Science.gov

Sample records for longitudinal practical measurement

  1. Financial austerity measures and their effects as perceived in daily practice by Italian nurses from 2010 to 2011: A longitudinal study.

    PubMed

    Palese, Alvisa; Vianello, Chiara; Cassone, Andrea; Polonia, Marta; Bortoluzzi, Guido

    2014-01-01

    Abstract Most western economies have in recent years been experiencing one of the longest and deepest economic recessions since the Great Depression. During a recession health-care expenditures are often among the first to be cut. However, what is occurring in daily practice from the point of view of care has not been documented to date. Describing the cost containment interventions undertaken and their effects as perceived in daily practice by Italian nurses was the aim of the study. A longitudinal study design was adopted from 2010 to 2011 involving 1,001 nurses each year. In the 2-year period taken into consideration, participants reported a significant increase in the number of cost containment measures adopted by their health-care organisations. The effects of these cost containment measures have been perceived by nurses especially in terms of (1) increased stress levels, (2) increased number of patients with social problems, and (3) increased nursing workloads. In addition, greater difficulties in finding clinical placement for nursing students and fewer resources devoted to nursing professional development were reported, indicating that some cost containment measures will have long-term effects. The economic crisis seems to affect mainly the most vulnerable groups of society. Innovative solutions for the need to reduce the costs of National Health Services do not seem to emerge from the findings.

  2. Longitudinal measurement invariance of psychosocial measures in physical activity research: An application to adolescent data.

    PubMed

    Roesch, Scott C; Norman, Greg J; Merz, Erin L; Sallis, James F; Patrick, Kevin

    2013-04-01

    The current study served as a practical and substantive guide to establishing longitudinal measurement invariance of psychosocial measures commonly used in adolescent physical activity (PA) research. Psychosocial data on an initial sample of 878 adolescents (ages 11 - 15) recruited through primary care providers were provided at baseline, 6, 12, and 24 months. The target measures included family support, peer support, decisional balance (pros, cons), self-efficacy, and behavioral strategies. Five of the six psychosocial measures exhibited strict longitudinal measurement invariance, with the 6th measure (self-efficacy) exhibiting strong longitudinal measurement invariance. These findings support the equivalence of these measures across time, and provide the foundation to substantively interpret group differences and associations involving these measures and PA.

  3. Longitudinal measurement invariance of psychosocial measures in physical activity research: An application to adolescent data

    PubMed Central

    Roesch, Scott C.; Norman, Greg J.; Merz, Erin L.; Sallis, James F.; Patrick, Kevin

    2012-01-01

    The current study served as a practical and substantive guide to establishing longitudinal measurement invariance of psychosocial measures commonly used in adolescent physical activity (PA) research. Psychosocial data on an initial sample of 878 adolescents (ages 11 – 15) recruited through primary care providers were provided at baseline, 6, 12, and 24 months. The target measures included family support, peer support, decisional balance (pros, cons), self-efficacy, and behavioral strategies. Five of the six psychosocial measures exhibited strict longitudinal measurement invariance, with the 6th measure (self-efficacy) exhibiting strong longitudinal measurement invariance. These findings support the equivalence of these measures across time, and provide the foundation to substantively interpret group differences and associations involving these measures and PA. PMID:23734064

  4. How many longitudinal covariate measurements are needed for risk prediction?

    PubMed

    Reinikainen, Jaakko; Karvanen, Juha; Tolonen, Hanna

    2016-01-01

    In epidemiologic follow-up studies, many key covariates, such as smoking, use of medication, blood pressure, and cholesterol, are time varying. Because of practical and financial limitations, time-varying covariates cannot be measured continuously, but only at certain prespecified time points. We study how the number of these longitudinal measurements can be chosen cost-efficiently by evaluating the usefulness of the measurements for risk prediction. The usefulness is addressed by measuring the improvement in model discrimination between models using different amounts of longitudinal information. We use simulated follow-up data and the data from the Finnish East-West study, a follow-up study, with eight longitudinal covariate measurements carried out between 1959 and 1999. In a simulation study, we show how the variability and the hazard ratio of a time-varying covariate are connected to the importance of remeasurements. In the East-West study, it is seen that for older people, the risk predictions obtained using only every other measurement are almost equivalent to the predictions obtained using all eight measurements. Decisions about the study design have significant effects on the costs. The cost-efficiency can be improved by applying the measures of model discrimination to data from previous studies and simulations. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Measurement Practice Guide

    ERIC Educational Resources Information Center

    College and Career Readiness and Success Center, 2014

    2014-01-01

    This discussion guide is part of a larger practice guide designed to help state education agencies (SEAs) define measurement goals, select college and career readiness measures and indicators designed to support those goals, and use the data gathered with those measures and indicators to make informed decisions about college and career readiness…

  6. Teacher Instructional Practices and Language Minority Students: A Longitudinal Model

    ERIC Educational Resources Information Center

    Chang, Mido

    2008-01-01

    The author examined the long-term effects of teacher instructional grouping practices on the early mathematical achievement of language minority students from various ethnic groups. The study used 3 longitudinal models. In the 1st model, English language learners (ELLs) displayed lower math performance than did English-only students in the…

  7. Longitudinal Adult Practical Problem-Solving: 1983, 1993, 2003

    ERIC Educational Resources Information Center

    Haught, Patricia A.; Walls, Richard T.

    2007-01-01

    A 20-year longitudinal study was conducted to examine adult performance on practical problems. Effects of independent variables of age, education, and administration time were assessed on solutions generated and quality points earned. Younger adults generated more solutions than other adults in 1983, 1993, and 2003. Both younger and middle adults…

  8. The estimate and measurement of longitudinal wave intensity

    NASA Astrophysics Data System (ADS)

    Ruisen, Ming

    1996-08-01

    Quasi-longitudinal waves are one type of structural waves, which are important at high frequencies. This paper studies the estimate theory and measurement technique of quasi-longitudinal waves, analyzes the bias error due to the effect of bending waves. In a two-dimensional quasi-longitudinal wave field, the intensity vector is the sum of the effective intensity vector and the intensity variation vector. Its axial component is proportional to two imaginary parts of cross spectral densities and in the measurement, it is measured by a pair of two-transducer arrays. In a onedimensional quasi-longitudinal wave field, the intensity variation is zero, the intensity is proportional to only one imaginary part of a cross spectral density and it can be measured using a two-transducer array. If bending and quasi-longitudinal waves coexist and the contribution from bending waves cannot be eliminated or reduced to a certain extent, the measured quasi-longitudinal wave intensity will contain a large error. The results measured on the three-beam structure show that quasi-longitudinal wave intensity can be accurately measured using the intensity technique when bending waves are negligible in comparison with quasi-longitudinal waves.

  9. Evaluating Longitudinal Mathematics Achievement Growth: Modeling and Measurement Considerations for Assessing Academic Progress

    ERIC Educational Resources Information Center

    Shanley, Lina

    2016-01-01

    Accurately measuring and modeling academic achievement growth is critical to support educational policy and practice. Using a nationally representative longitudinal data set, this study compared various models of mathematics achievement growth on the basis of both practical utility and optimal statistical fit and explored relationships within and…

  10. 29. HAWSER DEVICE, DEVELOPED AT WES FOR MEASURING LONGITUDINAL AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    29. HAWSER DEVICE, DEVELOPED AT WES FOR MEASURING LONGITUDINAL AND TRANSVERSE STRESS OF BARGES IN CANAL LOCKS. - Waterways Experiment Station, Hydraulics Laboratory, Halls Ferry Road, 2 miles south of I-20, Vicksburg, Warren County, MS

  11. Evaluation of a Longitudinal Advanced Pharmacy Practice Experience.

    PubMed

    Frasiolas, Jorie A; Wright, Kelly; Dzierba, Amy L

    2017-04-01

    Objective. To describe satisfaction and career path of students who participated in the longitudinal advanced pharmacy practice experience (APPE). Methods. A 3-part survey was administered to students enrolled between January 1, 2010, and December 31, 2013. The sections of the survey evaluated respondents' baseline characteristics, satisfaction, and career path. Results. Majority of the respondents had a GPA above 3.0 (91%), pharmacy school honors (84%), work experience in retail (16%) or multiple pharmacy sites (38%), and were members of at least one professional organization (76%). Sixty-nine percent reported that the program exceeded their expectations. Strengths included practice site consistency, rotation diversity, preceptors, presentations, and collaboration with health care professionals. Students gained approximately 76 hours of additional clinical experience, compared to if they completed rotations at individual sites. After graduation, more than half of the respondents accepted a pharmacy practice residency (67%). Conclusion. The results of this study support the need for APPE programs that prepare students to deliver advanced patient care, while providing them with professional development.

  12. Exploring Intensive Longitudinal Measures of Student Engagement in Blended Learning

    ERIC Educational Resources Information Center

    Henrie, Curtis R.; Bodily, Robert; Manwaring, Kristine C.; Graham, Charles R.

    2015-01-01

    In this exploratory study we used an intensive longitudinal approach to measure student engagement in a blended educational technology course, collecting both self-report and observational data. The self-report measure included a simple survey of Likert-scale and open-ended questions given repeatedly during the semester. Observational data were…

  13. Longitudinal associations between family characteristics and measures of childhood obesity.

    PubMed

    Lehto, Reetta; Ray, Carola; Roos, Eva

    2012-06-01

    The objective of this study was to investigate cross-sectional and longitudinal associations between different family characteristics and body mass index (BMI) and waist-to-height ratio (WHtR) in children. This was a prospective follow-up study conducted in Helsinki region with data collected in 2006 and 2008. The sample consisted of 550 children aged 9-11 at baseline. Children were measured and weighed by research staff, and they completed a questionnaire about their family characteristics. More meals together with the family, more parenting practices at meals, less time home without adult company after school, and child's perception of receiving care from mother in 2006 predicted a lower BMI in 2008 and partly a smaller increase in BMI from 2006 to 2008. Fewer associations were found to WHtR. Physical activity with either parent was not associated with BMI or WHtR. Several family characteristics predicted child BMI and WHtR 2 years later. These results contribute new knowledge about parental influence on child weight and weight gain and should be taken into account when planning interventions on the matter.

  14. Procedure of measuring the longitudinal emittance of electron beam

    NASA Astrophysics Data System (ADS)

    Vladimirov, I. Yu

    2016-09-01

    The procedure of measuring the longitudinal emittance of electron beam generated by RF gun and reconstruction of its longitudinal phase portrait is proposed. Measuring system consists of vertical deflecting RF cavity, horizontal bending dipole and screen. The beam spot on the screen is used to reconstruct the longitudinal phase portrait. In the proposed procedure an electromagnetic field of the vertical deflecting RF cavity can be approximated by the TM110 mode of pillbox cavity. This approximation allows analytically solve the motion equations of the electron motion in the vertical deflecting RF cavity. The report contains description of the vertical deflecting RF cavity and the dipole, the formulae underlying the procedure and the results of numerical simulation.

  15. Measurement of longitudinal electron diffusion in liquid argon

    DOE PAGES

    Li, Yichen; Tsang, Thomas; Thorn, Craig; ...

    2016-02-07

    In this paper, we report the measurement of longitudinal electron diffusion coefficients in liquid argon for electric fields between 100 and 2000 V/cm with a gold photocathode as a bright electron source. The measurement principle, apparatus, and data analysis are described. In the region between 100 and 350 V/cm, our results show a discrepancy with the previous measurement. In the region between 350 and 2000 V/cm, our results represent the world's best measurement. Over the entire measured electric field range, our results are systematically higher than the calculation of Atrazhev-Timoshkin. The quantum efficiency of the gold photocathode, the drift velocitymore » and longitudinal diffusion coefficients in gas argon are also presented.« less

  16. Measurement of longitudinal electron diffusion in liquid argon

    SciTech Connect

    Li, Yichen; Tsang, Thomas; Thorn, Craig; Qian, Xin; Diwan, Milind; Joshi, Jyoti; Kettell, Steve; Morse, William; Rao, Triveni; Stewart, James; Tang, Wei; Viren, Brett

    2016-02-07

    In this paper, we report the measurement of longitudinal electron diffusion coefficients in liquid argon for electric fields between 100 and 2000 V/cm with a gold photocathode as a bright electron source. The measurement principle, apparatus, and data analysis are described. In the region between 100 and 350 V/cm, our results show a discrepancy with the previous measurement. In the region between 350 and 2000 V/cm, our results represent the world's best measurement. Over the entire measured electric field range, our results are systematically higher than the calculation of Atrazhev-Timoshkin. The quantum efficiency of the gold photocathode, the drift velocity and longitudinal diffusion coefficients in gas argon are also presented.

  17. [The problem of repeated measurements. Longitudinal analysis in epidemiology].

    PubMed

    Sáez, M

    2001-01-01

    In longitudinal analyses subjects are repeatedly measured along time. They are mixed designs, characterised for their simultaneous consideration of two or more dimensions of analysis, in which time is one of the dimensions.Longitudinal analyses have important advantages with respect other designs. The most important is that they are more efficient, since they allow to distinguish between-individual and within-individual variation.Longitudinal analyses can be approached marginal and conditionally. Whereas the former allows to draw poblational, or average, inferences, the latter permits to draw individual inferences.The statistical models to use depend on the type of response variable. If the dependent variable is normally distributed one will use linear mixed models. When the response is a count one will use mixed Poisson regressions. Mixed binomial or multinomial logistic regressions should be used when the response would be categorical.

  18. Measurement and simulation of the RHIC abort kicker longitudinal impedence

    SciTech Connect

    Abreu,N.P.; Hahn,H.; Choi, E.

    2009-09-01

    In face of the new upgrades for RHIC the longitudinal impedance of the machine plays an important role in setting the threshold for instabilities and the efficacy of some systems. In this paper we describe the measurement of the longitudinal impedance of the abort kicker for RHIC as well as computer simulations of the structure. The impedance measurement was done by the S{sub 21} wire method covering the frequency range from 9 kHz to 2.5 GHz. We observed a sharp resonance peak around 10 MHz and a broader peak around 20 MHz in both, the real and imaginary part, of the Z/n. These two peaks account for a maximum imaginary longitudinal impedance of j15 {Omega}, a value an order of magnitude larger than the estimated value of j0.2 {Omega}, which indicates that the kicker is one of the main sources of longitudinal impedance in the machine. A computer model was constructed for simulations in the CST MWS program. Results for the magnet input and the also the beam impedance are compared to the measurements. A more detail study of the system properties and possible changes to reduce the coupling impedance are presented.

  19. The Feeding Practices and Structure Questionnaire (FPSQ-28): A parsimonious version validated for longitudinal use from 2 to 5 years.

    PubMed

    Jansen, Elena; Williams, Kate E; Mallan, Kimberley M; Nicholson, Jan M; Daniels, Lynne A

    2016-05-01

    Prospective studies and intervention evaluations that examine change over time assume that measurement tools measure the same construct at each occasion. In the area of parent-child feeding practices, longitudinal measurement properties of the questionnaires used are rarely verified. To ascertain that measured change in feeding practices reflects true change rather than change in the assessment, structure, or conceptualisation of the constructs over time, this study examined longitudinal measurement invariance of the Feeding Practices and Structure Questionnaire (FPSQ) subscales (9 constructs; 40 items) across 3 time points. Mothers participating in the NOURISH trial reported their feeding practices when children were aged 2, 3.7, and 5 years (N = 404). Confirmatory Factor Analysis (CFA) within a structural equation modelling framework was used. Comparisons of initial cross-sectional models followed by longitudinal modelling of subscales, resulted in the removal of 12 items, including two redundant or poorly performing subscales. The resulting 28-item FPSQ-28 comprised 7 multi-item subscales: Reward for Behaviour, Reward for Eating, Persuasive Feeding, Overt Restriction, Covert Restriction, Structured Meal Setting and Structured Meal Timing. All subscales showed good fit over 3 time points and each displayed at least partial scalar (thresholds equal) longitudinal measurement invariance. We recommend the use of a separate single item indicator to assess the family meal setting. This is the first study to examine longitudinal measurement invariance in a feeding practices questionnaire. Invariance was established, indicating that the subscales of the shortened FPSQ-28 can be used with mothers to validly assess change in 7 feeding constructs in samples of children aged 2-5 years of age.

  20. Does a quality management system improve quality in primary care practices in Switzerland? A longitudinal study

    PubMed Central

    Goetz, Katja; Hess, Sigrid; Jossen, Marianne; Huber, Felix; Rosemann, Thomas; Brodowski, Marc; Künzi, Beat; Szecsenyi, Joachim

    2015-01-01

    Objectives To examine the effectiveness of the quality management programme—European Practice Assessment—in primary care in Switzerland. Design Longitudinal study with three points of measurement. Setting Primary care practices in Switzerland. Participants In total, 45 of 91 primary care practices completed European Practice Assessment three times. Outcomes The interval between each assessment was around 36 months. A variance analyses for repeated measurements were performed for all 129 quality indicators from the domains: ‘infrastructure’, ‘information’, ‘finance’, and ‘quality and safety’ to examine changes over time. Results Significant improvements were found in three of four domains: ‘quality and safety’ (F=22.81, p<0.01), ‘information’ (F=27.901, p<0.01) and ‘finance’ (F=4.073, p<0.02). The 129 quality indicators showed a significant improvement within the three points of measurement (F=33.864, p<0.01). Conclusions The European Practice Assessment for primary care practices thus provides a functioning quality management programme, focusing on the sustainable improvement of structural and organisational aspects to promote high quality of primary care. The implementation of a quality management system which also includes a continuous improvement process would give added value to provide good care. PMID:25900466

  1. Recommended Practices in Thrust Measurements

    NASA Technical Reports Server (NTRS)

    Polk, James E.; Pancotti, Anthony; Haag, Thomas; King, Scott; Walker, Mitchell; Blakely, Joseph; Ziemer, John

    2013-01-01

    Accurate, direct measurement of thrust or impulse is one of the most critical elements of electric thruster characterization, and one of the most difficult measurements to make. The American Institute of Aeronautics and Astronautics has started an initiative to develop standards for many important measurement processes in electric propulsion, including thrust measurements. This paper summarizes recommended practices for the design, calibration, and operation of pendulum thrust stands, which are widely recognized as the best approach for measuring micro N- to mN-level thrust and micro Ns-level impulse bits. The fundamentals of pendulum thrust stand operation are reviewed, along with its implementation in hanging pendulum, inverted pendulum, and torsional balance configurations. Methods of calibration and recommendations for calibration processes are presented. Sources of error are identified and methods for data processing and uncertainty analysis are discussed. This review is intended to be the first step toward a recommended practices document to help the community produce high quality thrust measurements.

  2. Recommended Practices in Thrust Measurements

    NASA Technical Reports Server (NTRS)

    Polk, James E.; Pancotti, Anthony; Haag, Thomas; King, Scott; Walker, Mitchell; Blakely, Joseph; Ziemer, John

    2013-01-01

    Accurate, direct measurement of thrust or impulse is one of the most critical elements of electric thruster characterization, and one of the most difficult measurements to make. The American Institute of Aeronautics and Astronautics has started an initiative to develop standards for many important measurement processes in electric propulsion, including thrust measurements. This paper summarizes recommended practices for the design, calibration, and operation of pendulum thrust stands, which are widely recognized as the best approach for measuring micro N- to mN-level thrust and micro Ns-level impulse bits. The fundamentals of pendulum thrust stand operation are reviewed, along with its implementation in hanging pendulum, inverted pendulum, and torsional balance configurations. Methods of calibration and recommendations for calibration processes are presented. Sources of error are identified and methods for data processing and uncertainty analysis are discussed. This review is intended to be the first step toward a recommended practices document to help the community produce high quality thrust measurements.

  3. A practical longitudinal model for evaluating growth in Gelbvieh cattle.

    PubMed

    Robbins, K R; Misztal, I; Bertrand, J K

    2005-01-01

    Genetic evaluation of growth in Gelbvieh beef cattle was examined by multiple-trait (MTM) and random regression (RRM) analysis. The data set comprised 541,108 animals with 1,120,086 records. Approximately 15% of the animals in the data set had at least one record measured outside of the accepted MTM age ranges for weaning weight (Wwt) and yearling weight (Ywt). Fourteen percent of Wwt records and 19% of Ywt records were measured outside the accepted ranges for MTM analysis, and thus were excluded from MTM evaluations. Two RRM evaluations were performed using cubic Legendre polynomials (RRML) and linear splines (RRMS) with three knots at 1, 205, and 365 d of age. Data Set 1 (d1) utilized all available records, whereas Data Set 2 (d2) included only records measured within MTM ranges (1 d, 160 to 250 d, and 320 to 410 d). The RRML models did not reach convergence until diagonalization was imposed. After diagonalization, it was found that all longitudinal models required fewer iterations to converge than the MTM. Correlations between the MTM, RRML-d2, and RRMS-d2 evaluations were >or=0.99 for all three traits, indicating that these models were equivalent when predicting breeding values from data within the MTM age ranges. Correlations between MTM, RRML-d1, and RRMS-d1 were >0.99 for Bwt and >0.95 for Wwt and Ywt. The lower correlations for Wwt and Ywt indicate that the added information does affect breeding value prediction. The RRM has the capability to incorporate records measured at all ages into genetic evaluations at a computing cost similar to the MTM.

  4. Temporal Stability of Implicit and Explicit Measures: A Longitudinal Analysis.

    PubMed

    Gawronski, Bertram; Morrison, Mike; Phills, Curtis E; Galdi, Silvia

    2017-03-01

    A common assumption about implicit measures is that they reflect early experiences, whereas explicit measures are assumed to reflect recent experiences. This assumption subsumes two distinct hypotheses: (a) Implicit measures are more resistant to situationally induced changes than explicit measures; (b) individual differences on implicit measures are more stable over time than individual differences on explicit measures. Although the first hypothesis has been the subject of numerous studies, the second hypothesis has received relatively little attention. The current research addressed the second hypothesis in two longitudinal studies that compared the temporal stability of individual differences on implicit and explicit measures in three content domains (self-concept, racial attitudes, political attitudes). In both studies, implicit measures showed significantly lower stability over time (weighted average r = .54) than conceptually corresponding explicit measures (weighted average r = .75), despite comparable estimates of internal consistency. Implications for theories of implicit social cognition and interpretations of implicit and explicit measures are discussed.

  5. Objective Measures for Longitudinal Assessment of Robotic Surgery Training

    PubMed Central

    Kumar, Rajesh; Jog, Amod; Vagvolgyi, Balazs; Nguyen, Hiep; Hager, Gregory; Chen, Chi Chiung Grace; Yuh, David

    2011-01-01

    Objectives Current robotic training approaches lack criteria for automatically assessing and tracking (over time) technical skills separately from clinical proficiency. We describe the development and validation of a novel automated and objective framework for assessment of training. Methods We are able to record all system variables (stereo instrument video, hand and instrument motion, buttons and pedal events) from the da Vinci surgical systems using a portable archival system integrated with the robotic surgical system. Data can be collected unsupervised, and the archival system does not change system operation in any way. Our open-ended multi-center protocol is collecting surgical skill benchmarking data from 24 trainees to surgical proficiency, subject only to their continued availability. Two independent experts performed structured (OSATS) assessments on longitudinal data from 8 novice and 4 expert surgeons to generate ground truth for training and to validate our computerized statistical analysis methods in identifying ranges of operational and clinical skill measures. Results Objective differences in operational and technical skill between known experts and other subjects were quantified. Longitudinal learning curves and statistical analysis for trainee performance measures are reported. Graphical representations of skills developed for feedback to the trainees are also included. Conclusions We describe an open-ended longitudinal study and automated motion recognition system capable of objectively differentiating between clinical and technical operational skills in robotic surgery. Our results demonstrate a convergence of trainee skill parameters towards those derived from expert robotic surgeons over the course of our training protocol. PMID:22172215

  6. Correlating Function and Imaging Measures of the Medial Longitudinal Fasciculus

    PubMed Central

    Sakaie, Ken; Takahashi, Masaya; Remington, Gina; Wang, Xiaofeng; Conger, Amy; Conger, Darrel; Dimitrov, Ivan; Jones, Stephen; Frohman, Ashley; Frohman, Teresa; Sagiyama, Koji; Togao, Osamu

    2016-01-01

    Objective To test the validity of diffusion tensor imaging (DTI) measures of tissue injury by examining such measures in a white matter structure with well-defined function, the medial longitudinal fasciculus (MLF). Injury to the MLF underlies internuclear ophthalmoparesis (INO). Methods 40 MS patients with chronic INO and 15 healthy controls were examined under an IRB-approved protocol. Tissue integrity of the MLF was characterized by DTI parameters: longitudinal diffusivity (LD), transverse diffusivity (TD), mean diffusivity (MD) and fractional anisotropy (FA). Severity of INO was quantified by infrared oculography to measure versional disconjugacy index (VDI). Results LD was significantly lower in patients than in controls in the medulla-pons region of the MLF (p < 0.03). FA was also lower in patients in the same region (p < 0.0004). LD of the medulla-pons region correlated with VDI (R = -0.28, p < 0.05) as did FA in the midbrain section (R = 0.31, p < 0.02). Conclusions This study demonstrates that DTI measures of brain tissue injury can detect injury to a functionally relevant white matter pathway, and that such measures correlate with clinically accepted evaluation indices for INO. The results validate DTI as a useful imaging measure of tissue integrity. PMID:26800522

  7. Longitudinal measurement invariance, stability and change of anger and cynicism.

    PubMed

    Hakulinen, Christian; Jokela, Markus; Keltikangas-Järvinen, Liisa; Merjonen, Päivi; Raitakari, Olli T; Hintsanen, Mirka

    2014-06-01

    Anger and hostility are key concepts in behavioral medicine, but little is known about their stability over life course. A sample of 3,074 individuals from six age groups (aged 15-30 at the baseline) were selected from a population-based study to examine longitudinal measurement invariance, stability and change in anger and cynicism from early to middle adulthood over 15 years. Cynicism, a facet of hostility, and anger were measured 4 times in 1992, 1997, 2001 and 2007. Final longitudinal measurement invariance models achieved partial strict measurement invariance, indicating good measurement consistency over time. Rank-order stability of anger and cynicism was found to be moderate. Mean levels of anger and cynicism decreased over time, but in anger the decline was faster among women. The variance of anger and cynicism also increased over time, but in cynicism the rate of change was higher among men. Altogether, anger and cynicism show measurement invariance and moderate stability from early adulthood to middle adulthood.

  8. Simultaneous inference and bias analysis for longitudinal data with covariate measurement error and missing responses.

    PubMed

    Yi, G Y; Liu, W; Wu, Lang

    2011-03-01

    Longitudinal data arise frequently in medical studies and it is common practice to analyze such data with generalized linear mixed models. Such models enable us to account for various types of heterogeneity, including between- and within-subjects ones. Inferential procedures complicate dramatically when missing observations or measurement error arise. In the literature, there has been considerable interest in accommodating either incompleteness or covariate measurement error under random effects models. However, there is relatively little work concerning both features simultaneously. There is a need to fill up this gap as longitudinal data do often have both characteristics. In this article, our objectives are to study simultaneous impact of missingness and covariate measurement error on inferential procedures and to develop a valid method that is both computationally feasible and theoretically valid. Simulation studies are conducted to assess the performance of the proposed method, and a real example is analyzed with the proposed method.

  9. Brain atrophy associated with baseline and longitudinal measures of cognition

    PubMed Central

    Cardenas, V.A.; Chao, L.L.; Studholme, C.; Yaffe, K.; Miller, B.L.; Madison, C.; Buckley, S.T.; Mungas, D.; Schuff, N.; Weiner, M.W.

    2009-01-01

    The overall goal was to identify patterns of brain atrophy associated with cognitive impairment and future cognitive decline in non-demented elders. Seventy-one participants were studied with structural MRI and neuropsychological testing at baseline and 1 year follow-up. Deformation-based morphometry was used to examine the relationship between regional baseline brain tissue volume with baseline and longitudinal measures of delayed verbal memory, semantic memory, and executive function. Smaller right hippocampal and entorhinal cortex (ERC) volumes at baseline were associated with worse delayed verbal memory performance at baseline while smaller left ERC volume was associated with greater longitudinal decline. Smaller left superior temporal cortex at baseline was associated with worse semantic memory at baseline, while smaller left temporal white and gray matter volumes were associated with greater semantic memory decline. Increased CSF and smaller frontal lobe volumes were associated with impaired executive function at baseline and greater longitudinal executive decline. These findings suggest that baseline volumes of prefrontal and temporal regions may underlie continuing cognitive decline due to aging, pathology, or both in non-demented elderly individuals. PMID:19446370

  10. New measurements of longitudinal spin asymmetries in pion electroproduction

    NASA Astrophysics Data System (ADS)

    Bosted, Peter; CLAS Collaboration

    2014-09-01

    We present new preliminary results for the longitudinal beam, target, and beam-target spin asymmetries in exclusive electro-production of charged and neutral pions. The measurements cover a wide range of four-momentum transfer squared (up to 4 GeV2), and invariant final mass W (up to 2.4 GeV). The results come from two experiments using the CLAS instrument in Hall B at Jefferson Lab. The first experiment used 1.6, 2.4, 4.2, and 5.7 GeV longitudinally polarized electrons with scattering angles ranging from 10 to 45 degrees. The second experiment used 6 GeV electrons scattering at angles form 16 to 45 degrees. Both experiments used a longitudinally polarized NH3 target for π+ and π0 production from polarized protons, and an ND3 target for π- production from polarized neutrons. The preliminary results indicate the possible presence of baryon resonance excitations at relatively high masses (W > 1 . 6 GeV). The status of a simple empirical fit to the results will be presented. It is hoped that the new results will be used in global unitary isobar fits in order to improve the knowledge of baryon resonance structure.

  11. Evaluation of thermal gradients in longitudinal spin Seebeck effect measurements

    NASA Astrophysics Data System (ADS)

    Sola, A.; Kuepferling, M.; Basso, V.; Pasquale, M.; Kikkawa, T.; Uchida, K.; Saitoh, E.

    2015-05-01

    In the framework of the longitudinal spin Seebeck effect (LSSE), we developed an experimental setup for the characterization of LSSE devices. This class of device consists in a layered structure formed by a substrate, a ferrimagnetic insulator (YIG) where the spin current is thermally generated, and a paramagnetic metal (Pt) for the detection of the spin current via the inverse spin-Hall effect. In this kind of experiments, the evaluation of a thermal gradient through the thin YIG layer is a crucial point. In this work, we perform an indirect determination of the thermal gradient through the measurement of the heat flux. We developed an experimental setup using Peltier cells that allow us to measure the heat flux through a given sample. In order to test the technique, a standard LSSE device produced at Tohoku University was measured. We find a spin Seebeck SSSE coefficient of 2.8 × 10 - 7 V K-1.

  12. Impact of Curriculum on Understanding of Professional Practice: A Longitudinal Study of Students Commencing Dental Education

    ERIC Educational Resources Information Center

    Kieser, Jules A.; Dall'Alba, Gloria; Livingstone, Vicki

    2009-01-01

    This longitudinal study examines changes in understanding of dental practice among a cohort of students in the early years of a dentistry programme. In their first two professional years, we identified five distinct understandings of dental practice that we have ordered from least to most comprehensive: "relieving pain or generally caring for…

  13. Impact of Curriculum on Understanding of Professional Practice: A Longitudinal Study of Students Commencing Dental Education

    ERIC Educational Resources Information Center

    Kieser, Jules A.; Dall'Alba, Gloria; Livingstone, Vicki

    2009-01-01

    This longitudinal study examines changes in understanding of dental practice among a cohort of students in the early years of a dentistry programme. In their first two professional years, we identified five distinct understandings of dental practice that we have ordered from least to most comprehensive: "relieving pain or generally caring for…

  14. The Role of Practice in Chess: A Longitudinal Study

    ERIC Educational Resources Information Center

    Campitelli, Guillermo; Gobet, Fernand

    2008-01-01

    We investigated the role of practice in the acquisition of chess expertise by submitting a questionnaire to 104 players of different skill levels. Players had to report their chess rating, the number of hours of individual and group practice, their use of different learning resources and activities, and whether they had been trained by a coach.…

  15. The Role of Practice in Chess: A Longitudinal Study

    ERIC Educational Resources Information Center

    Campitelli, Guillermo; Gobet, Fernand

    2008-01-01

    We investigated the role of practice in the acquisition of chess expertise by submitting a questionnaire to 104 players of different skill levels. Players had to report their chess rating, the number of hours of individual and group practice, their use of different learning resources and activities, and whether they had been trained by a coach.…

  16. Parenting Practices and Adolescent Sexual Behavior: A Longitudinal Study

    ERIC Educational Resources Information Center

    Bersamin, Melina; Todd, Michael; Fisher, Deborah A.; Hill, Douglas L.; Grube, Joel W.; Walker, Samantha

    2008-01-01

    The effects of parental attitudes, practices, and television mediation on adolescent sexual behaviors were investigated in a study of adolescent sexuality and media (N = 887). Confirmatory factor analyses supported an eight-factor parenting model with television mediation factors as constructs distinct from general parenting practices. Logistic…

  17. Parenting Practices and Adolescent Sexual Behavior: A Longitudinal Study

    ERIC Educational Resources Information Center

    Bersamin, Melina; Todd, Michael; Fisher, Deborah A.; Hill, Douglas L.; Grube, Joel W.; Walker, Samantha

    2008-01-01

    The effects of parental attitudes, practices, and television mediation on adolescent sexual behaviors were investigated in a study of adolescent sexuality and media (N = 887). Confirmatory factor analyses supported an eight-factor parenting model with television mediation factors as constructs distinct from general parenting practices. Logistic…

  18. Parenting practices and school dropout: a longitudinal study.

    PubMed

    Blondal, Kristjana S; Adalbjarnardottir, Sigrun

    2009-01-01

    Adolescents' perceptions of parenting style and parental involvement in their education were examined longitudinally and related to school dropout among Icelandic youth (N = 427). Results indicated that adolescents who, at age 14, characterized their parents as authoritative (showing acceptance and supervision) were more likely to have completed upper secondary school by age 22 than adolescents from non-authoritative families, controlling for adolescents' gender, socioeconomic status (SES), temperament, and parental involvement. Parenting style seems to more strongly predict school dropout than parental involvement. Further, parenting style may moderate the relationship between parental involvement and dropout, but not in all groups; only in authoritative families does parental involvement decrease the likelihood of school dropout. Furthermore, even after controlling for previous academic achievement, adolescents from authoritative families were less likely to drop out than adolescents from authoritarian and neglectful families. These findings emphasize the importance of encouraging quality parent-child relationships in order to reduce the likelihood of school dropout.

  19. Teachers developing exemplary inquiry practices: Three longitudinal case studies

    NASA Astrophysics Data System (ADS)

    Sweetman, Sara Berry

    If students are to be successful in the ever-changing scientific world they need to be taught how to think critically, to manipulate materials, and to gather evidence to build knowledge. Most teachers fall short in providing students the inquiry instruction described in the Next Generation Science Frameworks (National Research Council, 2011). This study examined three elementary science teachers' processes as they developed inquiry practices over time. The Electronic Quality of Inquiry Protocol (EQUIP) was used to gather quantitative and qualitative evidence of the teachers' inquiry practices in terms of four factors, Curriculum, Instruction, Discourse, and Assessment. A chronological analysis was used to examine the teachers' professional development and curriculum experiences in relation to their teaching practices. The results showed that all three teachers did change their practice, although the changes varied among cases. For each case, multiple factors influenced the teacher's development. There was a strong positive correlation between the quality of the teachers' inquiry practices and the time spent in curriculum-contextualized professional development. This research indicates that when teachers are supported with curriculum and professional development over extended periods, they develop exemplary inquiry practices. Three recommendations are provided for those interested in implementing science education reform.

  20. Reconstruction of sub-femtosecond longitudinal bunch profile measurement data

    NASA Astrophysics Data System (ADS)

    Weikum, M. K.; Andonian, G.; Assmann, R. W.; Dorda, U.; Sheng, Z. M.

    2017-07-01

    With a current trend towards shorter electron beams with lengths on the order of few femtoseconds (fs) to sub-femtoseconds both in conventional and novel accelerator communities, the need for diagnostics with equivalent attosecond resolution is increasing. The proposed design for a sub-femtosecond diagnostic by Andonian et al. (2011, Phys. Rev. ST Accel. Beams 14 072802) is one such example that combines a laser deflector with an RF deflecting cavity to streak the electron beam in the horizontal and vertical direction. In this paper, we present a tool for the reconstruction of the longitudinal beam profile from this diagnostic data, which can be used both for the analysis of planned experiments and testing of different beam scenarios with respect to their specific setup requirements. Applying this method, the usefulness of the device for measurements in a number of example scenarios, including plasma-accelerated and ultrashort RF-accelerated electron beams, is discussed.

  1. Longitudinal Study of a Novel, Performance-based Measure of Daily Function

    DTIC Science & Technology

    2016-06-01

    was not longitudinal. Therefore, it is important that we obtain data on the longitudinal characteristics of the UPSA in these populations , including...obtain data on the longitudinal characteristics of the UPSA in these populations , including the severity of decline in this measure over time, the...Therefore, it is important that we obtain data on the longitudinal characteristics of the UPSA in these populations , including the severity of decline in

  2. The Case for Measuring Adults' Numeracy Practices

    ERIC Educational Resources Information Center

    Coben, Diana; Alkema, Anne

    2017-01-01

    In this article, we make the case for the development of a numeracy practices measure in the light of a review of relevant research and extant measures. We argue that a numeracy practices measure would acknowledge and validate adult learners' practice gains and inform teaching geared to their circumstances, needs and interests.

  3. Measuring Mathematical Knowledge for Teaching: A Longitudinal Study Using Two Measures

    ERIC Educational Resources Information Center

    Copur-Gencturk, Yasemin; Lubienski, Sarah T.

    2013-01-01

    This longitudinal study examines growth in teacher knowledge as measured by two popular assessments--Learning Mathematics for Teaching (LMT) and Diagnostic Teacher Assessments in Mathematics and Science (DTAMS). Using data collected from 24 teachers, we compare the extent to which each assessment captured teacher learning during a K-8 mathematics…

  4. Evaluation of thermal gradients in longitudinal spin Seebeck effect measurements

    SciTech Connect

    Sola, A. Kuepferling, M.; Basso, V.; Pasquale, M.; Kikkawa, T.; Uchida, K.; Saitoh, E.

    2015-05-07

    In the framework of the longitudinal spin Seebeck effect (LSSE), we developed an experimental setup for the characterization of LSSE devices. This class of device consists in a layered structure formed by a substrate, a ferrimagnetic insulator (YIG) where the spin current is thermally generated, and a paramagnetic metal (Pt) for the detection of the spin current via the inverse spin-Hall effect. In this kind of experiments, the evaluation of a thermal gradient through the thin YIG layer is a crucial point. In this work, we perform an indirect determination of the thermal gradient through the measurement of the heat flux. We developed an experimental setup using Peltier cells that allow us to measure the heat flux through a given sample. In order to test the technique, a standard LSSE device produced at Tohoku University was measured. We find a spin Seebeck S{sub SSE} coefficient of 2.8×10{sup −7} V K{sup −1}.

  5. Parenting practices and adolescent sexual behavior: A longitudinal study

    PubMed Central

    Bersamin, Melina; Todd, Michael; Fisher, Deborah A.; Hill, Douglas L.; Grube, Joel W.; Walker, Samantha

    2009-01-01

    The effects of parental attitudes, practices, and television mediation on adolescent sexual behaviors were investigated in a study of adolescent sexuality and media (N=887). Confirmatory factor analyses supported an eight-factor parenting model with television mediation factors as constructs distinct from general parenting practices. Logistic regressions indicated that adolescents reporting greater parental disapproval and limits on viewing at Wave 1 were less likely to initiate oral sex between Waves 1 and 2. Adolescents who reported more sexual communication with parents were more likely to initiate oral sex. Results for vaginal intercourse were similar to those for oral sex. Co-viewing was a significant negative predictor of initiation of sexual behavior. Parental attitudes and television mediation can delay potentially risky adolescent sexual behaviors. PMID:19750131

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

    ERIC Educational Resources Information Center

    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…

  7. Preschool Home Literacy Practices and Children's Literacy Development: A Longitudinal Analysis

    ERIC Educational Resources Information Center

    Hood, Michelle; Conlon, Elizabeth; Andrews, Glenda

    2008-01-01

    In this 3-year longitudinal study, the authors tested and extended M. Senechal and J. Le Fevre's (2002) model of the relationships between preschool home literacy practices and children's literacy and language development. Parent-child reading (Home Literacy Environment Questionnaire plus a children's Title Recognition Test) and parental teaching…

  8. Building a Constructivist Practice: A Longitudinal Study of Beginning History Teachers

    ERIC Educational Resources Information Center

    Martell, Christopher C.

    2014-01-01

    This longitudinal interpretative case study examined the constructivist beliefs and related practices of four secondary history teachers from their teacher preparation through their first year in the classroom. The results of this study showed that issues of classroom control were major barriers for the implementation of constructivist-oriented…

  9. The Link between High-Impact Practices and Student Learning: Some Longitudinal Evidence

    ERIC Educational Resources Information Center

    Kilgo, Cindy A.; Ezell Sheets, Jessica K.; Pascarella, Ernest T.

    2015-01-01

    The current paper used data from the Wabash National Study of Liberal Arts Education--a longitudinal, pretest/posttest design--to estimate the effects of participation in the ten "high-impact" educational practices put forth and endorsed by the Association of American Colleges and Universities (AAC&U) on a variety of liberal arts…

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

    ERIC Educational Resources Information Center

    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…

  11. "Flat" versus "Weighted" Reimbursement Formulas: A Longitudinal Analysis of State-Wide Special Education Funding Practices.

    ERIC Educational Resources Information Center

    Dempsey, Samuel; Fuchs, Douglas

    Tennessee data were analyzed longitudinally from 1979-80 to 1987-88 to compare statewide special education practice associated with two student-based formulas for funding disbursement: "flat" versus "weighted.""Flat" grants, used from 1979-80 to 1982-83, provided a fixed amount of funds per child, teacher, or…

  12. The Link between High-Impact Practices and Student Learning: Some Longitudinal Evidence

    ERIC Educational Resources Information Center

    Kilgo, Cindy A.; Ezell Sheets, Jessica K.; Pascarella, Ernest T.

    2015-01-01

    The current paper used data from the Wabash National Study of Liberal Arts Education--a longitudinal, pretest/posttest design--to estimate the effects of participation in the ten "high-impact" educational practices put forth and endorsed by the Association of American Colleges and Universities (AAC&U) on a variety of liberal arts…

  13. Maternal Cultural Values and Parenting Practices: Longitudinal Associations with Chinese Adolescents' Aggression

    ERIC Educational Resources Information Center

    Shuster, Michael M.; Li, Yan; Shi, Junqi

    2012-01-01

    Interrelations among cultural values, parenting practices, and adolescent aggression were examined using longitudinal data collected from Chinese adolescents and their mothers. Adolescents' overt and relational aggression were assessed using peer nominations at Time 1 (7th grade) and Time 2 (9th grade). Mothers reported endorsement of cultural…

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

    ERIC Educational Resources Information Center

    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…

  15. Maternal Cultural Values and Parenting Practices: Longitudinal Associations with Chinese Adolescents' Aggression

    ERIC Educational Resources Information Center

    Shuster, Michael M.; Li, Yan; Shi, Junqi

    2012-01-01

    Interrelations among cultural values, parenting practices, and adolescent aggression were examined using longitudinal data collected from Chinese adolescents and their mothers. Adolescents' overt and relational aggression were assessed using peer nominations at Time 1 (7th grade) and Time 2 (9th grade). Mothers reported endorsement of cultural…

  16. Measurement and calculation of PZT thin film longitudinal piezoelectric coefficients.

    SciTech Connect

    Christman, J. A.; Kim, S.-H.; Kingon, A. I.; Maiwa, H.; Maria, J.-P.; Streiffer, S. K.

    1999-04-26

    The ferroelectric and piezoelectric properties of 2000 {angstrom} thick chemical solution deposited Pb(Zr{sub x}Ti{sub 1{minus}x})O{sub 3} (PZT) thin films were investigated. Several Zr/Ti ratios were studied: 30/70, 50/50 and 65/35, which correspond to tetragonal, near-morphotropic, and rhombohedral symmetries. In all samples, a {l_brace}111{r_brace}-texture is predominant. Longitudinal piezoelectric coefficients and their dc field dependence were measured using the contact AFM method. The expected trend of a maximum piezoelectric coefficient at or near to the MPB was not observed. The composition dependence was small, with the maximum d{sub 33} occurring in the tetragonal material. To explain the results, crystallographic texture and film thickness effects are suggested. Using a modified phenomenological approach, derived electrostrictive coefficients, and experimental data, d{sub 33} values were calculated. Qualitative agreement was observed between the measured and calculated coefficients. Justifications of modifications to the calculations are discussed.

  17. Setting and Measuring the Longitudinal Optics in CEBAF Injector

    SciTech Connect

    R. Kazimi; C.K. Sinclair; G.A. Krafft

    2000-08-01

    The CEBAF injector is designed to produce three cw polarized beams to be simultaneously accelerated and delivered to three experimental halls. These beams have independent current controls that can be as low as few hundred pico-amperes or as high as 200 microamperes. The beams are created in a photocathode gun using 3 separate rf gain switched lasers each operating at 499 MHz which together make up 1497 MHz, the CEBAF fundamental frequency. At the gun, the beams have the same time structure as the lasers with about 55 pico-seconds bunch length at 499 MHz. Through the injector, this bunch length is then adiabatically reduced to about 2 pico-seconds. The main requirement is that the beams have short stable bunch lengths at the end of the injector. In this paper we discuss the longitudinal bunching process for the JLAB injector. We also describe how the bunch length is measured at various places along the injector and how the measurement results are used to set relative phases of the three lasers and the phases and amplitudes of various rf cavities with high precision.

  18. Measurement Invariance in Longitudinal Clinical Research Assuming Change from Development and Intervention.

    ERIC Educational Resources Information Center

    Pentz, Mary Ann; Chou, Chih-Ping

    1994-01-01

    Used empirical example of longitudinal experimental prevention study with two groups to illustrate use of structural equation modeling, first, to systematically test measurement invariance across groups at each wave of measurement, and second, after establishing measurement invariance, to test structural invariance longitudinally. (Author/NB)

  19. Recent Measurement of Debuncher Longitudinal Beam Size During Stacking

    SciTech Connect

    Halling, Mike

    1992-02-18

    During the recent co11ider studies period there were a few time periods when 120 GeV beam was delivered with a slow repetition rate. This gave us a rare chance to study the effectiveness of additional cooling in the antiproton source. The measurements shown below were taken on 1/15/92. Although we have several FFT analyzers connected to the debuncher schottkey monitor we cannot readout the measured spectrum except with a TV camera. The following measurements, therefore, were taken with a spectrum analyzer. It is necessary to use a resolution bandwidth of 100 HZ to see the effectiveness of the momentum cooling system, and therefore the sweep time was 3 seconds. It took about 1 hour to complete the series of measurements. The main ring performance was up to it's normal standards during this time period, but it's performance can vary greatly from on minute to the next. The debuncher longitudinal schottkey spectra are shown in Figures 1-5 with different trigger times for the spectrum analyzer. These are shown using a scale linear in power, which should also be linear in particle density. There are two effects of momentum cooling that are apparent. (1) The momentum distribution after bunch rotation has very long non-gaussian tails, momentum cooling rapidly pushes these tails into the central peak. (2) The width of the central peak is gradually reduced, as is shown in Table I. The FWHM shown in TABLE I is at h=127, and the 95% dp/p is the full width in percent dp/p that contains 95% of the beam.

  20. Maternal cultural values and parenting practices: longitudinal associations with Chinese adolescents' aggression.

    PubMed

    Shuster, Michael M; Li, Yan; Shi, Junqi

    2012-04-01

    Interrelations among cultural values, parenting practices, and adolescent aggression were examined using longitudinal data collected from Chinese adolescents and their mothers. Adolescents' overt and relational aggression were assessed using peer nominations at Time 1 (7th grade) and Time 2 (9th grade). Mothers reported endorsement of cultural values (collectivism and social harmony) and parenting practices (psychological control and inductive reasoning) at Time 1. While controlling for Time 1 adolescent aggression, maternal collectivism and social harmony indirectly and longitudinally linked to adolescent aggression through maternal parenting practices. Specifically, maternal collectivism was positively related to inductive reasoning, which, in turn, negatively related to adolescent overt aggression at Time 2. Similarly, maternal social harmony negatively related to psychological control that positively predicted later adolescent relational aggression. Results of the present study shed light on mechanisms through which culture may indirectly influence adolescent aggression.

  1. Online Assessment, Measurement and Evaluation: Emerging Practices

    ERIC Educational Resources Information Center

    Williams, David, Ed.; Hricko, Mary, Ed.; Howell, Scott, Ed.

    2006-01-01

    "Online Assessment, Measurement and Evaluation: Emerging Practices" provides a view of the possibilities and challenges facing online educators and evaluators in the 21st Century. As technology evolves and online measurement and assessment follow, "Online Assessment, Measurement and Evaluation: Emerging Practices" uses…

  2. Online Assessment, Measurement and Evaluation: Emerging Practices

    ERIC Educational Resources Information Center

    Williams, David, Ed.; Hricko, Mary, Ed.; Howell, Scott, Ed.

    2006-01-01

    "Online Assessment, Measurement and Evaluation: Emerging Practices" provides a view of the possibilities and challenges facing online educators and evaluators in the 21st Century. As technology evolves and online measurement and assessment follow, "Online Assessment, Measurement and Evaluation: Emerging Practices" uses…

  3. Infant feeding practices in a South African birth cohort-A longitudinal study.

    PubMed

    Budree, Shrish; Goddard, Elizabeth; Brittain, Kirsty; Cader, Shihaam; Myer, Landon; Zar, Heather J

    2016-10-02

    Childhood malnutrition is highly prevalent in low- and middle-income countries. The choices of complementary foods, which are important in infant nutrition, are poorly described in this setting. We investigated infant feeding practices in a South African birth cohort, the Drakenstein Child Health Study. Longitudinal feeding data were collected from March 2012 to March 2015. Feeding practices at birth, 6-10 and 14 weeks and 6, 9, and 12 months, were investigated using food frequency questionnaires. Anthropometry was measured at birth and 12 months. The quality of the diet was analyzed using the World Health Organization infant and young child feeding indicators. Regression models were used to explore associations between feeding and growth outcomes at 1 year. Exclusive breastfeeding for 6 months was low (13%), and 19% of infants were introduced to solid foods before 4 months. There was high daily consumption of processed meat (56%) and inappropriate foods such as fruit juice (82%), soft drinks (54%), and refined sugary foods (51%) at 1 year. Dietary diversity and consumption of iron rich foods were low at 6 months (5% and 3%, respectively) but higher by 12 months (75% and 78%). Longer duration of exclusive breastfeeding was associated with a lower height-for-age z-score at 1 year. Several dietary deficits and a rising trend in the consumption of inappropriate nutritionally poor foods were identified. These findings raise concern about poor dietary practices and the impact on child and long-term health.

  4. Current american practice in color measurement.

    PubMed

    Billmeyer, F W

    1969-04-01

    Current Aimerienn practice in color measurement is reviewed from the standpoint of instrumentation practice, measurement concepts, and computational methods. Instrumentation practice is described for spectrophotometers, abridged spectrophotometers, and tristimulus colorimeters. Measurement variables discussed include photometric and wavelength scales, standards and standardization, illuminating and viewing geometry, and instrument sources simulating standard illuminants. Computation-methods practiced for obtaining color coordinates and color differences are discussed. Topics indirectly related to the measurement step, such as the basis of colorimetry, color mixing laws, and computer color matching, are specifically excluded from this paper.

  5. Reactivity in Rapidly Collected Hygiene and Toilet Spot Check Measurements: A Cautionary Note for Longitudinal Studies

    PubMed Central

    Arnold, Benjamin F.; Khush, Ranjiv S.; Ramaswamy, Padmavathi; Rajkumar, Paramasivan; Durairaj, Natesan; Ramaprabha, Prabhakar; Balakrishnan, Kalpana; Colford Jr., John M.

    2015-01-01

    Discreet collection of spot check observations to measure household hygiene conditions is a common measurement technique in epidemiologic studies of hygiene in low-income countries. The objective of this study was to determine whether the collection of spot check observations in longitudinal studies could itself induce reactivity (i.e., change participant behavior). We analyzed data from a 12-month prospective cohort study in rural Tamil Nadu, India that was conducted in the absence of any hygiene or toilet promotion activities. Our data included hygiene and toilet spot checks from 10,427 household visits. We found substantial evidence of participant reactivity to spot check observations of hygiene practices that were easy to modify on short notice. For example, soap observed at the household's primary handwashing location increased from 49% at enrollment to 81% by the fourth visit and remained at or above 77% for the remainder of the study. PMID:25385856

  6. Reactivity in rapidly collected hygiene and toilet spot check measurements: a cautionary note for longitudinal studies.

    PubMed

    Arnold, Benjamin F; Khush, Ranjiv S; Ramaswamy, Padmavathi; Rajkumar, Paramasivan; Durairaj, Natesan; Ramaprabha, Prabhakar; Balakrishnan, Kalpana; Colford, John M

    2015-01-01

    Discreet collection of spot check observations to measure household hygiene conditions is a common measurement technique in epidemiologic studies of hygiene in low-income countries. The objective of this study was to determine whether the collection of spot check observations in longitudinal studies could itself induce reactivity (i.e., change participant behavior). We analyzed data from a 12-month prospective cohort study in rural Tamil Nadu, India that was conducted in the absence of any hygiene or toilet promotion activities. Our data included hygiene and toilet spot checks from 10,427 household visits. We found substantial evidence of participant reactivity to spot check observations of hygiene practices that were easy to modify on short notice. For example, soap observed at the household's primary handwashing location increased from 49% at enrollment to 81% by the fourth visit and remained at or above 77% for the remainder of the study. © The American Society of Tropical Medicine and Hygiene.

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

    PubMed Central

    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

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

    PubMed

    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 Y; Arseneault, Louise

    2015-11-01

    This paper presents multilevel 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 severity of 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 among children from low socioeconomic backgrounds. Exposure to multiple victimization types was common, as was revictimization; 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.

  9. Perturbation method for the measurement of longitudinal and transverse beam impedance

    SciTech Connect

    Barry, W.; Lambertson, G.R.

    1987-03-01

    A perturbation method utilizing metallic and dielectric spheres to measure longitudinal and transverse beam and pickup impedances in accelerator components is described. The method was used to measure the longitudinal and transverse beam impedances of the 1 to 2 GeV light source beam pipe. In addition, the technique was used to measure the transverse pickup impedance of a 2 GHz cavity type Schottky signal monitor currently being installed in the FNAL Tevatron. Measurement results for both cases are presented.

  10. FIAS Longitudinal Measurements Modified - More Accurate Cotton Fiber Maturity

    USDA-ARS?s Scientific Manuscript database

    A projected 2-D image of a cotton fiber has large variations in fiber width due to the convolutions along the longitudinal axes. The ratio of the maximum width to the minimum width of a fiber ribbon could be used as a maturity indicator. Another important factor related to cotton maturity is fibers ...

  11. Executive Function in Early Childhood: Longitudinal Measurement Invariance and Developmental Change

    ERIC Educational Resources Information Center

    Willoughby, Michael T.; Wirth, R. J.; Blair, Clancy B.

    2012-01-01

    This study tested the longitudinal measurement invariance and developmental changes of a newly developed battery of executive function (EF) tasks for use in early childhood. The battery was administered in the Family Life Project--a prospective longitudinal study (N = 1,292) of families who were oversampled from low-income and African American…

  12. Executive Function in Early Childhood: Longitudinal Measurement Invariance and Developmental Change

    ERIC Educational Resources Information Center

    Willoughby, Michael T.; Wirth, R. J.; Blair, Clancy B.

    2012-01-01

    This study tested the longitudinal measurement invariance and developmental changes of a newly developed battery of executive function (EF) tasks for use in early childhood. The battery was administered in the Family Life Project--a prospective longitudinal study (N = 1,292) of families who were oversampled from low-income and African American…

  13. Longitudinal measurement of physical activity following kidney transplantation.

    PubMed

    Dontje, M L; de Greef, M H G; Krijnen, W P; Corpeleijn, E; Kok, T; Bakker, S J L; Stolk, R P; van der Schans, C P

    2014-04-01

    The purpose of this longitudinal observational study was to (i) examine the change of daily physical activity in 28 adult kidney transplant recipients over the first 12 months following transplantation; and (ii) to examine the change in metabolic characteristics and renal function. Accelerometer-based daily physical activity and metabolic- and clinical characteristics were measured at six wk (T1), three months (T2), six months (T3) and 12 months (T4) following transplantation. Linear mixed effect analyses showed an increase in steps/d (T1 = 6326 ± 2906; T4 = 7562 ± 3785; F = 3.52; p = 0.02), but one yr after transplantation only 25% achieved the recommended 10 000 steps/d. There was no significant increase in minutes per day spent on moderate-to-vigorous intensity physical activity (T1 = 80.4 ± 63.6; T4 = 93.2 ± 55.1; F = 1.71; p = 0.17). Body mass index increased over time (T1 = 25.4 ± 3.2; T4 = 27.2 ± 3.8; F = 12.62; p < 0.001), mainly due to an increase in fat percentage (T1 = 30.3 ± 8.0; T4 = 34.0 ± 7.9; F = 14.63; p < 0.001). There was no significant change in renal function (F = 0.17; p = 0.92). Although the recipients increased physical activity, the majority did not meet the recommended levels of physical activity after one yr. In addition to the weight gain, this may result in negative health consequences. Therefore, it is important to develop strategies to support kidney transplant recipients to comply with healthy lifestyle recommendations, including regular physical activity.

  14. Multiple imputation for harmonizing longitudinal non-commensurate measures in individual participant data meta-analysis.

    PubMed

    Siddique, Juned; Reiter, Jerome P; Brincks, Ahnalee; Gibbons, Robert D; Crespi, Catherine M; Brown, C Hendricks

    2015-11-20

    There are many advantages to individual participant data meta-analysis for combining data from multiple studies. These advantages include greater power to detect effects, increased sample heterogeneity, and the ability to perform more sophisticated analyses than meta-analyses that rely on published results. However, a fundamental challenge is that it is unlikely that variables of interest are measured the same way in all of the studies to be combined. We propose that this situation can be viewed as a missing data problem in which some outcomes are entirely missing within some trials and use multiple imputation to fill in missing measurements. We apply our method to five longitudinal adolescent depression trials where four studies used one depression measure and the fifth study used a different depression measure. None of the five studies contained both depression measures. We describe a multiple imputation approach for filling in missing depression measures that makes use of external calibration studies in which both depression measures were used. We discuss some practical issues in developing the imputation model including taking into account treatment group and study. We present diagnostics for checking the fit of the imputation model and investigate whether external information is appropriately incorporated into the imputed values. Copyright © 2015 John Wiley & Sons, Ltd.

  15. The Research on Medical Education Outcomes (ROMEO) Registry: Addressing Ethical and Practical Challenges of Using "Bigger," Longitudinal Educational Data.

    PubMed

    Gillespie, Colleen; Zabar, Sondra; Altshuler, Lisa; Fox, Jaclyn; Pusic, Martin; Xu, Junchuan; Kalet, Adina

    2016-05-01

    Efforts to evaluate and optimize the effectiveness of medical education have been limited by the difficulty of designing medical education research. Longitudinal, epidemiological views of educational outcomes can help overcome limitations, but these approaches require "bigger data"-more learners, sources, and time points. The rich data institutions collect on students and residents can be mined, however, ethical and practical barriers to using these data must first be overcome. In 2008, the authors established the Research on Medical Education Outcomes (ROMEO) Registry, an educational data registry modeled after patient registries. New York University School of Medicine students, residents, and fellows provide consent for routinely collected educational, performance, quality improvement, and clinical practice data to be compiled into a deidentified, longitudinal database. As of January 2015, this registry included 1,225 residents and fellows across 12 programs (71% consent rate) and 841 medical students (86% consent rate). Procedures ensuring voluntary informed consent are essential to ethical enrollment and data use. Substantial resources are required to provide access to and manage the data. The registry supports educational scholarship. Seventy-two studies using registry data have been presented or published. These focus on evaluating the curriculum, quality of care, and measurement quality and on assessing needs, competencies, skills development, transfer of skills to practice, remediation patterns, and links between education and patient outcomes. The authors are working to integrate assessment of relevant outcomes into the curriculum, maximize both the quantity and quality of the data, and expand the registry across institutions.

  16. Measuring Practicing Clinicians’ Information Literacy

    PubMed Central

    Barboza, Katherine; Jensen, Ashley E.; Bennett, Katelyn J.; Sherman, Scott E.; Schwartz, Mark D.

    2017-01-01

    Summary Background As healthcare moves towards technology-driven population health management, clinicians must adopt complex digital platforms to access health information and document care. Objectives This study explored information literacy, a set of skills required to effectively navigate population health information systems, among primary care providers in one Veterans’ Affairs (VA) medical center. Methods Information literacy was assessed during an 8-month randomized trial that tested a population health (panel) management intervention. Providers were asked about their use and comfort with two VA digital tools for panel management at baseline, 16 weeks, and post-intervention. An 8-item scale (range 0-40) was used to measure information literacy (Cronbach’s a=0.84). Scores between study arms and provider types were compared using paired t-tests and ANOVAs. Associations between self-reported digital tool use and information literacy were measured via Pearson’s correlations. Results Providers showed moderate levels of information literacy (M= 27.4, SD 6.5). There were no significant differences in mean information literacy between physicians (M=26.4, SD 6.7) and nurses (M=30.5, SD 5.2, p=0.57 for difference), or between intervention (M=28.4, SD 6.5) and control groups (M=25.1, SD 6.2, p=0.12 for difference). Information literacy was correlated with higher rates of self-reported information system usage (r=0.547, p=0.001). Clinicians identified data access, accuracy, and interpretability as potential information literacy barriers. Conclusions While exploratory in nature, cautioning generalizability, the study suggests that measuring and improving clinicians’ information literacy may play a significant role in the implementation and use of digital information tools, as these tools are rapidly being deployed to enhance communication among care teams, improve health care outcomes, and reduce overall costs. PMID:28197620

  17. Measurement of longitudinal relaxation times for spin-decoupled protons.

    NASA Technical Reports Server (NTRS)

    Gerace, M. J.; Kuhlmann, K. F.

    1972-01-01

    Description of an experimental method for the determination of the longitudinal relaxation time for spin-decoupled protons by a modified version of the saturation recovery technique reported by Van Geet and Hume (1965). The described method should facilitate relaxation studies of chemically shifted protons (or fluorines) and can be applied to more complicated spin systems with the aid of triple resonance and noise-decoupling techniques.

  18. Quality measures for nurse practitioner practice evaluation.

    PubMed

    Kleinpell, Ruth; Kapu, April N

    2017-08-01

    Evaluating the impact of nurse practitioner (NP) practice has become a priority area of focus for demonstrating outcomes. A number of quality measures are available to enable practice-specific evaluation of NP roles and initiatives. This article reviews sources of quality measures that can be used to facilitate quantifying the outcomes of NP practice as part of an overall evaluation agenda. National resources and published literature on NP quality measures were reviewed. Various resources and toolkits exist to assist NPs in identifying outcomes of practice using quality measures. The need to demonstrate outcomes of NP practice remains an ongoing priority area regardless of the clinical practice setting. A variety of sources of quality measures exist that can be used to showcase the effect of NP care. The use of quality measures can be effectively integrated into evaluation of NP role and NP-directed initiatives to demonstrate impact, and enhance the conduct of an NP outcomes assessment. The use of organizational, NP-specific, and national-related quality measures can help to showcase how NP care improves the quality, safety, and costs of health care. ©2017 American Association of Nurse Practitioners.

  19. Model selection for marginal regression analysis of longitudinal data with missing observations and covariate measurement error.

    PubMed

    Shen, Chung-Wei; Chen, Yi-Hau

    2015-10-01

    Missing observations and covariate measurement error commonly arise in longitudinal data. However, existing methods for model selection in marginal regression analysis of longitudinal data fail to address the potential bias resulting from these issues. To tackle this problem, we propose a new model selection criterion, the Generalized Longitudinal Information Criterion, which is based on an approximately unbiased estimator for the expected quadratic error of a considered marginal model accounting for both data missingness and covariate measurement error. The simulation results reveal that the proposed method performs quite well in the presence of missing data and covariate measurement error. On the contrary, the naive procedures without taking care of such complexity in data may perform quite poorly. The proposed method is applied to data from the Taiwan Longitudinal Study on Aging to assess the relationship of depression with health and social status in the elderly, accommodating measurement error in the covariate as well as missing observations.

  20. Vibration Measurement on Reticular Lamina and Basilar Membrane at Multiple Longitudinal Locations

    NASA Astrophysics Data System (ADS)

    Chen, Fangyi; Zha, Dingjun; Choudhury, Niloy; Fridberger, Anders; Nuttall, Alfred L.

    2011-11-01

    The longitudinal distribution of the organ of Corti vibration is important for both understanding the energy delivery and the timing of the cochlear amplification. Recent development on low coherence interferomtry technique allows measuring vibration inside the cochlea. The reticular lamina (RL) vibration spectrum demonstrates that RL vibration leads the basilar membrane (BM). This phase lead is consistent with the idea that the active process may lead the BM vibration. In this study, measurements on multiple longitudinal locations demonstrated similar phase lead. Results on this study suggests that there may be another longitudinal coupling mechanism inside the cochlea other than the traveling wave on BM.

  1. Rapid longitudinal relaxation measurement of hyperpolarized 129Xe by a highly sensitive atomic magnetometer

    NASA Astrophysics Data System (ADS)

    Li, Yingying; Wang, Zhiguo; Jin, Shilong; Yuan, Jie; Zhao, Hongchang; Luo, Hui

    2017-02-01

    A fast and accurate determination of longitudinal relaxation time is put forward for hyperpolarized 129Xe. The theoretical framework for the method is developed. Measurement of the longitudinal relaxation time is by the determination of a close-loop response of 129Xe magnetization to the external magnetic fields and is implemented with a highly sensitive Rb magnetometer. The indirect measurement dramatically reduces the time consuming than the conventional inversion-recovery method and is more suitable for the samples with long longitudinal relaxation time.

  2. Eating, feeding, and feeling: emotional responsiveness mediates longitudinal associations between maternal binge eating, feeding practices, and child weight.

    PubMed

    Saltzman, Jaclyn A; Pineros-Leano, Maria; Liechty, Janet M; Bost, Kelly K; Fiese, Barbara H

    2016-08-02

    Although it is known that maternal disordered eating is related to restrictive feeding practices, there is little research exploring mechanisms for this association or its effects on other feeding practices. The purpose of this study was to assess whether maternal emotion responses mediate the association between maternal binge eating (BE) and child feeding practices, in order to identify potential risk factors for feeding practices that influence child weight. This longitudinal observational study included (n = 260) mothers and children from the STRONG Kids Panel Survey. At Wave 1, children were an average of 37 months old (SD = 6.9), and at Wave 2 children were an average of 57 months old (SD = 8.3). Mothers self-reported their frequency of binge eating behavior (Wave 1), responses to children's negative emotions (Wave 1), feeding practices (Wave 1 and Wave 2), and child height and weight were measured at both time points. Using bias-corrected bootstrapping procedures, we tested the hypothesis that longitudinal associations between maternal BE and nonresponsive parent feeding practices would be mediated by parents' unsupportive responses to children's negative emotion. We also tested a serial mediation model positing that maternal BE predicts child body mass index (BMI) percentile change 18-24 months later, indirectly through unsupportive responses to negative emotion and nonresponsive feeding practices. Maternal BE predicted use of more nonresponsive feeding practices (e.g. Emotion Regulation, Restriction for Health, Pressure to Eat, and Food as Reward), indirectly through more Distress responses to children's negative emotions. In the serial mediation model, maternal BE was associated with greater use of Distress responses, which indirectly predicted higher child BMI percentile through Food as Reward feeding practices. These results suggest that maternal eating and emotion responsiveness are important for understanding the interpersonal context of

  3. Measurements of the longitudinal beam parameters in the Fermilab Linac

    SciTech Connect

    Popovic, M.; Junck, K.; Kroc, T.; Mccrory, E.; Ostroumov, P.

    1994-08-01

    The Fermilab Linac Upgrade has increased the energy of the H{sup {minus}} linac from 201 to 401.5 MeV. This is achieved by replacing the last four 201.24 MHz drift-tube linac cavities with seven 804.96 MHz side-coupled cavity modules. Each accelerator module is powered with a 12 MW klystron-based power supply. The purpose of this report is to present a body of representative methods and data used to characterize longitudinal properties of the beam after each accelerating tank and module. These various methods proved useful in the commissioning of the Fermilab Linac Upgrade.

  4. Temporal change in health-related quality of life: a longitudinal study in general practice 1999–2004

    PubMed Central

    Hazell, Michelle L; Morris, Julie A; Linehan, Mary F; Frank, Timothy L

    2009-01-01

    Background In order to assess and plan for changing healthcare needs, the lack of available information regarding temporal changes in the health-related quality of life of a population must be addressed. Aim This paper aims to describe such changes over 5 years in a general population. Design of study Longitudinal postal questionnaire study. Setting UK general practice. Method This was a longitudinal postal questionnaire study in two general practice populations, using the generic instrument EQ-5D to measure health-related quality of life. Individuals were included if they responded to three postal surveys in 1999, 2001, and 2004 and there were three consecutive values of EQ-5Dindex available between 1999 and 2004. Results A total of 2498 subjects were included in the study. After adjustment for potential confounders (including ageing), health-related quality of life declined significantly over the observation period. The change in EQ-5Dindex was from 0.79 to 0.74 and for EQ-5Dvas 76.8 to 73.3 (P for both trends <0.001). Conclusion Health-related quality of life deteriorated in these populations over 5 years. In an era of improvements in mortality, this has important implications for the use of health-related quality of life data in healthcare planning and resource allocation. PMID:19861028

  5. Single-pulse and multipulse longitudinal phase space and temperature measurements of an intense ion beam

    NASA Astrophysics Data System (ADS)

    Coleman, J. E.; Seidl, P. A.; Bieniosek, F. M.; Leitner, M. A.; Lidia, S. M.; Vay, J. L.; Waldron, W. L.; Grote, D. P.; Welch, D. R.

    2012-07-01

    Longitudinal phase space and temperature measurements were conducted on a 2-3μs long, singly charged K+ ion bunch with an ion energy of ˜0.3MeV and current of 30 mA. The principal objective of these experiments was to measure the longitudinal beam dynamics and study the limits of axial compression. The differences between the measured beam energy, longitudinal beam dynamics, and the amplitude and time history of the Marx voltage waveform were all quantified. Longitudinal phase space measurements indicate a slight chromaticity (<1%) in the beam from head to tail. Record low longitudinal temperatures of Tz=2-4×10-2eV were measured for a beam bunch of this intensity with negligible effects from neutralizing the beam space charge with a background plasma. A qualitative comparison of experimental and calculated results are presented, which include time resolved longitudinal distributions, and phase space of the beam at 430 cm.

  6. Cultural measures associated with risky sexual behaviors among Latino youth in Southern California: A longitudinal study

    PubMed Central

    Thing, James P.; Baezconde-Garbanati, Lourdes; Schwartz, Seth J.; Soto, Daniel W.; Unger, Jennifer B.

    2014-01-01

    Context Cultural variables have been associated with sexual risk behaviors among Latino youth, but findings across studies are inconsistent. Methods We analyzed data from a longitudinal study of Latino youth in Southern California followed from 2005–2012 to test whether cultural variables measured in high school were associated with sexual risk behaviors in emerging adulthood, and whether gender moderated these associations. We conducted logistic and ordinal regression analyses. Participants were 995 Latino youth. Results The cultural value of respect for parents was negatively associated with an earlier age at sexual debut (odds ratio, 0.8) and not using a condom at most recent sexual intercourse (0.8). U.S. cultural practices (a measure of acculturation) was positively associated with being sexually active (1.2), having concurrent sexual partners (1.5), and among males only, with a higher number of sexual partners (1.3). Second- and third- generation immigrant youth had lower odds of not using a condom at most recent sexual intercourse when compared to first-generation youth (0.6 and 0.5, respectively). Among females, a stronger endorsement of Latino cultural practices was associated with lower odds of more sexual partners (0.8). By contrast, among males, a stronger endorsement of Latino cultural practices was associated with higher odds of more sexual partners (1.4). Conclusions The cultural measures associated with Latino youth’s sexual behaviors differed across outcomes and by gender. Understanding how culture is related to the sexual behaviors of Latino youth may help inform the development of culturally-sensitive sexual health interventions. PMID:24786352

  7. Longitudinal evaluation of patient-reported outcomes measurement information systems measures in pediatric chronic pain.

    PubMed

    Kashikar-Zuck, Susmita; Carle, Adam; Barnett, Kimberly; Goldschneider, Kenneth R; Sherry, David D; Mara, Constance A; Cunningham, Natoshia; Farrell, Jennifer; Tress, Jenna; DeWitt, Esi Morgan

    2016-02-01

    The Patient-Reported Outcomes Measurement Information System (PROMIS) initiative is a comprehensive strategy by the National Institutes of Health to support the development and validation of precise instruments to assess self-reported health domains across healthy and disease-specific populations. Much progress has been made in instrument development, but there remains a gap in the validation of PROMIS measures for pediatric chronic pain. The purpose of this study was to investigate the construct validity and responsiveness to change of 7 PROMIS domains for the assessment of children (ages: 8-18) with chronic pain--Pain Interference, Fatigue, Anxiety, Depression, Mobility, Upper Extremity Function, and Peer Relationships. The PROMIS measures were administered at the initial visit and 2 follow-up visits at an outpatient chronic pain clinic (CPC; N = 82) and at an intensive amplified musculoskeletal pain day-treatment program (N = 63). Aim 1 examined construct validity of PROMIS measures by comparing them with corresponding "legacy" measures administered as part of usual care in the CPC sample. Aim 2 examined sensitivity to change in both CPC and amplified musculoskeletal pain samples. Longitudinal growth models showed that PROMIS' Pain Interference, Anxiety, Depression, Mobility, Upper Extremity, and Peer Relationship measures and legacy instruments generally performed similarly with slightly steeper slopes of improvement in legacy measures. All 7 PROMIS domains showed responsiveness to change. Results offered initial support for the validity of PROMIS measures in pediatric chronic pain. Further validation with larger and more diverse pediatric pain samples and additional legacy measures would broaden the scope of use of PROMIS in clinical research.

  8. Longitudinal evaluation of Patient Reported Outcomes Measurement Information Systems (PROMIS) measures in pediatric chronic pain

    PubMed Central

    Kashikar-Zuck, Susmita; Carle, Adam; Barnett, Kimberly; Goldschneider, Kenneth R.; Sherry, David D.; Mara, Constance A.; Cunningham, Natoshia; Farrell, Jennifer; Tress, Jenna; DeWitt, Esi Morgan

    2015-01-01

    The Patient Reported Outcomes Measurement Information System (PROMIS) initiative is a comprehensive strategy by the National Institutes of Health to support the development and validation of precise instruments to assess self-reported health domains across healthy and disease-specific populations. Much progress has been made in instrument development but there remains a gap in the validation of PROMIS measures for pediatric chronic pain. The purpose of this study was to investigate the construct validity and responsiveness to change of seven PROMIS domains for the assessment of children (ages 8-18) with chronic pain – Pain Interference, Fatigue, Anxiety, Depression, Mobility, Upper Extremity Function and Peer Relationships. PROMIS measures were administered at the initial visit and two follow-up visits at an outpatient chronic pain clinic (CPC; N=82) and at an intensive amplified pain day-treatment program (AMP; N= 63). Aim 1 examined construct validity of PROMIS measures by comparing them with corresponding “legacy” measures administered as part of usual care in the CPC sample. Aim 2 examined sensitivity to change in both CPC and AMP samples. Longitudinal growth models showed that PROMIS Pain Interference, Anxiety, Depression, Mobility, Upper Extremity and Peer Relationship measures and legacy instruments generally performed similarly with slightly steeper slopes of improvement in legacy measures. All seven PROMIS domains showed responsiveness to change. Results offered initial support for the validity of PROMIS measures in pediatric chronic pain. Further validation with larger and more diverse pediatric pain samples and additional legacy measures would broaden the scope of use of PROMIS in clinical research. PMID:26447704

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

    NASA Astrophysics Data System (ADS)

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

    2010-04-01

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

  10. Selecting a linear mixed model for longitudinal data: repeated measures analysis of variance, covariance pattern model, and growth curve approaches.

    PubMed

    Liu, Siwei; Rovine, Michael J; Molenaar, Peter C M

    2012-03-01

    With increasing popularity, growth curve modeling is more and more often considered as the 1st choice for analyzing longitudinal data. Although the growth curve approach is often a good choice, other modeling strategies may more directly answer questions of interest. It is common to see researchers fit growth curve models without considering alterative modeling strategies. In this article we compare 3 approaches for analyzing longitudinal data: repeated measures analysis of variance, covariance pattern models, and growth curve models. As all are members of the general linear mixed model family, they represent somewhat different assumptions about the way individuals change. These assumptions result in different patterns of covariation among the residuals around the fixed effects. In this article, we first indicate the kinds of data that are appropriately modeled by each and use real data examples to demonstrate possible problems associated with the blanket selection of the growth curve model. We then present a simulation that indicates the utility of Akaike information criterion and Bayesian information criterion in the selection of a proper residual covariance structure. The results cast doubt on the popular practice of automatically using growth curve modeling for longitudinal data without comparing the fit of different models. Finally, we provide some practical advice for assessing mean changes in the presence of correlated data.

  11. Perception and practice of Kangaroo Mother Care after discharge from hospital in Kumasi, Ghana: A longitudinal study

    PubMed Central

    2011-01-01

    Background The practice of Kangaroo Mother Care (KMC) is life saving in babies weighing less than 2000 g. Little is known about mothers' continued unsupervised practice after discharge from hospitals. This study aimed to evaluate its in-hospital and continued practice in the community among mothers of low birth weight (LBW) infants discharged from two hospitals in Kumasi, Ghana. Methods A longitudinal study of 202 mothers and their inpatient LBW neonates was conducted from November 2009 to May 2010. Mothers were interviewed at recruitment to ascertain their knowledge of KMC, and then oriented on its practice. After discharge, the mothers reported at weekly intervals for four follow up visits where data about their perceptions, attitudes and practices of KMC were recorded. A repeated measure logistic regression analysis was done to assess variability in the binary responses at the various reviews visits. Results At recruitment 23 (11.4%, 95%CI: 7.4 to 16.6%) mothers knew about KMC. At discharge 95.5% were willing to continue KMC at home with 93.1% willing to practice at night. 95.5% thought KMC was beneficial to them and 96.0% beneficial to their babies. 98.0% would recommend KMC to other mothers with 71.8% willing to practice KMC outdoors. At first follow up visit 99.5% (181) were still practicing either intermittent or continuous KMC. This proportion did not change significantly over the four weeks (OR: 1.4, 95%CI: 0.6 to 3.3, p-value: 0.333). Over the four weeks, increasingly more mothers practiced KMC at night (OR: 1.7, 95%CI: 1.2 to 2.6, p = 0.005), outside their homes (OR: 2.4, 95%CI: 1.7 to 3.3, p < 0.001) and received spousal help (OR: 1.6, 95%CI: 1.1 to 2.4, p = 0.007). Household chores and potentially negative community perceptions of KMC did not affect its practice with odds of 0.8 (95%CI: 0.5 to 1.2, p = 0.282) and 1.0 (95%CI: 0.6 to 1.7, p = 0.934) respectively. During the follow-up period the neonates gained 23.7 sg (95%CI: 22.6 g to 24.7 g) per day

  12. The predictive validity of selection for entry into postgraduate training in general practice: evidence from three longitudinal studies.

    PubMed

    Patterson, Fiona; Lievens, Filip; Kerrin, Máire; Munro, Neil; Irish, Bill

    2013-11-01

    The selection methodology for UK general practice is designed to accommodate several thousand applicants per year and targets six core attributes identified in a multi-method job-analysis study To evaluate the predictive validity of selection methods for entry into postgraduate training, comprising a clinical problem-solving test, a situational judgement test, and a selection centre. A three-part longitudinal predictive validity study of selection into training for UK general practice. In sample 1, participants were junior doctors applying for training in general practice (n = 6824). In sample 2, participants were GP registrars 1 year into training (n = 196). In sample 3, participants were GP registrars sitting the licensing examination after 3 years, at the end of training (n = 2292). The outcome measures include: assessor ratings of performance in a selection centre comprising job simulation exercises (sample 1); supervisor ratings of trainee job performance 1 year into training (sample 2); and licensing examination results, including an applied knowledge examination and a 12-station clinical skills objective structured clinical examination (OSCE; sample 3). Performance ratings at selection predicted subsequent supervisor ratings of job performance 1 year later. Selection results also significantly predicted performance on both the clinical skills OSCE and applied knowledge examination for licensing at the end of training. In combination, these longitudinal findings provide good evidence of the predictive validity of the selection methods, and are the first reported for entry into postgraduate training. Results show that the best predictor of work performance and training outcomes is a combination of a clinical problem-solving test, a situational judgement test, and a selection centre. Implications for selection methods for all postgraduate specialties are considered.

  13. Are Parenting Practices Associated with the Development of Narcissism? Findings from a Longitudinal Study of Mexican-origin Youth

    PubMed Central

    Wetzel, Eunike; Robins, Richard W.

    2016-01-01

    Narcissism is an important and consequential aspect of personality, yet we know little about its developmental origins. Using data from a longitudinal study of 674 Mexican-origin families, we examined cross-lagged relations between parenting behaviors (warmth, hostility, monitoring) and narcissism (superiority, exploitativeness). Parental hostility at age 12 was associated with higher levels of exploitativeness at age 14, whereas parental monitoring at age 12 was associated with lower levels of exploitativeness at age 14. These effects replicated across three different parenting measures: child reports, spouse reports, and behavioral coding of parent-child interactions. None of the parenting dimensions was related to superiority, suggesting that parenting practices are more strongly related to the maladaptive than the adaptive component of narcissism. PMID:28042186

  14. Are Parenting Practices Associated with the Development of Narcissism? Findings from a Longitudinal Study of Mexican-origin Youth.

    PubMed

    Wetzel, Eunike; Robins, Richard W

    2016-08-01

    Narcissism is an important and consequential aspect of personality, yet we know little about its developmental origins. Using data from a longitudinal study of 674 Mexican-origin families, we examined cross-lagged relations between parenting behaviors (warmth, hostility, monitoring) and narcissism (superiority, exploitativeness). Parental hostility at age 12 was associated with higher levels of exploitativeness at age 14, whereas parental monitoring at age 12 was associated with lower levels of exploitativeness at age 14. These effects replicated across three different parenting measures: child reports, spouse reports, and behavioral coding of parent-child interactions. None of the parenting dimensions was related to superiority, suggesting that parenting practices are more strongly related to the maladaptive than the adaptive component of narcissism.

  15. Reproducibility of anthropometric measurements in children: a longitudinal study.

    PubMed

    Leppik, Aire; Jürimäe, Toivo; Jürimäe, Jaak

    2004-03-01

    The purpose of this study was to establish the reproducibility of a series of anthropometric measures performed twice during one week during a three year period in boys and girls. The subjects of this investigation were 39 children (21 boys and 18 girls), 9-10 year of age at the beginning of the study. Children were measured three times with one year interval. Children were classified by Tanner stage 1-2 during the first measurements, stage 1-3 during the second measurements and stage 1-4 during the third measurements. Body height and weight were measured and BMI calculated. All anthropometric parameters were measured according to the protocol recommended by the International Society for the Advancement of Kinanthropometry (Norton & Olds 1996). Nine skinfolds, 13 girths, eight lengths and eight breadths/lengths were measured. The reproducibility of body height (r = 0.995-0.999), body weight (r = 0.990-0.999) and BMI (r = 0.969-0.999) was very high in boys and girls. The intraclass correlations (ICC), technical errors (TE) and coefficients of variation (CV) were quite different depending on the measurement site of the skinfold thickness. It was surprising that the ICCs were highest and TEs and CVs were lowest during the second year of the measurement. The computed ICC was high, and TE and CV values were quite similar and relatively low in girth, length and breadth/length measurements. It was concluded that the reproducibility of girths, lengths and breadths/lengths in children is very high and the reproducibility of skinfolds is high. Specifically, the reproducibility is very high immediately before puberty in boys and girls.

  16. Genetic linkage analysis of longitudinal hypertension phenotypes using three summary measures

    PubMed Central

    Rao, Shaoqi; Li, Lin; Li, Xia; Moser, Kathy L; Guo, Zheng; Shen, Gongqing; Cannata, Ruth; Zirzow, Erich; Topol, Eric J; Wang, Qing

    2003-01-01

    Background Longitudinal data often have multiple (repeated) measures recorded along a time trajectory. For example, the two cohorts from the Framingham Heart Study (GAW13 Problem 1) contain 21 and 5 repeated measures for hypertension phenotypes as well as epidemiological risk factors, respectively. Direct modelling of a large number of serially and biologically correlated traits in the context of linkage analysis can be prohibitively complex. Alternatively, we may consider using univariate transformation for linkage analysis of longitudinal repeated measures. Results We evaluated the utility of three conventional summary measures (mean, slope, and principal components) for genetic linkage analysis of longitudinal phenotypes by analyzing the chromosome 10 data of the Framingham Heart Study. Except for the temporal slope, all of the summary methods and the multivariate analysis identified the previously reported region, marker GATA64A09, for systolic blood pressure or high blood pressure. Further analysis revealed that this region may harbor gene(s) affecting human blood pressure at multiple stages of life. Conclusion We conclude that mean and principal components are feasible alternatives for genetic linkage analysis of longitudinal phenotypes, but the slope might have a separate genetic basis from that of the original longitudinal phenotypes. PMID:14975092

  17. Practical Considerations for Simultaneous LDV & PIV Measurements

    NASA Astrophysics Data System (ADS)

    Pothos, Stamatios; Boomsma, Aaron; Troolin, Dan

    2016-11-01

    Simultaneous LDV and PIV measurements are useful for validation experiments and when correlating high temporal resolution measurements with large structures of the flow. Performing simultaneous LDV and PIV measurements can be a challenging task due to the differences in temporal and spatial resolution of each technique, as well as requirements for adequate signal. Even so, simultaneous hot-wire and PIV measurements is even more difficult. Unlike hot-wire, LDV is a non-intrusive technique that is unaffected by PIV laser light-sheet heating. Furthermore, hot-wire measurements are adversely affected by seeding particles in the flow required for PIV. In the present study, we discuss several practical considerations for performing simultaneous LDV and PIV measurements. We completed two separate experiments, each with different seeding densities, flow velocities, and working fluids. With these data sets, we studied the effects of temporal and spatial interpolation, up/down sampling, PIV window size and overlap on the simultaneous signals.

  18. Determination of longitudinal aerodynamic derivatives from steady-state measurement of an aircraft

    NASA Technical Reports Server (NTRS)

    Klein, V.

    1977-01-01

    A method for the estimation of aerodynamic derivatives from steady-state symmetric flight data is developed. The derivatives considered are the longitudinal static stability and control derivatives, damping derivatives due to tail, and the derivatives expressing the speed effect on the lift and pitching moment coefficients. The method is an extension of the well known theory of longitudinal static stability and control, and corresponding flight data interpretation. Measured data is assumed in the form of trim curves and lift vs angle of attack. The expressions for the derivative estimates are in the form of algebraic relationships containing known constants, and directly or indirectly measured quantities.

  19. Longitudinal-to-Transverse Mapping for Femtosecond Electron Bunch Length Measurement

    SciTech Connect

    Xiang, Dao; Ding, Yuantao; /SLAC

    2010-08-25

    A longitudinal-to-transverse mapping technique is proposed to measure the length and temporal profile of ultrashort electron bunches. In this scheme a special chicane and a radio-frequency deflecting cavity are used to transform the beam's longitudinal distribution into angular distribution which is further converted to transverse distribution after a parallel-to-point imaging beam line. With this technique, the temporal profile of the electron beam is exactly mapped to the transverse profile. This makes it possible to measure ultrashort electron bunch length with a resolution well beyond 1 femtosecond.

  20. Measurement of longitudinal emittance growth using a laser-induced neutralization method

    SciTech Connect

    Yuan, V.W.; Garcia, R.; Johnson, K.F.; Saadatmand, K.; Sander, O.R.; Sandoval, D.; Shinas, M.

    1991-01-01

    A laser-induced neutralization technique, LINDA, has been used to study the longitudinal emittance of the 5-MeV H{sup {minus}} beam exiting the drift-tube Linac (DTL) of the Los Alamos Accelerator Test Stand (ATS). By using multiple laser intersection points, longitudinal emittance growths over drift distances of 23.6 and 30.6 cm were measured. Subsequently, a beam transport line, which consisted of one arm of a beam funnel, was substituted for the drift space. Measurements show that the elements of the funnel constrain emittance growth while the H{sup {minus}} beam is contained within these transport elements.

  1. Delay interferometric single shot measurement of a petawatt-class laser longitudinal chromatism corrector.

    PubMed

    Rouyer, C; Blanchot, N; Neauport, J; Sauteret, C

    2007-03-05

    In this paper we present a self-referenced interferometric single-shot measurement technique that we use to evaluate the longitudinal chromatism compensation made by a diffractive lens corrector. A diffractive lens with a delay of 1 ps is qualified for a 60 mm beam aperture. This corrector was implemented on the Alisé Nd:glass power chain. We qualify the corrector and the Alisé power chain chromatism, demonstrating the potential of this measuring principle as well as the interest of diffractive lenses to correct longitudinal chromatism of petawatt-class lasers.

  2. A method for longitudinal relaxation time measurement in inhomogeneous fields

    NASA Astrophysics Data System (ADS)

    Chen, Hao; Cai, Shuhui; Chen, Zhong

    2017-08-01

    The spin-lattice relaxation time (T1) plays a crucial role in the study of spin dynamics, signal optimization and data quantification. However, the measurement of chemical shift-specific T1 constants is hampered by the magnetic field inhomogeneity due to poorly shimmed external magnetic fields or intrinsic magnetic susceptibility heterogeneity in samples. In this study, we present a new protocol to determine chemical shift-specific T1 constants in inhomogeneous fields. Based on intermolecular double-quantum coherences, the new method can resolve overlapped peaks in inhomogeneous fields. The measurement results are in consistent with the measurements in homogeneous fields using the conventional method. Since spatial encoding technique is involved, the experimental time for the new method is very close to that for the conventional method. With the aid of T1 knowledge, some concealed information can be exploited by T1 weighting experiments.

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

    PubMed Central

    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 and couple relationship satisfaction at child age 2 years each accounting for a significant portion of the variance in child problem behavior at age 3. Couple relationship satisfaction directly predicted child behavior problems over time. Clinical and research implications are discussed. PMID:20433599

  4. A Joint Model for Longitudinal Measurements and Survival Data in the Presence of Multiple Failure Types

    PubMed Central

    Elashoff, Robert M.; Li, Gang; Li, Ning

    2009-01-01

    Summary In this article we study a joint model for longitudinal measurements and competing risks survival data. Our joint model provides a flexible approach to handle possible nonignorable missing data in the longitudinal measurements due to dropout. It is also an extension of previous joint models with a single failure type, offering a possible way to model informatively censored events as a competing risk. Our model consists of a linear mixed effects submodel for the longitudinal outcome and a proportional cause-specific hazards frailty submodel (Prentice et al., 1978, Biometrics 34, 541-554) for the competing risks survival data, linked together by some latent random effects. We propose to obtain the maximum likelihood estimates of the parameters by an expectation maximization (EM) algorithm and estimate their standard errors using a profile likelihood method. The developed method works well in our simulation studies and is applied to a clinical trial for the scleroderma lung disease. PMID:18162112

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

    PubMed

    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 < .001). In patients with intermittent/persistently 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 < .001) or 3.4-fold (AUC, 0.65; P = .003) for a significant improvement in asthma control and a minimal important increase of 3.5% (AUC, 0.67; P = .004) or 1.8-fold (AUC, 0.63; P = .02) for a significant worsening in asthma control. The association between asthma control and sputum 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.

  6. Bayesian regression analysis of data with random effects covariates from nonlinear longitudinal measurements

    PubMed Central

    De la Cruz, Rolando; Meza, Cristian; Arribas-Gil, Ana; Carroll, Raymond J.

    2016-01-01

    Joint models for a wide class of response variables and longitudinal measurements consist on a mixed-effects model to fit longitudinal trajectories whose random effects enter as covariates in a generalized linear model for the primary response. They provide a useful way to assess association between these two kinds of data, which in clinical studies are often collected jointly on a series of individuals and may help understanding, for instance, the mechanisms of recovery of a certain disease or the efficacy of a given therapy. When a nonlinear mixed-effects model is used to fit the longitudinal trajectories, the existing estimation strategies based on likelihood approximations have been shown to exhibit some computational efficiency problems (De la Cruz et al., 2011). In this article we consider a Bayesian estimation procedure for the joint model with a nonlinear mixed-effects model for the longitudinal data and a generalized linear model for the primary response. The proposed prior structure allows for the implementation of an MCMC sampler. Moreover, we consider that the errors in the longitudinal model may be correlated. We apply our method to the analysis of hormone levels measured at the early stages of pregnancy that can be used to predict normal versus abnormal pregnancy outcomes. We also conduct a simulation study to assess the importance of modelling correlated errors and quantify the consequences of model misspecification. PMID:27274601

  7. Measuring zoo animal welfare: theory and practice.

    PubMed

    Hill, Sonya P; Broom, Donald M

    2009-11-01

    The assessment of animal welfare relates to investigations of how animals try to cope with their environment, and how easy or how difficult it is for them to do so. The use of rigorous scientific methods to assess this has grown over the past few decades, and so our understanding of the needs of animals has improved during this time. Much of the work in the field of animal welfare has been conducted on farm animals, but it is important to consider how the methods and approaches used in assessing farm animal welfare have been, and can be, adapted and applied to the measurement of welfare in animals in other domains, such as in zoos. This is beneficial to our understanding of both the theoretical knowledge, and the practicability of methods. In this article, some of the commonly-used methods for measuring animal welfare will be discussed, as well as some practical considerations in assessing the welfare of zoo animals.

  8. Measuring Longitudinal Gains in Student Learning: A Comparison of Rasch Scoring and Summative Scoring Approaches

    ERIC Educational Resources Information Center

    Zhao, Yue; Huen, Jenny M. Y.; Chan, Y. W.

    2017-01-01

    This study pioneers a Rasch scoring approach and compares it to a conventional summative approach for measuring longitudinal gains in student learning. In this methodological note, our proposed methodology is demonstrated using an example of rating scales in a student survey as part of a higher education outcome assessment. Such assessments have…

  9. Longitudinal emittance measurements in the Booster and AGS during the 2014 RHIC gold run

    SciTech Connect

    Zeno, K.

    2014-08-18

    This note describes longitudinal emittance measurements that were made in the Booster and AGS during the 2014 RHIC Gold run. It also contains an overview of the longitudinal aspects of their setup during this run. Each bunch intended for RHIC is composed of beam from 4 Booster cycles, and there are two of them per AGS cycle. For each of the 8 Booster cycles required to produce the 2 bunches in the AGS, a beam pulse from EVIS is injected into the Booster and captured in four h=4 buckets. Then those bunches are accelerated to a porch where they are merged into 2 bunches and then into 1 bunch.

  10. An Overview of Longitudinal Spin Structure Measurements from JLab

    SciTech Connect

    Sulkosky, Vincent A.

    2013-08-01

    Jefferson Lab is currently one of the facilities leading the investigation of the spin structure of the nucleon. Over the past 15 years, several high precision measurements have been completed, extending our knowledge of the polarized structure functions g{sub 1} and g{sub 2} down to Q{sup 2} = 0.02 GeV{sup 2}. In particular, the low-Q{sup 2} range ({<=} 0.1 GeV{sup 2}) from these data allows us to make a benchmark-check of Chiral Perturbation theory ({chi}PT). Previous results for the moments of the spin structure functions in this region have shown mixed agreement. For {Gamma}{sub 1}, the first moment of g{sub 1}, we find good consistency between data and theory. However, we have seen a surprisingly large discrepancy with {chi}PT calculations for the {delta}{sub LT} spin polarizability on the neutron, which is significantly less sensitive to the {Delta}-resonance contribution. These proceedings will discuss the recent experimental effort at low Q{sup 2} from Jefferson Lab, including a discussion of preliminary results on the neutron. The new results on the neutron still show a sizeable discrepancy between data and theory. However, new calculations show improved agreement with data for some observables. In addition, new proton data for g{sub 2} is also expected to help resolve the disagreement for {delta}{sub LT}.

  11. Prescribed opioids in primary care: cross-sectional and longitudinal analyses of influence of patient and practice characteristics

    PubMed Central

    Foy, Robbie; Leaman, Ben; McCrorie, Carolyn; Petty, Duncan; House, Allan; Bennett, Michael; Carder, Paul; Faulkner, Simon; Glidewell, Liz; West, Robert

    2016-01-01

    Objectives To examine trends in opioid prescribing in primary care, identify patient and general practice characteristics associated with long-term and stronger opioid prescribing, and identify associations with changes in opioid prescribing. Design Trend, cross-sectional and longitudinal analyses of routinely recorded patient data. Setting 111 primary care practices in Leeds and Bradford, UK. Participants We observed 471 828 patient-years in which all patients represented had at least 1 opioid prescription between April 2005 and March 2012. A cross-sectional analysis included 99 847 patients prescribed opioids between April 2011 and March 2012. A longitudinal analysis included 49 065 patient-years between April 2008 and March 2012. We excluded patients with cancer or treated for substance misuse. Main outcome measures Long-term opioid prescribing (4 or more prescriptions within 12 months), stronger opioid prescribing and stepping up to or down from stronger opioids. Results Opioid prescribing in the adult population almost doubled for weaker opioids over 2005–2012 and rose over sixfold for stronger opioids. There was marked variation among general practices in the odds of patients stepping up to stronger opioids compared with those not stepping up (range 0.31–3.36), unexplained by practice-level variables. Stepping up to stronger opioids was most strongly associated with being underweight (adjusted OR 3.26, 1.49 to 7.17), increasing polypharmacy (4.15, 3.26 to 5.29 for 10 or more repeat prescriptions), increasing numbers of primary care appointments (3.04, 2.48 to 3.73 for over 12 appointments in the year) and referrals to specialist pain services (5.17, 4.37 to 6.12). Compared with women under 50 years, men under 50 were less likely to step down once prescribed stronger opioids (0.53, 0.37 to 0.75). Conclusions While clinicians should be alert to patients at risk of escalated opioid prescribing, much prescribing variation may be attributable to

  12. Measuring the Parenting Practices of Custodial Grandmothers

    PubMed Central

    Smith, Gregory C.; Merchant, William; Hayslip, Bert; Hancock, Gregory R.; Strieder, Frederick; Montoro-Rodriguez, Julian

    2015-01-01

    Despite increased interest in parenting among custodial grandmothers (CGM), there is scant research on assessing their parenting practices. With CGMs as informants we examined the factor structure for five self-report scales developed as measures of parental nurturance and discipline with birth parents, and then tested for measurement invariance by grandchildren’s age (4 – <7 versus ≥7 – 12). We also examined concurrent validity for these scales according to the Family Stress Model. Data were from 343 CGMs (M = 58.45, SD = 8.22) enrolled in a randomized clinical trial caring for grandchildren (GC) aged 4 to 12 (M = 7.81, SD = 2.56). Discipline was assessed by three scales from the Parental Behavior Inventory (Consistency, Effective, and Punitive). Nurturance was assessed by the Positive Affect Index and the Supportive Engaged Behavior scale of the Parenting Practice Interview. Confirmatory factor analysis (CFA) revealed that these scales were best represented as five distinct yet covarying factors (RMSEA = .055; SRMR = .07). Follow-up CFAs within each GC age group supported this model, with only few changes suggested by the corresponding diagnostic tests. A model with these changes was then examined for measurement invariance by CG age group, with complete measurement invariance found and all items loading onto their respective factors significantly. The five scales also correlated as expected with indices of CGM psychological distress and GC adjustment. We conclude that the scales examined here can be used meaningfully with CGM as respondents. PMID:26594101

  13. Boiling as household water treatment in Cambodia: a longitudinal study of boiling practice and microbiological effectiveness.

    PubMed

    Brown, Joseph; Sobsey, Mark D

    2012-09-01

    This paper focuses on the consistency of use and microbiological effectiveness of boiling as it is practiced in one study site in peri-urban Cambodia. We followed 60 randomly selected households in Kandal Province over 6 months to collect longitudinal data on water boiling practices and effectiveness in reducing Escherichia coli in household drinking water. Despite > 90% of households reporting that they used boiling as a means of drinking water treatment, an average of only 31% of households had boiled water on hand at follow-up visits, suggesting that actual use may be lower than self-reported use. We collected 369 matched untreated and boiled water samples. Mean reduction of E. coli was 98.5%; 162 samples (44%) of boiled samples were free of E. coli (< 1 colony-forming unit [cfu]/100 mL), and 270 samples (73%) had < 10 cfu/100 mL. Storing boiled water in a covered container was associated with safer product water than storage in an uncovered container.

  14. Boiling as Household Water Treatment in Cambodia: A Longitudinal Study of Boiling Practice and Microbiological Effectiveness

    PubMed Central

    Brown, Joseph; Sobsey, Mark D.

    2012-01-01

    This paper focuses on the consistency of use and microbiological effectiveness of boiling as it is practiced in one study site in peri-urban Cambodia. We followed 60 randomly selected households in Kandal Province over 6 months to collect longitudinal data on water boiling practices and effectiveness in reducing Escherichia coli in household drinking water. Despite > 90% of households reporting that they used boiling as a means of drinking water treatment, an average of only 31% of households had boiled water on hand at follow-up visits, suggesting that actual use may be lower than self-reported use. We collected 369 matched untreated and boiled water samples. Mean reduction of E. coli was 98.5%; 162 samples (44%) of boiled samples were free of E. coli (< 1 colony-forming unit [cfu]/100 mL), and 270 samples (73%) had < 10 cfu/100 mL. Storing boiled water in a covered container was associated with safer product water than storage in an uncovered container. PMID:22826487

  15. BOOK REVIEW: Practical Density Measurement and Hydrometry

    NASA Astrophysics Data System (ADS)

    Gupta, S. V.

    2003-01-01

    Density determinations are very important not only for science and production but also in everyday life, since very often a product is sold by mass but the content of the package is measured by volume (or vice versa) so that the density is needed to convert the values. In production processes the density serves as a measure of mixing ratios and other properties. In science, the determination of Avogadro's constant using silicon single crystals and the potential replacement of the kilogram prototype boost density determination to an extremely low relative uncertainty of 10-7 or less. The book by S V Gupta explains in detail the foundations of any density measurement, namely the volume determination of solid artefacts in terms of the SI base unit of length and the density of water and mercury. Both the history and the actual state of science are reported. For practical density measurements, these chapters contain very useful formulae and tables. Water is treated in detail since it is most widely used as a standard not only for density determination but also to gravimetrically calibrate the capacity of volumetric glassware. Two thirds of the book are devoted to the practical density measurement of solids and liquids, mainly using classical instruments like pycnometers and hydrometers. Methods using free flotation of samples in a liquid without suspension are especially useful for small samples. Also, density determinations of powders and granular or porous samples are explained. Unfortunately, modern density meters of the oscillation type are dealt with in only a few pages. The book is clearly written and easy to understand. It contains a lot of evaluations of formulae that for practical measurements are represented in detailed tables. Methods and measurement procedures are described in detail, including also the calculation of uncertainty. Listings of the advantages and disadvantages of the different methods are very helpful. S V Gupta has written a book that will be

  16. The impact of research education on student nurse attitude, skill and uptake of evidence-based practice: a descriptive longitudinal survey.

    PubMed

    Leach, Matthew J; Hofmeyer, Anne; Bobridge, Amanda

    2016-01-01

    To measure the impact of an undergraduate research education program on the attitude, skill and uptake of evidence-based practice among undergraduate student nurses. The contribution of evidence-based practice to clinical decision-making, quality of care and patient outcomes is well-documented. One approach to improving evidence-based practice uptake in clinical practice is through the provision of undergraduate research education; notwithstanding, the impact of research training on nursing practice is poorly established. Descriptive longitudinal survey. Three hundred and fifty four third-year nursing students enrolled in a Bachelor of Nursing program of a large Australian University were invited. Pre- (Phase 1) and post-completion (Phase 2) of a 16-week research education program, participants were asked to complete the Evidence-Based Practice Attitude and Utilization Survey; an 82-item online questionnaire measuring attitudes, skills and use of evidence-based practice, and barriers and facilitators of evidence-based practice uptake. The survey was completed by 84 (24%) participants in Phase 1 and 33 (39% of Phase 1) participants in Phase 2. Program exposure resulted in a significant improvement in median skill and use subscores, but not median attitude subscore. Participants perceived inadequate skills in the interpretation, appraisal and application of research findings to clinical practice as being less of a barrier to evidence-based practice uptake posteducation, and access to online critical appraisal tools as being significantly more useful in facilitating evidence-based practice uptake posteducation. The findings suggest that undergraduate research education may have a significant effect on nursing students' research skills and use of evidence-based practice, and minimise barriers to evidence-based practice uptake posteducation. Undergraduate research education may play an important role in improving student nurse uptake of evidence-based practice; whether

  17. Longitudinal change in quantitative meniscus measurements in knee osteoarthritis--data from the Osteoarthritis Initiative.

    PubMed

    Bloecker, Katja; Wirth, W; Guermazi, A; Hitzl, W; Hunter, D J; Eckstein, F

    2015-10-01

    We aimed to apply 3D MRI-based measurement technology to studying 2-year change in quantitative measurements of meniscus size and position. Forty-seven knees from the Osteoarthritis Initiative with medial radiographic joint space narrowing had baseline and 2-year follow-up MRIs. Quantitative measures were obtained from manual segmentation of the menisci and tibia using coronal DESSwe images. The standardized response mean (SRM = mean/SD change) was used as measure of sensitivity to longitudinal change. Medial tibial plateau coverage decreased from 34.8% to 29.9% (SRM -0.82; p < 0.001). Change in medial meniscus extrusion in a central image (SRM 0.18) and in the central five slices (SRM 0.22) did not reach significance, but change in extrusion across the entire meniscus (SRM 0.32; p = 0.03) and in the relative area of meniscus extrusion (SRM 0.56; p < 0.001) did. There was a reduction in medial meniscus volume (10%; p < 0.001), width (7%; p < 0.001), and height (2%; p = 0.08); meniscus substance loss was strongest in the posterior (SRM -0.51; p = 0.001) and weakest in the anterior horn (SRM -0.15; p = 0.31). This pilot study reports, for the first time, longitudinal change in quantitative 3D meniscus measurements in knee osteoarthritis. It provides evidence of improved sensitivity to change of 3D measurements compared with single slice analysis. • First longitudinal MRI-based measurements of change of meniscus position and size. • Quantitative longitudinal evaluation of meniscus change in knee osteoarthritis. • Improved sensitivity to change of 3D measurements compared with single slice analysis.

  18. A general joint model for longitudinal measurements and competing risks survival data with heterogeneous random effects

    PubMed Central

    Li, Gang; Elashoff, Robert M.; Pan, Jianxin

    2011-01-01

    This article studies a general joint model for longitudinal measurements and competing risks survival data. The model consists of a linear mixed effects sub-model for the longitudinal outcome, a proportional cause-specific hazards frailty sub-model for the competing risks survival data, and a regression sub-model for the variance–covariance matrix of the multivariate latent random effects based on a modified Cholesky decomposition. The model provides a useful approach to adjust for non-ignorable missing data due to dropout for the longitudinal outcome, enables analysis of the survival outcome with informative censoring and intermittently measured time-dependent covariates, as well as joint analysis of the longitudinal and survival outcomes. Unlike previously studied joint models, our model allows for heterogeneous random covariance matrices. It also offers a framework to assess the homogeneous covariance assumption of existing joint models. A Bayesian MCMC procedure is developed for parameter estimation and inference. Its performances and frequentist properties are investigated using simulations. A real data example is used to illustrate the usefulness of the approach. PMID:20549344

  19. Bayesian joint modeling of longitudinal measurements and time-to-event data using robust distributions.

    PubMed

    Baghfalaki, T; Ganjali, M; Hashemi, R

    2014-01-01

    Distributional assumptions of most of the existing methods for joint modeling of longitudinal measurements and time-to-event data cannot allow incorporation of outlier robustness. In this article, we develop and implement a joint modeling of longitudinal and time-to-event data using some powerful distributions for robust analyzing that are known as normal/independent distributions. These distributions include univariate and multivariate versions of the Student's t, the slash, and the contaminated normal distributions. The proposed model implements a linear mixed effects model under a normal/independent distribution assumption for both random effects and residuals of the longitudinal process. For the time-to-event process a parametric proportional hazard model with a Weibull baseline hazard is used. Also, a Bayesian approach using the Markov-chain Monte Carlo method is adopted for parameter estimation. Some simulation studies are performed to investigate the performance of the proposed method under presence and absence of outliers. Also, the proposed methods are applied for analyzing a real AIDS clinical trial, with the aim of comparing the efficiency and safety of two antiretroviral drugs, where CD4 count measurements are gathered as longitudinal outcomes. In these data, time to death or dropout is considered as the interesting time-to-event outcome variable. Different model structures are developed for analyzing these data sets, where model selection is performed by the deviance information criterion (DIC), expected Akaike information criterion (EAIC), and expected Bayesian information criterion (EBIC).

  20. Measuring Cutaneous Lesions: Trends in Clinical Practice.

    PubMed

    Zhang, Shali; Blalock, Travis W

    2017-08-30

    Knowing the size of a cutaneous lesion can be important for tracking its progression over time, selecting the proper treatment modality, surgical planning, determining prognosis, and accurate billing. However, providers vary in their consistency, accuracy, and methods of measuring cutaneous lesions. To investigate the clinical practices of US dermatologists and dermatologic surgeons regarding how they determine the size of cutaneous lesions. A survey was electronically distributed to members of the American Society for Dermatologic Surgery. Four hundred twenty-six dermatologists completed the online survey. When a lesion is suspected to be malignant, 85% of respondents obtained exact measurements most, if not all, of the time; however, only 8% did for benign lesions. Most providers determined lesion sizes themselves rather than delegating to staff. When performing visual estimation, approximately three-quarters believed that they were accurate to within 1 to 2 mm. The top reasons for obtaining exact measurements were for tracking atypical pigmented lesions, determining treatment pathways, and accurate billing. The majority of respondents believed that lesion size affected management decisions; however, the need for exact measurement remains controversial, particularly for benign lesions. Future studies may investigate whether taking exact versus estimated measurements has an effect on outcomes.

  1. Transverse and Longitudinal Impedance Measurements for the RKTBA Induction Accelerating Gap

    NASA Astrophysics Data System (ADS)

    Eylon, S.; Henestroza, E.; Kim, J.-S.; Houck, T.; Westenskow, G.; Yu, S.

    1997-05-01

    An induction accelerating gap design is being studied for Relativistic Klystron Two Beam Accelerator (RKTBA). The accelerating gap has to satisfy the following major requirements: hold-off of the applied 100 kV accelerating voltage pulse, low transverse impedance for beam break up minimization, low longitudinal impedance at the beam modulation frequency to minimize power absorption. To optimize the gap design various gap geometries, materials and novel insulating techniques will be explored. We shall report on the experimental effort to evaluate the RF properties of the accelerating gaps in a simple pillbox cavity structure. The experimental cavity setup was designed using the AMOS, MAFIA and URMEL numerical codes. We shall present results of the gap cavity transverse impedance measurements using the two wire measuring system. This will include also longitudinal impedance above beam tube cut off frequency using a single wire measuring system.

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

    PubMed

    Hossain, Ahmed; Beyene, Joseph

    2014-01-01

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

  3. Practical and statistical issues in missing data for longitudinal patient-reported outcomes.

    PubMed

    Bell, Melanie L; Fairclough, Diane L

    2014-10-01

    Patient-reported outcomes are increasingly used in health research, including randomized controlled trials and observational studies. However, the validity of results in longitudinal studies can crucially hinge on the handling of missing data. This paper considers the issues of missing data at each stage of research. Practical strategies for minimizing missingness through careful study design and conduct are given. Statistical approaches that are commonly used, but should be avoided, are discussed, including how these methods can yield biased and misleading results. Methods that are valid for data which are missing at random are outlined, including maximum likelihood methods, multiple imputation and extensions to generalized estimating equations: weighted generalized estimating equations, generalized estimating equations with multiple imputation, and doubly robust generalized estimating equations. Finally, we discuss the importance of sensitivity analyses, including the role of missing not at random models, such as pattern mixture, selection, and shared parameter models. We demonstrate many of these concepts with data from a randomized controlled clinical trial on renal cancer patients, and show that the results are dependent on missingness assumptions and the statistical approach.

  4. Longitudinal stratified liquid crystal structures to enable practical spatial light modulators in the terahertz regime

    NASA Astrophysics Data System (ADS)

    Tareki, Abubaker M.; Kim, Wonkyu; Guo, Junpeng; Lindquist, Robert G.

    2016-09-01

    Electro-optic (EO) modulation of the amplitude and phase of electromagnetic waves using liquid crystals (LCs) is commonplace in the optical and infrared regions. This effort has led to commercially available components used in spectral filtering, polarization management, beam steering, transmitters, displays, etc. However, electro-optic techniques have had limited success in the terahertz (THz) region due to several practical design challenges. The growth in applications has led to an interest in the development of a spatial light modulator (SLM) for the terahertz region. In the visible region, the most common SLMs use electro-optic materials such as liquid crystals to spatially modulate a beam. However, this approach to achieve a practical SLM in the terahertz regime has been difficult. The primary barrier for components is the long interaction lengths required to modulate a THz wave. Since the EO modulation depth is directly proportional to the multiplication of the change of permittivity and the ratio of interaction length over wavelength, THz systems with wavelengths ranging from 150 μm to 1mm pose a challenge. To overcome this barrier, longitudinal stratified sub-wavelength liquid crystal structures have been engineered and fabricated. The stratified structures introduce the challenge in the selection and design of the electrodes. By using multiple layers the tunable films can be maintained at manageable thicknesses (25 to 200 μm). The reduced individual film thickness will significantly improve the requisite drive voltage and response time. However, the layered structure with multiple conducting layers adds considerable challenges to the design of the transparent electrode. Both simulation and experimental data will be presented.

  5. Longitudinal beam-transfer-function measurements at the SLC damping rings

    SciTech Connect

    Minty, M.G.; Zimmermann, F.

    1997-05-01

    A longitudinal single-bunch instability in the damping rings at the Stanford Linear Collider (SLC) is thought to contribute to pulse-to-pulse orbit variations in downstream accelerator sections. To better understand this instability, the authors measured the beam phase and bunch length under harmonic modulations of the rf phase and rf voltage. For small phase-modulations the measured response can be explained by interaction of the beam with the cavity fundamental mode. For larger excitations, they observed bifurcation and hysteresis effects. The response to an rf voltage modulation revealed two peaks near the quadrupole-mode frequency, one of which appears to be related to the longitudinal instability. In this paper they present the experimental results.

  6. Longitudinal impedance measurement of an RK-TBA induction accelerating gap

    SciTech Connect

    Eylon, S.; Henestroza, E.; Kim, J.-S.; Houck, T.L.; Westenskow, G.A.; Yu, S.S.

    1997-05-01

    Induction accelerating gap designs are being studied for Relativistic Klystron Two-Beam Accelerator (RK-TBA) applications. The accelerating gap has to satisfy the following major requirements: hold-off of the applied accelerating voltage pulse, low transverse impedance to limit beam breakup, low longitudinal impedance at the beam-modulation frequency to minimize power loss. Various gap geometries, materials and novel insulating techniques were explored to optimize the gap design. We report on the experimental effort to evaluate the rf properties of the accelerating gaps in a simple pillbox cavity structure. The experimental cavity setup was designed using the AMOS, MAFIA and URMEL numerical codes. Longitudinal impedance measurements above beam-tube cut-off frequency using a single-wire measuring system are presented.

  7. Measurement of the beam longitudinal profile in a storage ring bynon-linear laser mixing

    SciTech Connect

    Beche, J.-F.; Byrd, J.; De Santis, S.; Denes, P.; Placidi, M.; Turner, W.; Zolotorev, M.

    2004-05-03

    We report on the development of a new technique for the measurement of the longitudinal beam profile in storage rings. This technique, which has been successfully demonstrated at the Advanced Light Source, mixes the synchrotron radiation with the light from a mode-locked solid state laser oscillator in a non-linear crystal. The up-converted radiation is then detected with a photomultiplier and processed to extract, store, and display the required information. The available choices of laser repetition frequency, pulse width, and phase modulation give a wide range of options for matching the bunch configuration of a particular storage ring. Besides the dynamic measurement of the longitudinal profile of each bunch, the instrument can monitor the evolution of the bunch tails, the presence of untrapped particles and their diffusion into nominally empty RF buckets (''ghostbunches'').

  8. Microwave measurements of energy lost to longitudinal modes by single electron bunches traversing periodic structures

    SciTech Connect

    Wang, J.W.; Loew, G.A.; Weaver, J.N.; Wilson, P.B.

    1981-10-01

    In the design of future linear colliders, it will be important to minimize the loss of beam energy due to the excitation of higher-order modes in the accelerator structure by single bunches of electrons or positrons. This loss is not only detrimental in itself but also gives rise to energy spectrum widening and transverse emittance growth. Microwave measurements made on disk-loaded and alternating-spoke structures to determine the loss to the longitudinal modes are described. In these measurements the Gaussian bunch is simulated by a current pulse of the same shape transmitted through the structure on an axial center conductor. Results to date are presented for the total longitudinal loss parameter per period K in volts per picocoulomb.

  9. Practical guide for validated memristance measurements

    NASA Astrophysics Data System (ADS)

    Du, Nan; Shuai, Yao; Luo, Wenbo; Mayr, Christian; Schüffny, René; Schmidt, Oliver G.; Schmidt, Heidemarie

    2013-02-01

    Chua [IEEE Trans. Circuit Theory 18, 507-519 (1971), 10.1109/TCT.1971.1083337] predicted rather simple charge-flux curves for active and passive memristors (short for memory resistors) and presented active memristor circuit realizations already in the 1970 s. The first passive memristor has been presented in 2008 [D. B. Strukov, G. S. Snider, and D. R. Williams, Nature (London) 453, 80-83 (2008), 10.1038/nature06932]. Typically, memristors are traced in complicated hysteretic current-voltage curves. Therefore, the true essence of many new memristive devices has not been discovered so far. Here, we give a practical guide on how to use normalized charge-flux curves for the prediction of hysteretic current-voltage characteristics of memristors. In the case of memristive BiFeO3 thin film capacitor structures, the normalized charge-flux curves superimpose for different numbers of measurement points Ns and a different measurement time per measurement point Ts. Such normalized charge-flux curves can be used for the prediction of current-voltage characteristics for input signals with arbitrarily chosen Ns and Ts.

  10. Use of Missing Data Methods in Longitudinal Studies: The Persistence of Bad Practices in Developmental Psychology

    ERIC Educational Resources Information Center

    Jelicic, Helena; Phelps, Erin; Lerner, Richard M.

    2009-01-01

    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…

  11. Use of Missing Data Methods in Longitudinal Studies: The Persistence of Bad Practices in Developmental Psychology

    ERIC Educational Resources Information Center

    Jelicic, Helena; Phelps, Erin; Lerner, Richard M.

    2009-01-01

    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…

  12. Discharge rate measurements for Micromegas detectors in the presence of a longitudinal magnetic field

    SciTech Connect

    B. Moreno, S. Aune, J. Ball, G. Charles, A. Giganon, P. Konczykowski, C. Lahonde-Hamdoun, H. Moutarde, S. Procureur, F. Sabatie

    2011-10-01

    We present first discharge rate measurements for Micromegas detectors in the presence of a high longitudinal magnetic field in the GeV kinematical region. Measurements were performed by using two Micromegas detectors and a photon beam impinging a CH{sub 2} target in the Hall B of the Jefferson Laboratory. One detector was equipped with an additional GEM foil, and a reduction of the discharge probability by two orders of magnitude compared to the stand-alone Micromegas was observed. The detectors were p laced in the FROST solenoid providing a longitudinal magnetic field up to 5T. It allowed for precise measurements of the discharge probability dependence with a diffusion-reducing magnetic field. Between 0 and 5T, the discharge probability increased by a factor of 10 for polar angles between 19{degrees} and 34{degrees}. A GEANT4-based simulation developed for sparking rate calculation was calibrated against these data in order to predict the sparking rate in a high longitudinal magnetic field environment. This simulati on is then used to investigate the possible use of Micromegas in the Forward Vertex Tracker (FVT) of the future CLAS12 spectrometer. In the case of the FVT a sparking rate of 1Hz per detector was obtained at the anticipated CLAS12 luminosity.

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

    NASA Astrophysics Data System (ADS)

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

    2016-04-01

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

  14. THz wiggler applied for measurements of electron bunch longitudinal structure in FEL

    NASA Astrophysics Data System (ADS)

    Syresin, E.; Kostromin, S.; Krasilnikov, M.; Makarov, R.; Morozov, N.; Petrov, D.

    2015-01-01

    The infrared undulator manufactured at JINR and installed at FLASH in 2007 is used for longitudinal bunch shape measurements in the range of several tenths of a micrometer. The presented electromagnetic wiggler is intended for generating a narrow-band THz radiation to measure the longitudinal electron bunch structure in FELs with an electron energy of several tens of MeV. This is a planar electromagnetic device with six regular periods, each 30 cm long. The K parameter is varied in the range 0.5-7.12 corresponding to the range B = 0.025-0.356 T of the peak field on the axis. The wiggler is simulated for 19.8 MeV/ c corresponding to the possible FEL option at PITZ. The wavelength range is 126 μm - 5.1 mm for this electron beam momentum. The 3D Opera simulations of the THz wiggler are discussed. A new PITZ photocathode laser system is proposed for the optimized performance of the high-brightness electron beam. The main goal is a production of 3D ellipsoidal electron bunches with homogeneous charge density. The electromagnetic wiggler is supposed to be used for measuring the longitudinal shape of these electron bunches.

  15. Comparison of left ventricular manual versus automated derived longitudinal strain: implications for clinical practice and research.

    PubMed

    Kobayashi, Yukari; Ariyama, Miyuki; Kobayashi, Yuhei; Giraldeau, Genevieve; Fleischman, Dominik; Kozelj, Mirta; Vrtovec, Bojan; Ashley, Euan; Kuznetsova, Tatiana; Schnittger, Ingela; Liang, David; Haddad, Francois

    2016-03-01

    Systolic global longitudinal strain (GLS) is emerging as a useful metric of ventricular function in heart failure and usually assessed using post-processing software. The purpose of this study was to investigate whether longitudinal strain (LS) derived using manual-tracings of ventricular lengths (manual-LS) can be reliable and time efficient when compared to LS obtained by post-processing software (software-LS). Apical 4-chamber view images were retrospectively examined in 50 healthy controls, 100 patients with dilated cardiomyopathy (DCM), and 100 with hypertrophic cardiomyopathy (HCM). We measured endocardial and mid-wall manual-LS and software-LS, using peak of average regional curve [software-LS(a)] and global ventricular lengths [software-LS(l)] according to definition of Lagragian strain. We compared manual-LS and software-LS by using Bland-Altman plot and coefficient of variation (COV). In addition, test-retest was also performed for further assessment of variability in measurements. While manual-LS was obtained in all subjects, software-LS could be obtained in 238 subjects (95%). The time spent for obtaining manual-LS was significantly shorter than for the software-LS (94 ± 39 s vs. 141 ± 79 s, P < 0.001). Overall, manual-LS had an excellent correlation with both software-LS (a) (R(2) = 0.93, P < 0.001) and software-LS(l) (R(2) = 0.84, P < 0.001). The bias (95%CI) between endocardial manual-LS and software-LS(a) was 0.4% [-2.8, 3.6%] in absolute and 3.5% [-17.0, 24.0%] in relative difference while it was 0.4% [-2.5, 3.3%] and 3.4% [-16.2, 23.1%], respectively with software-LS(l). Mid-wall manual-LS and mid-wall software-LS(a) also had good agreement [a bias (95% CI) for absolute value of 0.1% [-2.1, 2.5%] in HCM, and 0.2% [-2.2, 2.6%] in controls]. The COV for manual and software derived LS were below 6%. Test-retest showed good variability for both methods (COVs were 5.8 and 4.7 for endocardial and mid-wall manual-LS, and 4.6 and 4.9 for endocardial and

  16. Modelling of the measured longitudinal piezoelectric coefficient of single ceramic fibres with annular electrodes

    NASA Astrophysics Data System (ADS)

    Pientschke, Christoph; Steinhausen, Ralf; Kern, Sabine; Beige, Horst

    2011-05-01

    A method for the measurement of the longitudinal piezoelectric coefficient d33 of single ceramic fibres with diameters 100-500 µm was recently developed. The voltage was applied using annular electrodes and the resulting displacement was measured by a capacitive method. In this paper, a number of calculations regarding the field distribution and the resulting piezoelectric displacement are presented for a typical lead zirconate titanate (PZT) ceramic. Provided that the fibres are ideally poled in the longitudinal direction, they can be modelled using the finite element method taking into account linear constitutive equations. The deviation of the measured and the actual d33 was modelled for a broad range of heights and diameters of the fibres and different electrode dimensions. The electric field distribution was analysed for typical examples and the influence of the mechanical stress on the measured d33 was studied. For sufficiently long and thin fibres the field distribution of the electric field is quite uniform and the d33 can be measured with high accuracy. Moreover, it was shown that for such fibres the measured piezoelectric coefficient d33 is determined by no other material parameter of the ceramics. The found trends of preferable geometries for the measurement can apparently be transferred to other piezoceramics.

  17. Bayesian nonparametric regression analysis of data with random effects covariates from longitudinal measurements.

    PubMed

    Ryu, Duchwan; Li, Erning; Mallick, Bani K

    2011-06-01

    We consider nonparametric regression analysis in a generalized linear model (GLM) framework for data with covariates that are the subject-specific random effects of longitudinal measurements. The usual assumption that the effects of the longitudinal covariate processes are linear in the GLM may be unrealistic and if this happens it can cast doubt on the inference of observed covariate effects. Allowing the regression functions to be unknown, we propose to apply Bayesian nonparametric methods including cubic smoothing splines or P-splines for the possible nonlinearity and use an additive model in this complex setting. To improve computational efficiency, we propose the use of data-augmentation schemes. The approach allows flexible covariance structures for the random effects and within-subject measurement errors of the longitudinal processes. The posterior model space is explored through a Markov chain Monte Carlo (MCMC) sampler. The proposed methods are illustrated and compared to other approaches, the "naive" approach and the regression calibration, via simulations and by an application that investigates the relationship between obesity in adulthood and childhood growth curves.

  18. Design of piezoelectric probe for measurement of longitudinal and shear components of elastic wave

    NASA Astrophysics Data System (ADS)

    Aoyanagi, Masafumi; Wakatsuki, Naoto; Mizutani, Koichi; Ebihara, Tadashi

    2017-07-01

    We focus on ultrasonic probes for nondestructive tests and evaluation. Transient characteristics of probes are important for nondestructive tests such as the pulse echo method. We previously reported the principle of measurement using a piezoelectric probe with triaxial sensitivities. In the results, it was calculated that the probe could transmit and receive particle displacement which contains normal and tangential components. It was confirmed that the probe had sensitivities in triaxial directions. However, its performance in terms of frequency and transient characteristics has not been evaluated. The purpose of this study is to design a probe by changing its shape to obtain better performance. The transient characteristics of probes in longitudinal and shear driving were evaluated by the inverse Fourier transformation of frequency responses of longitudinal and shear components, using the two-dimensional finite element method. As a result, the sensitivities at the dips of frequency characteristics increased when using our probe compared with those measured using conventional probes in longitudinal and shear driving. Hence, the performance in terms of the frequency response was improved by more than 3 dB under the conditions in this simulation. Also, the pulse width of impulse response was decreased by half compared with that of probes with conventional shapes.

  19. Stress Measurements in Shock-Loaded PBX 9501 with Embedded Longitudinal and Lateral Piezoresistive Ytterbium Gauges

    SciTech Connect

    D.E. Hooks

    2004-12-15

    A series of light gas gun impact experiments were performed with piezoresistive ytterbium (Yb) gauges in longitudinal and lateral orientations embedded in the plastic bonded explosive PBX 9501. These experiments were performed to evaluate the feasibility of using this method to measure lateral stresses and shear strength dynamically in PBX 9501. Ytterbium was chosen as a gauge material based on its high piezoresistance changes at low stress levels. Experiments were performed at longitudinal impact stresses of approximately 0.6 GPa, which is above the yield point of Yb, near the dynamic yield point of PBX 9501, at a level that is comparable with other impact data, and relevant to several multidimensional safety tests. Results show that PBX 9501 does maintain strength throughout compression. Because of poor reproducibility observed in the experiments presented, it appears unlikely that stress extraction from these gauge results would yield an estimate of shear strength at this impact stress with acceptable error.

  20. Longitudinal and Lateral Stress Measurements in NiTi under One-Dimensional Shock Loading

    SciTech Connect

    Meziere, Y. J. E.; Millett, J. C. F.; Bourne, N. K.; Wallwork, A.; Workman, A.

    2006-07-28

    This paper investigates the influence of the impact stress on the magnitude of the shear stress under one-dimensional shock loading. The shear stress is calculated from the measured longitudinal and the lateral stresses. New data in terms of shock stress, particle velocity and shock velocity has been gathered. Results indicate that the lateral stress has a positive dependence on the impact stress. A general decrease of the lateral stress was also observed immediately after the impact, while the longitudinal stress remains constant for the duration of the pulse length. This suggests that the shear strength increases behind the shock front. This decrease had been found to reach a constant value for the specimens impacted at lower stress. A complex mechanism of deformation behind the shock front during loading was thus reveals. This limit, related to the inflexion point noted on the Hugoniot (Us-up), seems to be an effect of the martensitic phase transformation undergoes by the material.

  1. Measurements of fuselage skin strains and displacements near a longitudinal lap joint in a pressurized aircraft

    NASA Technical Reports Server (NTRS)

    Phillips, Edward P.; Britt, Vicki O.

    1991-01-01

    Strains and displacements in a small area near a longitudinal lap joint in the fuselage skin of a B737 aircraft were measured during a pressurization cycle to a differential pressure of 6.2 psi while the aircraft was on the ground. It was found that hoop strains were higher than longitudinal strains at each location; membrane strains in the unreinforced skin were higher than in the joint; membrane strains in the hoop direction, as well as radial displacements, tended to be highest at the mid-bay location between skin reinforcements; significant bending in the hoop direction occurred in the joint and in the skin near the joint, and the bending was unsymmetrically distributed about the stringer at the middle of the joint; and radial displacements were unsymmetrically distributed across the lap joint. The interpretation of the strain gage data for locations on the bonded and riveted lap joint assumed that the joint did not contain disbonded areas.

  2. Measuring Knowledge Integration Learning of Energy Topics: A two-year longitudinal study

    NASA Astrophysics Data System (ADS)

    Liu, Ou Lydia; Ryoo, Kihyun; Linn, Marcia C.; Sato, Elissa; Svihla, Vanessa

    2015-05-01

    Although researchers call for inquiry learning in science, science assessments rarely capture the impact of inquiry instruction. This paper reports on the development and validation of assessments designed to measure middle-school students' progress in gaining integrated understanding of energy while studying an inquiry-oriented curriculum. The assessment development was guided by the knowledge integration framework. Over 2 years of implementation, more than 4,000 students from 4 schools participated in the study, including a cross-sectional and a longitudinal cohort. Results from item response modeling analyses revealed that: (a) the assessments demonstrated satisfactory psychometric properties in terms of reliability and validity; (b) both the cross-sectional and longitudinal cohorts made progress on integrating their understanding energy concepts; and (c) among many factors (e.g. gender, grade, school, and home language) associated with students' science performance, unit implementation was the strongest predictor.

  3. Measuring (subglacial) bedform orientation, length, and longitudinal asymmetry – Method assessment

    PubMed Central

    Brennand, Tracy A.

    2017-01-01

    Geospatial analysis software provides a range of tools that can be used to measure landform morphometry. Often, a metric can be computed with different techniques that may give different results. This study is an assessment of 5 different methods for measuring longitudinal, or streamlined, subglacial bedform morphometry: orientation, length and longitudinal asymmetry, all of which require defining a longitudinal axis. The methods use the standard deviational ellipse (not previously applied in this context), the longest straight line fitting inside the bedform footprint (2 approaches), the minimum-size footprint-bounding rectangle, and Euler’s approximation. We assess how well these methods replicate morphometric data derived from a manually mapped (visually interpreted) longitudinal axis, which, though subjective, is the most typically used reference. A dataset of 100 subglacial bedforms covering the size and shape range of those in the Puget Lowland, Washington, USA is used. For bedforms with elongation > 5, deviations from the reference values are negligible for all methods but Euler’s approximation (length). For bedforms with elongation < 5, most methods had small mean absolute error (MAE) and median absolute deviation (MAD) for all morphometrics and thus can be confidently used to characterize the central tendencies of their distributions. However, some methods are better than others. The least precise methods are the ones based on the longest straight line and Euler’s approximation; using these for statistical dispersion analysis is discouraged. Because the standard deviational ellipse method is relatively shape invariant and closely replicates the reference values, it is the recommended method. Speculatively, this study may also apply to negative-relief, and fluvial and aeolian bedforms. PMID:28319132

  4. Knowledge, Attitudes and Practices Related to Visceral Leishmaniasis in Rural Communities of Amhara State: A Longitudinal Study in Northwest Ethiopia

    PubMed Central

    López-Perea, Noemí; Sordo, Luis; Gadisa, Endalamaw; Cruz, Israel; Hailu, Tsegaye; Moreno, Javier; Aseffa, Abraham; Cañavate, Carmen; Custodio, Estefanía

    2014-01-01

    Background In the northwest of Ethiopia, at the South Gondar region, there was a visceral leishmaniasis (VL) outbreak in 2005, making the disease a public health concern for the regional health authorities ever since. The knowledge on how the population perceives the disease is essential in order to propose successful control strategies. Methodology/Principal findings Two surveys on VL knowledge, attitudes and practices were conducted at the beginning (May 2009) and at the end (February 2011) of a VL longitudinal study carried out in rural communities of Libo Kemkem and Fogera, two districts of the Amhara Regional State. Results showed that VL global knowledge was very low in the area, and that it improved substantially in the period studied. Specifically, from 2009 to 2011, the frequency of proper knowledge regarding VL signs and symptoms increased from 47% to 71% (p<0.0001), knowledge of VL causes increased from 8% to 25% (p<0.0001), and knowledge on VL protection measures from 16% to 55% (p<0.0001). Moreover, the improvement observed in VL knowledge was more marked among the families with no previous history of VL case. Finally, in 2011 more than 90% of the households owned at least an impregnated bed net and had been sprayed, and attitudes towards these and other protective measures were very positive (over 94% acceptance for all of them). Conclusions/Significance In 2009 the level of knowledge regarding VL was very low among the rural population of this area, although it improved substantially in the study period, probably due to the contribution of many actors in the area. VL patients and relatives should be appropriately informed and trained as they may act as successful health community agents. VL risk behavioural patterns are subject to change as attitudes towards protective measures were very positive overall. PMID:24743328

  5. A mixture of hierarchical joint models for longitudinal data with heterogeneity, non-normality, missingness, and covariate measurement error.

    PubMed

    Huang, Yangxin; Yan, Chunning; Yin, Ping; Lu, Meixia

    2016-01-01

    Longitudinal data arise frequently in medical studies and it is a common practice to analyze such complex data with nonlinear mixed-effects (NLME) models. However, the following four issues may be critical in longitudinal data analysis. (i) A homogeneous population assumption for models may be unrealistically obscuring important features of between-subject and within-subject variations; (ii) normality assumption for model errors may not always give robust and reliable results, in particular, if the data exhibit skewness; (iii) the responses may be missing and the missingness may be nonignorable; and (iv) some covariates of interest may often be measured with substantial errors. When carrying out statistical inference in such settings, it is important to account for the effects of these data features; otherwise, erroneous or even misleading results may be produced. Inferential procedures can be complicated dramatically when these four data features arise. In this article, the Bayesian joint modeling approach based on a finite mixture of NLME joint models with skew distributions is developed to study simultaneous impact of these four data features, allowing estimates of both model parameters and class membership probabilities at population and individual levels. A real data example is analyzed to demonstrate the proposed methodologies, and to compare various scenarios-based potential models with different specifications of distributions.

  6. Longitudinal Measures of Serum Albumin and Prealbumin Concentrations in Incident Dialysis Patients: the Comprehensive Dialysis Study

    PubMed Central

    Dalrymple, Lorien S.; Johansen, Kirsten L.; Chertow, Glenn M.; Grimes, Barbara; Anand, Shuchi; McCulloch, Charles E.; Kaysen, George A.

    2012-01-01

    Objective Serum albumin and prealbumin concentrations are strongly associated with the risk of death in patients on dialysis. Our study examined the association among demographic characteristics, body composition, co-morbidities, dialysis modality and access, inflammation and longitudinal measures of albumin and prealbumin in incident dialysis patients. Design, Setting, Subjects and Outcome Measures The Comprehensive Dialysis Study (CDS) is a prospective cohort study of incident dialysis patients; in this report we examined data from 266 Nutrition sub-study participants who donated serum. The independent variables of interest were baseline age, sex, race, Quetélet's (body mass) index, dialysis modality and access, diabetes, heart failure, atherosclerotic vascular disease, serum creatinine, and longitudinal measures of C-reactive protein. The outcomes of interest (dependent variables) were longitudinal measures of albumin and prealbumin concentrations, measured at study entry and every 3 months for one year. Results In multivariable mixed linear models, female sex, peritoneal dialysis, hemodialysis with a catheter, and higher C-reactive protein concentrations were associated with lower serum albumin concentrations, and serum albumin concentrations increased slightly over the year. In comparison, prealbumin concentrations did not significantly change over time; female sex, lower body mass index, diabetes, atherosclerotic vascular disease, and higher C-reactive protein concentrations were associated with lower prealbumin concentrations. Serum creatinine had a curvilinear relation with serum albumin and prealbumin. Conclusions Serum albumin increases early in the course of dialysis whereas prealbumin does not, and the predictors of serum concentrations differ at any given time. Further understanding of mechanisms underlying differences between albumin and prealbumin kinetics in persons on dialysis may lead to an improved approach to the management of protein energy

  7. Reliability of Fiber Tracking Measurements in Diffusion Tensor Imaging for Longitudinal Study

    PubMed Central

    Danielian, Laura E.; Iwata, Nobue K.; Thomasson, David M.; Floeter, Mary Kay

    2009-01-01

    The statistical reliability of diffusion property measurements was evaluated in ten healthy subjects using deterministic fiber tracking to localize tracts affected in motor neuron disease: corticospinal tract (CST), uncinate fasciculus (UNC), and the corpus callosum in its entirety (CC), and its genu (GE), motor (CCM), and splenium (SP) fibers separately. Measurements of fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (λ1), transverse diffusivity (λ⊥), and volume of voxels containing fibers (VV) were obtained within each tract. To assess intra-rater and inter-rater reliability, two raters carried out fiber tracking five times on each scan. Scan-rescan and longitudinal reliability were assessed in a subset of four subjects who had six scans, with two sets of three scans separated by one year. The statistical reliability of repeated measurements was evaluated using intra-class correlation coefficients (ICC) and coefficients of variation (CV). Spatial agreement of tract shape was assessed using the kappa (κ) statistic. Results Repeated same-scan fiber tracking evaluations showed good geometric alignment (intra-rater κ > 0.90, inter-rater κ > 0.76) and reliable diffusion property measurements (intra-rater ICC > 0.92, inter-rater ICC > 0.77). FA, MD, and λ⊥ were highly reliable with repeated scans on different days, up to a year apart (ICC > 0.8). VV also exhibited good reliability, but with higher CVs. We were unable to demonstrate reproducibility of λ1. Longitudinal reliability after one year was improved by averaging measurements from multiple scans at each timepoint. Fiber tracking provides a reliable tool for the longitudinal evaluation of white matter diffusion properties. PMID:19744567

  8. Analysis of the longitudinal and radial resistivity measurements of the nerve trunk.

    PubMed

    Altman, K W; Plonsey, R

    1989-01-01

    Of the many models of peripheral nerve in the literature, essentially all have relied on experimentally derived values for the anisotropic resistivity of the nerve bundle interstitial space. This paper is a comprehensive mathematical analysis of the most referenced experiment for the longitudinal and radial resistivity measurements of the nerve trunk, namely that of Tasaki. For the analysis of the longitudinal measurements we introduce intracellular as well as interstitial current pathways (not considered by Tasaki). For the radial measurement the resistivity is expected to depend on the geometric packing of fibers within the trunk. Since Tasaki's paper did not include a histological examination of the nerve trunk these measurements are difficult to evaluate. However, our analysis indicates the importance of including the above factors, in addition to the epineurial (and perineurial) sheath as a resistive pathway. Our mathematical analysis supports the experimental measurements and confirms an assumed nerve trunk composition with theoretically derived values for the interstitial resistivities. It is therefore concluded that, at present, an appropriate procedure in determining resistivity values for use in modeling is to derive these values for an idealized nerve bundle based on the microscopic (electrolytic) resistivity of the interstitial medium.

  9. Concordance correlation coefficients estimated by generalized estimating equations and variance components for longitudinal repeated measurements.

    PubMed

    Tsai, Miao-Yu

    2017-04-15

    The concordance correlation coefficient (CCC) is a commonly accepted measure of agreement between two observers for continuous responses. This paper proposes a generalized estimating equations (GEE) approach allowing dependency between repeated measurements over time to assess intra-agreement for each observer and inter- and total agreement among multiple observers simultaneously. Furthermore, the indices of intra-, inter-, and total agreement through variance components (VC) from an extended three-way linear mixed model (LMM) are also developed with consideration of the correlation structure of longitudinal repeated measurements. Simulation studies are conducted to compare the performance of the GEE and VC approaches for repeated measurements from longitudinal data. An application of optometric conformity study is used for illustration. In conclusion, the GEE approach allowing flexibility in model assumptions and correlation structures of repeated measurements gives satisfactory results with small mean square errors and nominal 95% coverage rates for large data sets, and when the assumption of the relationship between variances and covariances for the extended three-way LMM holds, the VC approach performs outstandingly well for all sample sizes. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  10. Reference ranges for 2-dimensional sonographic lung measurements in healthy fetuses: a longitudinal study.

    PubMed

    Britto, Ingrid Schwach Werneck; Araujo Júnior, Edward; Sangi-Haghpeykar, Haleh; Bussamra, Luiz Cláudio Silva; Deter, Russell L; Belfort, Michael A; Lee, Wesley; Ruano, Rodrigo

    2014-11-01

    The purpose of this study was to establish reference ranges for 2-dimensional sonographic measurements of fetal lungs from longitudinal data. A total of 214 fetal lung measurements were longitudinally evaluated in 62 healthy fetuses between 20 and 36 weeks' menstrual age. Both right and left lung areas were measured in the heart 4-chamber view using lung area tracing and axis diameter methods. Multilevel modeling was used to evaluate the expected values and variability with respect to menstrual age and to generate reference ranges for the lung area, lung-to-head ratio, quantitative lung index, and observed-to-expected lung-to-head ratio for both lungs. The expected values varied with menstrual age for all parameters. Variance was menstrual age dependent for all parameters except the longest diameter area measurements and their lung-to-head ratios. Models are presented for expected 2-dimensional sonographic lung size parameters and their variance as a function of menstrual age. These data have been used to generate age-specific reference ranges for both measurements and indices. © 2014 by the American Institute of Ultrasound in Medicine.

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

    PubMed

    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.

  12. Measurements of the longitudinal shower development with the Pierre Auger Observatory

    NASA Astrophysics Data System (ADS)

    de Souza, V.

    2013-06-01

    In this work we explain how the Pierre Auger Observatory measures and reconstructs the longitudinal development of air showers. The measurement of the energy deposit in the atmosphere by the detection of the emitted fluorescence light is going to be briefly reviewed and the reconstruction procedure is going to be explained in detail. The two main outputs of this analysis are: a) the depth at which the shower reaches its maximum (Xmax) and b) the shower energy. In this work we concentrate on the analysis techniques developed with the aim to evaluate the unbiased Xmax distributions. We show how using measured events it is possible to estimate the range of the true Xmax distribution. Then we select events with geometries that allow an unbiased measurement of Xmax anywhere along its estimated range. The analysis procedure explained here is a fundamental step in the measurements of cosmic ray mass composition and proton-air cross section.

  13. Longitudinal measurement and hierarchical classification framework for the prediction of Alzheimer's disease.

    PubMed

    Huang, Meiyan; Yang, Wei; Feng, Qianjin; Chen, Wufan

    2017-01-12

    Accurate prediction of Alzheimer's disease (AD) is important for the early diagnosis and treatment of this condition. Mild cognitive impairment (MCI) is an early stage of AD. Therefore, patients with MCI who are at high risk of fully developing AD should be identified to accurately predict AD. However, the relationship between brain images and AD is difficult to construct because of the complex characteristics of neuroimaging data. To address this problem, we present a longitudinal measurement of MCI brain images and a hierarchical classification method for AD prediction. Longitudinal images obtained from individuals with MCI were investigated to acquire important information on the longitudinal changes, which can be used to classify MCI subjects as either MCI conversion (MCIc) or MCI non-conversion (MCInc) individuals. Moreover, a hierarchical framework was introduced to the classifier to manage high feature dimensionality issues and incorporate spatial information for improving the prediction accuracy. The proposed method was evaluated using 131 patients with MCI (70 MCIc and 61 MCInc) based on MRI scans taken at different time points. Results showed that the proposed method achieved 79.4% accuracy for the classification of MCIc versus MCInc, thereby demonstrating very promising performance for AD prediction.

  14. Longitudinal measurement and hierarchical classification framework for the prediction of Alzheimer’s disease

    PubMed Central

    Huang, Meiyan; Yang, Wei; Feng, Qianjin; Chen, Wufan; Weiner, Michael W.; Aisen, Paul; Petersen, Ronald; Jack, Clifford R.; Jagust, William; Trojanowki, John Q.; Toga, Arthur W.; Beckett, Laurel; Green, Robert C.; Saykin, Andrew J.; Morris, John; Shaw, Leslie M.; Kaye, Jeffrey; Quinn, Joseph; Silbert, Lisa; Lind, Betty; Carter, Raina; Dolen, Sara; Schneider, Lon S.; Pawluczyk, Sonia; Beccera, Mauricio; Teodoro, Liberty; Spann, Bryan M.; Brewer, James; Vanderswag, Helen; Fleisher, Adam; Heidebrink, Judith L.; Lord, Joanne L.; Mason, Sara S.; Albers, Colleen S.; Knopman, David; Johnson, Kris; Doody, Rachelle S.; Villanueva-Meyer, Javier; Chowdhury, Munir; Rountree, Susan; Dang, Mimi; Stern, Yaakov; Honig, Lawrence S.; Bell, Karen L.; Ances, Beau; Morris, John C.; Carroll, Maria; Creech, Mary L.; Franklin, Erin; Mintun, Mark A.; Schneider, Stacy; Oliver, Angela; Marson, Daniel; Griffith, Randall; Clark, David; Geldmacher, David; Brockington, John; Roberson, Erik; Love, Marissa Natelson; Grossman, Hillel; Mitsis, Effie; Shah, Raj C.; deToledo-Morrell, Leyla; Duara, Ranjan; Varon, Daniel; Greig, Maria T.; Roberts, Peggy; Albert, Marilyn; Onyike, Chiadi; D’Agostino, Daniel; Kielb, Stephanie; Galvin, James E.; Cerbone, Brittany; Michel, Christina A.; Pogorelec, Dana M.; Rusinek, Henry; de Leon, Mony J.; Glodzik, Lidia; De Santi, Susan; Doraiswamy, P. Murali; Petrella, Jeffrey R.; Borges-Neto, Salvador; Wong, Terence Z.; Coleman, Edward; Smith, Charles D.; Jicha, Greg; Hardy, Peter; Sinha, Partha; Oates, Elizabeth; Conrad, Gary; Porsteinsson, Anton P.; Goldstein, Bonnie S.; Martin, Kim; Makino, Kelly M.; Ismail, M. Saleem; Brand, Connie; Mulnard, Ruth A.; Thai, Gaby; Mc-Adams-Ortiz, Catherine; Womack, Kyle; Mathews, Dana; Quiceno, Mary; Levey, Allan I.; Lah, James J.; Cellar, Janet S.; Burns, Jeffrey M.; Swerdlow, Russell H.; Brooks, William M.; Apostolova, Liana; Tingus, Kathleen; Woo, Ellen; Silverman, Daniel H. S.; Lu, Po H.; Bartzokis, George; Graff-Radford, Neill R.; Parfitt, Francine; Kendall, Tracy; Johnson, Heather; Farlow, Martin R.; Hake, Ann Marie; Matthews, Brandy R.; Brosch, Jared R.; Herring, Scott; Hunt, Cynthia; van Dyck, Christopher H.; Carson, Richard E.; MacAvoy, Martha G.; Varma, Pradeep; Chertkow, Howard; Bergman, Howard; Hosein, Chris; Black, Sandra; Stefanovic, Bojana; Caldwell, Curtis; Hsiung, Ging-Yuek Robin; Feldman, Howard; Mudge, Benita; Assaly, Michele; Finger, Elizabeth; Pasternack, Stephen; Rachisky, Irina; Trost, Dick; Kertesz, Andrew; Bernick, Charles; Munic, Donna; Mesulam, Marek Marsel; Lipowski, Kristine; Weintraub, Sandra; Bonakdarpour, Borna; Kerwin, Diana; Wu, Chuang-Kuo; Johnson, Nancy; Sadowsky, Carl; Villena, Teresa; Turner, Raymond Scott; Johnson, Kathleen; Reynolds, Brigid; Sperling, Reisa A.; Johnson, Keith A.; Marshall, Gad; Yesavage, Jerome; Taylor, Joy L.; Lane, Barton; Rosen, Allyson; Tinklenberg, Jared; Sabbagh, Marwan N.; Belden, Christine M.; Jacobson, Sandra A.; Sirrel, Sherye A.; Kowall, Neil; Killiany, Ronald; Budson, Andrew E.; Norbash, Alexander; Johnson, Patricia Lynn; Obisesan, Thomas O.; Wolday, Saba; Allard, Joanne; Lerner, Alan; Ogrocki, Paula; Tatsuoka, Curtis; Fatica, Parianne; Fletcher, Evan; Maillard, Pauline; Olichney, John; DeCarli, Charles; Carmichael, Owen; Kittur, Smita; Borrie, Michael; Lee, T-Y; Bartha, Rob; Johnson, Sterling; Asthana, Sanjay; Carlsson, Cynthia M.; Potkin, Steven G.; Preda, Adrian; Nguyen, Dana; Tariot, Pierre; Burke, Anna; Trncic, Nadira; Fleisher, Adam; Reeder, Stephanie; Bates, Vernice; Capote, Horacio; Rainka, Michelle; Scharre, Douglas W.; Kataki, Maria; Adeli, Anahita; Zimmerman, Earl A.; Celmins, Dzintra; Brown, Alice D.; Pearlson, Godfrey D.; Blank, Karen; Anderson, Karen; Flashman, Laura A.; Seltzer, Marc; Hynes, Mary L.; Santulli, Robert B.; Sink, Kaycee M.; Gordineer, Leslie; Williamson, Jeff D.; Garg, Pradeep; Watkins, Franklin; Ott, Brian R.; Querfurth, Henry; Tremont, Geoffrey; Salloway, Stephen; Malloy, Paul; Correia, Stephen; Rosen, Howard J.; Miller, Bruce L.; Perry, David; Mintzer, Jacobo; Spicer, Kenneth; Bachman, David; Pomara, Nunzio; Hernando, Raymundo; Sarrael, Antero; Relkin, Norman; Chaing, Gloria; Lin, Michael; Ravdin, Lisa; Smith, Amanda; Raj, Balebail Ashok; Fargher, Kristin

    2017-01-01

    Accurate prediction of Alzheimer’s disease (AD) is important for the early diagnosis and treatment of this condition. Mild cognitive impairment (MCI) is an early stage of AD. Therefore, patients with MCI who are at high risk of fully developing AD should be identified to accurately predict AD. However, the relationship between brain images and AD is difficult to construct because of the complex characteristics of neuroimaging data. To address this problem, we present a longitudinal measurement of MCI brain images and a hierarchical classification method for AD prediction. Longitudinal images obtained from individuals with MCI were investigated to acquire important information on the longitudinal changes, which can be used to classify MCI subjects as either MCI conversion (MCIc) or MCI non-conversion (MCInc) individuals. Moreover, a hierarchical framework was introduced to the classifier to manage high feature dimensionality issues and incorporate spatial information for improving the prediction accuracy. The proposed method was evaluated using 131 patients with MCI (70 MCIc and 61 MCInc) based on MRI scans taken at different time points. Results showed that the proposed method achieved 79.4% accuracy for the classification of MCIc versus MCInc, thereby demonstrating very promising performance for AD prediction. PMID:28079104

  15. Longitudinal measures of serum albumin and prealbumin concentrations in incident dialysis patients: the comprehensive dialysis study.

    PubMed

    Dalrymple, Lorien S; Johansen, Kirsten L; Chertow, Glenn M; Grimes, Barbara; Anand, Shuchi; McCulloch, Charles E; Kaysen, George A

    2013-03-01

    Serum albumin and prealbumin concentrations are strongly associated with the risk of death in dialysis patients. Our study examined the association among demographic characteristics, body composition, comorbidities, dialysis modality and access, inflammation, and longitudinal measures of albumin and prealbumin concentrations in incident dialysis patients. DESIGN, SETTING, SUBJECTS, AND OUTCOME MEASURES: The Comprehensive Dialysis Study is a prospective cohort study of incident dialysis patients; in this report, we examined the data from 266 Nutrition substudy participants who donated serum. The independent variables of interest were baseline age, sex, race, Quetélet's (body mass) index, dialysis modality and access, diabetes, heart failure, atherosclerotic vascular disease, serum creatinine level, and longitudinal measures of C-reactive protein. The outcomes of interest (dependent variables) were longitudinal measures of albumin and prealbumin concentrations, recorded at study entry and thereafter every 3 months for 1 year. In multivariable mixed linear models, female sex, peritoneal dialysis, hemodialysis with a catheter, and higher C-reactive protein concentrations were associated with lower serum albumin concentrations, and serum albumin concentrations increased slightly over the year. In comparison, prealbumin concentrations did not significantly change over time; female sex, lower body mass index, diabetes, atherosclerotic vascular disease, and higher C-reactive protein concentrations were associated with lower prealbumin concentrations. Serum creatinine had a curvilinear relation with serum albumin and prealbumin. Serum albumin level increases early in the course of dialysis, whereas prealbumin level does not, and the predictors of serum concentrations differ at any given time. Further understanding of the mechanisms underlying differences between albumin and prealbumin kinetics in dialysis patients may lead to an improved approach to the management of

  16. Measuring flow-mediated dilation through transverse and longitudinal imaging: comparison and validation of methods

    NASA Astrophysics Data System (ADS)

    Stroz, Marianne J.; Fenster, Aaron

    2010-11-01

    Three-dimensional ultrasound images (3DUS), having two spatial and one temporal dimension, were taken of the brachial artery during baseline conditions, in the transverse and longitudinal planes. The transverse images were analyzed by three different techniques used to quantify flow-mediated dilation (FMD): (1) measuring vessel area manually (TIMA), (2) measuring vessel area semi-automatically (TISA) and (3) measuring vessel diameter (TID). The inter- and intra-observer variability and transducer repositioning variability of each method were compared to each other and to the variability of measurements taken using the traditional method of measuring vessel FMD through measuring vessel diameter on longitudinal images (LID). The percent coefficient-of-variation describing the inter-observer variability (COVinter) was similar for the methods, indicating that each method was equally reproducible by the different observers. The percent coefficient-of-variation describing the intra-observer variability (COVintra) and the smallest detectable percent change in diameter (Δdintra) for each method indicated that TID was the most precise at measuring vessel diameter, and could measure the smallest changes in diameter between successive measurements (COVintra = 0.31%, Δdintra = 0.87%). LID performed the poorest (COVintra = 0.57%, Δdintra = 1.59%). The percent coefficient-of-variation describing transducer repositioning (COVrep) and the smallest detectable percent change in FMD over time (ΔFMD) for each method indicated that TIMA was the most reproducible method (COVrep = 2.35%, ΔFMD = 6.52%) closely followed by TISA. TID performed the poorest (COVrep = 5.37%, ΔFMD = 14.89%). TIMA and TISA were found not to be statistically different so we suggest TISA as the method of choice to maximize reproducibility between measurements over time, as it is faster and simpler to perform. In each experiment it was clear that transverse imaging introduced equal or less variability into

  17. Measuring flow-mediated dilation through transverse and longitudinal imaging: comparison and validation of methods.

    PubMed

    Stroz, Marianne J; Fenster, Aaron

    2010-11-07

    Three-dimensional ultrasound images (3DUS), having two spatial and one temporal dimension, were taken of the brachial artery during baseline conditions, in the transverse and longitudinal planes. The transverse images were analyzed by three different techniques used to quantify flow-mediated dilation (FMD): (1) measuring vessel area manually (TIMA), (2) measuring vessel area semi-automatically (TISA) and (3) measuring vessel diameter (TID). The inter- and intra-observer variability and transducer repositioning variability of each method were compared to each other and to the variability of measurements taken using the traditional method of measuring vessel FMD through measuring vessel diameter on longitudinal images (LID). The percent coefficient-of-variation describing the inter-observer variability (COV(inter)) was similar for the methods, indicating that each method was equally reproducible by the different observers. The percent coefficient-of-variation describing the intra-observer variability (COV(intra)) and the smallest detectable percent change in diameter (Δd(intra)) for each method indicated that TID was the most precise at measuring vessel diameter, and could measure the smallest changes in diameter between successive measurements (COV(intra) = 0.31%, Δd(intra) = 0.87%). LID performed the poorest (COV(intra) = 0.57%, Δd(intra) = 1.59%). The percent coefficient-of-variation describing transducer repositioning (COV(rep)) and the smallest detectable percent change in FMD over time (ΔFMD) for each method indicated that TIMA was the most reproducible method (COV(rep) = 2.35%, ΔFMD = 6.52%) closely followed by TISA. TID performed the poorest (COV(rep) = 5.37%, ΔFMD = 14.89%). TIMA and TISA were found not to be statistically different so we suggest TISA as the method of choice to maximize reproducibility between measurements over time, as it is faster and simpler to perform. In each experiment it was clear that transverse imaging introduced equal or less

  18. Clinicians' perceptions of implementation extensiveness of 100% tobacco free practices: a longitudinal study of New York state.

    PubMed

    Eby, Lillian T de Tormes; Laschober, Tanja C

    2014-01-01

    In 2008, the state of New York required substance use disorder treatment organizations to be 100% tobacco-free. This longitudinal study examined clinicians' perceptions of the implementation extensiveness of the tobacco-free practices approximately 10-12 months (Time 1) and 20-24 months (Time 2) post regulation and investigated whether clinicians' commitment to change and use of provided resources at Time 1 predicts perceptions of implementation extensiveness at Time 2. Clinicians (N = 287) noted a mean implementation of 5.60 patient practices (0-10 scale), 2.33 visitor practices (0-8 scale), and 6.66 employee practices (0-12 scale) at Time 1. At Time 2, clinicians perceived a mean implementation of 5.95 patient practices (no increase from Time 1), 2.89 visitor practices (increase from Time 1), and 7.12 employee practices (no increase from Time 1). Commitment to change and use of resources positively predicted perceived implementation extensiveness of visitor and employee practices. The use of resources positively predicted implementation for patient practices.

  19. Clinicians’ Perceptions of Implementation Extensiveness of 100% Tobacco Free Practices: A Longitudinal Study of New York State1

    PubMed Central

    de Tormes Eby, Lillian Turner; Laschober, Tanja C.

    2013-01-01

    In 2008, New York State required substance use disorder treatment organizations to be 100% tobacco-free. This longitudinal study examined clinicians’ perceptions of the implementation extensiveness of the tobacco-free practices approximately 10–12 months (Time 1) and 20–24 months (Time 2) post regulation and investigated whether clinicians’ commitment to change and use of provided resources at Time 1 predicts perceptions of implementation extensiveness at Time 2. Clinicians (N = 287) noted a mean implementation of 5.60 patient practices (0–10 scale), 2.33 visitor practices (0–8 scale), and 6.66 employee practices (0–12 scale) at Time 1. At Time 2, clinicians perceived a mean implementation of 5.95 patient practices (no increase from Time 1), 2.89 visitor practices (increase from Time 1), and 7.12 employee practices (no increase from Time 1). Commitment to change and use of resources positively predicted perceived implementation extensiveness of visitor and employee practices. The use of resources positively predicted implementation for patient practices. PMID:23430285

  20. 38 CFR 21.4275 - Practical training courses; measurement.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ....C. 3688(b); Pub. L. 99-576) (b) Nursing courses. (1) Courses for the objective of registered nurse or registered professional nurse will be measured on the basis of credit hours or clock hours of... practical nurse, practical trained nurse, or licensed practical nurse will be measured on credit hours...

  1. 38 CFR 21.7674 - Measurement of practical training courses.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    .... (1) Courses for the objective of registered nurse or registered professional nurse will be measured...) Courses offered by institutions of higher learning which lead to the objective of practical nurse, practical trained nurse, or licensed practical nurse will be measured on credit hours or clock hours...

  2. 38 CFR 21.7674 - Measurement of practical training courses.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    .... (1) Courses for the objective of registered nurse or registered professional nurse will be measured...) Courses offered by institutions of higher learning which lead to the objective of practical nurse, practical trained nurse, or licensed practical nurse will be measured on credit hours or clock hours of...

  3. Longitudinal impedance of capacitive pick-up electrodes: Calculations and comparison with measurements

    SciTech Connect

    Blaskiewicz, M.; Luccio, A.; Ratti, A.; Shea, T.J.

    1992-01-01

    In order to obtain high sensitivity over a broad frequency range, split cylinder capacitive pick-up electrodes have been adopted as the beam position monitors (BPMs) for the AGS booster. Numerical simulation and prototype measurements have been employed to find the coupling impedance of a BPM. The impedance was calculated using the MAFIA computer codes, and measurements were made using a coaxial wire. We found that the measured impedance depended strongly on external electronics, which could not be modeled using the computer code. Additionally, the calculated impedance is a function of beam velocity, which was not studied in the measurements. Only by using both could a reliable bound on the shunt impedance be obtained. We find that the longitudinal impedance of the BPMs is negligible for normal operating conditions in the booster.

  4. Longitudinal impedance of capacitive pick-up electrodes: Calculations and comparison with measurements

    SciTech Connect

    Blaskiewicz, M.; Luccio, A.; Ratti, A.; Shea, T.J.

    1992-09-01

    In order to obtain high sensitivity over a broad frequency range, split cylinder capacitive pick-up electrodes have been adopted as the beam position monitors (BPMs) for the AGS booster. Numerical simulation and prototype measurements have been employed to find the coupling impedance of a BPM. The impedance was calculated using the MAFIA computer codes, and measurements were made using a coaxial wire. We found that the measured impedance depended strongly on external electronics, which could not be modeled using the computer code. Additionally, the calculated impedance is a function of beam velocity, which was not studied in the measurements. Only by using both could a reliable bound on the shunt impedance be obtained. We find that the longitudinal impedance of the BPMs is negligible for normal operating conditions in the booster.

  5. Measurement of the Longitudinal Structure Function from ep Collisions with the H1 Detector at HERA

    SciTech Connect

    Raicevic, N.

    2007-04-23

    The longitudinal structure function, FL, is identically zero in lowest order QCD, but due to gluon radiation gets a non-zero value in perturbative QCD. Measurements of FL can thus provide constraints on the gluon density in the proton which are complementary to that obtained from the scaling violations of structure function F2. In this report indirect measurements of FL from ep collisions with the H1 detector at HERA accelerator, at center-of-mass energy of 320 Gev, are summarised. For the measurement of the FL it is essential to reach maximum possible values of inelasticity y. Experimental techniques which can provide precise measurements in this region will also be discussed.

  6. Quantitative muscle strength assessment in duchenne muscular dystrophy: longitudinal study and correlation with functional measures

    PubMed Central

    2012-01-01

    Background The aim of this study was to perform a longitudinal assessment using Quantitative Muscle Testing (QMT) in a cohort of ambulant boys affected by Duchenne muscular dystrophy (DMD) and to correlate the results of QMT with functional measures. This study is to date the most thorough long-term evaluation of QMT in a cohort of DMD patients correlated with other measures, such as the North Star Ambulatory Assessment (NSAA) or thee 6-min walk test (6MWT). Methods This is a single centre, prospective, non-randomised, study assessing QMT using the Kin Com® 125 machine in a study cohort of 28 ambulant DMD boys, aged 5 to 12 years. This cohort was assessed longitudinally over a 12 months period of time with 3 monthly assessments for QMT and with assessment of functional abilities, using the NSAA and the 6MWT at baseline and at 12 months only. QMT was also used in a control group of 13 healthy age-matched boys examined at baseline and at 12 months. Results There was an increase in QMT over 12 months in boys below the age of 7.5 years while in boys above the age of 7.5 years, QMT showed a significant decrease. All the average one-year changes were significantly different than those experienced by healthy controls. We also found a good correlation between quantitative tests and the other measures that was more obvious in the stronger children. Conclusion Our longitudinal data using QMT in a cohort of DMD patients suggest that this could be used as an additional tool to monitor changes, providing additional information on segmental strength. PMID:22974002

  7. A practical approach to remote longitudinal follow-up of Parkinson's disease: the FOUND study.

    PubMed

    Tanner, Caroline M; Meng, Cheryl C; Ravina, Bernard; Lang, Anthony; Kurlan, Roger; Marek, Kenneth; Oakes, David; Seibyl, John; Flagg, Emily; Gauger, Lisa; Guest, Dolores D; Goetz, Christopher G; Kieburtz, Karl; DiEuliis, Diane; Fahn, Stanley; Elliott, Robin A; Shoulson, Ira

    2014-05-01

    The objective of this study was to examine a remote method for maintaining long-term contact with Parkinson's disease (PD) patients participating in clinical studies. Long-term follow-up of PD patients is needed to fill critical information gaps on progression, biomarkers, and treatment. Prospective in-person assessment can be costly and may be impossible for some patients. Remote assessment using mail and telephone contact may be a practical follow-up method. Patients enrolled in the multi-center Longitudinal and Biomarker Study in Parkinson's Disease (LABS-PD) in-person follow-up study in 2006 were invited to enroll in Follow-up of Persons With Neurologic Diseases (FOUND), which is overseen by a single center under a separate, central institutional review board protocol. FOUND uses mailed questionnaires and telephone interviews to assess PD status. FOUND follow-up continued when LABS-PD in-person visits ended in 2011. Retention and agreement between remote and in-person assessments were determined. In total, 422 of 499 (84.5%) of eligible patients volunteered, AND 96% of participants were retained. Of 60 patients who withdrew consent from LABS-PD, 51 were retained in FOUND. Of 341 patients who were active in LABS-PD, 340 were retained in FOUND (99.7%) when the in-person visits ceased. Exact agreement between remote and in-person assessments was ≥ 80% for diagnosis, disease features (eg, dyskinesias), and PD medication. Correlation between expert-rated and self-reported Unified Parkinson's Disease Rating Scale and Movement Disorder Society Unified Parkinson's Disease Rating Scale, which were examined at times separated by several months, was moderate or substantial for most items. Retention was excellent using remote follow-up of research participants with PD, providing a safety net when combined with in-person visits, and also is effective as a stand-alone assessment method, providing a useful alternative when in-person evaluation is not feasible. © 2014

  8. Executive function in early childhood: longitudinal measurement invariance and developmental change.

    PubMed

    Willoughby, Michael T; Wirth, R J; Blair, Clancy B

    2012-06-01

    This study tested the longitudinal measurement invariance and developmental changes of a newly developed battery of executive function (EF) tasks for use in early childhood. The battery was administered in the Family Life Project-a prospective longitudinal study (N = 1,292) of families who were oversampled from low-income and African American families at the birth of a new child-at assessments conducted when the child was 3, 4, and 5 years old. All 6 individual EF tasks exhibited strong measurement invariance over time. The EF battery, which was derived from the 6 individual tasks, exhibited partial strong invariance over time. Second-order latent growth curve models revealed individual differences in the levels but not rates of change in latent EF ability. The functional form of change was nonlinear; 60% of the total change in EF ability that was observed between the 3- and 5-year assessments occurred between the Year 3 and Year 4 assessments. Results are discussed with respect to the importance of establishing scalable measures of EF ability prior to investigating experiences that predict or are predicted by changes in EF during early childhood.

  9. Longitudinal and transversal bioimpedance measurements in addition to diagnosis of heart failure

    NASA Astrophysics Data System (ADS)

    Ribas, N.; Nescolarde, L.; Domingo, M.; Gastelurrutia, P.; Bayés-Genis, A.; Rosell-Ferrer, J.

    2010-04-01

    Heart Failure (HF) is a clinical syndrome characterised by signs of systemic and pulmonary fluid retention, shortness of breath and/or fatigue. There is a lack of reliable indicators of disease state. Benefits and applicability of non-invasive bioimpedance measurement in the hydration state of soft tissues have been validated, fundamentally, in dialysis patients. Four impedance configurations (2 longitudinal and 2 transversal) were analyzed in 48 HF patients (M=28, F=20) classified according to a clinical disease severity score (CDSS) derived from the Framingham criteria: CDSS<=2 (G1: M = 23, F = 14) and CDSS>2 (G2: M = 5, F = 6). The aim of this study is to analyze longitudinal and transversal bioimpedance measurement at 50 kHz, in addition to clinical diagnosis parameters of heart failure, including: clinical disease severity score (CDSS) and a biomarker concentrations (NT-proBNP). The Kolmogorov-Smirnov test was used for the normality test of all variables. The CDSS, NTproBNP and impedance parameters between groups (G1 and G2) were compared by mean of Mann Withney U-test. The statistical significance was considered with P < 0.05. Whole-body impedance measured was analyzed using RXc graph.

  10. Universal ultrasonic goniometer for Rayleigh and surface skimming longitudinal wave dispersion measurements

    NASA Astrophysics Data System (ADS)

    Barth, M.; Küttner, M.; Köhler, B.; Bamberg, J.; Baron, H.-U.

    2012-05-01

    There are several approaches for determining the Rayleigh wave dispersion of surface treated materials. Most of them are based either on ultrasonic probes in contact technique or on laser excitation or detection of ultrasound. Disadvantages of these methods for in-service use are coupling problems (contact methods) and very high device costs (laser based methods). The paper presents an immersion technique trying to avoid the disadvantages of the previous approaches for practical use. The High precision Ultrasound Goniometer (HUGO) allows to vary both: the sound beam angles and the distance between the excitation and detection sound beams. Thus, the Rayleigh wave velocity and its dispersion can be determined by two independent methods: by the drop in the reflexion coefficient at the Rayleigh angle and by change in travel time for a given change in travel distance. The dispersion can also be determined for surface skimming longitudinal waves. The application for stress determination in surface treated aero-engine materials is discussed.

  11. Repeatability and Minimal Detectable Change in Longitudinal Median Nerve Excursion Measures During Upper Limb Neurodynamic Techniques in a Mixed Population: A Pilot Study Using Musculoskeletal Ultrasound Imaging.

    PubMed

    Paquette, Philippe; Lamontagne, Martin; Higgins, Johanne; Gagnon, Dany H

    2015-07-01

    This study determined test-retest reliability and minimum detectable change in longitudinal median nerve excursion during upper limb neurodynamic tests (ULNTs). Seven participants with unilateral or bilateral carpal tunnel syndrome and 11 healthy participants were randomly tested with two ULNTs (i.e., tensioner and slider). Each ULNT was performed three times each at 45° and 90° of shoulder abduction on two separate visits. Video sequences of median nerve excursion, recorded by a physical therapist using ultrasound imaging, were quantified using computer software. The generalizability theory, encompassing a G-Study and a D-study, measured the dependability coefficient (Φ) along with standard error of measurement (SEM) accuracy and allowed various testing protocols to be proposed. The highest reliability (Φ = 0.84) and lowest minimal measurement error (SEM = 0.58 mm) of the longitudinal median nerve excursion were reached during the ULNT-slider performed with 45° of shoulder abduction and when measures obtained from three different image sequences recorded during a single visit were averaged. It is recommended that longitudinal median nerve excursion measures computed from three separate image sequences recorded during a single visit be averaged in clinical practice. Ideally, adding a second visit (six image sequences) is also suggested in research protocols. Copyright © 2015 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  12. Longitudinal Growth on Curriculum-Based Measurements Mathematics Measures for Early Elementary Students

    ERIC Educational Resources Information Center

    Lembke, Erica; Lee, Young Sun; Park, Yoon Soo; Hampton, David

    2016-01-01

    This article describes a study addressing how Curriculum-Based Measurement mathematics measures function as screening tools for students in grades Kindergarten through 2 over time, and for students in different demographic groups. Specifically, the research questions were: (1) What growth rates are produced for Curriculum-Based Measurement early…

  13. Longitudinal leak point pressure measurements in rats using a modified port à cath system.

    PubMed

    van Asselt, Els; van Mastrigt, Ron

    2013-12-01

    Stress urinary incontinence, defined as involuntary loss of urine secondary to an increase in abdominal pressure, represents one of the most significant urological problems. Several animal models to simulate stress urinary incontinence have been presented, including methods to quantify leak point pressure. We have modified an existing leak point pressure procedure to longitudinally quantify stress urinary incontinence in rats by introducing the port à cath system. Reproducible leak point pressure measurements were carried out over a period of more than 40 days at different bladder volumes. Leak point pressure neither showed a significant relationship with the number of times anesthesia was applied nor a significant change over time. The port à cath system provided a reliable, sensitive device for longitudinal urinary bladder pressure measurements in animals with an implanted bladder catheter. This set-up therefore enables the evaluation of bladder pressure in different models for stress urinary incontinence, such as vaginal distention or pudendal transection over long periods of time within the same animal. © 2013 The Japanese Urological Association.

  14. Minimizing Respondent Attrition in Longitudinal Research: Practical Implications from a Cohort Study of Adolescent Drinking.

    ERIC Educational Resources Information Center

    Boys, Annabel; Marsden, John; Stillwell, Garry; Hatchings, Kevin; Griffiths, Paul; Farrell, Michael

    2003-01-01

    Discusses the methods used to maximize retention in a longitudinal study of adolescent drinking. Strategies to minimize attrition included the collection of detailed contact information, incentives for participation, postcard and telephone reminders and telephone interviews. Ninety-six percent of the original sample completed the first follow-up…

  15. Minimizing Respondent Attrition in Longitudinal Research: Practical Implications from a Cohort Study of Adolescent Drinking.

    ERIC Educational Resources Information Center

    Boys, Annabel; Marsden, John; Stillwell, Garry; Hatchings, Kevin; Griffiths, Paul; Farrell, Michael

    2003-01-01

    Discusses the methods used to maximize retention in a longitudinal study of adolescent drinking. Strategies to minimize attrition included the collection of detailed contact information, incentives for participation, postcard and telephone reminders and telephone interviews. Ninety-six percent of the original sample completed the first follow-up…

  16. Linking Perceived Discrimination to Longitudinal Changes in African American Mothers' Parenting Practices

    ERIC Educational Resources Information Center

    Brody, Gene H.; Chen, Yi-Fu; Kogan, Steven M.; Murry, Velma McBride; Logan, Patricia; Luo, Zupei

    2008-01-01

    This longitudinal study was designed to test hypotheses, derived from a stress proliferation framework, regarding the association between perceived racial discrimination and changes in parenting among African American mothers in the rural South. A sample of 139 mothers and their children were interviewed 3 times at 1-year intervals. Mothers…

  17. Humor as an Instructional Practice: A Longitudinal Content Analysis of Humor Use in the Classroom.

    ERIC Educational Resources Information Center

    Dickmeyer, Scott G.

    A study analyzed the strengths and weaknesses of the use of humor in the classroom. A longitudinal content analysis of presentational and classroom studies from 1941 to 1991 was conducted. Earlier studies were included if they had been cited five or more times within articles on humor in the classroom. Scholars have argued that humor: is a…

  18. Methods and Measures: Growth Mixture Modeling--A Method for Identifying Differences in Longitudinal Change among Unobserved Groups

    ERIC Educational Resources Information Center

    Ram, Nilam; Grimm, Kevin J.

    2009-01-01

    Growth mixture modeling (GMM) is a method for identifying multiple unobserved sub-populations, describing longitudinal change within each unobserved sub-population, and examining differences in change among unobserved sub-populations. We provide a practical primer that may be useful for researchers beginning to incorporate GMM analysis into their…

  19. Anthropometric measurements and dental caries in children: a systematic review of longitudinal studies.

    PubMed

    Li, Ling-Wei; Wong, Hai Ming; Peng, Si-Min; McGrath, Colman P

    2015-01-01

    There is growing interest in the association between anthropometric measurements and dental caries in childhood over time (life-course studies). The aim of this review was to identify and systematically review the evidence of the association between anthropometric measurements and dental caries in childhood over time. PubMed, Institute for Scientific Information (ISI) Web of Knowledge, the Cochrane Library, and 6 other databases were searched to identify effective articles. A systematic approach involving critical appraisal was conducted to examine the relation between anthropometric measurements and dental caries in preschool- and school-aged populations from longitudinal studies. An initial search identified 1338 studies, with 59 potentially effective studies (κ = 0.82) and 17 effective studies (κ = 0.88). The quality of reporting among the studies ranged from 19.5 to 30.0 according to the Strengthening the Reporting of Observational studies in Epidemiology (STROBE) criteria. Among the effective studies, 2 studies in which caries was used to predict anthropometric measurements consistently found an inverse association and 15 studies in which anthropometric measurements were used to predict caries were inconsistent, with results appearing to be influenced by nonuniformity of assessments, setting, and procedure of measurements; age and ethnicity of participants; and confounders of dental caries. In conclusion, among >1000 studies identified, 17 informed this systematic review. The quality of reporting of these studies varied considerably. Evidence of the association between anthropometric measurements and dental caries is conflicting and remains inconclusive. © 2015 American Society for Nutrition.

  20. Anthropometric Measurements and Dental Caries in Children: A Systematic Review of Longitudinal Studies123

    PubMed Central

    Li, Ling-Wei; Wong, Hai Ming; Peng, Si-Min; McGrath, Colman P

    2015-01-01

    There is growing interest in the association between anthropometric measurements and dental caries in childhood over time (life-course studies). The aim of this review was to identify and systematically review the evidence of the association between anthropometric measurements and dental caries in childhood over time. PubMed, Institute for Scientific Information (ISI) Web of Knowledge, the Cochrane Library, and 6 other databases were searched to identify effective articles. A systematic approach involving critical appraisal was conducted to examine the relation between anthropometric measurements and dental caries in preschool- and school-aged populations from longitudinal studies. An initial search identified 1338 studies, with 59 potentially effective studies (κ = 0.82) and 17 effective studies (κ = 0.88). The quality of reporting among the studies ranged from 19.5 to 30.0 according to the Strengthening the Reporting of Observational studies in Epidemiology (STROBE) criteria. Among the effective studies, 2 studies in which caries was used to predict anthropometric measurements consistently found an inverse association and 15 studies in which anthropometric measurements were used to predict caries were inconsistent, with results appearing to be influenced by nonuniformity of assessments, setting, and procedure of measurements; age and ethnicity of participants; and confounders of dental caries. In conclusion, among >1000 studies identified, 17 informed this systematic review. The quality of reporting of these studies varied considerably. Evidence of the association between anthropometric measurements and dental caries is conflicting and remains inconclusive. PMID:25593143

  1. Reliability of neuroanatomical measurements in a multisite longitudinal study of youth at risk for psychosis.

    PubMed

    Cannon, Tyrone D; Sun, Frank; McEwen, Sarah Jacobson; Papademetris, Xenophon; He, George; van Erp, Theo G M; Jacobson, Aron; Bearden, Carrie E; Walker, Elaine; Hu, Xiaoping; Zhou, Lei; Seidman, Larry J; Thermenos, Heidi W; Cornblatt, Barbara; Olvet, Doreen M; Perkins, Diana; Belger, Aysenil; Cadenhead, Kristin; Tsuang, Ming; Mirzakhanian, Heline; Addington, Jean; Frayne, Richard; Woods, Scott W; McGlashan, Thomas H; Constable, R Todd; Qiu, Maolin; Mathalon, Daniel H; Thompson, Paul; Toga, Arthur W

    2014-05-01

    Multisite longitudinal neuroimaging designs are used to identify differential brain structural change associated with onset or progression of disease. The reliability of neuroanatomical measurements over time and across sites is a crucial aspect of power in such studies. Prior work has found that while within-site reliabilities of neuroanatomical measurements are excellent, between-site reliability is generally more modest. Factors that may increase between-site reliability include standardization of scanner platform and sequence parameters and correction for between-scanner variations in gradient nonlinearities. Factors that may improve both between- and within-site reliability include use of registration algorithms that account for individual differences in cortical patterning and shape. In this study 8 healthy volunteers were scanned twice on successive days at 8 sites participating in the North American Prodrome Longitudinal Study (NAPLS). All sites employed 3 Tesla scanners and standardized acquisition parameters. Site accounted for 2 to 30% of the total variance in neuroanatomical measurements. However, site-related variations were trivial (<1%) among sites using the same scanner model and 12-channel coil or when correcting for between-scanner differences in gradient nonlinearity and scaling. Adjusting for individual differences in sulcal-gyral geometries yielded measurements with greater reliabilities than those obtained using an automated approach. Neuroimaging can be performed across multiple sites at the same level of reliability as at a single site, achieving within- and between-site reliabilities of 0.95 or greater for gray matter density in the majority of voxels in the prefrontal and temporal cortical surfaces as well as for the volumes of most subcortical structures.

  2. Longitudinal association of anthropometric measures of adiposity with cardiometabolic risk factors in postmenopausal women

    PubMed Central

    Kabat, Geoffrey C.; Heo, Moonseong; Van Horn, Linda V.; Kazlauskaite, Rasa; Getaneh, Asqual; Ard, Jamy; Vitolins, Mara Z.; Waring, Molly E.; Zaslavsky, Oleg; Smoller, Sylvia Wassertheil; Rohan, Thomas E.

    2015-01-01

    Purpose Some studies suggest that anthropometric measures of abdominal obesity may be superior to body mass index for the prediction of cardiometabolic risk factors; however, most studies have been cross-sectional. Our aim was to prospectively examine the association of change in body mass index (BMI), waist-hip ratio (WHR), waist circumference (WC), and waist circumference-height ratio (WCHtR) with change in markers of cardiometabolic risk in a population of postmenopausal women. Methods We used a subsample of participants in the Women’s Health Initiative aged 50 to 79 at entry with available fasting blood samples and anthropometric measurements obtained at multiple time points over 12.8 years of follow-up (N = 2,672). The blood samples were used to measure blood glucose, insulin, total cholesterol, LDL-C, HDL-C, and triglycerides at baseline, and at years 1, 3, and 6. We conducted mixed-effects linear regression analyses to examine associations at baseline and longitudinal associations between change in anthropometric measures and change in cardiometabolic risk factors, adjusting for covariates. Results In longitudinal analyses, change in BMI, WC, and WCHtR robustly predicted change in cardiometabolic risk, whereas change in WHR did not. The strongest associations were seen for change in triglycerides, glucose, and HDL-C (inverse association). Conclusion Increase in BMI, WC, and WCHtR strongly predicted increases in serum triglycerides and glucose, and reduced HDL-C. WC and WCHtR were superior to BMI in predicting serum glucose, HDL-C, and triglycerides. WCHtR was superior to WC only in predicting serum glucose. BMI, WC, and WCHtR were all superior to WHR. PMID:25453348

  3. Epidemiologic Methods of Assessing Asthma and Wheezing Episodes in Longitudinal Studies: Measures of Change and Stability

    PubMed Central

    Soto-Ramírez, Nelís; Ziyab, Ali H.; Karmaus, Wilfried; Zhang, Hongmei; Kurukulaaratchy, Ramesh J.; Ewart, Susan; Arshad, Syed Hasan

    2013-01-01

    Background In settings in which diseases wax and wane, there is a need to measure disease dynamics in longitudinal studies. Traditional measures of disease occurrence (eg, cumulative incidence) do not address change or stability or are limited to stable cohorts (eg, incidence) and may thus lead to erroneous conclusions. To illustrate how different measures can be used to detect disease dynamics, we investigated sex differences in the occurrence of asthma and wheezing, using a population-based study cohort that covered the first 18 years of life. Methods In the Isle of Wight birth cohort (n = 1456), prevalence, incidence, cumulative incidence, positive and negative transitions, and remission were determined at ages 1 or 2, 4, 10, and 18 years. Latent transition analysis was used to simultaneously identify classes of asthma and wheezing (related phenotypes) and characterize transition probabilities over time. Trajectory analysis was used to characterize the natural history of asthma and wheezing. Results Regarding time-specific changes, positive and negative transition probabilities were more informative than other measures of associations because they revealed a sex switchover in asthma prevalence (P < 0.05). Transition probabilities were able to identify the origin of a sex-specific dynamic; in particular, prior wheezing transitioned to asthma at age 18 years among girls but not among boys. In comparison with latent transition analysis, trajectory analysis did not directly identify a switchover in prevalence among boys and girls. Conclusions In longitudinal analyses, transition analyses that impose minimal restrictions on data are needed in order to produce appropriate information on disease dynamics. PMID:23994864

  4. Measuring learning by trainees in general practice

    PubMed Central

    Howie, J. G. R.; Dingwall-Fordyce, Ianthe

    1976-01-01

    Twenty simulated consultations with patients having a respiratory illness were carried out by 20 trainees at the start and finish of a training year in general practice, using the same method as used in a previous study of principals in general practice. During the course of the year, the trainees as a group closely approached the behaviour—in the defined terms of the study—of principals as a group. The trend was more marked for doctors on a three-year training programme than for those on a one-year programme. In 11 cases direct comparison between trainee and trainer was possible. It was difficult to identify changes in behaviour as being due to either group influences or individual trainer influences, but it appeared that atypical trainers do not necessarily produce atypical trainees and typical trainers do not prevent the development of individuality in trainees. The technique of simulated consultation may assist the difficult task of evaluating training for general practice. PMID:957308

  5. Understanding and Measuring Parent Use of Food to Soothe Infant and Toddler Distress: A Longitudinal Study from 6 to 18 months of age

    PubMed Central

    Stifter, Cynthia A.; Moding, Kameron J.

    2015-01-01

    The present study examined the development of parent use of food to soothe infant distress by examining this feeding practice longitudinally when infants were 6, 12 and 18 months of age. Two measures of feeding to soothe were obtained: parent self-report and observations of food to soothe during each laboratory visit. Demographic and maternal predictors of food to soothe were examined as well as the outcome, infant weight gain. The findings showed that the two measures of food to soothe were unrelated but did reveal similar and unique relations with predictor variables such as parent feeding style and maternal self-efficacy. Only observations of the use of food to soothe were related to infant weight gain. The findings indicate that the two measures of food to soothe may be complementary and that observations of this feeding practice may capture certain relations that are not obtained through the use of self-report. PMID:26164121

  6. Understanding and measuring parent use of food to soothe infant and toddler distress: A longitudinal study from 6 to 18 months of age.

    PubMed

    Stifter, Cynthia A; Moding, Kameron J

    2015-12-01

    The present study examined the development of parent use of food to soothe infant distress by examining this feeding practice longitudinally when infants were 6, 12 and 18 months of age. Two measures of feeding to soothe were obtained: parent self-report and observations of food to soothe during each laboratory visit. Demographic and maternal predictors of food to soothe were examined as well as the outcome, infant weight gain. The findings showed that the two measures of food to soothe were unrelated but did reveal similar and unique relations with predictor variables such as parent feeding style and maternal self-efficacy. Only observations of the use of food to soothe were related to infant weight gain. The findings indicate that the two measures of food to soothe may be complementary and that observations of this feeding practice may capture certain relations that are not obtained through the use of self-report. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Measuring Changes in the Economics of Medical Practice.

    PubMed

    Fleming, Christopher; Rich, Eugene; DesRoches, Catherine; Reschovsky, James; Kogan, Rachel

    2015-08-01

    For the latter third of the twentieth century, researchers have estimated production and cost functions for physician practices. Today, those attempting to measure the inputs and outputs of physician practice must account for many recent changes in models of care delivery. In this paper, we review practice inputs and outputs as typically described in research on the economics of medical practice, and consider the implications of the changing organization of medical practice and nature of physician work. This evolving environment has created conceptual challenges in what are the appropriate measures of output from physician work, as well as what inputs should be measured. Likewise, the increasing complexity of physician practice organizations has introduced challenges to finding the appropriate data sources for measuring these constructs. Both these conceptual and data challenges pose measurement issues that must be overcome to study the economics of modern medical practice. Despite these challenges, there are several promising initiatives involving data sharing at the organizational level that could provide a starting point for developing the needed new data sources and metrics for physician inputs and outputs. However, additional efforts will be required to establish data collection approaches and measurements applicable to smaller and single specialty practices. Overcoming these measurement and data challenges will be key to supporting policy-relevant research on the changing economics of medical practice.

  8. A Longitudinal Study of Teaching Practice and Early Career Decisions: A Cautionary Tale

    ERIC Educational Resources Information Center

    Cochran-Smith, Marilyn; McQuillan, Patrick; Mitchell, Kara; Terrell, Dianna Gahlsdorf; Barnatt, Joan; D'Souza, Lisa; Jong, Cindy; Shakman, Karen; Lam, Karen; Gleeson, Ann Marie

    2012-01-01

    Although the turnover rate among beginning teachers has been a major concern for some time, most studies do not link teacher retention with teaching practice. In contrast, this study looks specifically at career decisions coupled with practice. Guided by a view of teaching as social and cultural practice, the study used multiple qualitative data…

  9. Measuring Service Quality: From Theory into Practice.

    ERIC Educational Resources Information Center

    Calvert, Philip J.

    1997-01-01

    Academic library managers need a multimethod, objective, valid tool for measuring service quality. Examines three research studies in the measurement of service quality in Australian and New Zealand academic libraries: the Hernon and Altman Study; Hernon and Calvert Study; and the University of Waikato (Hamilton, New Zealand) Survey, a two-stage…

  10. 38 CFR 21.7674 - Measurement of practical training courses.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... on the basis of credit hours or clock hours of attendance, whichever is appropriate. The clock hours..., practical trained nurse, or licensed practical nurse will be measured on credit hours or clock hours of... of § 21.7720(b)(9) will be measured on a clock-hour basis as provided in § 21.7672. However,...

  11. 38 CFR 21.7674 - Measurement of practical training courses.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... on the basis of credit hours or clock hours of attendance, whichever is appropriate. The clock hours..., practical trained nurse, or licensed practical nurse will be measured on credit hours or clock hours of... of § 21.7720(b)(9) will be measured on a clock-hour basis as provided in § 21.7672. However,...

  12. 38 CFR 21.7674 - Measurement of practical training courses.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... on the basis of credit hours or clock hours of attendance, whichever is appropriate. The clock hours..., practical trained nurse, or licensed practical nurse will be measured on credit hours or clock hours of... of § 21.7720(b)(9) will be measured on a clock-hour basis as provided in § 21.7672. However,...

  13. Predicting the long-term sustainability of evidence-based practices in mental health care: an 8-year longitudinal analysis.

    PubMed

    Peterson, Alison E; Bond, Gary R; Drake, Robert E; McHugo, Gregory J; Jones, Amanda M; Williams, Jessica R

    2014-07-01

    Few studies have examined predictors of long-term sustainability of evidence-based practices in mental health. This study used assessments of five evidence-based practices implemented in 49 sites in eight states at baseline and years 2, 4, and 8. Program characteristics, implementation characteristics, reinforcement activities, and sustainability factors were used to predict program survival status. The majority of predictors were not significant. Supervisor turnover in year 4 predicted survival status in year 8, but site characteristics, fidelity at implementation, quality improvement activities, and post-implementation activities had little impact on long-term program survival. This study extends previous sustainability research by examining the long-term impact of internal program factors over a substantial period of time using longitudinal prediction. Future research should also consider the influence of external factors such as financial policies.

  14. Practical application of in situ aerosol measurement

    SciTech Connect

    O`Hern, T.J.; Rader, D.J.

    1993-09-01

    The use of in situ, real-time measurement techniques permits the characterization of airborne droplets and particles under conditions where traditional sampling methods can fail. For example, sampling method rely on the ability to sample and transport particles without biasing the properties of interest, and often are not applicable in harsh environment. Although in situ methods offer unique opportunities in these cases, these techniques introduce new concerns and must be used carefully if accurate measurement are to be made. Several in situ measurement techniques are reviewed here. As the field is rapidly evolving, the discussion is limited to those techniques which: (1) are commercially available, (2) provide real-time output, (3) measure the aerosol size distribution. Discussion is divided between single particle counters (which provide a flux-based or temporal measurement) and ensemble techniques (which provide a concentration-based or spatial measurement). Specific techniques discussed include phase Doppler, Mie scattering, and Fraunhofer diffraction, and commercial instruments based on these techniques.

  15. Family-Based Association Tests with longitudinal measurements: handling missing data.

    PubMed

    Ding, Xiao; Laird, Nan

    2009-01-01

    Several family-based approaches have been previously proposed to enhance the power for testing genetic association when the traits are measured longitudinally or repeatedly. In this paper, we show that some of these FBAT approaches can be easily extended to accommodate incomplete data and remain unbiased tests. We also show that because of the nature of FBAT approaches, we can impute the missing phenotypes without biasing our tests and achieve higher power. We propose two imputation techniques based on E-M algorithm and the conditional mean model, respectively. Through simulation studies, these two imputation techniques are shown to have correct false positive rate and generally achieve higher power than complete case analysis or simple mean-imputation. Application of these approaches for testing an association between Body Mass Index and a previously reported candidate SNP confirms our results.

  16. On the measurement of the proton-air cross section using longitudinal shower profiles

    NASA Astrophysics Data System (ADS)

    Ulrich, R.; Blümer, J.; Engel, R.; Schüssler, F.; Unger, M.

    2008-01-01

    In this paper, we will discuss the prospects of deducing the proton-air cross section from fluorescence telescope measurements of extensive air showers. As it is not possible to observe the point of first interaction, X1, directly, other observables closely linked to X1 must be inferred from the longitudinal profiles. This introduces a dependence on the models used to describe the shower development. The most straightforward candidate for a good correlation to X1 is the depth of shower maximum Xmax. We will discuss the sensitivity of an Xmax-based analysis on σ and quantify the systematic uncertainties arising from the model dependence, parameters of the reconstruction method itself and a possible non-proton contamination of the selected shower sample.

  17. Family-Based Association Tests with Longitudinal Measurements: Handling Missing Data

    PubMed Central

    Ding, Xiao; Laird, Nan

    2009-01-01

    Several family-based approaches have been previously proposed to enhance the power for testing genetic association when the traits are measured longitudinally or repeatedly. In this paper, we show that some of these FBAT approaches can be easily extended to accommodate incomplete data and remain unbiased tests. We also show that because of the nature of FBAT approaches, we can impute the missing phenotypes without biasing our tests and achieve higher power. We propose two imputation techniques based on E-M algorithm and the conditional mean model, respectively. Through simulation studies, these two imputation techniques are shown to have correct false positive rate and generally achieve higher power than complete case analysis or simple mean-imputation. Application of these approaches for testing an association between Body Mass Index and a previously reported candidate SNP confirms our results. PMID:19365136

  18. Measurement and relevance of personality characteristics in persons with dementia: a longitudinal perspective.

    PubMed

    Twigg, Prudence; Burgener, Sandy C; Popovich, Ann

    2007-01-01

    Studies of personality and outcomes in persons with dementia (PWD) have focused primarily on disease stages or change from premorbid personality following diagnosis. Data from a longitudinal study of 96 caregiver/PWD dyads was used to evaluate psychometric properties of two personality measures: one rated by proxies, the other by PWD. Proxy ratings indicate change in strength of personality traits across disease stages; self-ratings were stable, excepting decreased extroversion. Items detracting from reliability of some subscales reflected disease-related changes in PWD rather than true shifts in personality. Findings support importance of collecting both proxy and self-ratings of personality, examining individual items contributing to low reliability, and evaluating change in personality within the context of expected changes inherent in dementia.

  19. A Longitudinal Analysis of Adolescent Smoking: Using Smoking Status to Differentiate the Influence of Body Weight Measures

    ERIC Educational Resources Information Center

    Hong, Traci; Johnson, Carolyn

    2013-01-01

    Background: Previous research has reported mixed results on the association between body weight measures (ie, perception of weight and weight loss goal) and cigarette smoking prevalence--and how these associations vary by sex and race. This longitudinal study assessed the relationship between these 2 body weight measures and smoking prevalence by…

  20. A Longitudinal Analysis of Adolescent Smoking: Using Smoking Status to Differentiate the Influence of Body Weight Measures

    ERIC Educational Resources Information Center

    Hong, Traci; Johnson, Carolyn

    2013-01-01

    Background: Previous research has reported mixed results on the association between body weight measures (ie, perception of weight and weight loss goal) and cigarette smoking prevalence--and how these associations vary by sex and race. This longitudinal study assessed the relationship between these 2 body weight measures and smoking prevalence by…

  1. Modeling Life-Span Growth Curves of Cognition Using Longitudinal Data with Multiple Samples and Changing Scales of Measurement

    ERIC Educational Resources Information Center

    McArdle, John J.; Grimm, Kevin J.; Hamagami, Fumiaki; Bowles, Ryan P.; Meredith, William

    2009-01-01

    The authors use multiple-sample longitudinal data from different test batteries to examine propositions about changes in constructs over the life span. The data come from 3 classic studies on intellectual abilities in which, in combination, 441 persons were repeatedly measured as many as 16 times over 70 years. They measured cognitive constructs…

  2. Causal Inference in Longitudinal Comparative Effectiveness Studies With Repeated Measures of A Continuous Intermediate Variable

    PubMed Central

    Wang, Chen-Pin; Jo, Booil; Brown, C. Hendricks

    2014-01-01

    We propose a principal stratification approach to assess causal effects in non-randomized longitudinal comparative effectiveness studies with a binary endpoint outcome and repeated measures of a continuous intermediate variable. Our method is an extension of the principal stratification approach by Lin et al. [10,11], originally proposed for a longitudinal randomized study to assess the treatment effect of a continuous outcome adjusting for the heterogeneity of a repeatedly measured binary intermediate variable. Our motivation for this work comes from a comparison of the effect of two glucose-lowering medications on a clinical cohort of patients with type 2 diabetes. Here we consider a causal inference problem assessing how well the two medications work relative to one another on two binary endpoint outcomes: cardiovascular disease related hospitalization and all-cause mortality. Clinically, these glucose-lowering medications can have differential effects on the intermediate outcome, glucose level over time. Ultimately we want to compare medication effects on the endpoint outcomes among individuals in the same glucose trajectory stratum while accounting for the heterogeneity in baseline covariates (i.e., to obtain “principal effects” on the endpoint outcomes). The proposed method involves a 3-step model estimation procedure. Step 1 identifies principal strata associated with the intermediate variable using hybrid growth mixture modeling analyses [13]. Step 2 obtains the stratum membership using the pseudoclass technique [17,18], and derives propensity scores for treatment assignment. Step 3 obtains the stratum-specific treatment effect on the endpoint outcome weighted by inverse propensity probabilities derived from Step 2. PMID:24577715

  3. Causal inference in longitudinal comparative effectiveness studies with repeated measures of a continuous intermediate variable.

    PubMed

    Wang, Chen-Pin; Jo, Booil; Brown, C Hendricks

    2014-09-10

    We propose a principal stratification approach to assess causal effects in nonrandomized longitudinal comparative effectiveness studies with a binary endpoint outcome and repeated measures of a continuous intermediate variable. Our method is an extension of the principal stratification approach originally proposed for the longitudinal randomized study "Prevention of Suicide in Primary Care Elderly: Collaborative Trial" to assess the treatment effect on the continuous Hamilton depression score adjusting for the heterogeneity of repeatedly measured binary compliance status. Our motivation for this work comes from a comparison of the effect of two glucose-lowering medications on a clinical cohort of patients with type 2 diabetes. Here, we consider a causal inference problem assessing how well the two medications work relative to one another on two binary endpoint outcomes: cardiovascular disease-related hospitalization and all-cause mortality. Clinically, these glucose-lowering medications can have differential effects on the intermediate outcome, glucose level over time. Ultimately, we want to compare medication effects on the endpoint outcomes among individuals in the same glucose trajectory stratum while accounting for the heterogeneity in baseline covariates (i.e., to obtain 'principal effects' on the endpoint outcomes). The proposed method involves a three-step model estimation procedure. Step 1 identifies principal strata associated with the intermediate variable using hybrid growth mixture modeling analyses. Step 2 obtains the stratum membership using the pseudoclass technique and derives propensity scores for treatment assignment. Step 3 obtains the stratum-specific treatment effect on the endpoint outcome weighted by inverse propensity probabilities derived from Step 2. Copyright © 2014 John Wiley & Sons, Ltd.

  4. [Body temperature measurement in daily practice].

    PubMed

    Sermet-Gaudelus, I; Chadelat, I; Lenoir, G

    2005-08-01

    The use of rectal mercury thermometer has long been the standard method for measurement of body temperature. The restriction of mercury use since 1996 has led to development of other devices. The liquid crystal strip thermometer held against the forehead has a low sensitivity. The single-use chemical thermometer measures oral temperature. Its accuracy must be evaluated. Infrared ear thermometers are routinely used because it is convenient and fast to use. However, numerous studies have shown that it does not show sufficient correlation with rectal temperature, leading to the risk to miss cases of true fever. Rectal temperature remains the gold standard in case of fever. Rectal temperature measurement with an electronic device is well correlated with the glass mercury standard. Galistan thermometer accuracy must be evaluated because of sterilization of the whole device, which is not the case for the electronic thermometer. A pediatric study is necessary to evaluate the performance of this device in comparison with the electronic thermometer.

  5. Heritability of calcaneal quantitative ultrasound measures in healthy adults from the Fels Longitudinal Study.

    PubMed

    Lee, Miryoung; Czerwinski, Stefan A; Choh, Audrey C; Towne, Bradford; Demerath, Ellen W; Chumlea, Wm Cameron; Sun, Shumei S; Siervogel, Roger M

    2004-11-01

    Quantitative ultrasound (QUS) measurements of bone have been reported to predict osteoporotic fracture risk in postmenopausal women and older men. Although many studies have examined the heritability of bone mineral density (BMD), few studies have estimated the heritability of calcaneal QUS phenotypes. In the present study, we examined the genetic regulation of calcaneal QUS parameters in individuals from nuclear and extended families. The study population includes 260 men and 295 women aged 18-91 years (mean+/-SD: 46+/-16 years) who belong to 111 pedigrees in the Fels Longitudinal Study. Three measures of calcaneal structure were collected from both the right and left heel using the Sahara bone sonometer. These measures included broadband ultrasound attenuation (BUA), speed of sound (SOS), and the quantitative ultrasound index (QUI). We used a variance components based maximum likelihood method to estimate the heritability of QUS parameters while simultaneously adjusting for covariate effects. Additionally, we used bivariate extensions of these methods to calculate additive genetic and random environmental correlations among QUS measures. All phenotypes demonstrated statistically significant heritabilities (P<0.0000001). Heritabilities in the right heel (h2+/-SE) were h2=0.59+/-0.10 for BUA, h2=0.73+/-0.09 for SOS, and h2=0.72+/-0.09 for QUI. Similarly, heritabilities for the left heel were h2=0.52+/-0.10, h2=0.75+/-0.10, and h2=0.70+/0.10, respectively. There was evidence for significant genetic and environmental correlations among these six QUS measures. Combinations of QUS measures in the right and left heel demonstrated genetic correlations of 0.94-0.99 and all were significantly different from one indicating at least a partially unique genetic architecture for each of these measures. This study demonstrates that QUS measures of the calcaneus among healthy men and women are heritable, and there are large shared additive genetic effects among all of the traits

  6. The 9-item Bergen Burnout Inventory: factorial validity across organizations and measurements of longitudinal data.

    PubMed

    Feldt, Taru; Rantanen, Johanna; Hyvönen, Katriina; Mäkikangas, Anne; Huhtala, Mari; Pihlajasaari, Pia; Kinnunen, Ulla

    2014-01-01

    The present study tested the factorial validity of the 9-item Bergen Burnout Inventory (BBI-9). The BBI-9 is comprised of three core dimensions: (1) exhaustion at work; (2) cynicism toward the meaning of work; and (3) sense of inadequacy at work. The study further investigated whether the three-factor structure of the BBI-9 remains the same across different organizations (group invariance) and measurement time points (time invariance). The factorial group invariance was tested using a cross-sectional design with data pertaining to managers (n=742), and employees working in a bank (n=162), an engineering office (n=236), a public sector organization divided into three service areas: administration (n=102), education and culture (n=581), and social affairs and health (n=1,505). Factorial time invariance was tested using longitudinal data pertaining to managers, with three measurements over a four-year follow-up period. The confirmatory factor analysis revealed that the three-factor structure of the BBI-9 was invariant across cross-sectional samples. The factorial invariance was also supported across measurement times. To conclude, the factorial structure of the BBI-9 was found to remain the same regardless of the sample properties and measurement times.

  7. The 9-item Bergen Burnout Inventory: Factorial Validity Across Organizations and Measurements of Longitudinal Data

    PubMed Central

    Feldt, Taru; RANTANEN, Johanna; HYVÖNEN, Katriina; MÄKIKANGAS, Anne; HUHTALA, Mari; PIHLAJASAARI, Pia; KINNUNEN, Ulla

    2013-01-01

    The present study tested the factorial validity of the 9-item Bergen Burnout Inventory (BBI-9)1). The BBI-9 is comprised of three core dimensions: (1) exhaustion at work; (2) cynicism toward the meaning of work; and (3) sense of inadequacy at work. The study further investigated whether the three-factor structure of the BBI-9 remains the same across different organizations (group invariance) and measurement time points (time invariance). The factorial group invariance was tested using a cross-sectional design with data pertaining to managers (n=742), and employees working in a bank (n=162), an engineering office (n=236), a public sector organization divided into three service areas: administration (n=102), education and culture (n=581), and social affairs and health (n=1,505). Factorial time invariance was tested using longitudinal data pertaining to managers, with three measurements over a four-year follow-up period. The confirmatory factor analysis revealed that the three-factor structure of the BBI-9 was invariant across cross-sectional samples. The factorial invariance was also supported across measurement times. To conclude, the factorial structure of the BBI-9 was found to remain the same regardless of the sample properties and measurement times. PMID:24366535

  8. Measuring Teacher Efficacy to Implement Inclusive Practices

    ERIC Educational Resources Information Center

    Sharma, Umesh; Loreman, Tim; Forlin, Chris

    2012-01-01

    The purpose of this study was to develop an instrument to measure perceived teacher efficacy to teach in inclusive classrooms. An 18-item scale was developed on a sample of 607 pre-service teachers selected from four countries (Canada, Australia, Hong Kong and India). Factor analysis of responses from the sample revealed three factors: efficacy in…

  9. Measuring Teacher Efficacy to Implement Inclusive Practices

    ERIC Educational Resources Information Center

    Sharma, Umesh; Loreman, Tim; Forlin, Chris

    2012-01-01

    The purpose of this study was to develop an instrument to measure perceived teacher efficacy to teach in inclusive classrooms. An 18-item scale was developed on a sample of 607 pre-service teachers selected from four countries (Canada, Australia, Hong Kong and India). Factor analysis of responses from the sample revealed three factors: efficacy in…

  10. Longitudinal emittance: An introduction to the concept and survey of measurement techniques including design of a wall current monitor

    SciTech Connect

    Webber, R.C.

    1990-03-01

    The properties of charged particle beams associated with the distribution of the particles in energy and in time can be grouped together under the category of longitudinal emittance. This article is intended to provide an intuitive introduction to the concepts longitudinal emittance; to provide an incomplete survey of methods used to measure this emittance and the related properties of bunch length and momentum spread; and to describe the detailed design of a 6 Ghz bandwidth resistive wall current monitor useful for measuring bunch shapes of moderate to high intensity beams. Overall, the article is intended to be broad in scope, in most cases deferring details to cited original papers. 37 refs., 21 figs.

  11. Measurement of Single and Double Spin Asymmetries in Deep Inelastic Pion Electroproduction with a Longitudinally Polarized Target

    SciTech Connect

    Avakian, H; Bosted, P; Elouadrhiri, L; Adhikari, K P; Aghasyan, M; Amaryan, M; Anghinolfi, M; Baghdasaryan, H; Ball, J; Battaglieri, M; Bedlinskiy, I; Biselli, A S; Branford, D; Briscoe, W J; Brooks, W; Carman, D S; Casey, L; Cole, P L; Collins, P; Crabb, D; Crede, V; D'Angelo, A; Daniel, A; Dashyan, N; DeVita, R; DeSanctis, E; Deur, A; Dey, B; Dhamija, S; Dickson, R; Djalali, C; Dodge, G; Doughty, D; Dupre, R; El Alaoui, A; Eugenio, P; Fegan, S; Fersch, M; Guler, N; Guo, L; Hafidi, K; Hakobyan, H; Hanretty, C; Hassall, N; Heddle, D; Hicks, K; Holtrop, M; Ilieva, Y; Ireland, D G; Isupov, E L; Jawalkar, S S; Jo, H S; Joo, K; Keller, D; Khandaker, M; Khetarpal,; Kim, W; Klein, A; Klein, F J; Konczykowski, P; Kubarovsky, V; Kuhn, S E; Kuleshov, S V; Kuznetsov, V; Livingston, K; Lu, H Y; Markov, N; Mayer, M; McAndrew, J; McCracken, M E; McKInnon, B; Meyer, C A; Mineeva, T; Mirazita, M; Mokeev, V; Moreno, B; Moriya, K; Morrison, B; Moutarde, H; Munevar, E; Nadel-Turonski, P; Nasseripour, R; Niccolai, S; Niculescu, G; Niculescu, I; Niroula, M R; Osipenko, M; Ostrovidov, A I; Paremuzyan, R; Park, K; Park, S; Pasyuk, E; Anefalos Pereira, S; Perrin, Y; Pisano, S; Pogorelko, O; Price, J W; Procureur, S; Prok, Protopopescu; Raue, B A; Ricco, G; Ripani, M; Rosner, G; Rossi, P; Sabatie, F; Saini, M S; Salamanca, J; Salgado, C; Schumacher, R A; Seder, E; Seraydaryan, H; Sharabian, Y G; Sober, D I; Sokhan, D; Stapanyan, S S; Stepanyan, S; Stoler, P; Strauch, S; Suleiman, R; Taiuti, M; Tedeschi, D J; Tkachenko, S; Ungaro, M; Vernarsky, B; Vineyard, M F; Voutier, E; Watts, D P; Weinstein, L B; Weygand, D P; Wood, M H; Zhang, J; Zhao, B; Zhao, Z W

    2010-12-01

    We report the first measurement of the transverse momentum dependence of double spin asymmetries in semi-inclusive production of pions in deep inelastic scattering off the longitudinally polarized proton. Data have been obtained using a polarized electron beam of 5.7 GeV with the CLAS detector at the Thomas Jefferson National Accelerator Facility (JLab). A significant non-zero $\\sin2\\phi$ single spin asymmetry was also observed for the first time indicating strong spin-orbit correlations for transversely polarized quarks in the longitudinally polarized proton. The azimuthal modulations of single spin asymmetries have been measured over a wide kinematic range.

  12. Participant retention practices in longitudinal clinical research studies with high retention rates.

    PubMed

    Abshire, Martha; Dinglas, Victor D; Cajita, Maan Isabella A; Eakin, Michelle N; Needham, Dale M; Himmelfarb, Cheryl Dennison

    2017-02-20

    There is a need for improving cohort retention in longitudinal studies. Our objective was to identify cohort retention strategies and implementation approaches used in studies with high retention rates. Longitudinal studies with ≥200 participants, ≥80% retention rates over ≥1 year of follow-up were queried from an Institutional Review Board database at a large research-intensive U.S. university; additional studies were identified through networking. Nineteen (86%) of 22 eligible studies agreed to participate. Through in-depth semi-structured interviews, participants provided retention strategies based on themes identified from previous literature reviews. Synthesis of data was completed by a multidisciplinary team. The most commonly used retention strategies were: study reminders, study visit characteristics, emphasizing study benefits, and contact/scheduling strategies. The research teams were well-functioning, organized, and persistent. Additionally, teams tailored their strategies to their participants, often adapting and innovating their approaches. These studies included specialized and persistent teams and utilized tailored strategies specific to their cohort and individual participants. Studies' written protocols and published manuscripts often did not reflect the varied strategies employed and adapted through the duration of study. Appropriate retention strategy use requires cultural sensitivity and more research is needed to identify how strategy use varies globally.

  13. [Good laboratory practice of equilibrium solubility measurement].

    PubMed

    Baka, Edit

    2011-01-01

    The biggest part of my PhD work was the standardization of the classical saturation shake-flask solubility method. During the experiments we examined systematically which parameters have significant influence on the solubility value and how large experimental error (standard deviation) is caused by them in the solubility method. Hydrochlorothiazide was used as model compound. Modification in temperature, sedimentation time, composition of aqueous buffer and the technique of separation of solid and liquid phases were found to influence the equilibrium solubility results strongly. However, variations in the amount of solid excess and stirring time were found to have less influence. Based on this standardization study, we developed a new shorter (36 hours) protocol for measurements of equilibrium solubility of drug molecules. The new protocol was validated with the aid of 6 structurally different compounds. The equilibrium solubility was measured by both (standard and new) protocols. The results were in good agreement, so the shorter protocol can be applied to measure the equilibrium solubility of drug compounds.

  14. CHI: A contemporaneous health index for degenerative disease monitoring using longitudinal measurements.

    PubMed

    Huang, Yijun; Meng, Qiang; Evans, Heather; Lober, William; Cheng, Yu; Qian, Xiaoning; Liu, Ji; Huang, Shuai

    2017-09-01

    In this paper, we develop a novel formulation for contemporaneous patient risk monitoring by exploiting the emerging data-rich environment in many healthcare applications, where an abundance of longitudinal data that reflect the degeneration of the health condition can be continuously collected. Our objective, and the developed formulation, is fundamentally different from many existing risk score models for different healthcare applications, which mostly focus on predicting the likelihood of a certain outcome at a pre-specified time. Rather, our formulation translates multivariate longitudinal measurements into a contemporaneous health index (CHI) that captures patient condition changes over the course of progression. Another significant feature of our formulation is that, CHI can be estimated with or without label information, different from other risk score models strictly based on supervised learning. To develop this formulation, we focus on the degenerative disease conditions, for which we could utilize the monotonic progression characteristic (either towards disease or recovery) to learn CHI. Such a domain knowledge leads us to a novel learning formulation, and on top of that, we further generalize this formulation with a capacity to incorporate label information if available. We further develop algorithms to mitigate the challenges associated with the nonsmooth convex optimization problem by first identifying its dual reformulation as a constrained smooth optimization problem, and then, using the block coordinate descent algorithm to iteratively solve the optimization with a derived efficient projection at each iteration. Extensive numerical studies are performed on both synthetic datasets and real-world applications on Alzheimer's disease and Surgical Site Infection, which demonstrate the utility and efficacy of the proposed method on degenerative conditions that include a wide range of applications. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Measurements of longitudinal gamma ray distribution using a multichannel fiber-optic Cerenkov radiation sensor

    NASA Astrophysics Data System (ADS)

    Shin, S. H.; Jeon, D.; Kim, J. S.; Jang, J. S.; Jang, K. W.; Yoo, W. J.; Moon, J. H.; Park, B. G.; Kim, S.; Lee, B.

    2014-11-01

    Cerenkov radiation occurs when charged particles are moving faster than the speed of light in a transparent dielectric medium. In optical fibers, Cerenkov radiation can also be generated due to the fiber’s dielectric components. Accordingly, the radiation-induced light signals can be obtained using the optical fibers without any scintillating material. In this study, we fabricated a multichannel, fiber-optic Cerenkov radiation sensor (FOCRS) system using silica optical fibers (SOFs), plastic optical fibers (POFs), an optical spectrometer, multi-anode photomultiplier tubes (MA-PMTs) and a scanning system to measure the light intensities of Cerenkov radiation induced by gamma rays. To evaluate the fading effects in optical fibers, the spectra of Cerenkov radiation generated in the SOFs and POFs were measured based on the irradiation time by using an optical spectrometer. In addition, we measured the longitudinal distribution of gamma rays emitted from the cylindrical type Co-60 source by using MA-PMTs. The result was also compared with the distribution of the electron flux calculated by using the Monte Carlo N-particle transport code (MCNPX).

  16. A longitudinal study of measures of walking in people with Alzheimer's Disease.

    PubMed

    Wittwer, Joanne E; Webster, Kate E; Menz, Hylton B

    2010-05-01

    Longitudinal gait measures may be used to provide baseline data for intervention studies. This has not previously been reported in people with Alzheimer's Disease. In this study measures of walking and their variability were recorded for 19 people with Alzheimer's Disease on two occasions 1 year apart. Matched controls were measured once. Variability was calculated using the coefficient of variation (CV). Effect size was calculated using Cohen's d. Gait was slower and more variable in the Alzheimer's Disease group compared to controls. Over 1 year there was a decrease in velocity (initial=103.9cm/s, follow-up=95.1cm/s; p<0.05, d=0.4) and stride length (initial=119.6cm, follow-up=112.5cm; p<0.05, d=0.34) and an increase in double support (initial=24.2%, follow-up=30.1%; p<0.05, d=0.99) and stride length variability (initial CV=3.5%, follow-up CV=4.6%; p<0.05, d=0.65). These changes occurred in mild as well as more severe Alzheimer's Disease. Future research should focus on reducing this decline early in the course of the disease in order to maintain physical independence for as long as possible.

  17. Factor structure and longitudinal measurement invariance of the demand control support model: an evidence from the Swedish Longitudinal Occupational Survey of Health (SLOSH).

    PubMed

    Chungkham, Holendro Singh; Ingre, Michael; Karasek, Robert; Westerlund, Hugo; Theorell, Töres

    2013-01-01

    To examine the factor structure and to evaluate the longitudinal measurement invariance of the demand-control-support questionnaire (DCSQ), using the Swedish Longitudinal Occupational Survey of Health (SLOSH). A confirmatory factor analysis (CFA) and multi-group confirmatory factor analysis (MGCFA) models within the framework of structural equation modeling (SEM) have been used to examine the factor structure and invariance across time. Four factors: psychological demand, skill discretion, decision authority and social support, were confirmed by CFA at baseline, with the best fit obtained by removing the item repetitive work of skill discretion. A measurement error correlation (0.42) between work fast and work intensively for psychological demands was also detected. Acceptable composite reliability measures were obtained except for skill discretion (0.68). The invariance of the same factor structure was established, but caution in comparing mean levels of factors over time is warranted as lack of intercept invariance was evident. However, partial intercept invariance was established for work intensively. Our findings indicate that skill discretion and decision authority represent two distinct constructs in the retained model. However removing the item repetitive work along with either work fast or work intensively would improve model fit. Care should also be taken while making comparisons in the constructs across time. Further research should investigate invariance across occupations or socio-economic classes.

  18. Mild cognitive impairment: baseline and longitudinal structural MR imaging measures improve predictive prognosis.

    PubMed

    McEvoy, Linda K; Holland, Dominic; Hagler, Donald J; Fennema-Notestine, Christine; Brewer, James B; Dale, Anders M

    2011-06-01

    To assess whether single-time-point and longitudinal volumetric magnetic resonance (MR) imaging measures provide predictive prognostic information in patients with amnestic mild cognitive impairment (MCI). This study was conducted with institutional review board approval and in compliance with HIPAA regulations. Written informed consent was obtained from all participants or the participants' legal guardians. Cross-validated discriminant analyses of MR imaging measures were performed to differentiate 164 Alzheimer disease (AD) cases from 203 healthy control cases. Separate analyses were performed by using data from MR images obtained at one time point or by combining single-time-point measures with 1-year change measures. Resulting discriminant functions were applied to 317 MCI cases to derive individual patient risk scores. Risk of conversion to AD was estimated as a continuous function of risk score percentile. Kaplan-Meier survival curves were computed for risk score quartiles. Odds ratios (ORs) for the conversion to AD were computed between the highest and lowest quartile scores. Individualized risk estimates from baseline MR examinations indicated that the 1-year risk of conversion to AD ranged from 3% to 40% (average group risk, 17%; OR, 7.2 for highest vs lowest score quartiles). Including measures of 1-year change in global and regional volumes significantly improved risk estimates (P = 001), with the risk of conversion to AD in the subsequent year ranging from 3% to 69% (average group risk, 27%; OR, 12.0 for highest vs lowest score quartiles). Relative to the risk of conversion to AD conferred by the clinical diagnosis of MCI alone, MR imaging measures yield substantially more informative patient-specific risk estimates. Such predictive prognostic information will be critical if disease-modifying therapies become available. http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.11101975/-/DC1. RSNA, 2011

  19. Measurement bias detection with Kronecker product restricted models for multivariate longitudinal data: an illustration with health-related quality of life data from thirteen measurement occasions.

    PubMed

    Verdam, Mathilde G E; Oort, Frans J

    2014-01-01

    Application of Kronecker product to construct parsimonious structural equation models for multivariate longitudinal data.A method for the investigation of measurement bias with Kronecker product restricted models.Application of these methods to health-related quality of life data from bone metastasis patients, collected at 13 consecutive measurement occasions.The use of curves to facilitate substantive interpretation of apparent measurement bias.Assessment of change in common factor means, after accounting for apparent measurement bias.Longitudinal measurement invariance is usually investigated with a longitudinal factor model (LFM). However, with multiple measurement occasions, the number of parameters to be estimated increases with a multiple of the number of measurement occasions. To guard against too low ratios of numbers of subjects and numbers of parameters, we can use Kronecker product restrictions to model the multivariate longitudinal structure of the data. These restrictions can be imposed on all parameter matrices, including measurement invariance restrictions on factor loadings and intercepts. The resulting models are parsimonious and have attractive interpretation, but require different methods for the investigation of measurement bias. Specifically, additional parameter matrices are introduced to accommodate possible violations of measurement invariance. These additional matrices consist of measurement bias parameters that are either fixed at zero or free to be estimated. In cases of measurement bias, it is also possible to model the bias over time, e.g., with linear or non-linear curves. Measurement bias detection with Kronecker product restricted models will be illustrated with multivariate longitudinal data from 682 bone metastasis patients whose health-related quality of life (HRQL) was measured at 13 consecutive weeks.

  20. Longitudinal measurement of chromatic dispersion along an optical fiber transmission system with a new correction factor

    NASA Astrophysics Data System (ADS)

    Abbasi, Madiha; Imran Baig, Mirza; Shafique Shaikh, Muhammad

    2013-12-01

    At present existence OTDR based techniques have become a standard practice for measuring chromatic dispersion distribution along an optical fiber transmission link. A constructive measurement technique has been offered in this paper, in which a four wavelength bidirectional optical time domain reflectometer (OTDR) has been used to compute the chromatic dispersion allocation beside an optical fiber transmission system. To improve the correction factor a novel formulation has been developed, which leads to an enhanced and defined measurement. The investigational outcomes obtained are in good harmony.

  1. On the Longitudinal Morphology of Zonal Irregularity Drift Measured using Networks of GPS Scintillation Monitors

    NASA Astrophysics Data System (ADS)

    Carrano, C. S.; Groves, K. M.; Valladares, C. E.; Delay, S. H.

    2014-12-01

    A complete characterization of field-aligned ionospheric irregularities responsible for the scintillation of satellite signals includes not only their spectral properties (power spectral strength, spectral index, anisotropy ratio, and outer-scale) but also their horizontal drift velocity. From a system impacts perspective, the horizontal drift velocity is important in that it dictates the rate of signal fading and also, to an extent, the level of phase fluctuations encountered by the receiver. From a physics perspective, studying the longitudinal morphology of zonal irregularity may lead to an improved understanding of the F region dynamo and regional electrodynamics at low latitudes. The irregularity drift at low latitudes is predominantly zonal and is most commonly measured by cross-correlating observations of satellite signals made by a pair of closely-spaced antennas. The AFRL-SCINDA network operates a small number of VHF spaced-antenna systems at low latitude stations for this purpose. A far greater number of GPS scintillation monitors are operated by AFRL-SCINDA (25-30) and the Low Latitude Ionospheric Sensor Network (35-50), but the receivers are situated too far apart to monitor the drift using cross-correlation techniques. In this paper, we present an alternative approach that leverages the weak scatter scintillation theory (Rino, Radio Sci., 1979) to infer the zonal irregularity drift from single-station GPS measurements of S4, sigma-phi, and the propagation geometry alone. Unlike the spaced-receiver technique, this technique requires assumptions for the height of the scattering layer (which introduces a bias in the drift estimates) and the spectral index of the irregularities (which affects the spread of the drift estimates about the mean). Nevertheless, theory and experiment show that the ratio of sigma-phi to S4 is less sensitive to these parameters than it is to the zonal drift, and hence the zonal drift can be estimated with reasonable accuracy. In

  2. Longitudinal measurement invariance in prospective oral health-related quality of life assessment.

    PubMed

    Reissmann, Daniel R; John, Mike T; Feuerstahler, Leah; Baba, Kazuyoshi; Szabó, Gyula; Čelebić, Asja; Waller, Niels

    2016-06-07

    Prospective assessments of oral health-related quality of life (OHRQoL) changes are prone to response shift effects when patients reconceptualize, reprioritize, or recalibrate the perceived meanings of OHRQoL test items. If this occurs, OHRQoL measurements are not "invariant" and may reflect changes in problem profiles or perceptions of OHRQoL test items. This suggests that response shift effects must be measured and controlled to achieve valid prospective OHRQoL measurement. The aim of this study was to quantify response shift effects of Oral Health Impact Profile (OHIP) scores in prospective studies of prosthodontic patients. Data came from the Dimensions of Oral Health-Related Quality of Life Project. The final sample included 554 patients who completed the OHIP questionnaire on two occasions: pre- and post-treatment. Only items that compose the 14-item OHIP were analyzed. Structural equation models that included pre- and post-treatment latent factors of OHRQoL with different across-occasion constraints for factor loadings, intercepts, and residual variances were fit to the data using confirmatory factor analysis. Data fit both the unconstrained model (RMSEA = .038, SRMR = .051, CFI = .92, TLI = .91) and the partially constrained model with freed residual variances (RMSEA = .037, SRMR = .064, CFI = .92, TLI = .92) well, meaning that the data are well approximated by a one-factor model at each occasion, and suggesting strong factorial across-occasion measurement invariance. The results provided cogent evidence for the absence of response shift in single factor OHIP models, indicating that longitudinal OHIP assessments of OHRQoL measure similar constructs across occasions.

  3. Longitudinal detection of ferromagnetic resonance using x-ray transmission measurements.

    PubMed

    Boero, G; Rusponi, S; Kavich, J; Rizzini, A Lodi; Piamonteze, C; Nolting, F; Tieg, C; Thiele, J-U; Gambardella, P

    2009-12-01

    We describe a setup for the x-ray detection of ferromagnetic resonance in the longitudinal geometry using element-specific transmission measurements. Thin magnetic film samples are placed in a static magnetic field collinear with the propagation direction of a polarized soft x-ray beam and driven to ferromagnetic resonance by a continuous wave microwave magnetic field perpendicular to it. The transmitted photon flux is measured both as a function of the x-ray photon energy and as a function of the applied static magnetic field. We report experiments performed on a 15 nm film of doped Permalloy (Ni(73)Fe(18)Gd(7)Co(2)) at the L(3)/L(2)-edges of Fe, Co, and Ni. The achieved ferromagnetic resonance sensitivity is about 0.1 monolayers/square root(Hz). The obtained results are interpreted in the framework of a conductivity tensor based formalism. The factors limiting the sensitivity as well as different approaches for the x-ray detection of ferromagnetic resonance are discussed.

  4. TIME-DEPENDENT PHASE SPACE MEASUREMENTS OF THE LONGITUDINALLY COMPRESSING BEAM IN NDCX-I

    SciTech Connect

    LBNL; Lidia, S.M.; Bazouin, G.; Seidl, P.A.

    2011-03-15

    The Neutralized Drift Compression Experiment (NDCXI) generates high intensity ion beams to explore Warm Dense Matter physics. A {approx}150 kV, {approx}500 ns modulating voltage pulse is applied to a {approx}300 kV, 5-10 {mu}s, 25 mA K+ ion beam across a single induction gap. The velocity modulated beam compresses longitudinally during ballistic transport along a space charge neutralizing plasma transport line, resulting in {approx}3A peak current with {approx}2-3 ns pulse durations (FWHM) at the target plane. Transverse final focusing is accomplished with a {approx}8 T, 10 cm long pulsed solenoid magnet. Time-dependent electrostatic focusing in the induction gap, and chromatic aberrations in the final focus optics limit the peak fluenceat the target plane for the compressed beam pulse. We report on time-dependent phase space measurements of the compressed pulse in the ballistic transport beamline, and measurement of the time-dependent radial impulses derived from the interaction of the beam and the induction gap voltage. We present results of start-to-end simulations to benchmark the experiments. Fast correction strategies are discussed with application to both NDCX-I and the soon to be commissioned NDCX-II accelerators.

  5. Measurement of the longitudinal spin structure of the proton by COMPASS

    NASA Astrophysics Data System (ADS)

    Korzenev, A.; Compass Collaboration

    2010-01-01

    The inclusive A and hadron double-spin asymmetries Apπ+, Apπ-, ApK+, ApK- measured at COMPASS (CERN SPS) in deep-inelastic scattering of a polarized muon beam off a polarized NH 3 solid target are presented. The results have been obtained with the full statistics collected in 2007 for the longitudinal target polarization. Proton asymmetries have been combined with published deuteron ones. An evaluation of the non-singlet spin-dependent structure function g1NS(x,Q) and its first moment, which confirms the validity of the Bjorken sum-rule, is presented. A LO evaluation of polarized quark densities is also presented. The use of the proton data allows to perform a full flavor separation and to extract individual helicity densities of u, d, u¯, d¯ and s quarks. All sea quark densities are found to be compatible with zero in the full range of the measurements.

  6. Longitudinal detection of ferromagnetic resonance using x-ray transmission measurements

    SciTech Connect

    Boero, G.; Rusponi, S.; Kavich, J.; Rizzini, A. Lodi; Piamonteze, C.; Nolting, F.; Tieg, C.; Thiele, J.-U.; Gambardella, P.

    2009-12-15

    We describe a setup for the x-ray detection of ferromagnetic resonance in the longitudinal geometry using element-specific transmission measurements. Thin magnetic film samples are placed in a static magnetic field collinear with the propagation direction of a polarized soft x-ray beam and driven to ferromagnetic resonance by a continuous wave microwave magnetic field perpendicular to it. The transmitted photon flux is measured both as a function of the x-ray photon energy and as a function of the applied static magnetic field. We report experiments performed on a 15 nm film of doped Permalloy (Ni{sub 73}Fe{sub 18}Gd{sub 7}Co{sub 2}) at the L{sub 3}/L{sub 2}-edges of Fe, Co, and Ni. The achieved ferromagnetic resonance sensitivity is about 0.1 monolayers/{radical}(Hz). The obtained results are interpreted in the framework of a conductivity tensor based formalism. The factors limiting the sensitivity as well as different approaches for the x-ray detection of ferromagnetic resonance are discussed.

  7. Predicting medical practices using various risk attitude measures.

    PubMed

    Massin, Sophie; Nebout, Antoine; Ventelou, Bruno

    2017-08-31

    This paper investigates the predictive power of several risk attitude measures on a series of medical practices. We elicit risk preferences on a sample of 1500 French general practitioners (GPs) using two different classes of tools: scales, which measure GPs' own perception of their willingness to take risks between 0 and 10; and lotteries, which require GPs to choose between a safe and a risky option in a series of hypothetical situations. In addition to a daily life risk scale that measures a general risk attitude, risk taking is measured in different domains for each tool: financial matters, GPs' own health, and patients' health. We take advantage of the rare opportunity to combine these multiple risk attitude measures with a series of self-reported or administratively recorded medical practices. We successively test the predictive power of our seven risk attitude measures on eleven medical practices affecting the GPs' own health or their patients' health. We find that domain-specific measures are far better predictors than the general risk attitude measure. Neither of the two classes of tools (scales or lotteries) seems to perform indisputably better than the other, except when we concentrate on the only non-declarative practice (prescription of biological tests), for which the classic money-lottery test works well. From a public health perspective, appropriate measures of willingness to take risks may be used to make a quick, but efficient, profiling of GPs and target them with personalized communications, or interventions, aimed at improving practices.

  8. Theory and practice of manual blood pressure measurement.

    PubMed

    Cork, Alison

    This article outlines the process of taking a manual blood pressure measurement. The author suggests that it is a skill that nursing students should be using in clinical practice rather than relying on automated monitors.

  9. Practical Software Measurement: Measuring for Process Management and Improvement,

    DTIC Science & Technology

    1997-04-01

    modify the processes so as to better meet business needs. • Assess the impacts and benefits gained, and compare these to the costs of changes made to...of control methods, and these causes were called assignable. Walter A. Shewhart, 1931 Variations due to assignable causes have marked impacts on...product characteristics and other measures of process performance.3 These impacts create significant changes in the patterns of variation. This is

  10. Longitudinal Analysis of Opioid Analgesic Dose and Diabetes Quality of Care Measures.

    PubMed

    Gautam, Santosh; Franzini, Luisa; Mikhail, Osama I; Chan, Wenyaw; Turner, Barbara J

    2015-11-01

    To examine associations of opioid analgesic dose with quality of care for diabetes mellitus. Longitudinal statewide cohort. Subjects with diabetes filled one or more prescriptions for Schedule II/III opioids for noncancer pain in Blue Cross Blue Shield of Texas from 2008 through 2012. Opioid dose and outcomes were assessed in 6-month intervals after first filled prescription. Two morphine equivalent dose measures were daily dose and quartiles of total dose from all filled prescriptions. In fixed effects models adjusted for clinical and treatment variables, associations of opioid measures were examined for five outcomes: hemoglobin A1c (HbA1c) test, low density lipoprotein cholesterol (LDL) test, any hospitalization, any diabetes-related preventable hospitalization, and any emergency department (ED) visit. All daily and total opioid doses were associated (P < 0.05) with poorer outcomes for all five measures. For HbA1c testing, adjusted odds ratios (AORs) were reduced by 19% for high daily dose (≥100 mg) and highest quartile total dose (>900 mg), respectively, vs no opioids but >900 mg total dose had the lowest AOR for LDL testing (0.74 [CI 0.68, 0.80]). The AORs of any hospitalization or diabetes-related hospitalization were, respectively, 8.19 (CI 7.21, 9.30) and 2.76 (CI 2.19, 3.48) for >900 mg total dose but only 6.22 (CI 4.94, 7.83) and 2.16 (CI 1.34, 3.48) for >100 mg daily dose. Both opioid measures had nonmonotonic associations with ED use. Daily opioid dose but especially total dose of opioids was strongly associated with poorer diabetes quality of care in a statewide cohort. Wiley Periodicals, Inc.

  11. Longitudinal measurement invariance of the metabolic syndrome: is the assessment of the metabolic syndrome stable over time?

    PubMed

    Barbosa-Leiker, Celestina; Wright, Bruce R; Burns, G Leonard; Parks, Craig D; Strand, Paul S

    2011-02-01

    Without verification of longitudinal measurement invariance, researchers cannot be certain whether observed change in the metabolic syndrome reflects true change or changes in assessment or structure of the construct over time. This research tested longitudinal measurement invariance of a 1-factor model of the metabolic syndrome during the course of 6 years. Tests of longitudinal measurement invariance (configural, metric, and scalar) were conducted on 604 men and women who participated in the Spokane Heart Study from 1996 to 2006. Metabolic syndrome indicators included body mass index, triglycerides, high-density lipoprotein, diastolic blood pressure, and fasting glucose. Sequential configural and metric invariance models demonstrated adequate model fit, but the scalar invariance model led to a decrement in fit. Therefore, the theoretical framework of the syndrome and the relationships between the syndrome construct and the indicators appear to be equivalent over time. However, observed values of the metabolic syndrome indicators may differ across time when there is a constant level of the syndrome. Because longitudinal invariance was not fully demonstrated, interpretation of change in the metabolic syndrome over time may be misleading because change may be partly attributable to measurement properties of the indicators. However, a cross-sectional 1-factor model of the metabolic syndrome is supported. Copyright © 2011 Elsevier Inc. All rights reserved.

  12. Improving the Rank Precision of Population Health Measures for Small Areas with Longitudinal and Joint Outcome Models

    PubMed Central

    Athens, Jessica K.; Remington, Patrick L.; Gangnon, Ronald E.

    2015-01-01

    Objectives The University of Wisconsin Population Health Institute has published the County Health Rankings since 2010. These rankings use population-based data to highlight health outcomes and the multiple determinants of these outcomes and to encourage in-depth health assessment for all United States counties. A significant methodological limitation, however, is the uncertainty of rank estimates, particularly for small counties. To address this challenge, we explore the use of longitudinal and pooled outcome data in hierarchical Bayesian models to generate county ranks with greater precision. Methods In our models we used pooled outcome data for three measure groups: (1) Poor physical and poor mental health days; (2) percent of births with low birth weight and fair or poor health prevalence; and (3) age-specific mortality rates for nine age groups. We used the fixed and random effects components of these models to generate posterior samples of rates for each measure. We also used time-series data in longitudinal random effects models for age-specific mortality. Based on the posterior samples from these models, we estimate ranks and rank quartiles for each measure, as well as the probability of a county ranking in its assigned quartile. Rank quartile probabilities for univariate, joint outcome, and/or longitudinal models were compared to assess improvements in rank precision. Results The joint outcome model for poor physical and poor mental health days resulted in improved rank precision, as did the longitudinal model for age-specific mortality rates. Rank precision for low birth weight births and fair/poor health prevalence based on the univariate and joint outcome models were equivalent. Conclusion Incorporating longitudinal or pooled outcome data may improve rank certainty, depending on characteristics of the measures selected. For measures with different determinants, joint modeling neither improved nor degraded rank precision. This approach suggests a simple

  13. Improving the Rank Precision of Population Health Measures for Small Areas with Longitudinal and Joint Outcome Models.

    PubMed

    Athens, Jessica K; Remington, Patrick L; Gangnon, Ronald E

    2015-01-01

    The University of Wisconsin Population Health Institute has published the County Health Rankings since 2010. These rankings use population-based data to highlight health outcomes and the multiple determinants of these outcomes and to encourage in-depth health assessment for all United States counties. A significant methodological limitation, however, is the uncertainty of rank estimates, particularly for small counties. To address this challenge, we explore the use of longitudinal and pooled outcome data in hierarchical Bayesian models to generate county ranks with greater precision. In our models we used pooled outcome data for three measure groups: (1) Poor physical and poor mental health days; (2) percent of births with low birth weight and fair or poor health prevalence; and (3) age-specific mortality rates for nine age groups. We used the fixed and random effects components of these models to generate posterior samples of rates for each measure. We also used time-series data in longitudinal random effects models for age-specific mortality. Based on the posterior samples from these models, we estimate ranks and rank quartiles for each measure, as well as the probability of a county ranking in its assigned quartile. Rank quartile probabilities for univariate, joint outcome, and/or longitudinal models were compared to assess improvements in rank precision. The joint outcome model for poor physical and poor mental health days resulted in improved rank precision, as did the longitudinal model for age-specific mortality rates. Rank precision for low birth weight births and fair/poor health prevalence based on the univariate and joint outcome models were equivalent. Incorporating longitudinal or pooled outcome data may improve rank certainty, depending on characteristics of the measures selected. For measures with different determinants, joint modeling neither improved nor degraded rank precision. This approach suggests a simple way to use existing information to

  14. Measures of the Effects of Agricultural Practices on Ecosystem Services

    SciTech Connect

    Dale, Virginia H; Polasky, Stephen

    2007-01-01

    Agriculture produces more than just crops. Agricultural practices have environmental impacts that affect a wide range of ecosystem services, including water quality, pollination, nutrient cycling, soil retention, carbon sequestration, and biodiversity conservation. In turn, ecosystem services affect agricultural productivity. Understanding the contribution of various agricultural practices to the range of ecosystem services would help inform choices about the most beneficial agricultural practices. To accomplish this, however, we must overcome a big challenge in measuring the impact of alternative agricultural practices on ecosystem services and of ecosystem services on agricultural production.

  15. Parental Strain, Mental Health Problems, and Parenting Practices: A Longitudinal Study.

    PubMed

    Borre, Alicia; Kliewer, Wendy

    2014-10-01

    Although poor parenting practices place youth living in under resourced communities at heightened risk for adjustment difficulties, less is known about what influences parenting practices in those communities. The present study examines prospective linkages between three latent constructs: parental strain, mental health problems and parenting practices. Parental victimization by community violence and life stressors were indicative of parental strain; depressive, anxious, and hostile symptoms were indicators of parental mental health; and parental knowledge of their child's activities and child disclosure were indicators of parenting practices. Interviews were conducted annually for 3 waves with 316 female caregivers (92% African American) parenting youth in low-income inner-city communities. Structural equation modeling revealed that parental strain, assessed at Wave 1, predicted changes in mental health problems one year later, which in turn predicted parenting practices at Wave 3. These results suggest that parental strain can compromise a caregiver's ability to parent effectively by impacting their mental health. Opportunities for intervention include helping caregivers process trauma and mental health problems associated with parental strain.

  16. Parental Strain, Mental Health Problems, and Parenting Practices: A Longitudinal Study

    PubMed Central

    Borre, Alicia; Kliewer, Wendy

    2014-01-01

    Although poor parenting practices place youth living in under resourced communities at heightened risk for adjustment difficulties, less is known about what influences parenting practices in those communities. The present study examines prospective linkages between three latent constructs: parental strain, mental health problems and parenting practices. Parental victimization by community violence and life stressors were indicative of parental strain; depressive, anxious, and hostile symptoms were indicators of parental mental health; and parental knowledge of their child's activities and child disclosure were indicators of parenting practices. Interviews were conducted annually for 3 waves with 316 female caregivers (92% African American) parenting youth in low-income inner-city communities. Structural equation modeling revealed that parental strain, assessed at Wave 1, predicted changes in mental health problems one year later, which in turn predicted parenting practices at Wave 3. These results suggest that parental strain can compromise a caregiver's ability to parent effectively by impacting their mental health. Opportunities for intervention include helping caregivers process trauma and mental health problems associated with parental strain. PMID:24976666

  17. Spectral Fluctuations of Incoherent Radiation And Measurement of Longitudinal Bunch Profile

    SciTech Connect

    Zolotorev, M.S.; Stupakov, G.V.; /SLAC

    2011-09-01

    A method for measurement of ultrashort beam current profile I{sub b}(t) is proposed that is based on detecting fluctuations of the spectral intensity P ({omega}) of single bunch incoherent radiation. We show that the variance of the Fourier transform of the spectrum is proportional to the convolution function of the beam current. After the convolution function is found, using phase retrieval technique one can restore the shape of the pulse in many practical cases.

  18. The relationship between accessory navicular and medial longitudinal arch: evaluation with a plantar pressure distribution measurement system.

    PubMed

    Kanatli, Ulunay; Yetkin, Haluk; Yalcin, Nadir

    2003-06-01

    This study included 92 patients with an accessory navicular (AN) noted on an anteroposterior roentgenography. This group was selected from 860 patients admitted to the authors' gait analysis laboratory. The medial longitudinal arch was evaluated by using an "arch index" calculated from the pressure picture obtained from a pressure distribution measurement system. The average arch index was 0.15 and there was no significant correlation between AN types and arch index. The study concluded that the presence and type of AN are not correlated with the height of the medial longitudinal arch of the foot and that AN is not associated with pes planus.

  19. The associations of large-for-gestational-age and infant feeding practices with children's body mass index z-score trajectories: the Early Childhood Longitudinal Study, Birth Cohort.

    PubMed

    Salahuddin, M; Pérez, A; Ranjit, N; Hoelscher, D M; Kelder, S H

    2017-10-01

    Very few studies have examined if high birth weight and infant feeding practices have implications for the trajectory of body mass index (BMI) growth across the early childhood period. The goal of this study was to assess if large-for-gestational-age (LGA) and infant feeding practices (exclusive breastfeeding for 6 months, and early introduction of complementary food prior to 4 months) are associated with BMI z-score trajectories over the early childhood period. Group-based trajectory modelling (GBTM) methods were employed to describe and classify developmental BMI z-score trajectories (the outcome of interest) in children from 9 months to 4 years of age (n = 4497) born to prenatal non-smoking mothers in the Early Childhood Longitudinal Study, Birth Cohort (2001-2005). Further analyses examined if the identified BMI z-score trajectories varied systematically with the exposures, LGA and specific infant feeding practices, after accounting for sociodemographic and other early-life factors. Two BMI z-score trajectory groups were identified: normal BMI z-score (56.2%) and high BMI z-score (43.8%). Children who were LGA infants had 2.3 times (risk ratio 95% confidence interval: 1.2, 4.5) greater risk of being in high BMI z-score group relative to normal BMI z-score group. BMI z-score trajectory groups did not differ by infant feeding practices, after controlling for LGA at birth. Membership in the high BMI z-score group was associated with LGA, but not with infant feeding practices. Healthcare professionals should provide early obesity counselling to parents of LGA infants so that parents can take appropriate obesity prevention measures for their children. © 2017 World Obesity Federation.

  20. "Collaborative-ready" students: Exploring factors that influence collaboration during a longitudinal interprofessional education practice experience.

    PubMed

    Rotz, Melissa E; Dueñas, Gladys G

    2016-01-01

    A goal of interprofessional education (IPE) is to prepare "collaborative-ready" healthcare professionals to ultimately improve health outcomes. The objective of our study was to explore student-reported factors that influence collaboration within our longitudinal IPE experience. Twenty-five first-year pharmacy students and 50 first-year medical students enrolled in IPE courses were invited to participate in three focus groups. Focus group responses were audio-recorded, transcribed verbatim, and applied to a qualitative thematic analysis. Eighteen students participated with six students in each group. Compared to the medical students, the pharmacy students were younger (22 vs. 26 years), had earned only a high school diploma, and had less healthcare experience. Emergent themes that students reported revealed various factors that can facilitate and inhibit collaboration among student participants. These findings can inform curricular redesign to focus on: clarifying provider roles, requiring ongoing preceptor development, enhancing course orientation, and coordinating student schedules to better prepare "collaborative-ready" students.

  1. Longitudinal Hemodynamic Measurements in Swine Heart Failure Using a Fully Implantable Telemetry System

    PubMed Central

    Choy, Jenny S.; Zhang, Zhen-Du; Pitsillides, Koullis; Sosa, Margo; Kassab, Ghassan S.

    2014-01-01

    Chronic monitoring of heart rate, blood pressure, and flow in conscious free-roaming large animals can offer considerable opportunity to understand the progression of cardiovascular diseases and can test new diagnostics and therapeutics. The objective of this study was to demonstrate the feasibility of chronic, simultaneous measurement of several hemodynamic parameters (left ventricular pressure, systemic pressure, blood flow velocity, and heart rate) using a totally implantable multichannel telemetry system in swine heart failure models. Two solid-state blood pressure sensors were inserted in the left ventricle and the descending aorta for pressure measurements. Two Doppler probes were placed around the left anterior descending (LAD) and the brachiocephalic arteries for blood flow velocity measurements. Electrocardiographic (ECG) electrodes were attached to the surface of the left ventricle to monitor heart rate. The telemeter body was implanted in the right side of the abdomen under the skin for approximately 4 to 6 weeks. The animals were subjected to various heart failure models, including volume overload (A-V fistula, n = 3), pressure overload (aortic banding, n = 2) and dilated cardiomyopathy (pacing-induced tachycardia, n = 3). Longitudinal changes in hemodynamics were monitored during the progression of the disease. In the pacing-induced tachycardia animals, the systemic blood pressure progressively decreased within the first 2 weeks and returned to baseline levels thereafter. In the aortic banding animals, the pressure progressively increased during the development of the disease. The pressure in the A-V fistula animals only showed a small increase during the first week and remained stable thereafter. The results demonstrated the ability of this telemetry system of long-term, simultaneous monitoring of blood flow, pressure and heart rate in heart failure models, which may offer significant utility for understanding cardiovascular disease

  2. Longitudinal hemodynamic measurements in swine heart failure using a fully implantable telemetry system.

    PubMed

    Choy, Jenny S; Zhang, Zhen-Du; Pitsillides, Koullis; Sosa, Margo; Kassab, Ghassan S

    2014-01-01

    Chronic monitoring of heart rate, blood pressure, and flow in conscious free-roaming large animals can offer considerable opportunity to understand the progression of cardiovascular diseases and can test new diagnostics and therapeutics. The objective of this study was to demonstrate the feasibility of chronic, simultaneous measurement of several hemodynamic parameters (left ventricular pressure, systemic pressure, blood flow velocity, and heart rate) using a totally implantable multichannel telemetry system in swine heart failure models. Two solid-state blood pressure sensors were inserted in the left ventricle and the descending aorta for pressure measurements. Two Doppler probes were placed around the left anterior descending (LAD) and the brachiocephalic arteries for blood flow velocity measurements. Electrocardiographic (ECG) electrodes were attached to the surface of the left ventricle to monitor heart rate. The telemeter body was implanted in the right side of the abdomen under the skin for approximately 4 to 6 weeks. The animals were subjected to various heart failure models, including volume overload (A-V fistula, n = 3), pressure overload (aortic banding, n = 2) and dilated cardiomyopathy (pacing-induced tachycardia, n = 3). Longitudinal changes in hemodynamics were monitored during the progression of the disease. In the pacing-induced tachycardia animals, the systemic blood pressure progressively decreased within the first 2 weeks and returned to baseline levels thereafter. In the aortic banding animals, the pressure progressively increased during the development of the disease. The pressure in the A-V fistula animals only showed a small increase during the first week and remained stable thereafter. The results demonstrated the ability of this telemetry system of long-term, simultaneous monitoring of blood flow, pressure and heart rate in heart failure models, which may offer significant utility for understanding cardiovascular disease progression and

  3. Green Space and Child Weight Status: Does Outcome Measurement Matter? Evidence from an Australian Longitudinal Study.

    PubMed

    Sanders, Taren; Feng, Xiaoqi; Fahey, Paul P; Lonsdale, Chris; Astell-Burt, Thomas

    2015-01-01

    To examine whether neighbourhood green space is beneficially associated with (i) waist circumference (WC) and (ii) waist-to-height ratio (WtHR) across childhood. Gender-stratified multilevel linear regressions were used to examine associations between green space and objective measures of weight status in the Longitudinal Study of Australian Children, a nationally representative source of data on 4,423 children aged 6 y to 13 y. WC and WtHR were measured objectively. Percentage green space within the local area of residence was calculated. Effect modification by age was explored, adjusting for socioeconomic confounding. Compared to peers with 0-5% green space locally, boys and girls with >40% green space tended to have lower WC (β boys  -1.15, 95% CI -2.44, 0.14; β girls  -0.21, 95% CI -1.47, 1.05) and WtHR (β boys  -0.82, 95% CI -1.65, 0.01; β girls  -0.32, 95% CI -1.13, 0.49). Associations among boys were contingent upon age (p  valuesage∗green  space < 0.001) and robust to adjustment for socioeconomic variables. The benefits of greener neighbourhoods appeared from age 7, with mean WC and WtHR for boys aged 13 y with >40% green space at 73.85 cm and 45.75% compared to those with 0-5% green space at 75.18 cm and 46.62%, respectively. Greener neighbourhoods appear beneficial to alternative child weight status measures, particularly among boys.

  4. A longitudinal study of neck and upper limb musculoskeletal disorders and alternative measures of vibration exposure.

    PubMed

    Bovenzi, Massimo; Prodi, Andrea; Mauro, Marcella

    2016-08-01

    To investigate the exposure-response relationships between alternative frequency weightings of hand-transmitted vibration (HTV) and neck and upper limb musculoskeletal disorders (MSDs) in a cohort of HTV workers. In a three-year longitudinal study, the occurrence of neck and upper limb MSDs was investigated in 249 HTV workers and 138 control men. In the HTV workers, MSDs were related to measures of daily vibration exposure expressed in terms of 8-h energy-equivalent frequency-weighted acceleration magnitude [A(8)]. To calculate A(8), the acceleration magnitudes of vibration were weighted by means of four alternative frequency weightings of HTV. The associations between MSDs, individual characteristics, physical work load other than vibration, and psychological strain were also investigated. The occurrence of upper limb MSDs was greater in the HTV workers than in the controls. After adjustment for potential confounders, the occurrence of elbow/forearm and wrist/hand MSDs increased with the increase in vibration exposure. A measure of model selection did not reveal any substantial difference in the performance of the alternative frequency weightings of HTV for the prediction of neck and upper limb MSDs. In the study population, age, hard physical work load, and poor psychological well-being were associated with both neck and upper limb MSDs. In this study, there was evidence for significant exposure-response relationships between HTV exposure and MSDs in the distal sites of the upper limbs. There were no differences in the prediction of neck and upper limb MSDs between measures of daily vibration exposure calculated with alternative frequency weightings of acceleration magnitude.

  5. The Impact of Residency Training on Physicians' AIDS-Related Treatment Practices: A Longitudinal Panel Study.

    ERIC Educational Resources Information Center

    Yedidia, Michael J.; Berry, Carolyn A.

    1999-01-01

    Study of 394 physicians graduating in 1989 from six New York medical schools found that certain residency-training factors had sustained effects on physician behavior in caring for AIDS (acquired immune deficiency syndrome) patients, but not on the number of patients treated. Determinants of treatment practice included residency environment,…

  6. Low-Income Mothers' Food Practices with Young Children: A Qualitative Longitudinal Study

    ERIC Educational Resources Information Center

    Harden, Jeni; Dickson, Adele

    2015-01-01

    Objective: Young children living in socioeconomically deprived areas of Scotland have an increased risk of becoming overweight or obese. To enhance understanding of the wider contexts within which family food practices are developed, this study examined the experiences of low-income mothers with young children. Design: Qualitative longitudinal…

  7. Organizational structure of the Croatian family practice: a longitudinal study based on routinely collected data.

    PubMed

    Keglević, Mladenka Vrcić; Balint, Ines; Cvetković, Ivica; Gaćina, Ana

    2014-12-01

    This study was undertaken with the main aim of determining the trends in the number of family doctors' (FD), gender and educational structure, working status and the number of patients per FD between 1995 and 2013. As the main source of data collection served the Croatian Health Service Yearbooks and Croatian Health Insurance Fund (CHIF) databases on practices and FDs contracting in 2013. Obtained results indicated that the number of contracted FDs increased until 2007, then decreased, and again increased until 2350 in 2013. Average number of patients on FDs list was 1987 in 2012. Less than 50% FDs were specialist in family medicine, 70.3% of them were self-employed with the CHIF contract, and 81% were women. 123 practices planned by the Network did not have contracting FD in 2013. The lack of FDs, the huge number of patients over the standard number, and the location of the missing practices within the rural communities, together make Croatian FM practices less accessible.

  8. Low-Income Mothers' Food Practices with Young Children: A Qualitative Longitudinal Study

    ERIC Educational Resources Information Center

    Harden, Jeni; Dickson, Adele

    2015-01-01

    Objective: Young children living in socioeconomically deprived areas of Scotland have an increased risk of becoming overweight or obese. To enhance understanding of the wider contexts within which family food practices are developed, this study examined the experiences of low-income mothers with young children. Design: Qualitative longitudinal…

  9. Parental feeding practices and child weight status in Mexican American families: A longitudinal analysis

    USDA-ARS?s Scientific Manuscript database

    Parental feeding practices are thought to influence children's weight status, through children's eating behavior and nutritional intake. However, because most studies have been cross-sectional, the direction of influence is unclear. Moreover, although obesity rates are high among Latino children, fe...

  10. Measurement of the longitudinal and circumferential muscular activity associated with peristalsis using a single fibre grating array

    NASA Astrophysics Data System (ADS)

    Arkwright, J. W.; Blenman, N. G.; Underhill, I. D.; Maunder, S. A.; Spencer, N. J.; Costa, M.; Brooks, S. J.; Szczesniak, M. M.; Dinning, P. G.

    2010-09-01

    Diagnostic catheters based on fibre Bragg gratings (FBG's) are proving to be highly effective for measurement of the muscular activity associated with peristalsis in the human gut. The primary muscular contractions that generate peristalsis are circumferential in nature; however, it has long been known that there is also a component of longitudinal contractility present, acting in harmony with the circumferential component to improve the overall efficiency of material movement. To date, there have been relatively few reports on the measurement or inference of longitudinal contractions in humans and all have been limited to detection at a single location only. This is due to the lack of a viable recording technique suitable for real-time in-vivo measurement of this type of activity over extended lengths of the gut. We report the detection of longitudinal motion in lengths of excised mammalian colon using an FBG technique that should be viable for similar detection in humans. The longitudinal sensors have been combined with our previously reported FBG pressure sensing elements to form a composite catheter that allows the relative phase between the two components to be detected. The catheter output has been validated using digital video mapping in an ex-vivo animal preparation using lengths of rabbit ileum.

  11. Adaptive quantification and longitudinal analysis of pulmonary emphysema with a hidden Markov measure field model.

    PubMed

    Hame, Yrjo; Angelini, Elsa D; Hoffman, Eric A; Barr, R Graham; Laine, Andrew F

    2014-07-01

    The extent of pulmonary emphysema is commonly estimated from CT scans by computing the proportional area of voxels below a predefined attenuation threshold. However, the reliability of this approach is limited by several factors that affect the CT intensity distributions in the lung. This work presents a novel method for emphysema quantification, based on parametric modeling of intensity distributions and a hidden Markov measure field model to segment emphysematous regions. The framework adapts to the characteristics of an image to ensure a robust quantification of emphysema under varying CT imaging protocols, and differences in parenchymal intensity distributions due to factors such as inspiration level. Compared to standard approaches, the presented model involves a larger number of parameters, most of which can be estimated from data, to handle the variability encountered in lung CT scans. The method was applied on a longitudinal data set with 87 subjects and a total of 365 scans acquired with varying imaging protocols. The resulting emphysema estimates had very high intra-subject correlation values. By reducing sensitivity to changes in imaging protocol, the method provides a more robust estimate than standard approaches. The generated emphysema delineations promise advantages for regional analysis of emphysema extent and progression.

  12. Longitudinal measurement equivalence of subjective language brokering experiences scale in Mexican American adolescents.

    PubMed

    Kim, Su Yeong; Hou, Yang; Shen, Yishan; Zhang, Minyu

    2017-04-01

    Language brokering occurs frequently in immigrant families and can have significant implications for the well-being of family members involved. The present study aimed to develop and validate a measure that can be used to assess multiple dimensions of subjective language brokering experiences among Mexican American adolescents. Participants were 557 adolescent language brokers (54.2% female, Mage.wave1 = 12.96, SD = .94) in Mexican American families. Using exploratory and confirmatory factor analyses, we were able to identify 7 reliable subscales of language brokering: linguistic benefits, socioemotional benefits, efficacy, positive parent-child relationships, parental dependence, negative feelings, and centrality. Tests of factorial invariance show that these subscales demonstrate, at minimum, partial strict invariance across time and across experiences of translating for mothers and fathers, and in most cases, also across adolescent gender, nativity, and translation frequency. Thus, in general, the means of the subscales and the relations among the subscales with other variables can be compared across these different occasions and groups. Tests of criterion-related validity demonstrated that these subscales correlated, concurrently and longitudinally, with parental warmth and hostility, parent-child alienation, adolescent family obligation, depressive symptoms, resilience, and life meaning. This reliable and valid subjective language brokering experiences scale will be helpful for gaining a better understanding of adolescents' language brokering experiences with their mothers and fathers, and how such experiences may influence their development. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  13. An alternative classification to mixture modeling for longitudinal counts or binary measures.

    PubMed

    Subtil, Fabien; Boussari, Olayidé; Bastard, Mathieu; Etard, Jean-François; Ecochard, René; Génolini, Christophe

    2017-02-01

    Classifying patients according to longitudinal measures, or trajectory classification, has become frequent in clinical research. The k-means algorithm is increasingly used for this task in case of continuous variables with standard deviations that do not depend on the mean. One feature of count and binary data modeled by Poisson or logistic regression is that the variance depends on the mean; hence, the within-group variability changes from one group to another depending on the mean trajectory level. Mixture modeling could be used here for classification though its main purpose is to model the data. The results obtained may change according to the main objective. This article presents an extension of the k-means algorithm that takes into account the features of count and binary data by using the deviance as distance metric. This approach is justified by its analogy with the classification likelihood. Two applications are presented with binary and count data to show the differences between the classifications obtained with the usual Euclidean distance versus the deviance distance.

  14. Alternative Measures of Teacher Performance. Policy-to-Practice Brief

    ERIC Educational Resources Information Center

    Potemski, Amy; Baral, Mahua; Meyer, Cassandra

    2011-01-01

    This Policy-to-Practice Brief introduces five current examples of measures of teacher performance. The goal is to assist regional comprehensive centers and state education agencies in building local capacity to incorporate the use of alternative measures of teacher performance into the overhaul of state evaluation systems--especially in states…

  15. An Empirical Study of Reporting Practices Concerning Measurement Validity

    ERIC Educational Resources Information Center

    Hogan, Thomas P.; Agnello, Jessica

    2004-01-01

    This study investigates the current research practice concerning reporting measurement validity evidence based on a sample of 696 research reports listed in the American Psychological Association's Directory of Unpublished Experimental Mental Measures. Only 55% of the reports included any type of validity evidence. This was a substantially lower…

  16. Longitudinal Measurement of Extracellular Matrix Rigidity in 3D Tumor Models Using Particle-tracking Microrheology

    PubMed Central

    El-Hamidi, Hamid; Celli, Jonathan P.

    2014-01-01

    The mechanical microenvironment has been shown to act as a crucial regulator of tumor growth behavior and signaling, which is itself remodeled and modified as part of a set of complex, two-way mechanosensitive interactions. While the development of biologically-relevant 3D tumor models have facilitated mechanistic studies on the impact of matrix rheology on tumor growth, the inverse problem of mapping changes in the mechanical environment induced by tumors remains challenging. Here, we describe the implementation of particle-tracking microrheology (PTM) in conjunction with 3D models of pancreatic cancer as part of a robust and viable approach for longitudinally monitoring physical changes in the tumor microenvironment, in situ. The methodology described here integrates a system of preparing in vitro 3D models embedded in a model extracellular matrix (ECM) scaffold of Type I collagen with fluorescently labeled probes uniformly distributed for position- and time-dependent microrheology measurements throughout the specimen. In vitro tumors are plated and probed in parallel conditions using multiwell imaging plates. Drawing on established methods, videos of tracer probe movements are transformed via the Generalized Stokes Einstein Relation (GSER) to report the complex frequency-dependent viscoelastic shear modulus, G*(ω). Because this approach is imaging-based, mechanical characterization is also mapped onto large transmitted-light spatial fields to simultaneously report qualitative changes in 3D tumor size and phenotype. Representative results showing contrasting mechanical response in sub-regions associated with localized invasion-induced matrix degradation as well as system calibration, validation data are presented. Undesirable outcomes from common experimental errors and troubleshooting of these issues are also presented. The 96-well 3D culture plating format implemented in this protocol is conducive to correlation of microrheology measurements with therapeutic

  17. A new visualization and conceptualization of categorical longitudinal development: measurement invariance and change.

    PubMed

    Boom, Jan

    2015-01-01

    The Overlapping Waves Model (OWM) is a metaphor introduced by Siegler (1996) to illustrate a typical sequence of increasing and decreasing use of strategies during development. Going beyond metaphor, a new model synthesized from Latent Growth Modeling (LGM) and Item Response Theory (IRT) will be presented to analyze such categorical longitudinal data. Use of strategies can be scored as a variable with only a few ordinal categories. IRT provides the means to relate the usage of strategies to position on an underlying developmental dimension. LGM allows to model movement of individuals along this dimension, acknowledging individual differences both in starting point and in speed of progress. Measuring and modeling such strategy development requires that at each time point the same categories are used, in the sense that item difficulties must remain invariant over time. Whether, discrimination can be relaxed is still an issue. The problem that had to be solved was disentangling the between-person-individual differences from real intra-individual developmental differences. Figures with polytomous or multi-category Item Characteristic Curves (ICC's) resemble the OWM in many respects. However, such figures are usually taken to represent inter-individual differences, whereas the OWM usually represents development (so intra-individual differences), and we cannot have both at the same time. The solution came from creating a framework with ability differences on one axis and the effect of time on another axis, resulting in a 3-D model. These (orthogonal) dimensions make it possible to adequately conceptualize measurement invariance in this complex context. As the result is difficult to conceptualize without extensive visualization, special 3-D figures will be used to illustrate and a dynamic (rotatable and scalable) version will be made available as Computable Document Format object (Mathematica). The model was successfully applied in several microgenetic studies.

  18. Longitudinal associations of phthalate exposures during childhood and body size measurements in young girls

    PubMed Central

    Deierlein, Andrea L.; Wolff, Mary S.; Pajak, Ashley; Pinney, Susan M.; Windham, Gayle C.; Galvez, Maida P.; Silva, Manori J.; Calafat, Antonia M.; Kushi, Lawrence H.; Biro, Frank M.; Teitelbaum, Susan L.

    2017-01-01

    Background Phthalates are environmental chemicals that may play a role in the development of obesity. Few studies have investigated longitudinal associations between postnatal phthalate exposures and subsequent anthropometric measurements in children. Methods We collected data as part of The Breast Cancer and Environment Research Program at three US sites. 1,239 girls, ages 6–8 years, were enrolled in 2004–2007. We categorized baseline phthalate exposures, assessed from creatinine-corrected urinary concentrations of low molecular weight phthalate metabolites as low, <78; medium, 78-<194; and high, ≥194 μg/g creatinine and of high molecular weight phthalates as low, <111; medium, 111–278; and high, ≥278 μg/g creatinine. Anthropometric measurements were collected through 2012 (n=1,017). Linear mixed effects regression estimated how baseline low and high molecular weight phthalate concentrations related to changes in girls’ body mass index (BMI), height, and waist circumference at ages 7 through 13 years. Results Low molecular weight phthalates were positively associated with gains in BMI and waist circumference. Predicted differences in BMI and waist circumference between girls with high versus low concentrations of low molecular weight phthalates increased from 0.56 (95% CI: −0.02, 1.1) to 1.2 (95%CI: 0.28, 2.1) kg/m2 and from 1.5 (95%CI: −0.38, 3.3) to 3.9 (95%CI: 1.3, 6.5) cm, respectively. High molecular weight phthalates were negatively associated with height but only among girls who were normal weight at baseline (BMI ≤85th percentile). Conclusion Phthalates, specifically low molecular weight phthalates, have small but detectable associations with girls’ anthropometric outcomes. Low molecular weight phthalates, showed stronger associations than other types of phthalates. PMID:27031039

  19. Impact of College-Administered Quality Practice Assessments: A Longitudinal Evaluation of Repeat Peer Assessments of Continuing Competence in Physiotherapists

    PubMed Central

    O'Donovan, Mary Jane; Campbell, Fiona

    2015-01-01

    ABSTRACT Purpose: The College of Physiotherapists of Ontario (CPO) developed its peer practice assessment (PA) process under statutory requirements for quality assurance. Each year, a small percentage of physiotherapists, most selected at random, undergo PA. To shed light on continuing competence, we report outcomes from physiotherapists who have had two PAs. Methods: Records were extracted for physiotherapists with two unrelated PAs. Demographic features, peer assessors' scores, and consequent outcome decisions were examined. Outcomes were examined cross-sectionally (vs. other PAs in the same time period) and longitudinally (within cohort). Results: Between 2004 and 2012, 117 Ontario physiotherapists underwent two unrelated PAs, typically 5–7 years apart. This cohort was representative of Ontario physiotherapists in terms of sex ratios, education, and years in practice. At the first PA (PA1), this cohort's outcomes were similar to those of other physiotherapists; at the second PA (PA2), they were better than others undergoing PA1 in the same period (p=0.02). The cohort's outcomes were better at PA2 than at PA1 (p<0.001). Conclusions: Physiotherapists are likely to meet professional standards in a repeat PA 5–7 years after an initial one. Additional research is required to identify risk factors for not meeting standards. The findings provide empirical evidence to guide ongoing development of the CPO's quality management program. PMID:25931670

  20. Underlying Factors of Family Literacy Practices as Antecedents of Reading Achievement: A Longitudinal, Factorial, Multiple Regression Study Using ECLS-K Data

    ERIC Educational Resources Information Center

    Fisher, Stacey Jonell

    2011-01-01

    The study had twofold purposes. The first one is to establish the underlying structure of family literacy practices at the different grade levels kindergarten, first, third, fifth, and eighth, for children who were followed in the Early Childhood Longitudinal Study, Kindergarten Class of 1998-1999 (ECLS-K). The second purpose is to investigate the…

  1. Maternal feeding styles and food parenting practices as predictors of longitudinal changes in weight status in Hispanic preschoolers from low-income families

    USDA-ARS?s Scientific Manuscript database

    The aim was to investigate the influence of feeding styles and food parenting practices on low-income children's weight status over time. Participants were 129 Latina parents and their Head Start children participating in a longitudinal study. Children were assessed at baseline (4 to 5 years old) an...

  2. Measuring Nursing Practice Models using Multi-Attribute Utility theory.

    PubMed

    Brennan, P F; Anthony, M K

    2000-10-01

    Nursing Practice Models (NPMs) represent the structural and contextual features that exist within any group practice of nursing. Currently, measurement of NPMs relies on costly and nonreproducible global judgments by experts. Quantitative measurement techniques are needed to provide a useful evaluation of nursing practice. Guided by Multi-Attribute Utility theory (MAU theory), an expert panel identified 24 factors representative of N PMs. The factors became elements in a computational index that, when summed, assigns a score to a given nursing unit reflecting the extent to which that unit's nursing practice model achieves the nursing professional ideal. Initial validation of the index and its elements consisted of comparing assessments of 40 nursing units generated by the index with a global evaluation provided by each of the expert panelists who proposed the model factors. Pearson correlations between the index-generated scores and the global assigned scores provided evidence supporting the preliminary validation of the index.

  3. First Measurements of the Longitudinal Bunch Profile at SLAC Using Coherent Smith-Purcell Radiation at 28GeV

    SciTech Connect

    Blackmore, V.; Doucas, G.; Ottewell, B.; Perry, C.; Kimmitt, M.F.; Arnold, R.; Molloy, S.; Woods, M.; /SLAC

    2011-11-02

    Coherent Smith-Purcell radiation has been demonstrated as a technique for measuring the longitudinal profile of charged particles bunches in the low to intermediate energy range. However, with the advent of the International Linear Collider, the need has arisen for a non-invasive method of measuring the bunch profile at extremely high energies. Smith-Purcell radiation has been used for the first time in the multi-GeV regime to measure the longitudinal profile of the 28GeV SLAC beam. The experiment has both successfully determined the bunch length, and has also demonstrated its sensitivity to bunch profile changes. The challenges associated with this technique, and its prospects as a diagnostic tool are reported here.

  4. a Measurement of the Longitudinal-Transverse Interference Structure Function from the Deuterium

    NASA Astrophysics Data System (ADS)

    McIlvain, Thomas Robert

    This thesis describes the results of a deuterium electrodisintegration experiment performed at the Bates Linear Accelerator Center. We scattered electrons from deuterium nuclei in a CD_2 target, detecting the scattered electron and the ejected proton in coincidence. By measuring the D(e,e'p) cross section at two different angles of proton emission, with fixed values of the energy transfer, omega ~ 109 MeV, and momentum transfer, q ~ 400 MeV/c, we extracted the longitudinal-transverse interference structure function, R_{LT }. R_{LT} is one of the four structure functions that contribute to the unpolarized coincidence cross section. We performed the experiment in the Bates North Hall using the Energy Loss Spectrometer System (ELSSY) to detect electrons and the prototype Out-Of-Plane Spectrometer (OOPS) to detect protons. Electrons of incident energies 576 MeV were scattered at angles of 44^circ. Protons were detected in non-parallel kinematics at angles of -64.7^circ (theta_{pq } ~ 11^circ 'right' of vec q) and -42.9^ circ (theta_{pq} ~ 11^circ 'left' of vec q). In order to maximize the statistical precision of the measurements, the cross sections and the structure function are averaged over a region of 81 to 106 MeV/c in missing momentum, p_{m}. We compared the data to several calculations done by H. Arenhoevel. The most interesting physics was seen in the observable A_phi, the left-right asymmetry or difference/sum of the cross sections. A_phi was the only measured observable with minimal theoretical uncertainty. Thus, the theory-data comparison using A_phi was the most telling. A_phi was measured with statistical and systematic uncertainties of 12.8% and 10.8%, respectively. At this level of precision, it was concluded that the data showed a preference for the Arenhoevel relativistic full calculation over his non -relativistic full calculation. (Copies available exclusively from MIT Libraries, Rm. 14-0551, Cambridge, MA 02139-4307. Ph. 617 -253-5668; Fax 617-253-1690.).

  5. Maternal Feeding Styles and Food Parenting Practices as Predictors of Longitudinal Changes in Weight Status in Hispanic Preschoolers from Low-Income Families.

    PubMed

    Hughes, Sheryl O; Power, Thomas G; O'Connor, Teresia M; Orlet Fisher, Jennifer; Chen, Tzu-An

    2016-01-01

    Objective. The aim was to investigate the influence of feeding styles and food parenting practices on low-income children's weight status over time. Method. Participants were 129 Latina parents and their Head Start children participating in a longitudinal study. Children were assessed at baseline (4 to 5 years old) and again eighteen months later. At each time point, parents completed questionnaires and height and weight measures were taken on the child. Results. The indulgent feeding style (parent-report at baseline) was associated with increased child BMI z-score eighteen months later compared to other feeding styles. Authoritative, authoritarian, and uninvolved feeding styles were not significantly associated with increased child BMI z-score. Child BMI z-score at Time 1 (strongest) and maternal acculturation were positive predictors of child BMI z-score at Time 2. Maternal use of restriction positively predicted and maternal monitoring negatively predicted Time 2 BMI z-score, but only when accounting for feeding styles. Conclusion. This is the first study to investigate the impact of feeding styles on child weight status over time. Results suggest that indulgent feeding predicts later increases in children's weight status. The interplay between feeding styles and food parenting practices in influencing child weight status needs to be further explored.

  6. Maternal Feeding Styles and Food Parenting Practices as Predictors of Longitudinal Changes in Weight Status in Hispanic Preschoolers from Low-Income Families

    PubMed Central

    O'Connor, Teresia M.; Orlet Fisher, Jennifer

    2016-01-01

    Objective. The aim was to investigate the influence of feeding styles and food parenting practices on low-income children's weight status over time. Method. Participants were 129 Latina parents and their Head Start children participating in a longitudinal study. Children were assessed at baseline (4 to 5 years old) and again eighteen months later. At each time point, parents completed questionnaires and height and weight measures were taken on the child. Results. The indulgent feeding style (parent-report at baseline) was associated with increased child BMI z-score eighteen months later compared to other feeding styles. Authoritative, authoritarian, and uninvolved feeding styles were not significantly associated with increased child BMI z-score. Child BMI z-score at Time 1 (strongest) and maternal acculturation were positive predictors of child BMI z-score at Time 2. Maternal use of restriction positively predicted and maternal monitoring negatively predicted Time 2 BMI z-score, but only when accounting for feeding styles. Conclusion. This is the first study to investigate the impact of feeding styles on child weight status over time. Results suggest that indulgent feeding predicts later increases in children's weight status. The interplay between feeding styles and food parenting practices in influencing child weight status needs to be further explored. PMID:27429801

  7. [Formula: see text]Practice effects and longitudinal cognitive change in clinically normal older adults differ by Alzheimer imaging biomarker status.

    PubMed

    Machulda, Mary M; Hagen, Clint E; Wiste, Heather J; Mielke, Michelle M; Knopman, David S; Roberts, Rosebud O; Vemuri, Prashanthi; Lowe, Val J; Jack, Clifford R; Petersen, Ronald C

    2017-01-01

    The objective of this study was to examine practice effects and longitudinal cognitive change in 190 clinically normal elderly classified according to a two-feature biomarker model for Alzheimer's disease. All participants completed neuropsychological testing, MRI, FDG-PET, and PiB-PET at their baseline evaluation. We divided participants into four groups based on neuroimaging measures of amyloid (A+ or A-) and neurodegeneration (N+ or N-) and reexamined cognition at 15- and 30-month intervals. The A-N- group showed significant improvements in the memory and global scores. The A+N- group also showed significant improvements in the memory and global scores as well as attention. The A-N+ group showed a significant decline in attention at 30 months. The A+N+ group showed significant improvements in memory and the global score at 15 months followed by a significant decline in the global score at 30 months. Amyloidosis in the absence of neurodegeneration did not have an adverse impact on practice effects or the 30-month cognitive trajectories. In contrast, participants with neurodegeneration (either A-N+ or A+N+) had worse performance at the 30-month follow-up. Our results show that neurodegeneration has a more deleterious effect on cognition than amyloidosis in clinically normal individuals.

  8. Measuring Adherence to Practice Guidelines for the Management of Hypertension

    PubMed Central

    Milchak, Jessica L.; Carter, Barry L.; Ardery, Gail; James, Paul A.

    2006-01-01

    Adherence to practice guidelines is frequently used as a measure of quality of care. Numerous studies have evaluated physician adherence to hypertension guidelines by prescription data, physician survey data, or medical record review. However, most have methodological limitations that might underestimate physician adherence. Accurate and meaningful characterization of adherence rests on evaluation of varied components of hypertension care, use of explicit validated performance measures, incorporation of implicit and explicit review, and linkage of process measures to blood pressure outcomes. PMID:15381676

  9. Measuring student engagement in science classrooms: An investigation of the contextual factors and longitudinal outcomes

    NASA Astrophysics Data System (ADS)

    Spicer, Justina Judy

    This dissertation includes three separate but related studies that examine the different dimensions of student experiences in science using data from two different datasets: the High School Longitudinal Study of 2009 (HSLS:09), and a dataset constructed using the Experience Sampling Method (ESM). This mixed-dataset approach provides a unique perspective on student engagement and the contexts in which it exists. Engagement is operationalized across the three studies using aspects of flow theory to evaluate how the challenges in science classes are experienced at the student level. The data provides information on a student's skill-level and efficacy during the challenge, as well as their interest level and persistence. The data additionally track how situations contribute to optimal learning moments, along with longitudinal attitudes and behaviors towards science. In the first part of this study, the construct of optimal moments is explored using in the moment data from the ESM dataset. Several different measures of engagement are tested and validated to uncover relationships between various affective states and optimal learning experiences with a focus on science classrooms. Additional analyses include investigating the links between in the moment engagement (situational), and cross-situational (stable) measures of engagement in science. The second part of this dissertation analyzes the ESM data in greater depth by examining how engagement varies across students and their contextual environment. The contextual characteristics associated with higher engagement levels are evaluated to see if these conditions hold across different types of students. Chapter three more thoroughly analyzes what contributes to students persisting through challenging learning moments, and the variation in levels of effort put forth when facing difficulty while learning in science. In chapter four, this dissertation explores additional outcomes associated with student engagement in science

  10. Measuring Cultural Socialization Attitudes and Behaviors of Mexican-Origin Mothers With Young Children: A Longitudinal Investigation.

    PubMed

    Derlan, Chelsea L; Umaña-Taylor, Adriana J; Toomey, Russell B; Jahromi, Laudan B; Updegraff, Kimberly A

    2016-07-01

    We describe the development and psychometric testing of the Cultural Socialization Behaviors Measure (CSBM) and the Cultural Socialization Attitudes Measure (CSAM). The CSBM assesses cultural socialization behaviors that parents use with young children, and the CSAM assesses the attitudes that parents have regarding the importance of socializing their young children about their culture. Both measures demonstrated strong reliability, validity, and cross-language equivalence (i.e., Spanish and English) among a sample of 204 Mexican-origin young mothers (Mage = 20.94 years, SD = 1.01) with 4-year-old children. In addition, the measures demonstrated longitudinal equivalence when children were 4 and 5 years of age.

  11. Differences in physical aging measured by walking speed: evidence from the English Longitudinal Study of Ageing.

    PubMed

    Weber, Daniela

    2016-01-28

    Physical functioning and mobility of older populations are of increasing interest when populations are aging. Lower body functioning such as walking is a fundamental part of many actions in daily life. Limitations in mobility threaten independent living as well as quality of life in old age. In this study we examine differences in physical aging and convert those differences into the everyday measure of single years of age. We use the English Longitudinal Study of Ageing, which was collected biennially between 2002 and 2012. Data on physical performance, health as well as information on economics and demographics of participants were collected. Lower body performance was assessed with two timed walks at normal pace each of 8 ft (2.4 m) of survey participants aged at least 60 years. We employed growth curve models to study differences in physical aging and followed the characteristic-based age approach to illustrate those differences in single years of age. First, we examined walking speed of about 11,700 English individuals, and identified differences in aging trajectories by sex and other characteristics (e.g. education, occupation, regional wealth). Interestingly, higher educated and non-manual workers outperformed their counterparts for both men and women. Moreover, we transformed the differences between subpopulations into single years of age to demonstrate the magnitude of those gaps, which appear particularly high at early older ages. This paper expands research on aging and physical performance. In conclusion, higher education provides an advantage in walking of up to 15 years for men and 10 years for women. Thus, enhancements in higher education have the potential to ensure better mobility and independent living in old age for a longer period.

  12. Measurement invariance of an instrument assessing sustainability of school-based universal behavior practices.

    PubMed

    Mercer, Sterett H; McIntosh, Kent; Strickland-Cohen, M Kathleen; Horner, Robert H

    2014-06-01

    The purpose of the study was to examine the extent to which the School-Wide Universal Behavior Sustainability Index: School Teams (SUBSIST; McIntosh, Doolittle, Vincent, Horner, & Ervin, 2009), a measure of school and district contextual factors that promote the sustainability of school practices, demonstrated measurement invariance across groups of schools that differed in length of time implementing school-wide Positive Behavioral Interventions and Supports (PBIS; Sugai & Horner, 2009), student ethnic composition, and student socioeconomic status (SES). School PBIS team members and district coaches representing 860 schools in 14 U.S. states completed the SUBSIST. Findings supported strong measurement invariance, for all items except 1, of a model with two school-level factors (School Priority and Team Use of Data) and 2 district-level factors (District Priority and Capacity Building) across groups of schools at initial implementation, institutionalization, and sustainability phases of PBIS implementation. Schools in the sustainability phase were rated significantly higher on School Priority and Team Use of Data than schools in initial implementation. Strong measurement invariance held across groups of schools that differed in student ethnicity and SES. The findings regarding measurement invariance are important for future longitudinal investigations of factors that may promote the sustained implementation of school practices. PsycINFO Database Record (c) 2014 APA, all rights reserved.

  13. Practical relevance of standardized disk and drive measurements

    NASA Astrophysics Data System (ADS)

    Gerger, Scott A.

    1999-11-01

    Literally hundreds of parameters have been specified for measuring Compact Disc (CD) and Digital Video Disc (DVD) characteristics but virtually none for drive performance. For the hundreds of optical disc characteristics, there are many differing methods for measuring each one. After having chosen the 'best' methods for measuring the disc characteristics and conducting the measurements, conformance to the industry specifications (de-facto standards) must be judged. The practical relevance of the relationships between disc parameters, measurement methods, and drive performance must be understood and managed such that the value experienced by the customer is preserved.

  14. Practical measures of integrated information for time-series data.

    PubMed

    Barrett, Adam B; Seth, Anil K

    2011-01-20

    A recent measure of 'integrated information', Φ(DM), quantifies the extent to which a system generates more information than the sum of its parts as it transitions between states, possibly reflecting levels of consciousness generated by neural systems. However, Φ(DM) is defined only for discrete Markov systems, which are unusual in biology; as a result, Φ(DM) can rarely be measured in practice. Here, we describe two new measures, Φ(E) and Φ(AR), that overcome these limitations and are easy to apply to time-series data. We use simulations to demonstrate the in-practice applicability of our measures, and to explore their properties. Our results provide new opportunities for examining information integration in real and model systems and carry implications for relations between integrated information, consciousness, and other neurocognitive processes. However, our findings pose challenges for theories that ascribe physical meaning to the measured quantities.

  15. Practical Measures of Integrated Information for Time-Series Data

    PubMed Central

    Barrett, Adam B.; Seth, Anil K.

    2011-01-01

    A recent measure of ‘integrated information’, ΦDM, quantifies the extent to which a system generates more information than the sum of its parts as it transitions between states, possibly reflecting levels of consciousness generated by neural systems. However, ΦDM is defined only for discrete Markov systems, which are unusual in biology; as a result, ΦDM can rarely be measured in practice. Here, we describe two new measures, ΦE and ΦAR, that overcome these limitations and are easy to apply to time-series data. We use simulations to demonstrate the in-practice applicability of our measures, and to explore their properties. Our results provide new opportunities for examining information integration in real and model systems and carry implications for relations between integrated information, consciousness, and other neurocognitive processes. However, our findings pose challenges for theories that ascribe physical meaning to the measured quantities. PMID:21283779

  16. Generating Rasch-based activity of daily living measures from the Spinal Cord Injury Longitudinal Aging Study.

    PubMed

    Li, C-Y; Velozo, C A; Hong, I; Li, C; Newman, J C; Krause, J S

    2017-09-12

    Retrospective Longitudinal Study. (1) To determine whether the Spinal Cord Injury Activities of Daily Living (SCI_ADL) measure shows adequate item-level and precision psychometrics; (2) to investigate whether the SCI_ADL measure effectively detects ADL changes across time; (3) to describe self-care task(s) participants can and cannot do across time. Two Midwestern hospitals and 1 Southeastern specialty hospital in 1993. All participants were adults with traumatic SCI of at least 1-year duration at enrollment. We used 20-year (1993-2013) retrospective longitudinal data and categorized participants into three injury levels: C1-C4 (cervical; n=50), C5-C8 (n=126) and T1-S5 (thoracic, lumbar and sacral; n=168). We first examined psychometrics of the SCI_ADL with factor and Rasch analyses; then we investigated longitudinal change of SCI_ADL scores at three time points over 20 years (1993, 2003 and 2013) using generalized linear mixed modeling and post hoc analyses. The SCI_ADL measure demonstrated unidimensionality, person strata of 2.9, high Cronbach's α (0.93) and fair person reliability (0.76). T1-S5 had the highest measures, following C5-C8 and C1-C4 at three time points (P<0.05). The C1-C4 and T1-S5 groups showed significant decreases from 2003 to 2013; however, none of the three groups showed significant differences from 1993 to 2003 (P<0.05). The SCI_ADL measure could detect longitudinal ADL changes of the population with SCI across time. The C1-C4 group decreased the most in ADLs, indicating higher need of long-term services and rehabilitation.Spinal Cord advance online publication, 12 September 2017; doi:10.1038/sc.2017.99.

  17. Projected impact of the ICD-10-CM/PCS conversion on longitudinal data and the Joint Commission Core Measures.

    PubMed

    Fenton, Susan H; Benigni, Mary Sue

    2014-01-01

    The transition from ICD-9-CM to ICD-10-CM/PCS is expected to result in longitudinal data discontinuities, as occurred with cause-of-death in 1999. The General Equivalence Maps (GEMs), while useful for suggesting potential maps do not provide guidance regarding the frequency of any matches. Longitudinal data comparisons can only be reliable if they use comparability ratios or factors which have been calculated using records coded in both classification systems. This study utilized 3,969 de-identified dually coded records to examine raw comparability ratios, as well as the comparability ratios between the Joint Commission Core Measures. The raw comparability factor results range from 16.216 for Nicotine dependence, unspecified, uncomplicated to 118.009 for Chronic obstructive pulmonary disease, unspecified. The Joint Commission Core Measure comparability factor results range from 27.15 for Acute Respiratory Failure to 130.16 for Acute Myocardial Infarction. These results indicate significant differences in comparability between ICD-9-CM and ICD-10-CM code assignment, including when the codes are used for external reporting such as the Joint Commission Core Measures. To prevent errors in decision-making and reporting, all stakeholders relying on longitudinal data for measure reporting and other purposes should investigate the impact of the conversion on their data.

  18. Projected Impact of the ICD-10-CM/PCS Conversion on Longitudinal Data and the Joint Commission Core Measures

    PubMed Central

    Fenton, Susan H.; Benigni, Mary Sue

    2014-01-01

    The transition from ICD-9-CM to ICD-10-CM/PCS is expected to result in longitudinal data discontinuities, as occurred with cause-of-death in 1999. The General Equivalence Maps (GEMs), while useful for suggesting potential maps do not provide guidance regarding the frequency of any matches. Longitudinal data comparisons can only be reliable if they use comparability ratios or factors which have been calculated using records coded in both classification systems. This study utilized 3,969 de-identified dually coded records to examine raw comparability ratios, as well as the comparability ratios between the Joint Commission Core Measures. The raw comparability factor results range from 16.216 for Nicotine dependence, unspecified, uncomplicated to 118.009 for Chronic obstructive pulmonary disease, unspecified. The Joint Commission Core Measure comparability factor results range from 27.15 for Acute Respiratory Failure to 130.16 for Acute Myocardial Infarction. These results indicate significant differences in comparability between ICD-9-CM and ICD-10-CM code assignment, including when the codes are used for external reporting such as the Joint Commission Core Measures. To prevent errors in decision-making and reporting, all stakeholders relying on longitudinal data for measure reporting and other purposes should investigate the impact of the conversion on their data. PMID:25214824

  19. Measurement of Single- and Double-Spin Asymmetries in Deep Inelastic Pion Electroproduction with a Longitudinally Polarized Target

    NASA Astrophysics Data System (ADS)

    Avakian, H.; Bosted, P.; Burkert, V. D.; Elouadrhiri, L.; Adhikari, K. P.; Aghasyan, M.; Amaryan, M.; Anghinolfi, M.; Baghdasaryan, H.; Ball, J.; Battaglieri, M.; Bedlinskiy, I.; Biselli, A. S.; Branford, D.; Briscoe, W. J.; Brooks, W.; Carman, D. S.; Casey, L.; Cole, P. L.; Collins, P.; Crabb, D.; Crede, V.; D'Angelo, A.; Daniel, A.; Dashyan, N.; de Vita, R.; de Sanctis, E.; Deur, A.; Dey, B.; Dhamija, S.; Dickson, R.; Djalali, C.; Dodge, G.; Doughty, D.; Dupre, R.; El Alaoui, A.; Eugenio, P.; Fegan, S.; Fersch, R.; Forest, T. A.; Fradi, A.; Gabrielyan, M. Y.; Gavalian, G.; Gevorgyan, N.; Gilfoyle, G. P.; Giovanetti, K. L.; Girod, F. X.; Gohn, W.; Gothe, R. W.; Griffioen, K. A.; Guidal, M.; Guler, N.; Guo, L.; Hafidi, K.; Hakobyan, H.; Hanretty, C.; Hassall, N.; Heddle, D.; Hicks, K.; Holtrop, M.; Ilieva, Y.; Ireland, D. G.; Isupov, E. L.; Jawalkar, S. S.; Jo, H. S.; Joo, K.; Keller, D.; Khandaker, M.; Khetarpal, P.; Kim, W.; Klein, A.; Klein, F. J.; Konczykowski, P.; Kubarovsky, V.; Kuhn, S. E.; Kuleshov, S. V.; Kuznetsov, V.; Livingston, K.; Lu, H. Y.; Markov, N.; Mayer, M.; Martinez, D.; McAndrew, J.; McCracken, M. E.; McKinnon, B.; Meyer, C. A.; Mineeva, T.; Mirazita, M.; Mokeev, V.; Moreno, B.; Moriya, K.; Morrison, B.; Moutarde, H.; Munevar, E.; Nadel-Turonski, P.; Nasseripour, R.; Niccolai, S.; Niculescu, G.; Niculescu, I.; Niroula, M. R.; Osipenko, M.; Ostrovidov, A. I.; Paremuzyan, R.; Park, K.; Park, S.; Pasyuk, E.; Anefalos Pereira, S.; Perrin, Y.; Pisano, S.; Pogorelko, O.; Price, J. W.; Procureur, S.; Prok, Y.; Protopopescu, D.; Raue, B. A.; Ricco, G.; Ripani, M.; Rosner, G.; Rossi, P.; Sabatié, F.; Saini, M. S.; Salamanca, J.; Salgado, C.; Schumacher, R. A.; Seder, E.; Seraydaryan, H.; Sharabian, Y. G.; Sober, D. I.; Sokhan, D.; Stepanyan, S. S.; Stepanyan, S.; Stoler, P.; Strauch, S.; Suleiman, R.; Taiuti, M.; Tedeschi, D. J.; Tkachenko, S.; Ungaro, M.; Vernarsky, B.; Vineyard, M. F.; Voutier, E.; Watts, D. P.; Weinstein, L. B.; Weygand, D. P.; Wood, M. H.; Zhang, J.; Zhao, B.; Zhao, Z. W.

    2010-12-01

    We report the first measurement of the transverse momentum dependence of double-spin asymmetries in semi-inclusive production of pions in deep-inelastic scattering off the longitudinally polarized proton. Data have been obtained using a polarized electron beam of 5.7 GeV with the CLAS detector at the Jefferson Lab (JLab). Modulations of single spin asymmetries over the azimuthal angle between lepton scattering and hadron production planes ϕ have been measured over a wide kinematic range in Bjorken x and virtual photon squared four-momentum Q2. A significant nonzero sin⁡2ϕ single spin asymmetry was observed for the first time indicating strong spin-orbit correlations for transversely polarized quarks in the longitudinally polarized proton.

  20. Longitudinal Double-Spin Asymmetry Measurements in p+p and Their Limitation by Systematic Uncertainty in Relative Luminosity

    NASA Astrophysics Data System (ADS)

    Manion, Andrew

    2012-03-01

    We present longitudinal double-spin asymmetries ALL in neutral 0̂ production in the PHENIX detector at RHIC. This measurement has been shown to constrain the gluon spin contribution to the proton, δG. We will also discuss the main systematic uncertainty, which originates from the relative luminosity of the different spin states in RHIC, and new ways to possibly understand the source of this uncertainty.

  1. Compressibility effects on the longitudinal stability and control of a pursuit-type airplane as measured in flight

    NASA Technical Reports Server (NTRS)

    Turner, William N; Steffen, Paul J; Clousing, Lawrence A

    1946-01-01

    Measurements of the longitudinal stability and control of a pursuit-type airplane were made in flight up to a Mach number of 0.78. The data are presented in the form of curves showing the variation, with center-of-gravity position, dynamic pressure, and Mach number, of the stick-fixed and stick-free stability, control, and balance of the airplane.

  2. Measurement of longitudinal spin asymmetries for weak boson production in polarized proton-proton collisions at RHIC.

    PubMed

    Adamczyk, L; Adkins, J K; Agakishiev, G; Aggarwal, M M; Ahammed, Z; Alekseev, I; Alford, J; Anson, C D; Aparin, A; Arkhipkin, D; Aschenauer, E C; Averichev, G S; Balewski, J; Banerjee, A; Beavis, D R; Bellwied, R; Bhasin, A; Bhati, A K; Bhattarai, P; Bichsel, H; Bielcik, J; Bielcikova, J; Bland, L C; Bordyuzhin, I G; Borowski, W; Bouchet, J; Brandin, A V; Brovko, S G; Bültmann, S; Bunzarov, I; Burton, T P; Butterworth, J; Caines, H; Calderón de la Barca Sánchez, M; Campbell, J M; Cebra, D; Cendejas, R; Cervantes, M C; Chaloupka, P; Chang, Z; Chattopadhyay, S; Chen, H F; Chen, J H; Chen, L; Cheng, J; Cherney, M; Chikanian, A; Christie, W; Chwastowski, J; Codrington, M J M; Contin, G; Cramer, J G; Crawford, H J; Cui, X; Das, S; Davila Leyva, A; De Silva, L C; Debbe, R R; Dedovich, T G; Deng, J; Derevschikov, A A; Derradi de Souza, R; Dhamija, S; di Ruzza, B; Didenko, L; Dilks, C; Ding, F; Djawotho, P; Dong, X; Drachenberg, J L; Draper, J E; Du, C M; Dunkelberger, L E; Dunlop, J C; Efimov, L G; Engelage, J; Engle, K S; Eppley, G; Eun, L; Evdokimov, O; Eyser, O; Fatemi, R; Fazio, S; Fedorisin, J; Filip, P; Finch, E; Fisyak, Y; Flores, C E; Gagliardi, C A; Gangadharan, D R; Garand, D; Geurts, F; Gibson, A; Girard, M; Gliske, S; Greiner, L; Grosnick, D; Gunarathne, D S; Guo, Y; Gupta, A; Gupta, S; Guryn, W; Haag, B; Hamed, A; Han, L-X; Haque, R; Harris, J W; Heppelmann, S; Hirsch, A; Hoffmann, G W; Hofman, D J; Horvat, S; Huang, B; Huang, H Z; Huang, X; Huck, P; Humanic, T J; Igo, G; Jacobs, W W; Jang, H; Judd, E G; Kabana, S; Kalinkin, D; Kang, K; Kauder, K; Ke, H W; Keane, D; Kechechyan, A; Kesich, A; Khan, Z H; Kikola, D P; Kisel, I; Kisiel, A; Koetke, D D; Kollegger, T; Konzer, J; Koralt, I; Kosarzewski, L K; Kotchenda, L; Kraishan, A F; Kravtsov, P; Krueger, K; Kulakov, I; Kumar, L; Kycia, R A; Lamont, M A C; Landgraf, J M; Landry, K D; Lauret, J; Lebedev, A; Lednicky, R; Lee, J H; LeVine, M J; Li, C; Li, W; Li, X; Li, X; Li, Y; Li, Z M; Lisa, M A; Liu, F; Ljubicic, T; Llope, W J; Lomnitz, M; Longacre, R S; Luo, X; Ma, G L; Ma, Y G; Madagodagettige Don, D M M D; Mahapatra, D P; Majka, R; Margetis, S; Markert, C; Masui, H; Matis, H S; McDonald, D; McShane, T S; Minaev, N G; Mioduszewski, S; Mohanty, B; Mondal, M M; Morozov, D A; Mustafa, M K; Nandi, B K; Nasim, Md; Nayak, T K; Nelson, J M; Nigmatkulov, G; Nogach, L V; Noh, S Y; Novak, J; Nurushev, S B; Odyniec, G; Ogawa, A; Oh, K; Ohlson, A; Okorokov, V; Oldag, E W; Olvitt, D L; Pachr, M; Page, B S; Pal, S K; Pan, Y X; Pandit, Y; Panebratsev, Y; Pawlak, T; Pawlik, B; Pei, H; Perkins, C; Peryt, W; Pile, P; Planinic, M; Pluta, J; Poljak, N; Poniatowska, K; Porter, J; Poskanzer, A M; Pruthi, N K; Przybycien, M; Pujahari, P R; Putschke, J; Qiu, H; Quintero, A; Ramachandran, S; Raniwala, R; Raniwala, S; Ray, R L; Riley, C K; Ritter, H G; Roberts, J B; Rogachevskiy, O V; Romero, J L; Ross, J F; Roy, A; Ruan, L; Rusnak, J; Rusnakova, O; Sahoo, N R; Sahu, P K; Sakrejda, I; Salur, S; Sandweiss, J; Sangaline, E; Sarkar, A; Schambach, J; Scharenberg, R P; Schmah, A M; Schmidke, W B; Schmitz, N; Seger, J; Seyboth, P; Shah, N; Shahaliev, E; Shanmuganathan, P V; Shao, M; Sharma, B; Shen, W Q; Shi, S S; Shou, Q Y; Sichtermann, E P; Singaraju, R N; Skoby, M J; Smirnov, D; Smirnov, N; Solanki, D; Sorensen, P; Spinka, H M; Srivastava, B; Stanislaus, T D S; Stevens, J R; Stock, R; Strikhanov, M; Stringfellow, B; Sumbera, M; Sun, X; Sun, X M; Sun, Y; Sun, Z; Surrow, B; Svirida, D N; Symons, T J M; Szelezniak, M A; Takahashi, J; Tang, A H; Tang, Z; Tarnowsky, T; Thomas, J H; Timmins, A R; Tlusty, D; Tokarev, M; Trentalange, S; Tribble, R E; Tribedy, P; Trzeciak, B A; Tsai, O D; Turnau, J; Ullrich, T; Underwood, D G; Van Buren, G; van Nieuwenhuizen, G; Vandenbroucke, M; Vanfossen, J A; Varma, R; Vasconcelos, G M S; Vasiliev, A N; Vertesi, R; Videbæk, F; Viyogi, Y P; Vokal, S; Vossen, A; Wada, M; Wang, F; Wang, G; Wang, H; Wang, J S; Wang, X L; Wang, Y; Wang, Y; Webb, G; Webb, J C; Westfall, G D; Wieman, H; Wissink, S W; Witt, R; Wu, Y F; Xiao, Z; Xie, W; Xin, K; Xu, H; Xu, J; Xu, N; Xu, Q H; Xu, Y; Xu, Z; Yan, W; Yang, C; Yang, Y; Yang, Y; Ye, Z; Yepes, P; Yi, L; Yip, K; Yoo, I-K; Yu, N; Zawisza, Y; Zbroszczyk, H; Zha, W; Zhang, J B; Zhang, J L; Zhang, S; Zhang, X P; Zhang, Y; Zhang, Z P; Zhao, F; Zhao, J; Zhong, C; Zhu, X; Zhu, Y H; Zoulkarneeva, Y; Zyzak, M

    2014-08-15

    We report measurements of single- and double-spin asymmetries for W^{±} and Z/γ^{*} boson production in longitudinally polarized p+p collisions at sqrt[s]=510  GeV by the STAR experiment at RHIC. The asymmetries for W^{±} were measured as a function of the decay lepton pseudorapidity, which provides a theoretically clean probe of the proton's polarized quark distributions at the scale of the W mass. The results are compared to theoretical predictions, constrained by polarized deep inelastic scattering measurements, and show a preference for a sizable, positive up antiquark polarization in the range 0.05

  3. Measurement of Longitudinal Spin Asymmetries for Weak Boson Production in Polarized Proton-Proton Collisions at RHIC

    NASA Astrophysics Data System (ADS)

    Adamczyk, L.; Adkins, J. K.; Agakishiev, G.; Aggarwal, M. M.; Ahammed, Z.; Alekseev, I.; Alford, J.; Anson, C. D.; Aparin, A.; Arkhipkin, D.; Aschenauer, E. C.; Averichev, G. S.; Balewski, J.; Banerjee, A.; Beavis, D. R.; Bellwied, R.; Bhasin, A.; Bhati, A. K.; Bhattarai, P.; Bichsel, H.; Bielcik, J.; Bielcikova, J.; Bland, L. C.; Bordyuzhin, I. G.; Borowski, W.; Bouchet, J.; Brandin, A. V.; Brovko, S. G.; Bültmann, S.; Bunzarov, I.; Burton, T. P.; Butterworth, J.; Caines, H.; Calderón de la Barca Sánchez, M.; Campbell, J. M.; Cebra, D.; Cendejas, R.; Cervantes, M. C.; Chaloupka, P.; Chang, Z.; Chattopadhyay, S.; Chen, H. F.; Chen, J. H.; Chen, L.; Cheng, J.; Cherney, M.; Chikanian, A.; Christie, W.; Chwastowski, J.; Codrington, M. J. M.; Contin, G.; Cramer, J. G.; Crawford, H. J.; Cui, X.; Das, S.; Davila Leyva, A.; De Silva, L. C.; Debbe, R. R.; Dedovich, T. G.; Deng, J.; Derevschikov, A. A.; Derradi de Souza, R.; Dhamija, S.; di Ruzza, B.; Didenko, L.; Dilks, C.; Ding, F.; Djawotho, P.; Dong, X.; Drachenberg, J. L.; Draper, J. E.; Du, C. M.; Dunkelberger, L. E.; Dunlop, J. C.; Efimov, L. G.; Engelage, J.; Engle, K. S.; Eppley, G.; Eun, L.; Evdokimov, O.; Eyser, O.; Fatemi, R.; Fazio, S.; Fedorisin, J.; Filip, P.; Finch, E.; Fisyak, Y.; Flores, C. E.; Gagliardi, C. A.; Gangadharan, D. R.; Garand, D.; Geurts, F.; Gibson, A.; Girard, M.; Gliske, S.; Greiner, L.; Grosnick, D.; Gunarathne, D. S.; Guo, Y.; Gupta, A.; Gupta, S.; Guryn, W.; Haag, B.; Hamed, A.; Han, L.-X.; Haque, R.; Harris, J. W.; Heppelmann, S.; Hirsch, A.; Hoffmann, G. W.; Hofman, D. J.; Horvat, S.; Huang, B.; Huang, H. Z.; Huang, X.; Huck, P.; Humanic, T. J.; Igo, G.; Jacobs, W. W.; Jang, H.; Judd, E. G.; Kabana, S.; Kalinkin, D.; Kang, K.; Kauder, K.; Ke, H. W.; Keane, D.; Kechechyan, A.; Kesich, A.; Khan, Z. H.; Kikola, D. P.; Kisel, I.; Kisiel, A.; Koetke, D. D.; Kollegger, T.; Konzer, J.; Koralt, I.; Kosarzewski, L. K.; Kotchenda, L.; Kraishan, A. F.; Kravtsov, P.; Krueger, K.; Kulakov, I.; Kumar, L.; Kycia, R. A.; Lamont, M. A. C.; Landgraf, J. M.; Landry, K. D.; Lauret, J.; Lebedev, A.; Lednicky, R.; Lee, J. H.; LeVine, M. J.; Li, C.; Li, W.; Li, X.; Li, X.; Li, Y.; Li, Z. M.; Lisa, M. A.; Liu, F.; Ljubicic, T.; Llope, W. J.; Lomnitz, M.; Longacre, R. S.; Luo, X.; Ma, G. L.; Ma, Y. G.; Madagodagettige Don, D. M. M. D.; Mahapatra, D. P.; Majka, R.; Margetis, S.; Markert, C.; Masui, H.; Matis, H. S.; McDonald, D.; McShane, T. S.; Minaev, N. G.; Mioduszewski, S.; Mohanty, B.; Mondal, M. M.; Morozov, D. A.; Mustafa, M. K.; Nandi, B. K.; Nasim, Md.; Nayak, T. K.; Nelson, J. M.; Nigmatkulov, G.; Nogach, L. V.; Noh, S. Y.; Novak, J.; Nurushev, S. B.; Odyniec, G.; Ogawa, A.; Oh, K.; Ohlson, A.; Okorokov, V.; Oldag, E. W.; Olvitt, D. L.; Pachr, M.; Page, B. S.; Pal, S. K.; Pan, Y. X.; Pandit, Y.; Panebratsev, Y.; Pawlak, T.; Pawlik, B.; Pei, H.; Perkins, C.; Peryt, W.; Pile, P.; Planinic, M.; Pluta, J.; Poljak, N.; Poniatowska, K.; Porter, J.; Poskanzer, A. M.; Pruthi, N. K.; Przybycien, M.; Pujahari, P. R.; Putschke, J.; Qiu, H.; Quintero, A.; Ramachandran, S.; Raniwala, R.; Raniwala, S.; Ray, R. L.; Riley, C. K.; Ritter, H. G.; Roberts, J. B.; Rogachevskiy, O. V.; Romero, J. L.; Ross, J. F.; Roy, A.; Ruan, L.; Rusnak, J.; Rusnakova, O.; Sahoo, N. R.; Sahu, P. K.; Sakrejda, I.; Salur, S.; Sandweiss, J.; Sangaline, E.; Sarkar, A.; Schambach, J.; Scharenberg, R. P.; Schmah, A. M.; Schmidke, W. B.; Schmitz, N.; Seger, J.; Seyboth, P.; Shah, N.; Shahaliev, E.; Shanmuganathan, P. V.; Shao, M.; Sharma, B.; Shen, W. Q.; Shi, S. S.; Shou, Q. Y.; Sichtermann, E. P.; Singaraju, R. N.; Skoby, M. J.; Smirnov, D.; Smirnov, N.; Solanki, D.; Sorensen, P.; Spinka, H. M.; Srivastava, B.; Stanislaus, T. D. S.; Stevens, J. R.; Stock, R.; Strikhanov, M.; Stringfellow, B.; Sumbera, M.; Sun, X.; Sun, X. M.; Sun, Y.; Sun, Z.; Surrow, B.; Svirida, D. N.; Symons, T. J. M.; Szelezniak, M. A.; Takahashi, J.; Tang, A. H.; Tang, Z.; Tarnowsky, T.; Thomas, J. H.; Timmins, A. R.; Tlusty, D.; Tokarev, M.; Trentalange, S.; Tribble, R. E.; Tribedy, P.; Trzeciak, B. A.; Tsai, O. D.; Turnau, J.; Ullrich, T.; Underwood, D. G.; Van Buren, G.; van Nieuwenhuizen, G.; Vandenbroucke, M.; Vanfossen, J. A.; Varma, R.; Vasconcelos, G. M. S.; Vasiliev, A. N.; Vertesi, R.; Videbæk, F.; Viyogi, Y. P.; Vokal, S.; Vossen, A.; Wada, M.; Wang, F.; Wang, G.; Wang, H.; Wang, J. S.; Wang, X. L.; Wang, Y.; Wang, Y.; Webb, G.; Webb, J. C.; Westfall, G. D.; Wieman, H.; Wissink, S. W.; Witt, R.; Wu, Y. F.; Xiao, Z.; Xie, W.; Xin, K.; Xu, H.; Xu, J.; Xu, N.; Xu, Q. H.; Xu, Y.; Xu, Z.; Yan, W.; Yang, C.; Yang, Y.; Yang, Y.; Ye, Z.; Yepes, P.; Yi, L.; Yip, K.; Yoo, I.-K.; Yu, N.; Zawisza, Y.; Zbroszczyk, H.; Zha, W.; Zhang, J. B.; Zhang, J. L.; Zhang, S.; Zhang, X. P.; Zhang, Y.; Zhang, Z. P.; Zhao, F.; Zhao, J.; Zhong, C.; Zhu, X.; Zhu, Y. H.; Zoulkarneeva, Y.; Zyzak, M.; STAR Collaboration

    2014-08-01

    We report measurements of single- and double-spin asymmetries for W± and Z/γ* boson production in longitudinally polarized p+p collisions at √s =510 GeV by the STAR experiment at RHIC. The asymmetries for W± were measured as a function of the decay lepton pseudorapidity, which provides a theoretically clean probe of the proton's polarized quark distributions at the scale of the W mass. The results are compared to theoretical predictions, constrained by polarized deep inelastic scattering measurements, and show a preference for a sizable, positive up antiquark polarization in the range 0.05

  4. Measurable benefits on brain activity from the practice of educational leisure.

    PubMed

    Requena, Carmen; López, Verónica

    2014-01-01

    Even if behavioral studies relate leisure practices to the preservation of memory in old persons, there is unsubstantial evidence of the import of leisure on brain activity. This study was to compare the brain activity of elderly retired people who engage in different types of leisure activities. Quasi-experimental study over a sample of 60 elderly, retired subjects distributed into three groups according to the leisure activities they practised: educational leisure (G1), memory games (G2), and card games (G3). Applied measures include the conceptual distinction between free time and leisure, the test of the organization of free time measuring 24 clock divisions, and EEG register during 12 word list memorizing. The results show that the type of leisure activity is associated with significant quantitative differences regarding the use of free time. G1 devotes more time to leisure activities than G2 (p = 0.007) and G3 (p = 0.034). G1 rests more actively than the other two groups (p = 0.001). The electrical localization of brain activity indicated a reverse tendency of activation according to the bands and groups. Engaging in educational leisure activities is a useful practice to protect healthy brain compensation strategies. Future longitudinal research may verify the causal relation between practicing educational leisure activities and functional brain aging.

  5. Practice patterns of ophthalmologists administering intravitreal injections in Europe: a longitudinal survey

    PubMed Central

    Huang, Kui; Sultan, Marla B; Zhou, Duo; Tressler, Charles S; Mo, Jingping

    2016-01-01

    Purpose This study was performed to understand the practice patterns of ophthalmologists administering intravitreal (IVT) injections in Europe after the procedure became routine. Methods As part of a prospective, multinational, non-interventional cohort study in 13 countries in Europe between 2006 and 2012, ophthalmologists completed the Baseline Questionnaire and the Follow-up Questionnaire 1 year after baseline. Results and discussion Of the 125 ophthalmologists who participated in the study, 113 (90.4%) completed the Baseline Questionnaire. Most of these ophthalmologists were medical retina specialists (43.0%). The median number of IVT injections that the ophthalmologists performed per month during the year prior to completing the Baseline Questionnaire was 20.0. The majority of the ophthalmologists had performed their last IVT injection prior to completing the questionnaire in an operating room or theater (68.4%). When performing IVT injections, a majority of the ophthalmologists reported applying povidone–iodine (90.4%) before IVT injections and topical antibiotics right after IVT injections (89.5%). In addition, 81.6% of the ophthalmologists reported using a sterile adhesive eye drape and 80.7% reported using an eyelid speculum. In all, 95 ophthalmologists (76%) completed the Follow-up Questionnaire. The median number of IVT injections performed per month during the year prior to completing the Follow-up Questionnaire by these ophthalmologists was increased to 35. The results of the Follow-up Questionnaire on administering IVT injections were similar to those of the Baseline Questionnaire. A majority of the ophthalmologists reported applying povidone–iodine (87.4%) before IVT injections, topical antibiotics right after IVT injections (89.5%), and an eyelid speculum (85.3%). Conclusion The results of this study indicated a good adherence to all aspects of the guidelines on IVT injections. It seemed that ophthalmologists were more experienced in IVT

  6. Longitudinal design for sonographic measurement of median nerve swelling with controlled exposure to physical work using an animal model.

    PubMed

    Roll, Shawn C; Evans, Kevin D; Volz, Kevin R; Sommerich, Carolyn M

    2013-12-01

    In the study described here, we examined the feasibility of a longitudinal design to measure sonographically swelling of the median nerve caused by controlled exposure to a work task and to evaluate the relationship of changes in morphology to diagnostic standards. Fifteen macaques, Macaca fascicularis, pinched a lever in various wrist positions at a self-regulated pace (8 h/d, 5 d/wk, 18-20 wk). Nerve conduction velocity (NCV) and cross-sectional area (CSA) were measured every 2 wk from baseline through working and a 6-wk recovery. Trending across all subjects revealed that NCV slowed and CSA at the carpal tunnel increased in the working arm, whereas no changes were observed in CSA either at the forearm or for any measure in the non-working arm. There was a small negative correlation between NCV and CSA in the working arm. This study provides validation that swelling can be observed using a longitudinal design. Longitudinal human studies are needed to describe the trajectory of nerve swelling for early identification of median nerve pathology. Copyright © 2013 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  7. Constructing a Measure for Longitudinal Medical Achievement Studies by the Rasch Model One-Step Equating.

    ERIC Educational Resources Information Center

    Shen, Linjun

    As part of a longitudinal study of the growth of general medical knowledge among osteopathic medical students, a simple, convenient, and accurate vertical equating method was developed for constructing a scale for medical achievement. It was believed that Parts 1, 2, and 3 of the National Board of Osteopathic Medical Examiners' (NBOME) examination…

  8. Emotional Intelligence throughout Portuguese Secondary School: A Longitudinal Study Comparing Performance and Self-Report Measures

    ERIC Educational Resources Information Center

    Costa, Ana; Faria, Luísa

    2016-01-01

    This study examines the developmental trajectories of ability and trait emotional intelligence (EI) in the Portuguese secondary school. Within a three-wave longitudinal design, 395 students (M[subscript age] = 15.4; SD = 0.74) completed both the Emotional Skills and Competence Questionnaire (ESCQ) and the Vocabulary of Emotions Test (VET). Results…

  9. Measuring Growth in a Longitudinal Large-Scale Assessment with a General Latent Variable Model

    ERIC Educational Resources Information Center

    von Davier, Matthias; Xu, Xueli; Carstensen, Claus H.

    2011-01-01

    The aim of the research presented here is the use of extensions of longitudinal item response theory (IRT) models in the analysis and comparison of group-specific growth in large-scale assessments of educational outcomes. A general discrete latent variable model was used to specify and compare two types of multidimensional item-response-theory…

  10. Parental Contributions to Longitudinal Stability of Cognitive Measures in the Colorado Family Reading Study.

    ERIC Educational Resources Information Center

    DeFries, J. C.; Baker, Laura A.

    1983-01-01

    Data on reading-disabled and control probands (pairs matched for sex, age, and school district) and their families were subjected to a comprehensive longitudinal-familial path analysis. Covariance matrices were constructed from composite scores for reading performance and for coding and symbol processing speed, and maximum likelihood estimates of…

  11. Longitudinal Assessment of Student Learning: Simplistic Measures Aren't Enough

    ERIC Educational Resources Information Center

    Beyer, Catharine Hoffman; Gillmore, Gerald M.

    2007-01-01

    In an attempt to capture the diverse experience of undergraduates at the University of Washington (UW), the authors designed and conducted the University of Washington's Study of Undergraduate Learning (UW SOUL), a longitudinal study that tracked 304 students (about five percent of the entering freshman and transfer class) through their…

  12. Emotional Intelligence throughout Portuguese Secondary School: A Longitudinal Study Comparing Performance and Self-Report Measures

    ERIC Educational Resources Information Center

    Costa, Ana; Faria, Luísa

    2016-01-01

    This study examines the developmental trajectories of ability and trait emotional intelligence (EI) in the Portuguese secondary school. Within a three-wave longitudinal design, 395 students (M[subscript age] = 15.4; SD = 0.74) completed both the Emotional Skills and Competence Questionnaire (ESCQ) and the Vocabulary of Emotions Test (VET). Results…

  13. Longitudinal NMR parameter measurements of Japanese pear fruit during the growing process using a mobile magnetic resonance imaging system

    NASA Astrophysics Data System (ADS)

    Geya, Yuto; Kimura, Takeshi; Fujisaki, Hirotaka; Terada, Yasuhiko; Kose, Katsumi; Haishi, Tomoyuki; Gemma, Hiroshi; Sekozawa, Yoshihiko

    2013-01-01

    Longitudinal nuclear magnetic resonance (NMR) parameter measurements of Japanese pear fruit (Pyrus pyrifolia Nakai, Kosui) were performed using an electrically mobile magnetic resonance imaging (MRI) system with a 0.2 T and 16 cm gap permanent magnet. To measure the relaxation times and apparent diffusion coefficients of the pear fruit in relation to their weight, seven pear fruits were harvested almost every week during the cell enlargement period and measured in a research orchard. To evaluate the in situ relaxation times, six pear fruits were longitudinally measured for about two months during the same period. The measurements for the harvested samples showed good agreement with the in situ measurements. From the measurements of the harvested samples, it is clear that the relaxation rates of the pear fruits linearly change with the inverse of the linear dimension of the fruits, demonstrating that the relaxation mechanism is a surface relaxation. We therefore conclude that the mobile MRI system is a useful device for measuring the NMR parameters of outdoor living plants.

  14. Assessing the Practical Equivalence of Conversions when Measurement Conditions Change

    ERIC Educational Resources Information Center

    Liu, Jinghua; Dorans, Neil J.

    2012-01-01

    At times, the same set of test questions is administered under different measurement conditions that might affect the psychometric properties of the test scores enough to warrant different score conversions for the different conditions. We propose a procedure for assessing the practical equivalence of conversions developed for the same set of test…

  15. 38 CFR 21.4275 - Practical training courses; measurement.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 2 2011-07-01 2011-07-01 false Practical training courses; measurement. 21.4275 Section 21.4275 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS (CONTINUED) VOCATIONAL REHABILITATION AND EDUCATION Administration of Educational...

  16. Measuring Attitudes toward Acceptable and Unacceptable Parenting Practices

    ERIC Educational Resources Information Center

    Budd, Karen S.; Behling, Steven; Li, Yan; Parikshak, Sangeeta; Gershenson, Rachel A.; Feuer, Rachel; Danko, Christina M.

    2012-01-01

    This study investigated the properties of a new rating instrument, the Parenting Questionnaire (PQ), designed to measure attitudes about acceptable and unacceptable parenting practices. In Study 1, subject matter experts representing culturally diverse psychologists, parents, and college students were consulted to identify 110 items receiving high…

  17. Procedural Fidelity: An Analysis of Measurement and Reporting Practices

    ERIC Educational Resources Information Center

    Ledford, Jennifer R.; Wolery, Mark

    2013-01-01

    A systematic analysis was conducted of measurement and reporting practices related to procedural fidelity in single-case research for the past 30 years. Previous reviews of fidelity primarily reported whether fidelity data were collected by authors; these reviews reported that collection was variable, but low across journals and over time. Results…

  18. Procedural Fidelity: An Analysis of Measurement and Reporting Practices

    ERIC Educational Resources Information Center

    Ledford, Jennifer R.; Wolery, Mark

    2013-01-01

    A systematic analysis was conducted of measurement and reporting practices related to procedural fidelity in single-case research for the past 30 years. Previous reviews of fidelity primarily reported whether fidelity data were collected by authors; these reviews reported that collection was variable, but low across journals and over time. Results…

  19. Measures of Rheumatoid Arthritis Disease Activity in Australian Clinical Practice

    PubMed Central

    Taylor, Andrew; Bagga, Hanish

    2011-01-01

    Objectives. To investigate which rheumatoid arthritis (RA) disease activity measures are being collected in patients receiving glucocorticoids, non-biologic or biologic disease-modifying antirheumatic drugs (DMARDs) in Australian rheumatology practice. Methods. A retrospective audit of medical records was conducted from eight rheumatology practices around Australia. Each rheumatologist recruited 30 consecutive eligible patients into the review, 10 of whom must have been receiving a biological agent for rheumatoid arthritis. Disease activity measures and radiographic assessments were collected from each patient's last consultation. For biologic patients, disease activity measures were also collected from when the patient was first initiated on the biological agent. Results. At last consultation, the disease measures that were recorded most often were ESR (89.2%), haemoglobin (87.5%), and CRP (84.2%). DAS28 was infrequently recorded (16.3%). The rate of recording disease activity measures for patients receiving biologic DMARDs decreased over time (mean 27 months). Conclusion. This review has shown inconsistency of RA activity measures being recorded in Australian rheumatology clinical practice. An accurate assessment of the disease process is necessary to effectively target rheumatoid arthritis patients to treat in order to achieve optimal outcomes. PMID:22389794

  20. Beyond repeated-measures analysis of variance: advanced statistical methods for the analysis of longitudinal data in anesthesia research.

    PubMed

    Ma, Yan; Mazumdar, Madhu; Memtsoudis, Stavros G

    2012-01-01

    Research in the field of anesthesiology relies heavily on longitudinal designs for answering questions about long-term efficacy and safety of various anesthetic and pain regimens. Yet, anesthesiology research is lagging in the use of advanced statistical methods for analyzing longitudinal data. The goal of this article was to increase awareness of the advantages of modern statistical methods and promote their use in anesthesia research. Here we introduce 2 modern and advanced statistical methods for analyzing longitudinal data: the generalized estimating equations (GEE) and mixed-effects models (MEM). These methods were compared with the conventional repeated-measures analysis of variance (RM-ANOVA) through a clinical example with 2 types of end points (continuous and binary). In addition, we compared GEE and MEM to RM-ANOVA through a simulation study with varying sample sizes, varying number of repeated measures, and scenarios with and without missing data. In the clinical study, the 3 methods are found to be similar in terms of statistical estimation, whereas the parameter interpretations are somewhat different. The simulation study shows that the methods of GEE and MEM are more efficient in that they are able to achieve higher power with smaller sample size or lower number of repeated measurements in both complete and missing data scenarios. Based on their advantages over RM-ANOVA, GEE and MEM should be strongly considered for the analysis of longitudinal data. In particular, GEE should be used to explore overall average effects, and MEM should be used when subject-specific effects (in addition to overall average effects) are of primary interest.

  1. A longitudinal study of hallux valgus surgical outcomes using a validated patient centred outcome measure.

    PubMed

    Spruce, Michelle C; Bowling, Frank L; Metcalfe, Stuart A

    2011-09-01

    Hallux valgus is a common chronic condition affecting up to a third of the population. Progressive disruption to the complex anatomy of the first ray involving metatarsal, sesamoids and hallux impose both structural and functional alteration to the foot which underpin the secondary pathologies associated with this condition. It is common for patients to seek correction of the deformity in order to alleviate pain and improve footwear tolerance. Surgical intervention remains the only viable means to restore osseous alignments. To date there remains no universally accepted standards for procedure selection. A total of 179 consecutive participants were recruited into the study. Ethical approval was obtained and all participants consented to participate in the study, in accordance with the Helsinki Declaration. All patients attending the Department of Podiatric Surgery, between July 2004 and October 2007 for the surgical management of hallux valgus were invited to complete a Foot Health Status Questionnaire. Pre-operative data collection on all participants was undertaken on the day of admission, using the validated Foot Health Status Questionnaire measurement tool as with previous studies. A total of 179 complete data sets were recorded in this longitudinal study with an average participant age of 49.4 years (SD 14.5). The group comprised 164 females and 15 males. The mean days for administration of the Foot Health Status Questionnaire post operative follow up was 1045 days (149 weeks or 2.9 years). The results demonstrated that within all four foot specific domains, the minimal important differences were achieved by the majority of the group. Meanwhile, in domains relating to general health, physical activity, vigour and social capacity, the majority of participants failed to attain the calculated minimal important difference (94 [53%], 96 [54%], 93 [52%], 93 [52%], respectively). The authors have presented for the first time minimal important difference for all eight

  2. Experimental Measurements of Longitudinal and Transverse Dispersion in Miscible Fluids with a High Viscosity and Density Contrast

    NASA Astrophysics Data System (ADS)

    Alkindi, A.; Bijeljic, B.; Muggeridge, A.

    2008-12-01

    Diffusion and advective dispersion may have a significant influence on the mixing between miscible fluids during displacement processes in porous media. This is particularly important when intimate mixing may result in important changes to the fluid behaviour. For example in oil recovery, mixing between injected and connate water will tend to reduce the efficiency of low salinity water injection. On the other hand recovery may be increased if injected gas mixes with high viscosity oil increasing its mobility. Most experimental data for longitudinal and transverse dispersion have been obtained using fluid pairs with very similar viscosities and densities. The traditional description (Perkins and Johnston, 1963) suggests that longitudinal dispersion decreases as mobility ratio increases. It also suggests that gravity will tend to reduce transverse dispersion. We provide experimental measurements of longitudinal (KL) and transverse (KT) dispersion at low Reynolds number as a function of Peclet number for the first contact miscible ethanol- glycerol fluid system flowing in a porous media formed from glass beads. These fluids have a high viscosity ratio of over 1000 and a significant density difference of 470 kg m-3. We show that both KL and KT are similar to values measured for a water-brine system but that KT is reduced when the less dense ethanol is flowing above the denser glycerol.

  3. Longitudinal design for sonographic measurement of median nerve swelling with controlled exposure to physical work using an animal model

    PubMed Central

    Roll, Shawn C.; Evans, Kevin D.; Volz, Kevin R.; Sommerich, Carolyn M.

    2013-01-01

    This study examined the feasibility of a longitudinal design to sonographically measure swelling of the median nerve due to controlled exposure to a work task and to evaluate the relationship of changes in morphology to diagnostic standards. Fifteen macaca fascicularis pinched a lever in various wrist positions at a self-regulated pace (8 hours/day, 5 days/week, 18–20 weeks). Nerve conduction velocity (NCV) and cross-sectional area (CSA) were obtained every two weeks from baseline through working and a 6-week recovery. Trending across all subjects showed that NCV slowed and CSA at the carpal tunnel increased in the working arm, while no changes were observed in CSA either at the forearm or for any measure in the non-working arm. There was a small negative correlation between NCV and CSA in the working arm. This study provides validation that swelling can be observed using a longitudinal design. Longitudinal human studies are needed to describe the trajectory of nerve swelling for early identification of median nerve pathology. PMID:24139197

  4. Variable Selection and Inference Procedures for Marginal Analysis of Longitudinal Data with Missing Observations and Covariate Measurement Error

    PubMed Central

    Yi, Grace Y.; Tan, Xianming; Li, Runze

    2015-01-01

    Summary In contrast to extensive attention on model selection for univariate data, research on model selection for longitudinal data remains largely unexplored. This is particularly the case when data are subject to missingness and measurement error. To address this important problem, we propose marginal methods that simultaneously carry out model selection and estimation for longitudinal data with missing responses and error-prone covariates. Our method have several appealing features: the applicability is broad because the methods are developed for a unified framework with marginal generalized linear models; model assumptions are minimal in that no full distribution is required for the response process and the distribution of the mismeasured covariates is left unspecified; and the implementation is straightforward. To justify the proposed methods, we provide both theoretical properties and numerical assessments. PMID:26877582

  5. Efficient use of longitudinal CD4 counts and viral load measures in survival analysis.

    PubMed

    Holte, S E; Randolph, T W; Ding, J; Tien, J; McClelland, R S; Baeten, J M; Overbaugh, J

    2012-08-30

    CD4 counts and viral loads are dynamic quantities that change with time in HIV-infected persons. Commonly used single summary measures, such as viral load set point or early CD4 count, do not explicitly account for changes in viral load or CD4 counts or other features of the overall time course of these measures. However, the efficient use of all repeated measurements within each subject is often a challenge made more difficult by sparse and irregular sampling over time. Here, we illustrate how functional principal component (FPC) analysis provides an effective statistical approach for exploiting the patterns in CD4 count and viral load data over time. We demonstrate the method by using data from Kenyan women who acquired HIV-1 during follow-up in a cohort that practices high-risk activities and were subsequently followed up prospectively from early infection. The FPC scores for each woman obtained using this method served as informative summary statistics for the CD4 count and viral load trajectories. Similar to baseline CD4 count or viral set point, the first FPC score can be interpreted as a single-value summary measure of an individual's overall CD4 count or viral load. However, unlike most single-value summaries of CD4 count or viral load trajectories, the first FPC score summarizes the dynamics of these quantities and is seen to reveal specific features of the trajectories associated with mortality in this cohort. Moreover, the FPC scores are shown to be a more powerful prognostic factor than other common summaries when used in survival analysis. Copyright © 2012 John Wiley & Sons, Ltd.

  6. Best Practices for Measuring Students’ Attitudes toward Learning Science

    PubMed Central

    Lovelace, Matthew; Brickman, Peggy

    2013-01-01

    Science educators often characterize the degree to which tests measure different facets of college students’ learning, such as knowing, applying, and problem solving. A casual survey of scholarship of teaching and learning research studies reveals that many educators also measure how students’ attitudes influence their learning. Students’ science attitudes refer to their positive or negative feelings and predispositions to learn science. Science educators use attitude measures, in conjunction with learning measures, to inform the conclusions they draw about the efficacy of their instructional interventions. The measurement of students’ attitudes poses similar but distinct challenges as compared with measurement of learning, such as determining validity and reliability of instruments and selecting appropriate methods for conducting statistical analyses. In this review, we will describe techniques commonly used to quantify students’ attitudes toward science. We will also discuss best practices for the analysis and interpretation of attitude data. PMID:24297288

  7. Best practices for measuring students' attitudes toward learning science.

    PubMed

    Lovelace, Matthew; Brickman, Peggy

    2013-01-01

    Science educators often characterize the degree to which tests measure different facets of college students' learning, such as knowing, applying, and problem solving. A casual survey of scholarship of teaching and learning research studies reveals that many educators also measure how students' attitudes influence their learning. Students' science attitudes refer to their positive or negative feelings and predispositions to learn science. Science educators use attitude measures, in conjunction with learning measures, to inform the conclusions they draw about the efficacy of their instructional interventions. The measurement of students' attitudes poses similar but distinct challenges as compared with measurement of learning, such as determining validity and reliability of instruments and selecting appropriate methods for conducting statistical analyses. In this review, we will describe techniques commonly used to quantify students' attitudes toward science. We will also discuss best practices for the analysis and interpretation of attitude data.

  8. Small practices' experience with EHR, quality measurement, and incentives.

    PubMed

    Begum, Rohima; Smith Ryan, Mandy; Winther, Chloe H; Wang, Jason J; Bardach, Naomi S; Parsons, Amanda H; Shih, Sarah C; Dudley, R Adams

    2013-11-01

    To assess clinician attitudes and experiences in Health eHearts, a quality recognition and financial incentive program using health information technology. Survey of physicians. A survey was administered to 140 lead clinicians at each participating practice. Survey domains included clinicians' experiences and attitudes toward the selected clinical quality measures focused on cardiovascular care, use of electronic health records (EHRs), technical assistance visits, quality measurement reports, and incentive payments. Responses were compared across groups of practices receiving financial incentives with those in the control (no financial rewards). Survey response rate was 74%. The majority of respondents reported receiving and reviewing the quality reports (89%), agreed with the prioritization of measures (89%), and understood the information given in the quality reports (95%). Over half of the respondents had a quality improvement visit (56%), with incentive clinicians more likely to have had a visit compared with the control group (68% vs 43%, P = .01). The incentive group respondents (92%) were more likely to report using clinical decision support system alerts than control group respondents (82%, P = .11). Clinicians in both incentive and control groups reported positive experiences with the program. No differences were detected between groups regarding agreement with selected clinical measures or their relevance to the patient population. However, clinicians in the incentive group were more likely to review quarterly performance reports and access quality improvement visits. Incentives may be used to further engage clinicians operating in small independently owned practices to participate in quality improvement activities.

  9. Semi-spontaneous oral text production: measurements in clinical practice.

    PubMed

    Lind, Marianne; Kristoffersen, Kristian Emil; Moen, Inger; Simonsen, Hanne Gram

    2009-12-01

    Functionally relevant assessment of the language production of speakers with aphasia should include assessment of connected speech production. Despite the ecological validity of everyday conversations, more controlled and monological types of texts may be easier to obtain and analyse in clinical practice. This article discusses some simple measurements for the analysis of semi-spontaneous oral text production by speakers with aphasia. Specifically, the measurements are related to the production of verbs and nouns, and the realization of different sentence types. The proposed measurements should be clinically relevant, easily applicable, and linguistically meaningful. The measurements have been applied to oral descriptions of the 'Cookie Theft' picture by eight monolingual Norwegian speakers, four with an anomic type of aphasia and four without any type of language impairment. Despite individual differences in both the clinical and the non-clinical group, most of the measurements seem to distinguish between speakers with and without aphasia.

  10. Longitudinal measurements of total body water and body composition in healthy volunteers by online breath deuterium measurement and other near-subject methods.

    PubMed

    Engel, Barbara; Spanel, Patrik; Smith, David; Diskin, Ann; Davies, Simon J

    2004-01-01

    Rapid quantification of breath deuterium abundance by flowing afterglow mass spectrometry (FA-MS) enables accurate measurement of total body water (TBW), which combined with other techniques such as bioelectrical impedance analysis (BIA) and anthropometrics enables near-subject assessment of body composition. This study assessed the comparative reproducibility and inter-relationship of these methods in healthy subjects over 12 months. Detailed bedside composition was performed in 22 subjects, (10 male) aged 28-79 with body mass index (BMI) ranging from 21-38 at baseline and again at one year. Techniques included FA-MS deuterium dilution, BIA, skin-fold thickness (SFT) and soft tissue ultrasound measurement of fat and muscle depth. Short-term reproducibility for each method was established. Within and between technique comparisons of measurement were made from Pearson's linear regression, coefficient of variation (CV) and Bland-Altman analysis. Weight and TBW estimated by FA-MS, BIA and SFT at baseline and one year later were highly correlated (R(2) = 0.96-0.98), slope 1.02-1.03, CV = 4.5-11.6%. Systematic errors between the different methods in determining TBW were effectively identical at baseline and after one year. There was a tendency for subjects to gain weight during the study period, due to an increase, predominantly in younger women, of body water (FA-MS and SFT) and loss of upper body fat (ultrasound). BIA was relatively insensitive to these changes. It is concluded that over a 12-month period, TBW determined by FA-MS deuterium breath analysis has reproducibility similar to conventional weighing. The stability of between method errors would suggest that these techniques might be used in conjunction with each other in the longitudinal determination of body composition and so detect relatively subtle changes. The value of including an absolute determinant of TBW by FA-MS that is independent of the need to employ population derived equations, appears to be of

  11. Accounting for Posttraumatic Stress Disorder Symptom Severity With Pre- and Posttrauma Measures: A Longitudinal Study of Older Adults

    PubMed Central

    Ogle, Christin M.; Rubin, David C.; Siegler, Ilene C.

    2015-01-01

    Using data from a longitudinal study of community-dwelling older adults, we analyzed the most extensive set of known correlates of PTSD symptoms obtained from a single sample to examine the measures’ independent and combined utility in accounting for PTSD symptom severity. Fifteen measures identified as PTSD risk factors in published meta-analyses and 12 theoretically and empirically supported individual difference and health-related measures were included. Individual difference measures assessed after the trauma, including insecure attachment and factors related to the current trauma memory, such as self-rated severity, event centrality, frequency of involuntary recall, and physical reactions to the memory, accounted for symptom severity better than measures of pre-trauma factors. In an analysis restricted to prospective measures assessed before the trauma, the total variance explained decreased from 56% to 16%. Results support a model of PTSD in which characteristics of the current trauma memory promote the development and maintenance of PTSD symptoms. PMID:27004143

  12. Measurements of the Neutron Longitudinal Spin Asymmetry A1n and Flavor Decomposition in the Valence Quark Region

    SciTech Connect

    Flay, David J.

    2014-08-01

    The current data for the nucleon-virtual photon longitudinal spin asymmetry A1 on the proton and neutron have shown that the ratio of the polarized-to-unpolarized down-quarkparton distribution functions,Dd=d, tends towards -1/2 at large x, in disagreement with the perturbative QCD prediction that Dd/d approaches 1 but more in line with constituent quark models. As a part of experiment E06-014 in Hall A of Jefferson Lab, double-spin asymmetries were measured in the scattering of a longitudinally polarized electron beam of energies 4.74 and 5.89 GeV from a longitudinally and transversely polarized 3He target in the deep inelastic scattering and resonance region, allowing for the extraction of the neutron asymmetry An1 and the ratios Dd/d and Du/u. We will discuss our analysis of the data and present results for A1 and g1/F1 on both 3He and the neutron, and the resulting quark ratios for the up and down quarks in the kinematic range of 0.2

  13. Parenting Practices and Perceived Social Support: Longitudinal Relations with the Social Competence of Mexican-origin Children

    PubMed Central

    Taylor, Zoe E.; Conger, Rand D.; Robins, Richard W.; Widaman, Keith F.

    2015-01-01

    Social bonds and supportive relationships are widely recognized as being indispensable to healthy psychological functioning and well-being. Social support is a psychological resource that is expected to also contribute positively to parenting practices. The present study longitudinally examined the relations between mothers’ (N = 674) and fathers’ (N = 430) perceived social support and parenting behaviors, and their relations with children’s social competence during early adolescence in Mexican-origin single and two-parent families. Our constructs of interest (warm parenting, monitoring, perceived social support, and children’s social competence) were significantly correlated at T1, and demonstrated significant stability across time for both parental models. Parental warmth (as reported by the child, and opposite parent) and parental monitoring (self-reported by mothers and fathers) were correlated and also showed bidirectional associations across time. Parental monitoring at T2 positively predicted change in children’s social competence at T3 (controlling for T1 social competence) for mothers. Parental warmth at T2 positively predicted change in children’s social competence at T3 (controlling for T1 social competence) for fathers. For mothers, the indirect effect of social support at T1 on children’s social competence at T3 via parental monitoring at T2 (and controlling for prior levels) was significant. Findings suggest that maternal perceived social support contributes to children’s social competence due to its positive relation to maternal monitoring. Results may also suggest that mothers’ and fathers’ parenting behaviors differentially relate to children’s social competence in Latino families, although additional work focused on comparing parenting behaviors in two-parent families is needed. PMID:26751039

  14. Parenting Practices and Perceived Social Support: Longitudinal Relations with the Social Competence of Mexican-origin Children.

    PubMed

    Taylor, Zoe E; Conger, Rand D; Robins, Richard W; Widaman, Keith F

    2015-11-01

    Social bonds and supportive relationships are widely recognized as being indispensable to healthy psychological functioning and well-being. Social support is a psychological resource that is expected to also contribute positively to parenting practices. The present study longitudinally examined the relations between mothers' (N = 674) and fathers' (N = 430) perceived social support and parenting behaviors, and their relations with children's social competence during early adolescence in Mexican-origin single and two-parent families. Our constructs of interest (warm parenting, monitoring, perceived social support, and children's social competence) were significantly correlated at T1, and demonstrated significant stability across time for both parental models. Parental warmth (as reported by the child, and opposite parent) and parental monitoring (self-reported by mothers and fathers) were correlated and also showed bidirectional associations across time. Parental monitoring at T2 positively predicted change in children's social competence at T3 (controlling for T1 social competence) for mothers. Parental warmth at T2 positively predicted change in children's social competence at T3 (controlling for T1 social competence) for fathers. For mothers, the indirect effect of social support at T1 on children's social competence at T3 via parental monitoring at T2 (and controlling for prior levels) was significant. Findings suggest that maternal perceived social support contributes to children's social competence due to its positive relation to maternal monitoring. Results may also suggest that mothers' and fathers' parenting behaviors differentially relate to children's social competence in Latino families, although additional work focused on comparing parenting behaviors in two-parent families is needed.

  15. Profiles of and practices in crisis resolution and home treatment teams in Norway: a longitudinal survey study

    PubMed Central

    2011-01-01

    Background Crisis resolution and home treatment (CRHT) is one of the more recent modes of delivering acute mental health care in the community. The objective of the study was to describe the standardizations and variations in the CRHT teams in Norway in order to gain knowledge regarding the structures and processes of CRHT teams. Methods A longitudinal survey of five CRHT teams in Norway was carried out for a period of 18 months with two sets of questionnaires-one for CRHT team profiles for a bi-yearly survey and the other for services and practices of CRHT teams for a monthly survey. Results The five CRHT teams were configured by a set of common basic characteristics in their operations, while at the same time were variant in several areas of the teams' structures and processes. Significant differences among the teams were evident in terms of the structural aspects such as service locality, staffing and team make-up, caseload, service hours, and travel time, and the process aspects such as the number of referrals received, referral source, admission, service duration, and discharge destination. These variations are reflected upon the perspectives regarding the nature of mental health crisis, the conflicting policies in mental health services, and the nature of home-based mental health care. Conclusions The diversity in the way CRHT teams are established and operate needs to be examined further in order to understand the reasons for such variations and their impact on the quality of services to service users and in relation to the total mental health service system in a community. PMID:21878115

  16. When a LIC came to town: the impact of longitudinal integrated clerkships on a rural community of healthcare practice.

    PubMed

    Hudson, Judith N; Thomson, Brett; Weston, Kathryn M; Knight-Billington, Patricia J

    2015-01-01

    Two small rural towns in Australia, where medical practitioners provide primary care to the population, including emergency, anaesthetic and obstetric services, were early adopters of an innovative year-long integrated clerkship (clinical placement) designed to foster medical student skill attainment and a commitment to underserved rural communities. Primary care vocational trainees had previously trained in the region. Engaging with the university to participate in the clerkship initiative for undergraduate medical education offered the local healthcare service an opportunity to really integrate education with service. This study sought perspectives from a multidisciplinary group of stakeholders on the impact of the longitudinal integrated clerkship (LIC) on the healthcare community. Three analysts independently analysed the transcripts arising from semi-structured interviews with a range of health care clinicians and managers (N=23). Themes were identified using inductive content analysis methodology. Four major themes emerged from the perspectives of a multi-professional group of participants from both towns: transforming a community of practice, realising the potential of the health service, investment in rural return, and sustainability. There was significant clinical exposure, skill and teaching capacity in these previously unrecognised rural placements but realising the potential of the health service needs careful management to sustain this resource. Early engagement and initial enthusiasm have produced many positive outcomes for the healthcare community, but this alone is not sufficient to sustain an increasing role for rural primary care in medical education. The study identified issues that need addressing for sustainability, namely validation, time and costs. Strategies to address these are key to continuation of LICs in small rural communities.

  17. Effects of ballet training of children in Turkey on foot anthropometric measurements and medial longitudinal arc development.

    PubMed

    Ozdinc, Sevgi Anar; Turan, Fatma Nesrin

    2016-07-01

    To investigate the effects of ballet training on foot structure and the formation of the medial longitudinal arc in childhood, and the association of body mass index with structural change secondary to ballet training. This study was conducted at Öykü Ballet and Dance School and Trakya University, Edirne, Turkey, from September 2007 to November 2008, and comprised girl students who were taking ballet classes, and a group of those who were not taking such who acted as the controls. Static footprints of both feet of all participants were taken with an ink paedogram. Parameters evaluated from footprints included foot length, metatarsal width, heel width and medial longitudinal arch. The relationship between the parameters, the ballet starting age, training duration and body mass index was investigated. Of the 67 participants, there were 36(53.7%) in the experimental group and 31(48.3%) in the control group. The difference between age, height, weight and body mass index between the two groups was insignificant (p>0.05). The average ballet starting age was 6.47±1.55 years and duration was 4.36±2.002 years. Positive correlations were found between body mass index and foot length, metatarsal width, heel width, medial longitudinal arch contact width and halluxvalgus angle; between ballet starting age and metatarsal width, heel width; between duration of training and foot length, metatarsal width and hallux valgus angle (p?0.05 each). Evidence supporting the education in children on foot anthropometric measurements and medial longitudinal arc development could not be found.

  18. Does a Social Work Degree Predict Practice Orientation? Measuring Strengths-Based Practice among Child Welfare Workers with the Strengths-Based Practices Inventory-Provider Version

    ERIC Educational Resources Information Center

    Douglas, Emily M.; McCarthy, Sean C.; Serino, Patricia A.

    2014-01-01

    Strengths-based practice (SBP) is one of the primary modalities of social work practice. The literature on SBP does not address a standardized tool for measuring SBP or whether receipt of a social work degree is related to practice orientation. We measure SBP with a provider-based Strengths-Based Practices Inventory (SBPI-P) and examine whether a…

  19. Teaching our children when to eat: how parental feeding practices inform the development of emotional eating--a longitudinal experimental design.

    PubMed

    Farrow, Claire V; Haycraft, Emma; Blissett, Jackie M

    2015-05-01

    Emotional eating in children has been related to the consumption of energy-dense foods and obesity, but the development of emotional eating in young children is poorly understood. We evaluated whether emotional eating can be induced in 5-7-y-old children in the laboratory and assessed whether parental use of overly controlling feeding practices at 3-5 y of age predicts a greater subsequent tendency for children to eat under conditions of mild stress at ages 5-7 y. Forty-one parent-child dyads were recruited to participate in this longitudinal study, which involved parents and children being observed consuming a standard lunch, completing questionnaire measures of parental feeding practices, participating in a research procedure to induce child emotion (or a control procedure), and observing children's consumption of snack foods. Children at ages 5-7 y who were exposed to a mild emotional stressor consumed significantly more calories from snack foods in the absence of hunger than did children in a control group. Parents who reported the use of more food as a reward and restriction of food for health reasons with their children at ages 3-5 y were more likely to have children who ate more under conditions of negative emotion at ages 5-7 y. Parents who overly control children's food intake may unintentionally teach children to rely on palatable foods to cope with negative emotions. Additional research is needed to evaluate the implications of these findings for children's food intake and weight outside of the laboratory setting. This trial was registered at clinicaltrials.gov as NCT01122290. © 2015 American Society for Nutrition.

  20. Factorial Validity of the Decisional Involvement Scale as a Measure of Content and Context of Nursing Practice.

    PubMed

    Yurek, Leo A; Havens, Donna S; Hays, Spencer; Hughes, Linda C

    2015-10-01

    Decisional involvement is widely recognized as an essential component of a professional nursing practice environment. In recent years, researchers have added to the conceptualization of nurses' role in decision-making to differentiate between the content and context of nursing practice. Yet, instruments that clearly distinguish between these two dimensions of practice are lacking. The purpose of this study was to examine the factorial validity of the Decisional Involvement Scale (DIS) as a measure of both the content and context of nursing practice. This secondary analysis was conducted using data from a longitudinal action research project to improve the quality of nursing practice and patient care in six hospitals (N = 1,034) in medically underserved counties of Pennsylvania. A cross-sectional analysis of baseline data from the parent study was used to compare the factor structure of two models (one nested within the other) using confirmatory factor analysis. Although a comparison of the two models indicated that the addition of second-order factors for the content and context of nursing practice improved model fit, neither model provided optimal fit to the data. Additional model-generating research is needed to develop the DIS as a valid measure of decisional involvement for both the content and context of nursing practice.

  1. Characteristics of dosemeter types for skin dose measurements in practice.

    PubMed

    Van Dam, J; Bosmans, H; Marchal, G; Wambersie, A

    2005-01-01

    A growing number of papers report deterministic effects in the skin of patients who have undergone interventional radiological procedures. Dose measurements, and especially skin dose measurements, are therefore increasingly important. Methods and acceptable dosemeters are, however, not clearly defined. This paper is the result of a literature overview with regard to assessing the entrance skin dose during radiological examinations by putting a dosemeter on the patient's skin. The relevant intrinsic characteristics, as well as some examples of clinical use of the different detector types, are presented. In this respect, thermoluminescence, scintillation, semiconductor and film dosemeters are discussed and compared with respect to their practical use.

  2. Measurement and control practices in Finnish wastewater networks.

    PubMed

    Poutiainen, H; Heinonen-Tanski, H

    2010-03-01

    In this paper, we describe measurement and control practices in Finnish wastewater networks. We have surveyed the 14 largest wastewater treatment plants in the country, which account for approximately 40% of total Finnish treatment capacity. It was found that these plants still only rely on a few, traditional measurement techniques. The treatment processes could be improved, and the treatment could be made more energy-efficient by installing modern instrumentation. We review some recent developments in wastewater plant instrumentation technology and suggest improvements to Finnish plants.

  3. Expected estimating equations for missing data, measurement error, and misclassification, with application to longitudinal nonignorable missing data.

    PubMed

    Wang, C Y; Huang, Yijian; Chao, Edward C; Jeffcoat, Marjorie K

    2008-03-01

    Missing data, measurement error, and misclassification are three important problems in many research fields, such as epidemiological studies. It is well known that missing data and measurement error in covariates may lead to biased estimation. Misclassification may be considered as a special type of measurement error, for categorical data. Nevertheless, we treat misclassification as a different problem from measurement error because statistical models for them are different. Indeed, in the literature, methods for these three problems were generally proposed separately given that statistical modeling for them are very different. The problem is more challenging in a longitudinal study with nonignorable missing data. In this article, we consider estimation in generalized linear models under these three incomplete data models. We propose a general approach based on expected estimating equations (EEEs) to solve these three incomplete data problems in a unified fashion. This EEE approach can be easily implemented and its asymptotic covariance can be obtained by sandwich estimation. Intensive simulation studies are performed under various incomplete data settings. The proposed method is applied to a longitudinal study of oral bone density in relation to body bone density.

  4. The use of cross-correlation analysis between high-frequency ultrasound images to measure longitudinal median nerve movement.

    PubMed

    Dilley, A; Greening, J; Lynn, B; Leary, R; Morris, V

    2001-09-01

    Impaired nerve movement can lead to nerve injury (e.g., carpal tunnel syndrome). A noninvasive method to measure nerve movement in longitudinal section would enable an extensive analysis of nerve entrapment syndromes. A method has been developed using cross-correlation between successive high-frequency ultrasound (US) images to measure longitudinal movement of nerve and muscle. Control "phantom" experiments demonstrated the accuracy and reliability of this method at velocities of 1-10 mm/s. Increasing the frame interval between the compared frames enabled the accurate calculation of slower velocities. The correlation algorithm successfully measured relative movement when the US transducer was moved 1-3 mm over the surface of the forearm. Median nerve movement was repeatedly measured in the forearm during 30 degrees passive wrist extension in three subjects (range 2.63-4.12 mm) and index finger extension in seven subjects (range 1.59-4.48 mm). Median nerve movement values were consistent with those from cadaver studies.

  5. Longitudinal measurements of MRI-T2 in boys with Duchenne muscular dystrophy: effects of age and disease progression.

    PubMed

    Willcocks, R J; Arpan, I A; Forbes, S C; Lott, D J; Senesac, C R; Senesac, E; Deol, J; Triplett, W T; Baligand, C; Daniels, M J; Sweeney, H L; Walter, G A; Vandenborne, K

    2014-05-01

    Duchenne muscular dystrophy (DMD) is characterized by an increased muscle damage and progressive replacement of muscle by noncontractile tissue. Both of these pathological changes can lengthen the MRI transverse proton relaxation time (T2). The current study measured longitudinal changes in T2 and its distribution in the lower leg of 16 boys with DMD (5-13years, 15 ambulatory) and 15 healthy controls (5-13years). These muscles were chosen to allow extended longitudinal monitoring, due to their slow progression compared with proximal muscles in DMD. In the soleus muscle of boys with DMD, T2 and the percentage of pixels with an elevated T2 (⩾2SD above control mean T2) increased significantly over 1year and 2years, while the width of the T2 histogram increased over 2years. Changes in soleus T2 variables were significantly greater in 9-13years old compared with 5-8years old boys with DMD. Significant correlations between the change in all soleus T2 variables over 2years and the change in functional measures over 2years were found. MRI measurement of muscle T2 in boys with DMD is sensitive to disease progression and shows promise as a clinical outcome measure.

  6. The interference of the model support mast with measurements of the longitudinal and lateral aerodynamic coefficients

    NASA Technical Reports Server (NTRS)

    Vandekreeke, C.; Verriere, J.; Quemard, G.

    1987-01-01

    The effects the single-bottom support masts used in the ONERA S1 and S4 wind tunnels have on aerodynamic data collected with scale model aircraft were examined experimentally and analytically. Systematic studies were performed on the flow characteristics around different diameters for the mounts. Scaling methods used to make data from one wind tunnel correspond to data from the other are described. Airbus 320 models were introduced into the tests and mast-body flow interactions were observed. A summary is presented of restrictions on the mast diameters, relative to cylindrical model diameters, which will minimize the effects the masts have on longitudinal and lateral aerodynamic stability data.

  7. Measurement of longitudinal and transverse spin relaxation rates using the ground-state Hanle effect

    SciTech Connect

    Castagna, N.; Weis, A.

    2011-11-15

    We present a theoretical and experimental study of the resonant circularly-polarized-light-induced Hanle effect in the ground state of Cs vapor atoms in a paraffin-coated cell. The effect manifests itself as a narrow resonance (centered at B=0) in the dependence of the optical transmission coefficient of the vapor on the magnitude of an external magnetic field B(vector sign). We develop a theoretical model that yields an algebraic expression for the shape of these resonances for arbitrary field orientations and arbitrary angular momenta of the states coupled by the exciting light, provided that the light power is kept sufficiently small. An experimental procedure for assessing the range of validity of the model is given. Experiments were carried out on the laser-driven Cs D{sub 1} transition both in longitudinal and transverse field geometries, and the observed line shapes of the corresponding bright and dark resonances give an excellent confirmation of the model predictions. The method is applied for determining the intrinsic longitudinal and transverse relaxation rates of the vector magnetization in the vapor and their dependence on light power.

  8. Measurements and Analysis of Longitudinal HOM Driven Coupled Bunch Modes in PEP-II Rings

    SciTech Connect

    Mastorides, T; Rivetta, C.; Fox, J.D.; Winkle, D.Van; /SLAC

    2008-07-07

    The growth rates of the longitudinal higher-order impedance-driven beam modes have greatly increased since the initial PEP-II design and commissioning. This increase is attributed to the addition of 6 1.2MW RF stations with 8 accelerating cavities in the HER and 2 1.2MW RF stations with 4 accelerating cavities in the LER, which allowed operations at twice the design current and almost four times the luminosity. As a result, the damping requirements for the longitudinal feedback have greatly increased since the design, and the feedback filters and control schemes have evolved during PEP-II operations. In this paper, growth and damping rate data for the higher-order mode (HOM) driven coupled-bunch modes are presented from various PEP-II runs and are compared with historical estimates during commissioning. The effect of noise in the feedback processing channel is also studied. Both the stability and performance limits of the system are analyzed.

  9. Longitudinal intensity oscillations in coronal loops observed with TRACE I. Overview of Measured Parameters

    NASA Astrophysics Data System (ADS)

    De Moortel, I.; Ireland, J.; Walsh, R. W.; Hood, A. W.

    2002-09-01

    In this paper we aim to give a comprehensive overview of geometric and physical properties of longitudinal oscillations in large coronal loops. The 38 examples of propagating disturbances were obtained from the analysis of high cadence, 171 Å TRACE data (JOP 83 and JOP 144). The majority of these outward propagating oscillations are found in the footpoints of large diffuse coronal loop structures, close to active regions. The disturbances travel outward with a propagation speed of the order of v≈122±43 km s-1. The variations in intensity are estimated to be roughly 4.1±1.5% of the background loop brightness. The propagating disturbances are found to be damped very quickly and are typically only detected in the first 8.9±4.4 Mm along the loop. Using a wavelet analysis, periods of the order of 282±93 s are found and the energy flux was estimated as 342±126 erg cm-2 s-1. We found highly filamentary behavior in the lower part of the coronal loops and showed that the intensity oscillations can be present for several consecutive hours, with a more or less constant period. It is evident that the longitudinal oscillations are a widespread, regularly occurring coronal phenomena. A companion paper is devoted to the interpretation and discussion of the results.

  10. Measurement of longitudinal and transverse spin relaxation rates using the ground-state Hanle effect

    NASA Astrophysics Data System (ADS)

    Castagna, N.; Weis, A.

    2011-11-01

    We present a theoretical and experimental study of the resonant circularly-polarized-light-induced Hanle effect in the ground state of Cs vapor atoms in a paraffin-coated cell. The effect manifests itself as a narrow resonance (centered at B=0) in the dependence of the optical transmission coefficient of the vapor on the magnitude of an external magnetic field B⃗. We develop a theoretical model that yields an algebraic expression for the shape of these resonances for arbitrary field orientations and arbitrary angular momenta of the states coupled by the exciting light, provided that the light power is kept sufficiently small. An experimental procedure for assessing the range of validity of the model is given. Experiments were carried out on the laser-driven Cs D1 transition both in longitudinal and transverse field geometries, and the observed line shapes of the corresponding bright and dark resonances give an excellent confirmation of the model predictions. The method is applied for determining the intrinsic longitudinal and transverse relaxation rates of the vector magnetization in the vapor and their dependence on light power.

  11. A generalized longitudinal mixture IRT model for measuring differential growth in learning environments.

    PubMed

    Kadengye, Damazo T; Ceulemans, Eva; Van den Noortgate, Wim

    2014-09-01

    This article describes a generalized longitudinal mixture item response theory (IRT) model that allows for detecting latent group differences in item response data obtained from electronic learning (e-learning) environments or other learning environments that result in large numbers of items. The described model can be viewed as a combination of a longitudinal Rasch model, a mixture Rasch model, and a random-item IRT model, and it includes some features of the explanatory IRT modeling framework. The model assumes the possible presence of latent classes in item response patterns, due to initial person-level differences before learning takes place, to latent class-specific learning trajectories, or to a combination of both. Moreover, it allows for differential item functioning over the classes. A Bayesian model estimation procedure is described, and the results of a simulation study are presented that indicate that the parameters are recovered well, particularly for conditions with large item sample sizes. The model is also illustrated with an empirical sample data set from a Web-based e-learning environment.

  12. Fracture prediction from repeat BMD measurements in clinical practice.

    PubMed

    Leslie, W D; Brennan-Olsen, S L; Morin, S N; Lix, L M

    2016-01-01

    We investigated whether repeat BMD measurements in clinical populations are useful for fracture risk assessment. We report that repeat BMD measurements are a robust predictor of fracture in clinical populations; this is not affected by preceding BMD change or recent osteoporosis therapy. In clinical practice, many patients selectively undergo repeat bone mineral density (BMD) measurements. We investigated whether repeat BMD measurements in clinical populations are useful for fracture risk assessment and whether this is affected by preceding change in BMD or recent osteoporosis therapy. We identified women and men aged ≥ 50 years who had a BMD measurement during 1990-2009 from a large clinical BMD database for Manitoba, Canada (n = 50,215). Patient subgroups aged ≥ 50 years at baseline with repeat BMD measures were identified. Data were linked to an administrative data repository, from which osteoporosis therapy, fracture outcomes, and covariates were extracted. Using Cox proportional hazards models, we assessed covariate-adjusted risk for major osteoporotic fracture (MOF) and hip fracture according to BMD (total hip, lumbar spine, femoral neck) at different time points. Prevalence of osteoporosis therapy increased from 18 % at baseline to 55 % by the fourth measurement. Total hip BMD was predictive of MOF at each time point. In the patient subgroup with two repeat BMD measurements (n = 13,481), MOF prediction with the first and second measurements was similar: adjusted-hazard ratio (HR) per SD 1.45 (95 % CI 1.34-1.56) vs. 1.64 (95 % CI 1.48-1.81), respectively. No differences were seen when the second measurement results were stratified by preceding change in BMD or osteoporosis therapy (both p-interactions >0.2). Similar results were seen for hip fracture prediction and when spine and femoral neck BMD were analyzed. Repeat BMD measurements are a robust predictor of fracture in clinical populations; this is not affected by preceding BMD change or recent

  13. Practical Experience of Discharge Measurement in Flood Conditions with ADP

    NASA Astrophysics Data System (ADS)

    Vidmar, A.; Brilly, M.; Rusjan, S.

    2009-04-01

    Accurate discharge estimation is important for an efficient river basin management and especially for flood forecasting. The traditional way of estimating the discharge in hydrological practice is to measure the water stage and to convert the recorded water stage values into discharge by using the single-valued rating curve .Relationship between the stage and discharge values of the rating curve for the extreme events are usually extrapolated by using different mathematical methods and are not directly measured. Our practice shows that by using the Accoustic Doppler Profiler (ADP) instrument we can record the actual relation between the water stage and the flow velocity at the occurrence of flood waves very successfully. Measurement in flood conditions it is not easy task, because of high water surface velocity and large amounts of sediments in the water and floating objects on the surface like branches, bushes, trees, piles and others which can also easily damage ADP instrument. We made several measurements in such extreme events on the Sava River down to the nuclear power plant Kr\\vsko where we have install fixed cable way. During the several measurement with traditional "moving-boat" measurement technique a mowing bed phenomenon was clearly seen. Measuring flow accurately using ADP that uses the "moving-boat" technique, the system needs a reference against which to relate water velocities to. This reference is river bed and must not move. During flood events we detected difficulty finding a static bed surface to which to relate water velocities. This is caused by motion of the surface layer of bed material or also sediments suspended in the water near bed very densely. So these traditional »moving-boat« measurement techniques that we normally use completely fail. Using stationary measurement method to making individual velocity profile measurements, using an Acoustic Doppler Profiler (ADP), at certain time at fixed locations across the width of a stream gave

  14. A measure to evaluate classroom teaching practices in nursing.

    PubMed

    Herinckx, Heidi; Munkvold, Julia Paschall; Winter, Elisabeth; Tanner, Christine A

    2014-01-01

    The Oregon Consortium for Nursing Education (OCNE) Classroom Teaching Fidelity Scale was created to measure the implementation of the OCNE curriculum and its related pedagogy. OCNE is a partnership of eight community colleges and the five-campus state-supported university. OCNE developed a shared competency-based curriculum and pedagogical practices. An essential part of the OCNE evaluation was to measure the extent the curriculum and pedagogical model were implemented on each partner campus. The scale was developed using a multistep methodology, including review of the literature and OCNE guidelines and materials, frequent consultation with local and national advisory boards, and multiple observations of OCNE classrooms over a two-year period. Fidelity scores are reported for 10 OCNE colleges observed in 2009. CONCLUSlON: The creation and use of this fidelity scale and similar measures may contribute to the emerging science of nursing education by more clearly documenting educational reform efforts..

  15. Longitudinal Effects of MRI-Measured Hepatic Steatosis on Biomarkers of Glucose Homeostasis and Hepatic Apoptosis in Obese Youth

    PubMed Central

    Kim, Grace; Giannini, Cosimo; Pierpont, Bridget; Feldstein, Ariel E.; Santoro, Nicola; Kursawe, Romy; Shaw, Melissa; Duran, Elvira; Goldberg, Rachel; Dziura, James; Caprio, Sonia

    2013-01-01

    OBJECTIVE We used fast-gradient magnetic resonance imaging (MRI) to determine the longitudinal associations between the hepatic fat content (HFF), glucose homeostasis, and a biomarker of hepatocellular apoptosis in obese youth. RESEARCH DESIGN AND METHODS Baseline and longitudinal liver and abdominal MRI were performed with an oral glucose tolerance test in 76 obese youth followed for an average of 1.9 years. Cytokeratin-18 (CK-18) was measured at baseline and follow-up as a biomarker of hepatic apoptosis. The relationship between baseline HFF and metabolic parameters and circulating levels of CK-18 at follow-up were assessed using a bivariate correlation. RESULTS At baseline, 38% had hepatic steatosis based on %HFF ≥5.5% with alterations in indices of insulin sensitivity and secretion. At follow-up, BMI increased in both groups and baseline %HFF correlated strongly with the follow-up %HFF (r = 0.81, P < 0.001). Over time, markers of insulin sensitivity and 2-h glucose improved significantly in the group without fatty liver, in contrast with the persistence of the insulin resistance and associated correlates in the fatty liver group. Baseline HFF correlated with 2-h glucose (r = 0.38, P = 0.001), whole-body insulin sensitivity (r = −0.405, P = 0.001), adiponectin (r = −0.44, P < 0.001), CK-18 levels, (r = 0.63, P < 0.001), and disposition index (r = −0.272, P = 0.021) at follow-up. In a multivariate analysis, we showed that baseline HFF is an independent predictor of 2-h glucose and whole-body insulin sensitivity. CONCLUSIONS In obese youth, the phenotype of MRI-measured hepatic steatosis is persistent. Baseline HFF strongly modulates longitudinally 2-h blood glucose, biomarkers of insulin resistance, and hepatocellular apoptosis. PMID:22933439

  16. A Monte Carlo Power Analysis of Traditional Repeated Measures and Hierarchical Multivariate Linear Models in Longitudinal Data Analysis.

    PubMed

    Fang, Hua; Brooks, Gordon P; Rizzo, Maria L; Espy, Kimberly A; Barcikowski, Robert S

    2008-01-01

    The power properties of traditional repeated measures and hierarchical linear models have not been clearly determined in the balanced design for longitudinal studies in the current literature. A Monte Carlo power analysis of traditional repeated measures and hierarchical multivariate linear models are presented under three variance-covariance structures. Results suggest that traditional repeated measures have higher power than hierarchical linear models for main effects, but lower power for interaction effects. Significant power differences are also exhibited when power is compared across different covariance structures. Results also supplement more comprehensive empirical indexes for estimating model precision via bootstrap estimates and the approximate power for both main effects and interaction tests under standard model assumptions.

  17. Daily Associations Between Drinking and Sex Among College Students: A Longitudinal Measurement Burst Design.

    PubMed

    Patrick, Megan E; Maggs, Jennifer L; Lefkowitz, Eva S

    2015-06-01

    Daily links between alcohol use and sexual behaviors were examined in a longitudinal study of college students. Hierarchical linear models predicted sexual behaviors by characteristics of persons (N=731; Level 3), semesters (N=4,345, Level 2), and days (N=56,372, Level 1). On a given day, consuming more drinks and binge drinking were associated with greater odds of kissing, touching, oral sex, and penetrative sex. Consistent with alcohol myopia and expectancy theories, associations between binge drinking and sexual behaviors were stronger for students not in romantic relationships, for students with stronger alcohol-sex expectancies, and for oral and penetrative sex. Findings suggest that within-day links between alcohol use and sexual behaviors are evident across college, with variations based on individual and relationship factors.

  18. Daily Associations Between Drinking and Sex Among College Students: A Longitudinal Measurement Burst Design

    PubMed Central

    Maggs, Jennifer L.; Lefkowitz, Eva S.

    2015-01-01

    Daily links between alcohol use and sexual behaviors were examined in a longitudinal study of college students. Hierarchical linear models predicted sexual behaviors by characteristics of persons (N=731; Level 3), semesters (N=4,345, Level 2), and days (N=56,372, Level 1). On a given day, consuming more drinks and binge drinking were associated with greater odds of kissing, touching, oral sex, and penetrative sex. Consistent with alcohol myopia and expectancy theories, associations between binge drinking and sexual behaviors were stronger for students not in romantic relationships, for students with stronger alcohol-sex expectancies, and for oral and penetrative sex. Findings suggest that within-day links between alcohol use and sexual behaviors are evident across college, with variations based on individual and relationship factors. PMID:26052189

  19. Reliability measures of functional magnetic resonance imaging in a longitudinal evaluation of mild cognitive impairment.

    PubMed

    Zanto, Theodore P; Pa, Judy; Gazzaley, Adam

    2014-01-01

    As the aging population grows, it has become increasingly important to carefully characterize amnestic mild cognitive impairment (aMCI), a preclinical stage of Alzheimer's disease (AD). Functional magnetic resonance imaging (fMRI) is a valuable tool for monitoring disease progression in selectively vulnerable brain regions associated with AD neuropathology. However, the reliability of fMRI data in longitudinal studies of older adults with aMCI is largely unexplored. To address this, aMCI participants completed two visual working tasks, a Delayed-Recognition task and a One-Back task, on three separate scanning sessions over a three-month period. Test-retest reliability of the fMRI blood oxygen level dependent (BOLD) activity was assessed using an intraclass correlation (ICC) analysis approach. Results indicated that brain regions engaged during the task displayed greater reliability across sessions compared to regions that were not utilized by the task. During task-engagement, differential reliability scores were observed across the brain such that the frontal lobe, medial temporal lobe, and subcortical structures exhibited fair to moderate reliability (ICC=0.3-0.6), while temporal, parietal, and occipital regions exhibited moderate to good reliability (ICC=0.4-0.7). Additionally, reliability across brain regions was more stable when three fMRI sessions were used in the ICC calculation relative to two fMRI sessions. In conclusion, the fMRI BOLD signal is reliable across scanning sessions in this population and thus a useful tool for tracking longitudinal change in observational and interventional studies in aMCI.

  20. Serial Liver Stiffness Measurements and Monitoring of Liver-Transplanted Patients in a Real-Life Clinical Practice

    PubMed Central

    Rinaldi, Luca; Valente, Giovanna; Piai, Guido

    2016-01-01

    Background Liver transplanted patients need close surveillance for early signs of graft disease. Objectives Transient elastography can safely be repeated over time, offering serial liver stiffness measurement values. Serial stiffness measurements were compared to single baseline stiffness measurements in predicting the appearance of liver-related clinical events and guiding subsequent clinical decisions. Methods One hundred and sixty liver transplanted patients were observed for three years in our real-life practice. Results Liver stiffness measurements were stable in 75% of patients, decreased in 4% of patients, and increased in 21% of patients. The pattern of increased stiffness measurements was associated with both HCV-RNA positive status and the presence of an active biliary complication of liver transplantation and was more predictive of a clinically significant event resulting from any disease of the transplanted liver when compared to a stable pattern or to a single liver stiffness measurement. The procedures that were consequently performed were often diagnostic for unexpected situations, both in HCV-RNA positive and HCV-RNA negative patients. Conclusions The pattern of longitudinally increased liver stiffness measurements efficiently supported clinical decisions for individualized management strategies. Repeated transient elastography in real-life clinical practice appears to have a practical role in monitoring liver transplanted patients. PMID:28123442

  1. Rapid and Progressive Regional Brain Atrophy in CLN6 Batten Disease Affected Sheep Measured with Longitudinal Magnetic Resonance Imaging

    PubMed Central

    Sawiak, Stephen J.; Perumal, Sunthara Rajan; Rudiger, Skye R.; Matthews, Loren; Mitchell, Nadia L.; McLaughlan, Clive J.; Bawden, C. Simon; Palmer, David N.; Kuchel, Timothy; Morton, A. Jennifer

    2015-01-01

    Variant late-infantile Batten disease is a neuronal ceroid lipofuscinosis caused by mutations in CLN6. It is a recessive genetic lysosomal storage disease characterised by progressive neurodegeneration. It starts insidiously and leads to blindness, epilepsy and dementia in affected children. Sheep that are homozygous for a natural mutation in CLN6 have an ovine form of Batten disease Here, we used in vivo magnetic resonance imaging to track brain changes in 4 unaffected carriers and 6 affected Batten disease sheep. We scanned each sheep 4 times, between 17 and 22 months of age. Cortical atrophy in all sheep was pronounced at the baseline scan in all affected Batten disease sheep. Significant atrophy was also present in other brain regions (caudate, putamen and amygdala). Atrophy continued measurably in all of these regions during the study. Longitudinal MRI in sheep was sensitive enough to measure significant volume changes over the relatively short study period, even in the cortex, where nearly 40% of volume was already lost at the start of the study. Thus longitudinal MRI could be used to study the dynamics of progression of neurodegenerative changes in sheep models of Batten disease, as well as to assess therapeutic efficacy. PMID:26161747

  2. Assessing patient reported outcome measures: A practical guide for gastroenterologists

    PubMed Central

    Hutchings, Hayley A; Williams, John G

    2014-01-01

    Gastrointestinal illnesses cause physical, emotional and social impact on patients. Patient reported outcome measures (PROMs) are increasingly used in clinical decision-making, clinical research and approval of new therapies. In the last decade, there has been a rapid increase in the number of PROMs in gastroenterology and, therefore, the choice between which of these PROMs to use can be difficult. Not all PROM instruments currently used in research and clinical practice in gastroenterology have gone through a rigorous development methodology. New drugs and therapies will not have access to the market if the PROMs used in their clinical trials are not validated according to the guidelines of the international agencies. Therefore, it is important to know the required properties of PROMs when choosing or evaluating a drug or a clinical intervention. This paper reviews the current literature on how to assess the validity and reliability of PROMs. It summarises the required properties into a practical guide for gastroenterologists to use in assessing an instrument for use in clinical practice or research. PMID:25452841

  3. Pitfalls of converting practice guidelines into quality measures: lessons learned from a VA performance measure.

    PubMed

    Walter, Louise C; Davidowitz, Natalie P; Heineken, Paul A; Covinsky, Kenneth E

    2004-05-26

    The Department of Veterans Affairs (VA) manages the largest health care system in the United States, and the Institute of Medicine has recommended that many practices of VA quality measurement be applied to the US health care system as a whole. The VA measures quality of care at all of its sites by assessing adherence rates to performance measures, which generally are derived from evidence-based practice guidelines. Higher adherence rates are used as evidence of better quality of care. However, there are problems with converting practice guidelines, intended to offer guidance to clinicians, into performance measures that are meant to identify poor-quality care. We suggest a more balanced perspective on the use of performance measures to define quality by delineating conceptual problems with the conversion of practice guidelines into quality measures. Focusing on colorectal cancer screening, we use a case study at 1 VA facility to illustrate pitfalls that can cause adherence rates to guideline-based performance measures to be poor indicators of the quality of cancer screening. Pitfalls identified included (1) not properly considering illness severity of the sample population audited for adherence to screening, (2) not distinguishing screening from diagnostic procedures when setting achievable target screening rates, and (3) not accounting for patient preferences or clinician judgment when scoring performance measures. For many patients with severe comorbid illnesses or strong preferences against screening, the risks of colorectal cancer screening outweigh the benefits, and the decision to not screen may reflect good quality of care. Performance measures require more thoughtful specification and interpretation to avoid defining high testing rates as good quality of care regardless of who received the test, why it was performed, or whether the patient wanted it.

  4. Score-based tests of measurement invariance: use in practice

    PubMed Central

    Wang, Ting; Merkle, Edgar C.; Zeileis, Achim

    2014-01-01

    In this paper, we consider a family of recently-proposed measurement invariance tests that are based on the scores of a fitted model. This family can be used to test for measurement invariance w.r.t. a continuous auxiliary variable, without pre-specification of subgroups. Moreover, the family can be used when one wishes to test for measurement invariance w.r.t. an ordinal auxiliary variable, yielding test statistics that are sensitive to violations that are monotonically related to the ordinal variable (and less sensitive to non-monotonic violations). The paper is specifically aimed at potential users of the tests who may wish to know (1) how the tests can be employed for their data, and (2) whether the tests can accurately identify specific models parameters that violate measurement invariance (possibly in the presence of model misspecification). After providing an overview of the tests, we illustrate their general use via the R packages lavaan and strucchange. We then describe two novel simulations that provide evidence of the tests' practical abilities. As a whole, the paper provides researchers with the tools and knowledge needed to apply these tests to general measurement invariance scenarios. PMID:24936190

  5. Longitudinal examination of objectively-measured physical activity and sedentary time among children with and without significant movement impairments.

    PubMed

    Kwan, Matthew Y W; King-Dowling, Sara; Hay, John A; Faught, Brent E; Cairney, John

    2016-06-01

    Children with Developmental Coordination Disorder (DCD) tend to be less active than typically-developing (TD) children. Current evidence, however, is based on cross-sectional and self-reported activity, and little is known about sedentary time among children with significant movement impairments such as DCD. The current study examines the longitudinal patterns of objectively measured physical activity and sedentary time in children with and without possible DCD (pDCD). Data is from a longitudinal nested case-control study, with 103 participants (n=60 males ages=12 and 13 at baseline). Participants averaging ⩽16th percentile on the Movement Assessment Battery for Children were considered having significant movement impairments and pDCD (n=49). All participants wore accelerometers for seven days. There were significant main effects for time (Estimate=-23.98, p<.01) and gender (Estimate=59.86, p<.05) on total physical activity, and time spent being sedentary (Estimate=15.58, p<.05). Significant main effects for pDCD (Estimate=-5.38, p<.05) and gender (Estimate=26.89, p<.01), and time by gender interaction (Estimate=-7.50, p<.05) were found for moderate-to-vigorous physical activity (MVPA). Sedentary time did not differ between children with and without DCD. Results suggest children with pDCD engaged in less MVPA compared to TD children. Consistent patterns of MVPA over time, however, suggest that the divergence in MVPA occurs earlier in childhood. Further longitudinal research following a younger cohort is necessary to identify the specific point that differences in MVPA emerge. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. [Practical aspects of partition measurements according to GLP rules].

    PubMed

    Takácsné Novák, K

    1997-09-01

    Experimental methods for octanol/water partition coefficient (logP) determination are surveyed. The terminology used in the literature, the lipophilicity/pH profile and the most important factors influencing the logP values have been discussed. Several new, recently developed direct logP determination methods are introduced including their advantages and limits of application. Some aspects of good laboratory practice of the shake-flask method are described and results of a validation study of pH-metric logP determination technique used PCA 101 pKa and logP analyser (Sirius, UK) are also shown. Questions have to be answered in method selection for logP measurement are summarized in flow chart (Fig. 8). The author based on her own experiences in lipophilicity measurements over decades, suggests the shake-flask method and the automated dual-phase potentiometric technique, as approaches fulfilling the GLP rules.

  7. Practical aspects of measuring intracellular calcium signals with fluorescent indicators.

    PubMed

    Kao, Joseph P Y; Li, Gong; Auston, Darryl A

    2010-01-01

    The use of fluorescent indicators for monitoring calcium (Ca(2+)) signals and for measuring Ca(2+) concentration ([Ca(2+)]) in living cells is described. The following topics are covered in detail: (1) ratiometric and nonratiometric fluorescent indicators and the principles underlying their use, (2) techniques for loading Ca(2+) indicators and Ca(2+) buffers into living cells, (3) calibration of indicator fluorescence intensity measurements to yield values of intracellular [Ca(2+)], (4) analysis of nonratiometric fluorescence intensity data and caveats relating to their interpretation, (5) techniques for manipulating intracellular and extracellular [Ca(2+)], and (6) the use of fluorescent indicators to monitor Ca(2+) signals in mitochondria. The chapter aims to present these fundamental topics in a manner that is practically useful and intuitively accessible. The origins of key mathematical equations used in the article are outlined in two appendices.

  8. Practical and simple circuitry for the measurement of small capacitance

    NASA Astrophysics Data System (ADS)

    Lin, D. Y.; Wu, J. D.; Chang, Y. J.; Wu, J. S.

    2007-01-01

    Practical and cost-effective circuitry with high sensitivity has been developed to measure a small capacitance using current compensation method. The circuitry uses an electronic switch to periodically connect or separate the capacitor under test (Cx) from a reference capacitor (Cr). When Cx is connected in parallel with Cr the total capacitance becomes Cx+Cr. On the other hand, as Cx is separated from Cr, the total capacitance is only Cr. This periodic change of the capacitance generates a periodic square-wave output with an amplitude in proportion to the capacitance of Cx. A high sensitivity of ΔV /ΔC=202.2mV/pF has been achieved, making the circuitry a powerful tool in measuring small capacitances. Three applications have been performed to present its capability: (a) displacement, (b) height of liquid, and (c) angle of tilt. The experimental results demonstrate the performance of the circuitry.

  9. Codifference as a practical tool to measure interdependence

    NASA Astrophysics Data System (ADS)

    Wyłomańska, Agnieszka; Chechkin, Aleksei; Gajda, Janusz; Sokolov, Igor M.

    2015-03-01

    Correlation and spectral analysis represent the standard tools to study interdependence in statistical data. However, for the stochastic processes with heavy-tailed distributions such that the variance diverges, these tools are inadequate. The heavy-tailed processes are ubiquitous in nature and finance. We here discuss codifference as a convenient measure to study statistical interdependence, and we aim to give a short introductory review of its properties. By taking different known stochastic processes as generic examples, we present explicit formulas for their codifferences. We show that for the Gaussian processes codifference is equivalent to covariance. For processes with finite variance these two measures behave similarly with time. For the processes with infinite variance the covariance does not exist, however, the codifference is relevant. We demonstrate the practical importance of the codifference by extracting this function from simulated as well as real data taken from turbulent plasma of fusion device and financial market. We conclude that the codifference serves as a convenient practical tool to study interdependence for stochastic processes with both infinite and finite variances as well.

  10. Single and double spin asymmetries for deeply virtual Compton scattering measured with CLAS and a longitudinally polarized proton target

    SciTech Connect

    Pisano, S.; Biselli, A.; Niccolai, S.; Seder, E.; Guidal, M.; Mirazita, M.; Adhikari, K. P.; Adikaram, D.; Amaryan, M. J.; Anderson, M. D.; Anefalos Pereira, S.; Avakian, H.; Ball, J.; Battaglieri, M.; Batourine, V.; Bedlinskiy, I.; Bosted, P.; Briscoe, B.; Brock, J.; Brooks, W. K.; Burkert, V. D.; Carlin, C.; Carman, D. S.; Celentano, A.; Chandavar, S.; Charles, G.; Colaneri, L.; Cole, P. L.; Compton, N.; Contalbrigo, M.; Cortes, O.; Crabb, D. G.; Crede, V.; D' Angelo, A.; De Vita, R.; De Sanctis, E.; Deur, A.; Djalali, C.; Dupre, R.; Egiyan, H.; El Alaoui, A.; El Fassi, L.; Elouadrhiri, L.; Eugenio, P.; Fedotov, G.; Fegan, S.; Fersch, R.; Filippi, A.; Fleming, J. A.; Fradi, A.; Garillon, B.; Garcon, M.; Ghandilyan, Y.; Gilfoyle, G. P.; Giovanetti, K. L.; Girod, F. X.; Goetz, J. T.; Gohn, W.; Golovatch, E.; Gothe, R. W.; Griffioen, K. A.; Guo, L.; Hafidi, K.; Hanretty, C.; Hattawy, M.; Hicks, K.; Holtrop, M.; Hughes, S. M.; Ilieva, Y.; Ireland, D. G.; Ishkhanov, B. S.; Jenkins, D.; Jiang, X.; Jo, H. S.; Joo, K.; Joosten, S.; Keith, C. D.; Keller, D.; Kim, A.; Kim, W.; Klein, F. J.; Kubarovsky, V.; Kuhn, S. E.; Lenisa, P.; Livingston, K.; Lu, H. Y.; MacCormick, M.; MacGregor, Ian J. D.; Mayer, M.; McKinnon, B.; Meekins, D. G.; Meyer, C. A.; Mokeev, V.; Montgomery, R. A.; Moody, C. I.; Munoz Camacho, C.; Nadel-Turonski, P.; Osipenko, M.; Ostrovidov, A. I.; Park, K.; Phelps, W.; Phillips, J. J.; Pogorelko, O.; Price, J. W.; Procureur, S.; Prok, Y.; Puckett, A. J. R.; Ripani, M.; Rizzo, A.; Rosner, G.; Rossi, P.; Roy, P.; Sabatie, F.; Salgado, C.; Schott, D.; Schumacher, R. A.; Skorodumina, I.; Smith, G. D.; Sober, D. I.; Sokhan, D.; Sparveris, N.; Stepanyan, S.; Stoler, P.; Strauch, S.; Sytnik, V.; Tian, Ye; Tkachenko, S.; Turisini, M.; Ungaro, M.; Voutier, E.; Walford, N. K.; Watts, D. P.; Wei, X.; Weinstein, L. B.; Wood, M. H.; Zachariou, N.; Zana, L.; Zhang, J.; Zhao, Z. W.; Zonta, I.

    2015-03-19

    Single-beam, single-target, and double-spin asymmetries for hard exclusive photon production on the proton e→p→e'p'γ are presented. The data were taken at Jefferson Lab using the CLAS detector and a longitudinally polarized 14NH3 target. The three asymmetries were measured in 165 4-dimensional kinematic bins, covering the widest kinematic range ever explored simultaneously for beam and target-polarization observables in the valence quark region. The kinematic dependences of the obtained asymmetries are discussed and compared to the predictions of models of Generalized Parton Distributions. As a result, the measurement of three DVCS spin observables at the same kinematic points allows a quasi-model-independent extraction of the imaginary parts of the H and H~ Compton Form Factors, which give insight into the electric and axial charge distributions of valence quarks in the proton.

  11. Practical considerations for measuring hydrogen concentrations in groundwater

    USGS Publications Warehouse

    Chapelle, F.H.; Vroblesky, D.A.; Woodward, J.C.; Lovley, D.R.

    1997-01-01

    Several practical considerations for measuring concentrations of dissolved molecular hydrogen (H2) in groundwater including 1 sampling methods 2 pumping methods and (3) effects of well casing materials were evaluated. Three different sampling methodologies (a downhole sampler, a gas- stripping method, and a diffusion sampler) were compared. The downhole sampler and gas-stripping methods gave similar results when applied to the same wells, the other hand, appeared to The diffusion sampler, on overestimate H2 concentrations relative to the downhole sampler. Of these methods, the gas-stripping method is better suited to field conditions because it is faster (~ 30 min for a single analysis as opposed to 2 h for the downhole sampler or 8 h for the diffusion sampler), the analysis is easier (less sample manipulation is required), and the data computations are more straightforward (H2 concentrations need not be corrected for water sample volume). Measurement of H2 using the gas-stripping method can be affected by different pumping equipment. Peristaltic, piston, and bladder pumps all gave similar results when applied to water produced from the same well. It was observed, however, that peristaltic-pumped water (which draws water under a negative pressure) enhanced the gas-stripping process and equilibrated slightly faster than either piston or bladder pumps (which push water under a positive pressure). A direct current(dc) electrically driven submersible pump was observed to produce H2 and was not suitable for measuring H2 in groundwater. Measurements from two field sites indicate that iron or steel well casings, produce H2, which masks H2 concentrations in groundwater. PVC-cased wells or wells cased with other materials that do not produce H2 are necessary for measuring H2 concentrations in groundwater.Several practical considerations for measuring concentrations of dissolved molecular hydrogen in groundwater including sampling methods, pumping methods, and effects of

  12. Longitudinal measures of cholinergic forebrain atrophy in the transition from healthy aging to Alzheimer's disease.

    PubMed

    Grothe, Michel; Heinsen, Helmut; Teipel, Stefan

    2013-04-01

    Recent evidence from cross-sectional in vivo imaging studies suggests that atrophy of the cholinergic basal forebrain (BF) in Alzheimer's disease (AD) can be distinguished from normal age-related degeneration even at predementia stages of the disease. Longitudinal study designs are needed to specify the dynamics of BF degeneration in the transition from normal aging to AD. We applied recently developed techniques for in vivo volumetry of the BF to serial magnetic resonance imaging scans of 82 initially healthy elderly individuals (60-93 years) and 50 patients with very mild AD (Clinical Dementia Rating score = 0.5) that were clinically followed over an average of 3 ± 1.5 years. BF atrophy rates were found to be significantly higher than rates of global brain shrinkage even in cognitively stable healthy elderly individuals. Compared with healthy control subjects, very mild AD patients showed reduced BF volumes at baseline and increased volume loss over time. Atrophy of the BF was more pronounced in progressive patients compared with those that remained stable. The cholinergic BF undergoes disproportionate degeneration in the aging process, which is further increased by the presence of AD.

  13. Middle-Class African American Adolescents' and Parents' Conceptions of Parental Authority and Parenting Practices: A Longitudinal Investigation.

    ERIC Educational Resources Information Center

    Smetana, Judith G.

    2000-01-01

    Examined longitudinally conceptions of parental authority and ratings of parental rules and decision-making among middle- class African American adolescents and their parents. Found that nearly all subjects affirmed parents' legitimate authority to regulate and children's obligation to comply regarding oral, conventional, prudential, friendship,…

  14. Salvadoran Campesinos/as' Literacy Practices and Perceptions of the Benefits of Literacy: A Longitudinal Study with Former Literacy Participants

    ERIC Educational Resources Information Center

    Prins, Esther

    2010-01-01

    This article uses data from longitudinal, ethnographic research to examine how, six years after attending literacy classes, 12 adults in rural El Salvador used literacy, their perceptions of the temporary and longer-term psychosocial and economic benefits of literacy education, and their memories of literacy classes. The findings support prior…

  15. Practical remarks on the heart rate and saturation measurement methodology

    NASA Astrophysics Data System (ADS)

    Kowal, M.; Kubal, S.; Piotrowski, P.; Staniec, K.

    2017-05-01

    A surface reflection-based method for measuring heart rate and saturation has been introduced as one having a significant advantage over legacy methods in that it lends itself for use in special applications such as those where a person’s mobility is of prime importance (e.g. during a miner’s work) and excluding the use of traditional clips. Then, a complete ATmega1281-based microcontroller platform has been described for performing computational tasks of signal processing and wireless transmission. In the next section remarks have been provided regarding the basic signal processing rules beginning with raw voltage samples of converted optical signals, their acquisition, storage and smoothing. This chapter ends with practical remarks demonstrating an exponential dependence between the minimum measurable heart rate and the readout resolution at different sampling frequencies for different cases of averaging depth (in bits). The following section is devoted strictly to the heart rate and hemoglobin oxygenation (saturation) measurement with the use of the presented platform, referenced to measurements obtained with a stationary certified pulsoxymeter.

  16. Changes in spectral measures and voice-onset time with age: a cross-sectional and a longitudinal study.

    PubMed

    Decoster, W; Debruyne, F

    1997-01-01

    In this study, we searched for changes in spectral features (during the sustained vowels [a] and [i]) and the voice onset time (VOT, of [pa] and [ka]) of the ageing voice. A longitudinal study (on 20 participants) and a cross-sectional study (on 265 participants) were conducted. The spectral parameters under consideration were: the difference in amplitude between the first and the second harmonic, the energy difference between the frequency band below 1 kHz and 2-4 kHz, and the energy difference between < 1 kHz and 4-5 kHz. The VOT was also measured. Comparing five age bands of men and women, the cross-sectional study revealed a stronger H2 relative to H1 for women above 60 years pronouncing both vowels [a] and [i]. A relatively stronger spectral level was found between 4 and 5 kHz in elderly men and women (60+) for [i] compared to young men and women (20-29 years). Significant differences in the longitudinal study were not identical to those of the cross-sectional study. After a time interval of 30 years, 20 men produced a relatively weaker 2- to 4-kHz part of the spectrum and the VOT became much longer. It was impossible to attribute the changes purely to the process of ageing. Situations and emotions also play an important role and contribute to the different findings of the two groups of participants under consideration.

  17. Reference intervals, longitudinal analyses, and index of individuality of commonly measured laboratory variables in captive bald eagles (Haliaeetus leucocephalus).

    PubMed

    Jones, Michael P; Arheart, Kristopher L; Cray, Carolyn

    2014-06-01

    The objectives of this study were to determine reference intervals, perform longitudinal analyses, and determine the index of individuality (IoI) of 8 hematologic, and 13 biochemical and electrophoretic variables for a group of captive bald eagles (Haliaeetus leucocephalus). Reference intervals were determined from blood samples collected during annual wellness examinations for 41 eagles (23 male and 18 female) with ages ranging between 6 and 43 years (18.7 +/- 7.4, mean +/- SD) at the time of sample collection. Longitudinal analyses and IoI were determined for measured hematologic, biochemical, and protein electrophoretic variables, both individually and as a group, for a subset of 16 eagles (10 male and 6 female) during a 12-year period. This smaller group of eagles ranged in age between 2 and 20 years at the start of the study period, and between 14 and 32 years (21.9 +/- 5.0, mean +/- SD) at the end of the study period. Significant increases with age within the group of 16 eagles were observed only for red blood cells, percent heterophils, total protein, and beta-globulin protein fraction, while albumin:globulin decreased significantly with age. A low IoI (> or = 1.4) was determined for all hematologic and biochemical variables except gamma globulins, which had high IoI (< or = 0.6) for 3 individuals within the subset of 16.

  18. Measurement of Quality of Nursing Practice in Congenital Cardiac Care.

    PubMed

    Connor, Jean Anne; Mott, Sandra; Green, Angela; Larson, Carol; Hickey, Patricia

    2016-03-01

    The impact of nursing care on patients' outcomes has been demonstrated in adult and pediatric settings. However, limited attention has been given to standardized measurement of pediatric nursing care. A collaborative group, the Consortium for Congenital Cardiac Care Measurement of Nursing Practice, was formed to address this gap. The purpose of this study was to assess the current state of measurement of the quality of pediatric cardiovascular nursing in freestanding children's hospitals across the United States. A qualitative descriptive design was used to assess the state of measurement of nursing care from the perspective of experts in pediatric cardiovascular nursing. Nurse leaders from 20 sites participated in audiotaped phone interviews. The data were analyzed by using conventional content analysis. Each level of data coding was increasingly comprehensive. Guided by Donabedian's quality framework of structure, process, and outcome, 2 encompassing patterns emerged: (1) structure and process of health care delivery and (2) structure and process of evaluation of care. Similarities in the structure of health care delivery included program expansion and subsequent hiring of nurses with a bachelor of science in nursing and experienced nurses to provide safety and optimal outcomes for patients. Programs varied in how they evaluated care in terms of structure, measurement, collection and dissemination of data. External factors and response to internal processes of health care delivery were similar in different programs; evaluation was more varied. Seven opportunities for measurement that address both structure and process of nursing care were identified to be developed as benchmarks. ©2016 American Association of Critical-Care Nurses.

  19. Longitudinal Assessment of Verbal Learning and Memory in Amnestic Mild Cognitive Impairment: Practice Effects and Meaningful Changes

    PubMed Central

    Campos-Magdaleno, María; Facal, David; Lojo-Seoane, Cristina; Pereiro, Arturo X.; Juncos-Rabadán, Onésimo

    2017-01-01

    Objectives: To identify learning effects and meaningful changes in amnestic mild cognitive impairment (aMCI) at a follow-up assessment. Method: The Spanish version of the California Verbal Learning Test (CVLT) was administered to a sample of 274 adults of age over 50 years with subjective memory complains (SMC), including single and multiple domain aMCI groups and participants with SMC but without cognitive impairment (SMC group). The Wilcoxon test was used to compare results at baseline and after 18 months in short and long recall, and standardized regression-based (SRB) methods were used to study meaningful changes. Results: Scores were significantly higher at follow-up for short and long-delayed recall in all groups indicating generalized practice effect. SRB scores indicated a significant decline in recall in a higher proportion of participants with aMCI than in SMC group. Discussion: Patients with multiple and single domain aMCI benefit from practice in a verbal learning memory test. The SRB approach revealed a higher incidence of meaningful decline in short and long-delay recall and recognition in the aMCI groups than in the SMC group. Specifically, compared to SMC participants, single-domain aMCI individuals declined in a higher proportion in all measures, and multiple-domain aMCI individuals in long delay free recall. PMID:28775700

  20. Measuring parent food practices: a systematic review of existing measures and examination of instruments

    PubMed Central

    2013-01-01

    During the last decade, there has been a rapid increase in development of instruments to measure parent food practices. Because these instruments often measure different constructs, or define common constructs differently, an evaluation of these instruments is needed. A systematic review of the literature was conducted to identify existing measures of parent food practices and to assess the quality of their development. The initial search used terms capturing home environment, parenting behaviors, feeding practices and eating behaviors, and was performed in October of 2009 using PubMed/Medline, PsychInfo, Web of knowledge (ISI), and ERIC, and updated in July of 2012. A review of titles and abstracts was used to narrow results, after which full articles were retrieved and reviewed. Only articles describing development of measures of parenting food practices designed for families with children 2-12 years old were retained for the current review. For each article, two reviewers extracted data and appraised the quality of processes used for instrument development and evaluation. The initial search yielded 28,378 unique titles; review of titles and abstracts narrowed the pool to 1,352 articles; from which 57 unique instruments were identified. The review update yielded 1,772 new titles from which14 additional instruments were identified. The extraction and appraisal process found that 49% of instruments clearly identified and defined concepts to be measured, and 46% used theory to guide instrument development. Most instruments (80%) had some reliability testing, with internal consistency being the most common (79%). Test-retest or inter-rater reliability was reported for less than half the instruments. Some form of validity evidence was reported for 84% of instruments. Construct validity was most commonly presented (86%), usually with analysis of associations with child diet or weight/BMI. While many measures of food parenting practices have emerged, particularly in

  1. Measuring parent food practices: a systematic review of existing measures and examination of instruments.

    PubMed

    Vaughn, Amber E; Tabak, Rachel G; Bryant, Maria J; Ward, Dianne S

    2013-05-20

    During the last decade, there has been a rapid increase in development of instruments to measure parent food practices. Because these instruments often measure different constructs, or define common constructs differently, an evaluation of these instruments is needed. A systematic review of the literature was conducted to identify existing measures of parent food practices and to assess the quality of their development. The initial search used terms capturing home environment, parenting behaviors, feeding practices and eating behaviors, and was performed in October of 2009 using PubMed/Medline, PsychInfo, Web of knowledge (ISI), and ERIC, and updated in July of 2012. A review of titles and abstracts was used to narrow results, after which full articles were retrieved and reviewed. Only articles describing development of measures of parenting food practices designed for families with children 2-12 years old were retained for the current review. For each article, two reviewers extracted data and appraised the quality of processes used for instrument development and evaluation. The initial search yielded 28,378 unique titles; review of titles and abstracts narrowed the pool to 1,352 articles; from which 57 unique instruments were identified. The review update yielded 1,772 new titles from which14 additional instruments were identified. The extraction and appraisal process found that 49% of instruments clearly identified and defined concepts to be measured, and 46% used theory to guide instrument development. Most instruments (80%) had some reliability testing, with internal consistency being the most common (79%). Test-retest or inter-rater reliability was reported for less than half the instruments. Some form of validity evidence was reported for 84% of instruments. Construct validity was most commonly presented (86%), usually with analysis of associations with child diet or weight/BMI. While many measures of food parenting practices have emerged, particularly in

  2. Practical measurement of affordability: an application to medicines.

    PubMed

    Niëns, L M; Van de Poel, E; Cameron, A; Ewen, M; Laing, R; Brouwer, W B F

    2012-03-01

    To develop two practical methods for measuring the affordability of medicines in developing countries. The proposed methods--catastrophic and impoverishment methods--rely on easily accessible aggregated expenditure data and take into account a country's income distribution and absolute level of income. The catastrophic method quantifies the proportion of the population whose resources would be catastrophically reduced by spending on a given medicine; the impoverishment method estimates the proportion of the population that would be pushed below the poverty line by procuring a given medicine. These methods are illustrated by calculating the affordability of glibenclamide, an antidiabetic drug, in India and Indonesia. The results were validated by comparing them with the results obtained by using household micro data for India and Indonesia. When accurate aggregate data are available, the proposed methods offer a practical way to obtain informative and accurate estimates of affordability. Their results are very similar to those obtained with household micro data analysis and are easily compared across countries. The catastrophic and impoverishment methods, based on macro data, can provide a suitable estimate of medicine affordability when the household level micro data needed to carry out more sophisticated studies are not available. Their usefulness depends on the availability of accurate aggregated data.

  3. Why use automated office blood pressure measurements in clinical practice?

    PubMed

    Andreadis, Emmanuel A; Angelopoulos, Epameinondas T; Agaliotis, Gerasimos D; Tsakanikas, Athanasios P; Mousoulis, George P

    2011-09-01

    Automated office blood pressure (AOBP) measurement with the patient resting alone in a quiet examining room can eliminate the white-coat effect associated with conventional readings taken by manual sphygmomanometer. The key to reducing the white-coat response appears to be multiple blood pressure (BP) readings taken in a non-observer office setting, thus eliminating any interaction that could provoke an office-induced increase in BP. Furthermore, AOBP readings have shown a higher correlation with the mean awake ambulatory BP compared with BP readings recorded in routine clinical practice. Although there is a paucity of studies connecting AOBP with organ damage, AOBP values were recently found to be equally associated with left ventricular mass index as those of ambulatory BP. This concludes that in contrast to routine manual office BP, AOBP readings compare favourably with 24-hour ambulatory BP measurements in the appraisal of cardiac remodelling and, as such, could be complementary to ambulatory readings in a way similar to home BP measurements.

  4. Are There Linguistic Markers of Suicidal Writing That Can Predict the Course of Treatment? A Repeated Measures Longitudinal Analysis.

    PubMed

    Brancu, Mira; Jobes, David; Wagner, Barry M; Greene, Jeffrey A; Fratto, Timothy A

    2016-07-02

    The purpose of this pilot study was to predict resolution of suicidal ideation and risk over the course of therapy among suicidal outpatients (N = 144) using a novel method for analyzing Self- verses Relationally oriented qualitative written responses to the Suicide Status Form (SSF). A content analysis software program was used to extract word counts and a repeated measures longitudinal design was implemented to assess improvement over time. Patients with primarily Relationally focused word counts were more likely to have a quicker suicide risk resolution than those with more Self-focused word counts (6-7 sessions versus 17-18 sessions). Implications of these data are discussed, including the potential for enhancing treatment outcomes using this method with individuals entering treatment.

  5. Measurement of parity-violating spin asymmetries in W± production at midrapidity in longitudinally polarized p +p collisions

    NASA Astrophysics Data System (ADS)

    Adare, A.; Aidala, C.; Ajitanand, N. N.; Akiba, Y.; Akimoto, R.; Alexander, J.; Alfred, M.; Aoki, K.; Apadula, N.; Aramaki, Y.; Asano, H.; Aschenauer, E. C.; Atomssa, E. T.; Awes, T. C.; Azmoun, B.; Babintsev, V.; Bai, M.; Bai, X.; Bandara, N. S.; Bannier, B.; Barish, K. N.; Bassalleck, B.; Bathe, S.; Baublis, V.; Baumann, C.; Baumgart, S.; Bazilevsky, A.; Beaumier, M.; Beckman, S.; Belmont, R.; Berdnikov, A.; Berdnikov, Y.; Black, D.; Blau, D. S.; Bok, J. S.; Boyle, K.; Brooks, M. L.; Bryslawskyj, J.; Buesching, H.; Bumazhnov, V.; Butsyk, S.; Campbell, S.; Chen, C.-H.; Chi, C. Y.; Chiu, M.; Choi, I. J.; Choi, J. B.; Choi, S.; Choudhury, R. K.; Christiansen, P.; Chujo, T.; Chvala, O.; Cianciolo, V.; Citron, Z.; Cole, B. A.; Connors, M.; Cronin, N.; Crossette, N.; Csanád, M.; Csörgő, T.; Dairaku, S.; Danley, T. W.; Datta, A.; Daugherity, M. S.; David, G.; Deblasio, K.; Dehmelt, K.; Denisov, A.; Deshpande, A.; Desmond, E. J.; Dietzsch, O.; Ding, L.; Dion, A.; Diss, P. B.; Do, J. H.; Donadelli, M.; D'Orazio, L.; Drapier, O.; Drees, A.; Drees, K. A.; Durham, J. M.; Durum, A.; Edwards, S.; Efremenko, Y. V.; Engelmore, T.; Enokizono, A.; En'yo, H.; Esumi, S.; Eyser, K. O.; Fadem, B.; Feege, N.; Fields, D. E.; Finger, M.; Finger, M.; Fleuret, F.; Fokin, S. L.; Frantz, J. E.; Franz, A.; Frawley, A. D.; Fukao, Y.; Fusayasu, T.; Gainey, K.; Gal, C.; Gallus, P.; Garg, P.; Garishvili, A.; Garishvili, I.; Ge, H.; Giordano, F.; Glenn, A.; Gong, X.; Gonin, M.; Goto, Y.; Granier de Cassagnac, R.; Grau, N.; Greene, S. V.; Grosse Perdekamp, M.; Gu, Y.; Gunji, T.; Guragain, H.; Hachiya, T.; Haggerty, J. S.; Hahn, K. I.; Hamagaki, H.; Hamilton, H. F.; Han, S. Y.; Hanks, J.; Hasegawa, S.; Haseler, T. O. S.; Hashimoto, K.; Hayano, R.; Hayashi, S.; He, X.; Hemmick, T. K.; Hester, T.; Hill, J. C.; Hollis, R. S.; Homma, K.; Hong, B.; Horaguchi, T.; Hoshino, T.; Hotvedt, N.; Huang, J.; Huang, S.; Ichihara, T.; Iinuma, H.; Ikeda, Y.; Imai, K.; Imazu, Y.; Imrek, J.; Inaba, M.; Iordanova, A.; Isenhower, D.; Isinhue, A.; Ivanishchev, D.; Jacak, B. V.; Javani, M.; Jeon, S. J.; Jezghani, M.; Jia, J.; Jiang, X.; Johnson, B. M.; Joo, E.; Joo, K. S.; Jouan, D.; Jumper, D. S.; Kamin, J.; Kanda, S.; Kang, B. H.; Kang, J. H.; Kang, J. S.; Kapustinsky, J.; Karatsu, K.; Kawall, D.; Kazantsev, A. V.; Kempel, T.; Key, J. A.; Khachatryan, V.; Khandai, P. K.; Khanzadeev, A.; Kihara, K.; Kijima, K. M.; Kim, B. I.; Kim, C.; Kim, D. H.; Kim, D. J.; Kim, E.-J.; Kim, G. W.; Kim, H.-J.; Kim, M.; Kim, Y.-J.; Kim, Y. K.; Kimelman, B.; Kinney, E.; Kistenev, E.; Kitamura, R.; Klatsky, J.; Kleinjan, D.; Kline, P.; Koblesky, T.; Kofarago, M.; Komkov, B.; Koster, J.; Kotchetkov, D.; Kotov, D.; Krizek, F.; Kurita, K.; Kurosawa, M.; Kwon, Y.; Kyle, G. S.; Lacey, R.; Lai, Y. S.; Lajoie, J. G.; Lebedev, A.; Lee, D. M.; Lee, G. H.; Lee, J.; Lee, K. B.; Lee, K. S.; Lee, S.; Lee, S. H.; Lee, S. R.; Leitch, M. J.; Leite, M. A. L.; Leitgab, M.; Lewis, B.; Li, X.; Lim, S. H.; Linden Levy, L. A.; Liu, M. X.; Lynch, D.; Maguire, C. F.; Makdisi, Y. I.; Makek, M.; Manion, A.; Manko, V. I.; Mannel, E.; Maruyama, T.; McCumber, M.; McGaughey, P. L.; McGlinchey, D.; McKinney, C.; Meles, A.; Mendoza, M.; Meredith, B.; Miake, Y.; Mibe, T.; Midori, J.; Mignerey, A. C.; Miller, A. J.; Milov, A.; Mishra, D. K.; Mitchell, J. T.; Miyasaka, S.; Mizuno, S.; Mohanty, A. K.; Mohapatra, S.; Montuenga, P.; Moon, H. J.; Moon, T.; Morrison, D. P.; Moskowitz, M.; Moukhanova, T. V.; Murakami, T.; Murata, J.; Mwai, A.; Nagae, T.; Nagamiya, S.; Nagashima, K.; Nagle, J. L.; Nagy, M. I.; Nakagawa, I.; Nakagomi, H.; Nakamiya, Y.; Nakamura, K. R.; Nakamura, T.; Nakano, K.; Nattrass, C.; Netrakanti, P. K.; Nihashi, M.; Niida, T.; Nishimura, S.; Nouicer, R.; Novák, T.; Novitzky, N.; Nukariya, A.; Nyanin, A. S.; Obayashi, H.; O'Brien, E.; Ogilvie, C. A.; Oide, H.; Okada, K.; Orjuela Koop, J. D.; Osborn, J. D.; Oskarsson, A.; Ozaki, H.; Ozawa, K.; Pak, R.; Pantuev, V.; Papavassiliou, V.; Park, I. H.; Park, J. S.; Park, S.; Park, S. K.; Pate, S. F.; Patel, L.; Patel, M.; Pei, H.; Peng, J.-C.; Perepelitsa, D. V.; Perera, G. D. N.; Peressounko, D. Yu.; Perry, J.; Petti, R.; Pinkenburg, C.; Pinson, R.; Pisani, R. P.; Purschke, M. L.; Qu, H.; Rak, J.; Ramson, B. J.; Ravinovich, I.; Read, K. F.; Reynolds, D.; Riabov, V.; Riabov, Y.; Richardson, E.; Rinn, T.; Riveli, N.; Roach, D.; Roche, G.; Rolnick, S. D.; Rosati, M.; Rowan, Z.; Rubin, J. G.; Ryu, M. S.; Sahlmueller, B.; Saito, N.; Sakaguchi, T.; Sako, H.; Samsonov, V.; Sarsour, M.; Sato, S.; Sawada, S.; Schaefer, B.; Schmoll, B. K.; Sedgwick, K.; Seele, J.; Seidl, R.; Sekiguchi, Y.; Sen, A.; Seto, R.; Sett, P.; Sexton, A.; Sharma, D.; Shaver, A.; Shein, I.; Shibata, T.-A.; Shigaki, K.; Shimomura, M.; Shoji, K.; Shukla, P.; Sickles, A.; Silva, C. L.; Silvermyr, D.; Sim, K. S.; Singh, B. K.; Singh, C. P.; Singh, V.; Skolnik, M.; Slunečka, M.; Snowball, M.; Solano, S.; Soltz, R. A.; Sondheim, W. E.; Sorensen, S. P.; Sourikova, I. V.; Stankus, P. W.; Steinberg, P.; Stenlund, E.; Stepanov, M.; Ster, A.; Stoll, S. P.; Stone, M. R.; Sugitate, T.; Sukhanov, A.; Sumita, T.; Sun, J.; Sziklai, J.; Takagui, E. M.; Takahara, A.; Taketani, A.; Tanaka, Y.; Taneja, S.; Tanida, K.; Tannenbaum, M. J.; Tarafdar, S.; Taranenko, A.; Tennant, E.; Tieulent, R.; Timilsina, A.; Todoroki, T.; Tomášek, M.; Torii, H.; Towell, C. L.; Towell, M.; Towell, R.; Towell, R. S.; Tserruya, I.; Tsuchimoto, Y.; Vale, C.; van Hecke, H. W.; Vargyas, M.; Vazquez-Zambrano, E.; Veicht, A.; Velkovska, J.; Vértesi, R.; Virius, M.; Voas, B.; Vrba, V.; Vznuzdaev, E.; Wang, X. R.; Watanabe, D.; Watanabe, K.; Watanabe, Y.; Watanabe, Y. S.; Wei, F.; Whitaker, S.; White, A. S.; White, S. N.; Winter, D.; Wolin, S.; Woody, C. L.; Wysocki, M.; Xia, B.; Xue, L.; Yalcin, S.; Yamaguchi, Y. L.; Yanovich, A.; Ying, J.; Yokkaichi, S.; Yoo, J. H.; Yoon, I.; You, Z.; Younus, I.; Yu, H.; Yushmanov, I. E.; Zajc, W. A.; Zelenski, A.; Zhou, S.; Zou, L.; Phenix Collaboration

    2016-03-01

    We present midrapidity measurements from the PHENIX experiment of large parity-violating single-spin asymmetries of high transverse momentum electrons and positrons from W±/Z decays, produced in longitudinally polarized p +p collisions at center of mass energies of √{s }=500 and 510 GeV. These asymmetries allow direct access to the antiquark polarized parton distribution functions due to the parity-violating nature of the W -boson coupling to quarks and antiquarks. The results presented are based on data collected in 2011, 2012, and 2013 with an integrated luminosity of 240 pb-1 , which exceeds previous PHENIX published results by a factor of more than 27. These high Q2 data probe the parton structure of the proton at W mass scale and provide an important addition to our understanding of the antiquark parton helicity distribution functions at an intermediate Bjorken x value of roughly MW/√{s }=0.16 .

  6. Longitudinal impedance of RHIC

    SciTech Connect

    Blaskiewicz, M.; Brennan, J. M.; Mernick, K.

    2015-05-03

    The longitudinal impedance of the two RHIC rings has been measured using the effect of potential well distortion on longitudinal Schottky measurements. For the blue RHIC ring Im(Z/n) = 1.5±0.2Ω. For the yellow ring Im(Z/n) = 5.4±1Ω.

  7. Fiber Longitudinal Measurements for Predicting White Speck Contents of Dyed Cotton Fabrics

    USDA-ARS?s Scientific Manuscript database

    Fiber Image Analysis System (FIAS) was developed to provide an automatic method for measuring cotton maturity from fiber snippets or cross-sections . An uncombed cotton bundle is chopped and sprayed on a microscopic slide. The snippets are imaged sequentially on an microscope and measured with custo...

  8. Establishing Measurement Equivalence and Invariance in Longitudinal Data With Item Response Theory

    ERIC Educational Resources Information Center

    Meade, Adam W.; Lautenschlager, Gary J.; Hecht, Janet E.

    2005-01-01

    If measurement invariance does not hold over 2 or more measurement occasions, differences in observed scores are not directly interpretable. Golembiewski, Billingsley, and Yeager (1976) identified 2 types of psychometric differences over time as beta change and gamma change. Gamma change is a fundamental change in thinking about the nature of a…

  9. Establishing Measurement Equivalence and Invariance in Longitudinal Data With Item Response Theory

    ERIC Educational Resources Information Center

    Meade, Adam W.; Lautenschlager, Gary J.; Hecht, Janet E.

    2005-01-01

    If measurement invariance does not hold over 2 or more measurement occasions, differences in observed scores are not directly interpretable. Golembiewski, Billingsley, and Yeager (1976) identified 2 types of psychometric differences over time as beta change and gamma change. Gamma change is a fundamental change in thinking about the nature of a…

  10. Factor Structure and Measurement Invariance of a 10-Item Decisional Balance Scale: Longitudinal and Subgroup Examination within an Adult Diabetic Sample

    ERIC Educational Resources Information Center

    Pickering, Michael A.; Plotnikoff, Ronald C.

    2009-01-01

    This study explores the longitudinal and subgroup measurement properties of a 10-item, physical activity decisional balance scale, previously published by Plotnikoff, Blanchard, Hotz, and Rhodes (2001), within a diabetic sample of Canadian adults. Results indicated that a three-factor measurement model consistently improved model fit compared to…

  11. Factor Structure and Measurement Invariance of a 10-Item Decisional Balance Scale: Longitudinal and Subgroup Examination within an Adult Diabetic Sample

    ERIC Educational Resources Information Center

    Pickering, Michael A.; Plotnikoff, Ronald C.

    2009-01-01

    This study explores the longitudinal and subgroup measurement properties of a 10-item, physical activity decisional balance scale, previously published by Plotnikoff, Blanchard, Hotz, and Rhodes (2001), within a diabetic sample of Canadian adults. Results indicated that a three-factor measurement model consistently improved model fit compared to…

  12. A longitudinal study of the dietary practices of black and white girls 9 and 10 years old at enrollment: the NHLBI Growth and Health Study.

    PubMed

    McNutt, S W; Hu, Y; Schreiber, G B; Crawford, P B; Obarzanek, E; Mellin, L

    1997-01-01

    To determine whether there are racial differences in the frequency with which black and white girls engaged in eating practices commonly targeted for modification in weight reduction programs. This is part of the NHLBI Growth and Health Study, a longitudinal study of preadolescent girls designed to examine the factors associated with development of obesity, and its later effects on cardiovascular risk factors. Black and white girls ages 9-10 years at entry (n = 2,379) were recruited at three clinical sites. Racial differences were examined in 11 "weight-related" eating practices such as eating with TV, eating while doing homework, and skipping meals. Multiple logistic regression analyses were then conducted for each of the dependent variables. Black girls were more than twice as likely as white girls to frequently engage in the targeted weight-related eating practices. The odds of a study girl frequently engaging in most of these eating practices decreased with an increase in parents' income and education level. However, even when controlling for socioeconomic and demographic effects, black girls remained more likely to engage in these eating practices than white girls. For most of the behaviors, girls who frequently practiced a behavior had higher energy intakes compared to those who practiced it infrequently. The finding that black girls at an early age more frequently engage in eating practices associated with weight gain may have significant implications for obesity development. For both young black and white girls, early education efforts may be necessary in helping develop good eating habits. Since it appears that black girls have a higher risk of developing adverse weight-related eating practices, culturally appropriate education materials may be required.

  13. Challenges in longitudinal measurements with HR-pQCT: evaluation of a 3D registration method to improve bone microarchitecture and strength measurement reproducibility.

    PubMed

    Ellouz, Rafaa; Chapurlat, Roland; van Rietbergen, Bert; Christen, Patrik; Pialat, Jean-Baptiste; Boutroy, Stephanie

    2014-06-01

    Definition of identical regions between repeated computed tomography (CT) scans is a key factor to monitor changes in bone microarchitecture. In longitudinal studies, accurate determination of the volume of interest (VOI), using three dimensional (3D) registration may improve precision. Therefore, the aim of our study was to investigate the short-term reproducibility of bone geometry, density, microstructure and biomechanical parameters assessed by HR-pQCT and micro-finite element (μFE) derived analyses, using the cross-sectional area (CSA) registration method in comparison with the use of 3D registration, to find overlapping regions between scans. Fifteen healthy individuals (aged 21-47 years) underwent 3 separate scans at the distal radius and tibia, within a one-month interval. Reproducibility was assessed after double contouring the cortical compartment and after applying three different methods to determine the common region between repeated scans: (i) the VOI was determined with no registration, i.e., on 110 slices, (ii) the VOI was determined after CSA-based registration, and (iii) the VOI was determined after 3D registration. Both pre- and post-registration short-term reproducibility for each subject was determined. With no registration, CVrms of geometry parameters ranged from 0.5 to 3.7%, showing a slight variation in the CSA between scans. When the CSA registration method was employed, the variability of geometry (CVrms<1.8%) and density parameters (CVrms<1.8%), was better than that obtained without registration. By removing the effect of repositioning, the 3D registration further improved the reproducibility of cortical bone measurements compared to other methods. Indeed, significant improvements were found for cortical geometry and microstructure measurements (CVrms ranged from 0.4% to 10.7% at both sites; p<0.05), whereas the impact on trabecular bone measurements was restricted to its geometry parameter. The repositioning error was significantly

  14. Accelerated failure time model for case-cohort design with longitudinal covariates subject to measurement error and detection limits.

    PubMed

    Dong, Xinxin; Kong, Lan; Wahed, Abdus S

    2016-04-15

    Biomarkers are often measured over time in epidemiological studies and clinical trials for better understanding of the mechanism of diseases. In large cohort studies, case-cohort sampling provides a cost effective method to collect expensive biomarker data for revealing the relationship between biomarker trajectories and time to event. However, biomarker measurements are often limited by the sensitivity and precision of a given assay, resulting in data that are censored at detection limits and prone to measurement errors. Additionally, the occurrence of an event of interest may preclude biomarkers from being further evaluated. Inappropriate handling of these types of data can lead to biased conclusions. Under a classical case cohort design, we propose a modified likelihood-based approach to accommodate these special features of longitudinal biomarker measurements in the accelerated failure time models. The maximum likelihood estimators based on the full likelihood function are obtained by Gaussian quadrature method. We evaluate the performance of our case-cohort estimator and compare its relative efficiency to the full cohort estimator through simulation studies. The proposed method is further illustrated using the data from a biomarker study of sepsis among patients with community acquired pneumonia.

  15. A longitudinal study of outcome measures for children receiving early intervention services.

    PubMed

    Eigsti, Heidi Johnson; Chandler, Lynette; Robinson, Cordelia; Bodkin, Amy Winters

    2010-01-01

    The purpose of this study was to compare the Pediatric Evaluation of Disability Inventory (PEDI) and the Mullen Scales of Early Learning (MSEL) as measures of change in children who received early intervention services. Thirty-four children were stratified into 2 groups according to the presence of gross motor delay. The PEDI and MSEL were administered 3 times: at an average age of 18, 31, and 53 months of age. Data were analyzed using a repeated-measures multivariate analysis of variance. The findings suggest that PEDI Functional Skills Scaled Scores were capable of measuring change in both groups of children. The standard scores on the PEDI Functional Skills Social Scale were found to be more sensitive to change than the MSEL Receptive and Expressive Language scores for children with motor delays. Using PEDI scaled scores may be an effective strategy for measuring change in children receiving early intervention services.

  16. Longitudinal prediction of child outcomes from differing measures of parenting in a low-income sample.

    PubMed

    Zaslow, Martha J; Weinfield, Nancy S; Gallagher, Megan; Hair, Elizabeth C; Ogawa, John R; Egeland, Byron; Tabors, Patton O; De Temple, Jeanne M

    2006-01-01

    This study examined predictions from preschool parenting measures to middle childhood cognitive and socioemotional child outcomes to explore whether parenting assessment methodologies that require more time, training, and expense yield better predictions of child outcomes than less intensive methodologies. Mother-child dyads (N = 278) in low-income African American families were assessed when the child was in preschool, using maternal report, the Home Observation for Measurement of the Environment-Short Form (P. Baker & F. Mott, 1989; R. Bradley & B. Caldwell, 1984), and structured observational measures of parenting. Child outcomes reported by children, mothers, teachers, and direct assessment were collected 4 years later. All parenting methodologies showed some predictive value; however, observational parenting measures showed the strongest and most consistent predictions of child outcomes. Copyright 2006 APA, all rights reserved.

  17. Measuring the Strategic Value of the Armed Forces Health Longitudinal Technology Application (AHLTA)

    DTIC Science & Technology

    2008-01-01

    purchased care). In January 2004, the MHS’s Clinical Information Technology Program Office (CITPO) began implementation of the Armed Forces Health ...2) reviewed the literature on the measured iv Measuring the Strategic Value of AHLTA benefits of health information technology , (3) consulted...grateful to Michael Din- neen and Paul Tibbits for sharing their insights on the role of health information technology in the strategic transformation

  18. Variability in baseline laboratory measurements of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil)

    PubMed Central

    Ladwig, R.; Vigo, A.; Fedeli, L.M.G.; Chambless, L.E.; Bensenor, I.; Schmidt, M.I.; Vidigal, P.G.; Castilhos, C.D.; Duncan, B.B.

    2016-01-01

    Multi-center epidemiological studies must ascertain that their measurements are accurate and reliable. For laboratory measurements, reliability can be assessed through investigation of reproducibility of measurements in the same individual. In this paper, we present results from the quality control analysis of the baseline laboratory measurements from the ELSA-Brasil study. The study enrolled 15,105 civil servants at 6 research centers in 3 regions of Brazil between 2008–2010, with multiple biochemical analytes being measured at a central laboratory. Quality control was ascertained through standard laboratory evaluation of intra- and inter-assay variability and test-retest analysis in a subset of randomly chosen participants. An additional sample of urine or blood was collected from these participants, and these samples were handled in the same manner as the original ones, locally and at the central laboratory. Reliability was assessed with the intraclass correlation coefficient (ICC), estimated through a random effects model. Coefficients of variation (CV) and Bland-Altman plots were additionally used to assess measurement variability. Laboratory intra and inter-assay CVs varied from 0.86% to 7.77%. From test-retest analyses, the ICCs were high for the majority of the analytes. Notably lower ICCs were observed for serum sodium (ICC=0.50; 95%CI=0.31–0.65) and serum potassium (ICC=0.73; 95%CI=0.60–0.83), due to the small biological range of these analytes. The CVs ranged from 1 to 14%. The Bland-Altman plots confirmed these results. The quality control analyses showed that the collection, processing and measurement protocols utilized in the ELSA-Brasil produced reliable biochemical measurements. PMID:27533768

  19. Variability in baseline laboratory measurements of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil).

    PubMed

    Ladwig, R; Vigo, A; Fedeli, L M G; Chambless, L E; Bensenor, I; Schmidt, M I; Vidigal, P G; Castilhos, C D; Duncan, B B

    2016-08-01

    Multi-center epidemiological studies must ascertain that their measurements are accurate and reliable. For laboratory measurements, reliability can be assessed through investigation of reproducibility of measurements in the same individual. In this paper, we present results from the quality control analysis of the baseline laboratory measurements from the ELSA-Brasil study. The study enrolled 15,105 civil servants at 6 research centers in 3 regions of Brazil between 2008-2010, with multiple biochemical analytes being measured at a central laboratory. Quality control was ascertained through standard laboratory evaluation of intra- and inter-assay variability and test-retest analysis in a subset of randomly chosen participants. An additional sample of urine or blood was collected from these participants, and these samples were handled in the same manner as the original ones, locally and at the central laboratory. Reliability was assessed with the intraclass correlation coefficient (ICC), estimated through a random effects model. Coefficients of variation (CV) and Bland-Altman plots were additionally used to assess measurement variability. Laboratory intra and inter-assay CVs varied from 0.86% to 7.77%. From test-retest analyses, the ICCs were high for the majority of the analytes. Notably lower ICCs were observed for serum sodium (ICC=0.50; 95%CI=0.31-0.65) and serum potassium (ICC=0.73; 95%CI=0.60-0.83), due to the small biological range of these analytes. The CVs ranged from 1 to 14%. The Bland-Altman plots confirmed these results. The quality control analyses showed that the collection, processing and measurement protocols utilized in the ELSA-Brasil produced reliable biochemical measurements.

  20. The Role of Sleep Disturbances in the Longitudinal Relationship Between Psychosocial Working Conditions, Measured by Work Demands and Support, and Depression

    PubMed Central

    Magnusson Hanson, Linda L.; Chungkham, Holendro Singh; Åkerstedt, Torbjörn; Westerlund, Hugo

    2014-01-01

    Study Objectives: Because work demands and lack of social support seem to be prospectively linked to sleep problems, and sleep problems are linked to depression, sleep problems may play a role in the relationship between these work characteristics and depressive symptoms. In order to shed more light on this relationship, the current study investigated whether disturbed sleep is a mediator in the longitudinal relationships between work demands, social support, and depression. Design: Longitudinal cohort study with repeated survey measures on four occasions. Setting: Swedish workforce. Participants: 2,017 working participants from the Swedish Longitudinal Occupational Survey of Health in 2006, 2008, 2010, and 2012. Measurements and results: Work demands (four items) and social support (six items) were assessed with the Demand Control Questionnaire, disturbed sleep (four items) with the Karolinska Sleep Questionnaire, and depressive symptoms with a brief subscale (six items) from the Symptom Checklist. Autoregressive longitudinal mediation models using structural equation modeling were tested. The work characteristics, and disturbed sleep, were found to be separately associated with depressive symptoms in subsequent waves. However, only demands were found to be longitudinally related to subsequent disturbed sleep. The longitudinal autoregressive models supported a weak mediating role of disturbed sleep in the relationship between demands and depressive symptoms (standardized beta 0.008, P < 0.001), but not between support and depressive symptoms. Conclusions: These results indicate that higher demands at work might cause an increase in depressive symptoms, in part, by increasing disturbed sleep, although the mediated effect was relatively small compared to the total effect. Citation: Magnusson Hanson LL, Chungkham HS, Åkerstedt T, Westerlund H. The role of sleep disturbances in the longitudinal relationship between psychosocial working conditions, measured by work

  1. The role of sleep disturbances in the longitudinal relationship between psychosocial working conditions, measured by work demands and support, and depression.

    PubMed

    Magnusson Hanson, Linda L; Chungkham, Holendro Singh; Åkerstedt, Torbjörn; Westerlund, Hugo

    2014-12-01

    Because work demands and lack of social support seem to be prospectively linked to sleep problems, and sleep problems are linked to depression, sleep problems may play a role in the relationship between these work characteristics and depressive symptoms. In order to shed more light on this relationship, the current study investigated whether disturbed sleep is a mediator in the longitudinal relationships between work demands, social support, and depression. Longitudinal cohort study with repeated survey measures on four occasions. Swedish workforce. 2,017 working participants from the Swedish Longitudinal Occupational Survey of Health in 2006, 2008, 2010, and 2012. Work demands (four items) and social support (six items) were assessed with the Demand Control Questionnaire, disturbed sleep (four items) with the Karolinska Sleep Questionnaire, and depressive symptoms with a brief subscale (six items) from the Symptom Checklist. Autoregressive longitudinal mediation models using structural equation modeling were tested. The work characteristics, and disturbed sleep, were found to be separately associated with depressive symptoms in subsequent waves. However, only demands were found to be longitudinally related to subsequent disturbed sleep. The longitudinal autoregressive models supported a weak mediating role of disturbed sleep in the relationship between demands and depressive symptoms (standardized beta 0.008, P < 0.001), but not between support and depressive symptoms. These results indicate that higher demands at work might cause an increase in depressive symptoms, in part, by increasing disturbed sleep, although the mediated effect was relatively small compared to the total effect. © 2014 Associated Professional Sleep Societies, LLC.

  2. Measurement of the longitudinal, transverse, and longitudinal-transverse structure functions in the {sup 2}H({ital e},{ital e}{prime}{ital p}){ital n} reaction

    SciTech Connect

    Jordan, D.; McIlvain, T.; Alarcon, R.; Beck, R.; Bertozzi, W.; Bhushan, V.; Boeglin, W.; Chen, J.P.; Dale, D.; Dodson, G.; Dolfini, S.; Dow, K.; Dzengeleski, J.; Epstein, M.B.; Farkhondeh, M.; Gilad, S.; Goergen, J.; Holtrop, M.; Joo, K.; Kelsey, J.; Kim, W.; Laszewski, R.; Lourie, R.; Mandeville, J.; Margaziotis, D.; Martinez, D.; Miskimen, R.; Papanicolas, C.N.; Penn, S.; Sapp, W.; Sarty, A.J.; Tieger, D.; Tschalaer, C.; Turchinetz, W.; Warren, G.; Weinstein, L.; Williamson, S. |||||

    1996-03-01

    We have separated the longitudinal ({ital f}{sub 00}), transverse ({ital f}{sub 11}), and longitudinal-transverse interference ({ital f}{sub 01}) structure functions in the {sup 2}H({ital e},{ital e}{prime}{ital p}){ital n} reaction at {ital q}{searrow}{parallel}{approx_equal} 400 MeV/{ital c} and {omega}{approx_equal}110 MeV. A nonrelativistic calculation which includes effects due to final state interactions, meson exchange currents, and isobar configurations agrees with the measured {ital f}{sub 11} and {ital f}{sub 01} but overpredicts {ital f}{sub 00} by 25{percent} (2{sigma}). The data are also compared to the results of previous structure function measurements. {copyright} {ital 1996 The American Physical Society.}

  3. Longitudinal qualitative study describing family physicians’ experiences with attempting to integrate physical activity prescriptions in their practice: ‘It’s not easy to change habits’

    PubMed Central

    Bélanger, Mathieu; Phillips, Emily Wolfe; O’Rielly, Connor; Mallet, Bertin; Aubé, Shane; Doucet, Marylène; Couturier, Jonathan; Mallet, Maxime; Martin, Jessica; Gaudet, Christine; Murphy, Nathalie; Brunet, Jennifer

    2017-01-01

    Objective Physical activity (PA) prescriptions provided by family physicians can promote PA participation among patients, but few physicians regularly write PA prescriptions. The objective of this study was to describe family physicians’ experiences of trying to implement written PA prescriptions into their practice. Design Longitudinal qualitative study where participants were interviewed four times during a 12-month period. After the first interview, they were provided with PA prescription pads. Data were analysed using thematic analysis. Setting Family medicine clinics in New Brunswick, Canada. Participants Family physicians (n=11) with no prior experience writing PA prescriptions, but who expressed interest in changing their practice to implement written PA prescriptions. Results Initially, participants exhibited confidence in their ability to write PA prescriptions in the future and intended to write prescriptions. However, data from the follow-up interviews indicated that the rate of implementation was lower than anticipated by participants and prescriptions were not part of their regular practice. Two themes emerged as factors explaining the gap between their intentions and behaviours: (1) uncertainty about the effectiveness of written PA prescription, and (2) practical concerns (eg, changing well-established habits, time constraints, systemic institutional barriers). Conclusion It may be effective to increase awareness among family physicians about the effectiveness of writing PA prescriptions and address barriers related to how their practice is organised in order to promote written PA prescription rates. PMID:28710228

  4. An electrical load measurements dataset of United Kingdom households from a two-year longitudinal study

    PubMed Central

    Murray, David; Stankovic, Lina; Stankovic, Vladimir

    2017-01-01

    Smart meter roll-outs provide easy access to granular meter measurements, enabling advanced energy services, ranging from demand response measures, tailored energy feedback and smart home/building automation. To design such services, train and validate models, access to data that resembles what is expected of smart meters, collected in a real-world setting, is necessary. The REFIT electrical load measurements dataset described in this paper includes whole house aggregate loads and nine individual appliance measurements at 8-second intervals per house, collected continuously over a period of two years from 20 houses. During monitoring, the occupants were conducting their usual routines. At the time of publishing, the dataset has the largest number of houses monitored in the United Kingdom at less than 1-minute intervals over a period greater than one year. The dataset comprises 1,194,958,790 readings, that represent over 250,000 monitored appliance uses. The data is accessible in an easy-to-use comma-separated format, is time-stamped and cleaned to remove invalid measurements, correctly label appliance data and fill in small gaps of missing data. PMID:28055033

  5. Longitudinal Transient Elastography Measurements Used in Follow-up for Patients with Cystic Fibrosis.

    PubMed

    Van Biervliet, Stephanie; Verdievel, Hugo; Vande Velde, Saskia; De Bruyne, Ruth; De Looze, Danny; Verhelst, Xavier; Geerts, Anja; Robberecht, Eddy; Van Vlierberghe, Hans

    2016-04-01

    Cystic fibrosis-related liver disease (CFLD) is diagnosed using a combination of criteria. Transient elastography (TE), an ultrasonographic method to evaluate liver stiffness, can differentiate patients with and without liver disease. This retrospective study (2007-2013) aimed to detect developing CFLD using consequent TE measurements. All cystic fibrosis patients with TE measurements between 2007 and 2013 (n = 150, median age 17 (9-24) y) were included, of which 118 had a median of three (range, 2-4) measurements with an interval of 1 (1-2) y. Twenty (14%) had CFLD at the first TE measurement; five (3%) developed CFLD during follow-up. The median TE value in CFLD was 14 kPa (8.7-32.2) compared with 5.3 (4.9-5.7) in cystic fibrosis patients without liver disease (CFnoLD; p = 0.0001). In CFnoLD, TE was correlated with age (p = 0.031). A TE result >6.8 kPa had a sensitivity of 91.5% and a specificity of 91.7% in predicting CFLD, according to the receiver operating characteristics analysis. It also has a positive predictive value of 88.6% and a negative predictive value of 86.9%, increasing to 91.7% and 98%, respectively, in patients at risk (<14 y) for developing CFLD. Patients with developing CFLD had progressively increasing consecutive TE measurements.

  6. An electrical load measurements dataset of United Kingdom households from a two-year longitudinal study.

    PubMed

    Murray, David; Stankovic, Lina; Stankovic, Vladimir

    2017-01-05

    Smart meter roll-outs provide easy access to granular meter measurements, enabling advanced energy services, ranging from demand response measures, tailored energy feedback and smart home/building automation. To design such services, train and validate models, access to data that resembles what is expected of smart meters, collected in a real-world setting, is necessary. The REFIT electrical load measurements dataset described in this paper includes whole house aggregate loads and nine individual appliance measurements at 8-second intervals per house, collected continuously over a period of two years from 20 houses. During monitoring, the occupants were conducting their usual routines. At the time of publishing, the dataset has the largest number of houses monitored in the United Kingdom at less than 1-minute intervals over a period greater than one year. The dataset comprises 1,194,958,790 readings, that represent over 250,000 monitored appliance uses. The data is accessible in an easy-to-use comma-separated format, is time-stamped and cleaned to remove invalid measurements, correctly label appliance data and fill in small gaps of missing data.

  7. An electrical load measurements dataset of United Kingdom households from a two-year longitudinal study

    NASA Astrophysics Data System (ADS)

    Murray, David; Stankovic, Lina; Stankovic, Vladimir

    2017-01-01

    Smart meter roll-outs provide easy access to granular meter measurements, enabling advanced energy services, ranging from demand response measures, tailored energy feedback and smart home/building automation. To design such services, train and validate models, access to data that resembles what is expected of smart meters, collected in a real-world setting, is necessary. The REFIT electrical load measurements dataset described in this paper includes whole house aggregate loads and nine individual appliance measurements at 8-second intervals per house, collected continuously over a period of two years from 20 houses. During monitoring, the occupants were conducting their usual routines. At the time of publishing, the dataset has the largest number of houses monitored in the United Kingdom at less than 1-minute intervals over a period greater than one year. The dataset comprises 1,194,958,790 readings, that represent over 250,000 monitored appliance uses. The data is accessible in an easy-to-use comma-separated format, is time-stamped and cleaned to remove invalid measurements, correctly label appliance data and fill in small gaps of missing data.

  8. Longitudinal bunch length measurement of RFQ beam using in-house developed detector system

    NASA Astrophysics Data System (ADS)

    Pandey, H. K.; Dechoudhury, S.; Bhattacharyya, T. K.; Chakrabarti, A.

    2017-09-01

    We report here the bunch width measurement of 98keV/u ion beam accelerated through a 3.4 m long 37.8 MHz Radio Frequency Quadruple (RFQ) linac using a minimally interceptive approach. The detector system for this measurement has been indigenously developed and is based on secondary electron emission from tungsten filament on being hit by ion beam, followed by a capacitive loaded helical resonator cavity. A Channeltron Electron Multiplier (CEM) detector is used for detection of electrons. The design, development and optimization of various parameters of bunch width detector system along with its deflector cavity applicable in the low frequency regime (few tens of MHz) have been discussed. The measured bunch profile of accelerated Nitrogen beam from RFQ is in close agreement with the estimated profile obtained via simulation.

  9. Factor structure and longitudinal measurement invariance of PHQ-9 for specialist mental health care patients with persistent major depressive disorder: Exploratory Structural Equation Modelling.

    PubMed

    Guo, Boliang; Kaylor-Hughes, Catherine; Garland, Anne; Nixon, Neil; Sweeney, Tim; Simpson, Sandra; Dalgleish, Tim; Ramana, Rajini; Yang, Min; Morriss, Richard

    2017-09-01

    The Patient Health Questionnaire-9 (PHQ-9) is a widely used instrument for measuring levels of depression in patients in clinical practice and academic research; its factor structure has been investigated in various samples, with limited evidence of measurement equivalence/invariance (ME/I) but not in patients with more severe depression of long duration. This study aims to explore the factor structure of the PHQ-9 and the ME/I between treatment groups over time for these patients. 187 secondary care patients with persistent major depressive disorder (PMDD) were recruited to a randomised controlled trial (RCT) with allocation to either a specialist depression team arm or a general mental health arm; their PHQ-9 score was measured at baseline, 3, 6, 9 and 12 months. Exploratory Structural Equational Modelling (ESEM) was performed to examine the factor structure for this specific patient group. ME/I between treatment arm at and across follow-up time were further explored by means of multiple-group ESEM approach using the best-fitted factor structure. A two-factor structure was evidenced (somatic and affective factor). This two-factor structure had strong factorial invariance between the treatment groups at and across follow up times. Participants were largely white British in a RCT with 40% attrition potentially limiting the study's generalisability. Not all two-factor modelling criteria were met at every time-point. PHQ-9 has a two-factor structure for PMDD patients, with strong measurement invariance between treatment groups at and across follow-up time, demonstrating its validity for RCTs and prospective longitudinal studies in chronic moderate to severe depression. Copyright © 2017. Published by Elsevier B.V.

  10. Individual differences in children's global motion sensitivity correlate with TBSS-based measures of the superior longitudinal fasciculus.

    PubMed

    Braddick, Oliver; Atkinson, Janette; Akshoomoff, Natacha; Newman, Erik; Curley, Lauren B; Gonzalez, Marybel Robledo; Brown, Timothy; Dale, Anders; Jernigan, Terry

    2016-12-16

    Reduced global motion sensitivity, relative to global static form sensitivity, has been found in children with many neurodevelopmental disorders, leading to the "dorsal stream vulnerability" hypothesis (Braddick et al., 2003). Individual differences in typically developing children's global motion thresholds have been shown to be associated with variations in specific parietal cortical areas (Braddick et al., 2016). Here, in 125 children aged 5-12years, we relate individual differences in global motion and form coherence thresholds to fractional anisotropy (FA) in the superior longitudinal fasciculus (SLF), a major fibre tract communicating between parietal lobe and anterior cortical areas. We find a positive correlation between FA of the right SLF and individual children's sensitivity to global motion coherence, while FA of the left SLF shows a negative correlation. Further analysis of parietal cortical area data shows that this is also asymmetrical, showing a stronger association with global motion sensitivity in the left hemisphere. None of these associations hold for an analogous measure of global form sensitivity. We conclude that a complex pattern of structural asymmetry, including the parietal lobe and the superior longitudinal fasciculus, is specifically linked to the development of sensitivity to global visual motion. This pattern suggests that individual differences in motion sensitivity are primarily linked to parietal brain areas interacting with frontal systems in making decisions on integrated motion signals, rather than in the extra-striate visual areas that perform the initial integration. The basis of motion processing deficits in neurodevelopmental disorders may depend on these same structures. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  11. Increasing the sensitivity of NMR diffusion measurements by paramagnetic longitudinal relaxation enhancement, with application to ribosome–nascent chain complexes

    PubMed Central

    Cassaignau, Anaïs M. E.; Cabrita, Lisa D.

    2016-01-01

    The translational diffusion of macromolecules can be examined non-invasively by stimulated echo (STE) NMR experiments to accurately determine their molecular sizes. These measurements can be important probes of intermolecular interactions and protein folding and unfolding, and are crucial in monitoring the integrity of large macromolecular assemblies such as ribosome–nascent chain complexes (RNCs). However, NMR studies of these complexes can be severely constrained by their slow tumbling, low solubility (with maximum concentrations of up to 10 μM), and short lifetimes resulting in weak signal, and therefore continuing improvements in experimental sensitivity are essential. Here we explore the use of the paramagnetic longitudinal relaxation enhancement (PLRE) agent NiDO2A on the sensitivity of 15N XSTE and SORDID heteronuclear STE experiments, which can be used to monitor the integrity of these unstable complexes. We exploit the dependence of the PLRE effect on the gyromagnetic ratio and electronic relaxation time to accelerate recovery of 1H magnetization without adversely affecting storage on Nz during diffusion delays or introducing significant transverse relaxation line broadening. By applying the longitudinal relaxation-optimized SORDID pulse sequence together with NiDO2A to 70S Escherichia coli ribosomes and RNCs, NMR diffusion sensitivity enhancements of up to 4.5-fold relative to XSTE are achieved, alongside ~1.9-fold improvements in two-dimensional NMR sensitivity, without compromising the sample integrity. We anticipate these results will significantly advance the use of NMR to probe dynamic regions of ribosomes and other large, unstable macromolecular assemblies. PMID:26253948

  12. Quantitative measurement of blaCMY-2 in a longitudinal observational study of dairy cattle treated with ceftiofur.

    PubMed

    Boyer, Tim C; Singer, Randall S

    2012-11-01

    There is concern that a relationship exists between antibiotic use in livestock production and the emergence, spread, and persistence of antibiotic resistance. It is important to understand the impact that therapeutic doses of antibiotics for treatment of disease have on resistance because disease treatment typically involves higher doses of antibiotic over short time spans. Absolute quantities of the antibiotic resistance gene bla(CMY-2) were measured by real-time quantitative polymerase chain reaction (qPCR) in the bacterial community DNA of fecal samples from dairy cattle that were given a 5-day course of ceftiofur and untreated cattle during a longitudinal, observational study. A hierarchical linear model that accounts for left-censored data and repeated measures was used to estimate group means of bla(CMY-2) from the qPCR data. Ceftiofur-treated animals had significantly higher mean quantities of bla(CMY-2) than untreated animals during treatment. On the first day post-treatment, mean quantities of bla(CMY-2) returned to pre-treatment levels and remained low in both groups for the remainder of the study. The use of qPCR to measure bla(CMY-2) quantities provided evidence that the burden of resistance in treated animals may have increased temporarily, a result that was not evident when using only cultivation-based methods of testing for resistance.

  13. Knowledge, Attitude, and Practice of Pregnant Women regarding Oral Health Status and Treatment Needs following Oral Health Education in Pune District of Maharashtra: A Longitudinal Hospital-based Study.

    PubMed

    Chawla, Roshani M; Shetiya, Sahana H; Agarwal, Deepti R; Mitra, Pranjan; Bomble, Nikhil A; Narayana, D Satya

    2017-05-01

    Pregnancy is a natural process that may create some changes in different parts of the body including the oral cavity. These changes will lead to oral diseases if enough and timely care of oral cavity is not taken. Women may experience increased gingivitis or pregnancy gingivitis beginning in the second or third month of pregnancy that increases in severity throughout the duration of pregnancy. To motivate the patient toward oral health and implement the needed prophylactic measures, a longitudinal study was planned to observe the effect of oral health education during pregnancy on knowledge, attitude, practice, oral health status, and treatment needs (TNs) of pregnant women belonging to different socioeconomic groups. A longitudinal study was conducted among 112 pregnant women belonging to different socioeconomic groups to assess the effect of oral health education on knowledge, attitude, practice, oral health status, and TNs. The demographic details, knowledge, attitude, and practice of pregnant women, and oral health status were collected through a predesigned questionnaire by a principal investigator through an interview. Oral health examination was carried out to assess oral health status using revised World Health Organization Proforma 1997, and oral health education was given through PowerPoint presentation to the participants in local language, i.e., Marathi, after collecting the baseline data. Reinforcement of oral health education and blanket referral was done at 14th week, and follow-up data were collected at 28th week of gestation. The demographic details, such as age, sex, education, occupation, income, and the questions based on knowledge, attitude, and practice among participants were analyzed using number, percentage, and mean. At baseline, knowledge was limited, attitude was positive, while the practice was poor regarding oral health care during pregnancy in pregnant women belonging to different socioeconomic groups. After oral health education and

  14. Measuring Knowledge Integration Learning of Energy Topics: A Two-Year Longitudinal Study

    ERIC Educational Resources Information Center

    Liu, Ou Lydia; Ryoo, Kihyun; Linn, Marcia C.; Sato, Elissa; Svihla, Vanessa

    2015-01-01

    Although researchers call for inquiry learning in science, science assessments rarely capture the impact of inquiry instruction. This paper reports on the development and validation of assessments designed to measure middle-school students' progress in gaining integrated understanding of energy while studying an inquiry-oriented curriculum. The…

  15. Measuring Meaningful Learning in the Undergraduate General Chemistry and Organic Chemistry Laboratories: A Longitudinal Study

    ERIC Educational Resources Information Center

    Galloway, Kelli R.; Bretz, Stacey Lowery

    2015-01-01

    Understanding how students learn in the undergraduate chemistry teaching laboratory is an essential component to developing evidence-based laboratory curricula. The Meaningful Learning in the Laboratory Instrument (MLLI) was developed to measure students' cognitive and affective expectations and experiences for learning in the chemistry…

  16. Longitudinal Study of a Novel, Performance-based Measure of Everyday Functional Competence

    DTIC Science & Technology

    2014-04-01

    epilepsy , schizophrenia, stroke, and AD, there appears to be a paradox. One explanation for this discrepancy might be that the measures commonly...Davies P, Goldberg TE. Development of an UPSA short form for use in Mild Cognitive Impairment and Alzheimer’s disease. Am J Geriatric Psychiatry. 2011

  17. Measuring Knowledge Integration Learning of Energy Topics: A Two-Year Longitudinal Study

    ERIC Educational Resources Information Center

    Liu, Ou Lydia; Ryoo, Kihyun; Linn, Marcia C.; Sato, Elissa; Svihla, Vanessa

    2015-01-01

    Although researchers call for inquiry learning in science, science assessments rarely capture the impact of inquiry instruction. This paper reports on the development and validation of assessments designed to measure middle-school students' progress in gaining integrated understanding of energy while studying an inquiry-oriented curriculum. The…

  18. Longitudinal Approaches to Stages of Change Measurement: Effects on Cognitive and Behavioral Physical Activity Factors

    ERIC Educational Resources Information Center

    Parker, Philip D.; Martin, Andrew J.; Martinez, Carissa; Marsh, Herbert W.; Jackson, Susan

    2010-01-01

    The transition from school to further education and work is one of immense change that impacts physical activity attitudes and engagement in adulthood. The Stages of Change (SOC) model, which resides under the transtheoretical framework, has been proposed as one way to measure and evaluate physical activity uptake and maintenance. The current…

  19. Dew measurements along a longitudinal sand dune transect, Negev Desert, Israel.

    PubMed

    Jacobs, A F; Heusinkveld, B G; Berkowicz, S M

    2000-03-01

    In a desert environment dew can serve as an important source of moisture for plants, biological crusts, insects and small animals. A measurement programme was carried out within a sand dune belt situated in the northwestern Negev desert, Israel, to measure daily amounts of dew deposition as well as micro-meteorological conditions during the dew formation and early-morning drying process. Dew quantities were measured by micro-lysimeters along a 200-m transect as well as by the eddy-correlation technique at a reference location. A simple physical model was constructed to simulate the dew deposition process as well as early-morning drying for the interdune area and the north- and south-facing dune slopes. Measurements carried out during September and October 1997 showed that the daily amounts of dew ranged between 0.1 mm/night and 0.3 mm/night within the interdune area. On the slopes, the amounts of dew were about 50% lower. Simulated results agreed well with the field data.

  20. Longitudinal Approaches to Stages of Change Measurement: Effects on Cognitive and Behavioral Physical Activity Factors

    ERIC Educational Resources Information Center

    Parker, Philip D.; Martin, Andrew J.; Martinez, Carissa; Marsh, Herbert W.; Jackson, Susan

    2010-01-01

    The transition from school to further education and work is one of immense change that impacts physical activity attitudes and engagement in adulthood. The Stages of Change (SOC) model, which resides under the transtheoretical framework, has been proposed as one way to measure and evaluate physical activity uptake and maintenance. The current…

  1. Longitudinal Prediction of Child Outcomes from Differing Measures of Parenting in a Low-Income Sample

    ERIC Educational Resources Information Center

    Zaslow, Martha J.; Weinfield, Nancy S.; Gallagher, Megan; Hair, Elizabeth C.; Ogawa, John R.; Egeland, Byron; Tabors, Patton O.; De Temple, Jeanne M.

    2006-01-01

    This study examined predictions from preschool parenting measures to middle childhood cognitive and socioemotional child outcomes to explore whether parenting assessment methodologies that require more time, training, and expense yield better predictions of child outcomes than less intensive methodologies. Mother-child dyads (N=278) in low-income…

  2. Longitudinal Prediction of Child Outcomes from Differing Measures of Parenting in a Low-Income Sample

    ERIC Educational Resources Information Center

    Zaslow, Martha J.; Weinfield, Nancy S.; Gallagher, Megan; Hair, Elizabeth C.; Ogawa, John R.; Egeland, Byron; Tabors, Patton O.; De Temple, Jeanne M.

    2006-01-01

    This study examined predictions from preschool parenting measures to middle childhood cognitive and socioemotional child outcomes to explore whether parenting assessment methodologies that require more time, training, and expense yield better predictions of child outcomes than less intensive methodologies. Mother-child dyads (N=278) in low-income…

  3. Measuring Meaningful Learning in the Undergraduate General Chemistry and Organic Chemistry Laboratories: A Longitudinal Study

    ERIC Educational Resources Information Center

    Galloway, Kelli R.; Bretz, Stacey Lowery

    2015-01-01

    Understanding how students learn in the undergraduate chemistry teaching laboratory is an essential component to developing evidence-based laboratory curricula. The Meaningful Learning in the Laboratory Instrument (MLLI) was developed to measure students' cognitive and affective expectations and experiences for learning in the chemistry…

  4. A Multicenter Longitudinal Study of Hospital-Onset Bacteremia: Time for a New Quality Outcome Measure?

    PubMed

    Rock, Clare; Thom, Kerri A; Harris, Anthony D; Li, Shanahan; Morgan, Daniel; Milstone, Aaron M; Caffo, Brian; Joshi, Manjari; Leekha, Surbhi

    2016-02-01

    Central-line-associated bloodstream infection (CLABSI) rate is an important quality measure, but it suffers from subjectivity and interrater variability, and decreasing national CLABSI rates may compromise its power to discriminate between hospitals. This study evaluates hospital-onset bacteremia (HOB, ie, any positive blood culture obtained 48 hours post admission) as a healthcare-associated infection-related outcome measure by assessing the association between HOB and CLABSI rates and comparing the power of each to discriminate quality among intensive care units (ICUs). In this multicenter study, ICUs provided monthly CLABSI and HOB rates for 2012 and 2013. A Poisson regression model was used to assess the association between these 2 rates. We compared the power of each measure to discriminate between ICUs using standardized infection ratios (SIRs) with 95% confidence intervals (CIs). A measure was defined as having greater power to discriminate if more of the SIRs (with surrounding CIs) were different from 1. In 80 ICUs from 16 hospitals in the United States and Canada, a total of 663 CLABSIs, 475,420 central line days, 11,280 HOBs, and 966,757 patient days were reported. An absolute change in HOB of 1 per 1,000 patient days was associated with a 2.5% change in CLABSI rate (P<.001). Among the 80 ICUs, 20 (25%) had a CLABSI SIR and 60 (75%) had an HOB SIR that was different from 1 (P<.001). Change in HOB rate is strongly associated with change in CLABSI rate and has greater power to discriminate between ICU performances. Consideration should be given to using HOB to replace CLABSI as an outcome measure in infection prevention quality assessments.

  5. Collection of a Lifetime: A Practical Approach to Developing a Longitudinal Collection of Women’s Healthcare Biological Samples

    PubMed Central

    Santillan, Mark K.; Leslie, Kimberly K.; Hamilton, Wendy S.; Boese, Brenda J.; Ahuja, Monika; Hunter, Stephen K.; Santillan, Donna A.

    2014-01-01

    Objective The objective is to develop a biorepository of samples that represent all stages of a women’s life. Importantly, our goal is to collect longitudinal physical specimens as well as the associated short and long-term clinical information. Study Design The Women’s Health Tissue Repository was established to encompass four tissue banks: Well Women Tissue Bank, Reproductive Endocrinology & Infertility Tissue Bank, Maternal Fetal Tissue Bank, and the long-established Gynecologic Malignancies Tissue Bank. Based on their health status, women being seen in Women’s Health at the University of Iowa are recruited to contribute samples and grant access to their electronic medical record to the biorepository. Samples are coded, processed, and stored for use by investigators. Results The Maternal Fetal Tissue Bank was the first expansion of our department’s biobanking efforts. Approximately 75% of the women approached consent to participate in the Maternal Fetal Tissue Bank. Enrollment has steadily increased. Samples have been used for over 20 projects in the first 3 years and are critical to 7 funded grants and 3 patent applications. Conclusion Patient samples with corresponding clinical data are initially important to women’s health research. Our model demonstrates that many research projects by faculty, fellows, and residents have benefited from the existence of the Women’s Health Tissue Repository. While challenging to achieve, longitudinal sampling allows for the greatest opportunity to study normal and pathological changes throughout all phases of a women’s life, including pregnancy. This bank facilitates and accelerates the development of novel research, technologies, and possible therapeutic options in women’s health. The establishment of more longitudinal biorepositories based on our model would enhance women’s health research. PMID:24965987

  6. Accuracy and repeatability of Roentgen stereophotogrammetric analysis (RSA) for measuring knee laxity in longitudinal studies.

    PubMed

    Fleming, B C; Peura, G D; Abate, J A; Beynnon, B D

    2001-10-01

    Roentgen stereophotogrammetric analysis (RSA) can be used to assess temporal changes in anterior-posterior (A-P) knee laxity. However, the accuracy and precision of RSA is dependent on many factors and should be independently evaluated for a particular application. The objective of this study was to evaluate the use of RSA for measuring A-P knee laxity. The specific aims were to assess the variation or "noise" inherent to RSA, to determine the reproducibility of RSA for repeated A-P laxity testing, and to assess the accuracy of these measurements. Two experiments were performed. The first experiment utilized three rigid models of the tibiofemoral joint to assess the noise and to compare digitization errors of two independent examiners. No differences were found in the kinematic outputs of the RSA due to examiner, repeated trials, or the model used. In a second experiment, A-P laxity values between the A-P shear load limits of +/-60 N of five cadaver goat knees were measured to assess the error associated with repeated testing. The RSA laxity values were also compared to those obtained from a custom designed linkage system. The mean A-P laxity values with the knee 30 degrees, 60 degrees, and 90 degrees of flexion for the ACL-intact goat knee (+/-95% confidence interval) were 0.8 (+/-0.25), 0.9 (+/-0.29), and 0.4 (+/-0.22) mm, respectively. In the ACL-deficient knee, the A-P laxity values increased by an order of magnitude to 8.8 (+/-1.39), 7.6 (+/-1.32), and 3.1 (+/-1.20)mm, respectively. No significant differences were found between the A-P laxity values measured by RSA and the independent measurement technique. A highly significant linear relationship (r(2)=0.83) was also found between these techniques. This study suggests that the RSA method is an accurate and precise means to measure A-P knee laxity for repeated testing over time.

  7. Development and Validation of Army Selection and Classification Measures. Project A. Longitudinal Research Database Plan

    DTIC Science & Technology

    1983-12-01

    sound, and economical measures of these additional aspects of performance are not currently available. In addition to valid predictions of performance...Project A and the data to be acquired from existing Army files must be organized and stored in such a way that they are simple and economical to access...Census) data files containing information on local geographic or economic conditions. A1HOMADD STATE/COUNTY CODE OF HOME ADDRESS AIHOMZIP HOME ZIP

  8. The Impact of Social Media on Dissemination and Implementation of Clinical Practice Guidelines: A Longitudinal Observational Study.

    PubMed

    Narayanaswami, Pushpa; Gronseth, Gary; Dubinsky, Richard; Penfold-Murray, Rebecca; Cox, Julie; Bever, Christopher; Martins, Yolanda; Rheaume, Carol; Shouse, Denise; Getchius, Thomas S D

    2015-08-13

    Evidence-based clinical practice guidelines (CPGs) are statements that provide recommendations to optimize patient care for a specific clinical problem or question. Merely reading a guideline rarely leads to implementation of recommendations. The American Academy of Neurology (AAN) has a formal process of guideline development and dissemination. The last few years have seen a burgeoning of social media such as Facebook, Twitter, and LinkedIn, and newer methods of dissemination such as podcasts and webinars. The role of these media in guideline dissemination has not been studied. Systematic evaluation of dissemination methods and comparison of the effectiveness of newer methods with traditional methods is not available. It is also not known whether specific dissemination methods may be more effectively targeted to specific audiences. Our aim was to (1) develop an innovative dissemination strategy by adding social media-based dissemination methods to traditional methods for the AAN clinical practice guidelines "Complementary and alternative medicine in multiple sclerosis" ("CAM in MS") and (2) evaluate whether the addition of social media outreach improves awareness of the CPG and knowledge of CPG recommendations, and affects implementation of those recommendations. Outcomes were measured by four surveys in each of the two target populations: patients and physicians/clinicians ("physicians"). The primary outcome was the difference in participants' intent to discuss use of complementary and alternative medicine (CAM) with their physicians or patients, respectively, after novel dissemination, as compared with that after traditional dissemination. Secondary outcomes were changes in awareness of the CPG, knowledge of CPG content, and behavior regarding CAM use in multiple sclerosis (MS). Response rates were 25.08% (622/2480) for physicians and 43.5% (348/800) for patients. Awareness of the CPG increased after traditional dissemination (absolute difference, 95% confidence

  9. How Does Longitudinally Measured Maternal Expressed Emotion Affect Internalizing and Externalizing Symptoms of Adolescents from the General Community?

    ERIC Educational Resources Information Center

    Hale, William W., III; Keijsers, Loes; Klimstra, Theo A.; Raaijmakers, Quinten A. W.; Hawk, Skyler; Branje, Susan J. T.; Frijns, Tom; Wijsbroek, Saskia A. M.; van Lier, Pol; Meeus, Wim H. J.

    2011-01-01

    Background: In previous studies, maternal expressed emotion (EE) has been found to be a good predictor of the course of adolescent internalizing and externalizing symptoms. However, these studies have been cross-section as opposed to longitudinal. The goal of this study is to examine longitudinal data of perceived maternal EE and adolescent…

  10. Automated cross-sectional and longitudinal hippocampal volume measurement in mild cognitive impairment and Alzheimer's disease

    PubMed Central

    Leung, Kelvin K.; Barnes, Josephine; Ridgway, Gerard R.; Bartlett, Jonathan W.; Clarkson, Matthew J.; Macdonald, Kate; Schuff, Norbert; Fox, Nick C.; Ourselin, Sebastien

    2010-01-01

    Volume and change in volume of the hippocampus are both important markers of Alzheimer's disease (AD). Delineation of the structure on MRI is time-consuming and therefore reliable automated methods are required. We describe an improvement (multiple-atlas propagation and segmentation (MAPS)) to our template library-based segmentation technique. The improved technique uses non-linear registration of the best-matched templates from our manually-segmented library to generate multiple segmentations and combines them using the simultaneous truth and performance level estimation (STAPLE) algorithm. Change in volume over 12 months (MAPS-HBSI) was measured by applying the boundary shift integral using MAPS regions. Methods were developed and validated against manual measures using subsets from Alzheimer's Disease Neuroimaging Initiative (ADNI). The best method was applied to 682 ADNI subjects, at baseline and 12-month follow-up, enabling assessment of volumes and atrophy rates in control, mild cognitive impairment (MCI) and AD groups, and within MCI subgroups classified by subsequent clinical outcome. We compared our measures with those generated by SNT (Surgical Navigation Technologies) available from ADNI. The accuracy of our volumes was one of the highest reported (mean(SD) Jaccard Index 0.80(0.04) (N=30)). Both MAPS baseline volume and MAPS-HBSI atrophy rate distinguished between control, MCI and AD groups. Comparing MCI subgroups (reverters, stable and converters): volumes were lower and rates higher in converters compared with stable and reverter groups (p≤0.03). MAPS-HBSI required the lowest sample sizes (68 subjects) for a hypothetical trial. In conclusion, the MAPS and MAPS-HBSI methods give accurate and reliable volumes and atrophy rates across the clinical spectrum from healthy aging to AD. PMID:20230901

  11. Mediators of longitudinal changes in measures of adiposity in teenagers using parallel process latent growth modeling.

    PubMed

    Yιldιrιm, Mine; Singh, Amika S; te Velde, Saskia J; van Stralen, Maartje M; MacKinnon, David P; Brug, Johannes; van Mechelen, Willem; Chinapaw, Mai J M

    2013-11-01

    The aim of the study was to evaluate mediating effects of energy balance-related behaviors on measures of adiposity in the Dutch Obesity Intervention in Teenagers-study (DOiT). DOiT was an 8-month behavioral intervention program consisting of educational and environmental components and evaluated in 18 prevocational secondary schools in the Netherlands (n = 1,108, baseline age 12.7 years, 50% girls). Outcome measures were changes in body mass index (BMI), waist circumference, and sum of skinfold thickness. Self-reported consumption of sugar-containing beverages and high caloric snacks, active transport to/from school, and screen-viewing behaviors were the hypothesized mediators. Data were collected at 0, 8, 12, and 20 months. For the data analysis, parallel process latent growth modeling was used. Total sugar-containing beverages consumption mediated the intervention effects on BMI (ab = -0.01, 95%CI = -0.20, -0.001). The intervention group lowered their sugar-containing beverages consumption more than controls (B = -0.14, 95%CI = -0.22, -0.11) and this, in turn, led to smaller increases in BMI. No significant mediated effect by the targeted behaviors was found for waist circumference or sum of skinfolds. Future school-based overweight prevention interventions may target decreasing sugar-containing beverages consumption. Copyright © 2013 The Obesity Society.

  12. CROSS-SECTIONAL AND LONGITUDINAL MEASUREMENTS OF NEIGHBORHOOD EXPERIENCE AND THEIR EFFECTS ON CHILDREN*

    PubMed Central

    Jackson, Margot I.; Mare, Robert D.

    2014-01-01

    Despite the abundance of research on neighborhoods’ effects on children, most studies of neighborhood effects are cross-sectional, rendering them unable to depict the dynamic nature of social life, and obscuring important aspects of community processes and outcomes. This study uses residential histories from the Los Angeles Family and Neighborhood Survey and the Child Development Supplement of the Panel Study of Income Dynamics to explore two questions: 1) How much do residential mobility and neighborhood change contribute to the overall socioeconomic variation in children’s neighborhoods? 2) Does measuring community factors at more than one point in time matter for the conclusions that we draw from research on “neighborhood effects” on children’s behavioral, cognitive and health-related well-being? Residential mobility plays a non-trivial role over the period of childhood in determining children’s exposure to neighborhoods of different economic types. However, quantitative estimates of neighborhood effects that allow neighborhood characteristics to vary through residential mobility and neighborhood change do not depict a strikingly different picture from cross-sectional estimates. Children do not experience enough variation in their local surroundings to produce meaningful differences between static and dynamic measurements of neighborhoods. We also uncover interesting regional and race/ethnic differences in neighborhood dynamics and neighborhood effects. PMID:25197150

  13. A method for eliminating Faraday rotation in cryostat windows in longitudinal magneto-optical Kerr effect measurements

    SciTech Connect

    Polewko-Klim, A. Uba, S.; Uba, L.

    2014-07-15

    A solution to the problem of disturbing effect of the background Faraday rotation in the cryostat windows on longitudinal magneto-optical Kerr effect (LMOKE) measured under vacuum conditions and/or at low temperatures is proposed. The method for eliminating the influence of Faraday rotation in cryostat windows is based on special arrangement of additional mirrors placed on sample holder. In this arrangement, the orientation of the cryostat window is perpendicular to the light beam direction and parallel to an external magnetic field generated by the H-frame electromagnet. The operation of the LMOKE magnetometer with the special sample holder based on polarization modulation technique with a photo-elastic modulator is theoretically analyzed with the use of Jones matrices, and formulas for evaluating of the actual Kerr rotation and ellipticity of the sample are derived. The feasibility of the method and good performance of the magnetometer is experimentally demonstrated for the LMOKE effect measured in Fe/Au multilayer structures. The influence of imperfect alignment of the magnetometer setup on the Kerr angles, as derived theoretically through the analytic model and verified experimentally, is examined and discussed.

  14. A method for eliminating Faraday rotation in cryostat windows in longitudinal magneto-optical Kerr effect measurements.

    PubMed

    Polewko-Klim, A; Uba, S; Uba, L

    2014-07-01

    A solution to the problem of disturbing effect of the background Faraday rotation in the cryostat windows on longitudinal magneto-optical Kerr effect (LMOKE) measured under vacuum conditions and/or at low temperatures is proposed. The method for eliminating the influence of Faraday rotation in cryostat windows is based on special arrangement of additional mirrors placed on sample holder. In this arrangement, the orientation of the cryostat window is perpendicular to the light beam direction and parallel to an external magnetic field generated by the H-frame electromagnet. The operation of the LMOKE magnetometer with the special sample holder based on polarization modulation technique with a photo-elastic modulator is theoretically analyzed with the use of Jones matrices, and formulas for evaluating of the actual Kerr rotation and ellipticity of the sample are derived. The feasibility of the method and good performance of the magnetometer is experimentally demonstrated for the LMOKE effect measured in Fe/Au multilayer structures. The influence of imperfect alignment of the magnetometer setup on the Kerr angles, as derived theoretically through the analytic model and verified experimentally, is examined and discussed.

  15. Simultaneous measurement of longitudinal and lateral piezoelectric strain coefficients using digital image correlation

    NASA Astrophysics Data System (ADS)

    Malakooti, Mohammad H.; Sodano, Henry A.

    2013-04-01

    Here, Digital image correlation (DIC) is demonstrated to be an accurate tool for the noncontact, non-destructive and rapid characterization of the converse piezoelectric effect in bulk and thin films. The out-of-plane (d33) and in-plane (d31) piezoelectric strain coupling coefficients of PZT- 5H wafers are measured simultaneously by imaging the wafer's cross section under free mechanical boundary conditions. The large piezoresponse at switching domains and nonlinear behavior of PZT-5H are visualized in strain-electric field butterfly loops. The results show DIC as a simple advantageous technique to use for the characterization of piezoelectric materials under the influence of any field and physical constraints.

  16. Pre- and Postnatal Polychlorinated Biphenyl Concentrations and Longitudinal Measures of Thymus Volume in Infants

    PubMed Central

    Sonneborn, Dean; Palkovicova, Lubica; Kocan, Anton; Drobna, Beata; Trnovec, Tomas; Hertz-Picciotto, Irva

    2012-01-01

    Background: Previously, we reported an association between higher maternal polychlorinated biphenyl (PCB) concentrations and smaller thymus volume in newborns in a birth cohort residing in eastern Slovakia. Objective: In the present report we address whether thymus volume at later ages is influenced by prenatal and early postnatal PCB exposure. Methods: At the time of delivery, 1,134 mother–infant pairs were enrolled. Maternal and 6- and 16-month infant blood samples were collected and analyzed for 15 PCB congeners. Thymus volume was measured in infants shortly after birth and at ages 6 and 16 months using ultrasonography. Results: Higher maternal PCB concentration was associated with reduced thymus volume at birth [a 0.21 SD reduction in thymus volume for an increase in total maternal PCB concentration from the 10th to the 90th percentile; 95% confidence interval (CI): –0.37, –0.05], whereas maternal PCB concentration was not predictive of 6- and 16-month thymus volume. Six-month infant PCB concentration was associated with a 0.40 SD decrease in 6-month thymus volume (95% CI: –0.76, –0.04). There was also some suggestion that thymus volume at 16 months was positively associated with concurrent infant PCB concentration. Conclusions: The potential adverse effects of in utero PCB exposure on thymic development may extend beyond the neonatal period. Results from this highly exposed cohort provide suggestive evidence that postnatal PCB concentrations may be influential, but a smaller set of 6-month PCB measurements limited statistical power at that time point. Implications regarding impaired immunologic maturation or long-term clinical implications remain to be determined. PMID:22275729

  17. Timed Up & Go as a measure for longitudinal change in mobility after stroke - Postural Stroke Study in Gothenburg (POSTGOT).

    PubMed

    Persson, Carina U; Danielsson, Anna; Sunnerhagen, Katharina S; Grimby-Ekman, Anna; Hansson, Per-Olof

    2014-05-09

    A frequently used clinical test to assess mobility after stroke is the Timed Up & Go. Knowledge regarding whether or not the Timed Up & Go is able to detect change over time in patients with stroke, whether improvements in mobility exist after the first three months and whether or not longitudinal change in mobility after stroke depend on the patients' age, is limited or unclear. The objectives were to investigate the distribution-based responsiveness of the Timed Up & Go (TUG) during the first three months after a first event of stroke, to measure the longitudinal change in TUG time during the first year after stroke and to establish whether recovery in TUG time differs between different age groups. Ninety-one patients with first-ever stroke were assessed using the Timed Up & Go at the 1st week and at 3, 6 and 12 months after stroke. The non-parametric sign-test, the parametric t-test and a mixed model approach to linear regression for repeated measurements (Proc mixed) were used for the statistical analyses. The median TUG time was reduced from 17 to 12 seconds (p < 0.001) between the 1st week and 3 months. No further improvement was seen between 3 and 12 months after stroke. In a mixed model approach to linear regression, there was a significant age difference. Patients at age 80 and above tended to deteriorate in terms of TUG time between 3 and 12 months after stroke, while patients < 80 years did not (p = 0.011 for the interaction between age group and time). The Timed Up & Go demonstrates ability to detect change in mobility over time in patients with stroke. A significant improvement in TUG time from the 1st week to 3 months after stroke was found, as expected, but thereafter no statistically significant change was detected. After 3 months, patients ≥80 years tended to deteriorate in terms of TUG time, while the younger patients did not.

  18. Timed Up & Go as a measure for longitudinal change in mobility after stroke – Postural Stroke Study in Gothenburg (POSTGOT)

    PubMed Central

    2014-01-01

    Background A frequently used clinical test to assess mobility after stroke is the Timed Up & Go. Knowledge regarding whether or not the Timed Up & Go is able to detect change over time in patients with stroke, whether improvements in mobility exist after the first three months and whether or not longitudinal change in mobility after stroke depend on the patients’ age, is limited or unclear. The objectives were to investigate the distribution-based responsiveness of the Timed Up & Go (TUG) during the first three months after a first event of stroke, to measure the longitudinal change in TUG time during the first year after stroke and to establish whether recovery in TUG time differs between different age groups. Methods Ninety-one patients with first-ever stroke were assessed using the Timed Up & Go at the 1st week and at 3, 6 and 12 months after stroke. The non-parametric sign-test, the parametric t-test and a mixed model approach to linear regression for repeated measurements (Proc mixed) were used for the statistical analyses. Results The median TUG time was reduced from 17 to 12 seconds (p < 0.001) between the 1st week and 3 months. No further improvement was seen between 3 and 12 months after stroke. In a mixed model approach to linear regression, there was a significant age difference. Patients at age 80 and above tended to deteriorate in terms of TUG time between 3 and 12 months after stroke, while patients < 80 years did not (p = 0.011 for the interaction between age group and time). Conclusion The Timed Up & Go demonstrates ability to detect change in mobility over time in patients with stroke. A significant improvement in TUG time from the 1st week to 3 months after stroke was found, as expected, but thereafter no statistically significant change was detected. After 3 months, patients ≥80 years tended to deteriorate in terms of TUG time, while the younger patients did not. PMID:24885868

  19. Longitudinal measures of visual function, tumor volume, and prediction of visual outcomes after treatment of optic pathway gliomas.

    PubMed

    Kelly, John P; Leary, Sarah; Khanna, Paritosh; Weiss, Avery H

    2012-06-01

    To examine longitudinal changes in visual acuity, tumor volume, and visual evoked potentials (VEP) before and after treatment in children with optic pathway gliomas. Retrospective cohort study. Twenty-one patients (0.7-9 years of age). Patients initially were treated either by chemotherapy (n = 18) or radiotherapy (n = 3). Patients were followed up with serial magnetic resonance imaging, age-corrected visual acuity measurements in logarithm of the minimum angle of resolution (logMAR) units, and pattern VEP. Longitudinal visual outcome data were obtained on average for 9 years (range, 4-16 years). Tumor volumes before and after treatment were estimated in 15 patients. Multivariate regression was used to predict visual outcomes. Visual acuity, relative tumor volumes, and VEP. Before treatment, 81% of patients had reduced visual acuity and 81% had optic nerve pallor, whereas all had a reduced VEP in 1 or both eyes. After initial treatment, tumor volume decreased in 53%, stabilized in 27%, and progressively increased in 20%. Treatment arrested the rapid decline in visual acuity loss and stabilized visual acuity for 4 to 5 years. The rate of visual acuity decline was not correlated with tumor shrinkage. Sixty-two percent of patients required additional treatment with either chemotherapy or radiation because of tumor growth or progressive loss of visual function. Visual acuity at last examination was stable or improved in 33% of patients, but on average declined 0.4 logMAR units. Visual acuity was 20/200 or better in 1 eye of 62% of patients. The rate of visual acuity decline was predicted weakly by tumor volume at presentation (R(2) = 0.19; P<0.009). Visual acuity at last examination was predicted best by visual acuity and tumor volume at presentation (R(2) = 0.66; P<0.001). Systemic chemotherapy arrested the decline in visual acuity and stabilized vision on average for 5 years. At presentation, VEPs were a more sensitive indicator of optic pathway damage than visual

  20. Using the General Diagnostic Model to Measure Learning and Change in a Longitudinal Large-Scale Assessment. Research Report. ETS RR-09-28

    ERIC Educational Resources Information Center

    von Davier, Matthias; Xu, Xueli; Carstensen, Claus H.

    2009-01-01

    A general diagnostic model was used to specify and compare two multidimensional item-response-theory (MIRT) models for longitudinal data: (a) a model that handles repeated measurements as multiple, correlated variables over time (Andersen, 1985) and (b) a model that assumes one common variable over time and additional orthogonal variables that…

  1. The Effectiveness of Software Project Management Practices: A Quantitative Measurement

    DTIC Science & Technology

    2011-03-01

    management than most 6 professional managers expect ( Fairley , 2009). There are, in fact, very few Software Project Management Maturity Models (SPMMM) in...work activities and tasks that utilizes resources to achieve specified objectives within a prescribed time frame ( Fairley , 2009). Software Project...coordinating and leading, and managing risk factors for a software project ( Fairley , 2009). 11 Best Practices: Best practices are reusable

  2. Measurement of the longitudinal deuteron spin-structure function in deep-inelastic scattering

    SciTech Connect

    Bauer, J.M.

    1996-09-01

    Experiment E143 at SLAC performed deep-inelastic scattering measurements with polarized electrons incident on polarized protons and deuterons. The data for the beam energy of 29 GeV cover the kinematical range of x{sub Bj} > 0.03 and 1 < Q{sup 2} < 12 GeV{sup 2}. From these data, the spin-dependent structure functions g{sub 1} were determined. This dissertation describes the experiment and its analysis and discusses the results. The measured integral of g{sub 1}{sup d} over x from x = 0 to x = 1 is {Gamma}{sub 1}{sup d} = 0.046 {+-} 0.003 (stat){+-}0.004 (syst) at Q{sup 2} = 3 GeV{sup 2} and disagrees by more than three standard deviations with the prediction of the Ellis-Jaffe, sum rule. The data suggest that the quark contribution to the nucleon helicity is 0.35 {+-} 0.05. From the proton data of the same experiment, the integral over the proton spin-structure functional g{sub 1}{sup d} was determined to be {Gamma}{sub 1}{sup p} = 0.127 {+-} 0.003(stat){+-}0.008(syst). By Combining the deuteron data with the proton data, the integral {Gamma}{sub 1}{sup n} was extracted as {minus}0.027 {+-} 0.008 (stat){+-}0.010 (syst). The integral {Gamma}{sub 1}{sup p} {minus} {Gamma}{sub 1}{sup n} is 0.154{+-}0.010(stat) {+-}0.016 (syst) according to the E143 analysis. This result agrees with the important Bjorken sum rule of 0.171 {+-} 0.009 at Q{sup 2} = 3 GeV{sup 2} within less than one standard deviation. Furthermore, results of a separate analysis involving GLAP evolution equations are shown. Data were also collected for beam energies of 16.2 and 9.7 GeV, Results for g{sub 1} at these energies are presented.

  3. The World Health Organization Fetal Growth Charts: A Multinational Longitudinal Study of Ultrasound Biometric Measurements and Estimated Fetal Weight

    PubMed Central

    Carroli, Guillermo; Widmer, Mariana; Neerup Jensen, Lisa; Giordano, Daniel; Abdel Aleem, Hany; Talegawkar, Sameera A.; Benachi, Alexandra; Diemert, Anke; Tshefu Kitoto, Antoinette; Thinkhamrop, Jadsada; Lumbiganon, Pisake; Tabor, Ann; Kriplani, Alka; Gonzalez Perez, Rogelio; Hecher, Kurt; Hanson, Mark A.; Gülmezoglu, A. Metin; Platt, Lawrence D.

    2017-01-01

    Background Perinatal mortality and morbidity continue to be major global health challenges strongly associated with prematurity and reduced fetal growth, an issue of further interest given the mounting evidence that fetal growth in general is linked to degrees of risk of common noncommunicable diseases in adulthood. Against this background, WHO made it a high priority to provide the present fetal growth charts for estimated fetal weight (EFW) and common ultrasound biometric measurements intended for worldwide use. Methods and Findings We conducted a multinational prospective observational longitudinal study of fetal growth in low-risk singleton pregnancies of women of high or middle socioeconomic status and without known environmental constraints on fetal growth. Centers in ten countries (Argentina, Brazil, Democratic Republic of the Congo, Denmark, Egypt, France, Germany, India, Norway, and Thailand) recruited participants who had reliable information on last menstrual period and gestational age confirmed by crown–rump length measured at 8–13 wk of gestation. Participants had anthropometric and nutritional assessments and seven scheduled ultrasound examinations during pregnancy. Fifty-two participants withdrew consent, and 1,387 participated in the study. At study entry, median maternal age was 28 y (interquartile range [IQR] 25–31), median height was 162 cm (IQR 157–168), median weight was 61 kg (IQR 55–68), 58% of the women were nulliparous, and median daily caloric intake was 1,840 cal (IQR 1,487–2,222). The median pregnancy duration was 39 wk (IQR 38–40) although there were significant differences between countries, the largest difference being 12 d (95% CI 8–16). The median birthweight was 3,300 g (IQR 2,980–3,615). There were differences in birthweight between countries, e.g., India had significantly smaller neonates than the other countries, even after adjusting for gestational age. Thirty-one women had a miscarriage, and three fetuses had

  4. The World Health Organization Fetal Growth Charts: A Multinational Longitudinal Study of Ultrasound Biometric Measurements and Estimated Fetal Weight.

    PubMed

    Kiserud, Torvid; Piaggio, Gilda; Carroli, Guillermo; Widmer, Mariana; Carvalho, José; Neerup Jensen, Lisa; Giordano, Daniel; Cecatti, José Guilherme; Abdel Aleem, Hany; Talegawkar, Sameera A; Benachi, Alexandra; Diemert, Anke; Tshefu Kitoto, Antoinette; Thinkhamrop, Jadsada; Lumbiganon, Pisake; Tabor, Ann; Kriplani, Alka; Gonzalez Perez, Rogelio; Hecher, Kurt; Hanson, Mark A; Gülmezoglu, A Metin; Platt, Lawrence D

    2017-01-01

    Perinatal mortality and morbidity continue to be major global health challenges strongly associated with prematurity and reduced fetal growth, an issue of further interest given the mounting evidence that fetal growth in general is linked to degrees of risk of common noncommunicable diseases in adulthood. Against this background, WHO made it a high priority to provide the present fetal growth charts for estimated fetal weight (EFW) and common ultrasound biometric measurements intended for worldwide use. We conducted a multinational prospective observational longitudinal study of fetal growth in low-risk singleton pregnancies of women of high or middle socioeconomic status and without known environmental constraints on fetal growth. Centers in ten countries (Argentina, Brazil, Democratic Republic of the Congo, Denmark, Egypt, France, Germany, India, Norway, and Thailand) recruited participants who had reliable information on last menstrual period and gestational age confirmed by crown-rump length measured at 8-13 wk of gestation. Participants had anthropometric and nutritional assessments and seven scheduled ultrasound examinations during pregnancy. Fifty-two participants withdrew consent, and 1,387 participated in the study. At study entry, median maternal age was 28 y (interquartile range [IQR] 25-31), median height was 162 cm (IQR 157-168), median weight was 61 kg (IQR 55-68), 58% of the women were nulliparous, and median daily caloric intake was 1,840 cal (IQR 1,487-2,222). The median pregnancy duration was 39 wk (IQR 38-40) although there were significant differences between countries, the largest difference being 12 d (95% CI 8-16). The median birthweight was 3,300 g (IQR 2,980-3,615). There were differences in birthweight between countries, e.g., India had significantly smaller neonates than the other countries, even after adjusting for gestational age. Thirty-one women had a miscarriage, and three fetuses had intrauterine death. The 8,203 sets of ultrasound

  5. Graphic methods for interpreting longitudinal dyadic patterns from repeated-measures actor-partner interdependence models.

    PubMed

    Perry, Nicholas S; Baucom, Katherine J W; Bourne, Stacia; Butner, Jonathan; Crenshaw, Alexander O; Hogan, Jasara N; Imel, Zac E; Wiltshire, Travis J; Baucom, Brian R W

    2017-08-01

    Researchers commonly use repeated-measures actor-partner interdependence models (RM-APIM) to understand how romantic partners change in relation to one another over time. However, traditional interpretations of the results of these models do not fully or correctly capture the dyadic temporal patterns estimated in RM-APIM. Interpretation of results from these models largely focuses on the meaning of single-parameter estimates in isolation from all the others. However, considering individual coefficients separately impedes the understanding of how these associations combine to produce an interdependent pattern that emerges over time. Additionally, positive within-person, or actor, effects are commonly misinterpreted as indicating growth from one time point to the next when they actually represent decline. We suggest that change-as-outcome RM-APIMs and vector field diagrams (VFDs) can be used to improve the understanding and presentation of dyadic patterns of association described by standard RM-APIMs. The current article briefly reviews the conceptual foundations of RM-APIMs, demonstrates how change-as-outcome RM-APIMs and VFDs can aid interpretation of standard RM-APIMs, and provides a tutorial in making VFDs using multilevel modeling. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  6. Adaptive Quantification and Longitudinal Analysis of Pulmonary Emphysema with a Hidden Markov Measure Field Model

    PubMed Central

    Häme, Yrjö; Angelini, Elsa D.; Hoffman, Eric A.; Barr, R. Graham; Laine, Andrew F.

    2014-01-01

    The extent of pulmonary emphysema is commonly estimated from CT images by computing the proportional area of voxels below a predefined attenuation threshold. However, the reliability of this approach is limited by several factors that affect the CT intensity distributions in the lung. This work presents a novel method for emphysema quantification, based on parametric modeling of intensity distributions in the lung and a hidden Markov measure field model to segment emphysematous regions. The framework adapts to the characteristics of an image to ensure a robust quantification of emphysema under varying CT imaging protocols and differences in parenchymal intensity distributions due to factors such as inspiration level. Compared to standard approaches, the present model involves a larger number of parameters, most of which can be estimated from data, to handle the variability encountered in lung CT scans. The method was used to quantify emphysema on a cohort of 87 subjects, with repeated CT scans acquired over a time period of 8 years using different imaging protocols. The scans were acquired approximately annually, and the data set included a total of 365 scans. The results show that the emphysema estimates produced by the proposed method have very high intra-subject correlation values. By reducing sensitivity to changes in imaging protocol, the method provides a more robust estimate than standard approaches. In addition, the generated emphysema delineations promise great advantages for regional analysis of emphysema extent and progression, possibly advancing disease subtyping. PMID:24759984

  7. Longitudinal changes in heart rate-corrected measures of exercise performance in children.

    PubMed

    Chintala, Kavitha; Epstein, Michael L; Singh, Tajinder P

    2008-01-01

    Interpretation of change in exercise performance over time in children with repaired congenital heart disease is often hampered by poor effort that limits the maximum heart rate; this is often difficult to distinguish from chronotropic impairment, a common finding in these children. In an attempt to address this limitation, we sought to examine measures of exercise performance that are corrected for heart rate in healthy children and to determine if these change with somatic growth. We studied two serial graded exercise tests in 24 healthy children at an interval of >3 years. Paired comparisons revealed that maximum oxygen pulse (O(2) pulse), O(2) pulse at ventilatory anaerobic threshold, O(2) pulse at a heart rate of 140 beats per minute, and slope of the VO(2)-heart rate relationship all increased with age. However, when indexed to somatic growth, there was no change in the mean values of these parameters over time. We conclude that O(2 )pulse and slope of the VO(2)-heart rate relationship during exercise increase in proportion to somatic growth in children so that optimal oxygen delivery to the exercising muscles is ensured. This study provides the "normative" response of exercise parameters to growth, against which responses of children with repaired congenital heart disease may be compared.

  8. Construction and updating of a public events questionnaire for repeated measures longitudinal studies

    PubMed Central

    Noone, Martha; Semkovska, Maria; Carton, Mary; Dunne, Ross; Horgan, John-Paul; O'Kane, Breige; McLoughlin, Declan M.

    2014-01-01

    Impairments of retrospective memory and cases of retrograde amnesia are often seen in clinical settings. A measure of the proportion of memories retained over a specified time can be useful in clinical situations and public events questionnaires may be valuable in this respect. However, consistency of retention of public events memory has rarely been studied in the same participants. In addition, when used in a research context, public events questionnaires require updating to ensure questions are of equivalent age with respect to when the test is taken. This paper describes an approach to constructing and updating a Public Events Questionnaire (PEQ) for use with a sample that is recruited and followed-up over a long time-period. Internal consistency, parallel-form reliability, test-retest reliability, and secondary validity analyses were examined for three versions of the PEQ that were updated every 6 months. Versions 2 and 3 of the questionnaire were reliable across and within versions and for recall and recognition. Change over time was comparable across each version of the PEQ. These results show that PEQs can be regularly updated in a standardized fashion to allow use throughout studies with long recruitment periods. PMID:24678306

  9. The evolution and development of an instrument to measure essential professional nursing practices.

    PubMed

    Kramer, Marlene; Brewer, Barbara B; Halfer, Diana; Hnatiuk, Cynthia Nowicki; MacPhee, Maura; Schmalenberg, Claudia

    2014-11-01

    Nursing continues to evolve from a task-oriented occupation to a holistic professional practice. Increased professionalism requires accurate measurement of care processes and practice. Nursing studies often omit measurement of the relationship between structures in the work environment and processes of care or between processes of care and patient outcomes. Process measurement is integral to understanding and improving nursing practice. This article describes the development of an updated Essentials of Magnetism process measurement instrument for clinical nurses (CNs) practicing on inpatient units in hospitals. It has been renamed Essential Professional Nursing Practices: CN.

  10. Within-patient longitudinal speech reception measures with continuous interleaved sampling processors for ineraid implanted subjects.

    PubMed

    Pelizzone, M; Cosendai, G; Tinembart, J

    1999-06-01

    To assess within-subject changes in speech reception over time in a group of Ineraid subjects fitted with continuous interleaved sampling (CIS) wearable processors fabricated in Geneva. To compare asymptotic performance between CIS and Ineraid processors for the same subjects. Twelve patients, all users of the 4-channel Ineraid cochlear implant system for several years and with no previous experience of CIS processors in daily life, were equipped with Geneva Wearable Processors programmed to implement a high-rate CIS sound processing strategy using four to six channels. Their speech reception performance with CIS processors was monitored over a period of 1 yr with consonant and vowel identification tests. For comparison, speech reception performance also was measured with Ineraid processors before switching to CIS and after 6 mo of non-use of Ineraid processors. At fitting, CIS processors produced significantly better consonant identification but no better vowel identification. Subsequently, consonant and vowel scores with CIS processors improved progressively to asymptote after 6 mo of daily use. At 6 mo and beyond, performance with CIS processors was significantly superior to that obtained with Ineraid processors on both consonant and vowel identification tests. Control tests made with Ineraid processors after 6 mo of non-use of the device yielded results that were indistinguishable from those obtained before the study. The full potential of the CIS strategy is not revealed at fitting. Accumulation of daily experience provides significant improvements, asymptotic performance being reached after about 4 to 6 mo of use. All Ineraid users might greatly benefit from CIS processors.

  11. Acoustic Radiation Force Impulse Measurement in Renal Transplantation: A Prospective, Longitudinal Study With Protocol Biopsies.

    PubMed

    Lee, Juhan; Oh, Young Taik; Joo, Dong Jin; Ma, Bo Gyoung; Lee, A-lan; Lee, Jae Geun; Song, Seung Hwan; Kim, Seung Up; Jung, Dae Chul; Chung, Yong Eun; Kim, Yu Seun

    2015-09-01

    Interstitial fibrosis and tubular atrophy (IF/TA) is a common cause of kidney allograft loss. Several noninvasive techniques developed to assess tissue fibrosis are widely used to examine the liver. However, relatively few studies have investigated the use of elastographic methods to assess transplanted kidneys. The aim of this study was to explore the clinical implications of the acoustic radiation force impulse (ARFI) technique in renal transplant patients. A total of 91 patients who underwent living donor renal transplantation between September 2010 and January 2013 were included in this prospective study. Shear wave velocity (SWV) was measured by ARFI at baseline and predetermined time points (1 week and 6 and 12 months after transplantation). Protocol biopsies were performed at 12 months. Instead of reflecting IF/TA, SWVs were found to be related to time elapsed after transplantation. Mean SWV increased continuously during the first postoperative year (P < 0.001). In addition, mixed model analysis showed no correlation existed between SWV and serum creatinine (r = -0.2426, P = 0.0771). There was also no evidence of a relationship between IF/TA and serum creatinine (odds ratio [OR] = 1.220, P = 0.7648). Furthermore, SWV temporal patterns were dependent on the kidney weight to body weight ratio (KW/BW). In patients with a KW/BW < 3.5 g/kg, mean SWV continuously increased for 12 months, whereas it decreased after 6 months in those with a KW/BW ≥ 3.5 g/kg.No significant correlation was observed between SWV and IF/TA or renal dysfunction. However, SWV was found to be related to the time after transplantation. Renal hemodynamics influenced by KW/BW might impact SWV values.

  12. Quantitative Measurement of Longitudinal and Transverse Cross-Relaxation Rates: An Application to the Analysis of the Internal Dynamics of Ranalexin in Water and Trifluoroethanol

    NASA Astrophysics Data System (ADS)

    Malliavin, T. E.; Desvaux, H.; Aumelas, A.; Chavanieu, A.; Delsuc, M. A.

    1999-09-01

    We describe a quantitative processing method which gives access to the longitudinal and transverse cross-relaxation rates from off-resonance ROESY intensities. This method takes advantage of the dependence of the off-resonance ROESY experiments at any mixing time and any spin-lock angle θ on two relaxation matrices, the longitudinal and the transverse ones. This allows one to take into account multistep magnetization transfers even if the measurements are performed only at one or two mixing times. The ratio of the longitudinal to transverse cross-relaxation rates can then be used as a local indicator of the internal dynamics, without assuming a structure or a model of motion. After validation of this processing method by numerical simulations, it is applied to the analysis of the dynamics of the peptide ranalexin dissolved in pure water and in water/TFE.

  13. Quantitative measurement of longitudinal and transverse cross-relaxation rates: an application to the analysis of the internal dynamics of ranalexin in water and trifluoroethanol.

    PubMed

    Malliavin, T E; Desvaux, H; Aumelas, A; Chavanieu, A; Delsuc, M A

    1999-09-01

    We describe a quantitative processing method which gives access to the longitudinal and transverse cross-relaxation rates from off-resonance ROESY intensities. This method takes advantage of the dependence of the off-resonance ROESY experiments at any mixing time and any spin-lock angle θ on two relaxation matrices, the longitudinal and the transverse ones. This allows one to take into account multistep magnetization transfers even if the measurements are performed only at one or two mixing times. The ratio of the longitudinal to transverse cross-relaxation rates can then be used as a local indicator of the internal dynamics, without assuming a structure or a model of motion. After validation of this processing method by numerical simulations, it is applied to the analysis of the dynamics of the peptide ranalexin dissolved in pure water and in water/TFE. Copyright 1999 Academic Press.

  14. Measurement of R = {sigma}{sub L}/{sigma}{sub T} and the Separated Longitudinal and Transverse Structure Functions in the Nucleon Resonance Region

    SciTech Connect

    Yongguang Liang; Michael Christy; Abdellah Ahmidouch; Christopher Armstrong; John Arrington; Arshak Asaturyan; Steven Avery; O. Baker; Douglas Beck; Henk Blok; C.W. Bochna; Werner Boeglin; Peter Bosted; Maurice Bouwhuis; Herbert Breuer; Daniel Brown; Antje Bruell; Roger Carlini; Jinseok Cha; Nicholas Chant; Anthony Cochran; Leon Cole; Samuel Danagoulian; Donal Day; James Dunne; Dipangkar Dutta; Rolf Ent; Howard Fenker; B. Fox; Liping Gan; Haiyan Gao; Kenneth Garrow; David Gaskell; Ashot Gasparian; Don Geesaman; Ronald Gilman; Paul Gueye; Mark Harvey; Roy Holt; Xiaodong Jiang; Mark Jones; Cynthia Keppel; Edward Kinney; Wolfgang Lorenzon; Allison Lung; David Mack; Pete Markowitz; J.W. Martin; Kevin McIlhany; Daniella Mckee; David Meekins; M.A. Miller; Richard Milner; Joseph Mitchell; Hamlet Mkrtchyan; Robert Mueller; Alan Nathan; Gabriel Niculescu; Maria-Ioana Niculescu; Thomas O'neill; Vassilios Papavassiliou; Stephen Pate; Rodney Piercey; David Potterveld; Ronald Ransome; Joerg Reinhold; E. Rollinde; Oscar Rondon-Aramayo; Philip Roos; Adam Sarty; Reyad Sawafta; Elaine Schulte; Edwin Segbefia; C. Smith; Samuel Stepanyan; Steffen Strauch; Vardan Tadevosyan; Liguang Tang; Raphael Tieulent; Vladas Tvaskis; Alicia Uzzle; William Vulcan; Stephen Wood; Feng Xiong; Lulin Yuan; Markus Zeier; Benedikt Zihlmann; Vitaliy Ziskin

    2004-10-01

    We report on a detailed study of longitudinal strength in the nucleon resonance region, presenting new results from inclusive electron-proton cross sections measured at Jefferson Lab Hall C in the four-momentum transfer range 0.2 < Q{sup 2} < 5.5 GeV{sup 2}. The data have been used to accurately perform over 170 Rosenbluth-type longitudinal/transverse separations. The precision R = {sigma}{sub L}/{sigma}{sub T} data are presented here, along with the first separate values of the inelastic structure functions F{sub 1} and F{sub L} in this regime. The resonance longitudinal component is found to be significant. With the new data, quark-hadron duality is observed above Q{sup 2} = 1 GeV{sup 2} in the separated structure functions independently.

  15. The Impact of Social Media on Dissemination and Implementation of Clinical Practice Guidelines: A Longitudinal Observational Study

    PubMed Central

    Gronseth, Gary; Dubinsky, Richard; Penfold-Murray, Rebecca; Cox, Julie; Bever Jr, Christopher; Martins, Yolanda; Rheaume, Carol; Shouse, Denise; Getchius, Thomas SD

    2015-01-01

    Background Evidence-based clinical practice guidelines (CPGs) are statements that provide recommendations to optimize patient care for a specific clinical problem or question. Merely reading a guideline rarely leads to implementation of recommendations. The American Academy of Neurology (AAN) has a formal process of guideline development and dissemination. The last few years have seen a burgeoning of social media such as Facebook, Twitter, and LinkedIn, and newer methods of dissemination such as podcasts and webinars. The role of these media in guideline dissemination has not been studied. Systematic evaluation of dissemination methods and comparison of the effectiveness of newer methods with traditional methods is not available. It is also not known whether specific dissemination methods may be more effectively targeted to specific audiences. Objective Our aim was to (1) develop an innovative dissemination strategy by adding social media-based dissemination methods to traditional methods for the AAN clinical practice guidelines “Complementary and alternative medicine in multiple sclerosis” (“CAM in MS”) and (2) evaluate whether the addition of social media outreach improves awareness of the CPG and knowledge of CPG recommendations, and affects implementation of those recommendations. Methods Outcomes were measured by four surveys in each of the two target populations: patients and physicians/clinicians (“physicians”). The primary outcome was the difference in participants’ intent to discuss use of complementary and alternative medicine (CAM) with their physicians or patients, respectively, after novel dissemination, as compared with that after traditional dissemination. Secondary outcomes were changes in awareness of the CPG, knowledge of CPG content, and behavior regarding CAM use in multiple sclerosis (MS). Results Response rates were 25.08% (622/2480) for physicians and 43.5% (348/800) for patients. Awareness of the CPG increased after traditional

  16. Reliability of longitudinal brain volume loss measurements between 2 sites in patients with multiple sclerosis: comparison of 7 quantification techniques.

    PubMed

    Durand-Dubief, F; Belaroussi, B; Armspach, J P; Dufour, M; Roggerone, S; Vukusic, S; Hannoun, S; Sappey-Marinier, D; Confavreux, C; Cotton, F

    2012-11-01

    Brain volume loss is currently a MR imaging marker of neurodegeneration in MS. Available quantification algorithms perform either direct (segmentation-based techniques) or indirect (registration-based techniques) measurements. Because there is no reference standard technique, the assessment of their accuracy and reliability remains a difficult goal. Therefore, the purpose of this work was to assess the robustness of 7 different postprocessing algorithms applied to images acquired from different MR imaging systems. Nine patients with MS were followed longitudinally over 1 year (3 time points) on two 1.5T MR imaging systems. Brain volume change measures were assessed using 7 segmentation algorithms: a segmentation-classification algorithm, FreeSurfer, BBSI, KN-BSI, SIENA, SIENAX, and JI algorithm. Intersite variability showed that segmentation-based techniques and SIENAX provided large and heterogeneous values of brain volume changes. A Bland-Altman analysis showed a mean difference of 1.8%, 0.07%, and 0.79% between the 2 sites, and a wide length agreement interval of 11.66%, 7.92%, and 11.94% for the segmentation-classification algorithm, FreeSurfer, and SIENAX, respectively. In contrast, registration-based algorithms showed better reproducibility, with a low mean difference of 0.45% for BBSI, KN-BSI and JI, and a mean length agreement interval of 1.55%. If SIENA obtained a lower mean difference of 0.12%, its agreement interval of 3.29% was wider. If brain atrophy estimation remains an open issue, future investigations of the accuracy and reliability of the brain volume quantification algorithms are needed to measure the slow and small brain volume changes occurring in MS.

  17. Longitudinal assessment of hydropeaking impacts on various scales for an improved process understanding and the design of mitigation measures.

    PubMed

    Hauer, C; Holzapfel, P; Leitner, P; Graf, W

    2017-01-01

    Hydropeaking is one of the main pressures on the aquatic ecology in alpine rivers. Beside studies on abiotic process and biotic response on the local scale there is a lack in process understanding on the reach scale. Especially longitudinal changes of hydropeaking impacts based on retention processes have not been studied yet. Thus, based on unsteady one-dimensional and two-dimensional depth averaged modelling it was targeted to investigate possible changes in vertical ramping velocity for the discussion of possible mitigation measures at the local scale. Here, we compared artificial and natural sheltering habitats in terms of peak flow. Additionally, the hydropeaking assessment on various river scales was supported by an evaluation of tributaries in an alpine river system. Based on the modelling results and the discussion of the impact assessment of hydropeaking in different case studies we state, that on the first 5km downstream of the turbine outlet a significant decrease in vertical ramping velocity occurs. In this reach, habitat improvements should focus on increasing retention processes considering the higher risk of stranding for juvenile fish and macroinvertebrates. For morphological mitigation measures at the local scale, it turned out that self-formed, near-natural morphology should be targeted in terms of mitigation measure design compared to artificial sheltering habitats. Abundance and biomass of macroinvertebrates are directly linked to substrate variability in self-formed sheltering habitats downstream of gravel bars. Moreover, we ascertained that tributaries are able to contribute to the 'ecological potential' in multi-stressed hydropeaking rivers by providing spawning and rearing habitats for fish. However, for a sustainable improvement of the aquatic environment on all relevant scales, both sediment and flood dynamics have to be considered as important drivers to establish self-formed sheltering habitats in terms of hydropeaking. Copyright © 2016

  18. An embedded longitudinal multi-faceted qualitative evaluation of a complex cluster randomized controlled trial aiming to reduce clinically important errors in medicines management in general practice.

    PubMed

    Cresswell, Kathrin M; Sadler, Stacey; Rodgers, Sarah; Avery, Anthony; Cantrill, Judith; Murray, Scott A; Sheikh, Aziz

    2012-06-08

    There is a need to shed light on the pathways through which complex interventions mediate their effects in order to enable critical reflection on their transferability. We sought to explore and understand key stakeholder accounts of the acceptability, likely impact and strategies for optimizing and rolling-out a successful pharmacist-led information technology-enabled (PINCER) intervention, which substantially reduced the risk of clinically important errors in medicines management in primary care. Data were collected at two geographical locations in central England through a combination of one-to-one longitudinal semi-structured telephone interviews (one at the beginning of the trial and another when the trial was well underway), relevant documents, and focus group discussions following delivery of the PINCER intervention. Participants included PINCER pharmacists, general practice staff, researchers involved in the running of the trial, and primary care trust staff. PINCER pharmacists were interviewed at three different time-points during the delivery of the PINCER intervention. Analysis was thematic with diffusion of innovation theory providing a theoretical framework. We conducted 52 semi-structured telephone interviews and six focus group discussions with 30 additional participants. In addition, documentary data were collected from six pharmacist diaries, along with notes from four meetings of the PINCER pharmacists and feedback meetings from 34 practices. Key findings that helped to explain the success of the PINCER intervention included the perceived importance of focusing on prescribing errors to all stakeholders, and the credibility and appropriateness of a pharmacist-led intervention to address these shortcomings. Central to this was the face-to-face contact and relationship building between pharmacists and a range of practice staff, and pharmacists' explicitly designated role as a change agent. However, important concerns were identified about the likely

  19. An embedded longitudinal multi-faceted qualitative evaluation of a complex cluster randomized controlled trial aiming to reduce clinically important errors in medicines management in general practice

    PubMed Central

    2012-01-01

    Background There is a need to shed light on the pathways through which complex interventions mediate their effects in order to enable critical reflection on their transferability. We sought to explore and understand key stakeholder accounts of the acceptability, likely impact and strategies for optimizing and rolling-out a successful pharmacist-led information technology-enabled (PINCER) intervention, which substantially reduced the risk of clinically important errors in medicines management in primary care. Methods Data were collected at two geographical locations in central England through a combination of one-to-one longitudinal semi-structured telephone interviews (one at the beginning of the trial and another when the trial was well underway), relevant documents, and focus group discussions following delivery of the PINCER intervention. Participants included PINCER pharmacists, general practice staff, researchers involved in the running of the trial, and primary care trust staff. PINCER pharmacists were interviewed at three different time-points during the delivery of the PINCER intervention. Analysis was thematic with diffusion of innovation theory providing a theoretical framework. Results We conducted 52 semi-structured telephone interviews and six focus group discussions with 30 additional participants. In addition, documentary data were collected from six pharmacist diaries, along with notes from four meetings of the PINCER pharmacists and feedback meetings from 34 practices. Key findings that helped to explain the success of the PINCER intervention included the perceived importance of focusing on prescribing errors to all stakeholders, and the credibility and appropriateness of a pharmacist-led intervention to address these shortcomings. Central to this was the face-to-face contact and relationship building between pharmacists and a range of practice staff, and pharmacists’ explicitly designated role as a change agent. However, important concerns were

  20. A Preference Based Measure of Complementary Feeding Quality: Application to the Avon Longitudinal Study of Parents and Children

    PubMed Central

    Mittinty, Murthy N.; Golley, Rebecca K.; Smithers, Lisa G.; Brazionis, Laima; Lynch, John W.

    2013-01-01

    This paper presents the development of the Complementary Feeding Utility Index (CFUI), a composite index aimed to measure adherence to infant feeding guidelines. Through an axiomatic characterization this paper shows the advantages in using the CFUI are the following: it avoids the use of arbitrary cut-offs, and by converting observed diet preferences into utilities, summing the score is meaningful. In addition, as the CFUI is designed to be scored continuously, it allows the transition from intake of beneficial foods (in low quantities) and intake of detrimental foods (in high quantities) to be more subtle. The paper first describes the rationale being the development of the CFUI and then elaborates on the methodology used to develop the CFUI, including the process of selecting the components. The methodology is applied to data collected from the Avon Longitudinal Study of Parents and Children to show the advantages of the CFUI over traditional diet index approaches. Unlike traditional approaches, the distribution of the CFUI does not peak towards mean value but distributes evenly towards the tails of the distribution. PMID:24155886

  1. Measurement of parity-violating spin asymmetries in W± production at midrapidity in longitudinally polarized p+p collisions

    DOE PAGES

    Adare, A.

    2016-03-23

    In this article, we present midrapidity measurements from the PHENIX experiment of large parity-violating single-spin asymmetries of high transverse momentum electrons and positrons from W±/Z decays, produced in longitudinally polarized p+p collisions at center of mass energies of √s=500 and 510 GeV. These asymmetries allow direct access to the antiquark polarized parton distribution functions due to the parity-violating nature of the W-boson coupling to quarks and antiquarks. The results presented are based on data collected in 2011, 2012, and 2013 with an integrated luminosity of 240 pb-1, which exceeds previous PHENIX published results by a factor of more than 27.more » In addition, these high Q2 data probe the parton structure of the proton at W mass scale and provide an important addition to our understanding of the antiquark parton helicity distribution functions at an intermediate Bjorken x value of roughly MW/√s=0.16.« less

  2. Longitudinal Inter-Comparison of Modeled and Measured West Greenland Ice Sheet Meltwater Runoff Losses (2004-2014)

    NASA Astrophysics Data System (ADS)

    Moustafa, S.; Rennermalm, A. K.; Tedesco, M.; Mote, T. L.; Koenig, L.; Smith, L. C.; Hagedorn, B.; Overeem, I.; Sletten, R. S.; Mikkelsen, A. B.; Hasholt, B.; Hall, D. K.

    2015-12-01

    Increased surface meltwater runoff, that exits the Greenland ice sheet (GrIS) margin via supra-, en-, and sub-glacial drainage networks into fjords, pro-glacial lakes and rivers, accounts for half or more of total mass loss. Despite its importance, modeled meltwater runoff fluxes are poorly constrained, primarily due to a lack of direct in situ observations. Here, we present the first ever longitudinal (north-south) inter-comparison of a multi-year dataset (2004-2014) of discharge for four drainage basins - Watson, Akuliarusiarsuup Kuua, Naujat Kuat, and North Rivers - along West Greenland. These in situ hydrologic measurements are compared with modeled runoff output from Modèle Atmosphérique Régional (MAR) regional climate model, and the performance of the model is examined. An analysis of the relationship between modeled and actual ice sheet runoff patterns is assessed, and provides insight into the model's ability to capture inter-annual and intra-annual variability, spatiotemporal patterns, and extreme melt events. This study's findings will inform future development and parameterization of ice sheet surface mass balance models.

  3. Measurement of Longitudinal β-Amyloid Change with 18F-Florbetapir PET and Standardized Uptake Value Ratios

    PubMed Central

    Landau, Susan M.; Fero, Allison; Baker, Suzanne L.; Koeppe, Robert; Mintun, Mark; Chen, Kewei; Reiman, Eric M.; Jagust, William J.

    2017-01-01

    The accurate measurement of β-amyloid (Aβ) change using amyloid PET imaging is important for Alzheimer disease research and clinical trials but poses several unique challenges. In particular, reference region measurement instability may lead to spurious changes in cortical regions of interest. To optimize our ability to measure 18F-florbetapir longitudinal change, we evaluated several candidate regions of interest and their influence on cortical florbetapir change over a 2-y period in participants from the Alzheimer Disease Neuroimaging Initiative (ADNI). Methods We examined the agreement in cortical florbetapir change detected using 6 candidate reference regions (cerebellar gray matter, whole cerebellum, brain stem/pons, eroded subcortical white matter [WM], and 2 additional combinations of these regions) in 520 ADNI subjects. We used concurrent cerebrospinal fluid Aβ1–42 measurements to identify subgroups of ADNI subjects expected to remain stable over follow-up (stable Aβ group; n = 14) and subjects expected to increase (increasing Aβ group; n = 91). We then evaluated reference regions according to whether cortical change was minimal in the stable Aβ group and cortical retention increased in the increasing Aβ group. Results There was poor agreement across reference regions in the amount of cortical change observed across all 520 ADNI subjects. Within the stable Aβ group, however, cortical florbetapir change was 1%–2% across all reference regions, indicating high consistency. In the increasing Aβ group, cortical increases were significant with all reference regions. Reference regions containing WM (as opposed to cerebellum or pons) enabled detection of cortical change that was more physiologically plausible and more likely to increase over time. Conclusion Reference region selection has an important influence on the detection of florbetapir change. Compared with cerebellum or pons alone, reference regions that included subcortical WM resulted in

  4. Changes in Veterinary Students' Attitudes Toward the Rural Environment and Rural Veterinary Practice: A Longitudinal Cohort Study.

    PubMed

    Hashizume, Cary T; Woloschuk, Wayne; Hecker, Kent G

    2015-01-01

    There is a paucity of research regarding veterinary students' attitudes toward the rural environment and rural veterinary practice and how these attitudes might change over the course of a veterinary medicine program that includes rural clinical experience. Using a 23-item questionnaire, attitudes toward rural lifestyle, rural work-life balance, opportunities for career and skill development in rural veterinary practice, and inter-professional teamwork in the rural environment were assessed at the beginning and completion of a four-year veterinary medicine program. Eighty-six students (74.4% female) were included in this Canadian study over a six-year period. Thirty-one participants (36.1%) were rural students. Overall, students' attitudes toward the rural lifestyle, rural work-life balance, and inter-professional teamwork in rural veterinary practice all significantly decreased (p<.001) over the course of the program. As compared to urban students, rural students had significantly higher rural lifestyle scores at both the beginning (p<.001) and end (p<.01) of the veterinary medicine program. A less positive attitude toward living and working in a rural environment could influence students to exclude rural veterinary practice as a career choice. Rural clinical experiences designed to sustain or increase veterinary student interest in rural practice may not be sufficient to support positive rural attitudes. Given the demand for rural veterinary services in developed countries, the implications of this study may extend beyond Canada.

  5. Longitudinal measures of perfluoroalkyl substances (PFAS) in serum of Gullah African Americans in South Carolina: 2003–2013

    PubMed Central

    Gribble, Matthew O.; Bartell, Scott M.; Kannan, Kurunthachalam; Wu, Qian; Fair, Patricia A.; Kamen, Diane L.

    2015-01-01

    Background Charleston Harbor has elevated concentrations of PFAS in dolphins, but local human exposure data are limited. Objectives We sought to describe PFAS serum concentrations’ temporal trends among Gullah African American residents of coastal South Carolina. Methods Longitudinal measures of PFAS in blood serum from a Gullah clinical sample, without lupus, were examined using spaghetti plots and visit-to-visit change scores (e.g., differences in concentrations between visits) among the 68 participants with repeated measures available. We also modeled population-level trends among the 71 participants with any data using proportionate percentile models, accounting for clustering through robust standard errors. In a post-hoc analysis we examined heterogeneity of temporal trends by age through mixed-effects models for the log-transformed PFAS compounds. Results Population concentrations of PFOS dropped approximately 9 (95% CI: 8, 10) percent each year over 2003–2013. This was concordant with individual PFOS trajectories (median PFOS change score −21.7 ng/g wet weight, interquartile range of PFOS change scores: −32.8, −14.9) and reports for other populations over this time period. Several other compounds including PFOA, PFHxS, and PFuNDA also showed a population-level decrease. However, examination of individual trajectories suggested substantial heterogeneity. Post-hoc analyses indicated that PFAS trajectories were heterogeneous by age. Conclusions Many PFAS compounds are decreasing in a sample of Gullah African Americans from coastal South Carolina. There may be age differences in the elimination kinetics of PFASs. The possible role of age as a modifier of PFAS serum trends merits further research. PMID:25819541

  6. Incentivised chronic disease management and the inverse equity hypothesis: findings from a longitudinal analysis of Scottish primary care practice-level data.

    PubMed

    Lowrie, Richard; McConnachie, Alex; Williamson, Andrea E; Kontopantelis, Evangelos; Forrest, Marie; Lannigan, Norman; Mercer, Stewart W; Mair, Frances S

    2017-04-11

    The inverse equity hypothesis asserts that new health policies initially widen inequality, then attenuate inequalities over time. Since 2004, the UK's pay-for-performance scheme for chronic disease management (CDM) in primary care general practices (the Quality and Outcomes Framework) has permitted practices to except (exclude) patients from attending annual CDM reviews, without financial penalty. Informed dissent (ID) is one component of exception rates, applied to patients who have not attended due to refusal or non-response to invitations. 'Population achievement' describes the proportion receiving care, in relation to those eligible to receive it, including excepted patients. Examination of exception reporting (including ID) and population achievement enables the equity impact of the UK pay-for-performance contract to be assessed. We conducted a longitudinal analysis of practice-level rates and of predictors of ID, overall exceptions and population achievement for CDM to examine whether the inverse equity hypothesis holds true. We carried out a retrospective, longitudinal study using routine primary care data, analysed by multilevel logistic regression. Data were extracted from 793 practices (83% of Scottish general practices) serving 4.4 million patients across Scotland from 2010/2011 to 2012/2013, for 29 CDM indicators covering 11 incentivised diseases. This provided 68,991 observations, representing a total of 15 million opportunities for exception reporting. Across all observations, the median overall exception reporting rate was 7.0% (7.04% in 2010-2011; 7.02% in 2011-2012 and 6.92% in 2012-2013). The median non-attendance rate due to ID was 0.9% (0.76% in 2010-2011; 0.88% in 2011-2012 and 0.96% in 2012-2013). Median population achievement was 83.5% (83.51% in 2010-2011; 83.41% in 2011-2012 and 83.63% in 2012-2013). The odds of ID reporting in 2012/2013 were 16.0% greater than in 2010/2011 (p < 0.001). Practices in Scotland's most deprived communities

  7. Spot-checks to measure general hygiene practice.

    PubMed

    Sonego, Ina L; Mosler, Hans-Joachim

    2016-01-01

    A variety of hygiene behaviors are fundamental to the prevention of diarrhea. We used spot-checks in a survey of 761 households in Burundi to examine whether something we could call general hygiene practice is responsible for more specific hygiene behaviors, ranging from handwashing to sweeping the floor. Using structural equation modeling, we showed that clusters of hygiene behavior, such as primary caregivers' cleanliness and household cleanliness, explained the spot-check findings well. Within our model, general hygiene practice as overall concept explained the more specific clusters of hygiene behavior well. Furthermore, the higher general hygiene practice, the more likely children were to be categorized healthy (r = 0.46). General hygiene practice was correlated with commitment to hygiene (r = 0.52), indicating a strong association to psychosocial determinants. The results show that different hygiene behaviors co-occur regularly. Using spot-checks, the general hygiene practice of a household can be rated quickly and easily.

  8. Middle-class African American adolescents' and parents' conceptions of parental authority and parenting practices: a longitudinal investigation.

    PubMed

    Smetana, J G

    2000-01-01

    Conceptions of parental authority and ratings of parental rules and decision making were examined longitudinally among 82 middle-class African American adolescents and their parents (82 mothers and 52 fathers), who were divided into two groups according to family income. Adolescents were, on average, 13.14 years of age at Time 1 and 15.05 years of age at Time 2. Nearly all adolescents and parents affirmed parents' legitimate authority to regulate (and children's obligation to comply with) rules regarding moral, conventional, prudential, friendship, and multifaceted issues, but they were more equivocal in their judgments regarding personal issues. With age, adolescents increasingly judged personal issues to be beyond the bounds of legitimate parental authority, but judgments differed by family income. Adolescents from upper income families rejected parents' legitimate authority to regulate personal issues more at Time 1 than did adolescents from middle income families, but no differences were found at Time 2. Authority to regulate adolescents' behavior did not extend to other adults or to schools, churches, and the law. With adolescents' increasing age, African American families became less restrictive in regulating prudential, friendship, multifaceted, and personal issues. Adolescents', mothers', and fathers' judgments demonstrated significant continuity over time, but few cross- or within-generation associations in judgments were found. Conceptions of legitimate parental authority at Time 1 were found to predict family rules at Time 2.

  9. Middle cerebral artery blood flow velocities and pulsatility index and the cerebroplacental pulsatility ratio: longitudinal reference ranges and terms for serial measurements.

    PubMed

    Ebbing, C; Rasmussen, S; Kiserud, T

    2007-09-01

    To establish reference ranges suitable for serial assessments of the fetal middle cerebral (MCA) and umbilical (UA) artery blood flow velocities, pulsatility index (PI) and cerebroplacental pulsatility ratio and to provide terms for calculating conditional reference intervals suitable for individual serial measurements. This was a longitudinal study of 161 singleton pregnancies. Using Doppler ultrasound, MCA and UA blood velocities and PI were determined three to five times at 3-5-week intervals over a gestational age range of 19-41 weeks. Polynomial regression lines for the 95th, 50th and 5th percentiles were calculated for the peak systolic velocity (PSV), time-averaged maximum velocity (TAMXV), PI and cerebroplacental ratio. Terms for calculating conditional reference intervals were established. Based on 566 observations our new longitudinal reference ranges for fetal middle cerebral PSV, TAMXV and PI provided terms for calculating conditional reference intervals (i.e. predicting expected 95% confidence limits based on a previous measurement), and correspondingly for the cerebroplacental ratio (n = 550). The reference ranges were at some variance with those of previous cross-sectional studies. The narrow 95% confidence limits for the 5(th) and 95(th) percentiles ensured reliable ranges. We have established longitudinal reference ranges appropriate for the serial assessment of MCA blood velocities and PI and cerebroplacental ratio. Particularly the terms for calculating conditional ranges based on a previous observation make this system more appropriate for longitudinal monitoring than are cross-sectional data. Copyright 2007 ISUOG. Published by John Wiley & Sons, Ltd.

  10. Capturing Quality in Formative Assessment Practice: Measurement Challenges. CRESST Report 770

    ERIC Educational Resources Information Center

    Herman, Joan L.; Osmundson, Ellen; Silver, David

    2010-01-01

    This study examines measures of formative assessment practice using data from a study of the implementation and effects of adding curriculum embedded measures to a hands-on science program for upper elementary school students. The authors present a unifying conception for measuring critical elements of formative assessment practice, illustrate…

  11. Healthcare improvement as planned system change or complex responsive processes? a longitudinal case study in general practice

    PubMed Central

    2013-01-01

    Background Interest in how to implement evidence-based practices into routine health care has never been greater. Primary care faces challenges in managing the increasing burden of chronic disease in an ageing population. Reliable prescriptions for translating knowledge into practice, however, remain elusive, despite intense research and publication activity. This study seeks to explore this dilemma in general practice by challenging the current way of thinking about healthcare improvement and asking what can be learned by looking at change through a complexity lens. Methods This paper reports the local level of an embedded case study of organisational change for better chronic illness care over more than a decade. We used interviews, document review and direct observation to explore how improved chronic illness care developed in one practice. This formed a critical case to compare, using pattern matching logic, to the common prescription for local implementation of best evidence and a rival explanation drawn from complexity sciences interpreted through modern sociology and psychology. Results The practice changed continuously over more than a decade to deliver better chronic illness care in line with research findings and policy initiatives – re-designing care processes, developing community linkages, supporting patient self-management, using guidelines and clinical information systems, and integrating nurses into the practice team. None of these improvements was designed and implemented according to an explicit plan in response to a documented gap in chronic disease care. The process that led to high quality chronic illness care exhibited clear complexity elements of co-evolution, non-linearity, self-organisation, emergence and edge of chaos dynamics in a network of agents and relationships where a stable yet evolving way of organizing emerged from local level communicative interaction, power relating and values based choices. Conclusions The current discourse

  12. Healthcare improvement as planned system change or complex responsive processes? a longitudinal case study in general practice.

    PubMed

    Booth, Barbara J; Zwar, Nicholas; Harris, Mark F

    2013-04-23

    Interest in how to implement evidence-based practices into routine health care has never been greater. Primary care faces challenges in managing the increasing burden of chronic disease in an ageing population. Reliable prescriptions for translating knowledge into practice, however, remain elusive, despite intense research and publication activity. This study seeks to explore this dilemma in general practice by challenging the current way of thinking about healthcare improvement and asking what can be learned by looking at change through a complexity lens. This paper reports the local level of an embedded case study of organisational change for better chronic illness care over more than a decade. We used interviews, document review and direct observation to explore how improved chronic illness care developed in one practice. This formed a critical case to compare, using pattern matching logic, to the common prescription for local implementation of best evidence and a rival explanation drawn from complexity sciences interpreted through modern sociology and psychology. The practice changed continuously over more than a decade to deliver better chronic illness care in line with research findings and policy initiatives--re-designing care processes, developing community linkages, supporting patient self-management, using guidelines and clinical information systems, and integrating nurses into the practice team. None of these improvements was designed and implemented according to an explicit plan in response to a documented gap in chronic disease care. The process that led to high quality chronic illness care exhibited clear complexity elements of co-evolution, non-linearity, self-organisation, emergence and edge of chaos dynamics in a network of agents and relationships where a stable yet evolving way of organizing emerged from local level communicative interaction, power relating and values based choices. The current discourse of implementation science as planned

  13. Measuring prescribing practices in a state mental hospital system.

    PubMed

    Hartmann, K; Allison, J; Hartig, P

    1979-07-01

    To determine the degree to which Nebraska's three state mental hospitals complied with recognized guidelines for prescription of psychotropic medications, a study was made for 1326 drug orders issued over a five-year period. The prescribing practices in the hospital were then reviewed in relation to the guidelines in areas of polypharmacy, daily dose frequency, time of day, use of p.r.n. orders, drug form, dosages for children and the elderly, dosages during acute and stabilized stages of illness, and brand versus generic names. The study highlighted areas of progress in drug use practices and identified areas for improvement.

  14. Semi-Spontaneous Oral Text Production: Measurements in Clinical Practice

    ERIC Educational Resources Information Center

    Lind, Marianne; Kristoffersen, Kristian Emil; Moen, Inger; Simonsen, Hanne Gram

    2009-01-01

    Functionally relevant assessment of the language production of speakers with aphasia should include assessment of connected speech production. Despite the ecological validity of everyday conversations, more controlled and monological types of texts may be easier to obtain and analyse in clinical practice. This article discusses some simple…

  15. Measuring Data Use Beliefs and Practices in Early Education Settings

    ERIC Educational Resources Information Center

    Stein, Amanda; Connors, Maia C.

    2016-01-01

    Educare is a network of enhanced Early Head Start (EHS)/Head Start (HS) (birth to age 5) programs that implement innovative Research-Program Partnerships (RPPs) to engage researchers, program leaders, staff, and at times, other stakeholders in a collaborative approach to supporting data use practices for decision-making and continuous quality…

  16. Measuring Effectiveness in Transfer Practices for Adult Learners

    ERIC Educational Resources Information Center

    Dougherty, B. Christopher

    2009-01-01

    The Research to Practice (RTP) column in "The Journal of Continuing Higher Education" has recently focused on evaluation methods that continuing education (CE) units can utilize, reports on surveys of CE practitioners, and recommendations for research on dynamics that impact CE programs and the students enrolling in them. In this article, the…

  17. Semi-Spontaneous Oral Text Production: Measurements in Clinical Practice

    ERIC Educational Resources Information Center

    Lind, Marianne; Kristoffersen, Kristian Emil; Moen, Inger; Simonsen, Hanne Gram

    2009-01-01

    Functionally relevant assessment of the language production of speakers with aphasia should include assessment of connected speech production. Despite the ecological validity of everyday conversations, more controlled and monological types of texts may be easier to obtain and analyse in clinical practice. This article discusses some simple…

  18. Impact of air pollution on pulmonary function and respiratory symptoms in children. Longitudinal repeated-measures study

    PubMed Central

    2010-01-01

    Background Salamanca, Mexico occupied fourth place nationally in contaminating emissions. The aim of the study was to determine the impact of air pollution on the frequency of pulmonary function alterations and respiratory symptoms in school-age children in a longitudinal repeated-measures study. Methods We recruited a cohort of 464 children from 6 to 14 years of age, from two schools differing in distance from the major stationary air pollution sources. Spirometry, respiratory symptoms and air pollutants (O3, SO2, NO, NO2, NOx, PM10,) were obtained for each season. Mixed models for continuous variables and multilevel logistic regression for respiratory symptoms were fitted taking into account seasonal variations in health effects according to air pollution levels. Results Abnormalities in lung function and frequency of respiratory symptoms were higher in the school closer to major stationary air pollution sources than in the distant school. However, in winter differences on health disappeared. The principal alteration in lung function was the obstructive type, which frequency was greater in those students with greater exposure (10.4% vs. 5.3%; OR = 1.95, 95% CI 1.0-3.7), followed by the mixed pattern also more frequent in the same students (4.1% vs. 0.9%; OR = 4.69, 95% CI, 1.0-21.1). PM10 levels were the most consistent factor with a negative relationship with FVC, FEV1 and PEF but with a positive relationship with FEV1/FVC coefficient according to its change per 3-month period. Conclusions Students from the school closer to major stationary air pollution sources had in general more respiratory symptoms than those from the distant school. However, in winter air pollution was generalized in this city and differences in health disappeared. PM10 levels were the most consistent factor related to pulmonary function according, to its change per 3-month period. PMID:21106102

  19. The Increase in Longitudinally Measured Sleepiness Across Adolescence is Related to the Maturational Decline In Low-Frequency EEG Power

    PubMed Central

    Campbell, Ian G.; Higgins, Lisa M.; Trinidad, Jeffrey M.; Richardson, Pamela; Feinberg, Irwin

    2007-01-01

    longitudinally measured sleepiness across adolescence is related to the maturational decline in low-frequency EEG power. SLEEP 2007;30(12):1677-1687. PMID:18246977

  20. Practical management measures for patients with recurrent herpes labialis.

    PubMed

    St Pierre, S A; Bartlett, B L; Schlosser, B J

    2009-01-01

    Recurrent herpes labialis (RHL) is a common condition associated with the formation of vesicles around the mouth, often preceded by prodromal symptoms including tingling and burning. Treatment is targeted toward individual episodes, but in severe cases, suppressive therapy may be indicated. At present, no cure exists for this troublesome condition. The purpose of this article is to serve as a practical guide in the management of RHL by summarizing current treatments and discussing potential new therapies.

  1. A Proposed Conceptual Model to Measure Unwarranted Practice Variation

    DTIC Science & Technology

    2007-05-03

    or themes . Coding of data will assist the researcher in discovering the themes of the actual variables of the model. We expect the data to focus on... themes . This method of validation is perhaps the easiest and most important strategy for a project that relies heavily on Unwarranted Practice...Variation 15 literature review as a basis for theoretical model building. Multiple sources proffering similar themes will be sought as justification for the

  2. Identifying best practice through benchmarking and outcome measurement.

    PubMed

    Lanier, Lynne

    2004-01-01

    Collecting and analyzing various types of data are essential to identifying areas for improvement. Data collection and analysis are routinely performed in hospitals and are even required by some regulatory agencies. Realization of the full benefits, which may be achieved through collection and analysis of data, should be actively pursued to prevent a meaningless exercise in paperwork. Internal historical comparison of data may be helpful but does not achieve the ultimate goal of identifying external benchmarks in order to determine best practice. External benchmarks provide a means of comparison with similar facilities, allowing the identification of processes needing improvement. The specialty of ophthalmology presents unique practice situations that are not comparable with other specialties, making it imperative to benchmark against other facilities where quick surgical case time, efficient surgical turnover times, low infection rates, and cost containment are essential and standard operations. Important data to benchmark include efficiency data, financial data, and quality or patient outcome data. After identifying facilities that excel in certain aspects of performance, it is necessary to analyze how their procedures help them achieve these favorable results. Careful data collection and analysis lead to improved practice and patient care.

  3. Longitudinal changes in objectively measured sedentary behaviour and their relationship with adiposity in children and adolescents: systematic review and evidence appraisal.

    PubMed

    Tanaka, C; Reilly, J J; Huang, W Y

    2014-10-01

    This review aimed to determine longitudinal changes in objectively measured overall sedentary behaviour, and to examine their associations with adiposity in children and adolescents. A search for longitudinal studies was performed using several electronic databases. Of 161 potentially eligible papers, 10 for change in sedentary behaviour and 3 for longitudinal associations with change in adiposity were included. Weighted mean increase in daily sedentary behaviour per year was 5.7% for boys and 5.8% for girls. Only one paper included preschool children, and it showed a decrease in sedentary behaviour. Nine studies were from Western countries. Null associations were reported between sedentary behaviour and adiposity in two studies, the other found that increases in sedentary behaviour were associated with increases in adiposity, but only in those with body mass index above the 50th percentile. There was consistent evidence that sedentary behaviour increases with age in school-age children and adolescents, by approximately 30 min extra daily sedentary behaviour per year. There was little evidence on the influence of changes in sedentary behaviour on changes in adiposity. There is a need for more longitudinal research, for more evidence from outside the Western world, and for more studies that examine 'dose-response' associations between changes in sedentary behaviour and changes in adiposity.

  4. Practical clinical trials for translating research to practice: design and measurement recommendations.

    PubMed

    Glasgow, Russell E; Magid, David J; Beck, Arne; Ritzwoller, Debra; Estabrooks, Paul A

    2005-06-01

    There is a pressing need for practical clinical trials (PCTs) that are more relevant to clinicians and decision-makers, but many are unaware of these trials. Furthermore, such trials can be challenging to conduct and to report. The objective of this study was to build on the seminal paper by Tunis et al (Practical clinical trials. Increasing the value of clinical research for decision making in clinical and health policy. JAMA. 2003;290:1624-1632.) and to provide recommendations and examples of how practical clinical trials can be conducted and the results reported to enhance external validity without sacrificing internal validity. We discuss evaluating practical intervention options, alternative research designs, representativeness of samples participating at both the patient and the setting/clinician level, and the need for multiple outcomes to address clinical and policy implications. We provide a set of specific recommendations for issues to be reported in PCTs to increase their relevance to clinicians and policymakers, and to help reduce the gap between research and practice.

  5. A study on the longitudinal momentum modulation of low energy heavy ion beam bunches with time-resolved beam profile measurement

    NASA Astrophysics Data System (ADS)

    Liu, Xingguang; Yoshimoto, Takashi

    2017-10-01

    The longitudinal momentum modulation can be studied with time-resolved beam profiles measured at a region where an appropriate value of the dispersion function exists. In this paper, momentum modulation of two different beam lengths and their mechanisms are discussed. The modulation for a four-millisecond beam comes from beam loading effects at the extraction region of an Electron Cyclotron Resonance Ion Source (ECRIS) and the post-acceleration column after the ECRIS. In the case of a four-microsecond beam bunch, it comes from the transitional chopping process of the Einzel Lens Chopper. These results obtained confirmed the usefulness and effectiveness of the time-resolved profile measurement in studying the longitudinal momentum modulation.

  6. The CEDAR Study: A Longitudinal Study of the Clinical Effects of Conventional DMARDs and Biologic DMARDs in Australian Rheumatology Practice

    PubMed Central

    Tymms, Kathleen; de Jager, Julien; Griffiths, Hedley; Nicholls, Dave; Bird, Paul; Young, Jennifer; Hill, Julie; Zochling, Jane

    2017-01-01

    Objectives To observe the choices of conventional disease modifying antirheumatic drugs (cDMARDs) and biologic DMARDs (bDMARDs) in the management of rheumatoid arthritis (RA) in Australian routine clinical practice, to assess treatment survival and determine the effect of cDMARDs/bDMARDs on disease activity. Methods Routinely collected, deidentified clinical data was sourced from 20 Australian rheumatology practices. RA patients aged ≥18 years, who had received cDMARDs/bDMARDs and a recorded subsequent visit, were included. A linear mixed model was used to determine the change over time and the percentage reduction in disease activity was summarized. Results 12,526 RA patients were included: 72% females, mean age 62 years. cDMARDs and bDMARDs were used in 92% and 30% of patients, respectively. The most commonly prescribed cDMARD was methotrexate (76% patients); median time to stopping treatment was 337 months [95% CI: 279–ND]. Etanercept was the most commonly prescribed bDMARD (12% patients); median time to stopping treatment was 79 months [95% CI: 57–93]. Of 5,341 patients with a first change in medication (cDMARD or bDMARD), 87% had therapy escalation and 13% deescalation. Reduction in DAS28-ESR, 6-month post-DMARDs initiation ranged from 3%, adalimumab, to 14%, leflunomide and tocilizumab. Conclusions In this large Australian cohort of unselected community RA patients, the choices of cDMARDs/bDMARDs are aligned with current international guidelines. PMID:28630629

  7. Some Better Practices for Measuring Racial and Ethnic Identity Constructs

    ERIC Educational Resources Information Center

    Helms, Janet E.

    2007-01-01

    Racial and ethnic identity (REI) measures are in danger of becoming conceptually meaningless because of evaluators' insistence that they conform to measurement models intended to assess unidimensional constructs, rather than the multidimensional constructs necessary to capture the complexity of internalized racial or cultural socialization. Some…

  8. How Much Is Too Much? Multiple Measures in Practice.

    ERIC Educational Resources Information Center

    Hohn, Alisabeth M.; Veitch, William R.

    This paper describes the experiences of Colorado Springs School District Eleven in using multiple measures to determine if third graders were reading at "grade level." The use of multiple measures may be threatened by the rapidly increasing pressures about assessment and accountability in Colorado that teachers are beginning to feel that…

  9. Redefining perioperative advanced practice. Scope of practice: measuring impact and sustainability.

    PubMed

    Radford, Mark; Abbassi, Ann; Williamson, Alastair; Johnston, Paul

    2003-12-01

    There are increasing demands placed upon the modern NHS, particularly in emergency care. In combating these demands, new approaches to practice will form an overall strategy for improving care delivered to patients. This is the second in a series by authors from the Good Hope Hospital NHS Trust and explains their experience of developing an innovative approach to the management of surgical emergencies through the specialist nurse role in anaesthesia and emergency surgery. It examines the scope of practice, clinical and operational impact of the role, and future developments.

  10. Exploring the beliefs and practices of five preservice secondary science teachers from recruitment through induction in a university preparation program: A longitudinal study

    NASA Astrophysics Data System (ADS)

    Fletcher, Steven Samuel

    This three-year longitudinal study explores the evolving beliefs and practices of five prospective secondary science teachers in a university preparation program from recruitment through their first year in the classroom. As an interpretive qualitative study, the format for data collection and analysis utilizes a case-study methodology with cross-case analysis. Data was collected through semi-structured interviews, collected artifacts, and classroom observations. There are a number of important conclusions from this study. First, the teachers' beliefs about teaching initially shift to a contemporary focus during the program, but ultimately return to a didactic orientation by their first year in the classroom. At the same time, the teachers' beliefs about learning remain consistently more contemporary in nature. Second, the participants believe that they practice teaching science as inquiry at a higher level than are indicated by researcher observations. Third, while participants value advanced content and educational theory coursework, they do not always see the link between these experiences and their development as science teachers. Fourth, the findings from this study reveal that internal and external contextual factors impacted, to varying degrees, the development of the science teachers. The findings from this study contribute to a deeper understanding of the development of science teachers from preservice education to the induction years, which indicates a pattern that is not linear. The findings from this study also reinforce the importance of internal and external contextual factors on the development of science teachers. Ultimately, this study is important to the field of secondary science teacher education as it depicts the complex interactions between the individual, the preparation program, and the school placements that impact the beliefs and practices of preservice and beginning teachers.

  11. Current assessment practice, personality measurement, and rorschach usage by psychologists.

    PubMed

    Musewicz, John; Marczyk, Geoffrey; Knauss, Linda; York, David

    2009-09-01

    In this study, we investigated current personality assessment practice and attitudes toward Rorschach (Exner, 2003) usage by 215 psychologists. We administered an Internet survey to members of the Society for Personality Assessment (SPA) and the American Psychological Association. Results were similar to those of past surveys, but the importance of using tests with strong psychometric properties was greater in this study. The majority of respondents reported using the Rorschach and supporting efforts to standardize and psychometrically validate the test. However, SPA members agreed more strongly than non-SPA members that the Rorschach is an effective test. Implications and directions for future research are discussed.

  12. Practical Measurement and Productive Persistence: Strategies for Using Digital Learning System Data to Drive Improvement

    ERIC Educational Resources Information Center

    Krumm, Andrew E.; Beattie, Rachel; Takahashi, Sola; D'Angelo, Cynthia; Feng, Mingyu; Cheng, Britte

    2016-01-01

    This paper outlines the development of practical measures of productive persistence using digital learning system data. Practical measurement refers to data collection and analysis approaches originating from improvement science; productive persistence refers to the combination of academic and social mindsets as well as learning behaviours that…

  13. Optimizing PiB-PET SUVR change-over-time measurement by a large-scale analysis of longitudinal reliability, plausibility, separability, and correlation with MMSE.

    PubMed

    Schwarz, Christopher G; Senjem, Matthew L; Gunter, Jeffrey L; Tosakulwong, Nirubol; Weigand, Stephen D; Kemp, Bradley J; Spychalla, Anthony J; Vemuri, Prashanthi; Petersen, Ronald C; Lowe, Val J; Jack, Clifford R

    2017-01-01

    Quantitative measurements of change in β-amyloid load from Positron Emission Tomography (PET) images play a critical role in clinical trials and longitudinal observational studies of Alzheimer's disease. These measurements are strongly affected by methodological differences between implementations, including choice of reference region and use of partial volume correction, but there is a lack of consensus for an optimal method. Previous works have examined some relevant variables under varying criteria, but interactions between them prevent choosing a method via combined meta-analysis. In this work, we present a thorough comparison of methods to measure change in β-amyloid over time using Pittsburgh Compound B (PiB) PET imaging.

  14. Measurement of inclusive cross sections at high at and 252 GeV and of the longitudinal proton structure function at HERA

    NASA Astrophysics Data System (ADS)

    Andreev, V.; Baghdasaryan, A.; Baghdasaryan, S.; Begzsuren, K.; Belousov, A.; Belov, P.; Boudry, V.; Bradt, G.; Brinkmann, M.; Brisson, V.; Britzger, D.; Buniatyan, A.; Bylinkin, A.; Bystritskaya, L.; Campbell, A. J.; Cantun Avila, K. B.; Ceccopieri, F.; Cerny, K.; Chekelian, V.; Contreras, J. G.; Dainton, J. B.; Daum, K.; De Wolf, E. A.; Diaconu, C.; Dobre, M.; Dodonov, V.; Dossanov, A.; Dubak, A.; Eckerlin, G.; Egli, S.; Elsen, E.; Favart, L.; Fedotov, A.; Feltesse, J.; Ferencei, J.; Fleischer, M.; Fomenko, A.; Gabathuler, E.; Gayler, J.; Ghazaryan, S.; Glazov, A.; Goerlich, L.; Gogitidze, N.; Gouzevitch, M.; Grab, C.; Grebenyuk, A.; Greenshaw, T.; Grindhammer, G.; Habib, S.; Haidt, D.; Henderson, R. C. W.; Herbst, M.; Hildebrandt, M.; Hladkỳ, J.; Hoffmann, D.; Horisberger, R.; Hreus, T.; Huber, F.; Jacquet, M.; Janssen, X.; Jung, A. W.; Jung, H.; Kapichine, M.; Kiesling, C.; Klein, M.; Kleinwort, C.; Kogler, R.; Kostka, P.; Kretzschmar, J.; Krüger, K.; Landon, M. P. J.; Lange, W.; Laycock, P.; Lebedev, A.; Levonian, S.; Lipka, K.; List, B.; List, J.; Lobodzinski, B.; Lubimov, V.; Malinovski, E.; Martyn, H.-U.; Maxfield, S. J.; Mehta, A.; Meyer, A. B.; Meyer, H.; Meyer, J.; Mikocki, S.; Morozov, A.; Müller, K.; Naumann, Th.; Newman, P. R.; Niebuhr, C.; Nowak, G.; Nowak, K.; Olivier, B.; Olsson, J. E.; Ozerov, D.; Pahl, P.; Pascaud, C.; Patel, G. D.; Perez, E.; Petrukhin, A.; Picuric, I.; Pirumov, H.; Pitzl, D.; Plačakytė, R.; Pokorny, B.; Polifka, R.; Radescu, V.; Raicevic, N.; Raspereza, A.; Ravdandorj, T.; Reimer, P.; Rizvi, E.; Robmann, P.; Roosen, R.; Rostovtsev, A.; Rotaru, M.; Rusakov, S.; Šálek, D.; Sankey, D. P. C.; Sauter, M.; Sauvan, E.; Schmitt, S.; Schoeffel, L.; Schöning, A.; Schultz-Coulon, H.-C.; Sefkow, F.; Shushkevich, S.; Soloviev, Y.; Sopicki, P.; South, D.; Spaskov, V.; Specka, A.; Steder, M.; Stella, B.; Straumann, U.; Sykora, T.; Thompson, P. D.; Traynor, D.; Truöl, P.; Tsakov, I.; Tseepeldorj, B.; Turnau, J.; Valkárová, A.; Vallée, C.; Van Mechelen, P.; Vazdik, Y.; Wegener, D.; Wünsch, E.; Žáček, J.; Zhang, Z.; Žlebčík, R.; Zohrabyan, H.; Zomer, F.

    2014-04-01

    Inclusive double differential cross sections for neutral current deep inelastic scattering are measured with the H1 detector at HERA. The data were taken with a lepton beam energy of GeV and two proton beam energies of and 575 GeV corresponding to centre-of-mass energies of 225 and 252 GeV, respectively. The measurements cover the region of for GeV up to . The measurements are used together with previously published H1 data at GeV and lower data at , and GeV to extract the longitudinal proton structure function in the region GeV.

  15. Impact of college-administered quality practice assessments: a longitudinal evaluation of repeat peer assessments of continuing competence in physiotherapists.

    PubMed

    Norman, Kathleen E; O'Donovan, Mary Jane; Campbell, Fiona

    2015-01-01

    Objet: L'Ordre des physiothérapeutes de l'Ontario (OPO) a élaboré son processus d'évaluation de la pratique par les pairs en vertu d'exigences réglementaires relatives à l'assurance de la qualité. Chaque année, un petit pourcentage de physiothérapeutes, pour la plupart sélectionnés au hasard, font l'objet d'une évaluation de la pratique. Afin de jeter la lumière sur le maintien des compétences, nous rendons compte des résultats des physiothérapeutes qui ont subi deux évaluations de la pratique. Méthodes: On a extrait les dossiers des physiothérapeutes ayant subi deux évaluations de la pratique non connexes. On a ensuite examiné les caractéristiques démographiques, les notes des pairs-évaluateurs et les décisions qui en ont découlé. Les résultats ont fait l'objet d'un examen transversal (comparaison avec d'autres évaluations de la pratique effectuées au cours de la même période) et d'un examen longitudinal (dans la cohorte). Résultats: Entre 2004 et 2012, 117 physiothérapeutes de l'Ontario ont subi deux évaluations de la pratique non connexes, habituellement à un intervalle de 5 à 7 ans. Cette cohorte était représentative des physiothérapeutes de l'Ontario pour ce qui est des rapports de masculinité, des études et des années de pratique. À la première évaluation de la pratique, les résultats de cette cohorte étaient semblables à ceux des autres physiothérapeutes; à la deuxième évaluation, ils étaient meilleurs que les résultats des autres physiothérapeutes ayant subi une première évaluation de la pratique au cours de la même période (p=0,02). Les résultats de la cohorte étaient meilleurs à la deuxième évaluation de la pratique qu'à la première (p<0,001). Conclusions: Les physiothérapeutes sont susceptibles de répondre aux normes professionnelles à l'occasion d'une deuxième évaluation de la pratique effectuée 5 à 7 ans après la première évaluation. Des recherches supplémentaires s

  16. Beta fields and measurement practices at DOE facilities

    NASA Astrophysics Data System (ADS)

    Swinth, K. L.; Rathbun, L. A.; Brackenbush, L. W.

    1985-09-01

    As part of a larger program, the beta measurement problem at DOE facilities was assessed through the use of a questionnaire and field visits to selected facilities. At 35% the facilities beta-emitting radionuclides can contribute enough to the radiation exposures that they must be considered in establishing protection requirements. Measurements were made in several facilities using scintillators, a surface barrier detector plus various dosimeters and survey instruments. Beta dose rates of several hundred mrad/hr were not unusual and beta:gamma ratios of greater than 30:1 were frequently observed. The agreement between the various measurement techniques was frequently unacceptable.

  17. A longitudinal study of aspects of a hospital's family-centred nursing: changing practice through data translation.

    PubMed

    White, Chris; Wilson, Valerie

    2015-01-01

    To examine how results and data from multiple Family Centred Nursing Index surveys help the development of family-centred nursing at organizational and ward levels. A critical analysis of survey data. The Family Centred Nursing Index provides a valid and reliable assessment of aspects of nursing, through a comprehensive survey of traditional indicators of practice development and a broader range of aspects of practice. A survey with 113 questions, each to be answered on 7-point Likert scale conducted six times in the last 7 years. Surveys have been in 2006, 2008, 2009, 2010, 2011/2012 and 2012/2013. All nurses employed by the organization can participate. These are reported as means across 19 constructs linked to five key domains and their significance is examined by year and (in the clinical settings) and compared against the organizational (whole population) averages. Ongoing survey and analysis of nurses' views of their work is providing a valuable source of developmental data. The results show unexpected associations between constructs e.g. - a high level of work stress does not correlate with a lower level of job satisfaction (and vice versa). A clear historical picture of many elements of developing family-centred care is emerging at both the organizational and individual-ward levels. This study provides insights into aspects of organizational and wards working environment for nurses and how these aspects of nurses' work interact in unexpected ways. It is appropriate for providing information to organizations and ward teams in relation to their development towards family-centred cultures. © 2014 Commonwealth of Australia. Journal of Advanced Nursing © 2014 John Wiley & Sons Ltd.

  18. Practical new method of measuring thermal-neutron fluence

    NASA Technical Reports Server (NTRS)

    Siebold, J. R.; Warman, E. A.

    1967-01-01

    Thermoluminescence dosimeter technique measures thermal-neutron fluence by encapsulating lithium flouride phosphor powder and exposing it to a neutron environment. The capsule is heated in a dosimeter reader, which results in light emission proportional to the neutron fluence.

  19. Automating Performance Measures and Clinical Practice Guidelines: Differences and Complementarities

    PubMed Central

    Tu, Samson W.; Martins, Susana; Oshiro, Connie; Yuen, Kaeli; Wang, Dan; Robinson, Amy; Ashcraft, Michael; Heidenreich, Paul A.; Goldstein, Mary K.

    2016-01-01

    Through close analysis of two pairs of systems that implement the automated evaluation of performance measures (PMs) and guideline-based clinical decision support (CDS), we contrast differences in their knowledge encoding and necessary changes to a CDS system that provides management recommendations for patients failing performance measures. We trace the sources of differences to the implementation environments and goals of PMs and CDS. PMID:28269917

  20. Peace Operations in Mali: Theory into Practice Then Measuring Effectiveness

    DTIC Science & Technology

    2017-06-09

    Safe and Secure Environment, two objectives were measured. Objective #1 sought the Cessation of Large Scale Violence . Success was attained, as...force has not been created, and a troubling level of violence persists. 15. SUBJECT TERMS Peace Operations, Peacebuilding, Peacekeeping, Mali...measured. Objective #1 sought the Cessation of Large Scale Violence . Success was attained, as French military forces saved the Malian government from

  1. Observations, measurements and best practices for monitoring hydraulic redistribution

    NASA Astrophysics Data System (ADS)

    Davis, T. W.; Liang, X.

    2011-12-01

    Hydraulic redistribution (HR) is a biogeophysical phenomenon where plant roots move water through the soil column from areas of high soil moisture content to areas of low soil moisture content. The impacts of this process on the hydrologic cycle at the regional scale are beginning to be studied through the use of numerical modeling. The extent of plant species which exhibit HR, the magnitude of water redistributed and the conditions under which it occurs are still unknown. Therefore models must rely on some general assumptions to account for this process. More information is needed to understand how to correctly account for HR in land surface models. The ideal method is through direct measurement and observation. HR has been studied through a variety of mediums, e.g. deuterium footprints, soil moisture patterns and sap flow measurements. All three methods capture the moisture fluctuations within the soil layers via measurements of deuterium concentration, volumetric soil moisture content and root sap flow direction. The problem with deuterium labeling is that it does not allow for the persistent long term measurements over natural wetting and drying periods without additional irrigation. Sap flow measurements, despite having the ability to measure specific plant individuals' water dynamics, requires difficult access to the plant's root system which can be complex and difficult to sample. Soil moisture measurements can be made on a variety of sensor types and the installation is much less intensive. This study examines soil moisture measurements as a means for monitoring HR. Field observations in different regions of the United States utilizing different soil moisture sensor types (capacitance and reflectometer) are shown to exhibit similar diurnal soil moisture patterns common to the HR phenomenon. These observations are then compared and contrasted to model simulation results.

  2. Measures to step up practical use of scientific work discussed

    NASA Astrophysics Data System (ADS)

    Khodzhimatov, V.

    1983-10-01

    To achieve significant acceleration of scientific-technical progress and bring all sectors of the economy to the most advanced frontiers of science and technology was proposed as one of the paramount tasks of our time. Much was done by scientists of Uzbekistan for the development of the multisectorial economy of the republic and for the creation of progressive technology in industry, capital construction, and in agriculture, especially in cotton production. Every year scientific organizations complete and turn over for practical use more than 33 different development projects with an economic impact of more than 600 million rubles. Thanks to their introduction, technical equipmentation has grown, technological processes were improved, the volume of production has increased, and the quality of output has improved.

  3. Real-time evaluation of longitudinal peak systolic strain (speckle tracking measurement) in left and right ventricles of athletes.

    PubMed

    Stefani, Laura; Pedrizzetti, Gianni; De Luca, Alessio; Mercuri, Roberto; Innocenti, Gabriele; Galanti, Giorgio

    2009-04-08

    Strain, and particularly Longitudinal Peak Systolic Strain (LPSS), plays a role in investigating the segmental and overall contractility of the heart which is a particularly interesting feature in athletes in whom regular training determines several morphological and functional modifications in both the ventricles, that normally work at different loads. Speckle tracking techniques assess the LPSS of LV and RV from B-mode imaging in real time, with uniform accuracy in all segments, and can verify the possible dissimilar segmental contributions of the two chambers to overall myocardial contraction. The aim of the study is to quantify the LPSS in real time in both the ventricles in order to estimate any possible different deformation properties in them during a systolic period. 32 subjects (20 athletes and 18 controls) were submitted to a standard echocardiographic examination at rest and after a Hand Grip (HG) stress. From a four-chamber-view image, the LPSS parameter was measured with Speckle Tracking analysis in the basal and medium-apical segments of the two ventricles, at rest and after HG. In both athletes and controls, LPSS values were significantly higher in the RV of athletes (RV LPSS medium-apical -23.87 +/- 4.94; basalfreewall -25.04 +/- 4.12 at rest) and controls (RV LPSSmedium-apical -25.21 +/- 4.97; basalfreewall -28.69 +/- 4.62 at rest) than in the LV of both (athletes LV LPSS medium-apical -18.14 +/- 4.16; basallateralwall -16.05 +/- 12.32; controls medium-apical -18.81 +/- 2.64; basallateralwall -19.74 +/- 3.84) With the HG test a significant enhancement of the LPSS(with P < .05) in the medium-apical segments of LV and RV was evident, but only in athletes; there was no modification of the standard echo-parameters in either group. ST analysis is an easy method for investigating the contractility of the RV through deformation parameters, showing greater involvement of the RV than LV at rest. In athletes only, after isometric stress the two ventricles

  4. Measuring Organizational Attributes of Primary Care Practices: Development of a New Instrument

    PubMed Central

    Ohman-Strickland, Pamela A; John Orzano, A; Nutting, Paul A; Perry Dickinson, W; Scott-Cawiezell, Jill; Hahn, Karissa; Gibel, Michelle; Crabtree, Benjamin F

    2007-01-01

    Objective To develop an instrument to measure organizational attributes relevant for family practices using the perspectives of clinicians, nurses, and staff. Data Sources/Study Setting Clinicians, nurses, and office staff (n = 640) from 51 community family medicine practices. Design A survey, designed to measure a practices' internal resources for change, for use in family medicine practices was created by a multidisciplinary panel of experts in primary care research and health care organizational performance. This survey was administered in a cross-sectional study to a sample of diverse practices participating in an intervention trial. A factor analysis identified groups of questions relating to latent constructs of practices' internal resources for capacity to change. ANOVA methods were used to confirm that the factors differentiated practices. Data Collection The survey was administered to all staff from 51 practices. Principal Findings The factor analysis resulted in four stable and internally consistent factors. Three of these factors, “communication,” “decision-making,” and “stress/chaos,” describe resources for change in primary care practices. One factor, labeled “history of change,” may be useful in assessing the success of interventions. Conclusions A 21-item questionnaire can reliably measure four important organizational attributes relevant to family practices. These attributes can be used both as outcome measures as well as important features for targeting system interventions. PMID:17489913

  5. Measuring organizational attributes of primary care practices: development of a new instrument.

    PubMed

    Ohman-Strickland, Pamela A; John Orzano, A; Nutting, Paul A; Perry Dickinson, W; Scott-Cawiezell, Jill; Hahn, Karissa; Gibel, Michelle; Crabtree, Benjamin F

    2007-06-01

    To develop an instrument to measure organizational attributes relevant for family practices using the perspectives of clinicians, nurses, and staff. Clinicians, nurses, and office staff (n=640) from 51 community family medicine practices. A survey, designed to measure a practices' internal resources for change, for use in family medicine practices was created by a multidisciplinary panel of experts in primary care research and health care organizational performance. This survey was administered in a cross-sectional study to a sample of diverse practices participating in an intervention trial. A factor analysis identified groups of questions relating to latent constructs of practices' internal resources for capacity to change. ANOVA methods were used to confirm that the factors differentiated practices. The survey was administered to all staff from 51 practices. The factor analysis resulted in four stable and internally consistent factors. Three of these factors, "communication,"decision-making," and "stress/chaos," describe resources for change in primary care practices. One factor, labeled "history of change," may be useful in assessing the success of interventions. A 21-item questionnaire can reliably measure four important organizational attributes relevant to family practices. These attributes can be used both as outcome measures as well as important features for targeting system interventions.

  6. Theory and practice for measuring health care quality

    PubMed Central

    Berwick, Donald M.; Knapp, Marian Gilbert

    1987-01-01

    As competition, cost control, and new modes of delivery emerge in health care, there is a need to reexamine both the traditional definitions of health care quality and the methods by which it is measured. Industries other than health care have much to teach regarding the methods for obtaining, analyzing, and displaying data; techniques for problem identification, problem solving, and reassessment; and ideas about organizational factors that produce a high quality product or service. The Quality-of-Care Measurement Department at the Harvard Community Health Plan has built a program that draws from a distinguished health care quality assurance tradition and incorporates techniques that have been successful in other industries. PMID:10312319

  7. A Longitudinal Study of State Strategies and Policies to Accelerate Evidence-Based Practices in the Context of Systems Transformation

    PubMed Central

    Rieckmann, Traci; Abraham, Amanda; Zwick, Janet; Rasplica, Caitlin; McCarty, Dennis

    2015-01-01

    Objective To profile state agency efforts to promote implementation of three evidence-based practices (EBPs): screening and brief intervention (SBIRT), psychosocial interventions, and medication-assisted treatment (MAT). Data Sources/Study Setting Primary data collected from representatives of 50 states and the District of Columbia’s Single State Authorities from 2007 to 2009. Study Design/Data Collection The study used mixed methods, in-depth, semistructured interviews and quantitative surveys. Interviews assessed state and provider strategies to accelerate implementation of EBPs. Principal Findings Statewide implementation of psychosocial interventions and MAT increased significantly over 3 years. In the first two assessments, states that contracted directly with providers were more likely to link use of EBPs to reimbursement, and states with indirect contract, through counties and other entities, increased recommendations, and some requirements for provision of specific EBPs. The number of states using legislation as a policy lever to promote EBPs was unchanged. Conclusions Health care reform and implementation of parity in coverage increases access to treatment for alcohol and drug use. Science-based substance abuse treatment will become even more crucial as payers seek consistent quality of care. This study provides baseline data on service delivery, contracting, and financing as state agencies and treatment providers prepare for implementation of the Affordable Care Act. PMID:25532616

  8. Putting Measurement First: Understanding "Grit" in Educational Policy and Practice

    ERIC Educational Resources Information Center

    Peterson, Daniel

    2015-01-01

    Non-cognitive dispositions have recently become psychological constructs of interest in the education, economics, philosophy, sociology, and psychology literature. In this article, I draw the distinction between property-first and measurement-first approaches to understanding the meaning of a particular non-cognitive disposition theoretical term,…

  9. Putting Measurement First: Understanding "Grit" in Educational Policy and Practice

    ERIC Educational Resources Information Center

    Peterson, Daniel

    2015-01-01

    Non-cognitive dispositions have recently become psychological constructs of interest in the education, economics, philosophy, sociology, and psychology literature. In this article, I draw the distinction between property-first and measurement-first approaches to understanding the meaning of a particular non-cognitive disposition theoretical term,…

  10. MEASUREMENT OF HYDRAULIC CONDUCTIVITY DISTRIBUTIONS: A MANUAL OF PRACTICE

    EPA Science Inventory

    The ability of hydrologists to perform field measurements of aquifer hydraulic properties must be enhanced in order to significantly improve the capacity to solve groundwater contamination problems at Superfund and other sites. The primary purpose of this manual is to provide ne...

  11. 38 CFR 21.4275 - Practical training courses; measurement.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... or registered professional nurse will be measured on the basis of credit hours or clock hours of attendance, whichever is appropriate. The clock hours of attendance may include academic class time, clinical... clock hours of attendance per week whichever is appropriate. (c) Medical and dental specialty...

  12. 38 CFR 21.4275 - Practical training courses; measurement.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... or registered professional nurse will be measured on the basis of credit hours or clock hours of attendance, whichever is appropriate. The clock hours of attendance may include academic class time, clinical... clock hours of attendance per week whichever is appropriate. (c) Medical and dental specialty...

  13. 38 CFR 21.4275 - Practical training courses; measurement.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... or registered professional nurse will be measured on the basis of credit hours or clock hours of attendance, whichever is appropriate. The clock hours of attendance may include academic class time, clinical... clock hours of attendance per week whichever is appropriate. (c) Medical and dental specialty...

  14. ePortfolio as a Measure of Reflective Practice

    ERIC Educational Resources Information Center

    Parkes, Kelly A.; Dredger, Katie S.; Hicks, David

    2013-01-01

    This instructional article outlines the qualities of effective ePortfolios and how reflection and student growth is measured. Student exemplars and assessment rubrics show how, despite changing tools and evolving standards, sustained collaboration and student coaching yields reflective practitioners in content areas and in technological knowledge.…

  15. Using Assessment to Improve Practice: New Developments and Measures.

    ERIC Educational Resources Information Center

    Geron, Scott Miyake; And Others

    1997-01-01

    Theme issue contains 18 articles on (1) clients' role in assessment of the elderly in long-term care; (2) choosing assessment measures (physical, cognitive, quality-of-life, well-being, social support, multidimensional, culturally appropriate); and (3) making assessments useful (including using technology, assessment by telephone, and clinical…

  16. Measuring Motor Skill Learning--A Practical Application

    ERIC Educational Resources Information Center

    Kovacs, Christopher R.

    2008-01-01

    The assessment of fundamental motor skills in early learners is critical to the overall well-being and physical development of the students within the physical education setting. Olrich (2002) has suggested that any physical education program must be designed to assess both measures of physical fitness and fundamental motor skills in all students.…

  17. BOOK REVIEW: Evaluating the Measurement Uncertainty: Fundamentals and practical guidance

    NASA Astrophysics Data System (ADS)

    Lira, Ignacio

    2003-08-01

    Evaluating the Measurement Uncertainty is a book written for anyone who makes and reports measurements. It attempts to fill the gaps in the ISO Guide to the Expression of Uncertainty in Measurement, or the GUM, and does a pretty thorough job. The GUM was written with the intent of being applicable by all metrologists, from the shop floor to the National Metrology Institute laboratory; however, the GUM has often been criticized for its lack of user-friendliness because it is primarily filled with statements, but with little explanation. Evaluating the Measurement Uncertainty gives lots of explanations. It is well written and makes use of many good figures and numerical examples. Also important, this book is written by a metrologist from a National Metrology Institute, and therefore up-to-date ISO rules, style conventions and definitions are correctly used and supported throughout. The author sticks very closely to the GUM in topical theme and with frequent reference, so readers who have not read GUM cover-to-cover may feel as if they are missing something. The first chapter consists of a reprinted lecture by T J Quinn, Director of the Bureau International des Poids et Mesures (BIPM), on the role of metrology in today's world. It is an interesting and informative essay that clearly outlines the importance of metrology in our modern society, and why accurate measurement capability, and by definition uncertainty evaluation, should be so important. Particularly interesting is the section on the need for accuracy rather than simply reproducibility. Evaluating the Measurement Uncertainty then begins at the beginning, with basic concepts and definitions. The third chapter carefully introduces the concept of standard uncertainty and includes many derivations and discussion of probability density functions. The author also touches on Monte Carlo methods, calibration correction quantities, acceptance intervals or guardbanding, and many other interesting cases. The book goes

  18. Measuring solar reflectance - Part II: Review of practical methods

    SciTech Connect

    Levinson, Ronnen; Akbari, Hashem; Berdahl, Paul

    2010-09-15

    A companion article explored how solar reflectance varies with surface orientation and solar position, and found that clear sky air mass 1 global horizontal (AM1GH) solar reflectance is a preferred quantity for estimating solar heat gain. In this study we show that AM1GH solar reflectance R{sub g,0} can be accurately measured with a pyranometer, a solar spectrophotometer, or an updated edition of the Solar Spectrum Reflectometer (version 6). Of primary concern are errors that result from variations in the spectral and angular distributions of incident sunlight. Neglecting shadow, background and instrument errors, the conventional pyranometer technique can measure R{sub g,0} to within 0.01 for surface slopes up to 5:12 [23 ], and to within 0.02 for surface slopes up to 12:12 [45 ]. An alternative pyranometer method minimizes shadow errors and can be used to measure R{sub g,0} of a surface as small as 1 m in diameter. The accuracy with which it can measure R{sub g,0} is otherwise comparable to that of the conventional pyranometer technique. A solar spectrophotometer can be used to determine R{sub g,0}{sup *}, a solar reflectance computed by averaging solar spectral reflectance weighted with AM1GH solar spectral irradiance. Neglecting instrument errors, R{sub g,0}{sup *} matches R{sub g,0} to within 0.006. The air mass 1.5 solar reflectance measured with version 5 of the Solar Spectrum Reflectometer can differ from R{sub g,0}{sup *} by as much as 0.08, but the AM1GH output of version 6 of this instrument matches R{sub g,0}{sup *} to within about 0.01. (author)

  19. Measuring solar reflectance Part II: Review of practical methods

    SciTech Connect

    Levinson, Ronnen; Akbari, Hashem; Berdahl, Paul

    2010-05-14

    A companion article explored how solar reflectance varies with surface orientation and solar position, and found that clear sky air mass 1 global horizontal (AM1GH) solar reflectance is a preferred quantity for estimating solar heat gain. In this study we show that AM1GH solar reflectance R{sub g,0} can be accurately measured with a pyranometer, a solar spectrophotometer, or an updated edition of the Solar Spectrum Reflectometer (version 6). Of primary concern are errors that result from variations in the spectral and angular distributions of incident sunlight. Neglecting shadow, background and instrument errors, the conventional pyranometer technique can measure R{sub g,0} to within 0.01 for surface slopes up to 5:12 [23{sup o}], and to within 0.02 for surface slopes up to 12:12 [45{sup o}]. An alternative pyranometer method minimizes shadow errors and can be used to measure R{sub g,0} of a surface as small as 1 m in diameter. The accuracy with which it can measure R{sub g,0} is otherwise comparable to that of the conventional pyranometer technique. A solar spectrophotometer can be used to determine R*{sub g,0}, a solar reflectance computed by averaging solar spectral reflectance weighted with AM1GH solar spectral irradiance. Neglecting instrument errors, R*{sub g,0} matches R{sub g,0} to within 0.006. The air mass 1.5 solar reflectance measured with version 5 of the Solar Spectrum Reflectometer can differ from R*{sub g,0} by as much as 0.08, but the AM1GH output of version 6 of this instrument matches R*{sub g,0} to within about 0.01.

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

    NASA Technical Reports Server (NTRS)

    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.