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  1. Analysis of repeated measures data

    CERN Document Server

    Islam, M Ataharul

    2017-01-01

    This book presents a broad range of statistical techniques to address emerging needs in the field of repeated measures. It also provides a comprehensive overview of extensions of generalized linear models for the bivariate exponential family of distributions, which represent a new development in analysing repeated measures data. The demand for statistical models for correlated outcomes has grown rapidly recently, mainly due to presence of two types of underlying associations: associations between outcomes, and associations between explanatory variables and outcomes. The book systematically addresses key problems arising in the modelling of repeated measures data, bearing in mind those factors that play a major role in estimating the underlying relationships between covariates and outcome variables for correlated outcome data. In addition, it presents new approaches to addressing current challenges in the field of repeated measures and models based on conditional and joint probabilities. Markov models of first...

  2. Measurement-based quantum repeaters

    CERN Document Server

    Zwerger, M; Briegel, H J

    2012-01-01

    We introduce measurement-based quantum repeaters, where small-scale measurement-based quantum processors are used to perform entanglement purification and entanglement swapping in a long-range quantum communication protocol. In the scheme, pre-prepared entangled states stored at intermediate repeater stations are coupled with incoming photons by simple Bell-measurements, without the need of performing additional quantum gates or measurements. We show how to construct the required resource states, and how to minimize their size. We analyze the performance of the scheme under noise and imperfections, with focus on small-scale implementations involving entangled states of few qubits. We find measurement-based purification protocols with significantly improved noise thresholds. Furthermore we show that already resource states of small size suffice to significantly increase the maximal communication distance. We also discuss possible advantages of our scheme for different set-ups.

  3. Multivariate linear models and repeated measurements revisited

    DEFF Research Database (Denmark)

    Dalgaard, Peter

    2009-01-01

    Methods for generalized analysis of variance based on multivariate normal theory have been known for many years. In a repeated measurements context, it is most often of interest to consider transformed responses, typically within-subject contrasts or averages. Efficiency considerations leads...

  4. On balanced minimal repeated measurements designs

    Directory of Open Access Journals (Sweden)

    Shakeel Ahmad Mir

    2014-10-01

    Full Text Available Repeated Measurements designs are concerned with scientific experiments in which each experimental unit is assigned more than once to a treatment either different or identical. This class of designs has the property that the unbiased estimators for elementary contrasts among direct and residual effects are obtainable. Afsarinejad (1983 provided a method of constructing balanced Minimal Repeated Measurements designs p < t , when t is an odd or prime power, one or more than one treatment may occur more than once in some sequences and  designs so constructed no longer remain uniform in periods. In this paper an attempt has been made to provide a new method to overcome this drawback. Specifically, two cases have been considered                RM[t,n=t(t-t/(p-1,p], λ2=1 for balanced minimal repeated measurements designs and  RM[t,n=2t(t-t/(p-1,p], λ2=2 for balanced  repeated measurements designs. In addition , a method has been provided for constructing              extra-balanced minimal designs for special case RM[t,n=t2/(p-1,p], λ2=1.

  5. Nonparametric additive regression for repeatedly measured data

    KAUST Repository

    Carroll, R. J.

    2009-05-20

    We develop an easily computed smooth backfitting algorithm for additive model fitting in repeated measures problems. Our methodology easily copes with various settings, such as when some covariates are the same over repeated response measurements. We allow for a working covariance matrix for the regression errors, showing that our method is most efficient when the correct covariance matrix is used. The component functions achieve the known asymptotic variance lower bound for the scalar argument case. Smooth backfitting also leads directly to design-independent biases in the local linear case. Simulations show our estimator has smaller variance than the usual kernel estimator. This is also illustrated by an example from nutritional epidemiology. © 2009 Biometrika Trust.

  6. Bayesian model selection of informative hypotheses for repeated measurements

    NARCIS (Netherlands)

    Mulder, Joris; Klugkist, I.G.; Schoot, Rens van de; Meeus, W.H.J.; Selfhout, Maarten; Hoijtink, Herbert

    2010-01-01

    When analyzing repeated measurements data, researchers often have expectations about the relations between the measurement means. The expectations can often be formalized using equality and inequality constraints between (i) the measurement means over time, (ii) the measurement means between

  7. Bayesian model selection of informative hypotheses for repeated measurements

    NARCIS (Netherlands)

    Mulder, J.|info:eu-repo/dai/nl/304823031; Klugkist, I.G.|info:eu-repo/dai/nl/27330089X; Van de Schoot, R.|info:eu-repo/dai/nl/304833207; Meeus, W.H.J.|info:eu-repo/dai/nl/070442215; van Zalk, M.H.W.|info:eu-repo/dai/nl/304836214; Hoijtink, H.J.A.|info:eu-repo/dai/nl/075184427

    2009-01-01

    When analyzing repeated measurements data, researchers often have expectations about the relations between the measurement means. The expectations can often be formalized using equality and inequality constraints between (i) the measurement means over time, (ii) the measurement means between groups,

  8. Analysis of repeated outcome measures from longitudinal studies

    Institute of Scientific and Technical Information of China (English)

    Yuanjia WANG; Naihua DUAN

    2011-01-01

    @@ In many clinical studies repeated measurements of an outcome are collected over time.For example,in an 8-week study of treatment for obsessive compulsive disorder,the severity of the disorder may be measured weekly using the Yale-Brown-Obsessive-Compulsive-Disorder-Scale (YBOCS).For each study participant who completes the study,there will be nine repeated measures of YBOCS (a baseline assessment plus eight assessments during the course of treatment).Such a study in which participants are followed and measured repeatedly over time is called a longitudinal study and the resulting data are called longitudinal data.

  9. Airborne Repeat Pass Interferometry for Deformation Measurements

    NARCIS (Netherlands)

    Groot, J.; Otten, M.; Halsema, E. van

    2000-01-01

    In ground engineering the need for deformation measurements is urgent. SAR interferometry can be used to measure small (sub-wavelength) deformations. An experiment to investigate this for dike deformations was set up, using the C-band SAR system PHARUS (PHased ARray Universal SAR). This paper descri

  10. Discriminant analysis for repeated measures data: a review

    Directory of Open Access Journals (Sweden)

    Lisa Lix

    2010-09-01

    Full Text Available Discriminant analysis (DA encompasses procedures for classifying observations into groups (i.e., predictive discriminative analysis and describing the relative importance of variables for distinguishing amongst groups (i.e., descriptive discriminative analysis. In recent years, a number of developments have occurred in DA procedures for the analysis of data from repeated measures designs. Specifically, DA procedures have been developed for repeated measures data characterized by missing observations and/or unbalanced measurement occasions, as well as high-dimensional data in which measurements are collected repeatedly on two or more variables. This paper reviews the literature on DA procedures for univariate and multivariate repeated measures data, focusing on covariance pattern and linear mixed-effects models. A numeric example illustrates their implementation using SAS software.

  11. Stability of parameters in repeated TVA measures

    DEFF Research Database (Denmark)

    Sørensen, Thomas Alrik

    Several recent studies have explored the limitations of human visual short-term memory or VSTM (e.g. Luck & Vogel, 1997; Wheeler & Treisman, 2002; Alvarez & Cavanagh, 2004). Usually researchers agree that VSTM is limited to a capacity of about 3 to 4 objects at any given moment (Cowan, 2001......). Capacity of short-term memory is measured in a range of studies often using the change detection paradigm (CD). However, the whole report paradigm (WR) may be a more reliable paradigm (Cusack, Lehmann, Veldsman, & Mitchell, 2009). Moreover, each individual WR trial yield more information compared to a CD...

  12. Correct use of repeated measures analysis of variance.

    Science.gov (United States)

    Park, Eunsik; Cho, Meehye; Ki, Chang-Seok

    2009-02-01

    In biomedical research, researchers frequently use statistical procedures such as the t-test, standard analysis of variance (ANOVA), or the repeated measures ANOVA to compare means between the groups of interest. There are frequently some misuses in applying these procedures since the conditions of the experiments or statistical assumptions necessary to apply these procedures are not fully taken into consideration. In this paper, we demonstrate the correct use of repeated measures ANOVA to prevent or minimize ethical or scientific problems due to its misuse. We also describe the appropriate use of multiple comparison tests for follow-up analysis in repeated measures ANOVA. Finally, we demonstrate the use of repeated measures ANOVA by using real data and the statistical software package SPSS (SPSS Inc., USA).

  13. Repeated measurement sampling in genetic association analysis with genotyping errors.

    Science.gov (United States)

    Lai, Renzhen; Zhang, Hong; Yang, Yaning

    2007-02-01

    Genotype misclassification occurs frequently in human genetic association studies. When cases and controls are subject to the same misclassification model, Pearson's chi-square test has the correct type I error but may lose power. Most current methods adjusting for genotyping errors assume that the misclassification model is known a priori or can be assessed by a gold standard instrument. But in practical applications, the misclassification probabilities may not be completely known or the gold standard method can be too costly to be available. The repeated measurement design provides an alternative approach for identifying misclassification probabilities. With this design, a proportion of the subjects are measured repeatedly (five or more repeats) for the genotypes when the error model is completely unknown. We investigate the applications of the repeated measurement method in genetic association analysis. Cost-effectiveness study shows that if the phenotyping-to-genotyping cost ratio or the misclassification rates are relatively large, the repeat sampling can gain power over the regular case-control design. We also show that the power gain is not sensitive to the genetic model, genetic relative risk and the population high-risk allele frequency, all of which are typically important ingredients in association studies. An important implication of this result is that whatever the genetic factors are, the repeated measurement method can be applied if the genotyping errors must be accounted for or the phenotyping cost is high.

  14. Influence of body position, food and beverage consumption on BIS measurements

    Science.gov (United States)

    Medrano, G.; Eitner, F.; Ismail, A. H.; Pikkemaat, R.; Cordes, A.; Floege, J.; Leonhardt, S.

    2010-04-01

    Continuous monitoring of fluid changes using bioimpedance spectroscopy (BIS) during hemodialysis could help to predict hypotensive complications and extend the patient's life. Food and beverage consumption during the treatment may influence the measurements and the calculated fluid removal. In the present article the change observed in whole body and segmental (knee-to-knee, abdomen) BIS measurements following a sequence similar to the one of dialysis treatment (lying down, sitting and eating, lying down) on healthy subjects is presented. The measurements have been performed using a commercial bioimpedance device with a frequency range of 5 kHz to 1 MHz. Knee-to-knee measurements seem to be less sensitive to these influences, compared to the standard whole body and the alternative abdomen BIS measurements. The results indicate that the individual influence of both body posture and food and beverage consumption may be superposed when combined.

  15. Assessing agreement with repeated measures for random observers.

    Science.gov (United States)

    Chen, Chia-Cheng; Barnhart, Huiman X

    2011-12-30

    Agreement studies are often concerned with assessing whether different observers for measuring responses on the same subject or sample can produce similar results. The concordance correlation coefficient (CCC) is a popular index for assessing the closeness among observers for quantitative measurements. Usually, the CCC is used for data without and with replications based on subject and observer effects only. However, we cannot use this methodology if repeated measurements rather than replications are collected. Although there exist some CCC-type indices for assessing agreement with repeated measurements, there is no CCC for random observers and random time points. In this paper, we propose a new CCC for repeated measures where both observers and time points are treated as random effects. A simulation study demonstrates our proposed methodology, and we use vertebral body data and image data for illustrations.

  16. Conservative Sample Size Determination for Repeated Measures Analysis of Covariance.

    Science.gov (United States)

    Morgan, Timothy M; Case, L Douglas

    2013-07-05

    In the design of a randomized clinical trial with one pre and multiple post randomized assessments of the outcome variable, one needs to account for the repeated measures in determining the appropriate sample size. Unfortunately, one seldom has a good estimate of the variance of the outcome measure, let alone the correlations among the measurements over time. We show how sample sizes can be calculated by making conservative assumptions regarding the correlations for a variety of covariance structures. The most conservative choice for the correlation depends on the covariance structure and the number of repeated measures. In the absence of good estimates of the correlations, the sample size is often based on a two-sample t-test, making the 'ultra' conservative and unrealistic assumption that there are zero correlations between the baseline and follow-up measures while at the same time assuming there are perfect correlations between the follow-up measures. Compared to the case of taking a single measurement, substantial savings in sample size can be realized by accounting for the repeated measures, even with very conservative assumptions regarding the parameters of the assumed correlation matrix. Assuming compound symmetry, the sample size from the two-sample t-test calculation can be reduced at least 44%, 56%, and 61% for repeated measures analysis of covariance by taking 2, 3, and 4 follow-up measures, respectively. The results offer a rational basis for determining a fairly conservative, yet efficient, sample size for clinical trials with repeated measures and a baseline value.

  17. Measurement and repeatability of interrupter resistance in unsedated newborn infants.

    Science.gov (United States)

    Adams, A M; Olden, C; Wertheim, D; Ives, A; Bridge, P D; Lenton, J; Seddon, P

    2009-12-01

    Interrupter resistance (R(int)) is a useful measure of airway caliber in young children, but has not been well characterized in infants-in whom there are concerns about the accurate measurement of driving pressure. This study aimed to assess the feasibility and repeatability of measuring R(int) in unsedated newborn infants, and to explore alternative algorithms for calculating driving pressure. R(int) measurement was attempted in 28 healthy term newborn infants during natural sleep using the MicroRint device. Paired R(int) measurements were achieved in 24 infants, but after screening of waveforms only 15 infants had at least 5 technically acceptable waveforms on both measurements. R(int) values obtained were comparable with reported values for airflow resistance in newborns using other methods. However, the repeatability coefficient (CR) was much higher than reported values in preschool children using standard back-extrapolation algorithms, with CR 2.47 KPa L(-1) sec (unscreened) and 2.93 KPa L(-1) sec (screened). Other algorithms gave only marginally better repeatability, with all CR values over 50% of the mean R(int) value. Using current commercially available equipment, R(int) is too poorly repeatable to be a reliable measurement of airflow resistance in newborn infants. Lower deadspace equipment is needed, but anatomical and physiological factors in the infant are also important.

  18. Modeling repeated measurement data for occupational exposure assessment and epidemiology

    NARCIS (Netherlands)

    Peretz, Chava

    2004-01-01

    Repeated measurements designs, occur frequently in the assessment of exposure to toxic chemicals. This thesis deals with the possibilities of using mixed effects models for occupational exposure assessment and in the analysis of exposure response relationships. The model enables simultaneous estima

  19. Applying the General Linear Model to Repeated Measures Problems.

    Science.gov (United States)

    Pohlmann, John T.; McShane, Michael G.

    The purpose of this paper is to demonstrate the use of the general linear model (GLM) in problems with repeated measures on a dependent variable. Such problems include pretest-posttest designs, multitrial designs, and groups by trials designs. For each of these designs, a GLM analysis is demonstrated wherein full models are formed and restrictions…

  20. Positional Repeatability Measurements Of Stepper Motors At Cryogenic Temperatures

    Science.gov (United States)

    Pompea, Stephen M.; Hall, Michael S.; Bartko, Frank; Houck, James R.

    1983-08-01

    Stepper motors operating at liquid helium temperature have multiple applications in cryogenically-cooled telescopes such as the Shuttle Infrared Telescope Facility (SIRTF). These SIRTF applications include driving cryogen flow valves, operating the Multiple Instrument Chamber (MIC) beam splitter mechanism, and operating filters and grating wheel mechanisms in the scientific instruments. The positional repeatability of the beam splitter drive mechanism is especially critical since it feeds the optical beam to the scien-tific instruments. Despite these important applications, no significant data on the positional repeatability of stepper motors at cryogenic temperatures has been available. Therefore, we conducted a series of measurements to determine the positional repeatability of a modified, off-the-shelf Berger/Lahr stepper motor (model RDM 253/25, step angle 3.6°) which had demonstrated excellent performance in previous endurance testing at LHe temperature. These test results indicated that the positional repeatability of the motor was excellent at all temperatures, with somewhat better performance at cryogenic temperatures. Another important result was that the motor could be repeatedly turned off and on while still accurately retaining its rotor position.

  1. Lecture notes on: Electrical theory behind the measurement of body fluids with bioimpedance spectroscopy (BIS)

    DEFF Research Database (Denmark)

    Jødal, Lars

    The lecture notes describe how body fluid volumes can be measured/estimated using the technique bio-impedance spectroscopy (BIS). The opening chapters assume little or none technical/mathematical knowledge and can hopefully be read by anyone interested in the techneque. Later chapters become more...

  2. Lecture notes on: Electrical theory behind the measurement of body fluids with bioimpedance spectroscopy (BIS)

    DEFF Research Database (Denmark)

    Jødal, Lars

    The lecture notes describe how body fluid volumes can be measured/estimated using the technique bio-impedance spectroscopy (BIS). The opening chapters assume little or none technical/mathematical knowledge and can hopefully be read by anyone interested in the techneque. Later chapters become more...

  3. Repeatability of OCT lens thickness measures with age and accommodation.

    Science.gov (United States)

    Doyle, Lesley; Little, Julie-Anne; Saunders, Kathryn J

    2013-12-01

    To investigate crystalline lens thickness (LT) across a range of ages and accommodative demands and to evaluate the repeatability of LT measurements using the Visante Anterior Segment Optical Coherence Tomographer (AS-OCT) (Zeiss Meditec, Germany) under non-cycloplegic conditions. Participants were 98 visually normal adults aged 18-75 years, stratified into age groups of 18-29, 30-39, 40-49, 50-59, and 60-75 years of age. Images of the crystalline lens were taken using the Visante AS-OCT during stimulation of accommodation at demands of 0, 1, 2, 3, 4, 5, and 8 D with accommodative response measured in a subgroup of participants. Images were analyzed and LT measured assuming a refractive index of 1.42. Repeat measures were taken from 86 participants for each accommodative demand at a second visit. The mean unaccommodated LT for all participants was 4.07 ± 0.40 mm. An average increase in LT of 20 μm per year was calculated (linear regression, R² = 0.61, F(1,89) = 143.92, p report the repeatability of LT measures using the Visante AS-OCT in the non-cyclopleged eye. It has also demonstrated the ability of the Visante AS-OCT to detect small changes in lens thickness with accommodation.

  4. Measuring Repeatability of the Focus-variable Lenses

    Directory of Open Access Journals (Sweden)

    Jan Řezníček

    2014-12-01

    Full Text Available In the field of photogrammetry, the optical system, usually represented by the glass lens, is used for metric purposes. Therefore, the aberration characteristics of such a lens, inducing deviations from projective imaging, has to be well known. However, the most important property of the metric lens is the stability of its glass and mechanical elements, ensuring long-term reliability of the measured parameters. In case of a focus-variable lens, the repeatability of the lens setup is important as well. Lenses with a fixed focal length are usually considered as “fixed” though, in fact, most of them contain one or more movable glass elements, providing the focusing function. In cases where the lens is not equipped with fixing screws, the repeatability of the calibration parameters should be known. This paper derives simple mathematical formulas that can be used for measuring the repeatability of the focus-variable lenses, and gives a demonstrative example of such measuring. The given procedure has the advantage that only demanded parameters are estimated, hence, no unwanted correlations with the additional parameters exist. The test arrangement enables us to measure each demanded magnification of the optical system, which is important in close-range photogrammetry.

  5. Capturing learning effects on eye movements in repeated measures experiments

    DEFF Research Database (Denmark)

    Bagger, Martin; Orquin, Jacob Lund; Fiedler, Susann

    We propose and illustrate that repeated exposure to stimuli sets increases the size of the saccade amplitudes. Saccadic amplitudes are closely related to the perceptual span and therefore used as a measure for the information intake in an experiment. Studies on expertise have shown that experts...... experiment in which 68 participants made choices between four alternatives with three different between subject conditions varying in presentation format (verbal matrix, a pictorial matrix, and a realistic product representation). The results consistently demonstrate an increase of the saccade amplitude over...... the course of the experiment independent of condition. We conclude by discussing our results in the light of the possible increase of the perceptual span and its implications for the research procedure in eye-tracking experiments with a repeated measurement design....

  6. Modeling intraindividual variability with repeated measures data methods and applications

    CERN Document Server

    Hershberger, Scott L

    2013-01-01

    This book examines how individuals behave across time and to what degree that behavior changes, fluctuates, or remains stable.It features the most current methods on modeling repeated measures data as reported by a distinguished group of experts in the field. The goal is to make the latest techniques used to assess intraindividual variability accessible to a wide range of researchers. Each chapter is written in a ""user-friendly"" style such that even the ""novice"" data analyst can easily apply the techniques.Each chapter features:a minimum discussion of mathematical detail;an empirical examp

  7. Unitarity, Feedback, Interactions -- Dynamics Emergent from Repeated Measurements

    CERN Document Server

    Altamirano, Natacha; Mann, Robert B; Zych, Magdalena

    2016-01-01

    Motivated by the recent efforts to describe the gravitational interaction as a classical channel arising from continuous quantum measurements, we study what types of dynamics can emerge from a model of repeated short interactions of a system with a set of ancillae. We show that contingent on the model parameters the resulting dynamics ranges from exact unitarity to arbitrary fast decoherence (quantum Zeno effect). For a series of measurements the effective dynamics includes feedback-control, which for a composite system yields effective interactions between the subsystems. We quantify the amount of decoherence accompanying such induced interactions, generalizing the lower bound of the gravitational example. However, by allowing multipartite measurements, the interactions can be induced with arbitrary low decoherence. Our results have implications for gravity-inspired decoherence models and the simple framework used in the present study can find applications in devising novel quantum control protocols, or quan...

  8. Repeated High-Precision Gravity and GPS Measurement Techniques

    Science.gov (United States)

    Gettings, P.; Harris, R. N.; Allis, R.; Chapman, D. S.

    2003-12-01

    Repeated high-precision gravity and GPS measurements are becoming a common tool for tracking changes in subsurface reservoirs. Despite this, there is little literature which discusses measurement techniques and the expected errors. Our research has focused on improving measurement techniques to be applied to ground water and geothermal steam reservoirs, including quantifying the minimum error levels with modern equipment. We applied these methods in two studies: ground water monitoring of the southern Salt Lake valley, Utah, USA, and steam monitoring of The Geysers geothermal field, California, USA. Gravity measurements using modern relative high-precision meters, such as Scintrex CG-3Ms or L&R E series, can now be routinely made to an accuracy of 5 μ Gal. Such accuracy requires the use of time series analysis at each station, and non-linear instrument drift functions. Modern computerized meters are capable of internally storing a time series of measurements for each station; older meters can often be fitted to log such data to a field computer. This time series, typically of 10-15 minute duration in our work, can then be analyzed in several ways to produce stable estimates of the gravity reading. In particular, our research has emphasized using a weighted arithmetic average (for long occupations), or a Thiele extrapolation scheme (for shorter station occupations). Instrument drift is removed through a superposition of a linear long-term drift function, and an empirical staircase function formed from differences between repeated station occupations. To achieve high-accuracy GPS measurements while maximizing the number of field stations in a survey, rapid-static measurements are necessary. We have tested the effect of occupation time and processing schemes on the absolute accuracy of the resulting GPS position. Using a post-processing differential method with a fixed (but not necessarily continuous) base station within 15 km, positioning error of <4 cm vertical is

  9. Quasar Variability Measurements With SDSS Repeated Imaging and POSS Data

    CERN Document Server

    Ivezic, Z; Juric, M; Anderson, S; Hall, P B; Richards, G T; Rockosi, C M; Vanden Berk, Daniel E; Turner, E L; Knapp, G R; Gunn, J E; Schlegel, D J; Strauss, M A; Schneider, D P

    2004-01-01

    We analyze the properties of quasar variability using repeated SDSS imaging data in five UV-to-far red photometric bands, accurate to 0.02 mag, for 13,000 spectroscopically confirmed quasars. The observed time lags span the range from 3 hours to over 3 years, and constrain the quasar variability for rest-frame time lags of up to two years, and at rest-frame wavelengths from 1000 Ang. to 6000 Ang. We demonstrate that 66,000 SDSS measurements of magnitude differences can be described within the measurement noise by a simple function of only three free parameters. The addition of POSS data constrains the long-term behavior of quasar variability and provides evidence for a turn-over in the structure function. This turn-over indicates that the characteristic time scale for optical variability of quasars is of the order 1 year.

  10. Dispersion Measure Variation of Repeating Fast Radio Burst Sources

    Science.gov (United States)

    Yang, Yuan-Pei; Zhang, Bing

    2017-09-01

    The repeating fast radio burst (FRB) 121102 was recently localized in a dwarf galaxy at a cosmological distance. The dispersion measure (DM) derived for each burst from FRB 121102 so far has not shown significant evolution, even though an apparent increase was recently seen with newly detected VLA bursts. It is expected that more repeating FRB sources may be detected in the future. In this work, we investigate a list of possible astrophysical processes that might cause DM variation of a particular FRB source. The processes include (1) cosmological scale effects such as Hubble expansion and large-scale structure fluctuations; (2) FRB local effects such as gas density fluctuation, expansion of a supernova remnant (SNR), a pulsar wind nebula, and an H ii region; and (3) the propagation effect due to plasma lensing. We find that the DM variations contributed by the large-scale structure are extremely small, and any observable DM variation is likely caused by the plasma local to the FRB source. In addition to mechanisms that decrease DM over time, we suggest that an FRB source in an expanding SNR around a nearly neutral ambient medium during the deceleration (Sedov–Taylor and snowplow) phases or in a growing H ii region can increase DM. Some effects (e.g., an FRB source moving in an H ii region or plasma lensing) can produce either positive or negative DM variations. Future observations of DM variations of FRB 121102 and other repeating FRB sources can provide important clues regarding the physical origin of these sources.

  11. Coseismic and postseismic velocity changes measured by repeating earthquakes

    Science.gov (United States)

    Schaff, David P.; Beroza, Gregory C.

    2004-10-01

    Repeating earthquakes that rupture approximately the same fault patch and have nearly identical waveforms are a useful tool for measuring temporal changes in wave propagation in the Earth's crust. Since source and path effects are common to all earthquakes in a repeating earthquake sequence (multiplet), differences in their waveforms can be attributed to changes in the characteristics of the medium. We have identified over 20 multiplets containing between 5 and 40 repeating events in the aftershock zones of the 1989 Loma Prieta and 1984 Morgan Hill, California, earthquakes. Postmain shock events reveal delays of phases in the early S wave coda of as much as 0.2 s relative to premain shock events. The delay amounts to a path-averaged coseismic velocity decrease of about 1.5% for P waves and 3.5% for S waves. Since most of the multiplets are aftershocks and follow Omori's law, we have excellent temporal sampling in the immediate postmain shock period. We find that the amplitude of the velocity decrease decays logarithmically in time following the main shock. In some cases it returns to the premain shock values, while in others it does not. Similar results are obtained for the Morgan Hill main shock. Because the fractional change in S wave velocity is greater than the fractional change in P wave velocity, it suggests that the opening or connection of fluid-filled fractures is the underlying cause. The magnitude of the velocity change implies that low effective pressures are present in the source region of the velocity change. Our results suggest that the changes are predominantly near the stations and shallow, but we cannot exclude the possibility that changes occur at greater depth as well. If the variations are shallow, we may be detecting the lingering effects of nonlinearity during main shock strong ground motion. If the variations are deep, it suggests that pore pressures at seismogenic depths are high, which would likely play a key role in the earthquake process.

  12. Intracellular distribution of fluorescent copper and zinc bis(thiosemicarbazonato) complexes measured with fluorescence lifetime spectroscopy.

    Science.gov (United States)

    Hickey, James L; James, Janine L; Henderson, Clare A; Price, Katherine A; Mot, Alexandra I; Buncic, Gojko; Crouch, Peter J; White, Jonathan M; White, Anthony R; Smith, Trevor A; Donnelly, Paul S

    2015-10-05

    The intracellular distribution of fluorescently labeled copper and zinc bis(thiosemicarbazonato) complexes was investigated in M17 neuroblastoma cells and primary cortical neurons with a view to providing insights into the neuroprotective activity of a copper bis(thiosemicarbazonato) complex known as Cu(II)(atsm). Time-resolved fluorescence measurements allowed the identification of the Cu(II) and Zn(II) complexes as well as the free ligand inside the cells by virtue of the distinct fluorescence lifetime of each species. Confocal fluorescent microscopy of cells treated with the fluorescent copper(II)bis(thiosemicarbazonato) complex revealed significant fluorescence associated with cytoplasmic puncta that were identified to be lysosomes in primary cortical neurons and both lipid droplets and lysosomes in M17 neuroblastoma cells. Fluorescence lifetime imaging microscopy confirmed that the fluorescence signal emanating from the lipid droplets could be attributed to the copper(II) complex but also that some degree of loss of the metal ion led to diffuse cytosolic fluorescence that could be attributed to the metal-free ligand. The accumulation of the copper(II) complex in lipid droplets could be relevant to the neuroprotective activity of Cu(II)(atsm) in models of amyotrophic lateral sclerosis and Parkinson's disease.

  13. Bayesian Concordance Correlation Coefficient with Application to Repeatedly Measured Data

    Directory of Open Access Journals (Sweden)

    Atanu BHATTACHARJEE

    2015-10-01

    Full Text Available Objective: In medical research, Lin's classical concordance correlation coefficient (CCC is frequently applied to evaluate the similarity of the measurements produced by different raters or methods on the same subjects. It is particularly useful for continuous data. The objective of this paper is to propose the Bayesian counterpart to compute CCC for continuous data. Material and Methods: A total of 33 patients of astrocytoma brain treated in the Department of Radiation Oncology at Malabar Cancer Centre is enrolled in this work. It is a continuous data of tumor volume and tumor size repeatedly measured during baseline pretreatment workup and post surgery follow-ups for all patients. The tumor volume and tumor size are measured separately by MRI and CT scan. The agreement of measurement between MRI and CT scan is calculated through CCC. The statistical inference is performed through Markov Chain Monte Carlo (MCMC technique. Results: Bayesian CCC is found suitable to get prominent evidence for test statistics to explore the relation between concordance measurements. The posterior mean estimates and 95% credible interval of CCC on tumor size and tumor volume are observed with 0.96(0.87,0.99 and 0.98(0.95,0.99 respectively. Conclusion: The Bayesian inference is adopted for development of the computational algorithm. The approach illustrated in this work provides the researchers an opportunity to find out the most appropriate model for specific data and apply CCC to fulfill the desired hypothesis.

  14. A Simple and Transparent Alternative to Repeated Measures ANOVA

    Directory of Open Access Journals (Sweden)

    James W. Grice

    2015-09-01

    Full Text Available Observation Oriented Modeling is a novel approach toward conceptualizing and analyzing data. Compared with traditional parametric statistics, Observation Oriented Modeling is more intuitive, relatively free of assumptions, and encourages researchers to stay close to their data. Rather than estimating abstract population parameters, the overarching goal of the analysis is to identify and explain distinct patterns within the observations. Selected data from a recent study by Craig et al. were analyzed using Observation Oriented Modeling; this analysis was contrasted with a traditional repeated measures ANOVA assessment. Various pitfalls in traditional parametric analyses were avoided when using Observation Oriented Modeling, including the presence of outliers and missing data. The differences between Observation Oriented Modeling and various parametric and nonparametric statistical methods were finally discussed.

  15. Matrix-based concordance correlation coefficient for repeated measures.

    Science.gov (United States)

    Hiriote, Sasiprapa; Chinchilli, Vernon M

    2011-09-01

    In many clinical studies, Lin's concordance correlation coefficient (CCC) is a common tool to assess the agreement of a continuous response measured by two raters or methods. However, the need for measures of agreement may arise for more complex situations, such as when the responses are measured on more than one occasion by each rater or method. In this work, we propose a new CCC in the presence of repeated measurements, called the matrix-based concordance correlation coefficient (MCCC) based on a matrix norm that possesses the properties needed to characterize the level of agreement between two p× 1 vectors of random variables. It can be shown that the MCCC reduces to Lin's CCC when p= 1. For inference, we propose an estimator for the MCCC based on U-statistics. Furthermore, we derive the asymptotic distribution of the estimator of the MCCC, which is proven to be normal. The simulation studies confirm that overall in terms of accuracy, precision, and coverage probability, the estimator of the MCCC works very well in general cases especially when n is greater than 40. Finally, we use real data from an Asthma Clinical Research Network (ACRN) study and the Penn State Young Women's Health Study for demonstration.

  16. [Analysis of binary classification repeated measurement data with GEE and GLMMs using SPSS software].

    Science.gov (United States)

    An, Shengli; Zhang, Yanhong; Chen, Zheng

    2012-12-01

    To analyze binary classification repeated measurement data with generalized estimating equations (GEE) and generalized linear mixed models (GLMMs) using SPSS19.0. GEE and GLMMs models were tested using binary classification repeated measurement data sample using SPSS19.0. Compared with SAS, SPSS19.0 allowed convenient analysis of categorical repeated measurement data using GEE and GLMMs.

  17. Rank-Based Analysis of Unbalanced Repeated Measures Data

    Directory of Open Access Journals (Sweden)

    M. Mushfiqur Rashid

    2012-07-01

    Full Text Available Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman","serif";} In this article, we have developed a rank (intra-subject based analysis of clinical trials with unbalanced repeated measures data. We assume that the errors within each patient are exchangeable and continuous random variables. This rank-based inference is valid when the unbalanced data are missing either completely at random or by design. A drop in dispersion test is developed for general linear hypotheses. A numerical example is given to illustrate the procedure.

  18. Repeated swim stress alters brain benzodiazepine receptors measured in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Weizman, R.; Weizman, A.; Kook, K.A.; Vocci, F.; Deutsch, S.I.; Paul, S.M.

    1989-06-01

    The effects of repeated swim stress on brain benzodiazepine receptors were examined in the mouse using both an in vivo and in vitro binding method. Specific in vivo binding of (/sup 3/H)Ro15-1788 to benzodiazepine receptors was decreased in the hippocampus, cerebral cortex, hypothalamus, midbrain and striatum after repeated swim stress (7 consecutive days of daily swim stress) when compared to nonstressed mice. In vivo benzodiazepine receptor binding was unaltered after repeated swim stress in the cerebellum and pons medulla. The stress-induced reduction in in vivo benzodiazepine receptor binding did not appear to be due to altered cerebral blood flow or to an alteration in benzodiazepine metabolism or biodistribution because there was no difference in (14C)iodoantipyrine distribution or whole brain concentrations of clonazepam after repeated swim stress. Saturation binding experiments revealed a change in both apparent maximal binding capacity and affinity after repeated swim stress. Moreover, a reduction in clonazepam's anticonvulsant potency was also observed after repeated swim stress (an increase in the ED50 dose for protection against pentylenetetrazol-induced seizures), although there was no difference in pentylenetetrazol-induced seizure threshold between the two groups. In contrast to the results obtained in vivo, no change in benzodiazepine receptor binding kinetics was observed using the in vitro binding method. These data suggest that environmental stress can alter the binding parameters of the benzodiazepine receptor and that the in vivo and in vitro binding methods can yield substantially different results.

  19. [Analysis of variance of repeated data measured by water maze with SPSS].

    Science.gov (United States)

    Qiu, Hong; Jin, Guo-qin; Jin, Ru-feng; Zhao, Wei-kang

    2007-01-01

    To introduce the method of analyzing repeated data measured by water maze with SPSS 11.0, and offer a reference statistical method to clinical and basic medicine researchers who take the design of repeated measures. Using repeated measures and multivariate analysis of variance (ANOVA) process of the general linear model in SPSS and giving comparison among different groups and different measure time pairwise. Firstly, Mauchly's test of sphericity should be used to judge whether there were relations among the repeatedly measured data. If any (PSPSS statistical package is available to fulfil this process.

  20. Detecting tropical forest biomass dynamics from repeated airborne lidar measurements

    Directory of Open Access Journals (Sweden)

    V. Meyer

    2013-08-01

    census data, differences of approximately one year between the ground census and lidar measurements, and differences in sensor characteristics. Our results indicate that the 50 ha BCI plot lost a significant amount of biomass (−0.8 Mg ha−1 yr−1 ± 2.2(SD over the past decade (2000–2010. Over the entire island and during the same period, mean AGB change was 0.2 ± 2.4 Mg ha−1 yr−1 with old growth forests losing −0.7 Mg ha−1 yr−1 ± 2.2 (SD, and secondary forests gaining +1.8 Mg ha yr−1 ± 3.4 (SD biomass. Our analysis suggests that repeated lidar surveys, despite taking measurement with different sensors, can estimate biomass changes in old-growth tropical forests at landscape scales (>10 ha.

  1. Tandem repeats, high copy number and remarkable diel expression rhythm of form II RuBisCO in Prorocentrum donghaiense (Dinophyceae.

    Directory of Open Access Journals (Sweden)

    Xinguo Shi

    Full Text Available Gene structure and expression regulation of form II RuBisCO (rbcII in dinoflagellates are still poorly understood. Here we isolated this gene (Pdrbc and investigated its diel expression pattern in a harmful algal bloom forming dinoflagellate Prorocentrum donghaiense. We obtained cDNA sequences with triple tandem repeats of the coding unit (CU; the 5' region has the sequence of a typical dinoflagellate plastid gene, encoding an N-terminus with two transmembrane regions separated by a plastid transit peptide. The CUs (1,455 bp except 1464 bp in last CU are connected through a 63 bp spacer. Phylogenetic analysis showed that rbcII CUs within species formed monophyletic clusters, indicative of intraspecific gene duplication or purifying evolution. Using quantitative PCR (qPCR we estimated 117±40 CUs of Pdrbc in the P. donghaiense genome. Although it is commonly believed that most dinoflagellate genes lack transcriptional regulation, our RT-qPCR analysis on synchronized cultures revealed remarkable diel rhythm of Pdrbc expression, showing significant correlations of transcript abundance with the timing of the dark-to-light transition and cell cycle G2M-phase. When the cultures were shifted to continuous light, Pdrbc expression remained significantly correlated with the G2M-phase. Under continuous darkness the cell cycle was arrested at the G1 phase, and the rhythm of Pdrbc transcription disappeared. Our results suggest that dinoflagellate rbcII 1 undergoes duplication or sequence purification within species, 2 is organized in tandem arrays in most species probably to facilitate efficient translation and import of the encoded enzyme, and 3 is regulated transcriptionally in a cell cycle-dependent fashion at least in some dinoflagellates.

  2. Using repeated measures of sleep disturbances to predict future diagnosis-specific work disability

    DEFF Research Database (Denmark)

    Salo, Paula; Vahtera, Jussi; Hall, Martica

    2012-01-01

    It is unknown whether or not measuring sleep disturbances repeatedly, rather than at only one point in time, improves prediction of work disability.......It is unknown whether or not measuring sleep disturbances repeatedly, rather than at only one point in time, improves prediction of work disability....

  3. Intelligence Is in the Eye of the Beholder: Investigating Repeated IQ Measurements in Forensic Psychiatry

    Science.gov (United States)

    Habets, Petra; Jeandarme, Inge; Uzieblo, Kasia; Oei, Karel; Bogaerts, Stefan

    2015-01-01

    Background: A stable assessment of cognition is of paramount importance for forensic psychiatric patients (FPP). The purpose of this study was to compare repeated measures of IQ scores in FPPs with and without intellectual disability. Methods: Repeated measurements of IQ scores in FPPs (n = 176) were collected. Differences between tests were…

  4. Intelligence Is in the Eye of the Beholder: Investigating Repeated IQ Measurements in Forensic Psychiatry

    Science.gov (United States)

    Habets, Petra; Jeandarme, Inge; Uzieblo, Kasia; Oei, Karel; Bogaerts, Stefan

    2015-01-01

    Background: A stable assessment of cognition is of paramount importance for forensic psychiatric patients (FPP). The purpose of this study was to compare repeated measures of IQ scores in FPPs with and without intellectual disability. Methods: Repeated measurements of IQ scores in FPPs (n = 176) were collected. Differences between tests were…

  5. Assessment of bone loss with repeated bone mineral measurements: Application to measurements on the individual patient

    Energy Technology Data Exchange (ETDEWEB)

    Wahner, H.W.

    1987-02-01

    Longitudinal measurements on lumbar spine and mid-radius were made by bone absorptiometry techniques in 139 normal women. Bone mineral was measured every 6 months over an median interval of 2.1 years. The results revealed that bone loss at different skeletal sites is non-uniform with equal bone loss patterns in all patients and relatively small variations in bone loss rate between normal women. For achieving these results there is strong demand on high precision and properly spaced measuring intervals for long-term rate of loss measurements. For exclusion of progressive degenerative disease a radiographic evaluation of the spine in the beginning and at the end of the study is mandatory as compression fractures or trauma reveal bone mineral changes independent from the agerelated bone loss. These repeated bone mineral measurements are useful for monitoring and follow-up studies during different therapeutic regimens.

  6. Junction formation of Cu3BiS3 investigated by Kelvin probe force microscopy and surface photovoltage measurements

    Science.gov (United States)

    Mesa, Fredy; Chamorro, William; Vallejo, William; Baier, Robert; Dittrich, Thomas; Grimm, Alexander; Lux-Steiner, Martha C

    2012-01-01

    Summary Recently, the compound semiconductor Cu3BiS3 has been demonstrated to have a band gap of ~1.4 eV, well suited for photovoltaic energy harvesting. The preparation of polycrystalline thin films was successfully realized and now the junction formation to the n-type window needs to be developed. We present an investigation of the Cu3BiS3 absorber layer and the junction formation with CdS, ZnS and In2S3 buffer layers. Kelvin probe force microscopy shows the granular structure of the buffer layers with small grains of 20–100 nm, and a considerably smaller work-function distribution for In2S3 compared to that of CdS and ZnS. For In2S3 and CdS buffer layers the KPFM experiments indicate negatively charged Cu3BiS3 grain boundaries resulting from the deposition of the buffer layer. Macroscopic measurements of the surface photovoltage at variable excitation wavelength indicate the influence of defect states below the band gap on charge separation and a surface-defect passivation by the In2S3 buffer layer. Our findings indicate that Cu3BiS3 may become an interesting absorber material for thin-film solar cells; however, for photovoltaic application the band bending at the charge-selective contact has to be increased. PMID:22497001

  7. Junction formation of Cu3BiS3 investigated by Kelvin probe force microscopy and surface photovoltage measurements

    Directory of Open Access Journals (Sweden)

    Fredy Mesa

    2012-03-01

    Full Text Available Recently, the compound semiconductor Cu3BiS3 has been demonstrated to have a band gap of ~1.4 eV, well suited for photovoltaic energy harvesting. The preparation of polycrystalline thin films was successfully realized and now the junction formation to the n-type window needs to be developed. We present an investigation of the Cu3BiS3 absorber layer and the junction formation with CdS, ZnS and In2S3 buffer layers. Kelvin probe force microscopy shows the granular structure of the buffer layers with small grains of 20–100 nm, and a considerably smaller work-function distribution for In2S3 compared to that of CdS and ZnS. For In2S3 and CdS buffer layers the KPFM experiments indicate negatively charged Cu3BiS3 grain boundaries resulting from the deposition of the buffer layer. Macroscopic measurements of the surface photovoltage at variable excitation wavelength indicate the influence of defect states below the band gap on charge separation and a surface-defect passivation by the In2S3 buffer layer. Our findings indicate that Cu3BiS3 may become an interesting absorber material for thin-film solar cells; however, for photovoltaic application the band bending at the charge-selective contact has to be increased.

  8. Impulsivity components measured by the Brazilian version of the Barratt Impulsiveness Scale (BIS-11

    Directory of Open Access Journals (Sweden)

    Alina Gomide Vasconcelos

    2015-03-01

    Full Text Available The main purpose of this study was to investigate the psychometric properties of the Barratt Impulsiveness Scale (BIS-11. Content item analysis was conducted by seven doctoral students. A convenience sample of 897 students was submitted to BIS-11 and they also filled self-reports about Minor Mental Disorder and ADHD symptoms, alcohol use and cigarette smoking. Mean age was 27.32 (SD=8.69 years, 56% were female and 52% had incomplete college degree. Content and factorial analyses revealed that impulsivity was best represented by two latent factors labeled non-planning and inhibition behaviors. Test retest agreement tended to produce similar score patterns seven months after the first evaluation. Additionally, BIS-11 scores discriminated subjects in terms of cigarette smoking and psychopathological symptoms, which indicated evidences regarding criterion-related validity. The theoretical discussion was present based on the neuropsychological model of hot and cool aspects of executive function.

  9. Repeatability of gait pattern variables measured by use of extremity-mounted inertial measurement units in nonlame horses during trotting.

    Science.gov (United States)

    Cruz, Antonio M; Maninchedda, Ugo E; Burger, Dominik; Wanda, Sabine; Vidondo, Beatriz

    2017-09-01

    OBJECTIVE To determine repeatability of gait variables measured by use of extremity-mounted inertial measurement units (IMUs) in nonlame horses during trotting under controlled conditions of treadmill exercise. ANIMALS 10 horses. PROCEDURES Six IMUs were strapped to the metacarpal, metatarsal, and distal tibial regions of each horse. Data were collected in a standardized manner (3 measurements/d on 3 d/wk over a 3-week period) while each horse was trotted on a treadmill. Every measurement consisted of a minimum of 20 strides from which a minimum of 10 strides was selected for analysis. Spatial and temporal variables were derived from the IMUs. Repeatability coefficients based on the within-subject SD were computed for each gait analysis variable at each week. RESULTS Most of the temporal and spatial variables had high repeatability (repeatability coefficients variables, specifically the symmetry variables (which were calculated from other variables), had somewhat higher repeatability coefficients (ie, lower repeatability) only in the last week. CONCLUSIONS AND CLINICAL RELEVANCE With the exceptions of some symmetry variables, which may reflect individual variations during movement, the extremity-mounted IMUs provided data with high repeatability for nonlame horses trotting under controlled conditions of treadmill exercise. Repeatability was achieved for each instrumented limb segment with regard to the spatial relationship between 2 adjacent segments (joint angles) and the temporal relationship among all segments (limb phasing). Extremity-mounted IMUs could have the potential to become a method for gait analysis in horses.

  10. Analysis of repeated measurements from medical research when observations are missing

    OpenAIRE

    Walker, K.

    2007-01-01

    Subject dropout is a common problem in repeated measurements health stud ies. Where dropout is related to the response, the results obtained can be substantially biased. The research in this thesis is motivated by a repeated measurements asthma clinical trial with substantial patient dropout. In practice the extent to which missing observations affect parameter esti mates and their efficiency is not clear. Through extensive simulation studies under various scenarios and missing data mechanism...

  11. Repeatability of Ocular Measurements with a Dual-Scheimpflug Analyzer in Healthy Eyes

    Directory of Open Access Journals (Sweden)

    Carmen Lopez de la Fuente

    2014-01-01

    Full Text Available Purpose. To assess the repeatability of the Galilei dual Scheimpflug analyzer (GDSA in anterior segment examination. Methods. Fifty-two eyes from 52 healthy volunteers were prospectively and consecutively recruited. Anatomic, axial, refractive, and instantaneous parameters were measured with GDSA to provide a complete characterization of the anterior segment. Repeatability was assessed calculating intraclass correlation coefficient (ICC, and coefficient of variation (COV. Results. Correlation among repeated measurements showed almost perfect reliability (ICC > 0.81 for all parameters except thinnest central corneal thickness (CCT (0.78, corneal thickness average out (0.79, and posterior axial curvature average out (0.60. Repeatability was excellent (COV < 10% for all parameters except anterior chamber volume and, superior iridocorneal angle and eccentricities. In these last three parameters, repeatability limits were excessively high compared to the mean. Conclusions. GDSA in healthy young persons had an almost perfect correlation in measuring anatomic, axial, instantaneous, and refractive parameters with greater variability for peripheral terms. Repeatability of anatomical parameters like pachymetry, anterior chamber, or iridocorneal angle and eccentricity were limited. In healthy young persons, the other evaluated parameters had very good repeatability and their limits of agreement showed excellent clinical results for this device.

  12. A Novel Signal Processing Measure to Identify Exact and Inexact Tandem Repeat Patterns in DNA Sequences

    Directory of Open Access Journals (Sweden)

    Ravi Gupta

    2007-03-01

    Full Text Available The identification and analysis of repetitive patterns are active areas of biological and computational research. Tandem repeats in telomeres play a role in cancer and hypervariable trinucleotide tandem repeats are linked to over a dozen major neurodegenerative genetic disorders. In this paper, we present an algorithm to identify the exact and inexact repeat patterns in DNA sequences based on orthogonal exactly periodic subspace decomposition technique. Using the new measure our algorithm resolves the problems like whether the repeat pattern is of period P or its multiple (i.e., 2P, 3P, etc., and several other problems that were present in previous signal-processing-based algorithms. We present an efficient algorithm of O(NLw logLw, where N is the length of DNA sequence and Lw is the window length, for identifying repeats. The algorithm operates in two stages. In the first stage, each nucleotide is analyzed separately for periodicity, and in the second stage, the periodic information of each nucleotide is combined together to identify the tandem repeats. Datasets having exact and inexact repeats were taken up for the experimental purpose. The experimental result shows the effectiveness of the approach.

  13. The concordance correlation coefficient for repeated measures estimated by variance components.

    Science.gov (United States)

    Carrasco, Josep L; King, Tonya S; Chinchilli, Vernon M

    2009-01-01

    The concordance correlation coefficient (CCC) is an index that is commonly used to assess the degree of agreement between observers on measuring a continuous characteristic. Here, a CCC for longitudinal repeated measurements is developed through the appropriate specification of the intraclass correlation coefficient from a variance components linear mixed model. A case example and the results of a simulation study are provided.

  14. Measurement repeatability of tibial tuberosity-trochlear groove offset distance in red fox (Vulpes vulpes) cadavers

    NARCIS (Netherlands)

    Miles, J.E.; Jensen, B.R.; Kirpensteijn, J.; Svalastoga, E.L.; Eriksen, T.

    2013-01-01

    Abstract OBJECTIVE: To describe CT image reconstruction criteria for measurement of the tibial tuberosity-trochlear groove (TT-TG) offset distance, evaluate intra- and inter-reconstruction repeatability, and identify key sources of error in the measurement technique, as determined in vulpine hind li

  15. Hierarchical linear model: thinking outside the traditional repeated-measures analysis-of-variance box.

    Science.gov (United States)

    Lininger, Monica; Spybrook, Jessaca; Cheatham, Christopher C

    2015-04-01

    Longitudinal designs are common in the field of athletic training. For example, in the Journal of Athletic Training from 2005 through 2010, authors of 52 of the 218 original research articles used longitudinal designs. In 50 of the 52 studies, a repeated-measures analysis of variance was used to analyze the data. A possible alternative to this approach is the hierarchical linear model, which has been readily accepted in other medical fields. In this short report, we demonstrate the use of the hierarchical linear model for analyzing data from a longitudinal study in athletic training. We discuss the relevant hypotheses, model assumptions, analysis procedures, and output from the HLM 7.0 software. We also examine the advantages and disadvantages of using the hierarchical linear model with repeated measures and repeated-measures analysis of variance for longitudinal data.

  16. Hierarchical Linear Model: Thinking Outside the Traditional Repeated-Measures Analysis-of-Variance Box

    Science.gov (United States)

    Lininger, Monica; Spybrook, Jessaca; Cheatham, Christopher C.

    2015-01-01

    Longitudinal designs are common in the field of athletic training. For example, in the Journal of Athletic Training from 2005 through 2010, authors of 52 of the 218 original research articles used longitudinal designs. In 50 of the 52 studies, a repeated-measures analysis of variance was used to analyze the data. A possible alternative to this approach is the hierarchical linear model, which has been readily accepted in other medical fields. In this short report, we demonstrate the use of the hierarchical linear model for analyzing data from a longitudinal study in athletic training. We discuss the relevant hypotheses, model assumptions, analysis procedures, and output from the HLM 7.0 software. We also examine the advantages and disadvantages of using the hierarchical linear model with repeated measures and repeated-measures analysis of variance for longitudinal data. PMID:25875072

  17. Accuracy and repeatability of a new method for measuring facet loads in the lumbar spine.

    Science.gov (United States)

    Wilson, Derek C; Niosi, Christina A; Zhu, Qingan A; Oxland, Thomas R; Wilson, David R

    2006-01-01

    We assessed the repeatability and accuracy of a relatively new, resistance-based sensor (Tekscan 6900) for measuring lumbar spine facet loads, pressures, and contact areas in cadaver specimens. Repeatability of measurements in the natural facet joint was determined for five trials of four specimens loaded in pure moment (+/- 7.5 N m) flexibility tests in axial rotation and flexion-extension. Accuracy of load measurements in four joints was assessed by applying known compressive loads of 25, 50, and 100 N to the natural facet joint in a materials testing machine and comparing the known applied load to the measured load. Measurements of load were obtained using two different calibration approaches: linear and two-point calibrations. Repeatability for force, pressure, and area (average of standard deviation as a percentage of the mean for all trials over all specimens) was 4-6% for axial rotation and 7-10% for extension. Peak resultant force in axial rotation was 30% smaller when calculated using the linear calibration method. The Tekscan sensor overestimated the applied force by 18 +/- 9% (mean+/-standard deviation), 35 +/- 7% and 50 +/- 9% for compressive loads of 100, 50, and 25 N, respectively. The two-point method overestimated the loads by 35 +/- 16%, 45 +/- 7%, and 56 +/- 10% for the same three loads. Our results show that the Tekscan sensor is repeatable. However, the sensor measurement range is not optimal for the small loads transmitted by the facets and measurement accuracy is highly dependent on calibration protocol.

  18. Power analysis for multivariate and repeated measures designs: a flexible approach using the SPSS MANOVA procedure.

    Science.gov (United States)

    D'Amico, E J; Neilands, T B; Zambarano, R

    2001-11-01

    Although power analysis is an important component in the planning and implementation of research designs, it is often ignored. Computer programs for performing power analysis are available, but most have limitations, particularly for complex multivariate designs. An SPSS procedure is presented that can be used for calculating power for univariate, multivariate, and repeated measures models with and without time-varying and time-constant covariates. Three examples provide a framework for calculating power via this method: an ANCOVA, a MANOVA, and a repeated measures ANOVA with two or more groups. The benefits and limitations of this procedure are discussed.

  19. Repeated quantitative perfusion and contrast permeability measurement in the MRI examination of a CNS tumor

    Energy Technology Data Exchange (ETDEWEB)

    Vonken, E.P.A.; Osch, M.J.P. van; Willems, P.W.A.; Zwan, A. van der; Bakker, C.J.G.; Viergever, M.A.; Mali, W.P.T.M. [University Hospital Utrecht (Netherlands)

    2000-09-01

    This study reports on the results of quantitative MRI perfusion and contrast permeability measurement on two occasions in one patient. The measurements were separated 81 days in time. The tumor grew considerably in this period, but no change was found with respect to perfusion and contrast permeability. Non-involved white matter values were reproduced to demonstrate repeatability. The presented approach to dynamic susceptibility contrast MRI allows fast and repeatable quantitative assessment of perfusion and is easily integrated in a conventional brain tumor protocol. (orig.)

  20. Intraexaminer repeatability and agreement in stereoacuity measurements made in young adults

    Directory of Open Access Journals (Sweden)

    Beatriz Antona

    2015-04-01

    Full Text Available AIM: To determine the repeatability and agreement of stereoacuity measurements made using some of the most widely used clinical tests: Frisby, TNO, Randot and Titmus. METHODS: Stereoacuity was measured in two different sessions separated by a time interval of at least 24h but no longer than 1wk in 74 subjects of mean age 20.6y using the four methods. The study participants were divided into two groups: subjects with normal binocular vision and subjects with abnormal binocular vision. RESULTS: Best repeatability was shown by the Frisby and Titmus [coefficient of repeatability (COR: ±13 and ±12s arc respectively] in the subjects with normal binocular vision though a clear ceiling effect was noted. In the subjects with abnormal binocular vision, best repeatability was shown by the Frisby (COR: ±69s arc and Randot (COR: ±72s arc. In both groups, the TNO test showed poorest agreement with the other tests. CONCLUSION: The repeatability of stereoacuity measures was low in subjects with poor binocular vision yet fairly good in subjects with normal binocular vision with the exception of the TNO test. The reduced agreement detected between the tests indicates they cannot be used interchangeably.

  1. Repeatability of the modified Thorington card used to measure far heterophoria.

    Science.gov (United States)

    Cebrian, Jose Luis; Antona, Beatriz; Barrio, Ana; Gonzalez, Enrique; Gutierrez, Angel; Sanchez, Isabel

    2014-07-01

    To determine the interexaminer and intraexaminer repeatability of the modified Thorington test (TH) for distance vision in young adults and to compare these results with those observed for the heterophoria tests most commonly used in clinical practice. Agreement among tests was also assessed. Distance heterophoria was quantified on two separate occasions by two examiners in 110 subjects aged 18 to 32 years (mean, 19.74 years; SD, 2.5 years) using four different tests: cover test (CT) Von Graefe, Maddox rod, and modified TH. The repeatability of the tests and agreement between them was estimated by the Bland and Altman method whereby the mean difference and the 95% limits of agreement were determined as the coefficient of repeatability (COR) and coefficient of agreement. The Thorington test showed best interexaminer repeatability (COR = ±1.43Δ), followed closely by CT (COR = ±1.65Δ), whereas best intraexaminer repeatability was observed for CT (COR = ±1.28Δ) followed by TH (COR = ±1.51Δ). Among the different combinations of tests, TH and CT showed best agreement indicated by the lowest coefficient of agreement (±2.23Δ) and a low mean difference (-0.63Δ) between measurements. Good interexaminer and intraexaminer repeatability was observed for both TH and CT, and agreement between the two tests was also good. Given the simple administration of the TH, we recommend its clinical use to quantify distance horizontal heterophoria.

  2. Australian House Prices: A Comparison of Hedonic and Repeat-sales Measures

    OpenAIRE

    James Hansen

    2006-01-01

    House prices are intrinsically difficult to measure due to changes in the composition of properties sold through time and changes in the quality of housing. I provide an overview of the theoretical nature of these issues and consider how regression-based measures of house prices – hedonic and repeat-sales measures – can control for compositional and quality change. I then explore whether these regression-based alternatives can provide accurate estimates of pure house price changes in the Aust...

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

    Science.gov (United States)

    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.

  4. Repeatability of cardiac-MRI-measured right ventricular size and function in congenital heart disease

    Energy Technology Data Exchange (ETDEWEB)

    Walsh, Rowan; Salem, Yishay [Mount Sinai School of Medicine, Division of Pediatric Cardiology, New York, NY (United States); Shah, Amee; Lai, Wyman W. [Morgan Stanley Children' s Hospital of New York Presbyterian, New York, NY (United States); Nielsen, James C. [Mount Sinai School of Medicine, Division of Pediatric Cardiology, New York, NY (United States); Mount Sinai Children' s Heart Center, Box 1201, New York, NY (United States)

    2011-08-15

    The measurement error for right ventricular (RV) size and function assessed by cardiac MRI (CMRI) in congenital heart disease has not been fully characterized. As CMRI parameters are being increasingly utilized to make clinical decisions, defining error in the clinical setting is critical. This investigation examines the repeatability of CMRI for RV size and function. Forty consecutive people with congenital heart disease involving the RV were retrospectively identified. Contouring of RV volumes was performed by two expert CMRI clinicians. The coefficient of variability and repeatability coefficients were calculated. Repeatability coefficients were multiplied by the mean value for each group studied to define a threshold beyond which measurement error was unlikely to be responsible. The variability for indexed RV end-diastolic volume = 3.2% and 3.3% for intra- and interobserver comparisons, respectively. The repeatability coefficients were 13.2% and 14.9% for intra- and interobserver comparisons, which yielded threshold values of 15.1 ml/m{sup 2} and 20.2 ml/m{sup 2}, respectively. For RV ejection fraction (EF), the repeatability coefficients for intra- and interobserver comparisons were 5.0% and 6.0%, which resulted in threshold values of 2.6 EF% and 3.0 EF%. The threshold values generated can be used during serial assessment of RV size and function. (orig.)

  5. Accuracy and repeatability of an optical motion analysis system for measuring small deformations of biological tissues.

    Science.gov (United States)

    Liu, Helen; Holt, Cathy; Evans, Sam

    2007-01-01

    Optical motion analysis techniques have been widely used in biomechanics for measuring large-scale motions such as gait, but have not yet been significantly explored for measuring smaller movements such as the tooth displacements under load. In principle, very accurate measurements could be possible and this could provide a valuable tool in many engineering applications. The aim of this study was to evaluate accuracy and repeatability of the Qualisys ProReflex-MCU120 system when measuring small displacements, as a step towards measuring tooth displacements to characterise the properties of the periodontal ligament. Accuracy and repeatability of the system was evaluated using a wedge comparator with a resolution of 0.25 microm to provide measured marker displacements in three orthogonal directions. The marker was moved in ten steps in each direction, for each of seven step sizes (0.5, 1, 2, 3, 5, 10, and 20 microm), repeated five times. Spherical and diamond markers were tested. The system accuracy (i.e. percentage of maximum absolute error in range/measurement range), in the 20-200 microm ranges, was +/-1.17%, +/-1.67% and +/-1.31% for the diamond marker in x, y and z directions, while the system accuracy for the spherical marker was +/-1.81%, +/-2.37% and +/-1.39%. The system repeatability (i.e. maximum standard deviation in the measurement range) measured under the different days, light intensity and temperatures for five times, carried out step up and then step down measurements for the same step size, was +/-1.7, +/-2.3 and +/-1.9 microm for the diamond marker, and +/-2.6, +/-3.9 and +/-1.9 microm for the spherical marker in x, y and z directions, respectively. These results demonstrate that the system suffices accuracy for measuring tooth displacements and could potentially be useful in many other applications.

  6. BIS 220 Tutorials /bis220dotcom

    OpenAIRE

    ramya85

    2015-01-01

    BIS 220 Entire Course   For more course tutorials visit www.bis220.com   BIS 220 Week 1 Individual Assignment Information Technology Acts Paper BIS 220 Week 1 DQ 1 BIS 220 Week 1 DQ 2 BIS 220 Week 2 LT Reflection Summary BIS 220 Week 2 Individual Assignment Information Systems Proposal BIS 220 Week 2 DQ 1 BIS 220 Week 2 DQ 2 BIS 220 Week 3 Individual Assignment Types of Electronic Commerce Activity BIS 220 Week 3 LT Reflection Summ...

  7. BIS 220 Tutorials / bis220dotcom

    OpenAIRE

    rajitha82

    2015-01-01

    BIS 220 Entire Course   For more course tutorials visit www.bis220.com   BIS 220 Week 1 Individual Assignment Information Technology Acts Paper BIS 220 Week 1 DQ 1 BIS 220 Week 1 DQ 2 BIS 220 Week 2 LT Reflection Summary BIS 220 Week 2 Individual Assignment Information Systems Proposal BIS 220 Week 2 DQ 1 BIS 220 Week 2 DQ 2 BIS 220 Week 3 Individual Assignment Types of Electronic Commerce Activity BIS 220 Week 3 LT Reflection Summ...

  8. Repeatability of central corneal thickness measurement with the Pentacam HR system

    Directory of Open Access Journals (Sweden)

    Ruiz Simonato Alonso

    2012-02-01

    Full Text Available PURPOSE: To assess the repeatability of central corneal thickness measurement at the geometrical center (Central Corneal Thickness - CCT given by the Pentacam High Resolution (HR Comprehensive Eye Scanner (Oculus, Wetzlar, Germany over time. METHODS: Prospective, single center, observational study. Two separate CCT measurements were taken by the Pentacam corneal tomography exam (CTm 3 to 12 months apart, and compared. RESULTS: One hundred and sixteen eyes (n=116 of 62 health patients were included in this study. Average CCT in first and last visits was 541.6±37 µm and 543.6±36.9 µm respectively. Mean difference between both measurements was 9.2±6.4 µm, and there was no statistically significant difference in CCT measurement between visits, with good correlation between them (P = 0.057, r² = 0,9209. CONCLUSION: Pentacam (HR CTm gives repeatable CCT measurements over time.

  9. Graphic Methods for Interpreting Longitudinal Dyadic Patterns From Repeated-Measures Actor-Partner Interdependence Models

    DEFF Research Database (Denmark)

    Perry, Nicholas; Baucom, Katherine; Bourne, Stacia

    2017-01-01

    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...

  10. Accuracy and repeatability of anthropometric facial measurements using cone beam computed tomography

    NARCIS (Netherlands)

    Fourie, Zacharias; Damstra, Janalt; Gerrits, Peter O.; Ren, Yijin

    2011-01-01

    Objective: The purpose of this study was to determine the accuracy and repeatability of linear anthropometric measurements on the soft tissue surface model generated from cone beam computed tomography scans. Materials and Methods: The study sample consisted of seven cadaver heads. The accuracy and r

  11. Cross-trimester repeated measures testing for Down's syndrome screening: an assessment.

    LENUS (Irish Health Repository)

    Wright, D

    2010-07-01

    To provide estimates and confidence intervals for the performance (detection and false-positive rates) of screening for Down\\'s syndrome using repeated measures of biochemical markers from first and second trimester maternal serum samples taken from the same woman.

  12. REPEATABILITY OF THE SUGAR ABSORPTION TEST, USING LACTULOSE AND MANNITOL, FOR MEASURING INTESTINAL PERMEABILITY FOR SUGARS

    NARCIS (Netherlands)

    VANELBURG, RM; UIL, JJ; KOKKE, FTM; MULDER, AM; VANDEBROEK, WGM; MULDER, CJJ; HEYMANS, HSA

    1995-01-01

    Differential sugar-absorption tests for measuring intestinal permeability for sugars have been studied in a variety of gastrointestinal diseases. Their use in general practice has been hampered by a lack of data on reference values and repeatability of the test and the laboratory assay. In this stud

  13. The Multilevel Approach to Repeated Measures for Complete and Incomplete Data

    NARCIS (Netherlands)

    Maas, CJM; Snijders, TAB

    2003-01-01

    Repeated measurements often are analyzed by multivariate analysis of variance (MANOVA). An alternative approach is provided by multilevel analysis, also called the hierarchical linear model (HLM), which makes use of random coefficient models. This paper is a tutorial which indicates that the HLM can

  14. Optimal selection of individuals for repeated covariate measurements in follow-up studies.

    Science.gov (United States)

    Reinikainen, Jaakko; Karvanen, Juha; Tolonen, Hanna

    2016-12-01

    Repeated covariate measurements bring important information on the time-varying risk factors in long epidemiological follow-up studies. However, due to budget limitations, it may be possible to carry out the repeated measurements only for a subset of the cohort. We study cost-efficient alternatives for the simple random sampling in the selection of the individuals to be remeasured. The proposed selection criteria are based on forms of the D-optimality. The selection methods are compared with the simulation studies and illustrated with the data from the East-West study carried out in Finland from 1959 to 1999. The results indicate that cost savings can be achieved if the selection is focused on the individuals with high expected risk of the event and, on the other hand, on those with extreme covariate values in the previous measurements. © The Author(s) 2014.

  15. Intraexaminer repeatability and agreement in stereoacuity measurements made in young adults

    Institute of Scientific and Technical Information of China (English)

    Beatriz; Antona; Ana; Barrio; Isabel; Sanchez; Enrique; Gonzalez; Guadalupe; Gonzalez

    2015-01-01

    AIM: To determine the repeatability and agreement of stereoacuity measurements made using some of the most widely used clinical tests: Frisby, TNO, Randot and Titmus.METHODS: Stereoacuity was measured in two different sessions separated by a time interval of at least 24 h but no longer than 1wk in 74 subjects of mean age 20.6y using the four methods. The study participants were divided into two groups: subjects with normal binocular vision and subjects with abnormal binocular vision.RESULTS: Best repeatability was shown by the Frisby and Titmus [coefficient of repeatability(COR): ±13 and±12s arc respectively] in the subjects with normal binocular vision though a clear ceiling effect was noted.In the subjects with abnormal binocular vision, best repeatability was shown by the Frisby(COR: ±69s arc)and Randot(COR: ±72s arc). In both groups, the TNO test showed poorest agreement with the other tests.CONCLUSION:Therepeatabilityofstereoacuitymeasures was low in subjects with poor binocular vision yet fairly good in subjects with normal binocular vision with the exception of the TNO test. The reduced agreement detected between the tests indicates they cannot be used interchangeably.

  16. Repeatability and reproducibility of optic nerve head perfusion measurements using optical coherence tomography angiography

    Science.gov (United States)

    Chen, Chieh-Li; Bojikian, Karine D.; Xin, Chen; Wen, Joanne C.; Gupta, Divakar; Zhang, Qinqin; Mudumbai, Raghu C.; Johnstone, Murray A.; Chen, Philip P.; Wang, Ruikang K.

    2016-06-01

    Optical coherence tomography angiography (OCTA) has increasingly become a clinically useful technique in ophthalmic imaging. We evaluate the repeatability and reproducibility of blood perfusion in the optic nerve head (ONH) measured using optical microangiography (OMAG)-based OCTA. Ten eyes from 10 healthy volunteers are recruited and scanned three times with a 68-kHz Cirrus HD-OCT 5000-based OMAG prototype system (Carl Zeiss Meditec Inc., Dublin, California) centered at the ONH involving two separate visits within six weeks. Vascular images are generated with OMAG processing by detecting the differences in OCT signals between consecutive B-scans acquired at the same retina location. ONH perfusion is quantified as flux, vessel area density, and normalized flux within the ONH for the prelaminar, lamina cribrosa, and the full ONH. Coefficient of variation (CV) and intraclass correlation coefficient (ICC) are used to evaluate intravisit and intervisit repeatability, and interobserver reproducibility. ONH perfusion measurements show high repeatability [CV≤3.7% (intravisit) and ≤5.2% (intervisit)] and interobserver reproducibility (ICC≤0.966) in all three layers by three metrics. OCTA provides a noninvasive method to visualize and quantify ONH perfusion in human eyes with excellent repeatability and reproducibility, which may add additional insight into ONH perfusion in clinical practice.

  17. Repeatability, variability and reference values of pulsed wave Doppler echocardiographic measurements in healthy Saanen goats

    Directory of Open Access Journals (Sweden)

    Leroux Aurélia A

    2012-10-01

    Full Text Available Abstract Background Pulsed wave (PW Doppler echocardiography has become a routine non invasive cardiac diagnostic tool in most species. However, evaluation of intracardiac blood flow requires reference values, which are poorly documented in goats. The aim of this study was to test the repeatability, the variability, and to establish the reference values of PW measurements in healthy adult Saanen goats. Using a standardised PW Doppler echocardiographic protocol, 10 healthy adult unsedated female Saanen goats were investigated three times at one day intervals by the same observer. Mitral, tricuspid, aortic and pulmonary flows were measured from a right parasternal view, and mitral and aortic flows were also measured from a left parasternal view. The difference between left and right side measurements and the intra-observer inter-day repeatability were tested and then the reference values of PW Doppler echocardiographic parameters in healthy adult female Saanen goats were established. Results As documented in other species, all caprine PW Doppler parameters demonstrated a poor inter-day repeatability and a moderate variability. Tricuspid and pulmonary flows were best evaluated on the right side whereas mitral and aortic flows were best obtained on the left side, and reference values are reported for healthy adult Saanen goats. Conclusions PW Doppler echocardiography allows the measurement of intracardiac blood flow indices in goats. The reference values establishment will help interpreting these indices of cardiac function in clinical cardiac cases and developing animal models for human cardiology research.

  18. Using the Monte Carlo Simulation Methods in Gauge Repeatability and Reproducibility of Measurement System Analysis

    Directory of Open Access Journals (Sweden)

    Tsu-Ming Yeh

    2013-10-01

    Full Text Available Measurements are required to maintain the consistent quality of all finished and semi-finished products in a production line. Many firms in the automobile and general precision industries apply the TS 16949:2009 Technical Specifications and Measurement System Analysis (MSA manual to establish measurement systems. This work is undertaken to evaluate gauge repeatability and reproducibility (GR&R to verify the measuring ability and quality of the measurement frame, as well as to continuously improve and maintain the verification process. Nevertheless, the implementation of GR&R requires considerable time and manpower, and is likely to affect production adversely. In addition, the evaluation value for GR&R is always different owing to the sum of man-made and machine-made variations. Using a Monte Carlo simulation and the prediction of the repeatability and reproducibility of the measurement system analysis, this study aims to determine the distribution of %GR&R and the related number of distinct categories (ndc. This study uses two case studies of an automobile parts manufacturer and the combination of a Monte Carlo simulation, statistical bases, and the prediction of the repeatability and reproducibility of the measurement system analysis to determine the probability density function, the distribution of %GR&R, and the related number of distinct categories (ndc. The method used in this study could evaluate effectively the possible range of the GR&R of the measurement capability, in order to establish a prediction model for the evaluation of the measurement capacity of a measurement system.

  19. Antarctic Ice Sheet Slope and Aspect Based on Icesat's Repeat Orbit Measurement

    Science.gov (United States)

    Yuan, L.; Li, F.; Zhang, S.; Xie, S.; Xiao, F.; Zhu, T.; Zhang, Y.

    2017-09-01

    Accurate information of ice sheet surface slope is essential for estimating elevation change by satellite altimetry measurement. A study is carried out to recover surface slope of Antarctic ice sheet from Ice, Cloud and land Elevation Satellite (ICESat) elevation measurements based on repeat orbits. ICESat provides repeat ground tracks within 200 meters in cross-track direction and 170 meters in along-track direction for most areas of Antarctic ice sheet. Both cross-track and along-track surface slopes could be obtained by adjacent repeat ground tracks. Combining those measurements yields a surface slope model with resolution of approximately 200 meters. An algorithm considering elevation change is developed to estimate the surface slope of Antarctic ice sheet. Three Antarctic Digital Elevation Models (DEMs) were used to calculate surface slopes. The surface slopes from DEMs are compared with estimates by using in situ GPS data in Dome A, the summit of Antarctic ice sheet. Our results reveal an average surface slope difference of 0.02 degree in Dome A. High resolution remote sensing images are also used in comparing the results derived from other DEMs and this paper. The comparison implies that our results have a slightly better coherence with GPS observation than results from DEMs, but our results provide more details and perform higher accuracy in coastal areas because of the higher resolution for ICESat measurements. Ice divides are estimated based on the aspect, and are weakly consistent with ice divides from other method in coastal regions.

  20. Body fluid volumes measurements by impedance: A review of bioimpedance spectroscopy (BIS) and bioimpedance analysis (BIA) methods.

    Science.gov (United States)

    Jaffrin, Michel Y; Morel, Hélène

    2008-12-01

    This paper reviews various bioimpedance methods permitting to measure non-invasively, extracellular, intracellular and total body water (TBW) and compares BIA methods based on empirical equations of the wrist-ankle resistance or impedance at 50 kHz, height and weight with BIS methods which rely on an electrical model of tissues and resistances measured at zero and infinite frequencies. In order to compare these methods, impedance measurements were made with a multifrequency Xitron 4200 impedance meter on 57 healthy subjects which had undergone simultaneously a Dual X-ray absorptiometry examination (DXA), in order to estimate their TBW from their fat-free-mass. Extracellular (ECW) and TBW volumes were calculated for these subjects using the original BIS method and modifications of Matthie[Matthie JR. Second generation mixture theory equation for estimating intracellular water using bioimpedance spectroscopy. J Appl Physiol 2005;99:780-1], Jaffrin et al. [Jaffrin MY, Fenech M, Moreno MV, Kieffer R. Total body water measurement by a modification of the bioimpédance spectroscopy method. Med Bio Eng Comput 2006;44:873-82], Moissl et al. [Moissl UM, Wabel P, Chamney PW, Bosaeus I, Levin NW, et al. Body fluid volume determination via body composition spectroscopy in health and disease. Physiol Meas 2006;27:921-33] and their TBW resistivities were compared and discussed. ECW volumes were calculated by BIA methods of Sergi et al. [Sergi G, Bussolotto M, Perini P, Calliari I, et al. Accuracy of bioelectrical bioimpedance analysis for the assessment of extracellular space in healthy subjects and in fluid retention states. Ann Nutr Metab 1994;38(3):158-65] and Hannan et al. [Hannan WJ, Cowen SJ, Fearon KC, Plester CE, Falconer JS, Richardson RA. Evaluation of multi-frequency bio-impedance analysis for the assessment of extracellular and total body water in surgical patients. Clin Sci 1994;86:479-85] and TBW volumes by BIA methods of Kushner and Schoeller [Kushner RF

  1. Validity and repeatability of three in-shoe pressure measurement systems.

    Science.gov (United States)

    Price, Carina; Parker, Daniel; Nester, Christopher

    2016-05-01

    In-shoe pressure measurement devices are used in research and clinic to quantify plantar foot pressures. Various devices are available, differing in size, sensor number and type; therefore accuracy and repeatability. Three devices (Medilogic, Tekscan and Pedar) were examined in a 2 day×3 trial design, quantifying insole response to regional and whole insole loading. The whole insole protocol applied an even pressure (50-600kPa) to the insole surface for 0-30s in the Novel TruBlue™ device. The regional protocol utilised cylinders with contact surfaces of 3.14 and 15.9cm(2) to apply pressures of 50 and 200kPa. The validity (% difference and Root Mean Square Error: RMSE) and repeatability (Intra-Class Correlation Coefficient: ICC) of the applied pressures (whole insole) and contact area (regional) were outcome variables. Validity of the Pedar system was highest (RMSE 2.6kPa; difference 3.9%), with the Medilogic (RMSE 27.0kPa; difference 13.4%) and Tekscan (RMSE 27.0kPa; difference 5.9%) systems displaying reduced validity. The average and peak pressures demonstrated high between-day repeatability for all three systems and each insole size (ICC≥0.859). The regional contact area % difference ranged from -97 to +249%, but the ICC demonstrated medium to high between-day repeatability (ICC≥0.797). Due to the varying responses of the systems, the choice of an appropriate pressure measurement device must be based on the loading characteristics and the outcome variables sought. Medilogic and Tekscan were most effective between 200 and 300kPa; Pedar performed well across all pressures. Contact area was less precise, but relatively repeatable for all systems.

  2. Predicting seed yield in perennial ryegrass using repeated canopy reflectance measurements and PLSR

    DEFF Research Database (Denmark)

    Gislum, René; Deleuran, Lise Christina; Boelt, Birte

    2009-01-01

    Repeated canopy reflectance measurements together with partial least-squares regression (PLSR) were used to predict seed yield in perennial ryegrass (Lolium perenne L.). The measurements were performed during the spring and summer growing seasons of 2001 to 2003 in three field experiments...... reflectance measurements was from approximately 600 cumulative growing degree-days (CGDD) to approximately 900 CGDD. This is the period just before and at heading of the seed crop. Furthermore, regression coefficients showed that information about N and water is important. The results support the development...

  3. REPEATED MEASURES ANALYSIS OF CHANGES IN PHOTOSYNTHETIC EFFICIENCY IN SOUR CHERRY DURING WATER DEFICIT

    Directory of Open Access Journals (Sweden)

    Marija Viljevac

    2012-06-01

    Full Text Available The objective of this study was to investigate changes in photosynthetic efficiency applying repeated measures ANOVA using the photosynthetic performance index (PIABS of the JIP-test as a vitality parameter in seven genotypes of sour cherry (Prunus cerasus, L. during 10 days of continuous water deficit. Both univariate and multivariate ANOVA repeated measures revealed highly significant time effect (Days and its subsequent interactions with genotype and water deficit. However, the multivariate Pillai’s trace test detected the interaction Time × Genotype × Water deficit as not significant. According to the Tukey’s Studentized Range (HSD test, differences between the control and genotypes exposed to water stress became significant on the fourth day of the experiment, indicating that the plants on the average, began to lose their photosynthetic efficiency four days after being exposed to water shortage. It corroborates previous findings in other species that PIABS is very sensitive tool for detecting drought stress.

  4. Status of a UAV SAR Designed for Repeat Pass Interferometry for Deformation Measurements

    Science.gov (United States)

    Hensley, Scott; Wheeler, Kevin; Hoffman, Jim; Miller, Tim; Lou, Yunling; Muellerschoen, Ron; Zebker, Howard; Madsen, Soren; Rosen, Paul

    2004-01-01

    Under the NASA ESTO sponsored Instrument Incubator Program we have designed a lightweight, reconfigurable polarimetric L-band SAR designed for repeat pass deformation measurements of rapidly deforming surfaces of geophysical interest such as volcanoes or earthquakes. This radar will be installed on an unmanned airborne vehicle (UAV) or a lightweight, high-altitude, and long endurance platform such as the Proteus. After a study of suitable available platforms we selected the Proteus for initial development and testing of the system. We want to control the repeat track capability of the aircraft to be within a 10 m tube to support the repeat deformation capability. We conducted tests with the Proteus using real-time GPS with sub-meter accuracy to see if pilots could fly the aircraft within the desired tube. Our results show that pilots are unable to fly the aircraft with the desired accuracy and therefore an augmented autopilot will be required to meet these objectives. Based on the Proteus flying altitude of 13.7 km (45,000 ft), we are designing a fully polarimetric L-band radar with 80 MHz bandwidth and 16 km range swath. This radar will have an active electronic beam steering antenna to achieve Doppler centroid stability that is necessary for repeat-pass interferometry (RPI). This paper will present are design criteria, current design and expected science applications.

  5. Analysis of oligonucleotide array experiments with repeated measures using mixed models

    Directory of Open Access Journals (Sweden)

    Getchell Thomas V

    2004-12-01

    Full Text Available Abstract Background Two or more factor mixed factorial experiments are becoming increasingly common in microarray data analysis. In this case study, the two factors are presence (Patients with Alzheimer's disease or absence (Control of the disease, and brain regions including olfactory bulb (OB or cerebellum (CER. In the design considered in this manuscript, OB and CER are repeated measurements from the same subject and, hence, are correlated. It is critical to identify sources of variability in the analysis of oligonucleotide array experiments with repeated measures and correlations among data points have to be considered. In addition, multiple testing problems are more complicated in experiments with multi-level treatments or treatment combinations. Results In this study we adopted a linear mixed model to analyze oligonucleotide array experiments with repeated measures. We first construct a generalized F test to select differentially expressed genes. The Benjamini and Hochberg (BH procedure of controlling false discovery rate (FDR at 5% was applied to the P values of the generalized F test. For those genes with significant generalized F test, we then categorize them based on whether the interaction terms were significant or not at the α-level (αnew = 0.0033 determined by the FDR procedure. Since simple effects may be examined for the genes with significant interaction effect, we adopt the protected Fisher's least significant difference test (LSD procedure at the level of αnew to control the family-wise error rate (FWER for each gene examined. Conclusions A linear mixed model is appropriate for analysis of oligonucleotide array experiments with repeated measures. We constructed a generalized F test to select differentially expressed genes, and then applied a specific sequence of tests to identify factorial effects. This sequence of tests applied was designed to control for gene based FWER.

  6. Analysis of oligonucleotide array experiments with repeated measures using mixed models.

    Science.gov (United States)

    Li, Hao; Wood, Constance L; Getchell, Thomas V; Getchell, Marilyn L; Stromberg, Arnold J

    2004-12-30

    Two or more factor mixed factorial experiments are becoming increasingly common in microarray data analysis. In this case study, the two factors are presence (Patients with Alzheimer's disease) or absence (Control) of the disease, and brain regions including olfactory bulb (OB) or cerebellum (CER). In the design considered in this manuscript, OB and CER are repeated measurements from the same subject and, hence, are correlated. It is critical to identify sources of variability in the analysis of oligonucleotide array experiments with repeated measures and correlations among data points have to be considered. In addition, multiple testing problems are more complicated in experiments with multi-level treatments or treatment combinations. In this study we adopted a linear mixed model to analyze oligonucleotide array experiments with repeated measures. We first construct a generalized F test to select differentially expressed genes. The Benjamini and Hochberg (BH) procedure of controlling false discovery rate (FDR) at 5% was applied to the P values of the generalized F test. For those genes with significant generalized F test, we then categorize them based on whether the interaction terms were significant or not at the alpha-level (alphanew = 0.0033) determined by the FDR procedure. Since simple effects may be examined for the genes with significant interaction effect, we adopt the protected Fisher's least significant difference test (LSD) procedure at the level of alphanew to control the family-wise error rate (FWER) for each gene examined. A linear mixed model is appropriate for analysis of oligonucleotide array experiments with repeated measures. We constructed a generalized F test to select differentially expressed genes, and then applied a specific sequence of tests to identify factorial effects. This sequence of tests applied was designed to control for gene based FWER.

  7. A Network-Based Algorithm for Clustering Multivariate Repeated Measures Data

    Science.gov (United States)

    Koslovsky, Matthew; Arellano, John; Schaefer, Caroline; Feiveson, Alan; Young, Millennia; Lee, Stuart

    2017-01-01

    The National Aeronautics and Space Administration (NASA) Astronaut Corps is a unique occupational cohort for which vast amounts of measures data have been collected repeatedly in research or operational studies pre-, in-, and post-flight, as well as during multiple clinical care visits. In exploratory analyses aimed at generating hypotheses regarding physiological changes associated with spaceflight exposure, such as impaired vision, it is of interest to identify anomalies and trends across these expansive datasets. Multivariate clustering algorithms for repeated measures data may help parse the data to identify homogeneous groups of astronauts that have higher risks for a particular physiological change. However, available clustering methods may not be able to accommodate the complex data structures found in NASA data, since the methods often rely on strict model assumptions, require equally-spaced and balanced assessment times, cannot accommodate missing data or differing time scales across variables, and cannot process continuous and discrete data simultaneously. To fill this gap, we propose a network-based, multivariate clustering algorithm for repeated measures data that can be tailored to fit various research settings. Using simulated data, we demonstrate how our method can be used to identify patterns in complex data structures found in practice.

  8. High-Dimensional Multivariate Repeated Measures Analysis with Unequal Covariance Matrices

    Science.gov (United States)

    Harrar, Solomon W.; Kong, Xiaoli

    2015-01-01

    In this paper, test statistics for repeated measures design are introduced when the dimension is large. By large dimension is meant the number of repeated measures and the total sample size grow together but either one could be larger than the other. Asymptotic distribution of the statistics are derived for the equal as well as unequal covariance cases in the balanced as well as unbalanced cases. The asymptotic framework considered requires proportional growth of the sample sizes and the dimension of the repeated measures in the unequal covariance case. In the equal covariance case, one can grow at much faster rate than the other. The derivations of the asymptotic distributions mimic that of Central Limit Theorem with some important peculiarities addressed with sufficient rigor. Consistent and unbiased estimators of the asymptotic variances, which make efficient use of all the observations, are also derived. Simulation study provides favorable evidence for the accuracy of the asymptotic approximation under the null hypothesis. Power simulations have shown that the new methods have comparable power with a popular method known to work well in low-dimensional situation but the new methods have shown enormous advantage when the dimension is large. Data from Electroencephalograph (EEG) experiment is analyzed to illustrate the application of the results. PMID:26778861

  9. On the repeated measures designs and sample sizes for randomized controlled trials.

    Science.gov (United States)

    Tango, Toshiro

    2016-04-01

    For the analysis of longitudinal or repeated measures data, generalized linear mixed-effects models provide a flexible and powerful tool to deal with heterogeneity among subject response profiles. However, the typical statistical design adopted in usual randomized controlled trials is an analysis of covariance type analysis using a pre-defined pair of "pre-post" data, in which pre-(baseline) data are used as a covariate for adjustment together with other covariates. Then, the major design issue is to calculate the sample size or the number of subjects allocated to each treatment group. In this paper, we propose a new repeated measures design and sample size calculations combined with generalized linear mixed-effects models that depend not only on the number of subjects but on the number of repeated measures before and after randomization per subject used for the analysis. The main advantages of the proposed design combined with the generalized linear mixed-effects models are (1) it can easily handle missing data by applying the likelihood-based ignorable analyses under the missing at random assumption and (2) it may lead to a reduction in sample size, compared with the simple pre-post design. The proposed designs and the sample size calculations are illustrated with real data arising from randomized controlled trials.

  10. Repeatability and Comparison of Keratometry Values Measured with Potec PRK-6000 Autorefractometer, IOLMaster, and Pentacam

    Directory of Open Access Journals (Sweden)

    Adem Türk

    2014-05-01

    Full Text Available Objectives: To research the repeatability and intercompatibility of keratometry values measured with Potec PRK-6000 autorefractometer, IOL Master, and Pentacam. Materials and Methods: In this prospective study, consecutive measurements were performed in two different sessions with the mentioned three devices on 110 eyes of 55 subjects who had no additional ocular pathology except for refraction error. The consistency of flat and steep keratometry, average keratometry, and corneal astigmatism values obtained in both sessions was compared by using intraclass correlation coefficient (ICC. The measurement differences between the devices were statistically compared as well. Results: The mean age of the study subjects was 23.05±3.01 (18-30 years. ICC values of average keratometry measurements obtained in the sessions were 0.996 for Potec PRK-6000 autorefractometer, 0.997 for IOL Master, and 0.999 for Pentacam. There was high compatibility between the three devices in terms of average keratometry values in Bland-Altman analysis. However, there were statistically significant differences between the devices in terms of parameters other than corneal astigmatism. Conclusion: The repeatability of the three devices was found considerably high in keratometry measurements. However, it is not appropriate for these devices to be substituted for each other in keratometry measurements. (Turk J Ophthalmol 2014; 44: 179-83

  11. Repeatability and Reproducibility of Compression Strength Measurements Conducted According to ASTM E9

    Science.gov (United States)

    Luecke, William E.; Ma, Li; Graham, Stephen M.; Adler, Matthew A.

    2010-01-01

    Ten commercial laboratories participated in an interlaboratory study to establish the repeatability and reproducibility of compression strength tests conducted according to ASTM International Standard Test Method E9. The test employed a cylindrical aluminum AA2024-T351 test specimen. Participants measured elastic modulus and 0.2 % offset yield strength, YS(0.2 % offset), using an extensometer attached to the specimen. The repeatability and reproducibility of the yield strength measurement, expressed as coefficient of variations were cv(sub r)= 0.011 and cv(sub R)= 0.020 The reproducibility of the test across the laboratories was among the best that has been reported for uniaxial tests. The reported data indicated that using diametrically opposed extensometers, instead of a single extensometer doubled the precision of the test method. Laboratories that did not lubricate the ends of the specimen measured yield stresses and elastic moduli that were smaller than those measured in laboratories that lubricated the specimen ends. A finite element analysis of the test specimen deformation for frictionless and perfect friction could not explain the discrepancy, however. The modulus measured from stress-strain data were reanalyzed using a technique that finds the optimal fit range, and applies several quality checks to the data. The error in modulus measurements from stress-strain curves generally increased as the fit range decreased to less than 40 % of the stress range.

  12. The effect of repeated measurements and working memory on the most comfortable level in the ANL test

    DEFF Research Database (Denmark)

    Brännström, K Jonas; Olsen, Steen Østergaard; Holm, Lucas

    2014-01-01

    interleaved methodology during one session using a non-semantic version. Phonological (PWM) and visuospatial working memory (VSWM) was measured. STUDY SAMPLE: Thirty-two normal-hearing adults. RESULTS: Repeated measures ANOVA, intraclass correlations, and the coefficient of repeatability (CR) were used...

  13. Effect of repeated contact on adhesion measurements involving polydimethylsiloxane structural material

    Science.gov (United States)

    Kroner, E.; Maboudian, R.; Arzt, E.

    2009-09-01

    During the last few years several research groups have focused on the fabrication of artificial gecko inspired adhesives. For mimicking these structures, different polymers are used as structure material, such as polydimethylsiloxanes (PDMS), polyurethanes (PU), and polypropylene (PP). While these polymers can be structured easily and used for artificial adhesion systems, the effects of repeated adhesion testing have never been investigated closely. In this paper we report on the effect of repeated adhesion measurements on the commercially available poly(dimethylsiloxane) polymer kit Sylgard 184 (Dow Corning). We show that the adhesion force decreases as a function of contact cycles. The rate of change and the final value of adhesion are found to depend on the details of the PDMS synthesis and structuring.

  14. Effect of repeated contact on adhesion measurements involving polydimethylsiloxane structural material

    Energy Technology Data Exchange (ETDEWEB)

    Kroner, E; Arzt, E [INM-Leibniz Institute for New Materials, Campus D2 2, 66125 Saarbruecken (Germany); Maboudian, R, E-mail: elmar.kroner@inm-gmbh.de [Department of Chem. Eng., 201 Gilman Hall, University of California, Berkeley, CA 94720-1462 (United States)

    2009-09-15

    During the last few years several research groups have focused on the fabrication of artificial gecko inspired adhesives. For mimicking these structures, different polymers are used as structure material, such as polydimethylsiloxanes (PDMS), polyurethanes (PU), and polypropylene (PP). While these polymers can be structured easily and used for artificial adhesion systems, the effects of repeated adhesion testing have never been investigated closely. In this paper we report on the effect of repeated adhesion measurements on the commercially available poly(dimethylsiloxane) polymer kit Sylgard 184 (Dow Corning). We show that the adhesion force decreases as a function of contact cycles. The rate of change and the final value of adhesion are found to depend on the details of the PDMS synthesis and structuring.

  15. Measuring environmental change in forest ecosystems by repeated soil sampling: a North American perspective

    Science.gov (United States)

    Lawrence, Gregory B.; Fernandez, Ivan J.; Richter, Daniel D.; Ross, Donald S.; Hazlett, Paul W.; Bailey, Scott W.; Oiumet, Rock; Warby, Richard A.F.; Johnson, Arthur H.; Lin, Henry; Kaste, James M.; Lapenis, Andrew G.; Sullivan, Timothy J.

    2013-01-01

    Environmental change is monitored in North America through repeated measurements of weather, stream and river flow, air and water quality, and most recently, soil properties. Some skepticism remains, however, about whether repeated soil sampling can effectively distinguish between temporal and spatial variability, and efforts to document soil change in forest ecosystems through repeated measurements are largely nascent and uncoordinated. In eastern North America, repeated soil sampling has begun to provide valuable information on environmental problems such as air pollution. This review synthesizes the current state of the science to further the development and use of soil resampling as an integral method for recording and understanding environmental change in forested settings. The origins of soil resampling reach back to the 19th century in England and Russia. The concepts and methodologies involved in forest soil resampling are reviewed and evaluated through a discussion of how temporal and spatial variability can be addressed with a variety of sampling approaches. Key resampling studies demonstrate the type of results that can be obtained through differing approaches. Ongoing, large-scale issues such as recovery from acidification, long-term N deposition, C sequestration, effects of climate change, impacts from invasive species, and the increasing intensification of soil management all warrant the use of soil resampling as an essential tool for environmental monitoring and assessment. Furthermore, with better awareness of the value of soil resampling, studies can be designed with a long-term perspective so that information can be efficiently obtained well into the future to address problems that have not yet surfaced.

  16. [Repeated measurement of memory with valenced test items: verbal memory, working memory and autobiographic memory].

    Science.gov (United States)

    Kuffel, A; Terfehr, K; Uhlmann, C; Schreiner, J; Löwe, B; Spitzer, C; Wingenfeld, K

    2013-07-01

    A large number of questions in clinical and/or experimental neuropsychology require the multiple repetition of memory tests at relatively short intervals. Studies on the impact of the associated exercise and interference effects on the validity of the test results are rare. Moreover, hardly any neuropsychological instruments exist to date to record the memory performance with several parallel versions in which the emotional valence of the test material is also taken into consideration. The aim of the present study was to test whether a working memory test (WST, a digit-span task with neutral or negative distraction stimuli) devised by our workgroup can be used with repeated measurements. This question was also examined in parallel versions of a wordlist learning paradigm and an autobiographical memory test (AMT). Both tests contained stimuli with neutral, positive and negative valence. Twenty-four participants completed the memory testing including the working memory test and three versions of a wordlist and the AMT at intervals of a week apiece (measuring points 1. - 3.). The results reveal consistent performances across the three measuring points in the working and autobiographical memory test. The valence of the stimulus material did not influence the memory performance. In the delayed recall of the wordlist an improvement in memory performance over time was seen. The tests on working memory presented and the parallel versions for the declarative and autobiographical memory constitute informal economic instruments within the scope of the measurement repeatability designs. While the WST and AMT are appropriate for study designs with repeated measurements at relatively short intervals, longer intervals might seem more favourable for the use of wordlist learning paradigms. © Georg Thieme Verlag KG Stuttgart · New York.

  17. Validity and repeatability of a depth camera-based surface imaging system for thigh volume measurement.

    Science.gov (United States)

    Bullas, Alice M; Choppin, Simon; Heller, Ben; Wheat, Jon

    2016-10-01

    Complex anthropometrics such as area and volume, can identify changes in body size and shape that are not detectable with traditional anthropometrics of lengths, breadths, skinfolds and girths. However, taking these complex with manual techniques (tape measurement and water displacement) is often unsuitable. Three-dimensional (3D) surface imaging systems are quick and accurate alternatives to manual techniques but their use is restricted by cost, complexity and limited access. We have developed a novel low-cost, accessible and portable 3D surface imaging system based on consumer depth cameras. The aim of this study was to determine the validity and repeatability of the system in the measurement of thigh volume. The thigh volumes of 36 participants were measured with the depth camera system and a high precision commercially available 3D surface imaging system (3dMD). The depth camera system used within this study is highly repeatable (technical error of measurement (TEM) of <1.0% intra-calibration and ~2.0% inter-calibration) but systematically overestimates (~6%) thigh volume when compared to the 3dMD system. This suggests poor agreement yet a close relationship, which once corrected can yield a usable thigh volume measurement.

  18. Accuracy and repeatability of an inertial measurement unit system for field-based occupational studies.

    Science.gov (United States)

    Schall, Mark C; Fethke, Nathan B; Chen, Howard; Oyama, Sakiko; Douphrate, David I

    2016-04-01

    The accuracy and repeatability of an inertial measurement unit (IMU) system for directly measuring trunk angular displacement and upper arm elevation were evaluated over eight hours (i) in comparison to a gold standard, optical motion capture (OMC) system in a laboratory setting, and (ii) during a field-based assessment of dairy parlour work. Sample-to-sample root mean square differences between the IMU and OMC system ranged from 4.1° to 6.6° for the trunk and 7.2°-12.1° for the upper arm depending on the processing method. Estimates of mean angular displacement and angular displacement variation (difference between the 90th and 10th percentiles of angular displacement) were observed to change IMU system may serve as an acceptable instrument for directly measuring trunk and upper arm postures in field-based occupational exposure assessment studies with long sampling durations. Practitioner Summary: Few studies have evaluated inertial measurement unit (IMU) systems in the field or over long sampling durations. Results of this study indicate that the IMU system evaluated has reasonably good accuracy and repeatability for use in a field setting over a long sampling duration.

  19. An L-band SAR for repeat pass deformation measurements on a UAV platform

    Science.gov (United States)

    Hensley, Scott; Lou, Yunling; Rosen, Paul; Wheeler, Kevin; Zebker, Howard; Madsen, Soren; Miller, Tim; Hoffman, Jim; Farra, Don

    2003-01-01

    We are proposing to develop a miniaturized polarimetric L-band synthetic aperture radar (SAR) for repeat-pass differential interferometric measurements of deformation for rapidly deforming surfaces of geophysical interest such as volcanoes or earthquakes that is to be flown on a unmanned aerial vehicle (UAV) or minimally piloted vehicle (MPV). Upon surveying the capabilities and availabilities of such aircraft, the Proteus aircraft and the ALTAIR UAV appear to meet our criteria in terms of payload capabilities, flying altitude, and endurance. To support the repeat pass deformation capability it is necessary to control flight track capability of the aircraft to be within a specified 10 m tube with a goal of 1 m. This requires real-time GPS control of the autopilot to achieve these objectives that has not been demonstrated on these aircraft. Based on the Proteus and ALTAIR's altitude of 13.7 km (45,000 ft), we are designing a fully polarimetric L-band radar with 80 MHz bandwidth and a 16 km range swath. The radar will have an active electronic beam steering antenna to achieve a Doppler centroid stability that is necessary for repeat-pass interferometry. This paper presents some of the trade studies for the platform, instrument and the expected science.

  20. Measurement of bedform migration rates on the Lower Missouri River in Missouri, USA using repeat measurements with a multibeam echosounder

    Science.gov (United States)

    Elliott, Caroline M.; Jacobson, Robert B.

    2016-01-01

    High-resolution repeat multibeam echosounder measurements on the Lower Missouri River near Boonville, Missouri, USA show bedform movement and sand storage patterns over daily to seasonal time scales and a range of discharges. Higher flows are frequently, but not always, associated with larger bedforms, higher bedform movement rates, and higher bedload transport rates. Measurements of the temporal and spatial variability in sand dune sizes, transport rates, and sand storage across the river channel have increased understanding of the dynamics of habitats utilized by benthic organisms over multiple life stages and daily to seasonal time scales.

  1. Specific Measurement of Tethered Running Kinetics and its Relationship to Repeated Sprint Ability

    Directory of Open Access Journals (Sweden)

    Sousa Filipe

    2015-12-01

    Full Text Available Repeated sprint ability has been widely studied by researchers, however, analysis of the relationship between most kinetic variables and the effect of fatigue is still an ongoing process. To search for the best biomechanical parameter to evaluate repeated sprint ability, several kinetic variables were measured in a tethered field running test and compared regarding their sensitivity to fatigue and correlation with time trials in a free running condition. Nine male sprint runners (best average times: 100 m = 10.45 ± 0.07 s; 200 m = 21.36 ± 0.17 s; 400 m = 47.35 ± 1.09 s completed two test sessions on a synthetic track. Each session consisted of six 35 m sprints interspersed by 10 s rest under tethered field running or free running conditions. Force, power, work, an impulse and a rate of force development were all directly measured using the sensors of a new tethered running apparatus, and a one-way ANOVA with Scheffé post-hoc test used to verify differences between sprints (p < 0.05. Pearson product-moment correlation measured the relationship between mechanical variables and free running performance. A total impulse, the rate of force development and maximum force did not show significant differences for most sprints. These three variables presented low to moderate correlations with free running performance (r between 0.01 and -0.35. Maximum and mean power presented the strongest correlations with free running performance (r = -0.71 and -0.76, respectively; p < 0.001, followed by mean force (r = -0.61; p < 0.001 and total work (r = -0.50; p < 0.001. It was concluded that under a severe work-to-rest ratio condition, power variables were better suited to evaluating repeated sprint ability than the other studied variables.

  2. Characterisation and measurement of signals generated by DVB-H 'GAP-filler' repeaters.

    Science.gov (United States)

    Baldini, M; Barellini, A; Bogi, L; Licitra, G; Silvi, A M; Zari, A

    2009-12-01

    DVB-H (Digital Video Broadcasting Handheld) is the standard developed by DVB Project and approved by ETSI with the aim of providing the reception of DVB signals even in mobility but also data transfers and multimedia services. The introduction and development of the DVB-H system is still ongoing. In this context, this work focuses on the temporal trend of electromagnetic impact of an urban DVB-H repeater (called 'gap-filler') for exposure assessment purposes; it also describes a method for its measurement by means of narrow band instrumental chains.

  3. Measuring the Activity of Leucine-Rich Repeat Kinase 2: A Kinase Involved in Parkinson's Disease

    Science.gov (United States)

    Lee, Byoung Dae; Li, Xiaojie; Dawson, Ted M.; Dawson, Valina L.

    2015-01-01

    Mutations in the LRRK2 (Leucine-Rich Repeat Kinase 2) gene are the most common cause of autosomal dominant Parkinson's disease. LRRK2 has multiple functional domains including a kinase domain. The kinase activity of LRRK2 is implicated in the pathogenesis of Parkinson's disease. Developing an assay to understand the mechanisms of LRRK2 kinase activity is important for the development of pharmacologic and therapeutic applications. Here, we describe how to measure in vitro LRRK2 kinase activity and its inhibition. PMID:21960214

  4. Iterative Weighted Semiparametric Least Squares Estimation in Repeated Measurement Partially Linear Regression Models

    Institute of Scientific and Technical Information of China (English)

    Ge-mai Chen; Jin-hong You

    2005-01-01

    Consider a repeated measurement partially linear regression model with an unknown vector pasemiparametric generalized least squares estimator (SGLSE) ofβ, we propose an iterative weighted semiparametric least squares estimator (IWSLSE) and show that it improves upon the SGLSE in terms of asymptotic covariance matrix. An adaptive procedure is given to determine the number of iterations. We also show that when the number of replicates is less than or equal to two, the IWSLSE can not improve upon the SGLSE.These results are generalizations of those in [2] to the case of semiparametric regressions.

  5. Measuring Starlight Deflection during the 2017 Eclipse: Repeating the Experiment that made Einstein Famous

    Science.gov (United States)

    Bruns, Donald

    2016-05-01

    In 1919, astronomers performed an experiment during a solar eclipse, attempting to measure the deflection of stars near the sun, in order to verify Einstein's theory of general relativity. The experiment was very difficult and the results were marginal, but the success made Albert Einstein famous around the world. Astronomers last repeated the experiment in 1973, achieving an error of 11%. In 2017, using amateur equipment and modern technology, I plan to repeat the experiment and achieve a 1% error. The best available star catalog will be used for star positions. Corrections for optical distortion and atmospheric refraction are better than 0.01 arcsec. During totality, I expect 7 or 8 measurable stars down to magnitude 9.5, based on analysis of previous eclipse measurements taken by amateurs. Reference images, taken near the sun during totality, will be used for precise calibration. Preliminary test runs performed during twilight in April 2016 and April 2017 can accurately simulate the sky conditions during totality, providing an accurate estimate of the final uncertainty.

  6. Repeatability and Accuracy of Exoplanet Eclipse Depths Measured with Post-Cryogenic Spitzer

    CERN Document Server

    Ingalls, James G; Carey, S J; Stauffer, John R; Lawrence, Patrick J; Grillmair, Carl J; Buzasi, Derek; Deming, Drake; Diamond-Lowe, Hannah; Evans, Thomas M; Morello, G; Stevenson, Kevin B; Wong, Ian; Capak, Peter; Glaccum, William; Laine, Seppo; Surace, Jason; Storrie-Lombardi, Lisa

    2016-01-01

    We examine the repeatability, reliability, and accuracy of differential exoplanet eclipse depth measurements made using the InfraRed Array Camera (IRAC) on the Spitzer Space Telescope during the post-cryogenic mission. We have re-analyzed an existing 4.5{\\mu}m dataset, consisting of 10 observations of the XO-3 b system during secondary eclipse, using 7 different techniques for removing correlated noise. We find that, on average, for a given technique the eclipse depth estimate is repeatable from epoch to epoch to within 150 parts per million (ppm). Most techniques derive eclipse depths that do not vary by more than a factor 2 of the photon noise limit. Nearly all methods accurately assess their own errors: for these methods the individual measurement uncertainties are comparable to the scatter in eclipse depths over the 10-epoch sample. To assess the accuracy of the techniques as well as clarify the difference between instrumental and other sources of measurement error, we have also analyzed a simulated datas...

  7. Repeatability and reproducibility of horizontal corneal diameter and anterior corneal power measurements using the Oculus Keratograph 4

    Directory of Open Access Journals (Sweden)

    Khathutshelo P. Mashige

    2016-03-01

    Full Text Available Purpose: To evaluate the repeatability and reproducibility of horizontal corneal diameter (HCD and anterior corneal power (ACP measurements obtained with the Oculus Keratograph 4 (OCULUS Optikgeräte GmbH.Methods: These parameters (HCD and ACP were prospectively measured in quick succession three times in each of the right eyes of 40 healthy subjects, aged 18–28 years, with normal vision (6/6 or better visual acuity in the first session by a single examiner. Measurements were then repeated in the second session scheduled 1 week later by the same examiner using the same instrument. Repeatability and reproducibility of HCD and ACP measurements was assessed based on the intra-session and intersession within-subject standard deviation (sw, repeatability (2.77sw, coefficient of variation (CoV and intra-class correlation coefficient (ICC.Results: Intra-session repeatability and intersession reproducibility of all measured parameters showed a repeatability (2.77sw of 0.35 mm or less for HCD and 0.35 D or less for ACP, a CoV of 0.30% or less and an ICC of more than 0.9.Conclusion: HCD and ACP measurements obtained using an Oculus Keratograph 4 show good repeatability and reproducibility in healthy eyes; therefore, these parameters can be used for longitudinal follow-up when measured with this device.

  8. Measuring the Dynamic Soil Response During Repeated Wheeling Using Seismic Methods

    DEFF Research Database (Denmark)

    Keller, Thomas; Carizzon, Marco; Berisso, Feto Esimo

    2013-01-01

    Our understanding of soil deformation processes, especially its dynamics, remains limited. This hampers accurate predictions of the impact of soil management practices such as agricultural field traffic on (physical) soil functions. The main objective of this study was to investigate whether...... seismic measurements could be used to assess the dynamic soil behavior during repeated loading. Moreover, we aimed at linking the velocity of P-waves, Vp, to traditionally measured soil properties associated with soil compaction, namely bulk density (ρb) and penetrometer resistance. A wheeling experiment......, and simulated the evolution of bulk density due to the wheeling using a soil compaction model. The dynamic soil response during loading–unloading–reloading cycles could be well captured with the seismic method. The measured Vp related to bulk density, and the compaction-induced increase in Vp correlated...

  9. Russian Laminar Flow Airfoils 3rd Part: Measurements on the Profile No. 2315 BIS with Ava-Nose Flap

    Science.gov (United States)

    Riegels, F.

    1947-01-01

    The tests on the Russian airfoil 2315 Bis were continued. This airfoil shows, according to Moscow tests, good laminar flow characteristics. Several tests were prepared in the large wind tunnel at Gottingen; partial results were obtained.

  10. Information Contents of a Signal at Repeated Positioning Measurements of the Coordinate Measuring Machine (CMM by Laser Interferometer

    Directory of Open Access Journals (Sweden)

    Stejskal Tomáš

    2016-10-01

    Full Text Available The input of this paper lies in displaying possibilities how to determine the condition of a coordinate measuring machine (CMM based on a large number of repeated measurements. The number of repeated measurements exceeds common requirements for determining positioning accuracy. The total offset in the accuracy of spatial positioning consists of partial inaccuracies of individual axes. 6 basic errors may be defined at each axis. In a triaxial set, that translates into 18 errors, to which an offset from the perpendicularity between the axial pairs must be added. Therefore, the combined number of errors in a single position is 21. These errors are systemic and stem from the machine’s geometry. In addition, there are accidental errors to account for as well. Accidental errors can be attributed to vibrations, mass inertness, passive resistance, and in part to fluctuations in temperature. A peculiar set of systemic errors are time-varying errors. The nature of those errors may be reversible, for instance if they result from influence of temperature or elastic deformation. They can be also irreversible, for example as a result of wear and tear or line clogging, due to loosened connection or permanent deformation of a part post collision. A demonstration of thermal equalizing of the machine’s parts may also be observed in case of failure to adhere to a sufficient time interval from the moment the air-conditioning is turned on. Repeated measurements done on a selected axis with linear interferometer can provide complex information on the CMM condition and also on the machine’s interaction with the given technical environment.

  11. Specific Measurement of Tethered Running Kinetics and its Relationship to Repeated Sprint Ability.

    Science.gov (United States)

    Sousa, Filipe; Dos Reis, Ivan; Ribeiro, Luiz; Martins, Luiz; Gobatto, Claudio

    2015-12-22

    Repeated sprint ability has been widely studied by researchers, however, analysis of the relationship between most kinetic variables and the effect of fatigue is still an ongoing process. To search for the best biomechanical parameter to evaluate repeated sprint ability, several kinetic variables were measured in a tethered field running test and compared regarding their sensitivity to fatigue and correlation with time trials in a free running condition. Nine male sprint runners (best average times: 100 m = 10.45 ± 0.07 s; 200 m = 21.36 ± 0.17 s; 400 m = 47.35 ± 1.09 s) completed two test sessions on a synthetic track. Each session consisted of six 35 m sprints interspersed by 10 s rest under tethered field running or free running conditions. Force, power, work, an impulse and a rate of force development were all directly measured using the sensors of a new tethered running apparatus, and a one-way ANOVA with Scheffé post-hoc test used to verify differences between sprints (p sprints. These three variables presented low to moderate correlations with free running performance (r between 0.01 and -0.35). Maximum and mean power presented the strongest correlations with free running performance (r = -0.71 and -0.76, respectively; p sprint ability than the other studied variables.

  12. On the Analysis of a Repeated Measure Design in Genome-Wide Association Analysis

    Directory of Open Access Journals (Sweden)

    Young Lee

    2014-11-01

    Full Text Available Longitudinal data enables detecting the effect of aging/time, and as a repeated measures design is statistically more efficient compared to cross-sectional data if the correlations between repeated measurements are not large. In particular, when genotyping cost is more expensive than phenotyping cost, the collection of longitudinal data can be an efficient strategy for genetic association analysis. However, in spite of these advantages, genome-wide association studies (GWAS with longitudinal data have rarely been analyzed taking this into account. In this report, we calculate the required sample size to achieve 80% power at the genome-wide significance level for both longitudinal and cross-sectional data, and compare their statistical efficiency. Furthermore, we analyzed the GWAS of eight phenotypes with three observations on each individual in the Korean Association Resource (KARE. A linear mixed model allowing for the correlations between observations for each individual was applied to analyze the longitudinal data, and linear regression was used to analyze the first observation on each individual as cross-sectional data. We found 12 novel genome-wide significant disease susceptibility loci that were then confirmed in the Health Examination cohort, as well as some significant interactions between age/sex and SNPs.

  13. Multiple-objective response-adaptive repeated measurement designs in clinical trials for binary responses.

    Science.gov (United States)

    Liang, Yuanyuan; Li, Yin; Wang, Jing; Carriere, Keumhee C

    2014-02-20

    A multiple-objective allocation strategy was recently proposed for constructing response-adaptive repeated measurement designs for continuous responses. We extend the allocation strategy to constructing response-adaptive repeated measurement designs for binary responses. The approach with binary responses is quite different from the continuous case, as the information matrix is a function of responses, and it involves nonlinear modeling. To deal with these problems, we first build the design on the basis of success probabilities. Then we illustrate how various models can accommodate carryover effects on the basis of logits of response profiles as well as any correlation structure. Through computer simulations, we find that the allocation strategy developed for continuous responses also works well for binary responses. As expected, design efficiency in terms of mean squared error drops sharply, as more emphasis is placed on increasing treatment benefit than estimation precision. However, we find that it can successfully allocate more patients to better treatment sequences without sacrificing much estimation precision.

  14. Role of Repeat Muscle Compartment Pressure Measurements in Chronic Exertional Compartment Syndrome of the Lower Leg

    Science.gov (United States)

    van Zantvoort, Aniek P. M.; de Bruijn, Johan A.; Winkes, Michiel B.; Hoogeveen, Adwin R.; Teijink, Joep A. W.; Scheltinga, Marc R.

    2017-01-01

    Background: The diagnostic gold standard for diagnosing chronic exertional compartment syndrome (CECS) is a dynamic intracompartmental pressure (ICP) measurement of the muscle. The potential role of a repeat ICP (re-ICP) measurement in patients with persistent lower leg symptoms after surgical decompression or with ongoing symptoms after an earlier normal ICP is unknown. Purpose: To study whether re-ICP measurements in patients with persistent CECS-like symptoms of the lower leg may contribute to the diagnosis of CECS after both surgical decompression and a previously normal ICP measurement. Study Design: Case series; Level of evidence, 4. Methods: Charts of patients who underwent re-ICP measurement of lower leg compartments (anterior [ant], deep posterior [dp], and/or lateral [lat] compartments) between 2001 and 2013 were retrospectively studied. CECS was diagnosed on the basis of generally accepted cutoff pressures for newly onset CECS (Pedowitz criteria: ICP at rest ≥15 mmHg, ≥30 mmHg after 1 minute, or ≥20 mmHg 5 minutes after a provocative test). Factors predicting recurrent CECS after surgery or after a previously normal ICP measurement were analyzed. Results: A total of 1714 ICP measurements were taken in 1513 patients with suspected CECS over a 13-year observation period. In all, 201 (12%) tests were re-ICP measurements for persistent lower leg symptoms. Based on the proposed ICP cutoff values, CECS recurrence was diagnosed in 16 of 62 previously operated compartments (recurrence rate, 26%; 53 patients [64% female]; median age, 24 years; age range, 15-78 years). Recurrence rates were not different among the 3 lower leg CECS compartments (ant-CECS, 17%; dp-CECS, 33%; lat-CECS, 30%; χ2 = 1.928, P = .381). Sex (χ2 = 0.058, P = .810), age (U = 378, z = 1.840, P = .066), bilaterality (χ2 = 0.019, P = .889), and prefasciotomy ICP did not predict recurrence. Re-ICP measurements evaluating 20 compartments with previously normal ICP measurements (15

  15. Role of Repeat Muscle Compartment Pressure Measurements in Chronic Exertional Compartment Syndrome of the Lower Leg.

    Science.gov (United States)

    van Zantvoort, Aniek P M; de Bruijn, Johan A; Winkes, Michiel B; Hoogeveen, Adwin R; Teijink, Joep A W; Scheltinga, Marc R

    2017-06-01

    The diagnostic gold standard for diagnosing chronic exertional compartment syndrome (CECS) is a dynamic intracompartmental pressure (ICP) measurement of the muscle. The potential role of a repeat ICP (re-ICP) measurement in patients with persistent lower leg symptoms after surgical decompression or with ongoing symptoms after an earlier normal ICP is unknown. To study whether re-ICP measurements in patients with persistent CECS-like symptoms of the lower leg may contribute to the diagnosis of CECS after both surgical decompression and a previously normal ICP measurement. Case series; Level of evidence, 4. Charts of patients who underwent re-ICP measurement of lower leg compartments (anterior [ant], deep posterior [dp], and/or lateral [lat] compartments) between 2001 and 2013 were retrospectively studied. CECS was diagnosed on the basis of generally accepted cutoff pressures for newly onset CECS (Pedowitz criteria: ICP at rest ≥15 mmHg, ≥30 mmHg after 1 minute, or ≥20 mmHg 5 minutes after a provocative test). Factors predicting recurrent CECS after surgery or after a previously normal ICP measurement were analyzed. A total of 1714 ICP measurements were taken in 1513 patients with suspected CECS over a 13-year observation period. In all, 201 (12%) tests were re-ICP measurements for persistent lower leg symptoms. Based on the proposed ICP cutoff values, CECS recurrence was diagnosed in 16 of 62 previously operated compartments (recurrence rate, 26%; 53 patients [64% female]; median age, 24 years; age range, 15-78 years). Recurrence rates were not different among the 3 lower leg CECS compartments (ant-CECS, 17%; dp-CECS, 33%; lat-CECS, 30%; χ(2) = 1.928, P = .381). Sex (χ(2) = 0.058, P = .810), age (U = 378, z = 1.840, P = .066), bilaterality (χ(2) = 0.019, P = .889), and prefasciotomy ICP did not predict recurrence. Re-ICP measurements evaluating 20 compartments with previously normal ICP measurements (15 patients [53% female]; mean age, 31 ± 10 years

  16. ±25ppm repeatable measurement of trapezoidal pulses with 5MHz bandwidth

    CERN Document Server

    AUTHOR|(SzGeCERN)712364; Arpaia, Pasquale; Cerqueira Bastos, Miguel; Martino, Michele

    2015-01-01

    High-quality measurements of pulses are nowadays widely used in fields such as radars, pulsed lasers, electromagnetic pulse generators, and particle accelerators. Whilst literature is mainly focused on fast systems for nanosecond regime with relaxed metrological requirements, in this paper, the high-performance measurement of slower pulses in microsecond regime is faced. In particular, the experimental proof demonstration for a 15 MS/s,_25 ppm repeatable acquisition system to characterize the flat-top of 3 ms rise-time trapezoidal pulses is given. The system exploits a 5MHz bandwidth circuit for analogue signal processing based on the concept of flat-top removal. The requirements, as well as the conceptual and physical designs are illustrated. Simulation results aimed at assessing the circuit performance are also presented. Finally, an experimental case study on the characterization of a pulsed power supply for the klystrons modulators of the Compact Linear Collider (CLIC) under study at CERN is reported. In ...

  17. Alcohol intake and colorectal cancer: a comparison of approaches for including repeated measures of alcohol consumption

    DEFF Research Database (Denmark)

    Thygesen, Lau Caspar; Wu, Kana; Grønbaek, Morten

    2008-01-01

    BACKGROUND: In numerous studies, alcohol intake has been found to be positively associated with colorectal cancer risk. However, the majority of studies included only one exposure measurement, which may bias the results if long-term intake is relevant.METHODS: We compared different approaches...... for including repeated measures of alcohol intake among 47,432 US men enrolled in the Health Professionals Follow-up Study. Questionnaires including questions on alcohol intake had been completed in 1986, 1990, 1994, and 1998. The outcome was incident colorectal cancer during follow-up from 1986 to 2002.RESULTS......: During follow-up, 868 members of the cohort experienced colorectal cancer. Baseline, updated, and cumulative average alcohol intakes were positively associated with colorectal cancer, with only minor differences among the approaches. These results support moderately increased risk for intake >30 g...

  18. Impact of repeated measures and sample selection on genome-wide association studies of fasting glucose

    Science.gov (United States)

    Rasmussen-Torvik, Laura J.; Alonso, Alvaro; Li, Man; Kao, Wen; Köttgen, Anna; Yan, Yuer; Couper, David; Boerwinkle, Eric; Bielinski, Suzette J.; Pankow, James S.

    2010-01-01

    Although GWAS have been performed in longitudinal studies, most used only a single trait measure. GWAS of fasting glucose have generally included only normoglycemic individuals. We examined the impact of both repeated measures and sample selection on GWAS in ARIC, a study which obtained four longitudinal measures of fasting glucose and included both individuals with and without prevalent diabetes. The sample included Caucasians and the Affymetrix 6.0 chip was used for genotyping. Sample sizes for GWAS analyses ranged from 8372 (first study visit) to 5782 (average fasting glucose). Candidate SNP analyses with SNPs identified through fasting glucose or diabetes GWAS were conducted in 9133 individuals, including 761 with prevalent diabetes. For a constant sample size, smaller p-values were obtained for the average measure of fasting glucose compared to values at any single visit, and two additional significant GWAS signals were detected. For four candidate SNPs (rs780094, rs10830963, rs7903146, and rs4607517), the strength of association between genotype and glucose was significantly (p-interaction fasting glucose candidate SNPs (rs780094, rs10830963, rs560887, rs4607517, rs13266634) the association with measured fasting glucose was more significant in the smaller sample without prevalent diabetes than in the larger combined sample of those with and without diabetes. This analysis demonstrates the potential utility of averaging trait values in GWAS studies and explores the advantage of using only individuals without prevalent diabetes in GWAS of fasting glucose. PMID:20839289

  19. Estimation of the concordance correlation coefficient for repeated measures using SAS and R.

    Science.gov (United States)

    Carrasco, Josep L; Phillips, Brenda R; Puig-Martinez, Josep; King, Tonya S; Chinchilli, Vernon M

    2013-03-01

    The concordance correlation coefficient is one of the most common approaches used to assess agreement among different observers or instruments when the outcome of interest is a continuous variable. A SAS macro and R package are provided here to estimate the concordance correlation coefficient (CCC) where the design of the data involves repeated measurements by subject and observer. The CCC is estimated using U-statistics (UST) and variance components (VC) approaches. Confidence intervals and standard errors are reported along with the point estimate of the CCC. In the case of the VC approach, the linear mixed model output and variance components estimates are also provided. The performance of each function is shown by means of some examples with real data sets.

  20. Graphic Methods for Interpreting Longitudinal Dyadic Patterns From Repeated-Measures Actor-Partner Interdependence Models

    DEFF Research Database (Denmark)

    Perry, Nicholas; Baucom, Katherine; Bourne, Stacia

    2017-01-01

    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...... 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...

  1. Inmate responses to prison-based drug treatment: a repeated measures analysis.

    Science.gov (United States)

    Welsh, Wayne N

    2010-06-01

    Using a sample of 347 prison inmates and general linear modeling (GLM) repeated measures analyses, this paper examined during-treatment responses (e.g., changes in psychological and social functioning) to prison-based TC drug treatment. These effects have rarely been examined in previous studies, and never with a fully multivariate model accounting for within-subjects effects (changes over time), between-subjects effects (e.g., levels of risk and motivation), and within/between-subjects interactions (timexriskxmotivation). The results provide evidence of positive inmate change in response to prison TC treatment, but the patterns of results varied depending upon: (a) specific indicators of psychological and social functioning, motivation, and treatment process; (b) the time periods examined (1, 6, and 12 months during treatment); and (c) baseline levels of risk and motivation. Significant interactions between time and type of inmate suggest important new directions for research, theory, and practice in offender-based substance abuse treatment.

  2. Bayesian latent variable models for hierarchical clustered count outcomes with repeated measures in microbiome studies.

    Science.gov (United States)

    Xu, Lizhen; Paterson, Andrew D; Xu, Wei

    2017-04-01

    Motivated by the multivariate nature of microbiome data with hierarchical taxonomic clusters, counts that are often skewed and zero inflated, and repeated measures, we propose a Bayesian latent variable methodology to jointly model multiple operational taxonomic units within a single taxonomic cluster. This novel method can incorporate both negative binomial and zero-inflated negative binomial responses, and can account for serial and familial correlations. We develop a Markov chain Monte Carlo algorithm that is built on a data augmentation scheme using Pólya-Gamma random variables. Hierarchical centering and parameter expansion techniques are also used to improve the convergence of the Markov chain. We evaluate the performance of our proposed method through extensive simulations. We also apply our method to a human microbiome study.

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

    Science.gov (United States)

    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.

  4. Microcomputer-based tests for repeated-measures: Metric properties and predictive validities

    Science.gov (United States)

    Kennedy, Robert S.; Baltzley, Dennis R.; Dunlap, William P.; Wilkes, Robert L.; Kuntz, Lois-Ann

    1989-01-01

    A menu of psychomotor and mental acuity tests were refined. Field applications of such a battery are, for example, a study of the effects of toxic agents or exotic environments on performance readiness, or the determination of fitness for duty. The key requirement of these tasks is that they be suitable for repeated-measures applications, and so questions of stability and reliability are a continuing, central focus of this work. After the initial (practice) session, seven replications of 14 microcomputer-based performance tests (32 measures) were completed by 37 subjects. Each test in the battery had previously been shown to stabilize in less than five 90-second administrations and to possess retest reliabilities greater than r = 0.707 for three minutes of testing. However, all the tests had never been administered together as a battery and they had never been self-administered. In order to provide predictive validity for intelligence measurement, the Wechsler Adult Intelligence Scale-Revised and the Wonderlic Personnel Test were obtained on the same subjects.

  5. Characterization of the peripheral blood transcriptome in a repeated measures design using a panel of healthy individuals

    DEFF Research Database (Denmark)

    De Boever, Patrick; Wens, Britt; Forcheh, Anyiawung Chiara

    2014-01-01

    A repeated measures microarray design with 22 healthy, non-smoking volunteers (aging 32. ±. 5. years) was set up to study transcriptome profiles in whole blood samples. The results indicate that repeatable data can be obtained with high within-subject correlation. Probes that could discriminate....... Our study suggests that the blood transcriptome of healthy individuals is reproducible over a time period of several months. © 2013 Elsevier Inc....

  6. Status of a UAVSAR designed for repeat pass interferometry for deformation measurements

    Science.gov (United States)

    Hensley, Scott; Wheeler, Kevin; Sadowy, Greg; Miller, Tim; Shaffer, Scott; Muellerschoen, Ron; Jones, Cathleen; Zebker, Howard; Madsen, Soren; Paul, Rose

    2005-01-01

    NASA's Jet Propulsion Laboratory is currently implementing a reconfigurable polarimetric L-band synthetic aperture radar (SAR), specifically designed to acquire airborne repeat track interferometric (RTI) SAR data, also known as differential interferometric measurements. Differential interferometry can provide key deformation measurements, important for the scientific studies of Earthquakes and volcanoes. Using precision real-time GPS and a sensor controlled flight management system, the system will be able to fly predefined paths with great precision. The expected performance of the flight control system will constrain the flight path to be within a 10 m diameter tube about the desired flight track. The radar wilI be designed to operate on a UAV (Unpiloted Aria1 Vehicle) but will initially be demonstrated on a minimally piloted vehicle (MPV), such as the Proteus buitt by Scaled Composites or on a NASA Gulfstream III. The radar design is a fully polarimetric with an 80 MHz bandwidth (2 m range resolution) and 16 km range swath. The antenna is an electronically steered along track to assure that the actual antenna pointing can be controlled independent of the wind direction and speed. Other features supported by the antenna include an elevation monopulse option and a pulse-to-pulse resteering capability that will enable some novel modes of operation. The system will nominally operate at 45,000 ft (13800 m). The program began out as an Instrument Incubator Project (IIP) funded by NASA Earth Science and Technology Office (ESTO).

  7. Repeated measures of serum glucose and insulin in relation to postmenopausal breast cancer.

    Science.gov (United States)

    Kabat, Geoffrey C; Kim, Mimi; Caan, Bette J; Chlebowski, Rowan T; Gunter, Marc J; Ho, Gloria Y F; Rodriguez, Beatriz L; Shikany, James M; Strickler, Howard D; Vitolins, Mara Z; Rohan, Thomas E

    2009-12-01

    Experimental and epidemiological evidence suggests that circulating glucose and insulin may play a role in breast carcinogenesis. However, few cohort studies have examined breast cancer risk in association with glucose and insulin levels, and studies to date have had only baseline measurements of exposure. We conducted a longitudinal study of postmenopausal breast cancer risk using the 6% random sample of women in the Women's Health Initiative clinical trials whose fasting blood samples, provided at baseline and at years 1, 3 and 6, were analyzed for glucose and insulin. In addition, a 1% sample of women in the observational study, who had glucose and insulin measured in fasting blood samples drawn at baseline and in year 3, were included in the analysis. We used Cox proportional hazards models to estimate hazard ratios and 95% confidence intervals for the association of baseline and follow-up measurements of serum glucose and insulin with breast cancer risk. All statistical tests were 2-sided. Among 5,450 women with baseline serum glucose and insulin values, 190 incident cases of breast cancer were ascertained over a median of 8.0 years of follow-up. The highest tertile of baseline insulin, relative to the lowest, was associated with a 2-fold increase in risk in the total population (multivariable hazard ratio 2.22, 95% confidence interval 1.39-3.53) and with a 3-fold increase in risk in women who were not enrolled in the intervention arm of any clinical trial (multivariable hazard ratio 3.15, 95% confidence interval 1.61-6.17). Glucose levels showed no association with risk. Analysis of the repeated measurements supported the results of the baseline analysis. These data suggest that elevated serum insulin levels may be a risk factor for postmenopausal breast cancer.

  8. Repeated Blood Pressure Measurements in Childhood in Prediction of Hypertension in Adulthood.

    Science.gov (United States)

    Oikonen, Mervi; Nuotio, Joel; Magnussen, Costan G; Viikari, Jorma S A; Taittonen, Leena; Laitinen, Tomi; Hutri-Kähönen, Nina; Jokinen, Eero; Jula, Antti; Cheung, Michael; Sabin, Matthew A; Daniels, Stephen R; Raitakari, Olli T; Juonala, Markus

    2016-01-01

    Hypertension may be predicted from childhood risk factors. Repeated observations of abnormal blood pressure in childhood may enhance prediction of hypertension and subclinical atherosclerosis in adulthood compared with a single observation. Participants (1927, 54% women) from the Cardiovascular Risk in Young Finns Study had systolic and diastolic blood pressure measurements performed when aged 3 to 24 years. Childhood/youth abnormal blood pressure was defined as above 90th or 95th percentile. After a 21- to 31-year follow-up, at the age of 30 to 45 years, hypertension (>140/90 mm Hg or antihypertensive medication) prevalence was found to be 19%. Carotid intima-media thickness was examined, and high-risk intima-media was defined as intima-media thickness >90th percentile or carotid plaques. Prediction of adulthood hypertension and high-risk intima-media was compared between one observation of abnormal blood pressure in childhood/youth and multiple observations by improved Pearson correlation coefficients and area under the receiver operating curve. When compared with a single measurement, 2 childhood/youth observations improved the correlation for adult systolic (r=0.44 versus 0.35, Ppressure. In addition, 2 abnormal childhood/youth blood pressure observations increased the prediction of hypertension in adulthood (0.63 for 2 versus 0.60 for 1 observation, P=0.003). When compared with 2 measurements, third observation did not provide any significant improvement for correlation or prediction (P always >0.05). A higher number of childhood/youth observations of abnormal blood pressure did not enhance prediction of adult high-risk intima-media thickness. Compared with a single measurement, the prediction of adult hypertension was enhanced by 2 observations of abnormal blood pressure in childhood/youth. © 2015 American Heart Association, Inc.

  9. Corneal Topographic and Aberrometric Measurements Obtained with a Multidiagnostic Device in Healthy Eyes: Intrasession Repeatability

    Directory of Open Access Journals (Sweden)

    David P. Piñero

    2017-01-01

    Full Text Available Purpose. To evaluate the intrasession repeatability of corneal curvature, eccentricity, and aberrometric measurements obtained with a multidiagnostic device in healthy eyes. Methods. This study enrolled 107 eyes of 107 patients ranging in age from 23 to 65 years. All of them underwent a complete anterior segment examination with the VX120 system (Visionix-Luneau Technologies, Chartres, France. Three consecutive measurements were obtained. The within-subject standard deviation (Sw, intrasubject precision (1.96×Sw, and intraclass correlation coefficient (ICC were calculated. Results. All Sw for corneal power measurements were below 0.26 D, with ICC above 0.982. The Sw for corneal astigmatism at different areas (3, 5, and 7 mm was below 0.21 D, with ICC above 0.913. Concerning the axis of astigmatism, its Sw was below 11.27°, with ICC above 0.975. The Sw and ICC for corneal eccentricity were 0.067 and 0.957, respectively. The Sw and ICC for high-order aberration root mean square (RMS were 0.048 µm and 0.901, respectively. For 3rd- and 4th-order aberrometric parameters, all Sw were below 0.037 µm and all ICC were higher than 0.84, except for quadrafoil RMS (ICC: 0.689. Conclusions. The multidiagnostic device evaluated is able to provide consistent measurements of corneal power, eccentricity, and third- and fourth-order aberrations in healthy eyes.

  10. Measurement of repeat effects in Chicago’s criminal social network

    Directory of Open Access Journals (Sweden)

    Paul Kump

    2016-07-01

    Full Text Available The “near-repeat” effect is a well-known criminological phenomenon in which the occurrence of a crime incident gives rise to a temporary elevation of crime risk within close physical proximity to an initial incident. Adopting a social network perspective, we instead define a near repeat in terms of geodesic distance within a criminal social network, rather than spatial distance. Specifically, we report a statistical analysis of repeat effects in arrest data for Chicago during the years 2003–2012. We divide the arrest data into two sets (violent crimes and other crimes and, for each set, we compare the distributions of time intervals between repeat incidents to theoretical distributions in which repeat incidents occur only by chance. We first consider the case of the same arrestee participating in repeat incidents (“exact repeats” and then extend the analysis to evaluate repeat risks of those arrestees near one another in the social network. We observe repeat effects that diminish as a function of geodesic distance and time interval, and we estimate typical time scales for repeat crimes in Chicago.

  11. Constructing Measure by Repeated Infinite Subdivision%通过反复无限细分定义测度

    Institute of Scientific and Technical Information of China (English)

    严质彬

    2005-01-01

    This paper generalizes the method of constructing measure by repeated finite subdivision in fTactal geometry to that by infinite subdivision. Two conditions for the existing method are removed. A measure on the interval [0, 1] is constructed using this generalized method.

  12. Cardiometabolic treatment decisions in patients with type 2 diabetes : the role of repeated measurements and medication burden

    NARCIS (Netherlands)

    Voorham, J.; Haaijer-Ruskamp, F. M.; Wolffenbuttel, B. H. R.; Stolk, R. P.; Denig, P.

    2010-01-01

    Purpose Clinical guidelines for cardiometabolic risk management indicate a simple threshold-based strategy for treatment, but physicians and their patients may be reluctant to modify drug treatment after a single elevated measurement. We determined how repeated measurements of blood pressure, choles

  13. Cardiometabolic treatment decisions in patients with type 2 diabetes : the role of repeated measurements and medication burden

    NARCIS (Netherlands)

    Voorham, J.; Haaijer-Ruskamp, F. M.; Wolffenbuttel, B. H. R.; Stolk, R. P.; Denig, P.

    2010-01-01

    Purpose Clinical guidelines for cardiometabolic risk management indicate a simple threshold-based strategy for treatment, but physicians and their patients may be reluctant to modify drug treatment after a single elevated measurement. We determined how repeated measurements of blood pressure,

  14. Tracking photon jumps with repeated quantum non-demolition parity measurements.

    Science.gov (United States)

    Sun, L; Petrenko, A; Leghtas, Z; Vlastakis, B; Kirchmair, G; Sliwa, K M; Narla, A; Hatridge, M; Shankar, S; Blumoff, J; Frunzio, L; Mirrahimi, M; Devoret, M H; Schoelkopf, R J

    2014-07-24

    Quantum error correction is required for a practical quantum computer because of the fragile nature of quantum information. In quantum error correction, information is redundantly stored in a large quantum state space and one or more observables must be monitored to reveal the occurrence of an error, without disturbing the information encoded in an unknown quantum state. Such observables, typically multi-quantum-bit parities, must correspond to a special symmetry property inherent in the encoding scheme. Measurements of these observables, or error syndromes, must also be performed in a quantum non-demolition way (projecting without further perturbing the state) and more quickly than errors occur. Previously, quantum non-demolition measurements of quantum jumps between states of well-defined energy have been performed in systems such as trapped ions, electrons, cavity quantum electrodynamics, nitrogen-vacancy centres and superconducting quantum bits. So far, however, no fast and repeated monitoring of an error syndrome has been achieved. Here we track the quantum jumps of a possible error syndrome, namely the photon number parity of a microwave cavity, by mapping this property onto an ancilla quantum bit, whose only role is to facilitate quantum state manipulation and measurement. This quantity is just the error syndrome required in a recently proposed scheme for a hardware-efficient protected quantum memory using Schrödinger cat states (quantum superpositions of different coherent states of light) in a harmonic oscillator. We demonstrate the projective nature of this measurement onto a region of state space with well-defined parity by observing the collapse of a coherent state onto even or odd cat states. The measurement is fast compared with the cavity lifetime, has a high single-shot fidelity and has a 99.8 per cent probability per single measurement of leaving the parity unchanged. In combination with the deterministic encoding of quantum information in cat

  15. Assessing variability and comparing short-term biomarkers of styrene exposure using a repeated measurements approach.

    Science.gov (United States)

    Fustinoni, S; Manini, P; Campo, L; De Palma, G; Andreoli, R; Mutti, A; Bertazzi, P A; Rappaport, S M

    2010-01-15

    The aim of this work is to compare several short-term biomarkers of styrene exposure, namely urinary styrene (StyU), mercapturic acids (M1+M2), mandelic acid (MA), phenylglyoxylic acid (PGA), phenylglycine (PHG), and 4-vinylphenol conjugates (VP), for use as biomarkers of exposure in epidemiologic studies. A repeated measurements protocol (typically 4 measurements per worker over 6 weeks) was applied to measure airborne styrene (StyA) and urinary biomarkers in 10 varnish and 8 fiberglass reinforced plastic workers. Estimated geometric mean personal exposures to StyA were 2.96mg/m(3) in varnish workers and 15.7mg/m(3) in plastic workers. The corresponding levels of StyU, M1+M2, MA, PGA, MA+PGA, PHG and VP were 5.13microg/L, 0.111, 38.2, 22.7, 62.6, 0.978, and 3.97mg/g creatinine in varnish workers and 8.38microg/L, 0.303, 146, 83.4, 232, 2.85 and 3.97mg/g creatinine in plastic workers. Within-worker (sigma(wY)(2)) and between-worker (sigma(bY)(2)) variance components were estimated from the log-transformed data as were the corresponding fold ranges containing 95% of the respective lognormal distributions of daily levels ((w)R(0.95)) and subject-specific mean levels ((b)R(0.95)). Estimates of (w)R(0.95) (range: 4-26) were generally smaller than those of (b)R(0.95) (range: 5-790) for both environmental and biological markers; this indicates that exposures varied much more between workers than within workers in these groups. Since attenuation bias in an estimated exposure-response relationship increases with the variance ratio lambda=sigma(wY)(2)/sigma(bY)(2), we estimated values of lambda for all exposure measures in our study. Values of lambda were typically much less than one (median=0.220) and ranged from 0.089 for M1+M2 in plastic workers to 1.38 for PHG in varnish workers. Since values of lambda were 0.147 and 0.271 for StyA in varnish workers and plastic workers, respectively, compared to 0.178 and 0.210 for MA in the same groups, our results suggest that either

  16. Analyzing repeated measures semi-continuous data, with application to an alcohol dependence study.

    Science.gov (United States)

    Liu, Lei; Strawderman, Robert L; Johnson, Bankole A; O'Quigley, John M

    2016-02-01

    Two-part random effects models (Olsen and Schafer,(1) Tooze et al.(2)) have been applied to repeated measures of semi-continuous data, characterized by a mixture of a substantial proportion of zero values and a skewed distribution of positive values. In the original formulation of this model, the natural logarithm of the positive values is assumed to follow a normal distribution with a constant variance parameter. In this article, we review and consider three extensions of this model, allowing the positive values to follow (a) a generalized gamma distribution, (b) a log-skew-normal distribution, and (c) a normal distribution after the Box-Cox transformation. We allow for the possibility of heteroscedasticity. Maximum likelihood estimation is shown to be conveniently implemented in SAS Proc NLMIXED. The performance of the methods is compared through applications to daily drinking records in a secondary data analysis from a randomized controlled trial of topiramate for alcohol dependence treatment. We find that all three models provide a significantly better fit than the log-normal model, and there exists strong evidence for heteroscedasticity. We also compare the three models by the likelihood ratio tests for non-nested hypotheses (Vuong(3)). The results suggest that the generalized gamma distribution provides the best fit, though no statistically significant differences are found in pairwise model comparisons.

  17. Preliminary evaluation of a micro-based repeated measures testing system

    Science.gov (United States)

    Kennedy, Robert S.; Wilkes, Robert L.; Lane, Norman E.

    1985-01-01

    A need exists for an automated performance test system to study the effects of various treatments which are of interest to the aerospace medical community, i.e., the effects of drugs and environmental stress. The ethics and pragmatics of such assessment demand that repeated measures in small groups of subjects be the customary research paradigm. Test stability, reliability-efficiency and factor structure take on extreme significance; in a program of study by the U.S. Navy, 80 percent of 150 tests failed to meet minimum metric requirements. The best is being programmed on a portable microprocessor and administered along with tests in their original formats in order to examine their metric properties in the computerized mode. Twenty subjects have been tested over four replications on a 6.0 minute computerized battery (six tests) and which compared with five paper and pencil marker tests. All tests achieved stability within the four test sessions, reliability-efficiencies were high (r greater than .707 for three minutes testing), and the computerized tests were largely comparable to the paper and pencil version from which they were derived. This computerized performance test system is portable, inexpensive and rugged.

  18. A repeated measures experiment of green exercise to improve self-esteem in UK school children.

    Directory of Open Access Journals (Sweden)

    Katharine Reed

    Full Text Available Exercising in natural, green environments creates greater improvements in adult's self-esteem than exercise undertaken in urban or indoor settings. No comparable data are available for children. The aim of this study was to determine whether so called 'green exercise' affected changes in self-esteem; enjoyment and perceived exertion in children differently to urban exercise. We assessed cardiorespiratory fitness (20 m shuttle-run and self-reported physical activity (PAQ-A in 11 and 12 year olds (n = 75. Each pupil completed two 1.5 mile timed runs, one in an urban and another in a rural environment. Trials were completed one week apart during scheduled physical education lessons allocated using a repeated measures design. Self-esteem was measured before and after each trial, ratings of perceived exertion (RPE and enjoyment were assessed after completing each trial. We found a significant main effect (F (1,74, = 12.2, p<0.001, for the increase in self-esteem following exercise but there was no condition by exercise interaction (F (1,74, = 0.13, p = 0.72. There were no significant differences in perceived exertion or enjoyment between conditions. There was a negative correlation (r = -0.26, p = 0.04 between habitual physical activity and RPE during the control condition, which was not evident in the green exercise condition (r = -0.07, p = 0.55. Contrary to previous studies in adults, green exercise did not produce significantly greater increases in self-esteem than the urban exercise condition. Green exercise was enjoyed more equally by children with differing levels of habitual physical activity and has the potential to engage less active children in exercise.

  19. Repeatability and reproducibility of anterior chamber volume measurements using 3-dimensional corneal and anterior segment optical coherence tomography.

    Science.gov (United States)

    Fukuda, Shinichi; Kawana, Keisuke; Yasuno, Yoshiaki; Oshika, Tetsuro

    2011-03-01

    To evaluate the repeatability and reproducibility of anterior chamber volume (ACV) measurements using swept-source 3-dimensional corneal and anterior segment optical coherence tomography (CAS-OCT) and dual Scheimpflug imaging. Department of Ophthalmology, Institute of Clinical Medicine, University of Tsukuba, Ibaraki, Japan. Nonrandomized clinical trial. Measurements were taken in normal eyes (subject group) and in eyes with primary angle closure (PAC) (patient group). In the subject group, the entire ACV and the central 8.0 mm diameter ACV were measured using CAS-OCT and dual Scheimpflug imaging. In the patient group, the entire ACV and 8.0 mm ACV were measured using CAS-OCT. The coefficient of variation and intraclass correlation coefficient (ICC) were calculated to evaluate repeatability and reproducibility, and the correlation between the 2 devices was assessed. In the subject group, the mean 8.0 mm ACV was 110.14 mm(3) ± 12.57 (SD) using CAS-OCT and 114.51 ± 14.69 mm(3) using Scheimpflug imaging; there was a significant linear correlation (r = 0.878, P ACV on CAS-OCT was 165.15 ± 29.29 mm(3). The ICCs of the 8.0 mm and entire ACV measurements were greater than 0.94. The coefficients of repeatability and reproducibility of the 8.0 mm ACV and entire ACV measurements were less than 5%. In the patient group, the 8.0 mm and entire ACV measurements showed good reproducibility and repeatability. The CAS-OCT method allowed noninvasive measurement of the entire ACV with sufficient repeatability and reproducibility. The 8.0 mm ACV measurements with CAS-OCT and Scheimpflug imaging were comparable. Copyright © 2011 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  20. Precision (Repeatability and Reproducibility and Agreement of Corneal Power Measurements Obtained by Topcon KR-1W and iTrace.

    Directory of Open Access Journals (Sweden)

    Yanjun Hua

    Full Text Available To evaluate the repeatability and reproducibility of corneal power measurements obtained by Topcon KR-1W and iTrace, and assess the agreement with measurements obtained by Allegro Topolyzer and IOLMaster.The right eyes of 100 normal subjects were prospectively scanned 3 times using all the 4 devices. Another observer performed additional 3 consecutive scans using the Topcon KR-1W and iTrace in the same session. About one week later, the first observer repeated the measurements using the Topcon KR-1W and iTrace. The steep keratometry (Ks, flat keratometry (Kf, mean keratometry (Km, J0 and J45 were analyzed. Repeatability and reproducibility of measurements were evaluated by the within-subject standard deviation (Sw, coefficient of variation (CoV, test-retest repeatability (2.77Sw, and intraclass correlation coefficient (ICC. Agreements between devices were assessed using Bland-Altman analysis and 95% limits of agreement (LoA.Intraobserver repeatability and interobserver and intersession reproducibility of the Ks, Kf and Km showed a CoV of no more than 0.5%, a 2.77Sw of 0.70 D or less, and an ICC of no less than 0.99. However, J0 and J45 showed poor intraobserver repeatability and interobserver and intersession reproducibility (all ICCs not greater than 0.446. Statistically significant differences existed between Topcon KR-1W and IOLMaster, Topcon KR-1W and iTrace, Topcon KR-1W and Topolyzer, iTrace and Topolyzer, iTrace and IOLMaster for Ks, Kf and Km measurements (all P < 0.05. The mean differences between Topcon KR-1W, iTrace, and the other 2 devices were small. The 95% LoA were approximately 1.0 D to 1.5 D for all measurements.The Ks, Kf and Km obtained by Topcon KR-1W and iTrace showed excellent intraobserver repeatability and interobserver and intersession reproducibility in normal eyes. The agreement between Topcon KR-1W and Topolyzer, Topcon KR-1W and IOLMaster, iTrace and Topolyzer, iTrace and IOLMaster, Topcon KR-1W and iTrace were not

  1. Separating climate-induced mass transfers and instrumental effects from tectonic signal in repeated absolute gravity measurements

    Science.gov (United States)

    Van Camp, M.; Viron, O.; Avouac, J. P.

    2016-05-01

    We estimate the signature of the climate-induced mass transfers in repeated absolute gravity measurements based on satellite gravimetric measurements from the Gravity Recovery and Climate Experiment (GRACE) mission. We show results at the globe scale and compare them with repeated absolute gravity (AG) time behavior in three zones where AG surveys have been published: Northwestern Europe, Canada, and Tibet. For 10 yearly campaigns, the uncertainties affecting the determination of a linear gravity rate of change range 3-4 nm/s2/a in most cases, in the absence of instrumental artifacts. The results are consistent with what is observed for long-term repeated campaigns. We also discuss the possible artifact that can result from using short AG survey to determine the tectonic effects in a zone of high hydrological variability. We call into question the tectonic interpretation of several gravity changes reported from stations in Tibet, in particular the variation observed prior to the 2015 Gorkha earthquake.

  2. Accounting for uncertainty in volumes of seabed change measured with repeat multibeam sonar surveys

    Science.gov (United States)

    Schimel, Alexandre C. G.; Ierodiaconou, Daniel; Hulands, Lachlan; Kennedy, David M.

    2015-12-01

    Seafloors of unconsolidated sediment are highly dynamic features; eroding or accumulating under the action of tides, waves and currents. Assessing which areas of the seafloor experienced change and measuring the corresponding volumes involved provide insights into these important active sedimentation processes. Computing the difference between Digital Elevation Models (DEMs) obtained from repeat Multibeam Echosounders (MBES) surveys has become a common technique to identify these areas, but the uncertainty in these datasets considerably affects the estimation of the volumes displaced. The two main techniques used to take into account uncertainty in volume estimations are the limitation of calculations to areas experiencing a change in depth beyond a chosen threshold, and the computation of volumetric confidence intervals. However, these techniques are still in their infancy and, as a result, are often crude, seldom used or poorly understood. In this article, we explored a number of possible methodological advances to address this issue, including: (1) using the uncertainty information provided by the MBES data processing algorithm CUBE, (2) adapting fluvial geomorphology techniques for volume calculations using spatially variable thresholds and (3) volumetric histograms. The nearshore seabed off Warrnambool harbour - located in the highly energetic southwest Victorian coast, Australia - was used as a test site. Four consecutive MBES surveys were carried out over a four-months period. The difference between consecutive DEMs revealed an area near the beach experiencing large sediment transfers - mostly erosion - and an area of reef experiencing increasing deposition from the advance of a nearby sediment sheet. The volumes of sediment displaced in these two areas were calculated using the techniques described above, both traditionally and using the suggested improvements. We compared the results and discussed the applicability of the new methodological improvements

  3. Repeated Geophysical Surface Measurements to Estimate the Dynamics of Underground Coalfires

    Science.gov (United States)

    Wuttke, M. W.; Kessels, W.; Han, J.; Halisch, M.; Rüter, H.; Lindner, H.

    2009-04-01

    in a range between -130 and 176 nT. The maxima are most likely caused by the conversion of pyrite and markasit into maghemite, hematite and magnetite. Therefore the identified patches with high magnetic anomalies should have a direct connection to the burning coal in firezone 18. The firezone in Wuda has been visited now for five, that in Queergou for two times. All the discussed geophysical measurements together allow an integrated interpretation. Each result can be related to the combustion process with a particular likelihood for the vertical projection to the combustion centre. Probability calculations with chosen weight factors for each observation method are discussed. A so called fireindex deduced from the repeated measurements reveals the dynamics of the coal fire.

  4. Heart failure re-admission: measuring the ever shortening gap between repeat heart failure hospitalizations.

    Directory of Open Access Journals (Sweden)

    Jeffrey A Bakal

    Full Text Available Many quality-of-care and risk prediction metrics rely on time to first rehospitalization even though heart failure (HF patients may undergo several repeat hospitalizations. The aim of this study is to compare repeat hospitalization models. Using a population-based cohort of 40,667 patients, we examined both HF and all cause re-hospitalizations using up to five years of follow-up. Two models were examined: the gap-time model which estimates the adjusted time between hospitalizations and a multistate model which considered patients to be in one of four states; community-dwelling, in hospital for HF, in hospital for any reason, or dead. The transition probabilities and times were then modeled using patient characteristics and number of repeat hospitalizations. We found that during the five years of follow-up roughly half of the patients returned for a subsequent hospitalization for each repeat hospitalization. Additionally, we noted that the unadjusted time between hospitalizations was reduced ∼40% between each successive hospitalization. After adjustment each additional hospitalization was associated with a 28 day (95% CI: 22-35 reduction in time spent out of hospital. A similar pattern was seen when considering the four state model. A large proportion of patients had multiple repeat hospitalizations. Extending the gap between hospitalizations should be an important goal of treatment evaluation.

  5. BIS 220 Uop Material-bis220dotcom

    OpenAIRE

    greenappled

    2015-01-01

    BIS 220 Entire Course For more course tutorials visit www.bis220.com BIS 220 Week 1 Individual Assignment Information Technology Acts Paper BIS 220 Week 1 DQ 1 BIS 220 Week 1 DQ 2 BIS 220 Week 2 LT Reflection Summary BIS 220 Week 2 Individual Assignment Information Systems Proposal BIS 220 Week 2 DQ 1 BIS 220 Week 2 DQ 2 BIS 220 Week 3 Individual Assignment Types of Electronic Commerce Activity BIS 220 Week 3 LT Reflection Summary BIS 220 Week 3...

  6. Splashing Our Way to Playfulness! An Aquatic Playgroup for Young Children with Autism, A Repeated Measures Design

    Science.gov (United States)

    Fabrizi, Sarah E.

    2015-01-01

    This study investigated the effectiveness of an aquatic playgroup on the playfulness of children, ages 2 to 3 with autism spectrum disorder. Using a repeated measures design, we followed 10 children and their caregivers who participated in a 6-week aquatic playgroup in southwest Florida. Four dyads completed the entire 12-week study period. The…

  7. Splashing Our Way to Playfulness! An Aquatic Playgroup for Young Children with Autism, A Repeated Measures Design

    Science.gov (United States)

    Fabrizi, Sarah E.

    2015-01-01

    This study investigated the effectiveness of an aquatic playgroup on the playfulness of children, ages 2 to 3 with autism spectrum disorder. Using a repeated measures design, we followed 10 children and their caregivers who participated in a 6-week aquatic playgroup in southwest Florida. Four dyads completed the entire 12-week study period. The…

  8. A Correction for the Epsilon Approximate Test in Repeated Measures Designs with Two or More Independent Groups.

    Science.gov (United States)

    Lecoutre, Bruno

    1991-01-01

    The routine epsilon approximate test in repeated measures designs when the condition of circularity is unfulfilled uses an erroneous formula in the case of two or more groups. Because this may lead to underestimation of the deviation from circularity when the subject number is small, a correction is proposed. (Author/SLD)

  9. Repeatability of swept-source optical coherence tomography retinal and choroidal thickness measurements in neovascular age-related macular degeneration

    DEFF Research Database (Denmark)

    Hanumunthadu, Daren; Ilginis, Tomas; Restori, Marie

    2017-01-01

    BACKGROUND: The aim was to determine the intrasession repeatability of swept-source optical coherence tomography (SS-OCT)-derived retinal and choroidal thickness measurements in eyes with neovascular age-related macular degeneration (nAMD). METHODS: A prospective study consisting of patients with...

  10. GSTM1 and APE1 genotypes affect arsenic-induced oxidative stress: a repeated measures study

    Directory of Open Access Journals (Sweden)

    Quamruzzaman Quazi

    2007-12-01

    Full Text Available Abstract Background Chronic arsenic exposure is associated with an increased risk of skin, bladder and lung cancers. Generation of oxidative stress may contribute to arsenic carcinogenesis. Methods To investigate the association between arsenic exposure and oxidative stress, urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG was evaluated in a cohort of 97 women recruited from an arsenic-endemic region of Bangladesh in 2003. Arsenic exposure was measured in urine, toenails, and drinking water. Drinking water and urine samples were collected on three consecutive days. Susceptibility to oxidative stress was evaluated by genotyping relevant polymorphisms in glutathione-s transferase mu (GSTM1, human 8-oxoguanine glycosylase (hOGG1 and apurinic/apyrimidinic endonuclease (APE1 genes using the Taqman method. Data were analyzed using random effects Tobit regression to account for repeated measures and 8-OHdG values below the detection limit. Results A consistent negative effect for APE1 was observed across water, toenail and urinary arsenic models. APE1 148 glu/glu + asp/glu genotype was associated with a decrease in logged 8-OHdG of 0.40 (95%CI -0.73, -0.07 compared to APE1 148 asp/asp. An association between total urinary arsenic and 8-OHdG was observed among women with the GSTM1 null genotype but not in women with GSTM1 positive. Among women with GSTM1 null, a comparison of the second, third, and fourth quartiles of total urinary arsenic to the first quartile resulted in a 0.84 increase (95% CI 0.27, 1.42, a 0.98 increase (95% CI 033, 1.66 and a 0.85 increase (95% CI 0.27, 1.44 in logged 8-OHdG, respectively. No effects between 8-OHdG and toenail arsenic or drinking water arsenic were observed. Conclusion These results suggest the APE1 variant genotype decreases repair of 8-OHdG and that arsenic exposure is associated with oxidative stress in women who lack a functional GSTM1 detoxification enzyme.

  11. Pilot study: Assessing repeatability of the EcoWalk platform resistive pressure sensors to measure plantar pressure during barefoot standing

    Science.gov (United States)

    Zequera, Martha; Perdomo, Oscar; Wilches, Carlos; Vizcaya, Pedro

    2013-06-01

    Plantar pressure provides useful information to assess the feet's condition. These systems have emerged as popular tools in clinical environment. These systems present errors and no compensation information is presented by the manufacturer, leading to uncertainty in the measurements. Ten healthy subjects, 5 females and 5 males, were recruited. Lateral load distribution, antero-posterior load distribution, average pressure, contact area, and force were recorded. The aims of this study were to assess repeatability of the EcoWalk system and identify the range of pressure values observed in the normal foot. The coefficient of repeatability was less than 4% for all parameters considered.

  12. Reliability of near-infrared spectroscopy for measuring biceps brachii oxygenation during sustained and repeated isometric contractions

    Science.gov (United States)

    Muthalib, Makii; Millet, Guillaume Y.; Quaresima, Valentina; Nosaka, Kazunori

    2010-01-01

    We examine the test-retest reliability of biceps brachii tissue oxygenation index (TOI) parameters measured by near-infrared spectroscopy during a 10-s sustained and a 30-repeated (1-s contraction, 1-s relaxation) isometric contraction task at 30% of maximal voluntary contraction (30% MVC) and maximal (100% MVC) intensities. Eight healthy men (23 to 33 yr) were tested on three sessions separated by 3 h and 24 h, and the within-subject reliability of torque and each TOI parameter were determined by Bland-Altman+/-2 SD limits of agreement plots and coefficient of variation (CV). No significant (P>0.05) differences between the three sessions were found for mean values of torque and TOI parameters during the sustained and repeated tasks at both contraction intensities. All TOI parameters were within+/-2 SD limits of agreement. The CVs for torque integral were similar between the sustained and repeated task at both intensities (4 to 7%) however, the CVs for TOI parameters during the sustained and repeated task were lower for 100% MVC (7 to 11%) than for 30% MVC (22 to 36%). It is concluded that the reliability of the biceps brachii NIRS parameters during both sustained and repeated isometric contraction tasks is acceptable.

  13. Comparison of Central Corneal Thickness Measurements by Ultrasonic Pachymetry and Orbscan II Corneal Topography and Evaluation of Ultrasonic Pachymetry Repeatability

    Directory of Open Access Journals (Sweden)

    Semra Tiryaki Demir

    2014-08-01

    Full Text Available Objectives: Comparison of central corneal thickness (CCT measurements by ultrasonic pachymetry and Orbscan II corneal topography and evaluation of ultrasonic pachymetry repeatability for same observer. Materials and Methods: The study included 132, 82, and 80 eyes of 66 patients with primary open-angle glaucoma (POAG, 41 patients with ocular hypertension (OHT, and 40 controls, respectively. All subjects were subjected to routine ophthalmic examination. Orbscan II (Bausch&Lomb corneal topography and ultrasonic pachymetry (Nidek Ultrasonic Pachymetry UP-1000 were used for measurement of CCT. ANOVA (Turkey test was used for variable distribution, paired sample t-test was used for repeated measurements, and the analyses were done by SPSS 20.0. Results: Mean CCT was 558.9±37.2 µm by ultrasonic pachymetry and 553.4±37 µm by corneal topography. There was a significant difference between the two measurements (p0.05. CCT was 555±39.2 µm, 564.3±28.4 µm, and 559.7±41.5 µm by ultrasonic pachymetry in POAG, OHT, and control subjects, respectively; CCT was 550.3±38.3 µm, 558.5±28 µm, and 553.2±42.5 µm by Orbscan II corneal topography in POAG, OHT, and control subjects, respectively. There was a significant linear correlation between Orbscan II corneal topography and ultrasonic pachymetry in CCT measurements (r=0.975, p<0.0001. Repeatability of ultrasonic pachymetry for same observer was (ICC value 0.990. Conclusion: There is a significant correlation between Orbscan II corneal topography and ultrasonic pachymetry in CCT measurements. These two methods of measurements should not be substituted for each other, since ultrasonic pachymetry measures CCT greater than Orbscan II corneal topography. Repeatability of ultrasonic pachymetry for same observer is very high. (Turk J Ophthalmol 2014; 44: 263-7

  14. CLEOPATRA 11.05 to 31.07.1992: Synopsis of measurements and results; CLEOPATRA 11.05 bis 31.07.1992: Synopse der Messungen und Ergebnisuebersicht

    Energy Technology Data Exchange (ETDEWEB)

    Meischner, P.

    1993-12-31

    The field program CLEOPATRA (Cloud Experiment Oberpfaffenhofen and Transports) was performed in Southern Germany 50 km north of the Alpine foothills, an area of known enhanced thunderstorm activity. The general goal was to quantify elements of the hydrological cycle on a regional scale in dependence upon precipitation events and the vegetation state. Embedded goals are to describe the mechanisms that force organizations of deep convective systems, to compare theories and observations of atmospheric depositions, and to test and compare observational methods from ground, aircraft, and space. The observational setup, including 10 research aircraft, four radar systems, and different ground-based networks, was operational from 11 May until 31 July 1992 to cover an essential period of the growing season. The results of measurements are compiled in this documentation including a calender of observations performed. (orig.). 72 figs., 6 tabs. [Deutsch] Das Feldexperiment CLEOPATRA (Cloud Experiment Oberpfaffenhofen and Transports) diente der Untersuchung von Austauschprozessen zwischen Boden, Vegetation und Atmosphaere, von Wolkensystemen und Niederschlagsentstehung, von Umwandlungsprozessen und Auswaschvorgaengen fuer Luftbeimengungen, der Weiterentwicklung und Validierung entsprechender Fernerkundungsmethoden, sowie der Quantifizierung des Einflusses von Wolken und Niederschlag auf Kommunikationsverbindungen Erde-Satellit. Aufgrund der wissenschaftlichen Zielsetzungen sind die Messkonzepte, Messungen am Boden und eine Reihe von Flugzeugmissionen festgelegt worden, die je nach Wetterlage und den zur Verfuegung stehenden Messsystemen vorgeplant waren. Innerhalb des gesamten Messzeitraumes vom 11. Mai bis 31. Juli 1992 gabe es zwei Intensivmessphasen, eine vom 18. Mai bis 06. Juni und eine vom 13. Juli bis 31. Juli. Dieser Band gibt einen Ueberblick ueber die tatsaechlich zum Einsatz gekommenen Messsysteme, die durchgefuehrten Missionen und die gewonnenen Daten. (orig.)

  15. Repeatability of Volume and Regional Body Composition Measurements of the Lower Limb Using Dual-energy X-ray Absorptiometry

    DEFF Research Database (Denmark)

    Gjorup, Caroline A; Zerahn, Bo; Juul, Sarah

    2016-01-01

    Lower limb lymphedema is a dynamic condition in which tissue composition and volume measurements are affected. Various definitions of lower limb lymphedema exist but volume differences between the limbs are widely used. It is therefore necessary to have a readily available noninvasive measurement...... of agreement on the Bland-Altman plots. These results confirm DXA to be a highly repeatable method for volume and tissue composition measurements of the lower limb. In a population at risk of lymphedema, DXA offers a clinically readily available noninvasive method allowing multiple measurements of volume...... and tissue composition on a routine basis, important for diagnosing, monitoring, managing, and researching lymphedema....

  16. Power analysis for multivariate and repeated measurements designs via SPSS: correction and extension of D'Amico, Neilands, and Zambarano (2001).

    Science.gov (United States)

    Osborne, Jason W

    2006-05-01

    D'Amico, Neilands, and Zambarano (2001) published SPSS syntax to perform power analyses for three complex procedures: ANCOVA, MANOVA, and repeated measures ANOVA. Unfortunately, the published SPSS syntax for performing the repeated measures analysis needed some minor revision in order to perform the analysis correctly. This article presents the corrected syntax that will successfully perform the repeated measures analysis and provides some guidance on modifying the syntax to customize the analysis.

  17. Repeatability and reproducibility of measurements of the suburethral tape location obtained in pelvic floor ultrasound performed with a transvaginal probe

    Directory of Open Access Journals (Sweden)

    Maria Magdalena Dresler

    2017-06-01

    Full Text Available Introduction: Implants used to treat patients with urogynecological conditions are well visible in US examination. The position of the suburethral tape (sling is determined in relation to the urethra or the pubic symphysis. Aim of the study: The study was aimed at assessing the accuracy of measurements determining suburethral tape location obtained in pelvic US examination performed with a transvaginal probe. Material and methods: The analysis covered the results of sonographic measurements obtained according to a standardized technique in women referred for urogynecological diagnostics. Data from a total of 68 patients were used to analyse the repeatability and reproducibility of results obtained on the same day. Results: The intraclass correlation coefficient for the repeatability and reproducibility of the sonographic measurements of suburethral tape location obtained with a transvaginal probe ranged from 0.6665 to 0.9911. The analysis of the measurements confirmed their consistency to be excellent or good. Conclusions: Excellent and good repeatability and reproducibility of the measurements of the suburethral tape location obtained in a pelvic ultrasound performed with a transvaginal probe confirm the test’s validity and usefulness for clinical and academic purposes.

  18. Repeatability of swept-source optical coherence tomography retinal and choroidal thickness measurements in neovascular age-related macular degeneration.

    Science.gov (United States)

    Hanumunthadu, Daren; Ilginis, Tomas; Restori, Marie; Sagoo, Mandeep S; Tufail, Adnan; Balaggan, Kamaljit S; Patel, Praveen J

    2017-05-01

    The aim was to determine the intrasession repeatability of swept-source optical coherence tomography (SS-OCT)-derived retinal and choroidal thickness measurements in eyes with neovascular age-related macular degeneration (nAMD). A prospective study consisting of patients with active nAMD enrolled in the Distance of Choroid Study at Moorfields Eye Hospital, London. Patients underwent three 12×9 mm macular raster scans using the deep range imaging (DRI) OCT-1 SS-OCT (Topcon) device in a single imaging session. Retinal and choroidal thicknesses were calculated for the ETDRS macular subfields. Repeatability was calculated according to methods described by Bland and Altman. 39 eyes of 39 patients with nAMD were included with a mean (±SD) age of 73.9 (±7.2) years. The mean (±SD) retinal thickness of the central macular subfield was 225.7 μm (±12.4 μm). The repeatability this subfield, expressed as a percentage of the mean central macular subfield thickness, was 23.2%. The percentage repeatability of the other macular subfields ranged from 13.2% to 28.7%. The intrasession coefficient of repeatability of choroidal thickness of the central macular subfield was 57.2 μm with a mean choroidal thickness (±SD) of 181 μm (±15.8 μm). This study suggests that a change >23.2% of retinal thickness and 57.2 μm choroidal thickness in the central macular subfield is required to distinguish true clinical change from measurement variability when using the DRI OCT-1 device to manage patients with nAMD. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  19. Comparison of Central Corneal Thickness Measurements by Ultrasonic Pachymetry and Orbscan II Corneal Topography and Evaluation of Ultrasonic Pachymetry Repeatability

    OpenAIRE

    Semra Tiryaki Demir; Mahmut Odabaşı; Mehmet Ersin Oba; Ayşe Burcu Dirim; Efe Can; Orhan Kara

    2014-01-01

    Objectives: Comparison of central corneal thickness (CCT) measurements by ultrasonic pachymetry and Orbscan II corneal topography and evaluation of ultrasonic pachymetry repeatability for same observer. Materials and Methods: The study included 132, 82, and 80 eyes of 66 patients with primary open-angle glaucoma (POAG), 41 patients with ocular hypertension (OHT), and 40 controls, respectively. All subjects were subjected to routine ophthalmic examination. Orbscan II (Bausch&Lomb) ...

  20. Comparison of Repeated Measurement Design and Mixed Models in Evaluation of the Entonox Effect on Labor Pain

    Directory of Open Access Journals (Sweden)

    Nasim Karimi

    2017-01-01

    Full Text Available Background & objectives: In many medical studies, the response variable is measured repeatedly over time to evaluate the treatment effect that is known as longitudinal study. The analysis method for this type of data is repeated measures ANOVA that uses only one correlation structure and the results are not valid with inappropriate correlation structure. To avoid this problem, a convenient alternative is mixed models. So, the aim of this study was to compare of mixed and repeated measurement models for examination of the Entonox effect on the labor pain. Methods: This experimental study was designed to compare the effect of Entonox and oxygen inhalation on pain relief between two groups. Data were analyzed using repeated measurement and mixed models with different correlation structures. Selection and comparison of proper correlation structures performed using Akaike information criterion, Bayesian information criterion and restricted log-likelihood. Data were analyzed using SPSS-22. Results: Results of our study showed that all variables containing analgesia methods, labor duration of the first and second stages, and time were significant in these tests. In mixed model, heterogeneous first-order autoregressive, first-order autoregressive, heterogeneous Toeplitz and unstructured correlation structures were recognized as the best structures. Also, all variables were significant in these structures. Unstructured variance covariance matrix was recognized as the worst structure and labor duration of the first and second stages was not significant in this structure. Conclusions: This study showed that the Entonox inhalation has a significant effect on pain relief in primiparous and it is confirmed by all of the models.

  1. Incomplete quality of life data in lung transplant research: comparing cross sectional, repeated measures ANOVA, and multi-level analysis

    Directory of Open Access Journals (Sweden)

    van der Bij Wim

    2005-09-01

    Full Text Available Abstract Background In longitudinal studies on Health Related Quality of Life (HRQL it frequently occurs that patients have one or more missing forms, which may cause bias, and reduce the sample size. Aims of the present study were to address the problem of missing data in the field of lung transplantation (LgTX and HRQL, to compare results obtained with different methods of analysis, and to show the value of each type of statistical method used to summarize data. Methods Results from cross-sectional analysis, repeated measures on complete cases (ANOVA, and a multi-level analysis were compared. The scores on the dimension 'energy' of the Nottingham Health Profile (NHP after transplantation were used to illustrate the differences between methods. Results Compared to repeated measures ANOVA, the cross-sectional and multi-level analysis included more patients, and allowed for a longer period of follow-up. In contrast to the cross sectional analyses, in the complete case analysis, and the multi-level analysis, the correlation between different time points was taken into account. Patterns over time of the three methods were comparable. In general, results from repeated measures ANOVA showed the most favorable energy scores, and results from the multi-level analysis the least favorable. Due to the separate subgroups per time point in the cross-sectional analysis, and the relatively small number of patients in the repeated measures ANOVA, inclusion of predictors was only possible in the multi-level analysis. Conclusion Results obtained with the various methods of analysis differed, indicating some reduction of bias took place. Multi-level analysis is a useful approach to study changes over time in a data set where missing data, to reduce bias, make efficient use of available data, and to include predictors, in studies concerning the effects of LgTX on HRQL.

  2. Repeated Microsphere Delivery for Serial Measurement of Regional Blood Perfusion in the Chronically Instrumented, Conscious Canine

    Science.gov (United States)

    Bartoli, Carlo R.; Okabe, Kazunori; Akiyama, Ichiro; Coull, Brent; Godleski, John J.

    2008-01-01

    INTRODUCTION For chronic, repeated hemodynamic studies in conscious dogs, we designed and tested a chronically instrumented canine, microsphere delivery model. The goals of this study were to investigate the accuracy of repeated estimations of blood perfusion using fluorescent-labeled microspheres and to develop and validate a chronic preparation that permits consecutive estimations in the same conscious animal over an extended protocol. METHODS Via thoracotomy, 9 dogs were instrumented with left atrial appendage and aortic vascular access catheters connected to subcutaneous vascular access ports (VAPs). Four animals received 7 serial injections of 1.6 million 15μm microspheres (total: 11.2 million), and five animals received 8 serial injections of 2.25 million microspheres (total: 18 million) over the course of 11 or 18 weeks. RESULTS All catheters have remained bidirectionally patent during protocol for 14.9±0.8 (Mean±SEM) weeks. Sphere accumulation did not significantly alter global myocardial (p=0.69, p=0.25), renal (p=0.92, p=0.12), hepatic (p=0.84, p=0.32), or splenic (p=0.33, p=0.70) blood perfusion in either set of animals. CONCLUSIONS Catheters remained bidirectionally patent for months, did not interfere with the hemodynamic responses of the preparation, and allowed repeat percutaneous injection of microspheres and withdrawal of reference arterial blood from within conscious canines. Eight serial injections totaling 18 million microspheres over 18 weeks did not alter regional myocardial, hepatic, renal, or splenic blood flow. This dependable, chronic, percutaneous arterial access preparation provides a means for examining acute and long-term effects of pathophysiological, pharmaceutical, and environmental influences on regional arterial blood perfusion in conscious, large animals. PMID:17632127

  3. Measuring Aseismic Slip through Characteristically Repeating Earthquakes at the Mendocino Triple Junction, Northern California

    Science.gov (United States)

    Materna, K.; Taira, T.; Burgmann, R.

    2016-12-01

    The Mendocino Triple Junction (MTJ), at the transition point between the San Andreas fault system, the Mendocino Transform Fault, and the Cascadia Subduction Zone, undergoes rapid tectonic deformation and produces more large (M>6.0) earthquakes than any region in California. Most of the active faults of the triple junction are located offshore, making it difficult to characterize both seismic slip and aseismic creep. In this work, we study aseismic creep rates near the MTJ using characteristically repeating earthquakes (CREs) as indicators of creep rate. CREs are generally interpreted as repeated failures of the same seismic patch within an otherwise creeping fault zone; as a consequence, the magnitude and recurrence time of the CREs can be used to determine a fault's creep rate through empirically calibrated scaling relations. Using seismic data from 2010-2016, we identify CREs as recorded by an array of eight 100-Hz PBO borehole seismometers deployed in the Cape Mendocino area. For each event pair with epicenters less than 30 km apart, we compute the cross-spectral coherence of 20 seconds of data starting one second before the P-wave arrival. We then select pairs with high coherence in an appropriate frequency band, which is determined uniquely for each event pair based on event magnitude, station distance, and signal-to-noise ratio. The most similar events (with median coherence above 0.95 at two or more stations) are selected as CREs and then grouped into CRE families, and each family is used to infer a local creep rate. On the Mendocino Transform Fault, we find relatively high creep rates of >5 cm/year that increase closer to the Gorda Ridge. Closer to shore and to the MTJ itself, we find many families of repeaters on and off the transform fault with highly variable creep rates, indicative of the complex deformation that takes place there.

  4. Persistent repeated measurements by magnetic resonance spectroscopy demonstrate minimal hepatic encephalopathy: a case report.

    Science.gov (United States)

    Scheau, C; Popa, G A; Ghergus, A E; Preda, E M; Capsa, R A; Lupescu, I G

    2013-09-15

    Minimal Hepatic Encephalopathy (MHE), previously referred to as infraclinical or subclinical is a precursor in the development of clinical hepatic encephalopathy (HE). The demonstration of MHE is done through neuropsychological testing in the absence of clinical evidence of HE, patients showing only a mild cognitive impairment. Neuropsychological tests employed consist of Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) and portosystemic encephalopathy (PSE) test score. Unfortunately, there are numerous occasions when the tests prove irrelevant: in the situation of inexperienced investigators, the patient's poor education, vision problems or concurring central nervous system disease, all of which may delay or deviate from the correct diagnosis.

  5. Accuracy and repeatability of direct ciliary sulcus diameter measurements by full-scale 50-megahertz ultrasound biomicroscopy

    Institute of Scientific and Technical Information of China (English)

    LI De-jiao; WANG Ning-li; CHEN Shu; LI Shu-ning; MU Da-peng; WANG Tao

    2009-01-01

    Background Phakic intraocular lens (pIOL) implantation has been a popular means for the treatment of high ametropia. Measurements of ciliary sulcus diameter is important for pIOL size determining. But till now, no perfect system can directly measure it. The present study was to evaluate the accuracy, repeatability and reproducibility of direct sulcus diameter measurements obtained by a full-scale 50-megahertz (MHz) ultrasound biomicroscopy (UBM).Methods A fresh cadaver human eye with a scale marker inserted through the posterior chamber plane from 3 o'clock to 9 o'clock meridian and 30 randomly selected eyes from 30 normal subjects were scanned by full-scale 50-MHz UBM in horizontal meridional scan plane. The distance between the scales and the whole length of the marker inside the cadaver eye were measured by the same observer using the "built-in" measurement tools and the indicating error of instrument was calculated. Reproducibility of the measurement was evaluated in 30 eyes by 2 operators using Blander and Altman plot test. Repeatability was evaluated from 10 successive eyes randomly selected from the 30 eyes by one operator.Results On a scale of 1 mm, the greatest indicating error was 40 μm; the mean largest indicating error of 1 mm scale from the 10 images was (26±14) μm; on a scale of 11 mm, the greatest indicating error was 70 μo; the error rate was 0.64%. The mean length of the needle inside the eye of the 10 images was 11.05 mm, with the mean indicating error of 47 μm, the average error rate was 0.43%. For ciliary sulcus diameter measurements in vivo, the coefficient of variation was 0.38%; the coefficients of repeatability for intra-observer and inter-observer measurements were 1.99% and 2.55%, respectively. The limits of agreement for intra-observer and inter-observer measurement were-0.41 mm to 0.48 mm and -0.59 mm to 0.58 ram, respectively.Conclusion The full-scale 50-MHz UBM can be a high accuracy and good repeatability means for direct

  6. Chemical kinetic measurements of the effect of trans- and cis-3,3'-Bis[(trimethylammonio)methyl]azobenzene bromide on acetylcholine receptor mediated ion translocation in Electrophorus electricus and Torpedo californica.

    Science.gov (United States)

    Delcour, A H; Hess, G P

    1986-04-08

    A quench-flow technique was used to study the effect of trans- and cis-3,3'-bis[(trimethylammonio)methyl]azobenzene bromide (trans- and cis-Bis-Q), photoisomerizable ligands, on the acetylcholine receptor in vesicles prepared from the electric organ of Electrophorus electricus and of Torpedo californica. In E. electricus, two rate coefficients of the receptor-mediated translocation of 86Rb+ induced with trans-Bis-Q were measured: JA, the rate coefficient for ion flux, and alpha, the rate coefficient for receptor inactivation (desensitization). Both rate coefficients increase with increasing concentrations of Bis-Q up to 50 microM. At higher concentrations JA decreases in a concentration-dependent manner while alpha remains unchanged. This effect was previously observed with suberyldicholine [Pasquale, E. B., Takeyasu, K., Udgaonkar, J., Cash, D.J., Severski, M.C., & Hess, G. P. (1983) Biochemistry 22, 5967-5973] and with acetylcholine [Takeyasu, K., Udgaonkar, J., & Hess, G. P. (1983) Biochemistry 22, 5973-5978] and was analyzed in terms of a minimum mechanism that accounts for the properties of activation, desensitization, and inhibition of the receptor. Two molecules of trans-Bis-Q must be bound for the channel to open, but at concentrations greater than 50 microM the population of open channels decreases because of the additional binding of one molecule of trans-Bis-Q to a regulatory inhibitory site, independent of the activating sites. cis-Bis-Q does not induce transmembrane ion flux, but it does inhibit the response of the receptor to acetylcholine and induces inactivation (desensitization) in the micromolar range.(ABSTRACT TRUNCATED AT 250 WORDS)

  7. Measurement repeatability of tibial tuberosity-trochlear groove offset distance in red fox (Vulpes vulpes) cadavers

    DEFF Research Database (Denmark)

    Miles, James Edward; Jensen, Bente Rona; Kirpensteijn, Jolle

    2013-01-01

    Objective-To describe CT image reconstruction criteria for measurement of the tibial tuberosity-trochlear groove (TT-TG) offset distance, evaluate intra- and inter-reconstruction repeatability, and identify key sources of error in the measurement technique, as determined in vulpine hind limbs. An...... and applied criteria. The TT-TG offset distance has potential as an objective assessment of alignment of the distal portion of the quadriceps mechanism; its use as an aid in case selection for corrective femoral osteotomy among dogs with medial patellar luxation warrants investigation....

  8. BiSpectral Index (BIS monitoring may detect critical hypotension before automated non-invasive blood pressure (NIBP measurement during general anaesthesia; a case report. [v1; ref status: indexed, http://f1000r.es/2oi

    Directory of Open Access Journals (Sweden)

    Matthew M. J. Smith

    2014-01-01

    Full Text Available A patient undergoing general anaesthesia for neurosurgery exhibited an unexpected sudden decrease in the BiSpectral Index (BIS value to near-zero. This prompted the detection of profound hypotension using non-invasive blood pressure (NIBP measurement and expedited urgent assessment and treatment, with the patient making a full recovery. Widely regarded as a ‘depth of anaesthesia’ monitor, this case demonstrates the potential extra clinical benefit BIS may have in the detection of critical incidents such as anaphylaxis during general anaesthesia.

  9. Intergenic and repeat transcription in human, chimpanzee and macaque brains measured by RNA-Seq.

    Directory of Open Access Journals (Sweden)

    Augix Guohua Xu

    Full Text Available Transcription is the first step connecting genetic information with an organism's phenotype. While expression of annotated genes in the human brain has been characterized extensively, our knowledge about the scope and the conservation of transcripts located outside of the known genes' boundaries is limited. Here, we use high-throughput transcriptome sequencing (RNA-Seq to characterize the total non-ribosomal transcriptome of human, chimpanzee, and rhesus macaque brain. In all species, only 20-28% of non-ribosomal transcripts correspond to annotated exons and 20-23% to introns. By contrast, transcripts originating within intronic and intergenic repetitive sequences constitute 40-48% of the total brain transcriptome. Notably, some repeat families show elevated transcription. In non-repetitive intergenic regions, we identify and characterize 1,093 distinct regions highly expressed in the human brain. These regions are conserved at the RNA expression level across primates studied and at the DNA sequence level across mammals. A large proportion of these transcripts (20% represents 3'UTR extensions of known genes and may play roles in alternative microRNA-directed regulation. Finally, we show that while transcriptome divergence between species increases with evolutionary time, intergenic transcripts show more expression differences among species and exons show less. Our results show that many yet uncharacterized evolutionary conserved transcripts exist in the human brain. Some of these transcripts may play roles in transcriptional regulation and contribute to evolution of human-specific phenotypic traits.

  10. A Description of Quasar Variability Measured Using Repeated SDSS and POSS Imaging

    CERN Document Server

    MacLeod, Chelsea L; Sesar, Branimir; de Vries, Wim; Kochanek, Christopher S; Kelly, Brandon C; Becker, Andrew C; Lupton, Robert H; Hall, Patrick B; Richards, Gordon T; Anderson, Scott F; Schneider, Donald P

    2011-01-01

    We provide a quantitative description and statistical interpretation of the optical continuum variability of quasars. The Sloan Digital Sky Survey (SDSS) has obtained repeated imaging in five UV-to-IR photometric bands for 34,727 spectroscopically confirmed quasars. About 10,000 quasars have an average of 60 observations in each band obtained over a decade along stripe 82 (S82), whereas the remaining ~25,000 have 2-3 observations due to scan overlaps. The observed time lags span the range from a day to almost 10 years, and constrain quasar variability at rest-frame time lags of up to 4 years, and at rest-frame wavelengths from 1000A to 6000A. We publicly release a user-friendly catalog of quasars from the SDSS Data Release 7 that have been observed at least twice in SDSS or once in both SDSS and the Palomar Observatory Sky Survey, and we use it to analyze the ensemble properties of quasar variability. Based on a damped random walk (DRW) model defined by a characteristic time scale and an asymptotic variabilit...

  11. Estimation of spatial patterns of urban air pollution over a 4-week period from repeated 5-min measurements

    Science.gov (United States)

    Gillespie, Jonathan; Masey, Nicola; Heal, Mathew R.; Hamilton, Scott; Beverland, Iain J.

    2017-02-01

    Determination of intra-urban spatial variations in air pollutant concentrations for exposure assessment requires substantial time and monitoring equipment. The objective of this study was to establish if short-duration measurements of air pollutants can be used to estimate longer-term pollutant concentrations. We compared 5-min measurements of black carbon (BC) and particle number (PN) concentrations made once per week on 5 occasions, with 4 consecutive 1-week average nitrogen dioxide (NO2) concentrations at 18 locations at a range of distances from busy roads in Glasgow, UK. 5-min BC and PN measurements (averaged over the two 5-min periods at the start and end of a week) explained 40-80%, and 7-64% respectively, of spatial variation in the intervening 1-week NO2 concentrations for individual weeks. Adjustment for variations in background concentrations increased the percentage of explained variation in the bivariate relationship between the full set of NO2 and BC measurements over the 4-week period from 28% to 50% prior to averaging of repeat measurements. The averages of five 5-min BC and PN measurements made over 5 weeks explained 75% and 33% respectively of the variation in average 1-week NO2 concentrations over the same period. The relatively high explained variation observed between BC and NO2 measured on different time scales suggests that, with appropriate steps to correct or average out temporal variations, repeated short-term measurements can be used to provide useful information on longer-term spatial patterns for these traffic-related pollutants.

  12. Variation in repeated mouth-opening measurements in head and neck cancer patients with and without trismus.

    Science.gov (United States)

    Jager-Wittenaar, H; Dijkstra, P U; Vissink, A; van Oort, R P; Roodenburg, J L N

    2009-01-01

    Trismus after head and neck cancer treatment may severely limit mandibular functioning. Interventions aimed at reducing trismus can only be evaluated when the amount of variation associated with these measurements is known. The aim of this study was to analyse the variation in mouth-opening measurements in patients treated for head and neck cancer, with and without trismus. Maximal mouth opening was measured in 120 patients in two sessions of three repeated measurements by one observer. To analyse the influence of interobserver variation on mouth-opening measurements a subgroup of 30 patients was measured by a second observer. The standard deviation of the six measurements per patient was used as the variation in measurements of maximal mouth opening. No significant difference was found in maximal mouth opening in patients with (n=33) or without (n=87) trismus. The interobserver intraclass correlation coefficient (ICC) was 0.98. Intraobserver ICC and intersession ICC reliabilities both were 0.99. The variation in the mean values of the three measurements was only slightly smaller than the variation of the single measurements. Variation in maximal mouth opening in patients with trismus does not differ from variation in maximal mouth opening in patients without trismus. Interobserver variation is limited.

  13. The use of a measure of acute irritation to predict the outcome of repeated usage of hand soap products.

    Science.gov (United States)

    Williams, C; Wilkinson, M; McShane, P; Pennington, D; Fernandez, C; Pierce, S

    2011-06-01

    Healthcare-associated infection is an important worldwide problem that could be reduced by better hand hygiene practice. However, an increasing number of healthcare workers are experiencing irritant contact dermatitis of the hands as a result of repeated hand washing. This may lead to a reduced level of compliance with regard to hand hygiene. To assess whether a measure of acute irritation by hand soaps could predict the effects of repeated usage over a 2-week period. In a double-blind, randomized comparison study, the comparative irritation potential of four different hand soaps was assessed over a 24-h treatment period. The effect of repeated hand washing with the hand soap products over a 2-week period in healthy adult volunteers on skin barrier function was then determined by assessment of transepidermal water loss (TEWL), epidermal hydration and a visual assessment using the Hand Eczema Severity Index (HECSI) at days 0, 7 and 14. A total of 121 subjects from the 123 recruited completed phase 1 of the study. All four products were seen to be significantly different from each other in terms of the irritant reaction observed and all products resulted in a significantly higher irritation compared with the no-treatment control. Seventy-nine of the initial 121 subjects were then enrolled into the repeated usage study. A statistically significant worsening of the clinical condition of the skin as measured by HECSI was seen from baseline to day 14 in those subjects repeatedly washing their hands with two of the four soap products (products C and D) with P-values of 0·02 and 0·01, respectively. Subclinical assessment of the skin barrier function by measuring epidermal hydration was significantly increased from baseline to day 7 after repeated hand washing with products A, B and D but overall no significant change was seen in all four products tested by day 14. A statistically significant increase in TEWL at day 14 was seen for product A (P = 0·02) indicating a

  14. A DESCRIPTION OF QUASAR VARIABILITY MEASURED USING REPEATED SDSS AND POSS IMAGING

    Energy Technology Data Exchange (ETDEWEB)

    MacLeod, Chelsea L.; Ivezic, Zeljko; Becker, Andrew C.; Anderson, Scott F. [Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195 (United States); Sesar, Branimir [Division of Physics, Mathematics and Astronomy, California Institute of Technology, Pasadena, CA 91125 (United States); De Vries, Wim [Department of Physics, University of California, One Shields Ave, Davis, CA 95616 (United States); Kochanek, Christopher S. [Department of Astronomy, Ohio State University, 140 West 18th Avenue, Columbus, OH 43210 (United States); Kelly, Brandon C. [Department of Physics, University of California, Santa Barbara, CA 93106 (United States); Lupton, Robert H. [Department of Astrophysical Sciences, Princeton University, Princeton, New Jersey 08544 (United States); Hall, Patrick B. [Department of Physics and Astronomy, York University, Toronto, ON M3J 1P3 (Canada); Richards, Gordon T. [Department of Physics, Drexel University, 3141 Chestnut Street, Philadelphia, PA 19104 (United States); Schneider, Donald P. [Department of Astronomy and Astrophysics, Pennsylvania State University, 525 Davey Laboratory, University Park, PA 16802 (United States)

    2012-07-10

    We provide a quantitative description and statistical interpretation of the optical continuum variability of quasars. The Sloan Digital Sky Survey (SDSS) has obtained repeated imaging in five UV-to-IR photometric bands for 33,881 spectroscopically confirmed quasars. About 10,000 quasars have an average of 60 observations in each band obtained over a decade along Stripe 82 (S82), whereas the remaining {approx}25,000 have 2-3 observations due to scan overlaps. The observed time lags span the range from a day to almost 10 years, and constrain quasar variability at rest-frame time lags of up to 4 years, and at rest-frame wavelengths from 1000 A to 6000 A. We publicly release a user-friendly catalog of quasars from the SDSS Data Release 7 that have been observed at least twice in SDSS or once in both SDSS and the Palomar Observatory Sky Survey, and we use it to analyze the ensemble properties of quasar variability. Based on a damped random walk (DRW) model defined by a characteristic timescale and an asymptotic variability amplitude that scale with the luminosity, black hole mass, and rest wavelength for individual quasars calibrated in S82, we can fully explain the ensemble variability statistics of the non-S82 quasars such as the exponential distribution of large magnitude changes. All available data are consistent with the DRW model as a viable description of the optical continuum variability of quasars on timescales of {approx}5-2000 days in the rest frame. We use these models to predict the incidence of quasar contamination in transient surveys such as those from the Palomar Transient Factory and Large Synoptic Survey Telescope.

  15. Repeatability of Cone Spacing Measures in Eyes With Inherited Retinal Degenerations

    National Research Council Canada - National Science Library

    Zayit-Soudry, Shiri; Sippl-Swezey, Nicolas; Porco, Travis C; Lynch, Stephanie K; Syed, Reema; Ratnam, Kavitha; Menghini, Moreno; Roorda, Austin J; Duncan, Jacque L

    2015-01-01

    ...)-derived cone spacing measures in eyes with inherited retinal degenerations (IRD) and in normal eyes. Twenty IRD patients and 10 visually normal subjects underwent AOSLO imaging at two visits separated by no more than 1 month...

  16. Repeatability of Choroidal Thickness Measurements on Enhanced Depth Imaging Optical Coherence Tomography Using Different Posterior Boundaries.

    Science.gov (United States)

    Vuong, Vivian S; Moisseiev, Elad; Cunefare, David; Farsiu, Sina; Moshiri, Ala; Yiu, Glenn

    2016-09-01

    To assess the reliability of manual choroidal thickness measurements by comparing different posterior boundary definitions of the choroidal-scleral junction on enhanced depth imaging optical coherence tomography (EDI-OCT). Reliability analysis. Two graders marked the choroidal-scleral junction with segmentation software using different posterior boundaries: (1) the outer border of the choroidal vessel lumen, (2) the outer border of the choroid stroma, and (3) the inner border of the sclera, to measure the vascular choroidal thickness (VCT), stromal choroidal thickness (SCT), and total choroidal thickness (TCT), respectively. Measurements were taken at 0.5-mm intervals from 1.5 mm nasal to 1.5 mm temporal to the fovea, and averaged continuously across the central 3 mm of the macula. Intraclass correlation coefficient (ICC) and coefficient of reliability (CR) were compared to assess intergrader and intragrader reliability. Choroidal thickness measurements varied significantly with different posterior boundaries (P choroidal-scleral junction visibility was Choroidal thickness measurements are more reproducible when measured to the border of the choroid stroma (SCT) than the vascular lumen (VCT) or sclera (TCT). Copyright © 2016 Elsevier Inc. All rights reserved.

  17. The Repeatability Assessment of Three-Dimensional Capsule-Intraocular Lens Complex Measurements by Means of High-Speed Swept-Source Optical Coherence Tomography

    Science.gov (United States)

    Chang, Pingjun; Li, Jin; Savini, Giacomo; Huang, Jinhai; Huang, Shenghai; Zhao, Yinying; Liao, Na; Lin, Lei; Yu, Xiaoyu; Zhao, Yun-e

    2015-01-01

    Purpose To rebuild the three-dimensional (3-D) model of the anterior segment by high-speed swept-source optical coherence tomography (SSOCT) and evaluate the repeatability of measurement for the parameters of capsule-intraocular lens (C-IOL) complex. Methods Twenty-two pseudophakic eyes from 22 patients were enrolled. Three continuous SSOCT measurements were performed in all eyes and the tomograms obtained were used for 3-D reconstruction. The output data were used to evaluate the measurement repeatability. The parameters included postoperative aqueous depth (PAD), the area and diameter of the anterior capsule opening (Area and D), IOL tilt (IOL-T), horizontal, vertical, and space decentration of the IOL, anterior capsule opening, and IOL-anterior capsule opening. Results PAD, IOL-T, Area, D, and all decentration measurements showed high repeatability. Repeated measure analysis showed there was no statistically significant difference among the three continuous measurements (all P > .05). Pearson correlation analysis showed high correlation between each pair of them (all r >0.90, P<0.001). ICCs were all more than 0.9 for all parameters. The 95% LoAs of all parameters were narrow for comparison of three measurements, which showed high repeatability for three measurements. Conclusion SSOCT is available to be a new method for the 3-D measurement of C-IOL complex after cataract surgery. This method presented high repeatability in measuring the parameters of the C-IOL complex. PMID:26600254

  18. Repeatability of measurements: Non-Hermitian observables and quantum Coriolis force

    Science.gov (United States)

    Gardas, Bartłomiej; Deffner, Sebastian; Saxena, Avadh

    2016-08-01

    A noncommuting measurement transfers, via the apparatus, information encoded in a system's state to the external "observer." Classical measurements determine properties of physical objects. In the quantum realm, the very same notion restricts the recording process to orthogonal states as only those are distinguishable by measurements. Therefore, even a possibility to describe physical reality by means of non-Hermitian operators should volens nolens be excluded as their eigenstates are not orthogonal. Here, we show that non-Hermitian operators with real spectra can be treated within the standard framework of quantum mechanics. Furthermore, we propose a quantum canonical transformation that maps Hermitian systems onto non-Hermitian ones. Similar to classical inertial forces this map is accompanied by an energetic cost, pinning the system on the unitary path.

  19. Mediation of the Relationship between Maternal Phthalate Exposure and Preterm Birth by Oxidative Stress with Repeated Measurements across Pregnancy.

    Science.gov (United States)

    Ferguson, Kelly K; Chen, Yin-Hsiu; VanderWeele, Tyler J; McElrath, Thomas F; Meeker, John D; Mukherjee, Bhramar

    2017-03-01

    Mediation analysis is useful for understanding mechanisms and has been used minimally in the study of the environment and disease. We examined mediation of the association between phthalate exposure during pregnancy and preterm birth by oxidative stress. This nested case-control study of preterm birth (n = 130 cases, 352 controls) included women who delivered in Boston, Massachusestts, from 2006 through 2008. Phthalate metabolites and 8-isoprostane, an oxidative stress biomarker, were measured in urine from three visits in pregnancy. We applied four counterfactual mediation methods: method 1, utilizing exposure and mediator averages; method 2, using averages but allowing for an exposure-mediator interaction; method 3, incorporating longitudinal measurements of the exposure and mediator; and method 4, using longitudinal measurements and allowing for an exposure-mediator interaction. We observed mediation of the associations between phthalate metabolites and all preterm birth by 8-isoprostane, with the greatest estimated proportion mediated observed for spontaneous preterm births specifically. Fully utilizing repeated measures of the exposure and mediator improved precision of indirect (i.e., mediated) effect estimates, and including an exposure-mediator interaction increased the estimated proportion mediated. For example, for mono(2-ethyl-carboxy-propyl) phthalate (MECPP), a metabolite of di(2-ethylhexyl) phthalate (DEHP), the percent of the total effect mediated by 8-isoprostane increased from 47% to 60% with inclusion of an exposure-mediator interaction term, in reference to a total adjusted odds ratio of 1.67 or 1.48, respectively. This demonstrates mediation of the phthalate-preterm birth relationship by oxidative stress, and the utility of complex regression models in capturing mediated associations when repeated measures of exposure and mediator are available and an exposure-mediator interaction may exist. Citation: Ferguson KK, Chen YH, VanderWeele TJ, Mc

  20. An L-band SAR for repeat pass deformation measurements on a UAV platform

    Science.gov (United States)

    Wheeler, Kevin; Hensley, Scott; Lou, Yunling

    2004-01-01

    We are proposing to develop a miniaturized polarimetric L-band synthetic aperture radar (SAR) for repeatpass differential interferometric measurements of deformation for rapidly deforming surfaces of geophysical interest such as volcanoes or earthquakes that is to be flown on a unmanned aerial vehicle (UAV or minimally piloted vehicle (MPV).

  1. Repeated measurements of P retention in ponies fed rations with various Ca:P ratios

    NARCIS (Netherlands)

    van Doorn, D A; Schaafstra, F J W C; Wouterse, H; Everts, H; Estepa, J C; Aguilera-Tejero, E; Beynen, A C

    2014-01-01

    This study addresses the question of whether feeding rations rich in P for a period of up to 42 d induces a positive P balance in adult ponies. Biochemical bone markers and parathyroid hormone (PTH; intact as well as whole PTH) were measured to obtain clues as to the effect of P loading on bone meta

  2. Repeated measures of urinary oxidative stress biomarkers during pregnancy and preterm birth.

    Science.gov (United States)

    Ferguson, Kelly K; McElrath, Thomas F; Chen, Yin-Hsiu; Loch-Caruso, Rita; Mukherjee, Bhramar; Meeker, John D

    2015-02-01

    The purpose of this study was to investigate oxidative stress as a mechanism of preterm birth in human subjects; we examined associations between urinary biomarkers of oxidative stress that were measured at multiple time points during pregnancy and preterm birth. This nested case-control study included 130 mothers who delivered preterm and 352 mothers who delivered term who were originally recruited as part of an ongoing prospective birth cohort at Brigham and Women's Hospital. Two biomarkers that included 8-hydroxydeoxyguanosine (8-OHdG) and 8-isoprostane were measured in urine samples that were collected at up to 4 time points (median 10, 18, 26, and 35 weeks) during gestation. Urinary concentrations of 8-isoprostane and 8-OHdG decreased and increased, respectively, as pregnancy progressed. Average levels of 8-isoprostane across pregnancy were associated with increased odds of spontaneous preterm birth (adjusted odds ratio, 6.25; 95% confidence interval, 2.86-13.7), and associations were strongest with levels measured later in pregnancy. Average levels of 8-OHdG were protective against overall preterm birth (adjusted odds ratio, 0.19; 95% confidence interval, 0.10-0.34), and there were no apparent differences in the protective effect in cases of spontaneous preterm birth compared with cases of placental origin. Odds ratios for overall preterm birth were more protective in association with urinary 8-OHdG concentrations that were measured early in pregnancy. Maternal oxidative stress may be an important contributor to preterm birth, regardless of subtype and timing of exposure during pregnancy. The 2 biomarkers that were measured in the present study had opposite associations with preterm birth; an improved understanding of what each represents may help to identify more precisely important mechanisms in the pathway to preterm birth. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Characterization of fetal growth by repeated ultrasound measurements in the wild guinea pig (Cavia aperea).

    Science.gov (United States)

    Schumann, K; Guenther, A; Göritz, F; Jewgenow, K

    2014-08-01

    Fetal growth during pregnancy has previously been studied in the domesticated guinea pig (Cavia aperea f. porcellus) after dissecting pregnant females, but there are no studies describing the fetal growth in their wild progenitor, the wild guinea pig (C aperea). In this study, 50 pregnancies of wild guinea pig sows were investigated using modern ultrasound technique. The two most common fetal growth parameters (biparietal diameter [BPD] and crown-rump-length [CRL]) and uterine position were measured. Data revealed similar fetal growth patterns in the wild guinea pig and domesticated guinea pig in the investigated gestation period, although they differ in reproductive milestones such as gestation length (average duration of pregnancy 68 days), average birth weight, and litter mass. In this study, pregnancy lasted on average 60.2 days with a variance of less than a day (0.96 days). The measured fetal growth parameters are strongly correlated with each (R = 0.91; P guinea pig.

  4. Extended fluctuation theorems for repeated measurements and feedback within Hamiltonian framework

    Energy Technology Data Exchange (ETDEWEB)

    Lahiri, Sourabh, E-mail: sourabhlahiri@gmail.com [Laboratoire de Physico-Chimie Théorique, ESPCI, 10 rue Vauquelin, F-75231 Paris (France); Jayannavar, A.M. [Institute of Physics, Sachivalaya Marg, Bhubaneswar 751005 (India)

    2016-04-29

    We derive the extended fluctuation theorems in presence of multiple measurements and feedback, when the system is governed by Hamiltonian dynamics. We use only the forward phase space trajectories in the derivation. However, to obtain an expression for the efficacy parameter, we must necessarily use the notion of reverse trajectory. Our results show that the correction term appearing in the exponent of the extended fluctuation theorems is non-unique, whereas the physical meaning of the efficacy parameter is unique. - Highlights: • Extended Fluctuation Theorems under multiple measurements and feedback have been derived using Hamiltonian dynamics. • We prove the theorems without using the notion of reverse trajectory. • We show that the correction terms are not unique. • The efficacy parameter is shown to have a unique physical meaning.

  5. Composite tube and plate manufacturing repeatability as determined by precision measurements of thermal strain

    Science.gov (United States)

    Riddle, Lenn A.; Tucker, James R.; Bluth, A. Marcel

    2013-09-01

    Composite materials often carry the reputation of demonstrating high variability in critical material properties. The JWST telescope metering structure is fabricated of several thousand separate composite piece parts. The stringent dimensional stability requirements on the metering structure require the critical thermal strain response of every composite piece be verified either at the billet or piece part level. JWST is a unique composite space structure in that it has required the manufacturing of several hundred composite billets that cover many lots of prepreg and many years of fabrication. The flight billet thermal expansion acceptance criteria limits the coefficient of thermal expansion (CTE) to a tolerance ranging between +/-0.014 ppm/K to +/-0.04 ppm/K around a prescribed nominal when measured from 293 K down to 40 K. The different tolerance values represent different material forms including flat plates and different tube cross-section dimensions. A precision measurement facility was developed that could measure at the required accuracy and at a pace that supported the composite part fabrication rate. The test method and facility is discussed and the results of a statistical process analysis of the flight composite billets are surveyed.

  6. Are exhaled nitric oxide measurements using the portable NIOX MINO repeatable?

    Directory of Open Access Journals (Sweden)

    Raza Abid

    2010-04-01

    Full Text Available Abstract Background Exhaled nitric oxide is a non-invasive marker of airway inflammation and a portable analyser, the NIOX MINO (Aerocrine AB, Solna, Sweden, is now available. This study aimed to assess the reproducibility of the NIOX MINO measurements across age, sex and lung function for both absolute and categorical exhaled nitric oxide values in two distinct groups of children and teenagers. Methods Paired exhaled nitric oxide readings were obtained from 494 teenagers, aged 16-18 years, enrolled in an unselected birth cohort and 65 young people, aged 6-17 years, with asthma enrolled in an interventional asthma management study. Results The birth cohort participants showed a high degree of variability between first and second exhaled nitric oxide readings (mean intra-participant difference 1.37 ppb, 95% limits of agreement -7.61 to 10.34 ppb, although there was very close agreement when values were categorised as low, normal, intermediate or high (kappa = 0.907, p Conclusions The reproducibility of exhaled nitric oxide is poor for absolute values but acceptable when values are categorised as low, normal, intermediate or high in children and teenagers. One measurement is therefore sufficient when using categorical exhaled nitric oxide values to direct asthma management but a mean of at least two measurements is required for absolute values.

  7. Reliability of plasma lipopolysaccharide-binding protein (LBP) from repeated measures in healthy adults.

    Science.gov (United States)

    Citronberg, Jessica S; Wilkens, Lynne R; Lim, Unhee; Hullar, Meredith A J; White, Emily; Newcomb, Polly A; Le Marchand, Loïc; Lampe, Johanna W

    2016-09-01

    Plasma lipopolysaccharide-binding protein (LBP), a measure of internal exposure to bacterial lipopolysaccharide, has been associated with several chronic conditions and may be a marker of chronic inflammation; however, no studies have examined the reliability of this biomarker in a healthy population. We examined the temporal reliability of LBP measured in archived samples from participants in two studies. In Study one, 60 healthy participants had blood drawn at two time points: baseline and follow-up (either three, six, or nine months). In Study two, 24 individuals had blood drawn three to four times over a seven-month period. We measured LBP in archived plasma by ELISA. Test-retest reliability was estimated by calculating the intraclass correlation coefficient (ICC). Plasma LBP concentrations showed moderate reliability in Study one (ICC 0.60, 95 % CI 0.43-0.75) and Study two (ICC 0.46, 95 % CI 0.26-0.69). Restricting the follow-up period improved reliability. In Study one, the reliability of LBP over a three-month period was 0.68 (95 % CI: 0.41-0.87). In Study two, the ICC of samples taken ≤seven days apart was 0.61 (95 % CI 0.29-0.86). Plasma LBP concentrations demonstrated moderate test-retest reliability in healthy individuals with reliability improving over a shorter follow-up period.

  8. Global sensitivity analysis for repeated measures studies with informative drop-out: A semi-parametric approach.

    Science.gov (United States)

    Scharfstein, Daniel; McDermott, Aidan; Díaz, Iván; Carone, Marco; Lunardon, Nicola; Turkoz, Ibrahim

    2017-05-23

    In practice, both testable and untestable assumptions are generally required to draw inference about the mean outcome measured at the final scheduled visit in a repeated measures study with drop-out. Scharfstein et al. (2014) proposed a sensitivity analysis methodology to determine the robustness of conclusions within a class of untestable assumptions. In their approach, the untestable and testable assumptions were guaranteed to be compatible; their testable assumptions were based on a fully parametric model for the distribution of the observable data. While convenient, these parametric assumptions have proven especially restrictive in empirical research. Here, we relax their distributional assumptions and provide a more flexible, semi-parametric approach. We illustrate our proposal in the context of a randomized trial for evaluating a treatment of schizoaffective disorder. © 2017, The International Biometric Society.

  9. Repeated serum creatinine measurement in primary care: Not all patients have chronic renal failure.

    Science.gov (United States)

    Gentille Lorente, Delicia; Gentille Lorente, Jorge; Salvadó Usach, Teresa

    2015-01-01

    To assess the prevalence of kidney failure in patients from a primary care centre in a basic healthcare district with laboratory availability allowing serum creatinine measurements. An observational descriptive cross-sectional study. A basic healthcare district serving 23,807 people aged ≥ 18 years. Prevalence of kidney failure among 17,240 patients having at least one laboratory measurement available was 8.5% (mean age 77.6 ± 12.05 years). In 33.2% of such patients an occult kidney failure was found (98.8% were women). Prevalence of chronic kidney failure among 10,011 patients having at least 2 laboratory measurements available (≥ 3 months apart) was 5.5% with mean age being 80.1 ± 10.0 years (most severely affected patients were those aged 75 to 84); 59.7% were men and 76.3% of cases were in stage 3. An occult kidney failure was found in 5.3% of patients with women being 86.2% of them (a glomerular filtration rate<60 ml/min was estimated for plasma creatinine levels of 0.9 mg/dl or higher). Comparison of present findings to those previously reported demonstrates the need for further studies on the prevalence of overall (chronic and acute) kidney failure in Spain in order to estimate the real scope of the disease. Primary care physicians play a critical role in disease detection, therapy, control and recording (in medical records). MDRD equation is useful and practical to estimate glomerular filtration rate. Copyright © 2015 The Authors. Published by Elsevier España, S.L.U. All rights reserved.

  10. Assessment of individual agreements with repeated measurements based on generalized confidence intervals.

    Science.gov (United States)

    Quiroz, Jorge; Burdick, Richard K

    2009-01-01

    Individual agreement between two measurement systems is determined using the total deviation index (TDI) or the coverage probability (CP) criteria as proposed by Lin (2000) and Lin et al. (2002). We used a variance component model as proposed by Choudhary (2007). Using the bootstrap approach, Choudhary (2007), and generalized confidence intervals, we construct bounds on TDI and CP. A simulation study was conducted to assess whether the bounds maintain the stated type I error probability of the test. We also present a computational example to demonstrate the statistical methods described in the paper.

  11. Prediction Accuracy in Multivariate Repeated-Measures Bayesian Forecasting Models with Examples Drawn from Research on Sleep and Circadian Rhythms

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    Clark Kogan

    2016-01-01

    Full Text Available In study designs with repeated measures for multiple subjects, population models capturing within- and between-subjects variances enable efficient individualized prediction of outcome measures (response variables by incorporating individuals response data through Bayesian forecasting. When measurement constraints preclude reasonable levels of prediction accuracy, additional (secondary response variables measured alongside the primary response may help to increase prediction accuracy. We investigate this for the case of substantial between-subjects correlation between primary and secondary response variables, assuming negligible within-subjects correlation. We show how to determine the accuracy of primary response predictions as a function of secondary response observations. Given measurement costs for primary and secondary variables, we determine the number of observations that produces, with minimal cost, a fixed average prediction accuracy for a model of subject means. We illustrate this with estimation of subject-specific sleep parameters using polysomnography and wrist actigraphy. We also consider prediction accuracy in an example time-dependent, linear model and derive equations for the optimal timing of measurements to achieve, on average, the best prediction accuracy. Finally, we examine an example involving a circadian rhythm model and show numerically that secondary variables can improve individualized predictions in this time-dependent nonlinear model as well.

  12. Prediction Accuracy in Multivariate Repeated-Measures Bayesian Forecasting Models with Examples Drawn from Research on Sleep and Circadian Rhythms.

    Science.gov (United States)

    Kogan, Clark; Kalachev, Leonid; Van Dongen, Hans P A

    2016-01-01

    In study designs with repeated measures for multiple subjects, population models capturing within- and between-subjects variances enable efficient individualized prediction of outcome measures (response variables) by incorporating individuals response data through Bayesian forecasting. When measurement constraints preclude reasonable levels of prediction accuracy, additional (secondary) response variables measured alongside the primary response may help to increase prediction accuracy. We investigate this for the case of substantial between-subjects correlation between primary and secondary response variables, assuming negligible within-subjects correlation. We show how to determine the accuracy of primary response predictions as a function of secondary response observations. Given measurement costs for primary and secondary variables, we determine the number of observations that produces, with minimal cost, a fixed average prediction accuracy for a model of subject means. We illustrate this with estimation of subject-specific sleep parameters using polysomnography and wrist actigraphy. We also consider prediction accuracy in an example time-dependent, linear model and derive equations for the optimal timing of measurements to achieve, on average, the best prediction accuracy. Finally, we examine an example involving a circadian rhythm model and show numerically that secondary variables can improve individualized predictions in this time-dependent nonlinear model as well.

  13. The clinical applicability of a daily summary of patients' self-reported postoperative pain-A repeated measure analysis.

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    Wikström, Lotta; Eriksson, Kerstin; Fridlund, Bengt; Nilsson, Mats; Årestedt, Kristofer; Broström, Anders

    2017-03-23

    (i) To determine whether a central tendency, median, based on patients' self-rated pain is a clinically applicable daily measure to show patients' postoperative pain on the first day after major surgery (ii) and to determine the number of self-ratings required for the calculation of this measure. Perioperative pain traits in medical records are difficult to overview. The clinical applicability of a daily documented summarising measure of patients' self-rated pain scores is little explored. A repeated measure design was carried out at three Swedish country hospitals. Associations between the measures were analysed with nonparametric statistical methods; systematic and individual group changes were analysed separately. Measure I: pain scores at rest and activity postoperative day 1; measure II: retrospective average pain from postoperative day 1. The sample consisted of 190 general surgery patients and 289 orthopaedic surgery patients with a mean age of 65; 56% were men. Forty-four percent had a pre-operative daily intake of analgesia, and 77% used postoperative opioids. A range of 4-9 pain scores seem to be eligible for the calculation of the daily measures of pain. Rank correlations for individual median scores, based on four ratings, vs. retrospective self-rated average pain, were moderate and strengthened with increased numbers of ratings. A systematic group change towards a higher level of reported retrospective pain was significant. The median values were clinically applicable daily measures. The risk of obtaining a higher value than was recalled by patients seemed to be low. Applicability increased with increased frequency of self-rated pain scores and with high-quality pain assessments. The documenting of daily median pain scores at rest and during activity could constitute the basis for obtaining patients' experiences by showing their pain severity trajectories. The measures could also be an important key to predicting postoperative health

  14. Understanding how adherence goals promote adherence behaviours: a repeated measure observational study with HIV seropositive patients

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    Jones Gareth

    2012-08-01

    Full Text Available Abstract Background The extent to which patients follow treatments as prescribed is pivotal to treatment success. An exceptionally high level (> 95% of HIV medication adherence is required to suppress viral replication and protect the immune system and a similarly high level (> 80% of adherence has also been suggested in order to benefit from prescribed exercise programmes. However, in clinical practice, adherence to both often falls below the desirable level. This project aims to investigate a wide range of psychological and personality factors that may lead to adherence/non-adherence to medical treatment and exercise programmes. Methods HIV positive patients who are referred to the physiotherapist-led 10-week exercise programme as part of the standard care are continuously recruited. Data on social cognitive variables (attitude, intention, subjective norms, self-efficacy, and outcome beliefs about the goal and specific behaviours, selected personality factors, perceived quality of life, physical activity, self-reported adherence and physical assessment are collected at baseline, at the end of the exercise programme and again 3 months later. The project incorporates objective measures of both exercise (attendance log and improvement in physical measures such as improved fitness level, weight loss, improved circumferential anthropometric measures and medication adherence (verified by non-invasive hair analysis. Discussion The novelty of this project comes from two key aspects, complemented with objective information on exercise and medication adherence. The project assesses beliefs about both the underlying goal such as following prescribed treatment; and about the specific behaviours such as undertaking the exercise or taking the medication, using both implicit and explicit assessments of patients’ beliefs and attitudes. We predict that i the way people think about the underlying goal of their treatments explains medication and exercise

  15. Repeated measures of inflammation and oxidative stress biomarkers in preeclamptic and normotensive pregnancies.

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    Ferguson, Kelly K; Meeker, John D; McElrath, Thomas F; Mukherjee, Bhramar; Cantonwine, David E

    2017-05-01

    Preeclampsia is a prevalent and enigmatic disease, in part characterized by poor remodeling of the spiral arteries. However, preeclampsia does not always clinically present when remodeling has failed to occur. Hypotheses surrounding the "second hit" that is necessary for the clinical presentation of the disease focus on maternal inflammation and oxidative stress. Yet, the studies to date that have investigated these factors have used cross-sectional study designs or small study populations. In the present study, we sought to explore longitudinal trajectories, beginning early in gestation, of a panel of inflammation and oxidative stress markers in women who went on to have preeclamptic or normotensive pregnancies. We examined 441 subjects from the ongoing LIFECODES prospective birth cohort, which included 50 mothers who experienced preeclampsia and 391 mothers with normotensive pregnancies. Participants provided urine and plasma samples at 4 time points during gestation (median, 10, 18, 26, and 35 weeks) that were analyzed for a panel of oxidative stress and inflammation markers. Oxidative stress biomarkers included 8-isoprostane and 8-hydroxydeoxyguanosine. Inflammation biomarkers included C-reactive protein, the cytokines interleukin-1β, -6, and -10, and tumor necrosis factor-α. We created Cox proportional hazard models to calculate hazard ratios based on time of preeclampsia diagnosis in association with biomarker concentrations at each of the 4 study visits. In adjusted models, hazard ratios of preeclampsia were significantly (Pinflammation biomarkers that were measured at visit 2 (median, 18 weeks; hazard ratios, 1.31-1.83, in association with an interquartile range increase in biomarker). Hazard ratios at this time point were the most elevated for C-reactive protein, for interleukin-1β, -6, and -10, and for the oxidative stress biomarker 8-isoprostane (hazard ratio, 1.68; 95% confidence interval, 1.14-2.48) compared to other time points. Hazard ratios for

  16. C-reactive Protein: Repeated Measurements will Improve Dialysis Patient Care.

    Science.gov (United States)

    Cobo, Gabriela; Qureshi, Abdul Rashid; Lindholm, Bengt; Stenvinkel, Peter

    2016-01-01

    Systemic inflammation is a common feature in the uremic phenotype and associates with poor outcomes. The awareness regarding the importance of inflammation assessment in chronic kidney disease (CKD) patients has risen in recent years, and despite the development of novel biomarkers, C-reactive protein (CRP) is still the most measured inflammatory parameter. Notwithstanding, the possible weak points of CRP determination, this biomarker has demonstrated being useful both for guidance in clinical practice and for risk estimation. In addition, regular determination of CRP among dialysis patients has been associated with better outcomes in different dialysis facilities. Because persistent inflammation may be a silent reflection of various pathophysiologic alterations in CKD, it is crucial that inflammatory markers are regularly monitored and therapeutic attempts be made to target this inflammation.

  17. Repeated heart rate measurement and cardiovascular outcomes in left ventricular systolic dysfunction.

    Science.gov (United States)

    Hamill, Victoria; Ford, Ian; Fox, Kim; Böhm, Michael; Borer, Jeffrey S; Ferrari, Roberto; Komajda, Michel; Steg, Philippe Gabriel; Tavazzi, Luigi; Tendera, Michal; Swedberg, Karl

    2015-10-01

    Elevated resting heart rate is associated with increased cardiovascular risk, particularly in patients with left ventricular systolic dysfunction. Heart rate is not monitored routinely in these patients. We hypothesized that routine monitoring of heart rate would increase its prognostic value in patients with left ventricular systolic dysfunction. We analyzed the relationship between heart rate measurements and a range of adverse cardiovascular outcomes, including hospitalization for worsening heart failure, in the pooled placebo-treated patients from the morBidity-mortality EvAlUaTion of the If inhibitor ivabradine in patients with coronary disease and left ventricULar dysfunction (BEAUTIFUL) trial and Systolic Heart failure treatment with the If inhibitor ivabradine (SHIFT) Trial, using standard and time-varying covariate Cox proportional hazards models. By adjusting for other prognostic factors, models were fitted for baseline heart rate alone or for time-updated heart rate (latest heart rate) alone or corrected for baseline heart rate or for immediate previous time-updated heart rate. Baseline heart rate was strongly associated with all outcomes apart from hospitalization for myocardial infarction. Time-updated heart rate increased the strengths of associations for all outcomes. Adjustment for baseline heart rate or immediate previous time-updated heart rate modestly reduced the prognostic importance of time-updated heart rate. For hospitalization for worsening heart failure, each 5 beats/min increase in baseline heart rate and time-updated heart rate was associated with a 15% (95% confidence interval, 12-18) and 22% (confidence interval, 19-40) increase in risk, respectively. Even after correction, the prognostic value of time-updated heart rate remained greater. In patients with left ventricular systolic dysfunction, time-updated heart rate is more strongly related with adverse cardiovascular outcomes than baseline heart rate. Heart rate should be measured to

  18. Psychological impact and recovery after involvement in a patient safety incident: a repeated measures analysis

    Science.gov (United States)

    Van Gerven, Eva; Bruyneel, Luk; Panella, Massimiliano; Euwema, Martin; Sermeus, Walter; Vanhaecht, Kris

    2016-01-01

    Objective To examine individual, situational and organisational aspects that influence psychological impact and recovery of a patient safety incident on physicians, nurses and midwives. Design Cross-sectional, retrospective surveys of physicians, midwives and nurses. Setting 33 Belgian hospitals. Participants 913 clinicians (186 physicians, 682 nurses, 45 midwives) involved in a patient safety incident. Main outcome measures The Impact of Event Scale was used to retrospectively measure psychological impact of the safety incident at the time of the event and compare it with psychological impact at the time of the survey. Results Individual, situational as well as organisational aspects influenced psychological impact and recovery of a patient safety incident. Psychological impact is higher when the degree of harm for the patient is more severe, when healthcare professionals feel responsible for the incident and among female healthcare professionals. Impact of degree of harm differed across clinicians. Psychological impact is lower among more optimistic professionals. Overall, impact decreased significantly over time. This effect was more pronounced for women and for those who feel responsible for the incident. The longer ago the incident took place, the stronger impact had decreased. Also, higher psychological impact is related with the use of a more active coping and planning coping strategy, and is unrelated to support seeking coping strategies. Rendered support and a support culture reduce psychological impact, whereas a blame culture increases psychological impact. No associations were found with job experience and resilience of the health professional, the presence of a second victim support team or guideline and working in a learning culture. Conclusions Healthcare organisations should anticipate on providing their staff appropriate and timely support structures that are tailored to the healthcare professional involved in the incident and to the specific

  19. Repeat-until-success quantum repeaters

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    Bruschi, David Edward; Barlow, Thomas M.; Razavi, Mohsen; Beige, Almut

    2014-09-01

    We propose a repeat-until-success protocol to improve the performance of probabilistic quantum repeaters. Conventionally, these rely on passive static linear-optics elements and photodetectors to perform Bell-state measurements (BSMs) with a maximum success rate of 50%. This is a strong impediment for entanglement swapping between distant quantum memories. Every time a BSM fails, entanglement needs to be redistributed between the corresponding memories in the repeater link. The key ingredients of our scheme are repeatable BSMs. Under ideal conditions, these turn probabilistic quantum repeaters into deterministic ones. Under realistic conditions, our protocol too might fail. However, using additional threshold detectors now allows us to improve the entanglement generation rate by almost orders of magnitude, at a nominal distance of 1000 km, compared to schemes that rely on conventional BSMs. This improvement is sufficient to make the performance of our scheme comparable to the expected performance of some deterministic quantum repeaters.

  20. A novel AX+/BX- paradigm to assess fear learning and safety-signal processing with repeated-measure designs.

    Science.gov (United States)

    Kazama, Andy M; Schauder, Kimberly B; McKinnon, Michael; Bachevalier, Jocelyne; Davis, Michael

    2013-04-15

    One of the core symptoms of anxiety disorders, such as post-traumatic stress disorder, is the failure to overcome feelings of danger despite being in a safe environment. This deficit likely stems from an inability to fully process safety signals, which are cues in the environment that enable healthy individuals to over-ride fear in aversive situations. Studies examining safety signal learning in rodents, humans, and non-human primates currently rely on between-groups designs. Because repeated-measure designs reduce the number of subjects required, and facilitate a broader range of safety signal studies, the current project sought to develop a repeated-measures safety-signal learning paradigm in non-human primates. Twelve healthy rhesus macaques of both sexes received three rounds of auditory fear-potentiated startle training and testing using an AX+/BX- design with all visual cues. Cue AX was paired with an aversive blast of air, whereas the same X cue in compound with another B cue (BX) signaled the absence of an air blast. Hence, cue B served as a safety signal. Once animals consistently discriminated between the aversive (AX+) and safe (BX-) cues, measured by greater startle amplitude in the presence of AX vs. BX, they were tested for conditioned inhibition by eliciting startle in the presence of a novel ambiguous combined cue (AB). Similar to previous AX+/BX- studies, healthy animals rapidly learned to discriminate between the AX+ and BX- cues as well as demonstrate conditioned inhibition in the presence of the combined AB cue (i.e. lower startle amplitude in the presence of AB vs. AX). Additionally, animals performed consistently across three rounds of testing using three new cues each time. The results validate this novel method that will serve as a useful tool for better understanding the mechanisms for the regulation of fear and anxiety. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. Hepatic 18F-FDG Uptake Measurements on PET/MR: Impact of Volume of Interest Location on Repeatability

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    Liran Domachevsky

    2017-01-01

    Full Text Available Background. To investigate same day 18F-FDG (Fluorodeoxyglucose PET (Positron Emission Tomography/MR (Magnetic Resonance test-retest repeatability of Standardized Uptake Value measurements normalized for body weight (SUV and lean body mass (SUL in different locations in the liver. Methods. This prospective study was IRB approved with written informed consent obtained. 35 patients (20 women and 15 men, 61±11.2 years that performed a whole-body 18F-FDG PET/MR followed by liver-dedicated contrast-enhanced 18F-FDG PET/MR were included. SUV/L max, mean, and peak were measured inferior to, superior to, and at the right portal vein and in the left lobe of the liver. The coefficient of variation (CV and intraclass correlation coefficient (ICC were calculated and Bland-Altman plots were obtained. Results. The variability for SUV/L’s measurements was lowest inferior to the portal vein (<9.2% followed by measurements performed at the level of the portal vein (<14.6%. Conclusion. The area inferior to the portal vein is the most reliable location for hepatic 18F-FDG uptake measurements on PET/MR.

  2. Magnetic Resonance Spectroscopy in Patients with Insomnia: A Repeated Measurement Study.

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    Spiegelhalder, Kai; Regen, Wolfram; Nissen, Christoph; Feige, Bernd; Baglioni, Chiara; Riemann, Dieter; Hennig, Jürgen; Lange, Thomas

    2016-01-01

    Chronic insomnia is one of the most prevalent central nervous system disorders. It is characterized by increased arousal levels, however, the neurobiological causes and correlates of hyperarousal in insomnia remain to be further determined. In the current study, magnetic resonance spectroscopy was used in the morning and evening in a well-characterized sample of 20 primary insomnia patients (12 females; 8 males; 42.7 ± 13.4 years) and 20 healthy good sleepers (12 females; 8 males; 44.1 ± 10.6 years). The most important inhibitory and excitatory neurotransmitters of the central nervous system, γ-aminobutyric acid (GABA) and glutamate/glutamine (Glx), were assessed in the anterior cingulate cortex (ACC) and dorsolateral prefrontal cortex (DLPFC). The primary hypothesis, a diurnal effect on GABA levels in patients with insomnia, could not be confirmed. Moreover, the current results did not support previous findings of altered GABA levels in individuals with insomnia. Exploratory analyses, however, suggested that GABA levels in the ACC may be positively associated with habitual sleep duration, and, thus, reduced GABA levels may be a trait marker of objective sleep disturbances. Moreover, there was a significant GROUP x MEASUREMENT TIME interaction effect on Glx in the DLPFC with increasing Glx levels across the day in the patients but not in the control group. Therefore, Glx levels may reflect hyperarousal at bedtime in those with insomnia. Future confirmatory studies should include larger sample sizes to investigate brain metabolites in different subgroups of insomnia.

  3. Using high-dynamic-range digital repeat photography to measure plant phenology in a subarctic mire.

    Science.gov (United States)

    Garnello, A.; Dye, D. G.; Bogle, R.; Vogel, J.; Saleska, S. R.; Crill, P. M.

    2015-12-01

    A novel Visual Imaging System (VIS) was designed and deployed in a subarctic mire (68° 20' N, 19° 03'E) aimed at cataloging plant biological changes (phenology) and analyzing seasonal color shifts in relation to micrometeorological data along the summer growing season: June-November, 2015. The VIS is designed as a tower-based, solar-powered, automated phenology camera (Phenocam) that collects red, green, blue (RGB) and near-infrared (NIR) landscape images in High Dynamic Range (HDR) with fully programmable temporal resolution. HDR composite images are made through combining a series of rapid-capture photos with incremental increases of exposure times and a fixed focus, minimizing the spatial and visual data lost from shadows or from the over-saturation of light. This visual record of ecosystem phenology stages (Phenophases) is being used to (1) investigate vegetation-dependent spectral indices; (2) establish a cross-year comparison record of Phenophase seasonality; (3) investigate meteorological-dependent vegetation Phenophases; (4) provide ground-truthing measurements that enhance broader spatial-scale remote sensing analyses of subarctic wetlands.

  4. A Finite Mixture of Nonlinear Random Coefficient Models for Continuous Repeated Measures Data.

    Science.gov (United States)

    Kohli, Nidhi; Harring, Jeffrey R; Zopluoglu, Cengiz

    2016-09-01

    Nonlinear random coefficient models (NRCMs) for continuous longitudinal data are often used for examining individual behaviors that display nonlinear patterns of development (or growth) over time in measured variables. As an extension of this model, this study considers the finite mixture of NRCMs that combine features of NRCMs with the idea of finite mixture (or latent class) models. The efficacy of this model is that it allows the integration of intrinsically nonlinear functions where the data come from a mixture of two or more unobserved subpopulations, thus allowing the simultaneous investigation of intra-individual (within-person) variability, inter-individual (between-person) variability, and subpopulation heterogeneity. Effectiveness of this model to work under real data analytic conditions was examined by executing a Monte Carlo simulation study. The simulation study was carried out using an R routine specifically developed for the purpose of this study. The R routine used maximum likelihood with the expectation-maximization algorithm. The design of the study mimicked the output obtained from running a two-class mixture model on task completion data.

  5. Breath acidification in adolescent runners exposed to atmospheric pollution: A prospective, repeated measures observational study

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    Van Sickle David

    2008-03-01

    Full Text Available Abstract Background Vigorous outdoors exercise during an episode of air pollution might cause airway inflammation. The purpose of this study was to examine the effects of vigorous outdoor exercise during peak smog season on breath pH, a biomarker of airway inflammation, in adolescent athletes. Methods We measured breath pH both pre- and post-exercise on ten days during peak smog season in 16 high school athletes engaged in daily long-distance running in a downwind suburb of Atlanta. The association of post-exercise breath pH with ambient ozone and particulate matter concentrations was tested with linear regression. Results We collected 144 pre-exercise and 146 post-exercise breath samples from 16 runners (mean age 14.9 years, 56% male. Median pre-exercise breath pH was 7.58 (interquartile range: 6.90 to 7.86 and did not change significantly after exercise. We observed no significant association between ambient ozone or particulate matter and post-exercise breath pH. However both pre- and post-exercise breath pH were strikingly low in these athletes when compared to a control sample of 14 relatively sedentary healthy adults and to published values of breath pH in healthy subjects. Conclusion Although we did not observe an acute effect of air pollution exposure during exercise on breath pH, breath pH was surprisingly low in this sample of otherwise healthy long-distance runners. We speculate that repetitive vigorous exercise may induce airway acidification.

  6. Repeatability of corticospinal and spinal measures during lengthening and shortening contractions in the human tibialis anterior muscle.

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    Jamie Tallent

    Full Text Available UNLABELLED: Elements of the human central nervous system (CNS constantly oscillate. In addition, there are also methodological factors and changes in muscle mechanics during dynamic muscle contractions that threaten the stability and consistency of transcranial magnetic stimulation (TMS and perpherial nerve stimulation (PNS measures. PURPOSE: To determine the repeatability of TMS and PNS measures during lengthening and shortening muscle actions in the intact human tibialis anterior. METHODS: On three consecutive days, 20 males performed lengthening and shortening muscle actions at 15, 25, 50 and 80% of maximal voluntary contraction (MVC. The amplitude of the Motor Evoked Potentials (MEPs produced by TMS was measured at rest and during muscle contraction at 90° of ankle joint position. MEPs were normalised to Mmax determined with PNS. The corticospinal silent period was recorded at 80% MVC. Hoffman reflex (H-reflex at 10% isometric and 25% shortening and lengthening MVCs, and V-waves during MVCs were also evoked on each of the three days. RESULTS: With the exception of MEPs evoked at 80% shortening MVC, all TMS-derived measures showed good reliability (ICC = 0.81-0.94 from days 2 to 3. Confidence intervals (CI, 95% were lower between days 2 and 3 when compared to days 1 and 2. MEPs significantly increased at rest from days 1 to 2 (P = 0.016 and days 1 to 3 (P = 0.046. The H-reflex during dynamic muscle contraction was reliable across the three days (ICC = 0.76-0.84. V-waves (shortening, ICC = 0.77, lengthening ICC = 0.54 and the H-reflex at 10% isometric MVC (ICC = 0.66 was generally less reliable over the three days. CONCLUSION: Although it is well known that measures of the intact human CNS exhibit moment-to-moment fluctuations, careful experimental arrangements make it possible to obtain consistent and repeatable measurements of corticospinal and spinal excitability in the actively lengthening and shortening human

  7. Are There Linguistic Markers of Suicidal Writing That Can Predict the Course of Treatment? A Repeated Measures Longitudinal Analysis.

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    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.

  8. A Bayesian model for repeated measures zero-inflated count data with application to outpatient psychiatric service use

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    Neelon, Brian H.; O’Malley, A. James; Normand, Sharon-Lise T.

    2009-01-01

    In applications involving count data, it is common to encounter an excess number of zeros. In the study of outpatient service utilization, for example, the number of utilization days will take on integer values, with many subjects having no utilization (zero values). Mixed-distribution models, such as the zero-inflated Poisson (ZIP) and zero-inflated negative binomial (ZINB), are often used to fit such data. A more general class of mixture models, called hurdle models, can be used to model zero-deflation as well as zero-inflation. Several authors have proposed frequentist approaches to fitting zero-inflated models for repeated measures. We describe a practical Bayesian approach which incorporates prior information, has optimal small-sample properties, and allows for tractable inference. The approach can be easily implemented using standard Bayesian software. A study of psychiatric outpatient service use illustrates the methods. PMID:21339863

  9. Detection of quasi-periodic processes in repeated measurements: New approach for the fitting and clusterization of different data

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    Nigmatullin, R.; Rakhmatullin, R.

    2014-12-01

    Many experimentalists were accustomed to think that any independent measurement forms a non-correlated measurement that depends weakly from others. We are trying to reconsider this conventional point of view and prove that similar measurements form a strongly-correlated sequence of random functions with memory. In other words, successive measurements "remember" each other at least their nearest neighbors. This observation and justification on real data help to fit the wide set of data based on the Prony's function. The Prony's decomposition follows from the quasi-periodic (QP) properties of the measured functions and includes the Fourier transform as a partial case. New type of decomposition helps to obtain a specific amplitude-frequency response (AFR) of the measured (random) functions analyzed and each random function contains less number of the fitting parameters in comparison with its number of initial data points. Actually, the calculated AFR can be considered as the generalized Prony's spectrum (GPS), which will be extremely useful in cases where the simple model pretending on description of the measured data is absent but vital necessity of their quantitative description is remained. These possibilities open a new way for clusterization of the initial data and new information that is contained in these data gives a chance for their detailed analysis. The electron paramagnetic resonance (EPR) measurements realized for empty resonator (pure noise data) and resonator containing a sample (CeO2 in our case) confirmed the existence of the QP processes in reality. But we think that the detection of the QP processes is a common feature of many repeated measurements and this new property of successive measurements can attract an attention of many experimentalists. To formulate some general conditions that help to identify and then detect the presence of some QP process in the repeated experimental measurements. To find a functional equation and its solution that

  10. Association between proton magnetic resonance spectroscopy measurements and CAG repeat number in patients with spinocerebellar ataxias 2, 3, or 6.

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    Po-Shan Wang

    Full Text Available The aim of this study was to correlate magnetic resonance spectroscopy (MRS measurements, including that for the N-acetyl aspartate (NAA/creatine (Cr ratio in the vermis (denoted V-NAA, right cerebellar hemisphere (R-NAA, and left (L-NAA cerebellar hemisphere, with the clinical scale for the assessment and rating of ataxia (SARA score for patients with spinocerebellar ataxia (SCA types 2, 3, and 6. A total of 24 patients with SCA2, 48 with SCA3, and 16 with SCA6 were recruited; 12 patients with SCA2, 43 with SCA3, and 8 with SCA6 underwent detailed magnetic resonance neuroimaging. Forty-four healthy, age-matched individuals without history of neurologic disease served as control subjects. V-NAA and patient age were used to calculate the predicted age at which a patient with SCA2 or SCA3 would reach an onset V-NAA value. Results showed the following: the NAA/Cr ratio decreased with increasing age in patients with SCA but not in control subjects; the SARA score increased progressively with age and duration of illness; V-NAA showed a better correlation with SARA score than R-NAA in patients with SCA2 or SCA3; the ratio of age to V-NAA correlated well with CAG repeat number; the retrospectively predicted age of onset for SCA2 and SCA3 was consistent with patient-reported age of onset; R-NAA showed a better correlation with SARA score than V-NAA in patients with SCA6; V-NAA and R-NAA correlated with clinical severity (SARA score in patients with SCA. The correlation between CAG repeat number and age could be expressed as a simple linear function, which might explain previous observations claiming that the greater the CAG repeat number, the earlier the onset of illness and the faster the disease progression. These findings support the use of MRS values to predict age of disease onset and to retrospectively evaluate the actual age of disease onset in SCA.

  11. Association between proton magnetic resonance spectroscopy measurements and CAG repeat number in patients with spinocerebellar ataxias 2, 3, or 6.

    Science.gov (United States)

    Wang, Po-Shan; Chen, Hung-Chieh; Wu, Hsiu-Mei; Lirng, Jiing-Feng; Wu, Yu-Te; Soong, Bing-Wen

    2012-01-01

    The aim of this study was to correlate magnetic resonance spectroscopy (MRS) measurements, including that for the N-acetyl aspartate (NAA)/creatine (Cr) ratio in the vermis (denoted V-NAA), right cerebellar hemisphere (R-NAA), and left (L-NAA) cerebellar hemisphere, with the clinical scale for the assessment and rating of ataxia (SARA) score for patients with spinocerebellar ataxia (SCA) types 2, 3, and 6. A total of 24 patients with SCA2, 48 with SCA3, and 16 with SCA6 were recruited; 12 patients with SCA2, 43 with SCA3, and 8 with SCA6 underwent detailed magnetic resonance neuroimaging. Forty-four healthy, age-matched individuals without history of neurologic disease served as control subjects. V-NAA and patient age were used to calculate the predicted age at which a patient with SCA2 or SCA3 would reach an onset V-NAA value. Results showed the following: the NAA/Cr ratio decreased with increasing age in patients with SCA but not in control subjects; the SARA score increased progressively with age and duration of illness; V-NAA showed a better correlation with SARA score than R-NAA in patients with SCA2 or SCA3; the ratio of age to V-NAA correlated well with CAG repeat number; the retrospectively predicted age of onset for SCA2 and SCA3 was consistent with patient-reported age of onset; R-NAA showed a better correlation with SARA score than V-NAA in patients with SCA6; V-NAA and R-NAA correlated with clinical severity (SARA score) in patients with SCA. The correlation between CAG repeat number and age could be expressed as a simple linear function, which might explain previous observations claiming that the greater the CAG repeat number, the earlier the onset of illness and the faster the disease progression. These findings support the use of MRS values to predict age of disease onset and to retrospectively evaluate the actual age of disease onset in SCA.

  12. Diffusion-weighted magnetic resonance imaging for assessment of lung lesions: repeatability of the apparent diffusion coefficient measurement

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    Bernardin, L.; Douglas, N.H.M.; Collins, D.J.; Giles, S.L.; O' Flynn, E.A.M.; Orton, M.; DeSouza, N.M. [Institute of Cancer Research and Royal Marsden NHS Foundation Trust, CRUK and EPSRC Cancer Imaging Centre, Surrey (United Kingdom)

    2014-02-15

    To establish repeatability of apparent diffusion coefficients (ADCs) acquired from free-breathing diffusion-weighted magnetic resonance imaging (DW-MRI) in malignant lung lesions and investigate effects of lesion size, location and respiratory motion. Thirty-six malignant lung lesions (eight patients) were examined twice (1- to 5-h interval) using T1-weighted, T2-weighted and axial single-shot echo-planar DW-MRI (b = 100, 500, 800 s/mm{sup 2}) during free-breathing. Regions of interest around target lesions on computed b = 800 s/mm{sup 2} images by two independent observers yielded ADC values from maps (pixel-by-pixel fitting using all b values and a mono-exponential decay model). Intra- and inter-observer repeatability was assessed per lesion, per patient and by lesion size (> or <2 cm) or location. ADCs were similar between observers (mean ± SD, 1.15 ± 0.28 x 10{sup -3} mm{sup 2}/s, observer 1; 1.15 ± 0.29 x 10{sup -3} mm{sup 2}/s, observer 2). Intra-observer coefficients of variation of the mean [median] ADC per lesion and per patient were 11 % [11.4 %], 5.7 % [5.7 %] for observer 1 and 9.2 % [9.5 %], 3.9 % [4.7 %] for observer 2 respectively; inter-observer values were 8.9 % [9.3 %] (per lesion) and 3.0 % [3.7 %] (per patient). Inter-observer coefficient of variation (CoV) was greater for lesions <2 cm (n = 20) compared with >2 cm (n = 16) (10.8 % vs 6.5 % ADC{sub mean}, 11.3 % vs 6.7 % ADC{sub median}) and for mid (n = 14) vs apical (n = 9) or lower zone (n = 13) lesions (13.9 %, 2.7 %, 3.8 % respectively ADC{sub mean}; 14.2 %, 2.8 %, 4.7 % respectively ADC{sub median}). Free-breathing DW-MRI of whole lung achieves good intra- and inter-observer repeatability of ADC measurements in malignant lung tumours. (orig.)

  13. Accuracy and repeatability of quantitative fluoroscopy for the measurement of sagittal plane translation and finite centre of rotation in the lumbar spine.

    Science.gov (United States)

    Breen, Alexander; Breen, Alan

    2016-07-01

    Quantitative fluoroscopy (QF) was developed to measure intervertebral mechanics in vivo and has been found to have high repeatability and accuracy for the measurement of intervertebral rotations. However, sagittal plane translation and finite centre of rotation (FCR) are potential measures of stability but have not yet been fully validated for current QF. This study investigated the repeatability and accuracy of QF for measuring these variables. Repeatability was assessed from L2-S1 in 20 human volunteers. Accuracy was investigated using 10 consecutive measurements from each of two pairs of linked and instrumented dry human vertebrae as reference; one which tilted without translation and one which translated without tilt. The results found intra- and inter-observer repeatability for translation to be 1.1mm or less (SEM) with fair to substantial reliability (ICC 0.533-0.998). Intra-observer repeatability of FCR location for inter-vertebral rotations of 5° and above ranged from 1.5mm to 1.8mm (SEM) with moderate to substantial reliability (ICC 0.626-0.988). Inter-observer repeatability for FCR ranged from 1.2mm to 5.7mm, also with moderate to substantial reliability (ICC 0.621-0.878). Reliability was substantial (ICC>0.81) for 10/16 measures for translation and 5/8 for FCR location. Accuracy for translation was 0.1mm (fixed centre) and 2.2mm (moveable centre), with an FCR error of 0.3mm(x) and 0.4mm(y) (fixed centre). This technology was found to have a high level of accuracy and with a few exceptions, moderate to substantial repeatability for the measurement of translation and FCR from fluoroscopic motion sequences.

  14. The use of portable NIRS to measure muscle oxygenation and haemodynamics during a repeated sprint running test.

    Science.gov (United States)

    Jones, Ben; Hesford, Catherine M; Cooper, Chris E

    2013-01-01

    Portable near-infrared spectroscopy (NIRS) devices were originally developed for use in exercise and sports science by Britton Chance in the 1990s (the RunMan and microRunman series). However, only recently with the development of more robust, and wireless systems, has the routine use in elite sport become possible. As with the medical use of NIRS, finding applications of the technology that are relevant to practitioners is the key issue. One option is to use NIRS to track exercise training-induced adaptations in muscle. Portable NIRS devices enable monitoring during the normal 'field' routine uses to assess fitness, such as repeat sprint shuttle tests. Knowledge about the acute physiological responses to these specific tests has practical applications within team sport training prescription, where development of both central and peripheral determinants of high-intensity intermittent exercise needs to be considered. The purpose of this study was to observe NIRS-detected parameters during a repeat sprint test. We used the PortaMon, a two wavelength spatially resolved NIR spectrometer manufactured by Artinis Inc., to assess NIR changes in the gastrocnemius muscle of both the left and right leg during high-intensity running. Six university standard rugby players were assessed (age 20 ± 1.5 years; height 183 ± 1.0 cm; weight 89.4 ± 5.8 kg; body fat 12.2 ± 3.0 %); the subjects completed nine repeated shuttle runs, which incorporated forward, backward and change of direction movements. Individual sprint time, total time to complete test, blood lactate response (BL), heart rate values (HR) and haemoglobin variables (ΔHHb, ΔtHb, ΔHbO2 and ΔTSI%) were measured. Total time to complete the test was 260 ± 20 s, final blood lactate was 14.3 ± 2.8 mM, and maximal HR 182 ± 5 bpm. NIRS variables displayed no differences between right and left legs. During the test, the group-averaged data showed a clear decrease in HbO2 (max. decrease 11.41 ± 4.95 μM), increase in HHb

  15. How integrated are behavioral and endocrine stress response traits? A repeated measures approach to testing the stress-coping style model.

    Science.gov (United States)

    Boulton, Kay; Couto, Elsa; Grimmer, Andrew J; Earley, Ryan L; Canario, Adelino V M; Wilson, Alastair J; Walling, Craig A

    2015-02-01

    It is widely expected that physiological and behavioral stress responses will be integrated within divergent stress-coping styles (SCS) and that these may represent opposite ends of a continuously varying reactive-proactive axis. If such a model is valid, then stress response traits should be repeatable and physiological and behavioral responses should also change in an integrated manner along a major axis of among-individual variation. While there is some evidence of association between endocrine and behavioral stress response traits, few studies incorporate repeated observations of both. To test this model, we use a multivariate, repeated measures approach in a captive-bred population of Xiphophorus birchmanni. We quantify among-individual variation in behavioral stress response to an open field trial (OFT) with simulated predator attack (SPA) and measure waterborne steroid hormone levels (cortisol, 11-ketotestosterone) before and after exposure. Under the mild stress stimulus (OFT), (multivariate) behavioral variation among individuals was consistent with a strong axis of personality (shy-bold) or coping style (reactive-proactive) variation. However, behavioral responses to a moderate stressor (SPA) were less repeatable, and robust statistical support for repeatable endocrine state over the full sampling period was limited to 11-ketotestosterone. Although post hoc analysis suggested cortisol expression was repeatable over short time periods, qualitative relationships between behavior and glucocorticoid levels were counter to our a priori expectations. Thus, while our results clearly show among-individual differences in behavioral and endocrine traits associated with stress response, the correlation structure between these is not consistent with a simple proactive-reactive axis of integrated stress-coping style. Additionally, the low repeatability of cortisol suggests caution is warranted if single observations (or indeed repeat measures over short sampling

  16. Repeated-sprint cycling does not induce respiratory muscle fatigue in active adults: measurements from the powerbreathe® inspiratory muscle trainer.

    Science.gov (United States)

    Minahan, Clare; Sheehan, Beth; Doutreband, Rachel; Kirkwood, Tom; Reeves, Daniel; Cross, Troy

    2015-03-01

    This study examined respiratory muscle strength using the POWERbreathe® inspiratory muscle trainer (i.e., 'S-Index') before and after repeated-sprint cycling for comparison with maximal inspiratory pressure (MIP) values obtained during a Mueller maneuver. The S-Index was measured during six trials across two sessions using the POWERbreathe® and MIP was measured during three trials in a single session using a custom-made manometer in seven recreationally active adults. Global respiratory muscle strength was measured using both devices before and after the performance of sixteen, 6-s sprints on a cycle ergometer. Intraclass correlation coefficients for the POWERbreathe® S-index indicated excellent (p Repeated-sprint cycling had no effect on respiratory muscle strength as measured by the POWERbreathe® (p > 0.99) and during the Mueller maneuver (p > 0.99). The POWERbreathe® S-Index is a moderately reliable, but not equivalent, measure of MIP determined during a Mueller maneuver. Furthermore, repeated-sprint cycling does not induce globalized respiratory muscle fatigue in recreationally-active adults. Key pointsThe S-Index as measured by the POWERbreathe® is a reliable measure of respiratory muscle strengthThe S-Index does not accurately reflect maximal inspiratory pressure obtained from a Mueller maneuverRepeated-sprint cycling does not induce respiratory muscle fatigue as measured by the POWERbreathe® and the Manometer.

  17. Ambient particulate air pollution and circulating antioxidant enzymes: A repeated-measure study in healthy adults in Beijing, China.

    Science.gov (United States)

    Wu, Shaowei; Wang, Bin; Yang, Di; Wei, Hongying; Li, Hongyu; Pan, Lu; Huang, Jing; Wang, Xin; Qin, Yu; Zheng, Chanjuan; Shima, Masayuki; Deng, Furong; Guo, Xinbiao

    2016-01-01

    The association of systemic antioxidant activity with ambient air pollution has been unclear. A panel of 40 healthy college students underwent repeated blood collection for 12 occasions under three exposure scenarios before and after relocating from a suburban area to an urban area in Beijing, China in 2010-2011. We measured various air pollutants including fine particles (PM2.5) and determined circulating levels of antioxidant enzymes extracellular superoxide dismutase (EC-SOD) and glutathione peroxidase 1 (GPX1) in the laboratory. An interquartile range increase of 63.4 μg/m(3) at 3-d PM2.5 moving average was associated with a 6.3% (95% CI: 0.6, 12.4) increase in EC-SOD and a 5.5% (95% CI: 1.3, 9.8) increase in GPX1. Several PM2.5 chemical constituents, including negative ions (nitrate and chloride) and metals (e.g., iron and strontium), were consistently associated with increases in EC-SOD and GPX1. Our results support activation of circulating antioxidant enzymes following exposure to particulate air pollution. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. A method to construct a points system to predict cardiovascular disease considering repeated measures of risk factors

    Science.gov (United States)

    Carbayo-Herencia, Julio Antonio; Vigo, Maria Isabel; Gil-Guillén, Vicente Francisco

    2016-01-01

    Current predictive models for cardiovascular disease based on points systems use the baseline situation of the risk factors as independent variables. These models do not take into account the variability of the risk factors over time. Predictive models for other types of disease also exist that do consider the temporal variability of a single biological marker in addition to the baseline variables. However, due to their complexity these other models are not used in daily clinical practice. Bearing in mind the clinical relevance of these issues and that cardiovascular diseases are the leading cause of death worldwide we show the properties and viability of a new methodological alternative for constructing cardiovascular risk scores to make predictions of cardiovascular disease with repeated measures of the risk factors and retaining the simplicity of the points systems so often used in clinical practice (construction, statistical validation by simulation and explanation of potential utilization). We have also applied the system clinically upon a set of simulated data solely to help readers understand the procedure constructed. PMID:26893963

  19. Are diagnostic criteria for acute malnutrition affected by hydration status in hospitalized children? A repeated measures study

    Directory of Open Access Journals (Sweden)

    Fegan Gregory

    2011-09-01

    Full Text Available Abstract Introduction Dehydration and malnutrition commonly occur together among ill children in developing countries. Dehydration (change in total body water is known to alter weight. Although muscle tissue has high water content, it is not known whether mid-upper arm circumference (MUAC may be altered by changes in tissue hydration. We aimed to determine whether rehydration alters MUAC, MUAC Z score (MUACz, weight-for-length Z-score (WFLz and classification of nutritional status among hospitalised Kenyan children admitted with signs of dehydration. Study procedure We enrolled children aged from 3 months to 5 years admitted to a rural Kenyan district hospital with clinical signs compatible with dehydration, and without kwashiorkor. Anthropometric measurements were taken at admission and repeated after 48 hours of treatment, which included rehydration by WHO protocols. Changes in weight observed during this period were considered to be due to changes in hydration status. Results Among 325 children (median age 11 months the median weight gain (rehydration after 48 hours was 0.21 kg, (an increase of 2.9% of admission body weight. Each 1% change in weight was associated with a 0.40 mm (95% CI: 0.30 to 0.44 mm, p Conclusion MUAC is less affected by dehydration than WFLz and is therefore more suitable for nutritional assessment of ill children. However, both WFLz and MUAC misclassify SAM among dehydrated children. Nutritional status should be re-evaluated following rehydration, and management adjusted accordingly.

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

    Science.gov (United States)

    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.

  1. Diabetic Foot Prevention: Repeatability of the Loran Platform Plantar Pressure and Load Distribution Measurements in Nondiabetic Subjects during Bipedal Standing—A Pilot Study

    Directory of Open Access Journals (Sweden)

    Martha Zequera

    2011-01-01

    Full Text Available This study was designed to assess the repeatability of the Loran Platform and evaluate the variability of plantar pressure and postural balance, during barefoot standing in nondiabetic subjects, for future diabetic foot clinical evaluation. Measurements were taken for eight nondiabetic subjects (4 females, 4 males, aged 47±7.2 years who had no musculoskeletal symptoms. Five variables were measured with the platform in the barefoot standing position. Ten measurements were taken using two different techniques for feet and posture positioning, during three sessions, once a week. For most measurements, no significant effect over time was found with Student's t-test (P<.000125. The ANOVA test of statistical significance confirmed that measurement differences between subjects showed higher variations than measurements taken from the same subject (P<.001. The measurements taken by the Loran Platform system were found to be repeatable.

  2. Polycarbonate modified with crystallisable bis-ester tetra-amide units in a reaction extrusion process

    NARCIS (Netherlands)

    Zuiderduin, W.C.J.; Gaymans, R.J.

    2008-01-01

    Dry blends of polycarbonate (PC) and a bis-ester tetra-amide were extruded at 305 °C with a mini twin screw extruder. The bis-ester tetra-amide diamide (T6T6T-dimethyl) was composed of two and a half repeat units of Nylon 6,T and had methyl ester endgroups. During the extrusion, a

  3. Repeated measurements of blood lactate concentration as a prognostic marker in horses with acute colitis evaluated with classification and regression trees (CART) and random forest analysis.

    Science.gov (United States)

    Petersen, M B; Tolver, A; Husted, L; Tølbøll, T H; Pihl, T H

    2016-07-01

    The objective of this study was to investigate the prognostic value of single and repeated measurements of blood l-lactate (Lac) and ionised calcium (iCa) concentrations, packed cell volume (PCV) and plasma total protein (TP) concentration in horses with acute colitis. A total of 66 adult horses admitted with acute colitis (2 mmol/L (sensitivity, 0.72; specificity, 0.8). In conclusion, blood lactate concentration measured at admission and repeated 6 h later aided the prognostic evaluation of horses with acute colitis in this population with a very high mortality rate. This should allow clinicians to give a more reliable prognosis for the horse.

  4. Cardiac output measurement in newborn infants using the ultrasonic cardiac output monitor: an assessment of agreement with conventional echocardiography, repeatability and new user experience.

    Science.gov (United States)

    Patel, Neil; Dodsworth, Melissa; Mills, John F

    2011-05-01

    To assess (1) agreement between the ultrasonic cardiac output monitor (USCOM) 1A device for measurement of cardiac output in newborn infants and conventional echocardiography (ECHO), (2) repeatability of USCOM measurements and (3) agreement between novice and expert users of the USCOM. A prospective observational study. The Neonatal Unit at the Royal Children's Hospital, Melbourne, Australia. 56 term and near-term infants, with no evidence of structural or functional cardiovascular disease, or haemodynamic shunts. Agreement between ECHO and USCOM was assessed by paired measurements of ventricular outputs by a single experienced user. Repeatability was assessed using five repeated measurements in 10 infants. Agreement between five novices and one expert user was assessed by paired USCOM measurements over 30 training measurements. Agreement between USCOM and ECHO for left ventricular output (LVO) was (bias, ±limits of agreement, mean % error): 14, ±108 ml/kg/min, 43%, and for right ventricular output (RVO): -59, ±160, ml/kg/min, 57%. Intra-observer repeatability was 6.7% for USCOM LVO and 3.6% for ECHO LVO. After five training measurements, the mean difference between USCOM measures of LVO by novice and expert users was less than 50 ml/kg/min, but with variability. Repeatability of USCOM measures is high in newborn infants. New users can be trained quickly, but with high inter-user variability. Agreement between USCOM and conventional ECHO is broad, and worse for RVO and LVO. Further studies are required to assess the ability of the device to detect clinically significant changes in infant cardiac output.

  5. Effects of CAG repeat length, HTT protein length and protein context on cerebral metabolism measured using magnetic resonance spectroscopy in transgenic mouse models of Huntington's disease.

    Science.gov (United States)

    Jenkins, Bruce G; Andreassen, Ole A; Dedeoglu, Alpaslan; Leavitt, Blair; Hayden, Michael; Borchelt, David; Ross, Christopher A; Ferrante, Robert J; Beal, M Flint

    2005-10-01

    Huntington's disease is a neurodegenerative illness caused by expansion of CAG repeats at the N-terminal end of the protein huntingtin. We examined longitudinal changes in brain metabolite levels using in vivo magnetic resonance spectroscopy in five different mouse models. There was a large (>50%) exponential decrease in N-acetyl aspartate (NAA) with time in both striatum and cortex in mice with 150 CAG repeats (R6/2 strain). There was a linear decrease restricted to striatum in N171-82Q mice with 82 CAG repeats. Both the exponential and linear decreases of NAA were paralleled in time by decreases in neuronal area measured histologically. Yeast artificial chromosome transgenic mice with 72 CAG repeats, but low expression levels, had less striatal NAA loss than the N171-82Q mice (15% vs. 43%). We evaluated the effect of gene context in mice with an approximate 146 CAG repeat on the hypoxanthine phosphoribosyltransferase gene (HPRT). HPRT mice developed an obese phenotype in contrast to weight loss in the R6/2 and N171-82Q mice. These mice showed a small striatal NAA loss (21%), and a possible increase in brain lipids detectable by magnetic resonance (MR) spectroscopy and decreased brain water T1. Our results indicate profound metabolic defects that are strongly affected by CAG repeat length, as well as gene expression levels and protein context.

  6. Detecting variable responses in time-series using repeated measures ANOVA: Application to physiologic challenges [version 2; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Paul M. Macey

    2016-07-01

    Full Text Available We present an approach to analyzing physiologic timetrends recorded during a stimulus by comparing means at each time point using repeated measures analysis of variance (RMANOVA. The approach allows temporal patterns to be examined without an a priori model of expected timing or pattern of response. The approach was originally applied to signals recorded from functional magnetic resonance imaging (fMRI volumes-of-interest (VOI during a physiologic challenge, but we have used the same technique to analyze continuous recordings of other physiological signals such as heart rate, breathing rate, and pulse oximetry. For fMRI, the method serves as a complement to whole-brain voxel-based analyses, and is useful for detecting complex responses within pre-determined brain regions, or as a post-hoc analysis of regions of interest identified by whole-brain assessments. We illustrate an implementation of the technique in the statistical software packages R and SAS. VOI timetrends are extracted from conventionally preprocessed fMRI images. A timetrend of average signal intensity across the VOI during the scanning period is calculated for each subject. The values are scaled relative to baseline periods, and time points are binned. In SAS, the procedure PROC MIXED implements the RMANOVA in a single step. In R, we present one option for implementing RMANOVA with the mixed model function “lme”. Model diagnostics, and predicted means and differences are best performed with additional libraries and commands in R; we present one example. The ensuing results allow determination of significant overall effects, and time-point specific within- and between-group responses relative to baseline. We illustrate the technique using fMRI data from two groups of subjects who underwent a respiratory challenge. RMANOVA allows insight into the timing of responses and response differences between groups, and so is suited to physiologic testing paradigms eliciting complex

  7. The Effects of Group Leader Learning Style on Student Knowledge Gain in a Leadership Camp Setting: A Repeated-Measures Experiment

    Science.gov (United States)

    Brown, Nicholas R.; Terry, Robert, Jr.

    2013-01-01

    Many state FFA associations conduct summer camps focusing on leadership and personal development for FFA members. Interestingly, little research has been conducted on the impact or outcomes of these common activities. The purpose of this split-plot factorial repeated-measures experiment was to assess the level of campers' learning of the…

  8. Power and sample size for the S:T repeated measures design combined with a linear mixed-effects model allowing for missing data.

    Science.gov (United States)

    Tango, Toshiro

    2017-02-13

    Tango (Biostatistics 2016) proposed a new repeated measures design called the S:T repeated measures design, combined with generalized linear mixed-effects models and sample size calculations for a test of the average treatment effect that depend not only on the number of subjects but on the number of repeated measures before and after randomization per subject used for analysis. The main advantages of the proposed design combined with the generalized linear mixed-effects models are (1) it can easily handle missing data by applying the likelihood-based ignorable analyses under the missing at random assumption and (2) it may lead to a reduction in sample size compared with the simple pre-post design. In this article, we present formulas for calculating power and sample sizes for a test of the average treatment effect allowing for missing data within the framework of the S:T repeated measures design with a continuous response variable combined with a linear mixed-effects model. Examples are provided to illustrate the use of these formulas.

  9. Predictors and Variability of Repeat Measurements of Urinary Phenols and Parabens in a Cohort of Shanghai Women and Men

    Science.gov (United States)

    Buckley, Jessie P.; Yang, Gong; Liao, Linda M.; Satagopan, Jaya; Calafat, Antonia M.; Matthews, Charles E.; Cai, Qiuyin; Ji, Bu-Tian; Cai, Hui; Wolff, Mary S.; Rothman, Nathaniel; Zheng, Wei; Xiang, Yong-Bing; Shu, Xiao-Ou; Gao, Yu-Tang; Chow, Wong-Ho

    2014-01-01

    , under certain circumstances, among women. Citation: Engel LS, Buckley JP, Yang G, Liao LM, Satagopan J, Calafat AM, Matthews CE, Cai Q, Ji BT, Cai H, Engel SM, Wolff MS, Rothman N, Zheng W, Xiang YB, Shu XO, Gao YT, Chow WH. 2014. Predictors and variability of repeat measurements of urinary phenols and parabens in a cohort of Shanghai women and men. Environ Health Perspect 122:733–740; http://dx.doi.org/10.1289/ehp.1306830 PMID:24659570

  10. A review of the reporting and handling of missing data in cohort studies with repeated assessment of exposure measures

    Directory of Open Access Journals (Sweden)

    Karahalios Amalia

    2012-07-01

    Full Text Available Abstract Background Retaining participants in cohort studies with multiple follow-up waves is difficult. Commonly, researchers are faced with the problem of missing data, which may introduce biased results as well as a loss of statistical power and precision. The STROBE guidelines von Elm et al. (Lancet, 370:1453-1457, 2007; Vandenbroucke et al. (PLoS Med, 4:e297, 2007 and the guidelines proposed by Sterne et al. (BMJ, 338:b2393, 2009 recommend that cohort studies report on the amount of missing data, the reasons for non-participation and non-response, and the method used to handle missing data in the analyses. We have conducted a review of publications from cohort studies in order to document the reporting of missing data for exposure measures and to describe the statistical methods used to account for the missing data. Methods A systematic search of English language papers published from January 2000 to December 2009 was carried out in PubMed. Prospective cohort studies with a sample size greater than 1,000 that analysed data using repeated measures of exposure were included. Results Among the 82 papers meeting the inclusion criteria, only 35 (43% reported the amount of missing data according to the suggested guidelines. Sixty-eight papers (83% described how they dealt with missing data in the analysis. Most of the papers excluded participants with missing data and performed a complete-case analysis (n = 54, 66%. Other papers used more sophisticated methods including multiple imputation (n = 5 or fully Bayesian modeling (n = 1. Methods known to produce biased results were also used, for example, Last Observation Carried Forward (n = 7, the missing indicator method (n = 1, and mean value substitution (n = 3. For the remaining 14 papers, the method used to handle missing data in the analysis was not stated. Conclusions This review highlights the inconsistent reporting of missing data in cohort studies and the continuing

  11. A review of the reporting and handling of missing data in cohort studies with repeated assessment of exposure measures.

    Science.gov (United States)

    Karahalios, Amalia; Baglietto, Laura; Carlin, John B; English, Dallas R; Simpson, Julie A

    2012-07-11

    Retaining participants in cohort studies with multiple follow-up waves is difficult. Commonly, researchers are faced with the problem of missing data, which may introduce biased results as well as a loss of statistical power and precision. The STROBE guidelines von Elm et al. (Lancet, 370:1453-1457, 2007); Vandenbroucke et al. (PLoS Med, 4:e297, 2007) and the guidelines proposed by Sterne et al. (BMJ, 338:b2393, 2009) recommend that cohort studies report on the amount of missing data, the reasons for non-participation and non-response, and the method used to handle missing data in the analyses. We have conducted a review of publications from cohort studies in order to document the reporting of missing data for exposure measures and to describe the statistical methods used to account for the missing data. A systematic search of English language papers published from January 2000 to December 2009 was carried out in PubMed. Prospective cohort studies with a sample size greater than 1,000 that analysed data using repeated measures of exposure were included. Among the 82 papers meeting the inclusion criteria, only 35 (43%) reported the amount of missing data according to the suggested guidelines. Sixty-eight papers (83%) described how they dealt with missing data in the analysis. Most of the papers excluded participants with missing data and performed a complete-case analysis (n=54, 66%). Other papers used more sophisticated methods including multiple imputation (n=5) or fully Bayesian modeling (n=1). Methods known to produce biased results were also used, for example, Last Observation Carried Forward (n=7), the missing indicator method (n=1), and mean value substitution (n=3). For the remaining 14 papers, the method used to handle missing data in the analysis was not stated. This review highlights the inconsistent reporting of missing data in cohort studies and the continuing use of inappropriate methods to handle missing data in the analysis. Epidemiological journals

  12. Analyzing repeated data collected by mobile phones and frequent text messages. An example of Low back pain measured weekly for 18 weeks

    DEFF Research Database (Denmark)

    Axén, Iben; Bodin, Lennart; Kongsted, Alice

    2012-01-01

    ABSTRACT: BACKGROUND: Repeated data collection is desirable when monitoring fluctuating conditions. Mobile phones can be used to gather such data from large groups of respondents by sending and receiving frequently repeated short questions and answers as text messages. The analysis of repeated data...... for the clinical researcher in order for complex outcome measures to be interpreted in a clinically meaningful way. METHODS: A model data set was formed using data from two clinical studies, where patients with low back pain were followed with weekly text messages for 18 weeks. Different research questions...... questions with appropriate analytical methods 1: How many days with pain do patients experience? This question was answered with data summaries. 2: What is the proportion of participants "recovered" at a specific time point? This question was answered using logistic regression analysis. 3: What is the time...

  13. Evaluation, including effects of storage and repeated freezing and thawing, of a method for measurement of urinary creatinine

    DEFF Research Database (Denmark)

    Garde, A H; Hansen, Åse Marie; Kristiansen, J

    2003-01-01

    The aims of this study were to elucidate to what extent storage and repeated freezing and thawing influenced the concentration of creatinine in urine samples and to evaluate the method for determination of creatinine in urine. The creatinine method was based on the well-known Jaffe's reaction and...

  14. Heart rate variability and DNA methylation levels are altered after short-term metal fume exposure among occupational welders: a repeated-measures panel study

    OpenAIRE

    2014-01-01

    Background: In occupational settings, boilermakers are exposed to high levels of metallic fine particulate matter (PM2.5) generated during the welding process. The effect of welding PM2.5 on heart rate variability (HRV) has been described, but the relationship between PM2.5, DNA methylation, and HRV is not known. Methods: In this repeated-measures panel study, we recorded resting HRV and measured DNA methylation levels in transposable elements Alu and long interspersed nuclear element-1 (LINE...

  15. Repeated measures dose-finding design with time-trend detection in the presence of correlated toxicity data.

    Science.gov (United States)

    Yin, Jun; Paoletti, Xavier; Sargent, Daniel J; Mandrekar, Sumithra J

    2017-08-01

    Phase I trials are designed to determine the safety, tolerability, and recommended phase 2 dose of therapeutic agents for subsequent testing. The dose-finding paradigm has thus traditionally focused on identifying the maximum tolerable dose of an agent or combination therapy under the assumption that there is a non-decreasing relationship between dose-toxicity and dose-efficacy. The dose is typically determined based on the probability of severe toxicity observed during the first treatment cycle. A novel endpoint, the total toxicity profile, was previously developed to account for the multiple toxicity types and grades experienced in the first cycle. More recently, this was extended to a repeated measures design based on the total toxicity profile to account for longitudinal toxicities over multiple treatment cycles in the absence of within-patient correlation. In this work, we propose to extend the design in the presence of within-patient correlation. Furthermore, we provide a framework to detect a toxicity time trend (toxicity increasing, decreasing, or stable) over multiple treatment cycles. We utilize a linear mixed model in the Bayesian framework, with the addition of Bayesian risk functions for decision-making in dose assignment. The performance of this design was evaluated using simulation studies and real data from a phase I trial. We demonstrated that using available toxicity data from all cycles of treatment improves the accuracy of maximum tolerated dose identification and allows for the detection of a time trend. The performance is consistent regardless of the strength of the within-patient correlation. In addition, the use of a quasi-continuous total toxicity profile score significantly increased the power to detect time trends compared to when binary data only were used. The increased interest in molecularly targeted agents and immunotherapies in oncology necessitates innovative phase I study designs. Our proposed framework provides a tool to tackle

  16. XENON ANESTHESIA IN CHILDREN: BIS-MONITORING

    Directory of Open Access Journals (Sweden)

    V. G. Bagaev

    2013-01-01

    Full Text Available We conducted 60 low-flow xenon anesthesias in children of 1-18 years of age. We measured the sedation level using bispectral (BIS index and clinically on the stage of induction, xenon anesthesia maintenance and during recovery. The trial showed that, according to the clinical and BIS-monitoring data, sevoflurane inhalational induction in children of 1-5 years of age and propofol intravenous induction in children of 6-18 years of age provides children with the required sedation level. BIS index objectively reflects intensity of the sedative component of an anesthesia both in the junior and the senior age groups on the stages of xenon anesthesia maintenance and during recovery.

  17. Young investigator challenge: Atypia of undetermined significance in thyroid FNA: Standardized terminology without standardized management--a closer look at repeat FNA and quality measures.

    Science.gov (United States)

    Brandler, Tamar C; Aziz, Mohamed S; Coutsouvelis, Constantinos; Rosen, Lisa; Rafael, Oana C; Souza, Fabiola; Jelloul, Fatima-Zahra; Klein, Melissa A

    2016-01-01

    The Bethesda system (TBS) for the reporting of thyroid cytopathology established the category of atypia of undetermined significance (AUS) with a 7% target rate and a 5% to 15% implied malignancy risk. Recent literature has reported a broad range of AUS rates, subsequent malignancy rates, and discrepant results from repeat fine-needle aspiration (FNA) versus surgical follow-up. Therefore, this study examined AUS data from the Hofstra North Shore-LIJ School of Medicine to determine the best clinical follow-up. Thyroid aspirates interpreted as AUS in 2012-2014 at the Hofstra North Shore-LIJ School of Medicine were collected. Repeat FNA and surgical follow-up data were tabulated to establish AUS, secondary AUS (diagnosed upon repeat FNA follow-up of a primary FNA AUS diagnosis), atypia of undetermined significance/malignancy (AUS:M) ratios (according to the TBS categories), and malignancy rates for AUS. The AUS rate was 8.5% (976/11,481), and there was follow-up data for 545 cases. The AUS:M ratio was 2.0. Repeat FNA was performed for 281 cases; 57 proceeded to surgical intervention. Repeat FNA reclassified 71.17% of the cases. The malignancy rates for AUS cases proceeding directly to surgery and for those receiving a surgical intervention after a repeat AUS diagnosis were 33.33% and 43.75%, respectively. Repeat FNA resulted in definitive diagnostic reclassification for 67.61% of primary AUS cases and reduced the number of patients triaged to surgery, with 56.58% of the cases recategorized as benign. Cases undergoing surgery after repeat AUS had a higher malignancy rate than those going straight to surgery, and this emphasizes the value of repeat FNA in selecting surgical candidates. In addition, this study highlights the utility of AUS rate monitoring as a quality measure that has contributed to the ability of the Hofstra North Shore-LIJ School of Medicine to adhere closely to TBS recommendations. © 2016 American Cancer Society.

  18. The effects of repeated-sprint training on field-based fitness measures: a meta-analysis of controlled and non-controlled trials.

    Science.gov (United States)

    Taylor, Jonathan; Macpherson, Tom; Spears, Iain; Weston, Matthew

    2015-06-01

    Repeated-sprint training appears to be an efficient and practical means for the simultaneous development of different components of fitness relevant to team sports. Our objective was to systematically review the literature and meta-analyse the effect of repeated-sprint training on a selection of field-based measures of athletic performance, i.e. counter-movement jump, 10 m sprint, 20 m sprint, 30 m sprint, repeated-sprint ability and high-intensity intermittent running performance. The SPORTDiscus, PubMed, MEDLINE and Web of Science databases were searched for original research articles. Search terms included 'repeated-sprint training', 'sprint training', 'aerobic endurance', 'repeated-sprint ability', 'counter-movement jump' and 'sprint performance'. Inclusion criteria included intervention consisting of a series of ≤10 s sprints with ≤60 s recovery; trained participants; intervention duration of 2-12 weeks; field-based fitness measures; running- or cycling-based intervention; published up to, and including, February 2014. Our final dataset included six trials for counter-movement jump (two controlled trials), eight trials for 10 m sprint, four trials for 20 m sprint (three controlled trials), two trials for 30 m sprint, eight trials for repeated-sprint ability and three trials for high-intensity intermittent running performance. Analyses were conducted using comprehensive meta-analysis software. Uncertainty in the meta-analysed effect of repeated-sprint training was expressed as 95% confidence limits (CL), along with the probability that the true value of the effect was trivial, beneficial or harmful. Magnitude-based inferences were based on standardised thresholds for small, moderate and large changes of 0.2, 0.6 and 1.2 standard deviations, respectively. Repeated-sprint training had a likely small beneficial effect in non-controlled counter-movement jump trials (effect size 0.33; 95% CL ±0.30), with a possibly moderate beneficial effect in controlled

  19. Effects of repeatability measures on results of fMRI sICA: a study on simulated and real resting-state effects.

    Science.gov (United States)

    Remes, Jukka J; Starck, Tuomo; Nikkinen, Juha; Ollila, Esa; Beckmann, Christian F; Tervonen, Osmo; Kiviniemi, Vesa; Silven, Olli

    2011-05-15

    Spatial independent components analysis (sICA) has become a widely applied data-driven method for fMRI data, especially for resting-state studies. These sICA approaches are often based on iterative estimation algorithms and there are concerns about accuracy due to noise. Repeatability measures such as ICASSO, RAICAR and ARABICA have been introduced as remedies but information on their effects on estimates is limited. The contribution of this study was to provide more of such information and test if the repeatability analyses are necessary. We compared FastICA-based ordinary and repeatability approaches concerning mixing vector estimates. Comparisons included original FastICA, FSL4 Melodic FastICA and original and modified ICASSO. The effects of bootstrapping and convergence threshold were evaluated. The results show that there is only moderate improvement due to repeatability measures and only in the bootstrapping case. Bootstrapping attenuated power from time courses of resting-state network related ICs at frequencies higher than 0.1 Hz and made subsets of low frequency oscillations more emphasized IC-wise. The convergence threshold did not have a significant role concerning the accuracy of estimates. The performance results suggest that repeatability measures or strict converge criteria might not be needed in sICA analyses of fMRI data. Consequently, the results in existing sICA fMRI literature are probably valid in this sense. A decreased accuracy of original bootstrapping ICASSO was observed and corrected by using centrotype mixing estimates but the results warrant for thorough evaluations of data-driven methods in general. Also, given the fMRI-specific considerations, further development of sICA methods is strongly encouraged. Copyright © 2010 Elsevier Inc. All rights reserved.

  20. Half-Year Retest-Reliability of the Barratt Impulsiveness Scale–Short Form (BIS-15

    Directory of Open Access Journals (Sweden)

    Adrian Meule

    2015-03-01

    Full Text Available One of the most widely used instruments for the measurement of impulsivity is the Barratt Impulsiveness Scale (BIS-11. The short form of the BIS-11, the BIS-15, consists of 15 items representing the three subscales Attentional, Motor, and Non-Planning Impulsivity. In the current study, retest-reliabilities of BIS-15 scores were examined. Female university students completed the BIS-15 at the beginning of the first (n = 133 and second (n = 120 semesters. Half-year retest-reliability was rtt = .79 for the BIS-15 total score and ranged between rtt = .61 and .78 for the subscales. Considering the long time span of almost half a year between measurements, the total score of the BIS-15 has high retest-reliability and, thus, measures impulsivity as a stable personality trait.

  1. Deployment Repeatability

    Science.gov (United States)

    2016-04-01

    controlled to great precision, but in a Cubesat , there may be no attitude determination at all. Such a Cubesat might treat sun angle and tumbling rates as...could be sensitive to small differences in motor controller timing. In these cases, the analyst might choose to model the entire deployment path, with...knowledge of the material damage model or motor controller timing precision. On the other hand, if many repeated and environmentally representative

  2. Analyzing repeated data collected by mobile phones and frequent text messages. An example of Low back pain measured weekly for 18 weeks

    Directory of Open Access Journals (Sweden)

    Axén Iben

    2012-07-01

    Full Text Available Abstract Background Repeated data collection is desirable when monitoring fluctuating conditions. Mobile phones can be used to gather such data from large groups of respondents by sending and receiving frequently repeated short questions and answers as text messages. The analysis of repeated data involves some challenges. Vital issues to consider are the within-subject correlation, the between measurement occasion correlation and the presence of missing values. The overall aim of this commentary is to describe different methods of analyzing repeated data. It is meant to give an overview for the clinical researcher in order for complex outcome measures to be interpreted in a clinically meaningful way. Methods A model data set was formed using data from two clinical studies, where patients with low back pain were followed with weekly text messages for 18 weeks. Different research questions and analytic approaches were illustrated and discussed, as well as the handling of missing data. In the applications the weekly outcome “number of days with pain” was analyzed in relation to the patients’ “previous duration of pain” (categorized as more or less than 30 days in the previous year. Research questions with appropriate analytical methods 1: How many days with pain do patients experience? This question was answered with data summaries. 2: What is the proportion of participants “recovered” at a specific time point? This question was answered using logistic regression analysis. 3: What is the time to recovery? This question was answered using survival analysis, illustrated in Kaplan-Meier curves, Proportional Hazard regression analyses and spline regression analyses. 4: How is the repeatedly measured data associated with baseline (predictor variables? This question was answered using generalized Estimating Equations, Poisson regression and Mixed linear models analyses. 5: Are there subgroups of patients with similar courses of pain

  3. Repeatability and Reproducibility of Retinal Neuronal and Axonal Measures on Spectral-Domain Optical Coherence Tomography in Patients with Cognitive Impairment

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    Edwin Hong-Teck Loh

    2017-08-01

    Full Text Available BackgroundWith increasing interest in determining if measurement of retinal neuronal structure with spectral-domain optical coherence tomography (SD-OCT is useful in accessing neurodegenerative process in cognitive decline and development of dementia, it is important to evaluate whether the SD-OCT measurements are repeatable and reproducible in these patients.MethodsThis is a retrospective cohort study. Patients with Alzheimer’s disease (AD or mild cognitive impairment (MCI with no change in global clinical dementia rating (CDR score at 1-year follow-up were eligible to be included. Ganglion cell-inner plexiform layer (GC-IPL and retinal nerve fiber layer (RNFL parameters were measured with SD-OCT at baseline, 6-month, and 1-year follow-up visits. At baseline, SD-OCT scans were repeated to access intra-visit repeatability of the SD-OCT measurement. SD-OCT measurement over three visits was used to access inter-visit reproducibility. We calculated intraclass correlation coefficients (ICC and coefficients of variation (CoVs.ResultsWe included 32 patients with stable AD and 29 patients with stable MCI in the final analysis. For GC-IPL measures, the average intra-visit ICC was 0.969 (range: 0.948–0.985, and CoV was 1.81% (range: 1.14–2.40; while the average inter-visit ICC was 0.968 (0.941–0.985, and CoV was 1.91% (range: 1.24–2.32. The average ICC and CoV of intra-visit RNFL measured were 0.965 (range: 0.937–0.986 and 2.32% (range: 1.34–2.90%, respectively. The average ICC and CoV of inter-visit RNFL measures were 0.927 (range: 0.845–0.961 and 3.83% (range: 2.71–5.25%, respectively.ConclusionBoth GC-IPL and RNFL measurements had good intra-visit repeatability and inter-visit reproducibility over 1 year in elderly patients with no decline in cognitive function, suggesting that SD-OCT is a reliable tool to assess neurodegenerative process over time.

  4. Repeatability and Reproducibility of Retinal Nerve Fiber Layer Parameters Measured by Scanning Laser Polarimetry with Enhanced Corneal Compensation in Normal and Glaucomatous Eyes

    Directory of Open Access Journals (Sweden)

    Mirian Ara

    2015-01-01

    Full Text Available Objective. To assess the intrasession repeatability and intersession reproducibility of peripapillary retinal nerve fiber layer (RNFL thickness parameters measured by scanning laser polarimetry (SLP with enhanced corneal compensation (ECC in healthy and glaucomatous eyes. Methods. One randomly selected eye of 82 healthy individuals and 60 glaucoma subjects was evaluated. Three scans were acquired during the first visit to evaluate intravisit repeatability. A different operator obtained two additional scans within 2 months after the first session to determine intervisit reproducibility. The intraclass correlation coefficient (ICC, coefficient of variation (COV, and test-retest variability (TRT were calculated for all SLP parameters in both groups. Results. ICCs ranged from 0.920 to 0.982 for intravisit measurements and from 0.910 to 0.978 for intervisit measurements. The temporal-superior-nasal-inferior-temporal (TSNIT average was the highest (0.967 and 0.946 in normal eyes, while nerve fiber indicator (NFI; 0.982 and inferior average (0.978 yielded the best ICC in glaucomatous eyes for intravisit and intervisit measurements, respectively. All COVs were under 10% in both groups, except NFI. TSNIT average had the lowest COV (2.43% in either type of measurement. Intervisit TRT ranged from 6.48 to 12.84. Conclusions. The reproducibility of peripapillary RNFL measurements obtained with SLP-ECC was excellent, indicating that SLP-ECC is sufficiently accurate for monitoring glaucoma progression.

  5. Repeatability and Reproducibility of Retinal Nerve Fiber Layer Parameters Measured by Scanning Laser Polarimetry with Enhanced Corneal Compensation in Normal and Glaucomatous Eyes.

    Science.gov (United States)

    Ara, Mirian; Ferreras, Antonio; Pajarin, Ana B; Calvo, Pilar; Figus, Michele; Frezzotti, Paolo

    2015-01-01

    To assess the intrasession repeatability and intersession reproducibility of peripapillary retinal nerve fiber layer (RNFL) thickness parameters measured by scanning laser polarimetry (SLP) with enhanced corneal compensation (ECC) in healthy and glaucomatous eyes. One randomly selected eye of 82 healthy individuals and 60 glaucoma subjects was evaluated. Three scans were acquired during the first visit to evaluate intravisit repeatability. A different operator obtained two additional scans within 2 months after the first session to determine intervisit reproducibility. The intraclass correlation coefficient (ICC), coefficient of variation (COV), and test-retest variability (TRT) were calculated for all SLP parameters in both groups. ICCs ranged from 0.920 to 0.982 for intravisit measurements and from 0.910 to 0.978 for intervisit measurements. The temporal-superior-nasal-inferior-temporal (TSNIT) average was the highest (0.967 and 0.946) in normal eyes, while nerve fiber indicator (NFI; 0.982) and inferior average (0.978) yielded the best ICC in glaucomatous eyes for intravisit and intervisit measurements, respectively. All COVs were under 10% in both groups, except NFI. TSNIT average had the lowest COV (2.43%) in either type of measurement. Intervisit TRT ranged from 6.48 to 12.84. The reproducibility of peripapillary RNFL measurements obtained with SLP-ECC was excellent, indicating that SLP-ECC is sufficiently accurate for monitoring glaucoma progression.

  6. Repeatability of Brain Volume Measurements Made with the Atlas-based Method from T1-weighted Images Acquired Using a 0.4 Tesla Low Field MR Scanner.

    Science.gov (United States)

    Goto, Masami; Suzuki, Makoto; Mizukami, Shinya; Abe, Osamu; Aoki, Shigeki; Miyati, Tosiaki; Fukuda, Michinari; Gomi, Tsutomu; Takeda, Tohoru

    2016-10-11

    An understanding of the repeatability of measured results is important for both the atlas-based and voxel-based morphometry (VBM) methods of magnetic resonance (MR) brain volumetry. However, many recent studies that have investigated the repeatability of brain volume measurements have been performed using static magnetic fields of 1-4 tesla, and no study has used a low-strength static magnetic field. The aim of this study was to investigate the repeatability of measured volumes using the atlas-based method and a low-strength static magnetic field (0.4 tesla). Ten healthy volunteers participated in this study. Using a 0.4 tesla magnetic resonance imaging (MRI) scanner and a quadrature head coil, three-dimensional T1-weighted images (3D-T1WIs) were obtained from each subject, twice on the same day. VBM8 software was used to construct segmented normalized images [gray matter (GM), white matter (WM), and cerebrospinal fluid (CSF) images]. The regions-of-interest (ROIs) of GM, WM, CSF, hippocampus (HC), orbital gyrus (OG), and cerebellum posterior lobe (CPL) were generated using WFU PickAtlas. The percentage change was defined as[100 × (measured volume with first segmented image - mean volume in each subject)/(mean volume in each subject)]The average percentage change was calculated as the percentage change in the 6 ROIs of the 10 subjects. The mean of the average percentage changes for each ROI was as follows: GM, 0.556%; WM, 0.324%; CSF, 0.573%; HC, 0.645%; OG, 1.74%; and CPL, 0.471%. The average percentage change was higher for the orbital gyrus than for the other ROIs. We consider that repeatability of the atlas-based method is similar between 0.4 and 1.5 tesla MR scanners. To our knowledge, this is the first report to show that the level of repeatability with a 0.4 tesla MR scanner is adequate for the estimation of brain volume change by the atlas-based method.

  7. Bipolar resistive switching based on bis(8-hydroxyquinoline)cadmium complex: Mechanism and non-volatile memory application

    Institute of Scientific and Technical Information of China (English)

    Wang Ying; Yang Ting; Xie Ji-Peng; Lü Wen-Li; Fan Guo-Ying; Liu Su

    2013-01-01

    Stable and persistent bipolar resistive switching was observed in an organic diode with the structure of indium-tin oxide (ITO)/bis(8-hydroxyquinoline) cadmium (Cdq2)/Al.Aggregate formation and electric field driven trapping and detrapping of charge carriers in the aggregate states that lie in the energy gap of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) of the organic molecule were proposed as the mechanism of the observed bipolar resistive switching,and this was solidly supported by the results of AFM investigations.Repeatedly set,read,and reset measurements demonstrated that the device is potentially applicable in non-volatile memories.

  8. Fixed-flexion knee radiography using a new positioning device produced highly repeatable measurements of joint space width: ELSA-Brasil Musculoskeletal Study (ELSA-Brasil MSK).

    Science.gov (United States)

    Telles, Rosa Weiss; Costa-Silva, Luciana; Machado, Luciana A C; Reis, Rodrigo Citton Padilha Dos; Barreto, Sandhi Maria

    To describe the performance of a non-fluoroscopic fixed-flexion PA radiographic protocol with a new positioning device, developed for the assessment of knee osteoarthritis (OA) in Brazilian Longitudinal Study of Adult Health Musculoskeletal Study (ELSA-Brasil MSK). A test-retest design including 19 adults (38 knee images) was conducted. Feasibility of the radiographic protocol was assessed by image quality parameters and presence of radioanatomic alignment according to intermargin distance (IMD) values. Repeatability was assessed for IMD and joint space width (JSW) measured at three different locations. Approximately 90% of knee images presented excellent quality. Frequencies of nearly perfect radioanatomic alignment (IMD ≤1mm) ranged from 29% to 50%, and satisfactory alignment was found in up to 71% and 76% of the images (IMD ≤1.5mm and ≤1.7mm, respectively). Repeatability analyses yielded the following results: IMD [SD of mean difference=1.08; coefficient of variation (%CV)=54.68%; intraclass correlation coefficient (ICC) (95%CI)=0.59 (0.34-0.77)]; JSW [SD of mean difference=0.34-0.61; %CV=4.48%-9.80%; ICC (95%CI)=0.74 (0.55-0.85)-0.94 (0.87-0.97)]. Adequately reproducible measurements of IMD and JSW were found in 68% and 87% of the images, respectively. Despite the difficulty in achieving consistent radioanatomic alignment between subsequent radiographs in terms of IMD, the protocol produced highly repeatable JSW measurements when these were taken at midpoint and 10mm from the medial extremity of the medial tibial plateau. Therefore, measurements of JSW at these locations can be considered adequate for the assessment of knee OA in ELSA-Brasil MSK. Copyright © 2016. Published by Elsevier Editora Ltda.

  9. Repeated-Sprint Cycling Does Not Induce Respiratory Muscle Fatigue in Active Adults: Measurements from The Powerbreathe® Inspiratory Muscle Trainer

    Directory of Open Access Journals (Sweden)

    Clare Minahan, Beth Sheehan, Rachel Doutreband, Tom Kirkwood, Daniel Reeves, Troy Cross

    2015-03-01

    Full Text Available This study examined respiratory muscle strength using the POWERbreathe® inspiratory muscle trainer (i.e., ‘S-Index’ before and after repeated-sprint cycling for comparison with maximal inspiratory pressure (MIP values obtained during a Mueller maneuver. The S-Index was measured during six trials across two sessions using the POWERbreathe® and MIP was measured during three trials in a single session using a custom-made manometer in seven recreationally active adults. Global respiratory muscle strength was measured using both devices before and after the performance of sixteen, 6-s sprints on a cycle ergometer. Intraclass correlation coefficients for the POWERbreathe® S-index indicated excellent (p 0.99 and during the Mueller maneuver (p > 0.99. The POWERbreathe® S-Index is a moderately reliable, but not equivalent, measure of MIP determined during a Mueller maneuver. Furthermore, repeated-sprint cycling does not induce globalized respiratory muscle fatigue in recreationally-active adults.

  10. Repeatability of measurements of packed cell volume and egg count as indicators of endoparasite load and their relationship with sheep productivity.

    Science.gov (United States)

    Bekele, T; Kasali, O B; Rege, J E

    1991-12-01

    Monthly measurements of packed cell volume (PCV) and nematode and trematode eggs per gram (EPG) were made in Ethiopian highland sheep at Debre Berhan, Dejen, Deneba, Tulu Meko and Wereilu from June 1988 to December 1989. High frequencies of low PCV, high nematode EPG and high trematode EPG were found at Tulu Meko. Among the productivity traits examined, body condition scores and live-weights were significantly (P less than 0.05) associated with differences in PCV and nematode and trematode EPG levels at most sites. The lambing interval was, however, not significantly (P greater than 0.05) affected by these variables. Monthly repeatabilities of PCV, body weight and body condition scores were 0.44 +/- 0.01, 0.71 +/- 0.01 and 0.35 +/- 0.01, respectively, while those of nematode (0.09 +/- 0.01) and trematode EPGs (0.20 +/- 0.02) were much lower. The high repeatability for PCV indicates that it was less affected by the variable factors influencing egg output, and hence it could be utilized in conjunction with nematode and trematode EPG levels for endoparasite monitoring. Repeatability of the lambing interval across parities was 0.43 +/- 0.14.

  11. Relationship between measures of aerobic fitness, speed and repeated sprint ability in full and part time youth soccer players.

    Science.gov (United States)

    Gibson, N; Currie, J; Johnston, R; Hill, J

    2013-02-01

    The aim of the study was to investigate the relationship between repeated sprint ability (RSA) involving changes in direction, short linear sprinting and aerobic capacity in young elite soccer players. A secondary aim was to assess any differences in performance of these assessments between players of different age groups. Thirty-two male adolescent soccer players belonging to the same elite club academy were assessed for RSA comprising 6 x 40m efforts interspersed by 25s recovery, linear sprinting speed over 15m, and aerobic capacity via the YYIE2 assessment. There was a significant correlation between performance in the YYIE2 and RSA total time, RSA fastest sprint and RSA percentage decrement (r = -0.71, -0.53, and -0.52 respectively. Psprint (Psprinting. Assessments of RSA over 40m and incorporating changes of direction appear to be significantly correlated with YYIE2 performance in young elite level soccer players. In addition older players performed significantly better in the YYIE2 assessment and RSA protocol but not in short linear sprinting. These results have implications for the design of assessment protocols for young elite soccer players of different ages.

  12. Very long Detection Times after High and repeated intake of Heroin and Methadone, measured in Oral Fluid

    Directory of Open Access Journals (Sweden)

    Vindenes V.

    2014-12-01

    Full Text Available When detection times for psychoactive drugs in oral fluid are reported, they are most often based on therapeutic doses administered in clinical studies. Repeated ingestions of high doses, as seen after drug abuse, are however likely to cause positive samples for extended time periods. Findings of drugs of abuse in oral fluid might lead to negative sanctions, and the knowledge of detection times of these drugs are important to ensure correct interpretation. The aim of this study was to investigate the detection times of opioids in oral fluid. 25 patients with a history of heavy drug abuse admitted to a detoxification ward were included. Oral fluid and urine were collected daily and, if the patient gave consent, a blood sample was drawn during the first five days after admission. Morphine, codeine and/or 6-monoacetyl morphine (6-MAM were found in oral fluid and/or urine from 20 patients. The maximum detection times in oral fluid for codeine, morphine and 6-MAM were 1, 3 and 8 days, respectively. Positive oral fluid samples were interspersed with negative samples, mainly for concentrations around cut off. Elimination curves for methadone in oral fluid were found for two subjects, and the detection times were 5 and 8 days. Oral fluid is likely to become a good method for detection of drug abuse in the future

  13. The reliability of repeated TMS measures in older adults and in patients with subacute and chronic stroke

    Directory of Open Access Journals (Sweden)

    Heidi M. Schambra

    2015-09-01

    Full Text Available The reliability of transcranial magnetic stimulation (TMS measures in healthy older adults and stroke patients has been insufficiently characterized. We determined whether common TMS measures could reliably evaluate change in individuals and in groups using the smallest detectable change (SDC, or could tell subjects apart using the intraclass correlation coefficient (ICC. We used a single-rater test-retest design in older healthy, subacute stroke, and chronic stroke subjects. At twice daily sessions on two consecutive days, we recorded resting motor threshold, test stimulus intensity, recruitment curves, short-interval intracortical inhibition and facilitation, and long-interval intracortical inhibition. Using variances estimated from a random effects model, we calculated the SDC and ICC for each TMS measure. For all TMS measures in all groups, SDCs for single subjects were large; only with modest group sizes did the SDCs become low. Thus, while these TMS measures cannot be reliably used as a biomarker to detect individual change, they can reliably detect change exceeding measurement noise in moderate-sized groups. For several of the TMS measures, ICCs were universally high, suggesting that they can reliably discriminate between subjects. Though most TMS measures have sufficient reliability in particular contexts, work establishing their validity, responsiveness, and clinical relevance is still needed.

  14. Comparison of intraclass correlation coefficient estimates and standard errors between using cross-sectional and repeated measurement data: the Safety Check cluster randomized trial.

    Science.gov (United States)

    Ip, Edward H; Wasserman, Richard; Barkin, Shari

    2011-03-01

    Designing cluster randomized trials in clinical studies often requires accurate estimates of intraclass correlation, which quantifies the strength of correlation between units, such as participants, within a cluster, such as a practice. Published ICC estimates, even when available, often suffer from the problem of wide confidence intervals. Using data from a national, randomized, controlled study concerning violence prevention for children--the Safety Check--we compare the ICC values derived from two approaches only baseline data and using both baseline and follow-up data. Using a variance component decomposition approach, the latter method allows flexibility in handling complex data sets. For example, it allows for shifts in the outcome variable over time and for an unbalanced cluster design. Furthermore, we evaluate the large-sample formula for ICC estimates and standard errors using the bootstrap method. Our findings suggest that ICC estimates range from 0.012 to 0.11 for providers within practice and range from 0.018 to 0.11 for families within provider. The estimates derived from the baseline-only and repeated-measurements approaches agree quite well except in cases in which variation over repeated measurements is large. The reductions in the widths of ICC confidence limits from using repeated measurement over baseline only are, respectively, 62% and 42% at the practice and provider levels. The contribution of this paper therefore includes two elements, which are a methodology for improving the accuracy of ICC, and the reporting of such quantities for pediatric and other researchers who are interested in designing clustered randomized trials similar to the current study.

  15. Air quality in Nordrhein-Westfalen: Mobile pollutant measurements at Guetersloh. December 1999 through February 2000; Luftqualitaet in Nordrhein-Westfalen: Mobile Immissionsmessung Guetersloh. Dezember 1999 bis Februar 2000

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    Between December 1999 and February 2000, a MILIS monitoring project was carried out at Guetersloh on behalf of the Guetersloh Environmental Protection Office. Airborne dust, PCB, dioxins and furans, PAH and VOC were recorded. Apart from a non-analyzeable concentration of {alpha} pinene, no significant pollution levels were recorded although the measuring probes were located in sites with inner city conditions. [German] Von Dezember 1999 bis Februar 2000 wurde in Guetersloh eine MILIS-Messung durchgefuehrt. Die Messung wurde vom Amt fuer Umweltschutz der Stadt Guetersloh beantragt. Der Schwerpunkt der MILIS-Messung lag in der Bestimmung der Schwebstaubkonzentration, der Analyse der polychlorierten Biphenyle, der Dioxine und Furane, der polycyclischen aromatischen Kohlenwasserstoffe sowie der leichtfluechtigen organischen Verbindungen. Die Ergebnisse der MILIS-Messung in Guetersloh ergaben, ausser einer nicht weiter bewertbaren {alpha}-Pinen-Konzentration, keinen Hinweis auf aussergewoehnliche Belastungen. Die am Messstandort ermittelten Immissionskonzentrationen liegen in Bereichen, die an innerstaedtischen Standorten zu erwarten sind. (orig.)

  16. Analysis of carrier transport and carrier trapping in organic diodes with polyimide-6,13-Bis(triisopropylsilylethynyl)pentacene double-layer by charge modulation spectroscopy and optical second harmonic generation measurement

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Eunju, E-mail: elim@dankook.ac.kr, E-mail: taguchi.d.aa@m.titech.ac.jp, E-mail: iwamoto@pe.titech.ac.jp [Department of Applied Physics, Institute of Nanosensor and Biotechnology, Dankook University, Jukjeon-dong, Gyeonggi-do 448-701 (Korea, Republic of); Taguchi, Dai, E-mail: elim@dankook.ac.kr, E-mail: taguchi.d.aa@m.titech.ac.jp, E-mail: iwamoto@pe.titech.ac.jp; Iwamoto, Mitsumasa, E-mail: elim@dankook.ac.kr, E-mail: taguchi.d.aa@m.titech.ac.jp, E-mail: iwamoto@pe.titech.ac.jp [Department of Physical Electronics, Tokyo Institute of Technology 2-12-1, O-okayama, Meguro-ku, Tokyo 152-8552 (Japan)

    2014-08-18

    We studied the carrier transport and carrier trapping in indium tin oxide/polyimide (PI)/6,13-Bis(triisopropylsilylethynyl)pentacene (TIPS-pentacene)/Au diodes by using charge modulation spectroscopy (CMS) and time-resolved electric field induced optical second harmonic generation (TR-EFISHG) measurements. TR-EFISHG directly probes the spatial carrier behaviors in the diodes, and CMS is useful in explaining the carrier motion with respect to energy. The results clearly indicate that the injected carriers move across TIPS-pentacene thorough the molecular energy states of TIPS-pentacene and accumulate at the PI/TIPS-pentacene interface. However, some carriers are trapped in the PI layers. These findings take into account the capacitance-voltage and current-voltage characteristics of the diodes.

  17. Local structure and intermolecular dynamics of an equimolar benzene and 1,3-dimethylimidazolium bis[(trifluoromethane)sulfonyl]amide mixture: Molecular dynamics simulations and OKE spectroscopic measurements

    Science.gov (United States)

    Lynden-Bell, Ruth M.; Xue, Lianjie; Tamas, George; Quitevis, Edward L.

    2014-07-01

    The local structure and intermolecular dynamics of an equimolar mixture of benzene and 1,3-dimethylimidazolium bis[(trifluoromethane)sulfonyl]amide ([dmim][NTf2]) were studied using molecular dynamics (MD) simulations and femtosecond optical Kerr effect (OKE) spectroscopy. The OKE spectrum of the benzene/[dmim][NTf2] mixture at 295 K was analyzed by comparing it to an ideal mixture spectrum obtained by taking the volume-fraction weighted sum of the OKE spectra of the pure liquids. The experimental mixture spectrum is higher in frequency and broader than that of the ideal mixture spectrum. These spectral differences are rationalized in terms of the local structure around benzene molecules in the mixture and the intermolecular dynamics as reflected in the density of states from the MD simulations. Specifically, we attribute the deviation of the OKE spectrum of the mixture from ideal behavior to benzene molecules seeing a stiffer intermolecular potential due to their being trapped in cages comprised of ions in the first solvation shell.

  18. The near-infrared spectroscopy-derived deoxygenated haemoglobin breaking-point is a repeatable measure that demarcates exercise intensity domains.

    Science.gov (United States)

    Iannetta, Danilo; Qahtani, Ahmad; Mattioni Maturana, Felipe; Murias, Juan Manuel

    2017-09-01

    A breaking-point in the near-infrared spectroscopy (NIRS)-derived deoxygenated haemoglobin ([HHb]) profile towards the end of a ramp incremental (RI) cycling test has been associated to the respiratory compensation point (RCP). Despite the physiological value of this measure, its repeatability remains unknown. The aim was to examine the repeatability of the [HHb] breaking-point ([HHb]BP) and its association to RCP during a RI cycling test. A repeated measures design was performed on 11 males (30.5±8.4 year; 76.5±8.4kg) and 4 females (30.5±5.9 year; 61.9±4.4 Kg). Gas exchange and NIRS [HHb] data were collected during RI tests performed on two different days separated by 48h. The [HHb]BP and the RCP were determined and compared for each trial. The [HHb]BP and the respiratory compensation point (RCP) occurred at the same VO2 in test 1 and test 2 ([HHb]BP: 3.49±0.52Lmin(-1) test 1; 3.48±0.45Lmin(-1) test 2; RCP: 3.38±0.40Lmin(-1) test 1; 3.38±0.44Lmin(-1) test 2) (P>0.05). The VO2 associated with the [HHb]BP and the VO2 at RCP were not significantly different from each other either in test 1 as well as in test 2 (P>0.05). Neither test 1 nor test 2 showed significant mean average error between the VO2 at the [HHb]BP and RCP using Bland & Altman plots. The [HHb]BP is a repeatable measure that consistently occurs towards the end of a RI test. The association between the [HHb]BP and the RCP reinforces the idea that these parameters may share similar mechanistic basis. Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  19. Polycarbonate modified with crystallisable bis-ester tetra-amide units in a reaction extrusion process

    NARCIS (Netherlands)

    Zuiderduin, W.C.J.; Gaymans, R.J.

    2008-01-01

    Dry blends of polycarbonate (PC) and a bis-ester tetra-amide were extruded at 305 °C with a mini twin screw extruder. The bis-ester tetra-amide diamide (T6T6T-dimethyl) was composed of two and a half repeat units of Nylon 6,T and had methyl ester endgroups. During the extrusion, a trans-esterificati

  20. Variation in repeated mouth-opening measurements in head and neck cancer patients with and without trismus

    NARCIS (Netherlands)

    Jager-Wittenaar, H.; Dijkstra, P. U.; Vissink, A.; van Oort, R. P.; Roodenburg, J. L. N.

    2009-01-01

    Trismus after head and neck cancer treatment may severely limit mandibular functioning. Interventions aimed at reducing trismus can only be evaluated when the amount of variation associated with these measurements is known. The aim of this Study was to analyse the variation in mouth-opening measurem

  1. Repeated measurements of mite and pet allergen levels in house dust over a time period of 8 years

    NARCIS (Netherlands)

    Antens, C. J. M.; Oldenwening, M.; Wolse, A.; Gehring, U.; Smit, H. A.; Aalberse, R. C.; Kerkhof, M.; Gerritsen, J.; de Jongste, J. C.; Brunekreef, B.

    2006-01-01

    Background Studies of the association between indoor allergen exposure and the development of allergic diseases have often measured allergen exposure at one point in time. Objective We investigated the variability of house dust mite (Der p 1, Der f 1) and cat (Fel d 1) allergen in Dutch homes over a

  2. Variation in repeated mouth-opening measurements in head and neck cancer patients with and without trismus

    NARCIS (Netherlands)

    Jager-Wittenaar, H.; Dijkstra, P. U.; Vissink, A.; van Oort, R. P.; Roodenburg, J. L. N.

    2009-01-01

    Trismus after head and neck cancer treatment may severely limit mandibular functioning. Interventions aimed at reducing trismus can only be evaluated when the amount of variation associated with these measurements is known. The aim of this Study was to analyse the variation in mouth-opening measurem

  3. Variation in repeated mouth-opening measurements in head and neck cancer patients with and without trismus

    NARCIS (Netherlands)

    Jager-Wittenaar, H.; Dijkstra, P. U.; Vissink, A.; van Oort, R. P.; Roodenburg, J. L. N.

    Trismus after head and neck cancer treatment may severely limit mandibular functioning. Interventions aimed at reducing trismus can only be evaluated when the amount of variation associated with these measurements is known. The aim of this Study was to analyse the variation in mouth-opening

  4. Repeated measurements of mite and pet allergen levels in house dust over a time period of 8 years

    NARCIS (Netherlands)

    Antens, C. J. M.; Oldenwening, M.; Wolse, A.; Gehring, U.; Smit, H. A.; Aalberse, R. C.; Kerkhof, M.; Gerritsen, J.; de Jongste, J. C.; Brunekreef, B.

    2006-01-01

    Background Studies of the association between indoor allergen exposure and the development of allergic diseases have often measured allergen exposure at one point in time. Objective We investigated the variability of house dust mite (Der p 1, Der f 1) and cat (Fel d 1) allergen in Dutch homes over a

  5. Effects of ambient air pollution on functional status in patients with chronic congestive heart failure: a repeated-measures study

    Directory of Open Access Journals (Sweden)

    Phillips Russell S

    2007-09-01

    Full Text Available Abstract Background Studies using administrative data report a positive association between ambient air pollution and the risk of hospitalization for congestive heart failure (HF. Circulating levels of B-type natriuretic peptide (BNP are directly associated with cardiac hemodynamics and symptom severity in patients with HF and, therefore, serves as a marker of functional status. We tested the hypothesis that BNP levels would be positively associated with short-term changes in ambient pollution levels among 28 patients with chronic stable HF and impaired systolic function. Methods BNP was measured in whole blood at 0, 6, and 12 weeks. We used linear mixed models to evaluate the association between fine particulate matter (PM2.5, carbon monoxide, sulfur dioxide, nitrogen dioxide, ozone, and black carbon and log(BNP. Lags of 0 to 3 days were considered in separate models. We calculated the intraclass correlation coefficient and within-subject coefficient of variation as measures of reproducibility. Results We found no association between any pollutant and measures of BNP at any lag. For example, a 10 μg/m3 increase in PM2.5 was associated with a 0.8% (95% CI: -16.4, 21.5; p = 0.94 increase in BNP on the same day. The within-subject coefficient of variation was 45% on the natural scale and 9% on the log scale. Conclusion These results suggest that serial BNP measurements are unlikely to be useful in a longitudinal study of air pollution-related acute health effects. The magnitude of expected ambient air pollution health effects appears small in relation to the considerable within-person variability in BNP levels in this population.

  6. A technique for conditioning and calibrating force-sensing resistors for repeatable and reliable measurement of compressive force.

    Science.gov (United States)

    Hall, Rick S; Desmoulin, Geoffrey T; Milner, Theodore E

    2008-12-01

    Miniature sensors that could measure forces applied by the fingers and hand without interfering with manual dexterity or range of motion would have considerable practical value in ergonomics and rehabilitation. In this study, techniques have been developed to use inexpensive pressure-sensing resistors (FSRs) to accurately measure compression force. The FSRs are converted from pressure-sensing to force-sensing devices. The effects of nonlinear response properties and dependence on loading history are compensated by signal conditioning and calibration. A fourth-order polynomial relating the applied force to the current voltage output and a linearly weighted sum of prior outputs corrects for sensor hysteresis and drift. It was found that prolonged (>20h) shear force loading caused sensor gain to change by approximately 100%. Shear loading also had the effect of eliminating shear force effects on sensor output, albeit only in the direction of shear loading. By applying prolonged shear loading in two orthogonal directions, the sensors were converted into pure compression sensors. Such preloading of the sensor is, therefore, required prior to calibration. The error in compression force after prolonged shear loading and calibration was consistently industrial design applications where measurements of finger and hand force are needed.

  7. Repeated measures of body mass index and C-reactive protein in relation to all-cause mortality and cardiovascular disease

    DEFF Research Database (Denmark)

    O'Doherty, Mark G; Jørgensen, Torben; Borglykke, Anders

    2014-01-01

    Obesity has been linked with elevated levels of C-reactive protein (CRP), and both have been associated with increased risk of mortality and cardiovascular disease (CVD). Previous studies have used a single 'baseline' measurement and such analyses cannot account for possible changes in these which...... body mass index (BMI) and CRP with all-cause mortality and CVD. Being overweight (≥25-obese (≥30-....79-0.94) and 0.80 (0.72-0.89). A similar relationship was found, but only for overweight in Glostrup, HR (95 % CI) 0.88 (0.76-1.02); and moderately obese in Tromsø, HR (95 % CI) 0.79 (0.62-1.01). Associations were not evident between repeated measures of BMI and CVD. Conversely, increasing CRP concentrations...

  8. Bis(1-adamantylammonium hexafluoridogermanate

    Directory of Open Access Journals (Sweden)

    Liying Cheng

    2008-01-01

    Full Text Available The title compound, (C10H18N2[GeF6], was obtained hydrothermally from an aqueous solution of GeO2, H3BO3, NiCl2, adamantylammonium chloride, butanol and hydrofluoric acid. The structure consists of discrete bis(1-adamantylammonium cations lying on crystallographic mirror planes and hexafluoridogermanate anions disordered about sites of 2/m point symmetry. In the latter, the Ge atom lies on the site of 2/m symmetry, one F atom lies on the mirror plane and two further F atoms are included in general positions with 50% site occupancy. The cations and anions lie in layers with N—H...F hydrogen bonds formed between them.

  9. Duct Leakage Repeatability Testing

    Energy Technology Data Exchange (ETDEWEB)

    Walker, Iain [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sherman, Max [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2014-01-01

    Duct leakage often needs to be measured to demonstrate compliance with requirements or to determine energy or Indoor Air Quality (IAQ) impacts. Testing is often done using standards such as ASTM E1554 (ASTM 2013) or California Title 24 (California Energy Commission 2013 & 2013b), but there are several choices of methods available within the accepted standards. Determining which method to use or not use requires an evaluation of those methods in the context of the particular needs. Three factors that are important considerations are the cost of the measurement, the accuracy of the measurement and the repeatability of the measurement. The purpose of this report is to evaluate the repeatability of the three most significant measurement techniques using data from the literature and recently obtained field data. We will also briefly discuss the first two factors. The main question to be answered by this study is to determine if differences in the repeatability of these tests methods is sufficient to indicate that any of these methods is so poor that it should be excluded from consideration as an allowed procedure in codes and standards.

  10. Repeated-measure validation of craniofacial metrics from three-dimensional surface scans: application to medical genetics

    Science.gov (United States)

    Lauer, Eric A.; Corner, Brian D.; Li, Peng; Beecher, Robert M.; Deutsch, Curtis

    2002-03-01

    Traditionally, medical geneticists have employed visual inspection (anthroposcopy) to clinically evaluate dysmorphology. In the last 20 years, there has been an increasing trend towards quantitative assessment to render diagnosis of anomalies more objective and reliable. These methods have focused on direct anthropometry, using a combination of classical physical anthropology tools and new instruments tailor-made to describe craniofacial morphometry. These methods are painstaking and require that the patient remain still for extended periods of time. Most recently, semiautomated techniques (e.g., structured light scanning) have been developed to capture the geometry of the face in a matter of seconds. In this paper, we establish that direct anthropometry and structured light scanning yield reliable measurements, with remarkably high levels of inter-rater and intra-rater reliability, as well as validity (contrasting the two methods).

  11. 躯体X线测量板的研制和应用%Validation and repeatability of Limb X Film Measuring Plate

    Institute of Scientific and Technical Information of China (English)

    卫小春; 柴旭峰; 许趁心

    2008-01-01

    Objective To study the efficacy and repeatability of the Limb X Film Measuring Plate (LXMP)in clinical x film measurement of lengths and angles of limbs.Methods The LXMP was de- signed and manufactured for testing.Three known points in 9 templates were taken as golden standards.which were to be compared with measuring results of these projected points on the X film for testing efficacy of LXMP.Twenty-one patients with knees osteoarthritis were selected.The lengths and angles of their lower limbs were measured twice with the help of LXMP by an observer at different time intervals for testing in. Tra-observer repeatability.Two observers measured once on films at the same time for testing inter-observer repeatability.The correlation coefficients,mean absolute difierences between the repeated measurements,and error rate were calculated. Results The points on LXMP could be seen clearly on X film.Validation tests showed the differences in angle measurement between golden standards and measuring results for those pro- jeted points on the X film were insignificant.with mean absolute difference being O.10.-0.21,error rate being 0.12%-3.15%and r being close to 1.The differences in length measurement were insignificant ei- ther,with mean absolute differenee being 0.05 cm-0.16 cm.error rate being 0.12%-o.28%and r being close to 1.The intra-observer repeatability test for beth angles and lengths showed that r was close to I.mean absolute diffefences 0.55.and 0.1-0.37cm and error rate 0.3l%-O.97%.while the inter-observer re- peatability test showed that r was close to 1.mean absolute difierences o.39.and0.05-0.13cm and error rate O.16%-O.35%. Conclusion The Limb X Film Measuring Plate Can be used for accurately mcasuring limb lengths and angles with good efficacy and repeatability.%目的 介绍躯体X线测量板的制作方法 ,探讨其有效性、重复性,为临床X线测量提供一套精确、实用、经济的方法 和工具.方法 设计和制作躯体X线

  12. Repeated measurements of cerebral blood flow in the left superior temporal gyrus reveal tonic hyperactivity in patients with auditory verbal hallucinations: A possible trait marker

    Directory of Open Access Journals (Sweden)

    Philipp eHoman

    2013-06-01

    Full Text Available Background: The left superior temporal gyrus (STG has been suggested to play a key role in auditory verbal hallucinations in patients with schizophrenia. Methods: Eleven medicated subjects with schizophrenia and medication-resistant auditory verbal hallucinations and 19 healthy controls underwent perfusion magnetic resonance imaging with arterial spin labeling. Three additional repeated measurements were conducted in the patients. Patients underwent a treatment with transcranial magnetic stimulation (TMS between the first 2 measurements. The main outcome measure was the pooled cerebral blood flow (CBF, which consisted of the regional CBF measurement in the left superior temporal gyrus (STG and the global CBF measurement in the whole brain.Results: Regional CBF in the left STG in patients was significantly higher compared to controls (p < 0.0001 and to the global CBF in patients (p < 0.004 at baseline. Regional CBF in the left STG remained significantly increased compared to the global CBF in patients across time (p < 0.0007, and it remained increased in patients after TMS compared to the baseline CBF in controls (p < 0.0001. After TMS, PANSS (p = 0.003 and PSYRATS (p = 0.01 scores decreased significantly in patients.Conclusions: This study demonstrated tonically increased regional CBF in the left STG in patients with schizophrenia and auditory hallucinations despite a decrease in symptoms after TMS. These findings were consistent with what has previously been termed a trait marker of auditory verbal hallucinations in schizophrenia.

  13. Evaluation of Multiple Imputation in Missing Data Analysis: An Application on Repeated Measurement Data in Animal Science

    Directory of Open Access Journals (Sweden)

    Gazel Ser

    2015-12-01

    Full Text Available The purpose of this study was to evaluate the performance of multiple imputation method in case that missing observation structure is at random and completely at random from the approach of general linear mixed model. The application data of study was consisted of a total 77 heads of Norduz ram lambs at 7 months of age. After slaughtering, pH values measured at five different time points were determined as dependent variable. In addition, hot carcass weight, muscle glycogen level and fasting durations were included as independent variables in the model. In the dependent variable without missing observation, two missing observation structures including Missing Completely at Random (MCAR and Missing at Random (MAR were created by deleting the observations at certain rations (10% and 25%. After that, in data sets that have missing observation structure, complete data sets were obtained using MI (multiple imputation. The results obtained by applying general linear mixed model to the data sets that were completed using MI method were compared to the results regarding complete data. In the mixed model which was applied to the complete data and MI data sets, results whose covariance structures were the same and parameter estimations and standard estimations were rather close to the complete data are obtained. As a result, in this study, it was ensured that reliable information was obtained in mixed model in case of choosing MI as imputation method in missing observation structure and rates of both cases.

  14. Bayesian hierarchical joint modeling of repeatedly measured continuous and ordinal markers of disease severity: Application to Ugandan diabetes data.

    Science.gov (United States)

    Buhule, O D; Wahed, A S; Youk, A O

    2017-08-22

    Modeling of correlated biomarkers jointly has been shown to improve the efficiency of parameter estimates, leading to better clinical decisions. In this paper, we employ a joint modeling approach to a unique diabetes dataset, where blood glucose (continuous) and urine glucose (ordinal) measures of disease severity for diabetes are known to be correlated. The postulated joint model assumes that the outcomes are from distributions that are in the exponential family and hence modeled as multivariate generalized linear mixed effects model associated through correlated and/or shared random effects. The Markov chain Monte Carlo Bayesian approach is used to approximate posterior distribution and draw inference on the parameters. This proposed methodology provides a flexible framework to account for the hierarchical structure of the highly unbalanced data as well as the association between the 2 outcomes. The results indicate improved efficiency of parameter estimates when blood glucose and urine glucose are modeled jointly. Moreover, the simulation studies show that estimates obtained from the joint model are consistently less biased and more efficient than those in the separate models. Copyright © 2017 John Wiley & Sons, Ltd.

  15. Two to five repeated measurements per patient reduced the required sample size considerably in a randomized clinical trial for patients with inflammatory rheumatic diseases

    Directory of Open Access Journals (Sweden)

    Smedslund Geir

    2013-02-01

    Full Text Available Abstract Background Patient reported outcomes are accepted as important outcome measures in rheumatology. The fluctuating symptoms in patients with rheumatic diseases have serious implications for sample size in clinical trials. We estimated the effects of measuring the outcome 1-5 times on the sample size required in a two-armed trial. Findings In a randomized controlled trial that evaluated the effects of a mindfulness-based group intervention for patients with inflammatory arthritis (n=71, the outcome variables Numerical Rating Scales (NRS (pain, fatigue, disease activity, self-care ability, and emotional wellbeing and General Health Questionnaire (GHQ-20 were measured five times before and after the intervention. For each variable we calculated the necessary sample sizes for obtaining 80% power (α=.05 for one up to five measurements. Two, three, and four measures reduced the required sample sizes by 15%, 21%, and 24%, respectively. With three (and five measures, the required sample size per group was reduced from 56 to 39 (32 for the GHQ-20, from 71 to 60 (55 for pain, 96 to 71 (73 for fatigue, 57 to 51 (48 for disease activity, 59 to 44 (45 for self-care, and 47 to 37 (33 for emotional wellbeing. Conclusions Measuring the outcomes five times rather than once reduced the necessary sample size by an average of 27%. When planning a study, researchers should carefully compare the advantages and disadvantages of increasing sample size versus employing three to five repeated measurements in order to obtain the required statistical power.

  16. The Effects of Repeat Testing, Malingering, and Traumatic Brain Injury on Computerized Measures of Visuospatial Memory Span.

    Science.gov (United States)

    Woods, David L; Wyma, John M; Herron, Timothy J; Yund, E W

    2015-01-01

    Spatial span tests (SSTs) such as the Corsi Block Test (CBT) and the SST of the Wechsler Memory Scale are widely used to assess deficits in spatial working memory. We conducted three experiments to evaluate the test-retest reliability and clinical sensitivity of a new computerized spatial span test (C-SST) that incorporates psychophysical methods to improve the precision of spatial span measurement. In Experiment 1, we analyzed C-SST test-retest reliability in 49 participants who underwent three test sessions at weekly intervals. Intraclass correlation coefficients (ICC) were higher for a psychophysically derived mean span (MnS) metric (0.83) than for the maximal span and total correct metrics used in traditional spatial-span tests. Response times (ReTs) also showed high ICCs (0.93) that correlated negatively with MnS scores and correlated positively with response-time latencies from other tests of processing speed. Learning effects were insignificant. Experiment 2 examined the performance of Experiment 1 participants when instructed to feign symptoms of traumatic brain injury (TBI): 57% showed abnormal MnS z-scores. A MnS z-score cutoff of 3.0 correctly classified 36% of simulated malingerers and 91% of the subgroup of 11 control participants with abnormal spans. Malingerers also made more substitution errors than control participants with abnormal spans (sensitivity = 43%, specificity = 91%). In addition, malingerers showed no evidence of ReT slowing, in contrast to significant abnormalities seen on other malingered tests of processing speed. As a result, differences between ReT z-scores and z-scores on other processing speed tests showed very high sensitivity and specificity in distinguishing malingering and control participants with either normal or abnormal spans. Experiment 3 examined C-SST performance in a group of patients with predominantly mild TBI: neither MnS nor ReT z-scores showed significant group-level abnormalities. The C-SST improves the

  17. Teaching renewable energy using online PBL in investigating its effect on behaviour towards energy conservation among Malaysian students: ANOVA repeated measures approach

    Science.gov (United States)

    Nordin, Norfarah; Samsudin, Mohd Ali; Hadi Harun, Abdul

    2017-01-01

    This research aimed to investigate whether online problem based learning (PBL) approach to teach renewable energy topic improves students’ behaviour towards energy conservation. A renewable energy online problem based learning (REePBaL) instruction package was developed based on the theory of constructivism and adaptation of the online learning model. This study employed a single group quasi-experimental design to ascertain the changed in students’ behaviour towards energy conservation after underwent the intervention. The study involved 48 secondary school students in a Malaysian public school. ANOVA Repeated Measure technique was employed in order to compare scores of students’ behaviour towards energy conservation before and after the intervention. Based on the finding, students’ behaviour towards energy conservation improved after the intervention.

  18. The effect of technical replicate (repeats) on Nix Pro Color Sensor™ measurement precision for meat: A case-study on aged beef colour stability.

    Science.gov (United States)

    Holman, Benjamin W B; Collins, Damian; Kilgannon, Ashleigh K; Hopkins, David L

    2017-09-04

    The Nix Pro Colour Sensor™ (NIX) can be potentially used to measure meat colour, but procedural guidelines that assure measurement reproducibility and repeatability (precision) must first be established. Technical replicate number (r) will minimise response variation, measureable as standard error of predicted mean (SEM), and contribute to improved precision. Consequently, we aimed to explore the effects of r on NIX precision when measuring aged beef colour (colorimetrics; L*, a*, b*, hue and chroma values). Each colorimetric SEM declined with increasing r to indicate improved precision and followed a diminishing rate of improvement that allowed us to recommend r=7 for meat colour studies using the NIX. This definition was based on practical limitations and a* variability, as additional r would be required if other colorimetrics or advanced levels of precision are necessary. Beef ageing and display period, holding temperature, loin and sampled portion were also found to contribute to colorimetric variation, but were incorporated within our definition of r. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

  19. Lecture notes on: Electrical theory behind the measurement of body fluids with bioimpedance spectroscopy (BIS):with applications to the measurement device 4200 HYDRA ECF/ICF Bio-Impedance Spectrum Analyzer from Xitron Technologies

    OpenAIRE

    2008-01-01

    Teksten beskriver, hvordan volumen af kropsvæsker kan måles/estimeres med teknikken bio-impedans-spektroskopi (BIS). De første kapitler forudsætter kun lidt eller ingen teknisk/matematisk viden og kan forhåbentlig læses af enhver, som er interesseret i teknikken. Senere kapitler bliver mere tekniske, men indledes med opsummeringer af konklusionerne. Meningen med noterne er at give en forståelse af teknikken, dens forudsætninger og dens begrænsninger. Der tages udgangspunkt i et konkret appara...

  20. Polymerization contraction and conversion of light-curing BisGMA-based methacrylate resins.

    Science.gov (United States)

    Venhoven, B A; de Gee, A J; Davidson, C L

    1993-09-01

    The aim of this study was to investigate the polymerization contraction and the conversion of light-curing methacrylate resins based on bisphenol-A bis(2-hydroxypropyl)methacrylate (BisGMA) diluted with triethylene glycol dimethyacrylate (TEGDMA), methyl methacrylate (MMA), hydroxypropyl methacrylate (HPMA) or (+/-)-2-ethylhexyl methacrylate (EHMA). The contraction measurements were carried out with a linometer, a simple device to determine true linear polymerization contraction of liquid monomers at ambient temperature. The contraction increased with the amount of diluting monomer. The estimated conversion of the BisGMA-TEGDMA, calculated using the contraction, is consistent with literature values. The BisGMA-HPMA mixtures showed high conversions at moderate contraction.

  1. Measurement of Surface Displacement and Deformation of Mass Movements Using Least Squares Matching of Repeat High Resolution Satellite and Aerial Images

    Directory of Open Access Journals (Sweden)

    Misganu Debella-Gilo

    2012-01-01

    Full Text Available Displacement and deformation are fundamental measures of Earth surface mass movements such as glacier flow, rockglacier creep and rockslides. Ground-based methods of monitoring such mass movements can be costly, time consuming and limited in spatial and temporal coverage. Remote sensing techniques, here matching of repeat optical images, are increasingly used to obtain displacement and deformation fields. Strain rates are usually computed in a post-processing step based on the gradients of the measured velocity field. This study explores the potential of automatically and directly computing velocity, rotation and strain rates on Earth surface mass movements simultaneously from the matching positions and the parameters of the geometric transformation models using the least squares matching (LSM approach. The procedures are exemplified using bi-temporal high resolution satellite and aerial images of glacier flow, rockglacier creep and land sliding. The results show that LSM matches the images and computes longitudinal strain rates, transverse strain rates and shear strain rates reliably with mean absolute deviations in the order of 10−4 (one level of significance below the measured values as evaluated on stable grounds. The LSM also improves the accuracy of displacement estimation of the pixel-precision normalized cross-correlation by over 90% under ideal (simulated circumstances and by about 25% for real multi-temporal images of mass movements.

  2. Lumbar spine and pelvic posture between standing and sitting: a radiologic investigation including reliability and repeatability of the lumbar lordosis measure.

    Science.gov (United States)

    De Carvalho, Diana E; Soave, David; Ross, Kim; Callaghan, Jack P

    2010-01-01

    Sitting has been identified as a cause of mechanical low back pain. The purpose of this study was to use plain film x-rays to measure lumbar spine and pelvic posture differences between standing and sitting. Eight male subjects were radiographed standing and sitting in an automobile seat. Measures of lumbar lordosis, intervertebral disk angles, lumbosacral angle, lumbosacral lordosis, and sacral tilt were completed. One-way analysis of variance (alpha = .05) was conducted on the variables stated above. A Bland-Altman analysis was conducted to assess agreement and repeatability of the lumbar lordosis angle using 2 raters. Lumbar lordosis values in standing (average, 63 degrees +/- 15 degrees ) and sacral inclination (average, 43 degrees +/- 10 degrees ) decreased by 43 degrees and 44 degrees , respectively, in sitting. Intervertebral joint angles in sitting underwent substantial flexion (L1/L2-5 degrees [+/-3 degrees ], L2/L3-7 degrees [+/-3 degrees ], L3/L4-8 degrees [+/-3 degrees ], L4/L5-13 degrees [+/-3 degrees ], and L5/S1-4 degrees [+/-10 degrees ]). Measures of lumbar lordosis; intervertebral disk angles between L2/L3, L3/L4, and L4/L5; lumbosacral lordosis; lumbosacral angle; and sacral tilt were significantly decreased between standing and sitting (P posture should be investigated because they may play a role in preventing injury and low back pain. Copyright 2010 National University of Health Sciences. Published by Mosby, Inc. All rights reserved.

  3. 基于同频RF直放站的回波测量方法%Technique of measuring the echo for RF repeaters in single frequency networks

    Institute of Scientific and Technical Information of China (English)

    陈哲; 宋葛

    2011-01-01

    直放站的同频转发模式存在收发天线间互耦的问题,接收天线在接收主基站的信号时,同时接收到直放站发射天线发射的信号,以同频RF直放站调试隔离度为技术背景,提出了同频RF直放站的回波测量方法.该方法利用CAZAC码实现的初估计快速地估计出回波信道的特性,自适应LMS算法的使用可以进一步跟踪信道的变化.通过MATLAB仿真后,在数字硬件平台上用FPGA实现该方法,并用数字电视信号CMMB做为信号源对系统进行了测试,结果说明此种测量方法准确、实用.%The signal transition mode of repeater which works on the same frequency has some troubles on signal coupling between receive and transmit aerials,the signal from transmit aerial may leak out into receive aerial. This paper presents a method of measuring the echo under the context of isolation test for RF repeaters in single frequency networks. The experimental apparatus firstly uses CAZAC code as the method of channel initial estimation, secondly uses LMS arithmetic to track the change of the channel. After the MATLAB simulation realization has been achieved by FPGA on real digital hardware board. The result of test which uses DTV signal (CMMB) as the source proves the function of method achieved accurately.

  4. Repeat, Low Altitude Measurements of Vegetation Status and Biomass Using Manned Aerial and UAS Imagery in a Piñon-Juniper Woodland

    Science.gov (United States)

    Krofcheck, D. J.; Lippitt, C.; Loerch, A.; Litvak, M. E.

    2015-12-01

    Measuring the above ground biomass of vegetation is a critical component of any ecological monitoring campaign. Traditionally, biomass of vegetation was measured with allometric-based approach. However, it is also time-consuming, labor-intensive, and extremely expensive to conduct over large scales and consequently is cost-prohibitive at the landscape scale. Furthermore, in semi-arid ecosystems characterized by vegetation with inconsistent growth morphologies (e.g., piñon-juniper woodlands), even ground-based conventional allometric approaches are often challenging to execute consistently across individuals and through time, increasing the difficulty of the required measurements and consequently the accuracy of the resulting products. To constrain the uncertainty associated with these campaigns, and to expand the extent of our measurement capability, we made repeat measurements of vegetation biomass in a semi-arid piñon-juniper woodland using structure-from-motion (SfM) techniques. We used high-spatial resolution overlapping aerial images and high-accuracy ground control points collected from both manned aircraft and multi-rotor UAS platforms, to generate digital surface model (DSM) for our experimental region. We extracted high-precision canopy volumes from the DSM and compared these to the vegetation allometric data, s to generate high precision canopy volume models. We used these models to predict the drivers of allometric equations for Pinus edulis and Juniperous monosperma (canopy height, diameter at breast height, and root collar diameter). Using this approach, we successfully accounted for the carbon stocks in standing live and standing dead vegetation across a 9 ha region, which contained 12.6 Mg / ha of standing dead biomass, with good agreement to our field plots. Here we present the initial results from an object oriented workflow which aims to automate the biomass estimation process of tree crown delineation and volume calculation, and partition

  5. Gray's reinforcement sensitivity model and child psychopathology: laboratory and questionnaire assessment of the BAS and BIS.

    Science.gov (United States)

    Colder, Craig R; O'Connor, Roisin M

    2004-08-01

    The Behavioral Approach System (BAS) and Behavioral Inhibition System (BIS) are widely studied components of Gray's sensitivity to reinforcement model. There is growing interest in integrating the BAS and BIS into models of risk for psychopathology, however, few measures assess BAS and BIS functioning in children. We adapted a questionnaire measure and reaction time task from adult studies to assess the BAS and BIS in a sample of 9-12 year olds (N = 63; 42% female). A continuous performance task was also administered to assess physiological correlates of the BAS and BIS. Factor analysis supported 3 subdimensions of the BAS (Drive, Reward Responsivity, and Impulsivity/Fun seeking), and one dimension of the BIS (sensitivity to punishment). Results supported the utility of the questionnaire measures and reaction time task as assessments of BAS and BIS functioning. Moreover, these measures were associated with internalizing and externalizing problem behavior as expected. High levels of impulsivity/fun seeking, but not drive or reward responsivity, were associated with high levels of externalizing problems, whereas high levels of sensitivity to punishment were associated with high levels of internalizing behavior problems. The relation between physiological indices and caregiver reports of the BAS, BIS, and problem behavior were complex and not consistent with expectation.

  6. Revised Reinforcement Sensitivity Theory and Laboratory Assessment of BIS and BAS in Children.

    Science.gov (United States)

    Colder, Craig R; Trucco, Elisa M; Lopez, Hector I; Hawk, Larry W; Read, Jennifer P; Lengua, Liliana J; Weiczorek, William F; Eiden, Rina D

    2011-04-01

    There is considerable interest in Gray's reinforcement sensitivity theory. However, few measures of the behavioral approach (BAS) and inhibition systems (BIS) exist for children. Moreover, the theory was substantially revised a decade ago and measurement instruments are still largely based on the old theory. Our aim was to revise questionnaire and laboratory assessments of BIS and BAS for children. Performance on the Point Scoring Reaction Time Task for Children Revised (PSRTT-CR) conformed to theoretical expectations. Caregiver reports of BIS and BAS were associated with corresponding PSRTT-CR indices, suggesting cross-method convergent and discriminant validity. There was convergence with physiological correlates of BAS, but not physiological correlates of BIS. Overall, our revised measures represent promising instruments of children's BIS and BAS.

  7. All-photonic quantum repeaters

    Science.gov (United States)

    Azuma, Koji; Tamaki, Kiyoshi; Lo, Hoi-Kwong

    2015-01-01

    Quantum communication holds promise for unconditionally secure transmission of secret messages and faithful transfer of unknown quantum states. Photons appear to be the medium of choice for quantum communication. Owing to photon losses, robust quantum communication over long lossy channels requires quantum repeaters. It is widely believed that a necessary and highly demanding requirement for quantum repeaters is the existence of matter quantum memories. Here we show that such a requirement is, in fact, unnecessary by introducing the concept of all-photonic quantum repeaters based on flying qubits. In particular, we present a protocol based on photonic cluster-state machine guns and a loss-tolerant measurement equipped with local high-speed active feedforwards. We show that, with such all-photonic quantum repeaters, the communication efficiency scales polynomially with the channel distance. Our result paves a new route towards quantum repeaters with efficient single-photon sources rather than matter quantum memories. PMID:25873153

  8. Seasonal variation in objectively measured physical activity, sedentary time, cardio-respiratory fitness and sleep duration among 8–11 year-old Danish children: a repeated-measures study

    DEFF Research Database (Denmark)

    Hjorth, Mads F.; Chaput, Jean-Philippe; Michaelsen, Kim;

    2013-01-01

    BACKGROUND: Understanding fluctuations in lifestyle indicators is important to identify relevant time periods to intervene in order to promote a healthy lifestyle; however, objective assessment of multiple lifestyle indicators has never been done using a repeated-measures design. The primary aim...... was, therefore, to examine between-season and within-week variation in physical activity, sedentary behaviour, cardio-respiratory fitness and sleep duration among 8–11 year-old children. METHODS: A total of 1021 children from nine Danish schools were invited to participate and 834 accepted. Due...

  9. New panel test facility for thermal conductivity measurements of insulations up to 1650 C; Plattenmessapparatur zur Bestimmung der effektiven Waermeleitfaehigkeit von Daemmstoffen bei Temperaturen bis 1650 C

    Energy Technology Data Exchange (ETDEWEB)

    Wulf, R. [TU Bergakademie Freiberg (Germany). Institut fuer Waermetechnik und Thermodynamik; Gross, U. [Akademie der Wissenschaften zu Leipzig (Germany). Kommision fuer Technikfolgenabschaetzung; DBI-GTI Freiberg (Deutsches Brennstoffinstitut) (Germany); Barth, G. [TU Bergakademie Freiberg (Germany). Lehrstuhl fuer Technische Thermodynamik

    2005-04-01

    The development of insulations for use at extremely high temperatures is a major challenge for thermophysical property measurements. This paper reports about a new steady-state panel test facility which has been designed and constructed at TU Bergakademie Freiberg (Institut fuer Waermetechnik und Thermodynamik) for measuring the effective thermal conductivity of insulations in the temperature range of 500 to 1650 C. The design concept and underlying operating principles, as well as the preparation of specimens and the measuring process are discussed in detail. In addition, the paper represents the results obtained during the trial phase and FEM simulation of the relevant temperature range as a prerequisite to verify the unit's efficiency in meeting the specified constraints. Measurements on alumina fiber mats, which are used as an example, have provided plausible values and agree well with measurement results obtained for identical materials using other test units at lower temperatures. They confirm the functional efficiency of the new test facility at service temperatures of up to 1650 C. (orig.)

  10. Macroeconomic effects of energy political and climate political measures of the years 1995 up to 2011; Gesamtwirtschaftliche Effekte energie- und klimapolitischer Massnahmen der Jahre 1995 bis 2011

    Energy Technology Data Exchange (ETDEWEB)

    Lehr, Ulrike; Lutz, Christian; Ulrich, Philip [Gesellschaft fuer Wirtschaftliche Strukturforschung mbH (GWS), Osnabrueck (Germany)

    2012-10-15

    Actually, the macroeconomic effects of the energy policy turnaround are discussed controversially. The Federal Government started a comprehensive monitoring process in order to accompany the energy policy turnaround. Currently it is too early for a model-supported ex-post acquisition of the effects of the resolutions of the Federal Government in 2010. Often the implementation of the measures began in 2011. Just now no complete results are available. Under this aspect, the authors of the contribution consider the macroeconomic aspects of the measures which were implemented in the areas energy efficiency, renewable energy sources as well as combined heat and power generation in the years between 1995 and 2011.

  11. Personality Correlates of Aggression: Evidence from Measures of the Five-Factor Model, UPPS Model of Impulsivity, and BIS/BAS

    Science.gov (United States)

    Miller, Joshua D.; Zeichner, Amos; Wilson, Lauren F.

    2012-01-01

    Although many studies of personality and aggression focus on multidimensional traits and higher order personality disorders (e.g., psychopathy), lower order, unidimensional traits may provide more precision in identifying specific aspects of personality that relate to aggression. The current study includes a comprehensive measurement of lower…

  12. Evaluation of the running-based anaerobic sprint test as a measure of repeated sprint ability in collegiate-level soccer players.

    Science.gov (United States)

    Keir, Daniel A; Thériault, Francis; Serresse, Olivier

    2013-06-01

    Repeated sprint ability (RSA) refers to an individual's ability to perform maximal sprints of short duration in succession with little recovery between sprints. The running-based anaerobic sprint test (RAST) has been adapted from the Wingate anaerobic test (WAnT) protocol as a tool to assess RSA and anaerobic power. The purpose of this study was to evaluate the relationship between performance variables and physiological responses obtained during the RAST and the WAnT using 8 collegiate-level soccer players. Participants performed a single trial of both the WAnT and the RAST. Breath-by-breath gas exchange was monitored throughout each trial, and blood lactate (BL) measures were recorded postexercise. The oxygen uptake (VO2) profile suggested that the RAST required greater contributions from aerobic metabolism although there was no difference in VO2peak (p < 0.05). Peak BL values were also similar between the RAST and the WAnT (p < 0.05). Neither peak physiological values nor performance variables (peak and mean power) were significantly correlated between protocols. The weak association in physiological responses indicates that different combinations of metabolic contributions exist between protocols, suggesting that individual performances on each test are not related in collegiate soccer players. Further studies on these relationships with players of other competitive levels and team sport athletes are warranted.

  13. Using the American alligator and a repeated-measures design to place constraints on in vivo shoulder joint range of motion in dinosaurs and other fossil archosaurs.

    Science.gov (United States)

    Hutson, Joel D; Hutson, Kelda N

    2013-01-15

    Using the extant phylogenetic bracket of dinosaurs (crocodylians and birds), recent work has reported that elbow joint range of motion (ROM) studies of fossil dinosaur forearms may be providing conservative underestimates of fully fleshed in vivo ROM. As humeral ROM occupies a more central role in forelimb movements, the placement of quantitative constraints on shoulder joint ROM could improve fossil reconstructions. Here, we investigated whether soft tissues affect the more mobile shoulder joint in the same manner in which they affect elbow joint ROM in an extant archosaur. This test involved separately and repeatedly measuring humeral ROM in Alligator mississippiensis as soft tissues were dissected away in stages to bare bone. Our data show that the ROMs of humeral flexion and extension, as well as abduction and adduction, both show a statistically significant increase as flesh is removed, but then decrease when the bones must be physically articulated and moved until they separate from one another and/or visible joint surfaces. A similar ROM pattern is inferred for humeral pronation and supination. All final skeletonized ROMs were less than initial fully fleshed ROMs. These results are consistent with previously reported elbow joint ROM patterns from the extant phylogenetic bracket of dinosaurs. Thus, studies that avoid separation of complementary articular surfaces may be providing fossil shoulder joint ROMs that underestimate in vivo ROM in dinosaurs, as well as other fossil archosaurs.

  14. Knowledge and skill retention of in-service versus preservice nursing professionals following an informal training program in pediatric cardiopulmonary resuscitation: a repeated-measures quasiexperimental study.

    Science.gov (United States)

    Sankar, Jhuma; Vijayakanthi, Nandini; Sankar, M Jeeva; Dubey, Nandkishore

    2013-01-01

    Our objective was to compare the impact of a training program in pediatric cardiopulmonary resuscitation (CPR) on the knowledge and skills of in-service and preservice nurses at prespecified time points. This repeated-measures quasiexperimental study was conducted in the pediatric emergency and ICU of a tertiary care teaching hospital between January and March 2011. We assessed the baseline knowledge and skills of nursing staff (in-service nurses) and final year undergraduate nursing students (preservice nurses) using a validated questionnaire and a skill checklist, respectively. The participants were then trained on pediatric CPR using standard guidelines. The knowledge and skills were reassessed immediately after training and at 6 weeks after training. A total of 74 participants-28 in-service and 46 preservice professionals-were enrolled. At initial assessment, in-service nurses were found to have insignificant higher mean knowledge scores (6.6 versus 5.8, P = 0.08) while the preservice nurses had significantly higher skill scores (6.5 versus 3.2, P nurses performing better in knowledge test (10.5 versus 9.1, P = 0.01) and the preservice nurses performing better in skill test (9.8 versus 7.4, P skills of in-service and preservice nurses in pediatric CPR improved with training. In comparison to preservice nurses, the in-service nurses seemed to retain knowledge better with time than skills.

  15. Direct and accurate measurement of CAG repeat configuration in the ataxin-1 (ATXN-1) gene by "dual-fluorescence labeled PCR-restriction fragment length analysis".

    Science.gov (United States)

    Lin, Jiang X; Ishikawa, Kinya; Sakamoto, Masaki; Tsunemi, Taiji; Ishiguro, Taro; Amino, Takeshi; Toru, Shuta; Kondo, Ikuko; Mizusawa, Hidehiro

    2008-01-01

    Spinocerebellar ataxia type 1 (SCA1; OMIM: #164400) is an autosomal dominant cerebellar ataxia caused by an expansion of CAG repeat, which encodes polyglutamine, in the ataxin-1 (ATXN1) gene. Length of polyglutamine in the ATXN1 protein is the critical determinant of pathogenesis of this disease. Molecular diagnosis of SCA1 is usually undertaken by assessing the length of CAG repeat configuration using primers spanning this configuration. However, this conventional method may potentially lead to misdiagnosis in assessing polyglutamine-encoding CAG repeat length, since CAT interruptions may be present within the CAG repeat configuration, not only in normal controls but also in neurologically symptomatic subjects. We developed a new method for assessing actual CAG repeat numbers not interrupted by CAT sequences. Polymerase chain reaction using a primer pair labeled with two different fluorescences followed by restriction enzyme digestion with SfaNI which recognizes the sequence "GCATC(N)(5)", lengths of actual CAG repeats that encode polyglutamine were directly detected. We named this method "dual fluorescence labeled PCR-restriction fragment length analysis". We found that numbers of actual CAG repeat encoding polyglutamine do not overlap between our cohorts of normal chromosomes (n=385) and SCA1 chromosomes (n=5). We conclude that the present method is a useful way for molecular diagnosis of SCA1.

  16. Simulated Conversations With Virtual Humans to Improve Patient-Provider Communication and Reduce Unnecessary Prescriptions for Antibiotics: A Repeated Measure Pilot Study

    Science.gov (United States)

    2017-01-01

    Background Despite clear evidence that antibiotics do not cure viral infections, the problem of unnecessary prescribing of antibiotics in ambulatory care persists, and in some cases, prescribing patterns have increased. The overuse of antibiotics for treating viral infections has created numerous economic and clinical consequences including increased medical costs due to unnecessary hospitalizations, antibiotic resistance, disruption of gut bacteria, and obesity. Recent research has underscored the importance of collaborative patient-provider communication as a means to reduce the high rates of unnecessary prescriptions for antibiotics. However, most patients and providers do not feel prepared to engage in such challenging conversations. Objectives The aim of this pilot study was to assess the ability of a brief 15-min simulated role-play conversation with virtual humans to serve as a preliminary step to help health care providers and patients practice, and learn how to engage in effective conversations about antibiotics overuse. Methods A total of 69 participants (35 providers and 34 patients) completed the simulation once in one sitting. A pre-post repeated measures design was used to assess changes in patients’ and providers’ self-reported communication behaviors, activation, and preparedness, intention, and confidence to effectively communicate in the patient-provider encounter. Changes in patients’ knowledge and beliefs regarding antibiotic use were also evaluated. Results Patients experienced a short-term positive improvement in beliefs about appropriate antibiotic use for infection (F1,30=14.10, P=.001). Knowledge scores regarding the correct uses of antibiotics improved immediately postsimulation, but decreased at the 1-month follow-up (F1,30=31.16, P.10) Patients with lower levels of activation exhibited positive, short-term benefits in increased intent and confidence to discuss their needs and ask questions in the clinic visit, positive attitudes

  17. Telomere shortening unrelated to smoking, body weight, physical activity, and alcohol intake: 4,576 general population individuals with repeat measurements 10 years apart.

    Directory of Open Access Journals (Sweden)

    Maren Weischer

    2014-03-01

    Full Text Available Cross-sectional studies have associated short telomere length with smoking, body weight, physical activity, and possibly alcohol intake; however, whether these associations are due to confounding is unknown. We tested these hypotheses in 4,576 individuals from the general population cross-sectionally, and with repeat measurement of relative telomere length 10 years apart. We also tested whether change in telomere length is associated with mortality and morbidity in the general population. Relative telomere length was measured with quantitative polymerase chain reaction. Cross-sectionally at the first examination, short telomere length was associated with increased age (P for trend across quartiles = 3 × 10(-77, current smoking (P = 8 × 10(-3, increased body mass index (P = 7 × 10(-14, physical inactivity (P = 4 × 10(-17, but not with increased alcohol intake (P = 0.10. At the second examination 10 years later, 56% of participants had lost and 44% gained telomere length with a mean loss of 193 basepairs. Change in leukocyte telomere length during 10 years was associated inversely with baseline telomere length (P<1 × 10(-300 and age at baseline (P = 1 × 10(-27, but not with baseline or 10-year inter-observational tobacco consumption, body weight, physical activity, or alcohol intake. Prospectively during a further 10 years follow-up after the second examination, quartiles of telomere length change did not associate with risk of all-cause mortality, cancer, chronic obstructive pulmonary disease, diabetes mellitus, ischemic cerebrovascular disease, or ischemic heart disease. In conclusion, smoking, increased body weight, and physical inactivity were associated with short telomere length cross-sectionally, but not with telomere length change during 10 years observation, and alcohol intake was associated with neither. Also, change in telomere length did not associate prospectively with mortality or morbidity in the general population.

  18. Joint modeling of repeated multivariate cognitive measures and competing risks of dementia and death: a latent process and latent class approach.

    Science.gov (United States)

    Proust-Lima, Cécile; Dartigues, Jean-François; Jacqmin-Gadda, Hélène

    2016-02-10

    Joint models initially dedicated to a single longitudinal marker and a single time-to-event need to be extended to account for the rich longitudinal data of cohort studies. Multiple causes of clinical progression are indeed usually observed, and multiple longitudinal markers are collected when the true latent trait of interest is hard to capture (e.g., quality of life, functional dependency, and cognitive level). These multivariate and longitudinal data also usually have nonstandard distributions (discrete, asymmetric, bounded, etc.). We propose a joint model based on a latent process and latent classes to analyze simultaneously such multiple longitudinal markers of different natures, and multiple causes of progression. A latent process model describes the latent trait of interest and links it to the observed longitudinal outcomes using flexible measurement models adapted to different types of data, and a latent class structure links the longitudinal and cause-specific survival models. The joint model is estimated in the maximum likelihood framework. A score test is developed to evaluate the assumption of conditional independence of the longitudinal markers and each cause of progression given the latent classes. In addition, individual dynamic cumulative incidences of each cause of progression based on the repeated marker data are derived. The methodology is validated in a simulation study and applied on real data about cognitive aging obtained from a large population-based study. The aim is to predict the risk of dementia by accounting for the competing death according to the profiles of semantic memory measured by two asymmetric psychometric tests.

  19. Bis[μ-3,5-bis(pyridin-2-ylpyrazolato]bis[(hexafluorophosphatocopper(II

    Directory of Open Access Journals (Sweden)

    Satoshi Kawata

    2013-08-01

    Full Text Available The title dinuclear complex molecule, [Cu2(C13H9N42(PF62], lies about an inversion center. The CuII atom shows a square-pyramidal coordination geometry with the basal plane formed by four N atoms of the two bis-chelating 3,5-bis(pyridin-2-ylpyrazolate ions and with one F atom of the hexafluorophosphate ion in the apical position. Molecules are stacked in a column along the a axis through C—H...F hydrogen bonds. The columns are further linked by other C—H...F hydrogen bonds, forming a three-dimensional network.

  20. [1,2-Bis(diphenylphosphinoethane]{2-[bis(diphenylphosphinomethylamino]pyridinium}fluoridohydrazidatomolybdenum(IV bis(tetrafluoridoborate

    Directory of Open Access Journals (Sweden)

    Felix Tuczek

    2008-05-01

    Full Text Available In the crystal structure of the title compound, [MoF(N2H2(C31H29N2P2(C26H24P2](BF42, each Mo atom is surrounded by four P atoms of one 1,2-bis(diphenylphosphinoethane and one 2-[bis(diphenylphosphinomethylamino]pyridinium ligand. The remaining binding sites of the distorted octahedron are occupied by a hydrazidate (NNH22− and a fluoride ligand. Two F atoms of an anion are disordered over two positions; the site occupancy factors are ca 0.7 and 0.3.

  1. An evaluation of a structured learning program as a component of the clinical practicum in undergraduate nurse education: A repeated measures analysis.

    Science.gov (United States)

    Watt, Elizabeth; Murphy, Maria; MacDonald, Lee; Pascoe, Elizabeth; Storen, Heather; Scanlon, Andrew

    2016-01-01

    There is evidence that nursing students experience stress and anxiety and a reduction in self-efficacy when undertaking clinical placements. Previous reports have identified that a structured three-day program within the Bachelor of Nursing (BN) clinical practicum reduces the students self-report of anxiety and increases self-efficacy. However, it is unreported whether these improved outcomes are sustained for the duration of the clinical placement. The aim of this study was to evaluate the duration of the effect of a three-day structured learning program within the clinical placement on final year Bachelor of Nursing student's report of anxiety and self-efficacy pre- and post-program participation in this intervention and following completion of the clinical practicum. A repeated measures design. University-based Clinical School of Nursing, acute care clinical practicum. Final year Bachelor of Nursing students. The intervention comprised the three-day program on starting the clinical practicum. A questionnaire included the anxiety subscale of The Hospital Anxiety & Depression Scale (The HAD) and the General Self-Efficacy Scale (GSES-12). The questionnaire was completed on day one (time one), upon completion of the three-day program (time two) and upon completion of placement on day 18 (time three). The questionnaire response rate varied over time. There was a statistically significant effect in reducing anxiety over time: F(1.73,74.46)=25.20, plearning program and the benefit of the intervention is sustained for the clinical placement duration. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Which are the most useful scales for predicting repeat self-harm? A systematic review evaluating risk scales using measures of diagnostic accuracy

    Science.gov (United States)

    Quinlivan, L; Cooper, J; Davies, L; Hawton, K; Gunnell, D; Kapur, N

    2016-01-01

    Objectives The aims of this review were to calculate the diagnostic accuracy statistics of risk scales following self-harm and consider which might be the most useful scales in clinical practice. Design Systematic review. Methods We based our search terms on those used in the systematic reviews carried out for the National Institute for Health and Care Excellence self-harm guidelines (2012) and evidence update (2013), and updated the searches through to February 2015 (CINAHL, EMBASE, MEDLINE, and PsychINFO). Methodological quality was assessed and three reviewers extracted data independently. We limited our analysis to cohort studies in adults using the outcome of repeat self-harm or attempted suicide. We calculated diagnostic accuracy statistics including measures of global accuracy. Statistical pooling was not possible due to heterogeneity. Results The eight papers included in the final analysis varied widely according to methodological quality and the content of scales employed. Overall, sensitivity of scales ranged from 6% (95% CI 5% to 6%) to 97% (CI 95% 94% to 98%). The positive predictive value (PPV) ranged from 5% (95% CI 3% to 9%) to 84% (95% CI 80% to 87%). The diagnostic OR ranged from 1.01 (95% CI 0.434 to 2.5) to 16.3 (95%CI 12.5 to 21.4). Scales with high sensitivity tended to have low PPVs. Conclusions It is difficult to be certain which, if any, are the most useful scales for self-harm risk assessment. No scales perform sufficiently well so as to be recommended for routine clinical use. Further robust prospective studies are warranted to evaluate risk scales following an episode of self-harm. Diagnostic accuracy statistics should be considered in relation to the specific service needs, and scales should only be used as an adjunct to assessment. PMID:26873046

  3. Synthesis, spectroscopic properties and theoretical studies of bis-Schiff bases derived from polyamine and pyrazolones.

    Science.gov (United States)

    Ren, Tiegang; Liu, Shuyun; Li, Guihui; Zhang, Jinglai; Guo, Jia; Li, Weijie; Yang, Lirong

    2012-11-01

    A series of novel bis-Schiff base were synthesized from 1-aryl-3-methyl-4-benzoyl-5-pyrazolones and diethylenetriamine (or triethylenetetramine) as the starting materials. All of these bis-Schiff bases were characterized by means of NMR, IR, and MS. The UV-vis absorption spectra and fluorescent spectra of these bis-Schiff bases were also measured. Moreover, the B3LYP/6-31G(d) method was used to optimize the ground state geometry of the bis-Schiff bases; and the UV-vis spectroscopic properties of the products were computed and compared with corresponding experimental data based on cc-pVDZ basis set of TD-B3LYP method. It has been found that all of these bis-Schiff bases show a remarkable absorption peak in a wavelength range of 270-340 nm; and their maximum emission peaks are around 348 nm.

  4. Comparison of non-electrophoresis grade with electrophoresis grade BIS in NIPAM polymer gel preparation.

    Science.gov (United States)

    Khodadadi, Roghayeh; Khajeali, Azim; Farajollahi, Ali Reza; Hajalioghli, Parisa; Raeisi, Noorallah

    2015-01-01

    The main objective of this study was to investigate the possibility of replacing electrophoresis cross-linker with non-electrophoresis N, N'-methylenebisacrylamide (BIS) in N-isopropyl acrylamide (NIPAM) polymer gel and its possible effect on dose response. NIPAM polymer gel was prepared from non-electrophoresis grade BIS and the relaxation rate (R2) was measured by MR imaging after exposing the gel to gamma radiation from Co-60 source. To compare the response of this gel with the one that contains electrophoresis grade BIS, two sets of NIPAM gel were prepared using electrophoresis and non-electrophoresis BIS and irradiated to different gamma doses. It was found that the dose-response of NIPAM gel made from the non-electrophoresis grade BIS is coincident with that of electrophoresis grade BIS. Taken all, it can be concluded that the non-electrophoresis grade BIS not only is a suitable alternative for the electrophoresis grade BIS but also reduces the cost of gel due to its lower price.

  5. Personality correlates (BAS-BIS), self-perception of social ranking, and cortical (alpha frequency band) modulation in peer-group comparison.

    Science.gov (United States)

    Balconi, Michela; Pagani, Silvia

    2014-06-22

    The perception and interpretation of social hierarchies are a key part of our social life. In the present research we considered the activation of cortical areas, mainly the prefrontal cortex, related to social ranking perception in conjunction with some personality components (BAS - Behavioral Activation System - and BIS - Behavioral Inhibition System). In two experiments we manipulated the perceived superior/inferior status during a competitive cognitive task. Indeed, we created an explicit and strongly reinforced social hierarchy based on incidental rating in an attentional task. Specifically, a peer group comparison was undertaken and improved (Experiment 1) or decreased (Experiment 2) performance was artificially manipulated by the experimenter. For each experiment two groups were compared, based on a BAS and BIS dichotomy. Alpha band modulation in prefrontal cortex, behavioral measures (performance: error rate, ER; response times, RTs), and self-perceived ranking were considered. Repeated measures ANOVAs and regression analyses showed in Experiment 1 a significant improved cognitive performance (decreased ER and RTs) and higher self-perceived ranking in high-BAS participants. Moreover, their prefrontal activity was increased within the left side (alpha band decreasing). Conversely, in Experiment 2 a significant decreased cognitive performance (increased ER and RTs) and lower self-perceived ranking was observed in higher-BIS participants. Their prefrontal right activity was increased in comparison with higher BAS. The regression analyses confirmed the significant predictive role of alpha band modulation with respect of subjects' performance and self-perception of social ranking, differently for BAS/BIS components. The present results suggest that social status perception is directly modulated by cortical activity and personality correlates. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. Validity and Reliability of the Abbreviated Barratt Impulsiveness Scale in Spanish (BIS-15S)*

    Science.gov (United States)

    Orozco-Cabal, Luis; Rodríguez, Maritza; Herin, David V.; Gempeler, Juanita; Uribe, Miguel

    2010-01-01

    Objective This study determined the validity and reliability of a new, abbreviated version of the Spanish Barratt Impulsiveness Scale (BIS-15S) in Colombian subjects. Method The BIS-15S was tested in non-clinical (n=283) and clinical (n=164) native Spanish-speakers. Intra-scale reliability was calculated using Cronbach’s α, and test-retest reliability was measured with Pearson correlations. Psychometric properties were determined using standard statistics. A factor analysis was performed to determine BIS-15S factor structure. Results 447 subjects participated in the study. Clinical subjects were older and more educated compared to non-clinical subjects. Impulsivity scores were normally distributed in each group. BIS-15S total, motor, non-planning and attention scores were significantly lower in non-clinical vs. clinical subjects. Subjects with substance-related disorders had the highest BIS-15S total scores, followed by subjects with bipolar disorders and bulimia nervosa/binge eating. Internal consistency was 0.793 and test-retest reliability was 0.80. Factor analysis confirmed a three-factor structure (attention, motor, non-planning) accounting for 47.87% of the total variance in BIS-15S total scores. Conclusions The BIS-15S is a valid and reliable self-report measure of impulsivity in this population. Further research is needed to determine additional components of impulsivity not investigated by this measure. PMID:21152412

  7. Relation between constructs of BisBas questionnaire and some personality constructs

    Directory of Open Access Journals (Sweden)

    Nataša Sedlar

    2008-04-01

    Full Text Available The goal of this study was to examine relation between constructs relevant for Gray's neuropsychological model of motivation. According to Gray's theory, two general motivational systems underlie behavior and affect: a behavioral inhibition system (BIS and a behavioral activation system (BAS. BIS is sensitive to aversive stimuli, causes avoidance behaviors and is responsible for individual differences in anxiety. BAS is responsive to appetitive stimuli, triggers approach behavior and has been associated with individual differences in impulsivness. BIS activity has been related to the experience of negative emotions, whereas BAS activity has been associated with the experience of positive emotions. A total of 122 Slovenian students, aged 17–19 years, completed the BIS/BAS scale, the Impulsiveness-Venturesome-Empathy Scale IVE, State Trait Anxiety Inventory STAI-X2, The Positive and Negative Affect Schedule PANAS, and The Big Five Questionairre BFQ. Our results are consistent with those from recent empirical studies and provide support for Gray's theory. Measures of BIS were found to be positively related to trait anxiety and neuroticism, whereas measures of BAS were found to be positively related to impulsiveness and extraversion. Emotional component measured with PANAS did not distinguish BIS from BAS constructs. Both were found to be related to negative affect. With respect to construct validity these findings suggest that BIS/BAS scale is reasonably effective.

  8. Association of Repeatedly Measured High-Sensitivity-Assayed Troponin I with Cardiovascular Disease Events in a General Population from the MORGAM/BiomarCaRE Study

    DEFF Research Database (Denmark)

    Hughes, Maria F; Ojeda, Francisco; Saarela, Olli;

    2017-01-01

    BACKGROUND: High-sensitivity troponin I (hs-cTnI) concentrations reflect myocardial stress. The role of hs-cTnI in predicting long-term changes in the risk of cardiovascular disease (CVD) in general populations is not clearly defined. METHODS: We investigated whether the change in 3 repeated meas...

  9. Repeated electromagnetic induction measurements for mapping soil moisture at the field scale: comparison with data from a wireless soil moisture monitoring network

    Science.gov (United States)

    Martini, Edoardo; Werban, Ulrike; Zacharias, Steffen; Pohle, Marco; Dietrich, Peter; Wollschläger, Ute

    2016-04-01

    Electromagnetic induction (EMI) methods are widely used for soil mapping, as they allow fast and relatively low-cost surveys of soil apparent electrical conductivity (ECa) at various scales. Soil ECa is well known to be influenced by both the volumetric content and the electrical conductivity (EC) of soil water, as well as by soil temperature and by the volume of the solid particles and their EC. Among other applications, EMI has become widely used to determine soil water content or to study hydrological processes within the field of hydrogeophysics. Although the use of non-invasive EMI for imaging soil spatial properties is very attractive, the dependence of ECa on several properties and states challenges any interpretation with respect to individual soil properties or states such as θ. The major aim of this study was to further investigate the potential of repeated EMI measurements to map soil moisture at the hillslope scale, with particular focus on the temporal variability of the spatial patterns of ECa and soil moisture, respectively, and on the stability of the ECa-soil moisture relationship over time. To this end, we compared time series of EMI measurements with high-resolution soil moisture data for a non-intensively managed hillslope area in the Schäfertal catchment (Central Germany) for which the spatial distribution of soil properties and soil water dynamics were known in detail. Soil water and temperature dynamics were observed in 40 soil profiles at hourly resolution during 14 months using a wireless monitoring network. During this period of time, ECa was mapped on seven occasions using an EM38-DD device. For the investigated site, ECa showed small temporal variations (ranging between 0 and 24 mS/m) whereas the temporal range of soil moisture was very large (from very dry to soil saturation). Furthermore, temporal changes of the spatial pattern of ECa differed from temporal changes of the spatial pattern of soil moisture. The ECa-soil moisture

  10. Suppression of Aluminum Corrosion in Lithium Bis(trifluoromethanesulfonyl)imide-based Electrolytes by the Addition of Fumed Silica

    Energy Technology Data Exchange (ETDEWEB)

    Louis, Hamenu; Ko, Jangmyoun [Hanbat National Univ., Daejeon (Korea, Republic of); Lee, Younggi; Kim, Kwangman [Electronics and Telecommunications Research Institute, Daejeon (Korea, Republic of); Cho, Wonil [Korea Institute of Science and Technology, Seoul (Korea, Republic of)

    2013-06-15

    The corrosion property of aluminum by lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) salt is investigated in liquid and gel electrolytes consisting of ethylene carbonate/propylene carbonate/ethylmethyl carbonate/diethyl carbonate (20:5:55:20, vol %) with vinylene carbonate (2 wt %) and fluoroethylene carbonate (5 wt %) using conductivity measurement, cyclic voltammetry, scanning electron microscopy, and energy dispersive X-ray spectroscopy. All corrosion behaviors are attenuated remarkably by using three gel electrolytes containing 3 wt % of hydrophilic and hydrophobic fumed silica. The addition of silica particles contributes to the increase in the ionic conductivity of the electrolyte, indicating temporarily formed physical crosslinking among the silica particles to produce a gel state. Cyclic voltammetry also gives lower anodic current responses at higher potentials for repeating cycles, confirming further corrosion attenuation or electrochemical stability. In addition, the degree of corrosion attenuation can be affected mainly by the electrolytic constituents, not by the hydrophilicity or hydrophobicity of silica particles.

  11. Implementation of the BayBIS process information system in a power station at minimal cost; Die kostenminimale Realisierung des Prozessinformationssystems BayBIS fuer einen Kraftwerksbetreiber

    Energy Technology Data Exchange (ETDEWEB)

    Woyke, W.

    2000-07-01

    BKW are currently introducing the process information system BayBIS (Bayernwerk Betriebsinformationssystem) in three of their power stations. It was developed for a BKW medium-capacity power station where it was installed one year ago. The measuring and data acquisition systems of the power stations can be utilized for BayBIS. It is based on well-establilshed methods and makes use of the available IT systems. It is applied for process monitoring, process analysis, billing, controlling and reporting. [German] Die BKW fuehrt derzeit fuer drei Kraftwerke das Prozessinformationssystem BayBIS (Bayernwerk Betriebsinformationssystem) ein. Es wurde fuer ein Mittellastkraftwerk der BKW entwickelt und ist dort bereits seit einem Jahr im Einsatz. Messtechnik und prozessnahe Datenerfassung der Leittechnik in den Kraftwerken koennen fuer BayBIS genutzt werden. Es baut auf Methoden auf, die sich in der Praxis bewaehrt haben, und nutzt die vorhandene IT-Ausstattung des Unternehmens. Anwendung findet es fuer Prozessbeobachtung, Prozessanalyse, Abrechnung, Controlling und Berichtswesen. (orig.)

  12. Influence of charge carrier mobility and morphology on solar cell parameters in devices of mono- and bis-fullerene adducts

    Science.gov (United States)

    Muth, Mathis-Andreas; Mitchell, William; Tierney, Steven; Lada, Thomas A.; Xue, Xiang; Richter, Henning; Carrasco-Orozco, Miguel; Thelakkat, Mukundan

    2013-12-01

    Herein, we analyze charge carrier mobility and morphology of the active blend layer in thin film organic solar cells and correlate them with device parameters. A low band gap donor-acceptor copolymer in combination with phenyl-C61-butyric acid methyl ester (PCBM) or two bis-adduct fullerenes, bis-PCBM and bis-o-quino-dimethane C60 (bis-oQDMC), is investigated. We study the charge transport of polymer:fullerene blends in hole- and electron-only devices using the space-charge limited current method. Lower electron mobilities are observed in both bis-adduct fullerene blends. Hole mobility, however, is decreased only in the blend containing bis-oQDMC. Both bis-adduct fullerene blends show very high open circuit voltage in solar cell devices, but poor photocurrent compared to the standard PCBM blend for an active layer thickness of 200 nm. Therefore, a higher short circuit current is feasible for the polymer:bis-PCBM blend by reducing the active layer thickness in order to compensate for the low electron mobility, which results in a PCE of 4.3%. For the polymer:bis-oQDMC blend, no such improvement is achieved due to an unfavorable morphology in this particular blend system. The results are supported by external quantum efficiency measurements, atomic force microscopy, transmission electron microscopy and UV/vis spectroscopy. Based on these results, the investigations presented herein give a more scientific basis for the optimization of solar cells.

  13. Quantum repeated games revisited

    CERN Document Server

    Frackiewicz, Piotr

    2011-01-01

    We present a scheme for playing quantum repeated 2x2 games based on the Marinatto and Weber's approach to quantum games. As a potential application, we study twice repeated Prisoner's Dilemma game. We show that results not available in classical game can be obtained when the game is played in the quantum way. Before we present our idea, we comment on the previous scheme of playing quantum repeated games.

  14. Trisodium scandium bis(orthoborate

    Directory of Open Access Journals (Sweden)

    Kunpeng Wang

    2012-05-01

    Full Text Available Single crystals of trisodium scandium bis(orthoborate, Na3Sc(BO32, have been obtained by spontaneous crystallization from an Na2O–Sc2O3–B2O3 melt. The crystal structure features a three-dimensional framework composed of planar [BO3]3− groups and distorted ScO6 octahedra with Na atoms in the cavities. The Sc atom occupies a special position (Wyckoff position 2b, site symmetry -1 and of the two Na atoms, one occupies a special position (Wyckoff position 2c, site symmetry -1.

  15. Discrepancies in reporting the CAG repeat lengths for Huntington's disease

    DEFF Research Database (Denmark)

    Quarrell, Oliver W; Handley, Olivia; O'Donovan, Kirsty

    2011-01-01

    Huntington's disease results from a CAG repeat expansion within the Huntingtin gene; this is measured routinely in diagnostic laboratories. The European Huntington's Disease Network REGISTRY project centrally measures CAG repeat lengths on fresh samples; these were compared with the original...

  16. Novel bis-arylalkylamines as myeloperoxidase inhibitors

    DEFF Research Database (Denmark)

    Aldib, Iyas; Gelbcke, Michel; Soubhye, Jalal;

    2016-01-01

    Human myeloperoxidase (MPO) plays an important role in innate immunity but also aggravates tissue damage by oxidation of biomolecules at sites of inflammation. As a result from a recent high-throughput virtual screening approach for MPO inhibitors, bis-2,2'-[(dihydro-1,3(2H,4H) pyrimidinediyl)bis...

  17. Bis(1,3-dithiole) Compounds

    DEFF Research Database (Denmark)

    Andersen, Jan Rud; Engler, E. M.; Green, D. C.;

    1977-01-01

    There is described the preparation of bis-1,3-dithiole compounds (I) which are key synthetic precursors for the preparation of new polymeric metal bis(dithiolene) (i.e., II) and tetrathiafulvalene compounds (i.e., III): (Image Omitted)...

  18. Mature clustered, regularly interspaced, short palindromic repeats RNA (crRNA) length is measured by a ruler mechanism anchored at the precursor processing site.

    Science.gov (United States)

    Hatoum-Aslan, Asma; Maniv, Inbal; Marraffini, Luciano A

    2011-12-27

    Precise RNA processing is fundamental to all small RNA-mediated interference pathways. In prokaryotes, clustered, regularly interspaced, short palindromic repeats (CRISPR) loci encode small CRISPR RNAs (crRNAs) that protect against invasive genetic elements by antisense targeting. CRISPR loci are transcribed as a long precursor that is cleaved within repeat sequences by CRISPR-associated (Cas) proteins. In many organisms, this primary processing generates crRNA intermediates that are subject to additional nucleolytic trimming to render mature crRNAs of specific lengths. The molecular mechanisms underlying this maturation event remain poorly understood. Here, we defined the genetic requirements for crRNA primary processing and maturation in Staphylococcus epidermidis. We show that changes in the position of the primary processing site result in extended or diminished maturation to generate mature crRNAs of constant length. These results indicate that crRNA maturation occurs by a ruler mechanism anchored at the primary processing site. We also show that maturation is mediated by specific cas genes distinct from those genes involved in primary processing, showing that this event is directed by CRISPR/Cas loci.

  19. μ-Carbonato-bis-(bis-{2-[(diethyl-amino)-meth-yl]phen-yl}bis-muth(III)).

    Science.gov (United States)

    Soran, Albert P; Nema, Mihai G; Breunig, Hans J; Silvestru, Cristian

    2011-01-12

    The mol-ecular structure of the title compound, [Bi(2)(C(11)H(16)N)(4)(CO(3))], consists of a symmetrically bridging carbonato group which binds two [2-Et(2)NCH(2)C(6)H(4)](2)Bi units that are crystallographically related via a twofold rotation axis bis-ecting the carbonate group. The two Bi atoms and two of the C atoms directly bonded to bis-muth are quasi-planar [deviations of 0.323 (1) and 0.330 (9)Å for the Bi and C atoms, respectively] with the carbonate group. The remaining two ligands are in a trans arrangement relative to the quasi-planar (CBi)(2)CO(3) system. The metal atom is strongly coordinated by the N atom of one pendant arm [Bi-N = 2.739 (6) Å], almost trans to the O atom, while the N atom of the other pendant arm exhibits a weaker intra-molecular inter-action [Bi⋯N = 3.659 (7) Å] almost trans to a C atom. If both these intra-molecular N→Bi inter-actions per metal atom are considered, the overall coordination geometry at bis-muth becomes distorted square-pyramidal [(C,N)(2)BiO cores] and the compound can be described as a hypervalent 12-Bi-5 species. Additional quite short intra-molecular Bi⋯O inter-actions are also present [3.796 (8)-4.020 (9) Å]. Inter-molecular associations through weak η(6)⋯Bi inter-actions [Bi⋯centroid of benzene ring = 3.659 (1) Å] lead to a ribbon-like supra-molecular association.

  20. Regioselective synthesis of chiral dimethyl-bis(ethylenedithiotetrathiafulvalene sulfones

    Directory of Open Access Journals (Sweden)

    Flavia Pop

    2015-07-01

    Full Text Available Enantiopure (R,R and (S,S-dimethyl-bis(ethylenedithiotetrathiafulvalene monosulfones have been synthesized by the aerial oxidation of the chiral dithiolates generated from the propionitrile-protected precursors. Both enantiomers crystallize in the orthorhombic chiral space group P212121. They show a boat-type conformation of the TTF moiety, a rather rigid dithiin sulfone ring and the methyl groups in a bisequatorial conformation. Cyclic voltammetry measurements indicate fully reversible oxidation in radical cation and dication species.

  1. UK 2009-2010 repeat station report

    Directory of Open Access Journals (Sweden)

    Thomas J.G. Shanahan

    2013-03-01

    Full Text Available The British Geological Survey is responsible for conducting the UK geomagnetic repeat station programme. Measurements made at the UK repeat station sites are used in conjunction with the three UK magnetic observatories: Hartland, Eskdalemuir and Lerwick, to produce a regional model of the local field each year. The UK network of repeat stations comprises 41 stations which are occupied at approximately 3-4 year intervals. Practices for conducting repeat station measurements continue to evolve as advances are made in survey instrumentation and as the usage of the data continues to change. Here, a summary of the 2009 and 2010 UK repeat station surveys is presented, highlighting the measurement process and techniques, density of network, reduction process and recent results.

  2. (Acetonitrile[bis(2-pyridylmethylamine]bis(perchloratocopper(II

    Directory of Open Access Journals (Sweden)

    Ray J. Butcher

    2008-01-01

    Full Text Available In the title compound, [Cu(ClO42(C12H13N3(C2H3N], the CuII atom is six-coordinate in a Jahn–Teller distorted octahedral geometry, with coordination by the tridentate chelating ligand, an acetonitrile molecule, and two axial perchlorate anions. The tridentate ligand bis(2-pyridylmethylamine chelates meridionally and equatorially while an acetonitrile molecule is coordinated at the fourth equatorial site. The two perchlorate anions are disordered with site occupancy factors of 0.72/0.28. The amine H is involved in intramolecular hydrogen bonding to the perchlorate O atoms and there are extensive but weak intermolecular C—H...O interactions.

  3. Hysteresis of magnetostructural transitions: Repeatable and non-repeatable processes

    Energy Technology Data Exchange (ETDEWEB)

    Provenzano, Virgil [National Institute of Standards and Technology, Gaithersburg, MD 20899 (United States); Della Torre, Edward; Bennett, Lawrence H. [Department of Electrical and Computer Engineering, The George Washington University, Washington, DC 20052 (United States); ElBidweihy, Hatem, E-mail: Hatem@gwmail.gwu.edu [Department of Electrical and Computer Engineering, The George Washington University, Washington, DC 20052 (United States)

    2014-02-15

    The Gd{sub 5}Ge{sub 2}Si{sub 2} alloy and the off-stoichiometric Ni{sub 50}Mn{sub 35}In{sub 15} Heusler alloy belong to a special class of metallic materials that exhibit first-order magnetostructural transitions near room temperature. The magnetic properties of this class of materials have been extensively studied due to their interesting magnetic behavior and their potential for a number of technological applications such as refrigerants for near-room-temperature magnetic refrigeration. The thermally driven first-order transitions in these materials can be field-induced in the reverse order by applying a strong enough field. The field-induced transitions are typically accompanied by the presence of large magnetic hysteresis, the characteristics of which are a complicated function of temperature, field, and magneto-thermal history. In this study we show that the virgin curve, the major loop, and sequentially measured MH loops are the results of both repeatable and non-repeatable processes, in which the starting magnetostructural state, prior to the cycling of field, plays a major role. Using the Gd{sub 5}Ge{sub 2}Si{sub 2} and Ni{sub 50}Mn{sub 35}In{sub 15} alloys, as model materials, we show that a starting single phase state results in fully repeatable processes and large magnetic hysteresis, whereas a mixed phase starting state results in non-repeatable processes and smaller hysteresis.

  4. Reconfigurable multiport EPON repeater

    Science.gov (United States)

    Oishi, Masayuki; Inohara, Ryo; Agata, Akira; Horiuchi, Yukio

    2009-11-01

    An extended reach EPON repeater is one of the solutions to effectively expand FTTH service areas. In this paper, we propose a reconfigurable multi-port EPON repeater for effective accommodation of multiple ODNs with a single OLT line card. The proposed repeater, which has multi-ports in both OLT and ODN sides, consists of TRs, BTRs with the CDR function and a reconfigurable electrical matrix switch, can accommodate multiple ODNs to a single OLT line card by controlling the connection of the matrix switch. Although conventional EPON repeaters require full OLT line cards to accommodate subscribers from the initial installation stage, the proposed repeater can dramatically reduce the number of required line cards especially when the number of subscribers is less than a half of the maximum registerable users per OLT. Numerical calculation results show that the extended reach EPON system with the proposed EPON repeater can save 17.5% of the initial installation cost compared with a conventional repeater, and can be less expensive than conventional systems up to the maximum subscribers especially when the percentage of ODNs in lightly-populated areas is higher.

  5. Revisiting the TALE repeat.

    Science.gov (United States)

    Deng, Dong; Yan, Chuangye; Wu, Jianping; Pan, Xiaojing; Yan, Nieng

    2014-04-01

    Transcription activator-like (TAL) effectors specifically bind to double stranded (ds) DNA through a central domain of tandem repeats. Each TAL effector (TALE) repeat comprises 33-35 amino acids and recognizes one specific DNA base through a highly variable residue at a fixed position in the repeat. Structural studies have revealed the molecular basis of DNA recognition by TALE repeats. Examination of the overall structure reveals that the basic building block of TALE protein, namely a helical hairpin, is one-helix shifted from the previously defined TALE motif. Here we wish to suggest a structure-based re-demarcation of the TALE repeat which starts with the residues that bind to the DNA backbone phosphate and concludes with the base-recognition hyper-variable residue. This new numbering system is consistent with the α-solenoid superfamily to which TALE belongs, and reflects the structural integrity of TAL effectors. In addition, it confers integral number of TALE repeats that matches the number of bound DNA bases. We then present fifteen crystal structures of engineered dHax3 variants in complex with target DNA molecules, which elucidate the structural basis for the recognition of bases adenine (A) and guanine (G) by reported or uncharacterized TALE codes. Finally, we analyzed the sequence-structure correlation of the amino acid residues within a TALE repeat. The structural analyses reported here may advance the mechanistic understanding of TALE proteins and facilitate the design of TALEN with improved affinity and specificity.

  6. A Repeating Fast Radio Burst

    CERN Document Server

    Spitler, L G; Hessels, J W T; Bogdanov, S; Brazier, A; Camilo, F; Chatterjee, S; Cordes, J M; Crawford, F; Deneva, J; Ferdman, R D; Freire, P C C; Kaspi, V M; Lazarus, P; Lynch, R; Madsen, E C; McLaughlin, M A; Patel, C; Ransom, S M; Seymour, A; Stairs, I H; Stappers, B W; van Leeuwen, J; Zhu, W W

    2016-01-01

    Fast Radio Bursts are millisecond-duration astronomical radio pulses of unknown physical origin that appear to come from extragalactic distances. Previous follow-up observations have failed to find additional bursts at the same dispersion measures (i.e. integrated column density of free electrons between source and telescope) and sky position as the original detections. The apparent non-repeating nature of the fast radio bursts has led several authors to hypothesise that they originate in cataclysmic astrophysical events. Here we report the detection of ten additional bursts from the direction of FRB121102, using the 305-m Arecibo telescope. These new bursts have dispersion measures and sky positions consistent with the original burst. This unambiguously identifies FRB121102 as repeating and demonstrates that its source survives the energetic events that cause the bursts. Additionally, the bursts from FRB121102 show a wide range of spectral shapes that appear to be predominantly intrinsic to the source and wh...

  7. Recursive quantum repeater networks

    CERN Document Server

    Van Meter, Rodney; Horsman, Clare

    2011-01-01

    Internet-scale quantum repeater networks will be heterogeneous in physical technology, repeater functionality, and management. The classical control necessary to use the network will therefore face similar issues as Internet data transmission. Many scalability and management problems that arose during the development of the Internet might have been solved in a more uniform fashion, improving flexibility and reducing redundant engineering effort. Quantum repeater network development is currently at the stage where we risk similar duplication when separate systems are combined. We propose a unifying framework that can be used with all existing repeater designs. We introduce the notion of a Quantum Recursive Network Architecture, developed from the emerging classical concept of 'recursive networks', extending recursive mechanisms from a focus on data forwarding to a more general distributed computing request framework. Recursion abstracts independent transit networks as single relay nodes, unifies software layer...

  8. Repeatability of Harris Corner Detector

    Institute of Scientific and Technical Information of China (English)

    HU Lili

    2003-01-01

    Interest point detectors are commonly employed to reduce the amount of data to be processed. The ideal interest point detector would robustly select those features which are most appropriate or salient for the application and data at hand. This paper shows that interest points are geometrically stable under different transformations.This property makes interest points very successful in the context of image matching. To measure this property quantatively, we introduce a evaluation criterion: repeatability rate.

  9. Interaction of DNA with Bis(diiminosuccinonitrilo)platinum(Ⅱ)

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhi-Gang; SUN Yuan-Yuan; JIANG Xiao-Ming

    2008-01-01

    Interaction of DNA with bis(diiminosuccinonitrilo)platinum(Ⅱ) has been studied by UV-visible absorbance spectra, fluorescence spectra and viscosity measurements. The UV-visible absorption spectra of the metal complex exhibit hypochromism with a small blue shift on interaction with DNA. Scatchard plot analyses indicate that the binding sites of the metal complex on DNA are different from those of ethidium bromide. Viscosity experiments reveal that the binding of the metal complex decreases the relative viscosity of DNA. These results suggest that the platinum diimine complex interact with DNA by surface binding. These studies are helpful for us to understand the action mechanism of bis(diiminosuccinonitrilo)platinum(Ⅱ) as a potential photodynamic therapeutic agent, and further to develop it.

  10. Relationships between anthropometric measures and athletic performance, with special reference to repeated-sprint ability, in the Qatar national soccer team.

    Science.gov (United States)

    Brocherie, Franck; Girard, Olivier; Forchino, Fabricio; Al Haddad, Hani; Dos Santos, Gilvan A; Millet, Grégoire P

    2014-01-01

    The aim of this study was to determine potential relationships between anthropometric parameters and athletic performance with special consideration to repeated-sprint ability (RSA). Sixteen players of the senior male Qatar national soccer team performed a series of anthropometric and physical tests including countermovement jumps without (CMJ) and with free arms (CMJwA), straight-line 20 m sprint, RSA (6 × 35 m with 10 s recovery) and incremental field test. Significant (P sprinting times and r = 0.54 for maximal sprinting speed) with the exception of the sprint decrement score (Sdec). The sum of six skinfolds and adipose mass index were largely correlated with Sdec (r = 0.68, P 0.05, respectively) or any standard athletic tests. Multiple regression analyses indicated that muscular cross-sectional area for mid-thigh, adipose index, straight-line 20 m time, maximal sprinting speed and CMJwA are the strongest predictors of Sdec (r(2) = 0.89) and TT (r(2) = 0.95) during our RSA test. In the Qatar national soccer team, players' power-related qualities and RSA are associated with a high muscular profile and a low adiposity. This supports the relevance of explosive power for the soccer players and the larger importance of neuromuscular qualities determining the RSA.

  11. Investigation of Ternary Mixtures Containing 1-Ethyl-3-methylimidazolium Bis(trifluoromethanesulfonylazanide, Ethylene Carbonate and Lithium Bis(trifluoromethanesulfonylazanide

    Directory of Open Access Journals (Sweden)

    Andreas Hofmann

    2016-05-01

    Full Text Available Temperature-dependent viscosity, conductivity and density data of ternary mixtures containing 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonylazanide (EMIM-TFSA, ethylene carbonate (EC, and lithium bis(trifluoromethanesulfonylazanide (Li-TFSA were determined at atmospheric pressure in the temperature range of 20 to 80 °C. Differential scanning calorimetry (DSC measurements were performed to characterize phase conditions of the mixtures in a temperature range of −120 to +100 °C. The viscosity data were fitted according to the Vogel-Fulcher-Tammann-Hesse (VFTH equation and analyzed with the help of the fractional Walden rule. In this study, fundamental physicochemical data about the mixtures are provided and discussed as a basis for structure-property relationship calculations and for potential use of those mixtures as electrolytes for various applications.

  12. X-ray diffraction and vibrational spectroscopic study of trans-bis(acetylacetonato)-bis(4-methylpyridine)cobalt(III)

    Science.gov (United States)

    Tayyari, Sayyed Faramarz; Habibi, Mohammad Hossien; Shojaee, Elahe; Jamialahmadi, Mina; Sammelson, Robert Erik; Wada, Koki; Suzuki, Takayoshi

    2015-03-01

    Trans-bis(acetylacetonato)-bis(4-methylpyridine)cobalt(III)hexafluorophosphate, [AMPC]PF6, was synthesized and characterized by X-ray diffraction and vibrational spectroscopy. The title compound C22H28N2O4Co crystallizes with Z = 2 in space group P-1 (#2). The molecular structure and vibrational spectra of this compound were investigated by means of density functional theory (DFT) calculations and the results were compared with the experimental data. The measured IR bands were interpreted in terms of the calculated vibrational normal modes and compared with the tris(acetylacetonate)Co(III) (Co(acac)3) and 4-methylpyridine (4-Mepy) vibrational spectra. The scaled theoretical wavenumbers and the structural parameters were in excellent agreement with the experimental data.

  13. Fine-resolution repeat topographic surveying of dryland landscapes using UAS-based structure-from-motion photogrammetry: Assessing accuracy and precision against traditional ground-based erosion measurements

    Science.gov (United States)

    Gillian, Jeffrey K.; Karl, Jason W.; Elaksher, Ahmed; Duniway, Michael C.

    2017-01-01

    Structure-from-motion (SfM) photogrammetry from unmanned aerial system (UAS) imagery is an emerging tool for repeat topographic surveying of dryland erosion. These methods are particularly appealing due to the ability to cover large landscapes compared to field methods and at reduced costs and finer spatial resolution compared to airborne laser scanning. Accuracy and precision of high-resolution digital terrain models (DTMs) derived from UAS imagery have been explored in many studies, typically by comparing image coordinates to surveyed check points or LiDAR datasets. In addition to traditional check points, this study compared 5 cm resolution DTMs derived from fixed-wing UAS imagery with a traditional ground-based method of measuring soil surface change called erosion bridges. We assessed accuracy by comparing the elevation values between DTMs and erosion bridges along thirty topographic transects each 6.1 m long. Comparisons occurred at two points in time (June 2014, February 2015) which enabled us to assess vertical accuracy with 3314 data points and vertical precision (i.e., repeatability) with 1657 data points. We found strong vertical agreement (accuracy) between the methods (RMSE 2.9 and 3.2 cm in June 2014 and February 2015, respectively) and high vertical precision for the DTMs (RMSE 2.8 cm). Our results from comparing SfM-generated DTMs to check points, and strong agreement with erosion bridge measurements suggests repeat UAS imagery and SfM processing could replace erosion bridges for a more synoptic landscape assessment of shifting soil surfaces for some studies. However, while collecting the UAS imagery and generating the SfM DTMs for this study was faster than collecting erosion bridge measurements, technical challenges related to the need for ground control networks and image processing requirements must be addressed before this technique could be applied effectively to large landscapes.

  14. Reliability of Calf Bioelectrical Impedance Spectroscopy and Magnetic-Resonance-Imaging-Acquired Skeletal Muscle Hydration Measures in Healthy People

    Directory of Open Access Journals (Sweden)

    Anuradha Sawant

    2013-01-01

    Full Text Available Purpose. The purpose of this study was to investigate the test-retest reliability, relative variability, and agreement between calf bioelectrical impedance-spectroscopy (cBIS acquired extracellular fluid (ECF, intracellular fluid (ICF, total water and the ratio of ECF : ICF, magnetic-resonance-imaging (MRI acquired transverse relaxation times (T2, and apparent diffusion coefficient (ADC of calf muscles of the same segment in healthy individuals. Methods. Muscle hydration measures were collected in 32 healthy individuals on two occasions and analyzed by a single rater. On both occasions, MRI measures were collected from tibialis anterior (TA, medial (MG, and lateral gastrocnemius (LG and soleus muscles following the cBIS data acquired using XiTRON Hydra 4200 BIS device. The intraclass correlation coefficients (ICC2,1, coefficient of variation (CV, and agreement between MRI and cBIS data were also calculated. Results. ICC2,1 values for cBIS, T2, and ADC ranged from 0.56 to 0.92, 0.96 to 0.99, and 0.05 to 0.56, respectively. Relative variability between measures (CV ranged from 14.6 to 25.6% for the cBIS data and 4.2 to 10.0% for the MRI-acquired data. The ratio of ECF : ICF could significantly predict T2 of TA and soleus muscles. Conclusion. MRI-acquired measures of T2 had the highest test-retest reliability of muscle hydration with the least error and variation on repeated testing. Hence, T2 of a muscle is the most reliable and stable outcome measure for evaluating individual muscle hydration.

  15. Normative data of the Barratt Impulsiveness Scale 11 (BIS-11 for Brazilian adults

    Directory of Open Access Journals (Sweden)

    Leandro F. Malloy-Diniz

    2015-09-01

    Full Text Available Objective:The Barratt Impulsiveness Scale (BIS-11 is a valid and reliable instrument, and one of the most often used tools to assess impulsivity. This study assesses the performance of a large sample of adults by using a version of BIS-11 adapted to Brazilian Portuguese.Methods:We assessed 3,053 adults from eight Brazilian states. Internal consistencies and performance data were presented for two correction criteria of BIS-11: original and the two-factor score.Results:The associations between age, sex, region, and education and the BIS-11 scores present very small effect sizes. Therefore, we provided a percentile rank parameter for the different BIS-11 subscores considering the whole sample. Given the internal consistency of the two correction systems, we found that only the two-factor system fulfills the psychometric criteria of Cronbach’s alpha (cutoff value of at least 0.6.Conclusion:Our results support the use of the Brazilian adaptation of BIS-11 in different regions of the country as a measure of impulsivity. Since high impulsiveness is a characteristic of several dysfunctional behaviors, the establishment of normative parameters is of utmost relevance and should be extended to other age ranges and populations in future studies.

  16. Detection of the effects of repeated dose combined propoxur and heavy metal exposure by measurement of certain toxicological, haematological and immune function parameters in rats.

    Science.gov (United States)

    Institóris, L; Siroki, O; Undeger, U; Basaran, N; Banerjee, B D; Dési, I

    2001-06-21

    In the present study, an immunotoxicity test system, containing general toxicological (body weight gain, organ weights), haematological (WBC,RBC, Ht, mean cell volume of the RBCs, cell content of the femoral bone marrow), and immune function (PFC assay, DTH reaction) investigations, was used for detection the effects of a 4 weeks repeated low dose combined oral exposure of male Wistar rats with propoxur and the heavy metals arsenic or mercury. Two doses of the compounds were used: a higher one (the lowest dose which resulted in significant change of at least one parameter examined in previous dose-effect experiments), and a lower one (the highest dose which proved to be non-effective). The applied doses were: 8.51 and 0.851 mg kg(-1) of propoxur, 13.3 and 3.33 mg kg(-1) of NaAsO(2), and 3.20 and 0.40 mg kg(-1) of HgCl(2). In the combination treatment, the high dose of propoxur was combined with the low dose of arsenic or mercury, and the high doses of each heavy metals were combined with the low dose of propoxur. The main finding of this study was that some of the combinations significantly altered the relative weight of liver, adrenals and kidneys, related to both the untreated and the high dose internal control. Among the immune functions examined, only the PFC content of the spleen showed a trend of changes in certain combinations versus the corresponding high dose control. According to the present results, combined exposure with propoxur and the heavy metals examined can modify the detection limit of the single compounds and/or may alter their toxic effects.

  17. Dissolved Fe(II) in the Pacific Ocean: Measurements from the P16N CLIVAR/CO2 Repeat Hydrography Cruise

    Science.gov (United States)

    Hansard, S. P.; Landing, W. M.; Measures, C. I.

    2006-12-01

    Vertical profiles of seawater Fe(II) concentration were obtained for 37 stations sampled in early 2006, in conjunction with the CLIVAR Repeat Hydrography P16N transect (152° W, Tahiti to Alaska). At each station, seawater samples were collected from 12 target depths (0-1000 m) using trace-metal clean Go-Flo bottles. Upon recovery, Go-Flo bottles were immediately transferred to a Class 100 clean van and sub-sampled for Fe(II) by passing sample water through a 0.2 μm Supor (polyethersulfone) cartridge filter into 125 mL containers, pre-loaded with 25 μL of 6M quartz-distilled HCl (final pH ~~ 6) to slow oxidation. Samples were immediately analyzed for Fe(II) using a luminol-based chemiluminescence method. Total dissolved iron was also determined shipboard by spectrophotometric flow injection analysis. The data collected from this cruise will be presented, along with corroborating data from another North Pacific cruise (PO2). Concentrations of Fe(II) ranged from below detection (meters. Photoreduction of Fe(III) has been cited as a source of Fe(II) in surface waters, and the pattern of attenuation with depth is consistent with this mechanism. Many samples collected at or near the bottom of the profile (500-1000 m) exhibited elevated Fe(II) relative to the mid-depths of the profile. Due to the higher total dissolved iron at depth, the percentage of Fe(II) was low in these samples. Recent studies support the presence of Fe(II) at depth, in association with low or suboxic conditions. In situ processes such as the remineralization of sinking biogenic particles may provide a source for this Fe(II).

  18. Bis[1,3-bis(2-cyanophenyltriazenido]mercury(II

    Directory of Open Access Journals (Sweden)

    Mohammad Kazem Rofouei

    2009-10-01

    Full Text Available In the title compound, [Hg(C14H8N52], the central atom is four-coordinated by two bidentate 1,3-bis(2-cyanophenyltriazenide ligands in a distorted square-planar geometry. The asymmteric unit is composed of one ligand molecule and one HgII ion, which is disordered over two sites, one lying on an inversion center and the other on a general position with site-occupancy factors of 0.2378 (7 and 0.3811 (7, respectively. The monomeric molecules of the complex are linked into pairs through non-classical C—H...N hydrogen bonds. The resulting dimeric units are assembled by translation along the crystallographic c axis into chains linked through secondary π–π interactions [centroid–centroid distances = 3.685 (2 and 3.574 (2 Å], as well as C—H...π stacking interactions, resulting in a two-dimensional architecture.

  19. Two to five repeated measurements per patient reduced the required sample size considerably in a randomized clinical trial for patients with inflammatory rheumatic diseases

    OpenAIRE

    Smedslund Geir; Zangi Heidi Andersen; Mowinckel Petter; Hagen Kåre Birger

    2013-01-01

    Abstract Background Patient reported outcomes are accepted as important outcome measures in rheumatology. The fluctuating symptoms in patients with rheumatic diseases have serious implications for sample size in clinical trials. We estimated the effects of measuring the outcome 1-5 times on the sample size required in a two-armed trial. Findings In a randomized controlled trial that evaluated the effects of a mindfulness-based group intervention for patients with inflammatory arthritis (n=71)...

  20. The Pentapeptide Repeat Proteins

    Energy Technology Data Exchange (ETDEWEB)

    Vetting,M.; Hegde, S.; Fajardo, J.; Fiser, A.; Roderick, S.; Takiff, H.; Blanchard, J.

    2006-01-01

    The Pentapeptide Repeat Protein (PRP) family has over 500 members in the prokaryotic and eukaryotic kingdoms. These proteins are composed of, or contain domains composed of, tandemly repeated amino acid sequences with a consensus sequence of [S, T,A, V][D, N][L, F]-[S, T,R][G]. The biochemical function of the vast majority of PRP family members is unknown. The three-dimensional structure of the first member of the PRP family was determined for the fluoroquinolone resistance protein (MfpA) from Mycobacterium tuberculosis. The structure revealed that the pentapeptide repeats encode the folding of a novel right-handed quadrilateral {beta}-helix. MfpA binds to DNA gyrase and inhibits its activity. The rod-shaped, dimeric protein exhibits remarkable size, shape and electrostatic similarity to DNA.

  1. Repeating the Past

    Science.gov (United States)

    Moore, John W.

    1998-05-01

    As part of the celebration of the Journal 's 75th year, we are scanning each Journal issue from 25, 50, and 74 years ago. Many of the ideas and practices described are so similar to present-day "innovations" that George Santayana's adage (1) "Those who cannot remember the past are condemned to repeat it" comes to mind. But perhaps "condemned" is too strong - sometimes it may be valuable to repeat something that was done long ago. One example comes from the earliest days of the Division of Chemical Education and of the Journal.

  2. 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.

    Science.gov (United States)

    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.

  3. Impact of volunteer-related and methodology-related factors on the reproducibility of brachial artery flow-mediated vasodilation: analysis of 672 individual repeated measurements.

    NARCIS (Netherlands)

    Mil, A.C.C.M. van; Greyling, A.; Zock, P.L.; Geleijnse, J.M.; Hopman, M.T.E.; Mensink, R.P.; Reesink, K.D.; Green, D.J.; Ghiadoni, L.; Thijssen, D.H.J.

    2016-01-01

    OBJECTIVES: Brachial artery flow-mediated dilation (FMD) is a popular technique to examine endothelial function in humans. Identifying volunteer and methodological factors related to variation in FMD is important to improve measurement accuracy and applicability. METHODS: Volunteer-related and

  4. 数字光纤直放站中的时延测量与校正%The Measurement and Adjustment of Time Delay in Digital Optical Fiber Repeater

    Institute of Scientific and Technical Information of China (English)

    金绍春

    2011-01-01

    提出了应用于数字光纤直放站的时延测量与校正方法。阐述了数字光纤直放站的结构、时延测量的目的与原理、时延校正的计算。时延测量以CPRI协议为基础,包括光纤时延测量、转发时延测量。时延校正分下行时延校正和上行时延校正。下行时延校正是使同一台REC送出的IQ信号在不同的RE中能够同时射频发送出去。上行时延校正是使不同的RE接收到的IQ信号能够正确进行功率合成。%The Method of measurement and adjustment of time delay which applies to digital optical fiber repeater has been presented. The structure of digital optical fiber repeater, the purpose and principle of time delay measurement, the calculation of time delay adjustment, has been represented. The measurement of time delay that based on CPRI protocol includes the measurement of optical fiber time delay and the measurement of forward time delay. The time delay adjustment includes uplink time delay adjustment and downlink time delay adjustment. The purpose of downlink time delay adjustment is to ensure IQ signals in different REs which comes from the same REC transmit synchronously by radio frequency signals. The purpose of uplink time delay adjustment is to ensure received IQ signals by different REs synthesize correctly by power.

  5. Behavioural Inhibition System (BIS) sensitivity differentiates EEG theta responses during goal conflict in a continuous monitoring task.

    Science.gov (United States)

    Moore, Roger A; Mills, Matthew; Marshman, Paul; Corr, Philip J

    2012-08-01

    Previous research has revealed that EEG theta oscillations are affected during goal conflict processing. This is consistent with the behavioural inhibition system (BIS) theory of anxiety (Gray & McNaughton, 2000). However, studies have not attempted to relate these BIS-related theta effects to BIS personality measures. Confirmation of such an association would provide further support for BIS theory, especially as it relates to trait differences. EEG was measured (32 electrodes) from extreme groups (low/high trait BIS) engaged in a target detection task. Goal conflicts were introduced throughout the task. Results show that the two groups did not differ in behavioural performance. The major EEG result was that a stepwise discriminant analysis indicated discrimination by 6 variables derived from coherence and power, with 5 of the 6 in the theta range as predicted by BIS theory and one in the beta range. Also, across the whole sample, EEG theta coherence increased at a variety of regions during primary goal conflict and showed a general increase during response execution; EEG theta power, in contrast, was primarily reactive to response execution. This is the first study to reveal a three-way relationship between the induction of goal conflict, the induction of theta power and coherence, and differentiation by psychometrically-defined low/high BIS status.

  6. Superconductivity in BiS2-based compounds

    Science.gov (United States)

    Yazici, Duygu

    2014-03-01

    Polycrystalline samples of Ln O0.5F0.5BiS2 (Ln = La, Ce, Pr, Nd, Yb) were synthesized by solid-state reaction. These compounds form in a tetragonal structure with space group P 4 / nmm conforming to the CeOBiS2 crystal structure. Electrical resistivity, magnetic susceptibility and specific heat measurements were performed on all of the samples. All of the compounds exhibit superconductivity in the range 1.9 K - 5.4 K, and the YbO0.5F0.5BiS2 sample was also found to exhibit magnetic order (probably antiferromagnetic order) at ~2.7 K that appears to coexist with superconductivity below 5.4 K. Electron-doping appears to induce superconductivity in the BiS2-based superconductors as partial substitution of F for O is necessary to observe superconductivity. This was further demonstrated in a study where trivalent La+3 was partially substituted with tetravalent Th+4, Hf+4, Zr+4, and Ti+4, all of which induced superconductivity. We also observed that substitution of divalent Sr+2 for La+3 (hole doping) does not induce superconductivity. Electrical resistivity measurements were also performed under applied pressure on Ln O0.5F0.5BiS2 (Ln = La, Ce, Pr, Nd) up to ~3 GPa and down to 1 K. These studies revealed a universal behavior where the systems are tuned away from semi-conducting behavior towards metallic behavior. The superconducting states were stabilized by applied pressure, so that Tc increased in all of the rare earth members listed. At a critical pressure Pc, Tc increases rapidly from a low Tc phase to a distinct high Tc phase, after which additional pressure no longer suppressed the semiconducting behavior in the normal state [3,4]. In addition, the metallization of NdO0.5F0.5BiS2 also occurs at Pc. Research was supported by the US AFOSR MURI FA9550-09-1-0603, US DOE DE-FG02-04-ER46105 and NNSA DE-NA0001841.

  7. Briefwechsel uber die Partikel "bis" (An Exchange of Letters about the Particle "bis").

    Science.gov (United States)

    Ludwig, Horst; Holschuh, Albrecht

    1990-01-01

    A discussion, in the form of an animated letter exchange, argues that, contrary to most current grammatical descriptions, the German particle "bis" should not be viewed as a preposition governing the accusative case. Rather, it is demonstrated that "bis" most often occurs as a proclitic adverb. (16 references) (JTC)

  8. Briefwechsel uber die Partikel "bis" (An Exchange of Letters about the Particle "bis").

    Science.gov (United States)

    Ludwig, Horst; Holschuh, Albrecht

    1990-01-01

    A discussion, in the form of an animated letter exchange, argues that, contrary to most current grammatical descriptions, the German particle "bis" should not be viewed as a preposition governing the accusative case. Rather, it is demonstrated that "bis" most often occurs as a proclitic adverb. (16 references) (JTC)

  9. All-optical repeater.

    Science.gov (United States)

    Silberberg, Y

    1986-06-01

    An all-optical device containing saturable gain, saturable loss, and unsaturable loss is shown to transform weak, distorted optical pulses into uniform standard-shape pulses. The proposed device performs thresholding, amplification, and pulse shaping as required from an optical repeater. It is shown that such a device could be realized by existing semiconductor technology.

  10. Bidirectional Manchester repeater

    Science.gov (United States)

    Ferguson, J.

    1980-01-01

    Bidirectional Manchester repeater is inserted at periodic intervals along single bidirectional twisted pair transmission line to detect, amplify, and transmit bidirectional Manchester 11 code signals. Requiring only 18 TTL 7400 series IC's, some line receivers and drivers, and handful of passive components, circuit is simple and relatively inexpensive to build.

  11. Whole scalp resting state EEG of oscillatory brain activity shows no parametric relationship with psychoacoustic and psychosocial assessment of tinnitus: A repeated measures study.

    Science.gov (United States)

    Pierzycki, Robert H; McNamara, Adam J; Hoare, Derek J; Hall, Deborah A

    2016-01-01

    Tinnitus is a perception of sound that can occur in the absence of an external stimulus. A brief review of electroencephalography (EEG) and magnetoencephalography (MEG) literature demonstrates that there is no clear relationship between tinnitus presence and frequency band power in whole scalp or source oscillatory activity. Yet a preconception persists that such a relationship exists and that resting state EEG could be utilised as an outcome measure for clinical trials of tinnitus interventions, e.g. as a neurophysiological marker of therapeutic benefit. To address this issue, we first examined the test-retest correlation of EEG band power measures in tinnitus patients (n = 42). Second we examined the evidence for a parametric relationship between numerous commonly used tinnitus variables (psychoacoustic and psychosocial) and whole scalp EEG power spectra, directly and after applying factor reduction techniques. Test-retest correlation for both EEG band power measures and tinnitus variables were high. Yet we found no relationship between whole scalp EEG band powers and psychoacoustic or psychosocial variables. We conclude from these data that resting state whole scalp EEG should not be used as a biomarker for tinnitus and that greater caution should be exercised in regard to reporting of findings to avoid confirmation bias. The data was collected during a randomised controlled trial registered at ClinicalTrials.gov (Identifier: NCT01541969).

  12. Repetibilidade e número mínimo de medições para caracteres de cacho de bacabi (Oenocarpus mapora Repeatability and minimum number of measurements for characters of bacabi palm (Oenocarpus mapora racemes

    Directory of Open Access Journals (Sweden)

    Maria do Socorro Padilha de Oliveira

    2010-12-01

    potential for commercial and food uses, but has not been well studied. The objectives of this study were to estimate the repeatability coefficients, determine predictability and the number of measurements needed for raceme characters of this palm. 27 individuals of bacabi that belong to the Germplasm Bank of Oenocarpus/Jessenia at Embrapa Eastern Amazon, in Belém, PA, Brazil were evaluated. Three fully matured racemes from each plant were sampled to measure six characters: total weight of raceme (TWR and fruit weight per raceme (FWR, number of rachillae per raceme (NRR, rachis length per raceme (RLR, weight of 100 fruits (WHF and fruit yield per raceme (FER. The repeatability estimates were obtained by three statistical methods: analysis of variance; principal components; and structural analysis. For all characters, the estimates of repeatability coefficients presented values with very similar magnitudes in the three methods. The estimates of repeatability coefficients and determination coefficients were relatively high (r 0.60 and R2 81.7% for the characters FER and NRR, showing genotype regularity for these raceme measurements. For these characters, the minimum number of racemes necessary to estimate the true character value of the genotypes was thirteen (FER and five (NRR, with 95% reliability. The remaining characters showed repeatabilities and determination coefficients with medium to low values, indicating the need for better environmental control to make the measurements.

  13. The child accident repeater: a review.

    Science.gov (United States)

    Jones, J G

    1980-04-01

    The child accident repeater is defined as one who has at least three accidents that come to medical attention within a year. The accident situation has features in common with those of the child who has a single accident through simple "bad luck", but other factors predispose him to repeated injury. In the child who has a susceptible personality, a tendency for accident repetition may be due to a breakdown in adjustment to a stressful environment. Prevention of repeat accidents should involve the usual measures considered appropriate for all children as well as an attempt to provide treatment of significant maladjustment and modification of a stressful environment.

  14. New procedures to measure synthase and phosphatase activities of bis-phosphoglycerate mutase. Interest for development of therapeutic drugs; Nouveaux procedes pour mesurer les activites synthase et phosphatase de la bisphosphoglycerate mutase. Interet pour le developpement de drogues therapeutiques

    Energy Technology Data Exchange (ETDEWEB)

    Ravel, P.; Garel, M.C. [Hopital Henri-Mondor, 94 - Creteil (France); Toullec, D. [Laboratoire Glaxo Wellcome, 91- Les Ulis (France)

    1997-12-31

    In red blood cells, a modulation of the level of the allosteric effector of hemoglobin, 2,3-diphosphoglycerate (2,3-DPG) would have implications in the treatment of ischemia and sickle cell anemia. Its concentrations is determined by the relative activities of the synthase and phosphatase reactions of the multifunctional bis-phosphoglycerate mutase (BPGM). In this report we develop first a more direct synthase assay which uses glyceraldehyde phosphate to suppress the aldolase and triose phosphate isomerase reactions. Secondly we propose a radioactive phosphatase assay coupled to chromatographic separation and identification of the reaction products by paper electrophoresis. Such identification of these products allows us to show that the multifunctional BPGM expresses its mutase instead of its phosphatase activity in conditions of competition between the 3-phosphoglycerate and the 2-phospho-glycolate activator in the phosphatase reaction. These two more precise procedures could be used to study the effects of substrate and cofactor analogues regarding potential therapeutic approaches and could be used for clinical analyses to detect deficiency of BPGM. (author)

  15. Burnout as a risk factor for antidepressant treatment - a repeated measures time-to-event analysis of 2936 Danish human service workers

    DEFF Research Database (Denmark)

    Madsen, Ida E H; Lange, Theis; Borritz, Marianne

    2015-01-01

    Burnout is a state of emotional exhaustion, feelings of reduced personal accomplishment, and withdrawal from work thought to occur as a consequence of prolonged occupational stress. The condition is not included in the diagnostic classifications, but is considered likely to develop into depressive...... disorder in some cases. We examined the prospective association between burnout and antidepressant treatment, as an indicator of clinically significant mental disorder. We further investigated potential effect-modifiers of the association, to identify factors that may prevent this progression of burnout...... modeling, examining the risk of entering antidepressant treatment in relation to the level of work-related burnout measured by the Copenhagen Burnout inventory. As effect-modifiers we examined both sociodemographic factors and a range of psychosocial work environment factors. The level of burnout predicted...

  16. County level socioeconomic position, work organization and depression disorder: a repeated measures cross-classified multilevel analysis of low-income nursing home workers.

    Science.gov (United States)

    Muntaner, Carles; Li, Yong; Xue, Xiaonan; Thompson, Theresa; O'Campo, Patricia; Chung, Haejoo; Eaton, William W

    2006-12-01

    This study simultaneously tests the effect of county, organizational, workplace, and individual level variables on depressive disorders among low-income nursing assistants employed in US nursing homes. A total of 482 observations are used from two waves of survey data collection, with an average two-year interval between initial and follow-up surveys. The overall response rate was 62 percent. The hierarchically structured data was analyzed using multilevel modeling to account for cross-classifications across levels of data. Nursing assistants working in nursing homes covered by a single union in three states were asked about aspects of their working conditions, job stress, physical and mental health status, individual and family health-care needs, household economics and household strain. The 241 nursing assistants who participated in this study were employed in 34 nursing homes and lived in 49 counties of West Virginia, Ohio and Kentucky. The study finds that emotional strain, related to providing direct care to elderly and disabled clients, is associated with depressive disorder, as is nursing home ownership type (for-profit versus not-for-profit). However, when controlling for county level socioeconomic variables (Gini index and proportion of African Americans living in the county), neither workplace nor organizational level variables were found to be statistically significant associated with depressive disorder. This study supports previous findings that emotional demand in health-care environments is an important correlate of mental health. It also adds empirical evidence to support a link between financial strain and depression in US women. While this study does not find that lack of a seniority wage benefits--a factor that can conceivably exacerbate financial strain over time--is associated with depressive disorder among low-income health-care workers, it does find county level measures of poverty to be statistically significant predictors of depressive

  17. Dynamics of Graft Function Measured by DNA-Technology in a Patient with Severe Aplastic Anemia and Repeated Stem Cell Transplantation

    Directory of Open Access Journals (Sweden)

    Anna Karastaneva

    2014-01-01

    Full Text Available Although bone marrow transplantation (BMT from an HLA identical sibling is considered as treatment of choice in pediatric patients with severe aplastic anemia (SAA, a significant number of them experience graft failure (GF after BMT. We report a case of an 8-year-old male patient with SAA who presented with a complicated posttransplant course due to parvovirus B19 infection and GF. A subsequent attempt to support the graft by antithymocyte globulin (ATG and a peripheral stem cell boost resulted in transitory autologous recovery of hematopoiesis followed by mixed chimerism, supported by donor lymphocyte infusions (DLIs and finally graft rejection with relapse of SAA. Permanent complete chimerism was achieved by a second BMT. Dynamics of graft function, measured by a single nucleotide polymorphism (SNPs analysis, are discussed.

  18. Long-term aerobic exercise and omega-3 supplementation modulate osteoporosis through inflammatory mechanisms in post-menopausal women: a randomized, repeated measures study

    Directory of Open Access Journals (Sweden)

    Kanaley Jill

    2011-10-01

    Full Text Available Abstract Background Evidence indicates that dietary fats and physical activity influence bone health. The purpose of this study was to examine the effects of long-term aerobic exercise and omega-3 (N-3 supplementation on serum inflammatory markers, bone mineral density (BMD, and bone biomarkers in post-menopausal women. Methods Seventy-nine healthy sedentary post-menopausal women aged 58-78 years participated in this study. Subjects were randomized to one of 4 groups: exercise + supplement (E+S, n = 21, exercise (E, n = 20, supplement (S, n = 20, and control (Con, n = 18 groups. The subjects in the E+S and E groups performed aerobic exercise training (walking and jogging up to 65% of HRmax, three times a week for 24 weeks. Subjects in the E+S and S groups consumed 1000 mg/d N-3 for 24 weeks. The lumbar spine (L2-L4 and femoral neck BMD, serum tumor necrosis factor (TNF α, interleukin (IL 6, prostaglandin (PG E2, estrogen, osteocalcin, 1, 25-dihydroxyvitamin D3 (1, 25 Vit D, C-telopeptide (CTX, parathyroid hormone (PTH and calcitonin (CT were measured at baseline, the end of week 12 and 24. Results Serum estrogen, osteocalcin, 1, 25 Vit D, CT, L2-L4 and femoral neck BMD measures increased (P 2 decreased (P 2-L4 and femoral neck BMD, estrogen, osteocalcin, and CT were negatively (P 2. PTH and CT were correlated positively and negatively with IL-6, respectively (P Conclusions The present study demonstrates that long-term aerobic exercise training plus N-3 supplementation have a synergistic effect in attenuating inflammation and augmenting BMD in post-menopausal osteoporosis.

  19. Synthesis of doubly ethyl-bridged bis(p-sulfonatocalix[4]arene) and its supramolecular polymerization with viologen dimer.

    Science.gov (United States)

    Wang, Kun-Peng; Guo, Dong-Sheng; Zhao, Hong-Xia; Liu, Yu

    2014-04-01

    A water-soluble supramolecular polymer with a high degree of polymerization and viscosity has been constructed based on the strong host-guest interaction between p-sulfonatocalix[4]arenes (SC4As) and viologen. A homoditopic doubly ethyl-bridged bis(p-sulfonatocalix[4]arene) (d-SC4A) was prepared and its binding behavior towards methyl viologen compared with the singly ethyl-bridged bis(p-sulfonatocalix[4]arene) (s-SC4A) by NMR spectroscopy and isothermal titration calorimetry. By employing a viologen dimer (bisMV(4+)) as the homoditopic guest, two linear AA/BB-type supramolecular polymers, d-SC4A⊃bisMV(4+) and s-SC4A⊃bisMV(4+), were successfully constructed. Compared with s-SC4A⊃bisMV(4+), d-SC4A⊃bisMV(4+) shows much higher solubility and viscosity, and has also been characterized by viscosity, diffusion-ordered NMR spectroscopy, dynamic light scattering, and atomic force microscopy measurements. Furthermore, the polymer is responsive to electrostimulus as viologen is electroactive, which was studied by cyclic voltammetry. This study represents a proof-of-principle as the polymer can potentially be applied as a self-healing and degradable polymeric material.

  20. Effect of Annealing Temperature on Flowerlike Cu3BiS3 Thin Films Grown by Chemical Bath Deposition

    Science.gov (United States)

    Deshmukh, S. G.; Patel, S. J.; Patel, K. K.; Panchal, A. K.; Kheraj, Vipul

    2017-10-01

    For widespread application of thin-film photovoltaic solar cells, synthesis of inexpensive absorber material is essential. In this work, deposition of ternary Cu3BiS3 absorber material, which contains abundant and environmentally benign elements, was carried out on glass substrate. Flowerlike Cu3BiS3 thin films with nanoflakes as building block were formed on glass substrate by chemical bath deposition. These films were annealed at 573 K and 673 K in sulfur ambient for structural improvement. Their structure was characterized using Raman spectroscopy, as well as their surface morphological and optical properties. The x-ray diffraction profile of as-deposited Cu3BiS3 thin film revealed amorphous structure, which transformed to orthorhombic phase after annealing. The Raman spectrum exhibited a characteristic peak at 290 cm-1. Scanning electron microscopy of as-deposited Cu3BiS3 film confirmed formation of nanoflowers with diameter of around 1052 nm. Wettability testing of as-deposited Cu3BiS3 thin film demonstrated hydrophobic nature, which became hydrophilic after annealing. The measured ultraviolet-visible (UV-Vis) absorption spectra of the Cu3BiS3 thin films gave an absorption coefficient of 105 cm-1 and direct optical bandgap of about 1.42 eV after annealing treatment. Based on all these results, such Cu3BiS3 material may have potential applications in the photovoltaic field as an absorber layer.

  1. Synthesis and characterization of the adducts of bis(O-butylxanthato)Ni(II) with nitrogen donor ligands and X-ray structure of bis(O-butylxanthato)bis(3-chloropyridine)nickel(II)

    Science.gov (United States)

    Kour, Inderjeet; Kour, Gurvinder; Sachar, Renu; Anthal, Sumati; Kant, Rajni

    2017-01-01

    A new series of adducts of bis(O-butylxanthato)nickel(II) with substituted pyridines have been synthesized by treating bis(O-butylxanthato)nickel(II) with substituted pyridines in acetone. The complexes have been characterized by elemental analysis, conductivity measurements, magnetic susceptibility measurements, TGA/DTA studies, infrared and electronic spectral studies. X-ray studies of one of the adduct bis(O-butylxanthato)bis(3-chloropyridine)nickel(II) shows that the central metal is octahedrally coordinated within a trans-N2S4 donor set, with the Ni atom located on a centre of inversion. The complex crystallizes in the monoclinic space group P21/c with unit cell parameters a = 11.8088(8) Å, b = 12.2042(7) Å, c = 9.0252(5) Å, β = 93.789(6), Z = 2. Crystal structure was solved by direct methods and refined by full matrix least squares procedures to a final R-value of 0.0380 (wR2 = 0.0885) for 2083 observed reflections. The butyl chain is disordered over two set of sites, with occupancy ratios of 0.741:0.259. These studies suggest a distorted octahedral structure and paramagnetic nature of the adducts.

  2. Perfusion CT measurements in healthy cervical spinal cord: feasibility and repeatability of the study as well as interchangeability of the perfusion estimates using two commercially available software packages

    Energy Technology Data Exchange (ETDEWEB)

    Bisdas, Sotirios [Johann Wolfgang University Hospital, Department of Radiology, Frankfurt (Germany); Medical University of South Carolina, Department of Radiology, Charleston, SC (United States); Johann Wolfgang Goethe University Hospital, Department of Diagnostic and Interventional Radiology, Frankfurt (Germany); Rumboldt, Zoran; Deveikis, John; Spampinato, Maria Vittoria [Medical University of South Carolina, Department of Radiology, Charleston, SC (United States); Surlan, Katarina [Clinical Centre Ljubljana, Department of Clinical Radiology, Ljubljana (Slovenia); Koh, Tong San [Nanyang Technological University, School of Electrical and Electronic Engineering, Singapore (Singapore)

    2008-10-15

    Our purpose was to examine the feasibility and reproducibility of perfusion CT studies in the cervical spinal cord and the interchangeability of the values obtained by two post-processing methods. The perfusion CT studies of 40 patients with neck tumours were post-processed using two software packages (Software-1: deconvolution-based analysis with adiabatic tissue homogeneity approach and Software-2: maximum-slope-model with Patlak analysis). Eight patients were examined twice for assessing the reproducibility of the technique. Two neuroradiologists separately post-processed the images with two arterial input functions (AIFs): (1) the internal carotid artery (ICA) and (2) the vertebral artery (VA). Maps of blood flow (F) in ml/min/100 g, blood volume (V) in ml/100 g, mean transit time (MTT) in seconds (s) and permeability (PS) in ml/min/100 g were generated. The mean F, V, MTT and PS (Software-1) with VA-AIF and ICA-AIF were 8.93, 1.12, 16.3, 1.88 and 8.57, 1.19, 16.85 and 1.94, respectively. The reproducibility of the techniques was satisfactory, while the V and MTT values (in Software-1) and the F and V values (in Software-2) were dependent on the site of the AIF (p{>=}0.03 and p=0.02, respectively). The interobserver agreement was very good. The significant differences in measurements for a single patient (%) using Software-1/Software-2 were {+-}120%/110%, 90%/80%, 180% and 250%/130% for F, V, MTT and PS, respectively. Only F and PS values in the healthy tissue seemed to be interchangeable. Our results were in essential agreement with those derived by invasive measurements in animals. The cervical spine perfusion CT studies are feasible and reproducible. The present knowledge has to be validated with studies in spinal cord tumours in order to decide the usefulness of the perfusion CT in this field. (orig.)

  3. Evaluation of repeated measurements of radon-222 concentrations in well water sampled from bedrock aquifers of the Piedmont near Richmond, Virginia, USA: effects of lithology and well characteristics.

    Science.gov (United States)

    Harris, Shelley A; Billmeyer, Ernest R; Robinson, Michael A

    2006-07-01

    Radon (222Rn) concentrations in 26 ground water wells of two distinct lithologies in the Piedmont of Virginia were measured to assess variation in ground water radon concentrations (GWRC), to evaluate differences in concentrations related to well characteristics, lithology, and spatial distributions, and to assess the feasibility of predicting GWRC. Wells were sampled in accordance with American Public Health Association Method 7500 Rn-B, with modifications to include a well shaft profile analysis that determined the minimum purge time sufficient to remove the equivalent of one column of water from each well. Statistically significant differences in GWRC were found in the Trssu (1482 +/- 1711 pCi/L) and Mpg (7750 +/- 5188 pCi/L) lithologies, however, no significant differences were found among GWRC at each well over time. Using multiple regression, 86% of the variability (R2) in the GWRC was explained by the lithology, latitudinal class, and water table elevation of the wells. The GWRC in a majority of the wells studied exceed US Environmental Protection Agency designated maximum contaminant level and AMCL. Results support modifications to sampling procedures and indicate that, in previous studies, variations in GWRC concentrations over time may have been due in part to differences in sampling procedures and not in source water.

  4. An evaluation of the relationship between Gray’s revised RST and Eysenck’s PEN: distinguishing BIS and FFFS in Carver and White’s BIS/BAS scales

    OpenAIRE

    Heym, N; Ferguson, E; Lawrence, C.

    2008-01-01

    Recent revisions of Gray's Reinforcement Sensitivity Theory (RST) have important implications for self-report measures of approach and avoidance behaviours and how Gray's model relates to other personality models. In this paper, we examine the revised RST by comparing Carver and White's (1994) original one-factor solution of the BIS scale with two alternative two-factor solutions separating BIS-Anxiety and FFFS-Fear. We also examine the relationships between Eysenck's PEN and revised RST fact...

  5. Relative contributions of interface pressure, shear stress, and temperature on ischemic-induced, skin-reactive hyperemia in healthy volunteers: a repeated measures laboratory study.

    Science.gov (United States)

    Lachenbruch, Charlie; Tzen, Yi-Ting; Brienza, David; Karg, Patricia E; Lachenbruch, Peter A

    2015-02-01

    Although the primary risk factors for pressure ulcer development - pressure, shear, skin temperature, moisture, and friction - have been identified for decades, the relative contribution of each to this risk remains unclear. To confirm the results of and expand upon earlier research into the relative contributions of interface pressures, shear stress, and skin temperature among 4 healthy volunteers, a study involving 6 additional healthy 40- to 75-year-old volunteers was conducted and results of the 2 studies were pooled. All 3 variables (interface pressures, shear stress, and skin temperature) were systematically and randomly varied. In the prone position, volunteers each underwent 18 test conditions representing different combinations of temperature (28˚ C, 32˚ C, 36˚ C), pressure (8.0 and 13.3 kPa), and shear (0, 6.7, and 14.0 kPa) using a computer-controlled indenter applied to the sacrum for 20 minutes exerting weights of 100 g and 200 g to induce 0.98 N and 1.96 N of shear force, respectively. Each condition was tested twice, resulting in a total of 360 trials. Magnitude of postload reactive hyperemia as an index of ischemia was measured by laser Doppler flowmetry. Fixed effects regression models were used to predict 3 different indices of reactive hyperemic magnitude. Friedman tests were performed to compare the reactive hyperemia among 3 different skin temperatures or shear stresses under the same amount of localized pressure. In all regression models, pressure and temperature were highly significant predictors of the extent of reactive hyperemia (P pressure and shear stress, and the difference was more profound between 32˚ C and 36˚ C than between 28˚ C and 32˚ C. These results confirm that, in laboratory settings, temperature is an important factor in tissue ischemia. Additional studies examining the relative importance of pressure, shear, and temperature and potential effects of lowering temperature on tissue ischemia in healthy volunteers and

  6. Repetibilidade da mensuração de imagens das características de carcaça obtidas por ultrassonografia em fêmeas Nelore Repeatability of ultrasound image measurements of carcass traits in Nellore cattle

    Directory of Open Access Journals (Sweden)

    Maria Eugênia Zerlotti Mercadante

    2010-04-01

    Full Text Available Avaliou-se a repetibilidade da mensuração de imagens de ultrassom da área do músculo longissimus dorsi (AOL e das espessuras de gordura subcutânea do lombo (EGL e da garupa (EGG. Imagens de ultrassom tomadas no lombo (entre a 12ª e a 13ª costela e na garupa (entre os músculos gluteus medium e biceps femoris de novilhas Nelore de 14 a 22 meses de idade foram classificadas em aceitáveis, marginais e rejeitáveis. As imagens aceitáveis e marginais foram mensuradas duas vezes por três técnicos em diferentes níveis de treinamento. Foram estimadas as repetibilidades entre e dentro de técnicos por classe de qualidade da imagem, para determinação do efeito da qualidade da imagem e do técnico no valor absoluto da diferença entre a primeira e a segunda mensuração dessas características. A repetibilidade para as imagens aceitáveis foi maior que para imagens marginais, tanto entre como dentro de técnicos. Na análise da diferença absoluta entre a primeira e a segunda interpretação, foram significativos os efeitos de técnico para AOL e EGL e de classe de qualidade da imagem para AOL. Em geral, o técnico com maior experiência apresentou maiores valores de repetibilidade. É recomendável que a mensuração de imagens de animais de mesmo grupo contemporâneo seja feita por um único técnico.The repeatability of ultrasound image measurements of the longissimus dorsi muscle (AOL and of the rumpfat (EGG and backfat (EGL subcutaneous thickness was evaluated. Ultrasound images taken from the back (between 12th and 13th ribs and from the rump (between gluteus medium and biceps femoris muscles of Nelore heifers at 14 and 22 months of age were classified as acceptable, marginal and rejected. The acceptable and marginal images were measured twice by three technicians at different levels of training. It was estimated repeatabilities among and within technicians by class of image quality in order to determine effect of image quality and of

  7. Photophysical properties of endohedral amine-functionalized bis(phosphine) Pt(II) complexes as models for emissive metallacycles.

    Science.gov (United States)

    Pollock, J Bryant; Cook, Timothy R; Schneider, Gregory L; Lutterman, Daniel A; Davies, Andrew S; Stang, Peter J

    2013-08-19

    The photophysical properties of bis(phosphine) Pt(II) complexes constructed from 2,6-bis(pyrid-3-ylethynyl) aniline and 2,6-bis(pyrid-4-ylethynyl) aniline vary significantly, even though the complexes differ only in the position of the coordinating nitrogen. By capping the ligands with an aryl bis(phosphine) Pt(II) metal acceptor, the photophysical properties of the two isomeric systems were directly compared, revealing that the low-energy absorption and emission bands of the two systems were separated by 30 nm (1804 cm(-1)) and 39 nm (1692 cm(-1)), respectively. From the analysis of time-dependent density functional (TD-DFT) calculations and excited-state lifetime measurements, it was determined that the nature of the Pt-N bond in the HOMO and the sums of the radiative (k(rad)) and nonradiative (k(nr)) rate constants were significantly different in the two systems. As the dominant nonradiative decay pathway in aniline systems is relaxation from the triplet state through intersystem crossing (ISC), the difference in k(nr) can be ascribed to changes in ISC between isomers of the bis(phosphine) Pt(II)-capped 2,6-bis(pyrid-3-ylethynyl) aniline system. It was also determined that the photophysical properties of these capped systems can be altered by functionalizing the aryl capping ligand on the bis(phosphine) Pt(II) metal center, which perturbs the molecular orbitals involved in the observed optical transitions. In addition, an isoelectronic bis(phosphine) Pd(II)-capped system was prepared for comparison with the bis(phosphine) Pt(II) suite of complexes. The Pd(II) system showed significant changes in its low-energy absorption band, but preserved the characteristic emissive properties of its Pt(II) analogue with an even higher quantum yield.

  8. Crowding by a repeating pattern.

    Science.gov (United States)

    Rosen, Sarah; Pelli, Denis G

    2015-01-01

    Theinability to recognize a peripheral target among flankers is called crowding. For a foveal target, crowding can be distinguished from overlap masking by its sparing of detection, linear scaling with eccentricity, and invariance with target size.Crowding depends on the proximity and similarity of the flankers to the target. Flankers that are far from or dissimilar to the target do not crowd it. On a gray page, text whose neighboring letters have different colors, alternately black and white, has enough dissimilarity that it might escape crowding. Since reading speed is normally limited by crowding, escape from crowding should allow faster reading. Yet reading speed is unchanged (Chung & Mansfield, 2009). Why? A recent vernier study found that using alternating-color flankers produces strong crowding (Manassi, Sayim, & Herzog, 2012). Might that effect occur with letters and reading? Critical spacing is the minimum center-to-center target-flanker spacing needed to correctly identify the target. We measure it for a target letter surrounded by several equidistant flanker letters of the same polarity, opposite polarity, or mixed polarity: alternately white and black. We find strong crowding in the alternating condition, even though each flanker letter is beyond its own critical spacing (as measured in a separate condition). Thus a periodic repeating pattern can produce crowding even when the individual elements do not. Further, in all conditions we find that, once a periodic pattern repeats (two cycles), further repetition does not affect critical spacing of the innermost flanker.

  9. [(Dimethylaminomethyl]dimethylazanium bis(trifluoromethanesulfonylamide

    Directory of Open Access Journals (Sweden)

    Michael Hummel

    2016-10-01

    Full Text Available The title molecular salt, C5H15N2+·C2F6NO4S2−, was obtained by a proton transfer reaction between bis(trifluoromethanesulfonylamine and bis(dimethylaminomethane. In the crystal, the ions are linked by N—H...O=S hydrogen bonds, and these units are linked by C—H...O hydrogen bonds, forming sheets parallel to the bc plane. The crystal was refined as a non-merohedral twin with a BASF factor of 0.316 (1.

  10. Repeatability of peripheral aberrations in young emmetropes.

    Science.gov (United States)

    Baskaran, Karthikeyan; Theagarayan, Baskar; Carius, Staffan; Gustafsson, Jörgen

    2010-10-01

    The purpose of this study is to assess the intrasession repeatability of ocular aberration measurements in the peripheral visual field with a commercially available Shack-Hartmann aberrometer (complete ophthalmic analysis system-high definition-vision research). The higher-order off-axis aberrations data in young healthy emmetropic eyes are also reported. The aberrations of the right eye of 18 emmetropes were measured using an aberrometer with an open field of view that allows peripheral measurements. Five repeated measures of ocular aberrations were obtained and assessed in steps of 10° out to ±40° in the horizontal visual field (nasal + and temporal -) and -20° in the inferior visual field. The coefficient of repeatability, coefficient of variation, and the intraclass correlation coefficient were calculated as a measure of intrasession repeatability. In all eccentric angles, the repeatability of the third- and fourth-order aberrations was better than the fifth and sixth order aberrations. The coefficient of variation was coefficient was >0.90 for the third and fourth order but reduced gradually for higher orders. There was no statistical significant difference in variance of total higher-order root mean square between on- and off-axis measurements (p > 0.05). The aberration data in this group of young emmetropes showed that the horizontal coma (C(3)(1)) was most positive at 40° in the temporal field, decreasing linearly toward negative values with increasing off-axis angle into the nasal field, whereas all other higher-order aberrations showed little or no change. The complete ophthalmic analysis system-high definition-vision research provides fast, repeatable, and valid peripheral aberration measurements and can be used efficiently to measure off-axis aberrations in the peripheral visual field.

  11. PCl5 as a mild and efficient catalyst for the synthesis of bis(indolylmethanes and di-bis(indolylmethanes

    Directory of Open Access Journals (Sweden)

    Alireza Hasaninejad

    2008-12-01

    Full Text Available Phosphorus pentachloride (PCl5 can efficiently catalyze the condensation of indoles with aldehydes as well as ketones at room temperature to afford bis(indolylmethanes and di-bis(indolylmethanes in high yields and short reaction times.

  12. Single-molecule kinetics and footprinting of DNA bis-intercalation: the paradigmatic case of Thiocoraline

    Science.gov (United States)

    Camunas-Soler, Joan; Manosas, Maria; Frutos, Silvia; Tulla-Puche, Judit; Albericio, Fernando; Ritort, Felix

    2015-01-01

    DNA bis-intercalators are widely used in molecular biology with applications ranging from DNA imaging to anticancer pharmacology. Two fundamental aspects of these ligands are the lifetime of the bis-intercalated complexes and their sequence selectivity. Here, we perform single-molecule optical tweezers experiments with the peptide Thiocoraline showing, for the first time, that bis-intercalation is driven by a very slow off-rate that steeply decreases with applied force. This feature reveals the existence of a long-lived (minutes) mono-intercalated intermediate that contributes to the extremely long lifetime of the complex (hours). We further exploit this particularly slow kinetics to determine the thermodynamics of binding and persistence length of bis-intercalated DNA for a given fraction of bound ligand, a measurement inaccessible in previous studies of faster intercalating agents. We also develop a novel single-molecule footprinting technique based on DNA unzipping and determine the preferred binding sites of Thiocoraline with one base-pair resolution. This fast and radiolabelling-free footprinting technique provides direct access to the binding sites of small ligands to nucleic acids without the need of cleavage agents. Overall, our results provide new insights into the binding pathway of bis-intercalators and the reported selectivity might be of relevance for this and other anticancer drugs interfering with DNA replication and transcription in carcinogenic cell lines. PMID:25690887

  13. 超高分辨率OCT角膜上皮厚度自动测量的重复性研究%Study of repeatability of corneal epithelium thickness profiles automatically measured by ultra -high resolution OCT system

    Institute of Scientific and Technical Information of China (English)

    徐肃仲; 叶欣杰; 许哲; 杨纯; 沈梅晓

    2013-01-01

    目的:研究基于自动分层算法的超高分辨率谱域 OCT ( UHR-OCT)用于角膜上皮厚度测量的重复性。  方法:使用自行搭建的UHR-OCT系统采集18例健康受试者(年龄23.2±0.9岁)左眼的图像,应用一种基于轴向梯度信息和最短路径的分层算法对得到的SD-OCT图像进行边界探测获取角膜上皮厚度。  结果:自动与手动的上皮分层的位置有很好的相关性(P>0.05,配对t检验)。自动算法获取的6 mm范围平均上皮厚度为52.1±2.1μm,范围从50.3±1.8μm 到53.2±2.4μm,与手动分层之间的角膜上皮厚度差异为0.4±0.3μm。UHR-OCT自动算法重复测量上皮厚度的组内相关系数ICC和可重复性系数CoR分别为0.90±0.05,1.44±0.01μm。  结论:对于超高分辨率OCT,自动分层方法在角膜上皮厚度测量中有着很好的准确性和可重复性。%AIM:To assess the repeatability of thickness profiles of corneal epithelium produced by aautomatic hierarchic algorithm that was applied to images obtained by a custom-built ultra-high resolution OCT ( UHR-OCT ) system. METHODS:Eighteen left eyes of 18 subjects (23.2±0.9) years;mean age±standard deviation) were imaged twice on non-consecutive days by a custom-built ultra-high resolution OCT ( UHR -OCT ) system. A hierarchic algorithm based on the axial gradient information and a shortest path search was developed to measure the corneal epithelial thickness profiles from the SD-OCT images. RESULTS: There was good correlation between theautomatic and manual hierarchy positions of the epithelium ( p >0.05, paired t -test ). The average epithelial thickness of the 6mm central corneal region determined by the automatic hierarchic algorithm was 52.1±2.1μm, ranging from 50.3 ±1.8μm to 53.2 ±2.4μm along the horizontal meridian. The epithelial thickness differences between automatic and manual hierarchy by the UHR-OCT systems were 0.4 ±0

  14. Repeatability of Cryogenic Multilayer Insulation

    Science.gov (United States)

    Johnson, W. L.; Vanderlaan, M.; Wood, J. J.; Rhys, N. O.; Guo, W.; Van Sciver, S.; Chato, D. J.

    2017-01-01

    Due to the variety of requirements across aerospace platforms, and one off projects, the repeatability of cryogenic multilayer insulation has never been fully established. The objective of this test program is to provide a more basic understanding of the thermal performance repeatability of MLI systems that are applicable to large scale tanks. There are several different types of repeatability that can be accounted for: these include repeatability between multiple identical blankets, repeatability of installation of the same blanket, and repeatability of a test apparatus. The focus of the work in this report is on the first two types of repeatability. Statistically, repeatability can mean many different things. In simplest form, it refers to the range of performance that a population exhibits and the average of the population. However, as more and more identical components are made (i.e. the population of concern grows), the simple range morphs into a standard deviation from an average performance. Initial repeatability testing on MLI blankets has been completed at Florida State University. Repeatability of five GRC provided coupons with 25 layers was shown to be +/- 8.4 whereas repeatability of repeatedly installing a single coupon was shown to be +/- 8.0. A second group of 10 coupons have been fabricated by Yetispace and tested by Florida State University, through the first 4 tests, the repeatability has been shown to be +/- 16. Based on detailed statistical analysis, the data has been shown to be statistically significant.

  15. Vaporization behavior of tetraoctylphosphonium bis(2-ethylhexyl)phosphate ionic liquid

    Science.gov (United States)

    McMurray, J. W.; Zhou, Y.; Luo, H. M.; Qu, J.

    2017-01-01

    The equilibrium vapor pressures, pe, of the ionic liquid tetraoctylphosphonium bis(2-ethylhexyl)phosphate ([P8888][DEHP]) over the temperature range 409-495 K were determined for the first time using mass loss Knudsen effusion. The pe versus temperature relationship compares well to 1-methyl-3-octylimidazolium bis(trifluoromethylsulfonyl)imide ([C8mim][NTf2]) but is lower than that of 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([C2mim][NTf2]) when measured using the same technique. The discrepancies between the pe determined in this work for [C8mim][NTf2] and [C2mim][NTf2] with previous studies is discussed. The enthalpy and entropy of vaporization for all three fluids are estimated from the Clasius-Clapeyron relation.

  16. Monitoring sleep depth: analysis of bispectral index (BIS) based on polysomnographic recordings and sleep deprivation.

    Science.gov (United States)

    Giménez, Sandra; Romero, Sergio; Alonso, Joan Francesc; Mañanas, Miguel Ángel; Pujol, Anna; Baxarias, Pilar; Antonijoan, Rosa Maria

    2017-02-01

    The assessment and management of sleep are increasingly recommended in the clinical practice. Polysomnography (PSG) is considered the gold standard test to monitor sleep objectively, but some practical and technical constraints exist due to environmental and patient considerations. Bispectral index (BIS) monitoring is commonly used in clinical practice for guiding anesthetic administration and provides an index based on relationships between EEG components. Due to similarities in EEG synchronization between anesthesia and sleep, several studies have assessed BIS as a sleep monitor with contradictory results. The aim of this study was to evaluate objectively both the feasibility and reliability of BIS for sleep monitoring through a robust methodology, which included full PSG recordings at a baseline situation and after 40 h of sleep deprivation. Results confirmed that the BIS index was highly correlated with the hypnogram (0.89 ± 0.02), showing a progressive decrease as sleep deepened, and an increase during REM sleep (awake: 91.77 ± 8.42; stage N1: 83.95 ± 11.05; stage N2: 71.71 ± 11.99; stage N3: 42.41 ± 9.14; REM: 80.11 ± 8.73). Mean and median BIS values were lower in the post-deprivation night than in the baseline night, showing statistical differences for the slow wave sleep (baseline: 42.41 ± 9.14 vs. post-deprivation: 39.49 ± 10.27; p = 0.02). BIS scores were able to discriminate properly between deep (N3) and light (N1, N2) sleep. BIS values during REM overlapped those of other sleep stages, although EMG activity provided by the BIS monitor could help to identify REM sleep if needed. In conclusion, BIS monitors could provide a useful measure of sleep depth in especially particular situations such as intensive care units, and they could be used as an alternative for sleep monitoring in order to reduce PSG-derived costs and to increase capacity in ambulatory care.

  17. Repeated Measurement of Divers’ Word Fluency.

    Science.gov (United States)

    1987-04-01

    function (Fillskov & Boll, -V 1981). One type of test with clinical significance reflects Word Fluency (Borkowski, Benton & Spreen, 1967; Lezak, 1983). Word...Fluency is "the facility to produce words that fit one or more structural, phonetic , or orthographic restrictions that are not relevant to the meaning...toxic chemical exposure (Anger, 1984) and closed head injury (Borkowski et al, 1967). Word Fluency reflects mild linguistic deficits in expressive speech

  18. Electronically asymmetric bis(porphyrin) sandwich complexes

    Energy Technology Data Exchange (ETDEWEB)

    Girolami, G.S.; Gorlin, P.A.; Suslick, K.S. [Univ. of Illinois, Urbana, IL (United States)

    1994-02-16

    Bis(porphyrin)metal(IV) complexes (M(porph){sub 2}) have been extensively studies in recent years due to their structural, chemical, and spectroscopic similarity to the {open_quotes}special pair{close_quotes} found in the reaction center of photosynthetic bacteria. Strong interactions arise in the bis(porphyrin) complexes due to the short inter-porphyrin separation (< 3 {angstrom}), which results in properties not seen in mono(porphyrin) analogs. For example, the bis(porphyrin) complexes are considerably easier to oxidize than analogous mono(porphyrin) species, and the M(porph){sub 2{sup n+}} cations (n = 1,2) exhibit near-IR absorptions not found in simple mono(porphyrin)cations. As part of the authors continuing effort to understand the factors that govern the electronic structures of bis(porphyrin) supermolecules, the authors now describe the synthesis of a series of zirconium sandwich complexes. Introduction of electron-withdrawing or -donating groups on the {beta}-pyrrole position considerably affects the electronic properties of these molecules without altering their steric parameters. Thus, peripheral substitution allows modification of the inter-porphyrin {pi} interactions while keeping the inter-porphyrin separation constant. Previous studies have changed the identity of the central metal, but the electronic structure and the interplanar distance could not be varied independently.

  19. Different remifentanil doses in rapid sequence anesthesia induction: BIS monitoring and intubation conditions.

    Science.gov (United States)

    Alanoğlu, Zekeriyya; Tolu, Sinem; Yalçın, Saban; Batislam, Yeşim; Özatamer, Oya; Tüzüner, Filiz

    2013-01-01

    The aim of this prospective, randomized, double blind trial was to investigate the effects of two different doses of remifentanil on bispectral index (BIS) values and intubation conditions in a simulated model of rapid sequence anesthesia induction (RSAI). 54 ASA I-II adult patients undergoing elective surgery were randomly allocated to two groups. After preoxygenation for 3 minutes, induction and tracheal intubation was performed in a 300 head-up position. Group I (n=26) and Group II (n=28) received a 1 µg/kg or 0.5 µg/kg bolus of remifentanil, respectively, over 30 seconds. Propofol was the induction agent. 1 mg/kg of rocuronium was used in all patients. Patients were intubated 60 s after administration of the muscle relaxant. Hemodynamic data and BIS scores were obtained before induction (baseline), after induction, at intubation and at 1, 3, 5 and 10 minutes following intubation. Intubation conditions were scored with a standard scoring system. The hemodynamic variables at all the measurement intervals and the area under the hemodynamic variable-time curves were similar among the groups. There was no difference among the groups for BIS measurements. Moreover, the mean area under the BIS-time curve for Group I (300±45cm2) was comparable to Group II (315±49cm2) (p=0.432). The mean total intubation condition score (maximum 14 points) in Group I (12.6±1.67) was higher than Group II (10.3±4.79) (p=0.030). 1 µg/kg of remifentanil compared to 0.5 µg/kg of remifentanil provides similar hemodynamic profiles and BIS scores, but 1 µg/kg of remifentanil was associated with superior endotracheal intubation conditions. According to this study design and medications used, a relation between BIS scores and intubation conditions couldn't be demonstrated.

  20. Quantum Key Distribution over Probabilistic Quantum Repeaters

    CERN Document Server

    Amirloo, Jeyran; Majedi, A Hamed

    2010-01-01

    A feasible route towards implementing long-distance quantum key distribution (QKD) systems relies on probabilistic schemes for entanglement distribution and swapping as proposed in the work of Duan, Lukin, Cirac, and Zoller (DLCZ) [Nature 414, 413 (2001)]. Here, we calculate the conditional throughput and fidelity of entanglement for DLCZ quantum repeaters, by accounting for the DLCZ self-purification property, in the presence of multiple excitations in the ensemble memories as well as loss and other sources of inefficiency in the channel and measurement modules. We then use our results to find the generation rate of secure key bits for QKD systems that rely on DLCZ quantum repeaters. We compare the key generation rate per logical memory employed in the two cases of with and without a repeater node. We find the cross-over distance beyond which the repeater system outperforms the non-repeater one. That provides us with the optimum inter-node distancing in quantum repeater systems. We also find the optimal exci...

  1. Nervus medianus evoked potentials and bispectral index during repeated transitions from consciousness to unconsciousness.

    Science.gov (United States)

    Rundshagen, I; Mast, J; Mueller, N; Pragst, F; Spies, C; Cortina, K

    2008-09-01

    We investigated the relationship between median nerve somatosensory evoked potentials (SSEPs) and the bispectral index (BIS) during alternating periods of consciousness and propofol-induced unconsciousness. Loss of consciousness (LOC) was repetitively induced by bolus injections of propofol in 24 patients undergoing elective surgery in spinal anaesthesia. SSEP and the BIS were recorded during LOC and recovery of consciousness (ROC). The level of consciousness was clinically assessed by the observer's assessment of alertness/sedation scale. Propofol venous plasma concentrations were measured simultaneously. At LOC, all SSEPs latency components were prolonged (P or = 45 ms were smaller (P=0.008) and the BIS values were lower (Plevels during ROC. Regression analyses revealed that the SSEP components (five latencies and five amplitudes) explained 33% of the variance when predicting ROC; the BIS explained 12%. The combination of SSEP and BIS explained 37% of variance in this patient sample. Propofol venous plasma concentration was 1.2 (0.8) microg ml(-1) during LOC and 0.4 (0.5) microg ml(-1) during ROC. The present results indicate the usefulness of combining variables of the evoked and spontaneous EEG to measure different levels of consciousness, because the SSEP provide additional information beyond the BIS. Inter-individual variability of all the EEG variables limits their predictive potency of ROC after propofol infusion.

  2. Halogen-free bis(imidazolium)/bis(ammonium)-di[bis(salicylato)borate] ionic liquids as energy-efficient and environmentally friendly lubricant additives.

    Science.gov (United States)

    Gusain, Rashi; Gupta, Piyush; Saran, Sandeep; Khatri, Om P

    2014-09-10

    Bis(imidazolium)- and bis(ammonium)-di[bis(salicylato)borate] ionic liquids with variable alkyl chain and cyclic ring structures, were synthesized and then evaluated them as potential lubricant additives. The copper strip test results revealed noncorrosive properties of these ionic liquids. Introduction of halogen content in bis(imidazolium) ionic liquid by replacement of bis(salicylato)borate (BScB) anion with hexafluorophosphate (PF6(-)), severely corroded the copper strip. Thermogravimetric results showed that bis(imidazolium) ionic liquids exhibited higher thermal stability than bis(ammonium) ionic liquids owing to compact structure provided by imidazolium rings, higher intermolecular interactions, smaller free volume and low steric hindrance. The lubrication properties of these ionic liquids as additives to synthetic lubricant poly(ethylene) glycol (PEG 200) were evaluated for steel balls. Results showed that bis(ammonium)- and bis(imidazolium)-(BScB)2 ionic liquids as additives significantly reduced both friction coefficient and wear of PEG 200. The structure of cations, particularly the variation in substituted alkyl chain length monitored the degree of reduction in friction and wear. The excellent lubrication properties were attributed to the formation of adsorbed tribo-thin film and tribochemical product during the tribo-contact. Being halogen-, phosphorus-, and sulfur-free, these ionic liquids (a) protects contact surfaces from tribo-corrosive events, (b) reduces the friction and wear, and (c) keep environment green and clean.

  3. Formation and Characterization of Mixed Crystals Based on Bis (ThioureaCadmium Chloride and Bis (ThioureaCadmium Iodide

    Directory of Open Access Journals (Sweden)

    I.S. Prameela Kumar

    2014-07-01

    Full Text Available Bis(thioureacadmium chloride(BTCC and bis(thioureacadmium iodide (BTCI are metal complexes of thiourea having better nonlinear optical properties than KH2PO4. An attempt has been made in the present study to form mixed crystals based on BTCC and BTCI (even though their crystal lattices mismatch from aqueous solutions, the precursors mixed in proper proportions. A total of seven (including the end members crystals were formed by the free evaporation method and characterized chemically, structurally, thermally, optically and electrically. The X-ray diffraction measurements indicate that (BTCCX(BTCI1-X crystals with x=1.0,0.8 and 0.6 are orthorhombic in structure with space group Pmn21 and that with x=0.5, 0.4, 0.2 and 0.0 are monoclinic in structure with space group P21/c. All the grown crystals are found to be thermally stable up to 215 °C and possessing wide optical transmission window (300-900 nm which is suitable for NLO applications. The electrical measurements indicate that the grown crystals exhibit a normal dielectric behavior. The results obtained in the present study indicate that mixed crystals can be formed from the isomorphous precursors directly even though the end member’s crystals have lattice mismatching.

  4. Measurement of Q{sub {beta}} values of neutron-rich Tc to Pd isotopes in the mass range A=110 to A=117; Messung von Q{sub {beta}}-Werten neutronenreicher Tc- bis Pd-Isotope im Massenbereich A=110 bis A=117

    Energy Technology Data Exchange (ETDEWEB)

    Kloeckl, Ingo

    2008-06-15

    The present work describes the measuring of Q{sub {beta}} values of {beta}-instable isotopes of Tc, Ru, Rh and Pd. The mass range A=110 to 117 comprises neutron-rich, short-living isotopes. Due to their small (fission) abundances, few data are known, especially regarding level schemes or gamma radiation. The proton-induced fission and a fast online mass separation was used to produce these nuclides in the IGISOL facility located in Jyvaeskylaein Finland. The {beta},{gamma},X coincidence apparatus used during the experiments allows measuring Q{sub {beta}} values as well as {gamma},X coincidences. The latter represent the basic input data for a calculation of Q{sub {beta}} values out of {beta},{gamma} coincidences. It is so possible to examine nuclides with incomplete level schemes; similarly, these level schemes can be extended using beta,gamma coincidence data. Twelve Q{sub {beta}} values of neutron-rich Tc to Pd isotopes could be determined, yielding nuclear masses, mass defects and neutron separation energies. Eight of them were determined for the first time; another one could be confirmed. For three more, the error of earlier values could be decreased by a factor of nearly ten. The resulting data are of interest for the review of nuclear mass models, they represent also input in astrophysical network calculations. (orig.)

  5. Hybrid Intelligent System to Perform Fault Detection on BIS Sensor During Surgeries

    Science.gov (United States)

    Casteleiro-Roca, José-Luis; Calvo-Rolle, José Luis; Méndez Pérez, Juan Albino; Roqueñí Gutiérrez, Nieves; de Cos Juez, Francisco Javier

    2017-01-01

    This paper presents a new fault detection system in hypnotic sensors used for general anesthesia during surgery. Drug infusion during surgery is based on information received from patient monitoring devices; accordingly, faults in sensor devices can put patient safety at risk. Our research offers a solution to cope with these undesirable scenarios. We focus on the anesthesia process using intravenous propofol as the hypnotic drug and employing a Bispectral Index (BISTM) monitor to estimate the patient’s unconsciousness level. The method developed identifies BIS episodes affected by disturbances during surgery with null clinical value. Thus, the clinician—or the automatic controller—will not take those measures into account to calculate the drug dose. Our method compares the measured BIS signal with expected behavior predicted by the propofol dose provider and the electromyogram (EMG) signal. For the prediction of the BIS signal, a model based on a hybrid intelligent system architecture has been created. The model uses clustering combined with regression techniques. To validate its accuracy, a dataset taken during surgeries with general anesthesia was used. The proposed fault detection method for BIS sensor measures has also been verified using data from real cases. The obtained results prove the method’s effectiveness. PMID:28106793

  6. Bis(L-cysteinato)gold(I): chemical characterization and identification in renal cortical cytoplasm.

    Science.gov (United States)

    Shaw, C F; Schmitz, G; Thompson, H O; Witkiewicz, P

    1979-07-01

    L-Cysteinatogold(I) was prepared by the reaction of L-cysteine with KAuBr4 in acidic media and its solubility determined from pH 4 to 10. The solubility at pH 7.4 and 37 degrees C is 1 microM. In the presence of excess cysteine, the solubility increases because of formation of bis(L-cysteinato)gold(I). The equilibrium-constant for formation of the bis complex is 2.1 +/- 0.4 X 10(-3), which at pH 7.4 CORRESPONDs to an apparant formation constant of 4.4 X10(4). The formation of the bis adduct was confirmed by chromatographic separation of the products of the reaction between [35S]-L-cysteine and Na2AuTM. This complex elutes with Kav = 1.15 which allows it to be distinguished from other gold thiolates that might form in vivo. The bis(cysteinato)gold(I) complex is shown to be present in kidney cytosol isolated from rats given Na2AuTM in vivo. When additional cysteine is added to the cytosol in vitro, the peak at 1.15 is increased, but if glutathione is added, the low molecular weight gold elutes at Kav = 1.00, which is taken as evidence for the existence of bis(cysteinato)gold(I) in the cytosol preparation. The amount of gold present as bis(cysteinato)gold(I) after 4 different dose schedules has been measured and found to increase with the total cytosol gold concentration. L-Cysteinatogold(I) does not dissolve in the presence of bovine serum albumin to form an adduct.

  7. Verificação da prótese auditiva realizada face a face e via teleconsulta: medidas repetidas Telecounselling and face to face hearing aid verification: repeated measures

    Directory of Open Access Journals (Sweden)

    Deborah Viviane Ferrari

    2012-12-01

    Full Text Available OBJETIVO: avaliar as medidas repetidas da resposta de ressonância da orelha externa sem (REUR e com uso de amplificação (REAR e o ganho de inserção (REIG, realizados face a face e via teleconsulta. MÉTODO: estudo prospectivo longitudinal. Foram realizadas quatro repetições da REUR, REAR e REIG (com estímulo speech noise apresentado em 65 dB NPS e 0º azimute em 19 orelhas de adultos ouvintes normais, via face a face (F e teleconsulta síncrona por controle remoto de aplicativo (T e vídeo interativo. O software Polycom PVX foi utilizado para compartilhamento e transmissão de áudio e vídeo. A conexão foi realizada via LAN (Local Area Network USP na velocidade de 384 kbps Foi calculado o erro causal (Dalhberg entre as quatro medidas para frequências de 250 a 8000 Hz. RESULTADOS: os erros casuais entre as medidas F e T foram muito semelhantes, sendo maiores nas frequências acima de 4 kHz. As diferenças e variações entre as medidas F e T estavam dentro da magnitude de variabilidade do procedimento de medidas com microfone sonda. CONCLUSÃO: as medidas com microfone sonda via teleconsulta fornece resultados confiáveis e similares aos obtidos pelo procedimento padrão.PURPOSE: to evaluate the repeated measurements of the real ear unaided response (REUR, real ear aided response (REAR and insertion gain (REIG conducted as face to face (F and via telecounselling (T. METHOD: longitudinal prospective study. Four measures of REUR, REAR and REIG (carried out with speech noise stimulus presented at 65 dB SPL at 0° azimuth were obtained in 19 ears in normal hearing adults, face to face and via synchronous telecounsellings with remote control of the real ear equipment and interactive video. Polycom PVX software was used for desktop sharing and video and audio transmission. The Loca Area Network (LAN USP was used for the connection (transmission rate: 384 kbps. Dahlberg’s casual errors were calculated for obtaining the measures for

  8. Copper dynamics in doped metal-bis(histidine) complexes.

    Science.gov (United States)

    Colaneri, Michael J; Vitali, Jacqueline

    2014-07-03

    Electron paramagnetic resonance (EPR) temperature-dependent measurements were undertaken on three Cu(II)-doped metal-histidine complexes to assess copper site dynamic behavior. Previous single-crystal EPR analysis on two of these, zinc d,l-histidine pentahydrate (ZnDLH) and bis(l-histidinato)cadmium dihydrate (CdLH), found that doped Cu(2+) can be modeled as hopping between two neighboring conformational states, with a temperature-dependent rate becoming large enough at room temperature to produce an "averaged" spectrum. By comparing spectra from their powdered form, we show that Cu(2+) doped into a third system, Cd(2+)-d,l-histidine (CdDLH), also exhibits temperature-dependent EPR with features indicating a similar motional-averaging process. In addition, the change of g and copper hyperfine parameters from low to high temperature for CdDLH resembles that in ZnDLH, whereas the change in these parameters for CdLH is like that found in a fourth copper-doped system, zinc l-histidine dihydrate (ZnLH). Taken together, these results suggest that averaging motion between neighboring copper sites is common in metal-bis(histidine) compounds. More detailed studies on biological models are thus warranted, especially because they reveal unique relationships between structure, dynamic processes, and stability and can lead to a better understanding of the role played by site flexibility in copper proteins.

  9. 重复测试和不同性别对小鼠旷场行为的影响%Repeated Measurement and Sex for the Behavior in Open Field in Mice

    Institute of Scientific and Technical Information of China (English)

    陈超杰; 钟志凤; 俞昌喜

    2014-01-01

    OBJECTIVE To study the effect on the locomotory activity and anxiety-like behavior of laboratory mice by both factors of repeated measurement and sex.METHODS The total distance traveled ,total mean velocity , total parallel index,the percentage of distance in center zone ,the mean velocity in center zone ,the center zone en-tries,the percentage of time spent in center zone and the parallel index in center zone of the female and male mice for 5 minutes were recorded and analyzed in open field test by animal video tracking analysis system ,once a day for 3 days.RESULTS In the open field test ,the indexes of the total distance traveled ,total mean velocity ,total parallel index ,the percentage of distance in center zone ,the mean velocity in center zone ,the center zone entries ,the percent-age of time spent in center zone and the parallel index in center zone in mice showed the downtrend as the measure -ment numbers were increasing ( P0.05 ).However ,as repeating the tests ,the downtrend of these in male mice were seemly more significant than female mice ,especially in the third time measurement ,in which the mean velocity ( P<0.05 ) and parallel index ( P<0.01 ) in center zone were lower than the ones in female mice ,respectively.CONCLUSION The repeated measurement inferences the locomotory activity and interrupted the anxiety state of mice.Sex of mice does not make the behavior in open field different at the first time ,but the repeated measurement seemly more signifi-cantly affect the locomotory activity of the male mice than the female.%目的:研究重复测试和不同性别两个因素对小鼠在旷场试验中自主行为活动和焦虑行为的影响。方法通过动物视频行为分析系统,分别记录和分析雌雄小鼠5 min内在旷场中的总路程、总体平均速度、总体平行指数、中央区的路程占总路程的比例、中央区的平均速度、中央区进入次数、中央区停留时间占整体测试时间的比例和中

  10. Metal-biradical chains from a high-spin ligand and bis(hexafluoroacetylacetonato)copper(II).

    Science.gov (United States)

    Rajadurai, Chandrasekar; Enkelmann, Volker; Ikorskii, Vladimir; Ovcharenko, Victor I; Baumgarten, Martin

    2006-11-27

    The synthesis, X-ray crystal structure, and magnetic studies of a rare example of organic/inorganic spin hybrid clusters extended in infinite ladder-type chain [Cu(C5F6HO2)2]7(C35H35N5O4)2 ([Cu(hfac)2]7(pyacbisNN)2, 2) formed by the reaction of a high spin nitronylnitroxide biradical C35H35N5O4 (pyacbisNN, 1) and bis(hexafluroacetylacetonate)copper(II) = Cu(hfac)2 are described. Single-crystal X-ray structure analysis revealed the triclinic P1 space group of 2 with the following parameters: a = 10.6191(4) A, b = 19.6384(7) A, c = 21.941(9) A, alpha = 107.111(7) degrees, beta = 95.107(8) degrees, gamma = 94.208(0) degrees , Z = 2. Each repeating unit in 2 carries a centrosymmetric cyclic six spin and a linear five spin cluster with four different copper coordination environments having octahedral and square planar geometries. These clusters are interconnected to form infinite chains which are running along the crystallographic b axis. The magnetic measurements show nearly paramagnetic behavior with very small variations over a large temperature range. The magnetic properties are thus result of complex competitions of many weak ferro- and antiferromagnetic interactions, which appear as small deviations from quite linear mu(eff) vs T dependence at low temperature. At high temperature (300-14 K), antiferromagnetic behavior dominates a little, while at very low temperature (14-2 K), a small increase of mu(eff) was observed. The magnetic susceptibility data are described by the Curie-Weiss law [chi = C/(T - theta)] with the optimal parameters C = 4.32 +/- 0.01 emuK/mol and theta = - 0.6 +/- 0.3 K, where C is the Curie constant and theta is the Weiss temperature.

  11. Inductive effects on benzene solvent shifts in PMR spectra of (acetylacetonato)-organoantimony(V) and bis(acetylacetonato)organotin(IV) compounds

    NARCIS (Netherlands)

    Mackor, A.; Meinema, H.A.

    1972-01-01

    PMR benzene solvent shifts (Formula Presented.) and (Formula Presented.) have been measured for acetylacetonato protons of hexacoordinate (acetylacetonato)organoantimony(V) and bis(acetylacetonato)organotin(IV) compounds. The observed values correlate better with the inductive effect of substituents

  12. Optimal and safe treatment of spider leg veins measuring less than 1.5 mm on skin type IV patients, using repeated low-fluence Nd:YAG laser pulses after polidocanol injection.

    Science.gov (United States)

    Moreno-Moraga, Javier; Hernández, Esteban; Royo, Josefina; Alcolea, Justo; Isarría, M Jose; Pascu, Mihail Lucian; Smarandache, Adriana; Trelles, Mario

    2013-05-01

    Treatment of micro-veins of less than 1.5 mm with laser and with chemical sclerosis is technically challenging because of their difficulty to remedy. Laser treatment is even more difficult when dark phototypes are involved.Three groups of 30 patients each, skin type IV, and vessels measuring less than 1.5 mm in diameter, were enrolled for two treatment sessions 8 weeks apart: group A, polidocanol (POL) micro-foam injection; group B, Nd:YAG laser alone; and group C, laser after POL injection. Repeated 8-Hz low-fluence pulses, moving the hand piece over a 3-cm vein segment with an average of five laser passes maximum and with a total time irradiation of 1 s were used. Sixteen weeks after the second treatment, statistically, degree of clearance after examining photographs and patients satisfaction index, plotted on a visual analogue scale and comparing results of all three groups, results were significantly better for group C (p<0.0001). No significant differences in complications were noticed between the three groups. Efficacy of combining POL and laser proved safe and satisfactory in 96 % of patients using low-fluence laser pulses with a total cumulative energy in the 3 cm venous segment, lower than that of conventional treatment. Very few and transient complications were observed. POL foam injection followed by laser pulses is safe and efficient for vein treatment in dark-skinned patients.

  13. Talking about the cause of the failures to prohibit repeatedly for prostitution or whoring and its measures%当前卖淫嫖娼屡禁不止的原因及对策

    Institute of Scientific and Technical Information of China (English)

    冯文林

    2011-01-01

    The author was talking about the characteristics of the prostitution and whoring in current, setting forth the cause of the failures to prohibit repeatedly for the prostitution and whoring. At last, the author was putting forward to the controlling measur%随着社会主义市场经济的快速发展,许多人的思想观念受市场经济消极因素和西方资本主义腐朽思想及生活方式的影响进一步加深,卖淫嫖娼行为逐年增多,已经成为一种广泛的社会丑恶现象,严重影响到当前社会治安秩序的和谐稳定,引发一系列的问题,其危害性不可低估。政府和公安机关要加大对卖淫嫖娼行为的查处打击力度,研究如何才能减少滋生卖淫嫖娼的各种因素,加强预防和正面宣传,有针对性的开展治理,净化社会环境,维护社会和谐稳定。

  14. Synthesis, Characterization and Properties of Bis{oxo-bis[heteroaromatic carboxylatodibenzyltin(Ⅳ)]} and Crystal Structure of Bis{oxo-bis[2-furylcarboxylatodibenzyltin(Ⅳ)]}

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    A series of bis{oxo-bis[heteroaromatic carboxylatodibenzyltin(Ⅳ)]} complexes {[(PhCH2)2Sn*(O2CR)]2O}2[where R=2-furyl, 2-(2-furyl)vinyl, 2-(5-tert-butyl)furyl, 2-thiophenyl, 2-pyridinyl, 3-pyridinyl, 4-pyridinyl, 3-indolyl, 3-indolylmethyl, 3-indolylpropyl] was synthesized by the reactions of heteroaromatic carboxylic acids with dibenzyltin(Ⅳ) oxide. All the complexes were characterized by elemental analysis, IR, and NMR spectra. The complexes were tested against two human tumour cell lines: MCF-7 and WiDr. The results show that they have higher activities in vitro. The crystal structure of bis{oxo-bis[2-furylcarboxylatodibenzyltin(Ⅳ)]}(1) was determined by X-ray diffraction. The crystal belongs to monoclinic space group P21/n, a=1.6641(2) nm, b=1.25073(18) nm, c=1.7193(3) nm, β=101.951(2)°, Z=2, R1=0.0446, wR2=0.1100. Complex 1 is of a centrosymmetric dimer structure with a four-membered central endo-cyclic Sn2O2 unit in which the bridged oxygen atoms are tri-coordinated. Each bridged oxygen atom also connects with an exo-cyclic tin atom. The tin atoms are six-coordinated and have a coordination geometry of a distorted octahedron. The exo-cyclic tin atoms are five-coordinated and have a coordination geometry of a monocapped trigonal bipyramid with a very similarly distorted mode. Four carboxylate ligands are divided into two types. The two of the four carboxylate ligands are bidentate and bridged to each pair of exo- and endo-cyclic tin atoms by using both the oxygen atoms. The other two are monodentate and bridged to each pair of exo- and endo-cyclic tin atoms but each utilizes one O atom only.

  15. [N,N-Bis(diphenylphosphinoisopropylamine]dibromidonickel(II

    Directory of Open Access Journals (Sweden)

    2009-03-01

    Full Text Available The title compound, [NiBr2(C27H27NP2], was synthesized by the reaction of NiBr2(dme (dme is 1,2-dimethoxyethane with N,N-bis(diphenylphosphinoisopropylamine in methanol/tetrahydrofuran. The nickel(II center is coordinated by two P atoms of the chelating PNP ligand, Ph2PN(iPrPPh2, and two bromide ions in a distorted square-planar geometry.

  16. Stabilization of N,N′-bis(3-methylphenyl)-N,N′-bis(phenyl)benzidine thin film morphology with UV light

    Energy Technology Data Exchange (ETDEWEB)

    Tomović, A.Ž.; Markešević, N. [Institute of Physics, University of Belgrade, Pregrevica 118, 11000 Belgrade (Serbia); Scarpellini, M.; Bovio, S. [Interdisciplinary Centre for Nanostructured Materials and Interfaces (CIMAINA), Università di Milano, Via Celoria 16, 20133 Milan (Italy); Lucenti, E. [Interdisciplinary Centre for Nanostructured Materials and Interfaces (CIMAINA), Università di Milano, Via Celoria 16, 20133 Milan (Italy); Institute of Molecular Science and Technology of CNR, via Golgi 19, 20133 Milan (Italy); Milani, P. [Interdisciplinary Centre for Nanostructured Materials and Interfaces (CIMAINA), Università di Milano, Via Celoria 16, 20133 Milan (Italy); Zikic, R. [Institute of Physics, University of Belgrade, Pregrevica 118, 11000 Belgrade (Serbia); Jovanović, V.P., E-mail: vladimir.jovanovic@ipb.ac.rs [Institute of Physics, University of Belgrade, Pregrevica 118, 11000 Belgrade (Serbia); Srdanov, V.I. [Interdisciplinary Centre for Nanostructured Materials and Interfaces (CIMAINA), Università di Milano, Via Celoria 16, 20133 Milan (Italy)

    2014-07-01

    Owing to their low glass transition temperature, T{sub g}, amorphous thin films of N,N′-bis(3-methylphenyl)-N,N′-bis(phenyl)benzidine (TPD) undergo morphological changes even at room temperature. It has been noticed previously that exposure to UV light can increase apparent T{sub g} of TPD films and thus stabilize their morphology. However, the reason behind increase in structural stability was not examined at the time. Here we present evidence that TPD molecules undergo photo-oxidation in air when exposed to λ ≈ 350 nm radiation and that less than 5% of the photo-oxidized species are needed to prevent dewetting of thin TPD films. We propose that photo-oxidized TPD species bind strongly to both ordinary TPD molecules and to terminal hydroxyl groups at the substrate surface, which decreases mobility of TPD molecules and makes thin TPD film less prone to morphology changes. - Highlights: • We made variable thickness TPD films and exposed them to UV light under ambient conditions. • Mass spectroscopy and proton NMR measurements of irradiated and pristine TPD films • TPD molecules undergo oxidation process under UV light irradiation. • Dipole–dipole interactions may be responsible for stabilization of morphological changes.

  17. Automated genotyping of dinucleotide repeat markers

    Energy Technology Data Exchange (ETDEWEB)

    Perlin, M.W.; Hoffman, E.P. [Carnegie Mellon Univ., Pittsburgh, PA (United States)]|[Univ. of Pittsburgh, PA (United States)

    1994-09-01

    The dinucleotide repeats (i.e., microsatellites) such as CA-repeats are a highly polymorphic, highly abundant class of PCR-amplifiable markers that have greatly streamlined genetic mapping experimentation. It is expected that over 30,000 such markers (including tri- and tetranucleotide repeats) will be characterized for routine use in the next few years. Since only size determination, and not sequencing, is required to determine alleles, in principle, dinucleotide repeat genotyping is easily performed on electrophoretic gels, and can be automated using DNA sequencers. Unfortunately, PCR stuttering with these markers generates not one band for each allele, but a pattern of bands. Since closely spaced alleles must be disambiguated by human scoring, this poses a key obstacle to full automation. We have developed methods that overcome this obstacle. Our model is that the observed data is generated by arithmetic superposition (i.e., convolution) of multiple allele patterns. By quantitatively measuring the size of each component band, and exploiting the unique stutter pattern associated with each marker, closely spaced alleles can be deconvolved; this unambiguously reconstructs the {open_quotes}true{close_quotes} allele bands, with stutter artifact removed. We used this approach in a system for automated diagnosis of (X-linked) Duchenne muscular dystrophy; four multiplexed CA-repeats within the dystrophin gene were assayed on a DNA sequencer. Our method accurately detected small variations in gel migration that shifted the allele size estimate. In 167 nonmutated alleles, 89% (149/167) showed no size variation, 9% (15/167) showed 1 bp variation, and 2% (3/167) showed 2 bp variation. We are currently developing a library of dinucleotide repeat patterns; together with our deconvolution methods, this library will enable fully automated genotyping of dinucleotide repeats from sizing data.

  18. Quality control during repeated fryings

    Directory of Open Access Journals (Sweden)

    Cuesta, C.

    1998-08-01

    Full Text Available Most of the debate ¡s about how the slow or frequent turnover of fresh fat affects the deterioration, of fat used in frying. Then, the modification of different oils used in repeated fryings of potatoes without or with turnover of fresh oil, under similar frying conditions, was evaluated by two criteria: by measuring the total polar component isolated by column chromatography and by the evaluation of the specific compounds related to thermoxidative and hydrolytic alteration by High Performance Size Exclusion Chromatography (HPSEC. The results indicate that with frequent turnover of fresh oil, the critical level of 25% of polar material is rarely reached, and there are fewer problems with fat deterioration because the frying tended to increase the level of polar material and thermoxidative compounds (polymers and dimers of triglycerides and oxidized triglycerides in the fryer oil during the first fryings, followed by minor changes and a tendency to reach a near-steady state in successive fryings. However, in repeated frying of potatoes using a null turnover the alteration rate was higher being linear the relationship found between polar material or the different thermoxidative compounds and the number of fryings. On the other hand chemical reactions produced during deep-fat frying can be minimized by using proper oils. In addition the increased level of consumers awareness toward fat composition and its impact on human health could had an impact on the selection of fats for snacks and for industry. In this way monoenic fats are the most adequate from a nutritional point of view and for its oxidative stability during frying.

  19. Expansion of protein domain repeats.

    Directory of Open Access Journals (Sweden)

    Asa K Björklund

    2006-08-01

    Full Text Available Many proteins, especially in eukaryotes, contain tandem repeats of several domains from the same family. These repeats have a variety of binding properties and are involved in protein-protein interactions as well as binding to other ligands such as DNA and RNA. The rapid expansion of protein domain repeats is assumed to have evolved through internal tandem duplications. However, the exact mechanisms behind these tandem duplications are not well-understood. Here, we have studied the evolution, function, protein structure, gene structure, and phylogenetic distribution of domain repeats. For this purpose we have assigned Pfam-A domain families to 24 proteomes with more sensitive domain assignments in the repeat regions. These assignments confirmed previous findings that eukaryotes, and in particular vertebrates, contain a much higher fraction of proteins with repeats compared with prokaryotes. The internal sequence similarity in each protein revealed that the domain repeats are often expanded through duplications of several domains at a time, while the duplication of one domain is less common. Many of the repeats appear to have been duplicated in the middle of the repeat region. This is in strong contrast to the evolution of other proteins that mainly works through additions of single domains at either terminus. Further, we found that some domain families show distinct duplication patterns, e.g., nebulin domains have mainly been expanded with a unit of seven domains at a time, while duplications of other domain families involve varying numbers of domains. Finally, no common mechanism for the expansion of all repeats could be detected. We found that the duplication patterns show no dependence on the size of the domains. Further, repeat expansion in some families can possibly be explained by shuffling of exons. However, exon shuffling could not have created all repeats.

  20. DWI Repeaters and Non-Repeaters: A Comparison.

    Science.gov (United States)

    Weeber, Stan

    1981-01-01

    Discussed how driving-while-intoxicated (DWI) repeaters differed signigicantly from nonrepeaters on 4 of 23 variables tested. Repeaters were more likely to have zero or two dependent children, attend church frequently, drink occasionally and have one or more arrests for public intoxication. (Author)

  1. To Repeat or Not to Repeat a Course

    Science.gov (United States)

    Armstrong, Michael J.; Biktimirov, Ernest N.

    2013-01-01

    The difficult transition from high school to university means that many students need to repeat (retake) 1 or more of their university courses. The authors examine the performance of students repeating first-year core courses in an undergraduate business program. They used data from university records for 116 students who took a total of 232…

  2. RuBisCO in Non-Photosynthetic Alga Euglena longa: Divergent Features, Transcriptomic Analysis and Regulation of Complex Formation.

    Directory of Open Access Journals (Sweden)

    Kristína Záhonová

    Full Text Available Euglena longa, a close relative of the photosynthetic model alga Euglena gracilis, possesses an enigmatic non-photosynthetic plastid. Its genome has retained a gene for the large subunit of the enzyme RuBisCO (rbcL. Here we provide new data illuminating the putative role of RuBisCO in E. longa. We demonstrated that the E. longa RBCL protein sequence is extremely divergent compared to its homologs from the photosynthetic relatives, suggesting a possible functional shift upon the loss of photosynthesis. Similarly to E. gracilis, E. longa harbors a nuclear gene encoding the small subunit of RuBisCO (RBCS as a precursor polyprotein comprising multiple RBCS repeats, but one of them is highly divergent. Both RBCL and the RBCS proteins are synthesized in E. longa, but their abundance is very low compared to E. gracilis. No RBCS monomers could be detected in E. longa, suggesting that processing of the precursor polyprotein is inefficient in this species. The abundance of RBCS is regulated post-transcriptionally. Indeed, blocking the cytoplasmic translation by cycloheximide has no immediate effect on the RBCS stability in photosynthetically grown E. gracilis, but in E. longa, the protein is rapidly degraded. Altogether, our results revealed signatures of evolutionary degradation (becoming defunct of RuBisCO in E. longa and suggest that its biological role in this species may be rather unorthodox, if any.

  3. RuBisCO in Non-Photosynthetic Alga Euglena longa: Divergent Features, Transcriptomic Analysis and Regulation of Complex Formation

    Science.gov (United States)

    Záhonová, Kristína; Füssy, Zoltán; Oborník, Miroslav; Eliáš, Marek

    2016-01-01

    Euglena longa, a close relative of the photosynthetic model alga Euglena gracilis, possesses an enigmatic non-photosynthetic plastid. Its genome has retained a gene for the large subunit of the enzyme RuBisCO (rbcL). Here we provide new data illuminating the putative role of RuBisCO in E. longa. We demonstrated that the E. longa RBCL protein sequence is extremely divergent compared to its homologs from the photosynthetic relatives, suggesting a possible functional shift upon the loss of photosynthesis. Similarly to E. gracilis, E. longa harbors a nuclear gene encoding the small subunit of RuBisCO (RBCS) as a precursor polyprotein comprising multiple RBCS repeats, but one of them is highly divergent. Both RBCL and the RBCS proteins are synthesized in E. longa, but their abundance is very low compared to E. gracilis. No RBCS monomers could be detected in E. longa, suggesting that processing of the precursor polyprotein is inefficient in this species. The abundance of RBCS is regulated post-transcriptionally. Indeed, blocking the cytoplasmic translation by cycloheximide has no immediate effect on the RBCS stability in photosynthetically grown E. gracilis, but in E. longa, the protein is rapidly degraded. Altogether, our results revealed signatures of evolutionary degradation (becoming defunct) of RuBisCO in E. longa and suggest that its biological role in this species may be rather unorthodox, if any. PMID:27391690

  4. Perioperative cerebral ischaemia in cardiac surgery and BIS.

    Science.gov (United States)

    Villacorta, J; Kerbaul, F; Collart, F; Guidon, C; Bonnet, M; Guillen, J C; Gouin, F

    2005-08-01

    A 46-year-old woman was monitored by bispectral index monitoring (BIS) during redo aortic and mitral valve replacement. On release of the aortic cross clamp there was a sudden, severe, unexplained, and sustained fall in the BIS value. Postoperatively, a CT scan was consistent with multiple ischaemic lesions. The lesions were presumed to be due to air embolism. This case suggests that a sudden unexplained and persistent fall in BIS may indicate cerebral ischaemia.

  5. Comparisons Between Tridentate Bis(benzazoles-pyridine and Bis(benzazolestriazine Ligands: a Theoretical Study

    Directory of Open Access Journals (Sweden)

    Mihaiela Andoni

    2015-12-01

    Full Text Available Twelve bis(benzazole structures with potential ligand character were investigated by means of computational chemistry. Global and local reactivity descriptors within DFT (Density Functional Theory theory (Fukui functions, chemical potential, hardness, electrophilicity index have been computed at B3LYP/6-31G(d,p level of theory. NICS(0 (Nucleus Independent Chemical Shift index computations were employed for the evaluation of the local aromatic character of each heterocyclic moiety. Best results have been reported for the bis(benzimidazole derivatives. Copper and zinc complexes of the investigated tridentate ligands have been proposed.

  6. Nifty Nines and Repeating Decimals

    Science.gov (United States)

    Brown, Scott A.

    2016-01-01

    The traditional technique for converting repeating decimals to common fractions can be found in nearly every algebra textbook that has been published, as well as in many precalculus texts. However, students generally encounter repeating decimal numerals earlier than high school when they study rational numbers in prealgebra classes. Therefore, how…

  7. Nifty Nines and Repeating Decimals

    Science.gov (United States)

    Brown, Scott A.

    2016-01-01

    The traditional technique for converting repeating decimals to common fractions can be found in nearly every algebra textbook that has been published, as well as in many precalculus texts. However, students generally encounter repeating decimal numerals earlier than high school when they study rational numbers in prealgebra classes. Therefore, how…

  8. Seasonal variation in objectively measured physical activity, sedentary time, cardio-respiratory fitness and sleep duration among 8–11 year-old Danish children: a repeated-measures study

    DEFF Research Database (Denmark)

    Hjorth, Mads F.; Chaput, Jean-Philippe; Michaelsen, Kim

    2013-01-01

    and total physical activity, moderate-to-vigorous physical activity and sleep duration (boys only) were lower during weekends at all seasons (P ≤ 0.01). Intraclass correlation coefficients between seasons ranged from 0.47-0.74, leaving 45-78% to seasonal variation. CONCLUSIONS: Overall, sedentary time...... was, therefore, to examine between-season and within-week variation in physical activity, sedentary behaviour, cardio-respiratory fitness and sleep duration among 8–11 year-old children. METHODS: A total of 1021 children from nine Danish schools were invited to participate and 834 accepted. Due...... was higher and physical activity lower during winter and during weekends. The most accurate and unbiased estimates of physical activity came from autumn; however, the considerable intra-individual variation suggests that a single measurement may not adequately characterise children’s habitual sleep...

  9. Seasonal variation in objectively measured physical activity, sedentary time, cardio-respiratory fitness and sleep duration among 8–11 year-old Danish children: a repeated-measures study

    DEFF Research Database (Denmark)

    Hjorth, Mads F.; Chaput, Jean-Philippe; Michaelsen, Kim

    2013-01-01

    was, therefore, to examine between-season and within-week variation in physical activity, sedentary behaviour, cardio-respiratory fitness and sleep duration among 8–11 year-old children. METHODS: A total of 1021 children from nine Danish schools were invited to participate and 834 accepted. Due...... to missing data, 730 children were included in the current analytical sample. An accelerometer was worn for 7 days and 8 nights during autumn, winter and spring, from which physical activity, sedentary time and sleep duration were measured. Cardio-respiratory fitness was assessed using a 10-min intermittent...... running test. RESULTS: The children had 5% more sedentary time, 23% less time in moderate-to-vigorous physical activity and 2% longer sleep duration during winter compared to spring and cardio-respiratory fitness was 4% higher during spring compared to autumn (P Sedentary time was higher...

  10. Intramolecular Electron Transfer in Bis(tetraalkyl Hydrazine) and Bis(hydrazyl) Radical Cations.

    Science.gov (United States)

    Chang, Hao

    A series of multicyclic bis(hydrazine) and bis(diazenium) compounds connected by relatively rigid hydrocarbon frameworks were prepared for the study of intramolecular electron transfer. The thermodynamics of electron removal of these compounds was investigated by cyclic voltammetry. The difference between the first and second oxidation potentials for the 4 sigma-bonded species was found to be larger for the bis(hydrazyl) radical systems than for the bis(hydrazines) by ca. 0.2 V (4.6 kcal/mol). This indicates a greater degree of interaction between the two nitrogen moieties for the hydrazyl systems, which is consistent with a greater degree of electronic coupling (H _{rm AB}) in these systems. The ESR spectra of the 4 sigma -bonded bis(hydrazine) radical cations indicate localized radical cations, which corresponds to slow intramolecular electron transfer on the ESR timescale. Conversely, the ESR spectra of the corresponding bis(hydrazyl) radical cation systems show nitrogen hyperfine splittings of a(4N) of ca. 4.5 G. This indicates that intramolecular electron transfer between the two nitrogen moieties is fast on the ESR timescale; the rate of exchange, k_ {rm ex} was estimated to be well above 1.9 times 10^8 s^{-1}. The contrast in exchange rates is consistent with the large geometry change upon oxidation which is characteristic of hydrazines. The hydrazyls undergo a smaller geometry change upon oxidation, and thus are expected to exhibit smaller inner-sphere reorganization energies. The optical spectra of these radical species was investigated in hopes of observing absorption bands corresponding to intramolecular electron transfer, as predicted by Hush theory. A broad absorption band was observed in the near IR region for the saturated bis(hydrazyl) radical cation system at 1060 nm (9420 cm^{-1} ) in acetonitrile at room temperature, and was accompanied by a narrower band at 1430 nm (6993 cm^ {-1}). The width of this band was estimated to be 545 nm (6496 cm^{-1

  11. 重複觀測量數之分析:多群體多變項線性成長模式的估計Data Analysis of Repeated Measures: Estimating a Multi-Group Multivariate Linear Growth Model

    Directory of Open Access Journals (Sweden)

    溫福星 Fur-Hsing Wen

    2012-03-01

    Full Text Available 本研究利用「台灣教育長期追蹤資料庫」的一般分析能力與數學分析能力的四波調查結果,配合男、女學生樣本進行多群體多條追蹤資料的線性成長模式估計。在考慮重複觀測資料誤差項在不同時點的變異數非同質與不同時點間的共變數非獨立情況下,以及男、女學生的不同成長軌跡,將誤差項結構設為無限制結構,利用虛擬變項交互項法與虛擬變項多樣本法同時估計不同性別、不同能力的線性成長軌跡變化。由於全部追蹤資料樣本存在遺失值的情形,本研究以階層線性模式(hierarchical linear modeling, HLM)軟體對完整資料2,806位學生進行分析,其估計結果發現,在完整資料的兩條成長軌跡模式中,男、女學生誤差項共變異數矩陣結構相同,但線性成長軌跡不恆等。除此之外,本文並對競爭模式比較的結果在文章最後進行討論並提出相關的建議。 This paper demonstrates the data analysis of the repeated measures from the Taiwan Education Panel Survey (TEPS. Based on the four data waves on the TEPS, we consider two abilities (general and mathematic and two population groups (male and female students to construct a multi-group multivariate linear growth model. Because the two-group multivariate repeated measures belong to the different populations and the different research variables, the residual terms of linear growth models may imply heterogeneity of the error covariance structure. We treat the error covariance structure as an unrestricted structure to compare the various types of models. The results from the HLM on the complete data (2,806 students reveal that the male and female students in this study have the same error covariance structure but have distinct linear growth trajectories. In addition, comparisons of the competitive models and related suggestions are discussed in the results and conclusion

  12. 40 CFR 721.5760 - Phenol, 4,4′-[methylene-bis (oxy-2,1-ethanediylthio)]bis-.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Phenol, 4,4â²- bis-. 721.5760 Section... Substances § 721.5760 Phenol, 4,4′- bis-. (a) Chemical substances and significant new uses subject to reporting. (1) The chemical substance phenol, 4,4′- bis- (PMN P-87-1760) is subject to reporting under...

  13. Synthesis and Thermal Rearrangement of Tetramethyldisilane-bridged Bis(cyclopentadienyl) Diiron Complexes with Bis(phosphine)Substitution

    Institute of Scientific and Technical Information of China (English)

    孙秀丽; 王佰全; 等

    2003-01-01

    Photolysis of [Me2SiSiMe2)[C5H4Fe(CO2)]2with a series of bis(phosphine)ligands Ph2P(CH2)n PPh2(n=1-4) leads to the formation of the corresponding diiron complexes with intramolecular and intermolecular bis(phosphine) substitution.When these complexes were heated in refluxing xylene.only in the complexes with intermolecular bis(phosphine )substitution the thermal rearrangement reaction occurred.

  14. 21 CFR 73.3100 - 1,4-Bis[(2-hydroxyethyl)amino]-9,10-anthracenedione bis(2-propenoic)ester copolymers.

    Science.gov (United States)

    2010-04-01

    ...)ester copolymers. 73.3100 Section 73.3100 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... § 73.3100 1,4-Bis -9,10-anthracenedione bis(2-propenoic)ester copolymers. (a) Identity. The color additives are 1,4-bis -9,10-anthracenedione bis(2-propenoic)ester (CAS Reg. No. 109561-07-1)...

  15. Repeated sprint training in normobaric hypoxia.

    Science.gov (United States)

    Galvin, Harvey M; Cooke, Karl; Sumners, David P; Mileva, Katya N; Bowtell, Joanna L

    2013-12-01

    Repeated sprint ability (RSA) is a critical success factor for intermittent sport performance. Repeated sprint training has been shown to improve RSA, we hypothesised that hypoxia would augment these training adaptations. Thirty male well-trained academy rugby union and rugby league players (18.4 ± 1.5 years, 1.83 ± 0.07 m, 88.1 ± 8.9 kg) participated in this single-blind repeated sprint training study. Participants completed 12 sessions of repeated sprint training (10 × 6 s, 30 s recovery) over 4 weeks in either hypoxia (13% FiO₂) or normoxia (21% FiO₂). Pretraining and post-training, participants completed sports specific endurance and sprint field tests and a 10 × 6 s RSA test on a non-motorised treadmill while measuring speed, heart rate, capillary blood lactate, muscle and cerebral deoxygenation and respiratory measures. Yo-Yo Intermittent Recovery Level 1 test performance improved after RS training in both groups, but gains were significantly greater in the hypoxic (33 ± 12%) than the normoxic group (14 ± 10%, prepeated aerobic high intensity workout than an equivalent normoxic training. Performance gains are evident in the short term (4 weeks), a period similar to a preseason training block.

  16. A repeated-measures analysis of the effects of soft tissues on wrist range of motion in the extant phylogenetic bracket of dinosaurs: Implications for the functional origins of an automatic wrist folding mechanism in Crocodilia.

    Science.gov (United States)

    Hutson, Joel David; Hutson, Kelda Nadine

    2014-07-01

    A recent study hypothesized that avian-like wrist folding in quadrupedal dinosaurs could have aided their distinctive style of locomotion with semi-pronated and therefore medially facing palms. However, soft tissues that automatically guide avian wrist folding rarely fossilize, and automatic wrist folding of unknown function in extant crocodilians has not been used to test this hypothesis. Therefore, an investigation of the relative contributions of soft tissues to wrist range of motion (ROM) in the extant phylogenetic bracket of dinosaurs, and the quadrupedal function of crocodilian wrist folding, could inform these questions. Here, we repeatedly measured wrist ROM in degrees through fully fleshed, skinned, minus muscles/tendons, minus ligaments, and skeletonized stages in the American alligator Alligator mississippiensis and the ostrich Struthio camelus. The effects of dissection treatment and observer were statistically significant for alligator wrist folding and ostrich wrist flexion, but not ostrich wrist folding. Final skeletonized wrist folding ROM was higher than (ostrich) or equivalent to (alligator) initial fully fleshed ROM, while final ROM was lower than initial ROM for ostrich wrist flexion. These findings suggest that, unlike the hinge/ball and socket-type elbow and shoulder joints in these archosaurs, ROM within gliding/planar diarthrotic joints is more restricted to the extent of articular surfaces. The alligator data indicate that the crocodilian wrist mechanism functions to automatically lock their semi-pronated palms into a rigid column, which supports the hypothesis that this palmar orientation necessitated soft tissue stiffening mechanisms in certain dinosaurs, although ROM-restricted articulations argue against the presence of an extensive automatic mechanism. Anat Rec, 297:1228-1249, 2014. © 2014 Wiley Periodicals, Inc.

  17. Functional materials from self-assembled bis-urea macrocycles.

    Science.gov (United States)

    Shimizu, Linda S; Salpage, Sahan R; Korous, Arthur A

    2014-07-15

    CONSPECTUS: This Account highlights the work from our laboratories on bis-urea macrocycles constructed from two C-shaped spacers and two urea groups. These simple molecular units assembled with high fidelity into columnar structures guided by the three-centered urea hydrogen bonding motif and aryl stacking interactions. Individual columns are aligned and closely packed together to afford functional and homogeneous microporous crystals. This approach allows for precise and rational control over the dimensions of the columnar structure simply by changing the small molecular unit. When the macrocyclic unit lacks a cavity, columnar assembly gives strong pillars. Strong pillars with external functional groups such as basic lone pairs can expand like clays to accept guests between the pillars. Macrocycles that contain sizable interior cavities assemble into porous molecular crystals with aligned, well-defined columnar pores that are accessible to gases and guests. Herein, we examine the optimal design of the macrocyclic unit that leads to columnar assembly in high fidelity and probe the feasibility of incorporating a second functional group within the macrocycles. The porous molecular crystals prepared through the self-assembly of bis-urea macrocycles display surface areas similar to zeolites but lower than MOFs. Their simple one-dimensional channels are well-suited for studying binding, investigating transport, diffusion and exchange, and monitoring the effects of encapsulation on reaction mechanism and product distribution. Guests that complement the size, shape, and polarity of the channels can be absorbed into these porous crystals with repeatable stoichiometry to form solid host-guest complexes. Heating or extraction with an organic solvent enables desorption or removal of the guest and subsequent recovery of the solid host. Further, these porous crystals can be used as containers for the selective [2 + 2] cycloadditions of small enones such as 2-cyclohexenone or 3

  18. Conductivity of oriented bis-azo polymer films

    DEFF Research Database (Denmark)

    Apitz, D.; Bertram, R.P.; Benter, N.;

    2006-01-01

    The conductivity properties of electro-optic photoaddressable, dense bis-ozo chromophore polymer films are investigated by using samples corona poled at various temperatures. A dielectric spectrometer is applied to measure the frequency dependence of the conductivity at different temperatures...... before and after heating the material to above the glass transition temperature. The results show that the orientation of the chromophores changes the charge-carrier mobility. Ionic conductivity dominates in a more disordered configuration of the material, while the competing process of hole hopping...... takes over as a transition to a liquid-crystalline phase occurs when the material is heated to much higher than the gloss transition temperature. Such micro-crystallization strongly enhances the conductivity....

  19. Safety of Repeated Yttrium-90 Radioembolization

    Energy Technology Data Exchange (ETDEWEB)

    Lam, Marnix G. E. H.; Louie, John D. [Stanford University School of Medicine, Division of Interventional Radiology (United States); Iagaru, Andrei H.; Goris, Michael L. [Stanford University School of Medicine, Division of Nuclear Medicine (United States); Sze, Daniel Y., E-mail: dansze@stanford.edu [Stanford University School of Medicine, Division of Interventional Radiology (United States)

    2013-10-15

    Purpose: Repeated radioembolization (RE) treatments carry theoretically higher risk of radiation-induced hepatic injury because of the liver's cumulative memory of previous exposure. We performed a retrospective safety analysis on patients who underwent repeated RE. Methods: From 2004 to 2011, a total of 247 patients were treated by RE. Eight patients (5 men, 3 women, age range 51-71 years) underwent repeated treatment of a targeted territory, all with resin microspheres (SIR-Spheres; Sirtex, Lane Cove, Australia). Adverse events were graded during a standardized follow-up. In addition, the correlation between the occurrence of RE-induced liver disease (REILD) and multiple variables was investigated in univariate and multivariate analyses in all 247 patients who received RE. Results: Two patients died shortly after the second treatment (at 84 and 107 days) with signs and symptoms of REILD. Both patients underwent whole liver treatment twice (cumulative doses 3.08 and 2.66 GBq). The other 6 patients demonstrated only minor toxicities after receiving cumulative doses ranging from 2.41 to 3.88 GBq. All patients experienced objective tumor responses. In the whole population, multifactorial analysis identified three risk factors associated with REILD: repeated RE (p = 0.036), baseline serum total bilirubin (p = 0.048), and baseline serum aspartate aminotransferase (p = 0.043). Repeated RE proved to be the only independent risk factor for REILD in multivariate analysis (odds ratio 9.6; p = 0.002). Additionally, the administered activity per target volume (in GBq/L) was found to be an independent risk factor for REILD, but only in whole liver treatments (p = 0.033). Conclusion: The risk of REILD appears to be elevated for repeated RE. Objective tumor responses were observed, but establishment of safety limits will require improvement in dosimetric measurement and prediction.

  20. Poly[bis[μ-1,4-bis(imidazol-1-ylmethylbenzene]dichloridocadmium(II

    Directory of Open Access Journals (Sweden)

    Xinliang Hu

    2008-07-01

    Full Text Available The title compound, [CdCl2(C14H14N42]n, has a slightly distorted octahedral coordination geometry, formed by four N atoms from 1,4-bis(imidazol-1-ylmethylbenzene ligands and two Cl atoms, giving a two-dimensional network. The Cd atom lies on a centre of inversion.

  1. Bis[N,N-bis(2-hydroxyethyldithiocarbamato-κ2S,S′]copper(II

    Directory of Open Access Journals (Sweden)

    Jun Fan

    2009-12-01

    Full Text Available In the title compound, [Cu(C5H10NO2S22], the CuII cation is chelated by two bis(2-hydroxyethyldithiocarbamate anions with a distorted square-planar coordination geometry. Intermolecular O—H...O hydrogen bonding is observed between the terminal hydroxy groups in the crystal structure.

  2. Study of bis(bibenzyls) in bryophytes using electron ionization time-of-flight and electrospray ionization triple-quadrupole mass spectrometry.

    Science.gov (United States)

    Guo, Huaifang; Xing, Jie; Xie, Chunfeng; Qu, Jianbo; Gao, Yanhui; Lou, Hongxiang

    2007-01-01

    A detailed analysis of mass spectra generated from bis(bibenzyl) compounds in bryophytes under electron ionization time-of-flight (EI-TOF) and electrospray ionization triple-quadrupole (ESI-TQ) mass spectrometry conditions is reported. Proposed structures of the fragment ions were obtained by tracking the functional groups of 15 bis(bibenzyls), the structures of which are similar except for some alkoxyl substituents and linkage sites of biphenyl ether bonds. The elucidation was aided by the use of accurate mass measurements. Attempts have been made to provide rational pathways for the formation of these fragment ions, and a generalized fragmentation mechanism is proposed. The bis(bibenzyls) mentioned in this study include three types according to their structure characteristics, i.e. one biphenyl ether bond (A-type), two biphenyl ether bonds (B-type), one biphenyl ether and one biphenyl bond (C-type). The three types display different EI-MS and ESI-MS/MS product profiles, by which the bis(bibenzyl) type and the number of alkoxyl substituents can be identified. Isomers of bis(bibenzyls) can be differentiated to some extent, while the linkage sites of biphenyl ether bonds are difficult to identify. The structure-fragmentation relationships will facilitate the characterization of other bis(bibenzyls) and this will be of value for the high-throughput screening of novel bis(bibenzyls) in bryophytes.

  3. Effect of Repeated Simulations by Standardized Patients on Intercase Reliability.

    Science.gov (United States)

    Colliver, Jerry A.; And Others

    1991-01-01

    A study using five Southern Illinois University senior medical school classes (n=350 students) investigated whether having a standardized patient simulate a case repeatedly in postclerkship medical student evaluation affects the measure's reliability. Results suggest that repeated simulation had little or no effect on intercase reliability of…

  4. Repeated-sprint and effort ability in rugby league players.

    Science.gov (United States)

    Johnston, Rich D; Gabbett, Tim J

    2011-10-01

    The aim of this study was to (a) investigate the influence of tackling on repeated-sprint performance; (b) determine whether repeated-sprint ability (RSA) and repeated-effort ability (REA) are 2 distinct qualities; and (c) assess the test-retest reliability of repeated-sprint and repeated-effort tests in rugby league. Twelve rugby league players performed a repeated-sprint (12 × 20-m sprints performed on a 20-second cycle) and a repeated-effort (12 × 20-m sprints with intermittent tackling, performed on a 20-second cycle) test 7 days apart. The test-retest reliability of these tests was also established. Heart rate and rating of perceived exertion were recorded throughout the tests. There was a significantly greater (p ≤ 0.05) and large effect size (ES) differences for total sprint time (ES = 1.19), average heart rate (ES = 1.64), peak heart rate (ES = 1.35), and perceived exertion (ES = 3.39) for the repeated-effort test compared with the repeated-sprint test. A large difference (ES = 1.02, p = 0.06) was detected for percentage decrement between the 2 tests. No significant relationship was found between the repeated-sprint and repeated-effort tests for any of the dependent variables. Both tests proved reliable, with total sprint time being the most reliable method of assessing performance. This study demonstrates that the addition of tackling significantly increases the physiological response to repeated-sprint exercise and reduces repeated-sprint performance in rugby league players. Furthermore, RSA and REA appear to be 2 distinct qualities that can be reliably assessed with total time being the most reliable measure of performance.

  5. Psychometric Properties of the BIS/BAS Scales and the SPSRQ in Flemish Adolescents

    Directory of Open Access Journals (Sweden)

    Laura Vandeweghe

    2016-12-01

    Full Text Available Objective: Gray’s Reinforcement Sensitivity Theory (RST is a frequently used model of personality that is relevant to the period of adolescence. However, the psychometric properties of the most frequently used questionnaires to measure the RST-constructs, namely the Behavioural Inhibition System and Behavioural Activation System Scales (BIS/BAS Scales and the Sensitivity to Punishment and Sensitivity to Reward Questionnaire (SPSRQ, are rarely examined in samples of adolescents. Therefore, the goal of the present study was to examine the two-factor structure, reliability and convergent validity of the BIS/BAS Scales and SPSRQ in a Flemish adolescent community sample.  Method: A sample of 579 adolescents (39.5% boys; 14–19 years was recruited. The proposed two-factor structure was assessed using Exploratory Structural Equation Modeling. Reliability was evaluated using internal consistency and construct validity was examined with the correlations between the two questionnaires and with the Temperament and Character Inventory–short form (TCI-SF.  Results: After the removal of problematic items, and the addition of correlated errors, all indices indicated a good fit for the two-factor structure of the modified BIS/BAS Scales. For the modified SPSRQ, three fit indices indicated a good model fit, while a fourth fit index was slightly below the cut-off score of an adequate model fit. Internal consistency of both questionnaires was sufficient. In general, the associations with scales of the TCI-SF were as expected, with positive correlations between BIS-related scales, and between BAS-related scales of all three instruments.  Discussion: In Flemish adolescents, the use of a two-factor model to analyze data gathered with the modified BIS/BAS Scales or modified SPSRQ seems appropriate.

  6. Bis-perfluoroalkylation of aromatic compounds with sodium perfluoroalkanesulfinates

    Institute of Scientific and Technical Information of China (English)

    LIU, Jin-Tao(刘金涛); LU, He-Jun(吕贺军)

    2000-01-01

    Bis-perfluoroalkylation of aromatic compounds such as dimethoxybenzenes (2,4,6), anisole (8), pyridine (10) and quinoline (13) was accomplished by reaction with excess sodium perfluoroalkanesulfinates, RFSO2Na (1), in the presence of Mn(OAc)3·2H2O under mild conditions. The reaction provides a facile method for the synthesis of bis-perfluoroalkylated aromatic compounds.

  7. Synthesis, spectral and structural properties of bis-imidazoline selones

    Indian Academy of Sciences (India)

    Arruri Sathyanarayana; Katam Srinivas; Anindita Mandal; Saswati Gharami; Ganesan Prabusankar

    2014-09-01

    New biphenyl derivatives of bis-imidazoline selones were synthesized in good yield and characterized by multinuclear (1D and 2D) NMR and UV-vis studies. The solid state structures of bis-imidazoline selones were further confirmed by single crystal X ray diffraction technique.

  8. Accelerated optical holographic recording using bis-DNO

    DEFF Research Database (Denmark)

    Rasmussen, Palle H.; Ramanujam, P.S.; Hvilsted, Søren

    1999-01-01

    The design, synthesis and optical holographic recording properties of bis-DNO are reported. Bis-DNO is composed of two identical azobenzene oligoornithine segments (DNO) connected via a dipeptide linker. The two segments were assembled in a parallel fashion at the two amino groups of the dipeptide...

  9. Convenient Synthesis of Bis(oxazoline) Dicarboxylate Derivatives

    Institute of Scientific and Technical Information of China (English)

    Bin FU; Da Ming DU; Qing XIA

    2004-01-01

    The synthesis of bis(oxazoline) dicarboxylate derivatives was investigated.Diethyl-aminosulfur trifluoride(DAST)was used as a convenient cyclization reagent in the synthesis of bis(oxazoline)dicarboxylate derivatives,which can not be obtained by the general method using MsCl and Et3N as dehydrating cyclization reagent.

  10. Source coding model for repeated snapshot imaging

    CERN Document Server

    Li, Junhui; Yang, Dongyue; wu, Guohua; Yin, Longfei; Guo, Hong

    2016-01-01

    Imaging based on successive repeated snapshot measurement is modeled as a source coding process in information theory. The necessary number of measurement to maintain a certain level of error rate is depicted as the rate-distortion function of the source coding. Quantitative formula of the error rate versus measurement number relation is derived, based on the information capacity of imaging system. Second order fluctuation correlation imaging (SFCI) experiment with pseudo-thermal light verifies this formula, which paves the way for introducing information theory into the study of ghost imaging (GI), both conventional and computational.

  11. Repeatability Evaluation of Finger Tapping Device with Magnetic Sensors

    Science.gov (United States)

    Sano, Yuko; Kandori, Akihiko; Shima, Keisuke; Tamura, Yasuhiro; Takagi, Hiroshi; Tsuji, Toshio; Noda, Masafumi; Higashikawa, Fumiko; Yokoe, Masaru; Sakoda, Saburo

    We tested the repeatability of a finger tapping device with magnetic sensors to determine its reliability. This device, which was developed to assist in the diagnosis of movement disorders such as Parkinson's disease (PD) and strokes, measures the distance between the first and index fingers during finger tapping movements (opening and closing the fingers repeatedly). We evaluated three types of repeatability based on ICC (interclass correlation coefficient) and Welch's test (test for equal means in a oneway layout): repeatability when measured at different times, when using different devices, and when using different measurers. We calculated these three types for three finger tapping tasks on both hands for 21 characteristics calculated from finger tapping waveforms. Results demonstrated that the repeatability when using different devices is high regardless of the task or hand. The repeatability when measuring at different times and when using different measurers is high at some tasks, but not all. One of the finger tapping tasks (finger tapping movement with the largest amplitude and highest velocity), which is used in a conventional PD diagnosis method (UPDRS), does not have enough repeatability, while other tasks show high repeatability. Results also showed that five characteristics have the highest repeatability (ICC ≥ 0.5 or significance probability of Welch's test ≥ 5% in all tasks): “total moving distance,” “average of local minimum acceleration in opening motion,” “average of local minimum acceleration in closing motion,” “average of local maximum distance” and “average of local minimum velocity”. These results clearly demonstrate the strong repeatability of this device and lead to more precise diagnosis of movement disorders.

  12. A bis-calixarene from olefin metathesis

    Directory of Open Access Journals (Sweden)

    Shimelis T. Hailu

    2012-06-01

    Full Text Available A ring-closing olefin metathesis reaction of tetrakis(allyloxycalix[4]arene gave the bis calixarene, (15E,40E,60E-65,74-bis(prop-2-en-1-yloxy-13,18,38,43,58,63-hexaoxadodecacyclo[28.26.8.720,36.111,45.151,55.05,57.07,12.019,24.026,64.032,37.044,49.168,72]tetraheptaconta-1,3,5(57,7,9,11,15,19(24,20,22,26,28,30(64,32,34,36,40,44(49,45,47,51,53,55(65,60,68,70,72(74-heptacosaene, C74H68O8. It is a cage formed from two calix[4]arene units joined by butenyl groups at three of the O atoms on the narrow rim. The fourth O atom on each calixarene unit is joined with an allyl group. Each of the calix[4]arene units has a flattened cone conformation in which the allyloxy-substituted aryl group and the opposite aryl group are close together and almost parallel [dihedral angle between planes = 1.09 (11°], and the other two aryl groups are splayed outward [dihedral angle between planes = 79.53 (11°]. No guest molecule (e.g. solvent was observed within the cage. The alkene C atoms of one of the links between the calixarene moieties are disordered over two orientations with occupancies of 0.533 (9 and 0.467 (9.

  13. Repeated-sprint ability and aerobic fitness.

    Science.gov (United States)

    Thébault, Nicolas; Léger, Luc A; Passelergue, Philippe

    2011-10-01

    The purpose of this study was to reinvestigate the relationship between aerobic fitness and fatigue indices of repeated-sprint ability (RSA), with special attention to methodological normalization. Soldiers were divided into low (n = 10) and high (n = 9) fitness groups according to a preset maximal aerobic speed (MAS) of 17 km·h(-1) (∼60 ml O2·kg(-1)·min) measured with the University of Montreal Track Test (UMTT). Subjects' assessment included the RSA test (3 sets of 5 40-m sprints with 1-minute rest between sprints and 1.5 minutes between sets), a 40-m sprint (criterion test used in the computation of fatigue indices for the RSA test), strength and power measurement of the lower limbs, and the 20-m shuttle run test (20-m SRT) and the UMTT, which are measures of maximal aerobic power. The highest correlation with the RSA fatigue indices was obtained with the 20-m SRT (r = 0.90, p = 0.0001, n = 19), a test with 180° direction changes and accelerations and decelerations. The lower correlation (r = 0.66, p repeated sprints and achieved better recovery between series. A MAS of at least 17 km·h(-1) favors constant and high speed level during repeated sprints. From a practical point of view, a high aerobic fitness is a precious asset in counteracting fatigue in sports with numerous sprint repetitions.

  14. Who Repeats Algebra, and How Does Initial Performance Relate to Improvement When the Course Is Repeated?

    Science.gov (United States)

    Fong, Anthony; Jaquet, Karina; Finkelstein, Neal

    2016-01-01

    The information provided in this report shows how students perform when they repeat algebra I and how the level of improvement varies depending on initial course performance and the academic measure (course grades or CST scores). This information can help inform decisions and policies regarding whether and under what circumstances students should…

  15. Perioperative use of bispectral (BIS) monitor for a pressure ulcer patient with locked-in syndrome (LIS).

    Science.gov (United States)

    Yoo, Christine; Ayello, Elizabeth A; Robins, Bryan; Salamanca, Victor R; Bloom, Marc J; Linton, Patrick; Brem, Harold; O'Neill, Daniel K

    2014-10-01

    The bispectral (BIS) monitor uses brain electroencephalographic data to measure the depth of sedation and pharmacological response during anaesthetic procedures. In this case, the BIS monitor was used for another purpose, to demonstrate postoperatively to the nursing staff that a patient with history of locked-in syndrome (LIS), who underwent pressure ulcer debridement, had periods of wakefulness and apparent sensation, even with his eyes closed. Furthermore, as patients with LIS can feel pain, despite being unable to move, local block or general anaesthesia should be provided for sharp surgical debridement and other painful procedures. This use of the BIS has shown that as a general rule, the staff should treat the patient as though he might be awake and sensate even if he does not open his eyes or move his limbs. The goal of this study was to continuously monitor pain level and communicate these findings to the entire wound team, i.e. anaesthesiologists, surgeons and nurses.

  16. Perioperative Use of Bispectral Monitor (BIS) for a Pressure Ulcer patient with Lock-In Syndrome (LIS)

    Science.gov (United States)

    Yoo, Christine; Ayello, Elizabeth A.; Robins, Bryan; Salamanca, Victor R.; Bloom, Marc J.; Linton, Patrick; Brem, Harold; O'Neill, Daniel K.

    2013-01-01

    The bispectral (BIS) monitor uses brain electroencephalographic data to measure depth of sedation and pharmacological response during anesthetic procedures. In this case, the BIS monitor was used for another purpose, to demonstrate postoperatively to the nursing staff that a patient with history of locked-in syndrome (LIS), who underwent pressure ulcer debridement, had periods of wakefulness and apparent sensation, even with his eyes closed. Furthermore, as patients with LIS can feel pain, despite being unable to move, local block or general anesthesia should be provided for sharp surgical debridement and other painful procedures. This use of the BIS has shown that as a general rule, the staff should treat the patient as though he might be awake and sensate even if he does not open his eyes or move his limbs. Our goal was to continuously monitor pain level and communicate these findings to the entire wound team, ie anesthesiologists, surgeons, and nurses. PMID:25252146

  17. Bis(μ-bis{[4-(2-pyridylpyrimidin-2-yl]sulfanyl}methanedisilver(I bis(perchlorate

    Directory of Open Access Journals (Sweden)

    Hai-Bin Zhu

    2010-12-01

    Full Text Available In the macrocyclic centrosymmetric dinuclear complex, [Ag2(C19H14N6S22](ClO42, the AgI atom, bis{[4-(2-pyridylpyrimidin-2-yl]sulfanyl}methane (2-bppt ligand and perchlorate anion each lie on a twofold rotation axis. The 2-bppt ligand chelates two four-coordinated AgI atoms through its two bipyridine-like arms. The O atoms of the perchlorate anion are disordered each over two positions of equal occupancy. Adjacent complex molecules are linked by π–π interactions between the pyridine and pyrimidine rings [centroid–centroid distance = 3.663 (8 Å].

  18. Bis[N,N-bis(diphenylphosphanylpentylamine-κ2P,P′]platinum(II bis(hexafluoridophosphate dichloromethane disolvate

    Directory of Open Access Journals (Sweden)

    Ilana Engelbrecht

    2010-08-01

    Full Text Available The PtII atom in the title compound, [Pt(C29H31NP22](PF62·2CH2Cl2, is coordinated by four P atoms from two bis(diphenylphosphanylpentylamine ligands with an average Pt—P distance of 2.300 (1 Å. The coordination around the PtII atom shows a highly distorted square-planar geometry, as evidenced by the P—Pt—P bite angles of 70.45 (3 and 70.64 (3°. The asymmetric unit contains two hexafluoridophosphate ions, the metal complex and two dichloromethane solvent molecules. One of the chloride atoms of one of the dichloromethane molecules is disordered over two sites in a 0.515 (3:0.485 (3 ratio. C—H...F hydrogen bonds stabilize the crystal packing.

  19. Avaliação do desempenho zootécnico de genótipos de frangos de corte utilizando-se a análise de medidas repetidas Performance evaluation of broiler genotypes by repeated measures

    Directory of Open Access Journals (Sweden)

    Millor Fernandes do Rosário

    2005-12-01

    Full Text Available Objetivou-se avaliar genótipos de frangos de corte por meio do desempenho zootécnico utilizando-se medidas repetidas. Os tratamentos consistiram de quatro genótipos (A, B, C e D e dois sexos avaliados em seis idades (7, 14, 21, 28, 35 e 42 dias. As variáveis analisadas foram: consumo médio de alimento (CONS, peso vivo médio (PV e conversão alimentar (CA. O delineamento experimental foi em blocos incompletos desbalanceados, em esquema fatorial 4x2 nas parcelas experimentais, com seis medidas realizadas no decorrer do experimento. A análise estatística foi realizada por meio do procedimento MIXED do SAS®, sendo testadas cinco estruturas de variância e covariância do erro. As médias foram estimadas por quadrados mínimos e comparadas pelo teste Tukey-Kramer. Foram estimadas funções de resposta quadrática para CONS e CA e Gompertz para PV e seus respectivos coeficientes de determinação, pelo procedimento NLIN do SAS®. Detectaram-se efeitos de algumas interações triplas ou duplas para todas as variáveis. Verificaram-se diferenças significativas entre genótipos dentro de cada idade e sexo para CONS e PV e para CA entre genótipos e sexos, dentro de cada idade, apenas aos 42 e a partir dos 21 dias, respectivamente. Constatou-se que o genótipo D, apesar de apresentar maiores médias de CONS e PV, não mostrou menor CA, que foi verificada nos genótipos C e B. As funções de resposta estimadas explicaram adequadamente cada variável em função da idade, constatando-se que o CONS e PV dos machos do genótipo D foram maiores a partir dos 14 dias e dos 28 aos 42 dias, distinguindo este tratamento dos demais. A melhor CA foi verificada nos machos e no genótipo C. É possível avaliar o desempenho zootécnico de frangos de corte por medidas repetidas, sendo que os genótipos B e C apresentaram melhor desempenho zootécnico.The objetive of this study was to evaluate the performance of broiler genotypes using repeated measurements

  20. Optical and magneto-optical properties of spin coated films of novel trinuclear bis(oxamato) and bis(oxamidato) type complexes

    Energy Technology Data Exchange (ETDEWEB)

    Abdulmalic, Mohammad A. [Technische Universität Chemnitz, Fakultät für Naturwissenschaften, Institut für Chemie, Straße der Nationen 62, D-09111 Chemnitz (Germany); Fronk, Michael [Technische Universität Chemnitz, Fakultät für Naturwissenschaften, Institut für Physik, Reichenhainer Straße 70, D-09107 Chemnitz (Germany); Bräuer, Björn [Stanford Institute of Materials and Energy Science, Stanford University, Stanford, CA 94025 (United States); Zahn, Dietrich R.T. [Technische Universität Chemnitz, Fakultät für Naturwissenschaften, Institut für Physik, Reichenhainer Straße 70, D-09107 Chemnitz (Germany); Salvan, Georgeta, E-mail: salvan@physik.tu-chemnitz.de [Technische Universität Chemnitz, Fakultät für Naturwissenschaften, Institut für Physik, Reichenhainer Straße 70, D-09107 Chemnitz (Germany); Eya' ane Meva, Francois [Department of Pharmaceutical Sciences, Faculty of Medicine and Pharmaceutical Sciences, University of Douala, BP 2701 (Cameroon); and others

    2016-12-01

    This work reports the first example of the spectroscopic measurements of the Magneto-Optical Kerr Effect (MOKE) of films being composed of trinuclear transition metal complexes on a non-transparent substrate at room temperature. The thin films of the tailor-made trinuclear bis(oxamidato) type complex 5 ([Cu{sub 3}(opbo{sup n}Pr{sub 2})(tmcd){sub 2}(NO{sub 3}){sub 2}], opbo{sup n}Pr{sub 2} = o-phenylenebis(N’-{sup n}propyloxamido, tmcd=trans-(1 R,2 R)-N,N,N′,N′-tetramethyl-cyclohexanediamine) and of the bis(oxamato) type complexes 11 ([Cu{sub 2}Ni(opbaCF{sub 3})(pmdta){sub 2}(NO{sub 3}){sub 2}], opbaCF{sub 3} = 4-trifluoromethyl-o-phenylenebis(oxamato), pmdta = N,N,N,′N″,N″-pentamethyldiethylenetriamine) and 12 ([Cu{sub 3}(opba)(bppe){sub 2}(NO{sub 3}){sub 2}] (opba = o-phenylenebis(oxamato), bppe = S-N,N-bis(2-picolyl)−1-phenylethylamine) were fabricated by spin-coating and their thicknesses in the range between 0.5 µm and 2 µm was determined by spectroscopic ellipsometry. Based on the spectroscopic ellipsometry results it was also possible to determine the optical constants of the film and compare them with the absorption of the complexes in solution in order to confirm the complex integrity after the film deposition. The fabrication of high-quality films which exhibit Kerr rotation up to 0.2 mrad (11.5 mdeg) was only possible due to tailor-made synthesis, which allows circumventing intermolecular interactions of the trinuclear complexes during the film formation. - Highlights: • Tailor-made trinuclear bis(oxamidato) and bis(oxamato) type complexes were synthesized. • Thin films (between 0.5 µm and 2 µm) were fabricated by spin-coating. • The film optical constants indicate the complex integrity after the deposition. • Film quality enabled first spectroscopic MOKE measurements of multi-nuclear complexes. • Magneto-optical Kerr rotation up to 11.5 mdeg was observed at RT (in 1.7 T).

  1. Bis[N,N'-bis(diphenylmethylene)ethylenediamine-2N,N']copper(I) dichlorocuprate(I)

    NARCIS (Netherlands)

    Mirkhani, Valiollah; Harkema, Sybolt; Kia, Reza

    2004-01-01

    The 1:1 adduct of N,N'-bis(diphenylmethylene)ethylenediamine (bz2en) with copper(I) chloride, viz. [Cu(C28H24N2)2][CuCl2], has been synthesized. The structure contains cationic moieties of CuI ions (Cu on a twofold axis) coordinated to four N atoms of two bz2en molecules (in a distorted tetrahedron)

  2. Bis[N,N'-bis(diphenylmethylene)ethylenediamine-2N,N']copper(I) dichlorocuprate(I)

    NARCIS (Netherlands)

    Mirkhani, Valiollah; Harkema, Sybolt; Kia, Reza

    2004-01-01

    The 1:1 adduct of N,N'-bis(diphenylmethylene)ethylenediamine (bz2en) with copper(I) chloride, viz. [Cu(C28H24N2)2][CuCl2], has been synthesized. The structure contains cationic moieties of CuI ions (Cu on a twofold axis) coordinated to four N atoms of two bz2en molecules (in a distorted tetrahedron)

  3. Bis[1,3-bis(diphenylphosphanylpropane]copper(I tetrachloridogallate(III

    Directory of Open Access Journals (Sweden)

    Nian-Nian Wang

    2012-07-01

    Full Text Available In the title compound, [Cu(C27H26P22][GaCl4], the CuI atom in the complex cation is P,P′-chelated by two 1,3-bis(diphenylphosphanylpropane ligands in a distorted tetrahedral geometry, while the GaIII cation is coordinated by four chloride anions in a distorted tetrahedral geometry. In the crystal, weak C—H...π interactions occur between adjacent complex cations.

  4. Quantum repeaters with entangled coherent states

    CERN Document Server

    Sangouard, Nicolas; Gisin, Nicolas; Laurat, Julien; Tualle-Brouri, Rosa; Grangier, Philippe

    2009-01-01

    Entangled coherent states can be prepared remotely by subtracting non-locally a single photon from two quantum superpositions of coherent states, the so-called "Schroedinger's cat" state. Such entanglement can further be distributed over longer distances by successive entanglement swapping operations using linear optics and photon-number resolving detectors. The aim of this paper is to evaluate the performance of this approach to quantum repeaters for long distance quantum communications. Despite many attractive features at first sight, we show that, when using state-of-the-art photon counters and quantum memories, they do not achieve higher entanglement generation rates than repeaters based on single-photon entanglement. We discuss potential developments which may take better advantage of the richness of entanglement based on continuous variables, including in particular efficient parity measurements.

  5. Limitations on quantum key repeaters.

    Science.gov (United States)

    Bäuml, Stefan; Christandl, Matthias; Horodecki, Karol; Winter, Andreas

    2015-04-23

    A major application of quantum communication is the distribution of entangled particles for use in quantum key distribution. Owing to noise in the communication line, quantum key distribution is, in practice, limited to a distance of a few hundred kilometres, and can only be extended to longer distances by use of a quantum repeater, a device that performs entanglement distillation and quantum teleportation. The existence of noisy entangled states that are undistillable but nevertheless useful for quantum key distribution raises the question of the feasibility of a quantum key repeater, which would work beyond the limits of entanglement distillation, hence possibly tolerating higher noise levels than existing protocols. Here we exhibit fundamental limits on such a device in the form of bounds on the rate at which it may extract secure key. As a consequence, we give examples of states suitable for quantum key distribution but unsuitable for the most general quantum key repeater protocol.

  6. A bis-calixarene from olefin metathesis

    Science.gov (United States)

    Hailu, Shimelis T.; Butcher, Ray J.; Hudrlik, Paul F.; Hudrlik, Anne M.

    2012-01-01

    A ring-closing olefin metathesis reaction of tetra­kis­(all­yl­oxy)calix[4]arene gave the bis­ calixarene, (15E,40E,60E)-65,74-bis­(prop-2-en-1-yl­oxy)-13,18,38,43,58,63-hexa­oxado­deca­cyclo­[28.26.8.720,36.111,45.151,55.05,57.07,12.019,24.026,64.032,37.044,49.168,72]tetra­hepta­conta-1,3,5(57),7,9,11,15,19(24),20,22,26,28,30(64),32,34,36,40,44(49),45,47,51,53,55(65),60,68,70,72(74)-hepta­cosa­ene, C74H68O8. It is a cage formed from two calix[4]arene units joined by butenyl groups at three of the O atoms on the narrow rim. The fourth O atom on each calixarene unit is joined with an allyl group. Each of the calix[4]arene units has a flattened cone conformation in which the all­yloxy-substituted aryl group and the opposite aryl group are close together and almost parallel [dihedral angle between planes = 1.09 (11)°], and the other two aryl groups are splayed outward [dihedral angle between planes = 79.53 (11)°]. No guest mol­ecule (e.g. solvent) was observed within the cage. The alkene C atoms of one of the links between the calixarene moieties are disordered over two orientations with occupancies of 0.533 (9) and 0.467 (9). PMID:22719604

  7. A bis-calixarene from olefin metathesis.

    Science.gov (United States)

    Hailu, Shimelis T; Butcher, Ray J; Hudrlik, Paul F; Hudrlik, Anne M

    2012-06-01

    A ring-closing olefin metathesis reaction of tetra-kis-(all-yl-oxy)calix[4]arene gave the bis- calixarene, (15E,40E,60E)-65,74-bis-(prop-2-en-1-yl-oxy)-13,18,38,43,58,63-hexa-oxado-deca-cyclo-[28.26.8.7(20,36).1(11,45).1(51,55).0(5,57).0(7,12).0(19,24).0(26,64).0(32,37).0(44,49).1(68,72)]tetra-hepta-conta-1,3,5(57),7,9,11,15,19(24),20,22,26,28,30(64),32,34,36,40,44(49),45,47,51,53,55(65),60,68,70,72(74)-hepta-cosa-ene, C(74)H(68)O(8). It is a cage formed from two calix[4]arene units joined by butenyl groups at three of the O atoms on the narrow rim. The fourth O atom on each calixarene unit is joined with an allyl group. Each of the calix[4]arene units has a flattened cone conformation in which the all-yloxy-substituted aryl group and the opposite aryl group are close together and almost parallel [dihedral angle between planes = 1.09 (11)°], and the other two aryl groups are splayed outward [dihedral angle between planes = 79.53 (11)°]. No guest mol-ecule (e.g. solvent) was observed within the cage. The alkene C atoms of one of the links between the calixarene moieties are disordered over two orientations with occupancies of 0.533 (9) and 0.467 (9).

  8. Growth and characterization of pure and Ferrous sulphate doped Bis thiourea zinc chloride

    Directory of Open Access Journals (Sweden)

    Mrs.M.Jaya Brabha

    2015-10-01

    Full Text Available Non linear optical material has wide applications in the area of optical devices. That device mainly used to measure electromagnetic radiation. Single crystals of pure Bis thiourea Zinc chloride and Ferrous sulphate doped Bis thiourea Zinc chloride were grown by slow evaporation technique. The grown crystals have been subjected to powder X-ray diffraction to determine the crystalline size and unit cell parameter. The incorporation of ferrous sulphate in BTZC was confirmed by the EDAX and FTIR analysis. UV-Visible spectrum shows that the grown crystals have wide optical transparency in the entire visible region. The thermo gravimetric analysis suggests that incorporation of ferrous sulphate in the BTZC decreases the thermal stability of the grown crystal.

  9. Photovoltaic and photophysical properties of a novel bis-3-hexylthiophene substituted quinoxaline derivative

    Energy Technology Data Exchange (ETDEWEB)

    Guenes, Serap [Linz Institute for Organic Solar Cells (LIOS), Johannes Kepler University Linz, Physical Chemistry, Altenberger Strasse 69, A-4040 Linz (Austria); Yildiz Technical University, Faculty of Arts and Science, Department of Physics, Davutpasa Campus, 34210 Esenler, Istanbul (Turkey); Baran, Derya; Guenbas, Goerkem; Oezyurt, Funda; Toppare, Levent [Middle East Technical University, Faculty of Arts and Science, Department of Chemistry, 06531 Ankara (Turkey); Fuchsbauer, Anita; Sariciftci, Niyazi Serdar [Linz Institute for Organic Solar Cells (LIOS), Johannes Kepler University Linz, Physical Chemistry, Altenberger Strasse 69, A-4040 Linz (Austria)

    2008-09-15

    We report on the photophysical properties and photovoltaic performance of a polythiophene derivative, poly-2,3-bis(4-tert-butylphenyl)-5,8-bis(4-hexylthiophen-2-yl)quinoxaline (PHTQ) as an electron donor in bulk heterojunction solar cells blended with the acceptor 1-(3-methoxycarbonyl)propyl-1-phenyl-[6,6]-methanofullerene (PCBM). Devices were composed of PHTQ and varying amounts of PCBM (1:1, 1:2, 1:3, 1:4 w-w ratio). The components were spin cast from ortho-dichlorobenzene (ODCB) and characterized by measuring current-voltage characteristics under simulated AM 1.5 conditions. Efficiencies up to 0.3% have been reached. Incident photon to current efficiency (IPCE) is reported and the nanoscale morphology was investigated with atomic force microscopy (AFM). Photoinduced absorption spectroscopy confirms the photoinduced charge transfer in such donor acceptor blends. (author)

  10. Bis-naphtho-γ-pyrones from Fungi and Their Bioactivities

    Directory of Open Access Journals (Sweden)

    Shiqiong Lu

    2014-05-01

    Full Text Available Bis-naphtho-γ-pyrones are an important group of aromatic polyketides derived from fungi. They have a variety of biological activities including cytotoxic, antitumor, antimicrobial, tyrosine kinase and HIV-1 integrase inhibition properties, demonstrating their potential applications in medicine and agriculture. At least 59 bis-naphtho-γ-pyrones from fungi have been reported in the past few decades. This mini-review aims to briefly summarize their occurrence, biosynthesis, and structure, as well as their biological activities. Some considerations regarding to synthesis, production, and medicinal and agricultural applications of bis-naphtho-γ-pyrones are also discussed.

  11. Impact of food and fluid intake on technical and biological measurement error in body composition assessment methods in athletes.

    Science.gov (United States)

    Kerr, Ava; Slater, Gary J; Byrne, Nuala

    2017-02-01

    Two, three and four compartment (2C, 3C and 4C) models of body composition are popular methods to measure fat mass (FM) and fat-free mass (FFM) in athletes. However, the impact of food and fluid intake on measurement error has not been established. The purpose of this study was to evaluate standardised (overnight fasted, rested and hydrated) v. non-standardised (afternoon and non-fasted) presentation on technical and biological error on surface anthropometry (SA), 2C, 3C and 4C models. In thirty-two athletic males, measures of SA, dual-energy X-ray absorptiometry (DXA), bioelectrical impedance spectroscopy (BIS) and air displacement plethysmography (BOD POD) were taken to establish 2C, 3C and 4C models. Tests were conducted after an overnight fast (duplicate), about 7 h later after ad libitum food and fluid intake, and repeated 24 h later before and after ingestion of a specified meal. Magnitudes of changes in the mean and typical errors of measurement were determined. Mean change scores for non-standardised presentation and post meal tests for FM were substantially large in BIS, SA, 3C and 4C models. For FFM, mean change scores for non-standardised conditions produced large changes for BIS, 3C and 4C models, small for DXA, trivial for BOD POD and SA. Models that included a total body water (TBW) value from BIS (3C and 4C) were more sensitive to TBW changes in non-standardised conditions than 2C models. Biological error is minimised in all models with standardised presentation but DXA and BOD POD are acceptable if acute food and fluid intake remains below 500 g.

  12. Corrosion Inhibition Effect of 4-(2-Diethylamino-Ethylsulfonyl-Phthalonitrile and 4,5-Bis(Hexylsulfonyl-Phthalonitrile

    Directory of Open Access Journals (Sweden)

    Esma Sezer

    2011-01-01

    Full Text Available Inhibition of stainless steel corrosion in a 3.0 M NaCl solution by 4-(2-diethylamino-ethylsulfanyl-phthalonitrile (DAESPN and 4,5-bis(hexylsulfonyl-phthalonitrile (Bis-HSPN was investigated by polarization and electrochemical impedance spectroscopy (EIS measurements. The values of cathodic (βc and anodic (βa Tafel slopes, corr, corr, corrosion rate (CR, and inhibition efficiences (IE% obtained from polarization curves and polarization resistance (P, double-layer capacitance (dl, specific capacitance (sp values were obtained from EIS. Double-layer capacitance differences in the presence and absence of inhibitors were also obtained from EIS measurements as suggested in the literature in order to investigate the interaction of them with metal surface. Results show that both DAESPN and Bis-HSPN are effective in cathodic reaction. Impedance measurements suggest higher surface coverage for DAESPN. The interaction between the inhibitor and the stainless steel was investigated by the adsorption isotherm. Langmuir adsorption isotherm ads was applied and Δ values were obtained and found as 4.32×10−4, 1.17×10−4 and 9.2 kJ, 12.5 kJ for DAESPN and Bis-HSPN, respectively, which suggests the electrostatic interaction between charged metal surface and charged organic molecules.

  13. EAMJ Dec. Repeatability.indd

    African Journals Online (AJOL)

    2008-12-12

    Dec 12, 2008 ... Results:Kappa values for four-week repeatability for the wheeze and asthma questions were 0.61 ... for logistic, cultural and ethical reasons, to use ... individual with baseline forced expiratory volume in .... period is likely to also include the effects of true ... data, the writing of the manuscript or the decision.

  14. Metabolic control analysis of the penicillin biosynthetic pathway: the influence of the LLD-ACV:bisACV ratio on the flux control.

    Science.gov (United States)

    Theilgaard, H A; Nielsen, J

    1999-01-01

    An extended kinetic model for the first two steps of the penicillin biosynthetic pathway in Penicillium chrysogenum is set up. It includes the formation and reduction of the dimer bis-delta-(L-alpha-aminoadipyl)-L-cysteinyl-D-valine (bisACV) from the first pathway intermediate LLD-ACV and their parallel inhibition of the enzyme ACV synthetase (ACVS). The kinetic model is based on Michaelis-Menten type kinetics, with non-competitive inhibition of the ACVS by both LLD-ACV and bisACV, and competitive inhibition of the isopenicillin N synthetase (IPNS) by glutathione. The inhibition constant of LLD-ACV, KACV is determined to be 0.54 mm. With the kinetic model metabolic control analysis is performed to identify the distribution of rate-control in the pathway at all ratios of LLD-ACV:bisACV. It is concluded that the flux control totally resides at the IPNS. This is a result of the regulation of the ACVS by both the LLD-ACV and bisACV demanding a higher flux through the IPNS enzyme to alleviate their inhibition. The measurement of an intracellular ratio of LLD-ACV:bisACV to be in the range of 1-2 moles per moles emphasises the importance of a fast conversion of LLD-ACV to IPN, and accumulation of LLD-ACV above the K(m)-value of the IPNS should therefore be avoided.

  15. Synthesis and Bioactivities of A Series of Bis-azoles

    Institute of Scientific and Technical Information of China (English)

    ZHOU Cheng-He; LIU Qiang; CHEN Jie; HU Xiang-Nan; CAI Meng-Shen; XIE Ru-Gang; Alfred Hassner

    2003-01-01

    @@ Imidazoles as pharmaceutical agents are widely used and investigated. A series of bis-azoles were prepared fromimidazole and its analogues and dibromides obtained according to similar procedures of literatures. [1 ~ 4

  16. 数控机床加工在机检测测量头的精准重复定位机构设计%Design of Precisely Repeat Positioning Mechanism for On-machine Measurement Measuring-head of CNC Machine Tool Manufacturing

    Institute of Scientific and Technical Information of China (English)

    陆东明

    2016-01-01

    通过对测量头测量感应技术和无线数据传输技术以及数控机床控制系统信号传输原理的研究,为达到测量头重复定位精度为1μm,设计了磁体组件,利用磁感应力使测量杆精准复位。用此测量头在数控机床上测量直径30 mm标准钢球,经过连续5万次测试,由计算机宏程序软件运算得出的钢球直径数值差异在1μm,符合精密测量工具精度要求。%Based on the research of measuring head sensing technology, wireless data transmission technology and CNC machine tool control signal transmission principle, a set of magnetic subassembly, which utilized the force caused by magnetic induction to reset measuring rod precisely, was designed to achieve repeat positioning accuracy within 1 μm for measuring head.Such measuring head equipped with magnetic subassembly was tested to measure diameter 30 mm standard steel balls on CNC machine tool.After 50 000 times continuously test, the steel ball diameter difference calculated and analyzed by macro program of computer software was controlled less than 1μm.The Testing results prove that the accuracy meets requirements.

  17. Repeatability of Response to Asthma Medications

    Science.gov (United States)

    Wu, Ann; Tantisira, Kelan; Li, Lingling; Schuemann, Brooke; Weiss, Scott

    2010-01-01

    Background Pharmacogenetic studies of drug response in asthma assume that patients respond consistently to a treatment but that treatment response varies across patients, however, no formal studies have demonstrated this. Objective To determine the repeatability of commonly used outcomes for treatment response to asthma medications: bronchodilator response, forced expiratory volume in 1 second (FEV1), and provocative concentration of methacholine producing a 20% decline in FEV1 (PC20). Methods The Childhood Asthma Management Program (CAMP) was a multi-center clinical trial of children randomized to receiving budesonide, nedocromil, or placebo. We determined the intraclass correlation coefficient (ICC) for each outcome over repeated visits over four years in CAMP using mixed effects regression models. We adjusted for the covariates: age, race/ethnicity, height, family income, parental education, and symptom score. We incorporated each outcome for each child as repeated outcome measurements and stratified by treatment group. Results The ICC for bronchodilator response was 0.31 in the budesonide group, 0.35 in the nedocromil group, and 0.40 in the placebo group, after adjusting for covariates. The ICC for FEV1 was 0.71 in the budesonide group, 0.60 in the nedocromil group, and 0.69 in the placebo group, after adjusting for covariates. The ICC for PC20 was 0.67 in the budesonide and placebo groups and 0.73 in the nedocromil group, after adjusting for covariates. Conclusion The within treatment group repeatability of FEV1 and PC20 are high; thus these phenotypes are heritable. FEV1 and PC20 may be better phenotypes than bronchodilator response for studies of treatment response in asthma. PMID:19064281

  18. Frequency Bandwidth of Half-Wave Impedance Repeater

    Directory of Open Access Journals (Sweden)

    Marek Dvorsky

    2012-01-01

    Full Text Available This article brings in the second part general information about half-wave impedance repeater. The third part describes the basic functional principles of the half-wave impedance repeater using Smith chart. The main attention is focused in part four on the derivation of repeater frequency bandwidth depending on characteristics and load impedance of unknown feeder line. Derived dependences are based on the elementary features of the feeder lines with specific length. The described functionality is proved in part 4.3 by measurement of transformed impedance using vector several unbalanced feeder lines and network analyzer VNWA3+.

  19. 40 CFR 721.8100 - Potassium N,N-bis (hydroxy-ethyl) cocoamine oxide phosphate, and potassium N,N-bis (hy-droxy...

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Potassium N,N-bis (hydroxy-ethyl) cocoamine oxide phosphate, and potassium N,N-bis (hy-droxy-ethyl) tal-lo-wa-mine oxide phos-phate. 721.8100... Substances § 721.8100 Potassium N,N-bis (hydroxy-ethyl) cocoamine oxide phosphate, and potassium N,N-bis...

  20. Adaptación del Cuestionario de Personalidad BIS BAS IPIP a una muestra de estudiantes universitarios argentinos y análisis de su relación con patrones de consumo de alcohol

    National Research Council Canada - National Science Library

    Maria Victoria Martinez; Mauricio Federico Zalazar Jaime; Angelina Pilatti; Marcos Cupani

    2012-01-01

    The aim of this study was to adapt to a sample of Argentine students the Personality Questionnaire IPIP BIS BAS and to obtain a personality measure that allows discrimination among different patterns...

  1. Hippocampal volume is positively associated with behavioural inhibition (BIS) in a large community-based sample of mid-life adults: the PATH through life study.

    Science.gov (United States)

    Cherbuin, Nicolas; Windsor, Tim D; Anstey, Kaarin J; Maller, Jerome J; Meslin, Chantal; Sachdev, Perminder S

    2008-09-01

    The fields of personality research and neuropsychology have developed with very little overlap. Gray and McNaughton were among the first to recognize that personality traits must have neurobiological correlates and developed models relating personality factors to brain structures. Of particular note was their description of associations between conditioning, inhibition and activation of behaviours, and specific neural structures such as the hippocampus, amygdala and the prefrontal cortex. The aim of this study was to determine whether personality constructs representing the behavioural inhibition and activation systems (BIS/BAS) were associated with volumetric measures of the hippocampus and amygdala in humans. Amygdalar and hippocampal volumes were measured in 430 brain scans of cognitively intact community-based volunteers. Linear associations between brain volumes and the BIS/BAS measures were assessed using multiple regression, controlling for age, sex, education, intra-cranial and total brain volume. Results showed that hippocampal volumes were positively associated with BIS sensitivity and to a lesser extent with BAS sensitivity. No association was found between amygdalar volume and either the BIS or BAS. These findings add support to the model of Gray and McNaughton, which proposes a role of the hippocampus in the regulation of defensive/approach behaviours and trait anxiety but suggest an absence of associations between amygdala volume and BIS/BAS measures.

  2. Directionality switchable gain stabilized linear repeater

    Science.gov (United States)

    Ota, Takayuki; Ohmachi, Tadashi; Aida, Kazuo

    2004-10-01

    We propose a new approach to realize a bidirectional linear repeater suitable for future optical internet networks and fault location in repeater chain with OTDR. The proposed approach is the linear repeater of simple configuration whose directionality is rearranged dynamically by electrical control signal. The repeater is composed of a magneto-optical switch, a circulator, a dynamically gain stabilized unidirectional EDFA, and control circuits. The repeater directionality is rearranged as fast as 0.1ms by an electrical control pulse. It is experimentally confirmed that OTDR with the directionality switchable repeater is feasible for repeater chain. The detailed design and performance of the repeater are also discussed, including the multi-pass interference (MPI) which may arise in the proposed repeater, the effect of the MPI on SNR degradation of the repeater chain and the feed-forward EDFA gain control circuit.

  3. A review on bis-hydrazonoyl halides: Recent advances in their synthesis and their diverse synthetic applications leading to bis-heterocycles of biological interest

    Directory of Open Access Journals (Sweden)

    Ahmad Sami Shawali

    2016-11-01

    Full Text Available This review covers a summary of the literature data published on the chemistry of bis-hydrazonoyl halides over the last four decades. The biological activities of some of the bis-heterocyclic compounds obtained from these bis-hydrazonoyl halides are also reviewed and discussed.

  4. Formation and Characterization of Mixed Crystals Based on Bis (Thiourea)Cadmium Chloride and Bis (Thiourea)Cadmium Iodide

    OpenAIRE

    2014-01-01

    Bis(thiourea)cadmium chloride(BTCC) and bis(thiourea)cadmium iodide (BTCI) are metal complexes of thiourea having better nonlinear optical properties than KH2PO4. An attempt has been made in the present study to form mixed crystals based on BTCC and BTCI (even though their crystal lattices mismatch) from aqueous solutions, the precursors mixed in proper proportions. A total of seven (including the end members) crystals were formed by the free evaporation method and characteriz...

  5. Oxygen uptake during repeated-sprint exercise.

    Science.gov (United States)

    McGawley, Kerry; Bishop, David J

    2015-03-01

    Repeated-sprint ability appears to be influenced by oxidative metabolism, with reductions in fatigue and improved sprint times related to markers of aerobic fitness. The aim of the current study was to measure the oxygen uptake (VO₂) during the first and last sprints during two, 5 × 6-s repeated-sprint bouts. Cross-sectional study. Eight female soccer players performed two, consecutive, 5 × 6-s maximal sprint bouts (B1 and B2) on five separate occasions, in order to identify the minimum time (trec) required to recover total work done (Wtot) in B1. On a sixth occasion, expired air was collected during the first and last sprint of B1 and B2, which were separated by trec. The trec was 10.9 ± 1.1 min. The VO₂ during the first sprint was significantly less than the last sprint in each bout (psprint (measured in kJ) was significantly related to VO₂max in both B1 (r=0.81, p=0.015) and B2 (r=0.93, p=0.001). In addition, the VO₂ attained in the final sprint was not significantly different from VO₂max in B1 (p=0.284) or B2 (p=0.448). The current study shows that the VO₂ increases from the first to the last of 5 × 6-s sprints and that VO₂max may be a limiting factor to performance in latter sprints. Increasing V˙O₂max in team-sport athletes may enable increased aerobic energy delivery, and consequently work done, during a bout of repeated sprints. Copyright © 2014 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  6. Contemporary carbon content of bis (2-ethylhexyl) phthalate in butter.

    Science.gov (United States)

    Tong, T; Ondov, J M; Buchholz, B A; VanDerveer, M C

    2016-01-01

    The fraction of naturally produced bis (2-ethylhexyl) phthalate (DEHP), a ubiquitous plasticizer known to contaminate packaged foods, was determined for each of five 1.10 kg samples of unsalted market butter by accelerator mass spectrometry (AMS). After extraction and concentration enrichment with liquid-liquid extraction, flash column chromatography, and preparative-scale high performance liquid chromatography, each sample provided ≈ 250 μg extracts of DEHP with carbon purity ranging from 92.5 ± 1.2% (n = 3, 1σ) to 97.1 ± 0.8% (n = 3, 1σ) as measured with gas chromatography mass spectrometry (GC-MS). After corrections for method blank DEHP, co-eluting compounds, and unidentified carbon, the mean fraction of naturally produced DEHP in butter was determined to be 0.16 ± 0.12 (n = 5, 1σ). To our knowledge, this is the first report of the contemporary fraction of DEHP isolated from market butter in the U.S.

  7. Synthesis, properties and supramolecular structure of di(aqua)bis(ethylenediamine)nickel(II) bis(4-nitrobenzoate)

    Indian Academy of Sciences (India)

    Bikshandarkoil R Srinivasan; Gayatri K Rane

    2009-03-01

    The reaction of the sodium salt of 4-nitrobenzoic acid (4-nbaH) with [Ni(H2O)6]Cl2 or [Ni(en)3]Cl2.2H2O (en is ethylenediamine) results in the formation of the known octahedral compound [Ni(H2O)4(1-4-nba)2].2H2O (4-nba = 4-nitrobenzoate) 1 or the title compound di(aqua)bis(ethylenediamine) nickel(II) bis(4-nitrobenzoate) 2 respectively. Compounds 1 and 2 were characterized by elemental analysis, infrared spectra, DSC thermograms, weight loss studies and the structure of 2 was determined. Both 1 and 2 can be thermally decomposed to green NiO. The title compound [Ni(H2O)2(en)2](4-nba)2 2 crystallizes in the centrosymmetric monoclinic space group 21/ with the Ni(II) situated on an inversion center. The crystal structure of 2 consists of a hexacoordinated Ni(II) complex cation and an uncoordinated 4-nba anion. In the octahedral complex cation, the central metal is linked to two symmetry related bidentate en ligands and two water molecules. In the crystal structure, the cations and anions are linked by three varieties of hydrogen bonding interactions. A comparative study of seven nickel 4-nitrobenzoate compounds is described.

  8. Estructura molecular y cristalina del bis (bis(dietilamino glioximato níquel (II

    Directory of Open Access Journals (Sweden)

    Luis Alejandro Nuvan

    2009-07-01

    Full Text Available Ni(CioH2lN4022- monoclínico, grupo espacial P2i/a, a = 15.760 (2, b = 11.793 (3, c = 7.297 (1 A°, j3 = 99.10 (1°, V = 1339.0 (7 A°3, Z = 2 , De = 1.28 Mg M " \\ M = 765 M " ' . La estructura fue resuelta por el método del átomo pesado y afinada por mínimos cuadrados, utilizando la matriz completa, hasta obtener una concordancia R = 0.068 para todas las reflexiones observadas. El átomo de níquel está localizado en un centro de inversión y presenta una coordinación cuadrado planar. El complejo Bis (Bis (Dietilamino Glioximato Níquel (II es casi planar y el desplazamiento de los grupos etil con respecto al plano es producido por efectos estéricos. Las moléculas planares se apilan a lo largo de c, las normales a los planos forman con este eje un ángulo de 41.53 . Existen interacciones axiales entre el níquel y los grupos amino de las moléculas adyacentes de la columna.

  9. Origin and fate of repeats in bacteria.

    Science.gov (United States)

    Achaz, G; Rocha, E P C; Netter, P; Coissac, E

    2002-07-01

    We investigated 53 complete bacterial chromosomes for intrachromosomal repeats. In previous studies on eukaryote chromosomes, we proposed a model for the dynamics of repeats based on the continuous genesis of tandem repeats, followed by an active process of high deletion rate, counteracted by rearrangement events that may prevent the repeats from being deleted. The present study of long repeats in the genomes of Bacteria and Archaea suggests that our model of interspersed repeats dynamics may apply to them. Thus the duplication process might be a consequence of very ancient mechanisms shared by all three domains. Moreover, we show that there is a strong negative correlation between nucleotide composition bias and the repeat density of genomes. We hypothesise that in highly biased genomes, non-duplicated small repeats arise more frequently by random effects and are used as primers for duplication mechanisms, leading to a higher density of large repeats.

  10. Airborne Radar Interferometric Repeat-Pass Processing

    Science.gov (United States)

    Hensley, Scott; Michel, Thierry R.; Jones, Cathleen E.; Muellerschoen, Ronald J.; Chapman, Bruce D.; Fore, Alexander; Simard, Marc; Zebker, Howard A.

    2011-01-01

    Earth science research often requires crustal deformation measurements at a variety of time scales, from seconds to decades. Although satellites have been used for repeat-track interferometric (RTI) synthetic-aperture-radar (SAR) mapping for close to 20 years, RTI is much more difficult to implement from an airborne platform owing to the irregular trajectory of the aircraft compared with microwave imaging radar wavelengths. Two basic requirements for robust airborne repeat-pass radar interferometry include the ability to fly the platform to a desired trajectory within a narrow tube and the ability to have the radar beam pointed in a desired direction to a fraction of a beam width. Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR) is equipped with a precision auto pilot developed by NASA Dryden that allows the platform, a Gulfstream III, to nominally fly within a 5 m diameter tube and with an electronically scanned antenna to position the radar beam to a fraction of a beam width based on INU (inertial navigation unit) attitude angle measurements.

  11. Optical and magneto-optical properties of spin coated films of novel trinuclear bis(oxamato) and bis(oxamidato) type complexes

    Science.gov (United States)

    Abdulmalic, Mohammad A.; Fronk, Michael; Bräuer, Björn; Zahn, Dietrich R. T.; Salvan, Georgeta; Eya‧ane Meva, Francois; Rüffer, Tobias

    2016-12-01

    This work reports the first example of the spectroscopic measurements of the Magneto-Optical Kerr Effect (MOKE) of films being composed of trinuclear transition metal complexes on a non-transparent substrate at room temperature. The thin films of the tailor-made trinuclear bis(oxamidato) type complex 5 ([Cu3(opbonPr2)(tmcd)2(NO3)2], opbonPr2 = o-phenylenebis(N'-npropyloxamido, tmcd=trans-(1 R,2 R)-N,N,N‧,N‧-tetramethyl-cyclohexanediamine) and of the bis(oxamato) type complexes 11 ([Cu2Ni(opbaCF3)(pmdta)2(NO3)2], opbaCF3 = 4-trifluoromethyl-o-phenylenebis(oxamato), pmdta = N,N,N,‧N″,N″-pentamethyldiethylenetriamine) and 12 ([Cu3(opba)(bppe)2(NO3)2] (opba = o-phenylenebis(oxamato), bppe = S-N,N-bis(2-picolyl)-1-phenylethylamine) were fabricated by spin-coating and their thicknesses in the range between 0.5 μm and 2 μm was determined by spectroscopic ellipsometry. Based on the spectroscopic ellipsometry results it was also possible to determine the optical constants of the film and compare them with the absorption of the complexes in solution in order to confirm the complex integrity after the film deposition. The fabrication of high-quality films which exhibit Kerr rotation up to 0.2 mrad (11.5 mdeg) was only possible due to tailor-made synthesis, which allows circumventing intermolecular interactions of the trinuclear complexes during the film formation.

  12. [The influence of intermittent hemodialysis (HD) on bispectral index (scale) (BIS) and serum propofol concentration under postoperative intravenous sedation].

    Science.gov (United States)

    Tatebayashi, Shigeru; Imai, Yuichiro; Ohgi, Kazuhiko; Tamaki, Shigehiro; Yamamoto, Kazuhiko; Takahashi, Masahiro; Kurehara, Koukichi; Furuya, Hitoshi; Kirita, Tadaaki

    2004-05-01

    We experienced a case of postoperative intravenous sedation with propofol during intermittent hemodialysis (HD), and investigated the correlation between the clinical sedation level based on bispectral index scale (BIS) together with Ramsay score, and the serum concentration of propofol. One adult oral cancer patient (carcinoma of the lower gingiva) with end-stage renal dysfunction needing HD was selected for this study. The day after operation, HD was commenced under intravenous sedation with propofol. Clinical sedation level was assessed using BIS and Ramsay score, and serum propofol concentrations were determined in arterial blood samples. Serum concentrations were measured every 15 times until 51 hours after operation. The initial dose of propofol was set at 3.5 mg x kg(-1) x h(-1) on the basis of clinical symptoms. According to BIS and Ramsay score, sedation level decreased lineally for 1 hour after commencement of HD. In contrast, serum propofol concentration incresed from 1.71 microg x ml(-1) to 2.21 microg x ml(-1). Total serum concentration of propofol was enhanced during HD because of dialytic dehydration, but, according to BIS and Ramsay scores, the possibility was suggested that the fraction of albmin-unbound propofol with pharmacological activities was eliminated or absorbed by membrane during HD.

  13. A New Synthetic Route for 3,3'-Bis(fluorodinitromethyl)difurazanyl Ether (FOF-13) and Its Energetic Properties

    Science.gov (United States)

    Zhai, Lianjie; Wang, Bozhou; Xu, Kangzheng; Huo, Huan; Liu, Ning; Li, Yanan; Li, Hui; Lian, Peng; Fan, Xuezhong

    2016-01-01

    A new protocol for preparation of 3,3-bis(fluorodinitromethyl)difurazanyl ether (FOF-13) was developed. It involves (i) nitration of 3,3'-bis(chlorohydroxyminomethyl)difurazanyl ether with N2O5/MeCN to give 3,3-bis(chlorodinitromethyl)difurazanyl ether (4), (ii) reduction of 4 with KI/MeOH to obtain potassium salt of 3,3'-bis(dinitromethyl)difurazanyl ether (6) and (iii) fluorination of 6 with XeF2 in anhydrous acetonitrile to form the desired FOF-13. FOF-13 was fully characterized by IR, 13C NMR, 19F NMR, and elemental analysis. FOF-13 exhibits excellent physicochemical and detonation properties, such as high density (1.91 g cm‒3), good thermal stability, reasonable impact sensitivity (14 J) and friction sensitivity (64%), high measured detonation velocity (8497 m s‒1 at 1.69 g cm‒3). Furthermore, the precursors 4 and 6 were developed for the first time.

  14. Physical and chemical properties of an antimicrobial Bis-GMA free dental resin with quaternary ammonium dimethacrylate monomer.

    Science.gov (United States)

    Huang, Qi-ting; He, Jing-wei; Lin, Zheng-mei; Liu, Fang; Lassila, Lippo V J; Vallittu, Pekka K

    2016-03-01

    The objective of this study was to evaluate the antibacterial activity, physicochemical properties of the quaternary ammonium dimethacrylate monomer N,N-bis[2-(3-(methacryloyloxy)propanamido)-ethyl]-N-methylhexadecyl ammonium bromide (IMQ-16) containing diurethane dimethacrylate (UDMA)/tricyclodecane dimethanol diacrylate (SR833s) resin system and compare with bisphenylglycidyl dimethacrylate (Bis-GMA)/triethylene glycol dimethacrylate (TEGDMA) resin system. It was hypothesized that the physical and chemical properties of the experimental polymers would be comparable with Bis-GMA/TEGDMA polymer and IMQ-16 monomer could endow the UDMA/SR833s resin with antibacterial activity. Double bond conversion (DC) was measured using Fourier transform infrared spectroscopy (FTIR). Mechanical properties including flexural strength (FS) and flexural modulus (FM) were measured by three-point bending test with bars of 2mm×2mm×25mm. Water sorption (WS) and solubility (WSL) were also investigated. Antibacterial activity of obtained polymers against Streptococcus mutans Ingbitt (S. mutans) was tested through direct contact test (DCT). The presence of antibacterial activity due to soluble components was also investigated by agar diffusion test (ADT). All of the polymers containing IMQ-16 exhibited improvements in WS and WSL, while maintaining equivalent DC and FS relative to the Bis-GMA/TEGDMA control system. Incorporation of 17% and 20% of IMQ-16 into UDMA/SR833s resin reduced the viable counts of S. mutans after incubation on the surface of the materials and produced no inhibition zones around the cured discs in ADT. UDMA/SR833s resin system is promising to formulate an antibacterial polymer with equivalent or even higher physicochemical properties relative to Bis-GMA/TEGDMA formulation. IMQ-16 is capable to endow UDMA/SR833s resin system with significant antibacterial activity when the mass ratio is 17% or 20%.

  15. Improving repeatability by improving quality

    Energy Technology Data Exchange (ETDEWEB)

    Ronen, Shuki; Ackers, Mark; Schlumberger, Geco-Prakla; Brink, Mundy

    1998-12-31

    Time lapse (4-D) seismic is a promising tool for reservoir characterization and monitoring. The method is apparently simple: to acquire data repeatedly over the same reservoir, process and interpret the data sets, then changes between the data sets indicate changes in the reservoir. A problem with time lapse seismic data is that reservoirs are a relatively small part of the earth and important reservoir changes may cause very small differences to the time lapse data. The challenge is to acquire and process economical time lapse data such that reservoir changes can be detected above the noise of varying acquisition and environment. 7 refs., 9 figs.

  16. Coordinated hybrid automatic repeat request

    KAUST Repository

    Makki, Behrooz

    2014-11-01

    We develop a coordinated hybrid automatic repeat request (HARQ) approach. With the proposed scheme, if a user message is correctly decoded in the first HARQ rounds, its spectrum is allocated to other users, to improve the network outage probability and the users\\' fairness. The results, which are obtained for single- and multiple-antenna setups, demonstrate the efficiency of the proposed approach in different conditions. For instance, with a maximum of M retransmissions and single transmit/receive antennas, the diversity gain of a user increases from M to (J+1)(M-1)+1 where J is the number of users helping that user.

  17. Application of UAV-SfM photogrammetry and aerial lidar to a disastrous flood: repeated topographic measurement of a newly formed crevasse splay of the Kinu River, central Japan

    Science.gov (United States)

    Izumida, Atsuto; Uchiyama, Shoichiro; Sugai, Toshihiko

    2017-09-01

    Geomorphic impacts of a disastrous crevasse splay that formed in September 2015 and its post-formation modifications were quantitatively documented by using repeated, high-definition digital surface models (DSMs) of an inhabited and cultivated floodplain of the Kinu River, central Japan. The DSMs were based on pre-flood (resolution: 2 m) and post-flood (resolution: 1 m) aerial light detection and ranging (lidar) data from January 2007 and September 2015, respectively, and on structure-from-motion (SfM) photogrammetry data (resolution: 3.84 cm) derived from aerial photos taken by an unmanned aerial vehicle (UAV) in December 2015. After elimination of systematic errors among the DSMs and down-sampling of the SfM-derived DSM, elevation changes on the order of 10-1 m - including not only topography but also growth of vegetation, vanishing of flood waters, and restoration and repair works - were detected. Comparison of the DSMs showed that the volume eroded by the flood was more than twice the deposited volume in the area within 300-500 m of the breached artificial levee, where the topography was significantly affected. The results suggest that DSMs based on a combination of UAV-SfM and lidar data can be used to quantify, rapidly and in rich detail, topographic changes on floodplains caused by floods.

  18. Coordination behavior of new bis Schiff base ligand derived from 2-furan carboxaldehyde and propane-1,3-diamine. Spectroscopic, thermal, anticancer and antibacterial activity studies.

    Science.gov (United States)

    Mohamed, Gehad G; Zayed, Ehab M; Hindy, Ahmed M M

    2015-06-15

    Novel bis Schiff base ligand, [N1,N3-bis(furan-2-ylmethylene)propane-1,3-diamine], was prepared by the condensation of furan-2-carboxaldehyde with propane-1,3-diamine. Its conformational changes on complexation with transition metal ions [Co(II), Ni(II), Cu(II), Mn(II), Cd(II), Zn(II) and Fe(III)] have been studied on the basis of elemental analysis, conductivity measurements, spectral (infrared, (1)H NMR, electronic), magnetic and thermogravimetric studies. The conductance data of the complexes revealed their electrolytic nature suggesting them as 1:2 (for bivalent metal ions) and 1:3 (for Fe(III) ion) electrolytes. The complexes were found to have octahedral geometry based on magnetic moment and solid reflectance measurements. Thermal analysis data revealed the decomposition of the complexes in successive steps with the removal of anions, coordinated water and bis Schiff base ligand. The thermodynamic parameters were calculated using Coats-Redfern equation. The Anticancer screening studies were performed on human colorectal cancer (HCT), hepatic cancer (HepG2) and breast cancer (MCF-7) cell lines. The antimicrobial activity of all the compounds was studied against Gram negative (Escherichia coli and Proteus vulgaris) and Gram positive (Bacillus vulgaris and Staphylococcus pyogones) bacteria. It was observed that the coordination of metal ion has a pronounced effect on the microbial activities of the bis Schiff base ligand. All the metal complexes have shown higher antimicrobial effect than the free bis Schiff base ligand.

  19. Automatization and familiarity in repeated checking

    NARCIS (Netherlands)

    Dek, Eliane C P; van den Hout, Marcel A.; Giele, Catharina L.; Engelhard, Iris M.

    2014-01-01

    Repeated checking paradoxically increases memory uncertainty. This study investigated the underlying mechanism of this effect. We hypothesized that as a result of repeated checking, familiarity with stimuli increases, and automatization of the checking procedure occurs, which should result in decrea

  20. CDC Vital Signs: Preventing Repeat Teen Births

    Science.gov (United States)

    ... file Error processing SSI file Preventing Repeat Teen Births Recommend on Facebook Tweet Share Compartir On this ... Too many teens, ages 15–19, have repeat births. Nearly 1 in 5 births to teens, ages ...

  1. Reduction chemistry of aryl- and alkyl-substituted bis(imino)pyridine iron dihalide compounds: molecular and electronic structures of [(PDI)2Fe] derivatives.

    Science.gov (United States)

    Wile, Bradley M; Trovitch, Ryan J; Bart, Suzanne C; Tondreau, Aaron M; Lobkovsky, Emil; Milsmann, Carsten; Bill, Eckhard; Wieghardt, Karl; Chirik, Paul J

    2009-05-04

    Sodium amalgam reduction of the aryl-substituted bis(imino)pyridine iron dibromide complex, ((Et)PDI)FeBr2 ((Et)PDI = 2,6-(2,6-Et2-C6H3N=CMe)2C5H3N), under a dinitrogen atmosphere in pentane furnished the bis(chelate)iron compound, ((Et)PDI)2Fe. Characterization by X-ray crystallography established a distorted four-coordinate iron center with two kappa2-bis(imino)pyridine ligands. Reducing the steric demands of the imine substituent to either a less sterically encumbered aryl ring (e.g., C6H4-4-OMe) or an alkyl group (e.g., Cy, iPr, cis-myrtanyl) also yielded bis(chelate) compounds from sodium amalgam reduction of the corresponding dihalide. Characterization of the compounds with smaller imine substituents by X-ray diffraction established six-coordinate, pseudo-octahedral compounds. In one case, a neutral bis(chelate)iron compound was prepared by reduction of the corresponding iron dication, [(PDI)2Fe]2+, providing chemical confirmation of electrochemically generated species that were previously reported as too reducing to isolate. Magnetic measurements, metrical parameters from X-ray structures, Mössbauer spectroscopy, and open-shell, broken symmetry DFT calculations were used to establish the electronic structure of both types (four- and six-coordinate) of neutral bis(chelate) compounds. The experimentally observed S = 1 compounds are best described as having high-spin ferrous (S(Fe) = 2) centers antiferromagnetically coupled to two bis(imino)pyridine radical anions. Thus, the two-electron reduction of the diamagnetic, low-spin complex [(PDI)2Fe]2+ to [(PDI)2Fe] is ligand-based with a concomitant spin change at iron.

  2. Expanded complexity of unstable repeat diseases

    OpenAIRE

    Polak, Urszula; McIvor, Elizabeth; Dent, Sharon Y.R.; Wells, Robert D.; Napierala, Marek.

    2012-01-01

    Unstable Repeat Diseases (URDs) share a common mutational phenomenon of changes in the copy number of short, tandemly repeated DNA sequences. More than 20 human neurological diseases are caused by instability, predominantly expansion, of microsatellite sequences. Changes in the repeat size initiate a cascade of pathological processes, frequently characteristic of a unique disease or a small subgroup of the URDs. Understanding of both the mechanism of repeat instability and molecular consequen...

  3. Synthesis and biological study of novel methylene-bis-benzofuranyl-

    Directory of Open Access Journals (Sweden)

    Sanjeeva R. Cherkupally

    2008-12-01

    Full Text Available A series of novel methylene-bis-[1,5]-benzothiazepines 4 and methylene-bis-benzofuranyl-[1,5]-benzothiazepines 5 were prepared by the reaction of methylene-bis-chalcones 3 with 2-aminothiophenolfollowed by the condensation with -bromoacetophenone. The structures of the synthesized compounds wereconfirmed by their IR, 1H, 13C NMR and Mass spectral analyses. All the synthesized compounds were tested fortheir antimicrobial activity against Gram-positive, Gram-negative bacteria and fungi. Among the synthesizedcompounds, the compounds 4f, 4g, 5f and 5g were found to be the most active against Bacillus subtilis, Bacillussphaericus, Staphylococcus aureus, Klebsiella aerogenes and Chromobacterium violaceum. Similarly thesecompounds showed potent antifungal effect against Candida albicans, Aspergillus fumigatus, Trichophytonrubrum, and Trichophyton mentagrophytes. It is interesting to note that the compounds with heterocyclic ringsubstituents at the 4th position of benzothiazepine system displayed notable antibacterial activity, almost equalto that of streptomycin and penicillin.

  4. Bis-chalcones and flavones: synthesis and antimicrobial activity.

    Science.gov (United States)

    Husain, Asif; Rashid, Mohd; Mishra, Ravinesh; Kumar, Deepak

    2013-01-01

    A series of bis-chalcones (3a-g) and their flavones derivatives (4a-g) were synthesized and evaluated for their antimicrobial activity. Bis-chalcones were prepared by condensing 1,1'-(4,6-dihydroxy-1,3-phenylene)diethanone (2) with appropriate aryl aldehydes following Claisen-Schmidt reaction conditions. Oxidative cyclization of bis-chalcones (3a-g) in DMSO in the presence of iodine furnished flavones (4a-g). The synthesized compounds were evaluated for their antibacterial and antifungal actions against some selected microbes. The results of antimicrobial evaluation showed that some of the synthesized compounds were good in their antibacterial and antifungal actions.

  5. Synthesis and Characterization of the Adducts of Bis(O-ethyldithiocarbonatocopper(II with Substituted Pyridines

    Directory of Open Access Journals (Sweden)

    Gurpreet Kour

    2013-01-01

    Full Text Available Monomeric five coordinated adducts of bis(O-ethyldithiocarbonatocopper(II of general formula [Cu(C2H5OCS22(L], [L = 2-, 3-, 4-methylpyridines and 2-, 3-, 4-ethylpyridines] have been synthesized and characterized by elemental analysis, i.r. and electronic spectroscopy, magnetic and conductivity measurements. Analytical results show that the adducts have 1 : 1 stoichiometry. The adducts were found to be paramagnetic and their magnetic moments at room temperature lie within the 1.81–1.94 B.M. range and this indicates the presence of one unpaired electron. All the adducts have distorted square pyramidal geometry.

  6. 47 CFR 97.205 - Repeater station.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Repeater station. 97.205 Section 97.205... SERVICE Special Operations § 97.205 Repeater station. (a) Any amateur station licensed to a holder of a Technician, General, Advanced or Amateur Extra Class operator license may be a repeater. A holder of...

  7. 47 CFR 22.1015 - Repeater operation.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Repeater operation. 22.1015 Section 22.1015... Offshore Radiotelephone Service § 22.1015 Repeater operation. Offshore central stations may be used as repeater stations provided that the licensee is able to maintain control of the station, and in...

  8. Photoinduced charge transfer in donor-acceptor (DA) copolymer: fullerene bis-adduct polymer solar cells.

    Science.gov (United States)

    Kang, Tae Eui; Cho, Han-Hee; Cho, Chul-Hee; Kim, Ki-Hyun; Kang, Hyunbum; Lee, Myounghee; Lee, Sunae; Kim, Bongsoo; Im, Chan; Kim, Bumjoon J

    2013-02-01

    Polymer solar cells (PSCs) consisting of fullerene bis-adduct and poly(3-hexylthiophene) (P3HT) blends have shown higher efficiencies than P3HT:phenyl C(61)-butyric acid methyl ester (PCBM) devices, because of the high-lying lowest unoccupied molecular orbital (LUMO) level of the fullerene bis-adducts. In contrast, the use of fullerene bis-adducts in donor-acceptor (DA) copolymer systems typically causes a decrease in the device's performance due to the decreased short-circuit current (J(SC)) and the fill factor (FF). However, the reason for such poor performance in DA copolymer:fullerene bis-adduct blends is not fully understood. In this work, bulk-heterojunction (BHJ)-type PSCs composed of three different electron donors with four different electron acceptors were chosen and compared. The three electron donors were (1) poly[(4,8-bis-(2-ethylhexyloxy)benzo[1,2-b:4,5-b']dithiophene)-2,6-diyl-alt-(5-octylthieno[3,4-c]pyrrole-4,6-dione)-1,3-diyl] (PBDTTPD), (2) poly[(4,8-bis-(2-ethylhexyloxy)benzo[1,2-b:4,5-b']dithiophene)-2,6-diyl-alt-(4-(2-ethylhexanoyl)-thieno[3,4-b]thiophene)-2,6-diyl] (PBDTTT-C), and (3) P3HT polymers. The four electron acceptors were (1) PCBM, (2) indene-C(60) monoadduct (ICMA), (3) indene-C(60) bis-adduct (ICBA), and (4) indene-C(60) tris-adduct (ICTA). To understand the difference in the performance of BHJ-type PSCs for the three different polymers in terms of the choice of fullerene acceptor, the structural, optical, and electrical properties of the blends were measured by the external quantum efficiency (EQE), photoluminescence, grazing incidence X-ray scattering, and transient absorption spectroscopy. We observed that while the molecular packing and optical properties cannot be the main reasons for the dramatic decrease in the PCE of the DA copolymers and ICBA, the value of the driving force for charge transfer (ΔG(CT)) is a key parameter for determining the change in J(SC) and device efficiency in the DA copolymer- and P3HT-based PSCs in

  9. ProtRepeatsDB: a database of amino acid repeats in genomes

    Directory of Open Access Journals (Sweden)

    Chauhan Virander S

    2006-07-01

    Full Text Available Abstract Background Genome wide and cross species comparisons of amino acid repeats is an intriguing problem in biology mainly due to the highly polymorphic nature and diverse functions of amino acid repeats. Innate protein repeats constitute vital functional and structural regions in proteins. Repeats are of great consequence in evolution of proteins, as evident from analysis of repeats in different organisms. In the post genomic era, availability of protein sequences encoded in different genomes provides a unique opportunity to perform large scale comparative studies of amino acid repeats. ProtRepeatsDB http://bioinfo.icgeb.res.in/repeats/ is a relational database of perfect and mismatch repeats, access to which is designed as a resource and collection of tools for detection and cross species comparisons of different types of amino acid repeats. Description ProtRepeatsDB (v1.2 consists of perfect as well as mismatch amino acid repeats in the protein sequences of 141 organisms, the genomes of which are now available. The web interface of ProtRepeatsDB consists of different tools to perform repeat s; based on protein IDs, organism name, repeat sequences, and keywords as in FASTA headers, size, frequency, gene ontology (GO annotation IDs and regular expressions (REGEXP describing repeats. These tools also allow formulation of a variety of simple, complex and logical queries to facilitate mining and large-scale cross-species comparisons of amino acid repeats. In addition to this, the database also contains sequence analysis tools to determine repeats in user input sequences. Conclusion ProtRepeatsDB is a multi-organism database of different types of amino acid repeats present in proteins. It integrates useful tools to perform genome wide queries for rapid screening and identification of amino acid repeats and facilitates comparative and evolutionary studies of the repeats. The database is useful for identification of species or organism specific

  10. catena-Poly[[[diaquacadmium(II]-bis[μ-3,5-bis(isonicotinamidobenzoato

    Directory of Open Access Journals (Sweden)

    Dai-Zhi Kuang

    2010-10-01

    Full Text Available The title compound, {[Cd(C19H13N4O42(H2O2]·4H2O}n or {[Cd(BBA2(H2O2]·4H2O}n, where BBA is 3,5-bis(isonicotinamidobenzoate, is isotypic with its Mn isologue [Chen et al. (2009. J. Coord. Chem. 62, 2421–2428]. The cation sits on a twofold axis and is six-coordinated in a slightly distorted octahedral geometry; the polyhedra are linked into zigzag chains, which are further connected by N—H...O, O—H...O and O—H...N hydrogen bonds as well as π–π interactions [centroid-centroid distance of 3.639 (2 Å], giving a three-dimensional supramolecular framework.

  11. Bis[μ-N-(tert-butyldimethylsilyl-N-(pyridin-2-ylmethylamido]bis[methylcobalt(II

    Directory of Open Access Journals (Sweden)

    Astrid Malassa

    2012-09-01

    Full Text Available The green title complex, [Co2(CH32(C12H21N2Si2], was obtained from bis{[μ-N-tert-butyldimethylsilyl-N-(pyridin-2-ylmethylamido]chloridocobalt(II} and methyllithium in diethyl ether at 195 K via a metathesis reaction. The dimeric cobalt(II complex exhibits a crystallographic center of inversion in the middle of the Co2N2 ring (average Co—N = 2.050 Å. The CoII atom shows a distorted tetrahedral coordination sphere. The exocyclic Co—N bond length to the pyridyl group shows a similar value of 2.045 (4 Å. The exocyclic methyl group has a rather long Co—C bond length of 2.019 (5 Å.

  12. Bis{2,6-bis[(2-hydroxy-5-methylphenyliminomethyl]pyridine} monohydrate

    Directory of Open Access Journals (Sweden)

    Muhammet Kose

    2011-12-01

    Full Text Available The title compound, 2C21H19N3O2·H2O, was synthesized by a Schiff base condensation of 2,6-diformylpyridine with 2-amino-4-methylphenol in ethanol. In the crystal, two molecules of 2,6-bis[(2-hydroxy-5-methylphenyliminomethyl]pyridine dimerize via hydrogen bonding to a water molecule, which lies on a twofold axis. There are also intramolecular phenol–imine hydrogen bonds. The dimers are further linked via π–π (phenyl–pyridine [centroid–centroid distance = 3.707 (2 Å] and π–π edge-to-edge [3.392 (2 Å] interactions. The dihedral angles between the central ring and the two pendant rings are 11.46 (8 and 2.06 (8° while the pendant rings make a dihedral angle of 10.14 (8°.

  13. Application of multivariate Meta-analytical model in Meta-analysis of repeated measures outcomes%生存资料的二次研究系列之六:多元Meta分析模型在重复测量结局Meta分析中的应用

    Institute of Scientific and Technical Information of China (English)

    孟详喻; 田国祥; 周新雨; 孙竹; 李胜; 曾宪涛

    2016-01-01

    Repeated measures data are one of major data types in medical studies, especially in those related to prognosis. Correlation exists among multiple measures values corresponding to different time points, thus separate analyses for single outcome in secondary studies, e.g. Meta-analysis, should be avoided since bias might be introduced and the multivariate Meta-analysis model which well manages dependence across effect sizes is recommended. In this article, a multivariate Meta-analytical model was presented to merge multiple binary repeated measures outcomes, as well as actualized in R software through example analysis.%目的:重复测量资料是医学研究尤其是预后相关研究中重要的资料类型之一。不同时间点重复测量值之间存在相关性,若在二次研究如Meta分析中分开分析的结果可能存在偏倚,采用多元Meta分析模型能够有效避免因分开分析而导致的偏倚。本文介绍使用多元Meta分析模型合并多个二分类重复测量结局的方法,并通过实例分析演示如何在R软件中实现。

  14. Synthesis,Characterization and Properties of Bis{oxo—bis[heteroaromatic carboxylatodibenzyltin(Ⅳ)]}and Crystal Structure of Bis{oxo—bis[2—furylcarboxylatodibenzyltin(Ⅳ)]}

    Institute of Scientific and Technical Information of China (English)

    YINHan-dong; WANGChuan-hua; WANGYong; MAChun-lin

    2003-01-01

    A series of bis{oxo-bis[heteroaromatic carboxylatodibenzyltin(Ⅳ)]}complexes {[(PhCH2)2Sn·(O2CR)]2O}2[where R=2-furyl,2-(2-furyl)vinyl.2-(5-tert-butyl)furyl.2-thiophenyl,2-pyridinyl,2-pyridinyl,3-pyridinyl,4-pyridinyl,3-indolyl,3-indolylmethyl,3-indolylpropyl]was synthesizde by the reactions of heteroaromatic carboxylic acids with dibenzyltin(Ⅳ) oxide.All the complexes were characterized by elemental analysis,IR,and NMR spectra.The complexes were tested against two human tumour cell lines:MCF-7 and WiDr.The results show that they have higher activities in vitro.The crystal structure of bis{oxo-bis[2-furylcarboxylatodibenzyltin(Ⅳ)]}(1)was determined by X-ray diffraction.The crystal structure of bis{ox-bis [2-furylcarboxylatodibenzyltin(Ⅳ)]}(1) was determined by X-ray diffraction.The crystal belongs to monoclinic space group P21/n,a=1.6641(2)nm,b=1.25073(18)nm,c=1.7193(3)nm,β=101.951(2)°,Z=2.R1=0.0446,ωR2=0.1100,Complex 1 is of a centrosymmetric dimer structre with a four-membered central endo-cyclic Sn2O2 unit in which the bridged oxygen atoms are tri-coordinated.Each bridgde oxygen atom also connects with an exo-cyclic tin atom.The tin atoms are six-coordinated and have a coordination geometry of a monocapped trigonal bipyramid with a very similarly distorted mode.Four carboxylate ligands are divided into two types.The two of the four carboxylate ligands are bidentate and bridged to each pair of exoeach pair of exo-and endo-cyclic tin atoms but each utilized one O atom only.

  15. Poly(N,N'-dichloro-N-ethyl-benzene-1, 3-disulfonamide) and N,N,N',N'-tetrachlorobenzene-1,3-disulfonamide as novel catalytic reagents for synthesis of bis-indolyl, tris-indolyl, di(bis-indolyl), tri(bis-indolyl) and tetra(bis-indolyl)methanes under solid-state, solvent and water conditions

    Energy Technology Data Exchange (ETDEWEB)

    Ghorbani-Vaghei, Ramin [Bu-Ali Sina University, Hamadan (Iran, Islamic Republic of). Faculty of Chemistry. Dept. of Organic Chemistry; Veisi, Hojat [Payame Noor University, Songhor, Kermanshah (Iran, Islamic Republic of). Dept. of Chemistry

    2010-07-01

    Easy and rapid preparation of bis-indolyl, tris-indolyl, di(bis-indolyl), tri(bis-indolyl) and tetra(bis-indolyl) methanes from indole with various aldehydes and ketones using poly (N,N'-dichloro-N-ethyl-benzene-1,3-disulfonamide) [PCBS] and N,N,N',N'-tetrachlorobenzene-1,3-disulfonamide [TCBDA] as novel catalysts under various conditions are here described. (author)

  16. Pentatricopeptide repeat proteins in plants.

    Science.gov (United States)

    Barkan, Alice; Small, Ian

    2014-01-01

    Pentatricopeptide repeat (PPR) proteins constitute one of the largest protein families in land plants, with more than 400 members in most species. Over the past decade, much has been learned about the molecular functions of these proteins, where they act in the cell, and what physiological roles they play during plant growth and development. A typical PPR protein is targeted to mitochondria or chloroplasts, binds one or several organellar transcripts, and influences their expression by altering RNA sequence, turnover, processing, or translation. Their combined action has profound effects on organelle biogenesis and function and, consequently, on photosynthesis, respiration, plant development, and environmental responses. Recent breakthroughs in understanding how PPR proteins recognize RNA sequences through modular base-specific contacts will help match proteins to potential binding sites and provide a pathway toward designing synthetic RNA-binding proteins aimed at desired targets.

  17. Two-dimensional quantum repeaters

    Science.gov (United States)

    Wallnöfer, J.; Zwerger, M.; Muschik, C.; Sangouard, N.; Dür, W.

    2016-11-01

    The endeavor to develop quantum networks gave rise to a rapidly developing field with far-reaching applications such as secure communication and the realization of distributed computing tasks. This ultimately calls for the creation of flexible multiuser structures that allow for quantum communication between arbitrary pairs of parties in the network and facilitate also multiuser applications. To address this challenge, we propose a two-dimensional quantum repeater architecture to establish long-distance entanglement shared between multiple communication partners in the presence of channel noise and imperfect local control operations. The scheme is based on the creation of self-similar multiqubit entanglement structures at growing scale, where variants of entanglement swapping and multiparty entanglement purification are combined to create high-fidelity entangled states. We show how such networks can be implemented using trapped ions in cavities.

  18. General benchmarks for quantum repeaters

    CERN Document Server

    Pirandola, Stefano

    2015-01-01

    Using a technique based on quantum teleportation, we simplify the most general adaptive protocols for key distribution, entanglement distillation and quantum communication over a wide class of quantum channels in arbitrary dimension. Thanks to this method, we bound the ultimate rates for secret key generation and quantum communication through single-mode Gaussian channels and several discrete-variable channels. In particular, we derive exact formulas for the two-way assisted capacities of the bosonic quantum-limited amplifier and the dephasing channel in arbitrary dimension, as well as the secret key capacity of the qubit erasure channel. Our results establish the limits of quantum communication with arbitrary systems and set the most general and precise benchmarks for testing quantum repeaters in both discrete- and continuous-variable settings.

  19. Hungarian repeat station survey, 2010

    Directory of Open Access Journals (Sweden)

    Péter Kovács

    2013-03-01

    Full Text Available The last Hungarian repeat station survey was completed between October 2010 and February 2011. Declination, inclination and the total field were observed using one-axial DMI fluxgate magnetometer mounted on Zeiss20A theodolite and GSM 19 Overhauser magnetometer. The magnetic elements of the sites were reduced to the epoch of 2010.5 on the basis of the continuous recordings of Tihany Geophysical Observatory. In stations located far from the reference observatory, the observations were carried out in the morning and afternoon in order to decrease the effect of the distant temporal correction. To further increase the accuracy, on-site dIdD variometer has also been installed near the Aggtelek station, in the Baradla cave, during the survey of the easternmost sites. The paper presents the technical details and the results of our last campaign. The improvement of the accuracy of the temporal reduction by the use of the local variometer is also reported.

  20. Synthesis of bis(indolyl)methanes Catalyzed by Triethylborane

    Science.gov (United States)

    Merinos, J. Pablo García; Ruíz, Heraclio López; López, Yliana; Lima, Susana Rojas

    2015-01-01

    Triethylborane (TEB) was found to be a mild, efficient, and acid catalyst in electrophilic substitution reaction of indoles with aldehydes compounds to afford the corresponding bis(indolyl)methanes. Vibrindole A (5) and bis(indolyl)methanes derivatives 16 and 18 were synthesized using this methodology. Compound 16 is an intermediary in the synthesis of the natural bisindoles arsindoline B (2) and streptindole (6). The structure of vibrindole A (5) was unequivocally confirmed by a single crystal X-ray diffraction analysis. PMID:26120289