WorldWideScience

Sample records for larger longitudinal studies

  1. Is Parental Involvement Lower at Larger Schools?

    Science.gov (United States)

    Walsh, Patrick

    2010-01-01

    Parents who volunteer, or who lobby for improvements in school quality, are generally seen as providing a school-wide public good. If so, straightforward public-good theory predicts that free-riding will reduce average involvement at larger schools. This study uses longitudinal data to follow families over time, as their children move from middle…

  2. SME routes for innovation collaboration with larger enterprises

    DEFF Research Database (Denmark)

    Brink, Tove

    2017-01-01

    The research in this paper reveals how Small and Medium-sized Enterprises (SMEs) can contribute to industry competiveness through collaboration with larger enterprises. The research is based on a longitudinal qualitative case study starting in 2011 with 10 SME offshore wind farm suppliers...... and follow-up interviews in 2013. The research continued with a second approach in 2014 within operation and maintenance (O&M) through focus group interviews and subsequent individual interviews with 20 enterprises and a seminar in May 2015. The findings reveal opportunities and challenges for SMEs according...... to three different routes for cooperation and collaboration with larger enterprises: demand-driven cooperation, supplier-driven cooperation and partnerdriven collaboration. The SME contribution to innovation and competiveness is different within the three routes and ranges from providing specific knowledge...

  3. Longitudinal changes and seasonal variations in serum 25-hydroxyvitamin D levels in different age groups: results of the Longitudinal Aging Study Amsterdam

    NARCIS (Netherlands)

    van Schoor, N. M.; Knol, D. L.; Deeg, D. J. H.; Peters, F. P. A. M. N.; Heijboer, A. C.; Lips, P.

    2014-01-01

    Vitamin D levels remained fairly stable during ageing with increasing levels in persons aged 55-65 years old and decreasing levels in persons aged 65-88 years old. The seasonal variation was larger than the longitudinal change. Our findings implicate that vitamin D supplementation becomes more

  4. A study of the HEB longitudinal dynamics

    International Nuclear Information System (INIS)

    Larson, D.J.

    1993-12-01

    A study of the High Energy Booster (HEB) longitudinal dynamics is presented. Full derivations of ramp dependent longitudinal variables are given. The formulas assume that the input magnetic field and beam longitudinal emittance are known as a function of time, and that either the rf voltage or the rf bucket area are known as a function of time. Once these three inputs are specified, the formulas can be used to calculate values for all other longitudinal dynamics variables. The formulas have been incorporated into a single computer code named ELVIRA: Evaluation of Longitudinal Variables in Relativistic Accelerators. The ELVIRA code is documented here in detail. The ELVIRA code is used under two initial longitudinal emittance assumptions to plot ramp functions for the longitudinal dynamics design of the HEB as of May 5, 1992

  5. Sample size determination for mediation analysis of longitudinal data.

    Science.gov (United States)

    Pan, Haitao; Liu, Suyu; Miao, Danmin; Yuan, Ying

    2018-03-27

    Sample size planning for longitudinal data is crucial when designing mediation studies because sufficient statistical power is not only required in grant applications and peer-reviewed publications, but is essential to reliable research results. However, sample size determination is not straightforward for mediation analysis of longitudinal design. To facilitate planning the sample size for longitudinal mediation studies with a multilevel mediation model, this article provides the sample size required to achieve 80% power by simulations under various sizes of the mediation effect, within-subject correlations and numbers of repeated measures. The sample size calculation is based on three commonly used mediation tests: Sobel's method, distribution of product method and the bootstrap method. Among the three methods of testing the mediation effects, Sobel's method required the largest sample size to achieve 80% power. Bootstrapping and the distribution of the product method performed similarly and were more powerful than Sobel's method, as reflected by the relatively smaller sample sizes. For all three methods, the sample size required to achieve 80% power depended on the value of the ICC (i.e., within-subject correlation). A larger value of ICC typically required a larger sample size to achieve 80% power. Simulation results also illustrated the advantage of the longitudinal study design. The sample size tables for most encountered scenarios in practice have also been published for convenient use. Extensive simulations study showed that the distribution of the product method and bootstrapping method have superior performance to the Sobel's method, but the product method was recommended to use in practice in terms of less computation time load compared to the bootstrapping method. A R package has been developed for the product method of sample size determination in mediation longitudinal study design.

  6. A longitudinal study

    OpenAIRE

    Kristen, Astrid

    2010-01-01

    Does playing violent video games increase aggressive behavior over time or is it aggressive children who increasingly seek out (and play) these violent video games? To study such long-term effects a longitudinal design is necessary. Within a field study in a large German city (Kinder, Computer, Hobby, Lernen – KUHL, Freie Universtität Berlin) about 115 elementary school boys attending in the beginning (t1) classrooms of the third and fourth grade and twelve months later (t2) classrooms of the...

  7. Larger men have larger prostates: Detection bias in epidemiologic studies of obesity and prostate cancer risk.

    Science.gov (United States)

    Rundle, Andrew; Wang, Yun; Sadasivan, Sudha; Chitale, Dhananjay A; Gupta, Nilesh S; Tang, Deliang; Rybicki, Benjamin A

    2017-06-01

    Obesity is associated with risk of aggressive prostate cancer (PCa), but not with over-all PCa risk. However, obese men have larger prostates which may lower biopsy accuracy and cause a systematic bias toward the null in epidemiologic studies of over-all risk. Within a cohort of 6692 men followed-up after a biopsy or transurethral resection of the prostate (TURP) with benign findings, a nested case-control study was conducted of 495 prostate cancer cases and controls matched on age, race, follow-up duration, biopsy versus TURP, and procedure date. Data on body mass index and prostate volume at the time of the initial procedure were abstracted from medical records. Prior to consideration of differences in prostate volume, overweight (OR = 1.41; 95%CI 1.01, 1.97), and obese status (OR = 1.59; 95%CI 1.09, 2.33) at the time of the original benign biopsy or TURP were associated with PCa incidence during follow-up. Prostate volume did not significantly moderate the association between body-size and PCa, however it did act as an inverse confounder; adjustment for prostate volume increased the effect size for overweight by 22% (adjusted OR = 1.52; 95%CI 1.08, 2.14) and for obese status by 23% (adjusted OR = 1.77; 95%CI 1.20, 2.62). Larger prostate volume at the time of the original benign biopsy or TURP was inversely associated with PCa incidence during follow-up (OR = 0.92 per 10 cc difference in volume; 95%CI 0.88, 0.97). In analyses that stratified case-control pairs by tumor aggressiveness of the case, prostate volume acted as an inverse confounder in analyses of non-aggressive PCa but not in analyses of aggressive PCa. In studies of obesity and PCa, differences in prostate volume cause a bias toward the null, particularly in analyses of non-aggressive PCa. A pervasive underestimation of the association between obesity and overall PCa risk may exist in the literature. © 2017 Wiley Periodicals, Inc.

  8. 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.

  9. 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)

  10. Antiferromagnetic Ising model with transverse and longitudinal field

    International Nuclear Information System (INIS)

    Kischinhevsky, M.

    1985-01-01

    We study the quantum hamiltonian version of the Ising Model in one spacial dimension under an external longitudinal (uniform) field at zero temperature. A phenomenological renormalization group procedure is used to obtain the phase diagram; the transverse and longitudinal zero field limits are studied and we verify the validity of universality at non zero transverse fields, where two-dimensional critical behaviour is obtained. To perform the numerical calculations we use the Lanczos scheme, which gives highly precise results with rather short processing times. We also analyse the possibility of using these techniques to extend the present work to the quantum hamiltonian version of the q-state Potts Model (q>2) in larger system. (author) [pt

  11. A longitudinal study of the relationships between the Big Five personality traits and body size perception.

    Science.gov (United States)

    Hartmann, Christina; Siegrist, Michael

    2015-06-01

    The present study investigated the longitudinal development of body size perception in relation to different personality traits. A sample of Swiss adults (N=2905, 47% men), randomly selected from the telephone book, completed a questionnaire on two consecutive years (2012, 2013). Body size perception was assessed with the Contour Drawing Rating Scale and personality traits were assessed with a short version of the Big Five Inventory. Longitudinal analysis of change indicated that men and women scoring higher on conscientiousness perceived themselves as thinner one year later. In contrast, women scoring higher on neuroticism perceived their body size as larger one year later. No significant effect was observed for men scoring higher on neuroticism. These results were independent of weight changes, body mass index, age, and education. Our findings suggest that personality traits contribute to body size perception among adults. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. 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…

  13. Longitudinal morphometric MRI study of Alzheimer's disease

    International Nuclear Information System (INIS)

    Ogomori, Koji; Takano, Koichi; Kuwabara, Yasuo; Nakano, Seigo; Nawata, Hideyuki; Yano, Rika; Nishimura, Ryoji; Takita, Masashi

    2009-01-01

    A longitudinal morphometric MRI study of Alzheimer's disease (AD) was conducted to determine the relationship between the progression of the symptoms and the progression of the brain atrophy. The Voxel-based Specific Regional Analysis System for Alzheimer's Disease (VSRAD), developed by Matsuda et al. was used as a method of morphometry to perform the statistical MR image analysis. Thirty-eight patients of AD patients were investigated with VSRAD. These patients were divided into two groups according to the progression of symptoms based on a clinical evaluation. One group was the progress group (20 patients), while the other group was the stable group (18 patients) for comparison. The relationship was investigated between the speed of the symptomatic progression and the change in each VSRAD indicator. Consequently, the entorhinal Z-score and the entorhinal atrophy rate showed a correlation with the speed of the symptomatic progression. The increase of the entorhinal Z-score in the follow-up was larger in the progress group than that in the stable group (0.65/1.28 years in the progress group and 0.05/1.26 years in the stable group.). These results suggest that a rapid symptomatic progression in an AD patient accompanies the rapid progression of atrophy in the entorhinal cortex. (author)

  14. 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

  15. 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

  16. 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

  17. Sequential Progressions in a Theory of Mind Scale: Longitudinal Perspectives

    Science.gov (United States)

    Wellman, Henry M.; Fuxi, Fang; Peterson, Candida C.

    2011-01-01

    Consecutive re-testings of 92 U.S. preschoolers (n = 30), Chinese preschoolers (n = 31), and deaf children (n = 31) examined whether the sequences of development apparent in cross-sectional results with a theory-of-mind scale also appeared in longitudinal assessment. Longitudinal data confirmed that theory-of-mind progressions apparent in cross-sectional scaling data also characterized longitudinal sequences of understanding for individual children. The match between cross-sectional and longitudinal sequences appeared for children who exhibit different progressions across cultures (U.S. vs. China) and for children with substantial delays (deaf children of hearing parents). Moreover, greater scale distances reflected larger longitudinal age differences. PMID:21428982

  18. 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),…

  19. Excision and Patch Grafting of a Lateral Peyronie's Plaque—Utilizing a Longitudinal “Window” Approach

    Directory of Open Access Journals (Sweden)

    Kathy Lue, BS

    2015-06-01

    Conclusion: A lateral longitudinal incision for PIEG is a feasible technique and may reduce the postoperative morbidity and dissection required with traditional circumcising incision with penile degloving. Larger comparative studies are necessary for further evaluation. Lue K, Emtage JB, Martinez DR, Yang C, and Carrion R. Excision and patch grafting of a lateral Peyronie's plaque—Utilizing a longitudinal “window” approach. Sex Med 2015;3:86–89.

  20. Longitudinal development of muons in large air showers studies from the arrival time distributions measured at 900m above sea level

    Science.gov (United States)

    Kakimoto, F.; Tsuchimoto, I.; Enoki, T.; Suga, K.; Nishi, K.

    1985-01-01

    The arrival time distributions of muons with energies above 1.0GeV and 0.5GeV have been measured in the Akeno air-shower array to study the longitudinal development of muons in air showers with primary energies in the range 10 to the 17th power to 10 to the 18th power ev. The average rise times of muons with energies above 1.0GeV at large core distances are consistent with those expected from very high multiplicity models and, on the contrary, with those expected from the low multiplicity models at small core distances. This implies that the longitudinal development at atmospheric depth smaller than 500 cm square is very fast and that at larger atmospheric depths is rather slow.

  1. Red blood cells open promising avenues for longitudinal studies of ageing in laboratory, non-model and wild animals.

    Science.gov (United States)

    Stier, Antoine; Reichert, Sophie; Criscuolo, Francois; Bize, Pierre

    2015-11-01

    Ageing is characterized by a progressive deterioration of multiple physiological and molecular pathways, which impair organismal performance and increase risks of death with advancing age. Hence, ageing studies must identify physiological and molecular pathways that show signs of age-related deterioration, and test their association with the risk of death and longevity. This approach necessitates longitudinal sampling of the same individuals, and therefore requires a minimally invasive sampling technique that provides access to the larger spectrum of physiological and molecular pathways that are putatively associated with ageing. The present paper underlines the interest in using red blood cells (RBCs) as a promising target for longitudinal studies of ageing in vertebrates. RBCs provide valuable information on the following six pathways: cell maintenance and turnover (RBC number, size, and heterogeneity), glucose homeostasis (RBC glycated haemoglobin), oxidative stress parameters, membrane composition and integrity, mitochondrial functioning, and telomere dynamics. The last two pathways are specific to RBCs of non-mammalian species, which possess a nucleus and functional mitochondria. We present the current knowledge about RBCs and age-dependent changes in these pathways in non-model and wild species that are especially suitable to address questions related to ageing using longitudinal studies. We discuss how the different pathways relate with survival and lifespan and give information on their genetic and environmental determinants to appraise their evolutionary potential. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. A longitudinal study of the correlates of persistent smoking among sexual minority women.

    Science.gov (United States)

    Matthews, Alicia K; Riley, Barth B; Everett, Bethany; Hughes, Tonda L; Aranda, Frances; Johnson, Timothy

    2014-09-01

    We conducted a longitudinal evaluation of factors associated with persistent smoking behaviors among sexual minority women (SMW; lesbians and bisexual women). Structured interview data were collected as part of a larger longitudinal study of SMW's health: the Chicago Health and Life Experiences of Women study. We conducted multivariate analyses to evaluate the influence of 4 groups of predictor variables on smoking: (a) demographic, (b) childhood victimization, (c) other substance use, and (d) health variables. At Wave 1, 30.9% (n = 138) of participants reported current smoking, with substance-use and demographic factors having the strongest relationships to smoking status. The majority (84.9%) of Wave 1 smokers were also smoking at Wave 2. Among demographic variables, level of education was inversely associated with continued smoking. With respect to substance use, hazardous drinking and cocaine/heroin use were significantly associated with continued smoking. None of the victimization or health variables predicted smoking status. Consistent with previous studies, smoking rates in this sample of SMW were elevated. Despite intensive efforts to reduce smoking in the general population, 84% of SMW smokers continued smoking from Wave 1 to Wave 2. Findings suggest that the majority of SMW will continue to smoke over time. Additional research is needed to increase motivation and access to smoking cessation resources. © The Author 2014. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  3. NUMERICAL STUDY OF THE LONGITUDINALLY ASYMMETRIC DISTRIBUTION OF SOLAR ENERGETIC PARTICLES IN THE HELIOSPHERE

    Energy Technology Data Exchange (ETDEWEB)

    He, H.-Q.; Wan, W., E-mail: hqhe@mail.iggcas.ac.cn, E-mail: wanw@mail.iggcas.ac.cn [Key Laboratory of Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029 (China)

    2015-06-22

    Solar energetic particles (SEPs) affect the solar–terrestrial space environment and are very important to space weather research. In this work, we numerically investigate the transport processes of SEPs in the three-dimensional interplanetary magnetic field, with an emphasis on the longitudinal distribution of SEPs in the heliosphere. We confirm our previous finding that there exists an east–west longitudinal asymmetry in the SEP intensities, i.e., with the same longitude separations between the solar source centers and the magnetic footpoint of the observer, the fluxes of SEP events originating from solar sources located on the eastern side of the nominal magnetic footpoint of the observer are systematically larger than those of the SEP events originating from sources located on the western side. We discuss the formation mechanism of this phenomenon, and conclude that the longitudinally asymmetric distribution of SEPs results from the east–west azimuthal asymmetry in the topology of the heliospheric magnetic field as well as the effects of perpendicular diffusion on the transport of SEPs in the heliosphere. Our results will be valuable to understanding Sun–Earth relations and useful for space weather forecasting.

  4. 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.

  5. 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

  6. 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....

  7. 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.

  8. 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

  9. 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

  10. Longitudinal Patterns of Employment and Postsecondary Education for Adults with Autism and Average-Range IQ

    Science.gov (United States)

    Taylor, Julie Lounds; Henninger, Natalie A.; Mailick, Marsha R.

    2015-01-01

    This study examined correlates of participation in postsecondary education and employment over 12?years for 73 adults with autism spectrum disorders and average-range IQ whose families were part of a larger, longitudinal study. Correlates included demographic (sex, maternal education, paternal education), behavioral (activities of daily living,…

  11. 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…

  12. 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

  13. 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…

  14. A LONGITUDINAL ANALYSIS OF PARENTING PRACTICES, COUPLE SATISFACTION, AND CHILD BEHAVIOR PROBLEMS

    OpenAIRE

    Linville, Deanna; Chronister, Krista; Dishion, Tom; Todahl, Jeff; Miller, John; Shaw, Daniel; Gardner, Francis; Wilson, Melvin

    2010-01-01

    This longitudinal study examined the relationship between couple relationship satisfaction, parenting practices, parent depression, and child problem behaviors. The study participants (n = 148) were part of a larger experimental study that examined the effectiveness of a brief family-centered intervention, the Family Check-Up model. Regression analysis results indicated that our proposed model accounted for 38% of the variance in child problem behavior at Time 2, with child problem behavior a...

  15. Childhood predictors of adult adiposity: findings from a longitudinal study.

    Science.gov (United States)

    McLeod, Geraldine Fh; Fergusson, David M; Horwood, L John; Boden, Joseph M; Carter, Frances A

    2018-03-23

    The increasing prevalence of overweight and obesity has become a key challenge for New Zealand. The purpose of the present study was to examine childhood risk factors for adult adiposity in a longitudinal birth cohort. Data were gathered from the Christchurch Health and Development Study (CHDS), a birth cohort of 1,265 children born in Christchurch in 1977. Associations were examined between socio-demographic background, perinatal factors, infant and child characteristics, family functioning/child maltreatment and adiposity at ages 30 and 35 years. Adiposity was assessed using body mass index scores. At ages 30 and 35, approximately one-third of cohort members were overweight and one-fifth were obese. Generalised estimating equation models showed that statistically significant (p<.05) predictors of later adiposity and overweight/obesity were: male gender, being born into a single-parent family, having parents with larger body size, higher early infant growth, limited or no breastfeeding, lower levels of cognitive ability and exposure to severe sexual abuse. Overweight and obesity was associated with social and family background, biological endowment, cognitive ability and childhood adversity factors. These findings may assist in the development of structured adiposity intervention programmes in conjunction with established community organisations specialising in child and family health.

  16. 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

  17. The ρ-meson longitudinal leading-twist distribution amplitude

    Directory of Open Access Journals (Sweden)

    Hai-Bing Fu

    2014-11-01

    Full Text Available In the present paper, we suggest a convenient model for the vector ρ-meson longitudinal leading-twist distribution amplitude ϕ2;ρ‖, whose distribution is controlled by a single parameter B2;ρ‖. By choosing proper chiral current in the correlator, we obtain new light-cone sum rules (LCSR for the B→ρ TFFs A1, A2 and V, in which the δ1-order ϕ2;ρ‖ provides dominant contributions. Then we make a detailed discussion on the ϕ2;ρ‖ properties via those B→ρ TFFs. A proper choice of B2;ρ‖ can make all the TFFs agree with the lattice QCD predictions. A prediction of |Vub| has also been presented by using the extrapolated TFFs, which indicates that a larger B2;ρ‖ leads to a larger |Vub|. To compare with the BABAR data on |Vub|, the longitudinal leading-twist DA ϕ2;ρ‖ prefers a doubly-humped behavior.

  18. Longitudinal assessment of grey matter contraction in amyotrophic lateral sclerosis: A tensor based morphometry study.

    Science.gov (United States)

    Agosta, Federica; Gorno-Tempini, Maria Luisa; Pagani, Elisabetta; Sala, Stefania; Caputo, Domenico; Perini, Michele; Bartolomei, Ilaria; Fruguglietti, Maria Elena; Filippi, Massimo

    2009-06-01

    Our objective was to investigate grey matter (GM) contraction in patients with amyotrophic lateral sclerosis (ALS) using tensor based morphometry (TBM). Using a 1.5 Tesla scanner, T1-weighted MRI scans were obtained at baseline and at follow-up (mean interval, 9 months) from 16 ALS and 10 controls. Standard TBM procedures in Statistical Parametric Mapping (SPM2) were used for image processing and statistical analyses. The frontotemporal cortex and basal ganglia were considered areas of interest, based on pathological studies. Eight patients showed rapid clinical progression of ALS during the follow-up period. Compared to controls, all ALS patients showed progression of GM atrophy in left premotor cortex and right basal ganglia. Patients with rapidly progressing ALS showed GM atrophy changes in a larger motor cortical-subcortical area and in extramotor frontal regions compared to both controls and to non-rapidly progressing cases. Thus, TBM detected longitudinal atrophy changes in the motor network in ALS occurring over less than one year. The faster the clinical progression, the greater was the GM loss in motor and prefrontal areas. Further advances in tracking longitudinal changes in cortical and subcortical regions in ALS may provide an objective marker for monitoring disease progression, and the disease-modifying effect of potential treatments.

  19. 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.

  20. 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.

  1. 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.

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

    Science.gov (United States)

    Goldring, Shayla; Newman, Jim

    2010-01-01

    This issue of Population Trends includes a number of articles and reports resulting from research based on the ONS Longitudinal Study (ONS LS). They have been drawn together in one issue to highlight the value of this type of study for demographic research.2009 marked the 35th anniversary of the establishment of the ONS LS. The study now contains data from the last four censuses (1971 to 2001), linked to vital events data since 1971, for a sample of one per cent of the population of England and Wales.More recently, sister studies have been established in Scotland and Northern Ireland. The Scottish Longitudinal Study (SLS) started with 1991 Census data and the Northern Ireland Longitudinal Study (NILS)started with 2001 Census data.The lead article in this issue comes from an exemplar project that was established to explore how to utilise the three studies to carry out UK-wide longitudinal analysis. Two different methods were used to analyse socio-economic and country level differences in health and mortality across the studies. The article summarises the results of this analysis, reports on the relative strengths of the different methods used, and draws attention to a number of new resources that have been developed by the project researchers as aids to using all three studies.This is an excellent example of collaborative working across the UK, involving researchers from the Centre for Longitudinal Study Information and User Support (CeLSIUS) at the London School of Hygiene and Tropical Medicine, the Longitudinal Studies Centre - Scotland (LSCS) at the University of St.Andrews and the Northern Ireland Longitudinal Study - Research Support Unit (NILS-RSU) at Queen's University Belfast. The project also involved collaboration between ONS, the General Register Office for Scotland (GROS) and the Northern Ireland Statistics and Research Agency (NISRA) to ensure the secure transfer and handling of data from the three studies so that it could be brought together in one

  3. Feasibility study on longitudinal phase-space measurements at GSI UNILAC using charged-particle detectors

    Energy Technology Data Exchange (ETDEWEB)

    Milosic, Timo

    2014-04-14

    , introducing necessary concepts such as the phase space and emittance and is followed by a discussion of the data acquisition and data analysis. An important part of the latter is the introduction of a robust estimator for the covariance matrix of the measured distribution which is directly connected to the RMS emittance. However, the classical estimator is very sensitive to outliers in the measured data. The usual approach of subjective selection of cut regions is thereby avoided. The TOF setup has been tested with low and high current beams where a general sensitivity to the longitudinal phase-space distribution was confirmed. Furthermore, the gas pressure at the stripper section and the setup of the high-current slits, required for beam attenuation, have an impact on the measured distributions. Scattering of ions at the slits leads to a larger energy spread, larger bunch length and, consequently, emittance. Independent of the configuration, deviations from the expected values of the energy spread ΔE/ left angle E right angle ∼1 % and the Twiss parameter α∼4 have been measured. The energy spreads were larger than the theory values by a factor of 1.5-1.6. However, a direct measurement of the bunch structure, while using sensible high-current slit settings, proved valuable. Low-current measurements with the MC diamond detector featured a gain loss of 5 % pulse height and 2 % pulse integral after irradiation with ∼3 x 10{sup 4} argon ions. Although this effect is corrected in the data analysis, the energy spread is significantly larger than expected, like in the TOF measurements. Similarly, the values for α were below 0.5. Prominent trails in the measured distribution showed a broad energy spectrum and could be quantitatively attributed to interaction with the collimator apertures. As the measurements hint an insufficient energy resolution, this effect has been investigated in a Gaussian model space. The discrepancies between expected and measured values ΔE/ left

  4. Falls and fear of falling predict future falls and related injuries in ambulatory individuals with spinal cord injury: a longitudinal observational study

    Directory of Open Access Journals (Sweden)

    Vivien Jørgensen

    2017-04-01

    Conclusion: Ambulatory individuals have a high risk of falling and of fall-related injuries. Fall history, fear of falling and walking speed could predict recurrent falls and injurious falls. Further studies with larger samples are needed to validate these findings. [Jørgensen V, Butler Forslund E, Opheim A, Franzén E, Wahman K, Hultling C, Seiger Å, Ståhle A, Stanghelle JK, Roaldsen KS (2017 Falls and fear of falling predict future falls and related injuries in ambulatory individuals with spinal cord injury: a longitudinal observational study. Journal of Physiotherapy 63: 108–113

  5. 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

  6. 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

  7. Longitudinal study of fingerprint recognition.

    Science.gov (United States)

    Yoon, Soweon; Jain, Anil K

    2015-07-14

    Human identification by fingerprints is based on the fundamental premise that ridge patterns from distinct fingers are different (uniqueness) and a fingerprint pattern does not change over time (persistence). Although the uniqueness of fingerprints has been investigated by developing statistical models to estimate the probability of error in comparing two random samples of fingerprints, the persistence of fingerprints has remained a general belief based on only a few case studies. In this study, fingerprint match (similarity) scores are analyzed by multilevel statistical models with covariates such as time interval between two fingerprints in comparison, subject's age, and fingerprint image quality. Longitudinal fingerprint records of 15,597 subjects are sampled from an operational fingerprint database such that each individual has at least five 10-print records over a minimum time span of 5 y. In regard to the persistence of fingerprints, the longitudinal analysis on a single (right index) finger demonstrates that (i) genuine match scores tend to significantly decrease when time interval between two fingerprints in comparison increases, whereas the change in impostor match scores is negligible; and (ii) fingerprint recognition accuracy at operational settings, nevertheless, tends to be stable as the time interval increases up to 12 y, the maximum time span in the dataset. However, the uncertainty of temporal stability of fingerprint recognition accuracy becomes substantially large if either of the two fingerprints being compared is of poor quality. The conclusions drawn from 10-finger fusion analysis coincide with the conclusions from single-finger analysis.

  8. 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…

  9. 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

  10. 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.

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

    Science.gov (United States)

    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.

  12. 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…

  13. 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.

  14. 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

  15. 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…

  16. A Three-Year Longitudinal Study of Reading and Spelling Difficulty in Chinese Developmental Dyslexia: The Matter of Morphological Awareness.

    Science.gov (United States)

    Tong, Xiuhong; McBride, Catherine; Lo, Jason Chor Ming; Shu, Hua

    2017-11-01

    In the present study, we used a three-time point longitudinal design to investigate the associations of morphological awareness to word reading and spelling in a small group of those with and without dyslexia taken from a larger sample of 164 Hong Kong Chinese children who remained in a longitudinal study across ages 6, 7 and 8. Among those 164 children, 15 had been diagnosed as having dyslexia by professional psychologists, and 15 other children manifested average reading ability and had been randomly selected from the sample for comparison. All children were administered a battery of tasks including Chinese character recognition, word dictation, morphological awareness, phonological awareness and rapid automatized naming. Multivariate analysis of variance and predictive discriminate analysis were performed to examine whether the dyslexic children showed differences in the cognitive-linguistic tasks in comparison with controls. Results suggested that the dyslexic groups had poorer performance in morphological awareness and RAN across all 3 years. However, phonological awareness was not stable in distinguishing the groups. Findings suggest that morphological awareness is a relatively strong correlate of spelling difficulties in Chinese, but phonological awareness is not. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  17. 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

  18. A longitudinal study of altered taste and smell perception and change in blood pressure.

    Science.gov (United States)

    Liu, Y-H; Huang, Z; Vaidya, A; Li, J; Curhan, G C; Wu, S; Gao, X

    2018-05-29

    Previous studies suggest that olfactory receptors, which mediate smell chemosensation, are located in the kidney and involved in blood pressure regulation. Mammalian epithelial sodium channels located in taste receptor cells are also found to participate in blood pressure regulation. However, there is currently no human study that has examined the association between taste and smell function and blood pressure. We thus conducted a longitudinal study to examine whether participants with altered taste and smell perception had larger increases in blood pressure compared with those without altered perception in a community-based cohort. The study included 5190 Chinese adults (4058 men and 1132 women) who were normotensive at baseline. Taste and smell perception were assessed via questionnaire in 2012 (baseline). Blood pressure was measured in 2012 and 2014 to determine relative change in blood pressure. Mean differences of 2-year blood pressure change and 95% confidence intervals (CIs) across four categories of taste and smell perception were calculated after adjusting for known risk factors for hypertension. After adjusting for potential confounders, individuals with altered taste and smell perception had larger increases in systolic blood pressure (adjusted mean difference = 5.1 mmHg, 95% CI: 0.1-10.0, p-value: 0.04) and mean arterial pressure (adjusted mean difference = 3.8 mmHg, 95% CI: 0.4-7.1, p-value: 0.03) after two years of follow-up compared with those having neither altered taste nor altered smell perception. No significant association was observed in individuals with altered taste or smell perception only. Our results suggest an association between chemosensory function and blood pressure. Copyright © 2018 The Italian Society of Diabetology, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition, and the Department of Clinical Medicine and Surgery, Federico II University. Published by Elsevier B.V. All rights

  19. [Information management in multicenter studies: the Brazilian longitudinal study for adult health].

    Science.gov (United States)

    Duncan, Bruce Bartholow; Vigo, Álvaro; Hernandez, Émerson; Luft, Vivian Cristine; Ahlert, Hubert; Bergmann, Kaiser; Mota, Eduardo

    2013-06-01

    Information management in large multicenter studies requires a specialized approach. The Estudo Longitudinal da Saúde do Adulto (ELSA-Brasil - Brazilian Longitudinal Study for Adult Health) has created a Datacenter to enter and manage its data system. The aim of this paper is to describe the steps involved, including the information entry, transmission and management methods. A web system was developed in order to allow, in a safe and confidential way, online data entry, checking and editing, as well as the incorporation of data collected on paper. Additionally, a Picture Archiving and Communication System was implemented and customized for echocardiography and retinography. It stores the images received from the Investigation Centers and makes them available at the Reading Centers. Finally, data extraction and cleaning processes were developed to create databases in formats that enable analyses in multiple statistical packages.

  20. 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...

  1. 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

  2. Longitudinal volume changes of the pituitary gland in patients with schizotypal disorder and first-episode schizophrenia.

    Science.gov (United States)

    Takahashi, Tsutomu; Zhou, Shi-Yu; Nakamura, Kazue; Tanino, Ryoichiro; Furuichi, Atsushi; Kido, Mikio; Kawasaki, Yasuhiro; Noguchi, Kyo; Seto, Hikaru; Kurachi, Masayoshi; Suzuki, Michio

    2011-01-15

    An enlarged volume of the pituitary gland has been reported in the schizophrenia spectrum, possibly reflecting the hypothalamic-pituitary-adrenal (HPA) hyperactivity. However, it remains largely unknown whether the pituitary size longitudinally changes in the course of the spectrum disorders. In the present study, longitudinal magnetic resonance imaging (MRI) data were obtained from 18 patients with first-episode schizophrenia, 13 patients with schizotypal disorder, and 20 healthy controls. The pituitary volume was measured at baseline and follow-up (mean, 2.7 years) scans and was compared across groups. The pituitary volume was larger in the schizophrenia patients than controls at baseline, and both patient groups had significantly larger pituitary volume than controls at follow-up. In a longitudinal comparison, both schizophrenia (3.6%/year) and schizotypal (2.7%/year) patients showed significant pituitary enlargement compared with controls (-1.8%/year). In the schizophrenia patients, greater pituitary enlargement over time was associated with less improvement of delusions and higher scores for thought disorders at the follow-up. These findings suggest that the pituitary gland exhibits ongoing volume changes during the early course of the schizophrenia spectrum as a possible marker of state-related impairments. Copyright © 2010 Elsevier Inc. All rights reserved.

  3. Adolescents' media exposure may increase their cyberbullying behavior: a longitudinal study.

    Science.gov (United States)

    den Hamer, Anouk H; Konijn, Elly A

    2015-02-01

    The aim of this study was to examine the effect of adolescents' exposure to media portraying antisocial and risk behavior on cyberbullying behavior over time. Previous research established relatively high prevalence of cyberbullying behavior among adolescents, although not much is known about the possible predictors of cyberbullying behavior. This study examines the long-term effects of media exposure herein. Furthermore, we examined whether boys and girls differ in this respect. The long-term effects were tested in a longitudinal design with three waves (N = 1,005; age range, 11-17 years; 49% boys). Measured variables: cyberbullying behavior and exposure to media with antisocial and risk behavior content. Results of mixed-model analyses showed that higher levels of exposure to media with antisocial and risk behavior content significantly contributed to higher initial rates of cyberbullying behavior. Moreover, an increase in exposure to antisocial media content was significantly related to an increase in cyberbullying behavior over time. For both boys and girls, higher exposure to antisocial and risk behavior media content increases cyberbullying behavior over time though more clearly for boys than for girls. This study provided empirical support for the amplifying effect of exposure to antisocial media content on adolescents' cyberbullying behavior over time. Results are discussed in view of adolescents' media use and the larger theoretical framework. Copyright © 2015 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

  4. 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.

  5. 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.

  6. 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.

  7. Ventilation efficiency in a low-energy dwelling setting – a parameter study for larger rooms

    NARCIS (Netherlands)

    Dijkstra, D.; Loomans, M.G.L.C.; Hensen, J.L.M.; Cremers, B.E. (Bart)

    2016-01-01

    Mechanical balanced ventilation systems typically is applied in new and renovated dwellings in The Netherlands. The application assumes an adequate ventilation efficiency but this has not been confirmed for larger rooms (e.g. living rooms with kitchen attached). This study investigates ventilation

  8. 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…

  9. 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

  10. 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.

  11. 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.

  12. An exploratory longitudinal study of social and language outcomes in children with autism in bilingual home environments.

    Science.gov (United States)

    Zhou, Vanessa; Munson, Jeffrey A; Greenson, Jessica; Hou, Yan; Rogers, Sally; Estes, Annette M

    2017-12-01

    Little is known about outcomes of early intervention for children with autism spectrum disorder reared in bilingual homes. There are concerns that social communication deficits among children with autism spectrum disorder may reduce the developmental benefits of early intervention for children with autism spectrum disorder raised in bilingual environments. We conducted an exploratory analysis of cross-sectional and longitudinal data from a larger study to explore associations between home language environment and language ability and social skills in response to early autism spectrum disorder intervention. Participants, aged 12-26 months when recruited, were a subset of a larger 2-year, randomized intervention trial (ClinicalTrials.gov identifier: NCT00698997). Children from bilingual homes ( n = 13) began intervention with lower gesture use but otherwise demonstrated equal baseline language and social abilities as compared with age and nonverbal IQ-matched children from monolingual homes ( n = 24). Significant language growth was exhibited by children from both language groups and there was no moderating effect of home language environment. The bilingual home group demonstrated increased gesture use over the course of intervention as compared with the monolingual home group. Preliminary data revealed no basis for concerns regarding negative impact of a bilingual home environment on language or social development in young children with autism spectrum disorder.

  13. Digitomotography in Parkinson's disease: a cross-sectional and longitudinal study.

    Directory of Open Access Journals (Sweden)

    Walter Maetzler

    Full Text Available Motor symptoms in Parkinson's disease (PD are usually assessed with semi-quantitative tests such as the Unified PD Rating Scale (UPDRS which are limited by subjectivity, categorical design, and low sensitivity. Particularly bradykinesia as assessed e.g. with speeded index finger tapping exhibits low validity measures. This exploratory study set out to (i assess whether force transducer-based objective and quantitative analysis of motor coordination in index finger tapping is able to distinguish between PD patients and controls, and (ii assess longitudinal changes. Sixteen early-stage and 17 mid-stage PD patients as well as 18 controls were included in the cross-sectional part of the study; thirteen, 16 and 16 individuals of the respective groups agreed in a reassessment 12 months later. Frequency, force, rhythmicity, regularity and laterality of speeded and metronome paced tapping were recorded by digitomotography using a quantitative motor system ("Q-Motor". Analysis of cross-sectional data revealed most consistent differences between PD patients and controls in variability of tap performance across modalities assessed. Among PD patients, variability of taps and the ability to keep a given rhythm were associated with UPDRS motor and finger tapping scores. After 12 months, laterality parameters were reduced but no other parameters changed significantly. This data suggests that digitomotography provides quantitative and objective measures capable to differentiate PD from non-PD in a small cohort, however, the value of the assessment to track PD progression has to be further evaluated in larger cohorts of patients.

  14. 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…

  15. 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.

  16. 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.

  17. 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

  18. 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

  19. 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.

  20. 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.

  1. 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.

  2. 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....

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

    Energy Technology Data Exchange (ETDEWEB)

    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.)

  4. 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

  5. Why have microsaccades become larger?

    DEFF Research Database (Denmark)

    Hansen, Dan Witzner; Nyström, Marcus; Andersson, Richard

    2014-01-01

    -trackers compared to the systems used in the classical studies, in combination with the lack of a systematic algorithmic treatment of the overshoot. We hope that awareness of these discrepancies in microsaccade dynamics across eye structures will lead to more generally accepted definitions of microsaccades....... experts. The main reason was that the overshoots were not systematically detected by the algorithm and therefore not accurately accounted for. We conclude that one reason to why the reported size of microsaccades has increased is due to the larger overshoots produced by the modern pupil-based eye...

  6. 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…

  7. 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.

  8. Evidence of Big-Five personality changes following acquired brain injury from a prospective longitudinal investigation.

    Science.gov (United States)

    Leonhardt, Anne; Schmukle, Stefan C; Exner, Cornelia

    2016-03-01

    Many studies using different assessment methods have reported personality changes after acquired brain injury (ABI). However, to our knowledge, no prospective study has yet been conducted to examine whether previous cross-sectional and retrospective results can be replicated in a longitudinal prospective design. Further, because clinical control groups were only rarely used, it remains debatable if the personality changes found are unique to patients with ABI or if they also affect patients with other disabilities. This study examined personality change in 114 participants with different kinds of ABI, 1321 matched controls (general control, GC), and 746 matched participants with restrictive impairments other than brain injury (clinical control, CC) in a prospective longitudinal design using data from the panel survey Household, Income and Labour Dynamics in Australia (HILDA). Participants with ABI showed significantly larger declines in Extraversion and Conscientiousness compared with the GC group. When the ABI participants were compared with the CC group, only the difference in Conscientiousness remained significant. Our prospective data corroborate evidence from previous cross-sectional studies that patients with ABI experience larger declines in Extraversion and Conscientiousness than the general population. Whereas the effect on Conscientiousness was unique to patients with ABI, the decline in Extraversion was also observed in participants with other impairments. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Bunched beam longitudinal stability

    International Nuclear Information System (INIS)

    Baartman, R.

    1991-05-01

    Instabilities driven by narrow-band impedances can be stabilized by Landau damping arising from the synchrotron frequency spread due to the nonlinearity of the rf wave-form. We calculate stability diagrams for various phase space distributions. We find that distributions without tails are unstable in the 'negative mass' regime (inductive impedance below transition or capacitive impedance above transition). We also find that longitudinal instability thresholds of the (usually neglected) higher order radial modes are lower than expected. For example, the next to lowest dipole mode has a lower threshold than the lowest sextupole mode even though the latter has the larger growth rate in the absence of Landau damping. (Author) 5 refs., 5 figs

  10. Does functional disability mediate the pain-depression relationship in older adults with osteoarthritis? A longitudinal study in China.

    Science.gov (United States)

    Wang, Qian; Jayasuriya, Rohan; Man, Wing Young Nicola; Fu, Hua

    2015-03-01

    Older adults with osteoarthritis have been found to be impaired in physical functioning and report higher levels of depression. This study examined the relationships between pain, functional disability, and depression to test the activity restriction model in a cohort of 176 older adults in China. This model states that disability is a mediator for the relationship between pain and depression. Other investigators have found that pain and disability were two independent correlates of depression. In both cross-sectional and longitudinal analyses, the authors found that disability is a mediator, using commonly accepted methods (indirect effect 44%, Sobel Z = 4.07, P mediation effect was not seen when the outcome was residualized with the baseline value. When the baseline level of depression is residualized, the effect size of the relationship is reduced, requiring larger sample size to test its effect. © 2012 APJPH.

  11. 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...

  12. 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…

  13. 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

  14. Longitudinal diffusion MRI for treatment response assessment: Preliminary experience using an MRI-guided tri-cobalt 60 radiotherapy system.

    Science.gov (United States)

    Yang, Yingli; Cao, Minsong; Sheng, Ke; Gao, Yu; Chen, Allen; Kamrava, Mitch; Lee, Percy; Agazaryan, Nzhde; Lamb, James; Thomas, David; Low, Daniel; Hu, Peng

    2016-03-01

    To demonstrate the preliminary feasibility of a longitudinal diffusion magnetic resonance imaging (MRI) strategy for assessing patient response to radiotherapy at 0.35 T using an MRI-guided radiotherapy system (ViewRay). Six patients (three head and neck cancer, three sarcoma) who underwent fractionated radiotherapy were enrolled in this study. A 2D multislice spin echo single-shot echo planar imaging diffusion pulse sequence was implemented on the ViewRay system and tested in phantom studies. The same pulse sequence was used to acquire longitudinal diffusion data (every 2-5 fractions) on the six patients throughout the entire course of radiotherapy. The reproducibility of the apparent diffusion coefficient (ADC) measurements was assessed using reference regions and the temporal variations of the tumor ADC values were evaluated. In diffusion phantom studies, the ADC values measured on the ViewRay system matched well with reference ADC values with ViewRay MRI. Larger patient cohort studies are warranted to correlate the longitudinal diffusion measurements to patient outcomes. Such an approach may enable response-guided adaptive radiotherapy.

  15. SCI Longitudinal Aging Study: 40 Years of Research.

    Science.gov (United States)

    Krause, James S; Clark, Jillian M R; Saunders, Lee L

    2015-01-01

    The Spinal Cord Injury (SCI) Longitudinal Aging Study was initiated in 1973 and has conducted 8 assessments over the past 40 years. It was designed to help rehabilitation professionals understand the life situation of people with SCI, but it has developed into the most long-standing study of aging and SCI and has resulted in over 50 publications. Our purpose was to provide a detailed history of the study, response patterns, utilization of measures, and a summary of key findings reported in the literature. Five participant samples have been incorporated over the 40 years, with enrollment in 1973, 1984, 1993 (2 samples), and 2003. A total of 2,208 participants have completed 6,001 assessments, with a particularly large number of assessments among those who are more than 40 years post injury (n = 349). The overall results have indicated changing patterns of outcomes over time as persons with SCI age, with some notable declines in participation and health. There has been a survivor effect whereby persons who are more active, well-adjusted, and healthier live longer. This study has several important features that are required for longitudinal research including (a) consistency of follow-up, (b) consistency of measures over time, (c) addition of new participant samples to counteract attrition, and (d) inclusion of a large number of individuals who have reached aging milestones unparalleled in the literature. Data from this study can inform the literature on the natural course of aging with SCI.

  16. Montessori Preschool Elevates and Equalizes Child Outcomes: A Longitudinal Study.

    Science.gov (United States)

    Lillard, Angeline S; Heise, Megan J; Richey, Eve M; Tong, Xin; Hart, Alyssa; Bray, Paige M

    2017-01-01

    Quality preschool programs that develop the whole child through age-appropriate socioemotional and cognitive skill-building hold promise for significantly improving child outcomes. However, preschool programs tend to either be teacher-led and didactic, or else to lack academic content. One preschool model that involves both child-directed, freely chosen activity and academic content is Montessori. Here we report a longitudinal study that took advantage of randomized lottery-based admission to two public Montessori magnet schools in a high-poverty American city. The final sample included 141 children, 70 in Montessori and 71 in other schools, most of whom were tested 4 times over 3 years, from the first semester to the end of preschool (ages 3-6), on a variety of cognitive and socio-emotional measures. Montessori preschool elevated children's outcomes in several ways. Although not different at the first test point, over time the Montessori children fared better on measures of academic achievement, social understanding, and mastery orientation, and they also reported relatively more liking of scholastic tasks. They also scored higher on executive function when they were 4. In addition to elevating overall performance on these measures, Montessori preschool also equalized outcomes among subgroups that typically have unequal outcomes. First, the difference in academic achievement between lower income Montessori and higher income conventionally schooled children was smaller at each time point, and was not (statistically speaking) significantly different at the end of the study. Second, defying the typical finding that executive function predicts academic achievement, in Montessori classrooms children with lower executive function scored as well on academic achievement as those with higher executive function. This suggests that Montessori preschool has potential to elevate and equalize important outcomes, and a larger study of public Montessori preschools is warranted.

  17. Montessori Preschool Elevates and Equalizes Child Outcomes: A Longitudinal Study

    Directory of Open Access Journals (Sweden)

    Angeline S. Lillard

    2017-10-01

    Full Text Available Quality preschool programs that develop the whole child through age-appropriate socioemotional and cognitive skill-building hold promise for significantly improving child outcomes. However, preschool programs tend to either be teacher-led and didactic, or else to lack academic content. One preschool model that involves both child-directed, freely chosen activity and academic content is Montessori. Here we report a longitudinal study that took advantage of randomized lottery-based admission to two public Montessori magnet schools in a high-poverty American city. The final sample included 141 children, 70 in Montessori and 71 in other schools, most of whom were tested 4 times over 3 years, from the first semester to the end of preschool (ages 3–6, on a variety of cognitive and socio-emotional measures. Montessori preschool elevated children’s outcomes in several ways. Although not different at the first test point, over time the Montessori children fared better on measures of academic achievement, social understanding, and mastery orientation, and they also reported relatively more liking of scholastic tasks. They also scored higher on executive function when they were 4. In addition to elevating overall performance on these measures, Montessori preschool also equalized outcomes among subgroups that typically have unequal outcomes. First, the difference in academic achievement between lower income Montessori and higher income conventionally schooled children was smaller at each time point, and was not (statistically speaking significantly different at the end of the study. Second, defying the typical finding that executive function predicts academic achievement, in Montessori classrooms children with lower executive function scored as well on academic achievement as those with higher executive function. This suggests that Montessori preschool has potential to elevate and equalize important outcomes, and a larger study of public Montessori

  18. 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…

  19. 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

  20. 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

  1. 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

  2. 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…

  3. 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...

  4. Prevalence and co-occurrence of addictive behaviors among former alternative high school youth: A longitudinal follow-up study.

    Science.gov (United States)

    Sussman, Steve; Pokhrel, Pallav; Sun, Ping; Rohrbach, Louise A; Spruijt-Metz, Donna

    2015-09-01

    Recent work has studied addictions using a matrix measure, which taps multiple addictions through single responses for each type. This is the first longitudinal study using a matrix measure. We investigated the use of this approach among former alternative high school youth (average age = 19.8 years at baseline; longitudinal n = 538) at risk for addictions. Lifetime and last 30-day prevalence of one or more of 11 addictions reviewed in other work was the primary focus (i.e., cigarettes, alcohol, hard drugs, shopping, gambling, Internet, love, sex, eating, work, and exercise). These were examined at two time-points one year apart. Latent class and latent transition analyses (LCA and LTA) were conducted in Mplus. Prevalence rates were stable across the two time-points. As in the cross-sectional baseline analysis, the 2-class model (addiction class, non-addiction class) fit the data better at follow-up than models with more classes. Item-response or conditional probabilities for each addiction type did not differ between time-points. As a result, the LTA model utilized constrained the conditional probabilities to be equal across the two time-points. In the addiction class, larger conditional probabilities (i.e., 0.40-0.49) were found for love, sex, exercise, and work addictions; medium conditional probabilities (i.e., 0.17-0.27) were found for cigarette, alcohol, other drugs, eating, Internet and shopping addiction; and a small conditional probability (0.06) was found for gambling. Persons in an addiction class tend to remain in this addiction class over a one-year period.

  5. 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…

  6. 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…

  7. 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.

  8. 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

  9. 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

  10. Concurrent polysubstance use in a longitudinal study of US youth: associations with sexual orientation.

    Science.gov (United States)

    Kecojevic, Aleksandar; Jun, Hee-Jin; Reisner, Sari L; Corliss, Heather L

    2017-04-01

    To estimate longitudinal associations between self-reported sexual orientation and past-year polysubstance use among youth, and test how gender, age and early onset of tobacco and alcohol use contributed to variation in polysubstance use. Longitudinal community-based cohort of US adolescents from the Growing Up Today Study (GUTS 1) (n = 16 873) followed from ages 12-29 years. United States of America. A total of 13 519 individuals (7839 females; 5680 males) who responded to at least one of five self-administered questionnaires from 1999 to 2010. Ninety-three per cent reported their race/ethnicity as non-Hispanic white. Multivariable repeated measures generalized estimating equations estimated relative risks (RRs) of concurrent polysubstance use (i.e. past 12-month use of three or more substances) comparing sexual orientation minority youth [i.e. mostly heterosexual (MH), bisexual (BI), gay/lesbian (GL)] to their same-gender, completely heterosexual (CH) counterparts. Mediation analyses tested whether early onset of tobacco and/or alcohol use explained relationships between sexual orientation and concurrent polysubstance use. Compared with their same-gender CH peers, sexual minorities evidenced higher risk for concurrent polysubstance use over all repeated measures [risk ratios (RRs) for sexual minority subgroups: from 1.63-2.91, P-values: sexual minorities and CHs were larger among females than males (P-values for sexual orientation × gender interactions were sexual orientation × age interactions were Sexual minorities' younger age of smoking and/or drinking initiation contributed to their elevated polysubstance use (% of effect explained was between 9.4-24.3, P-values: 0.04-Sexual minority youth in the United States, and in particular younger females, appear to be at disproportionate risk for concurrent past-year polysubstance use. Early onset of smoking and drinking may contribute to elevated risk of polysubstance use among sexual minorities. © 2016

  11. 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

  12. 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.

  13. A longitudinal study: changes in cortical thickness and surface area during pubertal maturation.

    Directory of Open Access Journals (Sweden)

    Megan M Herting

    Full Text Available Sex hormones have been shown to contribute to the organization and function of the brain during puberty and adolescence. Moreover, it has been suggested that distinct hormone changes in girls versus boys may contribute to the emergence of sex differences in internalizing and externalizing behavior during adolescence. In the current longitudinal study, the influence of within-subject changes in puberty (physical and hormonal on cortical thickness and surface area was examined across a 2-year span, while controlling for age. Greater increases in Tanner Stage predicted less superior frontal thinning and decreases in precuneus surface area in both sexes. Significant Tanner Stage and sex interactions were also seen, with less right superior temporal thinning in girls but not boys, as well as greater decreases in the right bank of the superior temporal sulcus surface area in boys compared to girls. In addition, within-subject changes in testosterone over the 2-year follow-up period were found to relate to decreases in middle superior frontal surface area in boys, but increases in surface area in girls. Lastly, larger increases in estradiol in girls predicted greater middle temporal lobe thinning. These results show that within-subject physical and hormonal markers of puberty relate to region and sex-specific changes in cortical development across adolescence.

  14. A longitudinal study: changes in cortical thickness and surface area during pubertal maturation.

    Science.gov (United States)

    Herting, Megan M; Gautam, Prapti; Spielberg, Jeffrey M; Dahl, Ronald E; Sowell, Elizabeth R

    2015-01-01

    Sex hormones have been shown to contribute to the organization and function of the brain during puberty and adolescence. Moreover, it has been suggested that distinct hormone changes in girls versus boys may contribute to the emergence of sex differences in internalizing and externalizing behavior during adolescence. In the current longitudinal study, the influence of within-subject changes in puberty (physical and hormonal) on cortical thickness and surface area was examined across a 2-year span, while controlling for age. Greater increases in Tanner Stage predicted less superior frontal thinning and decreases in precuneus surface area in both sexes. Significant Tanner Stage and sex interactions were also seen, with less right superior temporal thinning in girls but not boys, as well as greater decreases in the right bank of the superior temporal sulcus surface area in boys compared to girls. In addition, within-subject changes in testosterone over the 2-year follow-up period were found to relate to decreases in middle superior frontal surface area in boys, but increases in surface area in girls. Lastly, larger increases in estradiol in girls predicted greater middle temporal lobe thinning. These results show that within-subject physical and hormonal markers of puberty relate to region and sex-specific changes in cortical development across adolescence.

  15. 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.

  16. Defining SNAP by cross-sectional and longitudinal definitions of neurodegeneration.

    Science.gov (United States)

    Wisse, L E M; Das, S R; Davatzikos, C; Dickerson, B C; Xie, S X; Yushkevich, P A; Wolk, D A

    2018-01-01

    Suspected non-Alzheimer's pathophysiology (SNAP) is a biomarker driven designation that represents a heterogeneous group in terms of etiology and prognosis. SNAP has only been identified by cross-sectional neurodegeneration measures, whereas longitudinal measures might better reflect "active" neurodegeneration and might be more tightly linked to prognosis. We compare neurodegeneration defined by cross-sectional 'hippocampal volume' only (SNAP/L-) versus both cross-sectional and longitudinal 'hippocampal atrophy rate' (SNAP/L+) and investigate how these definitions impact prevalence and the clinical and biomarker profile of SNAP in Mild Cognitive Impairment (MCI). 276 MCI patients from ADNI-GO/2 were designated amyloid "positive" (A+) or "negative" (A-) based on their florbetapir scan and neurodegeneration 'positive' or 'negative' based on cross-sectional hippocampal volume and longitudinal hippocampal atrophy rate. 74.1% of all SNAP participants defined by the cross-sectional definition of neurodegeneration also met the longitudinal definition of neurodegeneration, whereas 25.9% did not. SNAP/L+ displayed larger white matter hyperintensity volume, a higher conversion rate to dementia over 5 years and a steeper decline on cognitive tasks compared to SNAP/L- and the A- CN group. SNAP/L- had more abnormal values on neuroimaging markers and worse performance on cognitive tasks than the A- CN group, but did not show a difference in dementia conversion rate or longitudinal cognition. Using a longitudinal definition of neurodegeneration in addition to a cross-sectional one identifies SNAP participants with significant cognitive decline and a worse clinical prognosis for which cerebrovascular disease may be an important driver.

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

    Science.gov (United States)

    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.

  18. 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…

  19. 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

  20. In vivo toxicologic study of larger silica nanoparticles in mice

    Directory of Open Access Journals (Sweden)

    Chan WT

    2017-04-01

    Full Text Available Wai-Tao Chan,1–3 Cheng-Che Liu,4 Jen-Shiu Chiang Chiau,5 Shang-Ting Tsai,6 Chih-Kai Liang,6 Mei-Lien Cheng,5 Hung-Chang Lee,7,8 Chun-Yun Yeung,1,3,9 Shao-Yi Hou2,6 1Department of Pediatric Gastroenterology, Hepatology and Nutrition, MacKay Children’s Hospital, 2Graduate Institute of Engineering Technology, National Taipei University of Technology, 3Mackay Medicine, Nursing, and Management College, 4Institute of Preventive Medicine, National Defense Medical Center, Taipei, 5Department of Medical Research, MacKay Memorial Hospital, Hsinchu, 6Graduate Institute of Biochemical and Biomedical Engineering, National Taipei University of Technology, Taipei, 7Department of Pediatrics, MacKay Memorial Hospital, Hsinchu, 8Department of Pediatrics, Taipei Medical University, Taipei, 9Department of Medicine, Mackay Medical College, New Taipei, Taiwan, Republic of China Abstract: Silica nanoparticles (SiNPs are being studied and used for medical purposes. As nanotechnology grows rapidly, its biosafety and toxicity have frequently raised concerns. However, diverse results have been reported about the safety of SiNPs; several studies reported that smaller particles might exhibit toxic effects to some cell lines, and larger particles of 100 nm were reported to be genotoxic to the cocultured cells. Here, we investigated the in vivo toxicity of SiNPs of 150 nm in various dosages via intravenous administration in mice. The mice were observed for 14 days before blood examination and histopathological assay. All the mice survived and behaved normally after the administration of nanoparticles. No significant weight change was noted. Blood examinations showed no definite systemic dysfunction of organ systems. Histopathological studies of vital organs confirmed no SiNP-related adverse effects. We concluded that 150 nm SiNPs were biocompatible and safe for in vivo use in mice. Keywords: in vivo, mice, silica nanoparticle, nanotoxicity

  1. 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.

  2. 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 ...

  3. 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.

  4. Longitudinal strain predicts left ventricular mass regression after aortic valve replacement for severe aortic stenosis and preserved left ventricular function.

    Science.gov (United States)

    Gelsomino, Sandro; Lucà, Fabiana; Parise, Orlando; Lorusso, Roberto; Rao, Carmelo Massimiliano; Vizzardi, Enrico; Gensini, Gian Franco; Maessen, Jos G

    2013-11-01

    We explored the influence of global longitudinal strain (GLS) measured with two-dimensional speckle-tracking echocardiography on left ventricular mass regression (LVMR) in patients with pure aortic stenosis (AS) and normal left ventricular function undergoing aortic valve replacement (AVR). The study population included 83 patients with severe AS (aortic valve area regression (all P regression in patients with pure AS undergoing AVR. Our findings must be confirmed by further larger studies.

  5. 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…

  6. 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.

  7. Research on a Novel Exciting Method for a Sandwich Transducer Operating in Longitudinal-Bending Hybrid Modes

    Directory of Open Access Journals (Sweden)

    Yingxiang Liu

    2017-06-01

    Full Text Available A novel exciting method for a sandwich type piezoelectric transducer operating in longitudinal-bending hybrid vibration modes is proposed and discussed, in which the piezoelectric elements for the excitations of the longitudinal and bending vibrations share the same axial location, but correspond to different partitions. Whole-piece type piezoelectric plates with three separated partitions are used, in which the center partitions generate the first longitudinal vibration, while the upper and lower partitions produce the second bending vibration. Detailed comparisons between the proposed exciting method and the traditional one were accomplished by finite element method (FEM calculations, which were further verified by experiments. Compared with the traditional exciting method using independent longitudinal ceramics and bending ceramics, the proposed method achieves higher electromechanical coupling factors and larger vibration amplitudes, especially for the bending vibration mode. This novel exciting method for longitudinal-bending hybrid vibrations has not changed the structural dimensions of the sandwich transducer, but markedly improves the mechanical output ability, which makes it very helpful and meaningful in designing new piezoelectric actuators operated in longitudinal-bending hybrid vibration modes.

  8. 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).

  9. Potential Reciprocal Relationship between Motivation and Achievement: A Longitudinal Study

    Science.gov (United States)

    Liu, Yuan; Hou, Shumeng

    2018-01-01

    Among the non-cognitive factors that influence academic achievement, intrinsic motivation has been found to be a potential reciprocal factor. The present study aims to determine the causal relationship between other types of motivation and academic achievement. For this purpose, a large-scale data survey, the National Education Longitudinal Study…

  10. 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

  11. 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,…

  12. 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.

  13. 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.

  14. 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.

  15. 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…

  16. 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…

  17. 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…

  18. 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

  19. Investigation of longitudinal control system for a small hydrofoil boat

    Science.gov (United States)

    Phillips, W. H.; Shaughnessy, J. D.

    1976-01-01

    An analysis of a hydromechanical system for longitudinal control of a small hydrofoil boat is presented. The system incorporates height and acceleration sensors operating flaps on the foils through a mechanical linkage. Effects of some of the system parameters on the stability and response to waves are shown. The results indicate that the system is capable of providing adequate stability, but the response to stern waves at low frequencies is larger than desired.

  20. A cautionary note on generalized linear models for covariance of unbalanced longitudinal data

    KAUST Repository

    Huang, Jianhua Z.

    2012-03-01

    Missing data in longitudinal studies can create enormous challenges in data analysis when coupled with the positive-definiteness constraint on a covariance matrix. For complete balanced data, the Cholesky decomposition of a covariance matrix makes it possible to remove the positive-definiteness constraint and use a generalized linear model setup to jointly model the mean and covariance using covariates (Pourahmadi, 2000). However, this approach may not be directly applicable when the longitudinal data are unbalanced, as coherent regression models for the dependence across all times and subjects may not exist. Within the existing generalized linear model framework, we show how to overcome this and other challenges by embedding the covariance matrix of the observed data for each subject in a larger covariance matrix and employing the familiar EM algorithm to compute the maximum likelihood estimates of the parameters and their standard errors. We illustrate and assess the methodology using real data sets and simulations. © 2011 Elsevier B.V.

  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…

  2. 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 ...

  3. 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.)

  4. 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.)

  5. 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...

  6. Larger right posterior parietal volume in action video game experts: a behavioral and voxel-based morphometry (VBM study.

    Directory of Open Access Journals (Sweden)

    Satoshi Tanaka

    Full Text Available Recent studies suggest that action video game players exhibit superior performance in visuospatial cognitive tasks compared with non-game players. However, the neural basis underlying this visuospatial cognitive performance advantage remains largely unknown. The present human behavioral and imaging study compared gray matter volume in action video game experts and non-experts using structural magnetic resonance imaging and voxel-based morphometry analysis. The results revealed significantly larger gray matter volume in the right posterior parietal cortex in experts compared with non-experts. Furthermore, the larger gray matter volume in the right posterior parietal cortex significantly correlated with individual performance in a visual working memory task in experts. These results suggest that differences in brain structure may be linked to extensive video game play, leading to superior visuospatial cognitive performance in action video game experts.

  7. In vivo longitudinal chromatic aberration of pseudophakic eyes.

    Science.gov (United States)

    Siedlecki, Damian; Jóźwik, Agnieszka; Zając, Marek; Hill-Bator, Aneta; Turno-Kręcicka, Anna

    2014-02-01

    To present the results of longitudinal chromatic aberration measurements on two groups of pseudophakic eyes in comparison to healthy eyes. The longitudinal chromatic aberration of the eye, defined as chromatic difference of refraction with disabled accommodation, was measured with the use of a visual refractometer with a custom-designed target illuminator consisting of a narrow-band RGB diode (blue λb = 470 ± 15 nm; green λg = 525 ± 18 nm; red λr = 660 ± 10 nm). The measurements were performed on nine eyes implanted with AcrySof IQ SN60WF, 14 eyes implanted with AcrySof SA60AT, and 10 phakic eyes under cycloplegia. The mean values of the longitudinal chromatic aberration between 470 and 660 nm for the control group was 1.12 ± 0.14 D. For SA60AT group, it was 1.45 ± 0.42 D whereas for SN60WF it was 1.17 ± 0.52 D. The statistical test showed significant difference between SA60AT and the control group (p chromatic aberration in vivo can be easily and reliably estimated with an adapted visual refractometer. The two groups of pseudophakic eyes measured in this study showed different values of chromatic aberration. Its magnitude for SA60AT group was significantly larger than for the control group whereas for SN60WF the difference was not significant. The optical material used for intraocular lens design may have significant influence on the magnitude of the chromatic aberration of the pseudophakic eye, and therefore on its optical and visual performance in polychromatic light.

  8. Language Learning at Key Stage 2: Findings from a Longitudinal Study

    Science.gov (United States)

    Cable, Carrie; Driscoll, Patricia; Mitchell, Rosamond; Sing, Sue; Cremin, Teresa; Earl, Justine; Eyres, Ian; Holmes, Bernardette; Martin, Cynthia; Heins, Barbara

    2012-01-01

    This paper discusses some of the findings from a 3-year longitudinal study of language learning in the upper stage of English primary schools, i.e. at Key Stage 2. This largely qualitative study (commissioned by the then Department for Children, Schools and Families) was designed to explore and document developing provision and practice in a…

  9. 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…

  10. The contingency of intermedia agenda setting: a longitudinal study in Belgium

    NARCIS (Netherlands)

    Vliegenthart, R.; Walgrave, S.

    2008-01-01

    This large-scale study investigates how intermedia agenda-setting effects are moderated by five factors: (1) lag length; (2) medium type; (3) language/institutional barriers; (4) issue type; and (5) election or non-election context. Longitudinal analyses of daily attention to twenty-five issues in

  11. 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...

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

    Science.gov (United States)

    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.

  13. TWITCH PARAMETERS IN TRANSVERSAL AND LONGITUDINAL BICEPS BRACHII RESPONSE

    Directory of Open Access Journals (Sweden)

    Boštjan Šimunič

    2010-01-01

    Full Text Available Assessment of the contractile properties of skeletal muscles is continuing to be an important issue and a difficult task methodologically. Longitudinal direction of skeletal muscle contraction blurs intrinsic muscle belly contractile properties with many factors. This study evaluates and explains contractile properties such as: delay time (Td, contraction time (Tc, half relaxation time (Tr and maximal amplitude (Dm extracted from twitch transversal response and compare them with torque response. In fifteen healthy males (age 23.7 ± 3.4 years isometric twitch transversal and torque responses were simultaneously recorded during graded electrically elicited contractions in the biceps brachii muscle. The amplitude of electrical stimulation was increased in 5 mA steps from a threshold up to a maximal response. The muscles’ belly transversal response was measured by a high precision mechanical displacement sensor while elbow joint torque was calculated from force readings. Results indicate a parabolic relation between the transversal displacement and the torque Dm. A significantly shorter Tc was found in transversal response without being correlated to torque Tc (r = -0.12; > 0.05. A significant correlation was found between torque Tc and the time occurrence of the second peak in the transversal response (r = 0.83; < 0.001. Electrical stimulation amplitude dependant variation of the Tc was notably different in transversal than in torque response. Td was similar at submaximal and maximal responses but larger in transversal at just above threshold contractions. Tr has a similar linear trend in both responses, however, the magnitude and the slope are much larger in the transversal response. We could conclude that different mechanisms affect longitudinal and transversal twitch skeletal muscle deformations. Contractile properties extracted from the transversal response enable alternative insights into skeletal muscle contraction mechanics.

  14. Sampling strategies to measure the prevalence of common recurrent infections in longitudinal studies

    Directory of Open Access Journals (Sweden)

    Luby Stephen P

    2010-08-01

    Full Text Available Abstract Background Measuring recurrent infections such as diarrhoea or respiratory infections in epidemiological studies is a methodological challenge. Problems in measuring the incidence of recurrent infections include the episode definition, recall error, and the logistics of close follow up. Longitudinal prevalence (LP, the proportion-of-time-ill estimated by repeated prevalence measurements, is an alternative measure to incidence of recurrent infections. In contrast to incidence which usually requires continuous sampling, LP can be measured at intervals. This study explored how many more participants are needed for infrequent sampling to achieve the same study power as frequent sampling. Methods We developed a set of four empirical simulation models representing low and high risk settings with short or long episode durations. The model was used to evaluate different sampling strategies with different assumptions on recall period and recall error. Results The model identified three major factors that influence sampling strategies: (1 the clustering of episodes in individuals; (2 the duration of episodes; (3 the positive correlation between an individual's disease incidence and episode duration. Intermittent sampling (e.g. 12 times per year often requires only a slightly larger sample size compared to continuous sampling, especially in cluster-randomized trials. The collection of period prevalence data can lead to highly biased effect estimates if the exposure variable is associated with episode duration. To maximize study power, recall periods of 3 to 7 days may be preferable over shorter periods, even if this leads to inaccuracy in the prevalence estimates. Conclusion Choosing the optimal approach to measure recurrent infections in epidemiological studies depends on the setting, the study objectives, study design and budget constraints. Sampling at intervals can contribute to making epidemiological studies and trials more efficient, valid

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

    Science.gov (United States)

    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

  16. Longitudinal association between marital disruption and child BMI and obesity.

    Science.gov (United States)

    Arkes, Jeremy

    2012-08-01

    This research examines whether family disruptions (i.e., divorces and separation) contribute to children's weight problems. The sample consists of 7,299 observations for 2,333 children, aged 5-14, over the 1986-2006 period, from a US representative sample from the Child and Young Adult Survey accompanying the National Longitudinal Survey of Youth (NLSY). The study uses individual-fixed-effects models in a longitudinal framework to compare children's BMI and weight problems before and after a disruption. Furthermore, besides doing a before-after comparison for children, the study also estimates the effects at various periods relative to the disruption in order to examine whether children are affected before the disruption and whether any effects change as time passes from the disruption, as some effects may be temporary or slow to develop. Despite having a larger sample than the previous studies, the results provide no evidence that, on average, children's BMI and BMI percentile scores (measured with continuous outcomes) are affected before the disruption, after the disruption, and as time passes from the disruption, relative to a baseline period a few years before the disruption. However, children experiencing a family disruption do have an increased risk of obesity (having a BMI percentile score of 95 or higher) in the two years leading up to the disruption as well as after the disruption, and as time passes from the disruption.

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

    International Nuclear Information System (INIS)

    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

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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,…

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

    Science.gov (United States)

    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.

  1. Dynamic Boundaries of Action Based Learning: the Longitudinal Impact (Invited Paper

    Directory of Open Access Journals (Sweden)

    D. Song

    2015-08-01

    Full Text Available How do communities and group-based efforts create, learn and evolve? This paper argues that communities are dynamic, continuously creating connections through cyclical learning processes, regardless of how tight or loosely formulated group based efforts are (Hall et al. 2012. Learning cycles or epicycles processes are relevant for action-based investigation within organizational and social structures. The question of behaviors across boundaries or groups maybe influenced by their positioning within a larger adaptive system, including the type of focus, determined goals and the type of connections that have been developed over time (longitudinally. These types of community or group efforts can be described as autopoietic systems, which operate within larger adaptive societal webs (Nousala 2014. The learning methodologies involved in investigating these types of dynamic phenomena need themselves to be dynamic. These methods can be viewed through longitudinal cycles, (which are essentially feedback loops that include extensive reflective time lines, integration before repetition exposing these epicycles at work. The continuous recording of various processes through epicycles (which are the basis for learning cycles provide a means to "qualitatively measuring" change, which would normally go unseen (Hall et. al 2012; Hall et al. 2005; Nousala and Hall 2008; Wenger and Synder 2000; Garduno et al. 2015.

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

  5. Annual spatiotemporal migration schedules in three larger insectivorous birds

    DEFF Research Database (Denmark)

    Jacobsen, Lars Bo; Jensen, Niels Odder; Willemoes, Mikkel

    2017-01-01

    Background: Knowledge of spatiotemporal migration patterns is important for our understanding of migration ecology and ultimately conservation of migratory species. We studied the annual migration schedules of European nightjar, a large nocturnal insectivore and compared it with two other larger ...

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

    Science.gov (United States)

    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…

  7. Weaving leadership longitudinally: a qualitative study on faculty development

    OpenAIRE

    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...

  8. A longitudinal study of structural brain network changes with normal aging

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    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.

  10. 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

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  12. Communication Competence, Psychological Well-being, and the Mediating Role of Coping Efforts among Women with Breast Cancer: Cross-sectional and Longitudinal Evidence

    Science.gov (United States)

    Shim, Minsun; Mercer Kollar, Laura M.; Roberts, Linda; Gustafson, David

    2015-01-01

    Despite existing research identifying psychological benefits of patients’ interpersonal competence in various contexts, little longitudinal research has addressed underlying mechanism(s). To address this limitation, we examined both the cross-sectional and longitudinal associations between cancer patients’ communication competence in close relationships and psychological well-being, as well as the mediating role of coping efforts. Data came from a larger project with women with breast cancer (N = 661), recruited from April 2005 to May 2007 at three large university-affiliated cancer centers in the U.S. to study the effects of an Internet-based system providing patients and families with a range of services. The present study focused on survey data at baseline, 6 weeks, and 12 weeks after the intervention (controlling for the possible effects of the intervention). Results from both cross-sectional and longitudinal analyses indicated that competence in open communication between patients and their close support persons had a positive association with patients’ psychological well-being and that approach coping efforts partially mediated this association. We discussed the implications and limitations of the study. PMID:25793748

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

    Science.gov (United States)

    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…

  14. 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.

  15. 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.

  16. 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

  17. 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

  18. 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

  19. 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

  20. 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…

  1. 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....

  2. Ohmic losses in coaxial resonators with longitudinal inner-outer corrugation

    Energy Technology Data Exchange (ETDEWEB)

    Shenyong Hou, A. [Terahertz Science and Technology Research Center, University of Electronics Science and Technology of China, Chengdu 610054 (China); Yangtze Normal University, Chongqing 408001 (China); Sheng Yu, B.; Hongfu Li, C.; Qixiang Zhao, D. [Terahertz Science and Technology Research Center, University of Electronics Science and Technology of China, Chengdu 610054 (China); Xiang Li, E. [Terahertz Science and Technology Research Center, University of Electronics Science and Technology of China, Chengdu 610054 (China); Queen Mary University of London, London E1 4NS (United Kingdom)

    2013-05-15

    In this paper, a coaxial resonator with longitudinal inner-outer corrugation is introduced. Its eigen-equation and expression of ohmic losses are derived. Ohmic losses in the cavity are investigated. Results show that ohmic losses in the outer and inner conductors share a similar variation trend, while the former is larger than the later. What's more, changes of the inner and outer slot depth and width induce different variations of ohmic losses on the surface of the inner and outer conductors.

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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…

  7. Pathways from fertility history to later life health: Results from analyses of the English Longitudinal Study of Ageing

    Directory of Open Access Journals (Sweden)

    Emily Grundy

    2015-01-01

    Full Text Available Background: Previous research shows associations between fertility histories and later life health. The childless, those with large families, and those with a young age at entry to parenthood generally have higher mortality and worse health than parents of two or three children. These associations are hypothesised to reflect a range of biosocial influences, but underlying mechanisms are poorly understood. Objective: To identify pathways from fertility histories to later life health by examining mediation through health-related behaviours, social support and strain, and wealth. Additionally to examine mediation through allostatic load - an indicator of multisystem physical dysregulation, hypothesised to be an outcome of chronic stress. Methods: Associations between fertility histories, mediators, and outcomes were analysed using path models. Data were drawn from the English Longitudinal Study of Ageing. Outcomes studied were a measure of allostatic load based on 9 biomarkers and self-reported long-term illness which limited activities. Results: Early parenthood (Conclusions: In England early parenthood and larger family size are associated with less wealth and poorer health behaviours and this accounts for much of the association with health. At least part of this operates through stress-related physiological dysfunction (allostatic load.

  8. Investigation of a rotary ultrasonic motor using a longitudinal vibrator and spiral fin rotor.

    Science.gov (United States)

    Peng, Taijiang; Wu, Xiaoyu; Liang, Xiong; Shi, Hongyan; Luo, Feng

    2015-08-01

    A Langevin transducer can provide longitudinal vibration with larger amplitude while also possessing a greater fatigue life than other types of piezoelectric vibrators. A novel rotary Ultrasonic Motor (USM) was proposed based on the use of a longitudinal transducer (acting as the stator) and a spiral fin rotor: the front cover of the Langevin transducer was designed as a double-layer cup-shaped structure, with the rotor sustained by the inner-layer, and the bearing cover fixed to the outer-layer; the rotor consisted of a shaft and spiral fins which acted as the elastic coupler. It is different from a traditional traveling USM, because the stator provides longitudinal vibration and the rotor generates the elliptical motion. This paper analyzed the motion locus equation of the fin contact points. Additionally, a theoretical analysis was performed in regards to the mechanism and the motor's rotor motion characteristics, which demonstrates the relationships among the motor's driving force, the torque, the revolution speed, and the motor structure parameters. A motor prototype has been manufactured and surveyed to demonstrate the motor performance. The relationships between the amplitude and the preload on the rotor, the free revolution speed, and the torque of the motor have also been studied. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. 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

  10. Big data in Parkinson's disease: using smartphones to remotely detect longitudinal disease phenotypes.

    Science.gov (United States)

    Prince, John; Arora, Siddharth; de Vos, Maarten

    2018-04-26

    To better understand the longitudinal characteristics of Parkinson's disease (PD) through the analysis of finger tapping and memory tests collected remotely using smartphones. Using a large cohort (312 PD subjects and 236 controls) of participants in the mPower study, we extract clinically validated features from a finger tapping and memory test to monitor the longitudinal behaviour of study participants. We investigate any discrepancy in learning rates associated with motor and non-motor tasks between PD subjects and healthy controls. The ability of these features to predict self-assigned severity measures is assessed whilst simultaneously inspecting the severity scoring system for floor-ceiling effects. Finally, we study the relationship between motor and non-motor longitudinal behaviour to determine if separate aspects of the disease are dependent on one another. We find that the test performances of the most severe subjects show significant correlations with self-assigned severity measures. Interestingly, less severe subjects do not show significant correlations, which is shown to be a consequence of floor-ceiling effects within the mPower self-reporting severity system. We find that motor performance after practise is a better predictor of severity than baseline performance suggesting that starting performance at a new motor task is less representative of disease severity than the performance after the test has been learnt. We find PD subjects show significant impairments in motor ability as assessed through the alternating finger tapping (AFT) test in both the short- and long-term analyses. In the AFT and memory tests we demonstrate that PD subjects show a larger degree of longitudinal performance variability in addition to requiring more instances of a test to reach a steady state performance than healthy subjects. Our findings pave the way forward for objective assessment and quantification of longitudinal learning rates in PD. This can be particularly

  11. 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.

  12. 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.

  13. Longitudinal safety evaluation of electric vehicles with the partial wireless charging lane on freeways.

    Science.gov (United States)

    Li, Ye; Wang, Wei; Xing, Lu; Fan, Qi; Wang, Hao

    2018-02-01

    As an environment friendly transportation mode, the electric vehicle (EV) has drawn an increasing amount of attention from governments, vehicle manufactories and researchers recently. One of the biggest issue impeding EV's popularization associates with the charging process. The wireless charging lane (WCL) has been proposed as a convenient charging facility for EVs. Due to the high costs, the application of WCL on the entire freeways is impractical in the near future, while the partial WCL (PWCL) may be a feasible solution. This study aims to evaluate longitudinal safety of EVs with PWCL on freeways based on simulations. The simulation experiments are firstly designed, including deployment of PWCL on freeways and distribution of state of charge (SOC) of EVs. Then, a vehicle behavior model for EVs is proposed based on the intelligent driver model (IDM). Two surrogate safety measures, derived from time-to-collision (TTC), are utilized as indicators for safety evaluations. Sensitivity analysis is also conducted for related factors. Results show that the distribution of EVs' SOC significantly affect longitudinal safety when the PWCL is utilized. The low SOC in traffic consisting of EVs has the negative effect on longitudinal safety. The randomness and incompliance of EV drivers worsens the safety performance. The sensitivity analysis indicates that the larger maximum deceleration rate results in the higher longitudinal crash risks of EVs, while the length of PWCL has no monotonous effect. Different TTC thresholds also show no impact on results. A case study shows the consistent results. Based on the findings, several suggestions are discussed for EVs' safety improvement. Results of this study provide useful information for freeway safety when EVs are applied in the future. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. 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

  15. 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.

  16. 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

  17. 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...

  18. Dispersal, phenology and predicted abundance of the larger grain ...

    African Journals Online (AJOL)

    The phenology and dispersal of the larger grain borer (LGB) in Africa is described, and comparisons are made between prediction of LGB numbers from laboratory studies and predictions from multiple linear models derived from trapping data in the field. The models were developed in Mexico and Kenya, using ...

  19. 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...

  20. 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.

  1. Longitudinal Study of Direct Instruction Effects from First through Third Grades

    Science.gov (United States)

    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…

  2. 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.

  3. 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

  4. 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.

  5. 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.

  6. 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.

  7. Mindful Parenting and Emotion Socialization Practices: Concurrent and Longitudinal Associations.

    Science.gov (United States)

    McKee, Laura G; Parent, Justin; Zachary, Chloe R; Forehand, Rex

    2017-11-01

    Caregivers play a crucial role in the socialization of youth emotion understanding, competence, and regulation, which are implicated in youth social and emotional health; however, there is less understanding of parental psychosocial or cognitive factors, like mindful parenting, that may be associated with the use of particular emotion socialization (ES) strategies. This study tests a model of the cross-sectional and short-term longitudinal associations between mindful parenting and supportive and nonsupportive ES strategies in a community sample of parents (N = 246; 63.8% mothers) of youth ranging from ages 3-12. Caregivers reported on mindful parenting and ES strategies at two time points 4 months apart. The structural equation model indicated that higher levels of mindful parenting are positively related to supportive ES responses and negatively related to nonsupportive ES responses both concurrently and over time. The longitudinal association between mindful parenting and nonsupportive, but not supportive, ES was marginally larger for fathers as compared to mothers. Given the documented impact of ES strategies on youth emotional and behavioral outcomes and interventions emerging to educate parents about how to provide a healthy emotional atmosphere, incorporating a focus on mindful parenting strategies may provide one pathway to increase supportive responses and decrease nonsupportive ones. © 2017 Family Process Institute.

  8. 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...

  9. [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.

  10. 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

  11. When the proton becomes larger

    CERN Multimedia

    CERN Bulletin

    2011-01-01

    The TOTEM experiment at the LHC has just confirmed that, at high energy, protons behave as if they were becoming larger. In more technical terms, their total cross-section – a parameter linked to the proton-proton interaction probability – increases with energy. This phenomenon, expected from previous measurements performed at much lower energy, has now been confirmed for the first time at the LHC’s unprecedented energy.   One arm of a TOTEM T2 detector during its installation at interaction point 5. A composite particle like the proton is a complex system that in no way resembles a static Lego construction: sub-components move inside and interactions keep the whole thing together, but in a very dynamic way. This partly explains why even the very common proton can still be hiding secrets about its nature, decades after its discovery. One way of studying the inner properties of protons is to observe how they interact with each other, which, in technical terms, i...

  12. 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 ...

  13. The Need for Large-Scale, Longitudinal Empirical Studies in Middle Level Education Research

    Science.gov (United States)

    Mertens, Steven B.; Caskey, Micki M.; Flowers, Nancy

    2016-01-01

    This essay describes and discusses the ongoing need for large-scale, longitudinal, empirical research studies focused on middle grades education. After a statement of the problem and concerns, the essay describes and critiques several prior middle grades efforts and research studies. Recommendations for future research efforts to inform policy…

  14. 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

  15. 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.

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

    Science.gov (United States)

    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.

  17. 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…

  18. 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

  19. 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)

  20. 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

  1. Self-Efficacy as a Longitudinal Predictor of Perceived Cognitive Impairment in Individuals with Multiple Sclerosis

    Science.gov (United States)

    Hughes, Abbey J.; Beier, Meghan; Hartoonian, Narineh; Turner, Aaron P.; Amtmann, Dagmar; Ehde, Dawn M.

    2015-01-01

    Objective Self-efficacy plays an important role in symptom management and may be predictive of perceived cognitive impairment (PCI) for individuals with multiple sclerosis (MS). The primary aim of this study was to determine if self-efficacy longitudinally predicts two types of PCI in MS: general cognitive functioning and executive functioning. The secondary aim was to assess whether self-efficacy mediates the relationships between depression, fatigue, and PCI. Design Longitudinal analysis of self-report survey data collected over three years. Hierarchical regression analyses examined the relationship between self-efficacy and PCI, adjusting for depression and fatigue. Additional analyses tested self-efficacy as a mediator between depression, fatigue, and PCI. Setting Community-dwelling individuals with MS. Participants 233 individuals (age range 22-83 years) were recruited from a larger longitudinal survey study of 562 individuals with MS. Interventions Not applicable. Main Outcome Measures Primary outcome measures were the Applied Cognition General Concerns (ACGC) and Executive Function (ACEF) domains of the Quality of Life in Neurological Disorders (NeuroQoL) measures. Results Self-efficacy was significantly correlated with PCI at baseline (r = .40 to .53) and three years later (r = .36 to .44). In multivariate regression analyses, self-efficacy was a significant longitudinal predictor of PCI, both for general cognitive functioning (β = .20, p Self-efficacy partially mediated the relationships between depression, fatigue, and PCI. Conclusions Self-efficacy may influence how individuals with MS will perceive their cognitive functioning over time. Interventions that target self-efficacy, particularly early in the disease course, may lead to improvements in PCI, as well as improvements in fatigue and depression. PMID:25597915

  2. 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…

  3. Study on development of evaluation technique of in-situ tracer test in Horonobe Underground Research Laboratory project (Contract research)

    International Nuclear Information System (INIS)

    Yokota, Hideharu; Amano, Kenji; Maekawa, Keisuke; Kunimaru, Takanori; Naemura, Yumi; Ijiri, Yuji; Motoshima, Takayuki; Suzuki, Shunichi; Teshima, Kazufumi

    2013-06-01

    In the Horonobe Underground Research Laboratory Project, in-situ tracer tests are valuable and important as the investigations to obtain the mass transportation data of fractures in hostrock. However, it is difficult that the in-situ tests are executed under various conditions due to long test period and the tests results are evaluated about permeable heterogeneity in a fracture and/or scale effects. In this study, a number of tracer tests are simulated in a fictitious single plate fracture generated on computer. And the transport parameters are identified by fitting one- and two-dimensional models to the breakthrough curves obtained from the simulations in order to investigate the applicability of these models to the evaluation of in-situ tracer test. As a result, one-dimensional model yields larger longitudinal dispersion length than two-dimensional model in the both cases of homogeneous and heterogeneous hydraulic conductivity fields of the fictitious fracture. This is because that the effect of transverse dispersion has to be included in the longitudinal dispersion length parameter in the one-dimensional model. It is also found that the larger dipole ratio and the larger natural groundwater flow crossing the flow generated between two boreholes make the identified longitudinal dispersion length larger. And, the longitudinal dispersion length identified from a tracer test is smaller and/or larger than the macroscopic longitudinal dispersion length identified from whole fracture. It is clarified that these are occurred by shorter or longer distance between boreholes compare to the correlation length of geostatistical heterogeneity of fictitious fracture. (author)

  4. 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…

  5. 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...

  6. 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

  7. 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…

  8. Studies of Longitudinal Coupled-Bunch Instabilities in the LHC Injectors Chain

    CERN Document Server

    AUTHOR|(CDS)2087149; Migliorati, M

    Among several challenging objectives of the LHC Injectors Upgrade project, one aim is to double the beam intensity of the CERN Proton Synchrotron (PS) in order to achieve the integrated luminosity target of the High-Luminosity LHC project. A known limitation to reach the required high intensity is caused by the longitudinal coupled-bunch (CB) oscillations developing above the PS transition energy. The unwanted oscillations induce large bunch-to-bunch intensity variations not compatible with the specifications of the future LHC-type beams. In 2014 a new longitudinal kicker cavity has been installed, the Finemet cavity, as a part of the new digital coupled-bunch feedback (FB) system. The Finemet cavity allows with its large frequency bandwidth, to damp all the expected oscillation modes simultaneously. In the framework of this PhD study the impedance contribution of this equipment has been analyzed starting from the present knowledge of the machine impedance. A model of both the 10 MHz and the Finemet has been ...

  9. 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.

  10. 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...

  11. 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…

  12. 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…

  13. 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…

  14. 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…

  15. 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…

  16. The role of testosterone and estradiol in brain volume changes across adolescence: a longitudinal structural MRI study.

    Science.gov (United States)

    Herting, Megan M; Gautam, Prapti; Spielberg, Jeffrey M; Kan, Eric; Dahl, Ronald E; Sowell, Elizabeth R

    2014-11-01

    It has been postulated that pubertal hormones may drive some neuroanatomical changes during adolescence, and may do so differently in girls and boys. Here, we use growth curve modeling to directly assess how sex hormones [testosterone (T) and estradiol (E₂)] relate to changes in subcortical brain volumes utilizing a longitudinal design. 126 adolescents (63 girls), ages 10 to 14, were imaged and restudied ∼2 years later. We show, for the first time, that best-fit growth models are distinctly different when using hormones as compared to a physical proxy of pubertal maturation (Tanner Stage) or age, to predict brain development. Like Tanner Stage, T and E₂ predicted white matter and right amygdala growth across adolescence in both sexes, independent of age. Tanner Stage also explained decreases in both gray matter and caudate volumes, whereas E₂ explained only gray matter decreases and T explained only caudate volume decreases. No pubertal measures were related to hippocampus development. Although specificity was seen, sex hormones had strikingly similar relationships with white matter, gray matter, right amygdala, and bilateral caudate volumes, with larger changes in brain volume seen at early pubertal maturation (as indexed by lower hormone levels), followed by less robust, or even reversals in growth, by late puberty. These novel longitudinal findings on the relationship between hormones and brain volume change represent crucial first steps toward understanding which aspects of puberty influence neurodevelopment. Copyright © 2014 Wiley Periodicals, Inc.

  17. 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...

  18. 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.

  19. 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...

  20. 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.

  1. 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.

  2. 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.

  3. 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…

  4. 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.

  5. 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.

  6. 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…

  7. Transmission characteristics of Bessel-Gaussian vortex beams propagating along both longitudinal and transverse directions in a subway tunnel

    Science.gov (United States)

    Wang, Xiaohui; Song, Yingxiong

    2018-02-01

    By exploiting the non-Kolmogorov model and Rytov approximation theory, a propagation model of Bessel-Gaussian vortex beams (BGVB) propagating in a subway tunnel is derived. Based on the propagation model, a model of orbital angular momentum (OAM) mode probability distribution is established to evaluate the propagation performance when the beam propagates along both longitudinal and transverse directions in the subway tunnel. By numerical simulations and experimental verifications, the influences of the various parameters of BGVB and turbulence on the OAM mode probability distribution are evaluated, and the results of simulations are consistent with the experimental statistics. The results verify that the middle area of turbulence is more beneficial for the vortex beam propagation than the edge; when the BGVB propagates along the longitudinal direction in the subway tunnel, the effects of turbulence on the OAM mode probability distribution can be decreased by selecting a larger anisotropy parameter, smaller coherence length, larger non-Kolmogorov power spectrum coefficient, smaller topological charge number, deeper subway tunnel, lower train speed, and longer wavelength. When the BGVB propagates along the transverse direction, the influences can be also mitigated by adopting a larger topological charge number, less non-Kolmogorov power spectrum coefficient, smaller refractive structure index, shorter wavelength, and shorter propagation distance.

  8. 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.

  9. 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.

  10. 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....

  11. 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.

  12. 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.

  13. Editorial Commentary: The Larger Holes or Larger Number of Holes We Drill in the Coracoid, the Weaker the Coracoid Becomes.

    Science.gov (United States)

    Brady, Paul

    2016-06-01

    The larger holes or larger number of holes we drill in the coracoid, the weaker the coracoid becomes. Thus, minimizing bone holes (both size and number) is required to lower risk of coracoid process fracture, in patients in whom transosseous shoulder acromioclavicular joint reconstruction is indicated. A single 2.4-mm-diameter tunnel drilled through both the clavicle and the coracoid lowers the risk of fracture, but the risk cannot be entirely eliminated. Copyright © 2016 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

  14. 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…

  15. 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.

  16. 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

  17. 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.

  18. Inside the virtual casino: a prospective longitudinal study of actual Internet casino gambling.

    Science.gov (United States)

    Labrie, Richard A; Kaplan, Sara A; Laplante, Debi A; Nelson, Sarah E; Shaffer, Howard J

    2008-08-01

    Participation in Internet gambling is growing rapidly, as is concern about its possible effects on the public's health. This article reports the results of the first prospective longitudinal study of actual Internet casino gambling behaviour. Data include 2 years of recorded Internet betting activity by a cohort of gamblers who subscribed to an Internet gambling service during February 2005. We examined computer records of each transaction and transformed them into measures of gambling involvement. The sample included 4222 gamblers who played casino games. The median betting behaviour was to play casino games once every 2 weeks during a period of 9 months. Subscribers placed a median of 49 bets of euro4 each playing day. Subscribers lost a median of 5.5% of total monies wagered. We determined a group of heavily involved bettors whose activity exceeded that of 95% of the sample; these players bet every fifth day during 17.5 months. On each playing day, these most involved bettors placed a median of 188 bets of euro25. Their median percent of wagers lost, 2.5%, was smaller than that lost by the total sample. Our findings suggest that Internet casino betting behaviour results in modest costs for most players, while some, roughly 5%, have larger losses. The findings also show the need to consider time spent as a marker of disordered gambling. These findings provide the evidence to steer public health debates away from speculation and toward the creation of empirically-based strategies to protect the public health.

  19. 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.

  20. 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.

  1. 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

  2. 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

  3. 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…

  4. Child adiposity and maternal feeding practices: a longitudinal analysis.

    Science.gov (United States)

    Webber, Laura; Cooke, Lucy; Hill, Claire; Wardle, Jane

    2010-12-01

    Parental control has been hypothesized to cause weight gain in children by weakening self-regulatory processes. However, most studies that link control with weight have been cross-sectional, and therefore causation is uncertain. It remains possible that parental control is a response to child overweight rather than a cause. We investigated the direction of the association between parental feeding practices and children's adiposity in a longitudinal study. Three subscales of the Child Feeding Questionnaire (CFQ) that measure "pressure," "restriction," and "monitoring" were completed by 213 mothers of 7-9-y-old children as part of the Physical Exercise and Appetite in CHildren Study (PEACHES) and repeated by 113 mothers 3 y later. Baseline and follow-up anthropometric measurements [body mass index (BMI); fat mass index (FMI), and waist circumference (WC)] were made by researchers when the children were aged 7-9 y and 10-11 y. Regression analyses showed no association between any of the CFQ scales at baseline and change in child adiposity. In contrast, higher child BMI at baseline predicted a smaller decrease in follow-up CFQ "monitoring" (P = 0.003) and a larger decrease in "pressure to eat" (P = 0.04) after baseline scores were controlled for. Similar results were observed for FMI and WC, although they did not reach significance for WC. There were no significant longitudinal associations between child adiposity and the CFQ "restriction" subscale. The results were more consistent with a "child-responsive" model whereby a mother's choice of feeding practice is influenced by her child's weight status rather than her feeding practices influencing the child's weight gain.

  5. 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

  6. 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...

  7. 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,…

  8. 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…

  9. 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.

  10. 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…

  11. 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

  12. 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

  13. 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

  14. 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...

  15. Smoking in Movies and Adolescent Smoking Initiation: A Longitudinal Study among Argentinian Adolescents

    Science.gov (United States)

    Mejia, Raul; Pérez, Adriana; Peña, Lorena; Kollath-Cattano, Christy; Morello, Paola; Braun, Sandra; Hardin, James W.; Thrasher, James F.; Sargent, James

    2016-01-01

    Objective To assess whether exposure to movie smoking is associated with cigarette smoking among Argentinian adolescents. Study design School-based longitudinal study involving 33 secondary schools in Argentina. The sample included 2502 never smokers (average age at entry =12.5y), 1,700 (67.9%) of whom completed follow-up surveys 17 months later. Exposure to the top 100 grossing films for each year between 2009 and 2013 was assessed by content-coding films for tobacco, and then asking adolescents whether they had seen each of 50 titles, randomly selected from the larger pool, then parsing exposure into tertiles. Logistic regression models estimated adjusted odds ratio (AOR) for the following transitions: non-susceptible to susceptible never smoker, never smoker to ever smoker, and never smoker to current smoking (last 30 days). Results At follow-up, 34.4% of non-susceptible never smokers became susceptible, 24.1% reported having tried smoking, and 9.6% were current smokers. Most exposure to movie smoking was from US-produced films (average 60.3 minutes compared with only 3.4 minutes from Argentine films). Higher exposure to smoking in movies was significantly associated with increased odds of becoming susceptible (AOR1st vs 3rd tertile = 1.77, 95% confidence interval 1.30–2.41), of trying smoking (AOR1st vs 3rd tertile = 1.54, 1.14–2.08), and marginally associated with current smoking (AOR1st vs 3rd tertile = 1.54, 0.99–2.40). Exposure to smoking in US- or Argentine-produced films had similar associations. Conclusion In Argentina, exposure to smoking in the movies predicted future smoking transitions among early adolescents, with most exposure coming from viewing US movies. PMID:28029343

  16. 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/.

  17. 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.

  18. 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.

  19. 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.

  20. 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...

  1. 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)

  2. "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…

  3. 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).…

  4. 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.

  5. 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.

  6. 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

  7. 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.

  8. C-reactive protein, APOE genotype and longitudinal cognitive change in an older population

    Science.gov (United States)

    Lima, Thomas A. S.; Adler, Amanda L.; Minett, Thais; Matthews, Fiona E.; Brayne, Carol; Marioni, Riccardo E.

    2014-01-01

    Background: circulating measures of inflammatory markers, such as C-reactive protein (CRP) have been associated with an increased risk of future cognitive decline. However, the nature of the relationship among the very old (>75 years) is unclear. Cross-sectional evidence suggests that elevated CRP may even be protective in this age group. This study examines these associations longitudinally. Methods: logistic regression was used to investigate the association between CRP and drop in cognitive performance (≥3 point change on the Mini-Mental State Examination) over a 4-year period in a population of 266 people, mean age 77 years. Results: increased levels of CRP were associated with a decreased risk of a drop in cognitive performance; however, this association was only seen in those without an APOE e4 allele [odds ratio of decline per unit increase in ln(CRP) 0.57, P = 0.04]. The magnitude of the finding remained consistent after adjustment for cardiovascular confounders (smoking, drinking, MI, stroke, diabetes, education, medication and blood pressure). For those with an e4 allele, the relationship with longitudinal cognitive decline was neither statistically significant nor in a consistent direction after controlling for acute inflammation. Conclusions: this study strengthens previous cross-sectional findings and shows elevated levels of CRP to be linked to a decreased risk of longitudinal cognitive decline in the very old. However, as with prior analyses, this was only observed in those not carrying an APOE e4 allele. Future work on larger APOE e4 allele carrying samples is required to determine the nature of the association in this population. PMID:24305621

  9. "Crazyghettosmart": A Case Study in Latina Identities

    Science.gov (United States)

    Vetter, Amy M.; Fairbanks, Colleen; Ariail, Mary

    2011-01-01

    Drawing from recent scholarship that examines schooling and the shifting terrain of youth identities, this study examines the identity constructions of Jessica, a Latina high school student. Our portrait of Jessica is part of a larger longitudinal study in which the middle and high school experiences of three Latinas, including Jessica, were…

  10. 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.

  11. 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.

  12. 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

  13. 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…

  14. 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…

  15. 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…

  16. 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…

  17. 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.

  18. [Research progress of larger flexion gap than extension gap in total knee arthroplasty].

    Science.gov (United States)

    Zhang, Weisong; Hao, Dingjun

    2017-05-01

    To summarize the progress of larger flexion gap than extension gap in total knee arthro-plasty (TKA). The domestic and foreign related literature about larger flexion gap than extension gap in TKA, and its impact factors, biomechanical and kinematic features, and clinical results were summarized. During TKA, to adjust the relations of flexion gap and extension gap is one of the key factors of successful operation. The biomechanical, kinematic, and clinical researches show that properly larger flexion gap than extension gap can improve both the postoperative knee range of motion and the satisfaction of patients, but does not affect the stability of the knee joint. However, there are also contrary findings. So adjustment of flexion gap and extension gap during TKA is still in dispute. Larger flexion gap than extension gap in TKA is a new joint space theory, and long-term clinical efficacy, operation skills, and related complications still need further study.

  19. 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 ...

  20. 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.

  1. 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.

  2. 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

  3. 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.

  4. 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…

  5. Prevalence, diagnosis, and management of diabetes mellitus among older Chinese: results from the China Health and Retirement Longitudinal Study.

    Science.gov (United States)

    Zhao, Yaohui; Crimmins, Eileen M; Hu, Peifeng; Shen, Yang; Smith, James P; Strauss, John; Wang, Yafeng; Zhang, Yuan

    2016-04-01

    To estimate prevalence of diabetes mellitus (DM), success in diagnosing, and methods of diabetes management in China. China Health and Retirement Longitudinal Study, a representative survey of the Chinese population at least 45 years old, is used to estimate diabetes and prediabetes prevalence, diagnosis, and treatment and their associations with residence, socioe-conomic, and demographic factors. Almost 60 % of middle-aged and elderly Chinese have prediabetes or diabetes in 2011-2012. DM prevalence increases with age, but the oldest group is least likely to be diagnosed. Prevalence is higher with higher body mass index, fasting cholesterol, and larger waist circumference. Higher prevalence is found in urban areas among residents with urban registration status (the Chinese administrative registration system or hukou), especially in coastal regions. Better rates of diagnosis, management, and education regarding diabetes are strongly associated with urban hukou, living in coastal areas, and in families with higher per capita expenditures, the appropriate economic resources measure in China. Diagnosis and management of diabetes is highly differential within China but recent efforts to improve health systems are succeeding in reducing undiagnosed disease. Current high prevalence of prediabetes suggests a more intensive effort is required in the future.

  6. Caffeine and alcohol intakes and overall nutrient adequacy are associated with longitudinal cognitive performance among U.S. adults.

    Science.gov (United States)

    Beydoun, May A; Gamaldo, Alyssa A; Beydoun, Hind A; Tanaka, Toshiko; Tucker, Katherine L; Talegawkar, Sameera A; Ferrucci, Luigi; Zonderman, Alan B

    2014-06-01

    Among modifiable lifestyle factors, diet may affect cognitive health. Cross-sectional and longitudinal associations may exist between dietary exposures [e.g., caffeine (mg/d), alcohol (g/d), and nutrient adequacy] and cognitive performance and change over time. This was a prospective cohort study, the Baltimore Longitudinal Study of Aging (n = 628-1305 persons depending on the cognitive outcome; ∼2 visits/person). Outcomes included 10 cognitive scores, spanning various domains of cognition. Caffeine and alcohol intakes and a nutrient adequacy score (NAS) were estimated from 7-d food diaries. Among key findings, caffeine intake was associated with better baseline global cognition among participants with a baseline age (Agebase) of ≥70 y. A higher NAS was associated with better baseline global cognition performance (overall, women, Agebase memory (immediate and delayed recall, Agebase ≥70 y), and slower rate of decline or faster improvement in the attention domain (women). For an Agebase of memory. In sum, patterns of diet and cognition associations indicate stratum-specific associations by sex and baseline age. The general observed trend was that of putative beneficial effects of caffeine intake and nutrient adequacy on domains of global cognition, verbal memory, and attention, and mixed effects of alcohol on domains of letter fluency, attention, and working memory. Further longitudinal studies conducted on larger samples of adults are needed to determine whether dietary factors individually or in combination are modifiers of cognitive trajectories among adults. © 2014 American Society for Nutrition.

  7. 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

  8. 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

  9. 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.

  10. 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.

  11. 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

  12. 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’.

  13. 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

  14. 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

  15. Lexical processing and distributional knowledge in sound-spelling mapping in a consistent orthography: A longitudinal study of reading and spelling in dyslexic and typically developing children.

    Science.gov (United States)

    Marinelli, Chiara Valeria; Cellini, Pamela; Zoccolotti, Pierluigi; Angelelli, Paola

    This study examined the ability to master lexical processing and use knowledge of the relative frequency of sound-spelling mappings in both reading and spelling. Twenty-four dyslexic and dysgraphic children and 86 typically developing readers were followed longitudinally in 3rd and 5th grades. Effects of word regularity, word frequency, and probability of sound-spelling mappings were examined in two experimental tasks: (a) spelling to dictation; and (b) orthographic judgment. Dyslexic children showed larger regularity and frequency effects than controls in both tasks. Sensitivity to distributional information of sound-spelling mappings was already detected by third grade, indicating early acquisition even in children with dyslexia. Although with notable differences, knowledge of the relative frequencies of sound-spelling mapping influenced both reading and spelling. Results are discussed in terms of their theoretical and empirical implications.

  16. 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

  17. 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.

  18. 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

  19. 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

  20. 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.)

  1. Longitudinal study of self-awakening and sleep/wake habits in adolescents

    Directory of Open Access Journals (Sweden)

    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

  2. Caregiver Self-Esteem as a Predictor of Patient Relationship Satisfaction: A Longitudinal Study.

    Science.gov (United States)

    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.

  3. 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.

  4. Temporal divergence of percent body fat and body mass index in pre-teenage children: the LOOK longitudinal study.

    Science.gov (United States)

    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

  5. Modelling variable dropout in randomised controlled trials with longitudinal outcomes: application to the MAGNETIC study.

    Science.gov (United States)

    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.

  6. 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.

  7. Parent and Child Cigarette Use: A Longitudinal, Multigenerational Study

    Science.gov (United States)

    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

  8. Excision and Patch Grafting of a Lateral Peyronie's Plaque-Utilizing a Longitudinal "Window" Approach.

    Science.gov (United States)

    Lue, Kathy; Emtage, Justin B; Martinez, Daniel R; Yang, Christopher; Carrion, Rafael

    2015-06-01

    longitudinal incision for PIEG is a feasible technique and may reduce the postoperative morbidity and dissection required with traditional circumcising incision with penile degloving. Larger comparative studies are necessary for further evaluation.

  9. The Effects of CLIL on Oral Comprehension and Production: A Longitudinal Case Study

    Science.gov (United States)

    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)…

  10. 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...

  11. 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.

  12. The Developmental Sequence of Social-Communicative Skills in Young Children with Autism: A Longitudinal Study

    Science.gov (United States)

    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…

  13. 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…

  14. 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...

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

    Science.gov (United States)

    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

  16. 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

  17. Gray matter concentration and effective connectivity changes in Alzheimer's disease: a longitudinal structural MRI study

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xingfeng; Coyle, Damien; Maguire, Liam; Watson, David R.; McGinnity, Thomas M. [University of Ulster, Intelligent Systems Research Centre, Magee Campus, Derry, Northern Ireland (United Kingdom)

    2011-10-15

    Understanding disease progression in Alzheimer's disease (AD) awaits the resolution of three fundamental questions: first, can we identify the location of ''seed'' regions where neuropathology is first present? Some studies have suggested the medial temporal lobe while others have suggested the hippocampus. Second, are there similar atrophy rates within affected regions in AD? Third, is there evidence of causality relationships between different affected regions in AD progression ?To address these questions, we conducted a longitudinal MRI study to investigate the gray matter (GM) changes in AD progression. Abnormal brain regions were localized by a standard voxel-based morphometry method, and the absolute atrophy rate in these regions was calculated using a robust regression method. Primary foci of atrophy were identified in the hippocampus and middle temporal gyrus (MTG). A model based upon the Granger causality approach was developed to investigate the cause-effect relationship over time between these regions based on GM concentration. Results show that in the earlier stages of AD, primary pathological foci are in the hippocampus and entorhinal cortex. Subsequently, atrophy appears to subsume the MTG. The causality results show that there is in fact little difference between AD and age-matched healthy control in terms of hippocampus atrophy, but there are larger differences in MTG, suggesting that local pathology in MTG is the predominant progressive abnormality during intermediate stages of AD development. (orig.)

  18. 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…

  19. 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)

  20. Frailty Change and Major Osteoporotic Fracture in the Elderly: Data from the Global Longitudinal Study of Osteoporosis in Women 3-Year Hamilton Cohort.

    Science.gov (United States)

    Li, Guowei; Papaioannou, Alexandra; Thabane, Lehana; Cheng, Ji; Adachi, Jonathan D

    2016-04-01

    Investigating the cumulative rate of deficits and the change of a frailty index (FI) chronologically is helpful in clinical and research settings in the elderly. However, limited evidence for the change of frailty before and after some nonfatal adverse health event such as a major osteoporotic fracture (MOF) is available. Data from the Global Longitudinal Study of Osteoporosis in Women 3-Year Hamilton cohort were used in this study. The changes of FI before and after onset of MOF were compared between the women with and without incident MOF. We also evaluated the relationship between risk of MOF, falls, and death and the change of FI and the absolute FI measures. There were 3985 women included in this study (mean age 69.4 years). The change of FI was significantly larger in the women with MOF than those without MOF at year 1 (0.085 versus 0.067, p = 0.036) and year 2 (0.080 versus 0.052, p = 0.042) post-baseline. The FI change was not significantly related with risk of MOF independently of age. However, the absolute FI measures were significantly associated with increased risk of MOF, falls, and death independently of age. In summary, the increase of the FI is significantly larger in the elderly women experiencing a MOF than their peer controls, indicating their worsening frailty and greater deficit accumulation after a MOF. Measures of the FI change may aid in the understanding of cumulative aging nature in the elderly and serve as an instrument for intervention planning and assessment. © 2015 American Society for Bone and Mineral Research.

  1. 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

  2. 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

  3. 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.

  4. 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.

  5. 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.

  6. 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

  7. Caffeine and Alcohol Intakes and Overall Nutrient Adequacy Are Associated with Longitudinal Cognitive Performance among U.S. Adults123

    Science.gov (United States)

    Beydoun, May A.; Gamaldo, Alyssa A.; Beydoun, Hind A.; Tanaka, Toshiko; Tucker, Katherine L.; Talegawkar, Sameera A.; Ferrucci, Luigi; Zonderman, Alan B.

    2014-01-01

    Among modifiable lifestyle factors, diet may affect cognitive health. Cross-sectional and longitudinal associations may exist between dietary exposures [e.g., caffeine (mg/d), alcohol (g/d), and nutrient adequacy] and cognitive performance and change over time. This was a prospective cohort study, the Baltimore Longitudinal Study of Aging (n = 628–1305 persons depending on the cognitive outcome; ∼2 visits/person). Outcomes included 10 cognitive scores, spanning various domains of cognition. Caffeine and alcohol intakes and a nutrient adequacy score (NAS) were estimated from 7-d food diaries. Among key findings, caffeine intake was associated with better baseline global cognition among participants with a baseline age (Agebase) of ≥70 y. A higher NAS was associated with better baseline global cognition performance (overall, women, Agebase memory (immediate and delayed recall, Agebase ≥70 y), and slower rate of decline or faster improvement in the attention domain (women). For an Agebase of memory. In sum, patterns of diet and cognition associations indicate stratum-specific associations by sex and baseline age. The general observed trend was that of putative beneficial effects of caffeine intake and nutrient adequacy on domains of global cognition, verbal memory, and attention, and mixed effects of alcohol on domains of letter fluency, attention, and working memory. Further longitudinal studies conducted on larger samples of adults are needed to determine whether dietary factors individually or in combination are modifiers of cognitive trajectories among adults. PMID:24744319

  8. 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

  9. 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…

  10. 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.

  11. 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)

  12. 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)

  13. 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....

  14. 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...

  15. 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...

  16. 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.

  17. 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.

  18. Changes in job strain and subsequent weight gain: a longitudinal study, based on the Danish Nurse Cohort.

    Science.gov (United States)

    Vesterlund, Gitte Kingo; Keller, Amélie Cléo; Heitmann, Berit Lilienthal

    2018-04-01

    Obesity as well as job strain is increasing, and job strain might contribute to weight gain. The objective of the current study was to examine associations between longitudinal alterations in the components of job strain and subsequent weight gain. The study was designed as a prospective cohort study with three questionnaire surveys enabling measurement of job-strain alterations over 6 years and subsequent measurements of weight gain after further 10 years of follow-up. ANCOVA and trend analyses were conducted. Job demands were measured as job busyness and speed, and control as amount of influence. Employed nurses in Denmark. We included a sub-sample of 6188 female nurses from the Danish Nurse Cohort, which consisted of the nurses who participated in surveys in 1993, 1999 and 2009. A linear trend in weight gain was seen in nurses who were often busy in 1999 between those who were rarely v. sometimes v. often busy in 1993 (P=0·03), with the largest weight gain in individuals with sustained high busyness in both years. Loss of influence between 1993 and 1999 was associated with larger subsequent weight gain than sustained high influence (P=0·003) or sustained low influence (P=0·02). For speed, no associations were found. Busyness, speed and influence differed in their relationship to subsequent weight gain. A decrease in job influence and a sustained burden of busyness were most strongly related to subsequent weight gain. Focus on job strain reduction and healthy diet is essential for public health.

  19. 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.

  20. 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

  1. 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…

  2. 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…

  3. 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,

  4. 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...

  5. 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...

  6. 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.

  7. 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...

  8. 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

  9. 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)

  10. 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

  11. 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.

  12. 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.

  13. Size selectivity of commercial (300 MC) and larger square mesh top ...

    African Journals Online (AJOL)

    In the present study, size selectivity of a commercial (300 MC) and a larger square mesh top panel (LSMTPC) codend for blue whiting (Micromesistius poutassou) were tested on a commercial trawl net in the international waters between Turkey and Greece. Trawling, performed during daylight was carried out at depths ...

  14. Patterns of species richness and the center of diversity in modern Indo-Pacific larger foraminifera.

    Science.gov (United States)

    Förderer, Meena; Rödder, Dennis; Langer, Martin R

    2018-05-29

    Symbiont-bearing Larger Benthic Foraminifera (LBF) are ubiquitous components of shallow tropical and subtropical environments and contribute substantially to carbonaceous reef and shelf sediments. Climate change is dramatically affecting carbonate producing organisms and threatens the diversity and structural integrity of coral reef ecosystems. Recent invertebrate and vertebrate surveys have identified the Coral Triangle as the planet's richest center of marine life delineating the region as a top priority for conservation. We compiled and analyzed extensive occurrence records for 68 validly recognized species of LBF from the Indian and Pacific Ocean, established individual range maps and applied Minimum Convex Polygon (MCP) and Species Distribution Model (SDM) methodologies to create the first ocean-wide species richness maps. SDM output was further used for visualizing latitudinal and longitudinal diversity gradients. Our findings provide strong support for assigning the tropical Central Indo-Pacific as the world's species-richest marine region with the Central Philippines emerging as the bullseye of LBF diversity. Sea surface temperature and nutrient content were identified as the most influential environmental constraints exerting control over the distribution of LBF. Our findings contribute to the completion of worldwide research on tropical marine biodiversity patterns and the identification of targeting centers for conservation efforts.

  15. Academic and Work-Related Burnout: A Longitudinal Study of Working Undergraduate University Business Students

    Science.gov (United States)

    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…

  16. Changing Stereotypes, Changing Grades: A Longitudinal Study of Stereotyping during a College Math Course

    Science.gov (United States)

    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'…

  17. Larger foraminifera of the Devil's Den and Blue Hole sinkholes, Florida

    Science.gov (United States)

    Cotton, Laura J.; Eder, Wolfgang; Floyd, James

    2018-03-01

    Shallow-water carbonate deposits are well-known from the Eocene of the US Gulf Coast and Caribbean. These deposits frequently contain abundant larger benthic foraminifera (LBF). However, whilst integrated stratigraphic studies have helped to refine the timing of LBF overturning events within the Tethys and Indo-Pacific regions with respect to global bio- and chemo-stratigraphic records, little recent work has been carried out in the Americas. The American LBF assemblages are distinctly different from those of Europe and the Indo-Pacific. It is therefore essential that the American bio-province is included in studies of LBF evolution, biodiversity and climate events to understand these processes on a global scale.Here we present the LBF ranges from two previously unpublished sections spanning 35 and 29 m of the upper Eocene Ocala limestone, as the early stages of a larger project addressing the taxonomy and biostratigraphy of the LBF of Florida. The study indicates that the lower member of the Ocala limestone may be Bartonian rather than Priabonian in age, with implications for the biostratigraphy of the region. In addition, the study highlights the need for multiple sites to assess the LBF assemblages and fully constrain ranges across Florida and the US Gulf and suggests potential LBF events for future integrated stratigraphic study.

  18. 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

  19. 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

  20. 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

  1. 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 ...

  2. Neuropathologic Studies of the Baltimore Longitudinal Study of Aging (BLSA)

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

  4. 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.

  5. Predicting Family Poverty and Other Disadvantaged Conditions for Child Rearing from Childhood Aggression and Social Withdrawal: A 30-Year Longitudinal Study

    Science.gov (United States)

    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…

  6. 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.

  7. 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

  8. 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.

  9. Specific Noncovalent Association of Chiral Large-Ring Hexaimines: Ion Mobility Mass Spectrometry and PM7 Study.

    Science.gov (United States)

    Troć, Anna; Gajewy, Jadwiga; Danikiewicz, Witold; Kwit, Marcin

    2016-09-05

    Ion mobility mass spectrometry and PM7 semiempirical calculations are effective complementary methods to study gas phase formation of noncovalent complexes from vaselike macrocycles. The specific association of large-ring chiral hexaimines, derived from enantiomerically pure trans-1,2-diaminocyclohexane and various isophthaldehydes, is driven mostly by CH-π and π-π stacking interactions. The isotrianglimine macrocycles are prone to form two types of aggregates: tail-to-tail and head-to-head (capsule) dimers. The stability of the tail-to-tail dimers is affected by the size and electronic properties of the substituents at the C-5 position of the aromatic ring. Electron-withdrawing groups stabilize the aggregate, whereas bulky or electron-donating groups destabilize the complexes. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Health-promoting factors in medical students and students of science, technology, engineering, and mathematics: design and baseline results of a comparative longitudinal study.

    Science.gov (United States)

    Kötter, Thomas; Tautphäus, Yannick; Scherer, Martin; Voltmer, Edgar

    2014-07-04

    The negative impact of medical school on students' general and mental health has often been reported. Compared to students of other subjects, or employed peers, medical students face an increased risk of developing depression, anxiety and burnout. While pathogenetic factors have been studied extensively, less is known about health-promoting factors for medical students' health. This longitudinal study aims to identify predictors for maintaining good general and mental health during medical education. We report here the design of the study and its baseline results. We initiated a prospective longitudinal cohort study at the University of Lübeck, Germany. Two consecutive classes of students, entering the university in 2011 and 2012, were recruited. Participants will be assessed annually for the duration of their course. We use validated psychometric instruments covering health outcomes (general and mental health) and personality traits, as well as self-developed, pre-tested items covering leisure activities and sociodemographic data. At baseline, compared to students of STEM (science, technology, engineering, and mathematics) subjects (n = 531; 60.8% response rate), a larger proportion of medical students (n = 350; 93.0% response rate) showed good general health (90.9% vs. 79.7%) and a similar proportion was in good mental health (88.3% vs. 86.3%). Medical students scored significantly higher in the personality traits of extraversion, conscientiousness, openness to experience and agreeableness. Neuroticism proved to be a statistically significant negative predictor for mental health in the logistic regression analyses. Satisfaction with life as a dimension of study-related behaviour and experience predicted general health at baseline. Physical activity was a statistically significant predictor for general health in medical students. Baseline data revealed that medical students reported better general and similar mental health compared to STEM students. The annual

  11. Smoking in Movies and Adolescent Smoking Initiation: A Longitudinal Study among Argentinian Adolescents.

    Science.gov (United States)

    Mejia, Raul; Pérez, Adriana; Peña, Lorena; Kollath-Cattano, Christy; Morello, Paola; Braun, Sandra; Hardin, James W; Thrasher, James F; Sargent, James D

    2017-01-01

    To assess whether exposure to movie smoking is associated with cigarette smoking among Argentinian adolescents. A school-based longitudinal study involving 33 secondary schools in Argentina was performed. The sample included 2502 never smokers (average age at entry = 12.5 years), 1700 (67.9%) of whom completed follow-up surveys 17 months later. Exposure to the top 100 highest-grossing films for each year between 2009 and 2013 was assessed by content-coding films for tobacco and then by asking adolescents whether they had seen each of 50 titles, randomly selected from the larger pool, then parsing exposure into tertiles. Logistic regression models estimated aOR for the following transitions: nonsusceptible to susceptible never smoker, never smoker to ever smoker, and never smoker to current smoking (last 30 days). At follow-up, 34.4% of nonsusceptible never smokers became susceptible, 24.1% reported having tried smoking, and 9.4% were current smokers. Most exposure to movie smoking was from US-produced films (average 60.3 minutes compared with only 3.4 minutes from Argentine films). Greater exposure to smoking in movies was significantly associated with increased odds of becoming susceptible (aOR first vs third tertile  1.77, 95% CI 1.30-2.41), of trying smoking (aOR first vs third tertile  1.54, 1.14-2.08), and marginally associated with current smoking (AOR first vs third tertile  1.54, 0.99-2.40). Exposure to smoking in US- or Argentine-produced films had similar associations. In Argentina, exposure to smoking in the movies predicted future smoking transitions among early adolescents, with most exposure coming from viewing US movies. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. The Relation between Mastery Goals and Intrinsic Motivation among University Students: A Longitudinal Study

    Science.gov (United States)

    Bieg, Sonja; Reindl, Marion; Dresel, Markus

    2017-01-01

    The present work broadens previous research on students' mastery goals and intrinsic motivation by exploring their reciprocal effects using a longitudinal approach. To this end, a study using four measurement points was conducted during 10 weeks of one semester. The sample comprised 1156 students enrolled in psychology courses at a medium-sized…

  13. Working Memory, Attention, and Mathematical Problem Solving: A Longitudinal Study of Elementary School Children

    Science.gov (United States)

    Swanson, H. Lee

    2011-01-01

    The role of working memory (WM) in children's growth in mathematical problem solving was examined in a longitudinal study of children (N = 127). A battery of tests was administered that assessed problem solving, achievement, WM, and cognitive processing (inhibition, speed, phonological coding) in Grade 1 children, with follow-up testing in Grades…

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

    Science.gov (United States)

    Jungert, Tomas

    2013-01-01

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

  15. Multiracial Children and Poverty: Evidence from the Early Childhood Longitudinal Study of Kindergartners

    Science.gov (United States)

    Bratter, Jenifer; Kimbro, Rachel Tolbert

    2013-01-01

    Despite the recent growth in multiracial children among American children, we know very little about their well-being. Using the Early Childhood Longitudinal Study, Kindergarten Class (N?=?17,706), we evaluated the likelihood of living in poverty and near poverty for multiracial and monoracial children. Most multiracial groups have poverty or near…

  16. "I Feel So Confused": A Longitudinal Study of Young Adolescents' Change in Self-Esteem

    Science.gov (United States)

    Booth, Margaret Zoller; Curran, Erin

    2010-01-01

    This paper investigates the growth of early adolescent self-esteem and self-concept as students progress through the middle level years (sixth through eighth grade). Based on mixed method longitudinal research conducted from 2004 to 2007, the study's findings suggest that this sample of 104 urban students' self-esteem changed most significantly…

  17. Prediction of the development of reading comprehension: a longitudinal study

    NARCIS (Netherlands)

    Verhoeven, L.T.W.; Leeuwe, J.F.J. van

    2008-01-01

    Specific effects of word decoding, vocabulary and listening comprehension abilities on the development of reading comprehension were longitudinally examined for a representative sample of 2143 Dutch children throughout the elementary school period. An attempt was made to test two theoretical

  18. Longitudinal interrelationships between frequent geographic relocation and personality development: results from the Amsterdam Growth and Health Longitudinal Study.

    Science.gov (United States)

    Lin, Kuan-Chia; Twisk, Jos W R; Rong, Jiin-Ru

    2011-04-01

    This study is part of the Amsterdam Growth and Health Longitudinal Study, which was undertaken to assess the long-term interrelationships between cumulative frequency of geographic relocation (CFGR) and the development of personality characteristics (i.e., Inadequacy, Rigidity, Social Inadequacy, Dominance, Self-sufficiency, Self-esteem, and Hostility). We found that participants who had more mobility experiences had lower consistency in their personality characteristics (the exception being Rigidity). Residential mobility from different life stages was positively associated with the continuity and change of Inadequacy and Dominance. In addition, young adults with higher Rigidity personality experienced fewer geographic moves during the transition from young adulthood to mid-life. Our study provides evidence that CFGR in different life stages may be associated with the development of personality characteristics from young adulthood to mid-life in different ways. Increased awareness of the potential interrelationships between frequent geographic relocation and personality development may have positive consequences for adult psychological health. © 2011 American Orthopsychiatric Association.

  19. Larger testes and higher inhibin B levels in Finnish than in Danish newborn boys

    DEFF Research Database (Denmark)

    Main, Katharina M; Toppari, Jorma; Suomi, Anne-Maarit

    2006-01-01

    CONTEXT: Recent studies showed that male reproductive health problems, such as cryptorchidism, hypospadias, testicular cancer, and low sperm quality, are more prevalent in Denmark than in Finland. OBJECTIVES: We hypothesized that, if fetal testicular dysgenesis contributed to these observations......, differences in gonadal development and the hypothalamus-pituitary-testis axis would already be detectable perinatally. Thus, we investigated healthy newborn boys in both countries. DESIGN: This was a prospective, longitudinal population-based study. SETTING: Two primary obstetric centers were included...

  20. Work-Team Implementation and Trajectories of Manufacturing Quality: A Longitudinal Field Study

    OpenAIRE

    Rajiv D. Banker; Joy M. Field; Kingshuk K. Sinha

    2001-01-01

    The study examines the sustainability of manufacturing quality improvements following the implementation of work teams on production lines. We posit that the impact on manufacturing quality, measured as the defect rate trajectory, is monotonically nonincreasing over time and may, more specifically, assume the shape of an inverted S-curve. Employing a longitudinal research design, we investigate four work teams over a 28-month period in a field setting. Each team corresponds to one of the four...

  1. Student perceptions of stress, coping, relationships, and academic civility: a longitudinal study.

    Science.gov (United States)

    Clark, Cynthia M; Nguyen, Danh T; Barbosa-Leiker, Celestina

    2014-01-01

    Academic incivility can increase student stress, jeopardize learning, damage relationships, and negatively impact the academic environment. This 3-year longitudinal study measured a cohort of prelicensure nursing students' progressive perceptions of stress, coping, student-student and faculty-student relationships, and levels of academic civility. While civility scores remained mild to moderately high overall, there was a slightly declining trend over the 3-year period. Perceived stressors and coping strategies and ways to improve academic civility are identified and discussed.

  2. Real-world effects of using a phone while driving on lateral and longitudinal control of vehicles.

    Science.gov (United States)

    Dozza, Marco; Flannagan, Carol A C; Sayer, James R

    2015-12-01

    Technologies able to augment human communication, such as smartphones, are increasingly present during all daily activities. Their use while driving, in particular, is of great potential concern, because of the high risk that distraction poses during this activity. Current countermeasures to distraction from phone use are considerably different across countries and not always widely accepted/adopted by the drivers. This study utilized naturalistic driving data collected from 108 drivers in the Integrated Vehicle-Based Safety Systems (IVBSS) program in 2009 and 2010 to assess the extent to which using a phone changes lateral or longitudinal control of a vehicle. The IVBSS study included drivers from three age groups: 20–30 (younger), 40–50 (middle-aged), and 60–70 (older). Results from this study show that younger drivers are more likely to use a phone while driving than older and middle-aged drivers. Furthermore, younger drivers exhibited smaller safety margins while using a phone. Nevertheless, younger drivers did not experience more severe lateral/longitudinal threats than older and middle-aged drivers, probably because of faster reaction times. While manipulating the phone (i.e., dialing, texting), drivers exhibited larger lateral safety margins and experienced less severe lateral threats than while conversing on the phone. Finally, longitudinal threats were more critical soon after phone interaction, suggesting that drivers terminate phone interactions when driving becomes more demanding. These findings suggest that drivers are aware of the potential negative effect of phone use on their safety. This awareness guides their decision to engage/disengage in phone use and to increase safety margins (self-regulation). This compensatory behavior may be a natural countermeasure to distraction that is hard to measure in controlled studies. Practical Applications: Intelligent systems able to amplify this natural compensatory behavior may become a widely accepted

  3. Cohort Profile: Footprints in Time, the Australian Longitudinal Study of Indigenous Children.

    Science.gov (United States)

    Thurber, Katherine A; Banks, Emily; Banwell, Cathy

    2015-06-01

    Indigenous Australians experience profound levels of disadvantage in health, living standards, life expectancy, education and employment, particularly in comparison with non-Indigenous Australians. Very little information is available about the healthy development of Australian Indigenous children; the Longitudinal Study of Indigenous Children (LSIC) is designed to fill this knowledge gap.This dataset provides an opportunity to follow the development of up to 1759 Indigenous children. LSIC conducts annual face-to-face interviews with children (aged 0.5-2 and 3.5-5 years at baseline in 2008) and their caregivers. This represents between 5% and 10% of the total population of Indigenous children in these age groups, including families of varied socioeconomic and cultural backgrounds. Study topics include: the physical, social and emotional well-being of children and their caregivers; language; culture; parenting; and early childhood education.LSIC is a shared resource, formed in partnership with communities; its data are readily accessible through the Australian Government Department of Social Services (see http://dss.gov.au/lsic for data and access arrangements). As one of very few longitudinal studies of Indigenous children, and the only national one, LSIC will enable an understanding of Indigenous children from a wide range of environments and cultures. Findings from LSIC form part of a growing infrastructure from which to understand Indigenous child health. © The Author 2014. Published by Oxford University Press on behalf of the International Epidemiological Association.

  4. In vivo longitudinal MRI and behavioral studies in experimental spinal cord injury.

    Science.gov (United States)

    Sundberg, Laura M; Herrera, Juan J; Narayana, Ponnada A

    2010-10-01

    Comprehensive in vivo longitudinal studies that include multi-modal magnetic resonance imaging (MRI) and a battery of behavioral assays to assess functional outcome were performed at multiple time points up to 56 days post-traumatic spinal cord injury (SCI) in rodents. The MRI studies included high-resolution structural imaging for lesion volumetry, and diffusion tensor imaging (DTI) for probing the white matter integrity. The behavioral assays included open-field locomotion, grid walking, inclined plane, computerized activity box performance, and von Frey filament tests. Additionally, end-point histology was assessed for correlation with both the MRI and behavioral data. The temporal patterns of the lesions were documented on structural MRI. DTI studies showed significant changes in white matter that is proximal to the injury epicenter and persisted to day 56. White matter in regions up to 1 cm away from the injury epicenter that appeared normal on conventional MRI also exhibited changes that were indicative of tissue damage, suggesting that DTI is a more sensitive measure of the evolving injury. Correlations between DTI and histology after SCI could not be firmly established, suggesting that injury causes complex pathological changes in multiple tissue components that affect the DTI measures. Histological evidence confirmed a significant decrease in myelin and oligodendrocyte presence 56 days post-SCI. Multiple assays to evaluate aspects of functional recovery correlated with histology and DTI measures, suggesting that damage to specific white matter tracts can be assessed and tracked longitudinally after SCI.

  5. 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

  6. Children’s understanding of scientific concepts : Combining a micro-developmental approach with a longitudinal study

    NARCIS (Netherlands)

    van der Steen, Steffie

    2015-01-01

    This paper shows that the social (teacher) and material environment (task) play an active part in children's learning process and cannot be viewed as a separate, outside-based influence on cognitive development. We illustrate this using a longitudinal study on children's understanding of scientific

  7. Can Language Attitudes Be Improved? A Longitudinal Study of Immigrant Students in Catalonia (Spain)

    Science.gov (United States)

    Ianos, Maria-Adelina; Huguet, Ángel; Janés, Judit; Lapresta, Cecilio

    2017-01-01

    This study explores changes in attitudes towards Catalan, Spanish, and English over a 2-year period, on the part of secondary education students of immigrant origin residing in Catalonia. It aims to provide new data by adopting a longitudinal design and by focusing on the immigrant population, which has raised new challenges for the Catalan…

  8. How Fast Do Students Forget What They Learn in Consumer Behavior? A Longitudinal Study

    Science.gov (United States)

    Bacon, Donald R.; Stewart, Kim A.

    2006-01-01

    The retention curve for knowledge acquired in a consumer behavior course is explored in a longitudinal study, tracking individual students from 8 to 101 weeks following course completion. Rasch measurement is used to link tests and to achieve intervally scaled measures of knowledge. The findings indicate that most of the knowledge gained in the…

  9. Pilot study protocol to inform a future longitudinal study of ageing using linked administrative data: Healthy AGeing in Scotland (HAGIS).

    Science.gov (United States)

    Douglas, Elaine; Rutherford, Alasdair; Bell, David

    2018-01-10

    Population ageing is a welcome testament to improvements in the social, economic and health circumstances over the life course. However, these successes necessitate that we understand more about the pathways of ageing to plan and cost our health and social care services, to support our ageing population to live healthier for longer and to make adequate provisions for retirement. Longitudinal studies of ageing facilitate such understanding in many countries around the world. Scotland presently does not have a longitudinal study of ageing, despite dramatic increases to its ageing population and its poor health record. Healthy AGeing in Scotland (HAGIS) constitutes the launch of Scotland's first comprehensive longitudinal study of ageing. A sample of 1000 people aged 50+ years will be invited to take part in a household social survey. The innovative sampling procedure used administrative data to identify eligible households. Anonymised survey responses will be linked to administrative data. Ethics approval was obtained from the host institution for the study design and from the Public Benefits and Privacy Panel for administrative data linkage. Anonymised survey data will be deposited with the UK Data Service. A subset of survey data, harmonised with other global ageing studies, will be available via the Gateway to Global Aging platform. These data will enable powerful cross-country comparisons across the social, economic and health domains that will be relevant for national and international research.Research publications from the HAGIS team will be disseminated through journal articles and national and international conferences. The findings will support current and future research and policy debate on ageing populations. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  10. 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.

  11. Social Activity and Cognitive Functioning Over Time: A Coordinated Analysis of Four Longitudinal Studies

    Directory of Open Access Journals (Sweden)

    Cassandra L. Brown

    2012-01-01

    Full Text Available Social activity is typically viewed as part of an engaged lifestyle that may help mitigate the deleterious effects of advanced age on cognitive function. As such, social activity has been examined in relation to cognitive abilities later in life. However, longitudinal evidence for this hypothesis thus far remains inconclusive. The current study sought to clarify the relationship between social activity and cognitive function over time using a coordinated data analysis approach across four longitudinal studies. A series of multilevel growth models with social activity included as a covariate is presented. Four domains of cognitive function were assessed: reasoning, memory, fluency, and semantic knowledge. Results suggest that baseline social activity is related to some, but not all, cognitive functions. Baseline social activity levels failed to predict rate of decline in most cognitive abilities. Changes in social activity were not consistently associated with cognitive functioning. Our findings do not provide consistent evidence that changes in social activity correspond to immediate benefits in cognitive functioning, except perhaps for verbal fluency.

  12. In vivo longitudinal micro-CT study of bent long limb bones in rat offspring.

    Science.gov (United States)

    De Schaepdrijver, Luc; Delille, Peter; Geys, Helena; Boehringer-Shahidi, Christian; Vanhove, Christian

    2014-07-01

    Micro-computed X-ray tomography (micro-CT) has been reported as a reliable method to assess ex vivo rat and rabbit fetal skeletons in embryo-fetal developmental toxicity studies. Since micro-CT is a non-invasive imaging modality it has the potential for longitudinal, in vivo investigation of postnatal skeletal development. This is the first paper using micro-CT to assess the reversibility of drug-induced bent long bones in a longitudinal study from birth to early adulthood in rat offspring. Analysis of the scans obtained on postnatal Day 0, 7, 21 and 80 showed complete recovery or repair of the bent long limb bones (including the scapula) within the first 3 weeks. When assessing risk the ability to demonstrate recovery is highly advantageous when interpreting such transient skeletal change. In summary, in vivo micro-CT of small laboratory animals can aid in non-clinical safety assessment, particularly for specific mechanistic purposes or to address a particular concern in developmental biology. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. Gender differences in psychosocial functioning of adolescents with symptoms of anxiety and depression: longitudinal findings from the Nord-Trøndelag Health Study.

    Science.gov (United States)

    Derdikman-Eiron, Ruth; Indredavik, Marit S; Bakken, Inger Johanne; Bratberg, Grete H; Hjemdal, Odin; Colton, Matthew

    2012-11-01

    To explore longitudinally gender differences in the associations between psychosocial functioning, subjective well-being and self-esteem among adolescents with and without symptoms of anxiety and depression. Data were obtained from a major population-based Norwegian study, the Nord-Trøndelag Health Study, in which 1,092 boys and 1,262 girls (86% of all invited) completed an extensive self-report questionnaire at baseline (mean age 14.4 years) and at follow-up (mean age 18.4 years). Gender was a moderator variable in the associations between symptoms of anxiety and depression and impairment, meaning that boys' functioning was impaired to a larger extent than girls' functioning. A statistically significant interaction effect between gender and symptoms of anxiety and depression was found at follow-up in terms of subjective well-being (p self-esteem (p self-esteem than boys who had no symptoms at both time points. No similar differences were found among the girls. Previous and ongoing symptoms of anxiety and depression had more negative consequences for boys than for girls. These findings may contribute to improved assessment and intervention methods tailored differently for each gender.

  14. Longitudinal Study: Efficacy of Online Technology Tools for Instructional Use

    Science.gov (United States)

    Uenking, Michael D.

    2011-01-01

    Studies show that the student population (secondary and post secondary) is becoming increasingly more technologically savvy. Use of the internet, computers, MP3 players, and other technologies along with online gaming has increased tremendously amongst this population such that it is creating an apparent paradigm shift in the learning modalities of these students. Instructors and facilitators of learning can no longer rely solely on traditional lecture-based lesson formals. In order to achieve student academic success and satisfaction and to increase student retention, instructors must embrace various technology tools that are available and employ them in their lessons. A longitudinal study (January 2009-June 2010) has been performed that encompasses the use of several technology tools in an instructional setting. The study provides further evidence that students not only like the tools that are being used, but prefer that these tools be used to help supplement and enhance instruction.

  15. Larger foraminifera distribution on a mesotrophic carbonate shelf in SW Sulawesi (Indonesia)

    NARCIS (Netherlands)

    Renema, W.; Troelstra, S.R.

    2001-01-01

    Larger symbiont bearing foraminifera typically live in shallow tropical seas. In this study the fauna composition of patch reefs scattered over the Spermonde Shelf (SW Sulawesi, Indonesia), a mesotrophic carbonate shelf, is examined. The foraminiferal fauna of the Spermonde Shelf is characterised by

  16. Falls and fear of falling predict future falls and related injuries in ambulatory individuals with spinal cord injury: a longitudinal observational study.

    Science.gov (United States)

    Jørgensen, Vivien; Butler Forslund, Emelie; Opheim, Arve; Franzén, Erika; Wahman, Kerstin; Hultling, Claes; Seiger, Åke; Ståhle, Agneta; Stanghelle, Johan K; Roaldsen, Kirsti S

    2017-04-01

    What is the 1-year incidence of falls and injurious falls in a representative cohort of community-dwelling ambulatory individuals with chronic spinal cord injury? What are the predictors of recurrent falls (more than two/year) and injurious falls in this population? One-year longitudinal observational multi-centre study. A representative sample of 68 (of 73 included) community-dwelling ambulatory individuals with traumatic SCI attending regular follow-up programs at rehabilitation centres. Primary outcome measures were incidence and predictors of recurrent falls (more than two/year) and injurious falls reported every 2 weeks for 1year. A total of 48% of participants reported recurrent falls. Of the 272 reported falls, 41% were injurious. Serious injuries were experienced by 4% of participants, all of whom were women. Multivariate logistic regression analysis showed that recurrent falls in the previous year (OR=111, 95% CI=8.6 to 1425), fear of falling (OR=6.1, 95% CI=1.43 to 26) and longer time taken to walk 10m (OR=1.3, 95% CI=1.0 to 1.7) were predictors of recurrent falls. Fear of falling (OR=4.3, 95% CI=1.3 to 14) and recurrent falls in the previous year (OR=4.2, 95% CI=1.2 to 14) were predictors of injurious falls. Ambulatory individuals have a high risk of falling and of fall-related injuries. Fall history, fear of falling and walking speed could predict recurrent falls and injurious falls. Further studies with larger samples are needed to validate these findings. [Jørgensen V, Butler Forslund E, Opheim A, Franzén E, Wahman K, Hultling C, Seiger Å, Ståhle A, Stanghelle JK, Roaldsen KS (2017) Falls and fear of falling predict future falls and related injuries in ambulatory individuals with spinal cord injury: a longitudinal observational study. Journal of Physiotherapy 63: 108-113]. Copyright © 2017 Australian Physiotherapy Association. Published by Elsevier B.V. All rights reserved.

  17. Psychological predictors of eco-driving: A longitudinal study

    OpenAIRE

    Lauper Elisabeth; Moser Stephanie; Fischer Maja; Matthies Ellen; Kaufmann-Hayoz Ruth

    2015-01-01

    Eco-driving has well-known positive effects on fuel economy and greenhouse-gas emissions. Moreover, eco-driving reduces road-traffic noise, which is a serious threat to the health and well-being of many people. We investigated the psychological predictors of the adoption of eco-driving from the perspective of road-traffic noise abatement. The data came from 890 car drivers who participated in a longitudinal survey over four months. Specifically, we tested the effects of the intention to preve...

  18. Longitudinal study of computerized cardiotocography in early fetal growth restriction

    NARCIS (Netherlands)

    Wolf, H.; Arabin, B.; Lees, Christoph C.; Oepkes, D.; Prefumo, Federico; Thilaganathan, B.; Todros, T.; Visser, G.H.A.; Bilardo, Caterina M.; Derks, J. B.; Diemert, A.; Duvekot, Johannes J.; Ferrazzi, E.; Frusca, T.; Hecher, K.; Marlow, N.; Martinelli, P.; Ostermayer, E.; Papageorghiou, Aris T.; Scheepers, Hubertina C. J.; Schlembach, D.; Schneider, K. T M; Valcamonico, A.; van Wassenaer-Leemhuis, A.; Ganzevoort, W.; Aktas, Ayse; Borgione, Silvia; Brezinka, Christoph; Calvert, Sandra; Chaoui, Rabih; Cornette, Jerome M J; Diehl, Thilo; van Eyck, Jim; Fratelli, Nicola; van Haastert, Inge Lot; Johnson, Samantha; Lobmaier, Silvia; Lopriore, Enrico; Mansi, Giuseppina; Missfelder-Lobos, Hannah; Martelli, Paola; Maso, Gianpaolo; Maurer-Fellbaum, Ute; Van Charante, Nico Mensing; De Tollenaer, Susanne Mulder; Moore, Tamanna; Napolitano, Raffaele; Oberto, Manuela; Ogge, Giovanna; van der Post, Joris Am; Preston, Lucy; Raimondi, Francesco; Reiss, Irwin K M; Rigano, Serena; Schuit, Ewoud; Skabar, Aldo; Spaanderman, Marc E.; Weisglas-Kuperus, Nynke; Zimmermann, Andrea

    2017-01-01

    Objectives: To explore whether, in early fetal growth restriction (FGR), the longitudinal pattern of fetal heart rate (FHR) short-term variation (STV) can be used to identify imminent fetal distress and whether abnormalities of FHR recordings are associated with 2-year infant outcome. Methods: The

  19. Predictors of Reading Skills for Kindergartners and First Grade Students in Spanish: A Longitudinal Study

    Science.gov (United States)

    Kim, Young-Suk; Pallante, Daniel

    2012-01-01

    This study investigated predictors of word reading and reading comprehension skills using longitudinal data from Spanish-speaking kindergartners (N = 163) and first grade students (N = 305) from high SES families in Chile. Individual differences in letter-naming fluency and phonemic segmentation fluency, but not vocabulary, were positive…

  20. Recruiting and Retaining an Ethnically Diverse Sample of Older Adults in a Longitudinal Intervention Study

    Science.gov (United States)

    Austin-Wells, Vonnette; McDougall, Graham J.; Becker, Heather

    2006-01-01

    This paper describes strategies developed to recruit and retain an ethnically diverse sample in a longitudinal intervention of 246 participants in the SeniorWISE study. The ethnic and socioeconomic differences of these participants necessitated the use of different methods of effectively communicating with this population. Recruitment benefited…

  1. 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…

  2. 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

  3. 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.

  4. Plantar fascia thickness is longitudinally associated with retinopathy and renal dysfunction: a prospective study from adolescence to adulthood.

    Science.gov (United States)

    Benitez-Aguirre, Paul Z; Craig, Maria E; Jenkins, Alicia J; Gallego, Patricia H; Cusumano, Janine; Duffin, Anthony C; Hing, Stephen; Donaghue, Kim C

    2012-03-01

    The aim was to study the longitudinal relationship between plantar fascia thickness (PFT) as a measure of tissue glycation and microvascular (MV) complications in young persons with type 1 diabetes (T1DM). We conducted a prospective longitudinal cohort study of 152 (69 male) adolescents with T1DM who underwent repeated MV complications assessments and ultrasound measurements of PFT from baseline (1997-2002) until 2008. Retinopathy was assessed by 7-field stereoscopic fundal photography and nephropathy by albumin excretion rate (AER) from three timed overnight urine specimens. Longitudinal analysis was performed using generalized estimating equations (GEE). Median (interquartile range) age at baseline was 15.1 (13.4-16.8) years, and median follow-up was 8.3 (7.0-9.5) years, with 4 (3-6) visits per patient. Glycemic control improved from baseline to final visit [glycated hemoglobin (HbA1c) 8.5% to 8.0%, respectively; p = .004]. Prevalence of retinopathy increased from 20% to 51% (p 7.5 μg/min) increased from 26% to 29% (p = .2). A greater increase in PFT (mm/year) was associated with retinopathy at the final assessment (ΔPFT 1st vs. 2nd-4th quartiles, χ(2) = 9.87, p = .02). In multivariate GEE, greater PFT was longitudinally associated with retinopathy [odds ratio (OR) 4.6, 95% confidence interval (CI) 2.0-10.3] and early renal dysfunction (OR 3.2, CI 1.3-8.0) after adjusting for gender, blood pressure standard deviation scores, HbA1c, and total cholesterol. In young people with T1DM, PFT was longitudinally associated with retinopathy and early renal dysfunction, highlighting the importance of early glycemic control and supporting the role of metabolic memory in MV complications. Measurement of PFT by ultrasound offers a noninvasive estimate of glycemic burden and tissue glycation. © 2012 Diabetes Technology Society.

  5. Longitudinal muscle dysfunction in achalasia esophagus and its relevance.

    Science.gov (United States)

    Mittal, Ravinder K; Hong, Su Jin; Bhargava, Valmik

    2013-04-01

    Muscularis propria of the esophagus is organized into circular and longitudinal muscle layers. Goal of this review is to summarize the role of longitudinal muscle in physiology and pathophysiology of esophageal sensory and motor function. Simultaneous manometry and ultrasound imaging that measure circular and longitudinal muscle contraction respectively reveal that during peristalsis 2 layers of the esophagus contract in perfect synchrony. On the other hand, during transient relaxation of the lower esophageal sphincter (LES), longitudinal muscle contracts independently of circular muscle. Recent studies provide novel insights, i.e., longitudinal muscle contraction of the esophagus induces LES relaxation and possibly descending relaxation of the esophagus. In achalasia esophagus and other motility disorders there is discoordination between the 2 muscle layers. Longitudinal muscle contraction patterns are different in the recently described three types of achalasia identified by high-resolution manometry. Robust contraction of the longitudinal muscle in type II achalasia causes pan-esophageal pressurization and is the mechanism of whatever little esophageal emptying that take place in the absence of peristalsis and impaired LES relaxation. It may be that preserved longitudinal muscle contraction is also the reason for superior outcome to medical/surgical therapy in type II achalasia esophagus. Prolonged contractions of longitudinal muscles of the esophagus is a possible mechanism of heartburn and "angina like" pain seen in esophageal motility disorders and possibly achalasia esophagus. Novel techniques to record longitudinal muscle contraction are on the horizon. Neuro-pharmacologic control of circular and longitudinal muscles is different, which provides an important opportunity for the development of novel pharmacological therapies to treat sensory and motor disorders of the esophagus.

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

    Science.gov (United States)

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

    2017-09-01

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

  7. Euclidean distance and Kolmogorov-Smirnov analyses of multi-day auditory event-related potentials: a longitudinal stability study

    Science.gov (United States)

    Durato, M. V.; Albano, A. M.; Rapp, P. E.; Nawang, S. A.

    2015-06-01

    The validity of ERPs as indices of stable neurophysiological traits is partially dependent on their stability over time. Previous studies on ERP stability, however, have reported diverse stability estimates despite using the same component scoring methods. This present study explores a novel approach in investigating the longitudinal stability of average ERPs—that is, by treating the ERP waveform as a time series and then applying Euclidean Distance and Kolmogorov-Smirnov analyses to evaluate the similarity or dissimilarity between the ERP time series of different sessions or run pairs. Nonlinear dynamical analysis show that in the absence of a change in medical condition, the average ERPs of healthy human adults are highly longitudinally stable—as evaluated by both the Euclidean distance and the Kolmogorov-Smirnov test.

  8. Euclidean distance and Kolmogorov-Smirnov analyses of multi-day auditory event-related potentials: a longitudinal stability study

    International Nuclear Information System (INIS)

    Durato, M V; Nawang, S A; Albano, A M; Rapp, P E

    2015-01-01

    The validity of ERPs as indices of stable neurophysiological traits is partially dependent on their stability over time. Previous studies on ERP stability, however, have reported diverse stability estimates despite using the same component scoring methods. This present study explores a novel approach in investigating the longitudinal stability of average ERPs—that is, by treating the ERP waveform as a time series and then applying Euclidean Distance and Kolmogorov-Smirnov analyses to evaluate the similarity or dissimilarity between the ERP time series of different sessions or run pairs. Nonlinear dynamical analysis show that in the absence of a change in medical condition, the average ERPs of healthy human adults are highly longitudinally stable—as evaluated by both the Euclidean distance and the Kolmogorov-Smirnov test. (paper)

  9. Motivation Mediates the Perfectionism-Burnout Relationship: A Three-Wave Longitudinal Study With Junior Athletes.

    Science.gov (United States)

    Madigan, Daniel J; Stoeber, Joachim; Passfield, Louis

    2016-08-01

    Perfectionism in sports has been shown to predict longitudinal changes in athlete burnout. What mediates these changes over time, however, is still unclear. Adopting a self-determination theory perspective and using a three-wave longitudinal design, the current study examined perfectionistic strivings, perfectionistic concerns, autonomous motivation, controlled motivation, and athlete burnout in 141 junior athletes (mean age = 17.3 years) over 6 months of active training. When multilevel structural equation modeling was employed to test a mediational model, a differential pattern of between- and within-person relationships emerged. Whereas autonomous motivation mediated the negative relationship that perfectionistic strivings had with burnout at the between- and within-person level, controlled motivation mediated the positive relationship that perfectionistic concerns had with burnout at the between-persons level only. The present findings suggest that differences in autonomous and controlled motivation explain why perfectionism predicts changes in athlete burnout over time.

  10. 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.…

  11. The effect of longitudinal fluctuations in (3+1)D viscous hydrodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Pang, Long-Gang; Karpenko, Yuri [FIAS, Frankfurt (Germany); Petersen, Hannah [FIAS, Frankfurt (Germany); ITP, Goethe University, Frankfurt (Germany); GSI, Darmstadt (Germany); Huovinen, Pasi [ITP, University of Wroclaw (Poland); Wang, Xin-Nian [CCNU, Wuhan (China); LBNL, Berkeley (United States)

    2016-07-01

    The energy density fluctuations of the quark gluon plasma (QGP) in the transverse plane are studied in detail and found to be important to explain the high order harmonic flow v{sub n} at RHIC and LHC. However, the energy density fluctuations along longitudinal direction (space-time rapidity η{sub s}) have not been fully investigated yet, even though they should exist as well. Previous studies show that the longitudinal fluctuations strongly depend on the initial entropy deposition mechanisms. In this work AMPT initial conditions are used where HIJING introduces longitudinal fluctuations originating from the asymmetry between forward and backward going participants, string length fluctuations and finite number of partons at different collision energies. The longitudinal fluctuations have been found to be responsible for the de-correlation of anisotropic flow and twist of event planes along rapidity. We study the effect of longitudinal fluctuations on the QGP expansion in both transverse and longitudinal direction within CLVisc, a (3+1)D viscous hydrodynamic code parallelized on GPU using OpenCL, to check whether the anisotropic flow is affected by longitudinal fluctuations and to determine appropriate shear viscosity over entropy density coefficients η/s in comparison with experiments at RHIC and LHC.

  12. Confrontation Naming and Reading Abilities at Primary School: A Longitudinal Study

    Directory of Open Access Journals (Sweden)

    Chiara Luoni

    2015-01-01

    naming (i.e., the Boston Naming Test (BNT in a nonclinical sample of Italian primary school children was conducted (n=126, testing them at the end of each school year, to assess nonverbal intelligence, confrontation naming, and reading abilities. Results. Performance on the BNT emerged as a function of IQ and SES. Significant correlations between confrontation naming and reading abilities, especially comprehension, were found; BNT scores correlated better with reading fluency than with reading accuracy. Conclusions. The longitudinal data obtained in this study are discussed with regard to reading abilities, intelligence, age, gender, and socioeconomic status.

  13. Nucleon Spin Structure: Longitudinal and Transverse

    International Nuclear Information System (INIS)

    Chen, Jian-Ping

    2011-01-01

    Inclusive Deep-Inelastic Scattering (DIS) experiments have provided us with the most extensive information on the unpolarized and longitudinal polarized parton (quark and gluon) distributions in the nucleon. It has becoming clear that transverse spin and transverse momentum dependent distributions (TMDs) study are crucial for a more complete understanding of the nucleon structure and the dynamics of the strong interaction. The transverse spin structure and the TMDs are the subject of increasingly intense theoretical and experimental study recently. With a high luminosity electron beam facility, JLab has played a major role in the worldwide effort to study both the longitudinal and transverse spin structure. Highlights of recent results will be presented. With 12-GeV energy upgrade, JLab will provide the most precise measurements in the valence quark region to close a chapter in longitudinal spin study. JLab will also perform a multi-dimensional mapping of the transverse spin structure and TMDs in the valence quark region through Semi-Inclusive DIS (SIDIS) experiments, providing a 3-d partonic picture of the nucleon in momentum space and extracting the u and d quark tensor charges of the nucleon. The precision mapping of TMDs will also allow a detailed study of the quark orbital motion and its dynamics.

  14. Multiple and multidimensional transitions from trainee to trained doctor: a qualitative longitudinal study in the UK.

    Science.gov (United States)

    Gordon, Lisi; Jindal-Snape, Divya; Morrison, Jill; Muldoon, Janine; Needham, Gillian; Siebert, Sabina; Rees, Charlotte

    2017-12-01

    To explore trainee doctors' experiences of the transition to trained doctor, we answer three questions: (1) What multiple and multidimensional transitions (MMTs) are experienced as participants move from trainee to trained doctor? (2) What facilitates and hinders doctors' successful transition experiences? (3) What is the impact of MMTs on trained doctors? A qualitative longitudinal study underpinned by MMT theory. Four training areas (health boards) in the UK. 20 doctors, 19 higher-stage trainees within 6 months of completing their postgraduate training and 1 staff grade, associate specialist or specialty doctor, were recruited to the 9-month longitudinal audio-diary (LAD) study. All completed an entrance interview, 18 completed LADs and 18 completed exit interviews. Data were analysed cross-sectionally and longitudinally using thematic Framework Analysis. Participants experienced a multiplicity of expected and unexpected, positive and negative work-related transitions (eg, new roles) and home-related transitions (eg, moving home) during their trainee-trained doctor transition. Factors facilitating or inhibiting successful transitions were identified at various levels: individual (eg, living arrangements), interpersonal (eg, presence of supportive relationships), systemic (eg, mentoring opportunities) and macro (eg, the curriculum provided by Medical Royal Colleges). Various impacts of transitions were also identified at each of these four levels: individual (eg, stress), interpersonal (eg, trainees' children spending more time in childcare), systemic (eg, spending less time with patients) and macro (eg, delayed start in trainees' new roles). Priority should be given to developing supportive relationships (both formal and informal) to help trainees transition into their trained doctor roles, as well as providing more opportunities for learning. Further longitudinal qualitative research is now needed with a longer study duration to explore transition journeys for

  15. The Children’s Attention Project: a community-based longitudinal study of children with ADHD and non-ADHD controls

    Directory of Open Access Journals (Sweden)

    Sciberras Emma

    2013-01-01

    Full Text Available Abstract Background Attention-Deficit/Hyperactivity Disorder (ADHD affects approximately 5% of children worldwide and results in significant impairments in daily functioning. Few community-ascertained samples of children with ADHD have been studied prospectively to identify factors associated with differential outcomes. The Children’s Attention Project is the first such study in Australia, examining the mental health, social, academic and quality of life outcomes for children with diagnostically-confirmed ADHD compared to non-ADHD controls. The study aims to map the course of ADHD symptoms over time and to identify risk and protective factors associated with differential outcomes. Methods/design The sample for this prospective longitudinal study is being recruited across 43 socio-economically diverse primary schools across Melbourne, Australia. All children in Grade 1, the second year of formal schooling (6–8 years, are screened for ADHD symptoms using independent parent and teacher reports on the Conners’ 3 ADHD index (~N = 5260. Children screening positive for ADHD by both parent and teacher report, and a matched sample (gender, school screening negative, are invited to participate in the longitudinal study. At baseline this involves parent completion of the NIMH Diagnostic Interview Schedule for Children IV (DISC-IV to confirm likely ADHD diagnostic status and identify other mental health difficulties, direct child assessments (cognitive, academic, language and executive functioning; height and weight and questionnaires for parents and teachers assessing outcomes, as well as a broad range of risk and protective factors (child, parent/family, teacher/school, and socio-economic factors. Families will be initially followed up for 3 years. Discussion This study is the first Australian longitudinal study of children with ADHD and one of the first community-based longitudinal studies of diagnostically confirmed children with ADHD. The

  16. The ELAStiC (Electronic Longitudinal Alcohol Study in Communities project

    Directory of Open Access Journals (Sweden)

    Ashley Akbari

    2017-04-01

    Our project will aim to provide evidence that informs the UK Government’s commitment to “radically reshape the approach to alcohol and reduce the number of people drinking to excess”, by working with existing longitudinal data collected in the UK to inform policy and practice.

  17. Comparison between smaller ruptured intracranial aneurysm and larger un-ruptured intracranial aneurysm: gene expression profile analysis.

    Science.gov (United States)

    Li, Hao; Li, Haowen; Yue, Haiyan; Wang, Wen; Yu, Lanbing; ShuoWang; Cao, Yong; Zhao, Jizong

    2017-07-01

    As it grows in size, an intracranial aneurysm (IA) is prone to rupture. In this study, we compared two extreme groups of IAs, ruptured IAs (RIAs) smaller than 10 mm and un-ruptured IAs (UIAs) larger than 10 mm, to investigate the genes involved in the facilitation and prevention of IA rupture. The aneurismal walls of 6 smaller saccular RIAs (size smaller than 10 mm), 6 larger saccular UIAs (size larger than 10 mm) and 12 paired control arteries were obtained during surgery. The transcription profiles of these samples were studied by microarray analysis. RT-qPCR was used to confirm the expression of the genes of interest. In addition, functional group analysis of the differentially expressed genes was performed. Between smaller RIAs and larger UIAs, 101 genes and 179 genes were significantly over-expressed, respectively. In addition, functional group analysis demonstrated that the up-regulated genes in smaller RIAs mainly participated in the cellular response to metal ions and inorganic substances, while most of the up-regulated genes in larger UIAs were involved in inflammation and extracellular matrix (ECM) organization. Moreover, compared with control arteries, inflammation was up-regulated and muscle-related biological processes were down-regulated in both smaller RIAs and larger UIAs. The genes involved in the cellular response to metal ions and inorganic substances may facilitate the rupture of IAs. In addition, the healing process, involving inflammation and ECM organization, may protect IAs from rupture.

  18. Changes in Domain Specific Self-Perception amongst Young People with Intellectual Disability: A Longitudinal Study

    Science.gov (United States)

    O'Byrne, Clara; Muldoon, Orla T.

    2018-01-01

    This study examines the changes that occur in multidimensional self-concept of adolescents with a diagnosis of intellectual disabilities, across gender and category of intellectual disability (borderline, mild, moderate) groups. A sample of 54 young people completed the Harter Self-Perception Profile. Using a three-wave longitudinal study…

  19. The Development of Case Studies as a Method within a Longitudinal Study of Special Educational Needs Provision in the Republic of Ireland

    Science.gov (United States)

    Rose, Richard; Shevlin, Michael

    2016-01-01

    When developing case studies within a longitudinal study of special educational needs provision within the Republic of Ireland, the authors were conscious of the critiques of the use of this approach within educational research. The difficulties associated with generalisation, challenges of ensuring trustworthiness and the possibilities of…

  20. Clinical management and burden of bipolar disorder: a multinational longitudinal study (WAVE-bd Study

    Directory of Open Access Journals (Sweden)

    Moreno-Manzanaro Miriam

    2011-04-01

    Full Text Available Abstract Background Studies in bipolar disorder (BD to date are limited in their ability to provide a whole-disease perspective - their scope has generally been confined to a single disease phase and/or a specific treatment. Moreover, most clinical trials have focused on the manic phase of disease, and not on depression, which is associated with the greatest disease burden. There are few longitudinal studies covering both types of patients with BD (I and II and the whole course of the disease, regardless of patients' symptomatology. Therefore, the Wide AmbispectiVE study of the clinical management and burden of Bipolar Disorder (WAVE-bd (NCT01062607 aims to provide reliable information on the management of patients with BD in daily clinical practice. It also seeks to determine factors influencing clinical outcomes and resource use in relation to the management of BD. Methods WAVE-bd is a multinational, multicentre, non-interventional, longitudinal study. Approximately 3000 patients diagnosed with BD type I or II with at least one mood event in the preceding 12 months were recruited at centres in Austria, Belgium, Brazil, France, Germany, Portugal, Romania, Turkey, Ukraine and Venezuela. Site selection methodology aimed to provide a balanced cross-section of patients cared for by different types of providers of medical aid (e.g. academic hospitals, private practices in each country. Target recruitment percentages were derived either from scientific publications or from expert panels in each participating country. The minimum follow-up period will be 12 months, with a maximum of 27 months, taking into account the retrospective and the prospective parts of the study. Data on demographics, diagnosis, medical history, clinical management, clinical and functional outcomes (CGI-BP and FAST scales, adherence to treatment (DAI-10 scale and Medication Possession Ratio, quality of life (EQ-5D scale, healthcare resources, and caregiver burden (BAS scale

  1. Asthma Control and Sputum Eosinophils: A Longitudinal Study in Daily Practice.

    Science.gov (United States)

    Demarche, Sophie F; Schleich, Florence N; Paulus, Virginie A; Henket, Monique A; Van Hees, Thierry J; Louis, Renaud E

    Longitudinal trials have suggested that asthma control may be influenced by fluctuations in eosinophilic inflammation. This association has however never been confirmed in daily practice. To investigate the relationship between asthma control and sputum eosinophils in clinical practice. A retrospective longitudinal study was conducted on 187 patients with asthma with at least 2 successful sputum inductions at our Asthma Clinic. Linear mixed models were used to assess the relationship between asthma control and individual changes in sputum eosinophils. Receiver-operating characteristic curves were constructed to define minimal important differences (MIDs) of sputum eosinophils associated with a change of at least 0.5 in Asthma Control Questionnaire (ACQ) score. Then, a validation cohort of 79 patients with asthma was recruited to reassess this relationship and the accuracy of the MID values. A multivariate analysis showed that asthma control was independently associated with individual fluctuations in sputum eosinophil count (P eosinophilic asthma, we calculated a minimal important decrease of 4.3% in the percentage of sputum eosinophils (area under the curve [AUC], 0.69; P eosinophils and the accuracy of the MIDs of sputum eosinophils were confirmed in the validation cohort. At the individual level, asthma control was associated with fluctuations in sputum eosinophil count over time. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  2. What do medical students learn when they follow patients from hospital to community? A longitudinal qualitative study

    Directory of Open Access Journals (Sweden)

    Rukshini Puvanendran

    2012-07-01

    Full Text Available Context: Although longitudinal community-based care of patients provides opportunities for teaching patient centredness and chronic disease management, there is a paucity of literature assessing learning outcomes of these clerkships. This study examines learning outcomes among students participating in longitudinal community based follow-up of patients discharged from the hospital. Methods: The authors conducted a thematic analysis of 253 student narratives written by 44 third-year medical students reflecting on their longitudinal interactions with patients with chronic medical illnesses. The narratives were written over three periods: after acute hospital encounter, after a home visit and at the end of the 10-month follow-up. Analysis involved coding of theme content and counting of aggregate themes. Results: The most frequent theme was ‘chronic disease management’ (25% followed by ‘patient-centred care’ (22%, ‘health care systems’ (20.9%, ‘biomedical issues’ (19.7%, ‘community services’ (9.5% and ‘student's role conflict’ (2.3%. There was a shift in the relative frequency of the different themes, as students moved from hospital to community with their patients. Biomedical (44.3% and health systems (18.2% were the dominant themes following the acute hospitalization encounter. Chronic disease management (35.1% and patient centredness (31.8% were the dominant themes after the 10-month longitudinal follow-up. Conclusion: Longitudinal community-based interaction with patients resulted in learning about chronic disease management, patient centredness and health care systems over time. Students shifted from learning biomedical knowledge during the acute hospitalization, to focus on better understanding of long-term care and patient centredness, at the end of the module.

  3. Indicadores precoces da dislexia de desenvolvimento: um estudo longitudinal || Early indicators of dyslexia: a longitudinal study

    Directory of Open Access Journals (Sweden)

    Anabela Carvalho

    2017-12-01

    Full Text Available A dislexia do desenvolvimento é frequentemente diagnosticada quando os problemas na aprendizagem da leitura já afetaram negativamente outras áreas académicas e até o bem-estar emocional. A pesquisa internacional aponta para a existência de alguns preditores desta perturbação da aprendizagem, permitindo uma intervenção atempada e preventiva. No entanto, as diferenças relativas ao código ortográfico do Português Europeu não nos permitem tirar ilações de estudos realizados noutros contextos linguísticos. Com este problema em mente, desenvolvemos um estudo longitudinal que pretende destacar os preditores da dislexia em crianças portuguesas. A investigação seguiu um plano longitudinal ao longo de três anos e os resultados obtidos junto de uma amostra de 200 crianças permitem identificar a existência de poder preditivo em duas variáveis: no conhecimento que a criança tem do nome das letras e no seu desempenho em tarefas de fluência verbal, mostrando a influência que os fatores relativos às dificuldades na aquisição do princípio alfabético e no acesso ao léxico terão na manifestação posterior de problemas na aquisição da leitura.

  4. The Heritability of Insomnia Progression during Childhood/Adolescence: Results from a Longitudinal Twin Study

    Science.gov (United States)

    Barclay, Nicola L.; Gehrman, Philip R.; Gregory, Alice M.; Eaves, Lindon J.; Silberg, Judy L.

    2015-01-01

    Study Objectives: To determine prevalence and heritability of insomnia during middle/late childhood and adolescence; examine longitudinal associations in insomnia over time; and assess the extent to which genetic and environmental factors on insomnia remain stable, or whether new factors come into play, across this developmental period. Design: Longitudinal twin study. Setting: Academic medical center. Patients or Participants: There were 739 complete monozygotic twin pairs (52%) and 672 complete dizygotic twin pairs (48%) initially enrolled and were followed up at three additional time points (waves). Mode ages at each wave were 8, 10, 14, and 15 y (ages ranged from 8–18 y). Interventions: None. Measurements and Results: Clinical ratings of insomnia symptoms were assessed using the Child and Adolescent Psychiatric Assessment (CAPA) by trained clinicians, and rated according to Diagnostic and Statistical Manual of Mental Disorders, 3rd Edition—Revised criteria for presence of “clinically significant insomnia,” over four sequential waves. Insomnia symptoms were prevalent but significantly decreased across the four waves (ranging from 16.6% to 31.2%). “Clinically significant insomnia” was moderately heritable at all waves (h2 range = 14% to 38%), and the remaining source of variance was the nonshared environment. Multivariate models indicated that genetic influences at wave 1 contributed to insomnia at all subsequent waves, and that new genetic influences came into play at wave 2, which further contributed to stability of symptoms. Nonshared environmental influences were time-specific. Conclusion: Insomnia is prevalent in childhood and adolescence, and is moderately heritable. The progression of insomnia across this developmental time period is influenced by stable as well as new genetic factors that come into play at wave 2 (modal age 10 y). Molecular genetic studies should now identify genes related to insomnia progression during childhood and

  5. Base stock policies with degraded service to larger orders

    DEFF Research Database (Denmark)

    Du, Bisheng; Larsen, Christian

    We study an inventory system controlled by a base stock policy assuming a compound renewal demand process. We extend the base stock policy by incorporating rules for degrading the service of larger orders. Two specific rules are considered, denoted Postpone(q,t) and Split(q), respectively. The aim...... of using these rules is to achieve a given order fill rate of the regular orders (those of size less than or equal to the parameter q) having less inventory. We develop mathematical expressions for the performance measures order fill rate (of the regular orders) and average on-hand inventory level. Based...

  6. Investigating strengths and deficits to increase work engagement: A longitudinal study in the mining industry

    Directory of Open Access Journals (Sweden)

    Pule Mphahlele

    2018-02-01

    Full Text Available Orientation: The motivational process of the Job Demands-Resources (JD-R model indicates that job resources are the main predictors of work engagement. Previous research has found that the two job resources perceived organisational support (POS for strengths use and POS for deficit correction are also positively related to work engagement. However, the causal relationships between these variables have not been investigated longitudinally. Research purpose: To determine if POS for strengths use and POS for deficit correction are significant predictors of work engagement over time. Motivation for the study: In the literature, empirical evidence on the longitudinal relationships between work engagement and specific job resources, namely POS for strengths use and POS for deficit correction, is limited. Research design, approach and method: A longitudinal design was employed in this study. The first wave elicited a total of 376 responses, while the second wave had a total sample size of 79. A web-based survey was used to measure the constructs and to gather data at both points in time. Structural equation modelling was used to investigate the hypotheses. Main findings: The results indicated that both POS for strengths use and POS for deficit correction are positively related to work engagement in the short term. However, only POS for deficit correction significantly predicted work engagement over time. Practical and managerial implications: The results provide valuable insights to organisations by providing knowledge regarding which approach influences work engagement levels of their employees in the short and long term. Contribution or value-add: The study contributes to the limited research on what job resources predict work engagement over time.

  7. Excision and Patch Grafting of a Lateral Peyronie’s Plaque—Utilizing a Longitudinal “Window” Approach

    Science.gov (United States)

    Lue, Kathy; Emtage, Justin B; Martinez, Daniel R; Yang, Christopher; Carrion, Rafael

    2015-01-01

    unassisted erections and no recurrence of his curvature. Conclusion A lateral longitudinal incision for PIEG is a feasible technique and may reduce the postoperative morbidity and dissection required with traditional circumcising incision with penile degloving. Larger comparative studies are necessary for further evaluation. PMID:26185673

  8. Social support, social strain and inflammation: Evidence from a national longitudinal study of U.S. adults

    Science.gov (United States)

    Yang, Yang Claire; Schorpp, Kristen; Harris, Kathleen Mullan

    2014-01-01

    Social relationships have long been held to have powerful effects on health and survival, but it remains unclear whether such associations differ by function and domain of relationships over time and what biophysiological mechanisms underlie these links. This study addressed these gaps by examining the longitudinal associations of persistent relationship quality across a ten year span with a major indicator of immune function. Specifically, we examined how perceived social support and social strain from relationships with family, friends, and spouse at a prior point in time are associated with subsequent risks of inflammation, as assessed by overall inflammation burden comprised of five markers (C-reactive protein, interleukin-6, fibrinogen, E-selectin, and intracellular adhesion molecule-1) in a national longitudinal study of 647 adults from the Midlife Development in the United States (1995–2009). Results from multivariate regression analysis show that (1) support from family, friends, and spouse modestly protected against risks of inflammation; (2) family, friend, and total social strain substantially increased risks of inflammation; and (3) the negative associations of social strain were stronger than the positive associations of social support with inflammation. The findings highlight the importance of enriched conceptualizations, measures, and longitudinal analyses of both social and biological stress processes to elucidate the complex pathways linking social relationships to health and illness. PMID:24607674

  9. Social relationships and risk of dementia : a systematic review and meta-analysis of longitudinal cohort studies

    NARCIS (Netherlands)

    Kuiper, J.S.; Zuidersma, M.; Oude Voshaar, R.C.; Zuidema, S.U.; Heuvel, van den E.R.; Stolk, R.P.; Smidt, N.

    2015-01-01

    It is unclear to what extent poor social relationships are related to the development of dementia. A comprehensive systematic literature search identified 19 longitudinal cohort studies investigating the association between various social relationship factors and incident dementia in the general

  10. Social relationships and risk of dementia : A systematic review and meta-analysis of longitudinal cohort studies

    NARCIS (Netherlands)

    Kuiper, Jisca S.; Zuidersma, Marij; Oude Voshaar, Richard; Zuidema, Sytse; van den Heuvel, Edwin R.; Stolk, Ronald P.; Smidt, Nynke

    It is unclear to what extent poor social relationships are related to the development of dementia. A comprehensive systematic literature search identified 19 longitudinal cohort studies investigating the association between various social relationship factors and incident dementia in the general

  11. Longitudinal Examination of Aggression and Study Skills from Middle to High School: Implications for Dropout Prevention

    Science.gov (United States)

    Orpinas, Pamela; Raczynski, Katherine; Hsieh, Hsien-Lin; Nahapetyan, Lusine; Horne, Arthur M.

    2018-01-01

    Background: High school completion provides health and economic benefits. The purpose of this study is to describe dropout rates based on longitudinal trajectories of aggression and study skills using teacher ratings. Methods: The sample consisted of 620 randomly selected sixth graders. Every year from Grade 6 to 12, a teacher completed a…

  12. The Acquisition of Auxiliary Syntax: A Longitudinal Elicitation Study. Part 2: The Modals and Auxiliary DO

    Science.gov (United States)

    Rowland, Caroline F.; Theakston, Anna L.

    2009-01-01

    Purpose: The study of auxiliary acquisition is central to work on language development and has attracted theoretical work from both nativist and constructivist approaches. This study is part of a 2-part companion set that represents a unique attempt to trace the development of auxiliary syntax by using a longitudinal elicitation methodology. The…

  13. 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…

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

    Science.gov (United States)

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

    2016-04-06

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

  15. A Longitudinal Study of Accounting Students' Ethical Judgement Making Ability

    Science.gov (United States)

    Mohamed Saat, Maisarah; Porter, Stacey; Woodbine, Gordon

    2012-01-01

    This paper reports the effect of a moral education programme on the ethical judgement making ability of university students. The programme comprises two forms of intervention: a dedicated ethics course and subsequent practical training. A total of 113 accounting students from six Malaysian universities participated in a longitudinal study…

  16. Nitrates in drinking water and methemoglobin levels in pregnancy: a longitudinal study.

    Science.gov (United States)

    Manassaram, Deana M; Backer, Lorraine C; Messing, Rita; Fleming, Lora E; Luke, Barbara; Monteilh, Carolyn P

    2010-10-14

    Private water systems are more likely to have nitrate levels above the maximum contaminant level (MCL). Pregnant women are considered vulnerable to the effects of exposure to high levels of nitrates in drinking water due to their altered physiological states. The level of methemoglobin in the blood is the biomarker often used in research for assessing exposure to nitrates. The objective of this study was to assess methemoglobin levels and examine how various factors affected methemoglobin levels during pregnancy. We also examined whether differences in water use practices existed among pregnant women based on household drinking water source of private vs. public supply. A longitudinal study of 357 pregnant women was conducted. Longitudinal regression models were used to examine changes and predictors of the change in methemoglobin levels over the period of gestation. Pregnant women showed a decrease in methemoglobin levels with increasing gestation although nitrate intake from tap water among pregnant women around 36 weeks gestation (β = 0.046, p = 0.986). Four women had tap water nitrate levels above the MCL of 10 mg/L. At enrollment, a greater proportion of women who reported using water treatment devices were private wells users (66%) compared to public system users (46%) (p nitrate from water (p nitrate levels primarily below the MCL for drinking water were unlikely to show methemoglobin levels above the physiologic normal. Water use practices such as the use of treatment devices to remove nitrates varied according to water source and should be considered in the assessment of exposure to nitrates in future studies.

  17. Patient demands, lack of reciprocity, and burnout: a five-year longitudinal study about general practitioners.

    NARCIS (Netherlands)

    Bakker, A.B.; Schaufeli, W.B.; Sixma, H.J.; Bosveld, W.; Dierendonck, D. van

    2000-01-01

    This study among a sample of 207 general practitioners (GPs) uses a five-year longitudinal design to test a process model of burnout. On the basis of social exchange and equity theory, it is hypothesized and found that demanding patient contacts produce a lack of reciprocity in the GP-patient

  18. The Influence of Social Conditions Across the Life Course on the Human Gut Microbiota: A Pilot Project With the Wisconsin Longitudinal Study.

    Science.gov (United States)

    Herd, Pamela; Schaeffer, Nora Cate; DiLoreto, Kerryann; Jacques, Karen; Stevenson, John; Rey, Federico; Roan, Carol

    2017-12-15

    To test the feasibility of collecting and integrating data on the gut microbiome into one of the most comprehensive longitudinal studies of aging and health, the Wisconsin Longitudinal Study (WLS). The long-term goal of this integration is to clarify the contribution of social conditions in shaping the composition of the gut microbiota late in life. Research on the microbiome, which is considered to be of parallel importance to human health as the human genome, has been hindered by human studies with nonrandomly selected samples and with limited data on social conditions over the life course. No existing population-based longitudinal study had collected fecal specimens. Consequently, we created an in-person protocol to collect stool specimens from a subgroup of WLS participants. We collected 429 stool specimens, yielding a 74% response rate and one of the largest human samples to date. The addition of data on the gut microbiome to the WLS-and to other population based longitudinal studies of aging-is feasible, under the right conditions, and can generate innovative research on the relationship between social conditions and the gut microbiome. © The Author 2017. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  19. Cohort profile: the Motorik-Modul Longitudinal Study: physical fitness and physical activity as determinants of health development in German children and adolescents.

    Science.gov (United States)

    Wagner, Matthias O; Bös, Klaus; Jekauc, Darko; Karger, Claudia; Mewes, Nadine; Oberger, Jennifer; Reimers, Anne K; Schlenker, Lars; Worth, Annette; Woll, Alexander

    2014-10-01

    The Motorik-Modul (MoMo) Longitudinal Study aims to contribute to long-term improvement in the health of German children and adolescents by focusing on: (i) the development of physical fitness and physical activity (including period effects); (ii) the individual and physical/social environmental determinants of the development of physical fitness and physical activity; and (iii) the impact of physical fitness and physical activity on the development of physical and mental health. The MoMo Longitudinal Study began with a nationwide representative sample of 4529 children and adolescents who ranged in age from 4-17 years at the study baseline (2003-2006). The first survey wave of the MoMo Longitudinal Study was conducted between 2009 and 2012, with two subsequent survey waves to be conducted between 2014 and 2016 and 2018 and 2020, respectively. The MoMo Longitudinal Study includes a physical fitness test profile, a physical activity questionnaire, and subjective and objective measures of health from the German Health Interview and Examination Survey (KiGGS). Data access is provided on request (alexander.woll@kit.edu). For further information, including a complete list of publications please visit www.motorik-modul.de. Published by Oxford University Press on behalf of the International Epidemiological Association © The Author 2013; all rights reserved.

  20. Longitudinal study of iodine in toenails following IV administration of an iodine-containing contrast agent

    International Nuclear Information System (INIS)

    Spate, V.L.; Morris, J.S.; Nichols, T.A.; Baskett, C.K.; Mason, M.M.; Horsman, T.L.; McDougall, I.R.

    1998-01-01

    The literature on the relationship between diet and thyroid cancer (TC) risk and the higher incidence of TC among Asian immigrants to the US compared to second and third generation subgroups has prompted epidemiologists to hypothesize that increased levels of iodine consumption may be associated with TC risk, particularly among persons with a history of clinical or subclinical thyroid dysfunction. At the University of Missouri Research Reactor (MURR), we have applied epiboron neutron activation analysis to investigate human nails as a dietary monitor for iodine. Preliminary studies have indicated a positive correlation between dietary iodine intake and the concentration of iodine in toenails. However, these studies are confounded by high iodine levels (up to 30 ppm) in approximately 5% of the nails studied. We hypothesize that, in the subjects we have studied, the high iodine levels may be due to iodine-containing medications, in particular contrast-agents containing iopamidol. This paper will report on longitudinal studies using contrast agent subjects who where followed-up for almost two years compared to a longitudinal control and a population mean. Based on this study, we suggest that iodine-containing contrast agents contaminate nail samples via non-specific binding in the short term followed by incorporation in the nail as a result of absorption. (author)

  1. A longitudinal study on boys' and girls' career aspirations and interest in technology

    Science.gov (United States)

    Ardies, Jan; De Maeyer, Sven; Gijbels, David

    2015-09-01

    Background: More young people, boys and girls, are needed in technical studies and professions, as the relative number of students in technology-related studies has been decreasing in most industrialised countries. To overcome this decrease several countries implemented mandatory technology classes in the curriculum of secondary education. Purpose: This study has two goals: exploring the evolution of pupils' interest during the year(s) they attend the mandatory technology classes and exploring determining characteristics for differences in boys' and girls' attitude change over time. Sample: This study focuses on data gathered in the first and second grade of the first cycle in general secondary education in the North region of Belgium, Flanders. In a first stage we selected a good representation of geographically spread schools (n = 20), from which over 1300 students participated. Design and methods: A longitudinal study with eight measurement occasions spread over the course of two years is presented in order to capture the evolution of students' attitudes, making use of a multilevel growth model analysis. Results: The results show that students' interest in technology decreases over time, although at the end of each grade interest is increasing again. Boys' and girls' interest in technology also evolves a little different in the first cycle of secondary education. For career aspirations we didn't see any significant difference between boys and girls. Boys' and girls' aspirations decrease over time with a little increase by the end of the second grade. Students with a more technological curriculum also have more career aspirations in the field of technology than their peers with other curricula. Although students' perceptions about technology as a subject for boys and girls are largely stable. Conclusions: The evolution of students' attitude is far from linear, this strengthens us in the choice for a more complex analysis model and the choice for more measuring

  2. Criminal Profiles of Violent Juvenile Sex and Violent Juvenile Non-Sex Offenders: An Explorative Longitudinal Study

    Science.gov (United States)

    van Wijk, Anton Ph.; Mali, Bas R. F.; Bullens, Ruud A. R.; Vermeiren, Robert R.

    2007-01-01

    Few studies have longitudinally investigated the criminal profiles of violent juvenile sex and violent juvenile non-sex offenders. To make up for this lack, this study used police records of juveniles to determine the nature of the criminal profiles of violent sex offenders (n = 226) and violent non-sex offenders (n = 4,130). All offenders…

  3. A Longitudinal Study of Handwriting Skills in Pre-Schoolers: The Acquisition of Syllable Oriented Programming Strategies

    Science.gov (United States)

    Soler Vilageliu, Olga; Kandel, Sonia

    2012-01-01

    Previous studies have shown the relevance of the syllable as a programming unit in handwriting production, both in adults and elementary school children. This longitudinal study focuses on the acquisition of writing skills in a group of preschoolers. It examines how and when the syllable structure of the word starts regulating motor programming in…

  4. Children's Sympathy, Guilt, and Moral Reasoning in Helping, Cooperation, and Sharing: A 6-Year Longitudinal Study

    Science.gov (United States)

    Malti, Tina; Ongley, Sophia F.; Peplak, Joanna; Chaparro, Maria P.; Buchmann, Marlis; Zuffianò, Antonio; Cui, Lixian

    2016-01-01

    This study examined the role of sympathy, guilt, and moral reasoning in helping, cooperation, and sharing in a 6-year, three-wave longitudinal study involving 175 children (M[subscript age] 6.10, 9.18, and 12.18 years). Primary caregivers reported on children's helping and cooperation; sharing was assessed behaviorally. Child sympathy was assessed…

  5. Annual incidence rate of schizophrenia and schizophrenia spectrum disorders in a longitudinal population-based cohort study

    NARCIS (Netherlands)

    Sutterland, Arjen L.; Dieleman, Jeanne; Storosum, Jitschak G.; Voordouw, Bettie A. C.; Kroon, Jojanneke; Veldhuis, Joris; Denys, Damiaan A. J. P.; de Haan, Lieuwe; Sturkenboom, Miriam C. J. M.

    2013-01-01

    Longitudinal incidence studies of schizophrenia spectrum disorders (SSD) performed in mental health service organizations are prone to confounding factors not found in research performed in the general population. To estimate the incidence rates (IRs) over a 10-year period of SSD (broadly defined)

  6. 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

  7. Does the Glass Ceiling Exist? A Longitudinal Study of Women’s Progress on French Corporate Boards

    OpenAIRE

    Rey Dang; Duc Khuong Nguyen; Linh-Chi Vo

    2014-01-01

    In this article, we conduct a longitudinal study of women’s progress on French corporate boards of directors. We particularly focus on the extent to which women directors have circumvented the glass ceiling. Using a sample of SBF 120 companies over a 10

  8. Larger Bowl Size Increases the Amount of Cereal Children Request, Consume, and Waste

    NARCIS (Netherlands)

    Wansink, Brian; van Ittersum, Koert; Payne, Collin R.

    Objective To examine whether larger bowls bias children toward requesting more food from the adults who serve them. Study design Study 1 was a between-subject design involving 69 preschool-age children who were randomized to receive either a small (8 oz) or large (16 oz) cereal bowl and were asked

  9. 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.

  10. A Longitudinal Study of Maternal and Child Internalizing Symptoms Predicting Early Adolescent Emotional Eating.

    Science.gov (United States)

    Kidwell, Katherine M; Nelson, Timothy D; Nelson, Jennifer Mize; Espy, Kimberly Andrews

    2017-05-01

    To examine maternal and child internalizing symptoms as predictors of early adolescent emotional eating in a longitudinal framework spanning three critical developmental periods (preschool, elementary school, and early adolescence). Participants were 170 children recruited at preschool age for a longitudinal study. When children were 5.25 years, their mothers completed ratings of their own internalizing symptoms. During the spring of 4th grade, children completed measures of internalizing symptoms. In early adolescence, youth completed a measure of emotional eating. Maternal and child internalizing symptoms predicted adolescent emotional eating. The results indicated that child psychopathology moderated the association between maternal psychopathology (except for maternal anxiety) and early adolescent emotional eating. There was no evidence of mediation. Pediatric psychologists are encouraged to provide early screening of, and interventions for, maternal and child internalizing symptoms to prevent children's emotional eating. © The Author 2016. Published by Oxford University Press on behalf of the Society of Pediatric Psychology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

  11. Personality Predicts Mortality Risk: An Integrative Data Analysis of 15 International Longitudinal Studies.

    Science.gov (United States)

    Graham, Eileen K; Rutsohn, Joshua P; Turiano, Nicholas A; Bendayan, Rebecca; Batterham, Philip J; Gerstorf, Denis; Katz, Mindy J; Reynolds, Chandra A; Sharp, Emily S; Yoneda, Tomiko B; Bastarache, Emily D; Elleman, Lorien G; Zelinski, Elizabeth M; Johansson, Boo; Kuh, Diana; Barnes, Lisa L; Bennett, David A; Deeg, Dorly J H; Lipton, Richard B; Pedersen, Nancy L; Piccinin, Andrea M; Spiro, Avron; Muniz-Terrera, Graciela; Willis, Sherry L; Schaie, K Warner; Roan, Carol; Herd, Pamela; Hofer, Scott M; Mroczek, Daniel K

    2017-10-01

    This study examined the Big Five personality traits as predictors of mortality risk, and smoking as a mediator of that association. Replication was built into the fabric of our design: we used a Coordinated Analysis with 15 international datasets, representing 44,094 participants. We found that high neuroticism and low conscientiousness, extraversion, and agreeableness were consistent predictors of mortality across studies. Smoking had a small mediating effect for neuroticism. Country and baseline age explained variation in effects: studies with older baseline age showed a pattern of protective effects (HReffects for extraversion. This study demonstrated coordinated analysis as a powerful approach to enhance replicability and reproducibility, especially for aging-related longitudinal research.

  12. A longitudinal study of air contaminants in a newly built preschool. [Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Berglund, B. (Univ. of Stockholm, Sweden); Johansson, I.; Lindvall, T.

    1982-01-01

    The air quality in a newly built preschool was investigated in a longitudinal study. Typical air contaminants emanating from building materials were determined, their variation over time (0-18 months) was measured, and the influence of the ventilation system (81%-91% recirculation of return air) on contaminant concentrations was studied. Volatile organic compounds were sampled by adsorption on porous polymer, analysed by a GC/FID system, and identified by MS. A spatial build-up in concentration (ppb or ..mu..g/m/sup 3/ levels) is evident for all the organic compounds, as well as for CO/sub 2/, from the outdoor air, through the ventilation system, and through the rooms to the exhaust air. The longitudinal comparison over time shows that all the organic compounds decline in concentration mainly within the first 6 months of occupancy: 1-buttanol 4-14 times, toluene and pentanal + hexanal 2-4 times, while formaldehyde remained at a constant low level of 90 ppb (110 ..mu..g/m/sup 3/). It is difficult to believe that the problems of poor air quality in 100 preschools in Stockholm are caused by the organic compounds alone unless interactions occur. A preschool building needs to be gassed off during the first 6 months after its construction with no recirculation of return air allowed (outdoor air rate approx 4-5 ach). During at least 1-2 additional years, it is desired that the recirculation rate of return air is restricted, perhaps to 50%.

  13. Physical inactivity post-stroke: a 3-year longitudinal study.

    Science.gov (United States)

    Kunkel, Dorit; Fitton, Carolyn; Burnett, Malcolm; Ashburn, Ann

    2015-01-01

    To explore change in activity levels post-stroke. We measured activity levels using the activPAL™ in hospital and at 1, 2 and 3 years' post-stroke onset. Of the 74 participants (mean age 76 (SD 11), 39 men), 61 were assessed in hospital: 94% of time was spent in sitting/lying, 4% standing and 2% walking. Activity levels improved over time (complete cases n = 15); time spent sitting/lying decreased (p = 0.001); time spent standing, walking and number of steps increased (p = 0.001, p = 0.028 and p = 0.03, respectively). At year 3, 18% of time was spent in standing and 9% walking. Time spent upright correlated significantly with Barthel (r = 0.69 on admission, r = 0.68 on discharge, both p inactive for the majority of time. Time spent upright improved significantly by 1 year post-stroke; improvements slowed down thereafter. Poor activity levels correlated with physical and psychological measures. Larger studies are indicated to identify predictors of activity levels. Implications for Rehabilitation Activity levels (measured using activPAL™ activity monitor), increased significantly by 1 year post-stroke but improvements slowed down at 2 and 3 years. People with stroke were inactive for the majority of their day in hospital and in the community. Poor activity levels correlated with physical and psychological measures. Larger studies are indicated to identify the most important predictors of activity levels.

  14. Anxiety and its time courses during radiotherapy for non-metastatic breast cancer: A longitudinal study

    OpenAIRE

    Lewis, Florence; Merckaert, Isabelle; Liénard, Aurore; Libert, Yves; Etienne, Anne-Marie; Reynaert, Christine; Slachmuylder, Jean-Louis; Scalliet, Pierre; Van Houtte, Paul; COUCKE, Philippe; Salamon, Emile; Razavi, Darius

    2014-01-01

    Purpose: To our knowledge, no study has specifically assessed the time course of anxiety during radiotherapy (RT). The objective of this study was to assess anxiety time courses in patients with nonmetastatic breast cancer. Material and methods: This multicenter, descriptive longitudinal study included 213 consecutive patients with breast cancer who completed visual analog scales (VASs) assessing state anxiety before and after the RT simulation and the first and last five RT se...

  15. A longitudinal study of the impact of corporate social responsibility on firm performance in SMEs in Zambia

    NARCIS (Netherlands)

    Choongo, Progress

    2017-01-01

    The aim of this study is to investigate the impact of corporate social responsibility on firm performance using a longitudinal design in small and medium-sized enterprises (SMEs). The reported study was conducted in a Sub-Saharan African developing country, Zambia. Data were collected from 153

  16. Race, ideology, and the tea party: a longitudinal study.

    Directory of Open Access Journals (Sweden)

    Eric D Knowles

    Full Text Available The Tea Party movement, which rose to prominence in the United States after the election of President Barack Obama, provides an ideal context in which to examine the roles of racial concerns and ideology in politics. A three-wave longitudinal study tracked changes in White Americans' self-identification with the Tea Party, racial concerns (prejudice and racial identification, and ideologies (libertarianism and social conservatism over nine months. Latent Growth Modeling (LGM was used to evaluate potential causal relationships between Tea Party identification and these factors. Across time points, racial prejudice was indirectly associated with movement identification through Whites' assertions of national decline. Although initial levels of White identity did not predict change in Tea Party identification, initial levels of Tea Party identification predicted increases in White identity over the study period. Across the three assessments, support for the Tea Party fell among libertarians, but rose among social conservatives. Results are discussed in terms of legitimation theories of prejudice, the "racializing" power of political judgments, and the ideological dynamics of the Tea Party.

  17. Race, Ideology, and the Tea Party: A Longitudinal Study

    Science.gov (United States)

    Knowles, Eric D.; Lowery, Brian S.; Shulman, Elizabeth P.; Schaumberg, Rebecca L.

    2013-01-01

    The Tea Party movement, which rose to prominence in the United States after the election of President Barack Obama, provides an ideal context in which to examine the roles of racial concerns and ideology in politics. A three-wave longitudinal study tracked changes in White Americans’ self-identification with the Tea Party, racial concerns (prejudice and racial identification), and ideologies (libertarianism and social conservatism) over nine months. Latent Growth Modeling (LGM) was used to evaluate potential causal relationships between Tea Party identification and these factors. Across time points, racial prejudice was indirectly associated with movement identification through Whites’ assertions of national decline. Although initial levels of White identity did not predict change in Tea Party identification, initial levels of Tea Party identification predicted increases in White identity over the study period. Across the three assessments, support for the Tea Party fell among libertarians, but rose among social conservatives. Results are discussed in terms of legitimation theories of prejudice, the “racializing” power of political judgments, and the ideological dynamics of the Tea Party. PMID:23825630

  18. Hearing loss in the Royal Norwegian Navy: A longitudinal study.

    Science.gov (United States)

    Irgens-Hansen, Kaja; Baste, Valborg; Bråtveit, Magne; Lind, Ola; Koefoed, Vilhelm F; Moen, Bente E

    2016-01-01

    The aims of this longitudinal study were to investigate a significant threshold shift (STS) among personnel working on board the Royal Norwegian Navy's (RNoN) vessels between 2012 and 2014 and to identify possible determinants of STS. Hearing thresholds were measured by pure tone audiometry in two consecutive examinations (n = 226). STS was defined as an average change in hearing thresholds ≥ + 10 dB at 2,000 Hz, 3,000 Hz, and 4,000 Hz in either ear. Determinants of STS were assessed through a questionnaire. The incidence of STS was 23.0%. Significant determinants of STS were the number of episodes of temporary threshold shifts (TTS) in the Navy, exposure to continuous loud noise during work on board, and the number of gun shots (in the Navy, hunting, and sports). This study indicated a significant association between noise exposure on board Navy vessels and development of STS.

  19. Cultural Orientation Trajectories and Substance Use: Findings From a Longitudinal Study of Mexican-Origin Youth.

    Science.gov (United States)

    Cruz, Rick A; King, Kevin M; Cauce, Ana M; Conger, Rand D; Robins, Richard W

    2017-03-01

    Cultural adaptation may influence Latino youth substance use (SU) development, yet few longitudinal studies have examined cultural change over time and adolescent SU outcomes. Using longitudinal data collected annually across ages 10-16 from 674 Mexican-origin youth (50% female), the authors characterized cultural adaptation patterns for language use (English and Spanish use), values (American values and familism values), and identity (ethnic pride), and examined whether these cultural adaptation patterns were associated with differential SU risk. Youth with increasing bilingualism and high/stable family values had lower SU risk compared to youth who primarily spoke English and endorsed decreasing family values, respectively. Ethnic pride trajectories were not associated with SU. Findings highlight the importance of considering cultural change related to Latino youth SU. © 2016 The Authors. Child Development © 2016 Society for Research in Child Development, Inc.

  20. Longitudinal study of self-regulation, positive parenting, and adjustment problems among physically abused children

    Science.gov (United States)

    Kim, Jungmeen; Haskett, Mary E.; Longo, Gregory S.; Nice, Rachel

    2012-01-01

    Objective Research using normative and high-risk samples indicates a significant link between problems with self-regulation and child maladjustment. Nevertheless, little is known about the processes that may modify the link between self-regulation and maladjustment. This longitudinal study examined the joint contributions of child self-regulation and positive parenting behaviors to the development of externalizing and internalizing symptomatology spanning from preschool to 1st grade. Methods Data were collected on a total of 95 physically abused children (58% boys); our longitudinal analyses involved 43 children at Time 1 (preschool), 63 children at Time 2 (kindergarten), and 54 children at Time 3 (1st grade). Children's self-regulation was measured by parent report, and their externalizing and internalizing symptomatology was evaluated by teachers. Parents completed self-report measures of positive parenting. Results Our structural equation modeling analyses revealed positive parenting as a protective factor that attenuated the concurrent association between low self-regulation and externalizing symptomatology among physically abused children. Our findings regarding longitudinal changes in children's externalizing symptomatology supported the differential susceptibility hypothesis: Physically abused children who were at greater risk due to low levels of self-regulation were more susceptible to the beneficial effects of positive parenting, compared to those with high levels of self-regulation. Conclusions Findings suggest that although physical abuse presents formidable challenges that interfere with the development of adaptive self-regulation, positive parenting behaviors may ameliorate the detrimental effects of maladaptive self-regulation on the development of externalizing symptomatology. In addition, the positive and negative effects of caregiving behaviors were more prominent among physically abused children at great risk due to low self-regulation. Practice

  1. A Longitudinal Follow-Up Study of Affect in Children and Adults with Cornelia de Lange Syndrome

    Science.gov (United States)

    Nelson, Lisa; Moss, Jo; Oliver, Chris

    2014-01-01

    Studies of individuals with Cornelia de Lange syndrome (CdLS) have described changes in mood and behavior with age, although no empirical or longitudinal studies have been conducted. Caregivers of individuals with CdLS (N = 67), cri du chat syndrome (CdCS; N = 42), and Fragile X syndrome (FXS; N = 142) completed the Mood, Interest and Pleasure…

  2. Walkability and cardiometabolic risk factors: Cross-sectional and longitudinal associations from the Multi-Ethnic Study of Atherosclerosis.

    Science.gov (United States)

    Braun, Lindsay M; Rodríguez, Daniel A; Evenson, Kelly R; Hirsch, Jana A; Moore, Kari A; Diez Roux, Ana V

    2016-05-01

    We used data from 3227 older adults in the Multi-Ethnic Study of Atherosclerosis (2004-2012) to explore cross-sectional and longitudinal associations between walkability and cardiometabolic risk factors. In cross-sectional analyses, linear regression was used to estimate associations of Street Smart Walk Score® with glucose, triglycerides, HDL and LDL cholesterol, systolic and diastolic blood pressure, and waist circumference, while logistic regression was used to estimate associations with odds of metabolic syndrome. Econometric fixed effects models were used to estimate longitudinal associations of changes in walkability with changes in each risk factor among participants who moved residential locations between 2004 and 2012 (n=583). Most cross-sectional and longitudinal associations were small and statistically non-significant. We found limited evidence that higher walkability was cross-sectionally associated with lower blood pressure but that increases in walkability were associated with increases in triglycerides and blood pressure over time. Further research over longer time periods is needed to understand the potential for built environment interventions to improve cardiometabolic health. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Longitudinal cognitive decline in subcortical ischemic vascular disease--the LADIS Study

    DEFF Research Database (Denmark)

    Jokinen, Hanna; Kalska, Hely; Ylikoski, Raija

    2009-01-01

    BACKGROUND: Cross-sectional studies have indicated that subcortical ischemic vascular disease (SIVD), as defined according to imaging criteria, is associated with a specific clinical and cognitive profile. Much less is known about the long-term cognitive consequences of SIVD. The aim of the study...... was to investigate the longitudinal cognitive performance and incident dementia in subjects with and without SIVD in a sample of older adults with white matter lesions. METHODS: In the Leukoaraiosis and Disability (LADIS) study, 639 participants were examined with annual clinical and neuropsychological evaluations...... for 3 years. The subjects meeting the MRI criteria of SIVD at baseline were compared to the other subjects of the sample with linear mixed models. RESULTS: The overall level of cognitive performance over the follow-up period was inferior in multiple cognitive domains in SIVD subjects as compared...

  4. Identity Formation in Adulthood: A Longitudinal Study from Age 27 to 50

    Science.gov (United States)

    Fadjukoff, Päivi; Pulkkinen, Lea; Kokko, Katja

    2016-01-01

    ABSTRACT Longitudinal patterns of identity formation were analyzed in a representative cohort group of Finnish men and women born in 1959 across ages 27, 36, 42, and 50. The data were drawn from the Jyväskylä Longitudinal Study of Personality. Identity status (diffused, moratorium, foreclosed, achieved) from all four ages was available for 172 participants (54% females). Marcia’s Identity Status Interview used in this research included five domains: religious beliefs, political identity, occupational career, intimate relationships, and lifestyle. The findings indicated great variability in identity status across domains at each age level, and the identity trajectories fluctuated from age 27 to 50. The developmental trend from age 27 to 50 was moderately progressive (toward achievement) for the five domains and for overall identity, with the exception of a slightly regressive trend in male religious identity. Remaining stable in the same status category across the four measurements was rare and emerged only for diffusion in the ideological domains. Women generally outnumbered men in identity achievement at earlier ages, but the gender differences diminished in most domains at age 50, except in religious identity. In women overall diffusion decreased over time, but in men it remained at about 20% at ages 42 and 50. PMID:27019650

  5. Noise-induced hearing loss in a longitudinal study of Norwegian railway workers.

    Science.gov (United States)

    Lie, Arve; Skogstad, Marit; Johnsen, Torstein Seip; Engdahl, Bo; Tambs, Kristian

    2016-09-02

    The aim of this study was to analyse longitudinal data to assess the risk of noise-induced hearing loss (NIHL) in Norwegian railway workers. Longitudinal. A major Norwegian railway company. We examined data from the first and last audiograms for the period 1991-2014, from 9640 railway workers with varying occupational noise exposure and with an average observation period of 10 years. The course of hearing acuity in seven groups of railway workers (train drivers, conductors, bus drivers, traffic controllers, train maintenance workers, track maintenance workers and others) were compared with each other and with ISO standards (ISO 1999). The change in hearing threshold during the observation period was 2-3 dB in the 0.5-4 kHz range and 6-7 dB in the 3-6 kHz range adjusted for age and sex, for all occupational groups, which is slightly less than expected (8 dB) according to ISO 1999. The risk of NIHL in Norwegian railway workers during the period 1991-2014 has been negligible. 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/

  6. Leisure activities, education, and cognitive impairment in Chinese older adults: a population-based longitudinal study.

    Science.gov (United States)

    Zhu, Xinyi; Qiu, Chengxuan; Zeng, Yi; Li, Juan

    2017-05-01

    We examine the association between leisure-time activities and the risk of developing cognitive impairment among Chinese older people, and further investigate whether the association varies by educational level. This follow-up study included 6,586 participants (aged 79.5 ± 9.8 years, range 65-105 years, 51.7% female) of the Chinese Longitudinal Healthy Longevity Survey who were aged ≥65 years and were free of cognitive impairment in 2002. Incident cognitive impairment was defined at the 2005 or 2008/2009 survey following an education-based cut-off on the adapted Chinese version of Mini-Mental State Examination (MMSE). Participation in cognitive activities (e.g. reading) and non-exercise physical activity (e.g. housework) was assessed by a self-reported scale. Cox proportional hazard models were employed to examine the association of leisure activities with incident cognitive impairment while controlling for age, gender, education, occupation, residence, physical exercise, smoking, drinking, cardiovascular diseases and risk factors, negative well-being, and physical functioning, and baseline MMSE score. During a five-year follow-up, 1,448 participants developed incident cognitive impairment. Overall, a high level of participation in leisure activities was associated with a 41% decreased risk of cognitive impairment compared to low-level engagement in leisure activities after controlling for age, gender, education, and other confounders. Moreover, there was a significant interaction between leisure activity and educational level, such that the beneficial effect of leisure activities on cognitive function was larger in educated elderly than their uneducated counterparts, and only educated elderly benefited from cognitive activities. Late-life leisure activities protect against cognitive impairment among elderly Chinese people, and the protective effects are more profound for educated elderly.

  7. A longitudinal study in youth of heart rate variability at rest and in response to stress

    NARCIS (Netherlands)

    Li, Zhibin; Snieder, Harold; Su, Shaoyong; Ding, Xiuhua; Thayer, Julian F.; Treiber, Frank A.; Wang, Xiaoling

    Background: Few longitudinal studies have examined ethnic and sex differences, predictors and tracking stabilities of heart rate variability (HRV) at rest and in response to stress in youths and young adults. Methods: Two evaluations were performed approximately 1.5 years apart on 399 youths and

  8. Behavioral Inhibition as a Risk Factor for the Development of Childhood Anxiety Disorders: A Longitudinal Study

    NARCIS (Netherlands)

    P.E.H.M. Muris (Peter); A.M.L. van Brakel (Anna); A. Arntz (Arnoud); E. Schouten (Erik)

    2011-01-01

    textabstractThis longitudinal study examined the additive and interactive effects of behavioral inhibition and a wide range of other vulnerability factors in the development of anxiety problems in youths. A sample of 261 children, aged 5 to 8 years, 124 behaviorally inhibited and 137 control

  9. Chronic pain in multiple sclerosis: A 10-year longitudinal study.

    Science.gov (United States)

    Young, Jamie; Amatya, Bhasker; Galea, Mary P; Khan, Fary

    2017-07-01

    Pain is a common symptom associated with multiple sclerosis (MS), and has lasting effects on an individual's functional capacity and quality of life. A wide range of prevalence rates of pain (between 23% and 90%)have been reported in MS and this is mainly due to the methodological differences amongst the studies such as variability in patient sources, method of sampling and the definition of pain used. Chronic pain in MS, defined as pain lasting for greater than 3-6 months, can have a significant impact on their biopsychosocial health, including negative impact on activities of daily living, relationships and social participation. The long-term course of MS-related pain and its impact in an Australian cohort over a 7-year period has been investigated earlier. The aim of this longitudinal study was to describe the impact of chronic pain, pain-related disability and carer burden in persons with MS over a 10-year period. The aim of this longitudinal study was to describe the impact of chronic pain, pain-related disability and carer burden in persons with MS over a 10-year period. This was a prospective longitudinal study conducted at the Rehabilitation Department of Royal Melbourne Hospital (RMH), a tertiary referral hospital in Victoria and Australia. The source of participants was from the RMH MS database and contains detailed MS patient information including demographic data, diagnosis details (using McDonald's criteria), pain characteristics. Structured face-face interviews and validated measures were used, which include the visual analogue scale (VAS); chronic pain grade (CPG); the assessment of quality of life (AQoL) and the carer strain index (CSI). The mean age of the participants (n=70) was 55.3 years and majority (70%) were female. The mean age of the participants (n=70) was 55.3 years and majority (70%) were female. The findings show that over time (10 years), participants report having greater bilateral bodily pain and greater description of pain as 'worse

  10. Longitudinal wake field corrections in circular machines

    International Nuclear Information System (INIS)

    Symon, K.R.

    1996-01-01

    In computations of longitudinal particle motions in accelerators and storage rings, the fields produced by the interactions of the beam with the cavity in which it circulates are usually calculated by multiplying Fourier components of the beam current by the appropriate impedances. This procedure neglects the slow variation with time of the Fourier coefficients and of the beam revolution frequency. When there are cavity elements with decay times that are comparable with or larger than the time during which changes in the beam parameters occur, these changes can not be neglected. Corrections for this effect have been worked out in terms of the response functions of elements in the ring. The result is expressed as a correction to the impedance which depends on the way in which the beam parameters are changing. A method is presented for correcting a numerical simulation by keeping track of the steady state and transient terms in the response of a cavity

  11. Serum Calcium and the Risk of Incident Metabolic Syndrome: A 4.3-Year Retrospective Longitudinal Study

    Directory of Open Access Journals (Sweden)

    Jong Ha Baek

    2017-01-01

    Full Text Available BackgroundAn association between serum calcium level and risk of metabolic syndrome (MetS has been suggested in cross-sectional studies. This study aimed to evaluate the association between baseline serum calcium level and risk of incident MetS in a longitudinal study.MethodsWe conducted a retrospective longitudinal study of 12,706 participants without MetS who participated in a health screening program, had normal range serum calcium level at baseline (mean age, 51 years, and were followed up for 4.3 years (18,925 person-years. The risk of developing MetS was analyzed according to the baseline serum calcium levels.ResultsA total of 3,448 incident cases (27.1% of MetS developed during the follow-up period. The hazard ratio (HR for incident MetS did not increase with increasing tertile of serum calcium level in an age- and sex-matched model (P for trend=0.915. The HRs (95% confidence interval [CI] for incident MetS comparing the second and the third tertiles to the first tertile of baseline serum calcium level were 0.91 (95% CI, 0.84 to 0.99 and 0.85 (95% CI, 0.78 to 0.92 in a fully adjusted model, respectively (P for trend=0.001. A decreased risk of incident MetS in higher tertiles of serum calcium level was observed in subjects with central obesity and/or a metabolically unhealthy state at baseline.ConclusionThere was no positive correlation between baseline serum calcium levels and incident risk of MetS in this longitudinal study. There was an association between higher serum calcium levels and decreased incident MetS in individuals with central obesity or two components of MetS at baseline.

  12. A Longitudinal Study of Children's Theory of Mind, Self-Concept, and Gender-Role Orientation

    Science.gov (United States)

    Bosacki, Sandra Leanne

    2014-01-01

    This study investigated the longitudinal relations between theory of mind (ToM) understanding, self-perceptions, and perceptions of gender-role orientation in 28 school-aged children, (16 girls, 12 boys, aged 8-12 years). Theory of mind and perceptions of self were assessed at Time 1 (T1, M = 8 y 5 m) and two years later at Time 2 (T2, M = 10 y 4…

  13. Cognitive predictors and risk factors of PTSD following stillbirth: a short-term longitudinal study.

    OpenAIRE

    Horsch, A.; Jacobs, I.; McKenzie-McHarg, K.

    2015-01-01

    This short-term longitudinal study investigated cognitive predictors and risk factors of posttraumatic stress disorder (PTSD) in mothers following stillbirth. After a stillbirth at ≥ 24 weeks gestational age, 65 women completed structured clinical interviews and questionnaires assessing PTSD symptoms, cognitive predictors (appraisals, dysfunctional strategies), and risk factors (perceived social support, trauma history, obstetric history) at 3 and 6 months. PTSD symptoms decreased between 3 a...

  14. Stereotactic Radiosurgery with Neoadjuvant Embolization of Larger Arteriovenous Malformations: An Institutional Experience

    Directory of Open Access Journals (Sweden)

    Richard Dalyai

    2014-01-01

    Full Text Available Objective. This study investigates the safety and efficacy of a multimodality approach combining staged endovascular embolizations with subsequent SRS for the management of larger AVMs. Methods. Ninety-five patients with larger AVMs were treated with staged endovascular embolization followed by SRS between 1996 and 2011. Results. The median volume of AVM in this series was 28 cm3 and 47 patients (48% were Spetzler-Martin grade IV or V. Twenty-seven patients initially presented with hemorrhage. Sixty-one patients underwent multiple embolizations while a single SRS session was performed in 64 patients. The median follow-up after SRS session was 32 months (range 9–136 months. Overall procedural complications occurred in 14 patients. There were 13 minor neurologic complications and 1 major complication (due to embolization while four patients had posttreatment hemorrhage. Thirty-eight patients (40% were cured radiographically. The postradiosurgery actuarial rate of obliteration was 45% at 5 years, 56% at 7 years, and 63% at 10 years. In multivariate analysis, larger AVM size, deep venous drainage, and the increasing number of embolization/SRS sessions were negative predictors of obliteration. The number of embolizations correlated positively with the number of stereotactic radiosurgeries (P<0.005. Conclusions. Multimodality endovascular and radiosurgical approach is an efficacious treatment strategy for large AVM.

  15. Posterior longitudinal ligament status in cervical spine bilateral facet dislocations

    International Nuclear Information System (INIS)

    Carrino, John A.; Manton, Geoffrey L.; Morrison, William B.; Flanders, Adam E.; Vaccaro, Alex R.; Schweitzer, Mark E.

    2006-01-01

    It is generally accepted that cervical spine bilateral facet dislocation results in complete disruption of the posterior longitudinal ligament. The goal of this study was to evaluate the integrity of numerous spine-stabilizing structures by MRI, and to determine if any associations between injury patterns exist with respect to the posterior longitudinal ligament status. Retrospective case series. A retrospective review was performed of 30 cervical spine injury subjects with bilateral facet dislocation. Assessment of 1.5T MRI images was carried out for: intervertebral disc disruption, facet fracture, and ligamentous disruption. Statistical analyses were performed to evaluate for associations between various injury patterns and posterior longitudinal ligament status. The frequency of MRI abnormalities was: anterior longitudinal ligament disruption (26.7%), disc herniation or disruption (90%), posterior longitudinal ligament disruption (40%), facet fracture (63.3%) and disruption of the posterior column ligament complex (97%). There were no significant associations between injury to the posterior longitudinal ligament and other structures. Compared to surgical reports, MRI was accurate for determining the status for 24 of 26 ligaments (three of three anterior longitudinal ligament, seven of nine posterior longitudinal ligament, and 14 of 14 posterior column ligament complex) but generated false negatives in two instances (in both MRI showed an intact posterior longitudinal ligament that was torn at surgery). (orig.)

  16. Larger error signals in major depression are associated with better avoidance learning

    Directory of Open Access Journals (Sweden)

    James F eCavanagh

    2011-11-01

    Full Text Available The medial prefrontal cortex (mPFC is particularly reactive to signals of error, punishment, and conflict in the service of behavioral adaptation and it is consistently implicated in the etiology of Major Depressive Disorder (MDD. This association makes conceptual sense, given that MDD has been associated with hyper-reactivity in neural systems associated with punishment processing. Yet in practice, depression-related variance in measures of mPFC functioning often fails to relate to performance. For example, neuroelectric reflections of mediofrontal error signals are often found to be larger in MDD, but a deficit in post-error performance suggests that these error signals are not being used to rapidly adapt behavior. Thus, it remains unknown if depression-related variance in error signals reflects a meaningful alteration in the use of error or punishment information. However, larger mediofrontal error signals have also been related to another behavioral tendency: increased accuracy in avoidance learning. The integrity of this error-avoidance system remains untested in MDD. In this study, EEG was recorded as 21 symptomatic, drug-free participants with current or past MDD and 24 control participants performed a probabilistic reinforcement learning task. Depressed participants had larger mPFC EEG responses to error feedback than controls. The direct relationship between error signal amplitudes and avoidance learning accuracy was replicated. Crucially, this relationship was stronger in depressed participants for high conflict lose-lose situations, demonstrating a selective alteration of avoidance learning. This investigation provided evidence that larger error signal amplitudes in depression are associated with increased avoidance learning, identifying a candidate mechanistic model for hypersensitivity to negative outcomes in depression.

  17. A retrospective longitudinal study of animal and human rabies in Botswana 1989-2006

    OpenAIRE

    K.T. Moagabo; K.B. Monyame; E.K. Baipoledi; M. Letshwenyo; N. Mapitse; J.M.K. Hyera

    2009-01-01

    A longitudinal study of animal and human rabies covering 18 years from 1989 to 2006 was retrospectively conducted in order to highlight the epidemiological features and trends of the disease in Botswana. Over the 18-year period, a total of 4 306 brain specimens collected from various species of animals including human beings with clinical signs consistent with rabies were submitted to the National Veterinary Laboratory in Gaborone for confirmatory diagnosis. Of the samples submitted, 2 ...

  18. Parameter optimization method for longitudinal vibration absorber of ship shaft system

    Directory of Open Access Journals (Sweden)

    LIU Jinlin

    2017-05-01

    Full Text Available The longitudinal vibration of the ship shaft system is the one of the most important factors of hull stern vibration, and it can be effectively minimized by installing a longitudinal vibration absorber. In this way, the vibration and noise of ships can be brought under control. However, the parameters of longitudinal vibration absorbers have a great influence on the vibration characteristics of the shaft system. As such, a certain shafting testing platform was studied as the object on which a finite model was built, and the relationship between longitudinal stiffness and longitudinal vibration in the shaft system was analyzed in a straight alignment state. Furthermore, a longitudinal damping model of the shaft system was built in which the parameters of the vibration absorber were non-dimensionalized, the weight of the vibration absorber was set as a constant, and an optimizing algorithm was used to calculate the optimized stiffness and damping coefficient of the vibration absorber. Finally, the longitudinal vibration frequency response of the shafting testing platform before and after optimizing the parameters of the longitudinal vibration absorber were compared, and the results indicated that the longitudinal vibration of the shafting testing platform was decreased effectively, which suggests that it could provide a theoretical foundation for the parameter optimization of longitudinal vibration absorbers.

  19. Revisiting typhoid fever surveillance in low and middle income countries: lessons from systematic literature review of population-based longitudinal studies.

    Science.gov (United States)

    Mogasale, Vittal; Mogasale, Vijayalaxmi V; Ramani, Enusa; Lee, Jung Seok; Park, Ju Yeon; Lee, Kang Sung; Wierzba, Thomas F

    2016-01-29

    The control of typhoid fever being an important public health concern in low and middle income countries, improving typhoid surveillance will help in planning and implementing typhoid control activities such as deployment of new generation Vi conjugate typhoid vaccines. We conducted a systematic literature review of longitudinal population-based blood culture-confirmed typhoid fever studies from low and middle income countries published from 1(st) January 1990 to 31(st) December 2013. We quantitatively summarized typhoid fever incidence rates and qualitatively reviewed study methodology that could have influenced rate estimates. We used meta-analysis approach based on random effects model in summarizing the hospitalization rates. Twenty-two papers presented longitudinal population-based and blood culture-confirmed typhoid fever incidence estimates from 20 distinct sites in low and middle income countries. The reported incidence and hospitalizations rates were heterogeneous as well as the study methodology across the sites. We elucidated how the incidence rates were underestimated in published studies. We summarized six categories of under-estimation biases observed in these studies and presented potential solutions. Published longitudinal typhoid fever studies in low and middle income countries are geographically clustered and the methodology employed has a potential for underestimation. Future studies should account for these limitations.

  20. Longitudinal study of arteriogenesis with swept source optical coherence tomography and hyperspectral imaging

    Science.gov (United States)

    Poole, Kristin M.; Patil, Chetan A.; Nelson, Christopher E.; McCormack, Devin R.; Madonna, Megan C.; Duvall, Craig L.; Skala, Melissa C.

    2014-03-01

    Peripheral arterial disease (PAD) is an atherosclerotic disease of the extremities that leads to high rates of myocardial infarction and stroke, increased mortality, and reduced quality of life. PAD is especially prevalent in diabetic patients, and is commonly modeled by hind limb ischemia in mice to study collateral vessel development and test novel therapies. Current techniques used to assess recovery cannot obtain quantitative, physiological data non-invasively. Here, we have applied hyperspectral imaging and swept source optical coherence tomography (OCT) to study longitudinal changes in blood oxygenation and vascular morphology, respectively, intravitally in the diabetic mouse hind limb ischemia model. Additionally, recommended ranges for controlling physiological variability in blood oxygenation with respect to respiration rate and body core temperature were determined from a control animal experiment. In the longitudinal study with diabetic mice, hyperspectral imaging data revealed the dynamics of blood oxygenation recovery distally in the ischemic footpad. In diabetic mice, there is an early increase in oxygenation that is not sustained in the long term. Quantitative analysis of vascular morphology obtained from Hessian-filtered speckle variance OCT volumes revealed temporal dynamics in vascular density, total vessel length, and vessel diameter distribution in the adductor muscle of the ischemic limb. The combination of hyperspectral imaging and speckle variance OCT enabled acquisition of novel functional and morphological endpoints from individual animals, and provides a more robust platform for future preclinical evaluations of novel therapies for PAD.