01

Previous studies have yielded inconsistent results when documenting the association between key dietary factors and adolescent weight change over time. The purpose of this study was to examine the extent to which changes in adolescent sugar-sweetened beverage (SSB), diet soda, breakfast, and fast-food consumption were associated with changes in BMI and percent body fat (PBF). This study analyzed data from a sample of 693 Minnesota adolescents followed over 2 years. Random coefficient models were used to examine the relationship between dietary intake and BMI and PBF and to separate cross-sectional and longitudinal associations. Adjusting for total physical activity, total energy intake, puberty, race, socioeconomic status, and age, cross-sectional findings indicated that for both males and females, breakfast consumption was significantly and inversely associated with BMI and PBF, and diet soda intake was significantly and positively associated with BMI and PBF among females. In longitudinal analyses, however, there were fewer significant associations. Among males there was evidence of a significant longitudinal association between SSB consumption and PBF; after adjustment for energy intake, an increase of one serving of SSB per day was associated with an increase of 0.7 units of PBF among males. This study adds to previous research through its methodological strengths, including adjustment for physical activity and energy intake assessed using state-of-the-art methods (i.e., accelerometers and 24-h dietary recalls), as well as its evaluation of both BMI and PBF. Additional research is needed to better understand the complex constellation of factors that contribute to adolescent weight gain over time.

Longitudinal weight gain in women identified with polycystic ovary syndrome: results of an observational study in young women.

PubMed

Teede, Helena J; Joham, Anju E; Paul, Eldho; Moran, Lisa J; Loxton, Deborah; Jolley, Damien; Lombard, Catherine

2013-08-01

Polycystic ovary syndrome (PCOS) affects 6-18% of women. The natural history of weight gain in women with PCOS has not been well described. Here we aimed to examine longitudinal weight gain in women with and without PCOS and to assess the association between obesity and PCOS prevalence. The observational study was set in the general community. Participants were women randomly selected from the national health insurance scheme (Medicare) database. Mailed survey data were collected by the Australian Longitudinal Study on Women's Health. Data from respondents to survey 4, aged 28-33 years (2006, n = 9,145) were analyzed. The main outcome measures were PCOS prevalence and body mass index (BMI). Self-reported PCOS prevalence was 5.8% (95% CI: 5.3%-6.4%). Women reporting PCOS had higher weight, mean BMI [2.5 kg/m(2) (95% CI: 1.9-3.1)], and greater 10-year weight gain [2.6 kg (95% CI: 1.2-4.0)]. BMI was the strongest correlate of PCOS status with every BMI increment increasing the risk of reporting PCOS by 9.2% (95% CI: 6%-12%). This community based observational study with longitudinal reporting of weight shows that weight, BMI, and 10-year weight gain were higher in PCOS. We report the novel finding that obesity and greater weight gain are significantly associated with PCOS status. Considering the prevalence, major health and economic burden of PCOS, the increasing weight gain in young women, and established benefits of weight loss, these results have major public health implications. Copyright © 2012 The Obesity Society.

Influence of mother-daughter attachment on substance use: a longitudinal study of a Latina community-based sample.

PubMed

De La Rosa, Mario; Huang, Hui; Rojas, Patria; Dillon, Frank R; Lopez-Quintero, Catalina; Li, Tan; Ravelo, Gira J

2015-03-01

Advancing our initial, cross-sectional study, which showed that adult Latinas' mother-daughter attachment relates to their substance use, the current, longitudinal study tests whether mother and daughter attachment scores at baseline predict their substance use over time. We analyzed data from a convenience sample of 133 Latina adult mothers (mean age = 52 years, SD = 10) and 133 Latina adult daughters (mean age = 27, SD = 9) at baseline and at 5-year and 6-year follow-ups after baseline (attrition rate = 16%). Multilevel longitudinal modeling was used to examine the effect of mother-daughter attachment at baseline on their substance use over time. Each unit of increase in the attachment score at baseline is associated with a 0.28 drink decrease in monthly alcohol use (p < .05) and a lower likelihood of being a heavy alcohol or other drug user [exp(β) = 0.97, p < .01] compared with average attachment score at baseline (M = 91.52, SD = 18.00). Time and older age at baseline are associated with decreased substance use. Being born outside the United States is associated with decreased risk of heavy alcohol or other drug use. Being a mother is associated with increased substance use. The findings of this longitudinal study on adult Latinas indicate that mother-daughter attachment has long-lasting effects on substance use trajectories among adult Latinas. Future research should focus on (a) investigating social and cultural factors mediating this relationship and (b) greater substance use among Latina mothers compared with daughters.

A longitudinal study of occlusal caries in Newark New Jersey school children: relationship between initial dental finding and the development of new lesions

PubMed Central

Markowitz, Kenneth; Fairlie, Karen; Ferrandiz, Javier; Nasri-Heir, Cibele

2012-01-01

Objective Dental caries is a significant public health problem especially amongst children from low-income backgrounds. This longitudinal study examined the development of new occlusal caries in 227 Newark, NJ children ages 10–18. The role of previous caries experience and the presence of occlusal white and dark lesions in predicting the development of new lesions were examined. Design At each visit, the patient’s teeth were given a visual-tactile examination and the subject’s decayed; missing and filled (DMFS) score was determined. Next, molars lacking probeable caries or restorations were examined using transillumination for occlusal white and dark spots. This examination was repeated periodically. A Cox proportional hazard was used to analyze data concerning the development of new occusal caries in molars. Results The longitudinal data indicates that patients who were caries free at visit-1 developed significantly fewer occlusal caries during the longitudinal study. The hazard ratio for subjects who had first-visit caries was 2.27 compared to caries free subjects. Intact molars with occlusal white or dark lesions had caries hazard ratios of 0.78 and 1.49 respectively, compared to molars lacking initial color changes. Conclusion Having a prior caries history places the subject at increased risk of developing future caries. Teeth with dark lesions but not white lesions are at significantly increased risk for developing decay. White lesions may represent remineralizing or slowly progressing lesions. The results of this study can help identify patients and tooth surfaces at risk for future occlusal decay. PMID:22841633

Influence of Mother–Daughter Attachment on Substance Use: A Longitudinal Study of a Latina Community-Based Sample

PubMed Central

De La Rosa, Mario; Huang, Hui; Rojas, Patria; Dillon, Frank R.; Lopez-Quintero, Catalina; Li, Tan; Ravelo, Gira J.

2015-01-01

Objective: Advancing our initial, cross-sectional study, which showed that adult Latinas’ mother–daughter attachment relates to their substance use, the current, longitudinal study tests whether mother and daughter attachment scores at baseline predict their substance use over time. Method: We analyzed data from a convenience sample of 133 Latina adult mothers (mean age = 52 years, SD = 10) and 133 Latina adult daughters (mean age = 27, SD = 9) at baseline and at 5-year and 6-year follow-ups after baseline (attrition rate = 16%). Multilevel longitudinal modeling was used to examine the effect of mother–daughter attachment at baseline on their substance use over time. Results: Each unit of increase in the attachment score at baseline is associated with a 0.28 drink decrease in monthly alcohol use (p < .05) and a lower likelihood of being a heavy alcohol or other drug user [exp(β) = 0.97, p < .01] compared with average attachment score at baseline (M = 91.52, SD = 18.00). Time and older age at baseline are associated with decreased substance use. Being born outside the United States is associated with decreased risk of heavy alcohol or other drug use. Being a mother is associated with increased substance use. Conclusions: The findings of this longitudinal study on adult Latinas indicate that mother–daughter attachment has long-lasting effects on substance use trajectories among adult Latinas. Future research should focus on (a) investigating social and cultural factors mediating this relationship and (b) greater substance use among Latina mothers compared with daughters. PMID:25785806

Longitudinal Data Systems to Support Data-Informed Decision Making: A Tri-State Partnership between Michigan, Minnesota, and Wisconsin. WCER Working Paper No. 2006-1

ERIC Educational Resources Information Center

Thorn, Christopher A.; Meyer, Robert H.

2006-01-01

The U.S. Department of Education recently held a competition for grants to support states in their efforts to build longitudinal data systems to track and analyze student and school performance. The Value-Added Research Center (VARC) at the Wisconsin Center for Education Research, University of Wisconsin-Madison, proposed a Tri-State Partnership…

PCA and vTEC climatology at midnight over mid-latitude regions

NASA Astrophysics Data System (ADS)

Natali, M. P.; Meza, A.

2017-12-01

The effect of the thermospheric vertical neutral wind on vertical total electron content (vTEC) variations including longitudinal anomaly, remaining winter anomaly, mid-latitude summer night anomaly, and semiannual anomaly is studied at mid-latitude regions around zero magnetic declination at midnight during high solar activity. By using the principal component analysis (PCA) numerical technique, this work studies the spatial and temporal variations of the ionosphere at midnight over mid-latitude regions during 2000-2002. PCA is applied to a time series of global vTEC maps produced by the International Global Navigation Satellite System (GNSS) Service. Four regions were studied in particular, each located at mid-latitude and approximately centered at zero magnetic declination, with two in the northern hemisphere and two in southern hemisphere, and all are located near and far from geomagnetic poles in each case. This technique provides an effective method to analyze the main ionospheric variabilities at mid-latitudes. PCA is also applied to the vTEC computed using the International Reference Ionosphere (IRI) 2012 model, to analyze the capability of this model to represent ionospheric variabilities at mid-latitude. Also, the Horizontal Wind Model 2007 (HWM07) is used to improve our climatology interpretation, by analyzing the relationship between vTEC and thermospheric wind, both quantitatively and qualitatively. At midnight, the behavior of mean vTEC values strongly responds to vertical wind variation, experiencing a decrease of about 10-15% with the action of the positive vertical component of the field-aligned neutral wind lasting for 2 h in all regions except for Oceania. Notable results include: a significant increase toward higher latitudes during summer in the South America and Asia regions, associated with the mid-latitude summer night anomaly, and an increase toward higher latitudes in winter in the North America and Oceania regions, highlighting the remnant effect of the winter anomaly. Finally, the longitudinal variations of east-west differences, named longitudinal anomaly, show maximum values in March for North America, in December for South America and Oceania, and are not shown for Asia. Our results show that at mid-latitudes regions, the IRI model represents midnight ionospheric mean values with a similar spatial distribution, but the values are always lower than those obtained by GNSS. The differences between IRI and GNSS results include: the longitudinal anomaly is characterized by a stronger semiannual variation in both North America and South America, with a maximum in the equinoxes, while for the Asian region, the behavior is almost constant throughout the years, and finally, there is an absence of the winter anomaly remnant.

The dark and bright sides of self-efficacy in predicting learning, innovative and risky performances.

PubMed

Salanova, Marisa; Lorente, Laura; Martínez, Isabel M

2012-11-01

The objective of this study is to analyze the different role that efficacy beliefs play in the prediction of learning, innovative and risky performances. We hypothesize that high levels of efficacy beliefs in learning and innovative performances have positive consequences (i.e., better academic and innovative performance, respectively), whereas in risky performances they have negative consequences (i.e., less safety performance). To achieve this objective, three studies were conducted, 1) a two-wave longitudinal field study among 527 undergraduate students (learning setting), 2) a three-wave longitudinal lab study among 165 participants performing innovative group tasks (innovative setting), and 3) a field study among 228 construction workers (risky setting). As expected, high levels of efficacy beliefs have positive or negative consequences on performance depending on the specific settings. Unexpectedly, however, we found no time x self-efficacy interaction effect over time in learning and innovative settings. Theoretical and practical implications within the social cognitive theory of A. Bandura framework are discussed.

A Bayesian Semiparametric Approach for Incorporating Longitudinal Information on Exposure History for Inference in Case-Control Studies

PubMed Central

Bhadra, Dhiman; Daniels, Michael J.; Kim, Sungduk; Ghosh, Malay; Mukherjee, Bhramar

2014-01-01

In a typical case-control study, exposure information is collected at a single time-point for the cases and controls. However, case-control studies are often embedded in existing cohort studies containing a wealth of longitudinal exposure history on the participants. Recent medical studies have indicated that incorporating past exposure history, or a constructed summary measure of cumulative exposure derived from the past exposure history, when available, may lead to more precise and clinically meaningful estimates of the disease risk. In this paper, we propose a flexible Bayesian semiparametric approach to model the longitudinal exposure profiles of the cases and controls and then use measures of cumulative exposure based on a weighted integral of this trajectory in the final disease risk model. The estimation is done via a joint likelihood. In the construction of the cumulative exposure summary, we introduce an influence function, a smooth function of time to characterize the association pattern of the exposure profile on the disease status with different time windows potentially having differential influence/weights. This enables us to analyze how the present disease status of a subject is influenced by his/her past exposure history conditional on the current ones. The joint likelihood formulation allows us to properly account for uncertainties associated with both stages of the estimation process in an integrated manner. Analysis is carried out in a hierarchical Bayesian framework using Reversible jump Markov chain Monte Carlo (RJMCMC) algorithms. The proposed methodology is motivated by, and applied to a case-control study of prostate cancer where longitudinal biomarker information is available for the cases and controls. PMID:22313248

Prediction of the effects of propeller operation on the static longitudinal stability of single-engine tractor monoplanes with flaps retracted

NASA Technical Reports Server (NTRS)

Weil, Joseph; Sleeman, William C , Jr

1949-01-01

The effects of propeller operation on the static longitudinal stability of single-engine tractor monoplanes are analyzed, and a simple method is presented for computing power-on pitching-moment curves for flap-retracted flight conditions. The methods evolved are based on the results of powered-model wind-tunnel investigations of 28 model configurations. Correlation curves are presented from which the effects of power on the downwash over the tail and the stabilizer effectiveness can be rapidly predicted. The procedures developed enable prediction of power-on longitudinal stability characteristics that are generally in very good agreement with experiment.

Reporting to Improve Reproducibility and Facilitate Validity Assessment for Healthcare Database Studies V1.0.

PubMed

Wang, Shirley V; Schneeweiss, Sebastian; Berger, Marc L; Brown, Jeffrey; de Vries, Frank; Douglas, Ian; Gagne, Joshua J; Gini, Rosa; Klungel, Olaf; Mullins, C Daniel; Nguyen, Michael D; Rassen, Jeremy A; Smeeth, Liam; Sturkenboom, Miriam

2017-09-01

Defining a study population and creating an analytic dataset from longitudinal healthcare databases involves many decisions. Our objective was to catalogue scientific decisions underpinning study execution that should be reported to facilitate replication and enable assessment of validity of studies conducted in large healthcare databases. We reviewed key investigator decisions required to operate a sample of macros and software tools designed to create and analyze analytic cohorts from longitudinal streams of healthcare data. A panel of academic, regulatory, and industry experts in healthcare database analytics discussed and added to this list. Evidence generated from large healthcare encounter and reimbursement databases is increasingly being sought by decision-makers. Varied terminology is used around the world for the same concepts. Agreeing on terminology and which parameters from a large catalogue are the most essential to report for replicable research would improve transparency and facilitate assessment of validity. At a minimum, reporting for a database study should provide clarity regarding operational definitions for key temporal anchors and their relation to each other when creating the analytic dataset, accompanied by an attrition table and a design diagram. A substantial improvement in reproducibility, rigor and confidence in real world evidence generated from healthcare databases could be achieved with greater transparency about operational study parameters used to create analytic datasets from longitudinal healthcare databases. © 2017 The Authors. Pharmacoepidemiology & Drug Safety Published by John Wiley & Sons Ltd.

Psychosocial factors and financial literacy.

PubMed

Murphy, John L

2013-01-01

This study uses data from the Health and Retirement Study (HRS) to analyze the psychological and social variables associated with financial literacy. The HRS is a nationally representative longitudinal survey of individuals older than age 50 and their spouses. An ordinary least squares linear regression analysis explores the relationship between financial literacy and several economic and psychosocial variables. After controlling for earnings, level of education, and other socioeconomic variables in this exploratory study, I find that financial satisfaction and religiosity are correlated with financial literacy.

A Longitudinal Assessment of Gifted Students' Learning Using the Integrated Curriculum Model (Icm): Impacts and Perceptions of the William and Mary Language Arts and Science Curriculum

ERIC Educational Resources Information Center

Feng, Annie Xuemei; Van Tassel-Baska, Joyce; Quek, Chwee; Bai, Wenyu; O'Neill, Barbara

2005-01-01

This study examines the effects over time of implementing the William and Mary language arts and science curriculum for gifted learners designed around the Integrated Curriculum Model (ICM) in one suburban school district. It also analyzes stakeholders' perceptions of the effectiveness of the curriculum. Findings suggest that gifted student…

Going and Passing through Community Colleges: Examining the Effectiveness of Project Lead The Way in STEM Pathways

ERIC Educational Resources Information Center

Starobin, Soko S.; Schenk, Tom, Jr.; Laanan, Frankie Santos; Rethwisch, David G.; Moeller, Darin

2013-01-01

Project Lead The Way (PLTW), which aims to create a seamless pathway from secondary education to college and career success in STEM fields, was first implemented in the state of Iowa in 2005. As a part of a statewide, longitudinal research in PLTW, this study explores the effectiveness of PLTW in college persistence by analyzing multiple data…

Why Are Child Poverty Rates Higher in Britain Than in Germany? A Longitudinal Perspective. Working Paper.

ERIC Educational Resources Information Center

Jenkins, Stephen P.; Schluter, Christian

This study analyzed why child poverty rates were so much higher in Great Britain than in Western Germany during the 1990s, focusing on why child poverty exit rates were lower and child poverty entry rates were higher in Great Britain. Researchers used a form of decomposition analysis comparing cross-nationally the prevalence of events that…

The Use of Print Materials in the Internet Age: A Comparative Study of Academic Library Circulation Patterns

ERIC Educational Resources Information Center

Haley, Daniel Joseph

2010-01-01

The circulation records from 1997/98 to 2007/08 for UCLA and from 2000/01 to 2007/08 for Pasadena City College (PCC) were analyzed to examine patterns in the use of print materials during a period of increasingly available online digital information resources. The analysis included examinations of longitudinal circulation patterns broken down by…

Longitudinal Links between Maladaptive Anger Regulation, Peer Problems, and Aggression in Middle Childhood

ERIC Educational Resources Information Center

Rohlf, Helena; Busching, Robert; Krahé, Barbara

2017-01-01

This study examined the prospective links between maladaptive anger regulation and aggressive behavior in middle childhood over a 10-month period, analyzing the mediating influence of peer problems. Participants were 599 elementary school children in Germany, aged 6-10 years at Time 1 (T1) and 7-11 years at Time 2 (T2). Anger regulation at T1 was…

Class, Family, Education and the Process of Status Attainment: A Comparison of American and British Women College Graduates.

ERIC Educational Resources Information Center

Baker, Therese L.

This study of women college graduates in the United States and Great Britain analyzes the effect of social origins and familial factors on educational attainment. The sample consisted of 1,435 American and 1,805 British females who graduated in 1961 and 1960 respectively. Longitudinal data were drawn from the National Opinion Research Center and a…

Progressive attenuation of the longitudinal kinetics in the common carotid artery: preliminary in vivo assessment.

PubMed

Zahnd, Guillaume; Balocco, Simone; Sérusclat, André; Moulin, Philippe; Orkisz, Maciej; Vray, Didier

2015-01-01

Longitudinal kinetics (LOKI) of the arterial wall consists of the shearing motion of the intima-media complex over the adventitia layer in the direction parallel to the blood flow during the cardiac cycle. The aim of this study was to investigate the local variability of LOKI amplitude along the length of the vessel. By use of a previously validated motion-estimation framework, 35 in vivo longitudinal B-mode ultrasound cine loops of healthy common carotid arteries were analyzed. Results indicated that LOKI amplitude is progressively attenuated along the length of the artery, as it is larger in regions located on the proximal side of the image (i.e., toward the heart) and smaller in regions located on the distal side of the image (i.e., toward the head), with an average attenuation coefficient of -2.5 ± 2.0%/mm. Reported for the first time in this study, this phenomenon is likely to be of great importance in improving understanding of atherosclerosis mechanisms, and has the potential to be a novel index of arterial stiffness. Copyright © 2015 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

Mental health, not social support, mediates the forgiveness-alcohol outcome relationship.

PubMed

Webb, Jon R; Robinson, Elizabeth A R; Brower, Kirk J

2011-09-01

Religiousness and spirituality are important to most Americans, and evidence suggests that they may contribute to both addiction and recovery. Forgiveness is a specific dimension of religiousness and spirituality that may enhance recovery, but the mechanism(s) through which it operates is unknown. We hypothesized that higher levels of forgiveness would be associated with higher levels of mental health and social support, which, in turn, would be associated with improved alcohol-related outcomes. Baseline and 6-month longitudinal data from a sample of 149 individuals with alcohol use disorders seeking outpatient substance abuse treatment were analyzed through multiple-mediation statistical techniques. While previous research has shown direct associations among forgiveness, alcohol-related outcomes, mental health, and social support, this study found that the direct associations between forgiveness and alcohol-related outcomes were no longer significant when mental health and social support were analyzed as mediator variables. At baseline, for each alcohol-related outcome measured (alcohol-related problems, percent heavy drinking days, percent days abstinent, and drinks per drinking day), mental health individually played a role in the relationship with both forgiveness of self and forgiveness of others, fully mediating or operating through an indirect-only pathway. For alcohol-related problems only, mental health fully mediated the relationship with forgiveness of self at follow-up and operated through an indirect-only pathway with forgiveness of others longitudinally. Social support and feeling forgiven by God were nonsignificant variables at baseline, follow-up, and longitudinally. (c) 2011 APA, all rights reserved.

Mental Health, not Social Support, Mediates the Forgiveness–Alcohol Outcome Relationship

PubMed Central

Webb, Jon R.; Robinson, Elizabeth A. R.; Brower, Jon R.

2011-01-01

Religiousness and spirituality are important to most Americans and evidence suggests that they may contribute to both addiction and recovery. Forgiveness is a specific dimension of religiousness and spirituality that may enhance recovery, but the mechanism(s) through which it operates is unknown. We hypothesized that higher levels of forgiveness would be associated with higher levels of mental health and social support, which in turn would be associated with improved alcohol-related outcomes. Baseline and 6-month longitudinal data from a sample of 149 individuals with alcohol use disorders seeking outpatient substance abuse treatment were analyzed through multiple-mediation statistical techniques. While previous research has shown direct associations among forgiveness, alcohol-related outcomes, mental health, and social support, this study found that the direct associations between forgiveness and alcohol-related outcomes were no longer significant when mental health and social support were analyzed as mediator variables. At baseline, for each alcohol-related outcome measured (alcohol-related problems, percent heavy drinking days, percent days abstinent, and drinks per drinking day), mental health individually played a role in the relationship with both forgiveness of self and forgiveness of others; fully mediating or operating through an indirect only pathway. For alcohol-related problems only, mental health fully mediated the relationship with forgiveness of self at follow-up and operated through an indirect only pathway with forgiveness of others longitudinally. Social support and feeling forgiven by God were non-significant variables at baseline, follow-up, and longitudinally. PMID:21443306

Some methodological issues in the longitudinal analysis of demographic data.

PubMed

Krishinan, P

1982-12-01

Most demographic data are macro (or aggregate) in nature. Some relevant methodological issues are presented here in a time series study using aggregate data. The micro-macro distinction is relative. Time enters into the micro and macro variables in different ways. A simple micro model of rural-urban migration is given. Method 1 is to assume homogeneity in behavior. Method 2 is a Bayesian estimation. A discusssion of the results follows. Time series models of aggregate data are given. The nature of the model--predictive or explanatory--must be decided on. Explanatory models in longitudinal studies have been developed. Ways to go to the micro level from the macro are discussed. The aggregation-disaggregation problem in demography is not similar to that in econometrics. To understand small populations, separate micro level data have to be collected and analyzed and appropriate models developed. Both types of models have their uses.

At the Frontiers of Modeling Intensive Longitudinal Data: Dynamic Structural Equation Models for the Affective Measurements from the COGITO Study.

PubMed

Hamaker, E L; Asparouhov, T; Brose, A; Schmiedek, F; Muthén, B

2018-04-06

With the growing popularity of intensive longitudinal research, the modeling techniques and software options for such data are also expanding rapidly. Here we use dynamic multilevel modeling, as it is incorporated in the new dynamic structural equation modeling (DSEM) toolbox in Mplus, to analyze the affective data from the COGITO study. These data consist of two samples of over 100 individuals each who were measured for about 100 days. We use composite scores of positive and negative affect and apply a multilevel vector autoregressive model to allow for individual differences in means, autoregressions, and cross-lagged effects. Then we extend the model to include random residual variances and covariance, and finally we investigate whether prior depression affects later depression scores through the random effects of the daily diary measures. We end with discussing several urgent-but mostly unresolved-issues in the area of dynamic multilevel modeling.

Prognostic factors for work ability in women with chronic low back pain consulting primary health care: a 2-year prospective longitudinal cohort study.

PubMed

Nordeman, Lena; Gunnarsson, Ronny; Mannerkorpi, Kaisa

2014-05-01

To investigate prognostic factors for future work ability in women with chronic low back pain (CLBP) consulting primary health care. A 2-year prospective longitudinal cohort study of female patients with CLBP within the primary health care was conducted. Patients were assessed at the first assessment and after 2 years. Prognostic factors for work ability (yes/no) were analyzed by multivariate regression. A total of 130 patients were included at first assessment. After 2 years, 123 patients (95%) were followed up. The 6-minute walk test, depression, and earlier work ability predicted work ability at the 2-year follow-up. A nomogram was constructed to assess the probability of future work ability. The 6-minute walk test, work ability, and depression predicted work ability for women with CLBP after 2 years.

[Early Intervention and Cognitive Development: A Longitudinal Study with Psychologically Stressed Mother-Child-Dyad during Early Childhood].

PubMed

Zwönitzer, Annabel; Ziegenhain, Ute; Bovenschen, Ina; Pillhofer, Melanie; Spangler, Gottfried; Gerlach, Jennifer; Gabler, Sandra; Kindler, Heinz; Fegert, Jörg M; Künster, Anne Katrin

2016-01-01

Early intervention programs aiming at developing parents’ relationship and parenting skills and supporting young families have become increasingly established in Germany throughout the last decade. The present longitudinal study analyzed 53 children and their mothers receiving early intervention due to their psychosocially highly challenging life situations and personal circumstances. The children were examined at birth and at an age of twelve months as well as between ages two and four. The results revealed that the child’s cognitive development could be predicted by both maternal sensitivity and mother’s psychosocial stress. However, the amount, type, and intensity of early intervention did not have any effect on the child’s development. In terms of the effectiveness of early interventions the results implicate that interventions seems to be offered in an unspecific manner and does not contribute to an improvement of the child’s developmental status.

Eating patterns in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil): an exploratory analysis.

PubMed

Cardoso, Letícia de Oliveira; Carvalho, Marilia Sá; Cruz, Oswaldo Gonçalves; Melere, Cristiane; Luft, Vivian Cristine; Molina, Maria Del Carmen Bisi; Faria, Carolina Perim de; Benseñor, Isabela M; Matos, Sheila Maria Alvim; Fonseca, Maria de Jesus Mendes da; Griep, Rosane Harter; Chor, Dóra

2016-01-01

The food consumption of 15,071 public employees was analyzed in six Brazilian cities participating in the baseline for Brazilian Longitudinal Study of Adult Health (ELSA-Brasil, 2008-2010) with the aim of identifying eating patterns and their relationship to socio-demographic variables. Multiple correspondence and cluster analysis were applied. Four patterns were identified, with their respective frequencies: "traditional" (48%); "fruits and vegetables" (25%); "pastry shop" (24%); and "diet/light" (5%) The "traditional" and "pastry shop" patterns were more frequent among men, younger individuals, and those with less schooling. "Fruits and vegetables" and "diet/light" were more frequent in women, older individuals, and those with more schooling. Our findings show the inclusion of new items in the "traditional" pattern and the appearance of the "low sugar/low fat" pattern among the eating habits of Brazilian workers, and signal socio-demographic and regional differences.

The associations between perceived distributive, procedural, and interactional organizational justice, self-rated health and burnout.

PubMed

Liljegren, Mats; Ekberg, Kerstin

2009-01-01

The aim of the present study was to examine the cross-sectional and 2-year longitudinal associations between perceived organizational justice, self-rated health and burnout. The study used questionnaire data from 428 Swedish employment officers and the data was analyzed with Structural Equation Modeling, SEM. Two different models were tested: a global organizational justice model (with and without correlated measurement errors) and a differentiated (distributive, procedural and interactional organizational justice) justice model (with and without correlated measurement errors). The global justice model with autocorrelations had the most satisfactory goodness-of-fit indices. Global justice showed statistically significant (p < 0.01) cross-sectional (0.80 {mle 0.84) and longitudinal positive associations (0.76 mle 0.82) between organizational justice and self-rated health, and significant (p < 0.01) negative associations between organizational justice and burnout (cross-sectional: mle = -0.85, longitudinal -0.83 mle -0.84). The global justice construct showed better goodness-of-fit indices than the threefold justice construct but a differentiated organizational justice concept could give valuable information about health related risk factors: if they are structural (distributive justice), procedural (procedural justice) or inter-personal (interactional justice). The two approaches to study organizational justice should therefore be regarded as complementary rather than exclusive.

Evaluation of Dentin Defect Formation during Retreatment with Hand and Rotary Instruments: A Micro-CT Study.

PubMed

Yilmaz, Ayca; Helvacioglu-Yigit, Dilek; Gur, Cansu; Ersev, Handan; Kiziltas Sendur, Gullu; Avcu, Egemen; Baydemir, Canan; Abbott, Paul Vincent

2017-01-01

The purpose of this study was to compare the incidence and longitudinal propagation of dentin defects after gutta-percha removal with hand and rotary instruments using microcomputed tomography. Twenty mandibular incisors were prepared using the balanced-force technique and scanned in a 19.9  μ m resolution. Following filling with the lateral compaction technique, gutta-percha was removed with ProTaper Universal Retreatment (PTUR) or hand instruments. After rescanning, a total of 24,120 cross-sectional images were analyzed. The numbers, types, and longitudinal length changes of defects were recorded. Defects were observed in 36.90% of the cross sections. A total of 73 defects were comprised of 87.67% craze lines, 2.73% partial cracks, and 9.58% fractures. No significant difference in terms of new defect formation was detected between the retreatment groups. The apical and middle portions of the roots had more dentin defects than the coronal portions. Defects in three roots of the PTUR instrument group increased in length. Under the conditions of this in vitro study, gutta-percha removal seemed to not increase the incidence of dentin defect formation, but the longitudinal defect propagation finding suggests possible cumulative dentinal damage due to additional endodontic procedures. Hand and rotary instrumentation techniques caused similar dentin defect formation during root canal retreatment.

Longitudinal data analysis with non-ignorable missing data.

PubMed

Tseng, Chi-hong; Elashoff, Robert; Li, Ning; Li, Gang

2016-02-01

A common problem in the longitudinal data analysis is the missing data problem. Two types of missing patterns are generally considered in statistical literature: monotone and non-monotone missing data. Nonmonotone missing data occur when study participants intermittently miss scheduled visits, while monotone missing data can be from discontinued participation, loss to follow-up, and mortality. Although many novel statistical approaches have been developed to handle missing data in recent years, few methods are available to provide inferences to handle both types of missing data simultaneously. In this article, a latent random effects model is proposed to analyze longitudinal outcomes with both monotone and non-monotone missingness in the context of missing not at random. Another significant contribution of this article is to propose a new computational algorithm for latent random effects models. To reduce the computational burden of high-dimensional integration problem in latent random effects models, we develop a new computational algorithm that uses a new adaptive quadrature approach in conjunction with the Taylor series approximation for the likelihood function to simplify the E-step computation in the expectation-maximization algorithm. Simulation study is performed and the data from the scleroderma lung study are used to demonstrate the effectiveness of this method. © The Author(s) 2012.

Longitudinal confocal microscopy imaging of solid tumor destruction following adoptive T cell transfer

PubMed Central

Schietinger, Andrea; Arina, Ainhoa; Liu, Rebecca B; Wells, Sam; Huang, Jianhua; Engels, Boris; Bindokas, Vytas; Bartkowiak, Todd; Lee, David; Herrmann, Andreas; Piston, David W; Pittet, Mikael J; Lin, P Charles; Zal, Tomasz; Schreiber, Hans

2013-01-01

A fluorescence-based, high-resolution imaging approach was used to visualize longitudinally the cellular events unfolding during T cell-mediated tumor destruction. The dynamic interplay of T cells, cancer cells, cancer antigen loss variants, and stromal cells—all color-coded in vivo—was analyzed in established, solid tumors that had developed behind windows implanted on the backs of mice. Events could be followed repeatedly within precisely the same tumor region—before, during and after adoptive T cell therapy—thereby enabling for the first time a longitudinal in vivo evaluation of protracted events, an analysis not possible with terminal imaging of surgically exposed tumors. T cell infiltration, stromal interactions, and vessel destruction, as well as the functional consequences thereof, including the elimination of cancer cells and cancer cell variants were studied. Minimal perivascular T cell infiltrates initiated vascular destruction inside the tumor mass eventually leading to macroscopic central tumor necrosis. Prolonged engagement of T cells with tumor antigen-crosspresenting stromal cells correlated with high IFNγ cytokine release and bystander elimination of antigen-negative cancer cells. The high-resolution, longitudinal, in vivo imaging approach described here will help to further a better mechanistic understanding of tumor eradication by T cells and other anti-cancer therapies. PMID:24482750

Investigation of a rotary ultrasonic motor using a longitudinal vibrator and spiral fin rotor.

PubMed

Peng, Taijiang; Wu, Xiaoyu; Liang, Xiong; Shi, Hongyan; Luo, Feng

2015-08-01

A Langevin transducer can provide longitudinal vibration with larger amplitude while also possessing a greater fatigue life than other types of piezoelectric vibrators. A novel rotary Ultrasonic Motor (USM) was proposed based on the use of a longitudinal transducer (acting as the stator) and a spiral fin rotor: the front cover of the Langevin transducer was designed as a double-layer cup-shaped structure, with the rotor sustained by the inner-layer, and the bearing cover fixed to the outer-layer; the rotor consisted of a shaft and spiral fins which acted as the elastic coupler. It is different from a traditional traveling USM, because the stator provides longitudinal vibration and the rotor generates the elliptical motion. This paper analyzed the motion locus equation of the fin contact points. Additionally, a theoretical analysis was performed in regards to the mechanism and the motor's rotor motion characteristics, which demonstrates the relationships among the motor's driving force, the torque, the revolution speed, and the motor structure parameters. A motor prototype has been manufactured and surveyed to demonstrate the motor performance. The relationships between the amplitude and the preload on the rotor, the free revolution speed, and the torque of the motor have also been studied. Copyright © 2015 Elsevier B.V. All rights reserved.

An evaluation of fruit and vegetable consumption and cigarette smoking among youth.

PubMed

Haibach, Jeffrey P; Homish, Gregory G; Collins, R Lorraine; Ambrosone, Christine B; Giovino, Gary A

2015-06-01

Research across the past 4 decades has supported a cross-sectional association between adult cigarette smoking and lower fruit and vegetable consumption (FVC), and emerging research suggests higher FVC may predict cessation. Among youth, findings are limited to a few cross-sectional studies with somewhat mixed results. Here we evaluated the FVC-smoking association among youth both cross-sectionally and longitudinally. We analyzed data from a subsample of the National Longitudinal Survey of Youth 1979: Child and Young Adult. The subsample included adolescents aged 14-18 years at baseline in the year 2004. Multivariable cross-sectional analyses assessed whether baseline FVC was associated with smoking frequency among ever-smokers (n = 578). Longitudinally, the study assessed whether baseline FVC predicted smoking progression among baseline never-smokers who tried a cigarette by 4-year follow-up (n = 388). Multivariable regression models adjusted for age, gender, race/ethnicity, parental education, and health behavior orientation. Cross-sectionally, youth who consumed fruit ≥2 times per day were 53% less likely (RR = 0.47; p < .05) than those who typically did not consume fruit to be in a higher smoking frequency category. Longitudinally, the fruit consumption and smoking association was not significant (RR = 0.61; p = .282). There were no significant associations observed between vegetable consumption and smoking. Fruit consumption, but not vegetable consumption, was inversely associated with smoking frequency cross-sectionally but not longitudinally. Further research is needed to provide information on the consistency of the FVC-smoking relationship among youth and may help to elucidate possible explanatory mechanisms. © The Author 2014. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Determinants of response in a longitudinal health study following the firework-disaster in Enschede, The Netherlands.

PubMed

Dijkema, Marieke B A; Grievink, Linda; Stellato, Rebecca K; Roorda, Jan; van der Velden, Peter G

2005-01-01

Very few longitudinal health studies after disasters published data on the determinants of loss to follow up. However, these determinants provide important information for future disaster studies to improve their response and reduce selection bias. For this purpose we analyzed the data of a longitudinal health survey which was performed among residents and emergency workers, at 3 weeks (n = 3662) and at 18 months (n = 2769) after a major firework disaster in The Netherlands (Enschede, May 13, 2000). The response was lower among immigrants (54%) than among native Dutch (81%). Severe damage to the house due to the disaster (OR: 1.8; 95% CI: 1.1-3.0) and being involved as an emergency workers (OR: 2.1; 95% CI: 1.2-3.4) were associated with higher response among native Dutch, while this was not the case among immigrants. Non-western immigrants with health problems in the first study were more likely to participate in the second study (for example physical symptoms OR: 2.5: 95% CI: 1.4-4.4), while the native Dutch with these symptoms were less likely to participate (OR: 0.7; 95% CI: 0.5-0.9). In conclusion, disaster-related characteristics were associated with higher response in native Dutch. Health problems were associated with higher response among non-western immigrants and with lower response among the native Dutch.

A Measurement of the Average Longitudinal Development Profile of Cosmic Ray Air Showers from 1017.5eV to 1020eV by HiRes-II

NASA Astrophysics Data System (ADS)

Hughes, G.

Ultra High Energy Cosmic Rays (UHECRs) have an energy many times greater than that of particles accelerated in colliders. The Extended Air Showers (EAS) resulting from their interaction in the atmosphere give us the opportunity to study not only Cosmic Rays but also these extremely energetic cascades. A method to calculate the Average Longitudinal Shower profile has been applied to the High Resolution Fly's Eye Detector (HiRes) data. A complete detector simulation was used to throw CORSIKA (QGSJET) showers which are then analyzed using the same technique. The main features of the average showers are compared to the Monte Carlo as a function of energy. Systematic errors in the reconstruction of the profile are considered.

Pattern of structural brain changes in social anxiety disorder after cognitive behavioral group therapy: a longitudinal multimodal MRI study.

PubMed

Steiger, V R; Brühl, A B; Weidt, S; Delsignore, A; Rufer, M; Jäncke, L; Herwig, U; Hänggi, J

2017-08-01

Social anxiety disorder (SAD) is characterized by fears of social and performance situations. Cognitive behavioral group therapy (CBGT) has in general positive effects on symptoms, distress and avoidance in SAD. Prior studies found increased cortical volumes and decreased fractional anisotropy (FA) in SAD compared with healthy controls (HCs). Thirty-three participants diagnosed with SAD attended in a 10-week CBGT and were scanned before and after therapy. We applied three neuroimaging methods-surface-based morphometry, diffusion tensor imaging and network-based statistics-each with specific longitudinal processing protocols, to investigate CBGT-induced structural brain alterations of the gray and white matter (WM). Surface-based morphometry revealed a significant cortical volume reduction (pre- to post-treatment) in the left inferior parietal cortex, as well as a positive partial correlation between treatment success (indexed by reductions in Liebowitz Social Anxiety Scale) and reductions in cortical volume in bilateral dorsomedial prefrontal cortex. Diffusion tensor imaging analysis revealed a significant increase in FA in bilateral uncinate fasciculus and right inferior longitudinal fasciculus. Network-based statistics revealed a significant increase of structural connectivity in a frontolimbic network. No partial correlations with treatment success have been found in WM analyses. For, we believe, the first time, we present a distinctive pattern of longitudinal structural brain changes after CBGT measured with three established magnetic resonance imaging analyzing techniques. Our findings are in line with previous cross-sectional, unimodal SAD studies and extent them by highlighting anatomical brain alterations that point toward the level of HCs in parallel with a reduction in SAD symptomatology.

medplot: a web application for dynamic summary and analysis of longitudinal medical data based on R.

PubMed

Ahlin, Črt; Stupica, Daša; Strle, Franc; Lusa, Lara

2015-01-01

In biomedical studies the patients are often evaluated numerous times and a large number of variables are recorded at each time-point. Data entry and manipulation of longitudinal data can be performed using spreadsheet programs, which usually include some data plotting and analysis capabilities and are straightforward to use, but are not designed for the analyses of complex longitudinal data. Specialized statistical software offers more flexibility and capabilities, but first time users with biomedical background often find its use difficult. We developed medplot, an interactive web application that simplifies the exploration and analysis of longitudinal data. The application can be used to summarize, visualize and analyze data by researchers that are not familiar with statistical programs and whose knowledge of statistics is limited. The summary tools produce publication-ready tables and graphs. The analysis tools include features that are seldom available in spreadsheet software, such as correction for multiple testing, repeated measurement analyses and flexible non-linear modeling of the association of the numerical variables with the outcome. medplot is freely available and open source, it has an intuitive graphical user interface (GUI), it is accessible via the Internet and can be used within a web browser, without the need for installing and maintaining programs locally on the user's computer. This paper describes the application and gives detailed examples describing how to use the application on real data from a clinical study including patients with early Lyme borreliosis.

Longitudinal Psychosocial Adjustment of Women to Human Papillomavirus Infection.

PubMed

Hsu, Yu-Yun; Wang, Wei-Ming; Fetzer, Susan Jane; Cheng, Ya-Min; Hsu, Keng-Fu

2018-05-29

The aim of this study was to examine the psychosocial adjustment trajectory, focusing on psychological distress, sexual relationships and health care information, as well as factors which have an impact on adjustment on receiving a positive diagnosis of human papillomavirus infection. Human papillomavirus is a common sexually transmitted infection in females. To date, knowledge of the longitudinal psychosocial response to the diagnosis of human papillomavirus is limited. A prospective longitudinal design was conducted with a convenience sample. Women aged 20-65 years old were followed at one, 6 and 12 months after a diagnosis of HPV. Participants completed measures of initial emotional distress and followed-up psychosocial adjustment. A mixed-effects model was applied to analyze the longitudinal changes in psychosocial adjustment. Seventy human papillomavirus positive women participated in the study with nearly 20% of the women reporting emotional distress during their first visit. Mixed-effects model analyses showed that a trajectory of psychosocial adjustment in health care orientation, sexual relationship and psychosocial distress occur from one to 6 months after HPV diagnosis. However, a declining trend from 6-12 months was significant in health care orientation. Initial emotional distress was associated with changes in psychological adjustment. Psychosocial adjustment to human papillomavirus was worse at one month compared with 6 and 12 months after diagnosis. Healthcare providers should offer health information and psychosocial support to women according to their disease progression. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Patient-Related Benefits for Adults with Cochlear Implantation: A Multicultural Longitudinal Observational Study.

PubMed

Lenarz, Thomas; Muller, Lida; Czerniejewska-Wolska, Hanna; Vallés Varela, Hector; Orús Dotú, César; Durko, Marcin; Huarte Irujo, Alicia; Piszczatowski, Bartosz; Zadrożniak, Marek; Irwin, Colin; Graham, Petra L; Wyss, Josie

2017-01-01

To assess subjectively perceived, real-world benefits longitudinally for unilateral cochlear implant (CI) recipients in a multinational population treated routinely. To identify possible predictors of self-reported benefits. This was a prospective, multicenter, repeated-measures study. Self-assessment of performance at preimplantation and postimplantation at 1, 2, and 3 years using standardized, validated, local language versions of the Speech, Spatial, and Qualities of Hearing Scale (SSQ), and the Health Utilities Index Mark 3 (HUI3) was performed. Outcomes were analyzed using a longitudinal mixed-effects model incorporating country effect. Patient demographics were explored for associations with change over time. Two hundred ninety-one routinely treated, unilateral CI recipients, aged 13-81 years, from 9 clinics across 4 countries. Highly significant improvements were observed for all outcome measures (p < 0.0001). Postimplantation, mean outcome scores remained stable beyond 1 year, with notable individual variability. A significant association for one or more outcomes with preimplantation contralateral hearing aid use, telephone use, age at implantation, implantation side, preimplantation comorbidities, dizziness, and tinnitus was observed (p < 0.004). Longitudinal benefits of CI treatment can be measured using clinically standardized self-assessment tools to provide a holistic view of patient-related benefits in routine clinical practice for aggregated data from multinational populations. Self-reported outcomes can provide medical-based evidence regarding CI treatment to support decision-making by health service providers. © 2017 The Author(s) Published by S. Karger AG, Basel.

Stabilized and tunable single-longitudinal-mode erbium fiber laser employing ytterbium-doped fiber based interference filter

NASA Astrophysics Data System (ADS)

Yeh, Chien-Hung; Tsai, Ning; Zhuang, Yuan-Hong; Chow, Chi-Wai; Chen, Jing-Heng

2017-02-01

In this demonstration, to achieve stabilized and wavelength-selectable single-longitudinal-mode (SLM) erbium-doped fiber (EDF) laser, a short length of ytterbium-doped fiber (YDF) is utilized to serve as a spatial multi-mode interference (MMI) inside a fiber cavity for suppressing multi-longitudinal-mode (MLM) significantly. In the measurement, the output powers and optical signal to noise ratios (OSNRs) of proposed EDF ring laser are measured between -9.85 and -5.71 dBm; and 38.03 and 47.95 dB, respectively, in the tuning range of 1530.0-1560.0 nm. In addition, the output SLM and stability performance are also analyzed and discussed experimentally.

The reciprocal relationships among parents' expectations, adolescents' expectations, and adolescents' achievement: a two-wave longitudinal analysis of the NELS data.

PubMed

Zhang, Yanyan; Haddad, Eileen; Torres, Bernadeth; Chen, Chuansheng

2011-04-01

Previous research has consistently demonstrated the importance of parents' expectations and adolescents' expectations on adolescents' academic achievement. Less is known, however, about the reciprocal relationships among these constructs. To address this issue, we analyzed two waves of data from the National Education Longitudinal Study of 1988 (NELS:88) using longitudinal cross-lagged path models. The sample consisted of 14,376 students (51.1% females; 6.5% Asian, 11.1% Hispanic, 9.2% African American, and 73.2% White). Results indicated that there was a reciprocal relationship between parents' expectations and adolescents' expectations (i.e., they had mutual influence on each other). Moreover, there was a reciprocal relationship between expectations (both parents' and adolescents') and adolescents' academic achievement. Multiple-group analyses of gender and ethnicity revealed that the effects of parents' expectations on students' expectations were stronger among males than among females. With respect to ethnic differences, the effects of adolescents' expectations were weakest on parents' expectations among African Americans as compared to the other ethnic groups (i.e., Asian, Hispanic and White). Implications of these findings are discussed.

A generalized partially linear mean-covariance regression model for longitudinal proportional data, with applications to the analysis of quality of life data from cancer clinical trials.

PubMed

Zheng, Xueying; Qin, Guoyou; Tu, Dongsheng

2017-05-30

Motivated by the analysis of quality of life data from a clinical trial on early breast cancer, we propose in this paper a generalized partially linear mean-covariance regression model for longitudinal proportional data, which are bounded in a closed interval. Cholesky decomposition of the covariance matrix for within-subject responses and generalized estimation equations are used to estimate unknown parameters and the nonlinear function in the model. Simulation studies are performed to evaluate the performance of the proposed estimation procedures. Our new model is also applied to analyze the data from the cancer clinical trial that motivated this research. In comparison with available models in the literature, the proposed model does not require specific parametric assumptions on the density function of the longitudinal responses and the probability function of the boundary values and can capture dynamic changes of time or other interested variables on both mean and covariance of the correlated proportional responses. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Piagetian Perspective in Draw-a-House Tree Task: A Longitudinal Study of the Drawings of Rural Children in the State of Nebraska, U.S.A.

ERIC Educational Resources Information Center

Kalyan-Masih, Violet

Children's drawings of "a house with a tree behind it" were analyzed for (1) developmental changes in graphic representation over a 3-year period; (2) relationship with Piagetian tasks (the Nebraska Wisconsin Cognitive Assessment Battery of the NC-124), Peabody IQ, and WISC-R; and (3) correspondence with the Luquet-Piaget sequence of…

Street Ball, Swim Team and the Sour Cream Machine: A Cluster Analysis of out of School Time Participation Portfolios

ERIC Educational Resources Information Center

Nelson, Ingrid Ann; Gastic, Billie

2009-01-01

Adolescents spend only a fraction of their waking hours in school and what they do with the rest of their time varies dramatically. Despite this, research on out-of-school time has largely focused on structured programming. The authors analyzed data from the Educational Longitudinal Study of 2002 (ELS:2002) to examine the out-of-school time…

The Effects of Large Wood on Stream Channel Morphology on Three Low-Gradient Stream Reaches in the Coastal Redwood Region

Treesearch

Scott Carroll; E. George Robison

2007-01-01

Several studies have shown that large wood has a prominent role in habitat quality, however there is little research on the role of wood on pool characteristics and other habitat components in low gradient streams (channel slopes less than one percent). Longitudinal profiles are used to analyze general residual pool characteristics of three approximately 1000-meter...

Characterize Respiratory Pathogens Endemic to Pakistan

DTIC Science & Technology

2017-10-25

Impact of respiratory illnesses during pregnancy on newborn’s weight - A community based longitudinal study at an urban slum in Pakistan. Asad Ali1...Although maternal health is widely believed to impact the birth weight of the baby, the exact factors during pregnancy that influence the birth... pregnancies have concluded as live deliveries, 12 as still births and 31 as spontaneous abortions. We analyzed the data of 243 pregnant     5

Sources of Variability in Language Development of Children with Cochlear Implants: Age at Implantation, Parental Language, and Early Features of Children's Language Construction

ERIC Educational Resources Information Center

Szagun, Gisela; Schramm, Satyam A.

2016-01-01

The aim of the present study was to analyze the relative influence of age at implantation, parental expansions, and child language internal factors on grammatical progress in children with cochlear implants (CI). Data analyses used two longitudinal corpora of spontaneous speech samples, one with twenty-two and one with twenty-six children,…

Student Workers in High School and Beyond: The Effects of Part-Time Employment on Participation in Education, Training and Work.

ERIC Educational Resources Information Center

Vickers, Margaret; Lamb, Stephen; Hinkley, John

Data on the Y95 cohort (first interviewed in 1995 when in Year 9) of the Longitudinal Surveys of Australian Youth were analyzed to identify the effects of student employment on participation and attrition in secondary school and tertiary study and on young people's activities after secondary school. Working between 1 and 5 hours during Year 9 of…

Mathematical modeling of pulsatile flow of non-Newtonian fluid in stenosed arteries

NASA Astrophysics Data System (ADS)

Sankar, D. S.; Lee, Usik

2009-07-01

The pulsatile flow of blood through mild stenosed artery is studied. The effects of pulsatility, stenosis and non-Newtonian behavior of blood, treating the blood as Herschel-Bulkley fluid, are simultaneously considered. A perturbation method is used to analyze the flow. The expressions for the shear stress, velocity, flow rate, wall shear stress, longitudinal impedance and the plug core radius have been obtained. The variations of these flow quantities with different parameters of the fluid have been analyzed. It is found that, the plug core radius, pressure drop and wall shear stress increase with the increase of yield stress or the stenosis height. The velocity and the wall shear stress increase considerably with the increase in the amplitude of the pressure drop. It is clear that for a given value of stenosis height and for the increasing values of the stenosis shape parameter from 3 to 6, there is a sharp increase in the impedance of the flow and also the plots are skewed to the right-hand side. It is observed that the estimates of the increase in the longitudinal impedance increase with the increase of the axial distance or with the increase of the stenosis height. The present study also brings out the effects of asymmetric of the stenosis on the flow quantities.

Quantitative Amyloid Imaging in Autosomal Dominant Alzheimer's Disease: Results from the DIAN Study Group.

PubMed

Su, Yi; Blazey, Tyler M; Owen, Christopher J; Christensen, Jon J; Friedrichsen, Karl; Joseph-Mathurin, Nelly; Wang, Qing; Hornbeck, Russ C; Ances, Beau M; Snyder, Abraham Z; Cash, Lisa A; Koeppe, Robert A; Klunk, William E; Galasko, Douglas; Brickman, Adam M; McDade, Eric; Ringman, John M; Thompson, Paul M; Saykin, Andrew J; Ghetti, Bernardino; Sperling, Reisa A; Johnson, Keith A; Salloway, Stephen P; Schofield, Peter R; Masters, Colin L; Villemagne, Victor L; Fox, Nick C; Förster, Stefan; Chen, Kewei; Reiman, Eric M; Xiong, Chengjie; Marcus, Daniel S; Weiner, Michael W; Morris, John C; Bateman, Randall J; Benzinger, Tammie L S

2016-01-01

Amyloid imaging plays an important role in the research and diagnosis of dementing disorders. Substantial variation in quantitative methods to measure brain amyloid burden exists in the field. The aim of this work is to investigate the impact of methodological variations to the quantification of amyloid burden using data from the Dominantly Inherited Alzheimer's Network (DIAN), an autosomal dominant Alzheimer's disease population. Cross-sectional and longitudinal [11C]-Pittsburgh Compound B (PiB) PET imaging data from the DIAN study were analyzed. Four candidate reference regions were investigated for estimation of brain amyloid burden. A regional spread function based technique was also investigated for the correction of partial volume effects. Cerebellar cortex, brain-stem, and white matter regions all had stable tracer retention during the course of disease. Partial volume correction consistently improves sensitivity to group differences and longitudinal changes over time. White matter referencing improved statistical power in the detecting longitudinal changes in relative tracer retention; however, the reason for this improvement is unclear and requires further investigation. Full dynamic acquisition and kinetic modeling improved statistical power although it may add cost and time. Several technical variations to amyloid burden quantification were examined in this study. Partial volume correction emerged as the strategy that most consistently improved statistical power for the detection of both longitudinal changes and across-group differences. For the autosomal dominant Alzheimer's disease population with PiB imaging, utilizing brainstem as a reference region with partial volume correction may be optimal for current interventional trials. Further investigation of technical issues in quantitative amyloid imaging in different study populations using different amyloid imaging tracers is warranted.

Quantitative Amyloid Imaging in Autosomal Dominant Alzheimer’s Disease: Results from the DIAN Study Group

PubMed Central

Su, Yi; Blazey, Tyler M.; Owen, Christopher J.; Christensen, Jon J.; Friedrichsen, Karl; Joseph-Mathurin, Nelly; Wang, Qing; Hornbeck, Russ C.; Ances, Beau M.; Snyder, Abraham Z.; Cash, Lisa A.; Koeppe, Robert A.; Klunk, William E.; Galasko, Douglas; Brickman, Adam M.; McDade, Eric; Ringman, John M.; Thompson, Paul M.; Saykin, Andrew J.; Ghetti, Bernardino; Sperling, Reisa A.; Johnson, Keith A.; Salloway, Stephen P.; Schofield, Peter R.; Masters, Colin L.; Villemagne, Victor L.; Fox, Nick C.; Förster, Stefan; Chen, Kewei; Reiman, Eric M.; Xiong, Chengjie; Marcus, Daniel S.; Weiner, Michael W.; Morris, John C.; Bateman, Randall J.; Benzinger, Tammie L. S.

2016-01-01

Amyloid imaging plays an important role in the research and diagnosis of dementing disorders. Substantial variation in quantitative methods to measure brain amyloid burden exists in the field. The aim of this work is to investigate the impact of methodological variations to the quantification of amyloid burden using data from the Dominantly Inherited Alzheimer’s Network (DIAN), an autosomal dominant Alzheimer’s disease population. Cross-sectional and longitudinal [11C]-Pittsburgh Compound B (PiB) PET imaging data from the DIAN study were analyzed. Four candidate reference regions were investigated for estimation of brain amyloid burden. A regional spread function based technique was also investigated for the correction of partial volume effects. Cerebellar cortex, brain-stem, and white matter regions all had stable tracer retention during the course of disease. Partial volume correction consistently improves sensitivity to group differences and longitudinal changes over time. White matter referencing improved statistical power in the detecting longitudinal changes in relative tracer retention; however, the reason for this improvement is unclear and requires further investigation. Full dynamic acquisition and kinetic modeling improved statistical power although it may add cost and time. Several technical variations to amyloid burden quantification were examined in this study. Partial volume correction emerged as the strategy that most consistently improved statistical power for the detection of both longitudinal changes and across-group differences. For the autosomal dominant Alzheimer’s disease population with PiB imaging, utilizing brainstem as a reference region with partial volume correction may be optimal for current interventional trials. Further investigation of technical issues in quantitative amyloid imaging in different study populations using different amyloid imaging tracers is warranted. PMID:27010959

Post and during event effect of cell phone talking and texting on driving performance--a driving simulator study.

PubMed

Thapa, Raju; Codjoe, Julius; Ishak, Sherif; McCarter, Kevin S

2015-01-01

A number of studies have been done in the field of driver distraction, specifically on the use of cell phone for either conversation or texting while driving. Researchers have focused on the driving performance of drivers when they were actually engaged in the task; that is, during the texting or phone conversation event. However, it is still unknown whether the impact of cell phone usages ceases immediately after the end of task. The primary objective of this article is to analyze the post-event effect of cell phone usage (texting and conversation) in order to verify whether the distracting effect lingers after the actual event has ceased. This study utilizes a driving simulator study of 36 participants to test whether a significant decrease in driver performance occurs during cell phone usage and after usage. Surrogate measures used to represent lateral and longitudinal control of the vehicle were standard deviation (SD) of lane position and mean velocity, respectively. RESULTS suggest that there was no significant decrease in driver performance (both lateral and longitudinal control) during and after the cell phone conversation. For the texting event, there were significant decreases in driver performance in both the longitudinal and lateral control of the vehicle during the actual texting task. The diminished longitudinal control ceased immediately after the texting event but the diminished lateral control lingered for an average of 3.38 s. The number of text messages exchanged did not affect the magnitude or duration of the diminished lateral control. The result indicates that the distraction and subsequent elevated crash risk of texting while driving linger even after the texting event has ceased. This finding has safety and policy implications in reducing distracted driving.

Analysis of the longitudinal space charge impedance of a round uniform beam inside parallel plates and rectangular chambers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, L.; Li, Y.

2015-02-03

This paper analyzes the longitudinal space charge impedances of a round uniform beam inside a rectangular and parallel plate chambers using the image charge method. This analysis is valid for arbitrary wavelengths, and the calculations converge rapidly. The research shows that only a few of the image beams are needed to obtain a relative error less than 0.1%. The beam offset effect is also discussed in the analysis.

Comparing identified and statistically significant lipids and polar metabolites in 15-year old serum and dried blood spot samples for longitudinal studies: Comparing lipids and metabolites in serum and DBS samples

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kyle, Jennifer E.; Casey, Cameron P.; Stratton, Kelly G.

The use of dried blood spots (DBS) has many advantages over traditional plasma and serum samples such as smaller blood volume required, storage at room temperature, and ability for sampling in remote locations. However, understanding the robustness of different analytes in DBS samples is essential, especially in older samples collected for longitudinal studies. Here we analyzed DBS samples collected in 2000-2001 and stored at room temperature and compared them to matched serum samples stored at -80°C to determine if they could be effectively used as specific time points in a longitudinal study following metabolic disease. Four hundred small molecules weremore » identified in both the serum and DBS samples using gas chromatograph-mass spectrometry (GC-MS), liquid chromatography-MS (LC-MS) and LC-ion mobility spectrometry-MS (LC-IMS-MS). The identified polar metabolites overlapped well between the sample types, though only one statistically significant polar metabolite in a case-control study was conserved, indicating degradation occurs in the DBS samples affecting quantitation. Differences in the lipid identifications indicated that some oxidation occurs in the DBS samples. However, thirty-six statistically significant lipids correlated in both sample types indicating that lipid quantitation was more stable across the sample types.« less

Regulatory gene expression patterns reveal transverse and longitudinal subdivisions of the embryonic zebrafish forebrain.

PubMed

Hauptmann, G; Gerster, T

2000-03-01

To shed light on the organization of the rostral embryonic brain of a lower vertebrate, we have directly compared the expression patterns of dlx, fgf, hh, hlx, otx, pax, POU, winged helix and wnt gene family members in the fore- and midbrain of the zebrafish. We show that the analyzed genes are expressed in distinct transverse and longitudinal domains and share expression boundaries at stereotypic positions within the fore- and midbrain. Some of these shared expression boundaries coincide with morphological landmarks like the pathways of primary axon tracts. We identified a series of eight transverse diencephalic domains suggestive of neuromeric subdivisions within the rostral brain. In addition, we identified four molecularly distinct longitudinal subdivisions and provide evidence for a strong bending of the longitudinal rostral brain axis at the cephalic flexure. Our data suggest a strong conservation of early forebrain organization between lower and higher vertebrates.

Longitudinal On-Column Thermal Modulation for Comprehensive Two-Dimensional Liquid Chromatography.

PubMed

Creese, Mari E; Creese, Mathew J; Foley, Joe P; Cortes, Hernan J; Hilder, Emily F; Shellie, Robert A; Breadmore, Michael C

2017-01-17

Longitudinal on-column thermal modulation for comprehensive two-dimensional liquid chromatography is introduced. Modulation optimization involved a systematic investigation of heat transfer, analyte retention, and migration velocity at a range of temperatures. Longitudinal on-column thermal modulation was realized using a set of alkylphenones and compared to a conventional valve-modulator employing sample loops. The thermal modulator showed a reduced modulation-induced pressure impact than valve modulation, resulting in reduced baseline perturbation by a factor of 6; yielding a 6-14-fold improvement in signal-to-noise. A red wine sample was analyzed to demonstrate the potential of the longitudinal on-column thermal modulator for separation of a complex sample. Discrete peaks in the second dimension using the thermal modulator were 30-55% narrower than with the valve modulator. The results shown herein demonstrate the benefits of an active focusing modulator, such as reduced detection limits and increased total peak capacity.

Exposing the Backstage: Critical Reflections on a Longitudinal Qualitative Study of Residents’ Care Networks in Assisted Living

PubMed Central

Kemp, Candace L.; Ball, Mary M.; Morgan, Jennifer Craft; Doyle, Patrick J.; Burgess, Elisabeth O.; Dillard, Joy A.; Barmon, Christina E.; Fitzroy, Andrea F.; Helmly, Victoria E.; Avent, Elizabeth S.; Perkins, Molly M.

2018-01-01

In this article, we analyze the research experiences associated with a longitudinal qualitative study of residents’ care networks in assisted living. Using data from researcher meetings, field notes, and memos, we critically examine our design and decision making and accompanying methodological implications. We focus on one complete wave of data collection involving 28 residents and 114 care network members in four diverse settings followed for 2 years. We identify study features that make our research innovative, but that also represent significant challenges. They include the focus and topic; settings and participants; scope and design complexity; nature, modes, frequency, and duration of data collection; and analytic approach. Each feature has methodological implications, including benefits and challenges pertaining to recruitment, retention, data collection, quality, and management, research team work, researcher roles, ethics, and dissemination. Our analysis demonstrates the value of our approach and of reflecting on and sharing methodological processes for cumulative knowledge building. PMID:27651072

Customer orientation among employees in public administration: a transnational, longitudinal study.

PubMed

Korunka, Christian; Scharitzer, Dieter; Carayon, Pascale; Hoonakker, Peter; Sonnek, Angelika; Sainfort, Francois

2007-05-01

The relation between ergonomic principles and quality management initiatives, both, in the private and public sector, has received increasing attention in the recent years. Customer orientation among employees is not only an important quality principle, but also an essential prerequisite for customer satisfaction, especially in service organizations. In this context, the objective of introducing new public management (NPM) in public-service organizations is to increase customer orientation among employees who are at the forefront of service providing. In this study, we developed a short scale to measure perceived customer orientation. In two separate longitudinal studies carried out in Austria and the US, we analyzed changes in customer orientation resulting from the introduction of NPM. In both organizations, we observed a significant increase in customer orientation. Perceived customer orientation was related to job characteristics, organizational characteristics and employee quality of working life. Creating positive influences on these characteristics within the framework of an organizational change process has positive effects on employee customer orientation.

A Neonatal Resuscitation Curriculum in Malawi, Africa: Did It Change In-Hospital Mortality?

PubMed Central

Hole, Michael K.; Olmsted, Keely; Kiromera, Athanase; Chamberlain, Lisa

2012-01-01

Objective. The WHO estimates that 99% of the 3.8 million neonatal deaths occur in developing countries. Neonatal resuscitation training was implemented in Namitete, Malawi. The study's objective was to evaluate the training's impact on hospital staff and neonatal mortality rates. Study Design. Pre-/postcurricular surveys of trainee attitude, knowledge, and skills were analyzed. An observational, longitudinal study of secondary data assessed neonatal mortality. Result. All trainees' (n = 18) outcomes improved, (P = 0.02). Neonatal mortality did not change. There were 3449 births preintervention, 3515 postintervention. Neonatal mortality was 20.9 deaths per 1000 live births preintervention and 21.9/1000 postintervention, (P = 0.86). Conclusion. Short-term pre-/postintervention evaluations frequently reveal positive results, as ours did. Short-term pre- and postintervention evaluations should be interpreted cautiously. Whenever possible, clinical outcomes such as in-hospital mortality should be additionally assessed. More rigorous evaluation strategies should be applied to training programs requiring longitudinal relationships with international community partners. PMID:22164184

Exposing the Backstage: Critical Reflections on a Longitudinal Qualitative Study of Residents' Care Networks in Assisted Living.

PubMed

Kemp, Candace L; Ball, Mary M; Morgan, Jennifer Craft; Doyle, Patrick J; Burgess, Elisabeth O; Dillard, Joy A; Barmon, Christina E; Fitzroy, Andrea F; Helmly, Victoria E; Avent, Elizabeth S; Perkins, Molly M

2017-07-01

In this article, we analyze the research experiences associated with a longitudinal qualitative study of residents' care networks in assisted living. Using data from researcher meetings, field notes, and memos, we critically examine our design and decision making and accompanying methodological implications. We focus on one complete wave of data collection involving 28 residents and 114 care network members in four diverse settings followed for 2 years. We identify study features that make our research innovative, but that also represent significant challenges. They include the focus and topic; settings and participants; scope and design complexity; nature, modes, frequency, and duration of data collection; and analytic approach. Each feature has methodological implications, including benefits and challenges pertaining to recruitment, retention, data collection, quality, and management, research team work, researcher roles, ethics, and dissemination. Our analysis demonstrates the value of our approach and of reflecting on and sharing methodological processes for cumulative knowledge building.

Relationship between Mobile Phone Addiction and the Incidence of Poor and Short Sleep among Korean Adolescents: a Longitudinal Study of the Korean Children & Youth Panel Survey.

PubMed

Lee, Joo Eun; Jang, Sung In; Ju, Yeong Jun; Kim, Woorim; Lee, Hyo Jung; Park, Eun Cheol

2017-07-01

Three of ten teenagers in Korea are addicted to mobile phones. The aim of this study was to examine the relationship between mobile phone addiction and the incidence of poor sleep quality and short sleep duration in adolescents. We used longitudinal data from the Korean Children & Youth Panel Survey conducted by the National Youth Policy Institute in Korea (2011-2013). A total of 1,125 students at baseline were included in this study after excluding those who already had poor sleep quality or short sleep duration in the previous year. A generalized estimating equation was used to analyze the data. High mobile phone addiction (mobile phone addiction score > 20) increased the risk of poor sleep quality but not short sleep duration. We suggest that consistent monitoring and effective intervention programs are required to prevent mobile phone addiction and improve adolescents' sleep quality. © 2017 The Korean Academy of Medical Sciences.

Relationship between Mobile Phone Addiction and the Incidence of Poor and Short Sleep among Korean Adolescents: a Longitudinal Study of the Korean Children & Youth Panel Survey

PubMed Central

2017-01-01

Three of ten teenagers in Korea are addicted to mobile phones. The aim of this study was to examine the relationship between mobile phone addiction and the incidence of poor sleep quality and short sleep duration in adolescents. We used longitudinal data from the Korean Children & Youth Panel Survey conducted by the National Youth Policy Institute in Korea (2011–2013). A total of 1,125 students at baseline were included in this study after excluding those who already had poor sleep quality or short sleep duration in the previous year. A generalized estimating equation was used to analyze the data. High mobile phone addiction (mobile phone addiction score > 20) increased the risk of poor sleep quality but not short sleep duration. We suggest that consistent monitoring and effective intervention programs are required to prevent mobile phone addiction and improve adolescents' sleep quality. PMID:28581275

Dietary Selenium Intake and Subclinical Hypothyroidism: A Cross-Sectional Analysis of the ELSA-Brasil Study.

PubMed

Andrade, Gustavo R G; Gorgulho, Bartira; Lotufo, Paulo A; Bensenor, Isabela M; Marchioni, Dirce M

2018-05-30

Selenium (Se) participates in several enzymatic reactions necessary for regulating the homeostasis of thyroid hormones. We aimed to analyze the association between dietary Se intake and subclinical hypothyroidism. Baseline data from the Longitudinal Study of Adult Health (Estudo Longitudinal de Saúde do Adulto-ELSA-Brasil) in Brazil were analyzed, with a final sample size of 14,283 employees of both sexes aged 35⁻74 years. Dietary data was collected using a previously validated food frequency questionnaire. Subclinical hypothyroidism was categorized as thyroid-stimulating hormone levels of >4.0 IU/mL and free prohormone thyroxine levels within normal limits, without administering drugs for thyroid disease. A multiple logistic regression model was used to assess the relationship between the presence of subclinical hypothyroidism and tertiles of Se consumption. The prevalence of subclinical hypothyroidism in the study sample was 5.4% (95% confidence interval [CI], 3.8⁻7.0%). Compared with the first tertile of Se intake, the second (odds ratio [OR], 0.79; 95% CI, 0.65⁻0.96%) and third (OR, 0.72; 95% CI, 0.58⁻0.90%) tertiles were inversely associated with subclinical hypothyroidism, however further research is needed to confirm the involvement of Se in subclinical hypothyroidism using more accurate methodologies of dietary assessment and nutritional status to evaluate this relationship.

Association of Combined Patterns of Tobacco and Cannabis Use in Adolescence With Psychotic Experiences

PubMed Central

Gage, Suzanne H.; Heron, Jon; Hickman, Matthew; Lewis, Glyn; Munafò, Marcus R.; Zammit, Stanley

2018-01-01

Importance There is concern about potentially causal effects of tobacco use on psychosis, but epidemiological studies have been less robust in attempts to minimize effects of confounding than studies of cannabis use have been. Objectives To examine the association of patterns of cigarette and cannabis use with preceding and subsequent psychotic experiences, and to compare effects of confounding across these patterns. Design, Setting, and Participants This cohort study used data from the Avon Longitudinal Study of Parents and Children, which initially consisted of 14 062 children. Data were collected periodically from September 6, 1990, with collection ongoing, and analyzed from August 8, 2016, through June 14, 2017. Cigarette and cannabis use data were summarized using longitudinal latent class analysis to identify longitudinal classes of substance use. Associations between classes and psychotic experiences at age 18 years were assessed. Exposures Depending on the analysis model, exposures were longitudinal classes of substance use or psychotic experiences at age 12 years. Main Outcomes and Measures Logistic regression was used to examine the associations between substance use longitudinal classes and subsequent onset of psychotic experiences. Results Longitudinal classes were derived using 5300 participants (56.1% female) who had at least 3 measures of cigarette and cannabis use from ages 14 to 19 years. Prior to adjusting for a range of potential confounders, there was strong evdience that early-onset cigarette-only use (4.3%), early-onset cannabis use (3.2%), and late-onset cannabis use (11.9%) (but not later-onset cigarette-only use [14.8%]) latent classes were associated with increased psychotic experiences compared with nonusers (65.9%) (omnibus P < .001). After adjusting for confounders, the association for early-onset cigarette-only use attenuated substantially (unadjusted odds ratio [OR], 3.03; 95% CI, 1.13-8.14; adjusted OR, 1.78; 95% CI, 0.54-5.88), whereas those for early-onset cannabis use (adjusted OR, 3.70; 95% CI, 1.66-8.25) and late-onset cannabis use (adjusted OR, 2.97; 95% CI, 1.63-5.40) remained consistent. Conclusions and Relevance In this study, our findings indicate that while individuals who use cannabis or cigarettes during adolescence have an increased risk of subsequent psychotic experiences, epidemiological evidence is substantively more robust for cannabis use than it is for tobacco use. PMID:29344610

Blood eosinophil count thresholds and exacerbations in patients with chronic obstructive pulmonary disease.

PubMed

Yun, Jeong H; Lamb, Andrew; Chase, Robert; Singh, Dave; Parker, Margaret M; Saferali, Aabida; Vestbo, Jørgen; Tal-Singer, Ruth; Castaldi, Peter J; Silverman, Edwin K; Hersh, Craig P

2018-06-01

Eosinophilic airway inflammation in patients with chronic obstructive pulmonary disease (COPD) is associated with exacerbations and responsivity to steroids, suggesting potential shared mechanisms with eosinophilic asthma. However, there is no consistent blood eosinophil count that has been used to define the increased exacerbation risk. We sought to investigate blood eosinophil counts associated with exacerbation risk in patients with COPD. Blood eosinophil counts and exacerbation risk were analyzed in patients with moderate-to-severe COPD by using 2 independent studies of former and current smokers with longitudinal data. The Genetic Epidemiology of COPD (COPDGene) study was analyzed for discovery (n = 1,553), and the Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints (ECLIPSE) study was analyzed for validation (n = 1,895). A subset of the ECLIPSE study subjects were used to assess the stability of blood eosinophil counts over time. COPD exacerbation risk increased with higher eosinophil counts. An eosinophil count threshold of 300 cells/μL or greater showed adjusted incidence rate ratios for exacerbations of 1.32 in the COPDGene study (95% CI, 1.10-1.63). The cutoff of 300 cells/μL or greater was validated for prospective risk of exacerbation in the ECLIPSE study, with adjusted incidence rate ratios of 1.22 (95% CI, 1.06-1.41) using 3-year follow-up data. Stratified analysis confirmed that the increased exacerbation risk associated with an eosinophil count of 300 cells/μL or greater was driven by subjects with a history of frequent exacerbations in both the COPDGene and ECLIPSE studies. Patients with moderate-to-severe COPD and blood eosinophil counts of 300 cells/μL or greater had an increased risk exacerbations in the COPDGene study, which was prospectively validated in the ECLIPSE study. Copyright © 2018 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Income inequality is associated with adolescent fertility in Brazil: a longitudinal multilevel analysis of 5,565 municipalities.

PubMed

Chiavegatto Filho, Alexandre D P; Kawachi, Ichiro

2015-02-07

Brazil has one of the highest adolescent fertility rates in the world. Income inequality has been frequently linked to overall adolescent health, but studies that analyzed its association with adolescent fertility have been performed only in developed countries. Brazil, in the past decade, has presented a rare combination of increasing per capita income and decreasing income inequality, which could influence future desirable pathways for other countries. We analyzed every live birth from 2000 and from 2010 in each of the 5,565 municipalities of Brazil, a total of 6,049,864 births, which included 1,247,145 (20.6%) births from women aged 15 to 19. Income inequality was assessed by the Gini Coefficient and adolescent fertility by the ratio between the number of live births from women aged 15 to 19 and the number of women aged 15 to 19, calculated for each municipality. We first applied multilevel models separately for 2000 and 2010 to test the cross-sectional association between income inequality and adolescent fertility. We then fitted longitudinal first-differences multilevel models to control for time-invariant effects. We also performed a sensitivity analysis to include only municipality with satisfactory birth record coverage. Our results indicate a consistent and positive association between income inequality and adolescent fertility. After controlling for per capita income, college access, youth homicide rate and adult fertility, higher income inequality was significantly associated with higher adolescent fertility for both 2000 and 2010. The longitudinal multilevel models found similar results. The sensitivity analysis indicated that the results for the association between income inequality and adolescent fertility were robust. Adult fertility was also significantly associated with adolescent fertility in the cross-sectional and longitudinal models. Income inequality is expected to be a leading concern for most countries in the near future. Our results suggest that changes in income inequality are positively and consistently associated with changes in adolescent fertility.

Is Child Abuse Associated with Adolescent Obesity? A Population Cohort Study.

PubMed

Hawton, Katherine; Norris, Tom; Crawley, Esther; Shield, Julian P H

Child abuse is associated with obesity in adulthood through multiple mechanisms. However, little is known about the relationship between abuse and obesity during adolescence. The aim of this study was to investigate, using a birth cohort, whether there is an association between child abuse and overweight or obesity in adolescence. This study utilizes data from the Avon Longitudinal Study of Parents and Children, a prospective cohort study based in South West England. Using data from the 4205 children with complete data at 13 and 16 years, we analyzed body mass index (BMI) and anonymous parental report of abuse. Abuse was categorized as emotional, physical, or sexual. A sub-sample of 3429 had BMI recorded at 18 years, enabling a longitudinal analysis of BMI trajectories. Using linear and logistic regression analysis, adjusting for sex and family adversity, no association was found between child abuse and BMI, BMI Z-scores, overweight, or obesity, at 13 or 16 years, with all confidence intervals straddling the null. There was weak evidence of a negative association between physical and emotional abuse and BMI trajectories between 13 and 18 years. No relationship was found between child abuse and adolescent obesity in this cohort. This challenges the assumption that adolescent obesity is linked to previous child abuse, as demonstrated for obesity in adult life. A further longitudinal study utilizing both parental and child reports with data record linkage, to improve reporting of abuse, and including neglect as an abuse category, would be desirable.

The influence of natural and anthropic environmental variables on the structure and spatial distribution along longitudinal gradient of macroinvertebrate communities in southern Brazilian streams

PubMed Central

Batalla Salvarrey, Andrea Vanessa; Kotzian, Carla Bender; Spies, Márcia Regina; Braun, Bruna

2014-01-01

Abstract Southern Brazilian rivers and streams have been intensively affected by human activities, especially agriculture and the release of untreated domestic sewage. However, data about the aquatic macroinvertebrates in these streams are scarce and limited to only certain groups. In addition, studies focusing on the structure and spatial distribution of these communities are lacking. This study analyzed the effects of natural and anthropic variables on the community structure of macroinvertebrates along a longitudinal gradient in three microbasins located in a region of landscape transition in the state of Rio Grande do Sul, Brazil. Sampling was conducted in the Vacacaí-Mirim River (August 2008) and in the Ibicuí-Mirim and Tororaipí rivers (August 2009) following an environmental gradient including 1 st , 2 nd , 3 rd , and 4 th order segments. Local natural factors that were analyzed include water temperature, pH, electrical conductivity, dissolved oxygen, substrate granulometry, and the presence of aquatic vegetation. Anthropic variables that were analyzed include including bank erosion, land use, urbanization, riparian deforestation, and fine sediments input. A total of 42 families and 129 taxa were found, with predominance of environmentally tolerant taxa. Geological context (landscape transition and large hydrographic basins) tended to influence natural environmental factors along the rivers’ longitudinal gradients. However, changes in anthropic variables were not affected by these geological differences and therefore did not correlate with patterns of spatial distribution in macroinvertebrate communities. Only 1 st order stream segments showed a community composition with high richness of taxa intolerant to anthropic disturbance. Richness as a whole tended to be higher in 3 rd to 4 th order set of segments, but this trend was a result of local anthropic environmental disturbances. Future inventories conducted in similar landscape transition regions of Brazil, for conservation purposes, must consider stream segments of different orders, microbasins, and major basins in order to obtain data that faithfully reflect the regional diversity. Additionally, it is necessary to consider environmental gradients of land use and anthropic impacts in order to suggest appropriate strategies for conserving the environmental integrity of streams. PMID:25373160

Boosted Multivariate Trees for Longitudinal Data

PubMed Central

Pande, Amol; Li, Liang; Rajeswaran, Jeevanantham; Ehrlinger, John; Kogalur, Udaya B.; Blackstone, Eugene H.; Ishwaran, Hemant

2017-01-01

Machine learning methods provide a powerful approach for analyzing longitudinal data in which repeated measurements are observed for a subject over time. We boost multivariate trees to fit a novel flexible semi-nonparametric marginal model for longitudinal data. In this model, features are assumed to be nonparametric, while feature-time interactions are modeled semi-nonparametrically utilizing P-splines with estimated smoothing parameter. In order to avoid overfitting, we describe a relatively simple in sample cross-validation method which can be used to estimate the optimal boosting iteration and which has the surprising added benefit of stabilizing certain parameter estimates. Our new multivariate tree boosting method is shown to be highly flexible, robust to covariance misspecification and unbalanced designs, and resistant to overfitting in high dimensions. Feature selection can be used to identify important features and feature-time interactions. An application to longitudinal data of forced 1-second lung expiratory volume (FEV1) for lung transplant patients identifies an important feature-time interaction and illustrates the ease with which our method can find complex relationships in longitudinal data. PMID:29249866

Transmission and group-delay characterization of coupled resonator optical waveguides apodized through the longitudinal offset technique.

PubMed

Doménech, J D; Muñoz, P; Capmany, J

2011-01-15

In this Letter, the amplitude and group delay characteristics of coupled resonator optical waveguides apodized through the longitudinal offset technique are presented. The devices have been fabricated in silicon-on-insulator technology employing deep ultraviolet lithography. The structures analyzed consisted of three racetracks resonators uniform (nonapodized) and apodized with the aforementioned technique, showing a delay of 5 ± 3 ps and 4 ± 0.5 ps over 1.6 and 1.4 nm bandwidths, respectively.

The relationship between entomological indicators of Aedes aegypti abundance and dengue virus infection

PubMed Central

Stoddard, Steven T.; Barker, Christopher M.; Van Rie, Annelies; Messer, William B.; Meshnick, Steven R.; Morrison, Amy C.; Scott, Thomas W.

2017-01-01

Routine entomological monitoring data are used to quantify the abundance of Ae. aegypti. The public health utility of these indicators is based on the assumption that greater mosquito abundance increases the risk of human DENV transmission, and therefore reducing exposure to the vector decreases incidence of infection. Entomological survey data from two longitudinal cohort studies in Iquitos, Peru, linked with 8,153 paired serological samples taken approximately six months apart were analyzed. Indicators of Ae. aegypti density were calculated from cross-sectional and longitudinal entomological data collected over a 12-month period for larval, pupal and adult Ae. aegypti. Log binomial models were used to estimate risk ratios (RR) to measure the association between Ae. aegypti abundance and the six-month risk of DENV seroconversion. RRs estimated using cross-sectional entomological data were compared to RRs estimated using longitudinal data. Higher cross-sectional Ae. aegypti densities were not associated with an increased risk of DENV seroconversion. Use of longitudinal entomological data resulted in RRs ranging from 1.01 (95% CI: 1.01, 1.02) to 1.30 (95% CI: 1.17, 1.46) for adult stage density estimates and RRs ranging from 1.21 (95% CI: 1.07, 1.37) to 1.75 (95% CI: 1.23, 2.5) for categorical immature indices. Ae. aegypti densities calculated from longitudinal entomological data were associated with DENV seroconversion, whereas those measured cross-sectionally were not. Ae. aegypti indicators calculated from cross-sectional surveillance, as is common practice, have limited public health utility in detecting areas or populations at high risk of DENV infection. PMID:28333938

Rural N(SO) and German middle-class mothers' interaction with their 3- and 6-month-old infants: A longitudinal cross-cultural analysis.

PubMed

Lamm, Bettina; Gudi, Helene; Fassbender, Ina; Freitag, Claudia; Graf, Frauke; Goertz, Claudia; Spangler, Sibylle; Teubert, Manuel; Knopf, Monika; Lohaus, Arnold; Schwarzer, Gudrun; Keller, Heidi

2015-08-01

This study aims to analyze culture-specific development of maternal interactional behavior longitudinally. Rural Cameroonian Nso mothers (n = 72) and German middle-class mothers (n = 106) were observed in free-play interactions with their 3- and 6-month-old infants. Results reveal the expected shift from a social to a nonsocial focus only in the German middle-class mothers' play interactions but not the rural Nso mothers' play. Nso mothers continue their proximal interactional style with a focus on body contact and body stimulation, whereas German middle-class mothers prefer a distal style of interaction with increasing object-centeredness. These cultural differences are in line with broader cultural models and become more accentuated as the infants grow older. (c) 2015 APA, all rights reserved).

Analysis and quantification of endovascular coil distribution inside saccular aneurysms using histological images.

PubMed

Morales, Hernán G; Larrabide, Ignacio; Geers, Arjan J; Dai, Daying; Kallmes, David F; Frangi, Alejandro F

2013-11-01

Endovascular coiling is often performed by first placing coils along the aneurysm wall to create a frame and then by filling up the aneurysm core. However, little attention has been paid to quantifying this filling strategy and to see how it changes for different packing densities. The purpose of this work is to analyze and quantify endovascular coil distribution inside aneurysms based on serial histological images of experimental aneurysms. Seventeen histological images from 10 elastase-induced saccular aneurysms in rabbits treated with coils were studied. In-slice coil density, defined as the area taken up by coil winds, was calculated on each histological image. Images were analyzed by partitioning the aneurysm along its longitudinal and radial axes. Coil distribution was quantified by measuring and comparing the in-slice coil density of each partition. Mean total in-slice coil density was 22.0 ± 6.2% (range 10.1-30.2%). The density was non-significantly different (p = 0.465) along the longitudinal axis. A significant difference (p < 0.001) between peripheral and core densities was found. Additionally, the peripheral-core density ratio was observed to be inversely proportional to the total in-slice coil density (R(2)=0.57, p <0.001). This ratio was near unity for high in-slice coil density (around 30%). These findings demonstrate and confirm that coils tend to be located near the aneurysm periphery when few are inserted. However, when more coils are added, the radial distribution becomes more homogeneous. Coils are homogeneously distributed along the longitudinal axis.

Defining the Process of a Cardiovascular Risk Assessment Program: Lessons Learnt From Cardiac Assessment of Elite Soccer Players in the United Kingdom.

PubMed

Speers, Christopher; Seth, Ajai Narain; Patel, Kiran Chhaganbhai; Rakhit, Dhrubo Jyoti; Gillett, Mark James

2017-12-14

Retrospectively analyze the cardiac assessment process for elite soccer players, and provide team physicians with a systematic guide to managing longitudinal cardiac risk. Descriptive Epidemiology Study. Cardiac assessments incorporating clinical examination, 12-lead ECG, echocardiography, and health questionnaire. Soccer players at 5 professional clubs in England, the United Kingdom. Data was retrospectively collected, inspected, and analyzed to determine their clinical management and subsequent follow-up. Over 2 years, 265 soccer players, aged 13 to 37 years with 66% of white European ethnicity, were included in the cohort. Eleven percent had "not-normal" assessments, of these assessments, 83% were considered gray screens, falling into three broad categories: structural cardiac features (including valvular abnormalities), functional cardiac features, and electrocardiogram changes. After cardiology consultation, all assessments were grouped into low, enhanced and high-risk categories for ongoing longitudinal risk management. Overall clear-cut pathology was identified in 2%. Cardiovascular assessment is a vital tool in identifying athletes at risk of sudden cardiac death to mitigate their risk through surveillance, intervention, or participation restriction. The decision whether a player is fit to play or not requires a robust risk assessment followed by input from a multidisciplinary team that includes both the team physician and cardiologist. This educational article proposes a clinical management pathway to aid clinicians with this process. Sudden cardiac death is the important medical cause of death during exercise. The team physician should assume responsibility for the management of the longitudinal risk of their players' cardiac assessments in conjunction with sports cardiologist.

The interplay between sleep behavior and affect in elementary school children's daily life.

PubMed

Könen, Tanja; Dirk, Judith; Leonhardt, Anja; Schmiedek, Florian

2016-10-01

Recent reviews raised the idea of a bidirectional relation between sleep behavior and affect in adults, but little is known about this interplay in general and especially regarding children. In this micro-longitudinal study, the interplay of sleep and affect was captured directly in children's daily life context in and out of school through ambulatory assessment. For 31 consecutive days, 110 elementary school children (8-11 years old) provided information about their last night's sleep and reported their current affect at four daily occasions in school and at home on smartphones. A multilevel approach was used to analyze the relation between sleep and affect the next day (morning, noon, and afternoon) and the relation between evening affect and subsequent sleep. At the within-person level, sleep quality was related to all observed facets of affect the next day and the strongest effects were found in the morning. The effect of sleep quality on positive affect was particularly pronounced for children who on average went to bed early and slept long. There were, however, no direct within-person effects of sleep quantity on affect. Furthermore, evening affect was related to subsequent sleep. The findings support the idea of a bidirectional relation between affect and sleep in children's daily life (including school). They suggest that good sleep provides a basis and resource for children's affective well-being the next day and demonstrate the importance of analyzing within-person variations of children's sleep. Micro-longitudinal findings can contribute to explain how macro-longitudinal relations between sleep and affect develop over time. Copyright © 2016 Elsevier Inc. All rights reserved.

Changes in the Game Characteristics of a Badminton Match: A Longitudinal Study through the Olympic Game Finals Analysis in Men's Singles.

PubMed

Laffaye, Guillaume; Phomsoupha, Michael; Dor, Frédéric

2015-09-01

The goal of this study was to analyze, through a longitudinal study, the Olympic Badminton Men's singles finals from the Barcelona Games (1992) to the London Games (2012) to assess some changes of the Badminton game characteristics. Six Olympic finals have been analyzed based on the official video of the Olympic Games (OG) through the temporal structure and with a notational approach. In total, 537 rallies and 5537 strokes have been analyzed. The results show a change in the game's temporal structure: a significant difference in the rally time, rest time and number of shots per rally (all p<0.0001; 0.09 < η(2) < 0.16). Moreover, the shot frequency shows a 34.0% increase (p<0.000001; η(2) = 0.17), whereas the work density revealed a 58.2% decrease (from 78% to 30.8%) as well as the effective playing time (-34.5% from 34.7±1.4% to 22.7±1.4%). This argues for an increase in the intensity of the game and a necessity for the player to use a longer resting time to recover. Lastly, the strokes distribution and the percentage of unforced and forced mistakes did not show any differences throughout the OG analysis, except for the use of the clear. This results impact on the way the training of Badminton players should be designed, especially in the temporal structure and intensity. Key pointsBadminton game has become faster, with an important increase in the shot frequency (+34%)The effective playing time has decreased between first to last Olympic Games (-34.5%)The strokes distribution and the percentage of unforced and forced errors show no differences through the OG analysis, except for the use of the clear.

Migraine and cognitive function: Baseline findings from the Brazilian Longitudinal Study of Adult Health: ELSA-Brasil.

PubMed

Pellegrino Baena, Cristina; Goulart, Alessandra Carvalho; Santos, Itamar de Souza; Suemoto, Claudia Kimie; Lotufo, Paulo Andrade; Bensenor, Isabela Judith

2017-01-01

Background The association between migraine and cognitive performance is unclear. We analyzed whether migraine is associated with cognitive performance among participants of the Brazilian Longitudinal Study of Adult Health, ELSA-Brasil. Methods Cross-sectional analysis, including participants with complete information about migraine and aura at baseline. Headache status (no headaches, non-migraine headaches, migraine without aura and migraine with aura), based on the International Headache Society classification, was used as the dependent variable in the multilinear regression models, using the category "no headache" as reference. Cognitive performance was measured with the Consortium to Establish a Registry for Alzheimer's Disease word list memory test (CERAD-WLMT), the semantic fluency test (SFT), and the Trail Making Test version B (TMTB). Z-scores for each cognitive test and a composite global score were created and analyzed as dependent variables. Multivariate models were adjusted for age, gender, education, race, coronary heart disease, heart failure, hypertension, diabetes, dyslipidemia, body mass index, smoking, alcohol use, physical activity, depression, and anxiety. In women, the models were further adjusted for hormone replacement therapy. Results We analyzed 4208 participants. Of these, 19% presented migraine without aura and 10.3% presented migraine with aura. All migraine headaches were associated with poor cognitive performance (linear coefficient β; 95% CI) at TMTB -0.083 (-0.160; -0.008) and poorer global z-score -0.077 (-0.152; -0.002). Also, migraine without aura was associated with poor cognitive performance at TMTB -0.084 (-0.160, -0.008 and global z-score -0.077 (-0.152; -0.002). Conclusion In participants of the ELSA-study, all migraine headaches and migraine without aura were significantly and independently associated with poorer cognitive performance.

Observations and implications of large-amplitude longitudinal oscillations in a solar filament

DOE Office of Scientific and Technical Information (OSTI.GOV)

Luna, M.; Knizhnik, K.; Muglach, K.

On 2010 August 20, an energetic disturbance triggered large-amplitude longitudinal oscillations in a nearby filament. The triggering mechanism appears to be episodic jets connecting the energetic event with the filament threads. In the present work, we analyze this periodic motion in a large fraction of the filament to characterize the underlying physics of the oscillation as well as the filament properties. The results support our previous theoretical conclusions that the restoring force of large-amplitude longitudinal oscillations is solar gravity, and the damping mechanism is the ongoing accumulation of mass onto the oscillating threads. Based on our previous work, we usedmore » the fitted parameters to determine the magnitude and radius of curvature of the dipped magnetic field along the filament, as well as the mass accretion rate onto the filament threads. These derived properties are nearly uniform along the filament, indicating a remarkable degree of cohesiveness throughout the filament channel. Moreover, the estimated mass accretion rate implies that the footpoint heating responsible for the thread formation, according to the thermal nonequilibrium model, agrees with previous coronal heating estimates. We estimate the magnitude of the energy released in the nearby event by studying the dynamic response of the filament threads, and discuss the implications of our study for filament structure and heating.« less

Identity Formation in Adulthood: A Longitudinal Study from Age 27 to 50

PubMed Central

Fadjukoff, Päivi; Pulkkinen, Lea; Kokko, Katja

2016-01-01

ABSTRACT Longitudinal patterns of identity formation were analyzed in a representative cohort group of Finnish men and women born in 1959 across ages 27, 36, 42, and 50. The data were drawn from the Jyväskylä Longitudinal Study of Personality. Identity status (diffused, moratorium, foreclosed, achieved) from all four ages was available for 172 participants (54% females). Marcia’s Identity Status Interview used in this research included five domains: religious beliefs, political identity, occupational career, intimate relationships, and lifestyle. The findings indicated great variability in identity status across domains at each age level, and the identity trajectories fluctuated from age 27 to 50. The developmental trend from age 27 to 50 was moderately progressive (toward achievement) for the five domains and for overall identity, with the exception of a slightly regressive trend in male religious identity. Remaining stable in the same status category across the four measurements was rare and emerged only for diffusion in the ideological domains. Women generally outnumbered men in identity achievement at earlier ages, but the gender differences diminished in most domains at age 50, except in religious identity. In women overall diffusion decreased over time, but in men it remained at about 20% at ages 42 and 50. PMID:27019650

Emotion regulation predicts marital satisfaction: more than a wives' tale.

PubMed

Bloch, Lian; Haase, Claudia M; Levenson, Robert W

2014-02-01

Emotion regulation is generally thought to be a critical ingredient for successful interpersonal relationships. Ironically, few studies have investigated the link between how well spouses regulate emotion and how satisfied they are with their marriages. We utilized data from a 13-year, 3-wave longitudinal study of middle-aged (40-50 years old) and older (60-70 years old) long-term married couples, focusing on the associations between downregulation of negative emotion (measured during discussions of an area of marital conflict at Wave 1) and marital satisfaction (measured at all 3 waves). Downregulation of negative emotion was assessed by determining how quickly spouses reduced signs of negative emotion (in emotional experience, emotional behavior, and physiological arousal) after negative emotion events. Data were analyzed using actor-partner interdependence modeling. Findings showed that (a) greater downregulation of wives' negative experience and behavior predicted greater marital satisfaction for wives and husbands concurrently and (b) greater downregulation of wives' negative behavior predicted increases in wives' marital satisfaction longitudinally. Wives' use of constructive communication (measured between Waves 1 and 2) mediated the longitudinal associations. These results show the benefits of wives' downregulation of negative emotion during conflict for marital satisfaction and point to wives' constructive communication as a mediating pathway. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Emotion regulation predicts marital satisfaction: More than a wives’ tale

PubMed Central

Bloch, Lian; Haase, Claudia M.; Levenson, Robert W.

2014-01-01

Emotion regulation is generally thought to be a critical ingredient for successful interpersonal relationships. Ironically, few studies have investigated the link between how well spouses regulate emotion and how satisfied they are with their marriages. We utilized data from a 13-year, 3-wave longitudinal study of middle-aged (40–50 years old) and older (60–70 years old) long-term married couples, focusing on the associations between downregulation of negative emotion (measured during discussions of an area of marital conflict at Wave 1) and marital satisfaction (measured at all three waves). Downregulation of negative emotion was assessed by determining how quickly spouses reduced signs of negative emotion (in emotional experience, emotional behavior, and physiological arousal) after negative emotion events. Data were analyzed using actor-partner interdependence modeling. Findings showed that (a) greater downregulation of wives’ negative experience and behavior predicted greater marital satisfaction for wives and husbands concurrently and (b) greater downregulation of wives’ negative behavior predicted increases in wives’ marital satisfaction longitudinally. Wives’ use of constructive communication (measured between Waves 1 and 2) mediated the longitudinal associations. These results show the benefits of wives’ downregulation of negative emotion during conflict for marital satisfaction and point to wives’ constructive communication as a mediating pathway. PMID:24188061

Graduation Outcomes of Students Who Entered New York City Public Schools in Grade 5 or 6 as English Learner Students. REL 2017-237

ERIC Educational Resources Information Center

Kieffer, Michael J.; Parker, Caroline E.

2017-01-01

This longitudinal study analyzes high school graduation outcomes of students who entered New York City public schools in grade 5 or 6 as English learner students. It extends the work of Kieffer and Parker (2016) by investigating the high school graduation rates and the types of diploma earned by the 1,734 students who entered New York City public…

Phonological Skills and Ability to Perceive Auditorily the Structure of a Word at the Level of a Single Phoneme at Ages 2-6

ERIC Educational Resources Information Center

Suortti, Outi; Lipponen, Lasse

2014-01-01

The present study is the first part of a longitudinal research project investigating whether children become more aware of phonemes or rhyming when they learn letters or letter sounds or even begin to read, and if so how. For the present paper, the phonological awareness of young children aged 2-6 years was analyzed, particularly their auditory…

Apri Gli Occi E Hai Le Cervello Nel Capo: Open Your Eyes and Keep Your Brains in Your Head: Narrative Stories from Italian Immigrant Women--Pasqualina, Susan, Matilde, & Filomena

ERIC Educational Resources Information Center

Pace, Josefa

2013-01-01

This three and a half year longitudinal study focused upon the social and cultural identities of four Italian women. In understanding and interpreting their identities, ethnographic data was analyzed through discourse and narrative analysis and presented in ways that recognized the importance of caring for their lives (Brandt, 2013), staying close…

Polylingual Development among Turkish Speakers in a Danish Primary School--A Critical View on the Fourth Grade Slump

ERIC Educational Resources Information Center

Møller, Janus Spindler; Jørgensen, J. Normann; Holmen, Anne

2014-01-01

In this paper we report on a longitudinal study of the linguistic development among Turkish-speaking children in Denmark. A series of data were collected from a group of children attending a public school in Køge during the period 1989-1998 and from the same group--now in their 20s--in 2006-2007. The data set has been analyzed from a number of…

Contributions on the Subject of Longitudinal Movements of Aircraft in Wind Shears. Ph.D. Thesis - Technischen Univ., 1983

NASA Technical Reports Server (NTRS)

Krauspe, P.

1985-01-01

The effect of downburst-type wind shears on the longitudinal dynamic behavior of an unguided aircraft is simulated numerically on the basis of published meteorological data and the flight characteristics of an A300-B passenger jet. The nonlinear differential equations of the aircraft motion are linearized by conventional methods, and the wind effects are introduced via the linear derivatives of the wind components referred to the wind gradients to obtain simplified technical models of the longitudinal response to all possible types of constant-gradient wind shears during the first 20-60 sec. Graphs, maps, and diagrams are provided, and a number of accidents presumed to have involved wind shears are analyzed in detail.

Alternative Approaches to Assessing Nonresponse Bias in Longitudinal Survey Estimates: An Application to Substance-Use Outcomes Among Young Adults in the United States

PubMed Central

West, Brady Thomas; McCabe, Sean Esteban

2017-01-01

Abstract We evaluated alternative approaches to assessing and correcting for nonresponse bias in a longitudinal survey. We considered the changes in substance-use outcomes over a 3-year period among young adults aged 18–24 years (n = 5,199) in the United States, analyzing data from the National Epidemiologic Survey on Alcohol and Related Conditions. This survey collected a variety of substance-use information from a nationally representative sample of US adults in 2 waves: 2001–2002 and 2004–2005. We first considered nonresponse rates in the second wave as a function of key substance-use outcomes in wave 1. We then evaluated 5 alternative approaches designed to correct for nonresponse bias under different attrition mechanisms, including weighting adjustments, multiple imputation, selection models, and pattern-mixture models. Nonignorable attrition in a longitudinal survey can lead to bias in estimates of change in certain health behaviors over time, and only selected procedures enable analysts to assess the sensitivity of their inferences to different assumptions about the extent of nonignorability. We compared estimates based on these 5 approaches, and we suggest a road map for assessing the risk of nonresponse bias in longitudinal studies. We conclude with directions for future research in this area given the results of our evaluations. PMID:28338839

Assessment of gastric emptying in non-obese diabetic mice using a [13C]-octanoic acid breath test.

PubMed

Creedon, Christopher T; Verhulst, Pieter-Jan; Choi, Kyoung M; Mason, Jessica E; Linden, David R; Szurszewski, Joseph H; Gibbons, Simon J; Farrugia, Gianrico

2013-03-23

Gastric emptying studies in mice have been limited by the inability to follow gastric emptying changes in the same animal since the most commonly used techniques require killing of the animals and postmortem recovery of the meal(1,2). This approach prevents longitudinal studies to determine changes in gastric emptying with age and progression of disease. The commonly used [(13)C]-octanoic acid breath test for humans(3) has been modified for use in mice(4-6) and rats(7) and we previously showed that this test is reliable and responsive to changes in gastric emptying in response to drugs and during diabetic disease progression(8). In this video presentation the principle and practical implementation of this modified test is explained. As in the previous study, NOD LtJ mice are used, a model of type 1 diabetes(9). A proportion of these mice develop the symptoms of gastroparesis, a complication of diabetes characterized by delayed gastric emptying without mechanical obstruction of the stomach(10). This paper demonstrates how to train the mice for testing, how to prepare the test meal and obtain 4 hr gastric emptying data and how to analyze the obtained data. The carbon isotope analyzer used in the present study is suitable for the automatic sampling of the air samples from up to 12 mice at the same time. This technique allows the longitudinal follow-up of gastric emptying from larger groups of mice with diabetes or other long-standing diseases.

Vascular risk factors and neuropsychiatric symptoms in Alzheimer's disease: the Cache County Study.

PubMed

Steinberg, Martin; Hess, Kyle; Corcoran, Chris; Mielke, Michelle M; Norton, Maria; Breitner, John; Green, Robert; Leoutsakos, Jeannie; Welsh-Bohmer, Kathleen; Lyketsos, Constantine; Tschanz, Joann

2014-02-01

Knowledge of potentially modifiable risk factors for neuropsychiatric symptoms (NPS) in Alzheimer's disease (AD) is important. This study longitudinally explores modifiable vascular risk factors for NPS in AD. Participants enrolled in the Cache County Study on Memory in Aging with no dementia at baseline were subsequently assessed over three additional waves, and those with incident (new onset) dementia were invited to join the Dementia Progression Study for longitudinal follow-up. A total of 327 participants with incident AD were identified and assessed for the following vascular factors: atrial fibrillation, hypertension, diabetes mellitus, angina, coronary artery bypass surgery, myocardial infarction, cerebrovascular accident, and use of antihypertensive or diabetes medicines. A vascular index (VI) was also calculated. NPS were assessed over time using the Neuropsychiatric Inventory (NPI). Affective and Psychotic symptom clusters were assessed separately. The association between vascular factors and change in NPI total score was analyzed using linear mixed model and in symptom clusters using a random effects model. No individual vascular risk factors or the VI significantly predicted change in any individual NPS. The use of antihypertensive medications more than four times per week was associated with higher total NPI and Affective cluster scores. Use of antihypertensive medication was associated with higher total NPI and Affective cluster scores. The results of this study do not otherwise support vascular risk factors as modifiers of longitudinal change in NPS in AD. Copyright © 2013 John Wiley & Sons, Ltd.

Child incarceration and long-term adult health outcomes: a longitudinal study.

PubMed

Barnert, Elizabeth S; Abrams, Laura S; Tesema, Lello; Dudovitz, Rebecca; Nelson, Bergen B; Coker, Tumaini; Bath, Eraka; Biely, Christopher; Li, Ning; Chung, Paul J

2018-03-12

Purpose Although incarceration may have life-long negative health effects, little is known about associations between child incarceration and subsequent adult health outcomes. The paper aims to discuss this issue. Design/methodology/approach The authors analyzed data from 14,689 adult participants in the National Longitudinal Study of Adolescent to Adult Health (Add Health) to compare adult health outcomes among those first incarcerated between 7 and 13 years of age (child incarceration); first incarcerated at>or=14 years of age; and never incarcerated. Findings Compared to the other two groups, those with a history of child incarceration were disproportionately black or Hispanic, male, and from lower socio-economic strata. Additionally, individuals incarcerated as children had worse adult health outcomes, including general health, functional limitations (climbing stairs), depressive symptoms, and suicidality, than those first incarcerated at older ages or never incarcerated. Research limitations/implications Despite the limitations of the secondary database analysis, these findings suggest that incarcerated children are an especially medically vulnerable population. Practical implications Programs and policies that address these medically vulnerable children's health needs through comprehensive health and social services in place of, during, and/or after incarceration are needed. Social implications Meeting these unmet health and social service needs offers an important opportunity to achieve necessary health care and justice reform for children. Originality/value No prior studies have examined the longitudinal relationship between child incarceration and adult health outcomes.

Etiology of the stability of reading difficulties: the longitudinal twin study of reading disabilities.

PubMed

Astrom, Raven L; Wadsworth, Sally J; DeFries, John C

2007-06-01

Results obtained from previous longitudinal studies of reading difficulties indicate that reading deficits are generally stable. However, little is known about the etiology of this stability. Thus, the primary objective of this first longitudinal twin study of reading difficulties is to provide an initial assessment of genetic and environmental influences on the stability of reading deficits. Data were analyzed from a sample of 56 twin pairs, 18 identical (monozygotic, MZ) and 38 fraternal (dizygotic, DZ), in which at least one member of each pair was classified as reading-disabled in the Colorado Learning Disabilities Research Center, and on whom follow-up data were available. The twins were tested at two time points (average age of 10.3 years at initial assessment and 16.1 years at follow-up). A composite measure of reading performance (PIAT Reading Recognition, Reading Comprehension and Spelling) was highly stable, with a stability correlation of .84. Data from the initial time point were first subjected to univariate DeFries-Fulker multiple regression analysis and the resulting estimate of the heritability of the group deficit (h2g) was .84 (+/-.26). When the initial and follow-up data were then fitted to a bivariate extension of the basic DF model, bivariate heritability was estimated at .65, indicating that common genetic influences account for approximately 75% of the stability between reading measures at the two time points.

Perceptions of the Coach–Athlete Relationship Predict the Attainment of Mastery Achievement Goals Six Months Later: A Two-Wave Longitudinal Study among F. A. Premier League Academy Soccer Players

PubMed Central

Nicholls, Adam R.; Earle, Keith; Earle, Fiona; Madigan, Daniel J.

2017-01-01

All football teams that compete within the F. A. Premier League possess an academy, whose objective is to produce more and better home-grown players that are capable of playing professionally. These young players spend a large amount of time with their coach, but little is known about player’s perception of the coach–athlete relationship within F. A. Premier League Academies. The objectives of this study were to examine whether perceptions of the coach–athlete relationship changed over six months and if the coach–athlete relationship predicted self-reported goal achievement among F. A. Premier League academy players. This study included cross-sectional (n = 104) and longitudinal (n = 52) assessments, in which academy soccer players completed a measure of the coach–athlete relationship and goal achievement across either one or two time periods. The cross-sectional data were subjected to bivariate correlations, whereas the longitudinal data were analyzed using multiple regressions. Perceptions of the coach–athlete relationship remained stable over time. The coach–athlete relationship predicted the achievement of mastery goals six months later. Enhancing the quality of the coach–athlete relationship among elite adolescent athletes appears to be a suitable way of maximizing mastery achievement goals, particularly among developmental athletes who participate in team sports. PMID:28572775

Prediction of BMI at age 11 in a longitudinal sample of the Ulm Birth Cohort Study

PubMed Central

Walter, Viola; Wabitsch, Martin; Rothenbacher, Dietrich; Brenner, Hermann; Schimmelmann, Benno G.

2017-01-01

Obesity is one of the greatest public health challenges in the world with childhood prevalence rates between 20–26% and numerous associated health risks. The aim of the current study was to analyze the 11-year follow-up data of the Ulm Birth Cohort Study (UBCS), to identify whether abnormal eating behavior patterns, especially restrained eating, predict body mass index (BMI) at 11 years of age and to explore other factors known to be longitudinally associated with it. Of the original UBCS, n = 422 children (~ 40% of the original sample) and their parents participated in the 11-year follow-up. BMI at age 8 and 11 as well as information on restrained eating, psychological problems, depressive symptoms, lifestyle, and IQ at age 8 were assessed. Partial Least Squares Structural Equation Modeling (PLS-SEM) was used to predict children’s BMI scores at age 11. PLS-SEM explained 68% of the variance of BMI at age 11, with BMI at age 8 being the most important predictor. Restrained eating, via BMI at age 8 as well as parental BMI, had further weak associations with BMI at age 11; no other predictor was statistically significant. Since established overweight at age 8 already predicts BMI scores at age 11 longitudinally, obesity interventions should be implemented in early childhood. PMID:28832593

Brief Intervention for Truant Youth Sexual Risk Behavior and Alcohol Use: A Parallel Process Growth Model Analysis

PubMed Central

Dembo, Richard; Briones-Robinson, Rhissa; Ungaro, Rocio; Barrett, Kimberly; Gulledge, Laura; Winters, Ken C.; Belenko, Steven; Karas, Lora M.; Wareham, Jennifer

2011-01-01

Truant youths represent a challenging, yet very promising group of at-risk youth to study. In addition to problems in school, they frequently experience troubled family situations, emotional/ psychological problems, involvement in substance use, and delinquency. Given the problems often experienced by truant youth, it is likely they are engaging in alcohol use and sexual risk behavior at a higher rate, than the general youth population. Identification of these youths’ problems and early placement into effective intervention services would benefit them, their families, and society. The current study presents interim findings from an ongoing, NIDA-funded experimental, Brief Intervention (BI) study involving truant youths and their parent/guardians. Baseline, 3-month, 6-month, and 12-month follow up data were analyzed to determine whether alcohol use and sexual risk behaviors were longitudinally related, examine the effects of the intervention on longitudinal alcohol use and sexual risk behaviors, identify latent subgroups of youths in the data for alcohol use and sexual risk behaviors, and determine whether the intervention influenced these subgroups. Results indicated alcohol use and sexual risk were longitudinally related. Subgroups of youth were also identified based on alcohol use and sexual risk behavior levels and trends. Further, limited treatment effects were observed for alcohol use. Implications of the results for future research and service delivery are considered. PMID:25242878

The dynamics of the relationship between diabetes incidence and low income: longitudinal results from Canada's National Population Health Survey.

PubMed

Dinca-Panaitescu, Mihaela; Dinca-Panaitescu, Serban; Raphael, Dennis; Bryant, Toba; Pilkington, Beryl; Daiski, Isolde

2012-07-01

This paper sheds light on the dynamic relationship between people's experiences of low income and the development of type 2 diabetes (T2DM) by moving beyond the static perspective provided by cross-sectional studies to a long-term approach informed by longitudinal analyses. We analyzed data from the Canadian National Population Health Survey (NPHS) conducted by Statistics Canada from 1994 to 2007. The longitudinal sample is composed of 17,276 respondents (8046 males, 9230 females) 12 years of age or older. We further developed an algorithm to distinguish T2DM from other types of diabetes. Proportional hazard models with time-varying predictors were used to explore the dynamics of the relationship between low income and T2DM. The results suggest that living in low income and experiencing persistent low income are significant precursors of developing T2DM. Being in low income in the previous cycle of T2DM onset was associated with 77% higher risk of T2DM (hazard ratio 1.77; 95% CI: 1.48-2.12). The association between low income and diabetes incidence remains significant after adjusting for age, sex, health behaviors, and psychological distress (hazard ratio 1.24; 95% CI: 1.02-1.52). This study contributes to the under-developed research examining longitudinally the relationship between socioeconomic status and diabetes incidence. Employing this long-term approach, this study calls attention to the primary effect of socioeconomic position on diabetes incidence that cannot be explained entirely by behavioral factors. Findings draw attention to the need to address the role played in T2DM by the inequitable distribution of the social determinants of health. Crown Copyright © 2012. Published by Elsevier Ireland Ltd. All rights reserved.

The Association of Health and Employment in Mature Women: A Longitudinal Study

PubMed Central

Byles, Julie

2012-01-01

Abstract Background Despite a reduction in income inequalities between men and women, there is still a large gap between income and retirement savings of Australian men and women. This is especially true for women who have health or disability problems. Mature age women are closest to retirement and, therefore, have less chance than younger women to build up enough retirement savings and may need to continue working to fund their older age. Continued workforce participation may be particularly difficult for women who are less healthy. Understanding which health problems lead to a decrease in workforce participation among mature age women is crucial. Therefore, this longitudinal study sought to identify which health problems are associated with employment among midage women over time. Methods Data were analyzed from the midage cohort of the Australian Longitudinal Study on Women's Health (ALSWH), which involved 14,200 midage women (aged 45–50 years in 1996). The women have been surveyed four additional times, in 1998, 2001, 2004, and 2007. Generalized estimating equations (GEE) were used to conduct nested multivariate longitudinal analyses. Results The percentages of women who were employed in the years 2001, 2004, and 2007 were 77%, 72%, and 68%, respectively. Results were adjusted for sociodemographic variables. Being employed decreased as physical and mental health deteriorated and with self-reported conditions: diabetes, high blood pressure, depression, anxiety, and other psychiatric conditions. Back pain, arthritis, cancer, obesity, and being a current smoker are associated with employment but not when quality of life is added to the model. Conclusions There were significant associations between health and employment. Understanding these relationships could inform policies and guidelines for preventing declines in employment in mature age women. PMID:22060315

Retinal vessel caliber among people with acquired immunodeficiency syndrome: relationships with visual function.

PubMed

Kalyani, Partho S; Fawzi, Amani A; Gangaputra, Sapna; van Natta, Mark L; Hubbard, Larry D; Danis, Ronald P; Thorne, Jennifer E; Holland, Gary N

2012-03-01

To evaluate relationships between retinal vessel caliber and tests of visual function among people with AIDS. Longitudinal, observational cohort study. We evaluated data for participants without ocular opportunistic infections at initial examination (baseline) in the Longitudinal Studies of the Ocular Complications of AIDS (1998-2008). Visual function was evaluated with best-corrected visual acuity, Goldmann perimetry, automated perimetry (Humphrey Field Analyzer), and contrast sensitivity (CS) testing. Semi-automated grading of fundus photographs (1 eye/participant) determined central retinal artery equivalent (CRAE), central retinal vein equivalent (CRVE), and arteriole-to-venule ratio (AVR) at baseline. Multiple linear regression models, using forward selection, sought independent relationships between indices and visual function variables. Included were 1250 participants. Smaller AVR was associated with reduced visual field by Goldmann perimetry (P = .003) and worse mean deviation (P = .02) on automated perimetry and possibly with worse pattern standard deviation (PSD) on automated perimetry (P = .06). There was a weak association between smaller AVR and worse CS (P = .07). Relationships were independent of antiretroviral therapy and level of immunodeficiency (CD4+ T lymphocyte count, human immunodeficiency virus [HIV] RNA blood level). On longitudinal analysis, retinal vascular indices at baseline did not predict changes in visual function. Variation in retinal vascular indices is associated with abnormal visual function in people with AIDS, manifested by visual field loss and possibly by reduced CS. Relationships are consistent with the hypothesis that HIV-related retinal vasculopathy is a contributing factor to vision dysfunction among HIV-infected individuals. Longitudinal studies are needed to determine whether changes in indices predict change in visual function. Copyright © 2012 Elsevier Inc. All rights reserved.

Measuring vascular reactivity with breath-holds after stroke: a method to aid interpretation of group-level BOLD signal changes in longitudinal fMRI studies.

PubMed

Geranmayeh, Fatemeh; Wise, Richard J S; Leech, Robert; Murphy, Kevin

2015-05-01

Blood oxygenation level-dependent (BOLD) contrast functional magnetic resonance imaging (fMRI) is a widely used technique to map brain function, and to monitor its recovery after stroke. Since stroke has a vascular etiology, the neurovascular coupling between cerebral blood flow and neural activity may be altered, resulting in uncertainties when interpreting longitudinal BOLD signal changes. The purpose of this study was to demonstrate the feasibility of using a recently validated breath-hold task in patients with stroke, both to assess group level changes in cerebrovascular reactivity (CVR) and to determine if alterations in regional CVR over time will adversely affect interpretation of task-related BOLD signal changes. Three methods of analyzing the breath-hold data were evaluated. The CVR measures were compared over healthy tissue, infarcted tissue and the peri-infarct tissue, both sub-acutely (∼2 weeks) and chronically (∼4 months). In this cohort, a lack of CVR differences in healthy tissue between the patients and controls indicates that any group level BOLD signal change observed in these regions over time is unlikely to be related to vascular alterations. CVR was reduced in the peri-infarct tissue but remained unchanged over time. Therefore, although a lack of activation in this region compared with the controls may be confounded by a reduced CVR, longitudinal group-level BOLD changes may be more confidently attributed to neural activity changes in this cohort. By including this breath-hold-based CVR assessment protocol in future studies of stroke recovery, researchers can be more assured that longitudinal changes in BOLD signal reflect true alterations in neural activity. © 2015 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc.

Children's Media Use and Self-Regulation Behavior: Longitudinal Associations in a Nationwide Japanese Study.

PubMed

Inoue, Sachiko; Yorifuji, Takashi; Kato, Tsuguhiko; Sanada, Satoshi; Doi, Hiroyuki; Kawachi, Ichiro

2016-10-01

Objective The effect of media use on child behavior has long been a concern. Although studies have shown robust cross-sectional relations between TV viewing and child behavior, longitudinal studies remain scarce. Methods We analyzed the Longitudinal Survey of Babies, conducted by Japan's Ministry of Health, Labour and Welfare since 2001. Among 53,575 families, 47,010 responded to the baseline survey; they were followed up every year for 8 years. Complete data were available for longitudinal analysis among 32,439 participants. Daily media use (TV viewing and video game-playing hours at ages 3, 4, and 5 years) was used as the main exposure. We employed an index of the children's self-regulatory behavior as the outcome variable. Odds ratios and 95 % confidence intervals (CIs) were estimated. Results Among boys, longer TV-viewing times at ages 4 and 5 were related to problematic self-regulatory behavior. Compared with boys who watched just 1-2 h of TV a day, those who watched it 4-5 h had a 1.79-fold greater risk (CI 1.22-2.64) of problematic self-regulatory behavior, according to parental report. Among girls, similar results were evident at ages 4 and 5 (e.g., adjusted odds ratios for 4-5 h daily viewing versus 1-2 h at age 4: 2.59; 95 % CI 1.59-4.22). Video games may have a protective effect on the risk of problematic self-regulatory behavior at ages 3 and 5. Conclusion Longer daily exposure to TV during early childhood (age 4-5) may be associated with subsequent problematic child self-regulatory behavior.

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.

Deadlines at work and sleep quality. Cross-sectional and longitudinal findings among Danish knowledge workers.

PubMed

Rugulies, Reiner; Martin, Marie H T; Garde, Anne Helene; Persson, Roger; Albertsen, Karen

2012-03-01

Exposure to deadlines at work is increasing in several countries and may affect health. We aimed to investigate cross-sectional and longitudinal associations between frequency of difficult deadlines at work and sleep quality. Study participants were knowledge workers, drawn from a representative sample of Danish employees who responded to a baseline questionnaire in 2006 (n = 363) and a follow-up questionnaire in 2007 (n = 302). Frequency of difficult deadlines was measured by self-report and categorized into low, intermediate, and high. Sleep quality was measured with a Total Sleep Quality Score and two indexes (Awakening Index and Disturbed Sleep Index) derived from the Karolinska Sleep Questionnaire. Analyses on the association between frequency of deadlines and sleep quality scores were conducted with multiple linear regression models, adjusted for potential confounders. In addition, we used multiple logistic regression models to analyze whether frequency of deadlines at baseline predicted caseness of sleep problems at follow-up among participants free of sleep problems at baseline. Frequent deadlines were cross-sectionally and longitudinally associated with poorer sleep quality on all three sleep quality measures. Associations in the longitudinal analyses were greatly attenuated when we adjusted for baseline sleep quality. The logistic regression analyses showed that frequent deadlines at baseline were associated with elevated odds ratios for caseness of sleep problems at follow-up, however, confidence intervals were wide in these analyses. Frequent deadlines at work were associated with poorer sleep quality among Danish knowledge workers. We recommend investigating the relation between deadlines and health endpoints in large-scale epidemiologic studies. Copyright © 2011 Wiley Periodicals, Inc.

Equatorial Plasma Bubbles: Effect of Thermospheric Winds Modulated by DE3 Tidal Waves

NASA Astrophysics Data System (ADS)

Sidorova, L. N.; Filippov, S. V.

2018-03-01

A hypothesis about the effect of the tropospheric source on the longitudinal distributions of the equatorial plasma bubbles observed in the topside ionosphere was proposed earlier. It was supposed that this influence is transferred mainly by the thermospheric winds modulated by the DE3 tropospheric tidal waves. This conclusion was based on the discovered high degree correlation ( R ≅ 0.79) between the variations of the longitudinal distribution of the plasma bubbles and the neutral atmospheric density. In this work, the hypothesis of the effect of the thermospheric tidal waves on the plasma bubbles at the stage of their generation is subjected to further verification. With this purpose, the longitudinal distributions of the frequency of the plasma bubble observations at the different ionospheric altitudes ( 600 km, ROCSAT-1; 1100 km, ISS-b) are analyzed; their principal similarity is revealed. Comparative analysis of these distributions with the longitudinal profile of the deviations of the zonal thermospheric wind ( 400 km, CHAMP) modulated by the DE3 tidal wave is carried out; their considerable correlation ( R ≅ 0.69) is revealed. We conclude that the longitudinal variations of the zonal wind associated with DE3 tidal waves can effect the longitudinal variations in the appearance frequency of the initial "seeding" perturbations, which further evolve into the plasma bubbles.

Perception Accuracy of Affiliative Relationships in Elementary School Children and Young Adolescents

PubMed Central

Daniel, João R.; Silva, Rita R.; Santos, António J.; Cardoso, Jordana; Coelho, Leandra; Freitas, Miguel; Ribeiro, Olívia

2017-01-01

There has been a rapid growth of studies focused on selection and socialization processes of peer groups, mostly due to the development of stochastic actor-based models to analyze longitudinal social network data. One of the core assumptions of these models is that individuals have an accurate knowledge of the dyadic relationships within their network (i.e., who is and is not connected to whom). Recent cross-sectional findings suggest that elementary school children are very inaccurate in perceiving their classmates’ dyadic relationships. These findings question the validity of stochastic actor-based models to study the developmental dynamics of children and carry implications for future research as well as for the interpretation of past findings. The goal of the present study was thus to further explore the adequacy of the accuracy assumption, analysing data from three longitudinal samples of different age groups (elementary school children and adolescents). Our results support the validity of stochastic actor-based models to study the network of adolescents and suggest that the violation of the accuracy assumption for elementary school children is not as severe as previously thought. PMID:29163310

Longitudinal Association Between Physical Activity and Body Fat During Adolescence: A Systematic Review.

PubMed

Ramires, Virgílio Viana; Dumith, Samuel Carvalho; Gonçalves, Helen

2015-09-01

Physical activity (PA) practice has been inversely associated to body fat (BF) and recommended as a way to reduce and prevent obesity. The objective of this study was to conduct a systematic review on the association of PA and BF in adolescence. The review includes 18 longitudinal studies found in the PubMed database, comprising papers published from January 1990 to July 2014. Studies assessing BF only through body mass index were excluded. Among the outcomes analyzed, waist circumference, skinfolds, and absolute and relative fat mass measurement were identified. Questionnaires were the more predominant way to evaluate PA. Most studies showed that PA promotes a protective effect against a higher BF gain. It was concluded that PA has a protective effect against BF with differences between the genders and according to the BF marker or measurement assessed; higher intensity PA leads to a greater effect against BF gain in both genders; and the maintenance or increase of PA level on BF observed through analysis of change in PA level yielded more consistent findings in the relation between PA and BF.

The impact of running away on teen girls' sexual health.

PubMed

Lacoursiere, Terri; Fontenot, Holly B

2012-01-01

This article reviews three recent studies investigating the impact of running away on adolescent females' sexual health. There are between 500,000 and 2.8 million runaway and homeless youth in the U.S. at any point in time, and adolescent females are at increased risk as compared to males. All three studies analyzed data from The National Longitudinal Study of Adolescent Health and each examined a different health risk related to runaways including sexual debut, sexual assault and pregnancy. These studies show how health risks are persistent even after adolescents return home to their primary residence. © 2012 AWHONN.

Longitudinal Neuroimaging Hippocampal Markers for Diagnosing Alzheimer's Disease.

PubMed

Platero, Carlos; Lin, Lin; Tobar, M Carmen

2018-05-21

Hippocampal atrophy measures from magnetic resonance imaging (MRI) are powerful tools for monitoring Alzheimer's disease (AD) progression. In this paper, we introduce a longitudinal image analysis framework based on robust registration and simultaneous hippocampal segmentation and longitudinal marker classification of brain MRI of an arbitrary number of time points. The framework comprises two innovative parts: a longitudinal segmentation and a longitudinal classification step. The results show that both steps of the longitudinal pipeline improved the reliability and the accuracy of the discrimination between clinical groups. We introduce a novel approach to the joint segmentation of the hippocampus across multiple time points; this approach is based on graph cuts of longitudinal MRI scans with constraints on hippocampal atrophy and supported by atlases. Furthermore, we use linear mixed effect (LME) modeling for differential diagnosis between clinical groups. The classifiers are trained from the average residue between the longitudinal marker of the subjects and the LME model. In our experiments, we analyzed MRI-derived longitudinal hippocampal markers from two publicly available datasets (Alzheimer's Disease Neuroimaging Initiative, ADNI and Minimal Interval Resonance Imaging in Alzheimer's Disease, MIRIAD). In test/retest reliability experiments, the proposed method yielded lower volume errors and significantly higher dice overlaps than the cross-sectional approach (volume errors: 1.55% vs 0.8%; dice overlaps: 0.945 vs 0.975). To diagnose AD, the discrimination ability of our proposal gave an area under the receiver operating characteristic (ROC) curve (AUC) [Formula: see text] 0.947 for the control vs AD, AUC [Formula: see text] 0.720 for mild cognitive impairment (MCI) vs AD, and AUC [Formula: see text] 0.805 for the control vs MCI.

Longitudinal Relationship Between Loneliness and Social Isolation in Older Adults: Results From the Cardiovascular Health Study.

PubMed

Petersen, Johanna; Kaye, Jeffrey; Jacobs, Peter G; Quinones, Ana; Dodge, Hiroko; Arnold, Alice; Thielke, Stephen

2016-08-01

To understand the longitudinal relationship between loneliness and isolation. Participants included 5,870 adults 65 years and older (M = 72.89 ± 5.59 years) from the first 5 years of the Cardiovascular Health Study. Loneliness was assessed using a dichotomized loneliness question. Social isolation was assessed using six items from the Lubben Social Network Scale. Yearly life events were included to assess abrupt social network changes. Mixed effects logistic regression was employed to analyze the relationship between isolation and loneliness. Higher levels of social isolation were associated with higher odds of loneliness, as was an increase (from median) in level of social isolation. Life events such as a friend dying were also associated with increased odds of loneliness. These results suggest that average level of isolation and increases in the level of isolation are closely tied to loneliness, which has implications for future assessment or monitoring of loneliness in older adult populations. © The Author(s) 2015.

Cycle of Violence in Schools: Longitudinal Reciprocal Relationship Between Student's Aggression and Teacher's Use of Corporal Punishment.

PubMed

Choi, Boungho

2017-11-01

The purpose of this study is to examine the longitudinal reciprocal relationship between student's aggression and teacher's use of corporal punishment. An autoregressive cross-lagged model was analyzed with the data drawn from 4,051 Korean secondary students (male = 2,084, female = 1,967), in Gyeonggi Education Panel Study for three waves (seventh-ninth grades). Results revealed that student's aggression provoke teacher's use of corporal punishment and also teacher's use of corporal punishment provokes student's aggression. It is important in that it suggests the cycle of violence with the reciprocal relationship between student's aggression and teacher's use of corporal punishment, rather than positing the unidirectional effects. Practically, teachers should keep in mind that corporal punishments, which are at least partially attributable to student's aggression, actually worsen the problem and lead to a cycle of violence in schools. Accordingly, they should instead respond with alternative disciplinary strategies or direct interventions dealing with the causes of aggression.

Accounting for Posttraumatic Stress Disorder Symptom Severity With Pre- and Posttrauma Measures: A Longitudinal Study of Older Adults.

PubMed

Ogle, Christin M; Rubin, David C; Siegler, Ilene C

2016-03-01

Using data from a longitudinal study of community-dwelling older adults, we analyzed the most extensive set of known correlates of PTSD symptoms obtained from a single sample to examine the measures' independent and combined utility in accounting for PTSD symptom severity. Fifteen measures identified as PTSD risk factors in published meta-analyses and 12 theoretically and empirically supported individual difference and health-related measures were included. Individual difference measures assessed after the trauma, including insecure attachment and factors related to the current trauma memory, such as self-rated severity, event centrality, frequency of involuntary recall, and physical reactions to the memory, accounted for symptom severity better than measures of pre-trauma factors. In an analysis restricted to prospective measures assessed before the trauma, the total variance explained decreased from 56% to 16%. Results support a model of PTSD in which characteristics of the current trauma memory promote the development and maintenance of PTSD symptoms.

Generalization of the van der Pauw Method: Analyzing Longitudinal Magnetoresistance Asymmetry to Quantify Doping Gradients

NASA Astrophysics Data System (ADS)

Grayson, M.; Zhou, Wang; Yoo, Heun-Mo; Prabhu-Gaunkar, S.; Tiemann, L.; Reichl, C.; Wegscheider, W.

A longitudinal magnetoresistance asymmetry (LMA) between a positive and negative magnetic field is known to occur in both the extreme quantum limit and the classical Drude limit in samples with a nonuniform doping density. By analyzing the current stream function in van der Pauw measurement geometry, it is shown that the electron density gradient can be quantitatively deduced from this LMA in the Drude regime. Results agree with gradients interpolated from local densities calibrated across an entire wafer, establishing a generalization of the van der Pauw method to quantify density gradients. Results will be shown of various semoconductor systems where this method is applied, from bulk doped semiconductors, to exfoliated 2D materials. McCormick Catalyst Award from Northwestern University, EECS Bridge Funding, and AFOSR FA9550-15-1-0247.

The education of scientists: Gender differences during the early life course

NASA Astrophysics Data System (ADS)

Shauman, Kimberlee Akin

In this dissertation, I examine gender differences in the science and engineering (S/E) educational trajectory--the pre-college and college experiences that lead to specialized education and qualification for an S/E occupation. This research makes important contributions by providing detailed and updated information about gender differences in the timing and causal mechanisms for flows into and out of the S/E educational trajectory. By using longitudinal data to model the linkages between past and future science experiences, I measure the dynamic process underlying the S/E educational trajectory and challenge the predominant "science pipeline" conceptualization of this process. I use the life course perspective as a guide to conceptualizing the S/E trajectory and to analyzing the social forces that shape the educational and career goals of individual women and men. I develop a conceptual model that specifies how the effects of a set of social influences gradually shift in measurable and predictable ways over the educational "life histories" of individuals. The causal factors in the model are (1) individual influences such as ability and attitudes, (2) familial influences, and (3) the influence of significant others in the social structure. To uncover gender differences in the process of becoming a scientist, I use four nationally representative longitudinal studies: the National Education Longitudinal Study of 1988, the Longitudinal Study of American Youth, the High School and Beyond, and the National Longitudinal Study of the Class of 1972. The empirical analyses of this dissertation focus on the individual and familial influences on participation in the S/E educational trajectory. Past experience in S/E education increases the likelihood of future participation, but persistence in the S/E trajectory is not the only viable route to S/E degree attainment. Entry into S/E majors during college is common, and it is a prevalent path to an S/E bachelor's degree, especially for women. The transition from high school to college is the point where the educational paths of males and females diverge significantly. Expectations about future family roles have the greatest influence on the gender differences in the patterns of participation in the S/E educational trajectory.

Adverse Left Ventricular Remodeling and Age Assessed with Cardiac MR Imaging: The Multi-Ethnic Study of Atherosclerosis

PubMed Central

McClelland, Robyn L.; Gomes, Antoinette S.; Hundley, W. Gregory; Cheng, Susan; Wu, Colin O.; Carr, J. Jeffrey; Shea, Steven; Bluemke, David A.; Lima, Joao A. C.

2016-01-01

Purpose To evaluate age-related left ventricular (LV) remodeling during longitudinal observation of a large cohort of asymptomatic individuals who were free of clinical cardiovascular disease at baseline. Materials and Methods The applicable institutional review boards approved this study, and all participants gave informed consent. Cardiac magnetic resonance (MR) imaging was used to identify longitudinal changes in LV structure and function in 2935 participants who underwent baseline and follow-up cardiac MR imaging in the Multi-Ethnic Study of Atherosclerosis. Participants were free of clinical cardiovascular disease at baseline. Participants who experienced an incident coronary heart disease event were excluded. Data were analyzed with multivariable mixed-effects regression models in which the outcome was cardiac MR imaging measurement, and the covariates included follow-up time and cardiac risk factors. Results Participants were aged 54–94 years at follow-up, and 53% of the participants were women. Median time between baseline and follow-up cardiac MR imaging was 9.4 years. Over this period, LV mass increased in men and decreased slightly in women (8.0 and −1.6 g per decade, respectively; P < .001). In both men and women, LV end-diastolic volume decreased (−9.8 and −13.3 mL per decade, respectively; P < .001), stroke volume decreased (−8.8 and −8.6 mL per decade, respectively; P < .001), and mass-to-volume ratio increased (0.14 and 0.11 g/mL per decade, respectively; P < .001). Change in LV mass was positively associated with systolic blood pressure and body mass index and negatively associated with treated hypertension and high-density lipoprotein cholesterol level. In men, the longitudinal LV mass increase was in contrast to a cross-sectional pattern of LV mass decrease. Conclusion As patients age, the LV responds differently in its mass and volume between men and women, although both men and women experience increased concentric LV remodeling with age. In men, the opposition of longitudinal and cross-sectional changes in LV mass highlights the importance of longitudinal study. © RSNA, 2015 Online supplemental material is available for this article. PMID:26485617

Evaluation of vocal fold vibration with an assessment form for high-speed digital imaging: comparative study between healthy young and elderly subjects.

PubMed

Yamauchi, Akihito; Imagawa, Hiroshi; Yokonishi, Hisayuki; Nito, Takaharu; Yamasoba, Tatsuya; Goto, Takao; Takano, Shingo; Sakakibara, Ken-Ichi; Tayama, Niro

2012-11-01

We conducted a prospective study with a subjective assessment form for high-speed digital imaging (HSDI) to elucidate the features of vocal fold vibrations in vocally healthy subjects and to clarify gender- and age-related differences. Healthy adult volunteers participated in this study. They were divided into young (aged 35 and younger) and elderly (aged 65 and older) groups, and the scores of an assessment form for HSDI characteristics elaborated at our institution were statistically analyzed. Twenty-six young subjects (males: 9, females: 17; mean age: 27 years) and 20 elderly subjects (males: 8, females: 12; mean age: 72 years) were assigned to our study. Posterior gap and posterior-to-anterior longitudinal phase difference were characteristic to young females, whereas in young males, mucosal wave, anterior-to-posterior longitudinal phase difference, and supraglottic hyperactivity were frequent. In elderly males, axis shift, asymmetry, supraglottic hyperactivity, increased mucosal wave, lateral phase difference, and anterior-to-posterior longitudinal phase difference were frequent; and in elderly females, high incidence of lateral phase difference, atrophic change, anterior gap, and asymmetry were observed. The results show that the behaviors of vocal fold vibrations were diverse even in healthy subjects with no vocal complaints or history of laryngeal diseases, and hence, the diversity of vocal fold vibrations in normal subjects must be taken into account in evaluating vocal fold vibrations. Copyright © 2012 The Voice Foundation. Published by Mosby, Inc. All rights reserved.

Right Ventricular Longitudinal Strain Is Depressed in a Bovine Model of Pulmonary Hypertension.

PubMed

Bartels, Karsten; Brown, R Dale; Fox, Daniel L; Bull, Todd M; Neary, Joseph M; Dorosz, Jennifer L; Fonseca, Brian M; Stenmark, Kurt R

2016-05-01

Pulmonary hypertension and resulting right ventricular (RV) dysfunction are associated with significant perioperative morbidity and mortality. Although echocardiography permits real-time, noninvasive assessment of RV function, objective and comparative measures are underdeveloped, and appropriate animal models to study their utility are lacking. Longitudinal strain analysis is a novel echocardiographic method to quantify RV performance. Herein, we hypothesized that peak RV longitudinal strain would worsen in a bovine model of pulmonary hypertension compared with control animals. Newborn Holstein calves were randomly chosen for induction of pulmonary hypertension versus control conditions. Pulmonary hypertension was induced by exposing animals to 14 days of hypoxia (equivalent to 4570 m above sea level or 430 mm Hg barometric pressure). Control animals were kept at ambient pressure/normoxia. At the end of the intervention, transthoracic echocardiography was performed in awake calves. Longitudinal wall strain was analyzed from modified apical 4-chamber views focused on the RV. Comparisons between measurements in hypoxic versus nonhypoxic conditions were performed using Student t test for independent samples and unequal variances. After 14 days at normoxic versus hypoxic conditions, 15 calves were examined with echocardiography. Pulmonary hypertension was confirmed by right heart catheterization and associated with reduced RV systolic function. Mean systolic strain measurements were compared in normoxia-exposed animals (n = 8) and hypoxia-exposed animals (n = 7). Peak global systolic longitudinal RV strain after hypoxia worsened compared to normoxia (-10.5% vs -16.1%, P = 0.0031). Peak RV free wall strain also worsened after hypoxia compared to normoxia (-9.6% vs -17.3%, P = 0.0031). Findings from strain analysis were confirmed by measurement of tricuspid annular peak systolic excursion. Peak longitudinal RV strain detected worsened RV function in animals with hypoxia-induced pulmonary hypertension compared with control animals. This relationship was demonstrated in the transthoracic echocardiographic 4-chamber view independently for the RV free wall and for the combination of the free and septal walls. This innovative model of bovine pulmonary hypertension may prove useful to compare different monitoring technologies for the assessment of early events of RV dysfunction. Further studies linking novel RV imaging applications with mechanistic and therapeutic approaches are needed.

Methodological issues underlying multiple decrement life table analysis.

PubMed

Mode, C J; Avery, R C; Littman, G S; Potter, R G

1977-02-01

In this paper, the actuarial method of multiple decrement life table analysis of censored, longitudinal data is examined. The discussion is organized in terms of the first segment of usage of an intrauterine device. Weaknesses of the actuarial approach are pointed out, and an alternative approach, based on the classical model of competing risks, is proposed. Finally, the actuarial and the alternative method of analyzing censored data are compared, using data from the Taichung Medical Study on Intrauterine Devices.

Axial energy spread measurements of an accelerated positive ion beam

NASA Astrophysics Data System (ADS)

Lee, Y.; Gough, R. A.; Kunkel, W. B.; Leung, K. N.; Perkins, L. T.; Pickard, D. S.; Sun, L.; Vujic, J.; Williams, M. D.; Wutte, D.; Mondelli, Alfred A.; Stengl, Gerhard

1997-01-01

A multicusp ion source has been designed for use in ion projection lithography. Longitudinal energy spreads of the extracted positive hydrogen ion beam have been studied using a retarding field energy analyzer. It has been found that the filament-discharge multicusp ion source can deliver a beam with an energy spread less than 3 eV which is required for the ALG-1000 machine. The multicusp ion source can also deliver the current required for the application.

The Effects on Muscle Activation of Flatfoot during Gait According to the Velocity on an Ascending Slope.

PubMed

Lee, Chang-Ryeol; Kim, Myoung-Kwon

2014-05-01

[Purpose] This study determined the difference between flatfeet and normal feet in humans on an ascending slope using electromyography (EMG). [Subjects] This study was conducted on 30 adults having normal feet (n=15) and flatfeet (n=15), all of whom were 21 to 30 years old. [Methods] A treadmill (AC5000M, SCIFIT,) was used to analyze kinematic features during gait. These features were analyzed at slow, normal, and fast gait velocities on an ascending slope. A surface electromyogram (TeleMyo 2400T, Noraxon Co., USA) was used to measure muscle activity changes. [Results] The activities of most muscles in the subjects with flatfeet were significantly different from the muscle activities in the subjects with normal feet at different gait velocities on an ascending slope. There were significant differences in the vastus medialis and abductor hallucis muscles. [Conclusion] Because muscle activation of the vastus medialis in relation to stability of the lower extremity has a tendency to increase with an increase in gait velocity on an ascending slope, we hypothesized that higher impact transfer to the knee joints occurs in subjects with flatfeet due to the lack of a medial longitudinal arch and that the abductor halluces muscles, which provide dynamic stability to the medial longitudinal arches, do not activate well when they are needed in subjects with flatfeet.

How can Academic Context Variables Contribute to the Personal Well-Being of Higher Education Students?

PubMed

Figueira, Célia Palma; Marques-Pinto, Alexandra; Pereira, Cicero Roberto; Roberto, Magda Sofia

2017-10-11

This study analyzed the influence of perceived time pressure, role clarity, working conditions and peer social support on the personal well-being (subjective, psychological and social well-being) of higher education students, in a sample of 128 Portuguese students from the University of Lisbon. A model was proposed which predicts a negative influence of time pressure and a positive influence of role clarity, working conditions and peer social support on students' personal well-being, throughout the academic year. Data was collected by means of a longitudinal design, at the beginning and end of the academic year, through self-report questionnaires. Structural equation models were used to analyze cross-sectional and cross-lagged relations among the variables. At cross-sectional level, results revealed a good fit to data (CFI = .928; IFI = .931; RMSEA = .060) illustrating that the perception of academic context variables was related to well-being dimensions. At longitudinal level, however, cross-lagged models did not fit so well to the data (CFI = .863; IFI = .869; RMSEA = .058) with both perceptions of time pressure (β = .167; p = .037) and role clarity (β = -.288; p = .031) significantly predicting well-being, but not in the expected direction, encouraging the accomplishment of studies to further a broader understanding of higher education students' well-being and its predictors. Implications for higher education scholars and practitioners and suggestions for future research are discussed.

Accuracy of a Rapid Diagnostic Test (Cypress Chagas Quick Test®) for the Diagnosis of Chronic Chagas Disease in a Nonendemic Area: A Retrospective Longitudinal Study.

PubMed

Angheben, Andrea; Staffolani, Silvia; Anselmi, Mariella; Tais, Stefano; Degani, Monica; Gobbi, Federico; Buonfrate, Dora; Gobbo, Maria; Bisoffi, Zeno

2017-11-01

We analyzed the accuracy of Chagas Quick Test ® , a rapid diagnostic test, for the diagnosis of chronic Chagas disease through a retrospective study on a cohort of 669 patients consecutively examined at a single reference center in Italy, during a 7-year period. We observed high concordance with serological reference standard but low accuracy for screening purposes (sensitivity/specificity: 82.8%/98.7%) at least in our nonendemic context.

Maternal sensitivity and effortful control in early childhood as predictors of adolescents' adjustment: The mediating roles of peer group affiliation and social behaviors.

PubMed

Laible, Deborah; Carlo, Gustavo; Davis, Alexandra N; Karahuta, Erin

2016-06-01

Longitudinal links between early childhood temperament, maternal sensitivity, and adolescents' adjustment have been proposed and found in several longitudinal studies, but the mechanisms of influence have not been explored. The authors examined the paths from maternal sensitivity and temperament in early childhood to adolescents' prosocial, aggressive, and delinquent behaviors via childhood social behaviors and peer group affiliation. Data at 54 months, Grade 3 (M age = 9.03, SD = .31), Grade 6 (M age = 11.95, SD = .34), and Grade 9 (M age = 15.57, SD = .78) from the NICHD SECCYD longitudinal investigation of 1,364 participants (52% boys) was analyzed. Overall, results yielded evidence that maternal sensitivity and child temperament at 54 months of age predicted prosocial, aggressive, and delinquent outcomes at age 15. Affiliation with peer groups (especially with prosocial peers) and social behaviors in childhood mediated the aforementioned paths for effortful control, but not for maternal sensitivity. Discussion focuses on the implications for understanding the long-term effects of early childhood predictors on behavioral outcomes in adolescence. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Histologic anatomy of the lesser metatarsophalangeal joint plantar plate.

PubMed

Gregg, J; Marks, P; Silberstein, M; Schneider, T; Kerr, J

2007-03-01

The plantar plate is the fibrocartilaginous structure that supports the ball of the foot, withstanding considerable compressive and tensile forces. This study describes the morphology of the plantar plate in order to understand its function and the pathologic disorders associated with it. Eight lesser metatarsophalangeal joint plantar plates from three soft-embalmed cadavers (74-92 years, two males, one female), and eight lesser metatarsophalangeal joint plantar plates from a fresh cadaver (19-year-old male) were obtained for histology assessment. Paraffin sections (10 microm) in the longitudinal and transverse planes were analyzed with bright-field and polarized light microscopy. The central plantar plate collagen bundles run in the longitudinal plane with varying degrees of undulation. The plantar plate borders run transversely and merge with collateral ligaments and the deep transverse intermetatarsal ligament. Bright-field microscopic evaluation shows the plantar aspect of the plantar plate becomes ligament-like the further distally it tapers, containing fewer chondrocytes, and a greater abundance of fibroblasts. The enthesis reveals longitudinal and interwoven collagen bundles entering the proximal phalanx with multiple interdigitations. Longer interdigitations centrally compared to the dorsal and plantar aspects suggest that the central fibers experience the greatest loads.

Developmental trajectories and longitudinal mediation effects of self-esteem, peer attachment, child maltreatment and depression on early adolescents.

PubMed

Ju, Soyoung; Lee, Yanghee

2018-02-01

The purpose of this study is to identify the developmental trajectories of peer attachment, self-esteem, depression, and child maltreatment, and to understand the longitudinal mediation effects that peer attachment and self-esteem have on the influence of perceived abuse on early adolescent depression. This study uses Year 1 to Year 5 data of the 4th grader panel of the Korea Youth Panel Survey (KYPS) and utilizes a multivariate latent growth model to analyze the main variables in the applicable data between 5th (i.e., Year 2) and 8th (i.e., Year 5) grades. The results indicate that from the 5th to the 8th grade, the degree of abuse and depression increases while self-esteem gradually decreases with slowly lowering peer attachment. A significant distribution of the initial values and the rate of change were present for all main variables of the study, confirming individual differences in time wise changes. Further, more exposure to abuse correlated with a decrease in self-esteem, while an increase in self-esteem greatly reduced depression. The initial value of self-esteem showed a partial mediation effect, whereas the rate of change indicated a full mediation effect with a significant longitudinal mediation effect. More experience of abuse during early adolescence indicated a lower degree of peer attachment, and a higher peer attachment was related to decreased depression. A significant partial mediation effect was present for both the initial value and the rate of change of peer attachment, and a longitudinal mediation effect was present. This study confirmed that self-esteem in early adolescents is an important protective factor that can greatly reduce the degree of depression, and suggests continuous interventions conducted to increase self-esteem in adolescence. Furthermore, by determining that peer attachment decreases the degree of depression in children at risk, the study emphasizes the healing aspect of adolescent peer attachment. Copyright © 2017 Elsevier Ltd. All rights reserved.

Genetic and Environmental Regulation on Longitudinal Change of Metabolic Phenotypes in Danish and Chinese Adult Twins

PubMed Central

Li, Shuxia; Kyvik, Kirsten Ohm; Pang, Zengchang; Zhang, Dongfeng; Duan, Haiping; Tan, Qihua; Hjelmborg, Jacob; Kruse, Torben; Dalgård, Christine

2016-01-01

Objective The rate of change in metabolic phenotypes can be highly indicative of metabolic disorders and disorder-related modifications. We analyzed data from longitudinal twin studies on multiple metabolic phenotypes in Danish and Chinese twins representing two populations of distinct ethnic, cultural, social-economic backgrounds and geographical environments. Materials and Methods The study covered a relatively large sample of 502 pairs of Danish adult twins followed up for a long period of 12 years with a mean age at intake of 38 years (range: 18–65) and a total of 181 Chinese adult twin pairs traced for about 7 years with a mean baseline age of 39.5 years (range: 23–64). The classical twin models were fitted to the longitudinal change in each phenotype (Δphenotype) to estimate the genetic and environmental contributions to the variation in Δphenotype. Results Moderate to high contributions by the unique environment were estimated for all phenotypes in both Danish (from 0.51 for low density lipoprotein cholesterol up to 0.72 for triglycerides) and Chinese (from 0.41 for triglycerides up to 0.73 for diastolic blood pressure) twins; low to moderate genetic components were estimated for long-term change in most of the phenotypes in Danish twins except for triglycerides and hip circumference. Compared with Danish twins, the Chinese twins tended to have higher genetic control over the longitudinal changes in lipids (except high density lipoprotein cholesterol) and glucose, higher unique environmental contribution to blood pressure but no genetic contribution to longitudinal change in body mass traits. Conclusion Our results emphasize the major contribution of unique environment to the observed intra-individual variation in all metabolic phenotypes in both samples, and meanwhile reveal differential patterns of genetic and common environmental regulation on changes over time in metabolic phenotypes across the two samples. PMID:26862898

Otoacoustic emissions versus audiometry in monitoring hearing loss after long-term noise exposure - a systematic review.

PubMed

Helleman, Hiske W; Eising, Hilde; Limpens, Jacqueline; Dreschler, Wouter A

2018-03-15

Objectives The objective of this systematic review was to compare otoacoustic emissions (OAE) with audiometry in their effectiveness to monitor effects of long-term noise exposure on hearing. Methods We conducted a systematic search of MEDLINE, Embase and the non-MEDLINE subset of PubMed up to March 2016 to identify longitudinal studies on effects of noise exposure on hearing as determined by both audiometry and OAE. Results This review comprised 13 articles, with 30-350 subjects in the longitudinal analysis. A meta-analysis could not be performed because the studies were very heterogeneous in terms of measurement paradigms, follow-up time, age of included subjects, inclusion of data points, outcome parameters and method of analysis. Overall there seemed to be small changes in both audiometry and OAE over time. Individual shifts were detected by both methods but a congruent pattern could not be observed. Some studies found that initial abnormal or low-level emissions might predict future hearing loss but at the cost of low specificity due to a high number of false positives. Other studies could not find such predictive value. Conclusions The reported heterogeneity in the studies calls for more uniformity in including, reporting and analyzing longitudinal data for audiometry and OAE. For the overall results, both methods showed small changes from baseline towards a deterioration in hearing. OAE could not reliably detect threshold shifts at individual level. With respect to the predictive value of OAE, the evidence was not conclusive and studies were not in agreement. The reported predictors had low specificity.

Physical mechanisms of longitudinal vortexes formation, appearance of zones with high heat fluxes and early transition in hypersonic flow over delta wing with blunted leading edges

NASA Astrophysics Data System (ADS)

Alexandrov, S. V.; Vaganov, A. V.; Shalaev, V. I.

2016-10-01

Processes of vortex structures formation and they interactions with the boundary layer in the hypersonic flow over delta wing with blunted leading edges are analyzed on the base of experimental investigations and numerical solutions of Navier-Stokes equations. Physical mechanisms of longitudinal vortexes formation, appearance of abnormal zones with high heat fluxes and early laminar turbulent transition are studied. These phenomena were observed in many high-speed wind tunnel experiments; however they were understood only using the detailed analysis of numerical modeling results with the high resolution. Presented results allowed explaining experimental phenomena. ANSYS CFX code (the DAFE MIPT license) on the grid with 50 million nodes was used for the numerical modeling. The numerical method was verified by comparison calculated heat flux distributions on the wing surface with experimental data.

Direct measurement of the effective infrared dielectric response of a highly doped semiconductor metamaterial.

PubMed

Al Mohtar, Abeer; Kazan, Michel; Taliercio, Thierry; Cerutti, Laurent; Blaize, Sylvain; Bruyant, Aurélien

2017-03-24

We have investigated the effective dielectric response of a subwavelength grating made of highly doped semiconductors (HDS) excited in reflection, using numerical simulations and spectroscopic measurement. The studied system can exhibit strong localized surface resonances and has, therefore, a great potential for surface-enhanced infrared absorption (SEIRA) spectroscopy application. It consists of a highly doped InAsSb grating deposited on lattice-matched GaSb. The numerical analysis demonstrated that the resonance frequencies can be inferred from the dielectric function of an equivalent homogeneous slab by accounting for the complex reflectivity of the composite layer. Fourier transform infrared reflectivity (FTIR) measurements, analyzed with the Kramers-Kronig conversion technique, were used to deduce the effective response in reflection of the investigated system. From the knowledge of this phenomenological dielectric function, transversal and longitudinal energy-loss functions were extracted and attributed to transverse and longitudinal resonance modes frequencies.

Modified screening interaction potential on dust lattice waves in dusty plasma ring

NASA Astrophysics Data System (ADS)

He, Kerong; Chen, Hui; Liu, Sanqiu

2017-05-01

In the present paper, the modified screening interaction potential was adopted to investigate the dust lattice waves in dusty ring. Firstly, the influence of parameter ε on the modified screening interaction potential was analyzed; and it was found that the parameter ε has a long-range effect on the pairwise interaction between the particles. Secondly, the dispersion relations of longitudinal and transverse waves are obtained, and the effect of long-range action parameter ε, dimensionless lattice parameter α and dimensionless shielding parameter \\tilde{κ } on the dust lattice waves propagation in dusty ring are studied. Some interesting phenomena, such as the coupling of longitudinal and transverse waves, and instabilities of transverse waves are found, which are in good agreement with some previous works. Finally, the transverse wave instabilities and the relevant critical lattice parameter αc are presented and discussed.

Experimental studies of transonic flow field near a longitudinally slotted wind tunnel wall. Ph.D. Thesis - George Washington Univ., 1988

NASA Technical Reports Server (NTRS)

Everhart, Joel L.; Bobbitt, Percy J.

1994-01-01

The results of detailed parametric experiments are presented for the near-wall flow field of a longitudinally slotted transonic wind tunnel. Existing data are reevaluated and new data obtained in the Langley 6- by 19-inch Transonic Wind Tunnel are presented and analyzed. In the experiments, researchers systematically investigate many pertinent wall-geometry variables such as the wall openness and the number of slots along with the free stream Mach number and model angle of attack. Flow field surveys on the plane passing through the centerline of the slot were conducted and are presented. The effects of viscosity on the slot flow are considered in the analysis. The present experiments, combined with those of previous investigations, give a more complete physical characterization of the flow near and through the slotted wall of a transonic wind tunnel.

Transverse momentum dependent two-pion Bose-Einstein correlations in Au + Au collisions at 11.6 A (center-dot) GeV/c

NASA Technical Reports Server (NTRS)

Lee, J. H.

1998-01-01

Bose-Einstein correlations of (pi)(sup +)(pi)(sup +) and (pi)(sup -) (pi)(sup -) pairs collected by the BNL-E866 Forward Spectrometer in 11.6 A(center-dot)GeV/c Au + Au collisions have been measured. The data were analyzed using three-dimensional correlation functions parameterized by the Yano-Koonin-Potgoretskii and Bertsch-Pratt formalism to study transverse momentum dependent source parameters. Rapid decreases of longitudinal source radii and slower decreases in the transverse parameters with increasing transverse momentum were observed, which suggests a strong longitudinal and some transverse expansion. A freeze-out time (tau)(sub 0) was derived as 4.5--5 fm/c, under the assumption of the freeze-out temperature T = 130 MeV, and the duration of emission was found to be (delta)(tau) (approx) 2--4 fm/c.

Temporal Stability of the Human Skin Microbiome.

PubMed

Oh, Julia; Byrd, Allyson L; Park, Morgan; Kong, Heidi H; Segre, Julia A

2016-05-05

Biogeography and individuality shape the structural and functional composition of the human skin microbiome. To explore these factors' contribution to skin microbial community stability, we generated metagenomic sequence data from longitudinal samples collected over months and years. Analyzing these samples using a multi-kingdom, reference-based approach, we found that despite the skin's exposure to the external environment, its bacterial, fungal, and viral communities were largely stable over time. Site, individuality, and phylogeny were all determinants of stability. Foot sites exhibited the most variability; individuals differed in stability; and transience was a particular characteristic of eukaryotic viruses, which showed little site-specificity in colonization. Strain and single-nucleotide variant-level analysis showed that individuals maintain, rather than reacquire, prevalent microbes from the environment. Longitudinal stability of skin microbial communities generates hypotheses about colonization resistance and empowers clinical studies exploring alterations observed in disease states. Copyright © 2016 Elsevier Inc. All rights reserved.