Examining Procrastination Across Multiple Goal Stages: A Longitudinal Study of Temporal Motivation Theory

Directory of Open Access Journals (Sweden)

Piers Steel

2018-04-01

Full Text Available Procrastination is among the most common of motivational failures, putting off despite expecting to be worse off. We examine this dynamic phenomenon in a detailed and realistic longitudinal design (Study 1 as well as in a large correlational data set (N = 7400; Study 2. The results are largely consistent with temporal motivation theory. People’s pacing style reflects a hyperbolic curve, with the steepness of the curve predicted by self-reported procrastination. Procrastination is related to intention-action gaps, but not intentions. Procrastinators are susceptible to proximity of temptation and to the temporal separation between their intention and the planned act; the more distal, the greater the gap. Critical self-regulatory skills in explaining procrastination are attention control, energy regulation and automaticity, accounting for 74% of the variance. Future research using this design is recommended, as it provides an almost ideal blend of realism and detailed longitudinal assessment.

Examining Procrastination Across Multiple Goal Stages: A Longitudinal Study of Temporal Motivation Theory.

Science.gov (United States)

Steel, Piers; Svartdal, Frode; Thundiyil, Tomas; Brothen, Thomas

2018-01-01

Procrastination is among the most common of motivational failures, putting off despite expecting to be worse off. We examine this dynamic phenomenon in a detailed and realistic longitudinal design (Study 1) as well as in a large correlational data set ( N = 7400; Study 2). The results are largely consistent with temporal motivation theory. People's pacing style reflects a hyperbolic curve, with the steepness of the curve predicted by self-reported procrastination. Procrastination is related to intention-action gaps, but not intentions. Procrastinators are susceptible to proximity of temptation and to the temporal separation between their intention and the planned act; the more distal, the greater the gap. Critical self-regulatory skills in explaining procrastination are attention control, energy regulation and automaticity, accounting for 74% of the variance. Future research using this design is recommended, as it provides an almost ideal blend of realism and detailed longitudinal assessment.

[A school-level longitudinal study of clinical performance examination scores].

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Park, Jang Hee

2015-06-01

This school-level longitudinal study examined 7 years of clinical performance data to determine differences (effects) in students and annual changes within a school and between schools; examine how much their predictors (characteristics) influenced the variation in student performance; and calculate estimates of the schools' initial status and growth. A school-level longitudinal model was tested: level 1 (between students), level 2 (annual change within a school), and level 3 (between schools). The study sample comprised students who belonged to the CPX Consortium (n=5,283 for 2005~2008 and n=4,337 for 2009~2011). Despite a difference between evaluation domains, the performance outcomes were related to individual large-effect differences and small-effect school-level differences. Physical examination, clinical courtesy, and patient education were strongly influenced by the school effect, whereas patient-physician interaction was not affected much. Student scores are influenced by the school effect (differences), and the predictors explain the variation in differences, depending on the evaluation domain.

SAFT and TOFD evaluation for ultrasonic testing of longitudinal welds in large-diameter pipes; SAFT- und TOFD-Auswertung fuer die Ultraschall-Schweissnahtpruefung von laengsnahtgeschweissten Grossrohren

Energy Technology Data Exchange (ETDEWEB)

Rieder, Hans; Dillhoefer, Alexander; Spies, Martin [Fraunhofer-Institut fuer Techno- und Wirtschaftsmathematik ITWM, Kaiserslautern (Germany); Graff, Alfred; Orth, Thomas [Salzgitter Mannesmann Forschung GmbH, Duisburg (Germany); Kersting, Thomas [Europipe GmbH, Muelheim an der Ruhr (Germany). Werk Muelheim

2010-07-01

The authors present a mobile multichannel system for testing of longitudinal welds in large-diameter tubes. The prototype was designed for in situ inspection of longitudinal welds using transversal and longitudinal waves impacting at an angle from both sides in combined SE and IE operation. The reconstruction and imaging software enables SAFT calculations for all surface curves and superposition of the SAFT reconstructions from both sides into a general image of the weld. This includes superposition of the TOFD test data with a suitable evaluation and assessment concept. Details are presented, as are test results on test pieces for validation and on longitudinal welds in large-diameter tubes. (orig.)

The ONS Longitudinal Study--a prestigious past and a bright future.

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Goldring, Shayla; Newman, Jim

2010-01-01

place for analysis.The other ONS LS-based articles and reports in this edition largely focus on research into issues related to families and households, as summarised below: A collaborative project involving Ben Wilson (ONS) and Rachel Stuchbury (CeLSIUS) comparing the stability of partnerships involving marriage and cohabitation.A project looking at transitions in children's experience of living in a workless household and how this varies by ethnic group, submitted by Lucinda Platt (Institute for Social & Economic Research, University of Essex).An article on the effect of a change in the census definition of a child between 1991 and 2001 submitted by Emily Grundy, Rachel Stuchbury and Harriet Young (CeLSIUS).The remainder of this introductory article will focus on the ONS LS, its history and some examples of its use, and gives a summary of planned developments over the coming years. Please refer to the contact details at the end of the article if you require further information on any of the three longitudinal studies.

Longitudinal intensity effects in the CERN Large Hadron Collider

CERN Document Server

AUTHOR|(CDS)2081238; Rivkin, Leonid

This PhD thesis provides an improved knowledge of the LHC longitudinal impedance model and a better understanding of the longitudinal intensity effects. These effects can limit the LHC performance and lead to a reduction of the integrated luminosity. The LHC longitudinal impedance was measured with beams. Results obtained using traditional techniques are consistent with the expectations based on the impedance model, although the measurement precision was proven insufficient for the low impedance of the LHC. Innovative methods to probe the LHC reactive impedance were successfully used. One of the methods is based on exciting the beam with a sinusoidal rf phase modulation to estimate the synchrotron frequency shift from potential-well distortion. In the second method, the impedance is estimated from the loss of Landau damping threshold, which is also found to be in good agreement with analytical estimations. Beam-based impedance measurements agree well with estimations using the LHC impedance model. Macropartic...

A longitudinal study of age-related changes in intraocular pressure: the Kangbuk Samsung Health Study.

Science.gov (United States)

Zhao, Di; Kim, Myung Hun; Pastor-Barriuso, Roberto; Chang, Yoosoo; Ryu, Seungho; Zhang, Yiyi; Rampal, Sanjay; Shin, Hocheol; Kim, Joon Mo; Friedman, David S; Guallar, Eliseo; Cho, Juhee

2014-09-02

To examine the longitudinal association between age and intraocular pressure (IOP) in a large sample of Korean men and women. We conducted a prospective cohort study of 274,064 young and middle-aged Korean adults with normal fundoscopic findings, following them from January 1, 2002, to February 28, 2010. Health exams were scheduled annually or biennially. At each visit, IOP was measured in both eyes using automated noncontact tonometers. The longitudinal change in IOP with age was evaluated using three-level mixed models for longitudinal paired-eye data, accounting for correlations between paired eyes and repeated measurements over time. In fully adjusted models, the average longitudinal change in IOP per 1-year increase in age was -0.065 mm Hg (95% confidence interval [CI] -0.068 to -0.063), with marked sex differences (P < 0.001). In men, the average annual IOP change was -0.093 mm Hg (95% CI -0.096 to -0.091) throughout follow-up. In women, the average annual IOP change was -0.006 mm Hg (95% CI -0.010 to -0.003), with a relatively flat association in the age range of 30 to 59 years and more marked annual decreases at younger and older ages. Intraocular pressure was inversely associated with age in a large cohort of Korean adults attending health-screening visits. For men, this inverse association was observed throughout the entire age range, while for women it was evident only in younger (<30 years of age) and older (≥60 years of age) women, with no association in women aged 30 to 59. Further research is needed to better understand the underlying mechanisms and to reconsider cutoffs for defining high IOP by age and sex groups in Asian populations. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

The Job Demands-Job Control Model and absence behaviour : results of a 3-year longitudinal study

NARCIS (Netherlands)

Smulders, P.G.W.; Nijhuis, F.J.N.

1999-01-01

Empirical results of earlier studies only marginally supported the relevance of Karasek's Job Demands-Job Control Model for absence behaviour. Since longitudinal studies with respect to these relations were largely lacking, a four-wave panel study was carried out using data from 1755 male employees

Trajectories of electrons with large longitudinal momenta in the phase plane during surfatron acceleration by an electromagnetic wave

Energy Technology Data Exchange (ETDEWEB)

Mkrtichyan, G. S., E-mail: hay-13@mail.ru [Peoples’ Friendship University of Russia (Russian Federation)

2015-07-15

The trajectories of electrons with large longitudinal momenta in the phase plane in the course of their surfatron acceleration by an electromagnetic wave propagating in space plasma across the external magnetic field are analyzed. Electrons with large longitudinal momenta are trapped immediately if the initial wave phase Ψ(0) on the particle trajectory is positive. For negative values of Ψ(0), no electrons trapping by the wave is observed over the available computational times. According to numerical calculations, the trajectories of trapped particles in the phase plane have a singular point of the stable focus type and the behavior of the trajectory corresponds to the motion in a complex nonstationary effective potential well. For some initial phases, electrons are confined in the region of the accelerating electric field for relatively short time, the energy gain being about 50–130% and more.

Study of CSR longitudinal bunch compression cavity

International Nuclear Information System (INIS)

Yin Dayu; Li Peng; Liu Yong; Xie Qingchun

2009-01-01

The scheme of longitudinal bunch compression cavity for the Cooling Storage Ring (CSR)is an important issue. Plasma physics experiments require high density heavy ion beam and short pulsed bunch,which can be produced by non-adiabatic compression of bunch implemented by a fast compression with 90 degree rotation in the longitudinal phase space. The phase space rotation in fast compression is initiated by a fast jump of the RF-voltage amplitude. For this purpose, the CSR longitudinal bunch compression cavity, loaded with FINEMET-FT-1M is studied and simulated with MAFIA code. In this paper, the CSR longitudinal bunch compression cavity is simulated and the initial bunch length of 238 U 72+ with 250 MeV/u will be compressed from 200 ns to 50 ns.The construction and RF properties of the CSR longitudinal bunch compression cavity are simulated and calculated also with MAFIA code. The operation frequency of the cavity is 1.15 MHz with peak voltage of 80 kV, and the cavity can be used to compress heavy ions in the CSR. (authors)

Person-Organization (Culture) Fit and Employee Commitment under Conditions of Organizational Change: A Longitudinal Study

Science.gov (United States)

Meyer, John P.; Hecht, Tracy D.; Gill, Harjinder; Toplonytsky, Laryssa

2010-01-01

This longitudinal study examines how person-organization fit, operationalized as congruence between perceived and preferred organizational culture, relates to employees' affective commitment and intention to stay with an organization during the early stages of a strategic organizational change. Employees in a large energy company completed surveys…

Measuring adolescents’ exposure to victimization: The Environmental Risk (E-Risk) Longitudinal Twin Study

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Fisher, Helen L.; Caspi, Avshalom; Moffitt, Terrie E.; Wertz, Jasmin; Gray, Rebecca; Newbury, Joanne; Ambler, Antony; Zavos, Helena; Danese, Andrea; Mill, Jonathan; Odgers, Candice L.; Pariante, Carmine; Wong, Chloe C.; Arseneault, Louise

2016-01-01

This paper presents mutlilevel findings on adolescents’ victimization exposure from a large longitudinal cohort of twins. Data were obtained from the Environmental Risk (E-Risk) Longitudinal Twin Study, an epidemiological study of 2,232 children (1,116 twin pairs) followed to 18 years of age (with 93% retention). To assess adolescent victimization we combined best practices in survey research on victimization with optimal approaches to measuring life stress and traumatic experiences, and introduce a reliable system for coding severe victimization. One in three children experienced at least one type of severe victimization during adolescence (crime victimization, peer/sibling victimization, internet/mobile phone victimization, sexual victimization, family violence, maltreatment, or neglect), and most types of victimization were more prevalent amongst children from low socioeconomic backgrounds. Exposure to multiple victimization types was common, as was re-victimization; over half of those physically maltreated in childhood were also exposed to severe physical violence in adolescence. Biometric twin analyses revealed that environmental factors had the greatest influence on most types of victimization, while severe physical maltreatment from caregivers during adolescence was predominantly influenced by heritable factors. The findings from this study showcase how distinct levels of victimization measurement can be harmonized in large-scale studies of health and development. PMID:26535933

A Longitudinal Study of Adolescent Adjustment Following Family Transitions

Science.gov (United States)

Ruschena, Eda; Prior, Margot; Sanson, Ann; Smart, Diana

2005-01-01

Background: This study examined the impact of family transitions, that is, parental separation, divorce, remarriage and death, upon the lives of Australian children and adolescents in a longitudinal study of temperament and development. Methods: Using longitudinal and concurrent questionnaire data, outcomes for young people experiencing…

Drug Exposure Opportunities and Use Patterns among College Students: Results of a Longitudinal Prospective Cohort Study

Science.gov (United States)

Arria, Amelia M.; Caldeira, Kimberly M.; O'Grady, Kevin E.; Vincent, Kathryn B.; Fitzelle, Dawn B.; Johnson, Erin P.; Wish, Eric D.

2008-01-01

Underage drinking and drug use among college students are major public health concerns, yet few studies have examined these behaviors and their associated risk factors and consequences prospectively. This paper describes the sampling and recruitment methods of a longitudinal study of 1253 college students at a large, mid-Atlantic university.…

Hours in non-parental child care are related to language development in a longitudinal cohort study

NARCIS (Netherlands)

Luijk, M.P.C.M.; Linting, M.; Henrichs, J.; Herba, C.M.; Verhage, M.L.; Schenk, J.J.; Arends, L.R.; Raat, H.; Jaddoe, V.W.V.; Hofman, A.; Verhulst, F.C.; Tiemeier, H.; Van IJzendoorn, M.H.

2015-01-01

Background: The effects of child care services on several domains of child development have been extensively investigated, but evidence regarding the effects of child care on language development remains inconclusive. Methods: Within a large-scale population-based study, we examined the longitudinal

Statistical Power in Longitudinal Network Studies

NARCIS (Netherlands)

Stadtfeld, Christoph; Snijders, Tom A. B.; Steglich, Christian; van Duijn, Marijtje

2018-01-01

Longitudinal social network studies may easily suffer from a lack of statistical power. This is the case in particular for studies that simultaneously investigate change of network ties and change of nodal attributes. Such selection and influence studies have become increasingly popular due to the

Nonlinear longitudinal dynamics studies at the ALS

International Nuclear Information System (INIS)

Byrd, J.M.; Cheng, W.-H.; De Santis, S.; Li, D.; Stupakov, G.; Zimmermann, F.

1999-01-01

We present a summary of results for a variety of studies of nonlinear longitudinal dynamics in the Advanced Light Source, an electron storage ring. These include observation of decoherence at injection, decay of an injected beam, forced synchrotron oscillations and diffusion from one bunch to the next. All of the measurements were made using a dual-scan streak camera which allowed the real-time observation of the longitudinal distribution of the electron beam

Empathy and Extracurricular Involvement in Emerging Adulthood: Findings from a Longitudinal Study of Undergraduate College Males

Science.gov (United States)

Hudson-Flege, Matthew; Thompson, Martie P.

2017-01-01

In this study, we analyzed the Interpersonal Reactivity Index Perspective Taking subscale scores for male college students in a 2008-2011 longitudinal study at a large public university in the Southeast. Findings suggest that empathy is amenable to change among college males in the period of emerging adulthood. Through repeated measures analyses…

A Longitudinal Examination of Childhood Maltreatment and Adolescent Obesity: Results from the National Longitudinal Study of Adolescent Health (AddHealth) Study

Science.gov (United States)

Shin, Sunny Hyucksun; Miller, Daniel P.

2012-01-01

Objectives: We sought to explore the association between childhood maltreatment (e.g., neglect, physical and sexual abuse) and longitudinal growth trajectories of body mass index (BMI) from adolescence to young adulthood. Methods: We used latent curve modeling to examine data from the National Longitudinal Study of Adolescent Health (N = 8,471),…

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

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Bos, A.; 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

The First Assembly Line of Large-longitudinally-welded Steel Pipe in China Went into Operation

Institute of Scientific and Technical Information of China (English)

Li Bing

2002-01-01

@@ On July 27, the first assembly line to produce JCOE large diameter Longitudinally-submerged-arc-welded steel pipe in China, Which is the key homemade equipment project of "West-East Gas Transmission"project, was put into production. Chen Gen, vice general manager of CNPC; Xie Zhiqiang and Liu Haisheng, assistant chief manager of CNPC; Shi Xingquan, vice president of PetroChina; and the president of Itochu-Marubeni Steel & iron Co., Ltd.of Japan; attended the opening ceremony and cut the ribbon.

Longitudinal heritability of childhood aggression

NARCIS (Netherlands)

Porsch, R.M.P.; Middeldorp, C.M.; Cherny, S.S.; Krapohl, E.; van Beijsterveldt, C.E.M.; Loukola, A.; Korhonen, T.; Pulkkinen, L.; Corley, R.P.; Rhee, S.; Kaprio, J.; Rose, R.; Hewitt, J.K.; Sham, P.; Plomin, R.; Boomsma, D.I.; Bartels, M.

2016-01-01

The genetic and environmental contributions to the variation and longitudinal stability in childhood aggressive behavior were assessed in two large twin cohorts, the Netherlands Twin Register (NTR), and the Twins Early Development Study (TEDS; United Kingdom). In NTR, maternal ratings on aggression

Large variation in measures used to assess outcomes of opioid dependence treatment: A systematic review of longitudinal observational studies.

Science.gov (United States)

Wiessing, Lucas; Ferri, Marica; Darke, Shane; Simon, Roland; Griffiths, Paul

2017-10-02

Treatment outcomes for drug users are critical for informing policy and therapeutic practice. The coherence of outcomes, changes and drug use measures from observational studies on opioid use treatment were reviewed. Systematic review of the literature for longitudinal observational studies, from 1980 through November 2015, in all languages, with data on treated opioid users, using Pubmed, the Cochrane Library and additional strategies (e.g. Pubmed function 'related citations' and checking reference lists of eligible studies). Twenty-seven studies were included (11 countries, 85 publications, recruitment 1962-2009). Baseline n was >65 686 and median follow-up 34.5 months (21 studies) or 51.4 person-months (10 studies). Eight outcome domains were identified: 'drug use' (21/27 studies), 'crime' (13), 'health' (13), 'treatment-related' outcomes (16), 'social functioning' (13), 'harms' (8), 'mortality' (13) and 'economic estimates' (2 studies). All studies using drug use outcomes included a binary (abstinence) category in at least one measure. Studies typically reported outcomes on less than half (on average 3.7 or 46%) of the eight outcome domains, while the average was 5.1 (64%) in seven studies initiated since 2000. Wide variation exists in outcome measures found in longitudinal observational studies of treatment of opioid users. This reduces replicability of studies and suggests a lack of common expectations on treatment success. Future studies should consider using all or most of eight outcome domains identified (excluding economic analyses if unfeasible), non-binary measures and amount/value of drugs used and consensus meetings with joint ownership of scientific, treatment and patient communities. © 2017 Australasian Professional Society on Alcohol and other Drugs.

Longitudinal patterns of gambling activities and associated risk factors in college students

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Goudriaan, Anna E.; Slutske, Wendy S.; Krull, Jennifer L.; Sher, Kenneth J.

2009-01-01

To investigate which clusters of gambling activities exist within a longitudinal study of college health, how membership in gambling clusters change over time and whether particular clusters of gambling are associated with unhealthy risk behaviour. Four-year longitudinal study (2002-2006). Large,

Modeling Change in Large-Scale Longitudinal Studies of Educational Growth: Four Decades of Contributions to the Assessment of Educational Growth. ETC R&D Scientific and Policy Contributions Series. ETS SPC-12-01. Research Report No. RR-12-04

Science.gov (United States)

Rock, Donald A.

2012-01-01

This paper provides a history of ETS's role in developing assessment instruments and psychometric procedures for measuring change in large-scale national assessments funded by the Longitudinal Studies branch of the National Center for Education Statistics. It documents the innovations developed during more than 30 years of working with…

Modeling Change in Large-Scale Longitudinal Studies of Educational Growth: Four Decades of Contributions to the Assessment of Educational Growth. Research Report. ETS RR-12-04. ETS R&D Scientific and Policy Contributions Series. ETS SPC-12-01

Science.gov (United States)

Rock, Donald A.

2012-01-01

This paper provides a history of ETS's role in developing assessment instruments and psychometric procedures for measuring change in large-scale national assessments funded by the Longitudinal Studies branch of the National Center for Education Statistics. It documents the innovations developed during more than 30 years of working with…

A Longitudinal Study of Usability in Health Care

DEFF Research Database (Denmark)

Kjeldskov, Jesper; Skov, Mikael B.; Stage, Jan

2010-01-01

We report from a longitudinal laboratory-based usability evaluation of a health care information system. The purpose of the study was to inquire into the nature of usability problems experienced by novice and expert users, and to see to what extend usability problems of a health care information...... system may or may not disappear over time, as the nurses get more familiar with it-if time heals poor design? As our method for studying this, we conducted a longitudinal study with two key studies. A usability evaluation was conducted with novice users when an electronic patient record system was being......, we discuss implications for evaluating usability in health care....

Residents’ perceptions of an integrated longitudinal curriculum: a qualitative study

Directory of Open Access Journals (Sweden)

Rebecca Lubitz

2015-12-01

Conclusions: This study suggests that an integrated longitudinalized family medicine block training model has the potential to support the principles of a longitudinal integrated competency-based curriculum to effectively prepare residents for family medicine practice.

Longitudinal drop-out and weighting against its bias

Directory of Open Access Journals (Sweden)

Steffen C. E. Schmidt

2017-12-01

Full Text Available Abstract Background The bias caused by drop-out is an important factor in large population-based epidemiological studies. Many studies account for it by weighting their longitudinal data, but to date there is no detailed final approach for how to conduct these weights. Methods In this study we describe the observed longitudinal bias and a three-step longitudinal weighting approach used for the longitudinal data in the MoMo baseline (N = 4528, 4–17 years and wave 1 study with 2807 (62% participants between 2003 and 2012. Results The most meaningful drop-out predictors were socioeconomic status of the household, socioeconomic characteristics of the mother and daily TV usage. Weighting reduced the bias between the longitudinal participants and the baseline sample, and also increased variance by 5% to 35% with a final weighting efficiency of 41.67%. Conclusions We conclude that a weighting procedure is important to reduce longitudinal bias in health-oriented epidemiological studies and suggest identifying the most influencing variables in the first step, then use logistic regression modeling to calculate the inverse of the probability of participation in the second step, and finally trim and standardize the weights in the third step.

Longitudinal coupled-bunch instability studies in the PS

CERN Document Server

Damerau, H

2017-01-01

The main longitudinal limitation for LHC-type beams inthe PS are coupled-bunch instabilities. A dedicated proto-typefeedbacksystemusingaFinemetcavityasalongitudinalkicker has been installed. Extensive tests with beam havebeen performed to explore the intensity reach with this feed-back. The maximum intensity with nominal longitudinalemittance at PS extraction has been measured, as well as theemittance required to keep the beam longitudinally stableat the design intensity for the High-Luminosity LHC (HL-LHC). A higher-harmonic cavity is a complementary op-tion to extend the intensity reach beyond the capabilities ofthe coupled-bunch feedback. Preliminary machine develop-ment (MD) studies operating one20MHzor one40MHzRF system as a higher harmonic at the flat-top indicate thebeneficial effect on longitudinal beam stability

LEIR longitudinal studies

CERN Document Server

Albright, S; Hancock, S

2017-01-01

Towards the end of 2015 and during 2016 there were exten-sive studies of longitudinal beam dynamics in LEIR aimedat improving extracted intensities. As the driving source oflosses early in the ramp was shown to be transverse spacecharge tune spread a significant improvement came fromflattening the beam profile to increase the bunching factorby offsetting the RF frequency from the beam revolution fre-quency. Further benefits were provided by modulating theRF frequency during capture, leading to emittance blow-upand improved reproducibility. The use of two RF cavitiesduring operation was studied to try and further increase thecaptured emittance, however after careful alignment of theRF it was found that a hard limit in the bunch heigh of approx-imately 7 MeV exists. Due to the acceptance limit there wasno operational benefit to using both cavities simultaneously

A longitudinal study of growth, sex steroids and IGF-1 in boys with physiological gynaecomastia

DEFF Research Database (Denmark)

Mieritz, Mikkel G.; Raket, Lars Lau; Hagen, Casper P.

2015-01-01

Context: Physiological gynaecomastia is common and affects a large proportion of otherwise healthy adolescent boys. It is thought to be caused by an imbalance between estrogen and testosterone, though this is rarely evident in analyses of serum. Objective: This study aimed to describe the frequency...... of physiological gynaecomastia, and to determine possible etiological factors (e.g. auxology and serum hormone levels) in a longitudinal set-up. Design, Settings and Participants: A prospective cohort study of 106 healthy Danish boys (5.8–16.4 years) participated in the longitudinal part of “the COPENHAGEN Puberty......, pubertal development and the presence of gynaecomastia were evaluated at each visit. Results: 52 of 106 boys (49 developed gynaecomastia of which 10 (19 presented with intermittent gynaecomastia. Boys with physiological gynaecomastia reached peak height velocity at a significantly younger age than boys who...

A Longitudinal Study of a 5th Grade Science Curriculum Based on the 5E Model

Science.gov (United States)

Scott, Timothy P.; Schroeder, Carolyn; Tolson, Homer; Huang, Tse-Yang; Williams, Omah M.

2014-01-01

The Center for Mathematics and Science Education at Texas A&M University contracted with Region 4 Education Service Center (ESC) and a large, diverse school district to conduct a longitudinal study from 2005-2009. The state achievement test scores of 5th graders who were taught using a Grade 5 science textbook designed by Region 4 ESC were…

Adult Attachment, Social Self-Efficacy, Self-Disclosure, Loneliness, and Subsequent Depression for Freshman College Students: A Longitudinal Study

Science.gov (United States)

Wei, Meifen; Russel, Daniel W.; Zakalik, Robyn A.

2005-01-01

This longitudinal study examined whether social self-efficacy and self-disclosure serve as mediators between attachment and feelings of loneliness and subsequent depression. Participants were 308 freshmen at a large Midwestern university. Results indicated that social self-efficacy mediated the association between attachment anxiety and feelings…

Changes in gait characteristics of women with early and established medial knee osteoarthritis : Results from a 2-years longitudinal study

NARCIS (Netherlands)

Mahmoudian, Armaghan; van Dieёn, Jaap H.; Baert, Isabel A.C.; Bruijn, Sjoerd M.; Faber, Gert S.; Luyten, Frank P.; Verschueren, Sabine M.P.

2017-01-01

Background Despite the large number of cross-sectional studies on gait in subjects with knee osteoarthritis, there are scarcely any longitudinal studies on gait changes in knee osteoarthritis. Methods Gait analysis was performed on 25 women with early and 18 with established medial knee

Are Sibling Relationships Protective? A Longitudinal Study

Science.gov (United States)

Gass, Krista; Jenkins, Jennifer; Dunn, Judy

2007-01-01

Background: Although the protective effects of familial and parental support have been studied extensively in the child psychopathology literature, few studies have explored the protective quality of positive sibling relationships. Methods: A two-wave longitudinal design was used to examine the protective effect of positive sibling relationships…

Longitudinal tracking studies for a high intensity proton synchrotron

International Nuclear Information System (INIS)

Lessner, E.; Cho, Y.; Harkay, K.; Symon, K.

1995-01-01

Results from longitudinal tracking studies for a high intensity proton synchrotron designed for a 1-MW spallation source are presented. The machine delivers a proton beam of 0.5 mA time-averaged current at a repetition rate of 30 Hz. The accelerator is designed to have radiation levels that allow hands-on-maintenance. However, the high beam intensity causes strong space charge fields whose effects may lead to particle loss and longitudinal instabilities. The space charge fields modify the particle distribution, distort the stable bucket area and reduce the rf linear restoring force. Tracking simulations were conducted to analyze the space charge effects on the dynamics of the injection and acceleration processes and means to circumvent them. The tracking studies led to the establishment of the injected beam parameters and rf voltage program that minimized beam loss and longitudinal instabilities. Similar studies for a 10-GeV synchrotron that uses the 2-GeV synchrotron as its injector are also discussed

Collaborative Knowledge-Building: A Longitudinal Study

Science.gov (United States)

Li, Qing

2009-01-01

The focus of this paper is on knowledge-building in a technology-supported learning environment in higher education through a longitudinal study of a graduate course from 2003 to 2007. The primary question is: how do learning conditions designed into a graduate course contribute to collaborative knowledge building? In particular, two major…

Associations Between Statin Use and Physical Function in Older Adults from The Netherlands and Australia: Longitudinal Aging Study Amsterdam and Australian Longitudinal Study on Women's Health.

Science.gov (United States)

van Boheemen, Laurette; Tett, Susan E; Sohl, Evelien; Hugtenburg, Jacqueline G; van Schoor, Natasja M; Peeters, G M E E

2016-06-01

Statin therapy may cause myopathy, but long-term effects on physical function are unclear. We investigated whether statin use is associated with poorer physical function in two population-based cohorts of older adults. Data were from 691 men and women (aged 69-102 years in 2005/2006) in the LASA (Longitudinal Aging Study Amsterdam) and 5912 women (aged 79-84 years in 2005) in the ALSWH (Australian Longitudinal Study on Women's Health). Statin use and dose were sourced from containers (LASA) and administrative databases (ALSWH). Physical function was assessed using performance tests, questionnaires on functional limitations and the SF-12 (LASA) and SF-36 (ALSWH) questionnaires. Cross-sectional (both studies) and 3-year prospective associations (ALSWH) were analysed for different statin dosage using linear and logistic regression. In total, 25 % of participants in LASA and 61 % in ALSWH used statins. In the cross-sectional models in LASA, statin users were less likely to have functional limitations (percentage of subjects with at least 1 limitation 63.9 vs. 64.2; odds ratio [OR] 0.6; 95 % confidence interval [CI] 0.3-0.9) and had better SF-12 physical component scores (mean [adjusted] 47.3 vs. 44.5; beta [B] = 2.8; 95 % CI 1.1-4.5); in ALSWH, statin users had better SF-36 physical component scores (mean [adjusted] 37.4 vs. 36.5; B = 0.9; 95 % CI 0.3-1.5) and physical functioning subscale scores (mean [adjusted] 55.1 vs. 52.6; B = 2.4; 95 % CI 1.1-3.8) than non-users. Similar associations were found for low- and high-dose users and in the prospective models. In contrast, no significant associations were found with performance tests. Two databases from longitudinal population studies in older adults gave comparable results, even though different outcome measures were used. In these two large cohorts, statin use was associated with better self-perceived physical function.

Active recruitment and limited participant-load related to high participation in large population-based biobank studies

NARCIS (Netherlands)

van Zon, Sander K. R.; Scholtens, Salome; Reijneveld, Sijmen A.; Smidt, Nynke; Bultmann, Ute

2016-01-01

Objectives: Insight into baseline participation rates and their determinants is crucial for designing future population-based biobank studies. We therefore conducted a systematic review and meta-analysis of baseline participation rates and their determinants in large longitudinal population-based

Preschool Affects Longer Term Literacy and Numeracy: Results from a General Population Longitudinal Study in Northern Ireland

Science.gov (United States)

Melhuish, Edward; Quinn, Louise; Sylva, Kathy; Sammons, Pam; Siraj-Blatchford, Iram; Taggart, Brenda

2013-01-01

The Effective Pre-school Provision in Northern Ireland (EPPNI) project is a longitudinal study of child development from 3 to 11 years. It is one of the first large-scale UK projects to investigate the effects of different kinds of preschool provision, and to relate experience in preschool to child development. In EPPNI, 683 children were randomly…

Burnout development among dentists : a longitudinal study

NARCIS (Netherlands)

te Brake, H.; Smits, N.; Wicherts, J.M.; Gorter, R.C.; Hoogstraten, J.

2008-01-01

Knowledge on the development of burnout among dentists is important for purposes of prevention and intervention. Using a two-wave longitudinal design, this study examined the chronological sequence of the three dimensions of the Maslach Burnout Inventory: emotional exhaustion; depersonalization; and

Accounting for dropout reason in longitudinal studies with nonignorable dropout.

Science.gov (United States)

Moore, Camille M; MaWhinney, Samantha; Forster, Jeri E; Carlson, Nichole E; Allshouse, Amanda; Wang, Xinshuo; Routy, Jean-Pierre; Conway, Brian; Connick, Elizabeth

2017-08-01

Dropout is a common problem in longitudinal cohort studies and clinical trials, often raising concerns of nonignorable dropout. Selection, frailty, and mixture models have been proposed to account for potentially nonignorable missingness by relating the longitudinal outcome to time of dropout. In addition, many longitudinal studies encounter multiple types of missing data or reasons for dropout, such as loss to follow-up, disease progression, treatment modifications and death. When clinically distinct dropout reasons are present, it may be preferable to control for both dropout reason and time to gain additional clinical insights. This may be especially interesting when the dropout reason and dropout times differ by the primary exposure variable. We extend a semi-parametric varying-coefficient method for nonignorable dropout to accommodate dropout reason. We apply our method to untreated HIV-infected subjects recruited to the Acute Infection and Early Disease Research Program HIV cohort and compare longitudinal CD4 + T cell count in injection drug users to nonusers with two dropout reasons: anti-retroviral treatment initiation and loss to follow-up.

Longitudinal study on osteoarthritis and bone metabolism

Directory of Open Access Journals (Sweden)

L. Postiglione

2011-09-01

Full Text Available Objective: The relationship between Osteoarthritis (OA and Osteoporosis (OP is not well defined due to lacking in longitudinal data, mainly regarding correlations between biochemical factors and OA incidence. Aim of this paper was to investigate the predictive value for OA incidence of bone mass variations and of selected biochemical markers in healthy women participating in a population-based longitudinal study carried out in Naples (Italy. Subjects and Methods: High completion rate (85.2% and statistically adequate sample size were obtained: 139 women (45 to 79 years of age were examined and follow up visit was performed after two years (24±2 months, following the same protocol. Patients underwent medical examination, questionnaire, anthropometric measurements, blood sampling and urine collection. Bone mineral density (BMD measurement was performed by dual energy X-ray absorptiometry (DEXA at the lumbar spine (L1-L4 and femoral neck. Radiographs of dorsal and lumbar spine in lateral view were performed at basal and at 24 months visits; a team of three experts scored radiographs using Kellegren and Lawrence grading. Results: The score was calculated for two individual radiographic features (narrowing of the joint space, presence of osteophytes and as a global score. Results show a relevant percentage, 23% up, of subjects presenting both OA and OP. In the cross-sectional study the presence of osteophytosis correlates with anthropometric variables and PTH levels. In the longitudinal study results show a correlation between serum vitamin D and delta score for osteophytosis (β=0.02 p<0.05. Conclusions: Data obtained outline the importance of further studies on the pathogenetic link between OA and bone metabolism.

Longitudinal transactions between personality and occupational roles : A large and heterogeneous study of job beginners, stayers, and changers

NARCIS (Netherlands)

Denissen, J.J.A.; Ulferts, H.; Lüdtke, O.; Muck, P.M.; Gerstorf, D.

2014-01-01

Social norms are central to theoretical accounts of longitudinal person-environment transactions. On the one hand, individuals are thought to select themselves into social roles that fit their personality. On the other hand, it is assumed that individuals' personality is transformed by the

A longitudinal study of language learners’ images about Russia

Directory of Open Access Journals (Sweden)

Nikitina Larisa

2016-05-01

Full Text Available Several studies in the field of applied linguistics have explored images held by language learners about a target language country. However, for the most part, these studies focused on learners of modern European languages, such as German, Spanish and French and they were conducted in Western educational contexts. Besides, none of the previous investigations attempted to conduct a systematic classification of the language learners’ images. The present longitudinal study addressed these gaps in the research literature. It explored images about Russia held by Malaysian learners of the Russian language in a large university in East Malaysia. This article reports the findings of three questionnaire surveys conducted in 2004, 2007 and 2010. It was found that the images about Russia held by the participants were diverse and clustered around eight countryrelated aspects. Content of some categories of images was stable and changed little over time. Other categories were more fluid and more prone to change. The paper concludes with a discussion of pedagogical implications that can be derived from the findings.

Recurrent respiratory papillomatosis: a longitudinal study comparing severity associated with human papilloma viral types 6 and 11 and other risk factors in a large pediatric population.

Science.gov (United States)

Wiatrak, Brian J; Wiatrak, Deborah W; Broker, Thomas R; Lewis, Linda

2004-11-01

A database was developed for prospective, longitudinal study of recurrent respiratory papillomatosis (RRP) in a large population of pediatric patients. Data recorded for each patient included epidemiological factors, human papilloma virus (HPV) type, clinical course, staged severity of disease at each surgical intervention, and frequency of surgical intervention. The study hypothesizes that patients with HPV type 11 (HPV-11) and patients younger than 3 years of age at diagnosis are at risk for more aggressive and extensive disease. The 10-year prospective epidemiological study used disease staging for each patient with an original scoring system. Severity scores were updated at each surgical procedure. Parents of children with RRP referred to the authors' hospital completed a detailed epidemiological questionnaire at the initial visit or at the first return visit after the study began. At the first endoscopic debridement after study enrollment, tissue was obtained and submitted for HPV typing using polymerase chain reaction techniques and in situ hybridization. Staging of disease severity was performed in real time at each endoscopic procedure using an RRP scoring system developed by one of the authors (B.J.W.). The frequency of endoscopic operative debridement was recorded for each patient. Information in the database was analyzed to identify statistically significant relationships between extent of disease and/or HPV type, patient age at diagnosis, and selected epidemiological factors. The study may represent the first longitudinal prospective analysis of a large pediatric RRP population. Fifty-eight of the 73 patients in the study underwent HPV typing. Patients infected with HPV-11 were significantly more likely to have higher severity scores, require more frequent surgical intervention, and require adjuvant therapy to control disease progression. In addition, patients with HPV-11 RRP were significantly more likely to develop tracheal disease, to require

Study of longitudinal multibunch instabilities for LHC-type beams at the CERN Proton Synchrotron

CERN Document Server

Ventura, Letizia; Migliorati, Mauro; Palumbo, Luigi

This Master thesis work has been carried out at CERN in the framework of the LHC (Large Hadron Collider) Injector upgrade program (LIU). Longitudinal coupled-bunch (CB) oscillations are an important limitation for the high-brightness beam accelerated in the CERN Proton Synchrotron. Up to present intensities they are suppressed by a dedicated feedback system limited to the first two dominant oscillation modes. In view of the proposed installation of a new wide-band FB system in the framework of the LIU program, measurements have been performed on the old system with the aim of dimensioning the new one. A new simulation program, called LCBC ( Longitudinal Coupled Bunch Simulation), has been used to study the behaviour of the CB FB. By means of this code I have started an extensive simulation campaign to benchmark the code with the theory of coupled bunch and to confirm that the 10 MHz cavity system is the main cause of the coupled bunch instabilities in the CERN PS.

Longitudinal variability of time-location/activity patterns of population at different ages: a longitudinal study in California

Directory of Open Access Journals (Sweden)

Cassady Diana L

2011-09-01

Full Text Available Abstract Background Longitudinal time-activity data are important for exposure modeling, since the extent to which short-term time-activity data represent long-term activity patterns is not well understood. This study was designed to evaluate longitudinal variations in human time-activity patterns. Method We report on 24-hour recall diaries and questionnaires collected via the internet from 151 parents of young children (mostly under age 55, and from 55 older adults of ages 55 and older, for both a weekday and a weekend day every three months over an 18-month period. Parents also provided data for their children. The self-administrated diary and questionnaire distinguished ~30 frequently visited microenvironments and ~20 activities which we selected to represent opportunities for exposure to toxic environmental compounds. Due to the non-normal distribution of time-location/activity data, we employed generalized linear mixed-distribution mixed-effect models to examine intra- and inter-individual variations. Here we describe variation in the likelihood of and time spent engaging in an activity or being in a microenvironment by age group, day-type (weekday/weekend, season (warm/cool, sex, employment status, and over the follow-up period. Results As expected, day-type and season influence time spent in many location and activity categories. Longitudinal changes were also observed, e.g., young children slept less with increasing follow-up, transit time increased, and time spent on working and shopping decreased during the study, possibly related to human physiological changes with age and changes in macro-economic factors such as gas prices and the economic recession. Conclusions This study provides valuable new information about time-activity assessed longitudinally in three major age groups and greatly expands our knowledge about intra- and inter-individual variations in time-location/activity patterns. Longitudinal variations beyond weekly and

The Czech longitudinal study of optimal development

Czech Academy of Sciences Publication Activity Database

Kebza, V.; Šolcová, Iva; Kodl, M.; Kernová, V.

2012-01-01

Roč. 47, Suppl. 1 (2012), s. 266-266 ISSN 0020-7594. [International Congress of Psychology /30./. 22.07.2012-27.07.2012, Cape Town] R&D Projects: GA ČR GAP407/10/2410 Institutional support: RVO:68081740 Keywords : optimal development * Prague longitudinal study Subject RIV: AN - Psychology

Comparing Longitudinal Profile Patterns of Mathematics and Reading in Early Child Longitudinal Study, Kindergarten: The Profile Analysis via Multidimensional Scaling (PAMS) Approach

Science.gov (United States)

Kim, Se-Kang

2010-01-01

The aim of the study is to compare longitudinal patterns from Mathematics and Reading data from the direct child assessment of Early Child Longitudinal Study, Kindergarten (ECLS-K, US Department of Education, National Center for Education Statistics 2006), utilizing Profile Analysis via Multidimensional Scaling (PAMS). PAMS has been used initially…

Ecstasy use and depression: a 4-year longitudinal study among an Australian general community sample.

Science.gov (United States)

George, Amanda M; Olesen, Sarah; Tait, Robert J

2013-10-01

Longitudinal, population-based studies can better assess the relationship of ecstasy use with depression. We examined whether change in ecstasy use was associated with change in depressive symptoms/probable depression over a 4-year period, among a large Australian sample. The Personality and Total Health project is a longitudinal general community study of Australians from Canberra and Queanbeyan. Data from the youngest cohort when aged 24-30 (N = 2, 128) and 4 years later (N = 1, 977) was included. The Goldberg depression scale and the Brief Patient Health Questionnaire measured depressive symptoms and probable depression, respectively. Multilevel growth models also considered demographics, psychosocial characteristics, and other drug use. Ecstasy use was not associated with long-term depressive symptoms or greater odds of depression in multivariate analyses. Users had more self-reported depressive symptoms when using ecstasy compared to not using. However, differences between people who had and had not ever used ecstasy largely accounted for this. Other factors were more important in the prediction of depression. It would be premature to conclude that ecstasy use is not related to the development of long-term depressive symptoms, given the relatively low level of ecstasy and other drug use in this community sample. Results showed that other factors need to be considered when investigating ecstasy use and depression.

A longitudinal study of tooth erosion in adolescents.

NARCIS (Netherlands)

El Aidi, H.; Bronkhorst, E.M.; Truin, G.J.

2008-01-01

Incidence studies on tooth erosion among adolescents are scarce. This longitudinal study aimed at estimating the prevalence, incidence, progression, and distribution of erosion in young adolescents over a 1.5-year period. Erosion at baseline was present in 32.2% of the 622 children (mean age, 11.9

I and Us: A Longitudinal Study on the Interplay of Personal and Social Identity in Adolescence.

Science.gov (United States)

Albarello, Flavia; Crocetti, Elisabetta; Rubini, Monica

2018-04-01

The development of personal and social identity is crucial in adolescence. On the one hand, adolescents face the task of forming and consolidating their personal identity in multiple domains, with educational and interpersonal domains particularly salient. On the other hand, they enlarge their social horizon and increasingly define themselves as members of multiple peer groups, such as groups of classmates and friends met outside school. There is however a lack of integrative research on the interplay among and between personal and social identity processes. Hence the purpose of this study was threefold. First, we examined how personal identity processes in the educational and interpersonal domains are associated longitudinally. Second, we investigated to what extent social identifications with classmates and with the group of friends are associated over time. Third, with an original approach we examined the longitudinal interplay between personal and social identity processes, to connect theoretical contributions that have so far proceeded largely in parallel. Participants were 304 adolescents (61.84% female, M age  = 17.49) involved in a three-wave longitudinal study. We found that (a) the ways in which adolescents develop their identity in the educational and interpersonal domains become more closely intertwined over time; (b) identifications with classmates and with the group of friends are interconnected; and (c) personal and social identity processes are associated both concurrently and longitudinally, with most cross-lagged effects showing that social identifications influence personal identity formation and consolidation in the interpersonal identity domain. Theoretical implications are discussed.

The impact of an unfavorable depression course on network size and loneliness in older people: a longitudinal study in the community.

NARCIS (Netherlands)

Theo van Tilburg; Peter van de Ven; Aartjan Beekman; Wim Houtjes; Dorly Deeg; prof Berno van Meijel

2014-01-01

OBJECTIVE: This work aims to gain insight into the long-term impact of depression course on social network size and perceived loneliness in older people living in the community. METHODS: Within a large representative sample of older people in the community (Longitudinal Aging Study Amsterdam

Group heterogeneity increases the risks of large group size: a longitudinal study of productivity in research groups.

Science.gov (United States)

Cummings, Jonathon N; Kiesler, Sara; Bosagh Zadeh, Reza; Balakrishnan, Aruna D

2013-06-01

Heterogeneous groups are valuable, but differences among members can weaken group identification. Weak group identification may be especially problematic in larger groups, which, in contrast with smaller groups, require more attention to motivating members and coordinating their tasks. We hypothesized that as groups increase in size, productivity would decrease with greater heterogeneity. We studied the longitudinal productivity of 549 research groups varying in disciplinary heterogeneity, institutional heterogeneity, and size. We examined their publication and citation productivity before their projects started and 5 to 9 years later. Larger groups were more productive than smaller groups, but their marginal productivity declined as their heterogeneity increased, either because their members belonged to more disciplines or to more institutions. These results provide evidence that group heterogeneity moderates the effects of group size, and they suggest that desirable diversity in groups may be better leveraged in smaller, more cohesive units.

Longitudinal study of prognostic factors in established periodontitis patients.

Science.gov (United States)

Machtei, E E; Dunford, R; Hausmann, E; Grossi, S G; Powell, J; Cummins, D; Zambon, J J; Genco, R J

1997-02-01

Numerous indicators for disease progression have been described in the last decade. The purpose of this study was to examine, longitudinally, a large battery of clinical, microbiological, and immunological indicators, to try to determine whether the presence of one or a combination of these parameters at baseline, would correlate positively with increased attachment and or bone loss (true prognostic factors). Following initial screening, 79 patients with established periodontitis were monitored longitudinally for one year. Whole mouth clinical measurements, plaque gingival and calculus indices, together with pocket depth and attachment level measurements, were repeated every three months. Full mouth radiographic survey, performed at baseline and 12 months, served to determine changes in crestal bone height using an image enhancement technique. Subgingival plaque samples were taken at baseline and every 3 months. Immunofluorescence assays were performed for the a battery of target microorganisms. Serum and GCF samples for IgG subclasses analysis were obtained at each visit and assayed using ELISA techniques. Likewise blood, samples were also drawn at each visit for a quantitative analysis of serum cotinine level. The overall mean attachment loss (AL) and bone loss (BL) were almost identical (0.159 mm and 0.164 mm, respectively). Individual patients variation was large (-0.733 to +1.004 mm). An overall 6.89% of sites were active; individual patients' means ranged from 0-28.9%. Mean pocket depth (PD) showed minimal change over the study period (-0.033 mm) thus suggesting that most if not all the AL was accompained by concomitant gingival recession. Smokers exhibited greater AL and radiographic BL compared to non-smokers. Likewise, patients' cotinine level showed direct correlation with outcomes of progressive periodontal breakdown. Past severity of periodontal involvement, as reflected in the patients baseline PD, AL and crestal bone height, showed good correlation

A Longitudinal Study of School Districts' Sustained Improvement

Science.gov (United States)

Sampson, Pauline M.

2011-01-01

In this longitudinal study of one region in the state of Texas, there was an examination of district leadership and the sustaining of high student achievement for their districts. The results of this study suggest that sustained improvement of student achievement is very difficult. The districts that had sustained improvement had stable district…

Work-self balance : a longitudinal study on the effects of job demands and resources on personal functioning in Japanese working parents

NARCIS (Netherlands)

Demerouti, E.; Shimazu, A.; Bakker, A.B.; Shimada, K.; Kawakami, N.

2013-01-01

In work-family research the effects on the individual, or the "self", in terms of personal interests independent of the work and family domains, have been largely neglected. This longitudinal study on 471 Japanese employees with young children investigated how job demands and job resources may have

Longitudinal Andhra Pradesh Eye Disease Study: rationale, study design and research methodology.

Science.gov (United States)

Khanna, Rohit C; Murthy, Gudlavalleti Vs; Marmamula, Srinivas; Mettla, Asha Latha; Giridhar, Pyda; Banerjee, Seema; Shekhar, Konegari; Chakrabarti, Subhabrata; Gilbert, Clare; Rao, Gullapalli N

2016-03-01

The rationale, objectives, study design and procedures for the longitudinal Andhra Pradesh Eye Disease Study are described. A longitudinal cohort study was carried out. Participants include surviving cohort from the rural component of Andhra Pradesh Eye Disease Study. During 1996-2000, Andhra Pradesh Eye Disease Survey was conducted in three rural (n = 7771) and one urban (n = 2522) areas (now called Andhra Pradesh Eye Disease Study 1). In 2009-2010, a feasibility exercise (Andhra Pradesh Eye Disease Study 2) for a longitudinal study (Andhra Pradesh Eye Disease Study 3) was undertaken in the rural clusters only, as urban clusters no longer existed. In Andhra Pradesh Eye Disease Study 3, a detailed interview will be carried out to collect data on sociodemographic factors, ocular and systemic history, risk factors, visual function, knowledge of eye diseases and barriers to accessing services. All participants will also undergo a comprehensive eye examination including photography of lens, optic disc and retina, Optic Coherence Tomography of the posterior segment, anthropometry, blood pressure and frailty measures. Measures include estimates of the incidence of visual impairment and age-related eye disease (lens opacities, glaucoma and age-related macular degeneration) and the progression of eye disease (lens opacities and myopia) and associated risk factors. Of the 7771 respondents examined in rural areas in Andhra Pradesh Eye Disease Study 1, 5447 (70.1%) participants were traced in Andhra Pradesh Eye Disease Study 2. These participants will be re-examined. Andhra Pradesh Eye Disease Study 3 will provide data on the incidence and progression of visual impairment and major eye diseases and their associated risk factors in India. The study will provide further evidence to aid planning eye care services. © 2015 Royal Australian and New Zealand College of Ophthalmologists.

Single and Serial Fetal Biometry to Detect Preterm and Term Small- and Large-for-Gestational-Age Neonates: A Longitudinal Cohort Study

Science.gov (United States)

Hernandez-Andrade, Edgar; Ahn, Hyunyoung; Garcia, Maynor; Xu, Zhonghui; Korzeniewski, Steven J.; Saker, Homam; Chaiworapongsa, Tinnakorn; Hassan, Sonia S.; Yeo, Lami; Romero, Roberto

2016-01-01

Objectives To assess the value of single and serial fetal biometry for the prediction of small- (SGA) and large-for-gestational-age (LGA) neonates delivered preterm or at term. Methods A cohort study of 3,971 women with singleton pregnancies was conducted from the first trimester until delivery with 3,440 pregnancies (17,334 scans) meeting the following inclusion criteria: 1) delivery of a live neonate after 33 gestational weeks and 2) two or more ultrasound examinations with fetal biometry parameters obtained at ≤36 weeks. Primary outcomes were SGA (95th centile) at birth based on INTERGROWTH-21st gender-specific standards. Fetus-specific estimated fetal weight (EFW) trajectories were calculated by linear mixed-effects models using data up to a fixed gestational age (GA) cutoff (28, 32, or 36 weeks) for fetuses having two or more measurements before the GA cutoff and not already delivered. A screen test positive for single biometry was based on Z-scores of EFW at the last scan before each GA cut-off so that the false positive rate (FPR) was 10%. Similarly, a screen test positive for the longitudinal analysis was based on the projected (extrapolated) EFW at 40 weeks from all available measurements before each cutoff for each fetus. Results Fetal abdominal and head circumference measurements, as well as birth weights in the Detroit population, matched well to the INTERGROWTH-21st standards, yet this was not the case for biparietal diameter (BPD) and femur length (FL) (up to 9% and 10% discrepancy for mean and confidence intervals, respectively), mainly due to differences in the measurement technique. Single biometry based on EFW at the last scan at ≤32 weeks (GA IQR: 27.4–30.9 weeks) had a sensitivity of 50% and 53% (FPR = 10%) to detect preterm and term SGA and LGA neonates, respectively (AUC of 82% both). For the detection of LGA using data up to 32- and 36-week cutoffs, single biometry analysis had higher sensitivity than longitudinal analysis (52% vs 46

Dynamics of a longitudinal current during a magnetic storm

International Nuclear Information System (INIS)

Dolginov, S.Sh.; Zhuzgov, L.N.; Kosacheva, V.P.; Strunnikova, L.N.; Tyurmina, L.O.; Sharova, V.A.; Shkol'nikova, S.I.

1984-01-01

Results, investigating a spatial distribution and the structure of longitudinal currents during a magnetic storm at 18-19.09.81, are presented. It is shown that during the main phase of the storm the large-scale current system expands to the equator, and current density increases. Inside the current layer and to the pole of it there appears intensive small scale longitudinal l currents. During magnetic storm restopation phase the current system segregates into several pairs of opposite directed currents. During further decreasing of geomagnetic activity the large-scale current system is restored+ and its center is shifted to the pole, longitudinal current density being decreased. The invariant width of longitudinal currents is decreased, while the magnitude, Dsub(st), being increased, that is connected to the displacement of an auroral oval to the equator

Unemployment and psychological distress among graduates: A longitudinal study

NARCIS (Netherlands)

Schaufeli, Wilmar B.; Van Yperen, Nico W.

1992-01-01

A longitudinal study which addresses the relationship between unemployment and psychological distress in Dutch technical college graduates is presented. Two samples were studied: sample 1 (N = 635) consisted of students leaving technical college and sample 2 (N = 487) consisted of technical college

The Timing of Maternal Depressive Symptoms and Child Cognitive Development: A Longitudinal Study

Science.gov (United States)

Evans, Jonathan; Melotti, Roberto; Heron, Jon; Ramchandani, Paul; Wiles, Nicola; Murray, Lynne; Stein, Alan

2012-01-01

Background: Maternal depression is known to be associated with impairments in child cognitive development, although the effect of timing of exposure to maternal depression is unclear. Methods: Data collected for the Avon Longitudinal Study of Parents and Children, a longitudinal study beginning in pregnancy, included self-report measures of…

Longitudinal associations between depression and problematic substance use in the Youth Partners in Care study.

Science.gov (United States)

McKowen, James W; Tompson, Martha C; Brown, Timothy A; Asarnow, Joan R

2013-01-01

Large-scale treatment studies suggest that effective depression treatment and reduced depression are associated with improved substance use outcomes. Yet information is limited regarding the longitudinal association between depressive symptoms and problematic substance use and its predictors, particularly in real-world practice settings. Using latent growth modeling, we examined the (a) longitudinal association between depressive symptoms and problematic substance use, (b) impact of depressive symptoms on problematic substance use, (c) impact of problematic substance use on depressive symptoms, and (d) role of co-occurring symptoms on depression and problematic substance use. Participants were part of the Youth Partners in Care study, an effectiveness trial evaluating a quality improvement intervention for youth depression through primary care. This ethnically diverse sample included youths aged 13 to 21 years screening positive for depression from 5 health care organizations. Participants were followed 4 times over an 18-month period and assessed for both depressive symptoms and problematic substance use. Both depressive symptoms and problematic substance use declined over time. Higher baseline depressive symptoms predicted a slower decline in problematic substance use, but baseline problematic substance use did not predict changes in depressive symptoms. These prospective associations remained robust controlling for co-occurring symptoms. Results support prior large-scale depression studies indicating depression burden negatively impacts substance use outcome and extends these findings to real-world practice settings. Findings underscore the importance of addressing depression severity in youth with concurrent substance use problems, even in the context of comorbid symptoms of anxiety, delinquency, and aggression.

Longitudinal follow-up of individual white matter hyperintensities in a large cohort of elderly

Energy Technology Data Exchange (ETDEWEB)

Maillard, Pauline; Crivello, Fabrice; Tzourio-Mazoyer, Nathalie [Universite de Caen, Universite Paris Descartes, Centre d' Imagerie-Neurosciences et Applications aux Pathologies, CI-NAPS, UMR6232, CNRS, CEA, GIP Cyceron, Caen (France); Dufouil, Carole; Tzourio, Christophe [INSERM, Neuroepidemiologie U708, Paris (France); Mazoyer, Bernard [Universite de Caen, Universite Paris Descartes, Centre d' Imagerie-Neurosciences et Applications aux Pathologies, CI-NAPS, UMR6232, CNRS, CEA, GIP Cyceron, Caen (France); Institut Universitaire de France, Paris (France); CHU, GIP Cyceron, Caen (France)

2009-04-15

We report on a method for the longitudinal follow-up of individual white matter hypersignals (WMH) and on its application to the study of WMH natural evolution in a cohort of 1,118 elderly over a 4-year period. For each subject, automated WMH detection was performed on T2-weighted MR images acquired both at baseline and at follow-up after registration in a common space. The detection algorithm was designed both to track WMH previously existing at baseline and to identify newly formed WMH. The average annual change in WMH load was found to be 0.25 cm{sup 3}/year, 36% of this change being attributable to newly formed WMH. Quantitative analyses showed that change in WMH was mainly explained by progression of juxtaventricular and periventricular WMH while the load of WMH in the deep white matter zones was found stable over 4 years of the study. Statistical parametric mapping confirmed these spatial WMH change distributions in the juxta- and periventricular zones. High blood pressure was not a significant predictor of the annual change in WMH. This study proposes a new scheme for the longitudinal study of WMH change by dissociating worsening of existent WMH from surfacing of new WMH and may thus contribute to help understanding and characterizing the neurological and etiological bases of these two processes and their potential differences. (orig.)

Peritoneal Water Transport Characteristics of Diabetic Patients Undergoing Peritoneal Dialysis: A Longitudinal Study.

Science.gov (United States)

Fernandes, Ana; Ribera-Sanchez, Roi; Rodríguez-Carmona, Ana; López-Iglesias, Antía; Leite-Costa, Natacha; Pérez Fontán, Miguel

2017-01-01

Volume overload is frequent in diabetics undergoing peritoneal dialysis (PD), and may play a significant role in the excess mortality observed in these patients. The characteristics of peritoneal water transport in this population have not been studied sufficiently. Following a prospective, single-center design we made cross-sectional and longitudinal comparisons of peritoneal water transport in 2 relatively large samples of diabetic and nondiabetic PD patients. We used 3.86/4.25% glucose-based peritoneal equilibration tests (PET) with complete drainage at 60 min, for these purposes. We scrutinized 59 diabetic and 120 nondiabetic PD patients. Both samples showed relatively similar characteristics, although diabetics were significantly more overhydrated than nondiabetics. The baseline PET disclosed lower ultrafiltration (mean 439 mL diabetics vs. 532 mL nondiabetics, p = 0.033) and sodium removal (41 vs. 53 mM, p = 0.014) rates in diabetics. One hundred and nine patients (36 diabetics) underwent a second PET after 12 months, and 45 (14 diabetics) underwent a third one after 24 months. Longitudinal analyses disclosed an essential stability of water transport in both groups, although nondiabetic patients showed a trend where an increase in free water transport (p = 0.033) was observed, which was not the case in diabetics. Diabetic patients undergoing PD present lower capacities of ultrafiltration and sodium removal than their nondiabetic counterparts. Longitudinal analyses disclose an essential stability of water transport capacities, both in diabetics and nondiabetics. The clinical significance of these differences deserves further analysis. © 2017 S. Karger AG, Basel.

The USA National Longitudinal Lesbian Family Study (NLLFS): homophobia, psychological adjustment, and protective factors

NARCIS (Netherlands)

Bos, H.M.W.; Gartrell, N.K.; Peyser, H.; van Balen, F.

2008-01-01

The study assessed the influence of protective factors on the psychological adjustment of children who had experienced homophobia and whose mothers were participants in a longitudinal study of planned lesbian families. Data were collected as part of the National Longitudinal Lesbian Family Study by

LIA longitudinal coupling impedance

International Nuclear Information System (INIS)

Faltens, A.

1980-01-01

The beam generated fields enter into the problems of waveform generation and longitudinal stability. In the former, provision must be made for the longitudinally defocusing forces due to the space charge and the beam loading effects on the accelerating voltage due to the current of a presumably known bunch. In the latter, the concern is for the growth of unintentional perturbations to unacceptably large values through the interaction of the charge and current fluctuations with the rest of the beam and the surrounding structures. These beam generated electric fields may be related to the beam current through a coupling impedance

Applied longitudinal analysis

CERN Document Server

Fitzmaurice, Garrett M; Ware, James H

2012-01-01

Praise for the First Edition "". . . [this book] should be on the shelf of everyone interested in . . . longitudinal data analysis.""-Journal of the American Statistical Association   Features newly developed topics and applications of the analysis of longitudinal data Applied Longitudinal Analysis, Second Edition presents modern methods for analyzing data from longitudinal studies and now features the latest state-of-the-art techniques. The book emphasizes practical, rather than theoretical, aspects of methods for the analysis of diverse types of lo

A longitudinal study of urea cycle disorders.

Science.gov (United States)

Batshaw, Mark L; Tuchman, Mendel; Summar, Marshall; Seminara, Jennifer

2014-01-01

The Urea Cycle Disorders Consortium (UCDC) is a member of the NIH funded Rare Diseases Clinical Research Network and is performing a longitudinal study of 8 urea cycle disorders (UCDs) with initial enrollment beginning in 2006. The consortium consists of 14 sites in the U.S., Canada and Europe. This report summarizes data mining studies of 614 patients with UCDs enrolled in the UCDC's longitudinal study protocol. The most common disorder is ornithine transcarbamylase deficiency, accounting for more than half of the participants. We calculated the overall prevalence of urea cycle disorders to be 1/35,000, with 2/3rds presenting initial symptoms after the newborn period. We found the mortality rate to be 24% in neonatal onset cases and 11% in late onset cases. The most common precipitant of clinical hyperammonemic episodes in the post-neonatal period was intercurrent infections. Elevations in both blood ammonia and glutamine appeared to be biomarkers for neurocognitive outcome. In terms of chronic treatment, low protein diet appeared to result in normal weight but decreased linear growth while N-scavenger therapy with phenylbutyrate resulted in low levels of branched chain amino acids. Finally, we found an unexpectedly high risk for hepatic dysfunction in patients with ornithine transcarbamylase deficiency. This natural history study illustrates how a collaborative study of a rare genetic disorder can result in an improved understanding of morbidity and disease outcome. Copyright © 2014 Elsevier Inc. All rights reserved.

Tailored Panel Management: A Theory-Based Approach to Building and Maintaining Participant Commitment to a Longitudinal Study.

Science.gov (United States)

Estrada, Mica; Woodcock, Anna; Schultz, P Wesley

2014-02-01

Many psychological processes unfold over time, necessitating longitudinal research designs. Longitudinal research poses a host of methodological challenges, foremost of which is participant attrition. Building on Dillman's work, we provide a review of how social influence and relationship research informs retention strategies in longitudinal studies. Objective: We introduce the tailored panel management (TPM) approach, which is designed to establish communal norms that increase commitment to a longitudinal study, and this commitment, in turn, increases response rates and buffers against attrition. Specifically, we discuss practices regarding compensation, communication, consistency, and credibility that increase longer term commitment to panel participation. Research design: Throughout the article, we describe how TPM is being used in a national longitudinal study of undergraduate minority science students. TheScienceStudy is a continuing panel, which has 12 waves of data collected across 6 academic years, with response rates ranging from 70% to 92%. Although more than 90% of participants have either left or graduated from their undergraduate degree program, this highly mobile group of people remains engaged in the study. TheScienceStudy has usable longitudinal data from 96% of the original panel. Conclusion: This article combines social psychological theory, current best practice, and a detailed case study to illustrate the TPM approach to longitudinal data collection. The approach provides guidance for other longitudinal researchers, and advocates for empirical research into longitudinal research methodologies. © The Author(s) 2014.

Use of missing data methods in longitudinal studies: the persistence of bad practices in developmental psychology.

Science.gov (United States)

Jelicić, Helena; Phelps, Erin; Lerner, Richard M

2009-07-01

Developmental science rests on describing, explaining, and optimizing intraindividual changes and, hence, empirically requires longitudinal research. Problems of missing data arise in most longitudinal studies, thus creating challenges for interpreting the substance and structure of intraindividual change. Using a sample of reports of longitudinal studies obtained from three flagship developmental journals-Child Development, Developmental Psychology, and Journal of Research on Adolescence-we examined the number of longitudinal studies reporting missing data and the missing data techniques used. Of the 100 longitudinal studies sampled, 57 either reported having missing data or had discrepancies in sample sizes reported for different analyses. The majority of these studies (82%) used missing data techniques that are statistically problematic (either listwise deletion or pairwise deletion) and not among the methods recommended by statisticians (i.e., the direct maximum likelihood method and the multiple imputation method). Implications of these results for developmental theory and application, and the need for understanding the consequences of using statistically inappropriate missing data techniques with actual longitudinal data sets, are discussed.

A Longitudinal Study of Gender-Related Cognition and Behaviour

Science.gov (United States)

Campbell, Anne; Shirley, Louisa; Candy, Julia

2004-01-01

Gender schema theory proposes that children's acquisition of gender labels and gender stereotypes informs gender-congruent behaviour. Most previous studies have been cross-sectional and do not address the temporal relationship between knowledge and behaviour. We report the results of a longitudinal study of gender knowledge and sex-typed behaviour…

Continuity of Genetic and Environmental Influences on Cognition across the Life Span: A Meta-Analysis of Longitudinal Twin and Adoption Studies

Science.gov (United States)

Tucker-Drob, Elliot M.; Briley, Daniel A.

2014-01-01

The longitudinal rank-order stability of cognitive ability increases dramatically over the lifespan. Multiple theoretical perspectives have proposed that genetic and/or environmental mechanisms underlie the longitudinal stability of cognition, and developmental trends therein. However, the patterns of stability of genetic and environmental influences on cognition over the lifespan largely remain poorly understood. We searched for longitudinal studies of cognition that reported raw genetically-informative longitudinal correlations or parameter estimates from longitudinal behavior genetic models. We identified 150 combinations of time points and measures from 15 independent longitudinal samples. In total, longitudinal data came from 4,538 monozygotic twin pairs raised together, 7,777 dizygotic twin pairs raised together, 34 monozygotic twin pairs raised apart, 78 dizygotic twin pairs raised apart, 141 adoptive sibling pairs, and 143 non-adoptive sibling pairs, ranging in age from infancy through late adulthood. At all ages, cross-time genetic correlations and shared environmental correlations were substantially larger than cross-time nonshared environmental correlations. Cross-time correlations for genetic and shared environmental components were low during early childhood, increased sharply over child development, and remained relatively high from adolescence through late adulthood. Cross-time correlations for nonshared environmental components were low across childhood and increased gradually to moderate magnitudes in adulthood. Increasing phenotypic stability over child development was almost entirely mediated by genetic factors. Time-based decay of genetic and shared environmental stability was more pronounced earlier in child development. Results are interpreted in reference to theories of gene-environment interaction and correlation. PMID:24611582

Weight restoration therapy rapidly reverses cortical thinning in anorexia nervosa: A longitudinal study.

Science.gov (United States)

Bernardoni, Fabio; King, Joseph A; Geisler, Daniel; Stein, Elisa; Jaite, Charlotte; Nätsch, Dagmar; Tam, Friederike I; Boehm, Ilka; Seidel, Maria; Roessner, Veit; Ehrlich, Stefan

2016-04-15

Structural magnetic resonance imaging studies have documented reduced gray matter in acutely ill patients with anorexia nervosa to be at least partially reversible following weight restoration. However, few longitudinal studies exist and the underlying mechanisms of these structural changes are elusive. In particular, the relative speed and completeness of brain structure normalization during realimentation remain unknown. Here we report from a structural neuroimaging study including a sample of adolescent/young adult female patients with acute anorexia nervosa (n=47), long-term recovered patients (n=34), and healthy controls (n=75). The majority of acutely ill patients were scanned longitudinally (n=35): at the beginning of standardized weight restoration therapy and again after partial weight normalization (>10% body mass index increase). High-resolution structural images were processed and analyzed with the longitudinal stream of FreeSurfer software to test for changes in cortical thickness and volumes of select subcortical regions of interest. We found globally reduced cortical thickness in acutely ill patients to increase rapidly (0.06 mm/month) during brief weight restoration therapy (≈3 months). This significant increase was predicted by weight restoration alone and could not be ascribed to potentially mediating factors such as duration of illness, hydration status, or symptom improvements. By comparing cortical thickness in partially weight-restored patients with that measured in healthy controls, we confirmed that cortical thickness had normalized already at follow-up. This pattern of thinning in illness and rapid normalization during weight rehabilitation was largely mirrored in subcortical volumes. Together, our findings indicate that structural brain insults inflicted by starvation in anorexia nervosa may be reversed at a rate much faster than previously thought if interventions are successful before the disorder becomes chronic. This provides

Longitudinal MRI Study of Cortical Development through Early Childhood in Autism

Science.gov (United States)

Schumann, C.M.; Bloss, C.S.; Barnes, C. Carter; Wideman, G.M.; Carper, R.A.; Akshoomoff, N.; Pierce, K.; Hagler, D.; Schork, N.; Lord, C.; Courchesne, E.

2010-01-01

Cross-sectional MRI studies have long hypothesized that the brain in children with autism undergoes an abnormal growth trajectory that includes a period of early overgrowth; however this has never been confirmed by a longitudinal study. We carried out the first longitudinal study of brain growth in toddlers at the time symptoms of autism are becoming clinically apparent utilizing structural MRI scans at multiple time points beginning at 1.5 years up to 5 years of age. We collected 193 scans on 41 toddlers who received a confirmed diagnosis of Autistic Disorder at ~48 months of age and 44 typically developing controls. By 2.5 years of age, both cerebral gray and white matter was significantly enlarged in toddlers with Autistic Disorder, with the most severe enlargement occurring in frontal, temporal and cingulate cortices. In the longitudinal analyses, which we accounted for age and gender effect, we found that all regions (cerebral gray, cerebral white, frontal gray, temporal gray, cingulate gray, and parietal gray) except occipital gray developed at an abnormal growth rate in toddlers with Autistic Disorder that was mainly characterized by a quadratic age effect. Females with Autistic Disorder displayed a more pronounced abnormal growth profile in more brain regions than males with the disorder. Given that overgrowth clearly begins before 2 years of age, future longitudinal studies would benefit from inclusion of even younger populations as well as further characterization of genetic and other biomarkers in order to determine the underlying neuropathological processes causing the onset of autistic symptoms. PMID:20335478

Parental mediation and cyberbullying - a longitudinal study.

Science.gov (United States)

Chng, Grace S; Liau, Albert; Khoo, Angeline; Li, Dongdong

2014-01-01

Parents use active and restrictive mediation strategies to guide and regulate children's online participation and the online risks they encounter. However, changes in parental mediation do occur over time and the effectiveness of these strategies on cyberbullying demands for further empirical investigation. The current study addresses these issues with a sample of 1084 students (49% girls) in a longitudinal, three-wave design. Gender differences were tested via multi-group analyses. Longitudinal growth models showed that parental use of both active and restrictive mediation decreased over time. For both types of mediation, the mean rate of change had a significant effect on boys' engagement in cyberbullying, but not for girls. Initial levels of restrictive mediation, but not active mediation, were found to be significantly predictive of cyberbullying in both genders. Girls had higher initial levels of both parental mediation types in comparison to boys. The results reveal that the effectiveness of active and restrictive mediation in relation to students' cyberbullying differs and informs us on gender differences. The implications of these results for parental education in online mediation are discussed.

Residents' perceptions of an integrated longitudinal curriculum: a qualitative study.

Science.gov (United States)

Lubitz, Rebecca; Lee, Joseph; Hillier, Loretta M

2015-01-01

The purpose of this study was to explore family medicine residents' perceptions of a newly restructured integrated longitudinal curriculum. A purposeful sample of 16 family medicine residents participated in focus group interviews conducted from a grounded theory perspective to identify the characteristics of this training model that contribute to and that challenge learning. Eight key themes were identified: continuity of care, relevance to family medicine, autonomy, program-focused preparation, professional development as facilitated by role modeling, patient volume, clarity of expectations for learners, and logistics. Positive learning experiences were marked by high levels of autonomy, continuity, and relevance to family medicine. Less favorable learning experiences were characterized by limited opportunities for continuity of care, limited relevance to family medicine practice and unclear expectations for the resident's role. Family physician-led learning experiences contributed to residents' understanding of the full scope of family medicine practice, more so than specialist-led experiences. The logistics of implementing the integrated block were challenging and negatively impacted continuity and learning. This study suggests that an integrated longitudinalized family medicine block training model has the potential to support the principles of a longitudinal integrated competency-based curriculum to effectively prepare residents for family medicine practice.

Longitudinal Emergency Medical Technician Attributes and Demographic Study (LEADS) Design and Methodology.

Science.gov (United States)

Levine, Roger

2016-12-01

The objective of this study is to describe the Longitudinal Emergency Medical Technician (EMT) Attributes and Demographic Study (LEADS) design, instrument development, pilot testing, sampling procedures, and data collection methodology. Response rates are provided, along with results of follow-up surveys of non-responders (NRs) and a special survey of Emergency Medical Services (EMS) professionals who were not nationally certified. Annual surveys from 1999 to 2008 were mailed out to a random, stratified sample of nationally registered EMT-Basics and Paramedics. Survey weights were developed to reflect each respondent's probability of selection. A special survey of NRs was mailed out to individuals who did not respond to the annual survey to estimate the probable extent and direction of response bias. Individuals who indicated they were no longer in the profession were mailed a special exit survey to determine their reasons for leaving EMS. Given the large number of comparisons between NR and regular (annual) survey respondents, it is not surprising that some statistically significant differences were found. In general, there were few differences. However, NRs tended to report higher annual EMS incomes, were younger, healthier, more physically fit, and were more likely to report that they were not practicing EMS. Comparisons of the nationally certified EMS professionals with EMS professionals who were not nationally certified indicated that nationally certified EMS providers were younger, had less EMS experiences, earned less, were more likely to be female and work for private EMS services, and less likely to work for fire-based services. These differences may reflect state and local policy and practice, since many states and local agencies do not require maintenance of national certification as a requirement to practice. When these differences were controlled for statistically, there were few systematic differences between non-nationally certified and nationally

Sex-related and tissue-specific effects of tobacco smoking on brain atrophy: assessment in a large longitudinal cohort of healthy elderly

Directory of Open Access Journals (Sweden)

Quentin eDuriez

2014-11-01

Full Text Available We investigated the cross-sectional and longitudinal effects of tobacco smoking on brain atrophy in a large cohort of healthy elderly participants (65 to 80 years. MRI was used for measuring whole brain (WB, gray matter (GM, white matter (WM, and hippocampus (HIP volumes at study entry time (baseline, N=1,451, and the annualized rates of variation of these volumes using a 4-year follow-up MRI in a subpart of the cohort (N=1,111. Effects of smoking status (never, former, or current smoker at study entry and of lifetime tobacco consumption on these brain phenotypes were studied using sex-stratified AN(COVAs, including other health parameters as covariates. At baseline, male current smokers had lower GM, while female current smokers had lower WM. In addition, female former smokers exhibited reduced baseline HIP, the reduction being correlated with lifetime tobacco consumption. Longitudinal analyses demonstrated that current smokers, whether men or women, had larger annualized rates of HIP atrophy, as compared to either current or former smokers, independent of their lifetime consumption of tobacco. There was no effect of smoking on the annualized rate of WM loss. In all cases, measured sizes of these tobacco-smoking effects were of the same order of magnitude than those of age, and larger than effect sizes of any other covariate. These results demonstrate gender- and tissue specific effects of tobacco smoking on brain atrophy. They indicate that tobacco smoking is a major factor of brain aging, with notable effects on the hippocampus annualized-rate of atrophy after the age of 65.

Longitudinal Effects of Violent Media Usage on Aggressive Behavior—The Significance of Empathy

Directory of Open Access Journals (Sweden)

Thomas Mößle

2014-02-01

Full Text Available The aim of this study was to thoroughly investigate the link between violent media consumption and aggressive behavior. Using a large longitudinal student sample, the role of empathy as a possible mediator of this relationship was of special interest. Data were drawn from wave three to five of the Berlin Longitudinal Study Media, a four-year longitudinal control group study with 1207 school children. Participants completed measures of media usage (violent content of TV and computer games, aggressive behavior perpetration, and empathy. The average age of participants was 10.4 years at Time 1 and 12.4 years at Time 3. Half of the study sample was male (50%. Trivariate structural equation modeling using three measurement times were conducted for assessing the role of empathy as a mediator of the longitudinal relationship between the usage of violent media content and aggressive behavior. For male students empathic skills were shown to unfold a key mediating role between problematic media usage and aggressive behavior.

Changes in HRM in Europe: A Longitudinal Comparative Study among 18 European Countries

Science.gov (United States)

Nikandrou, Irene; Apospori, Eleni; Papalexandris, Nancy

2005-01-01

Purpose: To examine HRM strategies and practices and HRM position within organizations in various cultural, economic and sociopolitical contexts from a longitudinal perspective. Design/methodology/approach: The study uses the 1995 and 1999 Cranet data in a longitudinal methodological framework to explore the changes and trends in 18 European…

A prospective longitudinal study to estimate the prevalence of ...

African Journals Online (AJOL)

A prospective longitudinal study to estimate the prevalence of obesity in Egyptian children with nocturnal enuresis and the association between body mass index and ... Egyptian Journal of Medical Human Genetics ... Response to the treatment was evaluated statistically and correlated with body mass index percentile.

A Longitudinal Study on Learner Career Advancement in MOOCs

Science.gov (United States)

Wang, Yuan; Paquette, Luc; Baker, Ryan

2014-01-01

In this paper, we present progress towards a longitudinal study of the post-course career advancement of MOOC learners. We present initial results and analysis plans for how to link this to in-course behaviour, towards better understanding the goals of all MOOC learners.

A Longitudinal Study of Usability in Health Care - Does Time Heal?

DEFF Research Database (Denmark)

Kjeldskov, Jesper; Skov, Mikael B.; Stage, Jan

2007-01-01

for 15 months, we repeated the evaluation. Our aim was to inquire into the nature of usability problems experienced by novice and expert users, and to see to what extend usability problems of a health care information system may or may not disappear over time, as the nurses get more familiar......We report from a longitudinal laboratory-based usability evaluation of a health care information system. A usability evaluation was conducted with novice users when an electronic patient record system was being deployed in a large hospital. After the nurses had used the system in their daily work...... with it – if time heals poor design. On the basis of our study, we present findings on the usability of the electronic patient system as experienced by the nurses at these two different points in time and discuss implications for evaluating usability in health care....

Multilingualism and fMRI: Longitudinal Study of Second Language Acquisition

Science.gov (United States)

Andrews, Edna; Frigau, Luca; Voyvodic-Casabo, Clara; Voyvodic, James; Wright, John

2013-01-01

BOLD fMRI is often used for the study of human language. However, there are still very few attempts to conduct longitudinal fMRI studies in the study of language acquisition by measuring auditory comprehension and reading. The following paper is the first in a series concerning a unique longitudinal study devoted to the analysis of bi- and multilingual subjects who are: (1) already proficient in at least two languages; or (2) are acquiring Russian as a second/third language. The focus of the current analysis is to present data from the auditory sections of a set of three scans acquired from April, 2011 through April, 2012 on a five-person subject pool who are learning Russian during the study. All subjects were scanned using the same protocol for auditory comprehension on the same General Electric LX 3T Signa scanner in Duke University Hospital. Using a multivariate analysis of covariance (MANCOVA) for statistical analysis, proficiency measurements are shown to correlate significantly with scan results in the Russian conditions over time. The importance of both the left and right hemispheres in language processing is discussed. Special attention is devoted to the importance of contextualizing imaging data with corresponding behavioral and empirical testing data using a multivariate analysis of variance. This is the only study to date that includes: (1) longitudinal fMRI data with subject-based proficiency and behavioral data acquired in the same time frame; and (2) statistical modeling that demonstrates the importance of covariate language proficiency data for understanding imaging results of language acquisition. PMID:24961428

Multilingualism and fMRI: Longitudinal Study of Second Language Acquisition

Directory of Open Access Journals (Sweden)

John Wright

2013-05-01

Full Text Available BOLD fMRI is often used for the study of human language. However, there are still very few attempts to conduct longitudinal fMRI studies in the study of language acquisition by measuring auditory comprehension and reading. The following paper is the first in a series concerning a unique longitudinal study devoted to the analysis of bi- and multilingual subjects who are: (1 already proficient in at least two languages; or (2 are acquiring Russian as a second/third language. The focus of the current analysis is to present data from the auditory sections of a set of three scans acquired from April, 2011 through April, 2012 on a five-person subject pool who are learning Russian during the study. All subjects were scanned using the same protocol for auditory comprehension on the same General Electric LX 3T Signa scanner in Duke University Hospital. Using a multivariate analysis of covariance (MANCOVA for statistical analysis, proficiency measurements are shown to correlate significantly with scan results in the Russian conditions over time. The importance of both the left and right hemispheres in language processing is discussed. Special attention is devoted to the importance of contextualizing imaging data with corresponding behavioral and empirical testing data using a multivariate analysis of variance. This is the only study to date that includes: (1 longitudinal fMRI data with subject-based proficiency and behavioral data acquired in the same time frame; and (2 statistical modeling that demonstrates the importance of covariate language proficiency data for understanding imaging results of language acquisition.

Multilingualism and fMRI: Longitudinal Study of Second Language Acquisition.

Science.gov (United States)

Andrews, Edna; Frigau, Luca; Voyvodic-Casabo, Clara; Voyvodic, James; Wright, John

2013-05-28

BOLD fMRI is often used for the study of human language. However, there are still very few attempts to conduct longitudinal fMRI studies in the study of language acquisition by measuring auditory comprehension and reading. The following paper is the first in a series concerning a unique longitudinal study devoted to the analysis of bi- and multilingual subjects who are: (1) already proficient in at least two languages; or (2) are acquiring Russian as a second/third language. The focus of the current analysis is to present data from the auditory sections of a set of three scans acquired from April, 2011 through April, 2012 on a five-person subject pool who are learning Russian during the study. All subjects were scanned using the same protocol for auditory comprehension on the same General Electric LX 3T Signa scanner in Duke University Hospital. Using a multivariate analysis of covariance (MANCOVA) for statistical analysis, proficiency measurements are shown to correlate significantly with scan results in the Russian conditions over time. The importance of both the left and right hemispheres in language processing is discussed. Special attention is devoted to the importance of contextualizing imaging data with corresponding behavioral and empirical testing data using a multivariate analysis of variance. This is the only study to date that includes: (1) longitudinal fMRI data with subject-based proficiency and behavioral data acquired in the same time frame; and (2) statistical modeling that demonstrates the importance of covariate language proficiency data for understanding imaging results of language acquisition.

Stability and change in adult personality over 6 years: findings from the Victoria Longitudinal Study.

Science.gov (United States)

Small, Brent J; Hertzog, Christopher; Hultsch, David F; Dixon, Roger A

2003-05-01

Data from the Victoria Longitudinal Study were used to examine the 6-year longitudinal stability of personality in older adults. Personality was measured with the NEO Personality Inventory. The longitudinal sample consisted of 223 adults initially ranging from 55 to 85 years of age. Longitudinal confirmatory factor analyses were used to examine the stability of individual differences in change over time, and the stability of the longitudinal factor structure. The results indicated both substantial stability at the level of individual differences in change, as well as significant individual differences in change that were related to age and gender. Finally, the factor structure of personality was invariant over time but did not approximate simple structure for the five dimensions of personality. Our study of 6-year personality development provided both (a). a confirmation of early significant stability findings and (b). unique evidence for significant individual differences in late adulthood.

Longitudinal associations of lifestyle factors and weight status with insulin resistance (HOMA-IR) in preadolescent children: the large prospective cohort study IDEFICS.

Science.gov (United States)

Peplies, Jenny; Börnhorst, Claudia; Günther, Kathrin; Fraterman, Arno; Russo, Paola; Veidebaum, Toomas; Tornaritis, Michael; De Henauw, Stefaan; Marild, Staffan; Molnar, Dénes; Moreno, Luis A; Ahrens, Wolfgang

2016-09-02

This study investigates prospective associations of anthropometrical and lifestyle indices with insulin resistance (IR) in European children from the IDEFICS cohort. Insulin resistance (IR) is a growing concern in childhood obesity and a central aspect of the metabolic syndrome (MS). It most likely represents the link between obesity and type 2 diabetes. This longitudinal study included 3348 preadolescent children aged 3 to 10.9 years from 8 European countries who were observed from 2007/2008 to 2009/2010. The main outcome measure in the present analysis is HOMA-IR (homeostasis model assessment as a common proxy indicator to quantify IR) at follow-up and in its longitudinal development. Anthropometrical measures and lifestyle indices, including objectively determined physical activity, were considered, among others factors, as determinants of IR. Prospective associations between IR at follow-up and anthropometrical and lifestyle indices were estimated by logistic regression models. Country-specific prevalence rates of IR in the IDEFICS cohort of European children showed a positive trend with weight category. Prospective multivariate analyses showed the strongest positive associations of IR with BMI z-score (OR = 2.6 for unit change from the mean, 95 % CI 2.1-3.1) and z-score of waist circumference (OR = 2.2 for unit change from the mean, 95 % CI 1.9-2.6), which were analysed in separate models, but also for sex (OR = 2.2 for girls vs. boys, 95 % CI 1.5-3.1 up to OR 2.5, 95 % CI 1.8-3.6 depending on the model), audio-visual media time (OR = 1.2 for an additional hour per day, 95 % CI 1.0-1.4 in both models) and an inverse association of objectively determined physical activity (OR = 0.5 for 3(rd) compared to 1(st) quartile, 95 % CI 0.3-0.9 in both models). A longitudinal reduction of HOMA-IR was accompanied with a parallel decline in BMI. This study is, to our knowledge, the first prospective study on IR in a preadolescent children

Exploring Longitudinal Risk-return Relationships

DEFF Research Database (Denmark)

Andersen, Torben J.; Bettis, Richard A.

2015-01-01

We study a longitudinal fit model of adaptation and its association with the longitudinal risk-return relationship. The model allows the firm to adjust its position in response to partial learning about a changing environment characterized by two path-dependent processes—a random walk and a stoch......We study a longitudinal fit model of adaptation and its association with the longitudinal risk-return relationship. The model allows the firm to adjust its position in response to partial learning about a changing environment characterized by two path-dependent processes—a random walk...... can lead to the inverse longitudinal risk-return relationships observed empirically. We discuss this apparent paradox and the possible resolution between mindless and conscious behavior as plausible causes of the longitudinal Bowman Paradox....

Modifiable predictors of insufficient sleep durations: A longitudinal analysis of youth in the COMPASS study.

Science.gov (United States)

Patte, Karen A; Qian, Wei; Leatherdale, Scott T

2018-01-01

The purpose of the current study was to simultaneously examine commonly proposed risk and protective factors for sleep deprivation over time among a large cohort of Ontario and Alberta secondary school students. Using 4-year linked longitudinal data from youth in years 1 through 4 (Y 1 [2012/2013], Y 2 [2013/2014], Y 3 [2014/2015], Y 4 [2015/2016]) of the COMPASS study (n=26,205), the likelihood of students meeting contemporary sleep recommendations was tested based on their self-reported substance use, bullying victimization, physical activity, and homework and screen time. Models controlled for the effect of student-reported gender, race/ethnicity, grade, school clustering, and all other predictor variables. Relative to baseline, students became less likely to meet the sleep recommendations if at follow-up they had initiated binge drinking, experienced cyber bullying victimization, or were spending more time doing homework, with other factors held constant. The likelihood of reporting sufficient sleep increased if students had begun engaging in resistance training at least three times a week. No longitudinal effect was observed when students increased their caffeine consumption (energy drinks, coffee/tea), initiated cannabis or tobacco use, experienced other forms of bullying victimization (physical, verbal, or belongings), engaged in more moderate-vigorous physical activity, or increased their screen use of any type. Few of the commonly purported modifiable risk and protective factors for youth sleep deprivation held in multinomial longitudinal analyses. Causal conclusions appear premature, with further research required to confirm the targets likely to be most effective in assisting more youth in meeting the sleep recommendations. Copyright © 2017 Elsevier Inc. All rights reserved.

Second- to Third-Trimester Longitudinal Growth Assessment for the Prediction of Largeness for Gestational Age and Macrosomia in an Unselected Population.

Science.gov (United States)

Caradeux, Javier; Eixarch, Elisenda; Mazarico, Edurne; Basuki, Tri Rahmat; Gratacós, Eduard; Figueras, Francesc

2018-01-01

Prenatal detection of excessive growth remains inaccurate. Most strategies rely on a single cross-sectional evaluation of fetal size during the third trimester. To compare second- to third-trimester longitudinal growth assessment with cross-sectional evaluation at the third trimester in the prediction of largeness for gestational age (LGA) and macrosomia. A cohort of 2,696 unselected singleton pregnancies scanned at 21 ± 2 and 32 ± 2 weeks was created. Abdominal circumference (AC) measurements were transformed to z values according to the INTERGROWTH-21st standards. Longitudinal growth assessment was performed by calculation of z velocity and conditional growth. Both methods were compared to cross-sectional assessment at 32 ± 2 weeks. Predictive performance for LGA and macrosomia was determined by receiver operating characteristic curve analysis. A total of 188 (7%) newborns qualified for LGA and 182 (6.8%) for macrosomia. The areas under the curve (AUCs) for 32-week AC z score, AC z velocity, and conditional AC were 0.78, 0.61, and 0.55, respectively, for the prediction of LGA, and 0.75, 0.61, and 0.55, respectively, for the prediction of macrosomia. Both AUCs of AC z velocity and conditional AC were significantly lower (p third-trimester longitudinal assessment of fetal growth is inferior to third-trimester cross-sectional evaluation of size in the prediction of LGA and macrosomia. © 2017 S. Karger AG, Basel.

Always connected: a longitudinal field study of mobile communication

NARCIS (Netherlands)

Peters, O.; Ben Allouch, Soumaya

2005-01-01

Twenty-five novice users of a new mobile communication device were closely tracked for a period of three months. The results of this longitudinal field study show that people’s motivations for using mobile communication technology are initially influenced more strongly by their perceptions about the

Self-esteem development across the life span: a longitudinal study with a large sample from Germany.

Science.gov (United States)

Orth, Ulrich; Maes, Jürgen; Schmitt, Manfred

2015-02-01

The authors examined the development of self-esteem across the life span. Data came from a German longitudinal study with 3 assessments across 4 years of a sample of 2,509 individuals ages 14 to 89 years. The self-esteem measure used showed strong measurement invariance across assessments and birth cohorts. Latent growth curve analyses indicated that self-esteem follows a quadratic trajectory across the life span, increasing during adolescence, young adulthood, and middle adulthood, reaching a peak at age 60 years, and then declining in old age. No cohort effects on average levels of self-esteem or on the shape of the trajectory were found. Moreover, the trajectory did not differ across gender, level of education, or for individuals who had lived continuously in West versus East Germany (i.e., the 2 parts of Germany that had been separate states from 1949 to 1990). However, the results suggested that employment status, household income, and satisfaction in the domains of work, relationships, and health contribute to a more positive life span trajectory of self-esteem. The findings have significant implications, because they call attention to developmental stages in which individuals may be vulnerable because of low self-esteem (such as adolescence and old age) and to factors that predict successful versus problematic developmental trajectories. PsycINFO Database Record (c) 2015 APA, all rights reserved.

Longitudinal study of the fundamental frequency of hunger cries along the first 6 months of healthy babies.

Science.gov (United States)

Baeck, Heidi Elisabeth; de Souza, Marcio Nogueira

2007-09-01

Potentially rich in information, the baby's cry has motivated several researches along the years. Although most of these studies have generated important knowledge about the baby's cry, they were focused on the neonatal period. The few longitudinal studies on changes in the acoustical features of the cry over the baby's growth have been done with a small sample and a large recording interval. Aiming to overcome such methodological limitations, this work investigated hunger cries using a more representative sample size (30 babies) and time resolution (biweekly intervals) from birth to 6 months of baby's age. The findings indicate that the fundamental frequency (f0) of the cry signals did vary more than previously reported in the literature. The results showed a widespread oscillatory behavior in f0 evolution along all the 6 months with an especially significant decrease from birth to the 15th day of life. The present results are not clinically applicable yet, but they pointed some novel aspects of the f0 mean values along the baby's growth. These findings and further longitudinal studies can help standardize age-related cry parameters, which are essential for medical and language development researches.

The re-identification risk of Canadians from longitudinal demographics

Science.gov (United States)

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

Stress Process of Illicit Drug Use among U.S. Immigrants' Adolescent Children: A Longitudinal Study

Science.gov (United States)

Choo, Hyekyung

2012-01-01

This study examined a full path model of stress process for predicting illicit drug use among Asian and Latino immigrants' adolescent children. Using 2-year longitudinal data (National Longitudinal Study of Adolescent Health) from a sample of adolescents with Asian or Latino immigrant parents (N = 2,353), the study explored structural…

Analysis of Longitudinal Waves in Rod-Type Piezoelectric Phononic Crystals

Directory of Open Access Journals (Sweden)

Longfei Li

2016-04-01

Full Text Available Phononic crystals can be used to control elastic waves due to their frequency bands. This paper analyzes the passive and active control as well as the dispersion properties of longitudinal waves in rod-type piezoelectric phononic crystals over large frequency ranges. Based on the Love rod theory for modeling the longitudinal wave motions in the constituent rods and the method of reverberation-ray matrix (MRRM for deriving the member transfer matrices of the constituent rods, a modified transfer matrix method (MTMM is proposed for the analysis of dispersion curves by combining with the Floquet–Bloch principle and for the calculation of transmission spectra. Numerical examples are provided to validate the proposed MTMM for analyzing the band structures in both low and high frequency ranges. The passive control of longitudinal-wave band structures is studied by discussing the influences of the electrode’s thickness, the Poisson’s effect and the elastic rod inserts in the unit cell. The influences of electrical boundaries (including electric-open, applied electric capacity, electric-short and applied feedback control conditions on the band structures are investigated to illustrate the active control scheme. From the calculated comprehensive frequency spectra over a large frequency range, the dispersion properties of the characteristic longitudinal waves in rod-type piezoelectric phononic crystals are summarized.

Age-related slowing of digit symbol substitution revisited: what do longitudinal age changes reflect?

Science.gov (United States)

MacDonald, Stuart W S; Hultsch, David F; Strauss, Esther; Dixon, Roger A

2003-05-01

A previous investigation reported that cross-sectional age differences in Digit Symbol Substitution (DSS) test performance reflect declines in perceptual processing speed. Support for the tenability of the processing speed hypothesis requires examining whether longitudinal age-related change in DSS performance is largely mediated by changes in speed. The present study used data from the Victoria Longitudinal Study to examine patterns and predictors of longitudinal change in DSS for 512 older adults (M(age) = 68.37 years, SD = 7.43). On the basis of multilevel modeling, baseline DSS performance was poorer for older participants and men, with longitudinal declines more pronounced with increasing age and decreasing speed. In contrast to the present cross-sectional findings, statistical control of change trajectories in perceptual speed using the same data did not substantially attenuate age changes. These discrepancies suggest different sources of variance may underlie cross-sectional age differences and longitudinal age changes for DSS.

The Australian longitudinal study on male health-methods

Directory of Open Access Journals (Sweden)

Dianne Currier

2016-10-01

Full Text Available Abstract Background The Australian Longitudinal Study on Male Health (Ten to Men was established in 2011 to build the evidence base on male health to inform policy and program development. Methods Ten to Men is a national longitudinal study with a stratified multi-stage cluster random sample design and oversampling in rural and regional areas. Household recruitment was conducted from October 2013 to July 2014. Males who were aged 10 to 55 years residing in private dwellings were eligible to participate. Data were collected via self-completion paper questionnaires (participants aged 15 to 55 and by computer-assisted personal interview (boys aged 10 to 14. Household and proxy health data for boys were collected from a parent via a self-completion paper-based questionnaire. Questions covered socio-demographics, health status, mental health and wellbeing, health behaviours, social determinants, and health knowledge and service use. Results A cohort of 15,988 males aged between 10 and 55 years was recruited representing a response fraction of 35 %. Conclusion Ten to Men is a unique resource for investigating male health and wellbeing. Wave 1 data are available for approved research projects.

Longitudinal capture in the radio-frequency-quadrupole structure

International Nuclear Information System (INIS)

Inagaki, S.

1980-03-01

The radio-frequency-quadrupole (RFQ) linac structure not only can attain easily transverse focusing in the low-beta region, but also can obtain very high capture efficiency because of its low beta-lambda and low-particle rigidity. An optimization study of the zero space-charge longitudinal capture in an RFQ linac that yields configurations with large capture efficiency is described

Ultrafast X-ray absorption study of longitudinal-transverse phonon coupling in electrolyte aqueous solution

DEFF Research Database (Denmark)

Jiao, Yishuo; Adams, Bernhard W.; Dohn, Asmus Ougaard

2017-01-01

Ultrafast X-ray absorption spectroscopy is applied to study the conversion of longitudinal to transverse phonons in aqueous solution. Permanganate solutes serve as X-ray probe molecules that permit the measurement of the conversion of 13.5 GHz, longitudinal phonons to 27 GHz, transverse phonons...

Quality of life of elderly individuals receiving literacy training: a longitudinal study

Directory of Open Access Journals (Sweden)

Bruna Rodrigues dos Santos

2015-04-01

Full Text Available Because of population aging in Brazil, educational programs directed to young and adult individuals now have to absorb a large number of 60 year old or older individuals. Objectives: Identify the relationships among the variables quality of life, time attending the program, depressive symptoms, and cognitive status; and longitudinally compare the scores concerning the quality of life of these individuals. Method: Descriptive, correlational, comparative, longitudinal and quantitative study. The participants were elderly individuals who attended literacy training provided in a Brazilian city from 2012 to 2014. The instruments to collect data included sociodemographic characterization, the WHOQOL-bref, WHOQOL-old, the Geriatric Depression Scale (GDS, and the Mini Mental State Examination. Results: The participants were predominantly young-elderly women, with low incomes. Scores obtained on the GDS were related with the domains: Physical (p<0.05; Environment (p<0.01; Autonomy (p<0.01, Past, Present and Future Activities (p<0.05, Intimacy (p<0.01; and Social Relationships (p<0.01. The scores concerning cognition were related to the Autonomy domain (p<0.01. The physical domain of quality of life presented significant worsening in 2013 when compared to 2012 (M1=70.23; M2=61.20;M3=62.40. These results cannot be generalized because they concern only elderly individuals receiving literacy training provided in a midsized city in the interior of São Paulo, Brazil.

Secondary Analysis of National Longitudinal Transition Study 2 Data

Science.gov (United States)

Hicks, Tyler A.; Knollman, Greg A.

2015-01-01

This review examines published secondary analyses of National Longitudinal Transition Study 2 (NLTS2) data, with a primary focus upon statistical objectives, paradigms, inferences, and methods. Its primary purpose was to determine which statistical techniques have been common in secondary analyses of NLTS2 data. The review begins with an…

Is envy harmful to a society's psychological health and wellbeing? A longitudinal study of 18,000 adults.

Science.gov (United States)

Mujcic, Redzo; Oswald, Andrew J

2018-02-01

Nearly 100 years ago, the philosopher and mathematician Bertrand Russell warned of the social dangers of widespread envy. One view of modern society is that it is systematically developing a set of institutions -- such as social media and new forms of advertising -- that make people feel inadequate and envious of others. If so, how might that be influencing the psychological health of our citizens? This paper reports the first large-scale longitudinal research into envy and its possible repercussions. The paper studies 18,000 randomly selected individuals over the years 2005, 2009, and 2013. Using measures of SF-36 mental health and psychological well-being, four main conclusions emerge. First, the young are especially susceptible. Levels of envy fall as people grow older. This longitudinal finding is consistent with a cross-sectional pattern noted recently by Nicole E. Henniger and Christine R. Harris, and with the theory of socioemotional regulation suggested by scholars such as Laura L. Carstensen. Second, using fixed-effects equations and prospective analysis, the analysis reveals that envy today is a powerful predictor of worse SF-36 mental health and well-being in the future. A change from the lowest to the highest level of envy, for example, is associated with a worsening of SF-36 mental health by approximately half a standard deviation (p < .001). Third, no evidence is found for the idea that envy acts as a useful motivator. Greater envy is associated with slower -- not higher -- growth of psychological well-being in the future. Nor is envy a predictor of later economic success. Fourth, the longitudinal decline of envy leaves unaltered a U-shaped age pattern of well-being from age 20 to age 70. These results are consistent with the idea that society should be concerned about institutions that stimulate large-scale envy. Copyright © 2018 Elsevier Ltd. All rights reserved.

Which emotional regulatory strategy makes Chinese adolescents happier? A longitudinal study

NARCIS (Netherlands)

Sang, B.; Deng, X.; Luan, Z.

2014-01-01

Growing interest in emotion regulation is reflected in the studies of cognitive and social development. However, the extant studies mainly highlight how emotion regulation develops based on a western value system. This study utilised a longitudinal design to examine the development of emotion

A longitudinal study of the effects of charismatic leadership and organizational culture on objective and perceived corporate performance

NARCIS (Netherlands)

Wilderom, C.P.M.; van den Berg, P.T.; Wiersma, U.J.

2012-01-01

We investigated the combined effects of charismatic leadership and organizational culture on perceived and objective company performance using a longitudinal design. Employees (N = 1214) in 46 branches of a large Dutch bank rated branch management on charismatic leadership, organizational culture in

A longitudinal study of the effects of charismatic leadership and organizational culture on objective and perceived corporate performance.

NARCIS (Netherlands)

Wilderom, Celeste P.M.; van den Berg, P.T.; Wiersma, U.J.

2012-01-01

We investigated the combined effects of charismatic leadership and organizational culture on perceived and objective company performance using a longitudinal design. Employees (N = 1214) in 46 branches of a large Dutch bank rated branch management on charismatic leadership, organizational culture in

Longitudinal Profiles of Adaptive Behavior in Fragile X Syndrome

Science.gov (United States)

Quintin, Eve-Marie; Jo, Booil; Lightbody, Amy A.; Hazlett, Heather Cody; Piven, Joseph; Hall, Scott S.; Reiss, Allan L.

2014-01-01

OBJECTIVE: To examine longitudinally the adaptive behavior patterns in fragile X syndrome. METHOD: Caregivers of 275 children and adolescents with fragile X syndrome and 225 typically developing children and adolescents (2–18 years) were interviewed with the Vineland Adaptive Behavior Scales every 2 to 4 years as part of a prospective longitudinal study. RESULTS: Standard scores of adaptive behavior in people with fragile X syndrome are marked by a significant decline over time in all domains for males and in communication for females. Socialization skills are a relative strength as compared with the other domains for males with fragile X syndrome. Females with fragile X syndrome did not show a discernible pattern of developmental strengths and weaknesses. CONCLUSIONS: This is the first large-scale longitudinal study to show that the acquisition of adaptive behavior slows as individuals with fragile X syndrome age. It is imperative to ensure that assessments of adaptive behavior skills are part of intervention programs focusing on childhood and adolescence in this condition. PMID:25070318

A Longitudinal Study of Children's Social Behaviors and Their Causal Relationship to Reading Growth

Science.gov (United States)

Lim, Hyo Jin; Kim, Junyeop

2011-01-01

This paper aims at investigating the causal effects of social behaviors on subsequent reading growth in elementary school, using the "Early Childhood Longitudinal Study-Kindergarten" ("ECLS-K") data. The sample was 8,869 subjects who provided longitudinal measures of reading IRT scores from kindergarten (1998-1999) to fifth…

Monitoring of fetuses with intrauterine growth restriction: a longitudinal study

NARCIS (Netherlands)

Hecher, K.; Bilardo, C. M.; Stigter, R. H.; Ville, Y.; Hackelöer, B. J.; Kok, H. J.; Senat, M. V.; Visser, G. H.

2001-01-01

To describe the time sequence of changes in fetal monitoring variables in intrauterine growth restriction and to correlate these findings with fetal outcome at delivery. This was a prospective longitudinal observational multicenter study on 110 singleton pregnancies with growth-restricted fetuses

Experimental study of the longitudinal instability for beam transport

International Nuclear Information System (INIS)

Reiser, M.; Wang, J.G.; Guo, W.M.; Wang, D.X.

1990-01-01

Theoretical model for beam longitudinal instability in a transport pipe with general wall impedance is considered. The result shows that a capacitive wall tends to stabilize the beam. The experimental study of the instability for a pure resistive-wall is presented, including the design parameters, setup and components for the experiment. 6 refs., 3 figs

Procedural justice and prisoners’ mental health problems: A longitudinal study

NARCIS (Netherlands)

Beijersbergen, K.A.; Dirkzwager, A.J.E.; Eichelsheim, V.I.; van der Laan, P.H.; Nieuwbeerta, P.

2013-01-01

Background Given the high prevalence of mental health problems among prisoners, knowledge on its determinants is important. Prior cross-sectional studies suggest that procedurally just treatment within prison is a significant predictor; however, longitudinal research is lacking. Aim The aims of this

Numerical Studies of Electromagnetic Instabilities in Intense Charged Particle Beams with Large Energy Anisotropy

CERN Document Server

Startsev, Edward; Lee, Wei-li

2005-01-01

In intense charged particle beams with large energy anisotropy, free energy is available to drive transverse electromagnetic Weibel-type instabilities. Such slow-wave transverse electromagnetic instabilities can be described by the so-called Darwin model, which neglects the fast-wave portion of the displacement current. The Weibel instability may also lead to an increase in the longitudinal velocity spread, which would make the focusing of the beam difficult and impose a limit on the minimum spot size achievable in heavy ion fusion experiments. This paper reports the results of recent numerical studies of the Weibel instability using the Beam Eigenmode And Spectra (bEASt) code for space-charge-dominated, low-emittance beams with large tune depression. To study the nonlinear stage of the instability, the Darwin model is being developed and incorporated into the Beam Equilibrium Stability and Transport(BEST) code.

A Longitudinal Study Assessing the Microsoft Office Skills Course

Science.gov (United States)

Carpenter, Donald A.; McGinnis, Denise; Slauson, Gayla Jo; Snyder, Johnny

2013-01-01

This paper explains a four-year longitudinal study of the assessment process for a Microsoft Office skills course. It examines whether there is an increase in students' knowledge based on responses to pre- and post-surveys that asked students to evaluate how well they can do particular tasks. Classical classroom teaching methods were used in the…

Mathematics, Language, and Learning: A Longitudinal Study of Elementary Teachers and Their Mathematics Teaching Practices

OpenAIRE

Yeh, Cathery

2016-01-01

Elementary school mathematics has gained increased attention in the last few decades. A growing field of research has studied the programmatic design and development of elementary mathematics teaching in teacher education, however, few studies have examined longitudinally the mathematics teaching of novice elementary teachers. Existing longitudinal studies on elementary mathematics teaching have generally focused on the effects of teacher preparation on their beginning practices and have exam...

Parental Predictors of Children's Shame and Guilt at Age 6 in a Multimethod, Longitudinal Study.

Science.gov (United States)

Parisette-Sparks, Alyssa; Bufferd, Sara J; Klein, Daniel N

2017-01-01

Shame and guilt are self-conscious emotions that begin to develop early in life and are associated with various forms of psychopathology. However, little is known about the factors that contribute to these emotions in young children. Specifically, no longitudinal studies to date have examined a range of parent factors that shape the expression of children's shame and guilt. The current multimethod, longitudinal study sought to determine whether parenting style, parental psychopathology, and parents' marital satisfaction assessed when children were age 3 predict expressions of shame and guilt in children at age 6. A large community sample of families (N = 446; 87.4% Caucasian) with 3-year-old children (45.7% female) was recruited through commercial mailing lists. Parent variables were assessed when children were age 3 with mother- and father-report questionnaires and a diagnostic interview. Children's expressions of shame and guilt were observed in the laboratory at age 6. Fathers', but not mothers', history of depression and permissive parenting assessed when children were age 3 predicted children's expressions of shame and guilt when children were age 6; parents' marital dissatisfaction also predicted children's shame and guilt. These findings suggest that parents, and fathers in particular, contribute to expressions of self-conscious emotions in children. These data on emotional development may be useful for better characterizing the risk and developmental pathways of psychopathology.

Trajectories of Mental Health over 16 Years amongst Young Adult Women: The Australian Longitudinal Study on Women's Health

Science.gov (United States)

Holden, Libby; Ware, Robert S.; Lee, Christina

2016-01-01

This article used data from 5,171 young women participating in the Australian Longitudinal Study on Women's Health, a nationally representative longitudinal cohort study, to identify longitudinal trajectory patterns of mental health across 6 surveys over 16 years of early adulthood, from age 18-23 to age 34-39. In addition, we identified both…

English as a Foreign Language Spelling Development: A Longitudinal Study

Science.gov (United States)

Kahn-Horwitz, Janina; Sparks, Richard L.; Goldstein, Zahava

2012-01-01

English as a foreign language (EFL) spelling was examined longitudinally three times (4th, 9th, 12th grades) during 9 years of EFL study among Hebrew first language (L1) students. The study examined the impact of L1 literacy variables including phonemic awareness, word attack, and spelling on EFL spelling and the relationship between EFL literacy…

Which emotional regulatory strategy makes Chinese adolescents happier? A longitudinal study.

Science.gov (United States)

Sang, Biao; Deng, Xinmei; Luan, Ziyan

2014-12-01

Growing interest in emotion regulation is reflected in the studies of cognitive and social development. However, the extant studies mainly highlight how emotion regulation develops based on a western value system. This study utilised a longitudinal design to examine the development of emotion regulation and explored the contributions of different regulatory strategies to emotion experience regarding the early adolescent development period in a Chinese population. A total of 303 Chinese adolescents (age range = 10-14 years) were followed up in a three-phase longitudinal study for 3 years. In each phase of the study, participants completed Adolescents Emotion Regulation Questionnaire and Daily Emotion Scale. Results of hierarchical linear regressions revealed that Chinese adolescents reported more down-regulation. Down-regulation is more effective than up-regulation in enhancing desirable emotion experience and reducing undesirable emotion experience during adolescents' development. Also, the adaptive functions of emotional regulatory strategies in Chinese background were discussed. © 2014 International Union of Psychological Science.

Accelerated brain aging in schizophrenia : A longitudinal pattern recognition study

NARCIS (Netherlands)

Schnack, Hugo G.; Van Haren, Neeltje E M; Nieuwenhuis, Mireille; Pol, Hilleke E Hulshoff; Cahn, Wiepke; Kahn, René S.

2016-01-01

OBJECTIVE: Despite the multitude of longitudinal neuroimaging studies that have been published, a basic question on the progressive brain loss in schizophrenia remains unaddressed: Does it reflect accelerated aging of the brain, or is it caused by a fundamentally different process? The authors used

Accelerated Brain Aging in Schizophrenia : A Longitudinal Pattern Recognition Study

NARCIS (Netherlands)

Schnack, Hugo G; van Haren, Neeltje E M; Nieuwenhuis, Mireille; Hulshoff Pol, Hilleke E; Cahn, Wiepke; Kahn, René S

2016-01-01

OBJECTIVE: Despite the multitude of longitudinal neuroimaging studies that have been published, a basic question on the progressive brain loss in schizophrenia remains unaddressed: Does it reflect accelerated aging of the brain, or is it caused by a fundamentally different process? The authors used

A Service Member's Self in Transition : A Longitudinal Case Study Analysis

NARCIS (Netherlands)

Grimell, Jan

2017-01-01

Adopting a narrative approach with a dialogical framework, a longitudinal case study is presented that describes a service member's self in transition from active service into the civilian population. An analysis and interpretation of the case study leads to the hypothesis that if a dominant

A Longitudinal Study of Growth, Sex Steroids, and IGF-1 in Boys With Physiological Gynecomastia.

Science.gov (United States)

Mieritz, Mikkel G; Rakêt, Lars L; Hagen, Casper P; Nielsen, John E; Talman, Maj-Lis M; Petersen, Jørgen H; Sommer, Stefan H; Main, Katharina M; Jørgensen, Niels; Juul, Anders

2015-10-01

Physiological gynecomastia is common and affects a large proportion of otherwise healthy adolescent boys. It is thought to be caused by an imbalance between estrogen and testosterone, although this is rarely evident in analyses of serum. This study aimed to describe the frequency of physiological gynecomastia and to determine possible etiological factors (eg, auxology and serum hormone levels) in a longitudinal setup. A prospective cohort study of 106 healthy Danish boys (5.8-16.4 years) participated in the longitudinal part of the COPENHAGEN Puberty Study. The boys were examined every 6 months during an 8-year follow-up. Median number of examinations was 10 (2-15). Blood samples were analyzed for FSH, LH, testosterone, estradiol, SHBG, inhibin B, anti-Müllerian hormone, IGF-1, and IGF binding protein-3 by immunoassays. Auxological parameters, pubertal development, and the presence of gynecomastia were evaluated at each visit. Fifty-two of 106 boys (49%) developed gynecomastia, of which 10 (19%) presented with intermittent gynecomastia. Boys with physiological gynecomastia reached peak height velocity at a significantly younger age than boys who did not develop gynecomastia (13.5 versus 13.9 years, P = .027), and they had significantly higher serum levels of IGF-1 (P = .000), estradiol (P = .013), free testosterone (P Gynecomastia is frequent in pubertal boys. Increased IGF-1 levels and pubertal growth appear to be associated, whereas changes in estrogen to testosterone ratio seem negligible.

A longitudinal study of multidimensional performance characteristics related to physical capacities in youth handball.

Science.gov (United States)

Matthys, Stijn P J; Vaeyens, Roel; Fransen, Job; Deprez, Dieter; Pion, Johan; Vandendriessche, Joric; Vandorpe, Barbara; Lenoir, Matthieu; Philippaerts, Renaat

2013-01-01

Longitudinal research provides valuable information about change and progress towards elite performance. Unfortunately, there is a lack of longitudinal research in handball. In this study, 94 youth handball players (oldest group: n = 41; age 15-17 and youngest group: n = 53; age 13-15) were followed over a three-year period. Repeated measures ANCOVA was conducted to reveal longitudinal changes in anthropometry and physical performance between elite and non-elite players, controlling for maturation. Maturation effects were found for anthropometry (P team handball should recognise the importance of good skills and an excellent endurance for talent identification purposes.

The Effects of the Green House Nursing Home Model on ADL Function Trajectory: A Retrospective Longitudinal Study

Science.gov (United States)

YOON, Ju Young; BROWN, Roger L.; BOWERS, Barbara J.; SHARKEY, Siobhan S.; HORN, Susan D.

2015-01-01

person-centered, this study did not demonstrate significant differences in ADL function changes for residents in the GH nursing homes compared to traditional nursing homes. Given that the GH model continues to evolve as it is being implemented and variations within and across GH homes are identified, large-scale longitudinal studies are needed to provide further relevant information on the effects of the GH model. PMID:26260709

Late life changes in mental health: a longitudinal study of 9683 women.

Science.gov (United States)

Leigh, Lucy; Byles, Julie E; Chojenta, Catherine; Pachana, Nancy A

2016-10-01

To identify latent subgroups of women in late life who are alike in terms of their mental health trajectories. Longitudinal data are for 9683 participants in the 1921-1926 cohort of the Australian Longitudinal Study on Women's Health, who completed at least two surveys between 1999 (aged 73-78 years) and 2008 (aged 82-87 years). Mental health was measured using the five-item mental health inventory (MHI-5). Latent profile analysis uncovered patterns of change in MHI-5 scores. Three patterns of change were identified for women who were still alive in 2008 (n = 7061), and three similar patterns for deceased women (n = 2622): (1) 'poor mental health' representing women with low MHI-5 scores, (2) 'good mental health' and (3) 'excellent' mental health, where scores remained very high. Deceased women had lower mental health scores for each class. Remote areas of residence, higher education, single marital status, higher Body Mass Index (BMI) and falls were the covariates associated with mental health in the survivor group. For the deceased group, education, BMI and falls were significant. Arthritis, stroke, heart disease, bronchitis/emphysema, diabetes and osteoporosis were associated with worse mental health for both groups, while asthma increased these odds significantly for the survivor group only. Hypertension and cancer were not significant predictors of poor mental health. The results show associations between chronic disease and level of mental health in older age, but no evidence of a large decline in mental health in the period prior to death.

Longitudinal Study of the Market Penetration of Cockpit Weather Information Systems

Science.gov (United States)

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.

Stages of Headship: A Longitudinal Study of the Principalship.

Science.gov (United States)

Weindling, Dick

This paper uses socialization theory to re-examine a unique, 10-year longitudinal study of headteachers so as to describe the stages of headship transition. It outlines prior models of leadership succession in both business and schools and produces a stage theory of headship that can be used not only as a research tool, but also as a way to assist…

Longitudinal population-based studies of affective disorders: Where to from here?

Directory of Open Access Journals (Sweden)

Beard John R

2008-09-01

Full Text Available Abstract Background Longitudinal, population-based, research is important if we are to better characterize the lifetime patterns and determinants of affective disorders. While studies of this type are becoming increasingly prevalent, there has been little discussion about the limitations of the methods commonly used. Methods Discussion paper including a brief review of key prospective population-based studies as the basis for a critical appraisal of current approaches. Results We identified a number of common methodological weaknesses that restrict the potential of longitudinal research to characterize the diversity, prognosis, and determinants of affective disorders over time. Most studies using comprehensive diagnostic instruments have either been of relatively brief duration, or have suffered from long periods between waves. Most etiologic research has focused on first onset diagnoses, although these may be relatively uncommon after early adulthood and the burden of mental disorders falls more heavily on individuals with recurring disorders. Analysis has tended to be based on changes in diagnostic status rather than anges in symptom levels, limiting study power. Diagnoses have generally been treated as homogeneous entities and few studies have explored whether diagnostic subtypes such as atypical depression vary in their etiology or prognosis. Little research has considered whether there are distinct trajectories of symptoms over time and most has focused on individual disorders such as depression, rather than considering the relationship over time between symptoms of different affective disorders. There has also been limited longitudinal research on factors in the physical or social environment that may influence the onset, recurrence or chronicity of symptoms. Conclusion Many important, and in some respects quite basic, questions remain about the trajectory of depression and anxiety disorders over the life course and the factors that

The Effects of Magnetic-Field Geometry on Longitudinal Oscillations of Solar Prominences: Cross-Sectional Area Variation for Thin Tubes

Science.gov (United States)

Luna, M.; Diaz, A. J.; Oliver, R.; Terradas, J.; Karpen, J.

2016-01-01

Solar prominences are subject to both field-aligned (longitudinal) and transverse oscillatory motions, as evidenced by an increasing number of observations. Large-amplitude longitudinal motions provide valuable information on the geometry of the filament channel magnetic structure that supports the cool prominence plasma against gravity. Our pendulum model, in which the restoring force is the gravity projected along the dipped field lines of the magnetic structure, best explains these oscillations. However, several factors can influence the longitudinal oscillations, potentially invalidating the pendulum model. Aims. The aim of this work is to study the influence of large-scale variations in the magnetic field strength along the field lines, i.e., variations of the cross-sectional area along the flux tubes supporting prominence threads. Methods. We studied the normal modes of several flux tube configurations, using linear perturbation analysis, to assess the influence of different geometrical parameters on the oscillation properties. Results. We found that the influence of the symmetric and asymmetric expansion factors on longitudinal oscillations is small.Conclusions. We conclude that the longitudinal oscillations are not significantly influenced by variations of the cross-section of the flux tubes, validating the pendulum model in this context.

Postural changes in dental hygienists. Four-year longitudinal study.

Science.gov (United States)

Barry, R M; Woodall, W R; Mahan, J M

1992-01-01

Numerous surveys identify the occurrence of musculoskeletal complaints as a concern in dentistry. However, no longitudinal data exist to indicate whether postural changes occur as a result of practicing dental hygiene. The purpose of this preliminary, four-year longitudinal study was to investigate whether any postural changes developed during the hygienists' clinical education and/or during subsequent dental hygiene practice after one and/or two years. It was anticipated that the awkward positions and intense physical demands placed on hygienists might initiate musculoskeletal problems, but that no postural changes would occur over this short period of time. Nine of 10 dental hygienists in the graduating class of 1987 were surveyed for existing musculoskeletal complaints, and the subjects were photographed for a measurement of postural change. Responses from participants indicated an increase in musculoskeletal-related complaints in each of the six areas investigated. The photographic findings indicated that one of the nine hygienists showed an increase in forward head posture, a postural change.

Reckoning HIV/AIDS care: A longitudinal study of community home ...

African Journals Online (AJOL)

To better understand the potential significance of global and national health policy/programming reliance on community health workers (task shifting), we analysed longitudinal data on both care supporter and client cohorts from 2008 to 2013. Most CHBC studies report data from only one cohort. Foremost, our analysis ...

Brief report: parenting styles and obesity in Mexican American children: a longitudinal study.

Science.gov (United States)

Olvera, Norma; Power, Thomas G

2010-04-01

To assess longitudinally the relations between four parenting styles (authoritative, authoritarian, uninvolved, and indulgent) and child weight status in Mexican American families. Sixty-nine low-income Mexican American mothers and their 4- to 8-year-old children participated in a 4-year longitudinal study. Mothers completed demographic and parenting measures. Children's body weight and height were assessed annually. Body mass index was calculated to determine weight status. At baseline, 65% of children were found to be normal weight, 14% were overweight, and 21% were obese. Analyses examined how parenting styles at baseline predicted child's weight status 3 years later, controlling for initial weight status. Children of indulgent mothers were more likely to become overweight 3 years later than children of authoritative or authoritarian mothers. This study provides longitudinal evidence for the role of indulgent parenting in predicting overweight in Mexican American children. Possible mediating factors that may account for this relationship (e.g., dietary patterns, physical activity patterns, and children's self-regulation) are considered.

A Longitudinal Study of the Determinants and Outcomes of Career Change

Science.gov (United States)

Carless, Sally A.; Arnup, Jessica L.

2011-01-01

The present longitudinal field study investigated the antecedents and consequences of an actual career change. The framework for this study was Rhodes and Doering's (1983) model of career change. We examined the effect of individual and organisational characteristics on career change behaviour. The individual characteristics were: traits (Openness…

Longitudinal Study of Body Mass Index in Young Males and the Transition to Fatherhood.

Science.gov (United States)

Garfield, Craig F; Duncan, Greg; Gutina, Anna; Rutsohn, Joshua; McDade, Thomas W; Adam, Emma K; Coley, Rebekah Levine; Chase-Lansdale, P Lindsay

2016-11-01

Despite a growing understanding that the social determinants of health have an impact on body mass index (BMI), the role of fatherhood on young men's BMI is understudied. This longitudinal study examines BMI in young men over time as they transition from adolescence into fatherhood in a nationally representative sample. Data from all four waves of the National Longitudinal Study of Adolescent Health supported a 20-year longitudinal analysis of 10,253 men beginning in 1994. A "fatherhood-year" data set was created and changes in BMI were examined based on fatherhood status (nonfather, nonresident father, resident father), fatherhood years, and covariates. Though age is positively associated with BMI over all years for all men, comparing nonresident and resident fathers with nonfathers reveals different trajectories based on fatherhood status. Entrance into fatherhood is associated with an increase in BMI trajectory for both nonresident and resident fathers, while nonfathers exhibit a decrease over the same period. In this longitudinal, population-based study, fatherhood and residence status play a role in men's BMI. Designing obesity prevention interventions for young men that begin in adolescence and carry through young adulthood should target the distinctive needs of these populations, potentially improving their health outcomes. © The Author(s) 2015.

PIV study of large-scale flow organisation in slot jets

International Nuclear Information System (INIS)

Shestakov, Maxim V.; Dulin, Vladimir M.; Tokarev, Mikhail P.; Sikovsky, Dmitrii Ph.; Markovich, Dmitriy M.

2015-01-01

Highlights: • Volumetric velocity measurements are perfumed by PIV to analyse 3D flow organisation in a slot jet. • Proper orthogonal decomposition is used to extract coherent flow motion. • Movement of quasi-two-dimensional large-scale vortices is associated with jet meandering. • Amplitude of jet meandering is found to be aperiodically modulated. • Secondary longitudinal vortex rolls are important for cross-stream mixing and momentum transfer. - Abstract: The paper reports on particle image velocimetry (PIV) measurements in turbulent slot jets bounded by two solid walls with the separation distance smaller than the jet width (5–40%). In the far-field such jets are known to manifest features of quasi-two dimensional, two component turbulence. Stereoscopic and tomographic PIV systems were used to analyse local flows. Proper orthogonal decomposition (POD) was applied to extract coherent modes of the velocity fluctuations. The measurements were performed both in the initial region close to the nozzle exit and in the far fields of the developed turbulent slot jets for Re ⩾ 10,000. A POD analysis in the initial region indicates a correlation between quasi-2D vortices rolled-up in the shear layer and local flows in cross-stream planes. While the near-field turbulence shows full 3D features, the wall-normal velocity fluctuations day out gradually due to strong wall-damping resulting in an almost two-component turbulence. On the other hand, the longitudinal vortex rolls take over to act as the main agents in wall-normal and spanwise mixing and momentum transfer. The quantitative analysis indicates that the jet meandering amplitude was aperiodically modulated when arrangement of the large-scale quasi-2D vortices changed between asymmetric and symmetric pattern relatively to the jet axis. The paper shows that the dynamics of turbulent slot jets are more complex than those of 2D, plane and rectangular 3D jets. In particular, the detected secondary longitudinal

The Sports-Related Injuries and Illnesses in Paralympic Sport Study (SRIIPSS): a study protocol for a prospective longitudinal study.

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Fagher, Kristina; Jacobsson, Jenny; Timpka, Toomas; Dahlström, Örjan; Lexell, Jan

2016-01-01

Paralympic sport provides sporting opportunities for athletes with a disability, with the Paralympic Games as the main event. Participation in sport is, however, associated with a significant risk for sustaining injuries and illnesses. Our knowledge of sports-related injuries and illnesses in Paralympic sport is very limited and there are no large-scale epidemiological cohort studies. The purpose here is to present a protocol for a prospective longitudinal study: The Sports-Related Injuries and Illnesses in Paralympic Sport Study (SRIIPSS). An argument-based method for investigation of design problems was used to structure the study protocol. The primary requirement of the protocol is to allow prospective studies over time and include exposure to both training and competition. To reflect the complexity of Paralympic sport with athletes' pre-existing impairments, use of assistive equipment, pain and other and medical issues, it is required that the data collection system is specifically adapted to Paralympic sport. To allow the collection of data, at the same time as there is limited access to coaches and medical personnel, it is advantageous that data can be collected online directly from the athletes. Based on this a self-report athlete monitoring system will be developed, where the athletes can enter data weekly via their mobile phones or lap-tops. Data will be collected from around 100 Swedish Paralympic athletes for approximately 1 year, which will allow us to i) prospectively estimate the annual incidence of sports-related injuries and illnesses and ii) explore risk factors and mechanisms for sustaining sports-related injuries and illnesses based on athlete exposure and training loads. For effective implementation of injury and illness prevention measures, comprehensive epidemiological knowledge is required. This study will be the first prospective longitudinal self-report study of sports-related injuries and illnesses in Paralympic sport over a longer period

Work-to-family conflict and its relationship with satisfaction and well-being: A one-year longitudinal study

NARCIS (Netherlands)

Kinnunen, U.; Geurts, S.A.E.; Mauno, S.

2004-01-01

The present study produced new knowledge about gender differences with respect to work-to-family conflict and its longitudinal relations with indicators of satisfaction and well-being. The study examined the longitudinal relations between work-to-family conflict and self-reported satisfaction and

High School Longitudinal Study of 2009 (HSLS:09): Base-Year Data File Documentation. NCES 2011-328

Science.gov (United States)

Ingels, Steven J.; Pratt, Daniel J.; Herget, Deborah R.; Burns, Laura J.; Dever, Jill A.; Ottem, Randolph; Rogers, James E.; Jin, Ying; Leinwand, Steve

2011-01-01

The High School Longitudinal Study of 2009 (HSLS:09) is the fifth in a series of National Center for Education Statistics (NCES) secondary longitudinal studies. The core research questions for HSLS:09 explore secondary to postsecondary transition plans and the evolution of those plans; the paths into and out of science, technology, engineering,…

Resolution of neurosensory deficit after mandibular orthognathic surgery: A prospective longitudinal study.

Science.gov (United States)

Alolayan, Albraa Badr; Leung, Yiu Yan

2017-05-01

To investigate the longitudinal resolution of neurosensory deficit (NSD) and the possible risk factors that might contribute to NSD following mandibular orthognathic procedures. A prospective longitudinal observational study on patients who had mandibular orthognathic procedures was performed. Standardized neurosensory assessments were performed. The 2 years longitudinal resolution and risk factors of NSD including patients' age and gender, specific mandibular procedures and surgeons' experience were analyzed. 66 patients (44 females) with 132 sides of mandibular procedures were enrolled in the study. Surgical procedures included mandibular ramus surgery, anterior mandibular surgery, or the combination of the two. The overall occurrences of subjective NSD improved from 78.8% at postoperative 2 weeks to 13.8% at post-operative 2 years. Combinations of ramus surgery and anterior mandibular surgery increased the risk of NSD at the first three post-operative months (p orthognathic surgery. The occurrence of NSD after mandibular orthognathic procedures reduced progressively within the post-operative 2 years. Combination of mandibular ramus surgery and anterior mandibular surgery increased the risk of NSD in the early post-operative period. Copyright © 2017 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

Diet assessment in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil: Development of a food frequency questionnaire

Directory of Open Access Journals (Sweden)

Maria del Carmen Bisi Molina

2013-04-01

Full Text Available OBJECTIVE: The objective of this article is to present the development of the Food Frequency Questionaire used in the Longitudinal Study of Adult Health-Brazil and analyze how diet exposes individuals to cardiovascular diseases and type 2 diabetes Mellitus. METHODS: The Longitudinal Study of Adult Health-Brazil dietary assessment instrument is based on a previously validated Food Frequency Questionaire and the final list of items took into consideration a study done in the six Longitudinal Study of Adult Health-Brazil investigation centers. RESULTS: New foods/preparations were included in the Food Frequency Questionaire with their respective portions, totaling 114 items. The perspectives of dietary analysis and cardiovascular diseases and diabetes are presented in Longitudinal Study of Adult Health-Brazil. CONCLUSION: A new instrument was developed to cover the regional particularities of the study population.

Psychosocial Quality-of-Life, Lifestyle and Adiposity: A Longitudinal Study in Pre-schoolers (Ballabeina Study).

Science.gov (United States)

Michels, Nathalie; Susi, Kriemler; Marques-Vidal, Pedro M; Nydegger, Andreas; Puder, Jardena J

2016-06-01

In obesity prevention, understanding psychosocial influences in early life is pivotal. Reviews reported contradictory results and a lack of longitudinal studies focusing on underlying lifestyle factors. This study tested whether psychosocial Quality-Of-Life (QOL) was associated with pre-schoolers' lifestyle and adiposity changes over one school year and whether lifestyle moderated the latter. It was hypothesised that QOL might not impact adiposity in everybody but that this might depend on preceding lifestyle. Longitudinal data from 291 Swiss pre-schoolers (initially 3.9-6.3 years) was available. The following measures were used in longitudinal regressions: psychosocial QOL by PedsQL, adiposity (BMI z-score, waist, fat%), diet (food frequency), sedentary time and accelerometer-based activity. Concerning lifestyle, low psychosocial QOL was only related to unfavourable changes in diet (less fruit β = 0.21 and more fat intake β = -0.28) and lower physical activity (β = 0.21). Longitudinal QOL-adiposity relations appeared only after moderation by lifestyle factors (beta-range 0.13-0.67). Low psychosocial QOL was associated with increased adiposity in children with an unhealthy diet intake or high sedentary time. By contrast, low psychosocial QOL was associated with decreasing adiposity in high fruit consumers or more physically active pre-schoolers. Results emphasise the need for testing moderation in the QOL-adiposity relation. An unhealthy diet can be a vulnerability factor and high physical activity a protective factor in QOL-related adiposity. Consequently, QOL and lifestyle should be targeted concurrently in multi-factorial obesity prevention. The environment should be an 'activity encouraging, healthy food zone' that minimises opportunities for stress-induced eating. In addition, appropriate stress coping skills should be acquired.

Within-subject template estimation for unbiased longitudinal image analysis.

Science.gov (United States)

Reuter, Martin; Schmansky, Nicholas J; Rosas, H Diana; Fischl, Bruce

2012-07-16

Longitudinal image analysis has become increasingly important in clinical studies of normal aging and neurodegenerative disorders. Furthermore, there is a growing appreciation of the potential utility of longitudinally acquired structural images and reliable image processing to evaluate disease modifying therapies. Challenges have been related to the variability that is inherent in the available cross-sectional processing tools, to the introduction of bias in longitudinal processing and to potential over-regularization. In this paper we introduce a novel longitudinal image processing framework, based on unbiased, robust, within-subject template creation, for automatic surface reconstruction and segmentation of brain MRI of arbitrarily many time points. We demonstrate that it is essential to treat all input images exactly the same as removing only interpolation asymmetries is not sufficient to remove processing bias. We successfully reduce variability and avoid over-regularization by initializing the processing in each time point with common information from the subject template. The presented results show a significant increase in precision and discrimination power while preserving the ability to detect large anatomical deviations; as such they hold great potential in clinical applications, e.g. allowing for smaller sample sizes or shorter trials to establish disease specific biomarkers or to quantify drug effects. Copyright © 2012 Elsevier Inc. All rights reserved.

Longitudinal effects of ionospheric responses to substorms at middle and lower latitudes: a case study

Directory of Open Access Journals (Sweden)

X. Pi

1995-08-01

Full Text Available An ionospheric model is used to simulate total electron content (TEC disturbance events observed at middle and lower latitude sites near 75°W and 7°E longitudes. Within this longitudinal range, daytime TEC disturbances show patterns that are correlated with substrom activity seen in both auroral electrojet and ring current behavior. In modeling studies of the observed ionospheric effects, both electric field and neutral wind perturbations are examined as possible mechanisms. The morphological features of the required electric field perturbations near drawn and dusk are compared with those at other times to examine the local time characteristics of magnetospheric influence. Large-scale traveling atmospheric disturbances (TADs, an alternative candidate for the disturbance source, are also characterized and compared with known thermospheric behavior.

Natural course of behavioral addictions: a 5-year longitudinal study.

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Konkolÿ Thege, Barna; Woodin, Erica M; Hodgins, David C; Williams, Robert J

2015-01-22

Resolving the theoretical controversy on the labeling of an increasing number of excessive behaviors as behavioral addictions may also be facilitated by more empirical data on these behavioral problems. For instance, an essential issue to the classification of psychiatric disorders is information on their natural course. However, longitudinal research on the chronic vs. episodic nature of behavioral addictions is scarce. The aim of the present study, therefore, was to provide data on prevalence, substance use comorbidity, and five-year trajectories of six excessive behaviors-namely exercising, sexual behavior, shopping, online chatting, video gaming, and eating. Analyses were based on the data of the Quinte Longitudinal Study, where a cohort of 4,121 adults from Ontario, Canada was followed for 5 years (2006 to 2011). The response rate was 21.3%, while retention rate was 93.9%. To assess the occurrence of each problem behavior, a single self-diagnostic question asked people whether their over-involvement in the behavior had caused significant problems for them in the past 12 months. To assess the severity of each problem behavior reported, the Behavioral Addiction Measure was administered. A mixed design ANOVA was used to investigate symptom trajectories over time for each problem behavior and whether these symptom trajectories varied as a function of sex. The large majority of people reported having problematic over-involvement for just one of these behaviors and just in a single time period. A main effect of time was found for each problem behavior, indicating a moderately strong decrease in symptom severity across time. The time x sex interaction was insignificant in each model indicating that the decreasing trend is similar for males and females. The data also showed that help seeking was very low in the case of excessive sexual behavior, shopping, online chatting, and video gaming but substantially more prevalent in the case of excessive eating and

Criminal Victimization and Crime Risk Perception: A Multilevel Longitudinal Study

Science.gov (United States)

Russo, Silvia; Roccato, Michele; Vieno, Alessio

2013-01-01

In a national sample of the Italian population, surveyed four times between October 2002 and January 2007 (N = 2,008), we performed a multilevel longitudinal study aimed at predicting the increase in crime risk perception as a function of three families of independent variables, respectively lying at the within individual level (direct…

Minor Delinquency and Immigration: A Longitudinal Study among Male Adolescents

Science.gov (United States)

Titzmann, Peter F.; Silbereisen, Rainer K.; Mesch, Gustavo

2014-01-01

On the basis of general theories of delinquency and the specific situation of immigrants, this longitudinal study investigated predictors of initial levels and rates of change in delinquency among 188 male ethnic German Diaspora immigrants from the former Soviet Union (FSU) in Germany, 237 male native German adolescents, and 182 male Jewish…

Longitudinal Study on Reciprocity between Personality Traits and Parenting Stress

Science.gov (United States)

Rantanen, Johanna; Tillemann, Kati; Metsäpelto, Riitta-Leena; Kokko, Katja; Pulkkinen, Lea

2015-01-01

Reciprocal associations between the Big Five personality traits and parenting stress--including both parents' feelings of their distress and perception of their incompetence as parents--were studied with 248 participants (49% of which were males). Longitudinal data, collected at ages 33/36, 42 and 50 years, were used. Cross-lagged path analysis…

Sports participation and psychosocial health : a longitudinal observational study in children

NARCIS (Netherlands)

Moeijes, Janet; van Busschbach, Jooske T; Bosscher, Ruud J; Twisk, Jos W R

2018-01-01

BACKGROUND: It is well known that sports participation is positively associated with psychosocial health in children, but details about this association over time are lacking. This study aimed to explore longitudinal associations between several characteristics of sports participation and three

On the infrared sensitivity of the longitudinal cross section in e+e- annihilation

International Nuclear Information System (INIS)

Beneke, M.

1996-09-01

The authors have calculated the contributions proportional to β 0 n α s n+1 to the longitudinal fragmentation function in e + e - annihilation to all orders of perturbation theory. They use this result to estimate higher-order perturbative corrections and nonperturbative corrections to the longitudinal cross section σ L and discuss the prospects of determining α s from σ L . The structure of infrared renormalons in the perturbative expansion suggests that the longitudinal cross section for hadron production with fixed momentum fraction x receives nonperturbative contributions of order 1/(x 2 Q 2 ), whereas the total cross section has a larger, 1/Q correction. This correction arises from very large longitudinal distances and is related to the behavior of the Borel integral for the cross section with fixed x at large values of the Borel parameter

A Longitudinal Analysis of Students' Motives for Communicating with Their Instructors

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Myers, Scott A.

2017-01-01

This study utilized the longitudinal survey research design using students' motives to communicate with their instructors as a test case. Participants were 282 undergraduate students enrolled in introductory communication courses at a large Mid-Atlantic university who completed the Student Communication Motives scale at three points (Time 1:…

A Longitudinal Study of the Impact of an Environmental Action

Science.gov (United States)

Rioux, Liliane; Pasquier, Daniel

2013-01-01

In a previous study, we investigated the impact of an awareness-raising campaign on the behaviour of secondary school children in the Centre Region of France, regarding the recycling of used batteries. But, was it a question of pro-environmental behaviour or simply an environmental action? To answer this question, a three-year longitudinal study…

Comparison of longitudinal excursion of a nerve-phantom model using quantitative ultrasound imaging and motion analysis system methods: A convergent validity study.

Science.gov (United States)

Paquette, Philippe; El Khamlichi, Youssef; Lamontagne, Martin; Higgins, Johanne; Gagnon, Dany H

2017-08-01

Quantitative ultrasound imaging is gaining popularity in research and clinical settings to measure the neuromechanical properties of the peripheral nerves such as their capability to glide in response to body segment movement. Increasing evidence suggests that impaired median nerve longitudinal excursion is associated with carpal tunnel syndrome. To date, psychometric properties of longitudinal nerve excursion measurements using quantitative ultrasound imaging have not been extensively investigated. This study investigates the convergent validity of the longitudinal nerve excursion by comparing measures obtained using quantitative ultrasound imaging with those determined with a motion analysis system. A 38-cm long rigid nerve-phantom model was used to assess the longitudinal excursion in a laboratory environment. The nerve-phantom model, immersed in a 20-cm deep container filled with a gelatin-based solution, was moved 20 times using a linear forward and backward motion. Three light-emitting diodes were used to record nerve-phantom excursion with a motion analysis system, while a 5-cm linear transducer allowed simultaneous recording via ultrasound imaging. Both measurement techniques yielded excellent association ( r  = 0.99) and agreement (mean absolute difference between methods = 0.85 mm; mean relative difference between methods = 7.48 %). Small discrepancies were largely found when larger excursions (i.e. > 10 mm) were performed, revealing slight underestimation of the excursion by the ultrasound imaging analysis software. Quantitative ultrasound imaging is an accurate method to assess the longitudinal excursion of an in vitro nerve-phantom model and appears relevant for future research protocols investigating the neuromechanical properties of the peripheral nerves.

Large-scale alcohol use and socioeconomic position of origin: longitudinal study from ages 15 to 19 years

DEFF Research Database (Denmark)

Andersen, Anette; Holstein, Bjørn E; Due, Pernille

2008-01-01

AIM: To examine socioeconomic position (SEP) of origin as predictor of large-scale alcohol use in adolescence. METHODS: The study population was a random sample of 15-year-olds at baseline (n=843) with a first follow-up 4 years later (n=729). Excess alcohol intake was assessed by consumption last...

Longitudinal fluctuations and decorrelation of anisotropic flow

Energy Technology Data Exchange (ETDEWEB)

Pang, Long-Gang [Frankfurt Institute for Advanced Studies, Ruth-Moufang-Strasse 1, 60438 Frankfurt am Main (Germany); Petersen, Hannah [Frankfurt Institute for Advanced Studies, Ruth-Moufang-Strasse 1, 60438 Frankfurt am Main (Germany); Institute for Theoretical Physics, Goethe University, Max-von-Laue-Strasse 1, 60438 Frankfurt am Main (Germany); GSI Helmholtzzentrum für Schwerionenforschung, Planckstr. 1, 64291 Darmstadt (Germany); Qin, Guang-You [Key Laboratory of Quark & Lepton Physics (MOE) and Institute of Particle Physics, Central China Normal University, Wuhan 430079 (China); Roy, Victor [Institute for Theoretical Physics, Goethe University, Max-von-Laue-Strasse 1, 60438 Frankfurt am Main (Germany); Wang, Xin-Nian [Key Laboratory of Quark & Lepton Physics (MOE) and Institute of Particle Physics, Central China Normal University, Wuhan 430079 (China); Nuclear Science Division MS70R0319, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States)

2016-12-15

We investigate the decorrelation of 2nd and 3rd order anisotropic flow for charged particles in two different pseudo rapidity (η) windows by varying the pseudo rapidity gap, in an event-by-event (3+1)D ideal hydrodynamic model, with fluctuating initial conditions from A Multi-Phase Transport (AMPT) model. We visualize the parton distribution at initial state for Pb+Pb collisions at LHC and Au+Au collisions at RHIC, and demonstrate the longitudinal fluctuations originating from the asymmetry between forward and backward going participants, the fluctuations of the string length and the fluctuations due to finite number of partons at different beam energies. The decorrelation of anisotropic flow of final hadrons with large η gaps is found to originate from the spatial decorrelation along the longitudinal direction in the AMPT initial conditions through hydrodynamic evolution. The agreement between our results and recent CMS data in most centralities suggests that the string-like mechanism of initial parton production in AMPT model captures the initial longitudinal fluctuation that is responsible for the measured decorrelation of anisotropic flow in Pb+Pb collisions at LHC. Our predictions for Au+Au collisions at the highest RHIC energy show stronger longitudinal decorrelation than at LHC, indicating larger longitudinal fluctuations at lower beam energies.

LONGITUDINAL STUDY OF SEMEN QUALITY AFTER INTERMITTENT EXPOSURE TO AIR POLLUTION

Science.gov (United States)

LONGITUDINAL STUDY OF SEMEN QUALITY AFTER INTERMITTENT EXPOSURE TO AIR POLLUTION. J. Rubes*, D. Zudova*, Veterinary Research Institute, Brno, CR, S.G. Selevan*, US EPA/ORD/NCEA, Washington, DC, D.P. Evenson, South Dakota State University, Brookings, SD, and S.D. Perreault, US ...

Multiple Kernel Learning with Random Effects for Predicting Longitudinal Outcomes and Data Integration

Science.gov (United States)

Chen, Tianle; Zeng, Donglin

2015-01-01

Summary Predicting disease risk and progression is one of the main goals in many clinical research studies. Cohort studies on the natural history and etiology of chronic diseases span years and data are collected at multiple visits. Although kernel-based statistical learning methods are proven to be powerful for a wide range of disease prediction problems, these methods are only well studied for independent data but not for longitudinal data. It is thus important to develop time-sensitive prediction rules that make use of the longitudinal nature of the data. In this paper, we develop a novel statistical learning method for longitudinal data by introducing subject-specific short-term and long-term latent effects through a designed kernel to account for within-subject correlation of longitudinal measurements. Since the presence of multiple sources of data is increasingly common, we embed our method in a multiple kernel learning framework and propose a regularized multiple kernel statistical learning with random effects to construct effective nonparametric prediction rules. Our method allows easy integration of various heterogeneous data sources and takes advantage of correlation among longitudinal measures to increase prediction power. We use different kernels for each data source taking advantage of the distinctive feature of each data modality, and then optimally combine data across modalities. We apply the developed methods to two large epidemiological studies, one on Huntington's disease and the other on Alzheimer's Disease (Alzheimer's Disease Neuroimaging Initiative, ADNI) where we explore a unique opportunity to combine imaging and genetic data to study prediction of mild cognitive impairment, and show a substantial gain in performance while accounting for the longitudinal aspect of the data. PMID:26177419

Specificity of the Association between Marital Discord and Longitudinal Changes in Symptoms of Depression and Generalized Anxiety Disorder in the Irish Longitudinal Study on Ageing.

Science.gov (United States)

Whisman, Mark A; Robustelli, Briana L; Labrecque, Lindsay T

2018-03-25

This longitudinal study was conducted to evaluate actor and partner effects of marital discord on changes in symptoms of depression and generalized anxiety disorder (GAD) in a large population sample of Irish adults (N = 1,445 couples), adjusting for the potential confounds of quality of other social relationships and other psychopathology symptoms. The Actor-Partner Interdependence Model was used to examine actor and partner effects of marital discord on changes in symptoms of depression and GAD at a 2-year follow-up. Additional models examined these associations adjusting for family and friend discord and symptoms of the other type of psychopathology (depressive or GAD symptoms). Actor effects of marital discord on depressive and anxiety symptoms were greater for men than for women. There were significant, positive actor effects of marital discord on depressive symptoms for husbands and wives, which remained significant when adjusting for family and friend discord and GAD symptoms. There were significant, positive actor effects of marital discord on GAD symptoms for husbands, which remained significant when adjusting for family and friend discord and depressive symptoms. Results demonstrate that longitudinal associations between marital discord and depressive symptoms (for wives and husbands) and GAD symptoms (for husbands) are incremental to other rival explanations (family and friend discord and the other set of symptoms). Findings provide evidence for a potential causal association leading from marital discord to symptoms of depression and GAD. © 2018 Family Process Institute.

Evaluation of brain ageing: a quantitative longitudinal MRI study over 7 years

Energy Technology Data Exchange (ETDEWEB)

Gracien, Rene-Maxime; Nuernberger, Lucas; Hof, Stephanie-Michelle; Reitz, Sarah C.; Hilker-Roggendorf, Ruediger; Baudrexel, Simon [Goethe University, Department of Neurology, Frankfurt/Main (Germany); Goethe University, Brain Imaging Center, Frankfurt/Main (Germany); Hok, Pavel [Goethe University, Department of Neurology, Frankfurt/Main (Germany); Goethe University, Brain Imaging Center, Frankfurt/Main (Germany); Palacky University, Department of Neurology, Olomouc (Czech Republic); Rueb, Udo [Goethe University, Dr. Senckenberg Chronomedical Institute, Frankfurt/Main (Germany); Steinmetz, Helmuth [Goethe University, Department of Neurology, Frankfurt/Main (Germany); Klein, Johannes C. [Goethe University, Department of Neurology, Frankfurt/Main (Germany); Goethe University, Brain Imaging Center, Frankfurt/Main (Germany); University of Oxford, Nuffield Department of Clinical Neurosciences, Oxford (United Kingdom); Deichmann, Ralf [Goethe University, Brain Imaging Center, Frankfurt/Main (Germany)

2017-04-15

T1 relaxometry is a promising tool for the assessment of microstructural changes during brain ageing. Previous cross-sectional studies demonstrated increasing T1 values in white and decreasing T1 values in grey matter over the lifetime. However, these findings have not yet been confirmed on the basis of a longitudinal study. In this longitudinal study over 7 years, T1 relaxometry was used to investigate the dynamics of age-related microstructural changes in older healthy subjects. T1 mapping was performed in 17 healthy subjects (range 51-77 years) at baseline and after 7 years. Advanced cortical and white matter segmentation was used to determine mean T1 values in the cortex and white matter. The analysis revealed a decrease of mean cortical T1 values over 7 years, the rate of T1 reduction being more prominent in subjects with higher age. T1 decreases were predominantly localized in the lateral frontal, parietal and temporal cortex. In contrast, mean white matter T1 values remained stable. T1 mapping is shown to be sensitive to age-related microstructural changes in healthy ageing subjects in a longitudinal setting. Data of a cohort in late adulthood and the senescence period demonstrate a decrease of cortical T1 values over 7 years, most likely reflecting decreasing water content and increased iron concentrations. (orig.)

Evaluation of brain ageing: a quantitative longitudinal MRI study over 7 years

International Nuclear Information System (INIS)

Gracien, Rene-Maxime; Nuernberger, Lucas; Hof, Stephanie-Michelle; Reitz, Sarah C.; Hilker-Roggendorf, Ruediger; Baudrexel, Simon; Hok, Pavel; Rueb, Udo; Steinmetz, Helmuth; Klein, Johannes C.; Deichmann, Ralf

2017-01-01

T1 relaxometry is a promising tool for the assessment of microstructural changes during brain ageing. Previous cross-sectional studies demonstrated increasing T1 values in white and decreasing T1 values in grey matter over the lifetime. However, these findings have not yet been confirmed on the basis of a longitudinal study. In this longitudinal study over 7 years, T1 relaxometry was used to investigate the dynamics of age-related microstructural changes in older healthy subjects. T1 mapping was performed in 17 healthy subjects (range 51-77 years) at baseline and after 7 years. Advanced cortical and white matter segmentation was used to determine mean T1 values in the cortex and white matter. The analysis revealed a decrease of mean cortical T1 values over 7 years, the rate of T1 reduction being more prominent in subjects with higher age. T1 decreases were predominantly localized in the lateral frontal, parietal and temporal cortex. In contrast, mean white matter T1 values remained stable. T1 mapping is shown to be sensitive to age-related microstructural changes in healthy ageing subjects in a longitudinal setting. Data of a cohort in late adulthood and the senescence period demonstrate a decrease of cortical T1 values over 7 years, most likely reflecting decreasing water content and increased iron concentrations. (orig.)

Simultaneous maximum a posteriori longitudinal PET image reconstruction

Science.gov (United States)

Ellis, Sam; Reader, Andrew J.

2017-09-01

Positron emission tomography (PET) is frequently used to monitor functional changes that occur over extended time scales, for example in longitudinal oncology PET protocols that include routine clinical follow-up scans to assess the efficacy of a course of treatment. In these contexts PET datasets are currently reconstructed into images using single-dataset reconstruction methods. Inspired by recently proposed joint PET-MR reconstruction methods, we propose to reconstruct longitudinal datasets simultaneously by using a joint penalty term in order to exploit the high degree of similarity between longitudinal images. We achieved this by penalising voxel-wise differences between pairs of longitudinal PET images in a one-step-late maximum a posteriori (MAP) fashion, resulting in the MAP simultaneous longitudinal reconstruction (SLR) method. The proposed method reduced reconstruction errors and visually improved images relative to standard maximum likelihood expectation-maximisation (ML-EM) in simulated 2D longitudinal brain tumour scans. In reconstructions of split real 3D data with inserted simulated tumours, noise across images reconstructed with MAP-SLR was reduced to levels equivalent to doubling the number of detected counts when using ML-EM. Furthermore, quantification of tumour activities was largely preserved over a variety of longitudinal tumour changes, including changes in size and activity, with larger changes inducing larger biases relative to standard ML-EM reconstructions. Similar improvements were observed for a range of counts levels, demonstrating the robustness of the method when used with a single penalty strength. The results suggest that longitudinal regularisation is a simple but effective method of improving reconstructed PET images without using resolution degrading priors.

A micromechanical study of porous composites under longitudinal shear and transverse normal loading

DEFF Research Database (Denmark)

Ashouri Vajari, Danial

2015-01-01

The mechanical response of porous unidirectional composites under transverse normal and longitudinal shear loading is studied using the finite element analysis. The 3D model includes discrete and random distribution of fibers and voids. The micromechanical failure mechanisms are taken into account....... Finally, the computational prediction of the porous composite in the transverse normal-longitudinal shear stress space is obtained and compared with Puck's model. The results show that both interfaces with low fracture toughness and microvoids with even small void volume fraction can significantly reduce...

A Longitudinal Study of Environmental and Outdoor Education: A Cultural Change

Science.gov (United States)

Tal, Tali; Morag, Orly

2013-01-01

In this case-study, we present a longitudinal study of one elementary (grades 1-6) school's environmental education (EE) in order to understand the ways in which the school culture supports outdoor EE as a critical component of their science education program. The school, which was known for its school-based EE curriculum that encompasses an…

The Myth of the Working Mother: Evidence from Longitudinal Data. Research Briefing No. 70

Science.gov (United States)

Joshi, Heather

2013-01-01

It has been commonly held that "children suffer if their mother goes out to work". This research uses several studies--large scale longitudinal data--to look at the development of children whose mothers were employed when those children were very young.

Children in care (CIC): A Danish longitudinal study

DEFF Research Database (Denmark)

Egelund, Tine; Hestbæk, Anne-Dorthe

This paper presents results describing what characterizes young, Danish children in care and their parents, and, furthermore, discusses social policy implications of the complex psychosocial disadvantages influencing the families. The paper is based on a longitudinal study of all Danish children......, born in 1995, who currently are or formerly have been placed in care. The first data collection was conducted in the spring 2003, where the children were 7-8 years of age. It is the intention to follow up the children every third year during childhood, adolescence, and adult life. At each new data...

Broadly Neutralizing Antibody Responses in a Large Longitudinal Sub-Saharan HIV Primary Infection Cohort.

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Elise Landais

2016-01-01

Full Text Available Broadly neutralizing antibodies (bnAbs are thought to be a critical component of a protective HIV vaccine. However, designing vaccines immunogens able to elicit bnAbs has proven unsuccessful to date. Understanding the correlates and immunological mechanisms leading to the development of bnAb responses during natural HIV infection is thus critical to the design of a protective vaccine. The IAVI Protocol C program investigates a large longitudinal cohort of primary HIV-1 infection in Eastern and South Africa. Development of neutralization was evaluated in 439 donors using a 6 cross-clade pseudo-virus panel predictive of neutralization breadth on larger panels. About 15% of individuals developed bnAb responses, essentially between year 2 and year 4 of infection. Statistical analyses revealed no influence of gender, age or geographical origin on the development of neutralization breadth. However, cross-clade neutralization strongly correlated with high viral load as well as with low CD4 T cell counts, subtype-C infection and HLA-A*03(- genotype. A correlation with high overall plasma IgG levels and anti-Env IgG binding titers was also found. The latter appeared not associated with higher affinity, suggesting a greater diversity of the anti-Env responses in broad neutralizers. Broadly neutralizing activity targeting glycan-dependent epitopes, largely the N332-glycan epitope region, was detected in nearly half of the broad neutralizers while CD4bs and gp41-MPER bnAb responses were only detected in very few individuals. Together the findings suggest that both viral and host factors are critical for the development of bnAbs and that the HIV Env N332-glycan supersite may be a favorable target for vaccine design.

How Serious of a Problem is Staff Turnover in Substance Abuse Treatment? A Longitudinal Study of Actual Turnover1

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Eby, Lillian T.; Burk, Hannah; Maher, Charleen P.

2010-01-01

In the substance abuse treatment field, the annual turnover rate is cited as being anywhere between 19 and 50 percent (Johnson & Roman, 2002; Gallon, Gabriel, & Knudsen, 2003; Knudsen et al., 2003; McLellan et al., 2003). However, no research to date has evaluated these claims by tracking turnover longitudinally using organizational turnover data from substance abuse treatment centers. This research presents the results of a longitudinal study designed to systematically examine actual turnover among counselors and clinical supervisors. Twenty-seven geographically dispersed treatment organizations, serving a wide range of clients in the public and private sector, provided data for the study over a two year time span (2008–2009). The annual turnover rate was 33.2% for counselors and 23.4% for clinical supervisors. For both groups the majority of turnover was voluntary (employee-initiated). Specific reasons for turnover were largely consistent across the two groups, with the most common reason being a new job or new opportunity. The findings are discussed in terms of the unique employment context of substance abuse treatment. Practical recommendations are also discussed to help stem the tide of turnover in the field of substance abuse treatment. PMID:20675097

The effects of the Green House nursing home model on ADL function trajectory: A retrospective longitudinal study.

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Yoon, Ju Young; Brown, Roger L; Bowers, Barbara J; Sharkey, Siobhan S; Horn, Susan D

2016-01-01

considered to represent an innovative model changing the nursing home environment into more person-centered, this study did not demonstrate significant differences in activities of daily living function changes for residents in the Green House nursing homes compared to traditional nursing homes. Given that the Green House model continues to evolve as it is being implemented and variations within and across Green House homes are identified, large-scale longitudinal studies are needed to provide further relevant information on the effects of the Green House model. Copyright © 2015 Elsevier Ltd. All rights reserved.

Grades and Graduation: A Longitudinal Risk Perspective to Identify Student Dropouts

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Bowers, Alex J.

2010-01-01

Studies of student risk of school dropout have shown that present predictors of at-risk status do not accurately identify a large percentage of students who eventually drop out. Through the analysis of the entire Grade 1-12 longitudinal cohort-based grading histories of the class of 2006 for two school districts in the United States, the author…

Functional and Structural Network Recovery after Mild Traumatic Brain Injury: A 1-Year Longitudinal Study

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Patrizia Dall’Acqua

2017-05-01

Full Text Available Brain connectivity after mild traumatic brain injury (mTBI has not been investigated longitudinally with respect to both functional and structural networks together within the same patients, crucial to capture the multifaceted neuropathology of the injury and to comprehensively monitor the course of recovery and compensatory reorganizations at macro-level. We performed a prospective study with 49 mTBI patients at an average of 5 days and 1 year post-injury and 49 healthy controls. Neuropsychological assessments as well as resting-state functional and diffusion-weighted magnetic resonance imaging were obtained. Functional and structural connectome analyses were performed using network-based statistics. They included a cross-sectional group comparison and a longitudinal analysis with the factors group and time. The latter tracked the subnetworks altered at the early phase and, in addition, included a whole-brain group × time interaction analysis. Finally, we explored associations between the evolution of connectivity and changes in cognitive performance. The early phase of mTBI was characterized by a functional hypoconnectivity in a subnetwork with a large overlap of regions involved within the classical default mode network. In addition, structural hyperconnectivity in a subnetwork including central hub areas such as the cingulate cortex was found. The impaired functional and structural subnetworks were strongly correlated and revealed a large anatomical overlap. One year after trauma and compared to healthy controls we observed a partial normalization of both subnetworks along with a considerable compensation of functional and structural connectivity subsequent to the acute phase. Connectivity changes over time were correlated with improvements in working memory, divided attention, and verbal recall. Neuroplasticity-induced recovery or compensatory processes following mTBI differ between brain regions with respect to their time course and are

Frontoparietal Structural Connectivity in Childhood Predicts Development of Functional Connectivity and Reasoning Ability: A Large-Scale Longitudinal Investigation.

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Wendelken, Carter; Ferrer, Emilio; Ghetti, Simona; Bailey, Stephen K; Cutting, Laurie; Bunge, Silvia A

2017-08-30

(functional connectivity, FC), and reasoning ability in a large longitudinal sample of subjects 6-22 years of age. We found that greater frontoparietal SC in childhood predicts future increases in both FC and reasoning ability, demonstrating the importance of white matter development during childhood for subsequent brain and cognitive functioning. Copyright © 2017 the authors 0270-6474/17/378549-10$15.00/0.

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

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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.

On the Use of Diversity Measures in Longitudinal Sequencing Studies of Microbial Communities.

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Wagner, Brandie D; Grunwald, Gary K; Zerbe, Gary O; Mikulich-Gilbertson, Susan K; Robertson, Charles E; Zemanick, Edith T; Harris, J Kirk

2018-01-01

Identification of the majority of organisms present in human-associated microbial communities is feasible with the advent of high throughput sequencing technology. As substantial variability in microbiota communities is seen across subjects, the use of longitudinal study designs is important to better understand variation of the microbiome within individual subjects. Complex study designs with longitudinal sample collection require analytic approaches to account for this additional source of variability. A common approach to assessing community changes is to evaluate the change in alpha diversity (the variety and abundance of organisms in a community) over time. However, there are several commonly used alpha diversity measures and the use of different measures can result in different estimates of magnitude of change and different inferences. It has recently been proposed that diversity profile curves are useful for clarifying these differences, and may provide a more complete picture of the community structure. However, it is unclear how to utilize these curves when interest is in evaluating changes in community structure over time. We propose the use of a bi-exponential function in a longitudinal model that accounts for repeated measures on each subject to compare diversity profiles over time. Furthermore, it is possible that no change in alpha diversity (single community/sample) may be observed despite the presence of a highly divergent community composition. Thus, it is also important to use a beta diversity measure (similarity between multiple communities/samples) that captures changes in community composition. Ecological methods developed to evaluate temporal turnover have currently only been applied to investigate changes of a single community over time. We illustrate the extension of this approach to multiple communities of interest (i.e., subjects) by modeling the beta diversity measure over time. With this approach, a rate of change in community

Delaware Longitudinal Study of Fraction Learning: Implications for Helping Children With Mathematics Difficulties.

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Jordan, Nancy C; Resnick, Ilyse; Rodrigues, Jessica; Hansen, Nicole; Dyson, Nancy

The goal of the present article is to synthesize findings to date from the Delaware Longitudinal Study of Fraction Learning. The study followed a large cohort of children ( N = 536) between Grades 3 and 6. The findings showed that many students, especially those with diagnosed learning disabilities, made minimal growth in fraction knowledge and that some showed only a basic grasp of the meaning of a fraction even after several years of instruction. Children with low growth in fraction knowledge during the intermediate grades were much more likely to fail to meet state standards on a broad mathematics measure at the end of Grade 6. Although a range of general and mathematics-specific competencies predicted fraction outcomes, the ability to estimate numerical magnitudes on a number line was a uniquely important marker of fraction success. Many children with mathematics difficulties have deep-seated problems related to whole number magnitude representations that are complicated by the introduction of fractions into the curriculum. Implications for helping students with mathematics difficulties are discussed.

Late urologic morbidity in 177 consecutive patients after radiotherapy for cervical carcinoma: a longitudinal study

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Lajer, Henrik; Thranov, Ingrid R.; Skovgaard, Lene T.; Engelholm, Svend Aa

2002-01-01

Purpose: To provide longitudinal data on urologic morbidity after radiotherapy and brachytherapy for cervical carcinoma. Methods and Materials: Five-year longitudinal urologic morbidity data were recorded from 177 consecutive patients of median age 59 years (range: 22-86 years) with cervical carcinoma receiving radiotherapy with curative intent at the Copenhagen University Hospital, Denmark. FIGO stages (%) were as follows: Stage I (15), Stage II (30), Stage III (54), and Stage IV (1). Late morbidity was calculated as cumulative incidence based on actuarial estimates. Results: The 5-year cumulative incidence based on actuarial estimates of urologic morbidity Grades 1 + 2 + 3, Grades 2 + 3, and Grade 3 were 62%, 32%, and 5%, respectively. Frequencies of urologic morbidity in the 54 recurrence-free survivors at the end of follow-up indicated some reversibility in the case of Grades 1 and 2 morbidity. Conclusion: With the longitudinal design used in the present study, a rate of mild and moderate morbidity higher than that found in most of the previously reported literature was observed, giving cause for concern and underlining the importance of further longitudinal studies on this subject, specifically studies that relate to the background urologic morbidity in the female population, as well as to the fact that urologic morbidity might regress

Perceived marginalization and aggression: a longitudinal study with low-educated adolescents.

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Issmer, Christian; Wagner, Ulrich

2015-03-01

Social exclusion can evoke aggression. In the past two decades research has demonstrated this effect both for interpersonal and societal forms of exclusion. In addition, recent violent uprisings, like the London riots in August 2011, have been linked to social exclusion in the media. However, so far there is a lack of longitudinal studies which examine the aggression-enhancing effect of societal-level exclusion (i.e., marginalization) in disadvantaged groups. This research investigates the impact of perceived marginalization on aggression in a sample of N = 181 adolescents with a low educational background by means of a two-wave longitudinal study. The results of structural equation analyses are consistent with the hypothesis that perceived marginalization enhances aggression, and that this effect is mediated by the extent of negative societal meta-stereotypes. Furthermore, the reverse path from aggression to perceptions of marginalization is also significant. We discuss the implications of these findings and highlight practical consequences. © 2014 The British Psychological Society.

A Longitudinal Study of Motivation in Foreign and Second Language Learning Context

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Ordem, Eser

2017-01-01

Although motivation has been one of the most commonly studied subjects in second and foreign language learning in recent decades, it still remains an enigma for learners and teachers. This longitudinal study aimed to follow a student (N = 1) studying German in both second and foreign language environment for three years. The study was descriptive,…

A large-scale study of epilepsy in Ecuador: methodological aspects.

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Placencia, M; Suarez, J; Crespo, F; Sander, J W; Shorvon, S D; Ellison, R H; Cascante, S M

1992-01-01

The methodology is presented of a large-scale study of epilepsy carried out in a highland area in northern Ecuador, South America, covering a population of 72,121 people; The study was carried out in two phases, the first, a cross-sectional phase, consisted of a house-to-house survey of all persons in this population, screening for epileptic seizures using a specially designed questionnaire. Possible cases identified in screening were assessed in a cascade diagnostic procedure applied by general doctors and neurologists. Its objectives were: to establish a comprehensive epidemiological profile of epileptic seizures; to describe the clinical phenomenology of this condition in the community; to validate methods for diagnosis and classification of epileptic seizures by a non-specialised team; and to ascertain the community's knowledge, attitudes and practices regarding epilepsy. A sample was selected in this phase in order to study the social aspects of epilepsy in this community. The second phase, which was longitudinal, assessed the ability of non-specialist care in the treatment of epilepsy. It consisted of a prospective clinical trial of antiepileptic therapy in untreated patients using two standard anti-epileptic drugs. Patients were followed for 12 months by a multidisciplinary team consisting of a primary health worker, rural doctor, neurologist, anthropologist, and psychologist. Standardised, reproducible instruments and methods were used. This study was carried out through co-operation between the medical profession, political agencies and the pharmaceutical industry, at an international level. We consider this a model for further large-scale studies of this type.

Evaluating the longitudinal risk of social vigilance on atherosclerosis: study protocol for the North Texas Heart Study.

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Ruiz, John M; Taylor, Daniel J; Uchino, Bert N; Smith, Timothy W; Allison, Matthew; Ahn, Chul; Johnson, Jillian J; Smyth, Joshua M

2017-08-14

Psychosocial factors are increasingly recognised as important determinants of cardiovascular disease risk. The North Texas Heart Study aims to understand the mechanisms responsible for this association with a focus on social vigilance (ie, scanning the environment for social threats). There is also growing interest in supplementing traditional methods (eg, survey assessment of psychosocial risk paired with cross-sectional and longitudinal health outcomes) with daily or repeated momentary assessment of psychosocial factors. However, there are relatively few longitudinal studies directly comparing these approaches with hard endpoints. The North Texas Heart Study proposes a longitudinal measurement burst design to examine psychosocial determinants of subclinical atherosclerosis. A sample of 300 healthy community participants, stratified by age and gender, will complete survey measures, as well as 2 days of ecological momentary assessment at baseline and at a 2-year follow-up. A range of psychosocial and behavioural factors, objective biomarkers, as well as carotid intima-media thickness (cIMT) will be assessed at both time points. Unadjusted and adjusted models will evaluate cross-sectional associations and determinants of change in the cIMT. The Institutional Review Board at the study coordinating institute (University of North Texas) has approved this study. Positive, negative or inconclusive primary and ancillary findings will be disseminated in scientific journals and conferences. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Predictors of workplace violence among ambulance personnel: a longitudinal study.

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van der Velden, Peter G; Bosmans, Mark W G; van der Meulen, Erik

2016-04-01

To examine predictors of repeated confrontations with workplace violence among ambulance personnel, the proportion of exposure to potentially traumatic events that are aggression-related and to what extent personnel was able to prevent escalations. Although previous research assessed the prevalences among this group, little is known about predictors, to what extent PTE's are WPV-related and their abilities to prevent escalations. A longitudinal study with a 6 months' time interval ( N  =   103). At T1 demographics, workplace violence and potentially traumatic events in the past year, mental health, personality, handling of rules, coping and social organizational stressors were assessed. Confrontations with aggression were also examined at T2. Multivariate logistic regression analyses showed that only problems with superiors independently predicted repeated verbal aggression and that only the (absence of the) ability to compromise very easily predicted repeatedly being on guard and repeatedly confronted with any form of aggression. Due to very low prevalences, we could not examine predictors of repeated confrontations with physical aggression ( N  =   5) and serious threat ( N  =   7). A large majority reported that in most workplace violence cases they could prevent further escalations. About 2% reported a potentially traumatic event in the year before T1 that was WPV related and perceived as very stressful.

Impaired Perception of Syllable Stress in Children with Dyslexia: A Longitudinal Study

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Goswami, Usha; Mead, Natasha; Fosker, Tim; Huss, Martina; Barnes, Lisa; Leong, Victoria

2013-01-01

Prosodic patterning is a key structural element of spoken language. However, the potential role of prosodic awareness in the phonological difficulties that characterise children with developmental dyslexia has been little studied. Here we report the first longitudinal study of sensitivity to syllable stress in children with dyslexia, enabling the…

Latino Parental Involvement in Kindergarten: Findings from the Early Childhood Longitudinal Study

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Durand, Tina M.

2011-01-01

Parental involvement in children's schooling is an important component of children's early school success. Few studies have examined this construct exclusively among Latino families. Using data from the Early Childhood Longitudinal Study (ECLS-K), the present investigation (N = 2,051) explored relations between Latino parents' home and school…

Conditions for Ubiquitous Computing: What Can Be Learned from a Longitudinal Study

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Lei, Jing

2010-01-01

Based on survey data and interview data collected over four academic years, this longitudinal study examined how a ubiquitous computing project evolved along with the changes in teachers, students, the human infrastructure, and technology infrastructure in the school. This study also investigated what conditions were necessary for successful…

Video Gaming Disorder and Sport and Exercise in Emerging Adulthood: A Longitudinal Study.

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Henchoz, Yves; Studer, Joseph; Deline, Stéphane; N'Goran, Alexandra A; Baggio, Stéphanie; Gmel, Gerhard

2016-01-01

Among the negative consequences of video gaming disorder, decreased participation in sport and exercise has received little attention. This study aimed to assess the longitudinal association between video gaming disorder and the level of sport and exercise in emerging adult men. A questionnaire was completed at baseline and 15-month follow-up by a representative national sample of 4,933 respondents. The seven items of the Game Addiction Scale were used to construct a latent variable representing video gaming disorder. Level of sport and exercise was also self-reported. Cross-lagged path modeling indicated a reciprocal causality between video gaming disorder and the level of sport and exercise, even after adjusting for a large set of confounders. These findings support the need for better promotion of sport and exercise among emerging adults in order to contribute to the prevention of video gaming disorder, and to raise the level of sport and exercise activity in addicted gamers.

Classroom Connectivity and Algebra 1 Achievement: A Three-Year Longitudinal Study

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Irving, Karen E.; Pape, Stephen J.; Owens, Douglas T.; Abrahamson, Louis; Silver, David; Sanalan, Vehbi A.

2016-01-01

Findings from three years of a longitudinal randomized control trial involving a national U.S. sample of Algebra 1 teachers and students are reported. The study examines the effects of a connected classroom technology (CCT) professional development and classroom intervention on student achievement when compared to classroom instruction with…

Weaving leadership longitudinally: a qualitative study on faculty development

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Joyce, Pauline

2015-01-01

Purpose The purpose of this study was to explore if faculty who undertake teacher preparation, which has a leadership intervention across each module, are better prepared to take on educational leadership roles. Methods A cross sectional qualitative approach was used as part of a longitudinal evaluation of a program. The aim was to explore the perceptions of a purposive sample across three cohorts of students. Data was collected via semi-structured interviews and were analyzed by thema...

A longitudinal study of structural brain network changes with normal aging

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Kai eWu

2013-04-01

Full Text Available The aim of this study was to investigate age-related changes in the topological organization of structural brain networks by applying a longitudinal design over 6 years. Structural brain networks were derived from measurements of regional gray matter volume and were constructed in age-specific groups from baseline and follow-up scans. The structural brain networks showed economical small-world properties, providing high global and local efficiency for parallel information processing at low connection costs. In the analysis of the global network properties, the local and global efficiency of the baseline scan were significantly lower compared to the follow-up scan. Moreover, the annual rate of changes in local and global efficiency showed a positive and negative quadratic correlation with the baseline age, respectively; both curvilinear correlations peaked at approximately the age of 50. In the analysis of the regional nodal properties, significant negative correlations between the annual rate of changes in nodal strength and the baseline age were found in the brain regions primarily involved in the visual and motor/ control systems, whereas significant positive quadratic correlations were found in the brain regions predominately associated with the default-mode, attention, and memory systems. The results of the longitudinal study are consistent with the findings of our previous cross-sectional study: the structural brain networks develop into a fast distribution from young to middle age (approximately 50 years old and eventually became a fast localization in the old age. Our findings elucidate the network topology of structural brain networks and its longitudinal changes, thus enhancing the understanding of the underlying physiology of normal aging in the human brain.

Leadership in transformation: a longitudinal study in a nursing organization.

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Viitala, Riitta

2014-01-01

Not only does leadership produce changes, but those changes produce leadership in organisations. The purpose of this paper is to present a theoretical and empirical analysis of the transformation of leadership at two different historical points in a health care organisation. It leans on the perspective of social constructionism, drawing especially from the ideas of Berger and Luckmann (1966). The paper seeks to improve understanding of how leaders themselves construct leadership in relation to organisational change. The empirical material was gathered in a longitudinal case study in a nursing organisation in two different historical and situational points. It consists of written narratives produced by nurse leaders that are analysed by applying discourse analysis. The empirical study revealed that the constructions of leadership were dramatically different at the two different historical and situational points. Leadership showed up as a complex, fragile and changing phenomenon, which fluctuates along with the other organisational changes. The results signal the importance of agency in leadership and the central role of "significant others". The paper questions the traditional categorisation and labelling of leadership as well as the cross-sectional studies in understanding leadership transformation. Its originality relates to the longitudinal perspective on transformation of leadership in the context of a health care organisation.

Callosal tissue loss parallels subtle decline in psychomotor speed. A longitudinal quantitative MRI study. The LADIS Study

NARCIS (Netherlands)

Jokinen, H.; Frederiksen, K.S.; Garde, E.; Skimminge, A.; Siebner, H.; Waldemar, G.; Ylikoski, R.; Madureira, S.; Verdelho, A.; van Straaten, E.C.W.; Barkhof, F.; Fazekas, F.; Schmidt, R.; Pantoni, L.; Inzitari, D.; Erkinjuntti, T.

2012-01-01

Cross-sectional studies have suggested that corpus callosum (CC) atrophy is related to impairment in global cognitive function, mental speed, and executive functions in the elderly. Longitudinal studies confirming these findings have been lacking. We investigated whether CC tissue loss is associated

Longitudinal Variation of the Lunar Tide in the Equatorial Electrojet

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Yamazaki, Yosuke; Stolle, Claudia; Matzka, Jürgen; Siddiqui, Tarique A.; Lühr, Hermann; Alken, Patrick

2017-12-01

The atmospheric lunar tide is one known source of ionospheric variability. The subject received renewed attention as recent studies found a link between stratospheric sudden warmings and amplified lunar tidal perturbations in the equatorial ionosphere. There is increasing evidence from ground observations that the lunar tidal influence on the ionosphere depends on longitude. We use magnetic field measurements from the CHAMP satellite during July 2000 to September 2010 and from the two Swarm satellites during November 2013 to February 2017 to determine, for the first time, the complete seasonal-longitudinal climatology of the semidiurnal lunar tidal variation in the equatorial electrojet intensity. Significant longitudinal variability is found in the amplitude of the lunar tidal variation, while the longitudinal variability in the phase is small. The amplitude peaks in the Peruvian sector (˜285°E) during the Northern Hemisphere winter and equinoxes, and in the Brazilian sector (˜325°E) during the Northern Hemisphere summer. There are also local amplitude maxima at ˜55°E and ˜120°E. The longitudinal variation is partly due to the modulation of ionospheric conductivities by the inhomogeneous geomagnetic field. Another possible cause of the longitudinal variability is neutral wind forcing by nonmigrating lunar tides. A tidal spectrum analysis of the semidiurnal lunar tidal variation in the equatorial electrojet reveals the dominance of the westward propagating mode with zonal wave number 2 (SW2), with secondary contributions by westward propagating modes with zonal wave numbers 3 (SW3) and 4 (SW4). Eastward propagating waves are largely absent from the tidal spectrum. Further study will be required for the relative importance of ionospheric conductivities and nonmigrating lunar tides.

Estimating search engine index size variability: a 9-year longitudinal study.

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van den Bosch, Antal; Bogers, Toine; de Kunder, Maurice

One of the determining factors of the quality of Web search engines is the size of their index. In addition to its influence on search result quality, the size of the indexed Web can also tell us something about which parts of the WWW are directly accessible to the everyday user. We propose a novel method of estimating the size of a Web search engine's index by extrapolating from document frequencies of words observed in a large static corpus of Web pages. In addition, we provide a unique longitudinal perspective on the size of Google and Bing's indices over a nine-year period, from March 2006 until January 2015. We find that index size estimates of these two search engines tend to vary dramatically over time, with Google generally possessing a larger index than Bing. This result raises doubts about the reliability of previous one-off estimates of the size of the indexed Web. We find that much, if not all of this variability can be explained by changes in the indexing and ranking infrastructure of Google and Bing. This casts further doubt on whether Web search engines can be used reliably for cross-sectional webometric studies.

Longitudinal Stability Study for the FACET-II e⁺ Damping Ring

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Bane, Karl [SLAC National Accelerator Lab., Menlo Park, CA (United States)

2016-11-29

This is an initial study of the longitudinal, single-bunch stability in the proposed FACET-II e⁺ damping ring. It is preliminary because, at present, only a few specific features of the vacuum chamber are known.

A population-based longitudinal study of risk factors for suicide attempts in major depressive disorder.

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Bolton, James M; Pagura, Jina; Enns, Murray W; Grant, Bridget; Sareen, Jitender

2010-10-01

No longitudinal study has examined risk factors for future suicide attempts in major depressive disorder in a nationally representative sample. The objective of this study was to investigate baseline sociodemographic characteristics, comorbid mental disorders, specific depressive symptoms, and previous suicidal behavior as potential risk factors for suicide attempts at 3 years follow-up. Data came from the national epidemiologic survey on alcohol and related conditions (NESARC), a large nationally representative longitudinal survey of mental illness in adults [Wave 1 (2001-2002); Wave 2 (2004-2005) n=34,653]. Logistic regression examined associations between risk factors present at Wave 1 and suicide attempts at Wave 2 (n=169) among individuals with major depressive disorder at baseline assessment (n=6004). Risk factors for incident suicide attempts at Wave 2 (n=63) were identified among those with major depressive disorder at Wave 1 and no lifetime history of suicide attempts (n=5170). Results revealed specific comorbid anxiety, personality, and substance use disorders to be associated with incident suicide attempts at Wave 2. Comorbid borderline personality disorder was strongly associated with suicide attempts in all models. Several comorbid disorders were strongly associated with suicide attempts at Wave 2 even after adjusting for previous suicidal behavior, notably posttraumatic stress disorder (adjusted odds ratio (AOR)=2.20; 95% confidence interval (95% CI) 1.27-3.83) and dependent personality disorder (AOR=4.43; 95% CI 1.93-10.18). These findings suggest that mental illness comorbidity confers an increased risk of future suicide attempts in major depressive disorder that is not solely accounted for by past suicidal behavior.

Psychological characteristics of chronic depression: a longitudinal cohort study.

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Wiersma, Jenneke E; van Oppen, Patricia; van Schaik, Digna J F; van der Does, A J Willem; Beekman, Aartjan T F; Penninx, Brenda W J H

2011-03-01

Few studies have investigated the importance of psychological characteristics for chronicity of depression. Knowledge about psychological differences between chronically depressed persons and nonchronically depressed persons may help to improve treatment of chronic depression. This is the first study to simultaneously compare in large samples various psychological characteristics between chronically depressed and nonchronically depressed adults. Baseline data were drawn from the Netherlands Study of Depression and Anxiety (NESDA), an ongoing longitudinal cohort study aimed at examining the long-term course of depressive and anxiety disorders in different health care settings and phases of illness. Participants were aged 18 to 65 years at the baseline assessment in 2004-2007 and had a current diagnosis of DSM-IV major depressive disorder (N = 1,002). Chronicity of depression was defined as being depressed for 24 months or more in the past 4 to 5 years. The chronicity criterion was fulfilled by 31% (n = 312). The NEO Five-Factor Inventory measured the 5 personality domains, the Leiden Index of Depression Sensitivity-Revised was used to measure cognitive reactivity (eg, hopelessness, rumination), and the Mastery Scale measured external locus of control. Compared to the nonchronically depressed persons, the chronically depressed persons reported significantly higher levels of neuroticism (OR = 1.81; 95% CI, 1.55-2.12; P testing these variables multivariably, the odds of chronic depression were significantly increased among those with low extraversion (OR = 0.73; 95% CI, 0.61-0.88; P = .001), high rumination (OR = 1.24; 95% CI, 1.01-1.53; P = .04), and high external locus of control (OR = 1.48; 95% CI, 1.21-1.80; P psychological characteristics for chronicity of depression. These findings provide suggestions for more specific interventions, focused on extraversion, rumination, and external locus of control, in the treatment of chronic depression. © Copyright 2011

Change in University Teachers' Elearning Beliefs and Practices: A Longitudinal Study

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Scott, Karen M.

2016-01-01

Little longitudinal research has examined change in university teachers' elearning beliefs and practices after their initial experience with elearning. This study addresses this gap by focusing on six teachers who developed and implemented an elearning resource, and the changes they made to the resource and its implementation over two years. A…

Cardiovascular events in patients with atherothrombotic disease: a population-based longitudinal study in Taiwan.

Directory of Open Access Journals (Sweden)

Wen-Hsien Lee

Full Text Available BACKGROUND: Atherothrombotic diseases including cerebrovascular disease (CVD, coronary artery disease (CAD, and peripheral arterial disease (PAD, contribute to the major causes of death in the world. Although several studies showed the association between polyvascular disease and poor cardiovascular (CV outcomes in Asian population, there was no large-scale study to validate this relationship in this population. METHODS AND RESULTS: This retrospective cohort study included patients with a diagnosis of CVD, CAD, or PAD from the database contained in the Taiwan National Health Insurance Bureau during 2001-2004. A total of 19954 patients were enrolled in this study. The atherothrombotic disease score was defined according to the number of atherothrombotic disease. The study endpoints included acute coronary syndrome (ACS, all strokes, vascular procedures, in hospital mortality, and so on. The event rate of ischemic stroke (18.2% was higher than that of acute myocardial infarction (5.7% in our patients (P = 0.0006. In the multivariate Cox regression analyses, the adjusted hazard ratios (HRs of each increment of atherothrombotic disease score in predicting ACS, all strokes, vascular procedures, and in hospital mortality were 1.41, 1.66, 1.30, and 1.14, respectively (P≦0.0169. CONCLUSIONS: This large population-based longitudinal study in patients with atherothrombotic disease demonstrated the risk of subsequent ischemic stroke was higher than that of subsequent AMI. In addition, the subsequent adverse CV events including ACS, all stroke, vascular procedures, and in hospital mortality were progressively increased as the increase of atherothrombotic disease score.

Socioeconomic gradients of cardiovascular risk factors in China and India: results from the China health and retirement longitudinal study and longitudinal aging study in India.

Science.gov (United States)

Hu, Peifeng; Wang, Serena; Lee, Jinkook

2017-09-01

Cardiovascular disease has become a major public health challenge in developing countries. The goal of this study is to compare socioeconomic status (SES) gradients of cardiovascular risk factors (CVRF) both within and between China and India. We used multivariable logistic regression models to examine the associations between SES and CVRF, using data from the China health and retirement longitudinal study and the longitudinal aging study in India. The results showed that, compared to illiteracy, the odds ratios of completing junior high school for high-risk waist circumference were 4.99 (95% confidence interval: 1.77-14.06) among Indian men, 3.42 (95% confidence interval: 1.66-7.05) among Indian women, but 0.74 (95% confidence interval: 0.59-0.92) among Chinese women. Similar patterns were observed between educational attainment and high-risk body mass index, and between education and hypertension, based on self-reported physician diagnosis and direct blood pressure measurements. SES is associated with CVRF in both China and India. However, this relationship showed opposite patterns across two countries, suggesting that this association is not fixed, but is subjective to underlying causal pathways, such as patterns of risky health behaviors and different social and health policies.

Tomographic Measurements of Longitudinal Phase Space Density

CERN Document Server

Hancock, S; McIntosh, E; Metcalf, M

1999-01-01

Tomography : the reconstruction of a two-dimensional image from a series of its one-dimensional projections is now a very broad topic with a wealth of algorithms for the reconstruction of both qualitative and quantitative images. One of the simplest algorithms has been modified to take into account the non-linearity of large-amplitude synchrotron motion in a particle accelerator. This permits the accurate reconstruction of longitudinal phase space density from one-dimensional bunch profile data. The algorithm was developed in Mathematica TM in order to exploit the extensive built-in functions and graphics. Subsequently, it has been recoded in Fortran 90 with the aim of reducing the execution time by at least a factor of one hundred. The choice of Fortran 90 was governed by the desire ultimately to exploit parallel architectures, but sequential compilation and execution have already largely yielded the required gain in speed. The use of the method to produce longitudinal phase space plots, animated sequences o...

Experimental and theoretical study of the operation of longitudinal sidewalls in reinforced concrete superstructures

Science.gov (United States)

Bokarev, Sergey; Efimov, Stefan

2017-11-01

In the present article, we report results of a laboratory experimental study of reinforced-concrete superstructure fragments with extended longitudinal boxing sidewalls. The study included laboratory tests and numerical experiments performed using a finite element model of fragments generated in specialized simulation software. The distribution of horizontal pressures over the height of longitudinal boxing sidewalls, the dependence of the bending moment in the root section of the sidewalls on the ballast-bed thickness under sleepers, and some other characteristics were examined. The results of the experimental and theoretical study have shown a good convergence of obtained data to each other and to the data obtained by an improved engineering calculation procedure proposed by the present authors.

The influence of chronic health problems on work ability and productivity at work : a longitudinal study among older employees

NARCIS (Netherlands)

Leijten, F.R.M.; Heuvel, S.G. van den; Ybema, J.F.; Beek, A.J. van der; Robroek, S.J.W.; Burdorf, A.

2014-01-01

Objectives This study aimed to assess the influence of chronic health problems on work ability and productivity at work among older employees using different methodological approaches in the analysis of longitudinal studies. Methods Data from employees, aged 45–64, of the longitudinal Study on

The influence of chronic health problems on work ability and productivity at work: A longitudinal study among older employees

NARCIS (Netherlands)

Leijten, F.R.M.; van den Heuvel, S.G.; Ybema, Jan Fekke; van der Beek, A.J.; Robroek, S.J.W.; Burdorf, A.

2014-01-01

Objectives This study aimed to assess the influence of chronic health problems on work ability and productivity at work among older employees using different methodological approaches in the analysis of longitudinal studies. Methods Data from employees, aged 45-64, of the longitudinal Study on

The influence of chronic health problems on work ability and productivity at work: a longitudinal study among older employees

NARCIS (Netherlands)

Leijten, F.R.M.; van den Heuvel, S.G.; Ybema, J.F.; van der Beek, A.J.; Robroek, S.J.W.; Burdorf, A.

2014-01-01

Objectives This study aimed to assess the influence of chronic health problems on work ability and productivity at work among older employees using different methodological approaches in the analysis of longitudinal studies. Methods Data from employees, aged 45-64, of the longitudinal Study on

Relation between birth weight and blood pressure: longitudinal study of infants and children

NARCIS (Netherlands)

L.J. Launer (Lenore); D.E. Grobbee (Diederick); A. Hofman (Albert)

1993-01-01

textabstractOBJECTIVE--To study the relation between birth weight and systolic blood pressure in infancy and early childhood. DESIGN--Longitudinal study of infants from birth to 4 years of age. SETTING--A middle class community in the Netherlands. PARTICIPANTS--476

A Longitudinal Study of Child Siblings and Theory of Mind Development

Science.gov (United States)

McAlister, Anna; Peterson, Candida

2007-01-01

This study tested a sample of 63 children twice in a longitudinal design over 14 months to examine their theory-of-mind (ToM) understanding in relation to their number of child-aged siblings (1-12 years). Age-appropriate batteries of ToM tests emphasising false belief were given at the start of the study, when children had a mean age of 4-2…

Carotid intima-media thickness in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil): a narrative review.

Science.gov (United States)

Santos, Eduardo Henrique Sena; Santos Neto, Pedro José Dos; Santos, Itamar de Souza

2018-01-01

Carotid intima-media thickness (CIMT), as measured by ultrasound, has been used in large studies as a non-invasive marker for subclinical atherosclerosis. The Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) is a cohort of 15,105 civil servants in six Brazilian cities that included CIMT evaluation in its baseline assessment. The aim of the present narrative review was to provide an overview of ELSA-Brasil CIMT articles published up to July 31, 2017. Narrative review of ELSA-Brasil CIMT studies using baseline assessment data. We searched PubMed for the terms "ELSA-Brasil" and "intima-media". This search yielded 21 published articles using CIMT data from the ELSA-Brasil baseline assessment, which were included in this review. We also present information about intima-media thickness assessment from ongoing onsite reevaluations of the study participants. Most published studies focused on the association with traditional and novel cardiovascular risk factors. Studies also presented information about the ELSA-Brasil CIMT protocol at baseline and CIMT value distribution in this large sample. Analyses on the ELSA-Brasil data led to important insights on CIMT interpretation and physiology. Besides the highlighted contributions which have already been made in this field, new data gathered during the ongoing third onsite assessment will enable investigation of substantially new research questions.

Longitudinal plasma metabolic profiles, infant feeding, and islet autoimmunity in the MIDIA study

DEFF Research Database (Denmark)

Jørgenrud, Benedicte; Stene, Lars C; Tapia, German

2017-01-01

Aims: The aim of this study was to investigate the longitudinal plasma metabolic profiles in healthy infants and the potential association with breastfeeding duration and islet autoantibodies predictive of type 1 diabetes. Method: Up to four longitudinal plasma samples from age 3 months from case......, and lower levels of methionine and 3,4-dihydroxybutyric acid at 3 months of age. Conclusions: Plasma levels of several small, polar metabolites changed with age during early childhood, independent of later islet autoimmunity status and sex. Breastfeeding was associated with higher levels of branched......-chain amino acids, and lower levels of methionine and 3,4-dihydroxybutyric acid....

The dorsal tectal longitudinal column (TLCd): a second longitudinal column in the paramedian region of the midbrain tectum.

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Aparicio, M-Auxiliadora; Saldaña, Enrique

2014-03-01

The tectal longitudinal column (TLC) is a longitudinally oriented, long and narrow nucleus that spans the paramedian region of the midbrain tectum of a large variety of mammals (Saldaña et al. in J Neurosci 27:13108-13116, 2007). Recent analysis of the organization of this region revealed another novel nucleus located immediately dorsal, and parallel, to the TLC. Because the name "tectal longitudinal column" also seems appropriate for this novel nucleus, we suggest the TLC described in 2007 be renamed the "ventral tectal longitudinal column (TLCv)", and the newly discovered nucleus termed the "dorsal tectal longitudinal column (TLCd)". This work represents the first characterization of the rat TLCd. A constellation of anatomical techniques was used to demonstrate that the TLCd differs from its surrounding structures (TLCv and superior colliculus) cytoarchitecturally, myeloarchitecturally, neurochemically and hodologically. The distinct expression of vesicular amino acid transporters suggests that TLCd neurons are GABAergic. The TLCd receives major projections from various areas of the cerebral cortex (secondary visual mediomedial area, and granular and dysgranular retrosplenial cortices) and from the medial pretectal nucleus. It densely innervates the ipsilateral lateral posterior and laterodorsal nuclei of the thalamus. Thus, the TLCd is connected with vision-related neural centers. The TLCd may be unique as it constitutes the only known nucleus made of GABAergic neurons dedicated to providing massive inhibition to higher order thalamic nuclei of a specific sensory modality.

Job Demands and Resources as Antecedents of Work Engagement: A Longitudinal Study

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Mauno, Saija; Kinnunen, Ulla; Ruokolainen, Mervi

2007-01-01

By utilizing a 2-year longitudinal design, the present study investigated the experience of work engagement and its antecedents among Finnish health care personnel (n = 409). The data were collected by questionnaires in 2003 (Time 1) and in 2005 (Time 2). The study showed that work engagement--especially vigor and dedication--was relatively…

Media Exposure, Aggression and Prosocial Behavior during Early Childhood: A Longitudinal Study

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Ostrov, Jamie M.; Gentile, Douglas A.; Crick, Nicki R.

2006-01-01

Preschool children (N = 78) enrolled in multi-informant, multi-method longitudinal study were participants in a study designed to investigate the role of media exposure (i.e., violent and educational) on concurrent and future aggressive and prosocial behavior. Specifically, the amount of media exposure and the nature of the content was used to…

Longitudinal extensive transverse myelitis (LETM) in children: A twenty-year study from Oman.

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Koul, Roshan; Alfutaisi, Amna M; Mani, Renjith; Abdel Rahim, Rana A; Sankhla, Dilip K; Al Azri, Faisal M

2017-04-01

The data on children with diagnosis of idiopathic transverse myelitis (ITM) was searched to find the pattern of myelitis in Oman. A retrospective study was carried out from January1995 to December 2014. Electronic medical records and patient medical files were seen to get the complete data of the children with ITM. This work was carried out at Sultan Qaboos University hospital, Muscat, Oman. The ethical committee of the hospital had approved the study. The diagnosis was based on the established criteria. Other causes of myelopathy were excluded. 19 children with idiopathic transverse myelitis were found. There were 18 out of 19 (94.6%) children with longitudinal extensive transverse myelitis (LETM). Longitudinal transverse extensive myelitis is the most common form of ITM in Oman.

The Prognostic Value of Left Atrial Peak Reservoir Strain in Acute Myocardial Infarction Is Dependent on Left Ventricular Longitudinal Function and Left Atrial Size

DEFF Research Database (Denmark)

Ersbøll, Mads; Andersen, Mads J; Valeur, Nana

2013-01-01

of PALS and left ventricular longitudinal strain (global longitudinal strain) in large-scale populations in regard to prognosis. METHODS AND RESULTS: We prospectively included 843 patients (mean age 62.1+/-11.8; 74% male) with acute myocardial infarction and measured global longitudinal strain, left......BACKGROUND: Peak atrial longitudinal strain (PALS) during the reservoir phase has been proposed as a measure of left atrium function in a range of cardiac conditions, with the potential for added pathophysiological insight and prognostic value. However, no studies have assessed the interrelation...

Longitudinal Surveys of Australian Youth (LSAY): 1995 Cohort: User Guide. Technical Report 49

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National Centre for Vocational Education Research (NCVER), 2009

2009-01-01

The Longitudinal Surveys of Australian Youth (LSAY) is a research program that tracks young people as they move from school into further study, work and other destinations. It uses large, nationally representative samples of young people to collect information about education and training, work, and social development. It includes surveys…

Longitudinal Bunch Position Control for the Super-B Accelerator

International Nuclear Information System (INIS)

Bertsche, Kirk; Rivetta, Claudio; Sullivam, Michael K.; SLAC; Drago, Alessandro; Frascati

2009-01-01

The use of normal conducting cavities and an ion-clearing gap will cause a significant RF accelerating voltage gap transient and longitudinal phase shift of the individual bunches along the bunch train in both rings of the SuperB accelerator. Small relative centroid position shifts between bunches of the colliding beams will have a large adverse impact on the luminosity due to the small β* y at the interaction point (IP). We investigate the possibility of minimizing the relative longitudinal position shift between bunches by reducing the gap transient in each ring and matching the longitudinal bunch positions of the two rings at the IP using feedback/feedforward techniques in the LLRF. The analysis is conducted assuming maximum use of the klystron power installed in the system

Social Strategies during University Studies Predict Early Career Work Burnout and Engagement: 18-Year Longitudinal Study

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Salmela-Aro, Katariina; Tolvanen, Asko; Nurmi, Jari-Erik

2011-01-01

This longitudinal study spanning 18 years examined the role of social strategies in early career adaptation. The aim was to find out whether individuals' social strategies measured during their university studies had an impact on work burnout and work engagement measured 10-18 years later. A sample of 292 university students completed the SAQ…

Serum albumin and muscle strength: a longitudinal study in older men and women

NARCIS (Netherlands)

Schalk, B.W.M.; Penninx, B.W.J.H.; Bouter, L.M.; Deeg, D.J.H.; Visser, M.

2005-01-01

OBJECTIVES: To examine whether low serum albumin is associated with low muscle strength and future decline in muscle strength in community-dwelling older men and women. DESIGN: Population-based cohort study. SETTING: The Longitudinal Aging Study Amsterdam. PARTICIPANTS: Six hundred seventy-six women

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

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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.,…

THE EFFECTS OF MAGNETIC-FIELD GEOMETRY ON LONGITUDINAL OSCILLATIONS OF SOLAR PROMINENCES

International Nuclear Information System (INIS)

Luna, M.; Díaz, A. J.; Karpen, J.

2012-01-01

We investigate the influence of the geometry of the solar filament magnetic structure on the large-amplitude longitudinal oscillations. A representative filament flux tube is modeled as composed of a cool thread centered in a dipped part with hot coronal regions on either side. We have found the normal modes of the system and establish that the observed longitudinal oscillations are well described with the fundamental mode. For small and intermediate curvature radii and moderate to large density contrast between the prominence and the corona, the main restoring force is the solar gravity. In this full wave description of the oscillation a simple expression for the oscillation frequencies is derived in which the pressure-driven term introduces a small correction. We have also found that the normal modes are almost independent of the geometry of the hot regions of the tube. We conclude that observed large-amplitude longitudinal oscillations are driven by the projected gravity along the flux tubes and are strongly influenced by the curvature of the dips of the magnetic field in which the threads reside.

The Effects of Magnetic-field Geometry on Longitudinal Oscillaitons of Solar Prominences

Science.gov (United States)

Luna, M.; Diaz, A. J.; Karpen, J.

2013-01-01

We investigate the influence of the geometry of the solar filament magnetic structure on the large-amplitude longitudinal oscillations. A representative filament flux tube is modeled as composed of a cool thread centered in a dipped part with hot coronal regions on either side.We have found the normal modes of the system and establish that the observed longitudinal oscillations are well described with the fundamental mode. For small and intermediate curvature radii and moderate to large density contrast between the prominence and the corona, the main restoring force is the solar gravity. In this full wave description of the oscillation a simple expression for the oscillation frequencies is derived in which the pressure-driven term introduces a small correction. We have also found that the normal modes are almost independent of the geometry of the hot regions of the tube. We conclude that observed large-amplitude longitudinal oscillations are driven by the projected gravity along the flux tubes and are strongly influenced by the curvature of the dips of the magnetic field in which the threads reside.

Longitudinal Research with Latent Variables

CERN Document Server

van Montfort, Kees; Satorra, Albert

2010-01-01

This book combines longitudinal research and latent variable research, i.e. it explains how longitudinal studies with objectives formulated in terms of latent variables should be carried out, with an emphasis on detailing how the methods are applied. Because longitudinal research with latent variables currently utilizes different approaches with different histories, different types of research questions, and different computer programs to perform the analysis, the book is divided into nine chapters. Starting from some background information about the specific approach, short history and the ma

Health and aging: development of the Irish Longitudinal Study on Ageing health assessment.

Science.gov (United States)

Cronin, Hilary; O'Regan, Clare; Finucane, Ciaran; Kearney, Patricia; Kenny, Rose Anne

2013-05-01

To assist researchers planning studies similar to The Irish Longitudinal Study on Ageing (TILDA), concerning the development of the health assessment component, to promote use of the archived data set, to inform researchers of the methods employed, and to complement the accompanying article on normative values. Prospective, longitudinal study of older adults. Republic of Ireland. Eight thousand five hundred four community-dwelling adults who participated in wave 1 of the TILDA study. The main areas of focus for the TILDA health assessments are neurocardiovascular instability, locomotion, and vision. The article describes the scientific rationale for the choice of assessments and seeks to determine the potential advantages of incorporating novel biomeasures and technologies in population-based studies to advance understanding of aging-related disorders. The detailed description of the physical measures will facilitate cross-national comparative research and put into context the normative values outlined in the subsequent article. © 2013, Copyright the Authors Journal compilation © 2013, The American Geriatrics Society.

The influence of chronic health problems on work ability and productivity at work: A longitudinal study among older employees

NARCIS (Netherlands)

F.R.M. Leijten (Fenna); S.G. van den Heuvel (Swenneke); J.F. Ybema (Jan Fekke); A.J. van der Beek (Allard); S.J.W. Robroek (Suzan); A. Burdorf (Alex)

2014-01-01

textabstractObjectives This study aimed to assess the influence of chronic health problems on work ability and productivity at work among older employees using different methodological approaches in the analysis of longitudinal studies. Methods Data from employees, aged 45-64, of the longitudinal

78 FR 44553 - Agency Information Collection Activities; Comment Request; Early Childhood Longitudinal Study...

Science.gov (United States)

2013-07-24

...) of the U.S. Department of Education (ED), is a survey that focuses on children's early school... child assessments. Like its sister study, the Early Childhood Longitudinal Study, Kindergarten Class of..., early learning, and school progress, drawing together information from multiple sources to provide rich...

Exclusive breastfeeding-Does it make a difference? : A longitudinal, prospective study of daily feeding practices, health and growth in a sample of Swedish infants

OpenAIRE

Aarts, Clara

2001-01-01

The concept of exclusive breastfeeding in relation to daily feeding practices and to health and growth of infants in an affluent society was examined. In a descriptive longitudinal prospective study 506 mother-infant pairs were followed from birth through the greater part of the first year. Feeding was recorded daily, and health and growth were recorded fortnightly. Large individual variations were seen in breastfeeding patterns. A wide discrepancy between the exclusive breastfeeding rates o...

Stable cognitive deficits in schizophrenia patients with comorbid obsessive-compulsive symptoms: a 12-month longitudinal study.

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Schirmbeck, Frederike; Rausch, Franziska; Englisch, Susanne; Eifler, Sarah; Esslinger, Christine; Meyer-Lindenberg, Andreas; Zink, Mathias

2013-11-01

Amongst schizophrenia patients, a large subgroup of up to 25% also suffers from comorbid obsessive-compulsive symptoms (OCSs). The association between comorbid OCSs in these patients and neuropsychological impairment remains unclear and somewhat contradictory. Longitudinal approaches investigating the stability of OCS-associated cognitive deficits are missing. Thirty-seven patients with schizophrenia and comorbid OCSs and 43 schizophrenia patients without OCS were assessed with a comprehensive cognitive test battery and compared at baseline and, again, 12 months later. Schizophrenia patients with comorbid OCSs showed significant pronounced deficits, with increasing effect sizes over the 12-month assessment period in specific cognitive areas such as visuospatial perception and visual memory (WAIS-R block design, Rey-Osterrieth Complex Figure Test), executive functioning (perseveration in the Wisconsin Card Sorting test), and cognitive flexibility (Trail Making test B). These cognitive domains are correlated with OCS severity and are known to be candidate cognitive domains in obsessive-compulsive disorder (OCD). OCSs in schizophrenia is associated with specific and longitudinally stable cognitive deficits, strongly arguing for at least partially overlapping neurobiological mechanisms with OCD. Prospective studies involving patients with at-risk mental states for psychosis are necessary to decipher the interaction of cognitive impairment and the clinical manifestations of schizophrenia and OCSs. This might facilitate the definition of patients at high risk for OCSs, an early detection of subclinical levels, therapeutic interventions, and clinical monitoring.

Needs and preferences among patients with high-grade glioma and their caregivers - A longitudinal mixed methods study

DEFF Research Database (Denmark)

Piil, K; Jakobsen, J; Christensen, K B

2018-01-01

Previous reports on the patient perspective of daily life during a 1-year high-grade glioma (HGG) trajectory from the time of diagnosis are sparse. The aim of this longitudinal mixed methods study is to identify the specific needs and preferences for rehabilitation and supportive care and how...... it links with physical activity, psychological measures and health quality longitudinally over the first year after diagnosis among patients with HGG and their caregivers by integrating qualitative and quantitative findings. Using a longitudinal mixed methods design, patients with malignant glioma (n = 30...

A longitudinal study of memory advantages in bilinguals.

Directory of Open Access Journals (Sweden)

Jessica K Ljungberg

Full Text Available Typically, studies of cognitive advantages in bilinguals have been conducted previously by using executive and inhibitory tasks (e.g. Simon task and applying cross-sectional designs. This study longitudinally investigated bilingual advantages on episodic memory recall, verbal letter and categorical fluency during the trajectory of life. Monolingual and bilingual participants (n=178 between 35-70 years at baseline were drawn from the Betula Prospective Cohort Study of aging, memory, and health. Results showed that bilinguals outperformed monolinguals at the first testing session and across time both in episodic memory recall and in letter fluency. No interaction with age was found indicating that the rate of change across ages was similar for bilinguals and monolinguals. As predicted and in line with studies applying cross-sectional designs, no advantages associated with bilingualism were found in the categorical fluency task. The results are discussed in the light of successful aging.

Longitudinal Study of Direct Instruction Effects from First through Third Grades

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Ryder, Randall J.; Burton, Jennifer Lyn; Silberg, Anna

2006-01-01

In a 3-year longitudinal study, the authors examined the effect of Direct Instruction (DI) on students' reading achievement, teacher perceptions, nature of the classroom, and special education referral rate. Urban and suburban students completed the Gates-MacGinitie Reading Tests in the fall of Grade 1 and spring of Grades 1, 2, and 3. Teachers…

Longitudinal and dynamic measurement invariance of the FACIT-Fatigue scale: an application of the measurement model of derivatives to ECOG-ACRIN study E2805.

Science.gov (United States)

Estabrook, Ryne; Cella, David; Zhao, Fengmin; Manola, Judith; DiPaola, Robert S; Wagner, Lynne I; Haas, Naomi B

2018-03-05

While quality of life measures may be used to assess meaningful change and group differences, their scaling and validation often rely on a single occasion of measurement. Using the 13-item FACIT-Fatigue questionnaire at three timepoints, this study tests whether individual items change together in ways consistent with a general fatigue factor. The measurement model of derivatives (MMOD) is a novel method for measurement evaluation that directly assesses whether a given factor structure accurately describes how individual test items change over time. MMOD transforms item-level longitudinal data into a set of orthogonal change scores, each one representing either a within-person longitudinal mean or a different type of longitudinal change. These change scores are then factor analyzed and tested for invariance. This approach is applied to the FACIT-Fatigue scale in a sample of patients with renal cell carcinoma treated on 'ECOG-ACRIN Cancer Research Group (ECOG-ACRIN) study 2805. Analyses revealed strong evidence of unidimensionality, and apparent factorial invariance using traditional techniques. MMOD revealed a small but statistically significant difference in factor structure ([Formula: see text], [Formula: see text]), where factor loadings were weaker and more variable for measuring longitudinal change. The differences in factor structure were not large enough to substantially affect scale usage in this application, but they do reveal some variability across items in the FACIT-Fatigue in their ability to detect change. Future applications should consider differential sensitivity of individual items in multi-item scales, and perhaps even capitalize upon these differences by selecting items that are more sensitive to change.

A longitudinal study of parenting and adolescent adjustment in Chinese adolescents with economic disadvantage.

Science.gov (United States)

Shek, Daniel T L

2003-01-01

This longitudinal study examines the relationship between parenting behavior and adolescent adjustment (psychological well-being, substance abuse and delinquent behavior) in Chinese adolescents with economic disadvantage (N = 199). Results showed that parenting characteristics were concurrently and longitudinally related to measures of adolescent adjustment, particularly adolescent problem behavior. Compared with the norm based on adolescents of a community sample, poor adolescents perceived parenting characteristics to be more negative and they had relatively lower life satisfaction. Paternal parenting was perceived to be more negative than maternal parenting and parenting behavior was perceived to deteriorate over time.

Flowing together : a longitudinal study of collective efficacy and collective flow among workgroups.

NARCIS (Netherlands)

Salanova, Marisa; Rodríguez-Sánchez, Alma M.; Schaufeli, Wilmar B.; Cifre, Eva

2014-01-01

The aim of this study is to extend the Channel Model of Flow (Csikszentmihalyi, 1975, 1990) at the collective level (workgroups) by including collective efficacy beliefs as a predictor of collective flow based on the Social Cognitive Theory (Bandura, 1997, 2001). A two-wave longitudinal lab study

What is learned from longitudinal studies of advertising and youth drinking and smoking? A critical assessment.

Science.gov (United States)

Nelson, Jon P

2010-03-01

This paper assesses the methodology employed in longitudinal studies of advertising and youth drinking and smoking behaviors. These studies often are given a causal interpretation in the psychology and public health literatures. Four issues are examined from the perspective of econometrics. First, specification and validation of empirical models. Second, empirical issues associated with measures of advertising receptivity and exposure. Third, potential endogeneity of receptivity and exposure variables. Fourth, sample selection bias in baseline and follow-up surveys. Longitudinal studies reviewed include 20 studies of youth drinking and 26 studies of youth smoking. Substantial shortcomings are found in the studies, which preclude a causal interpretation.

What is Learned from Longitudinal Studies of Advertising and Youth Drinking and Smoking? A Critical Assessment

Directory of Open Access Journals (Sweden)

Jon P. Nelson

2010-03-01

Full Text Available This paper assesses the methodology employed in longitudinal studies of advertising and youth drinking and smoking behaviors. These studies often are given a causal interpretation in the psychology and public health literatures. Four issues are examined from the perspective of econometrics. First, specification and validation of empirical models. Second, empirical issues associated with measures of advertising receptivity and exposure. Third, potential endogeneity of receptivity and exposure variables. Fourth, sample selection bias in baseline and follow-up surveys. Longitudinal studies reviewed include 20 studies of youth drinking and 26 studies of youth smoking. Substantial shortcomings are found in the studies, which preclude a causal interpretation.

A longitudinal study of school connectedness and academic outcomes across sixth grade.

Science.gov (United States)

Niehaus, Kate; Rudasill, Kathleen Moritz; Rakes, Christopher R

2012-08-01

The current longitudinal study examines the extent to which school connectedness (i.e., students' perceptions of school support and the number of adults with whom they have a positive relationship) is associated with academic outcomes across sixth grade for students from high poverty neighborhoods. Data were collected from 330 sixth-grade students attending two middle schools in a large public school district. Specifically, students completed a survey to assess their perceived connection to the school environment, and academic information regarding students' grades, attendance, and discipline referrals was obtained from school records. Results from latent growth curve modeling showed that, on average, students' perceptions of school support declined significantly across the sixth-grade year. However, students who reported less decline, or growth, in school support across sixth grade had higher academic achievement at the end of the year than students who reported more decline in school support. Sixth-grade boys were at a greater risk for negative outcomes (i.e., lower school support, lower GPAs, and more discipline referrals) across the school year than girls. Results point to the importance of perceived connectedness to school in helping economically disadvantaged students experience a safe and successful transition to middle school. Copyright © 2012 Society for the Study of School Psychology. All rights reserved.

Maternal depressive symptoms across early childhood and asthma in school children: findings from a Longitudinal Australian Population Based Study.

Science.gov (United States)

Giallo, Rebecca; Bahreinian, Salma; Brown, Stephanie; Cooklin, Amanda; Kingston, Dawn; Kozyrskyj, Anita

2015-01-01

There is a growing body of evidence attesting to links between early life exposure to stress and childhood asthma. However, available evidence is largely based on small, genetically high risk samples. The aim of this study was to explore the associations between the course of maternal depressive symptoms across early childhood and childhood asthma in a nationally representative longitudinal cohort study of Australian children. Participants were 4164 children and their biological mothers from the Longitudinal Study of Australian Children. Latent class analysis identified three trajectories of maternal depressive symptoms across four biennial waves from the first postnatal year to when children were 6-7 years: minimal symptoms (74.6%), sub-clinical symptoms (20.8%), and persistent and increasing high symptoms (4.6%). Logistic regression analyses revealed that childhood asthma at age 6-7 years was associated with persistent and increasing high depressive symptoms after accounting for known risk factors including smoking during pregnancy and maternal history of asthma (adjusted OR 2.36, 95% CI 1.61-3.45), p.001). Our findings from a nationally representative sample of Australian children provide empirical support for a relationship between maternal depressive symptoms across the early childhood period and childhood asthma. The burden of disease from childhood asthma may be reduced by strengthening efforts to promote maternal mental health in the early years of parenting.

Maternal depressive symptoms across early childhood and asthma in school children: findings from a Longitudinal Australian Population Based Study.

Directory of Open Access Journals (Sweden)

Rebecca Giallo

Full Text Available There is a growing body of evidence attesting to links between early life exposure to stress and childhood asthma. However, available evidence is largely based on small, genetically high risk samples. The aim of this study was to explore the associations between the course of maternal depressive symptoms across early childhood and childhood asthma in a nationally representative longitudinal cohort study of Australian children. Participants were 4164 children and their biological mothers from the Longitudinal Study of Australian Children. Latent class analysis identified three trajectories of maternal depressive symptoms across four biennial waves from the first postnatal year to when children were 6-7 years: minimal symptoms (74.6%, sub-clinical symptoms (20.8%, and persistent and increasing high symptoms (4.6%. Logistic regression analyses revealed that childhood asthma at age 6-7 years was associated with persistent and increasing high depressive symptoms after accounting for known risk factors including smoking during pregnancy and maternal history of asthma (adjusted OR 2.36, 95% CI 1.61-3.45, p.001. Our findings from a nationally representative sample of Australian children provide empirical support for a relationship between maternal depressive symptoms across the early childhood period and childhood asthma. The burden of disease from childhood asthma may be reduced by strengthening efforts to promote maternal mental health in the early years of parenting.

White Matter Microstructural Changes Following Quadrato Motor Training: A Longitudinal Study

Directory of Open Access Journals (Sweden)

Claudia Piervincenzi

2017-12-01

Full Text Available Diffusion tensor imaging (DTI is an important way to characterize white matter (WM microstructural changes. While several cross-sectional DTI studies investigated possible links between mindfulness practices and WM, only few longitudinal investigations focused on the effects of these practices on WM architecture, behavioral change, and the relationship between them. To this aim, in the current study, we chose to conduct an unbiased tract-based spatial statistics (TBSS analysis (n = 35 healthy participants to identify longitudinal changes in WM diffusion parameters following 6 and 12 weeks of daily Quadrato Motor Training (QMT, a whole-body mindful movement practice aimed at improving well-being by enhancing attention, coordination, and creativity. We also investigated the possible relationship between training-induced WM changes and concomitant changes in creativity, self-efficacy, and motivation. Our results indicate that following 6 weeks of daily QMT, there was a bilateral increase of fractional anisotropy (FA in tracts related to sensorimotor and cognitive functions, including the corticospinal tracts, anterior thalamic radiations, and uncinate fasciculi, as well as in the left inferior fronto-occipital, superior and inferior longitudinal fasciculi. Interestingly, significant FA increments were still present after 12 weeks of QMT in most of the above WM tracts, but only in the left hemisphere. FA increase was accompanied by a significant decrease of radial diffusivity (RD, supporting the leading role of myelination processes in training-related FA changes. Finally, significant correlations were found between training-induced diffusion changes and increased self-efficacy as well as creativity. Together, these findings suggest that QMT can improve WM integrity and support the existence of possible relationships between training-related WM microstructural changes and behavioral change.

How serious of a problem is staff turnover in substance abuse treatment? A longitudinal study of actual turnover.

Science.gov (United States)

Eby, Lillian T; Burk, Hannah; Maher, Charleen P

2010-10-01

In the substance abuse treatment field, the annual turnover rate is cited as being anywhere between 19% and 50% (J.A. Johnson & P.M. Roman, 2002; S.L. Gallon, R.M. Gabriel, J.R.W. Knudsen, 2003; H.K. Knudsen, J.A. Johnson, & P.M. Roman, 2003; A.T. McLellan, D. Carise, & H.D. Kleber, 2003). However, no research to date has evaluated these claims by tracking turnover longitudinally using organizational turnover data from substance abuse treatment centers. This research presents the results of a longitudinal study designed to systematically examine actual turnover among counselors and clinical supervisors. Twenty-seven geographically dispersed treatment organizations, serving a wide range of clients in the public and private sector, provided data for the study over a 2-year time span (2008-2009). The annual turnover rate was 33.2% for counselors and 23.4% for clinical supervisors. For both groups, the majority of turnover was voluntary (employee-initiated). Specific reasons for turnover were largely consistent across the two groups, with the most common reason being a new job or new opportunity. The findings are discussed in terms of the unique employment context of substance abuse treatment. Practical recommendations are also discussed to help stem the tide of turnover in the field of substance abuse treatment. Copyright (c) 2010 Elsevier Inc. All rights reserved.

A Longitudinal Study of Prisoners on Remand

DEFF Research Database (Denmark)

Andersen, Henrik Steen; Sestoft, Dorte; Lillebæk, Tommy

2000-01-01

Objective: To compare two levels of stress (solitary confinement (SC) and non-SC) among remand prisoners as to incidence of psychiatric disorders in relation to prevalent disorders. Method: Longitudinal repeated assessments were carried out from the start and during the remand phase of imprisonment....... Both interview-based and self-reported measures were applied to 133 remand prisoners in SC and 95 remand prisoners in non-SC randomly selected in a parallel study design. Results: Incidence of psychiatric disorders developed in the prison was significantly higher in SC prisoners (28%) than in non......-SC prisoners (15%). Most disorders were adjustment disorders, with depressive disorders coming next. Incident psychotic disorders were rare. The difference regarding incidence was primarily explained by level of stress (i.e. prison form) rather than confounding factors. Quantitative measures of psychopathology...

[Autoaggression and pulse rate--a longitudinal study].

Science.gov (United States)

Rohmann, U H; Elbing, U; Hartmann, H

1988-12-01

This article presents a model of autoaggressive behavior in which a distinction is made between determining and maintaining factors. Specific environmental, in particular social, and organismic variables are linked to them. The two types of variables interact, thus causing or maintaining autoaggressive behavior. A theory of autoaggression must therefore rely on multicausal/multimodal explanations. A connection between autoaggression and a high level of arousal suggests itself. In this single-case longitudinal study a comparison was made between heart rate and frequency of autoaggressive behavior. High heart rates were found to be correlated with low frequencies of autoaggressive behavior and vice versa. Decreasing autoaggressive behavior was coupled with increasing muscle relaxation and increasing motor activity. However, abnormally high heart rates were associated with both low and high levels of motor activity.

A longitudinal study on gross motor development in children with learning disorders

NARCIS (Netherlands)

Westendorp, Marieke; Hartman, Esther; Houwen, Suzanne; Huijgen, Barbara C. H.; Smith, Joanne; Visscher, Chris

This longitudinal study examined the development of gross motor skills, and sex-differences therein, in 7; to 11-years-old children with learning disorders (LD) and compared the results with typically developing children to determine the performance level of children with LD. In children with LD (n

Predictors of workplace violence among ambulance personnel: a longitudinal study

OpenAIRE

van der Velden, Peter G.; Bosmans, Mark W.G.; van der Meulen, Erik

2015-01-01

Abstract Aim To examine predictors of repeated confrontations with workplace violence among ambulance personnel, the proportion of exposure to potentially traumatic events that are aggression-related and to what extent personnel was able to prevent escalations. Although previous research assessed the prevalences among this group, little is known about predictors, to what extent PTE’s are WPV-related and their abilities to prevent escalations. Design A longitudinal study with a 6 months’ time ...

Parental Predictors of Children’s Shame and Guilt at Age 6 in a Multi-Method, Longitudinal Study

Science.gov (United States)

Parisette-Sparks, Alyssa; Bufferd, Sara J.; Klein, Daniel N.

2015-01-01

Objective Shame and guilt are self-conscious emotions that begin to develop early in life and are associated with various forms of psychopathology. However, little is known about the factors that contribute to these emotions in young children. Specifically, no longitudinal studies to date have examined a range of parent factors that shape the expression of children’s shame and guilt. The current multi-method, longitudinal study sought to determine whether parenting style, parental psychopathology, and parents’ marital satisfaction assessed when children were age 3 predict expressions of shame and guilt in children at age 6. Method A large community sample of families (N = 446; 87.4% Caucasian) with three-year-old children (45.7% female) was recruited through commercial mailing lists. Parent variables were assessed when children were age 3 with mother- and father-report questionnaires and a diagnostic interview. Children’s expressions of shame and guilt were observed in the laboratory at age 6. Results Fathers’, but not mothers’, history of depression and permissive parenting assessed when children were age 3 predicted children’s expressions of shame and guilt when children were age 6; parents’ marital dissatisfaction also predicted children’s shame and guilt. Conclusions These findings suggest that parents, and fathers in particular, contribute to expressions of self-conscious emotions in children. These data on emotional development may be useful for better characterizing the risk and developmental pathways of psychopathology. PMID:26538055

Longitudinal research and data collection in primary care.

NARCIS (Netherlands)

Weel, C. van

2005-01-01

PURPOSE: This article reviews examples of and experience with longitudinal research in family medicine. The objective is to use this empirical information to formulate recommendations for improving longitudinal research. METHODS: The article discusses 3 longitudinal studies from the Nijmegen

Longitudinal study of urban malaria in a cohort of Ugandan children: description of study site, census and recruitment

Directory of Open Access Journals (Sweden)

Staedke Sarah G

2006-03-01

Full Text Available Abstract Background Studies of malaria in well-defined cohorts offer important data about the epidemiology of this complex disease, but few have been done in urban African populations. To generate a sampling frame for a longitudinal study of malaria incidence and treatment in Kampala, Uganda, a census, mapping and survey project was conducted. Methods All households in a geographically defined area were enumerated and mapped. Probability sampling was used to recruit a representative sample of children and collect baseline descriptive data for future longitudinal studies. Results 16,172 residents living in 4931 households in a densely-populated community (18,824 persons/km2 were enumerated. A total of 582 households were approached with at least one child less than 10 years of age in order to recruit 601 children living in 322 households. At enrollment, 19% were parasitaemic, 24% were anaemic, 43% used bednets, and 6% used insecticide-treated nets. Low G6PD activity (OR = 0.33, P = 0.009 and bednet use (OR = 0.64, P = 0.045 were associated with a decreased risk of parasitaemia. Increasing age (OR = 0.62 for each year, P Conclusion Detailed surveys of target populations in urban Africa can provide valuable descriptive data and provide a sampling frame for recruitment of representative cohorts for longitudinal studies. Plans to use a multi-disciplinary approach to improve the understanding of the distribution and determinants of malaria incidence and response to therapy in this population are discussed.

Renal function and long-term decline in cognitive function: the Baltimore Longitudinal Study of Aging.

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Seliger, Stephen L; Wendell, Carrington R; Waldstein, Shari R; Ferrucci, Luigi; Zonderman, Alan B

2015-01-01

Renal disease has been associated with greater risk of dementia and greater cognitive impairment. However, the relationship of lower renal function with long-term decline in specific domains of cognitive function remains unclear among community-dwelling, non-demented individuals. Stroke- and dementia-free participants (n = 2,116) were enrolled in the Baltimore Longitudinal Study of Aging, a community-based, prospective, longitudinal study. Renal function was estimated by the inverse of serum creatinine adjusted for age, sex and race and (in sensitivity analyses) estimated glomerular filtration rate (eGFR) using the MDRD formula. Outcome measures were changes in scores on 6 cognitive tests encompassing a range of cognitive functions, measured at 2-year intervals. Mixed-effects regression models examined the longitudinal relations of renal function with cognitive functions after adjusting for demographics, comorbidity and other potential confounders. Mean age at initial testing was 53.9 years (SD 17.1), and 94 participants (4.4%) had an eGFR age, longitudinal increases in creatinine concentrations were associated with more rapid decline in performance on several cognitive measures, including the learning slope of the California Verbal Learning Test, a test of verbal learning (p renal function independently associated with greater long-term declines in visual memory and verbal memory and learning. © 2015 National Institutes of Health (NIH). Published by S. Karger AG, Basel.

Ten Years On: A Longitudinal Study of Families of Children with Autism.

Science.gov (United States)

Gray, David E.

2002-01-01

This paper reports results of a longitudinal, ethnographic study of the psychosocial adaptation of parents of children with autism. Most parents reported improvements in their psychological well being, the social experiences of their immediate family, and their relations with their extended family. They also reported changes in stressful…

Longitudinal patterns and predictors of multiple health risk behaviors among adolescents : the TRAILS study

NARCIS (Netherlands)

Visser, Leenke; de Winter, Andrea F.; Verhulst, Frank C.; Vollebergh, Wilma A.M.; Reijneveld, Sijmen A.

BACKGROUND: Most studies on multiple health risk behaviors among adolescents have cross-sectionally studied a limited number of health behaviors or determinants. PURPOSE: To examine the prevalence, longitudinal patterns and predictors of individual and multiple health risk behaviors among

Comparative study of longitudinal changes in peri-implant bone microstructure

International Nuclear Information System (INIS)

Suzuki, Yusuke; Matsunaga, Satoru; Abe, Shinichi; Ide, Yoshinobu; Usami, Akinobu

2010-01-01

The load applied to an implant is directly transmitted to the jaw and is considered to be one of the causes of remodeling of internal trabecular bones. However, the longitudinal changes during loading and the rearrangement of the trabecular bone structure are mostly unknown. The aim of this study was to clarify the changes in internal jaw bone structure longitudinally during natural tooth eruption as well as tooth extraction and post-implantation periods in a dog model by micro computed tomography (micro-CT). Maxillae of 16 male beagle dogs were used in this study. First, 4 dogs with all maxillary molar teeth erupted were euthanized as a control group. Next, 6 teeth consisting of the bilateral maxillary fourth premolars, and first and second molars were extracted from each of the 12 dogs. Then, 4 dogs of the tooth-extracted group were euthanized 3 months after extraction of the teeth. At this time, three implants were inserted in the left side of the maxilla of the remaining 8 dogs, and the superstructures were placed after 3 months. Four of these 8 dogs with implants were euthanized at 3 months and the other 4 at 1 year after placement of the superstructure. Then, the maxillary bone was removed from each dog as a specimen and sequential micro-CT images were taken. After reconstruction of three-dimensional images, morphological and metrical observation of the jaw trabecular bone structure was performed. A decrease of the trabecular bone in the tooth-extracted group was morphologically and morphometrically observed, whereas the implanted group showed thick, rich trabecular bone. Although a longitudinal decrease in the bone tissue volume was recognized both in the tooth-extracted and the implanted groups, the amount was smaller in the implanted group than in the tooth-extracted group. The results suggested that the application of load by implants in the case of tooth loss inhibits resorption of the alveolar bone and prevents thinning of the jaw. (author)

Burnout during nursing education predicts lower occupational preparedness and future clinical performance: a longitudinal study.

Science.gov (United States)

Rudman, Ann; Gustavsson, J Petter

2012-08-01

Early-career burnout among nurses can influence health and professional development, as well as quality of care. However, the prospective occupational consequences of study burnout have not previously been investigated in a national sample using a longitudinal design. To prospectively monitor study burnout for a national sample of nursing students during their years in higher education and at follow-up 1 year post graduation. Further, to relate the possible development of study burnout to prospective health and life outcomes, as well as student and occupational outcomes. A longitudinal cohort of Swedish nursing students (within the population-based LANE (Longitudinal Analysis of Nursing Education/Entry) study) from all sites of education in Sweden was surveyed annually. Data were collected at four points in time over 4 years: three times during higher education and 1 year post graduation. : A longitudinal sample of 1702 respondents was prospectively followed from late autumn 2002 to spring 2006. Mean level changes of study burnout (as measured by the Oldenburg Burnout Inventory, i.e. the Exhaustion and Disengagement subscales) across time, as well as prospective effects of baseline study burnout and changes in study burnout levels, were estimated using Latent Growth Curve Modeling. An increase in study burnout (from 30% to 41%) across 3 years in higher education was found, and levels of both Exhaustion and Disengagement increased significantly across the years in education (pdevelopment of study burnout, predicted lower levels of in-class learner engagement and occupational preparedness in the final year. At follow-up 1 year post graduation, earlier development of study burnout was related to lower mastery of occupational tasks, less research utilization in everyday clinical practice and higher turnover intentions. The results suggest that study burnout may have interfered with learning and psychological well-being. Aspects related to work skills and intention to

Prediction in Child Development: A Longitudinal Study of Adoptive and Nonadoptive Families. The Delaware Family Study.

Science.gov (United States)

Hoopes, Janet L.

A longitudinal study was conducted to determine factors predicting successful adoptions before placement and to identify differences and similarities between adoptive and biological families. Data collected on both adopted children and on their adoptive families before placement was related to data collected on the same children and families 6…

Evidence for a General ADHD Factor from a Longitudinal General School Population Study

Science.gov (United States)

Normand, Sebastien; Flora, David B.; Toplak, Maggie E.; Tannock, Rosemary

2012-01-01

Recent factor analytic studies in Attention-Deficit/Hyperactivity Disorder (ADHD) have shown that hierarchical models provide a better fit of ADHD symptoms than correlated models. A hierarchical model includes a general ADHD factor and specific factors for inattention, and hyperactivity/impulsivity. The aim of this 12-month longitudinal study was…

The HAPPY study (Holistic Approach to Pregnancy and the first Postpartum Year): design of a large prospective cohort study.

Science.gov (United States)

Truijens, Sophie E M; Meems, Margreet; Kuppens, Simone M I; Broeren, Maarten A C; Nabbe, Karin C A M; Wijnen, Hennie A; Oei, S Guid; van Son, Maarten J M; Pop, Victor J M

2014-09-08

The HAPPY study is a large prospective longitudinal cohort study in which pregnant women (N ≈ 2,500) are followed during the entire pregnancy and the whole first year postpartum. The study collects a substantial amount of psychological and physiological data investigating all kinds of determinants that might interfere with general well-being during pregnancy and postpartum, with special attention to the effect of maternal mood, pregnancy-related somatic symptoms (including nausea and vomiting (NVP) and carpal tunnel syndrome (CTS) symptoms), thyroid function, and human chorionic gonadotropin (HCG) on pregnancy outcome of mother and foetus. During pregnancy, participants receive questionnaires at 12, 22 and 32 weeks of gestation. Apart from a previous obstetric history, demographic features, distress symptoms, and pregnancy-related somatic symptoms are assessed. Furthermore, obstetrical data of the obstetric record form and ultrasound data are collected during pregnancy. At 12 and 30 weeks, thyroid function is assessed by blood analysis of thyroid stimulating hormone (TSH), free thyroxine (FT4) and thyroid peroxidase antibodies (TPO-Ab), as well as HCG. Also, depression is assessed with special focus on the two key symptoms: depressed mood and anhedonia. After childbirth, cord blood, neonatal heel screening results and all obstetrical data with regard to start of labour, mode of delivery and complications are collected. Moreover, mothers receive questionnaires at one week, six weeks, four, eight, and twelve months postpartum, to investigate recovery after pregnancy and delivery, including postpartum mood changes, emotional distress, feeding and development of the newborn. The key strength of this large prospective cohort study is the holistic (multifactorial) approach on perinatal well-being combined with a longitudinal design with measurements during all trimesters of pregnancy and the whole first year postpartum, taking into account two physiological possible

Family Structure and Childhood Obesity, Early Childhood Longitudinal Study ? Kindergarten Cohort

OpenAIRE

Chen, Alex Y.; Escarce, Jos? J.

2010-01-01

Introduction Little is known about the effect of family structure on childhood obesity among US children. This study examines the effect of number of parents and number of siblings on children's body mass index and risk of obesity. Methods We conducted a secondary data analysis of the Early Childhood Longitudinal Study ? Kindergarten Cohort (ECLS-K), which consists of a nationally representative cohort of children who entered kindergarten during 1998-1999. Our analyses included 2 cross-sectio...

A qualitative study of participants' views on re-consent in a longitudinal biobank.

Science.gov (United States)

Dixon-Woods, Mary; Kocman, David; Brewster, Liz; Willars, Janet; Laurie, Graeme; Tarrant, Carolyn

2017-03-23

Biomedical research increasingly relies on long-term studies involving use and re-use of biological samples and data stored in large repositories or "biobanks" over lengthy periods, often raising questions about whether and when a re-consenting process should be activated. We sought to investigate the views on re-consent of participants in a longitudinal biobank. We conducted a qualitative study involving interviews with 24 people who were participating in a longitudinal biobank. Their views were elicited using a semi-structured interview schedule and scenarios based on a hypothetical biobank. Data analysis was based on the constant comparative method. What participants identified as requiring new consent was not a straightforward matter predictable by algorithms about the scope of the consent, but instead was contingent. They assessed whether proposed new research implied a fundamental alteration in the underlying character of the biobank and whether specific projects were within the scope of the original consent. What mattered most to them was that the cooperative bargain into which they had entered was maintained in good faith. They saw re-consent as one important safeguard in this bargain. In determining what required re-consent, they deployed two logics. First, they used a logic of boundaries, where they sought to detect any possible rupture with their existing framework of cooperation. Second, they used a logic of risk, where they assessed proposed research for any potential threats for them personally or the research endeavour. When they judged that a need for re-consent had been activated, participants saw the process as way of re-actualising and renewing the cooperative bargain. Participants' perceptions of research as a process of mutual co-operation between volunteer and researcher were fundamental to their views on consent. Consenting arrangements for biobanks should respect the cooperative values that are important to participants, recognise the two

Attention Problems in Very Preterm Children from Childhood to Adulthood: The Bavarian Longitudinal Study

Science.gov (United States)

Breeman, Linda D.; Jaekel, Julia; Baumann, Nicole; Bartmann, Peter; Wolke, Dieter

2016-01-01

Background: Very preterm (VP; gestational age attention problems in childhood and adulthood. The stability of these problems into adulthood is not known. Methods: The Bavarian Longitudinal Study is a prospective cohort study that followed 260 VP/VLBW and 229 term-born…

FEAST 3.1: finite-element modeling of sheath deformation such as longitudinal ridging and collapse into axial gap

Energy Technology Data Exchange (ETDEWEB)

Wang, X.; Xu, Z.; Kim, Y-S.; Lai, L.; Cheng, G.; Xu, S. [Atomic Energy of Canada Limited, Mississauga, Ontario (Canada)

2010-07-01

During normal operation, the collapsible CANDU® fuel sheath deforms, especially, it may deform into longitudinal ridges or collapse instantaneously into the axial gaps between the end pellet and endcap or between two neighbouring pellets. These phenomena occur under certain conditions, such as the coolant pressure exceeding critical pressures for longitudinal ridging or axial collapse. Both longitudinal ridging and axial collapse phenomena result from plastic instability in the sheath under coolant pressure. Longitudinal ridging features one or multiple lobes or 'ridges' (outward from the sheath surface) formed along the sheath in the longitudinal direction. Axial collapse features a 'valley' around the sheath circumference. Both phenomena can lead to sheath overstrain, which in turn potentially leads to sheath failure. The LONGER code, which contains empirical correlations, has been used to predict the critical pressures for these two sheath deformation phenomena. To study fuel behaviour outside of the application ranges of the LONGER empirical correlations, a mechanistic model is needed. FEAST (Finite Element Analysis for Stresses) is an AECL computer code used to assess the structural integrity of the CANDU fuel element. The FEAST code has recently been developed (to Version 3.1) to model processes occurring during longitudinal ridge formation and instantaneous collapse into the axial gap. The new models include those for geometric non-linearity (large deformation, large material rotation), non-linear stress-strain curve for plastic deformation, Zr-4 sheath creep law, and variable Young’s Modulus etc. This paper describes the mechanistic model (FEAST 3.1) development for analyses of longitudinal ridging and instantaneous collapse into axial gap, and the comparison with the results from empirical correlations in LONGER. (author)

FEAST 3.1: finite-element modeling of sheath deformation such as longitudinal ridging and collapse into axial gap

International Nuclear Information System (INIS)

Wang, X.; Xu, Z.; Kim, Y-S.; Lai, L.; Cheng, G.; Xu, S.

2010-01-01

During normal operation, the collapsible CANDU® fuel sheath deforms, especially, it may deform into longitudinal ridges or collapse instantaneously into the axial gaps between the end pellet and endcap or between two neighbouring pellets. These phenomena occur under certain conditions, such as the coolant pressure exceeding critical pressures for longitudinal ridging or axial collapse. Both longitudinal ridging and axial collapse phenomena result from plastic instability in the sheath under coolant pressure. Longitudinal ridging features one or multiple lobes or 'ridges' (outward from the sheath surface) formed along the sheath in the longitudinal direction. Axial collapse features a 'valley' around the sheath circumference. Both phenomena can lead to sheath overstrain, which in turn potentially leads to sheath failure. The LONGER code, which contains empirical correlations, has been used to predict the critical pressures for these two sheath deformation phenomena. To study fuel behaviour outside of the application ranges of the LONGER empirical correlations, a mechanistic model is needed. FEAST (Finite Element Analysis for Stresses) is an AECL computer code used to assess the structural integrity of the CANDU fuel element. The FEAST code has recently been developed (to Version 3.1) to model processes occurring during longitudinal ridge formation and instantaneous collapse into the axial gap. The new models include those for geometric non-linearity (large deformation, large material rotation), non-linear stress-strain curve for plastic deformation, Zr-4 sheath creep law, and variable Young’s Modulus etc. This paper describes the mechanistic model (FEAST 3.1) development for analyses of longitudinal ridging and instantaneous collapse into axial gap, and the comparison with the results from empirical correlations in LONGER. (author)

HbA1c, diabetes and cognitive decline: the English Longitudinal Study of Ageing.

Science.gov (United States)

Zheng, Fanfan; Yan, Li; Yang, Zhenchun; Zhong, Baoliang; Xie, Wuxiang

2018-04-01

The aim of the study was to evaluate longitudinal associations between HbA 1c levels, diabetes status and subsequent cognitive decline over a 10 year follow-up period. Data from wave 2 (2004-2005) to wave 7 (2014-2015) of the English Longitudinal Study of Ageing (ELSA) were analysed. Cognitive function was assessed at baseline (wave 2) and reassessed every 2 years at waves 3-7. Linear mixed models were used to evaluate longitudinal associations. The study comprised 5189 participants (55.1% women, mean age 65.6 ± 9.4 years) with baseline HbA 1c levels ranging from 15.9 to 126.3 mmol/mol (3.6-13.7%). The mean follow-up duration was 8.1 ± 2.8 years and the mean number of cognitive assessments was 4.9 ± 1.5. A 1 mmol/mol increment in HbA 1c was significantly associated with an increased rate of decline in global cognitive z scores (-0.0009 SD/year, 95% CI -0.0014, -0.0003), memory z scores (-0.0005 SD/year, 95% CI -0.0009, -0.0001) and executive function z scores (-0.0008 SD/year, 95% CI -0.0013, -0.0004) after adjustment for baseline age, sex, total cholesterol, HDL-cholesterol, triacylglycerol, high-sensitivity C-reactive protein, BMI, education, marital status, depressive symptoms, current smoking, alcohol consumption, hypertension, CHD, stroke, chronic lung disease and cancer. Compared with participants with normoglycaemia, the multivariable-adjusted rate of global cognitive decline associated with prediabetes and diabetes was increased by -0.012 SD/year (95% CI -0.022, -0.002) and -0.031 SD/year (95% CI -0.046, -0.015), respectively (p for trend cognitive decline with diabetes. Significant longitudinal associations between HbA 1c levels, diabetes status and long-term cognitive decline were observed in this study. Future studies are required to determine the effects of maintaining optimal glucose control on the rate of cognitive decline in people with diabetes.

Longitudinal study on reciprocity between personality traits and parenting stress

OpenAIRE

Rantanen, Johanna; Tillemann, Kati; Metsäpelto, Riitta-Leena; Kokko, Katja; Pulkkinen, Lea

2014-01-01

Reciprocal associations between the Big Five personality traits and parenting stress—including both parents’ feelings of their distress and perception of their incompetence as parents—were studied with 248 participants (49% of which were males). Longitudinal data, collected at ages 33/36, 42 and 50 years, were used. Cross-lagged path analysis revealed that in case of both mothers and fathers, neuroticism at age 33 predicted high parenting stress, and extraversion at age 33 predicted low paren...

The Effects of Education on Business Ownership: A Longitudinal Study of Women.

Science.gov (United States)

Dolinsky, Arthur L.; And Others

1993-01-01

A study using a national longitudinal sample of women to examine variations in the likelihood of entering, staying, and reentering self-employment by level of educational attainment found that each likelihood increased with increasing levels of education. Differences in the likelihood of entry accounted for most of the overall difference between…

A Longitudinal Study of Changes in Marketing Practices at Private Christian Colleges

Science.gov (United States)

Vander Schee, Brian A.

2009-01-01

This article presents the results of a longitudinal study investigating current marketing practices at selected church-related, private, four-year compared to those in place in 1997. The role that institutional selectivity plays in the use of marketing activities was also investigated. The researcher surveyed the admissions directors or enrollment…

Stability and Change in Work Values: A Meta-Analysis of Longitudinal Studies

Science.gov (United States)

Jin, Jing; Rounds, James

2012-01-01

A meta-analysis of longitudinal studies was conducted to investigate stability and change in work values across the life span. Both rank-order stability and mean-level change were investigated using an integrative classification for intrinsic, extrinsic, social and status work values (Ross, Schwartz, & Surkis, 1999). Results of rank-order…

The Importance of Additive Reasoning in Children's Mathematical Achievement: A Longitudinal Study

Science.gov (United States)

Ching, Boby Ho-Hong; Nunes, Terezinha

2017-01-01

This longitudinal study examines the relative importance of counting ability, additive reasoning, and working memory in children's mathematical achievement (calculation and story problem solving). In Hong Kong, 115 Chinese children aged 6 years old participated in 2 waves of assessments (T1 = first grade and T2 = second grade). Multiple regression…

A Longitudinal Study of the Relation between Depressive Symptomatology and Parenting Practices

Science.gov (United States)

Arellano, Paula A. Errazuriz; Harvey, Elizabeth A.; Thakar, Dhara A.

2012-01-01

This longitudinal study examined whether mothers' depressive symptomatology predicted parenting practices in a sample of 199 mothers of 3-year-old children with behavior problems who were assessed yearly until age 6. Higher maternal depressive symptoms were associated with higher overreactivity and laxness and lower warmth when children were 6…

Qualitative approaches to large scale studies and students' achievements in Science and Mathematics - An Australian and Nordic Perspective

DEFF Research Database (Denmark)

Davidsson, Eva; Sørensen, Helene

Large scale studies play an increasing role in educational politics and results from surveys such as TIMSS and PISA are extensively used in medial debates about students' knowledge in science and mathematics. Although this debate does not usually shed light on the more extensive quantitative...... analyses, there is a lack of investigations which aim at exploring what is possible to conclude or not to conclude from these analyses. There is also a need for more detailed discussions about what trends could be discern concerning students' knowledge in science and mathematics. The aim of this symposium...... is therefore to highlight and discuss different approaches to how data from large scale studies could be used for additional analyses in order to increase our understanding of students' knowledge in science and mathematics, but also to explore possible longitudinal trends, hidden in the data material...

Longitudinal predictors of health-related quality of life in middle-aged and older adults with hypertension: results of a population-based study.

Science.gov (United States)

Maatouk, Imad; Wild, Beate; Herzog, Wolfgang; Wesche, Daniela; Schellberg, Dieter; Schöttker, Ben; Müller, Heiko; Rothenbacher, Dietrich; Stegmaier, Christa; Brenner, Hermann

2012-07-01

The aim of the study was to assess the longitudinal association between cardiovascular risk factors including albuminuria and other variables (e.g. awareness of hypertension, number of types of antihypertensive drugs, comorbidity), and health-related quality of life (HRQOL) in a large cohort of patients with hypertension, over a follow-up period of 5 years. Nine thousand nine hundred and fifty-three participants of the ESTHER (Epidemiologische Studie zu Chancen der Verhütung, Früherkennung und optimierten Therapie chronischer Erkrankungen) study - a population-based cohort study of middle-aged and older adults aged 50-74 years at baseline - were recruited by general practitioners (GPs) in 2000-2002 and included in the follow-up (2005-2007). HRQOL at baseline and follow-up was measured using the Short-Form General Health Survey (SF-12). Mental component scores (MCS) and physical component scores (PCS) were calculated. Multiple linear regression models were used to determine longitudinal predictors of HRQOL at follow-up. Four thousand, two hundred and three patients with hypertension (98.2%) responded to the SF-12 both at baseline and after 5 years and were therefore included in the study. Smoking status, BMI, diabetes, macroalbuminuria, comorbid diseases, history of depression, and lower HRQOL at baseline predicted lower PCS at the 5-year follow-up. Lower MCS after 5 years was predicted by smoking status, dyslipidaemia, a reported history of depression, and HRQOL at baseline. No significant association was detected between awareness of hypertension and any HRQOL component score after 5 years. Macroalbuminuria and other variables related to increased cardiovascular risk have a negative impact on PCS. Suggestions of a link of treatment and awareness of hypertension with HRQOL from previous cross-sectional studies are not supported by our longitudinal findings.

Longitudinal assessment of cerebral 5-HT{sub 2A} receptors in healthy elderly volunteers: an [{sup 18}F]-altanserin PET study

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Marner, Lisbeth; Knudsen, Gitte M.; Haugboel, Steven [University Hospital Rigshospitalet, Neurobiology Research Unit, N9201, Copenhagen O (Denmark); Holm, Soeren [Rigshospitalet, PET and Cyclotron Unit, Department of Clinical Physiology and Nuclear Medicine, Copenhagen (Denmark); Baare, William [Hvidovre Hospital, Danish Research Center for Magnetic Resonance, Copenhagen (Denmark); Hasselbalch, Steen G. [University Hospital Rigshospitalet, Neurobiology Research Unit, N9201, Copenhagen O (Denmark)]|[Memory Disorders Research Unit, The Neuroscience Center, Copenhagen (Denmark)

2009-02-15

The serotonin 2A (5-HT{sub 2A}) receptor is of interest in several psychiatric and neurological diseases. In the present study we investigated the longitudinal stability of 5-HT{sub 2A} receptors and the stability of the quantification procedure in the elderly in order to be able to study elderly patients with neuropsychiatric diseases on a longitudinal basis. [{sup 18}F]-Altanserin PET was used to quantify 5-HT{sub 2A} receptors in 12 healthy elderly individuals at baseline and at 2 years in six volumes of interest. A bolus/infusion protocol was used to achieve the binding potential, BP{sub P}. The reproducibility as assessed in terms of variability and the reliability as assessed in terms of intraclass correlation coefficient (ICC) were used to compare inter- and intraobserver stability and to evaluate the effects of increasing complexity of partial volume (PV) corrections. We also compared the stability of our measurements over 2 years with the stability of data from an earlier study with 2-week test-retest measurements. BP{sub P} was unaltered at follow-up without the use of PV correction and when applying two-tissue PV correction, test-retest reproducibility was 12-15% and reliability 0.45-0.67 in the large bilateral regions such as the parietal, temporal, occipital and frontal cortices, while orbitofrontal and anterior cingulate cortical regions were less stable. The use of PV correction decreased the variability but also decreased the between-subject variation, thereby worsening the reliability. In healthy elderly individuals, brain 5-HT{sub 2A} receptor binding remains stable over 2 years, and acceptable reproducibility and reliability in larger regions and high intra- and interobserver stability allow the use of [{sup 18}F]-altanserin in longitudinal studies of patients with neuropsychiatric disorders. (orig.)

Time Pressure, Time Autonomy, and Sickness Absenteeism in Hospital Employees: A Longitudinal Study on Organizational Absenteeism Records

OpenAIRE

Maria U. Kottwitz; Volker Schade; Christian Burger; Lorenz Radlinger; Achim Elfering

2018-01-01

Background: Although work absenteeism is in the focus of occupational health, longitudinal studies on organizational absenteeism records in hospital work are lacking. This longitudinal study tests time pressure and lack of time autonomy to be related to higher sickness absenteeism. Methods: Data was collected for 180 employees (45% nurses) of a Swiss hospital at baseline and at follow-up after 1 year. Absent times (hours per month) were received from the human resources department of the hosp...

Gastrocnemius muscle contracture after spinal cord injury: a longitudinal study.

Science.gov (United States)

Diong, Joanna; Harvey, Lisa A; Kwah, Li Khim; Clarke, Jillian L; Bilston, Lynne E; Gandevia, Simon C; Herbert, Robert D

2013-07-01

The aim of this study was to examine changes in passive length and stiffness of the gastrocnemius muscle-tendon unit in people after spinal cord injury. In a prospective longitudinal study, eight wheelchair-dependent participants with severe paralysis were assessed 3 and 12 mos after spinal cord injury. Passive torque-angle data were obtained as the ankle was slowly rotated through range at six knee angles. Differences in passive ankle torque-angle data recorded at different knee angles were used to derive passive length-tension curves of the gastrocnemius muscle-tendon unit. Ultrasound imaging was used to determine fascicle and tendon contributions to the muscle-tendon unit length-tension curves. The participants had ankle contractures (mean [SD] maximum passive ankle dorsiflexion angle, 88 [9] degrees) 3 mos after spinal cord injury. Ankle range did not worsen significantly during the subsequent 9 mos (mean change, -5 degrees; 95% confidence interval, -16 to 6 degrees). There were no changes in the mean slack length or the stiffness of the gastrocnemius muscle-tendon unit or in the slack lengths of the fascicles or the tendon between 3 and 12 mos after spinal cord injury. There were no consistent patterns of the change in slack length or stiffness with the changes in ankle range in the data from the individual participants. This study, the first longitudinal study of muscle length and stiffness after spinal cord injury, showed that the length and the stiffness of the gastrocnemius did not change substantially between 3 and 12 mos after injury.

A longitudinal study of adult foreign language learning

DEFF Research Database (Denmark)

Nielsen, Andreas Højlund; Horn, Nynne Thorup; Sørensen, Stine Derdau

Models of speech learning suggest that adaptations to foreign language sound categories should happen early in the acquisition process. Results from laboratory language training show effects on non-native perception within one to three weeks of training. Results from linguistic immersion studies...... show differences in adaptations when contrasting averages of 1-2 yrs of experience with 6-7 yrs of experience. We investigated this apparent discrepancy in a longitudinal study on Danish language officer cadets learning either Arabic (MSA and Egyptian dialect) or Dari (Afghan Farsi) through intensive...... (emphatic frication) and a phonemic Dari contrast (fricative voicing) as stimuli for both groups. We saw an effect of learning on the Dari learners’ identification of the Dari stimuli already after three weeks of language training, which was sustained, but not improved, after six and 20 months. The extents...

Longitudinal Space Charge in the SPS

CERN Document Server

Lasheen, Alexandre

2016-01-01

Longitudinal instabilities due to the SPS beam coupling impedance are a major issue for future projects and it is essential to have an accurate SPS impedance model to study them. The longitudinal space charge effect can be modelled by a pure reactive impedance and should also be included in simulations as it may have an impact at low energy. In this Note, the effect of the longitudinal space charge in the SPS is evaluated by taking into account the variation of the transverse beam size and vacuum chamber geometry along the ring. Scaling laws are used to investigate what are the most important parameters for the evaluation of the longitudinal space charge impedance.

Relationships between eating quickly and weight gain in Japanese university students: a longitudinal study.

Science.gov (United States)

Yamane, Mayu; Ekuni, Daisuke; Mizutani, Shinsuke; Kataoka, Kota; Sakumoto-Kataoka, Masami; Kawabata, Yuya; Omori, Chie; Azuma, Tetsuji; Tomofuji, Takaaki; Iwasaki, Yoshiaki; Morita, Manabu

2014-10-01

Many cross-sectional studies have reported a relationship between overweight/obesity and eating quickly, but there have been few longitudinal studies to address this relationship in younger populations. The purpose of this prospective longitudinal study was to investigate whether eating quickly was related to being overweight in Japanese university students. Of 1,396 students who underwent a general examination and completed questionnaires at the start of university and before graduation, 1,314 students (676 male and 638 female) of normal body composition [body mass index (BMI) students whose BMIs were ≥ 25 kg m(-2) were defined as overweight. In this study, 38 participants (2.9%) became overweight. In the logistic regression analysis, the risk of being overweight was increased in males [adjusted odds ratio (OR): 2.77; 95% confidence interval (CI): 1.33-5.79; P university students. Copyright © 2014 The Obesity Society.

Early Acceleration of Mathematics Students and its Effect on Growth in Self-esteem: A Longitudinal Study

Science.gov (United States)

Ma, Xin

2002-11-01

The Longitudinal Study of American Youth (LSAY) database was employed to examine the educational practice of early acceleration of students of mathematics on the development of their self-esteem across the entire secondary grade levels. Students were classified into three different academic categories (gifted, honors, and regular). Results indicated that, in terms of the development of their self-esteem, gifted students benefited from early acceleration, honors students neither benefited nor were harmed by early acceleration, and regular students were harmed by early acceleration. Early acceleration in mathematics promoted significant growth in self-esteem among gifted male students and among gifted, honors, and regular minority students. When students were accelerated, schools showed similar average growth in self-esteem among gifted students and regular students and a large effect of general support for mathematics on the average growth in self-esteem among honors students.

Burnout and Physical Health among Social Workers: A Three-Year Longitudinal Study

Science.gov (United States)

Kim, Hansung; Ji, Juye; Kao, Dennis

2011-01-01

The high risk of burnout in the social work profession is well established, but little is known about burnout's impact on the physical health of social workers. This article examines the relationship between burnout and physical health, using data from a longitudinal study of social workers. California-registered social workers (N = 406) were…

Neural correlates of foreign-language learning in childhood: a 3-year longitudinal ERP study.

Science.gov (United States)

Ojima, Shiro; Nakamura, Naoko; Matsuba-Kurita, Hiroko; Hoshino, Takahiro; Hagiwara, Hiroko

2011-01-01

A foreign language (a language not spoken in one's community) is difficult to master completely. Early introduction of foreign-language (FL) education during childhood is becoming a standard in many countries. However, the neural process of child FL learning still remains largely unknown. We longitudinally followed 322 school-age children with diverse FL proficiency for three consecutive years, and acquired children's ERP responses to FL words that were semantically congruous or incongruous with the preceding picture context. As FL proficiency increased, various ERP components previously reported in mother-tongue (L1) acquisition (such as a broad negativity, an N400, and a late positive component) appeared sequentially, critically in an identical order to L1 acquisition. This finding was supported not only by cross-sectional analyses of children at different proficiency levels but also by longitudinal analyses of the same children over time. Our data are consistent with the hypothesis that FL learning in childhood reproduces identical developmental stages in an identical order to L1 acquisition, suggesting that the nature of the child's brain itself may determine the normal course of FL learning. Future research should test the generalizability of the results in other aspects of language such as syntax.

Childhood Precursors of Adult Borderline Personality Disorder Features: A Longitudinal Study.

Science.gov (United States)

Cramer, Phebe

2016-07-01

This study identifies childhood personality traits that are precursors of adult Borderline Personality Disorder (BPD) features. In a longitudinal study, childhood personality traits were assessed at age 11 (N = 100) using the California Child Q-set (CCQ: Block and Block, 1980). A number of these Q-items were found to be significantly correlated (p personality dimensions: Impulsivity and Nonconformity/Aggression. The findings thus provide evidence that childhood personality traits predict adult BPD features. Identifying such childhood precursors provides an opportunity for early intervention.

A longitudinal study of school belonging and academic motivation across high school.

Science.gov (United States)

Neel, Cari Gillen-O'; Fuligni, Andrew

2013-01-01

This longitudinal study examined how school belonging changes over the years of high school, and how it is associated with academic achievement and motivation. Students from Latin American, Asian, and European backgrounds participated (N = 572; age span = 13.94-19.15 years). In ninth grade, girls' school belonging was higher than boys'. Over the course of high school, however, girls' school belonging declined, whereas boys' remained stable. Within-person longitudinal analyses indicated that years in which students had higher school belonging were also years in which they felt that school was more enjoyable and more useful, above and beyond their actual level of achievement. Results highlight the importance of belonging for maintaining students' academic engagement during the teenage years. © 2012 The Authors. Child Development © 2012 Society for Research in Child Development, Inc.

Development of Working Memory and Performance in Arithmetic: A Longitudinal Study with Children

Science.gov (United States)

López, Magdalena

2014-01-01

Introduction: This study has aimed to investigate the relationship between the development of working memory and performance on arithmetic activities. Method: We conducted a 3-year longitudinal study of a sample of 90 children, that was followed during the first, second and third year of primary school. All children were tested on measures of WM…

Analysis of longitudinal diffusion-weighted images in healthy and pathological aging: An ADNI study.

Science.gov (United States)

Kruggel, Frithjof; Masaki, Fumitaro; Solodkin, Ana

2017-02-15

The widely used framework of voxel-based morphometry for analyzing neuroimages is extended here to model longitudinal imaging data by exchanging the linear model with a linear mixed-effects model. The new approach is employed for analyzing a large longitudinal sample of 756 diffusion-weighted images acquired in 177 subjects of the Alzheimer's Disease Neuroimaging initiative (ADNI). While sample- and group-level results from both approaches are equivalent, the mixed-effect model yields information at the single subject level. Interestingly, the neurobiological relevance of the relevant parameter at the individual level describes specific differences associated with aging. In addition, our approach highlights white matter areas that reliably discriminate between patients with Alzheimer's disease and healthy controls with a predictive power of 0.99 and include the hippocampal alveus, the para-hippocampal white matter, the white matter of the posterior cingulate, and optic tracts. In this context, notably the classifier includes a sub-population of patients with minimal cognitive impairment into the pathological domain. Our classifier offers promising features for an accessible biomarker that predicts the risk of conversion to Alzheimer's disease. Data used in preparation of this article were obtained from the Alzheimer's Disease Neuroimaging Initiative (ADNI) database (adni.loni.usc.edu). As such, the investigators within the ADNI contributed to the design and implementation of ADNI and/or provided data but did not participate in analysis or writing of this report. A complete listing of ADNI investigators can be found at: http://adni.loni.usc.edu/wp-content/uploads/how to apply/ADNI Acknowledgement List.pdf. Significance statement This study assesses neuro-degenerative processes in the brain's white matter as revealed by diffusion-weighted imaging, in order to discriminate healthy from pathological aging in a large sample of elderly subjects. The analysis of time

Reciprocal relations between workplace bullying, anxiety, and vigor: a two-wave longitudinal study.

Science.gov (United States)

Rodríguez-Muñoz, Alfredo; Moreno-Jiménez, Bernardo; Sanz-Vergel, Ana Isabel

2015-01-01

Workplace bullying has been classified as an extreme social stressor in work contexts and has been repeatedly linked to several negative consequences. However, little research has examined reversed or reciprocal relations of bullying and outcomes. We conducted a two-wave longitudinal study with a time lag of six months. The study sample consisted of 348 employees of the Spanish workforce. The present study examined longitudinal relationships between workplace bullying, psychological health, and well-being. On the basis of conservation of resources theory, we hypothesized that we would find reciprocal relations among study variables over time. Results of cross-lagged structural equation modeling analyses supported our hypotheses. Specifically, it was found that Time 1 (T1) workplace bullying was negatively related to Time 2 (T2) vigor and positively related to T2 anxiety. Additionally, T1 anxiety and vigor had an effect on T2 workplace bullying. Overall, these findings support the validity of the theoretical models postulating a reciprocal bullying-outcome relationship, rather than simple one-way causal pathways approaches.

Restoration of longitudinal images.

Science.gov (United States)

Hu, Y; Frieden, B R

1988-01-15

In this paper, a method of restoring longitudinal images is developed. By using the transfer function for longitudinal objects, and inverse filtering, a longitudinal image may be restored. The Fourier theory and sampling theorems for transverse images cannot be used directly in the longitudinal case. A modification and reasonable approximation are introduced. We have numerically established a necessary relationship between just-resolved longitudinal separation (after inverse filtering), noise level, and the taking conditions of object distance and lens diameter. An empirical formula is also found to well-fit the computed results. This formula may be of use for designing optical systems which are to image longitudinal details, such as in robotics or microscopy.

A systematic review of health-related quality of life in longitudinal studies of myeloma patients

DEFF Research Database (Denmark)

Nielsen, Lene Kongsgaard; Jarden, Mary Ellen; Andersen, Christen Lykkegaard

2017-01-01

in HRQoL scores, which is perceived as beneficial to the patient according to two published guidelines. METHODS: A literature search was performed May 2016. Publications with longitudinal follow-up using the EORTC QLQ-C30 instrument for HRQoL measurement of physical functioning, global quality of life......OBJECTIVES: Multiple myeloma (MM) patients report high symptom burden and reduced health-related quality of life (HRQoL) compared to patients with other haematological malignancies. The aim of this review was to analyse published longitudinal studies including MM patients according to a change...... during first-line compared to relapsed treatment regimens. The background of these findings should be in focus in future studies, and HRQoL measurements should be integrated in maintenance studies....

Children's Theory of Mind, Self-Perceptions, and Peer Relations: A Longitudinal Study

Science.gov (United States)

Bosacki, Sandra Leanne

2015-01-01

This longitudinal study explored Theory of Mind (ToM), self-perceptions, and teacher ratings of peer relations of 91 children (52 females, ages 6-8?years) drawn from two schools situated in a mainly Euro-Canadian, middle socioeconomic status, semi-rural central Canadian context. ToM, self-perceptions, and teacher ratings of peer relations were…

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

Science.gov (United States)

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.

Maturational Patterns of Sigma Frequency Power Across Childhood and Adolescence: A Longitudinal Study

Science.gov (United States)

Campbell, Ian G.; Feinberg, Irwin

2016-01-01

Study Objectives: To further evaluate adolescent brain maturation by determining the longitudinal trajectories of nonrapid eye movement (NREM) sigma (11–15 Hz) power across childhood-adolescence. Methods: The maturational trend for sigma (11–15 Hz) power was evaluated in an accelerated longitudinal study of three overlapping age cohorts (n = 92) covering ages 6 to 18 y. Semiannually, sleep electroencephalography (EEG) was recorded from participants sleeping at home in their normal sleep environment while keeping their current school night schedules. Results: Sigma frequencies became faster with age. The frequency of the 11–15 Hz spectral peak increased linearly. Sigma frequency power (SFP) declined with age, but its trajectory was complex (cubic). Power in a group of low sigma subfrequencies declined with age. Power in a group of high sigma frequencies increased with age. Power in subfrequencies within 11–15 Hz also showed different trends across the night, with lower frequencies increasing across NREM periods and higher frequencies decreasing across NREM periods. The upper and lower boundaries for the sigma frequencies that changed across NREMPs shifted upward with age. Conclusions: We hypothesize that these maturational brain changes result from synaptic elimination which decreases sleep depth and streamlines circuits. SFP displays a maturational trajectory different from both delta and theta power. Theories on the function of sigma must be reconciled with its maturational trajectory. These findings further demonstrate the value of sleep EEG for studying noninvasively the complex developmental brain changes of adolescence. Citation: Campbell IG, Feinberg I. Maturational patterns of sigma frequency power across childhood and adolescence: a longitudinal study. SLEEP 2016;39(1):193–201. PMID:26285004

Positive parenting predicts the development of adolescent brain structure: A longitudinal study

Directory of Open Access Journals (Sweden)

Sarah Whittle

2014-04-01

Full Text Available Little work has been conducted that examines the effects of positive environmental experiences on brain development to date. The aim of this study was to prospectively investigate the effects of positive (warm and supportive maternal behavior on structural brain development during adolescence, using longitudinal structural MRI. Participants were 188 (92 female adolescents, who were part of a longitudinal adolescent development study that involved mother–adolescent interactions and MRI scans at approximately 12 years old, and follow-up MRI scans approximately 4 years later. FreeSurfer software was used to estimate the volume of limbic-striatal regions (amygdala, hippocampus, caudate, putamen, pallidum, and nucleus accumbens and the thickness of prefrontal regions (anterior cingulate and orbitofrontal cortices across both time points. Higher frequency of positive maternal behavior during the interactions predicted attenuated volumetric growth in the right amygdala, and accelerated cortical thinning in the right anterior cingulate (males only and left and right orbitofrontal cortices, between baseline and follow up. These results have implications for understanding the biological mediators of risk and protective factors for mental disorders that have onset during adolescence.

A Longitudinal Study of Neurocognition in Dementia with Lewy Bodies Compared to Alzheimer’s Disease

Directory of Open Access Journals (Sweden)

Monica H. Breitve

2018-03-01

Full Text Available IntroductionThere are relatively few longitudinal studies on the differences in cognitive decline between Alzheimer’s disease (AD and dementia with Lewy bodies (DLB, and the majority of existing studies have suboptimal designs.AimWe investigated the differences in cognitive decline in AD compared to DLB over 4 years and cognitive domain predictors of progression.MethodsIn a longitudinal study, 266 patients with first-time diagnosis of mild dementia were included and followed annually. The patients were tested annually with neuropsychological tests and screening instruments [MMSE (Mini-Mental Status Examination, Clinical Dementia Rating (CDR, the second edition of California Verbal Learning Test (CVLT-II, Trail Making Test A & B (TMT A & B, Stroop test, Controlled Oral Word Associations Test (COWAT animal naming, Boston Naming Test, Visual Object and Space Perception Battery (VOSP Cubes and Silhouettes]. Longitudinal analyses were performed with linear mixed effects (LME models and Cox regression. Both specific neuropsychological tests and cognitive domains were analyzed.ResultsThis study sample comprised 119 AD and 67 DLB patients. In TMT A, the DLB patients had a faster decline over 4 years than patients with AD (p = 0.013. No other longitudinal differences in specific neuropsychological tests were found. Higher executive domain scores at baseline were associated with a longer time to reach severe dementia (CDR = 3 or death for the total sample (p = 0.032. High or low visuospatial function at baseline was not found to be associated with cognitive decline (MMSE or progression of dementia severity (CDR over time.ConclusionOver 4 years, patients with DLB had a faster decline in TMT A than patients with AD, but this should be interpreted cautiously. Beyond this, there was little support for faster decline in DLB patients neuropsychologically than in AD patients.

Age, intelligence, and event-related brain potentials during late childhood: A longitudinal study.

NARCIS (Netherlands)

Molenaar, P.C.M.; Molen, M.W.; Stauder, J.E.A.

2003-01-01

he relation between event-related brain activity, age, and intelligence was studied using a visual oddball task presented longitudinally to girls at 9, 10, and 11 years of age. The event-related brain potential (ERP) components showed typical gradual decrements in latency and amplitude with

Online Communication, Compulsive Internet Use, and Psychosocial Well-Being Among Adolescents: A Longitudinal Study

NARCIS (Netherlands)

Eijnden, R.J.J.M. van den; Meerkerk, G.J.; Vermulst, A.A.; Spijkerman, R.; Engels, R.C.M.E.

2008-01-01

The present study investigated the relationships between adolescents' online communication and compulsive Internet use, depression, and loneliness. The study had a 2-wave longitudinal design with an interval of 6 months. The sample consisted of 663 students, 318 male and 345 female, ages 12 to 15

Relationship between Screen-Time and Motor Proficiency in Children: A Longitudinal Study

Science.gov (United States)

Cadoret, Geneviève; Bigras, Nathalie; Lemay, Lise; Lehrer, Joanne; Lemire, Julie

2018-01-01

The objective of this longitudinal study was to examine the relationship between screen time (ST) and children's motor proficiency. The amount of time 113 children spent watching television, using a computer, and playing video games as reported by parents at ages 4, 5, and 7 was measured and children's motor skills were evaluated at age 7 with the…

Project STARS (Studies on Trajectories of Adolescent Relationships and Sexuality) : A longitudinal, multidomain study on sexual development of Dutch adolescents

NARCIS (Netherlands)

Reitz, Ellen; van de Bongardt, Daphne; Baams, Laura; Doornwaard, Suzan; Dalenberg, Wieke; Dubas, Judith; van Aken, Marcel; Overbeek, Geertjan; ter Bogt, Tom; van der Eijnden, Regina; Vanwesenbeeck, Ine; Kunnen, Saskia; Timmerman, Greetje; van Geert, Paul; Dekovic, Maja

2015-01-01

This study gives an overview of Project STARS (Studies on Trajectories of Adolescent Relationships and Sexuality), a four-wave longitudinal study of 1297 Dutch adolescents. First, the sample, measures and four sub-projects are described. Second, hierarchical regression analyses were conducted to

Contextualising case studies in entrepreneurship: A tandem approach to conducting a longitudinal cross-country case study

DEFF Research Database (Denmark)

Chetty, S. K.; Partanen, J.; Rasmussen, Erik Stavnsager

2014-01-01

Using predictive and effectuation logics as a framework, this research note explains how case study research was conducted to demonstrate rigour and relevance. The study involves a longitudinal cross-country case study on small and medium-sized firm growth and networks undertaken by research teams...... in three countries (Finland, Denmark and New Zealand) involving 33 firms. This research note outlines the implications of this research and provides valuable guidance and reflections upon opportunities for future research regarding the conduct of contextual studies in entrepreneurship without compromising...

A longitudinal study of the grief of mothers and fathers of children with intellectual disability.

Science.gov (United States)

Bruce, E J; Schultz, C L; Smyrnios, K X

1996-03-01

As a follow-up to a single-point-in-time study which suggested support for the proposition that grieving is an ongoing feature of parenting children with intellectual disability, the present investigation reports findings based on annual interviews conducted over a three-year period. Longitudinal outcomes on measures used to define grief largely confirmed the original findings. Of particular interest were (a) indications of the presence of grief over time (b) the finding that the 49 mothers and 49 fathers report similar intensity of continued wishing for what might have been, and (c) the conclusion that the responses of the mothers on the Impact of Event Scale and to current levels of distress when thinking about time of diagnoses are significantly more intense than those of the fathers. Attention is drawn to patterns emerging from gender-related differences. Resulted are discussed within the framework of four mandates for research and practice, with particular reference to psycho-educational support through groupwork.

A Chinese Longitudinal Study on Work/Family Enrichment

Science.gov (United States)

Lu, Luo

2011-01-01

Purpose: The purpose of this paper is to explore reciprocal relationships between work/family resources, work/family enrichment (WFE), and work/family satisfaction in a Chinese society. Design/methodology/approach: A longitudinal design was adopted using a three-wave panel sample. Data were obtained from 310 Taiwanese employees on three occasions,…

Participation in medical decision-making across Europe: An international longitudinal multicenter study.

Science.gov (United States)

Bär Deucher, A; Hengartner, M P; Kawohl, W; Konrad, J; Puschner, B; Clarke, E; Slade, M; Del Vecchio, V; Sampogna, G; Égerházi, A; Süveges, Á; Krogsgaard Bording, M; Munk-Jørgensen, P; Rössler, W

2016-05-01

The purpose of this paper was to examine national differences in the desire to participate in decision-making of people with severe mental illness in six European countries. The data was taken from a European longitudinal observational study (CEDAR; ISRCTN75841675). A sample of 514 patients with severe mental illness from the study centers in Ulm, Germany, London, England, Naples, Italy, Debrecen, Hungary, Aalborg, Denmark and Zurich, Switzerland were assessed as to desire to participate in medical decision-making. Associations between desire for participation in decision-making and center location were analyzed with generalized estimating equations. We found large cross-national differences in patients' desire to participate in decision-making, with the center explaining 47.2% of total variance in the desire for participation (Pparticipation, followed by Aalborg (mean=1.97), where scores were in turn significantly higher than in Debrecen (mean=1.56). The lowest scores were reported in Naples (mean=1.14). Over time, the desire for participation in decision-making increased significantly in Zurich (b=0.23) and decreased in Naples (b=-0.14). In all other centers, values remained stable. This study demonstrates that patients' desire for participation in decision-making varies by location. We suggest that more research attention be focused on identifying specific cultural and social factors in each country to further explain observed differences across Europe. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

College Women's Female Friendships: A Longitudinal View

Science.gov (United States)

Aleman, Ana M. Martinez

2010-01-01

This article presents a longitudinal qualitative study of the cognitive value of female friendships formed in college and seeks to appraise the meaning of the phenomenon for the participants. To grasp the temporal effects of the longitudinal data in this study, the author examines and assesses the relevant developmental literature, particularly…

Sleep was associated with depression and anxiety status during pregnancy: a prospective longitudinal study.

Science.gov (United States)

Yu, Yunxian; Li, Minchao; Pu, Liuyan; Wang, Shuojia; Wu, Jinhua; Ruan, Lingli; Jiang, Shuying; Wang, Zhaopin; Jiang, Wen

2017-10-01

The purpose of this study was to reveal the cross-sectional and longitudinal association of sleep with depression and anxiety among Chinese pregnant women. Pregnant women were recruited in Zhoushan Pregnant Women Cohort at Zhoushan Maternal and Child Care Hospital from 2011 to 2015. Self-rating depression scales (SDS) and self-rating anxiety scales (SAS) were used for evaluating depression and anxiety status at each trimester; corresponding sleep quality and duration were reported by pregnant women. Ordinary or multilevel linear and logistic regression model were used to estimate the cross-sectional or longitudinal association of sleep with depression and anxiety. The prevalence rates were 35.64, 24.23, and 26.24% for depression and 22.57, 17.41, and 21.04% for anxiety at 1st (T1), 2nd (T2), and 3rd trimester (T3), respectively. Controlling for potential confounders, it revealed significant cross-sectional and longitudinal associations of sleep with depression and anxiety status. In cross-sectional analysis, women who slept less than 8 h/day had higher risk of depression (T1: OR (95%CI) = 1.75 (1.39, 2.20); T2: 1.52 (1.26, 2.05); T3: 1.60 (1.18, 2.05)) and anxiety (T1: 2.00 (1.57, 2.55); T2: 1.86 (1.37, 2.54); T3: 1.33 (0.99, 1.79)). In the longitudinal analysis, multilevel model revealed that women with subjective "fair" or "bad" sleep quality had elevated risk of depression (OR ranging from 1.54 to 3.71) and anxiety (2.38 to 7.53) during pregnancy. Prenatal depression and anxiety status were prevalent in pregnant women. Sleep quality was associated with depression and anxiety status in both cross-sectional and longitudinal analyses, implying that improving sleep quality should benefit for mental health of pregnant women.

Consideration on longitudinal bending moment in waves of a large high-speed ship; Ogata kosokutei no haro tatemage moment ni kansuru ichikosatsu

Energy Technology Data Exchange (ETDEWEB)

Deguchi, M; Takimoto, T; Kasuda, T; Tozawa, S [Mitsubishi Heavy Industries, Ltd., Tokyo (Japan)

1996-04-10

While high-speed ships are on a trend of increased speed, size and diversity, one of the most important items is a discussion on large high-speed ships with a total length of 100 m class on their longitudinal strength in waves. With such a background, a model ship intended of realizing a large high-speed was assumed, and verification of reliability in structural strength and establishment of a design method for this ship were intended. Therefore, oceanographic condition setting, design load setting, FEM analysis, and strength assessment were carried out. This paper reports the results of comparison with and consideration on conventional criteria and linear calculations, mainly the results of simulated calculations on non-linear hull movement/wave load which have been performed in discussing the loads. The result of the non-linear simulation is thought to have well simulated non-linearity characteristic to the ship. Conventional criteria which have been arranged on the record of use for small ships are considered impossible to be applied to large high-speed ships. Under such a situation, the simplified equations by Kaneko et al are judged effective in making an initial plan for this type of ship. 6 refs., 7 figs., 2 tabs.

Intrinsic and Extrinsic Reading Motivation as Predictors of Reading Literacy: A Longitudinal Study

Science.gov (United States)

Becker, Michael; McElvany, Nele; Kortenbruck, Marthe

2010-01-01

The purpose in this study was to examine the longitudinal relationships of intrinsic and extrinsic motivation with reading literacy development. In particular, the authors (a) investigated reading amount as mediator between motivation and reading literacy and (b) probed for bidirectional relationships between reading motivation and reading…

Effects of attitude dissimilarity and time on social integration : A longitudinal panel study

NARCIS (Netherlands)

Van der Vegt, G.S.

2002-01-01

A longitudinal panel study in 25 work groups of elementary school teachers examined the effect of attitudinal dissimilarity and time on social integration across a 9-month period. In line with the prediction based on both the similarity-attraction approach and social identity theory, cross-lagged

Large Scale Survey Data in Career Development Research

Science.gov (United States)

Diemer, Matthew A.

2008-01-01

Large scale survey datasets have been underutilized but offer numerous advantages for career development scholars, as they contain numerous career development constructs with large and diverse samples that are followed longitudinally. Constructs such as work salience, vocational expectations, educational expectations, work satisfaction, and…

Estimates of post-acceleration longitudinal bunch compression

International Nuclear Information System (INIS)

Judd, D.L.

1977-01-01

A simple analytic method is developed, based on physical approximations, for treating transient implosive longitudinal compression of bunches of heavy ions in an accelerator system for ignition of inertial-confinement fusion pellet targets. Parametric dependences of attainable compressions and of beam path lengths and times during compression are indicated for ramped pulsed-gap lines, rf systems in storage and accumulator rings, and composite systems, including sections of free drift. It appears that for high-confidence pellets in a plant producing 1000 MW of electric power the needed pulse lengths cannot be obtained with rings alone unless an unreasonably large number of them are used, independent of choice of rf harmonic number. In contrast, pulsed-gap lines alone can meet this need. The effects of an initial inward compressive drift and of longitudinal emittance are included

Dietary patterns in the Avon Longitudinal Study of Parents and Children

Science.gov (United States)

Jones, Louise R.; Northstone, Kate

2015-01-01

Publications from the Avon Longitudinal Study of Parents and Children that used empirically derived dietary patterns were reviewed. The relationships of dietary patterns with socioeconomic background and childhood development were examined. Diet was assessed using food frequency questionnaires and food records. Three statistical methods were used: principal components analysis, cluster analysis, and reduced rank regression. Throughout childhood, children and parents have similar dietary patterns. The “health-conscious” and “traditional” patterns were associated with high intakes of fruits and/or vegetables and better nutrient profiles than the “processed” patterns. There was evidence of tracking in childhood diet, with the “health-conscious” patterns tracking most strongly, followed by the “processed” pattern. An “energy-dense, low-fiber, high-fat” dietary pattern was extracted using reduced rank regression; high scores on this pattern were associated with increasing adiposity. Maternal education was a strong determinant of pattern score or cluster membership; low educational attainment was associated with higher scores on processed, energy-dense patterns in both parents and children. The Avon Longitudinal Study of Parents and Children has provided unique insights into the value of empirically derived dietary patterns and has demonstrated that they are a useful tool in nutritional epidemiology. PMID:26395343

Physical activity as a determinant of change in mobility performance : the Longitudinal Aging Study Amsterdam

NARCIS (Netherlands)

Visser, Marjolein; Pluijm, Saskia M F; Stel, Vianda S; Bosscher, Ruud J; Deeg, Dorly J H

2002-01-01

OBJECTIVES: This study examined the association of (change in) physical activity and decline in mobility performance in older men and women. DESIGN: A 3-year prospective study using data of the Longitudinal Aging Study. SETTING: Netherlands. PARTICIPANTS: Two thousand one hundred nine men and women

Recommendations to improve imaging and analysis of brain lesion load and atrophy in longitudinal studies of multiple sclerosis

DEFF Research Database (Denmark)

Vrenken, H; Jenkinson, M; Horsfield, M A

2013-01-01

resonance image analysis methods for assessing brain lesion load and atrophy, this paper makes recommendations to improve these measures for longitudinal studies of MS. Briefly, they are (1) images should be acquired using 3D pulse sequences, with near-isotropic spatial resolution and multiple image......Focal lesions and brain atrophy are the most extensively studied aspects of multiple sclerosis (MS), but the image acquisition and analysis techniques used can be further improved, especially those for studying within-patient changes of lesion load and atrophy longitudinally. Improved accuracy...

Reading in dyslexia across literacy development: A longitudinal study of effective connectivity.

Science.gov (United States)

Morken, Frøydis; Helland, Turid; Hugdahl, Kenneth; Specht, Karsten

2017-01-01

Dyslexia is a literacy disorder affecting the efficient acquisition of reading and writing skills. The disorder is neurobiological in origin. Due to its developmental nature, longitudinal studies of dyslexia are of essence. They are, however, relatively scarce. The present study took a longitudinal approach to cortical connectivity of brain imaging data in reading tasks in children with dyslexia and children with typical reading development. The participants were followed with repeated measurements through Pre-literacy (6 years old), Emergent Literacy (8 years old) and Literacy (12 years old) stages, using Dynamic Causal Modelling (DCM) when analysing functional magnetic resonance imaging (fMRI) data. Even though there are a few longitudinal studies on effective connectivity in typical reading, to our knowledge, no studies have previously investigated these issues in relation to dyslexia. We set up a model of a brain reading network involving five cortical regions (inferior frontal gyrus, precentral gyrus, superior temporal gyrus, inferior parietal lobule, and occipito-temporal cortex). Using DCM, connectivity measures were calculated for each connection in the model. These measures were further analysed using factorial ANOVA. The results showed that the difference between groups centred on connections going to and from the inferior frontal gyrus (two connections) and the occipito-temporal cortex (three connections). For all five connections, the typical group showed stable or decreasing connectivity measures. The dyslexia group, on the other hand, showed a marked up-regulation (occipito-temporal connections) or down-regulation (inferior frontal gyrus connections) from 6 years to 8 years, followed by normalization from 8 years to 12 years. We interpret this as a delay in the dyslexia group in developing into the Pre-literacy and Emergent literacy stages. This delay could possibly be detrimental to literacy development. By age 12, there was no statistically

Association between bacterial vaginosis and partner concurrency: a longitudinal study.

Science.gov (United States)

Kenyon, Chris R; Buyze, Jozefien; Klebanoff, Mark; Brotman, Rebecca M

2018-02-01

The study aimed to test if there was an association between prevalent bacterial vaginosis (BV) and women reporting that their partner had other partners at the same time (partner concurrency). This association has not been assessed in a longitudinal cohort. The Longitudinal Study of Vaginal Flora recruited a cohort of 3620 non-pregnant women aged 15-44 years who presented for routine primary healthcare at 12 clinics in Birmingham, Alabama. Behavioural questionnaires and vaginal smears were obtained quarterly for a year and BV was defined by a Nugent score 7 or higher as well as Amsel criteria. Mixed effects logistic regression was used to assess the relationship between prevalent BV and reporting that one's partner had other partners in the preceding 3-6 months time interval. Nugent score prevalent BV was associated with both reporting that one's partner definitely (adjusted OR (aOR) 1.5; 95% CI 1.2 to 1.8) and possibly (aOR 1.5; 95% CI 1.2 to 1.8) engaged in partner concurrency in the preceding 3-6 months time period. Prevalent BV diagnosed by Amsel criteria was similar. A diagnosis of prevalent BV was associated with reporting that one's partner possibly or definitely engaged in partner concurrency. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

The Relationship Between Shift Work and Metabolic Risk Factors: A Systematic Review of Longitudinal Studies.

Science.gov (United States)

Proper, Karin I; van de Langenberg, Daniëlla; Rodenburg, Wendy; Vermeulen, Roel C H; van der Beek, Allard J; van Steeg, Harry; van Kerkhof, Linda W M

2016-05-01

Although the metabolic health effects of shift work have been extensively studied, a systematic synthesis of the available research is lacking. This review aimed to systematically summarize the available evidence of longitudinal studies linking shift work with metabolic risk factors. A systematic literature search was performed in 2015. Studies were included if (1) they had a longitudinal design; (2) shift work was studied as the exposure; and (3) the outcome involved a metabolic risk factor, including anthropometric, blood glucose, blood lipid, or blood pressure measures. Eligible studies were assessed for their methodologic quality in 2015. A best-evidence synthesis was used to draw conclusions per outcome. Thirty-nine articles describing 22 studies were included. Strong evidence was found for a relation between shift work and increased body weight/BMI, risk for overweight, and impaired glucose tolerance. For the remaining outcomes, there was insufficient evidence. Shift work seems to be associated with body weight gain, risk for overweight, and impaired glucose tolerance. Overall, lack of high-methodologic quality studies and inconsistency in findings led to insufficient evidence in assessing the relation between shift work and other metabolic risk factors. To strengthen the evidence, more high-quality longitudinal studies that provide more information on the shift work schedule (e.g., frequency of night shifts, duration in years) are needed. Further, research to the (mediating) role of lifestyle behaviors in the health effects of shift work is recommended, as this may offer potential for preventive strategies. Copyright © 2016. Published by Elsevier Inc.

Longitudinal beam dynamics at transition crossing

Energy Technology Data Exchange (ETDEWEB)

Bogacz, S.A.

1991-11-01

A brief outline of the longitudinal single particle dynamics at transition is presented in terms of phase-space mappings. Simple quantitative prediction about the phase-space dilution is made. More realistic simulation (ESME) of the transition crossing is carried out (including various collective and single particle effects contributing to the longitudinal emittance blow up). The simulation takes into account the longitudinal space-charge force (bunch length oscillation), the transverse space-charge (the Umstaetter effect) and finally the dispersion of the momentum compaction factor (the Johnsen effect). As a result of this simulation one can separate relative strengths of the above mechanisms and study their individual effects on the longitudinal phase-space evolution, especially filamentation of the bunch and formation of a galaxy-like'' pattern. 7 refs., 2 figs.

Digital Entrepreneurship in a Traditional Production Firm: A Longitudinal Case Study

OpenAIRE

Martin Hannibal; Erik S. Rasmussen

2014-01-01

Through a longitudinal case study this paper explores the repercussions from introducing a mobile commerce platform as just another instrument in the marketing toolbox in a traditional sales-oriented firm. Findings suggest that the implementation of the M-platform in addition to its intended purpose spawns a digital business model that allows the company to change its relations to distributors, retailers and customers enabling access to direct communication with end-users. However, the emergi...

A Longitudinal Study of Laterality Expression and Teacher Evaluation of Elementary School Children

Science.gov (United States)

Van Camp, Sarah S.

1978-01-01

A three-year longitudinal study conducted to assess the incidence of mixed laterality in elementary school children showed that thirty-seven percent of the eighty-two subjects had mixed laterality. No relationship was found between perceptual motor and academic achievement as measured by teacher ratings and mixed laterality. (MF)

"A Writer More than . . . A Child": A Longitudinal Study Examining Adolescent Writer Identity

Science.gov (United States)

Lammers, Jayne C.; Marsh, Valerie L.

2018-01-01

This article reconsiders theoretical claims of identity fluidity, stability, and agency through a longitudinal case study investigating one adolescent's writing over time and across spaces. Qualitative data spanning her four years of high school were collected and analyzed using a grounded theory approach with literacy-and-identity theory…

Relationships between Substance Use and Depressive Symptoms: A Longitudinal Study of Australian Adolescents

Science.gov (United States)

Scholes-Balog, Kirsty E.; Hemphill, Sheryl A.; Patton, George C.; Toumbourou, John W.

2015-01-01

This study examined longitudinal relationships between depressive symptoms and use of alcohol, cigarettes, and illicit substances among adolescents, addressing methodological limitations and potential confounding in the extant literature. The sample comprised adolescents who were surveyed in Grades 6 (n = 916), 9 (n = 804), and 11 (n = 791).…

A longitudinal study of paternal mental health during transition to fatherhood as young adults.

Science.gov (United States)

Garfield, Craig F; Duncan, Greg; Rutsohn, Joshua; McDade, Thomas W; Adam, Emma K; Coley, Rebekah Levine; Chase-Lansdale, P Lindsay

2014-05-01

Rates of paternal depression range from 5% to 10% with a growing body of literature describing the harm to fathers, children, and families. Changes in depression symptoms over the life course, and the role of social factors, are not well known. This study examines associations with changes in depression symptoms during the transition to fatherhood for young fathers and whether this association differed by key social factors. We combined all 4 waves of the National Longitudinal Study of Adolescent Health to support a 23-year longitudinal analysis of 10 623 men and then created a "fatherhood-year" data set, regressing age-adjusted standardized depressive symptoms scores on fatherhood status (nonresidence/residence), fatherhood-years, and covariates to determine associations between Center for Epidemiologic Studies Depression Scale scores and fatherhood life course intervals. Depressive symptom scores reported at the entry into fatherhood are higher for nonresident fathers than nonfathers, which in turn are higher than those of resident fathers. Resident fathers have a significant decrease in scores during late adolescence (β = -0.035, P = .023), but a significant increase in scores during early fatherhood (β = 0.023, P = .041). From entrance into fatherhood to the end of early fatherhood (+5 years), the depressive symptoms score for resident fathers increases on average by 68%. In our longitudinal, population-based study, resident fathers show increasing depressive symptom scores during children's key attachment years of 0-5. Identifying at-risk fathers based on social factors and designing effective interventions may ultimately improve health outcomes for the entire family. Copyright © 2014 by the American Academy of Pediatrics.

The Relationship Between Shift Work and Metabolic Risk Factors : A Systematic Review of Longitudinal Studies

NARCIS (Netherlands)

Proper, Karin I; van de Langenberg, Daniëlla|info:eu-repo/dai/nl/374886970; Rodenburg, Wendy; Vermeulen, Roel C H|info:eu-repo/dai/nl/216532620; van der Beek, Allard J; van Steeg, Harry; van Kerkhof, Linda W M

2016-01-01

CONTEXT: Although the metabolic health effects of shift work have been extensively studied, a systematic synthesis of the available research is lacking. This review aimed to systematically summarize the available evidence of longitudinal studies linking shift work with metabolic risk factors.

PROBLEMAS DE TRADUCCIÓN, DETECCIÓN Y DESCRIPCIÓN: UN ESTUDIO LONGITUDINAL EN LA FORMACIÓN DE TRADUCTORES / IDENTIFYING AND DESCRIBING TRANSLATION PROBLEMS: A LONGITUDINAL CASE-STUDY IN TRANSLATOR TRAINING

Directory of Open Access Journals (Sweden)

Ana Gregorio Cano

2017-12-01

Full Text Available RESUMEN: Esta investigación se enmarca dentro del área de la traducción e interpretación y, más específicamente, en el campo de la didáctica de la traducción. El objetivo general de la investigación de este estudio fue observar y analizar el impacto de la formación recibida en el seno de los estudios de Traducción en cinco universidades diferentes en España. Con el fin de alcanzar el objetivo de investigación se combinan los enfoques cuantitativos y cualitativos a través del diseño de un macro-estudio con más de 1.000 participantes y un estudio longitudinal de 37 estudiantes. Nuestra investigación se enfoca específicamente en el desarrollo de la competencia estratégica (CE y, particularmente, la capacidad del estudiante para identificar y describir problemas de traducción. Además, en el caso del estudio longitudinal se formularon cuatro hipótesis para ser comprobadas o refutadas a partir de las respuestas de los estudiantes. En este artículo presentamos los resultados correspondientes a la hipótesis número 4, a saber: la riqueza del metalenguaje utilizado por los estudiantes de TI evoluciona desde el principio hasta el final de su carrera. Los resultados del estudio longitudinal no demuestran patrones en el desarrollo de la CE, aunque el metalenguaje utilizado por los estudiantes experimenta cierta evolución. ABSTRACT: This research is framed within the area of translation and interpreting studies and more specifically within the field of translation didactics. The general research objective of this study is to observe and analyze the repercussions of Translation undergraduate courses at five different universities in Spain. With empirical methods combining quantitative and qualitative analysis relying on a macro-study of more than 1,000 subjects and a longitudinal study of 37 students, the research focuses specifically on the development of the strategic competence (SC and, particularly, the student’s capacity to

Cross-Sectional Analysis of Longitudinal Mediation Processes.

Science.gov (United States)

O'Laughlin, Kristine D; Martin, Monica J; Ferrer, Emilio

2018-01-01

Statistical mediation analysis can help to identify and explain the mechanisms behind psychological processes. Examining a set of variables for mediation effects is a ubiquitous process in the social sciences literature; however, despite evidence suggesting that cross-sectional data can misrepresent the mediation of longitudinal processes, cross-sectional analyses continue to be used in this manner. Alternative longitudinal mediation models, including those rooted in a structural equation modeling framework (cross-lagged panel, latent growth curve, and latent difference score models) are currently available and may provide a better representation of mediation processes for longitudinal data. The purpose of this paper is twofold: first, we provide a comparison of cross-sectional and longitudinal mediation models; second, we advocate using models to evaluate mediation effects that capture the temporal sequence of the process under study. Two separate empirical examples are presented to illustrate differences in the conclusions drawn from cross-sectional and longitudinal mediation analyses. Findings from these examples yielded substantial differences in interpretations between the cross-sectional and longitudinal mediation models considered here. Based on these observations, researchers should use caution when attempting to use cross-sectional data in place of longitudinal data for mediation analyses.

Development of numerical processing in children with typical and dyscalculic arithmetic skills—a longitudinal study

Science.gov (United States)

Landerl, Karin

2013-01-01

Numerical processing has been demonstrated to be closely associated with arithmetic skills, however, our knowledge on the development of the relevant cognitive mechanisms is limited. The present longitudinal study investigated the developmental trajectories of numerical processing in 42 children with age-adequate arithmetic development and 41 children with dyscalculia over a 2-year period from beginning of Grade 2, when children were 7; 6 years old, to beginning of Grade 4. A battery of numerical processing tasks (dot enumeration, non-symbolic and symbolic comparison of one- and two-digit numbers, physical comparison, number line estimation) was given five times during the study (beginning and middle of each school year). Efficiency of numerical processing was a very good indicator of development in numerical processing while within-task effects remained largely constant and showed low long-term stability before middle of Grade 3. Children with dyscalculia showed less efficient numerical processing reflected in specifically prolonged response times. Importantly, they showed consistently larger slopes for dot enumeration in the subitizing range, an untypically large compatibility effect when processing two-digit numbers, and they were consistently less accurate in placing numbers on a number line. Thus, we were able to identify parameters that can be used in future research to characterize numerical processing in typical and dyscalculic development. These parameters can also be helpful for identification of children who struggle in their numerical development. PMID:23898310

The longitudinal joint effect of obesity and major depression on work performance impairment.

Science.gov (United States)

Nigatu, Yeshambel T; Reijneveld, Sijmen A; Penninx, Brenda W J H; Schoevers, Robert A; Bültmann, Ute

2015-05-01

We examined the longitudinal effect of obesity, major depression, and their combination on work performance impairment (WPI). We collected longitudinal data (2004-2013) on 1726 paid employees from the Netherlands Study of Depression and Anxiety at baseline and 2-, 4-, and 6-year follow-up. We defined obesity with body mass index and waist circumference. We diagnosed major depression with the Composite International Diagnostic Interview 2.1. We assessed work performance impairment with a questionnaire for illness-associated costs. We used generalized estimating equations for modeling, and estimated interaction on the additive scale. Obesity, abdominal obesity, and major depression were longitudinally associated with increased risk of high WPI. The combinations of obesity and major depression, and of abdominal obesity and major depression were associated with increased risk of high WPI (odds ratios of 2.36 [95% confidence interval = 1.61, 3.44] and 1.88 [95% confidence interval = 1.40, 2.53], respectively), but the relative excess risks attributable to interaction were nonsignificant. The longitudinal joint effect of obesity and major depression on high WPI implies that obesity intervention may be more beneficial for individuals with major depression than those without regarding risk of high WPI, if confirmed in a large, representative sample.

A Longitudinal Study of the Role of T Cell subset, Th1/Th2 cytokines ...

African Journals Online (AJOL)

A Longitudinal Study of the Role of T Cell subset, Th1/Th2 cytokines and antiplasmodial antibodies in uncomplicated Malaria in a Village Population Chronically Exposed to Plasmodium falciparum Malaria.

The ROOTS study: a 10-year review of findings on adolescent depression, and recommendations for future longitudinal research.

Science.gov (United States)

Lewis, Gemma; Jones, Peter B; Goodyer, Ian M

2016-02-01

The purpose of this study is to review longitudinal findings on adolescent mental health from the 'ROOTS study', and provide directions and recommendations for future longitudinal research. To do this, we discuss relevant findings from the ROOTS study, and review its strengths and limitations. We examined all publications from the ROOTS study up to July 2015, selected those examining adolescent mental health, and classified them as investigating (a) childhood risk factors for adolescent depression, (b) genetic and cognitive vulnerability to depression in adolescence, (c) genetic markers, childhood adversities, and neuroendophenotypes, (d) morning cortisol and depression, (e) physical activity and depression symptoms, and (f) the underlying structure of mental health in adolescence. We reviewed the strengths and limitations of the ROOTS study, and how they feed into recommendations for future longitudinal research. There was evidence supporting a putative hormonal biomarker for the emergence of depression in boys. Environmental pathways from child adversity to adolescent depression were confirmed in girls, partly accounted for by negative life events in early adolescence. The preceding role of automatic cognitive biases assessed using behavioural tasks was substantiated, with evidence for genetic susceptibility. Novel latent statistical models of child adversity, depression, anxiety, and psychotic experiences were produced, with concurrent and prospective validity. Our experiences conducting the ROOTS study resulted in a set of strengths, limitations, and recommendations for future longitudinal studies. The ROOTS study has advanced knowledge on the aetiology of adolescent depression by investigating environmental, genetic, hormonal, and neural risk factors. Findings provide a foundation for future research integrating cognitive neuroscience with epidemiology.

A longitudinal study of the effects of television viewing on aggressive and prosocial behaviours

NARCIS (Netherlands)

Wiegman, O.; Kuttschreuter, M.; Baarda, B.

1992-01-01

A longitudinal study investigated the extent to which children's exposure to aggressive and prosocial television models in drama programmes influences their aggressive and prosocial behaviour. In The Netherlands we did not find significant positive correlations between prosocial behaviour and the

A Longitudinal Study on Mathematics Teaching Efficacy: Which Factors (Un)Support the Development?

Science.gov (United States)

Isiksal-Bostan, Mine

2016-01-01

The aim of this longitudinal study was to examine prospective teachers' mathematics teaching efficacy belief during their enrollment in teacher education program and at the end of their first year of teaching. In addition, the factors that enhance or inhibit participants' efficacy belief and how these factors affect their mathematics teaching…

Understanding Student Stress and Coping in Elementary School: A Mixed-Method, Longitudinal Study

Science.gov (United States)

Sotardi, Valerie A.

2016-01-01

This mixed-method, longitudinal study examined daily school stress and coping strategies of elementary schoolchildren in the United States. Students (n = 65) between the ages of 7 and 11 years reported daily school stress measures for 8 weeks and completed individual stress and coping interviews. Results highlight critical relations between…

Basic Aspects of Infant-Grandparent "Interaction": An Eight-Month Longitudinal and Naturalistic Study

Science.gov (United States)

Pratikaki, Anastasia; Germanakis, Ioannis; Kokkinaki, Theano

2011-01-01

This longitudinal and naturalistic study aims to describe basic aspects of early imitative exchanges in dyadic infant-grandfather and infant-grandmother free interactions, from the second to the 10th month of age. Sixteen infants were video-recorded at home in the course of spontaneous dyadic interactions with maternal grandfathers and…

A Longitudinal Study of Pragmatic Language Development in Three Children with Cochlear Implants

Science.gov (United States)

Dammeyer, Jesper

2012-01-01

Research has shown how cochlear implants (CIs), in children with hearing impairments, have improved speech perception and production, but very little is known about the children's pragmatic language development. During a 4-year longitudinal study of three children with CIs, certain aspects of pragmatic language development were observed in free…

Locus of control and frequency of physician visits: Results of a population-based longitudinal study in Germany.

Science.gov (United States)

Hajek, André; König, Hans-Helmut

2017-09-01

To examine the role of internal and external locus of control (LOC) in the frequency of physician visits longitudinally. A nationally representative, longitudinal cohort study of German households. Data were used from the years 2005 and 2010. Data were gathered from the German Socio-Economic Panel (GSOEP). The ten internal and external LOC items in the SOEP are based on a scale by Krampen. The number of physician visits in the last 3 months was used as outcome variable. According to Andersen's behavioural model, predisposing characteristics, enabling resources, and need factors were included as control variables. Fixed-effects Poisson regressions showed that physician visits increased with increasing external LOC, whereas changes in internal LOC were not associated with changes in physician visits. Furthermore, physician visits increased with need factors (decreased self-rated health; onset of disability), whereas predisposing characteristics and the enabling resources were not associated with physician visits. Our findings emphasize the meaning of changes in external LOC for physician visits. As there is evidence that interventions can change the LOC, efforts to modify external LOC might be beneficial for the health care system. Statement of contribution What is already known on this subject? A few cross-sectional studies have investigated the association between locus of control (LOC) and health care use. Longitudinal studies are needed to get a deeper understanding of the causal relationship between these factors. What does this study add? Our longitudinal study provides insights into the impact of general internal and external LOC on physician visits. This is the first study examining the long-term relation in Germany using a population-based sample. © 2017 The British Psychological Society.

Longitudinal motor development of "apparently normal" high-risk infants at 18 months, 3 and 5 years.

Science.gov (United States)

Goyen, Traci Anne; Lui, Kei

2002-12-01

Motor development appears to be more affected by premature birth than other developmental domains, however few studies have specifically investigated the development of gross and fine motor skills in this population. To examine longitudinal motor development in a group of "apparently normal" high-risk infants. Developmental follow-up clinic in a perinatal centre. Longitudinal observational cohort study. Fifty-eight infants born less than 29 weeks gestation and/or 1000 g and without disabilities detected at 12 months. Longitudinal gross and fine motor skills at 18 months, 3 and 5 years using the Peabody Developmental Motor Scales. The HOME scale provided information of the home environment as a stimulus for development. A large proportion (54% at 18 months, 47% at 3 years and 64% at 5 years) of children continued to have fine motor deficits from 18 months to 5 years. The proportion of infants with gross motor deficits significantly increased over this period (14%, 33% and 81%, pmotor development was positively influenced by the quality of the home environment. A large proportion of high-risk infants continued to have fine motor deficits, reflecting an underlying problem with fine motor skills. The proportion of infants with gross motor deficits significantly increased, as test demands became more challenging. In addition, the development of gross and fine motor skills appears to be influenced differently by the home environment.

Triglyceride and glucose (TyG) index as a predictor of incident hypertension: a 9-year longitudinal population-based study

OpenAIRE

Zheng, Rongjiong; Mao, Yushan

2017-01-01

Background Hypertension and the triglyceride and glucose index both have been associated with insulin resistance; however, the longitudinal association remains unclear. This study was designed to investigate the longitudinal association between the triglyceride and glucose index and incident hypertension among the Chinese population. Methods We studied 4686 subjects (3177 males and 1509 females) and followed up for 9?years. The subjects were divided into four groups based on the triglyceride ...

Generation of longitudinally polarized terahertz pulses with field amplitudes exceeding 2 kV/cm

Science.gov (United States)

Cliffe, M. J.; Rodak, A.; Graham, D. M.; Jamison, S. P.

2014-11-01

We demonstrate the generation of near-single cycle longitudinally polarized terahertz radiation using a large-area radially biased photoconductive antenna with a longitudinal field amplitude in excess of 2 kV/cm. The 76 mm diameter antenna was photo-excited by a 0.5 mJ amplified near-infrared femtosecond laser system and biased with a voltage of up to 100 kV applied over concentric electrodes. Amplitudes for both the transverse and longitudinal field components of the source were measured using a calibrated electro-optic detection scheme. By tightly focusing the radiation emitted from the photoconductive antenna, we obtained a maximum longitudinal field amplitude of 2.22 kV/cm with an applied bias field of 38.5 kV/cm.

Longitudinal and transverse right ventricular function in pulmonary hypertension: cardiovascular magnetic resonance imaging study from the ASPIRE registry.

Science.gov (United States)

Swift, Andrew J; Rajaram, Smitha; Capener, Dave; Elliot, Charlie; Condliffe, Robin; Wild, Jim M; Kiely, David G

2015-09-01

Right ventricular (RV) function is a strong predictor of outcome in cardiovascular diseases. Two components of RV function, longitudinal and transverse motion, have been investigated in pulmonary hypertension (PH). However, their individual clinical significance remains uncertain. The aim of this study was to determine the factors associated with transverse and longitudinal RV motion in patients with PH. In 149 treatment-naive patients with PH and 16 patients with suspected PH found to have mean pulmonary arterial pressure of transverse motion (fractional septum to free wall distance [f-SFD]; P = 0.002). In patients without PH, no significant difference between f-SFD and f-TAAD was identified (P = 0.442). Longitudinal RV motion was singularly associated with RV ejection fraction independent of age, invasive hemodynamics, and cardiac magnetic resonance measurements (P = 0.024). In contrast, transverse RV motion was independently associated with left ventricular eccentricity (P = 0.036) in addition to RV ejection fraction (P = 0.014). In conclusion, RV motion is significantly greater in the longitudinal direction in patients with PH, whereas patients without PH have equal contributions of transverse and longitudinal motion. Longitudinal RV motion is primarily associated with global RV pump function in PH. Transverse RV motion not only reflects global pump function but is independently influenced by ventricular interaction in patients with PH.

Positive parenting predicts the development of adolescent brain structure: a longitudinal study.

Science.gov (United States)

Whittle, Sarah; Simmons, Julian G; Dennison, Meg; Vijayakumar, Nandita; Schwartz, Orli; Yap, Marie B H; Sheeber, Lisa; Allen, Nicholas B

2014-04-01

Little work has been conducted that examines the effects of positive environmental experiences on brain development to date. The aim of this study was to prospectively investigate the effects of positive (warm and supportive) maternal behavior on structural brain development during adolescence, using longitudinal structural MRI. Participants were 188 (92 female) adolescents, who were part of a longitudinal adolescent development study that involved mother-adolescent interactions and MRI scans at approximately 12 years old, and follow-up MRI scans approximately 4 years later. FreeSurfer software was used to estimate the volume of limbic-striatal regions (amygdala, hippocampus, caudate, putamen, pallidum, and nucleus accumbens) and the thickness of prefrontal regions (anterior cingulate and orbitofrontal cortices) across both time points. Higher frequency of positive maternal behavior during the interactions predicted attenuated volumetric growth in the right amygdala, and accelerated cortical thinning in the right anterior cingulate (males only) and left and right orbitofrontal cortices, between baseline and follow up. These results have implications for understanding the biological mediators of risk and protective factors for mental disorders that have onset during adolescence. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

Cultural events – does attendance improve health? Evidence from a Polish longitudinal study

Directory of Open Access Journals (Sweden)

Dorota Węziak-Białowolska

2016-08-01

Full Text Available Abstract Background Although there is strong advocacy for uptake of both the arts and creative activities as determinants of individual health conditions, studies evaluating causal influence of attendance at cultural events on population health using individual population data on health are scarce. If available, results are often only of an associative nature. In this light, this study investigated causative impact of attendance at cultural events on self-reported and physical health in the Polish population. Methods Four recent waves (2009, 2011, 2013 and 2015 of the biennial longitudinal Polish household panel study, Social Diagnosis, were analysed. The data, representative for the Polish population aged over 16, with respect to age, gender, classes of place of residence and NUTS 2 regions, were collected from self-report questionnaires. Causative influence of cultural attendance on population health was established using longitudinal population representative data. To account for unobserved heterogeneity of individuals and to mitigate issues caused by omitted variables, a panel data model with a fixed effects estimator was applied. The endogeneity problem (those who enjoy good health are more likely to participate in cultural activities more frequently was circumvented by application of instrumental variables. Results Results confirmed positive association between cultural attendance and self-reported health. However, in contrast to the often suggested positive causative relationship, such a link was not confirmed by the study. Additionally, no evidence was found to corroborate a positive impact from cultural attendance on physical health. Both findings were substantiated by augmentation in the longitudinal perspective and causal link. Conclusions We showed the relation between attendance at cultural events and self-reported health could only be confirmed as associational. Therefore, this study provided little justification to encourage use

Complementary methods to study glasses and melts at large scale facilities

International Nuclear Information System (INIS)

Leydier, M.

2010-01-01

In this work, large scale facilities (neutron and synchrotron sources) were used for studying the structure and dynamic of disordered materials (liquids and glasses). In particular, three studies are presented. The first is a structural study of Ln 2 O 3 -Al 2 O 3 -SiO 2 glasses where Ln represents the cations Sc, Y and La. We combined the results obtained from x-ray and neutron diffraction and x-ray absorption experiments. This work is focused on the determination of the interatomic distances and coordination numbers for the three pairs Si-O, Al-O and Ln-O. The second is a study of the iron oxide FeO in the liquid state. Photoemission experiments at the iron absorption edge were associated with x-ray and neutron diffraction measurements. The results obtained made it possible to define a consistent structural model for liquid FeO. The third is a study of the dynamics in CaAl 2 O 4 melts. From inelastic x-ray scattering experiments, it was possible to determine the apparent and isothermal sound velocities as well as the longitudinal viscosity. These measurements were complemented by quasielastic neutron scattering experiments from which atomic diffusion coefficients were determined. This work shows the interest of combining various experimental techniques for studying glasses and melts and points out the need to associate also modelling techniques such as molecular dynamics simulations. (author)

A Longitudinal Study on Resting State Functional Connectivity in Behavioral Variant Frontotemporal Dementia and Alzheimer's Disease.

Science.gov (United States)

Hafkemeijer, Anne; Möller, Christiane; Dopper, Elise G P; Jiskoot, Lize C; van den Berg-Huysmans, Annette A; van Swieten, John C; van der Flier, Wiesje M; Vrenken, Hugo; Pijnenburg, Yolande A L; Barkhof, Frederik; Scheltens, Philip; van der Grond, Jeroen; Rombouts, Serge A R B

2017-01-01

Alzheimer's disease (AD) and behavioral variant frontotemporal dementia (bvFTD) are the most common types of early-onset dementia. We applied longitudinal resting state functional magnetic resonance imaging (fMRI) to delineate functional brain connections relevant for disease progression and diagnostic accuracy. We used two-center resting state fMRI data of 20 AD patients (65.1±8.0 years), 12 bvFTD patients (64.7±5.4 years), and 22 control subjects (63.8±5.0 years) at baseline and 1.8-year follow-up. We used whole-network and voxel-based network-to-region analyses to study group differences in functional connectivity at baseline and follow-up, and longitudinal changes in connectivity within and between groups. At baseline, connectivity between paracingulate gyrus and executive control network, between cuneal cortex and medial visual network, and between paracingulate gyrus and salience network was higher in AD compared with controls. These differences were also present after 1.8 years. At follow-up, connectivity between angular gyrus and right frontoparietal network, and between paracingulate gyrus and default mode network was lower in bvFTD compared with controls, and lower compared with AD between anterior cingulate gyrus and executive control network, and between lateral occipital cortex and medial visual network. Over time, connectivity decreased in AD between precuneus and right frontoparietal network and in bvFTD between inferior frontal gyrus and left frontoparietal network. Longitudinal changes in connectivity between supramarginal gyrus and right frontoparietal network differ between both patient groups and controls. We found disease-specific brain regions with longitudinal connectivity changes. This suggests the potential of longitudinal resting state fMRI to delineate regions relevant for disease progression and for diagnostic accuracy, although no group differences in longitudinal changes in the direct comparison of AD and bvFTD were found.

Comparison of modified driver circuit and capacitor-transfer circuit in longitudinally excited N2 laser.

Science.gov (United States)

Uno, Kazuyuki; Akitsu, Tetsuya; Nakamura, Kenshi; Jitsuno, Takahisa

2013-04-01

We developed a modified driver circuit composed of a capacitance and a spark gap, called a direct-drive circuit, for a longitudinally excited gas laser. The direct-drive circuit uses a large discharge impedance caused by a long discharge length of the longitudinal excitation scheme and eliminates the buffer capacitance used in the traditional capacitor-transfer circuit. We compared the direct-drive circuit and the capacitor-transfer circuit in a longitudinally excited N2 laser (wavelength: 337 nm). Producing high output energy with the capacitor-transfer circuit requires a large storage capacitance and a discharge tube with optimum dimensions (an inner diameter of 4 mm and a length of 10 cm in this work); in contrast, the direct-drive circuit requires a high breakdown voltage, achieved with a small storage capacitance and a large discharge tube. Additionally, for the same input energy of 792 mJ, the maximum output energy of the capacitor-transfer circuit was 174.2 μJ, and that of the direct-drive circuit was 344.7 μJ.

A cohort study of leisure time physical activity and depression

DEFF Research Database (Denmark)

Mikkelsen, Stine Schou; Tolstrup, Janne Schumann; Flachs, Esben Meulengracht

2010-01-01

The objective of the study was to examine the role of leisure time physical activity on the risk of developing depression in a large longitudinal setting.......The objective of the study was to examine the role of leisure time physical activity on the risk of developing depression in a large longitudinal setting....

A Longitudinal Study of Adolescent Internet Addiction: The Role of Conscientiousness and Classroom Hostility

Science.gov (United States)

Stavropoulos, Vasilis; Kuss, Daria; Griffiths, Mark; Motti-Stefanidi, Frosso

2016-01-01

Over the last decade, research on Internet addiction (IA) has increased. However, almost all studies in the area are cross-sectional and do not examine the context in which Internet use takes place. Therefore, a longitudinal study examined the role of conscientiousness (as a personality trait) and classroom hostility (as a contextual factor) in…

Fatigue life of bovine meniscus under longitudinal and transverse tensile loading.

Science.gov (United States)

Creechley, Jaremy J; Krentz, Madison E; Lujan, Trevor J

2017-05-01

The knee meniscus is composed of a fibrous extracellular matrix that is subjected to large and repeated loads. Consequently, the meniscus is frequently torn, and a potential mechanism for failure is fatigue. The objective of this study was to measure the fatigue life of bovine meniscus when applying cyclic tensile loads either longitudinal or transverse to the principal fiber direction. Fatigue experiments consisted of cyclic loads to 60%, 70%, 80% or 90% of the predicted ultimate tensile strength until failure occurred or 20,000 cycles was reached. The fatigue data in each group was fit with a Weibull distribution to generate plots of stress level vs. cycles to failure (S-N curve). Results showed that loading transverse to the principal fiber direction gave a two-fold increase in failure strain, a three-fold increase in creep, and a nearly four-fold increase in cycles to failure (not significant), compared to loading longitudinal to the principal fiber direction. The S-N curves had strong negative correlations between the stress level and the mean cycles to failure for both loading directions, where the slope of the transverse S-N curve was 11% less than the longitudinal S-N curve (longitudinal: S=108-5.9ln(N); transverse: S=112-5.2ln(N)). Collectively, these results suggest that the non-fibrillar matrix is more resistant to fatigue failure than the collagen fibers. Results from this study are relevant to understanding the etiology of atraumatic radial and horizontal meniscal tears, and can be utilized by research groups that are working to develop meniscus implants with fatigue properties that mimic healthy tissue. Copyright © 2017 Elsevier Ltd. All rights reserved.

Project STARS (Studies on Trajectories of Adolescent Relationships and Sexuality) : A longitudinal, multi-domain study on sexual development of Dutch adolescents

NARCIS (Netherlands)

Reitz, Ellen; van de Bongardt, Daphne; Baams, Laura; Doornwaard, Suzan; Dalenberg, Wieke; Dubas, Judith; van Aken, Marcel; Overbeek, Geertjan; ter Bogt, Tom; van den Eijnden, Regina; Vanwesenbeeck, Wilhelmina; Kunnen, Saskia; Timmerman, Greetje; van Geert, Paul; Deković, Maja

2015-01-01

This study gives an overview of Project STARS (Studies on Trajectories of Adolescent Relationships and Sexuality), a four-wave longitudinal study of 1297 Dutch adolescents. First, the sample, measures and four sub-projects are described. Second, hierarchical regression analyses were conducted to

Project STARS (Studies on Trajectories of Adolescent Relationships and Sexuality): A longitudinal, multi-domain study on sexual development of Dutch adolescents

NARCIS (Netherlands)

Reitz, E.; van de Bongardt, D.; Baams, L.; Doornwaard, S.; Dalenberg, W.; Dubas, J.; van Aken, M.; Overbeek, G.; ter Bogt, T.; van der Eijnden, R.; Vanwesenbeeck, I.; Kunnen, S.; Timmerman, G.; van Geert, P.; Deković, M.

2015-01-01

This study gives an overview of Project STARS (Studies on Trajectories of Adolescent Relationships and Sexuality), a four-wave longitudinal study of 1297 Dutch adolescents. First, the sample, measures and four sub-projects are described. Second, hierarchical regression analyses were conducted to

The CogBIAS longitudinal study protocol: cognitive and genetic factors influencing psychological functioning in adolescence.

Science.gov (United States)

Booth, Charlotte; Songco, Annabel; Parsons, Sam; Heathcote, Lauren; Vincent, John; Keers, Robert; Fox, Elaine

2017-12-29

Optimal psychological development is dependent upon a complex interplay between individual and situational factors. Investigating the development of these factors in adolescence will help to improve understanding of emotional vulnerability and resilience. The CogBIAS longitudinal study (CogBIAS-L-S) aims to combine cognitive and genetic approaches to investigate risk and protective factors associated with the development of mood and impulsivity-related outcomes in an adolescent sample. CogBIAS-L-S is a three-wave longitudinal study of typically developing adolescents conducted over 4 years, with data collection at age 12, 14 and 16. At each wave participants will undergo multiple assessments including a range of selective cognitive processing tasks (e.g. attention bias, interpretation bias, memory bias) and psychological self-report measures (e.g. anxiety, depression, resilience). Saliva samples will also be collected at the baseline assessment for genetic analyses. Multilevel statistical analyses will be performed to investigate the developmental trajectory of cognitive biases on psychological functioning, as well as the influence of genetic moderation on these relationships. CogBIAS-L-S represents the first longitudinal study to assess multiple cognitive biases across adolescent development and the largest study of its kind to collect genetic data. It therefore provides a unique opportunity to understand how genes and the environment influence the development and maintenance of cognitive biases and provide insight into risk and protective factors that may be key targets for intervention.

Actively adjustable step-type ultrasonic horns in longitudinal vibration

Science.gov (United States)

Lin, Shuyu; Guo, Hao; Xu, Jie

2018-04-01

Actively adjustable longitudinal step-type ultrasonic horns are proposed and studied. The horn is composed of a traditional ultrasonic horn and piezoelectric material. In practical applications, this kind of step-type ultrasonic horn is mechanically excited by an ultrasonic transducer and the piezoelectric material is connected to an adjustable electric impedance. In this research, the effects of the electric impedance and of the location of the piezoelectric material on the performance of the horn are studied. It is shown that when the electric resistance is increased, the resonance frequency of the horn is increased; the displacement magnification is increased when the piezoelectric material is located in the large end and decreased when the piezoelectric material is located in the small end of the horn. The displacement magnification for the piezoelectric material in the large end is larger than that for the piezoelectric material in the small end of the horn. Some step-type ultrasonic horns are designed and manufactured; the resonance frequency and the displacement magnification are measured by means of POLYTEC Laser Scanning vibrometer. It is shown that the theoretical resonance frequency and the displacement magnification are in good agreement with the measured results. It is concluded that by means of the insertion of the piezoelectric material in the longitudinal horn, the horn performance can be adjusted by changing the electric impedance and the location of the piezoelectric material in the horn. It is expected that this kind of adjustable ultrasonic horns can be used in traditional and potential ultrasonic technologies where the vibrational performance adjustment is needed.

Adapting an evidence-based model to retain adolescent study participants in longitudinal research.

Science.gov (United States)

Davis, Erin; Demby, Hilary; Jenner, Lynne Woodward; Gregory, Alethia; Broussard, Marsha

2016-02-01

Maintaining contact with and collecting outcome data from adolescent study participants can present a significant challenge for researchers conducting longitudinal studies. Establishing an organized and effective protocol for participant follow-up is crucial to reduce attrition and maintain high retention rates. This paper describes our methods in using and adapting the evidence-based Engagement, Verification, Maintenance, and Confirmation (EVMC) model to follow up with adolescents 6 and 12 months after implementation of a health program. It extends previous research by focusing on two key modifications to the model: (1) the central role of cell phones and texting to maintain contact with study participants throughout the EVMC process and, (2) use of responsive two-way communication between staff and participants and flexible administration modes and methods in the confirmation phase to ensure that busy teens not only respond to contacts, but also complete data collection. These strategies have resulted in high overall retention rates (87-91%) with adolescent study participants at each follow-up data collection point without the utilization of other, more involved tracking measures. The methods and findings presented may be valuable for other researchers with limited resources planning for or engaged in collecting follow-up outcome data from adolescents enrolled in longitudinal studies. Copyright © 2015. Published by Elsevier Ltd.

ABRUPT LONGITUDINAL MAGNETIC FIELD CHANGES IN FLARING ACTIVE REGIONS

International Nuclear Information System (INIS)

Petrie, G. J. D.; Sudol, J. J.

2010-01-01

We characterize the changes in the longitudinal photospheric magnetic field during 38 X-class and 39 M-class flares within 65 0 of disk center using 1 minute GONG magnetograms. In all 77 cases, we identify at least one site in the flaring active region where clear, permanent, stepwise field changes occurred. The median duration of the field changes was about 15 minutes and was approximately equal for X-class and for M-class flares. The absolute values of the field changes ranged from the detection limit of ∼10 G to as high as ∼450 G in two exceptional cases. The median value was 69 G. Field changes were significantly stronger for X-class than for M-class flares and for limb flares than for disk-center flares. Longitudinal field changes less than 100 G tended to decrease longitudinal field strengths, both close to disk center and close to the limb, while field changes greater than 100 G showed no such pattern. Likewise, longitudinal flux strengths tended to decrease during flares. Flux changes, particularly net flux changes near disk center, correlated better than local field changes with GOES peak X-ray flux. The strongest longitudinal field and flux changes occurred in flares observed close to the limb. We estimate the change of Lorentz force associated with each flare and find that this is large enough in some cases to power seismic waves. We find that longitudinal field decreases would likely outnumber increases at all parts of the solar disk within 65 0 of disk center, as in our observations, if photospheric field tilts increase during flares as predicted by Hudson et al.

Is the naturalistic course of depression in older people related to received support over time? Results from a longitudinal population-based study

NARCIS (Netherlands)

Houtjes, W.; Deeg, D.J.H.; van de Ven, P.M.; van Meijel, B.; van Tilburg, T.G.; Beekman, A.T.F.

Objectives: To test the interrelation of the naturalistic course of depression in older people with long-term support received. Design: Longitudinal cohort study. Methods: A sample of 277 adults age 55-85years participating in the Longitudinal Aging Study Amsterdam, with clinically relevant

Marital transitions and life satisfaction: Evidence from longitudinal data from Norway

OpenAIRE

Næss, Siri; Blekesaune, Morten; Jakobsson, Niklas

2014-01-01

This article is based on three waves of data collected by the Nord-Trøndelag Health Study (HUNT), Norway. It investigates changes in life satisfaction associated with transition both into and out of marital unions (marriages and cohabitations). It provides longitudinal data on life satisfaction for a larger sample (N¼57,446), a longer age span (19–101 years) and over a longer observation period (22 years) than previously published research on this topic. The large sample permits interaction a...

Azimuthal asymmetries in semi-inclusive deep-inelastic hadron muoproduction on longitudinally polarized protons

Energy Technology Data Exchange (ETDEWEB)

Sirtl, Stefan

2016-06-27

In recent years, measuring azimuthal asymmetries in semi-inclusive deep-inelastic scattering (SIDIS) off polarized targets emerged as a powerful tool to investigate the nucleon spin structure, one of the main objectives of the COMPASS physics program. The two-stage COMPASS spectrometer at the CERN SPS is characterized by a large acceptance and a broad kinematic coverage. It makes use of a tertiary longitudinally polarized high-energetic μ{sup +} beam, impinging on a transversely or longitudinally polarized ammonia target. This thesis is dedicated to the analysis of both leading and subleading longitudinal target spin dependent asymmetries arising in the SIDIS cross section of one hadron and hadron pair production. The results provide new insights to the longitudinal spin structure of the nucleon, addressing the role of spin-orbit couplings and quark-gluon correlations in the framework of collinear or transverse momentum dependent factorization.

Confounding adjustment through front-door blocking in longitudinal studies

Directory of Open Access Journals (Sweden)

Arvid Sjölander

2013-03-01

Full Text Available A common aim of epidemiological research is to estimate the causal effect of a particular exposure on a particular outcome. Towards this end, observed associations are often ‘adjusted’ for potential confounding variables. When the potential confounders are unmeasured, explicit adjustment becomes unfeasible. It has been demonstrated that causal effects can be estimated even in the presence of umeasured confounding, utilizing a method called ‘front-door blocking’. In this paper we generalize this method to longitudinal studies. We demonstrate that the method of front-door blocking poses a number of challenging statistical problems, analogous to the famous problems associ- ated with the method of ‘back-door blocking’.

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

Science.gov (United States)

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

Longitudinal trends in gasoline price and physical activity: The CARDIA study

Science.gov (United States)

Hou, Ningqi; Popkin, Barry M; Jacobs, David R; Song, Yan; Guilkey, David K; He, Ka; Lewis, Cora E.; Gordon-Larsen, Penny

2011-01-01

Objective To investigate longitudinal associations between community-level gasoline price and physical activity (PA). Method In the Coronary Artery Risk Development in Young Adults study, 5,115 black and white participants aged 18–30 at baseline 1985–86 were recruited from four U.S. cities (Birmingham, Chicago, Minneapolis and Oakland) and followed over time. We used data from 3 follow-up exams: 1992–93, 1995–96, and 2000–01, when the participants were located across 48 states. From questionnaire data, a total PA score was summarized in exercise units (EU) based on intensity and frequency of 13 PA categories. Using Geographic Information Systems, participants’ residential locations were linked to county-level inflation-adjusted gasoline price data collected by the Council for Community & Economic Research. We used a random-effect longitudinal regression model to examine associations between time-varying gasoline price and time-varying PA, controlling for age, race, gender, baseline study center, and time-varying education, marital status, household income, county cost of living, county bus fare, census block-group poverty, and urbanicity. Results Holding all control variables constant, a 25-cent increase in inflation-adjusted gasoline price was significantly associated with an increase of 9.9 EU in total PA (95%CI: 0.8–19.1). Conclusion Rising prices of gasoline may be associated with an unintended increase in leisure PA. PMID:21338621

Impact of Residential Mobility on Exposure Assessment in Longitudinal Air Pollution Studies: A Sensitivity Analysis within the ESCAPE Project

Directory of Open Access Journals (Sweden)

Anna Oudin

2012-01-01

Full Text Available Exposure misclassification in longitudinal studies of air pollution exposure and health effects can occur due to residential mobility in a study population over followup. The aim of this study was to investigate to what extent residential mobility during followup can be expected to cause exposure misclassification in such studies, where exposure at the baseline address is used as the main exposure assessment. The addresses for each participant in a large population-based study (N>25,000 were obtained via national registers. We used a Land Use Regression model to estimate the NOx concentration for each participant's all addresses during the entire follow-up period (in average 14.6 years and calculated an average concentration during followup. The Land Use Regression model explained 83% of the variation in measured levels. In summary, the NOx concentration at the inclusion address was similar to the average concentration over followup with a correlation coefficient of 0.80, indicating that air pollution concentration at study inclusion address could be used as indicator of average air pollution concentrations over followup. The differences between an individual's inclusion and average follow-up mean concentration were small and seemed to be nondifferential with respect to a large range of factors and disease statuses, implying that bias due to residential mobility was small.

Control of longitudinal collective behavior in the Muon Collider rings

International Nuclear Information System (INIS)

Cheng, Wen-Hao

1997-05-01

The longitudinal bunch collective effects in a Muon Collider ring are theoretically examined. The situation involves an intense bunch, a short bunch, a small momentum compaction, a rather large impedance compared with the stability threshold criterion, and luminosity life time limited by muon decay to a thousand turns. Qualitative descriptions of stability are given and a scaling law for the instability threshold is derived. Numerical simulation results for the impedance-related instabilities are given for two cases of current interest - a 250 GeV x 250 GeV demonstration machine and a 2 TeV x 2 TeV high energy machine. The results of these simulations are in good agreement with the predictions of the scaling law and show that the longitudinal collective effects are controllable with a proper choice of parameters (viz. rf voltage, rf frequency, linear and non-linear longitudinal chromaticity)

Team turnover and task conflict: A longitudinal study on the moderating effects of collective experience

NARCIS (Netherlands)

Kuypers, A.P.A.; Günter, H.; van Emmerik, I.H.

2015-01-01

Team turnover can be harmful to a team in many ways. This study examined whether a team’s collective experience (team organizational tenure) attenuates the association between team turnover and task conflict changes. Differing from prior research, our study used a longitudinal design to assess the

Chocolate intake is associated with better cognitive function: The Maine-Syracuse Longitudinal Study.

Science.gov (United States)

Crichton, Georgina E; Elias, Merrill F; Alkerwi, Ala'a

2016-05-01

Chocolate and cocoa flavanols have been associated with improvements in a range of health complaints dating from ancient times, and has established cardiovascular benefits. Less is known about the effects of chocolate on neurocognition and behaviour. The aim of this study was to investigate whether chocolate intake was associated with cognitive function, with adjustment for cardiovascular, lifestyle and dietary factors. Cross-sectional analyses were undertaken on 968 community-dwelling participants, aged 23-98 years, from the Maine-Syracuse Longitudinal Study (MSLS). Habitual chocolate intake was related to cognitive performance, measured with an extensive battery of neuropsychological tests. More frequent chocolate consumption was significantly associated with better performance on the Global Composite score, Visual-Spatial Memory and Organization, Working Memory, Scanning and Tracking, Abstract Reasoning, and the Mini-Mental State Examination. With the exception of Working Memory, these relations were not attenuated with statistical control for cardiovascular, lifestyle and dietary factors. Prospective analyses revealed no association between cognitive function and chocolate intake measured up to 18 years later. Further intervention trials and longitudinal studies are needed to explore relations between chocolate, cocoa flavanols and cognition, and the underlying causal mechanisms. Copyright © 2016 Elsevier Ltd. All rights reserved.

Longitudinal instability studies at the SURF II storage ring at NIST

International Nuclear Information System (INIS)

Harkay, K.C.; Sereno, N.S.

1998-01-01

Measurements of the longitudinal instability observed in the storage ring at the Synchrotrons Ultraviolet Radiation Facility (SURF II) at the National Institute of Standards and Technology (NET) were performed to understand the mechanism driving the instability. The instability, studied in depth by Ralcowsky and others, manifests itself in broad resonance features in the horizontal and vertical motion spectrum of the synchrotrons light from DC to a few kHz. Also observed are multiple synchrotrons harmonics that modulate the revolution harmonics; these are characteristic of longitudinal phase oscillations. These spectral features of the motion are found to be correlated with the periodic lengthening and shortening of the bunch length on time scales from approximately0.1 ms to 20 ms, depending on machine and radio-frequency (rf) system parameters. In this report, the growth rate of the instability is determined from measurements using an rf pickup electrode. The measured growth rates are compared to computed growth rates from an analytical model. Recommendations are made regarding options to control or mitigate the instability. In light of upgrade plans for SURF III, a few comments are presented about the beam lifetime

Tricritical behavior in the diluted transverse spin-1 Ising model with a longitudinal crystal field

International Nuclear Information System (INIS)

Htoutou, K.; Oubelkacem, A.; Ainane, A.; Saber, M.

2005-01-01

The transverse spin-1 Ising model with a longitudinal crystal field exhibits a tricritical behavior. Within the effective field theory with a probability distribution technique that accounts for the self-spin correlations, we have studied the influence of site dilution on this behavior and have calculated the temperature-transverse field-longitudinal crystal field-concentration phase diagrams and determined, in particular, the influence of the concentration of magnetic atoms c on the tricritical behavior. We have found that the tricritical point appears for large values of the concentration c of magnetic atoms and disappears with the increase in dilution (small values of c). Results for square lattice are calculated numerically and some interesting results are obtained. In certain ranges of values of the strength of the longitudinal crystal field D/J when it becomes sufficiently negative, we found re-entrant phenomenon, which disappears with increase in the value of the strength of the transverse field

Laser wakefield excitation and measurement by femtosecond longitudinal interferometry

International Nuclear Information System (INIS)

Siders, C.W.; Le Blanc, S.P.; Fisher, D.; Tajima, T.; Downer, M.C.

1996-04-01

Plasma density oscillations (Langmuir waves) in the wake of an intense (I peak ∼ 3 x 10 17 W/cm 2 ) laser pulse (100 fs) are measured with ultrafast time resolution using a longitudinal interferometric technique. Phase shifts consistent with large amplitude (δn e /n e ∼ 1) density waves at the electron plasma frequency were observed in a fully tunnel-ionized He plasma, corresponding to longitudinal electric fields of ∼ 10 GV/m. Strong radial ponderomotive forces enhance the density oscillations. As this technique utilizes a necessary component of any laser-based plasma accelerator, it promises to be a powerful tool for on-line monitoring and control of future plasma-based particle accelerators

Parental influences on adolescent physical activity: a longitudinal study

Directory of Open Access Journals (Sweden)

Ayala Guadalupe X

2007-02-01

Full Text Available Abstract Background Physical inactivity is increasing among adolescents in the U.S., especially among girls. Despite growing evidence that parents are an important influence on adolescent health, few longitudinal studies have explored the causal relationship between parental influence and physical activity. This study examines how the relationships between parental influences and adolescent physical activity differ by gender and tests whether these relationships are mediated by adolescents' self-esteem and depression. Methods Data are from the National Longitudinal Study of Adolescent Health. The sample includes 13,246 youth, grades 7 to 12, interviewed in 1995 and again 1 year later. Logit models were used to evaluate parental influences on achieving five or more bouts of moderate to vigorous physical activity per week [MVPA] and whether the relationship between parental influence and MVPA was mediated by adolescents' level of self-esteem and depression. Results Family cohesion, parent-child communication and parental engagement positively predicted MVPA for both genders one year later (odds ratios and 95% confidence intervals for females, 1.09 [1.05–1.12], 1.13 [1.07–1.19], 1.25 [1.17–1.33] and males, 1.08 [1.04–1.11], 1.14 [1.07–1.23], 1.23 [1.14–1.33], respectively; however, parental monitoring did not (odds ratio and confidence intervals for females and males, 1.02 [.97–1.07]. For both females and males, self-esteem mediated the relationship between parental influence and physical activity. Depressive symptoms were only a mediator among males. Females reported higher levels of parent-child communication and lower family cohesion compared with males. There were no gender differences in levels of parental monitoring and engagement. Females had significantly lower levels of self-esteem and higher levels of depressive symptoms than males. Conclusion Strategies to promote physical activity among adolescents should focus on

Pump-probe studies of travelling coherent longitudinal acoustic phonon oscillations in GaAs

Energy Technology Data Exchange (ETDEWEB)

Xu, Y.; Qi, J.; Tolk, Norman [Department of Physics and Astronomy, Vanderbilt University, Nashville, TN, 37235 (United States); Miller, J. [Naval air Warfare Center Weapons Division, China Lake, CA 93555 (United States); Cho, Y.J.; Liu, X.; Furdyna, J.K. [Department of Physics, University of Notre Dame, Notre Dame, IN 46556 (United States); Shahbazyan, T.V. [Department of Physics, Jackson State University, MS 39217 (United States)

2008-07-01

We report comprehensive studies of long-lived oscillations in femtosecond optical pump-probe measurements on GaAs based systems. The oscillations arise from a photo-generated coherent longitudinal acoustic phonon wave at the sample surface, which subsequently travels from the surface into the GaAs substrate, thus providing information on the optical properties of the material as a function of time/depth. Wavelength-dependent studies of the oscillations near the bandgap of GaAs indicate strong correlations to the optical properties of GaAs. We also use the coherent longitudinal acoustic phonon waves to probe a thin buried Ga{sub 0.1}In{sub 0.9}As layers non-invasively. The observed phonon oscillations experience a reduction in amplitude and a phase change at wavelengths near the bandgap of the GaAs, when it passes through the thin Ga{sub x}In{sub 1-x}As layer. The layer depth and thicknesses can be extracted from the oscillation responses. A model has been developed that satisfactorily characterizes the experimental results. (copyright 2008 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Longitudinal study of self-awakening and sleep/wake habits in adolescents

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Ikeda H

2012-09-01

Full Text Available Hiroki Ikeda,1 Mitsuo Hayashi21Department of Adult Mental Health, National Institute of Mental Health, National Center of Neurology and Psychiatry, Tokyo; 2Department of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Hiroshima, JapanAbstract: Self-awakening is the ability to awaken without external assistance at a predetermined time. Cross-sectional studies reported that people who self-awaken have sleep/wake habits different from those of people who use external means to wake from sleep. However, no longitudinal study has examined self-awakening. The present study investigated self-awakening, both habitual and inconsistent, compared to awakening by external means in relation to sleep/wake schedules for five consecutive years in 362 students (starting at mean age 15.1 ± 0.3 years. Students who self-awakened consistently for five consecutive years (5% of all students went to bed earlier than those who inconsistently self-awakened (mixed group, 40% or consistently used forced awakening by external means (56%. Awakening during sleep was more frequent and sleep was lighter in the consistently self-awakened group than in the mixed and consistently forced-awakened groups. However, daytime dozing was less frequent and comfort immediately after awakening was greater for the consistently self-awakened group than for the mixed and consistently forced-awakened groups. These results indicate that the three groups have different sleep/wake habits. Previous studies of self-awakening using cross-sectional survey data may have confounded both consistent and inconsistent self-awakening habits. A longitudinal study is necessary to clarify the relationship between the self-awakening habit and sleep/wake patterns.Keywords: habitual self-awakening, sleep/wake pattern, adolescent

Removing Batch Effects from Longitudinal Gene Expression - Quantile Normalization Plus ComBat as Best Approach for Microarray Transcriptome Data.

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Christian Müller

Full Text Available Technical variation plays an important role in microarray-based gene expression studies, and batch effects explain a large proportion of this noise. It is therefore mandatory to eliminate technical variation while maintaining biological variability. Several strategies have been proposed for the removal of batch effects, although they have not been evaluated in large-scale longitudinal gene expression data. In this study, we aimed at identifying a suitable method for batch effect removal in a large study of microarray-based longitudinal gene expression. Monocytic gene expression was measured in 1092 participants of the Gutenberg Health Study at baseline and 5-year follow up. Replicates of selected samples were measured at both time points to identify technical variability. Deming regression, Passing-Bablok regression, linear mixed models, non-linear models as well as ReplicateRUV and ComBat were applied to eliminate batch effects between replicates. In a second step, quantile normalization prior to batch effect correction was performed for each method. Technical variation between batches was evaluated by principal component analysis. Associations between body mass index and transcriptomes were calculated before and after batch removal. Results from association analyses were compared to evaluate maintenance of biological variability. Quantile normalization, separately performed in each batch, combined with ComBat successfully reduced batch effects and maintained biological variability. ReplicateRUV performed perfectly in the replicate data subset of the study, but failed when applied to all samples. All other methods did not substantially reduce batch effects in the replicate data subset. Quantile normalization plus ComBat appears to be a valuable approach for batch correction in longitudinal gene expression data.

Caregiver Self-Esteem as a Predictor of Patient Relationship Satisfaction: A Longitudinal Study.

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Mroz, Emily L; Poulin, Michael J; Grant, Pei C; Depner, Rachel M; Breier, Jennifer; Byrwa, David J; Wright, Scott T

2018-03-01

Longitudinal assessment of patient-caregiver relationships will determine whether caregiver self-esteem determines patient relationship satisfaction at end of life. Research on close relationships and caregiving supports the idea that informal caregivers' self-esteem may influence their relationships with their terminally ill loved ones. However, this connection has not yet been investigated longitudinally, nor has it been applied specifically to care recipients' relationship satisfaction. A sample of 24 caregivers and 24 patients in a hospice home care program were recruited. Multiple patient and caregiver interviews were used to conduct a longitudinal study to measure fluctuations in patient health, changes in patient and caregiver relationship satisfaction, and self-esteem over a three-month period. An interaction between caregiver self-esteem and patient relationship satisfaction demonstrated the role that self-esteem plays between caregivers and patients enrolled in hospice care. Specifically, for patients with caregivers with low self-esteem, patient relationship satisfaction significantly decreased as the patient's physical health decreased, whereas for patients whose caregivers had high self-esteem, patient relationship satisfaction marginally increased during poorer physical health. High self-esteem may allow caregivers to overcome feelings of burden and maladaptive anticipatory grief to remain satisfied in their relationship with the patient. Caregiver self-esteem appears to play a role in fostering patient relationship satisfaction at the end of life.

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

Energy Technology Data Exchange (ETDEWEB)

Garg, Akash Deep, E-mail: akash-deep@rrcat.gov.in [Beam Diagnostics Section (BDS), Indus Operations, Beam Dynamics and Diagnostics Division (IOBDD), Raja Ramanna Centre for Advanced Technology, Indore 452 013, M.P. (India); Homi Bhabha National Institute (HBNI) at Raja Ramanna Centre for Advanced Technology, Indore (India); Yadav, S.; Kumar, Mukesh; Shrivastava, B.B.; Karnewar, A.K.; Ojha, A.; Puntambekar, T.A. [Beam Diagnostics Section (BDS), Indus Operations, Beam Dynamics and Diagnostics Division (IOBDD), Raja Ramanna Centre for Advanced Technology, Indore 452 013, M.P. (India)

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.

Research on fatigue behavior and residual stress of large-scale cruciform welding joint with groove

International Nuclear Information System (INIS)

Zhao, Xiaohui; Liu, Yu; Liu, Yong; Gao, Yuan

2014-01-01

Highlights: • The fatigue behavior of the large-scale cruciform welding joint with groove was studied. • The longitudinal residual stress of the large-scale cruciform welding joint was tested by contour method. • The fatigue fracture mechanism of the large-scale cruciform welding joint with groove was analyzed. - Abstract: Fatigue fracture behavior of the 30 mm thick Q460C-Z steel cruciform welded joint with groove was investigated. The fatigue test results indicated that fatigue strength of 30 mm thick Q460C-Z steel cruciform welded joint with groove can reach fatigue level of 80 MPa (FAT80). Fatigue crack source of the failure specimen initiated from weld toe. Meanwhile, the microcrack was also found in the fusion zones of the fatigue failure specimen, which was caused by weld quality and weld metal integrity resulting from the multi-pass welds. Two-dimensional map of the longitudinal residual stress of 30 mm thick Q460C-Z steel cruciform welded joint with groove was obtained by using the contour method. The stress nephogram of Two-dimensional map indicated that longitudinal residual stress in the welding center is the largest

Temporal divergence of percent body fat and body mass index in pre-teenage children: the LOOK longitudinal study.

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Telford, R D; Cunningham, R B; Abhayaratna, W P

2014-12-01

The index of body mass related to stature, (body mass index, BMI, kgm(-2) ), is widely used as a proxy for percent body fat (%BF) in cross-sectional and longitudinal investigations. BMI does not distinguish between lean and fat mass and in children, the cross-sectional relationship between %BF and BMI changes with age and sex. While BMI increases linearly with age from age 8 to 12 years in both boys and girls, %BF plateaus off between 10 and 12 years. Repeated measures in children show a systematic decrease in %BF for any given BMI from age 8 to 10 to 12 years. Because changes in BMI misrepresent changes in %BF, its use as a proxy of %BF should be avoided in longitudinal studies in this age group. Body mass index (BMI, kgm(-2) ) is commonly used as an indicator of pediatric adiposity, but with its inability to distinguish changes in lean and fat mass, its use in longitudinal studies of children requires careful consideration. To investigate the suitability of BMI as a surrogate of percent body fat (%BF) in pediatric longitudinal investigations. In this longitudinal study, healthy Australian children (256 girls and 278 boys) were measured at ages 8.0 (standard deviation 0.3), 10.0 and 12.0 years for height, weight and percent body fat (%BF) by dual-energy X-ray absorptiometry. The patterns of change in the means of %BF and BMI were different (P < 0.001). While mean BMI increased linearly from 8 to 12 years of age, %BF did not change between 10 and 12 years. Relationships between %BF and BMI in boys and girls were curvilinear and varied with age (P < 0.001) and gender (P < 0.001); any given BMI corresponding with a lower %BF as a child became older. Considering the divergence of temporal patterns of %BF and BMI between 10 and 12 years of age, employment of BMI as a proxy for %BF in absolute or age and sex standardized forms in pediatric longitudinal investigations is problematical. © 2013 The Authors. Pediatric Obesity © 2013 International Association

Modelling variable dropout in randomised controlled trials with longitudinal outcomes: application to the MAGNETIC study.

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Kolamunnage-Dona, Ruwanthi; Powell, Colin; Williamson, Paula Ruth

2016-04-28

Clinical trials with longitudinally measured outcomes are often plagued by missing data due to patients withdrawing or dropping out from the trial before completing the measurement schedule. The reasons for dropout are sometimes clearly known and recorded during the trial, but in many instances these reasons are unknown or unclear. Often such reasons for dropout are non-ignorable. However, the standard methods for analysing longitudinal outcome data assume that missingness is non-informative and ignore the reasons for dropout, which could result in a biased comparison between the treatment groups. In this article, as a post hoc analysis, we explore the impact of informative dropout due to competing reasons on the evaluation of treatment effect in the MAGNETIC trial, the largest randomised placebo-controlled study to date comparing the addition of nebulised magnesium sulphate to standard treatment in acute severe asthma in children. We jointly model longitudinal outcome and informative dropout process to incorporate the information regarding the reasons for dropout by treatment group. The effect of nebulised magnesium sulphate compared with standard treatment is evaluated more accurately using a joint longitudinal-competing risk model by taking account of such complexities. The corresponding estimates indicate that the rate of dropout due to good prognosis is about twice as high in the magnesium group compared with standard treatment. We emphasise the importance of identifying reasons for dropout and undertaking an appropriate statistical analysis accounting for such dropout. The joint modelling approach accounting for competing reasons for dropout is proposed as a general approach for evaluating the sensitivity of conclusions to assumptions regarding missing data in clinical trials with longitudinal outcomes. EudraCT number 2007-006227-12 . Registration date 18 Mar 2008.

Understanding developmental language disorder - the Helsinki longitudinal SLI study (HelSLI): a study protocol.

Science.gov (United States)

Laasonen, Marja; Smolander, Sini; Lahti-Nuuttila, Pekka; Leminen, Miika; Lajunen, Hanna-Reetta; Heinonen, Kati; Pesonen, Anu-Katriina; Bailey, Todd M; Pothos, Emmanuel M; Kujala, Teija; Leppänen, Paavo H T; Bartlett, Christopher W; Geneid, Ahmed; Lauronen, Leena; Service, Elisabet; Kunnari, Sari; Arkkila, Eva

2018-05-21

Developmental language disorder (DLD, also called specific language impairment, SLI) is a common developmental disorder comprising the largest disability group in pre-school-aged children. Approximately 7% of the population is expected to have developmental language difficulties. However, the specific etiological factors leading to DLD are not yet known and even the typical linguistic features appear to vary by language. We present here a project that investigates DLD at multiple levels of analysis and aims to make the reliable prediction and early identification of the difficulties possible. Following the multiple deficit model of developmental disorders, we investigate the DLD phenomenon at the etiological, neural, cognitive, behavioral, and psychosocial levels, in a longitudinal study of preschool children. In January 2013, we launched the Helsinki Longitudinal SLI study (HelSLI) at the Helsinki University Hospital ( http://tiny.cc/HelSLI ). We will study 227 children aged 3-6 years with suspected DLD and their 160 typically developing peers. Five subprojects will determine how the child's psychological characteristics and environment correlate with DLD and how the child's well-being relates to DLD, the characteristics of DLD in monolingual versus bilingual children, nonlinguistic cognitive correlates of DLD, electrophysiological underpinnings of DLD, and the role of genetic risk factors. Methods include saliva samples, EEG, computerized cognitive tasks, neuropsychological and speech and language assessments, video-observations, and questionnaires. The project aims to increase our understanding of the multiple interactive risk and protective factors that affect the developing heterogeneous cognitive and behavioral profile of DLD, including factors affecting literacy development. This accumulated knowledge will form a heuristic basis for the development of new interventions targeting linguistic and non-linguistic aspects of DLD.

Parent and Child Cigarette Use: A Longitudinal, Multigenerational Study

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Staff, Jeremy

2013-01-01

OBJECTIVES: Using longitudinal data from the multigenerational Youth Development Study (YDS), this article documents how parents’ long-term smoking trajectories are associated with adolescent children’s likelihood of smoking. Prospective data from the parents (from age 14–38 years) enable unique comparisons of the parents’ and children’s smoking behavior, as well as that of siblings. METHODS: Smoking trajectories are constructed using latent class analysis for the original YDS cohort (n = 1010). Multigenerational longitudinal data from 214 parents and 314 offspring ages 11 years and older are then analyzed by using logistic regression with cluster-corrected SEs. RESULTS: Four latent smoking trajectories emerged among the original cohort: stable nonsmokers (54%), early-onset light smokers who quit/reduce (16%), late-onset persistent smokers (14%), and early-onset persistent heavy smokers (16%). Although 8% of children of stable nonsmokers smoked in the last year, the other groups’ children had much higher percentages, ranging from 23% to 29%. Multivariate logistic regression models confirm that these significant differences were robust to the inclusion of myriad child- and parent-level measures (for which child age and grade point average [GPA] are significant predictors). Older sibling smoking, however, mediated the link between parental heavy smoking and child smoking. CONCLUSIONS: Even in an era of declining rates of teenage cigarette use in the United States, children of current and former smokers face an elevated risk of smoking. Prevention efforts to weaken intergenerational associations should consider parents’ long-term cigarette use, as well as the smoking behavior of older siblings in the household. PMID:23918887

The Effects of CLIL on Oral Comprehension and Production: A Longitudinal Case Study

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Pérez Cañado, María Luisa; Lancaster, Nina Karen

2017-01-01

This article reports on the outcomes of a longitudinal case study to gauge the impact of content and language integrated learning (CLIL) on two of the least researched language skills: oral comprehension and production. It worked with 24 students in the fourth grade of Compulsory Secondary Education in a public school in Andalusia (southern Spain)…

DNA methylation age is associated with mortality in a longitudinal Danish twin study

DEFF Research Database (Denmark)

Christiansen, Lene; Lenart, Adam; Tan, Qihua

2016-01-01

included a 10-year longitudinal study of the 86 oldest-old twins (mean age of 86.1 at follow-up), which subsequently were followed for mortality for 8 years. We found that the DNAm age is highly correlated with chronological age across all age groups (r = 0.97), but that the rate of change of DNAm age...

Physical activity and asthma: A longitudinal and multi-country study.

Science.gov (United States)

Russell, Melissa A; Janson, Christer; Real, Francisco Gómez; Johannessen, Ane; Waatevik, Marie; Benediktsdóttir, Bryndis; Holm, Mathias; Lindberg, Eva; Schlünssen, Vivi; Raza, Wasif; Dharmage, Shyamali C; Svanes, Cecilie

2017-11-01

To investigate the impact of physical activity on asthma in middle-aged adults, in one longitudinal analysis, and one multi-centre cross-sectional analysis. The Respiratory Health in Northern Europe (RHINE) is a population-based postal questionnaire cohort study. Physical activity, height and weight were self-reported in Bergen, Norway, at RHINE II (1999-2001) and all centres at RHINE III (2010-2012). A longitudinal analysis of Bergen data investigated the association of baseline physical activity with follow-up asthma, incident asthma and symptoms, using logistic and zero-inflated Poisson regression (n = 1782). A cross-sectional analysis of all RHINE III centres investigated the association of physical activity with concurrent asthma and symptoms (n = 13,542) using mixed-effects models. Body mass index (BMI) was categorised (asthma (odds ratio [OR] 0.44, 95% confidence interval [CI] 0.22, 0.89), whilst an effect from undertaking vigorous activity 3+ times/week was not detected (OR 1.22, 95% CI 0.44, 2.76). The associations were attenuated with BMI adjustment. In the all-centre cross-sectional analysis an interaction was found, with the association between physical activity and asthma varying across BMI categories. These findings suggest potential longer-term benefit from lighter physical activity, whilst improvement in asthma outcomes from increasing activity intensity was not evident. Additionally, it appears the benefit from physical activity may differ according to BMI.

The Developmental Sequence of Social-Communicative Skills in Young Children with Autism: A Longitudinal Study

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Wu, Chin-Chin; Chiang, Chung-Hsin

2014-01-01

To explore the different developmental trajectories of social-communicative skills in children with autism and typically developing infants, two longitudinal studies were conducted. In Study 1, we examined the developmental sequence of social-communicative skills in 26 typically developing infants when they were 9 months old and reexamined them…

Emotional and Behavioural Problems in the Context of Cyberbullying: A Longitudinal Study among German Adolescents

Science.gov (United States)

Schultze-Krumbholz, Anja; Jakel, Anne; Schultze, Martin; Scheithauer, Herbert

2012-01-01

Although many studies have reported on internalising and externalising problems related to cyberbullying roles, there is a lack of longitudinal research in this area. This study reports (1) cross-sectional data from 412 German middle-school students to examine differences between cyberbullies, cybervictims and cyberbully-victims compared to…

Perceived maternal autonomy-support and early adolescent emotion regulation: a longitudinal study

OpenAIRE

Brenning, Katrijn; Soenens, Bart; Van Petegem, Stijn; Vansteenkiste, Maarten

2015-01-01

This study investigated longitudinal associations between perceived maternal autonomy-supportive parenting and early adolescents' use of three emotion regulation (ER) styles: emotional integration, suppressive regulation, and dysregulation. We tested whether perceived maternal autonomy support predicted changes in ER and whether these ER styles, in turn, related to changes in adjustment (i.e., depressive symptoms, self-esteem). Participants (N= 311, mean age at Time 1 = 12.04) reported on per...

Psychological Distress among Nursing, Physiotherapy and Occupational Therapy Students: A Longitudinal and Predictive Study

Science.gov (United States)

Nerdrum, Per; Rustoen, Tone; Helge Ronnestad, Michael

2009-01-01

In this study, we present longitudinal data on changes in psychological distress among 232 Norwegian undergraduate students of nursing, physiotherapy, and occupational therapy. Psychological distress was assessed by applying the 12-item version of the General Health Questionnaire. Nursing students became substantially more distressed during the…

Removed from the List: A Comparative Longitudinal Case Study of a Reconstitution-Eligible School.

Science.gov (United States)

Mac Iver, Douglas J.; Ruby, Allen; Balfanz, Robert; Byrnes, Vaughan

2002-01-01

Longitudinal case study of reform efforts centering on the Talent Development Middle School model at low-performing, high-poverty middle school in Philadelphia. Finds that student gains in mathematics, science, and reading achievement at subject school exceeded that of students in comparable school. (Contains 19 references.) (PKP)

Variable selection and estimation for longitudinal survey data

KAUST Repository

Wang, Li; Wang, Suojin; Wang, Guannan

2014-01-01

There is wide interest in studying longitudinal surveys where sample subjects are observed successively over time. Longitudinal surveys have been used in many areas today, for example, in the health and social sciences, to explore relationships

Habilidades cognitivas em indivíduos muito idosos: um estudo longitudinal Cognitive abilities in older seniors: a longitudinal study

Directory of Open Access Journals (Sweden)

Irani I. de Lima Argimon

2005-02-01

Full Text Available Estudos longitudinais com idosos com mais de oitenta anos são escassos na literatura. A pesquisa foi delineada com o objetivo de analisar as modificações no perfil de algumas habilidades cognitivas em indivíduos muito idosos, em dois momentos, com um intervalo de três anos. Pesquisa do tipo quantitativo, com delineamento longitudinal e prospectivo. A amostra, randômica, foi constituída por 66 indivíduos de 80 a 95 anos de idade na etapa I e, três anos após, na etapa II, por 46 idosos. Os instrumentos usados foram: Escala de Depressão Geriátrica, Questionário de Percepção Subjetiva de Queixas de Memória, Mini-Exame do Estado Mental, Span de Números, Teste de Lembranças Livres e com Pistas de Buschke, Teste de Fluência Verbal - Categoria Animal. Houve uma pequena tendência de decréscimo no desempenho cognitivo em um período de três anos. Maior número de atividades de lazer e mais anos de escolaridade foram fatores preditivos de menor variação no desempenho cognitivo. Apesar da idade avançada, os idosos apresentaram um desempenho de habilidades cognitivas cujo declínio foi de intensidade leve, não sendo suficiente para acarretar mudanças significativas no seu padrão cognitivo.Longitudinal studies of older seniors (over 80 years are rare in the literature. This research was designed to study cognitive abilities in the oldest old at two different moments with a three-year interval. The research was quantitative, with a longitudinal and prospective design. The sample consisted of 66 individuals from 80 to 95 years of age, randomly selected for phase I, with 46 of these individuals tested again three years later, in phase II. The instruments used were: Geriatric Depression Scale, Subjective Perception of Memory Problems, Mini-Mental State Examination, Digit Span, Buschke Test of Free and Cued Recall, and the Verbal Fluency Test - Animal Category. The results indicated that there was a small downward trend in the older

Longitudinal phase space characterization of the blow-out regime of rf photoinjector operation

Directory of Open Access Journals (Sweden)

J. T. Moody

2009-07-01

Full Text Available Using an experimental scheme based on a vertically deflecting rf deflector and a horizontally dispersing dipole, we characterize the longitudinal phase space of the beam in the blow-out regime at the UCLA Pegasus rf photoinjector. Because of the achievement of unprecedented resolution both in time (50 fs and energy (1.0 keV, we are able to demonstrate some important properties of the beams created in this regime such as extremely low longitudinal emittance, large temporal energy chirp, and the degrading effects of the cathode image charge in the longitudinal phase space which eventually leads to poorer beam quality. All of these results have been found in good agreement with simulations.

Longitudinal impedance and wake from XFEL undulators. Impact on current-enhanced SASE schemes

Energy Technology Data Exchange (ETDEWEB)

Geloni, G.; Saldin, E.; Schneidmiller, E.; Yurkov, M.

2007-06-15

In this article we derive longitudinal impedance and wake function for an undulator setup with arbitrary undulator parameter, taking into account a finite transverse size of the electron bunch. Earlier studies considered a line density-distribution of electrons instead. We focus our attention on the long-wavelength asymptote (compared with resonance wavelength), at large distance of the electron bunch from the undulator entrance compared to the overtaking length, and for large vacuumchamber size compared to the typical transverse size of the field. These restrictions define a parameter region of interest for practical applications. We calculate a closed expression for impedance and wake function that may be evaluated numerically in the most general case. Such expression allows us to derive an analytical solution for a Gaussian transverse and longitudinal bunch shape. Finally, we study the feasibility of current-enhanced SASE schemes (ESASE) recently proposed for LCLS, that fall well-within our approximations. Numerical estimations presented in this paper indicate that impedance-induced energy spread is sufficient to seriously degrade the FEL performance. Our conclusion is in contrast with results in literature, where wake calculations for the LCLS case are given in free-space, as if the presence of the undulator were negligible. (orig.)

Sleep problems and internet addiction among children and adolescents: a longitudinal study.

Science.gov (United States)

Chen, Yi-Lung; Gau, Susan Shur-Fen

2016-08-01

Although the literature has documented associations between sleep problems and internet addiction, the temporal direction of these relationships has not been established. The purpose of this study is to evaluate the bidirectional relationships between sleep problems and internet addiction among children and adolescents longitudinally. A four-wave longitudinal study was conducted with 1253 children and adolescents in grades 3, 5 and 8 from March 2013 to January 2014. The sleep problems of the student participants were measured by parental reports on the Sleep Habit Questionnaire, which catalogues early insomnia, middle insomnia, disturbed circadian rhythm, periodic leg movements, sleep terrors, sleepwalking, sleep talking, nightmares, bruxism, snoring and sleep apnoea. The severity of internet addiction was measured by students' self-reports on the Chen Internet Addiction Scale. Based on the results of time-lag models, dyssomnias (odds ratio = 1.31), especially early and middle insomnias (odds ratio = 1.74 and 2.24), sequentially predicted internet addiction, and internet addiction sequentially predicted disturbed circadian rhythm (odds ratio = 2.40), regardless of adjustment for gender and age. This is the first study to demonstrate the temporal relationship of early and middle insomnia predicting internet addiction, which subsequently predicts disturbed circadian rhythm. These findings imply that treatment strategies for sleep problems and internet addiction should vary according to the order of their occurrence. © 2016 European Sleep Research Society.

Hearing Impairment and Incident Dementia: Findings from the English Longitudinal Study of Ageing.

Science.gov (United States)

Davies, Hilary R; Cadar, Dorina; Herbert, Annie; Orrell, Martin; Steptoe, Andrew

2017-09-01

To determine whether hearing loss is associated with incident physician-diagnosed dementia in a representative sample. Retrospective cohort study. English Longitudinal Study of Ageing. Adults aged 50 and older. Cross-sectional associations between self-reported (n = 7,865) and objective hearing measures (n = 6,902) and dementia were examined using multinomial-logistic regression. The longitudinal association between self-reported hearing at Wave 2 (2004/05) and cumulative physician-diagnosed dementia up to Wave 7 (2014/15) was modelled using Cox proportional hazards regression. After adjustment for potential confounders, in cross-sectional analysis, participants who had self-reported or objective moderate and poor hearing were more likely to have a dementia diagnosis than those with normal hearing (self-reported: odds ratio OR = 1.6, 95% CI = 1.1-2.4 moderate hearing; OR = 2.6, 95% CI = 1.7-3.9 poor hearing, objective: OR = 1.6, 95% CI = 1.0-2.8 moderate hearing; OR = 4.4, 95% CI = 1.9-9.9 poor hearing). Longitudinally, the hazard of developing dementia was 1.4 (95% CI = 1.0-1.9) times as high in individuals who reported moderate hearing and 1.6 (95% CI = 1.1-2.0) times as high in those who reported poor hearing. Older adults with hearing loss are at greater risk of dementia than those with normal hearing. These findings are consistent with the rationale that correction of hearing loss could help delay the onset of dementia, or that hearing loss itself could serve as a risk indicator for cognitive decline. © 2017, The Authors. The Journal of the American Geriatrics Society published by Wiley Periodicals, Inc. on behalf of The American Geriatrics Society.

Optimal assignment methods in three-form planned missing data designs for longitudinal panel studies

NARCIS (Netherlands)

Jorgensen, T.D.; Rhemtulla, M.; Schoemann, A.; McPherson, B.; Wu, W.; Little, T.D.

2014-01-01

Planned missing designs are becoming increasingly popular, but because there is no consensus on how to implement them in longitudinal research, we simulated longitudinal data to distinguish between strategies of assigning items to forms and of assigning forms to participants across measurement

Migraine and subclinical atherosclerosis in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil).

Science.gov (United States)

Goulart, Alessandra C; Santos, Itamar S; Bittencourt, Márcio S; Lotufo, Paulo A; Benseñor, Isabela M

2016-08-01

The relationship between migraine and coronary heart disease (CHD) remains controversial. We aimed to investigate the association of subclinical atherosclerosis and migraine with or without aura compared to a non-migraine subgroup (reference) in a large Brazilian multicentric cohort study, the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil). Migraine diagnostic was based on International Headache Society criteria, and aura symptoms were validated by a medical doctor in a sub-sample of the ELSA-Brasil, who also underwent coronary artery calcium score (CAC) and carotid intima-media thickness (C-IMT) evaluations. Subclinical atherosclerosis indexes (CAC and C-IMT) were analyzed as dependent variables and migraine (all, with aura, without aura) as an independent variable in the linear and multinomial logistic regression models adjusted for possible confounders. Of 3217 ELSA participants free from CVD at baseline, we found a migraine frequency of 11.9% (5.1% with aura and 6.8% without aura). Overall, migraineurs were mostly women, younger and had lower frequency of CV risk factors, such as hypertension, diabetes and low HDL-cholesterol, compared to non-migraineurs. The strongest inverse correlation between migraine and subclinical atherosclerosis was verified with CAC score. However, all associations lost their significance after multivariate adjustment. In this cross-sectional evaluation of the ELSA study, migraine was not associated with subclinical atherosclerosis, regardless of aura symptoms. © International Headache Society 2015.

Emergence of the neural network underlying phonological processing from the prereading to the emergent reading stage: A longitudinal study.

Science.gov (United States)

Yu, Xi; Raney, Talia; Perdue, Meaghan V; Zuk, Jennifer; Ozernov-Palchik, Ola; Becker, Bryce L C; Raschle, Nora M; Gaab, Nadine

2018-05-01

Numerous studies have shown that phonological skills are critical for successful reading acquisition. However, how the brain network supporting phonological processing evolves and how it supports the initial course of learning to read is largely unknown. Here, for the first time, we characterized the emergence of the phonological network in 28 children over three stages (prereading, beginning reading, and emergent reading) longitudinally. Across these three time points, decreases in neural activation in the left inferior parietal cortex (LIPC) were observed during an audiovisual phonological processing task, suggesting a specialization process in response to reading instruction/experience. Furthermore, using the LIPC as the seed, a functional network consisting of the left inferior frontal, left posterior occipitotemporal, and right angular gyri was identified. The connection strength in this network co-developed with the growth of phonological skills. Moreover, children with above-average gains in phonological processing showed a significant developmental increase in connection strength in this network longitudinally, while children with below-average gains in phonological processing exhibited the opposite trajectory. Finally, the connection strength between the LIPC and the left posterior occipitotemporal cortex at the prereading level significantly predicted reading performance at the emergent reading stage. Our findings highlight the importance of the early emerging phonological network for reading development, providing direct evidence for the Interactive Specialization Theory and neurodevelopmental models of reading. © 2018 Wiley Periodicals, Inc.

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

Science.gov (United States)

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.

Development of numerical processing in children with typical and dyscalculic arithmetic skills – a longitudinal study

Directory of Open Access Journals (Sweden)

Karin eLanderl

2013-07-01

Full Text Available Numerical processing has been demonstrated to be closely associated with arithmetic skills, however, our knowledge on the development of the relevant cognitive mechanisms is limited. The present longitudinal study investigated the developmental trajectories of numerical processing in 42 children with age-adequate arithmetic development and 41 children with dyscalculia over a two-year period from beginning of Grade 2, when children were 7;6 years old, to beginning of Grade 4. A battery of numerical processing tasks (dot enumeration, non-symbolic and symbolic comparison of one- and two-digit numbers, physical comparison, number line estimation was given five times during the study (beginning and middle of each school year. Efficiency of numerical processing was a very good indicator of development in numerical processing while within-task effects remained largely constant and showed low long-term stability before middle of Grade 3. Children with dyscalculia showed less efficient numerical processing reflected in specifically prolonged response times. Importantly, they showed consistently larger slopes for dot enumeration in the subitizing range, an untypically large compatibility effect when processing two-digit numbers, and they were consistently less accurate in placing numbers on a number line. Thus, we were able to identify parameters that can be used in future research to characterize numerical processing in typical and dyscalculic development. These parameters can also be helpful for identification of children who struggle in their numerical development.

Effects of Team and Organizational Commitment--A Longitudinal Study

Science.gov (United States)

Neininger, Alexandra; Lehmann-Willenbrock, Nale; Kauffeld, Simone; Henschel, Angela

2010-01-01

Retention management, i.e., keeping qualified employees, is a top priority for contemporary organizations. Commitment, and especially team commitment, can be the key to mastering this challenge. There is a lack of longitudinal research concerning the development and the direction of the effects of team commitment over time. In a longitudinal…

Longitudinal study of spatial working memory development in young children.

Science.gov (United States)

Tsujii, Takeo; Yamamoto, Eriko; Masuda, Sayako; Watanabe, Shigeru

2009-05-27

This study longitudinally compared activity in the frontal cortex during a spatial working memory task between 5-year-old and 7-year-old children using near-infrared spectroscopy. Eight children participated in this study twice, once at 5 years and once at 7 years of age. Behavioral analysis showed that older children performed the working memory task more precisely and more rapidly than younger children. Near-infrared spectroscopy analysis showed that right hemisphere dominance was observed in older children, whereas no hemispheric difference was apparent in younger children. Children with strengthened lateralization showed improved performance from 5 to 7 years. We therefore offer the first demonstration of the developmental changes in frontal cortical activation during spatial working memory tasks during the preschool period.

Middle longitudinal fasciculus delineation within language pathways: A diffusion tensor imaging study in human

Energy Technology Data Exchange (ETDEWEB)

Menjot de Champfleur, Nicolas, E-mail: nicolasdechampfleur@orange.fr [Department of Neuroradiology, University Hospital Center, Gui de Chauliac Hospital, Montpellier (France); Team “Plasticity of Central Nervous System, Stem Cells and Glial Tumors,” Institut National de la Santé et de la Recherche Médicale Unité 1051, Institut of Neurosciences of Montpellier, Saint Eloi Hospital, Montpellier (France); Lima Maldonado, Igor [Department of Neuroradiology, University Hospital Center, Gui de Chauliac Hospital, Montpellier (France); Team “Plasticity of Central Nervous System, Stem Cells and Glial Tumors,” Institut National de la Santé et de la Recherche Médicale Unité 1051, Institut of Neurosciences of Montpellier, Saint Eloi Hospital, Montpellier (France); Divisão de Neurologia e Epidemiologia (CPPHO), Complexo Hospital Universitário Professor Edgard Santos, Universidade Federal da Bahia, Salvador-Bahia (Brazil); Moritz-Gasser, Sylvie [Department of Neuroradiology, University Hospital Center, Gui de Chauliac Hospital, Montpellier (France); Department of Neurology, University Hospital Center, Gui de Chauliac Hospital, Montpellier (France); Machi, Paolo [Department of Neuroradiology, University Hospital Center, Gui de Chauliac Hospital, Montpellier (France); and others

2013-01-15

Introduction: The existence in the human brain of the middle longitudinal fasciculus (MdLF), initially described in the macaque monkey, is supported by diffusion tensor imaging studies. In the present work, we aim (1) to confirm that this fascicle is found constantly in control subjects with the use of DTI techniques and (2) to delineate the MdLF from the other fiber bundles that constitute the language pathways. Materials and methods: Tractography was realized in four right-handed healthy volunteers for the arcuate fascicle, uncinate fascicle, inferior fronto-occipital fascicle, inferior longitudinal fascicle and the middle longitudinal fascicle. The fiber tracts were characterized for their size, mean fractional anisotropy (FA), for their length, number of streamlines, and lateralization indices were calculated. Results: The MdLF is found constantly and it is clearly delineated from the other fascicles that constitute the language pathways, especially the ventral pathway. It runs within the superior temporal gyrus white matter from the temporal pole, then it extends caudally in the upper part of the sagittal stratum and the posterior part of the corona radiata, to reach the inferior parietal lobule (angular gyrus). We found a leftward asymmetry for all fiber tracts when considering the mean FA. Discussion: Using DTI methods, we confirm that the MdLF connects the angular gyrus and the superior temporal gyrus. On the basis of these findings, the role of the MdLF is discussed. Conclusion: The middle longitudinal fasciculus, connects the angular gyrus and the superior temporal gyrus and its course can be systematically differenciated from those of other fascicles composing both ventral and dorsal routes (IFOF, IFL, AF and UF)

Middle longitudinal fasciculus delineation within language pathways: A diffusion tensor imaging study in human

International Nuclear Information System (INIS)

Menjot de Champfleur, Nicolas; Lima Maldonado, Igor; Moritz-Gasser, Sylvie; Machi, Paolo

2013-01-01

Introduction: The existence in the human brain of the middle longitudinal fasciculus (MdLF), initially described in the macaque monkey, is supported by diffusion tensor imaging studies. In the present work, we aim (1) to confirm that this fascicle is found constantly in control subjects with the use of DTI techniques and (2) to delineate the MdLF from the other fiber bundles that constitute the language pathways. Materials and methods: Tractography was realized in four right-handed healthy volunteers for the arcuate fascicle, uncinate fascicle, inferior fronto-occipital fascicle, inferior longitudinal fascicle and the middle longitudinal fascicle. The fiber tracts were characterized for their size, mean fractional anisotropy (FA), for their length, number of streamlines, and lateralization indices were calculated. Results: The MdLF is found constantly and it is clearly delineated from the other fascicles that constitute the language pathways, especially the ventral pathway. It runs within the superior temporal gyrus white matter from the temporal pole, then it extends caudally in the upper part of the sagittal stratum and the posterior part of the corona radiata, to reach the inferior parietal lobule (angular gyrus). We found a leftward asymmetry for all fiber tracts when considering the mean FA. Discussion: Using DTI methods, we confirm that the MdLF connects the angular gyrus and the superior temporal gyrus. On the basis of these findings, the role of the MdLF is discussed. Conclusion: The middle longitudinal fasciculus, connects the angular gyrus and the superior temporal gyrus and its course can be systematically differenciated from those of other fascicles composing both ventral and dorsal routes (IFOF, IFL, AF and UF)

A Comparative Study on Fatigue Life Optimization of the Intersection between a Longitudinal and a Webframe

DEFF Research Database (Denmark)

Birk-Sørensen, Martin

1996-01-01

to improve the design. A new improved slot for the longitudinal intersection in the web plate is found on the basis of a shape optimization of the conventional slot. The new slot has an unique shape (tongue form) resulting in a stress relaxation around the slot. Both the conventional and the new slot...... structure were analyzed by FEM followed by fatigue life calculations and subsequently compared. The overall expected fatigue life for the shape optimized slot will increase by approximately 12 %. The results were compared with an another study concerning a slot for a T-longitudinal....

Trust dynamics in a large system implementation

DEFF Research Database (Denmark)

Schlichter, Bjarne Rerup; Rose, Jeremy

2013-01-01

outcomes, but largely ignored the dynamics of trust relations. Giddens, as part of his study of modernity, theorises trust dynamics in relation to abstract social systems, though without focusing on information systems. We use Giddens’ concepts to investigate evolving trust relationships in a longitudinal......A large information systems implementation (such as Enterprise Resource Planning systems) relies on the trust of its stakeholders to succeed. Such projects impact diverse groups of stakeholders, each with their legitimate interests and expectations. Levels of stakeholder trust can be expected...... case analysis of a large Integrated Hospital System implementation for the Faroe Islands. Trust relationships suffered a serious breakdown, but the project was able to recover and meet its goals. We develop six theoretical propositions theorising the relationship between trust and project outcomes...

PHYSICAL PROPERTIES OF LARGE AND SMALL GRANULES IN SOLAR QUIET REGIONS

Energy Technology Data Exchange (ETDEWEB)

Yu Daren; Xie Zongxia; Hu Qinghua [Harbin Institute of Technology, Harbin 150001 (China); Yang Shuhong; Zhang Jun; Wang Jingxiu, E-mail: caddiexie@hotmail.com, E-mail: zjun@ourstar.bao.ac.cn [Key Laboratory of Solar Activity, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China)

2011-12-10

The normal mode observations of seven quiet regions obtained by the Hinode spacecraft are analyzed to study the physical properties of granules. An artificial intelligence technique is introduced to automatically find the spatial distribution of granules in feature spaces. In this work, we investigate the dependence of granular continuum intensity, mean Doppler velocity, and magnetic fields on granular diameter. We recognized 71,538 granules by an automatic segmentation technique and then extracted five properties: diameter, continuum intensity, Doppler velocity, and longitudinal and transverse magnetic flux density to describe the granules. To automatically explore the intrinsic structures of the granules in the five-dimensional parameter space, the X-means clustering algorithm and one-rule classifier are introduced to define the rules for classifying the granules. It is found that diameter is a dominating parameter in classifying the granules and two families of granules are derived: small granules with diameters smaller than 1.''44, and large granules with diameters larger than 1.''44. Based on statistical analysis of the detected granules, the following results are derived: (1) the averages of diameter, continuum intensity, and Doppler velocity in the upward direction of large granules are larger than those of small granules; (2) the averages of absolute longitudinal, transverse, and unsigned flux density of large granules are smaller than those of small granules; (3) for small granules, the average of continuum intensity increases with their diameters, while the averages of Doppler velocity, transverse, absolute longitudinal, and unsigned magnetic flux density decrease with their diameters. However, the mean properties of large granules are stable; (4) the intensity distributions of all granules and small granules do not satisfy Gaussian distribution, while that of large granules almost agrees with normal distribution with a peak at 1.04 I

Longitudinal Risk Factors for Cyberbullying in Adolescence

OpenAIRE

Sticca, Fabio; Ruggieri, Sabrina; Alsaker, Françoise; Perren, Sonja

2013-01-01

Cyberbullying has emerged as a new form of antisocial behaviour in the context of online communication over the last decade. The present study investigates potential longitudinal risk factors for cyberbullying. A total of 835 Swiss seventh graders participated in a short-term longitudinal study (two assessments 6 months apart). Students reported on the frequency of cyberbullying, traditional bullying, rule-breaking behaviour, cybervictimisation, traditional victimisation, and frequency of onl...

Individual changes in dental fear among children and parents: a longitudinal study.

Science.gov (United States)

Luoto, Anni; Tolvanen, Mimmi; Rantavuori, Kari; Pohjola, Vesa; Karlsson, Linnea; Lahti, Satu

2014-11-01

The aim was to study longitudinal changes in dental fear among children and one of their parents separately for girls, boys, mothers and fathers over a 3.5-year period. 11-12-year-old children in Pori, Finland (n = 1691) and one of their parents were invited to participate in this longitudinal study. Dental fear was measured in 2001, 2003 and 2005 when the children were 11-12, 13-14 and 15-16-years-old, respectively. The participants were asked if they were afraid of dental care (1 = 'not afraid', 2 = 'slightly afraid', 3 = 'afraid to some degree', 4 = 'quite afraid', 5 = 'very afraid' and 6 = 'I don't know'). The participants' gender was also registered. Mean values of the change scores were studied. Prevalence and incidence of dental fear and changes in dichotomized dental fear (responses 4-5 = high dental fear and responses 1-3 = low dental fear) were studied using cross-tabulations and Cochran's Q test. Overall, the prevalence of dental fear slightly increased and female preponderance in dental fear became more evident during the follow-up. Of the mothers and children with high dental fear at the baseline, 24% and 56%, respectively, reported not to be fearful at the end of the follow-up. Dental fear seems to be more stable in adulthood than in childhood. Thus, it might be better to intervene in dental fear during childhood rather than during adulthood.

Maternal patterns of postpartum alcohol consumption by age: A longitudinal analysis of adult urban mothers

OpenAIRE

Liu, Weiwei; Mumford, Elizabeth A.; Petras, Hanno

2015-01-01

The purpose of this study is to investigate a) longitudinal patterns of maternal postpartum alcohol use as well as its variation by maternal age at child birth; b) within maternal age groups, the association between other maternal characteristics and alcohol use patterns for the purposes of informed prevention design. Study sample consists of 3,397 mothers from the Fragile Families and Child Wellbeing Study representing medium and large U.S. urban areas. Maternal drinking and binge drinking w...

Need for longitudinal studies of Asian wildlife in the face of crises

Directory of Open Access Journals (Sweden)

Shermin de Silva

2016-04-01

Full Text Available Conservation biology is conceived as a discipline that must balance the short-term aim of gathering data on pressing conservation issues with the long-term vision of protecting populations, species, and functional ecosystems. Asian wildlife face imminent threats ranging from hunting to loss of critical habitats, but there are few examples of detailed longitudinal wildlife research in the region. Longitudinal research is essential for protecting populations especially in light of the high volumes of legal and illegal trade, understanding basic population dynamics, notably with respect to long-lived species, as well as accommodating the spatial needs of animals. It is also critical for evaluating the success of conservation or management interventions and adaptively improving outcomes. Such studies, particularly when requiring sustained field work, are impeded by mismatches between needs on the ground vs. the priorities of different stakeholders, the ephemeral and inefficient nature of funding mechanisms, and by the logistics of maintaining sites and personnel. Yet we cannot adequately protect biodiversity in Asia unless the magnitude of human impacts on its species is quantitatively understood and used to inform management.

Parenting characteristics and adolescent psychological well-being: a longitudinal study in a Chinese context.

Science.gov (United States)

Shek, D T

1999-02-01

In this longitudinal study, the relationships between perceived parenting characteristics and adolescent psychological well-being were examined in a sample of Hong Kong Chinese adolescents (N = 378). The results indicated that global parenting styles and specific parenting behaviors are concurrently related to hopelessness, life satisfaction, self-esteem, purpose in life, and general psychiatric morbidity at Time 1 and Time 2. Longitudinal and prospective analyses (Time 1 predictors of Time 2 criterion variables) suggested that the relations between parenting characteristics and adolescent psychological well-being are bidirectional in nature. The results indicated that the strengths of association between perceived parenting characteristics and adolescent psychological well-being are stronger in female than in male adolescents. Relative to maternal parenting characteristics, paternal parenting was found to exert a stronger influence on adolescent psychological well-being.

PSYCHOSEXUAL FUNCTIONING AFTER TREATMENT FOR CANCER OF THE CERVIX - A COMPARATIVE AND LONGITUDINAL-STUDY

NARCIS (Netherlands)

SCHULTZ, WCMW; VANDEWIEL, HBM; BOUMA, J

1991-01-01

Twenty-six couples participated in a 2-year longitudinal study of sexual functioning before and after treatment for carcinoma of the cervix. Sexual functioning was measured on admission prior to their treatment and at 6, 12 and 24 months follow-up and made operational in terms of current sexual

The Interpersonal Antecedents of Supportive Parenting: A Prospective, Longitudinal Study from Infancy to Adulthood

Science.gov (United States)

Raby, K. Lee; Lawler, Jamie M.; Shlafer, Rebecca J.; Hesemeyer, Paloma S.; Collins, W. Andrew; Sroufe, L. Alan

2015-01-01

This study drew on prospective, longitudinal data to test the hypothesis that the intergenerational transmission of positive parenting is mediated by competence in subsequent relationships with peers and romantic partners. Interview-based ratings of supportive parenting were completed with a sample of 113 individuals (46% male) followed from birth…

Video-Based Interaction, Negotiation for Comprehensibility, and Second Language Speech Learning: A Longitudinal Study

Science.gov (United States)

Saito, Kazuya; Akiyama, Yuka

2017-01-01

This study examined the impact of video-based conversational interaction on the longitudinal development (one academic semester) of second language production by college-level Japanese English-as-a-foreign-language learners. Students in the experimental group engaged in weekly dyadic conversation exchanges with native speakers in the United States…

Longitudinal genetic study of verbal and nonverbal IQ from early childhood to young adulthood.

NARCIS (Netherlands)

Hoekstra, R.A.; Bartels, M.; Boomsma, D.I.

2007-01-01

In a longitudinal genetic study we explored which factors underlie stability in verbal and nonverbal abilities, and the extent to which the association between these abilities becomes stronger as children grow older. Measures of verbal and nonverbal IQ were collected in Dutch twin pairs at age 5, 7,

Functional ability and oral health among older people: a longitudinal study from age 75 to 80

DEFF Research Database (Denmark)

Avlund, K; Holm-Pedersen, P; Schroll, M

2001-01-01

: The study included a random sample of 75-year-olds at baseline and a follow-up study 5 years later. The data are treated as two cross-sectional studies at age 75 and 80, respectively, and as a longitudinal study from age 75 to 80. SETTING: The western part of Copenhagen County. PARTICIPANTS: The two cross......-sectional studies of 75- and 80-year-old people included 411 and 321 persons, respectively. The longitudinal study from age 75 to 80 included the 326 persons who participated in both surveys. MEASUREMENTS: Oral health status was measured roughly by number of teeth and chewing ability. Use of dental services...... diseases, self-rated health, socio-demographic factors, living alone, and social relations were included as possible confounders. RESULTS: The odds ratio of having no or few teeth was 1.7 (1.1-2.6) in 75-year-old individuals who felt tired in mobility, 1.7 (1.0-2.9) in 80-year-old persons who needed help...

Physical activity levels and determinants of change in young adults: a longitudinal panel study

OpenAIRE

Zimmermann Erwin; Wanner Miriam; Zimmermann-Sloutskis Dorith; Martin Brian W

2010-01-01

Abstract Background There is growing concern about physical inactivity in adolescents and young adults. Identifying determinants that are associated with low levels of physical activity and with changes in physical activity levels will help to develop specific prevention strategies. The present study describes the prevalence and potential determinants of physical activity behavior and behavior changes of young adults. The study is based on the Swiss Household Panel (SHP), a longitudinal study...

Longitudinal changes in cortical thickness in autism and typical development.

Science.gov (United States)

Zielinski, Brandon A; Prigge, Molly B D; Nielsen, Jared A; Froehlich, Alyson L; Abildskov, Tracy J; Anderson, Jeffrey S; Fletcher, P Thomas; Zygmunt, Kristen M; Travers, Brittany G; Lange, Nicholas; Alexander, Andrew L; Bigler, Erin D; Lainhart, Janet E

2014-06-01

The natural history of brain growth in autism spectrum disorders remains unclear. Cross-sectional studies have identified regional abnormalities in brain volume and cortical thickness in autism, although substantial discrepancies have been reported. Preliminary longitudinal studies using two time points and small samples have identified specific regional differences in cortical thickness in the disorder. To clarify age-related trajectories of cortical development, we examined longitudinal changes in cortical thickness within a large mixed cross-sectional and longitudinal sample of autistic subjects and age- and gender-matched typically developing controls. Three hundred and forty-five magnetic resonance imaging scans were examined from 97 males with autism (mean age = 16.8 years; range 3-36 years) and 60 males with typical development (mean age = 18 years; range 4-39 years), with an average interscan interval of 2.6 years. FreeSurfer image analysis software was used to parcellate the cortex into 34 regions of interest per hemisphere and to calculate mean cortical thickness for each region. Longitudinal linear mixed effects models were used to further characterize these findings and identify regions with between-group differences in longitudinal age-related trajectories. Using mean age at time of first scan as a reference (15 years), differences were observed in bilateral inferior frontal gyrus, pars opercularis and pars triangularis, right caudal middle frontal and left rostral middle frontal regions, and left frontal pole. However, group differences in cortical thickness varied by developmental stage, and were influenced by IQ. Differences in age-related trajectories emerged in bilateral parietal and occipital regions (postcentral gyrus, cuneus, lingual gyrus, pericalcarine cortex), left frontal regions (pars opercularis, rostral middle frontal and frontal pole), left supramarginal gyrus, and right transverse temporal gyrus, superior parietal lobule, and

Longitudinal categorical data analysis

CERN Document Server

Sutradhar, Brajendra C

2014-01-01

This is the first book in longitudinal categorical data analysis with parametric correlation models developed based on dynamic relationships among repeated categorical responses. This book is a natural generalization of the longitudinal binary data analysis to the multinomial data setup with more than two categories. Thus, unlike the existing books on cross-sectional categorical data analysis using log linear models, this book uses multinomial probability models both in cross-sectional and longitudinal setups. A theoretical foundation is provided for the analysis of univariate multinomial responses, by developing models systematically for the cases with no covariates as well as categorical covariates, both in cross-sectional and longitudinal setups. In the longitudinal setup, both stationary and non-stationary covariates are considered. These models have also been extended to the bivariate multinomial setup along with suitable covariates. For the inferences, the book uses the generalized quasi-likelihood as w...

Seasonal variation of strongylosis in working donkeys of Ethiopia: a cross-sectional and longitudinal studies.

Science.gov (United States)

Dibaba, Motuma Debelo; Getachew, A M; Assefa, Zerihun; Fanta, Alemayehu; Etana, Manyahilishal; Firew, Seyoum; Goshu, Lemessa; Burden, F

2017-07-01

Helminths are one of the major health problems of working donkeys, often with heavy worm burden and contributing to their early demise and/or reduction in their work output. Cross-sectional and longitudinal studies were conducted to investigate the current infection prevalence and level of strongyles infection donkeys would acquire through different seasons in the mid-lowland agro-ecological zones of Ethiopia. For this purpose, faecal samples from 206 (cross-sectional study) and 102 (longitudinal study) randomly selected donkeys were directly collected from the rectum and analysed. For the longitudinal study, the 102 donkeys dewormed at the end of main rainy season, beginning of October, were monitored for the level of strongyle infection they would acquire during subsequent dry and short rainy seasons. The cross-sectional study of 206 donkey has revealed an overall infection prevalence of 89.3% (95% confidence interval (CI) = 84.4, 92.9). Donkeys in the lowland zone showed a significantly higher strongyle infection prevalence (P = 0.0126) and mean eggs per gramme of faces (EPG) (P = 0.001; 2775 EPG) compared to donkeys in the midland zone (980.8 EPG). Age, sex and body condition did not have any significant effect on either the infection prevalence or level of infection (P > 0.05). The longitudinal study has shown a significantly lower strongyle infection prevalence (P = 0.003) and level of infection donkeys acquired (P = 0.001) in the subsequent dry and short rainy seasons compared to the main rainy season following October deworming. However, these values were not significantly different between the two agro-ecological zones (P > 0.05). This study clearly showed that parasitic infections are primarily acquired during the main rainy season when pasture/herbage coverage is relatively better, and the environment is conducive for parasites survival and development. On the other hand, the finding of majority of donkeys shedding low or no eggs during the

Longitudinal magnetoresistance and magnototermopower in Bi nanowires

International Nuclear Information System (INIS)

Para, G.

2011-01-01

Full text: The galvanomagnetic effect of single crystals Bi nanowires have been studied in longitudinal magnetic fields up to 14 T. The influence of diameters, temperature and deformation extension on the longitudinal magnetoresistance and magnetotermopower (H||I, H||ΔT) of bismuth nanowires is studied. Elastic deformation measurements were conducted at maximum relative elongation 2 %. For the first time have been investigated the magnetotermopower of Bi nanowires with d=45 nm. Essentially non monotonic dependence H max on temperature in longitudinal thermopower in wires with d=45-60 nm is found out. Such difference in behavior of maximum on R(H) and on α(H) in wires with d<100nm says that the behavior of resistance is caused by other mechanism, then thermopower. (author)

Longitudinal study of extended-spectrum-β-lactamase- and AmpC-Producing Enterobacteriaceae in household dogs

NARCIS (Netherlands)

Baede, V.O.; Wagenaar, J.A.; Broens, E.M.; Duim, Birgitta; Dohmen, Wietske; Nijsse, Rolf; Timmerman, Arjen J.; Hordijk, Joost

2015-01-01

A longitudinal study was performed to (i) investigate the continuity of shedding of extended-spectrum-beta-lactamase (ESBL)-producing Enterobacteriaceae in dogs without clinical signs, (ii) identify dominant plasmid-mediated ESBL genes, and (iii) quantify ESBL-producing Enterobacteriaceae in

Comprehensive Longitudinal Study Challenges the Existence of Neonatal Imitation in Humans.

Science.gov (United States)

Oostenbroek, Janine; Suddendorf, Thomas; Nielsen, Mark; Redshaw, Jonathan; Kennedy-Costantini, Siobhan; Davis, Jacqueline; Clark, Sally; Slaughter, Virginia

2016-05-23

Human children copy others' actions with high fidelity, supporting early cultural learning and assisting in the development and maintenance of behavioral traditions [1]. Imitation has long been assumed to occur from birth [2-4], with influential theories (e.g., [5-7]) placing an innate imitation module at the foundation of social cognition (potentially underpinned by a mirror neuron system [8, 9]). Yet, the very phenomenon of neonatal imitation has remained controversial. Empirical support is mixed and interpretations are varied [10-16], potentially because previous investigations have relied heavily on cross-sectional designs with relatively small samples and with limited controls [17, 18]. Here, we report surprising results from the most comprehensive longitudinal study of neonatal imitation to date. We presented infants (n = 106) with nine social and two non-social models and scored their responses at 1, 3, 6, and 9 weeks of age. Longitudinal analyses indicated that the infants did not imitate any of the models, as they were just as likely to produce the gestures in response to control models as they were to matching models. Previous positive findings were replicated in limited cross-sections of the data, but the overall analyses confirmed these findings to be mere artifacts of restricted comparison conditions. Our results undermine the idea of an innate imitation module and suggest that earlier studies reporting neonatal imitation were methodologically limited. Copyright © 2016 Elsevier Ltd. All rights reserved.

Child incarceration and long-term adult health outcomes: a longitudinal study.

Science.gov (United States)

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.

Longitudinal phase space characterization of the blow-out regime of rf photoinjector operation

OpenAIRE

J. T. Moody; P. Musumeci; M. S. Gutierrez; J. B. Rosenzweig; C. M. Scoby

2009-01-01

Using an experimental scheme based on a vertically deflecting rf deflector and a horizontally dispersing dipole, we characterize the longitudinal phase space of the beam in the blow-out regime at the UCLA Pegasus rf photoinjector. Because of the achievement of unprecedented resolution both in time (50 fs) and energy (1.0 keV), we are able to demonstrate some important properties of the beams created in this regime such as extremely low longitudinal emittance, large temporal energy chirp, and ...

Quantifying sources of bias in longitudinal data linkage studies of child abuse and neglect: measuring impact of outcome specification, linkage error, and partial cohort follow-up.

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Parrish, Jared W; Shanahan, Meghan E; Schnitzer, Patricia G; Lanier, Paul; Daniels, Julie L; Marshall, Stephen W

2017-12-01

Health informatics projects combining statewide birth populations with child welfare records have emerged as a valuable approach to conducting longitudinal research of child maltreatment. The potential bias resulting from linkage misspecification, partial cohort follow-up, and outcome misclassification in these studies has been largely unexplored. This study integrated epidemiological survey and novel administrative data sources to establish the Alaska Longitudinal Child Abuse and Neglect Linkage (ALCANLink) project. Using these data we evaluated and quantified the impact of non-linkage misspecification and single source maltreatment ascertainment use on reported maltreatment risk and effect estimates. The ALCANLink project integrates the 2009-2011 Alaska Pregnancy Risk Assessment Monitoring System (PRAMS) sample with multiple administrative databases through 2014, including one novel administrative source to track out-of-state emigration. For this project we limited our analysis to the 2009 PRAMS sample. We report on the impact of linkage quality, cohort follow-up, and multisource outcome ascertainment on the incidence proportion of reported maltreatment before age 6 and hazard ratios of selected characteristics that are often available in birth cohort linkage studies of maltreatment. Failure to account for out-of-state emigration biased the incidence proportion by 12% (from 28.3% w to 25.2% w ), and the hazard ratio (HR) by as much as 33% for some risk factors. Overly restrictive linkage parameters biased the incidence proportion downwards by 43% and the HR by as much as 27% for some factors. Multi-source linkages, on the other hand, were of little benefit for improving reported maltreatment ascertainment. Using the ALCANLink data which included a novel administrative data source, we were able to observe and quantify bias to both the incidence proportion and HR in a birth cohort linkage study of reported child maltreatment. Failure to account for out

Academic and Work-Related Burnout: A Longitudinal Study of Working Undergraduate University Business Students

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Galbraith, Craig S.; Merrill, Gregory B.

2012-01-01

We examined the interaction between academic burnout and work-related burnout for a sample of working undergraduate university students. Using a longitudinal design we found that the factors of burnout (Exhaustion, Cynicism, and Efficacy) change significantly over the semester. In addition, the study suggests there are distinct differences in how…

Changing Stereotypes, Changing Grades: A Longitudinal Study of Stereotyping during a College Math Course

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Ramsey, Laura R.; Sekaquaptewa, Denise

2011-01-01

Previous research has illuminated an important connection between stereotypes and the performance of those targeted by a stereotype. This body of work suggests that even implicit (i.e., nonconscious and unintended) math-gender stereotyping is related to poor math performance among women. Our longitudinal study sought to measure students'…

Prevalence, Incidence, and Resolution of Nocturnal Polyuria in a Longitudinal Community-based Study in Older Men : The Krimpen Study

NARCIS (Netherlands)

van Doorn, Boris; Blanker, Marco H.; Kok, Esther T.; Westers, Paul; Bosch, J. L. H. Ruud

Background: Nocturnal polyuria (NP) is common in older men and can lead to nocturia. However, no longitudinal data are available on the natural history of NP. Objective: To determine prevalence, incidence, and resolution rates of NP. Design, setting, and participants: A longitudinal, community-based

Deviant Peer Affiliation as an Explanatory Mechanism in the Association between Corporal Punishment and Physical Aggression: a Longitudinal Study among Chinese Adolescents.

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Zhu, Jianjun; Yu, Chengfu; Bao, Zhenzhou; Jiang, Yanping; Zhang, Wei; Chen, Yuanyuan; Qiu, Boyu; Zhang, Jianjun

2017-11-01

Previous research has focused primarily on corporal punishment as a cause and adolescents' physical aggression as an outcome. However, there is a large gap in knowledge of the potentially bidirectional association and explanatory mechanism underlying the association between corporal punishment and physical aggression. The current study, using a longitudinal design across three time points (the fall semester of 7th grade, the fall of 8th grade, and the fall of 9th grade), aimed to a) examine the reciprocal processes between corporal punishment and physical aggression, and b) explore whether deviant peer affiliation may explain such reciprocal connections. Only adolescents participating in all the three time points were included in this study, resulting in a final sample of 342 adolescents (175 boys, 167 girls) who completed questionnaires regarding corporal punishment, deviant peer affiliation, and aggression. Gender, age and socioeconomic status were controlled for in the analyses. Autoregressive cross-lagged models showed that the results did not support the direct reciprocal effect between corporal punishment and physical aggression among Chinese adolescents. A direct longitudinal link from corporal punishment to physical aggression was found, however, the inverse association was not significant. Moreover, regarding the longitudinal underlying process, in one direction, corporal punishment at 7th grade predicted higher levels of deviant peer affiliation at 8th grade. In turn, higher deviant peer affiliation at 8th grade predicted increased physical aggression at 9th grade. At the same time, in the other direction, adolescent physical aggression at 7th grade significantly predicted deviant peer affiliation at 8th grade. In turn, higher deviant peer affiliation at 8th grade predicted decreased corporal punishment at 9th grade. Identifying the direct and underlying reciprocal processes between corporal punishment and adolescent physical aggression has important

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

Science.gov (United States)

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

Terapia de linguagem de irmãos com transtornos invasivos do desenvolvimento: estudo longitudinal Language therapy of brothers with pervasive developmental disorders: longitudinal study

Directory of Open Access Journals (Sweden)

Andréa Regina Nunes Misquiatti

2010-01-01

Full Text Available O objetivo deste trabalho foi descrever o processo de intervenção fonoaudiológica de dois irmãos com transtornos invasivos do desenvolvimento, por meio de um estudo longitudinal de caso clínico. Participaram dois irmãos, um de nove e outro de 11 anos de idade, ambos do gênero masculino, com autismo (Caso 1 e transtorno invasivo do desenvolvimento sem outra especificação (Caso 2. Como procedimento de coleta e análise de dados foi realizado um estudo longitudinal, por meio de acompanhamento dos casos ao longo de quatro anos de intervenção fonoaudiológica. Foram realizadas filmagens durante as sessões de terapia, análise documental de informações dos prontuários referentes à anamnese, avaliação e relatórios terapêuticos fonoaudiológicos, exames e avaliações multidisciplinares. Em ambos os casos houve melhora no contato visual, na interação social, no vocabulário e na brincadeira simbólica. No Caso 1 ocorreu aumento de 2,0 para 6,2 atos comunicativos por minuto, no Caso 2 de 3,5 para 8,0 atos e ambos demonstraram predominância do meio verbal e maior variedade de funções comunicativas. Outros fatores influenciaram estes resultados, como a deficiência intelectual, a dinâmica familiar, os conflitos no relacionamento entre os irmãos e o ambiente escolar em que estavam inseridos. Confirmou-se a relevância do fonoaudiólogo em intervenções nos transtornos invasivos do desenvolvimento, junto a equipes multidisciplinares, para a discussão diagnóstica e de condutas mais adequadas. Estudos longitudinais podem contribuir para uma análise mais detalhada e fidedigna de intervenções terapêuticas nesses casos, para esclarecer lacunas existentes na literatura e subsidiar a atuação do fonoaudiólogo clínico.The aim of this research was to describe the language intervention process of two brothers with pervasive developmental disorders, through a longitudinal clinical case study. Two brothers - one nine and the other 11

Persistent work-life conflict and health satisfaction - a representative longitudinal study in Switzerland

OpenAIRE

Knecht, Michaela; Bauer, Georg F; Gutzwiller, Felix; Hämmig, Oliver

2011-01-01

Abstract Background The objectives of the present study were (1) to track work-life conflict in Switzerland during the years 2002 to 2008 and (2) to analyse the relationship between work-life conflict and health satisfaction, examining whether long-term work-life conflict leads to poor health satisfaction. Methods The study is based on a representative longitudinal database (Swiss Household Panel), covering a six-year period containing seven waves of data collection. The sample includes 1261 ...

Neuropathologic Studies of the Baltimore Longitudinal Study of Aging (BLSA)

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O’Brien, Richard J.; Resnick, Susan M.; Zonderman, Alan B.; Ferrucci, Luigi; Crain, Barbara J.; Pletnikova, Olga; Rudow, Gay; Iacono, Diego; Riudavets, Miguel A.; Driscoll, Ira; Price, Donald L.; Martin, Lee J.; Troncoso, Juan C.

2010-01-01

The Baltimore Longitudinal Study of Aging (BLSA) was established in 1958 and is one the oldest prospective studies of aging in the USA and the world. The BLSA is supported by the National Institute of Aging (NIA) and its mission is to learn what happens to people as they get old and how to sort out changes due to aging and from those due to disease or other causes. In 1986, an autopsy program combined with comprehensive neurologic and cognitive evaluations was established in collaboration with the Johns Hopkins University Alzheimer’s Disease Research Center (ADRC). Since then, 211 subjects have undergone autopsy. Here we review the key clinical neuropathological correlations from this autopsy series. The focus is on the morphological and biochemical changes that occur in normal aging, and the early neuropathological changes of neurodegenerative diseases, especially Alzheimer’s disease (AD). We highlight the combined clinical, pathologic, morphometric, and biochemical evidence of asymptomatic AD, a state characterized by normal clinical evaluations in subjects with abundant AD pathology. We conclude that in some individuals, successful cognitive aging results from compensatory mechanisms that occur at the neuronal level (i.e., neuronal hypertrophy and synaptic plasticity) whereas a failure of compensation may culminate in disease. PMID:19661626

Longitudinal plasma metabolic profiles, infant feeding, and islet autoimmunity in the MIDIA study.

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Jørgenrud, Benedicte; Stene, Lars C; Tapia, German; Bøås, Håkon; Pepaj, Milaim; Berg, Jens P; Thorsby, Per M; Orešič, Matej; Hyötyläinen, Tuulia; Rønningen, Kjersti S

2017-03-01

The aim of this study was to investigate the longitudinal plasma metabolic profiles in healthy infants and the potential association with breastfeeding duration and islet autoantibodies predictive of type 1 diabetes. Up to four longitudinal plasma samples from age 3 months from case children who developed islet autoimmunity (n = 29) and autoantibody-negative control children (n = 29) with the HLA DR4-DQ8/DR3-DQ2 genotype were analyzed using two-dimensional gas chromatography coupled to a time-of-flight mass spectrometer for detection of small polar metabolites. Plasma metabolite levels were found to depend strongly on age, with fold changes varying up to 50% from age 3 to 24 months (p polar metabolites changed with age during early childhood, independent of later islet autoimmunity status and sex. Breastfeeding was associated with higher levels of branched-chain amino acids, and lower levels of methionine and 3,4-dihydroxybutyric acid. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Self-stigma and suicidality: a longitudinal study.

Science.gov (United States)

Oexle, Nathalie; Rüsch, Nicolas; Viering, Sandra; Wyss, Christine; Seifritz, Erich; Xu, Ziyan; Kawohl, Wolfram

2017-06-01

Mental illness stigma is a source of distress for persons with mental illness. Self-stigma occurs when negative stereotypes are internalized, leading to low self-esteem, shame and hopelessness. Due to its consequences self-stigma may contribute to suicidality and be a modifiable target for suicide prevention. Based on 222 disability pensioners with mental illness we examined whether self-stigma at baseline is associated with suicidal ideation over a 2-year period, controlling for baseline suicidal ideation, symptoms, age and gender. More self-stigma predicted suicidal ideation at baseline and longitudinally. Interventions on different levels to reduce self-stigma could improve suicide prevention.

Predicting Family Poverty and Other Disadvantaged Conditions for Child Rearing from Childhood Aggression and Social Withdrawal: A 30-Year Longitudinal Study

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Serbin, Lisa A.; Temcheff, Caroline E.; Cooperman, Jessica M.; Stack, Dale M.; Ledingham, Jane; Schwartzman, Alex E.

2011-01-01

This 30-year longitudinal study examined pathways from problematic childhood behavior patterns to future disadvantaged conditions for family environment and child rearing in adulthood. Participants were mothers (n = 328) and fathers (n = 222) with lower income backgrounds participating in the ongoing Concordia Longitudinal Risk Project. Structural…

Bipolar mood state reflected in cortico-amygdala resting state connectivity: A cohort and longitudinal study.

Science.gov (United States)

Brady, Roscoe O; Margolis, Allison; Masters, Grace A; Keshavan, Matcheri; Öngür, Dost

2017-08-01

Using resting-state functional magnetic resonance imaging (rsfMRI), we previously compared cohorts of bipolar I subjects in a manic state to those in a euthymic state to identify mood state-specific patterns of cortico-amygdala connectivity. Our results suggested that mania is reflected in the disruption of emotion regulation circuits. We sought to replicate this finding in a group of subjects with bipolar disorder imaged longitudinally across states of mania and euthymia METHODS: We divided our subjects into three groups: 26 subjects imaged in a manic state, 21 subjects imaged in a euthymic state, and 10 subjects imaged longitudinally across both mood states. We measured differences in amygdala connectivity between the mania and euthymia cohorts. We then used these regions of altered connectivity to examine connectivity in the longitudinal bipolar group using a within-subjects design. Our findings in the mania vs euthymia cohort comparison were replicated in the longitudinal analysis. Bipolar mania was differentiated from euthymia by decreased connectivity between the amygdala and pre-genual anterior cingulate cortex. Mania was also characterized by increased connectivity between amygdala and the supplemental motor area, a region normally anti-correlated to the amygdala in emotion regulation tasks. Stringent controls for movement effects limited the number of subjects in the longitudinal sample. In this first report of rsfMRI conducted longitudinally across mood states, we find that previously observed between-group differences in amygdala connectivity are also found longitudinally within subjects. These results suggest resting state cortico-amygdala connectivity is a biomarker of mood state in bipolar disorder. Copyright © 2017 Elsevier B.V. All rights reserved.

Longitudinal research and data collection in primary care.

Science.gov (United States)

van Weel, Chris

2005-01-01

This article reviews examples of and experience with longitudinal research in family medicine. The objective is to use this empirical information to formulate recommendations for improving longitudinal research. The article discusses 3 longitudinal studies from the Nijmegen academic family practice research network: 1 on the prognosis of depression and 1 each on the prognosis of and outcomes of care for type 2 diabetes mellitus. The Nijmegen network has recorded all episodes of morbidity encountered in Dutch family medicine since 1971 in a stable practice population. This network's experience is evaluated to identify lessons that may help other practice-based research networks (PBRNs) in pursuing longitudinal research. In terms of external conditions (conditions related to the general setting), the stability of a population and a high level of continuity of care substantially enhance the ability to perform longitudinal research. In terms of internal conditions (conditions related to the PBRN), motivation of family physicians and their staff to conduct ongoing data collection, and their ownership of the data are key for success. Other critical internal conditions include standardization of data; collection of data by clinician-friendly means; training of family physicians and their staff in data collection, as well as meetings for discussion of this task; provision of feedback to practices on the research findings; use of standard procedures to promote adherence to data collection; availability of facilities for regular measurement of patients' health status or chart review; and use of mechanisms for tracking patients who leave the practice area. Insight from existing experience suggests that longitudinal research can be enhanced in PBRNs. The best way forward is to build longitudinal data collection by drawing on lessons from successful studies. Primary care research policy should advocate for a role of longitudinal research and stimulate its development in PBRNs

New fatherhood and psychological distress: a longitudinal study of Australian men.

Science.gov (United States)

Leach, Liana S; Olesen, Sarah C; Butterworth, Peter; Poyser, Carmel

2014-09-15

Despite growing interest and concern about men's mental health during the perinatal period, we still do not know whether men are more vulnerable to mental health problems during this time. The current study is one of the first to use longitudinal, population-based data to investigate whether becoming an expectant and/or new father is associated with increases in psychological distress. We analyzed 10 waves of data collected annually (from 2001 to 2010) from the nationally representative Household, Income, and Labour Dynamics in Australia (HILDA) Survey. Over this time, 349 men were identified as new fathers (first child aged fatherhood. Longitudinal mixed models showed no significant increase in psychological distress as a function of expectant or new fatherhood; instead, some improvement in mental health was observed. The finding suggests that expectant and new fathers are not at greater risk of poor mental health. Future epidemiologic research should continue to identify those men who are most (and least) at risk during the perinatal period in order to target resources and assistance most effectively. © The Author 2014. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Large-scale structural alteration of brain in epileptic children with SCN1A mutation

Directory of Open Access Journals (Sweden)

Yun-Jeong Lee

2017-01-01

Significance: This study showed large-scale developmental brain changes in patients with epilepsy and SCN1A gene mutation, which may be associated with the core symptoms of the patients. Further longitudinal MRI studies with larger cohorts are required to confirm the effect of SCN1A gene mutation on structural brain development.

Nutritional status and quality of life of cancer patients needing exclusive chemotherapy: a longitudinal study.

Science.gov (United States)

Salas, Sebastien; Mercier, Sophie; Moheng, Benjamin; Olivet, Sandrine; Garcia, Marie-Eve; Hamon, Sophie; Sibertin-Blanc, Camille; Duffaud, Florence; Auquier, Pascal; Baumstarck, Karine

2017-04-27

The aims of this study were to report nutritional status in a large panel of patients with cancer requiring exclusive chemotherapy and to study the influence of nutritional status on their quality of life (QoL). This work was a longitudinal cohort study performed at a French university teaching hospital. Eligible patients were individuals with a cancer needing treatment based on exclusive chemotherapy. Three work-ups were performed: i) before the administration of the first course of chemotherapy: T1, ii) before the administration of the second (for patients with 3 planned courses) or third (patients with 6 planned courses) course: T2, and iii) before the administration of the last planned course: T3. The following data were collected: general health (performance status) and nutritional status (weight, anorexia grading, albuminemia, pre-albuminemia, and C-reactive protein) and QoL. The nutritional status of patients with cancer was preserved. Functional impairment, the presence of anorexia, the palliative nature of the chemotherapy, and an elevated C-reactive protein dosage were independent predictive factors of a lower QoL among patients assessed at the end of chemotherapy. Although larger studies should corroborate these findings, clinicians may include this information in the management of patients with cancer requiring exclusive chemotherapy to identify the most vulnerable patients. Current controlled trials NCT01687335 (registration date: October 6, 2011).

Dorsal longitudinal foreskin cut is associated with reduced risk of HIV, syphilis and genital herpes in men: a cross-sectional study in Papua New Guinea.

Science.gov (United States)

Vallely, Andrew J; MacLaren, David; David, Matthew; Toliman, Pamela; Kelly-Hanku, Angela; Toto, Ben; Tommbe, Rachael; Kombati, Zure; Kaima, Petronia; Browne, Kelwyn; Manineng, Clement; Simeon, Lalen; Ryan, Claire; Wand, Handan; Hill, Peter; Law, Greg; Siba, Peter M; McBride, W John H; Kaldor, John M

2017-04-03

Various forms of penile foreskin cutting are practised in Papua New Guinea. In the context of an ecological association observed between HIV infection and the dorsal longitudinal foreskin cut, we undertook an investigation of this relationship at the individual level. We conducted a cross-sectional study among men attending voluntary confidential HIV counselling and testing clinics. Following informed consent, participants had a face-to-face interview and an examination to categorize foreskin status. HIV testing was conducted on site and relevant specimens collected for laboratory-based Herpes simplex type-2 (HSV-2), syphilis, Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG), and Trichomonas vaginalis (TV) testing. Overall, 1073 men were enrolled: 646 (60.2%) were uncut; 339 (31.6%) had a full dorsal longitudinal cut; 72 (6.7%) a partial dorsal longitudinal cut; and 14 (1.3%) were circumcised. Overall, the prevalence of HIV was 12.3%; HSV-2, 33.6%; active syphilis, 12.1%; CT, 13.4%; NG, 14.1%; and TV 7.6%. Compared with uncut men, men with a full dorsal longitudinal cut were significantly less likely to have HIV (adjusted odds ratio [adjOR] 0.25, 95%CI: 0.12, 0.51); HSV-2 (adjOR 0.60, 95%CI: 0.41, 0.87); or active syphilis (adjOR 0.55, 95%CI: 0.31, 0.96). This apparent protective effect was restricted to men cut prior to sexual debut. There was no difference between cut and uncut men for CT, NG or TV. In this large cross-sectional study, men with a dorsal longitudinal foreskin cut were significantly less likely to have HIV, HSV-2 and syphilis compared with uncut men, despite still having a complete (albeit morphologically altered) foreskin. The protective effect of the dorsal cut suggests that the mechanism by which male circumcision works is not simply due to the removal of the inner foreskin and its more easily accessible HIV target cells. Exposure of the penile glans and inner foreskin appear to be key mechanisms by which male circumcision confers

Generation of longitudinally polarized terahertz pulses with field amplitudes exceeding 2 kV/cm