Science.gov

Sample records for sampling interval effects

  1. Sampling Theory and Confidence Intervals for Effect Sizes: Using ESCI To Illustrate "Bouncing"; Confidence Intervals.

    ERIC Educational Resources Information Center

    Du, Yunfei

    This paper discusses the impact of sampling error on the construction of confidence intervals around effect sizes. Sampling error affects the location and precision of confidence intervals. Meta-analytic resampling demonstrates that confidence intervals can haphazardly bounce around the true population parameter. Special software with graphical…

  2. Sample Size Calculations for Precise Interval Estimation of the Eta-Squared Effect Size

    ERIC Educational Resources Information Center

    Shieh, Gwowen

    2015-01-01

    Analysis of variance is one of the most frequently used statistical analyses in the behavioral, educational, and social sciences, and special attention has been paid to the selection and use of an appropriate effect size measure of association in analysis of variance. This article presents the sample size procedures for precise interval estimation…

  3. Effects of sampling interval on spatial patterns and statistics of watershed nitrogen concentration

    USGS Publications Warehouse

    Wu, S.-S.D.; Usery, E.L.; Finn, M.P.; Bosch, D.D.

    2009-01-01

    This study investigates how spatial patterns and statistics of a 30 m resolution, model-simulated, watershed nitrogen concentration surface change with sampling intervals from 30 m to 600 m for every 30 m increase for the Little River Watershed (Georgia, USA). The results indicate that the mean, standard deviation, and variogram sills do not have consistent trends with increasing sampling intervals, whereas the variogram ranges remain constant. A sampling interval smaller than or equal to 90 m is necessary to build a representative variogram. The interpolation accuracy, clustering level, and total hot spot areas show decreasing trends approximating a logarithmic function. The trends correspond to the nitrogen variogram and start to level at a sampling interval of 360 m, which is therefore regarded as a critical spatial scale of the Little River Watershed. Copyright ?? 2009 by Bellwether Publishing, Ltd. All right reserved.

  4. Online Doppler Effect Elimination Based on Unequal Time Interval Sampling for Wayside Acoustic Bearing Fault Detecting System.

    PubMed

    Ouyang, Kesai; Lu, Siliang; Zhang, Shangbin; Zhang, Haibin; He, Qingbo; Kong, Fanrang

    2015-08-27

    The railway occupies a fairly important position in transportation due to its high speed and strong transportation capability. As a consequence, it is a key issue to guarantee continuous running and transportation safety of trains. Meanwhile, time consumption of the diagnosis procedure is of extreme importance for the detecting system. However, most of the current adopted techniques in the wayside acoustic defective bearing detector system (ADBD) are offline strategies, which means that the signal is analyzed after the sampling process. This would result in unavoidable time latency. Besides, the acquired acoustic signal would be corrupted by the Doppler effect because of high relative speed between the train and the data acquisition system (DAS). Thus, it is difficult to effectively diagnose the bearing defects immediately. In this paper, a new strategy called online Doppler effect elimination (ODEE) is proposed to remove the Doppler distortion online by the introduced unequal interval sampling scheme. The steps of proposed strategy are as follows: The essential parameters are acquired in advance. Then, the introduced unequal time interval sampling strategy is used to restore the Doppler distortion signal, and the amplitude of the signal is demodulated as well. Thus, the restored Doppler-free signal is obtained online. The proposed ODEE method has been employed in simulation analysis. Ultimately, the ODEE method is implemented in the embedded system for fault diagnosis of the train bearing. The results are in good accordance with the bearing defects, which verifies the good performance of the proposed strategy.

  5. Online Doppler Effect Elimination Based on Unequal Time Interval Sampling for Wayside Acoustic Bearing Fault Detecting System

    PubMed Central

    Ouyang, Kesai; Lu, Siliang; Zhang, Shangbin; Zhang, Haibin; He, Qingbo; Kong, Fanrang

    2015-01-01

    The railway occupies a fairly important position in transportation due to its high speed and strong transportation capability. As a consequence, it is a key issue to guarantee continuous running and transportation safety of trains. Meanwhile, time consumption of the diagnosis procedure is of extreme importance for the detecting system. However, most of the current adopted techniques in the wayside acoustic defective bearing detector system (ADBD) are offline strategies, which means that the signal is analyzed after the sampling process. This would result in unavoidable time latency. Besides, the acquired acoustic signal would be corrupted by the Doppler effect because of high relative speed between the train and the data acquisition system (DAS). Thus, it is difficult to effectively diagnose the bearing defects immediately. In this paper, a new strategy called online Doppler effect elimination (ODEE) is proposed to remove the Doppler distortion online by the introduced unequal interval sampling scheme. The steps of proposed strategy are as follows: The essential parameters are acquired in advance. Then, the introduced unequal time interval sampling strategy is used to restore the Doppler distortion signal, and the amplitude of the signal is demodulated as well. Thus, the restored Doppler-free signal is obtained online. The proposed ODEE method has been employed in simulation analysis. Ultimately, the ODEE method is implemented in the embedded system for fault diagnosis of the train bearing. The results are in good accordance with the bearing defects, which verifies the good performance of the proposed strategy. PMID:26343657

  6. Online Doppler Effect Elimination Based on Unequal Time Interval Sampling for Wayside Acoustic Bearing Fault Detecting System.

    PubMed

    Ouyang, Kesai; Lu, Siliang; Zhang, Shangbin; Zhang, Haibin; He, Qingbo; Kong, Fanrang

    2015-01-01

    The railway occupies a fairly important position in transportation due to its high speed and strong transportation capability. As a consequence, it is a key issue to guarantee continuous running and transportation safety of trains. Meanwhile, time consumption of the diagnosis procedure is of extreme importance for the detecting system. However, most of the current adopted techniques in the wayside acoustic defective bearing detector system (ADBD) are offline strategies, which means that the signal is analyzed after the sampling process. This would result in unavoidable time latency. Besides, the acquired acoustic signal would be corrupted by the Doppler effect because of high relative speed between the train and the data acquisition system (DAS). Thus, it is difficult to effectively diagnose the bearing defects immediately. In this paper, a new strategy called online Doppler effect elimination (ODEE) is proposed to remove the Doppler distortion online by the introduced unequal interval sampling scheme. The steps of proposed strategy are as follows: The essential parameters are acquired in advance. Then, the introduced unequal time interval sampling strategy is used to restore the Doppler distortion signal, and the amplitude of the signal is demodulated as well. Thus, the restored Doppler-free signal is obtained online. The proposed ODEE method has been employed in simulation analysis. Ultimately, the ODEE method is implemented in the embedded system for fault diagnosis of the train bearing. The results are in good accordance with the bearing defects, which verifies the good performance of the proposed strategy. PMID:26343657

  7. Approximate Confidence Intervals for Standardized Effect Sizes in the Two-Independent and Two-Dependent Samples Design

    ERIC Educational Resources Information Center

    Viechtbauer, Wolfgang

    2007-01-01

    Standardized effect sizes and confidence intervals thereof are extremely useful devices for comparing results across different studies using scales with incommensurable units. However, exact confidence intervals for standardized effect sizes can usually be obtained only via iterative estimation procedures. The present article summarizes several…

  8. Accuracy in Parameter Estimation for Targeted Effects in Structural Equation Modeling: Sample Size Planning for Narrow Confidence Intervals

    ERIC Educational Resources Information Center

    Lai, Keke; Kelley, Ken

    2011-01-01

    In addition to evaluating a structural equation model (SEM) as a whole, often the model parameters are of interest and confidence intervals for those parameters are formed. Given a model with a good overall fit, it is entirely possible for the targeted effects of interest to have very wide confidence intervals, thus giving little information about…

  9. A Comparison of Momentary Time Sampling and Partial-Interval Recording for Assessment of Effects of Social Skills Training

    ERIC Educational Resources Information Center

    Radley, Keith C.; O'Handley, Roderick D.; Labrot, Zachary C.

    2015-01-01

    Assessment in social skills training often utilizes procedures such as partial-interval recording (PIR) and momentary time sampling (MTS) to estimate changes in duration in social engagements due to intervention. Although previous research suggests PIR to be more inaccurate than MTS in estimating levels of behavior, treatment analysis decisions…

  10. Effect Sizes, Confidence Intervals, and Confidence Intervals for Effect Sizes

    ERIC Educational Resources Information Center

    Thompson, Bruce

    2007-01-01

    The present article provides a primer on (a) effect sizes, (b) confidence intervals, and (c) confidence intervals for effect sizes. Additionally, various admonitions for reformed statistical practice are presented. For example, a very important implication of the realization that there are dozens of effect size statistics is that "authors must…

  11. Sampling-interval-dependent stability for linear sampled-data systems with non-uniform sampling

    NASA Astrophysics Data System (ADS)

    Shao, Hanyong; Lam, James; Feng, Zhiguang

    2016-09-01

    This paper is concerned with the sampling-interval-dependent stability of linear sampled-data systems with non-uniform sampling. A new Lyapunov-like functional is constructed to derive sampling-interval-dependent stability results. The Lyapunov-like functional has three features. First, it depends on time explicitly. Second, it may be discontinuous at the sampling instants. Third, it is not required to be positive definite between sampling instants. Moreover, the new Lyapunov-like functional can make use of the information fully of the sampled-data system, including that of both ends of the sampling interval. By making a new proposition for the Lyapunov-like functional, a sampling-interval-dependent stability criterion with reduced conservatism is derived. The new sampling-interval-dependent stability criterion is further extended to linear sampled-data systems with polytopic uncertainties. Finally, examples are given to illustrate the reduced conservatism of the stability criteria.

  12. Off-axis angular spectrum method with variable sampling interval

    NASA Astrophysics Data System (ADS)

    Kim, Yong-Hae; Byun, Chun-Won; Oh, Himchan; Pi, Jae-Eun; Choi, Ji-Hun; Kim, Gi Heon; Lee, Myung-Lae; Ryu, Hojun; Hwang, Chi-Sun

    2015-08-01

    We proposed a novel off-axis angular spectrum method (ASM) for simulating free space wave propagation with a large shifted destination plane. The off-axis numerical simulation took wave propagation between a parallel source and a destination plane, but a destination plane was shifted from a source plane. The shifted angular spectrum method was proposed for diffraction simulation with a shifted destination plane and satisfied the Nyquist condition for sampling by limiting a bandwidth of a propagation field to avoid an aliasing error due to under sampling. However, the effective sampling number of the shifted ASM decreased when the shifted distance of the destination plane was large which caused a numerical error in the diffraction simulation. To compensate for the decrease of an effective sampling number for the large shifted destination plane, we used a variable sampling interval in a Fourier space to maintain the same effective sampling number independent of the shifted distance of the destination plane. As a result, our proposed off-axis ASM with a variable sampling interval can produce simulation results with high accuracy for nearly every shifted distance of a destination plane when an off-axis angle is less than 75°. We compared the performances of the off-axis ASM using the Chirp Z transform and non-uniform FFT for implementing a variable spatial frequency in a Fourier space.

  13. Interval sampling methods and measurement error: a computer simulation.

    PubMed

    Wirth, Oliver; Slaven, James; Taylor, Matthew A

    2014-01-01

    A simulation study was conducted to provide a more thorough account of measurement error associated with interval sampling methods. A computer program simulated the application of momentary time sampling, partial-interval recording, and whole-interval recording methods on target events randomly distributed across an observation period. The simulation yielded measures of error for multiple combinations of observation period, interval duration, event duration, and cumulative event duration. The simulations were conducted up to 100 times to yield measures of error variability. Although the present simulation confirmed some previously reported characteristics of interval sampling methods, it also revealed many new findings that pertain to each method's inherent strengths and weaknesses. The analysis and resulting error tables can help guide the selection of the most appropriate sampling method for observation-based behavioral assessments.

  14. Comparing interval estimates for small sample ordinal CFA models.

    PubMed

    Natesan, Prathiba

    2015-01-01

    Robust maximum likelihood (RML) and asymptotically generalized least squares (AGLS) methods have been recommended for fitting ordinal structural equation models. Studies show that some of these methods underestimate standard errors. However, these studies have not investigated the coverage and bias of interval estimates. An estimate with a reasonable standard error could still be severely biased. This can only be known by systematically investigating the interval estimates. The present study compares Bayesian, RML, and AGLS interval estimates of factor correlations in ordinal confirmatory factor analysis models (CFA) for small sample data. Six sample sizes, 3 factor correlations, and 2 factor score distributions (multivariate normal and multivariate mildly skewed) were studied. Two Bayesian prior specifications, informative and relatively less informative were studied. Undercoverage of confidence intervals and underestimation of standard errors was common in non-Bayesian methods. Underestimated standard errors may lead to inflated Type-I error rates. Non-Bayesian intervals were more positive biased than negatively biased, that is, most intervals that did not contain the true value were greater than the true value. Some non-Bayesian methods had non-converging and inadmissible solutions for small samples and non-normal data. Bayesian empirical standard error estimates for informative and relatively less informative priors were closer to the average standard errors of the estimates. The coverage of Bayesian credibility intervals was closer to what was expected with overcoverage in a few cases. Although some Bayesian credibility intervals were wider, they reflected the nature of statistical uncertainty that comes with the data (e.g., small sample). Bayesian point estimates were also more accurate than non-Bayesian estimates. The results illustrate the importance of analyzing coverage and bias of interval estimates, and how ignoring interval estimates can be misleading

  15. Sampling Theorem in Terms of the Bandwidth and Sampling Interval

    NASA Technical Reports Server (NTRS)

    Dean, Bruce H.

    2011-01-01

    An approach has been developed for interpolating non-uniformly sampled data, with applications in signal and image reconstruction. This innovation generalizes the Whittaker-Shannon sampling theorem by emphasizing two assumptions explicitly (definition of a band-limited function and construction by periodic extension). The Whittaker- Shannon sampling theorem is thus expressed in terms of two fundamental length scales that are derived from these assumptions. The result is more general than what is usually reported, and contains the Whittaker- Shannon form as a special case corresponding to Nyquist-sampled data. The approach also shows that the preferred basis set for interpolation is found by varying the frequency component of the basis functions in an optimal way.

  16. Effect of initial seed and number of samples on simple-random and Latin-Hypercube Monte Carlo probabilities (confidence interval considerations)

    SciTech Connect

    ROMERO,VICENTE J.

    2000-05-04

    In order to devise an algorithm for autonomously terminating Monte Carlo sampling when sufficiently small and reliable confidence intervals (CI) are achieved on calculated probabilities, the behavior of CI estimators must be characterized. This knowledge is also required in comparing the accuracy of other probability estimation techniques to Monte Carlo results. Based on 100 trials in a hypothesis test, estimated 95% CI from classical approximate CI theory are empirically examined to determine if they behave as true 95% CI over spectrums of probabilities (population proportions) ranging from 0.001 to 0.99 in a test problem. Tests are conducted for population sizes of 500 and 10,000 samples where applicable. Significant differences between true and estimated 95% CI are found to occur at probabilities between 0.1 and 0.9, such that estimated 95% CI can be rejected as not being true 95% CI at less than a 40% chance of incorrect rejection. With regard to Latin Hypercube sampling (LHS), though no general theory has been verified for accurately estimating LHS CI, recent numerical experiments on the test problem have found LHS to be conservatively over an order of magnitude more efficient than SRS for similar sized CI on probabilities ranging between 0.25 and 0.75. The efficiency advantage of LHS vanishes, however, as the probability extremes of 0 and 1 are approached.

  17. Sample Size for the "Z" Test and Its Confidence Interval

    ERIC Educational Resources Information Center

    Liu, Xiaofeng Steven

    2012-01-01

    The statistical power of a significance test is closely related to the length of the confidence interval (i.e. estimate precision). In the case of a "Z" test, the length of the confidence interval can be expressed as a function of the statistical power. (Contains 1 figure and 1 table.)

  18. ON-LINE TOOLS FOR PROPER VERTICAL POSITIONING OF VERTICAL SAMPLING INTERVALS DURING SITE ASSESSMENT

    EPA Science Inventory

    This presentation presents on-line tools for proper vertical positioning of vertical sampling intervals during site assessment. Proper vertical sample interval selection is critical for generate data on the vertical distribution of contamination. Without vertical delineation, th...

  19. Confidence Interval Coverage for Cohen's Effect Size Statistic

    ERIC Educational Resources Information Center

    Algina, James; Keselman, H. J.; Penfield, Randall D.

    2006-01-01

    Kelley compared three methods for setting a confidence interval (CI) around Cohen's standardized mean difference statistic: the noncentral-"t"-based, percentile (PERC) bootstrap, and biased-corrected and accelerated (BCA) bootstrap methods under three conditions of nonnormality, eight cases of sample size, and six cases of population effect size…

  20. Two-year observations of fine carbonaceous particles in variable sampling intervals

    NASA Astrophysics Data System (ADS)

    Yang, Fumo; Huang, Lin; Sharma, Sangeeta; Brook, Jeffrey R.; Zhang, Wendy; Li, Shao-Meng; Tan, Jihua

    2011-05-01

    Daily to weekly integrated PM 2.5 samples were collected consecutively from August 2005 through November 2007 at Egbert, a rural site in southern Ontario with two collocated samplers to characterize temporal variations of organic and elemental carbon (OC and EC) concentrations and to review the effects of different sampling intervals on their respective concentrations. OC and EC concentrations from both samplers had reasonable agreements for the samples with identical sampling intervals, whereas for the samples with different sampling intervals, they did not coincide. Considering sampling artifacts, analytical challenges and highly varied daily concentrations, it is suggested and would be advantageous to adopt the weekly integrated sampling strategy other than 24-h sampling on selected days for long-term trend studies on ambient carbonaceous PM. Both OC and EC concentrations varied seasonally by factors of 2.4 and their concentrations in warm seasons (May-October) were higher than those in cold seasons (November-April). Greater fluctuations were also found in warm seasons during the study period. Weekly concentrations of carbonaceous species at Egbert and urban Toronto show similar temporal variations and small urban excess during the one-year parallel sampling period, indicating a relatively large regional contribution from transport instead of local emissions to the paired urban-rural sites. The continental background level of total carbon mass (TCM) in PM 2.5 in southern Ontario, constrained by surface air mass directions and back trajectories, was estimated to be 0.5 μg m -3. It is likely that the elevated OC level during the warm season in 2007 compared with those in 2006 was due to more smog days in 2007.

  1. Introduction to Sample Size Choice for Confidence Intervals Based on "t" Statistics

    ERIC Educational Resources Information Center

    Liu, Xiaofeng Steven; Loudermilk, Brandon; Simpson, Thomas

    2014-01-01

    Sample size can be chosen to achieve a specified width in a confidence interval. The probability of obtaining a narrow width given that the confidence interval includes the population parameter is defined as the power of the confidence interval, a concept unfamiliar to many practitioners. This article shows how to utilize the Statistical Analysis…

  2. Exact intervals and tests for median when one sample value possibly an outliner

    NASA Technical Reports Server (NTRS)

    Keller, G. J.; Walsh, J. E.

    1973-01-01

    Available are independent observations (continuous data) that are believed to be a random sample. Desired are distribution-free confidence intervals and significance tests for the population median. However, there is the possibility that either the smallest or the largest observation is an outlier. Then, use of a procedure for rejection of an outlying observation might seem appropriate. Such a procedure would consider that two alternative situations are possible and would select one of them. Either (1) the n observations are truly a random sample, or (2) an outlier exists and its removal leaves a random sample of size n-1. For either situation, confidence intervals and tests are desired for the median of the population yielding the random sample. Unfortunately, satisfactory rejection procedures of a distribution-free nature do not seem to be available. Moreover, all rejection procedures impose undesirable conditional effects on the observations, and also, can select the wrong one of the two above situations. It is found that two-sided intervals and tests based on two symmetrically located order statistics (not the largest and smallest) of the n observations have this property.

  3. Calculating Confidence Intervals for Effect Sizes Using Noncentral Distributions.

    ERIC Educational Resources Information Center

    Norris, Deborah

    This paper provides a brief review of the concepts of confidence intervals, effect sizes, and central and noncentral distributions. The use of confidence intervals around effect sizes is discussed. A demonstration of the Exploratory Software for Confidence Intervals (G. Cuming and S. Finch, 2001; ESCI) is given to illustrate effect size confidence…

  4. Notes on interval estimation of the gamma correlation under stratified random sampling.

    PubMed

    Lui, Kung-Jong; Chang, Kuang-Chao

    2012-07-01

    We have developed four asymptotic interval estimators in closed forms for the gamma correlation under stratified random sampling, including the confidence interval based on the most commonly used weighted-least-squares (WLS) approach (CIWLS), the confidence interval calculated from the Mantel-Haenszel (MH) type estimator with the Fisher-type transformation (CIMHT), the confidence interval using the fundamental idea of Fieller's Theorem (CIFT) and the confidence interval derived from a monotonic function of the WLS estimator of Agresti's α with the logarithmic transformation (MWLSLR). To evaluate the finite-sample performance of these four interval estimators and note the possible loss of accuracy in application of both Wald's confidence interval and MWLSLR using pooled data without accounting for stratification, we employ Monte Carlo simulation. We use the data taken from a general social survey studying the association between the income level and job satisfaction with strata formed by genders in black Americans published elsewhere to illustrate the practical use of these interval estimators. PMID:22622622

  5. Notes on interval estimation of the generalized odds ratio under stratified random sampling.

    PubMed

    Lui, Kung-Jong; Chang, Kuang-Chao

    2013-05-01

    It is not rare to encounter the patient response on the ordinal scale in a randomized clinical trial (RCT). Under the assumption that the generalized odds ratio (GOR) is homogeneous across strata, we consider four asymptotic interval estimators for the GOR under stratified random sampling. These include the interval estimator using the weighted-least-squares (WLS) approach with the logarithmic transformation (WLSL), the interval estimator using the Mantel-Haenszel (MH) type of estimator with the logarithmic transformation (MHL), the interval estimator using Fieller's theorem with the MH weights (FTMH) and the interval estimator using Fieller's theorem with the WLS weights (FTWLS). We employ Monte Carlo simulation to evaluate the performance of these interval estimators by calculating the coverage probability and the average length. To study the bias of these interval estimators, we also calculate and compare the noncoverage probabilities in the two tails of the resulting confidence intervals. We find that WLSL and MHL can generally perform well, while FTMH and FTWLS can lose either precision or accuracy. We further find that MHL is likely the least biased. Finally, we use the data taken from a study of smoking status and breathing test among workers in certain industrial plants in Houston, Texas, during 1974 to 1975 to illustrate the use of these interval estimators.

  6. The effect of instrumental timbre on interval discrimination.

    PubMed

    Zarate, Jean Mary; Ritson, Caroline R; Poeppel, David

    2013-01-01

    We tested non-musicians and musicians in an auditory psychophysical experiment to assess the effects of timbre manipulation on pitch-interval discrimination. Both groups were asked to indicate the larger of two presented intervals, comprised of four sequentially presented pitches; the second or fourth stimulus within a trial was either a sinusoidal (or "pure"), flute, piano, or synthetic voice tone, while the remaining three stimuli were all pure tones. The interval-discrimination tasks were administered parametrically to assess performance across varying pitch distances between intervals ("interval-differences"). Irrespective of timbre, musicians displayed a steady improvement across interval-differences, while non-musicians only demonstrated enhanced interval discrimination at an interval-difference of 100 cents (one semitone in Western music). Surprisingly, the best discrimination performance across both groups was observed with pure-tone intervals, followed by intervals containing a piano tone. More specifically, we observed that: 1) timbre changes within a trial affect interval discrimination; and 2) the broad spectral characteristics of an instrumental timbre may influence perceived pitch or interval magnitude and make interval discrimination more difficult. PMID:24066179

  7. The Effect of Instrumental Timbre on Interval Discrimination

    PubMed Central

    Zarate, Jean Mary; Ritson, Caroline R.; Poeppel, David

    2013-01-01

    We tested non-musicians and musicians in an auditory psychophysical experiment to assess the effects of timbre manipulation on pitch-interval discrimination. Both groups were asked to indicate the larger of two presented intervals, comprised of four sequentially presented pitches; the second or fourth stimulus within a trial was either a sinusoidal (or “pure”), flute, piano, or synthetic voice tone, while the remaining three stimuli were all pure tones. The interval-discrimination tasks were administered parametrically to assess performance across varying pitch distances between intervals (“interval-differences”). Irrespective of timbre, musicians displayed a steady improvement across interval-differences, while non-musicians only demonstrated enhanced interval discrimination at an interval-difference of 100 cents (one semitone in Western music). Surprisingly, the best discrimination performance across both groups was observed with pure-tone intervals, followed by intervals containing a piano tone. More specifically, we observed that: 1) timbre changes within a trial affect interval discrimination; and 2) the broad spectral characteristics of an instrumental timbre may influence perceived pitch or interval magnitude and make interval discrimination more difficult. PMID:24066179

  8. Delay-dependent resilient-robust stabilisation of uncertain networked control systems with variable sampling intervals

    NASA Astrophysics Data System (ADS)

    Yang, Feisheng; Zhang, Huaguang; Liu, Zhenwei; Li, Ranran

    2014-03-01

    This work is concerned with the robust resilient control problem for uncertain networked control systems (NCSs) with variable sampling intervals, variant-induced delays and possible data dropouts, which is seldom considered in current literature. It is mainly based on the continuous time-varying-delay system approach. Followed by the nominal case, delay-dependent resilient robust stabilising conditions for the closed-loop NCS against controller gain variations are derived by employing a novel Lyapunov-Krasovskii functional which makes good use of the information of both lower and upper bounds on the varying input delay, and the upper bound on the variable sampling interval as well. A feasible solution of the obtained criterion formulated as linear matrix inequalities can be gotten. A tighter bounding technique is presented for acquiring the time derivative of the functional so as to utilise many more useful elements, meanwhile neither slack variable nor correlated augmented item is introduced to reduce overall computational burden. Two examples are given to show the effectiveness of the proposed method.

  9. Kernels for longitudinal data with variable sequence length and sampling intervals.

    PubMed

    Lu, Zhengdong; Leen, Todd K; Kaye, Jeffrey

    2011-09-01

    We develop several kernel methods for classification of longitudinal data and apply them to detect cognitive decline in the elderly. We first develop mixed-effects models, a type of hierarchical empirical Bayes generative models, for the time series. After demonstrating their utility in likelihood ratio classifiers (and the improvement over standard regression models for such classifiers), we develop novel Fisher kernels based on mixture of mixed-effects models and use them in support vector machine classifiers. The hierarchical generative model allows us to handle variations in sequence length and sampling interval gracefully. We also give nonparametric kernels not based on generative models, but rather on the reproducing kernel Hilbert space. We apply the methods to detecting cognitive decline from longitudinal clinical data on motor and neuropsychological tests. The likelihood ratio classifiers based on the neuropsychological tests perform better than than classifiers based on the motor behavior. Discriminant classifiers performed better than likelihood ratio classifiers for the motor behavior tests.

  10. Multiport well design for sampling of ground water at closely spaced vertical intervals

    USGS Publications Warehouse

    Delin, G.N.; Landon, M.K.

    1996-01-01

    Detailed vertical sampling is useful in aquifers where vertical mixing is limited and steep vertical gradients in chemical concentrations are expected. Samples can be collected at closely spaced vertical intervals from nested wells with short screened intervals. However, this approach may not be appropriate in all situations. An easy-to-construct and easy-to-install multiport sampling well to collect ground-water samples from closely spaced vertical intervals was developed and tested. The multiport sampling well was designed to sample ground water from surficial sand-and-gravel aquifers. The device consists of multiple stainless-steel tubes within a polyvinyl chloride (PVC) protective casing. The tubes protrude through the wall of the PVC casing at the desired sampling depths. A peristaltic pump is used to collect ground-water samples from the sampling ports. The difference in hydraulic head between any two sampling ports can be measured with a vacuum pump and a modified manometer. The usefulness and versatility of this multiport well design was demonstrated at an agricultural research site near Princeton, Minnesota where sampling ports were installed to a maximum depth of about 12 m below land surface. Tracer experiments were conducted using potassium bromide to document the degree to which short-circuiting occurred between sampling ports. Samples were successfully collected for analysis of major cations and anions, nutrients, selected herbicides, isotopes, dissolved gases, and chlorofluorcarbon concentrations.

  11. Multiport well design for sampling of ground water at closely spaced vertical intervals

    SciTech Connect

    Delin, G.N.; Landon, M.K.

    1996-11-01

    Detailed vertical sampling is useful in aquifers where vertical mixing is limited and steep vertical gradients in chemical concentrations are expected. Samples can be collected at closely spaced vertical intervals from nested wells with short screened intervals. However, this approach may not be appropriate in all situations. An easy-to-construct and easy-to-install multiport sampling well to collect ground-water samples from closely spaced vertical intervals was developed and tested. The multiport sampling well was designed to sample ground water from surficial sand-and-gravel aquifers. The device consists of multiple stainless-steel tubes within a polyvinyl chloride (PVC) protective casing. The tubes protrude through the wall of the PVC casing at the desired sampling depths. A peristaltic pump is used to collect ground-water samples form the sampling ports. The difference in hydraulic head between any two sampling ports can be measured with a vacuum pump and a modified manometer. The usefulness and versatility of this multiport well design was demonstrated at an agricultural research site near Princeton, Minnesota where sampling ports were installed to a maximum depth of about 12 m below land surface. Trace experiments were conducted using potassium bromide to document the degree to which short-circuiting occurred between sampling ports. Samples were successfully collected for analysis of major cations and anions, nutrients, selected herbicides, isotopes, dissolved gases, and chlorofluorocarbon concentrations.

  12. Sample Size for Confidence Interval of Covariate-Adjusted Mean Difference

    ERIC Educational Resources Information Center

    Liu, Xiaofeng Steven

    2010-01-01

    This article provides a way to determine adequate sample size for the confidence interval of covariate-adjusted mean difference in randomized experiments. The standard error of adjusted mean difference depends on covariate variance and balance, which are two unknown quantities at the stage of planning sample size. If covariate observations are…

  13. The Naive Intuitive Statistician: A Naive Sampling Model of Intuitive Confidence Intervals

    ERIC Educational Resources Information Center

    Juslin, Peter; Winman, Anders; Hansson, Patrik

    2007-01-01

    The perspective of the naive intuitive statistician is outlined and applied to explain overconfidence when people produce intuitive confidence intervals and why this format leads to more overconfidence than other formally equivalent formats. The naive sampling model implies that people accurately describe the sample information they have but are…

  14. Interval Estimation of Standardized Mean Differences in Paired-Samples Designs

    ERIC Educational Resources Information Center

    Bonett, Douglas G.

    2015-01-01

    Paired-samples designs are used frequently in educational and behavioral research. In applications where the response variable is quantitative, researchers are encouraged to supplement the results of a paired-samples t-test with a confidence interval (CI) for a mean difference or a standardized mean difference. Six CIs for standardized mean…

  15. The influence of sampling interval on the accuracy of trail impact assessment

    USGS Publications Warehouse

    Leung, Y.-F.; Marion, J.L.

    1999-01-01

    Trail impact assessment and monitoring (IA&M) programs have been growing in importance and application in recreation resource management at protected areas. Census-based and sampling-based approaches have been developed in such programs, with systematic point sampling being the most common survey design. This paper examines the influence of sampling interval on the accuracy of estimates for selected trail impact problems. A complete census of four impact types on 70 trails in Great Smoky Mountains National Park was utilized as the base data set for the analyses. The census data were resampled at increasing intervals to create a series of simulated point data sets. Estimates of frequency of occurrence and lineal extent for the four impact types were compared with the census data set. The responses of accuracy loss on lineal extent estimates to increasing sampling intervals varied across different impact types, while the responses on frequency of occurrence estimates were consistent, approximating an inverse asymptotic curve. These findings suggest that systematic point sampling may be an appropriate method for estimating the lineal extent but not the frequency of trail impacts. Sample intervals of less than 100 m appear to yield an excellent level of accuracy for the four impact types evaluated. Multiple regression analysis results suggest that appropriate sampling intervals are more likely to be determined by the type of impact in question rather than the length of trail. The census-based trail survey and the resampling-simulation method developed in this study can be a valuable first step in establishing long-term trail IA&M programs, in which an optimal sampling interval range with acceptable accuracy is determined before investing efforts in data collection.

  16. A comparison of momentary time sampling and partial-interval recording for evaluating functional relations.

    PubMed

    Meany-Daboul, Maeve G; Roscoe, Eileen M; Bourret, Jason C; Ahearn, William H

    2007-01-01

    In the current study, momentary time sampling (MTS) and partial-interval recording (PIR) were compared to continuous-duration recording of stereotypy and to the frequency of self-injury during a treatment analysis to determine whether the recording method affected data interpretation. Five previously conducted treatment analysis data sets were analyzed by creating separate graphic displays for each measurement method (duration or frequency, MTS, and PIR). An expert panel interview and structured criterion visual inspection were used to evaluate treatment effects across measurement methods. Results showed that treatment analysis interpretations based on both discontinuous recording methods often matched those based on frequency or duration recording; however, interpretations based on MTS were slightly more likely to match those based on duration and those based on PIR were slightly more likely to match those based on frequency.

  17. Phylogenetic effective sample size.

    PubMed

    Bartoszek, Krzysztof

    2016-10-21

    In this paper I address the question-how large is a phylogenetic sample? I propose a definition of a phylogenetic effective sample size for Brownian motion and Ornstein-Uhlenbeck processes-the regression effective sample size. I discuss how mutual information can be used to define an effective sample size in the non-normal process case and compare these two definitions to an already present concept of effective sample size (the mean effective sample size). Through a simulation study I find that the AICc is robust if one corrects for the number of species or effective number of species. Lastly I discuss how the concept of the phylogenetic effective sample size can be useful for biodiversity quantification, identification of interesting clades and deciding on the importance of phylogenetic correlations. PMID:27343033

  18. Examination of histological samples from submerged carrion to aid in the determination of postmortem submersion interval.

    PubMed

    Humphreys, Michael Keith; Panacek, Edward; Green, William; Albers, Elizabeth

    2013-03-01

    The use of histology in the as a tool for estimating postmortem intervals has rarely been explored but it has the potential for offering medical examiners an additional means for estimating the postmortem submersion interval (PMSI) during a death investigation. This study used perinatal piglets as human analogs which were submerged in freshwater for various time intervals. Each piglet was extracted from the water and underwent a necropsy examination during which histological samples were collected. The samples revealed that the necrotic tissue decomposed relatively predictably over time and that this decompositional progression may have the potential to be used via a scoring system to determine or aid in determining the PMSI. This method for calculating PMSI allows for normalization between piglets of various mass and body types. It also prevents any contamination of the remains via algae growth and animal activity that may exacerbate and possibly exaggerate PMSI calculation.

  19. Reporting Confidence Intervals and Effect Sizes: Collecting the Evidence

    ERIC Educational Resources Information Center

    Zientek, Linda Reichwein; Ozel, Z. Ebrar Yetkiner; Ozel, Serkan; Allen, Jeff

    2012-01-01

    Confidence intervals (CIs) and effect sizes are essential to encourage meta-analytic thinking and to accumulate research findings. CIs provide a range of plausible values for population parameters with a degree of confidence that the parameter is in that particular interval. CIs also give information about how precise the estimates are. Comparison…

  20. Confidence Intervals for Effect Sizes: Applying Bootstrap Resampling

    ERIC Educational Resources Information Center

    Banjanovic, Erin S.; Osborne, Jason W.

    2016-01-01

    Confidence intervals for effect sizes (CIES) provide readers with an estimate of the strength of a reported statistic as well as the relative precision of the point estimate. These statistics offer more information and context than null hypothesis statistic testing. Although confidence intervals have been recommended by scholars for many years,…

  1. A Comparison of Momentary Time Sampling and Partial-Interval Recording for Evaluating Functional Relations

    ERIC Educational Resources Information Center

    Meany-Daboul, Maeve G.; Roscoe, Eileen M.; Bourret, Jason C.; Ahearn, William H.

    2007-01-01

    In the current study, momentary time sampling (MTS) and partial-interval recording (PIR) were compared to continuous-duration recording of stereotypy and to the frequency of self-injury during a treatment analysis to determine whether the recording method affected data interpretation. Five previously conducted treatment analysis data sets were…

  2. Sample Size Planning for the Standardized Mean Difference: Accuracy in Parameter Estimation via Narrow Confidence Intervals

    ERIC Educational Resources Information Center

    Kelley, Ken; Rausch, Joseph R.

    2006-01-01

    Methods for planning sample size (SS) for the standardized mean difference so that a narrow confidence interval (CI) can be obtained via the accuracy in parameter estimation (AIPE) approach are developed. One method plans SS so that the expected width of the CI is sufficiently narrow. A modification adjusts the SS so that the obtained CI is no…

  3. A Variable Sampling Interval Synthetic Xbar Chart for the Process Mean.

    PubMed

    Lee, Lei Yong; Khoo, Michael Boon Chong; Teh, Sin Yin; Lee, Ming Ha

    2015-01-01

    The usual practice of using a control chart to monitor a process is to take samples from the process with fixed sampling interval (FSI). In this paper, a synthetic X control chart with the variable sampling interval (VSI) feature is proposed for monitoring changes in the process mean. The VSI synthetic X chart integrates the VSI X chart and the VSI conforming run length (CRL) chart. The proposed VSI synthetic X chart is evaluated using the average time to signal (ATS) criterion. The optimal charting parameters of the proposed chart are obtained by minimizing the out-of-control ATS for a desired shift. Comparisons between the VSI synthetic X chart and the existing X, synthetic X, VSI X and EWMA X charts, in terms of ATS, are made. The ATS results show that the VSI synthetic X chart outperforms the other X type charts for detecting moderate and large shifts. An illustrative example is also presented to explain the application of the VSI synthetic X chart.

  4. A Variable Sampling Interval Synthetic Xbar Chart for the Process Mean

    PubMed Central

    Lee, Lei Yong; Khoo, Michael Boon Chong; Teh, Sin Yin; Lee, Ming Ha

    2015-01-01

    The usual practice of using a control chart to monitor a process is to take samples from the process with fixed sampling interval (FSI). In this paper, a synthetic X¯ control chart with the variable sampling interval (VSI) feature is proposed for monitoring changes in the process mean. The VSI synthetic X¯ chart integrates the VSI X¯ chart and the VSI conforming run length (CRL) chart. The proposed VSI synthetic X¯ chart is evaluated using the average time to signal (ATS) criterion. The optimal charting parameters of the proposed chart are obtained by minimizing the out-of-control ATS for a desired shift. Comparisons between the VSI synthetic X¯ chart and the existing X¯, synthetic X¯, VSI X¯ and EWMA X¯ charts, in terms of ATS, are made. The ATS results show that the VSI synthetic X¯ chart outperforms the other X¯ type charts for detecting moderate and large shifts. An illustrative example is also presented to explain the application of the VSI synthetic X¯ chart. PMID:25951141

  5. Finite sample pointwise confidence intervals for a survival distribution with right-censored data.

    PubMed

    Fay, Michael P; Brittain, Erica H

    2016-07-20

    We review and develop pointwise confidence intervals for a survival distribution with right-censored data for small samples, assuming only independence of censoring and survival. When there is no censoring, at each fixed time point, the problem reduces to making inferences about a binomial parameter. In this case, the recently developed beta product confidence procedure (BPCP) gives the standard exact central binomial confidence intervals of Clopper and Pearson. Additionally, the BPCP has been shown to be exact (gives guaranteed coverage at the nominal level) for progressive type II censoring and has been shown by simulation to be exact for general independent right censoring. In this paper, we modify the BPCP to create a 'mid-p' version, which reduces to the mid-p confidence interval for a binomial parameter when there is no censoring. We perform extensive simulations on both the standard and mid-p BPCP using a method of moments implementation that enforces monotonicity over time. All simulated scenarios suggest that the standard BPCP is exact. The mid-p BPCP, like other mid-p confidence intervals, has simulated coverage closer to the nominal level but may not be exact for all survival times, especially in very low censoring scenarios. In contrast, the two asymptotically-based approximations have lower than nominal coverage in many scenarios. This poor coverage is due to the extreme inflation of the lower error rates, although the upper limits are very conservative. Both the standard and the mid-p BPCP methods are available in our bpcp R package. Published 2016. This article is US Government work and is in the public domain in the USA. PMID:26891706

  6. The different effects of high intensity interval training and moderate intensity interval training for weightlessness countermeasures

    NASA Astrophysics Data System (ADS)

    Wang, Lin-Jie; Cheng, Tan; Zhi-Li, Li; Hui-juan, Wang; Wen-juan, Chen; Jianfeng, Zhang; Desheng, Wang; Dongbin, Niu; Qi, Zhao; Chengjia, Yang; Yanqing, Wang

    High intensity interval training (HIIT) has been demonstrated to improve performance in a relatively short training period. But the difference between high intensity interval training and moderate intensity interval training (MIIT) in simulated weightlessness still has not been well studied. This study sought to characterize the difference between 6 weeks high intensity interval training and moderate intensity interval training under reduced weight (RW) gait training device and zero-gravity locomotion system (ZLS). Twenty-three subjects (14M/4F, 32.5±4.5 years) volunteered to participate. They were divided into three groups, that were MITT (alternating 2 min at 40% VO _{2} peak and 2 min at 60% VO _{2} peak for 30min, five days per week) RW group (n=8), HITT (alternating 2 min at 40% VO _{2} peak and 2 min at 90% VO _{2} peak for 30min, three days per week) RW group (n=8) and HITT ZLS group (n=7). The Z-axis load used in RW group was 80% body weight (BW) and in ZLS was 100% BW. Cardiopulmonary function was measured before, after 4-week training and after 6-week training. Isokinetic knee extension-flexion test at 60(°) deg/s and 180(°) deg/s were performed before and after the 6-week training, and isometric knee extension-flexion test at 180(°) deg/s was also examined at the same time. It was found that the VO _{2} peaks, metabolic equivalent (MET), Speedmax and respiratory exchange ratio (RER) were significantly increased after 4 and 6-week training in all three groups and no significant group difference were detected. The peak torque at 60(°) deg/s for right knee flexion were significantly increased after 6 week-training in all three groups, and only in HITT RW group the total power at 60(°) deg/s for right knee flexion enhanced. The total power and average power at 60(°) deg/s for right knee extension decreased significantly after 6-week training in all three groups. The peak torque at 60(°) deg/s for right knee extension in MIIT RW group was

  7. The use of latin hypercube sampling for the efficient estimation of confidence intervals

    SciTech Connect

    Grabaskas, D.; Denning, R.; Aldemir, T.; Nakayama, M. K.

    2012-07-01

    Latin hypercube sampling (LHS) has long been used as a way of assuring adequate sampling of the tails of distributions in a Monte Carlo analysis and provided the framework for the uncertainty analysis performed in the NUREG-1150 risk assessment. However, this technique has not often been used in the performance of regulatory analyses due to the inability to establish confidence levels on the quantiles of the output distribution. Recent work has demonstrated a method that makes this possible. This method is compared to the procedure of crude Monte Carlo using order statistics, which is currently used to establish confidence levels. The results of several statistical examples demonstrate that the LHS confidence interval method can provide a more accurate and precise solution, but issues remain when applying the technique generally. (authors)

  8. Effects of prefeeding, intercomponent-interval food, and extinction on temporal discrimination and pacemaker rate.

    PubMed

    Ward, Ryan D; Odum, Amy L

    2006-02-28

    This experiment investigated the effects of nonpharmacological disruption on temporal discrimination. Pigeons responded on a multiple schedule composed of fixed interval, color-matching, and temporal-discrimination components. The effects of three different disruptors (prefeeding, intercomponent-interval food, and extinction) were assessed. All disruptors decreased response rates during the fixed interval. Prefeeding and intercomponent-interval food had unsystematic effects on response patterning during the fixed interval, whereas extinction increased the relative response rate in the initial portions of the fixed interval. Accuracy of color matching was decreased by prefeeding and was not systematically affected by intercomponent-interval food and extinction. In the temporal-discrimination component, all disruptors flattened the psychophysical functions relating proportion long responses to sample duration. This result indicates a general disruption of temporal discrimination. In addition, parameter estimates derived from the behavioral theory of timing indicated all disruptors decreased pacemaker rate, a result consistent with the predictions of the theory. These results highlight the similarities between disruption of temporal discrimination by pharmacological and nonpharmacological manipulations.

  9. Decision-aided sampling frequency offset compensation for reduced-guard-interval coherent optical OFDM systems.

    PubMed

    Wang, Wei; Zhuge, Qunbi; Morsy-Osman, Mohamed; Gao, Yuliang; Xu, Xian; Chagnon, Mathieu; Qiu, Meng; Hoang, Minh Thang; Zhang, Fangyuan; Li, Rui; Plant, David V

    2014-11-01

    We propose a decision-aided algorithm to compensate the sampling frequency offset (SFO) between the transmitter and receiver for reduced-guard-interval (RGI) coherent optical (CO) OFDM systems. In this paper, we first derive the cyclic prefix (CP) requirement for preventing OFDM symbols from SFO induced inter-symbol interference (ISI). Then we propose a new decision-aided SFO compensation (DA-SFOC) algorithm, which shows a high SFO tolerance and reduces the CP requirement. The performance of DA-SFOC is numerically investigated for various situations. Finally, the proposed algorithm is verified in a single channel 28 Gbaud polarization division multiplexing (PDM) RGI CO-OFDM experiment with QPSK, 8 QAM and 16 QAM modulation formats, respectively. Both numerical and experimental results show that the proposed DA-SFOC method is highly robust against the standard SFO in optical fiber transmission. PMID:25401902

  10. Confidence intervals for two sample means: Calculation, interpretation, and a few simple rules

    PubMed Central

    Pfister, Roland; Janczyk, Markus

    2013-01-01

    Valued by statisticians, enforced by editors, and confused by many authors, standard errors (SEs) and confidence intervals (CIs) remain a controversial issue in the psychological literature. This is especially true for the proper use of CIs for within-subjects designs, even though several recent publications elaborated on possible solutions for this case. The present paper presents a short and straightforward introduction to the basic principles of CI construction, in an attempt to encourage students and researchers in cognitive psychology to use CIs in their reports and presentations. Focusing on a simple but prevalent case of statistical inference, the comparison of two sample means, we describe possible CIs for between- and within-subjects designs. In addition, we give hands-on examples of how to compute these CIs and discuss their relation to classical t-tests. PMID:23826038

  11. Multivariate Effect Size Estimation: Confidence Interval Construction via Latent Variable Modeling

    ERIC Educational Resources Information Center

    Raykov, Tenko; Marcoulides, George A.

    2010-01-01

    A latent variable modeling method is outlined for constructing a confidence interval (CI) of a popular multivariate effect size measure. The procedure uses the conventional multivariate analysis of variance (MANOVA) setup and is applicable with large samples. The approach provides a population range of plausible values for the proportion of…

  12. Improved confidence intervals for the linkage disequilibrium method for estimating effective population size.

    PubMed

    Jones, A T; Ovenden, J R; Wang, Y-G

    2016-10-01

    The linkage disequilibrium method is currently the most widely used single sample estimator of genetic effective population size. The commonly used software packages come with two options, referred to as the parametric and jackknife methods, for computing the associated confidence intervals. However, little is known on the coverage performance of these methods, and the published data suggest there may be some room for improvement. Here, we propose two new methods for generating confidence intervals and compare them with the two in current use through a simulation study. The new confidence interval methods tend to be conservative but outperform the existing methods for generating confidence intervals under certain circumstances, such as those that may be encountered when making estimates using large numbers of single-nucleotide polymorphisms.

  13. Improved confidence intervals for the linkage disequilibrium method for estimating effective population size.

    PubMed

    Jones, A T; Ovenden, J R; Wang, Y-G

    2016-10-01

    The linkage disequilibrium method is currently the most widely used single sample estimator of genetic effective population size. The commonly used software packages come with two options, referred to as the parametric and jackknife methods, for computing the associated confidence intervals. However, little is known on the coverage performance of these methods, and the published data suggest there may be some room for improvement. Here, we propose two new methods for generating confidence intervals and compare them with the two in current use through a simulation study. The new confidence interval methods tend to be conservative but outperform the existing methods for generating confidence intervals under certain circumstances, such as those that may be encountered when making estimates using large numbers of single-nucleotide polymorphisms. PMID:27005004

  14. Pigeons' Memory for Number of Events: Effects of Intertrial Interval and Delay Interval Illumination

    ERIC Educational Resources Information Center

    Hope, Chris; Santi, Angelo

    2004-01-01

    In Experiment 1, pigeons were trained at a 0-s baseline delay to discriminate sequences of light flashes (illumination of the feeder) that varied in number but not time (2f/4s and 8f/4s). During training, the intertrial interval was illuminated by the houselight for Group Light, but it was dark for Group Dark. Testing conducted with dark delay…

  15. Confidence Intervals Make a Difference: Effects of Showing Confidence Intervals on Inferential Reasoning

    ERIC Educational Resources Information Center

    Hoekstra, Rink; Johnson, Addie; Kiers, Henk A. L.

    2012-01-01

    The use of confidence intervals (CIs) as an addition or as an alternative to null hypothesis significance testing (NHST) has been promoted as a means to make researchers more aware of the uncertainty that is inherent in statistical inference. Little is known, however, about whether presenting results via CIs affects how readers judge the…

  16. Nosewitness Identification: Effects of Lineup Size and Retention Interval

    PubMed Central

    Alho, Laura; Soares, Sandra C.; Costa, Liliana P.; Pinto, Elisa; Ferreira, Jacqueline H. T.; Sorjonen, Kimmo; Silva, Carlos F.; Olsson, Mats J.

    2016-01-01

    Although canine identification of body odor (BO) has been widely used as forensic evidence, the concept of nosewitness identification by human observers was only recently put to the test. The results indicated that BOs associated with male characters in authentic crime videos could later be identified in BO lineup tests well above chance. To further evaluate nosewitness memory, we assessed the effects of lineup size (Experiment 1) and retention interval (Experiment 2), using a forced-choice memory test. The results showed that nosewitness identification works for all lineup sizes (3, 5, and 8 BOs), but that larger lineups compromise identification performance in similarity to observations from eye- and earwitness studies. Also in line with previous eye- and earwitness studies, but in disagreement with some studies on odor memory, Experiment 2 showed significant forgetting between shorter retention intervals (15 min) and longer retention intervals (1-week) using lineups of five BOs. Altogether this study shows that identification of BO in a forensic setting is possible and has limits and characteristics in line with witness identification through other sensory modalities. PMID:27303317

  17. Naming, rehearsal, and interstimulus interval effects in memory processing.

    PubMed

    Wright, A A; Cook, R G; Rivera, J J; Shyan, M R; Neiworth, J J; Jitsumori, M

    1990-11-01

    Recognition memory was tested for lists of 6 briefly (0.08 s) presented pictures at different interstimulus intervals (ISI) of 0.08, 1, and 4 s. Experiment 1 showed a 16% performance increase (ISI effect) for increasing ISI for travel slide but not kaleidoscope pictures. Experiment 2 showed that learning names for the kaleidoscope pictures then resulted in a substantial (20%) ISI effect, not attributable solely to the added exposure to the pictures. Experiment 3 required names, color evaluations, or blank stares during list-memory presentations. Interviews established that the most effective memory strategy was chaining the names together, followed by repeating the most current name, and in turn followed by reliance upon only the sensory experience. All groups in Experiments 2 and 3, independent of ISI effects, showed U-shaped serial position functions. Rehearsal is shown to be nonessential and cannot be the general cause of the primary effect of the serial position function.

  18. Sample Size Planning for the Squared Multiple Correlation Coefficient: Accuracy in Parameter Estimation via Narrow Confidence Intervals

    ERIC Educational Resources Information Center

    Kelley, Ken

    2008-01-01

    Methods of sample size planning are developed from the accuracy in parameter approach in the multiple regression context in order to obtain a sufficiently narrow confidence interval for the population squared multiple correlation coefficient when regressors are random. Approximate and exact methods are developed that provide necessary sample size…

  19. Confidence intervals for a random-effects meta-analysis based on Bartlett-type corrections.

    PubMed

    Noma, Hisashi

    2011-12-10

    In medical meta-analysis, the DerSimonian-Laird confidence interval for the average treatment effect has been widely adopted in practice. However, it is well known that its coverage probability (the probability that the interval actually includes the true value) can be substantially below the target level. One particular reason is that the validity of the confidence interval depends on the assumption that the number of synthesized studies is sufficiently large. In typical medical meta-analyses, the number of studies is fewer than 20. In this article, we developed three confidence intervals for improving coverage properties, based on (i) the Bartlett corrected likelihood ratio statistic, (ii) the efficient score statistic, and (iii) the Bartlett-type adjusted efficient score statistic. The Bartlett and Bartlett-type corrections improve the large sample approximations for the likelihood ratio and efficient score statistics. Through numerical evaluations by simulations, these confidence intervals demonstrated better coverage properties than the existing methods. In particular, with a moderate number of synthesized studies, the Bartlett and Bartlett-type corrected confidence intervals performed well. An application to a meta-analysis of the treatment for myocardial infarction with intravenous magnesium is presented.

  20. Acute effects of intense interval training on running mechanics.

    PubMed

    Collins, M H; Pearsall, D J; Zavorsky, G S; Bateni, H; Turcotte, R A; Montgomery, D L

    2000-02-01

    The aims of this study were to determine if there are significant kinematic changes in running pattern after intense interval workouts, whether duration of recovery affects running kinematics, and whether changes in running economy are related to changes in running kinematics. Seven highly trained male endurance runners (VO2max = 72.3+/-3.3 ml x kg(-1) x min(-1); mean +/- s) performed three interval running workouts of 10 x 400 m at a speed of 5.94+/-0.19 m x s(-1) (356+/-11.2 m x min(-1)) with a minimum of 4 days recovery between runs. Recovery of 60, 120 or 180 s between each 400 m repetition was assigned at random. Before and after each workout, running economy and several kinematic variables were measured at speeds of 3.33 and 4.47 m x s(-1) (200 and 268 m x min(-1)). Speed was found to have a significant effect on shank angle, knee velocity and stride length (P < 0.05). Correlations between changes pre- and post-test for VO2 (ml x kg(-1) x min(-1)) and several kinematic variables were not significant (P > 0.05) at both speeds. In general, duration of recovery was not found to adversely affect running economy or the kinematic variables assessed, possibly because of intra-individual adaptations to fatigue.

  1. The naïve intuitive statistician: a naïve sampling model of intuitive confidence intervals.

    PubMed

    Juslin, Peter; Winman, Anders; Hansson, Patrik

    2007-07-01

    The perspective of the naïve intuitive statistician is outlined and applied to explain overconfidence when people produce intuitive confidence intervals and why this format leads to more overconfidence than other formally equivalent formats. The naïve sampling model implies that people accurately describe the sample information they have but are naïve in the sense that they uncritically take sample properties as estimates of population properties. A review demonstrates that the naïve sampling model accounts for the robust and important findings in previous research as well as provides novel predictions that are confirmed, including a way to minimize the overconfidence with interval production. The authors discuss the naïve sampling model as a representative of models inspired by the naïve intuitive statistician. PMID:17638502

  2. An Introduction to Confidence Intervals for Both Statistical Estimates and Effect Sizes.

    ERIC Educational Resources Information Center

    Capraro, Mary Margaret

    This paper summarizes methods of estimating confidence intervals, including classical intervals and intervals for effect sizes. The recent American Psychological Association (APA) Task Force on Statistical Inference report suggested that confidence intervals should always be reported, and the fifth edition of the APA "Publication Manual" (2001)…

  3. Variation of the Tully-Fisher relation as a function of the magnitude interval of a sample of galaxies

    NASA Astrophysics Data System (ADS)

    Ruelas-Mayorga, A.; Sánchez, L. J.; Trujillo-Lara, M.; Nigoche-Netro, A.; Echevarría, J.; García, A. M.; Ramírez-Vélez, J.

    2016-10-01

    In this paper we carry out a preliminary study of the dependence of the Tully-Fisher Relation (TFR) with the width and intensity level of the absolute magnitude interval of a limited sample of 2411 galaxies taken from Mathewson and Ford (Astrophys. J. Suppl. Ser. 107:97, 1996). The galaxies in this sample do not differ significantly in morphological type, and are distributed over an ˜ 11-magnitude interval (-24.4 < I < -13.0). We take as directives the papers by Nigoche-Netro et al. (Astron. Astrophys. 491:731, 2008; Mon. Not. R. Astron. Soc. 392:1060, 2009; Astron. Astrophys. 516:96, 2010) in which they study the dependence of the Kormendy (KR), the Fundamental Plane (FPR) and the Faber-Jackson Relations (FJR) with the magnitude interval within which the observed galaxies used to derive these relations are contained. We were able to characterise the behaviour of the TFR coefficients (α, β ) with respect to the width of the magnitude interval as well as with the brightness of the galaxies within this magnitude interval. We concluded that the TFR for this specific sample of galaxies depends on observational biases caused by arbitrary magnitude cuts, which in turn depend on the width and intensity of the chosen brightness levels.

  4. Short-Term Memory for Temporal Intervals: Contrasting Explanations of the Choose-Short Effect in Pigeons

    ERIC Educational Resources Information Center

    Pinto, Carlos; Machado, Armando

    2011-01-01

    To better understand short-term memory for temporal intervals, we re-examined the choose-short effect. In Experiment 1, to contrast the predictions of two models of this effect, the subjective shortening and the coding models, pigeons were exposed to a delayed matching-to-sample task with three sample durations (2, 6 and 18 s) and retention…

  5. Confidence intervals for population allele frequencies: the general case of sampling from a finite diploid population of any size.

    PubMed

    Fung, Tak; Keenan, Kevin

    2014-01-01

    The estimation of population allele frequencies using sample data forms a central component of studies in population genetics. These estimates can be used to test hypotheses on the evolutionary processes governing changes in genetic variation among populations. However, existing studies frequently do not account for sampling uncertainty in these estimates, thus compromising their utility. Incorporation of this uncertainty has been hindered by the lack of a method for constructing confidence intervals containing the population allele frequencies, for the general case of sampling from a finite diploid population of any size. In this study, we address this important knowledge gap by presenting a rigorous mathematical method to construct such confidence intervals. For a range of scenarios, the method is used to demonstrate that for a particular allele, in order to obtain accurate estimates within 0.05 of the population allele frequency with high probability (> or = 95%), a sample size of > 30 is often required. This analysis is augmented by an application of the method to empirical sample allele frequency data for two populations of the checkerspot butterfly (Melitaea cinxia L.), occupying meadows in Finland. For each population, the method is used to derive > or = 98.3% confidence intervals for the population frequencies of three alleles. These intervals are then used to construct two joint > or = 95% confidence regions, one for the set of three frequencies for each population. These regions are then used to derive a > or = 95%% confidence interval for Jost's D, a measure of genetic differentiation between the two populations. Overall, the results demonstrate the practical utility of the method with respect to informing sampling design and accounting for sampling uncertainty in studies of population genetics, important for scientific hypothesis-testing and also for risk-based natural resource management. PMID:24465792

  6. Effect of clozapine on interval timing and working memory for time in the peak-interval procedure with gaps.

    PubMed

    Buhusi, Catalin V; Meck, Warren H

    2007-02-22

    Previous research indicates that dopamine controls both the speed of an internal clock [Maricq, A.V., Church, R.M., 1983. The differential effects of haloperidol and methamphetamine on time estimation in the rat. Psychopharmacology 79, 10-15] and sharing of resources between the timer and other cognitive processes [Buhusi, C.V., 2003. Dopaminergic mechanisms of interval timing and attention. In: Meck, W.H. (Ed.), Functional and Neural Mechanisms of Interval Timing. CRC Press, Boca Raton, FL, pp. 317-338]. For example, dopamine agonist methamphetamine increases the speed of an internal clock and resets timing after a gap, while dopamine antagonist haloperidol decreases the speed of an internal clock and stops timing during a gap [Buhusi, C.V., Meck, W.H., 2002. Differential effects of methamphetamine and haloperidol on the control of an internal clock. Behav. Neurosci. 116, 291-297]. Using a 20-s peak-interval procedure with gaps we examined the acute effects of clozapine (2.0mg/kg i.p.), which exerts differential effects on dopamine and serotonin in the cortex and striatum, two brain areas involved in interval timing and working memory. Relative to saline, clozapine injections shifted the response functions leftward both in trials with and without gaps, suggesting that clozapine increased the speed of an internal clock and facilitated the maintenance of the pre-gap interval in working memory. These results suggest that clozapine exerts effects in different brain areas in a manner that allows for the pharmacological separation of clock speed and working memory as a function of peak trials without and with gaps.

  7. Population Validity and Cross-Validity: Applications of Distribution Theory for Testing Hypotheses, Setting Confidence Intervals, and Determining Sample Size

    ERIC Educational Resources Information Center

    Algina, James; Keselman, H. J.

    2008-01-01

    Applications of distribution theory for the squared multiple correlation coefficient and the squared cross-validation coefficient are reviewed, and computer programs for these applications are made available. The applications include confidence intervals, hypothesis testing, and sample size selection. (Contains 2 tables.)

  8. ON-LINE TOOLS FOR PROPER VERTICAL POSITIONING OF VERTICAL SAMPLING INTERVALS DURING SITE ASSESSMENT: MEETING IN MONTGOMERY, ALABAMA

    EPA Science Inventory

    This presentation, On-Line Tools for Proper Vertical Positioning of Sampling Intervals During Site Assessment, describes an approach to locating monitoring wells that is based on application of ground water models. The ideal use of both the model and site assessment funds is to ...

  9. Which are the best VO2 sampling intervals to characterize low to severe swimming intensities?

    PubMed

    de Jesus, K; Guidetti, L; de Jesus, K; Vilas-Boas, J P; Baldari, C; Fernandes, R J

    2014-11-01

    Cardiorespiratory response in swimming has been used to better understand aerobic performance, especially by assessing oxygen uptake (VO2). The current study aimed to compare different VO2 time-averaging intervals throughout low to severe swimming intensities, hypothesizing that VO2 values are similar for different time averages at low to moderate and heavy swimming intensities, but not for the severe domain. 20 male trained swimmers completed an incremental protocol of 7×200 m until exhaustion (0.05 m/s increments and 30 s intervals). VO2 was measured by a portable gas analyser connected to a snorkel system. 6 time average intervals (breath-by-breath, 5, 10, 15, 20 and 30 s) were compared for all the protocol steps. Breath-by-breath and 5 s average exhibited higher VO2 values than averages≥10 s for all swimming intensities (P≤0.02; partial η(2)≤0.28). VO2 values did not differ between 10, 15, 20 and 30 s averages throughout the incremental protocol (P>0.05; partial η(2)≤0.05). Furthermore, 10 and 15 s averages showed the lowest VO2 mean difference (0.19 mL( · )kg(-1 · )min(-1)). For the 6 time average intervals analysed, 10 and 15 s averages were those that showed the lowest changes on VO2 values. We recommended the use of 10 and 15 s time averaging intervals to determine relevant respiratory gas exchange parameters along a large spectrum of swimming intensities. PMID:24892654

  10. Which are the best VO2 sampling intervals to characterize low to severe swimming intensities?

    PubMed

    de Jesus, K; Guidetti, L; de Jesus, K; Vilas-Boas, J P; Baldari, C; Fernandes, R J

    2014-11-01

    Cardiorespiratory response in swimming has been used to better understand aerobic performance, especially by assessing oxygen uptake (VO2). The current study aimed to compare different VO2 time-averaging intervals throughout low to severe swimming intensities, hypothesizing that VO2 values are similar for different time averages at low to moderate and heavy swimming intensities, but not for the severe domain. 20 male trained swimmers completed an incremental protocol of 7×200 m until exhaustion (0.05 m/s increments and 30 s intervals). VO2 was measured by a portable gas analyser connected to a snorkel system. 6 time average intervals (breath-by-breath, 5, 10, 15, 20 and 30 s) were compared for all the protocol steps. Breath-by-breath and 5 s average exhibited higher VO2 values than averages≥10 s for all swimming intensities (P≤0.02; partial η(2)≤0.28). VO2 values did not differ between 10, 15, 20 and 30 s averages throughout the incremental protocol (P>0.05; partial η(2)≤0.05). Furthermore, 10 and 15 s averages showed the lowest VO2 mean difference (0.19 mL( · )kg(-1 · )min(-1)). For the 6 time average intervals analysed, 10 and 15 s averages were those that showed the lowest changes on VO2 values. We recommended the use of 10 and 15 s time averaging intervals to determine relevant respiratory gas exchange parameters along a large spectrum of swimming intensities.

  11. Optical effects module and passive sample array

    NASA Technical Reports Server (NTRS)

    Linton, R. C.

    1983-01-01

    The Optical Effects Module (OEM) has the objective to monitor the effects of the deposition and adhesion of both molecular species and particles on optical surfaces in the Shuttle cargo bay environment. The OEM performs inflight measurements of the ultraviolet (253.7 nm) transmittance and diffuse reflectance of five optical samples at regular intervals throughout the orbital mission. Most of the obtained results indicates or implies the absence of a significant accumulation of contamination other than particulates on the samples. The contaminant species (or particulates) adhering to the samples of the Passive Sample Array (PSA) were identified by means of Auger and X-ray energy dispersive analyses. The elements silicon, chlorine, and phosphorus were discovered.

  12. Effect of acute interval sprinting exercise on postprandial lipemia of sedentary young men

    PubMed Central

    Chu, Aaron; Boutcher, Yati N; Boutcher, Stephen H

    2016-01-01

    [Purpose] Postprandial lipemia (PPL) contributesto the development of atherosclerosis. In females, repeated 8-second bouts of interval sprinting exercise reduced PPL, however, the effect of 8-second bouts of interval sprinting on PPL of overweight males is undetermined. Thus, the effect of 8-secondsof interval sprinting for 20 min, the night before ingestion of a high-fat meal (HFM), on plasma triacylglycerol(TG) levelswas examined. [Methods] Ten overweight males acted as participants (BMI = 26±3.0kg/m2, age 22 ± 2.5 years). A crossover design was employed withinterval sprinting and a noexercise condition separated by 7days. Participants consumed a milkshake (high-fat meal;HFM = 4170 kJ/993 Kcal) the morning after an overnight fast, followed by 4 hourly blood samples. Participants performedone bout of interval sprinting (8seconds sprinting at 110-115rpm, 12seconds active recovery at ~60rpm for 20 minutes) the evening before the consumption of the HFM. [Results] Postprandial TG was 22.5% lower in the interval sprinting compared to the noexercise condition when comparing the change in total area under the curve (ΔAUCT): ISE(7.15±1.90mmolL-1h-1) versus noexercise (9.22±3.44mmolL-1h-1), p=.014. The correlation between fasting TG levels in the noexercise condition and total reduction in AUCT between the conditions was significant (r=.87, p=.001). [Conclusion] One 20-min bout of interval sprinting,the night before consumption of a HFM,significantly attenuated the PPL response of sedentary males. PMID:27298807

  13. Conditional sampling schemes based on the Variable Interval Time Averaging (VITA) algorithm

    NASA Astrophysics Data System (ADS)

    Morrison, J. F.; Tsai, H. M.; Bradshaw, P.

    1986-08-01

    The variable interval time averaging (VITA) algorithm was tested in a variety of boundary layers for its ability to detect motions principally involved in the production of shear stress. A VITA+LEVEL scheme (which uses a variance and level criterion) was devised and is shown to produce length scale statistics that are independent of the conditioning criteria, where those from the VITA scheme are not.

  14. Central tendency effects in time interval reproduction in autism

    PubMed Central

    Karaminis, Themelis; Cicchini, Guido Marco; Neil, Louise; Cappagli, Giulia; Aagten-Murphy, David; Burr, David; Pellicano, Elizabeth

    2016-01-01

    Central tendency, the tendency of judgements of quantities (lengths, durations etc.) to gravitate towards their mean, is one of the most robust perceptual effects. A Bayesian account has recently suggested that central tendency reflects the integration of noisy sensory estimates with prior knowledge representations of a mean stimulus, serving to improve performance. The process is flexible, so prior knowledge is weighted more heavily when sensory estimates are imprecise, requiring more integration to reduce noise. In this study we measure central tendency in autism to evaluate a recent theoretical hypothesis suggesting that autistic perception relies less on prior knowledge representations than typical perception. If true, autistic children should show reduced central tendency than theoretically predicted from their temporal resolution. We tested autistic and age- and ability-matched typical children in two child-friendly tasks: (1) a time interval reproduction task, measuring central tendency in the temporal domain; and (2) a time discrimination task, assessing temporal resolution. Central tendency reduced with age in typical development, while temporal resolution improved. Autistic children performed far worse in temporal discrimination than the matched controls. Computational simulations suggested that central tendency was much less in autistic children than predicted by theoretical modelling, given their poor temporal resolution. PMID:27349722

  15. Anxiolytic-like effects of leptin on fixed interval responding.

    PubMed

    Tyree, Susan M; Munn, Robert G K; McNaughton, Neil

    2016-09-01

    Leptin has been shown to affect energy homeostasis, learning and memory, and some models of anxiolytic action. However, leptin has produced inconsistent results in previous non-operant behavioural tests of anxiety. Here, we test the anxiolytic potential of leptin in an operant paradigm that has produced positive results across all classes of anxiolytic so far tested. Rats were tested in the Fixed Interval 60 Seconds (FI60) task following administration of 0/0.5/1.0mg/kg (i.p.) leptin or an active anxiolytic control of 5mg/kg (i.p.) chlordiazepoxide (CDP). By the end of the 14days of testing in the FI60 task, 0.5mg/kg leptin released suppressed responding in a manner similar to CDP, and 1.0mg/kg leptin produced a relative depression in responding, a similar outcome pattern to previously tested 5HT-agonist anxiolytics. This suggests that leptin behaves similarly to established serotonergic anxiolytics such as buspirone and fluoxetine; with the delay in development of effect during testing, and the inverted-U dose-response curve explaining the inconsistent behaviour of leptin in behavioural tests of anxiety, as this type of pattern is common to serotonergic anxiolytics. PMID:27180106

  16. Accuracy in Parameter Estimation for the Root Mean Square Error of Approximation: Sample Size Planning for Narrow Confidence Intervals.

    PubMed

    Kelley, Ken; Lai, Keke

    2011-02-01

    The root mean square error of approximation (RMSEA) is one of the most widely reported measures of misfit/fit in applications of structural equation modeling. When the RMSEA is of interest, so too should be the accompanying confidence interval. A narrow confidence interval reveals that the plausible parameter values are confined to a relatively small range at the specified level of confidence. The accuracy in parameter estimation approach to sample size planning is developed for the RMSEA so that the confidence interval for the population RMSEA will have a width whose expectation is sufficiently narrow. Analytic developments are shown to work well with a Monte Carlo simulation study. Freely available computer software is developed so that the methods discussed can be implemented. The methods are demonstrated for a repeated measures design where the way in which social relationships and initial depression influence coping strategies and later depression are examined.

  17. Natural Course of Chlamydia trachomatis Bacterial Load in the Time Interval between Screening and Treatment in Anogenital Samples

    PubMed Central

    Dirks, J. A. M. C.; van Liere, G. A. F. S.; Bogers, S.; Dukers-Muijrers, N. H. T. M.; Wolffs, P. F. G.; Hoebe, C. J. P. A.

    2015-01-01

    Introduction Although Chlamydia trachomatis (CT) is the most common bacterial sexually transmitted infection worldwide, little is known about the natural course of the bacterial load during infection. We investigated the natural course of the bacterial load in the interval between screening and returning for treatment in genital and anorectal CT-infections. Materials & Methods CT-positive patients, visiting our STI-clinic in the Netherlands from June 2011–January 2014, provided a second urogenital and/or anorectal sample when returning for treatment (diagnostic sample = T1; treatment sample = T2). Patient-record provided data about the days between samples and the date of last unsafe sex. Included patients were ≥18 years old, HIV-negative and did not report antibiotic use in the study-interval. CT load was quantified using qPCR. CT load was log-transformed, and a CT load difference (Δ-CT load) of >1 log was deemed clinically relevant. Chi-square test compared load category distributions over time (decrease/equal/increase), between sample types. Results 274 patients provided 296 paired samples. Majority of samples had a stable CT load in the interval T1-T2 (66.3%, 73.1% and 48.6% for vaginal swabs, urine and anorectal swabs resp. p = 0.07). Load decreased in 17–41% of patients, while ±10% of patients showed an increase in CT load. No association between Δ-CT load and the interval T1-T2 was observed. Large variations can be seen in CT load at T1 and over time. Discussion The majority (±90%) of patients have a stable or decreasing CT load in the time interval between screening and returning for treatment. The number of days between sampling was not associated with change in CT load. In the first month after the last unsafe sex, only stable CT loads were seen. Our data seems to indicate that when most patients visit an STI-clinic, recommended 2 weeks after infection, the infection has already been established or is in its downward phase. PMID:26713628

  18. Erythromycin potentiates PR interval prolonging effect of verapamil in the rat: A pharmacodynamic drug interaction

    SciTech Connect

    Dakhel, Yaman; Jamali, Fakhreddin . E-mail: fjamali@ualberta.ca

    2006-07-01

    Calcium channel blockers and macrolide antibiotics account for many drug interactions. Anecdotal reports suggest interactions between the two resulting in severe side effects. We studied the interaction between verapamil and erythromycin in the rat to see whether it occurs at the pharmacokinetics or pharmacodynamic level. Adult male Sprague-Dawley rats received doses of 1 mg/kg verapamil or 100 mg/kg erythromycin alone or in combination (n = 6/group). Serial blood samples (0-6 h) were taken for determination of the drug concentrations using HPLC. Electrocardiograms were recorded (0-6 h) through subcutaneously inserted lead II. Binding of the drugs to plasma proteins was studied using spiked plasma. Verapamil prolonged PR but not QT interval. Erythromycin prolonged QT but not PR interval. The combination resulted in a significant increase in PR interval prolongation and AV node blocks but did not further prolong QT interval. Pharmacokinetics and protein binding of neither drug were altered by the other. Our rat data confirm the anecdotal human case reports that combination of erythromycin and verapamil can result in potentiation of the cardiovascular response. The interaction appears to be at the pharmacodynamic rather than pharmacokinetic level hence may be extrapolated to other calcium channel antagonists.

  19. The Acute Effects of Interval-Type Exercise on Glycemic Control in Type 2 Diabetes Subjects: Importance of Interval Length. A Controlled, Counterbalanced, Crossover Study

    PubMed Central

    Jakobsen, Ida; Solomon, Thomas P. J.

    2016-01-01

    Interval-type exercise is effective for improving glycemic control, but the optimal approach is unknown. The purpose of this study was to determine the importance of the interval length on changes in postprandial glycemic control following a single exercise bout. Twelve subjects with type 2 diabetes completed a cross-over study with three 1-hour interventions performed in a non-randomized but counter-balanced order: 1) Interval walking consisting of repeated cycles of 3 min slow (aiming for 54% of Peak oxygen consumption rate [VO2peak]) and 3 min fast (aiming for 89% of VO2peak) walking (IW3); 2) Interval walking consisting of repeated cycles of 1 min slow and 1 min fast walking (IW1) and 3) No walking (CON). The exercise interventions were matched with regards to walking speed, and VO2 and heart rate was assessed throughout all interventions. A 4-hour liquid mixed meal tolerance test commenced 30 min after each intervention, with blood samples taken regularly. IW3 and IW1 resulted in comparable mean VO2 and heart rates. Overall mean postprandial blood glucose levels were lower after IW3 compared to CON (10.3±3.0 vs. 11.1±3.3 mmol/L; P < 0.05), with no significant differences between IW1 (10.5±2.8 mmol/L) and CON or IW3 and IW1 (P > 0.05 for both). Conversely blood glucose levels at specific time points during the MMTT differed significantly following both IW3 and IW1 as compared to CON. Our findings support the previously found blood glucose lowering effect of IW3 and suggest that reducing the interval length, while keeping the walking speed and time spend on fast and slow walking constant, does not result in additional improvements. Trial Registration ClinicalTrials.gov NCT02257190 PMID:27695119

  20. Reinforcer concentration effects on a fixed-interval schedule.

    PubMed

    Blomeley, Frances J; Lowe, C F; Wearden, J H

    2004-07-30

    Four rats received training on a mixed FI 30-s FI 150-s schedule, where the different FI values were associated with different levers. During baseline, the reinforcer was a 30% concentration of condensed milk. During subsequent testing sessions, the reinforcer concentration was varied within sessions over values of 10, 30, 50, and 70%. Measures of behaviour were taken from the FI 30-s lever during trials where the reinforcer was delivered for responses on the other lever. Increasing the reinforcer concentration which began the interval (a) increased the time to start responding in the interval, and (b) increased the location of the response peak on the FI 30-s lever (often to values well above 30s). Response rate at the peak, and spread of the response rate versus time function, changed much less with reinforcer concentration. The data are discussed relative to predictions derived from Scalar Expectancy Theory, the Behavioural Theory of Timing, and the Tuned-trace model.

  1. Age effects in discrimination of intervals within rhythmic tone sequences.

    PubMed

    Fitzgibbons, Peter J; Gordon-Salant, Sandra

    2015-01-01

    This study measured listener sensitivity to increments of a target inter-onset interval (IOI) embedded within tone sequences that featured different rhythmic patterns. The sequences consisted of six 50-ms 1000-Hz tone bursts separated by silent intervals that were adjusted to create different timing patterns. Control sequences were isochronous, with all tonal IOIs fixed at either 200 or 400 ms, while other patterns featured combinations of the two IOIs arranged to create different sequential tonal groupings. Duration difference limens in milliseconds for increments of a single sequence IOI were measured adaptively by adjusting the duration of an inter-tone silent interval. Specific target IOIs within sequences differed across discrimination conditions. Listeners included younger normal-hearing adults and groups of older adults with and without hearing loss. Discrimination performance measured for each of the older groups of listeners was observed to be equivalent, with each group exhibiting significantly poorer discrimination performance than the younger listeners in each sequence condition. Additionally, the specific influence of variable rhythmic grouping on temporal sensitivity was found to be greatest among older listeners. PMID:25618068

  2. A Further Assessment of Momentary Time-Sampling across Extended Interval Lengths

    ERIC Educational Resources Information Center

    Alvero, Alicia M.; Rappaport, Eva; Taylor, Matthew A.

    2011-01-01

    The current study compared the estimation of momentary time-sampling (MTS) to actual safety performance of three ergonomic responses: back, shoulder, and feet. Actual safety performance was established for the five participants by measuring the target responses with a continuous procedure. MTS 90, 105, 120, 135, 150, 165, 180, 195, 210, 240, and…

  3. Sample interval modulation for the simultaneous acquisition of displacement vector data in magnetic resonance elastography: theory and application.

    PubMed

    Klatt, Dieter; Yasar, Temel K; Royston, Thomas J; Magin, Richard L

    2013-12-21

    SampLe Interval Modulation-magnetic resonance elastography (SLIM-MRE) is introduced for simultaneously encoding all three displacement projections of a monofrequency vibration into the MR signal phase. In SLIM-MRE, the individual displacement components are observed using different sample intervals. In doing so, the components are modulated with different apparent frequencies in the MR signal phase expressed as a harmonic function of the start time of the motion encoding gradients and can thus be decomposed by applying a Fourier transform to the sampled multidirectional MR phases. In this work, the theoretical foundations of SLIM-MRE are presented and the new idea is implemented using a high field (11.7 T) vertical bore magnetic resonance imaging system on an inhomogeneous agarose gel phantom sample. The local frequency estimation-derived stiffness values were the same within the error margins for both the new SLIM-MRE method and for conventional MRE, while the number of temporally-resolved MRE experiments needed for each study was reduced from three to one. In this work, we present for the first time, monofrequency displacement data along three sensitization directions that were acquired simultaneously and stored in the same k-space.

  4. Food and Insulin Effect on QT/QTC Interval of ECG

    ClinicalTrials.gov

    2014-08-19

    Effects of Different Meals on the QT/QTc Interval; Insulin and Oral Hypoglycemic [Antidiabetic] Drugs Causing Adverse Effects in Therapeutic Use; C-Peptide Effects on the QT/QTc Interval; Moxifloxacin ECG Profile in Fed and Fasted State; Japanese vs. Caucasian TQT Comparison

  5. Evaluation of the effect on cardiac repolarization (QTc interval) of oncologic drugs.

    PubMed

    Morganroth, J

    2007-01-01

    The 12-lead electrocardiograph (ECG) is the standard safety measurement used in clinical trials to identify drug-induced cardiac adverse effects. Drug-induced prolongation of the QTc interval (the measure of cardiac repolarization change), when excessive and in conjunction with the right risk factors, can degenerate into a polymorphic ventricular tachycardia called torsades de pointes and has become a new focus for new drug development. The assessment of an ECG in clinical practice using machine-defined QTc duration is intrinsically unreliable. Current regulatory concepts have focused on the need for measuring ECG intervals using manual techniques using digital processing in a central ECG laboratory. The QT interval is subject to a large degree of spontaneous variability requiring attention to basic clinical trial design issues such as sample size (use as large a cohort as possible), frequency of measurements taken (at least three to six ECGs at baseline and at many time points on therapy with pharmacokinetic samples if possible), and their accuracy. Since most oncologic products are cytotoxic, a Thorough or Dedicated ECG Trial cannot be conducted and in the usual trail, especially in phase I, all changes seen on the ECG will be attributed to the new oncology drug. For most nononcologic drugs, there is regulatory guidance on how much an effect on QTc duration might be related to the risk of cardiac toxicity. For oncology products, the central tendency magnitude and proportion of outliers needs to be well defined to construct a label if the risk-benefit analysis leads to marketing approval. Clinical cardiac findings such as syncope, ventricular tachyarrhythmias, and other cardiac effects will be important in this analysis. PMID:17117723

  6. A Comparison of Methods for Estimating Confidence Intervals for Omega-Squared Effect Size

    ERIC Educational Resources Information Center

    Finch, W. Holmes; French, Brian F.

    2012-01-01

    Effect size use has been increasing in the past decade in many research areas. Confidence intervals associated with effect sizes are encouraged to be reported. Prior work has investigated the performance of confidence interval estimation with Cohen's d. This study extends this line of work to the analysis of variance case with more than two…

  7. The Effects of Initial Interval Size on the Efficacy of DRO Schedules of Reinforcement.

    ERIC Educational Resources Information Center

    Repp, Alan C.; And Others

    1991-01-01

    This study examined effect of initial differential reinforcement of other behavior (DRO) intervals on disruptive behavior of nine students with moderate disabilities. Results indicate initial DRO value equal to the mean number of intervals between responses in baseline was much more effective than a value twice that size. (Author/PB)

  8. The effect of inter-set rest intervals on resistance exercise-induced muscle hypertrophy.

    PubMed

    Henselmans, Menno; Schoenfeld, Brad J

    2014-12-01

    Due to a scarcity of longitudinal trials directly measuring changes in muscle girth, previous recommendations for inter-set rest intervals in resistance training programs designed to stimulate muscular hypertrophy were primarily based on the post-exercise endocrinological response and other mechanisms theoretically related to muscle growth. New research regarding the effects of inter-set rest interval manipulation on resistance training-induced muscular hypertrophy is reviewed here to evaluate current practices and provide directions for future research. Of the studies measuring long-term muscle hypertrophy in groups employing different rest intervals, none have found superior muscle growth in the shorter compared with the longer rest interval group and one study has found the opposite. Rest intervals less than 1 minute can result in acute increases in serum growth hormone levels and these rest intervals also decrease the serum testosterone to cortisol ratio. Long-term adaptations may abate the post-exercise endocrinological response and the relationship between the transient change in hormonal production and chronic muscular hypertrophy is highly contentious and appears to be weak. The relationship between the rest interval-mediated effect on immune system response, muscle damage, metabolic stress, or energy production capacity and muscle hypertrophy is still ambiguous and largely theoretical. In conclusion, the literature does not support the hypothesis that training for muscle hypertrophy requires shorter rest intervals than training for strength development or that predetermined rest intervals are preferable to auto-regulated rest periods in this regard.

  9. Chronic Treatment with Haloperidol Induces Deficits in Working Memory and Feedback Effects of Interval Timing

    ERIC Educational Resources Information Center

    Lustig, C.; Meck, W.H.

    2005-01-01

    Normal participants (n=5) having no experience with antipsychotic drugs and medicated participants (n=5) with clinical experience with chronic low doses of haloperidol (3-10mg/day for 2-4 months) in the treatment of neuroses were evaluated for the effects of inter-trial interval (ITI) feedback on a discrete-trials peak-interval timing procedure.…

  10. Assessing Mediational Models: Testing and Interval Estimation for Indirect Effects

    ERIC Educational Resources Information Center

    Biesanz, Jeremy C.; Falk, Carl F.; Savalei, Victoria

    2010-01-01

    Theoretical models specifying indirect or mediated effects are common in the social sciences. An indirect effect exists when an independent variable's influence on the dependent variable is mediated through an intervening variable. Classic approaches to assessing such mediational hypotheses (Baron & Kenny, 1986; Sobel, 1982) have in recent years…

  11. Confidence intervals for similarity values determined for clonedSSU rRNA genes from environmental samples

    SciTech Connect

    Fields, M.W.; Schryver, J.C.; Brandt, C.C.; Yan, T.; Zhou, J.Z.; Palumbo, A.V.

    2007-04-02

    The goal of this research was to investigate the influenceof the error rate of sequence determination on the differentiation ofcloned SSU rRNA gene sequences for assessment of community structure. SSUrRNA cloned sequences from groundwater samples that represent differentbacterial divisions were sequenced multiple times with the samesequencing primer. From comparison of sequence alignments with unediteddata, confidence intervals were obtained from both a adouble binomial Tmodel of sequence comparison and by non-parametric methods. The resultsindicated that similarity values below 0.9946 arelikely derived fromdissimilar sequences at a confidence level of 0.95, and not sequencingerrors. The results confirmed that screening by direct sequencedetermination could be reliably used to differentiate at the specieslevel. However, given sequencing errors comparable to those seen in thisstudy, sequences with similarities above 0.9946 should be treated as thesame sequence if a 95 percent confidence is desired.

  12. Estimation of the Time Interval between the Administration of Heroin and the Sampling of Blood in Chronic Inhalers.

    PubMed

    Dubois, Nathalie; Hallet, Claude; Seidel, Laurence; Demaret, Isabelle; Luppens, David; Ansseau, Marc; Rozet, Eric; Albert, Adelin; Hubert, Philippe; Charlier, Corinne

    2015-05-01

    To develop a model for estimating the time delay between last heroin consumption and blood sampling in chronic drug users. Eleven patients, all heroin inhalers undergoing detoxification, were included in the study. Several plasma samples were collected during the detoxification procedure and analyzed for the heroin metabolites 6-acetylmorphine (6AM), morphine (MOR), morphine-6-glucuronide (M6G) and morphine-3-glucuronide (M3G), according to a UHPLC/MSMS method. The general linear mixed model was applied to time-related concentrations and a pragmatic four-step delay estimation approach was proposed based on the simultaneous presence of metabolites in plasma. Validation of the model was carried out using the jackknife technique on the 11 patients, and on a group of 7 test patients. Quadratic equations were derived for all metabolites except 6AM. The interval delay estimation was 2-4 days when only M3G present in plasma, 1-2 days when M6G and M3G were both present, 0-1 day when MOR, M6G and M3G were present and <2 h for all metabolites present. The 'jackknife' correlation between declared and actual estimated delays was 0.90. The overall precision of the delay estimates was 8-9 h. The delay between last heroin consumption and blood sampling in chronic drug users can be satisfactorily predicted from plasma heroin metabolites.

  13. Contextual effects in interval-duration judgements in vision, audition and touch.

    PubMed

    Burr, David; Della Rocca, Eleonora; Rocca, Eleonora Della; Morrone, M Concetta

    2013-09-01

    We examined the effect of temporal context on discrimination of intervals marked by auditory, visual and tactile stimuli. Subjects were asked to compare the duration of the interval immediately preceded by an irrelevant "distractor" stimulus with an interval with no distractor. For short interval durations, the presence of the distractor affected greatly the apparent duration of the test stimulus: short distractors caused the test interval to appear shorter and vice versa. For very short reference durations (≤ 100 ms), the contextual effects were large, changing perceived duration by up to a factor of two. The effect of distractors reduced steadily for longer reference durations, to zero effect for durations greater than 500 ms. We found similar results for intervals defined by visual flashes, auditory tones and brief finger vibrations, all falling to zero effect at 500 ms. Under appropriate conditions, there were strong cross-modal interactions, particularly from audition to vision. We also measured the Weber fractions for duration discrimination and showed that under the conditions of this experiment, Weber fractions decreased steadily with duration, following a square-root law, similarly for all three modalities. The magnitude of the effect of the distractors on apparent duration correlated well with Weber fraction, showing that when duration discrimination was relatively more precise, the context dependency was less. The results were well fit by a simple Bayesian model combining noisy estimates of duration with the action of a resonance-like mechanism that tended to regularize the sound sequence intervals.

  14. Behavioral contrast in fixed-interval components: effects of extinction-component duration.

    PubMed Central

    de Rose, J C

    1986-01-01

    Seven albino rats were exposed to a multiple schedule of reinforcement in which the two components (fixed interval and extinction) alternated such that a presentation of the extinction component followed each fixed-interval reinforcement. In baseline sessions, the duration of the extinction component was constant and always one-third of the fixed-interval value. Probe sessions contained a probe segment in which the duration of the extinction component was increased; the response rate in fixed-interval components during the probe segment was compared with the response rate in the segments preceding and following the probe. The effect of increasing the duration of the extinction component was studied under three values of fixed interval: 30 s, 120 s, and 18 s, in three successive conditions. Response rate within fixed intervals was a direct function of duration of the extinction component. Pausing at the beginning of the fixed interval decreased as extinction duration increased. These effects were larger and more consistent for the shorter fixed-interval values (18 s and 30 s). These results indicate a functional relation between relative component duration and responding. For the component providing more frequent reinforcement, this could be stated as an inverse relationship between relative component duration and response rate. This relation is similar to findings regarding the ratio of trial and intertrial duration in Pavlovian conditioning procedures, and suggests that behavioral contrast may be related to Pavlovian contingencies underlying the multiple schedule. PMID:3958663

  15. Extended recency effect extended: blocking, presentation mode, and retention interval.

    PubMed

    Glidden, L M; Pawelski, C; Mar, H; Zigman, W

    1979-07-01

    The effect of blocking of stimulus items on the free recall of EMR adolescents was examined. In Experiment 1 a multitrial free-recall list of 15 pictures was presented either simultaneously in groups of 3, or sequentially, one at a time. Consistent ordering was used in both conditions, so that on each trial, each item in each set of 3 pictures was presented contiguously with the other 2 items from that set. In addition, recall came immediately or after a filled or unfilled delay of 24.5 seconds. Results showed that simultaneous presentation led to higher recall, subjective organization, and clustering than did sequential presentation, but analysis of serial-position curves showed a much reduced extended recency effect in comparison with previous studies. Experiment 2 was designed to determine whether the cause of the reduced extended recency was the use of pictures rather than words as stimuli. Stimuli were presented either as pictures, as pictures with auditory labels, or as words with auditory labels, with both simultaneous and consistent ordering for all conditions. Results indicated a strong extended recency effect for all groups, eliminating presentation mode as a causal factor in the data of Experiment 1. We concluded that blocking leads to increased organization and recall over a variety of presentation modes, rates, and block sizes.

  16. Revisiting the Effect of Nicotine on Interval Timing

    PubMed Central

    Daniels, Carter W.; Watterson, Elizabeth; Garcia, Raul; Mazur, Gabriel J.; Brackney, Ryan J.; Sanabria, Federico

    2015-01-01

    This paper reviews the evidence for nicotine-induced acceleration of the internal clock when timing in the seconds-to-minutes timescale, and proposes an alternative explanation to this evidence: that nicotine reduces the threshold for responses that result in more reinforcement. These two hypotheses were tested in male Wistar rats using a novel timing task. In this task, rats were trained to seek food at one location after 8 s since trial onset and at a different location after 16 s. Some rats received the same reward at both times (group SAME); some received a larger reward at 16 s (group DIFF). Steady baseline performance was followed by 3 days of subcutaneous nicotine administration (0.3 mg/kg), baseline recovery, and an antagonist challenge (mecamylamine, 1.0 mg/kg). Nicotine induced a larger, immediate reduction in latencies to switch (LTS) in group DIFF than in group SAME. This effect was sustained throughout nicotine administration. Mecamylamine administration and discontinuation of nicotine rapidly recovered baseline performance. These results support a response-threshold account of nicotinic disruption of timing performance, possibly mediated by nicotinic acetylcholine receptors. A detailed analysis of the distribution of LTSs suggests that anomalous effects of nicotine on LTS dispersion may be due to loss of temporal control of behavior. PMID:25637907

  17. Psycho-Physical Effects of Varied Rest Intervals Following Warm-Up

    ERIC Educational Resources Information Center

    Aronchick, Joel; Burke, Edmund J.

    1977-01-01

    An assessment of the effects of rest intervals of varying lengths following a five minute warm-up revealed no significant differeence among them for perceived exertion, heart rate, and state anxiety. (MB)

  18. Temporal control in rats: analysis of nonlocalized effects from short interfood intervals.

    PubMed

    Higa, J J; Pierson, D

    1998-07-01

    The present experiment analyzed temporal control of postreinforcement pause duration during within-session changes in the criterion for reinforcement (interfood interval, IFI). Analysis of interval-by-interval changes in the pause revealed localized and nonlocalized effects from short intervals that caused specific changes in performance. In Phase 1, rats were presented with five consecutive 15-s IFIs intercalated into a series of 60-s IFIs. The 15-s set decreased the pause in adjacent and more remote 60-s intervals. In Phase 2, two sets of 15-s intervals were intercalated. The spacing between the two sets varied so that 0, 5, 10, or 15 60-s IFIs separated the sets. The postreinforcement pause tracked all changes in the IFI duration, and the localized effect from a short set extended beyond the next interval to the next few 60-s IFIs. Effects from one set, however, did not combine with a second set: Changes in the pause after two sets were the same regardless of the spacing between sets.

  19. The dose delivery effect of the different Beam ON interval in FFF SBRT: TrueBEAM

    NASA Astrophysics Data System (ADS)

    Tawonwong, T.; Suriyapee, S.; Oonsiri, S.; Sanghangthum, T.; Oonsiri, P.

    2016-03-01

    The purpose of this study is to determine the dose delivery effect of the different Beam ON interval in Flattening Filter Free Stereotactic Body Radiation Therapy (FFF-SBRT). The three 10MV-FFF SBRT plans (2 half rotating Rapid Arc, 9 to10 Gray/Fraction) were selected and irradiated in three different intervals (100%, 50% and 25%) using the RPM gating system. The plan verification was performed by the ArcCHECK for gamma analysis and the ionization chamber for point dose measurement. The dose delivery time of each interval were observed. For gamma analysis (2%&2mm criteria), the average percent pass of all plans for 100%, 50% and 25% intervals were 86.1±3.3%, 86.0±3.0% and 86.1±3.3%, respectively. For point dose measurement, the average ratios of each interval to the treatment planning were 1.012±0.015, 1.011±0.014 and 1.011±0.013 for 100%, 50% and 25% interval, respectively. The average dose delivery time was increasing from 74.3±5.0 second for 100% interval to 154.3±12.6 and 347.9±20.3 second for 50% and 25% interval, respectively. The same quality of the dose delivery from different Beam ON intervals in FFF-SBRT by TrueBEAM was illustrated. While the 100% interval represents the breath-hold treatment technique, the differences for the free-breathing using RPM gating system can be treated confidently.

  20. Approximate confidence intervals for moment-based estimators of the between-study variance in random effects meta-analysis.

    PubMed

    Jackson, Dan; Bowden, Jack; Baker, Rose

    2015-12-01

    Moment-based estimators of the between-study variance are very popular when performing random effects meta-analyses. This type of estimation has many advantages including computational and conceptual simplicity. Furthermore, by using these estimators in large samples, valid meta-analyses can be performed without the assumption that the treatment effects follow a normal distribution. Recently proposed moment-based confidence intervals for the between-study variance are exact under the random effects model but are quite elaborate. Here, we present a much simpler method for calculating approximate confidence intervals of this type. This method uses variance-stabilising transformations as its basis and can be used for a very wide variety of moment-based estimators in both the random effects meta-analysis and meta-regression models.

  1. The effect of ratio and interval training on Pavlovian-instrumental transfer in mice.

    PubMed

    Wiltgen, Brian J; Sinclair, Courtney; Lane, Chadrick; Barrows, Frank; Molina, Martín; Chabanon-Hicks, Chloe

    2012-01-01

    Conditional stimuli (CS) that are paired with reward can be used to motivate instrumental responses. This process is called Pavlovian-instrumental transfer (PIT). A recent study in rats suggested that habitual responses are particularly sensitive to the motivational effects of reward cues. The current experiments examined this idea using ratio and interval training in mice. Two groups of animals were trained to lever press for food pellets that were delivered on random ratio or random interval schedules. Devaluation tests revealed that interval training led to habitual responding while ratio training produced goal-directed actions. The presentation of CSs paired with reward led to positive transfer in both groups, however, the size of this effect was much larger in mice that were trained on interval schedules. This result suggests that habitual responses are more sensitive to the motivational influence of reward cues than goal-directed actions. The implications for neurobiological models of motivation and drug seeking behaviors are discussed.

  2. Confidence Intervals for Squared Semipartial Correlation Coefficients: The Effect of Nonnormality

    ERIC Educational Resources Information Center

    Algina, James; Keselman, H. J.; Penfield, Randall D.

    2010-01-01

    The increase in the squared multiple correlation coefficient ([delta]R[superscript 2]) associated with a variable in a regression equation is a commonly used measure of importance in regression analysis. Algina, Keselman, and Penfield found that intervals based on asymptotic principles were typically very inaccurate, even though the sample size…

  3. Accuracy in Parameter Estimation for the Root Mean Square Error of Approximation: Sample Size Planning for Narrow Confidence Intervals

    ERIC Educational Resources Information Center

    Kelley, Ken; Lai, Keke

    2011-01-01

    The root mean square error of approximation (RMSEA) is one of the most widely reported measures of misfit/fit in applications of structural equation modeling. When the RMSEA is of interest, so too should be the accompanying confidence interval. A narrow confidence interval reveals that the plausible parameter values are confined to a relatively…

  4. The effect of US signalling and the US–CS interval on backward conditioning in mice

    PubMed Central

    Sanderson, David J.; Cuell, Steven F.; Bannerman, David M.

    2014-01-01

    The effect of US signalling and the US–CS interval in backward conditioning was assessed in mice. For one group of mice the presentation of food was signalled by a tone and for another group, food was unsignalled. For half of the mice, within each group, the presentation of food preceded a visual cue by 10 s. For the other half, food was presented at the start of the visual cue (0-s US–CS interval), resulting in simultaneous pairings of these events. A summation test and a subsequent retardation test were used to assess the inhibitory effects of backward conditioning in comparison to training with a non-reinforced visual cue that controlled for the possible effects of latent inhibition and conditioned inhibition caused as a consequence of differential conditioning. In the summation test unsignalled presentations of the US resulted in inhibition when the US–CS interval was 10 s, but not 0 s. Signalled presentations of the US resulted in inhibition, independent of the US–CS interval. In the retardation test, independent of US signalling, a US–CS interval of 10 s failed to result in inhibition, but an interval of 0 s resulted in greater conditioned responding to the backward CS than the control CS. A generalisation decrement account of the effect of signalling the US with a 0-s US–CS interval, which resulted in reduced responding in the summation test and faster acquisition in the retardation test, is discussed. PMID:25512678

  5. Effects of cocaine on performance under fixed-interval schedules with a small tandem ratio requirement.

    PubMed Central

    Pinkston, Jonathan W; Branch, Marc N

    2004-01-01

    Daily administration of cocaine often results in the development of tolerance to its effects on responding maintained by fixed-ratio schedules. Such effects have been observed to be greater when the ratio value is small, whereas less or no tolerance has been observed at large ratio values. Similar schedule-parameter-dependent tolerance, however, has not been observed with fixed-interval schedules arranging comparable interreinforcement intervals. This experiment examined the possibility that differences in rate and temporal patterning between the two types of schedule are responsible for the differences in observed patterns of tolerance. Five pigeons were trained to key peck on a three-component multiple (tandem fixed-interval fixed-ratio) schedule. The interval values were 10, 30, and 120 s; the tandem ratio was held constant at five responses. Performance appeared more like that observed under fixed-ratio schedules than fixed-interval schedules. Effects of various doses of cocaine given weekly were then determined for each pigeon. A dose that reduced responding was administered prior to each session for 50 days. A reassessment of effects of the range of doses revealed tolerance. The degree of tolerance was similar across components of the multiple schedule. Next, the saline vehicle was administered prior to each session for 50 days to assess the persistence of tolerance. Tolerance diminished in all subjects. Overall, the results suggested that schedule-parameter-dependent tolerance does not depend on the temporal pattern of responding engendered by fixed-ratio schedules. PMID:15693524

  6. Constraints on Infants' Musical Rhythm Perception: Effects of Interval Ratio Complexity and Enculturation

    ERIC Educational Resources Information Center

    Hannon, Erin E.; Soley, Gaye; Levine, Rachel S.

    2011-01-01

    Effects of culture-specific experience on musical rhythm perception are evident by 12 months of age, but the role of culture-general rhythm processing constraints during early infancy has not been explored. Using a habituation procedure with 5- and 7-month-old infants, we investigated effects of temporal interval ratio complexity on discrimination…

  7. Comparison of Approaches to Constructing Confidence Intervals for Mediating Effects Using Structural Equation Models

    ERIC Educational Resources Information Center

    Cheung, Mike W. L.

    2007-01-01

    Mediators are variables that explain the association between an independent variable and a dependent variable. Structural equation modeling (SEM) is widely used to test models with mediating effects. This article illustrates how to construct confidence intervals (CIs) of the mediating effects for a variety of models in SEM. Specifically, mediating…

  8. Effects of intensity and duration in aerobic high-intensity interval training in highly trained junior cross-country skiers.

    PubMed

    Sandbakk, Øyvind; Sandbakk, Silvana B; Ettema, Gertjan; Welde, Boye

    2013-07-01

    The purpose of this study was to test whether a long duration of aerobic high-intensity interval training is more effective than shorter intervals at a higher intensity in highly trained endurance athletes. The sample comprised of 12 male and 9 female, national-level, junior cross-country skiers (age, 17.5 ± 0.4 years, maximal oxygen uptake (V[Combining Dot Above]O2max): 67.4 ± 7.7 ml min kg), who performed 8-week baseline and 8-week intervention training periods on dry land. During the intervention period, a short-interval group (SIG, n = 7) added 2 weekly sessions with short duration intervals (2- to 4-minute bouts, total duration of 15-20 minutes), a long-interval group (LIG; n = 7) added 2 weekly sessions with long duration intervals (5- to 10-minute bouts, total duration of 40-45 minutes). The interval sessions were performed with the athletes' maximal sustainable intensity. A control group (CG; n = 7) added 2 weekly sessions with low-intensity endurance training at 65-74% of maximal heart rate. Before and after the intervention period, the skiers were tested for time-trial performance on 12-km roller-ski skating and 7-km hill run. V[Combining Dot Above]O2max and oxygen uptake at the ventilatory threshold (V[Combining Dot Above]O2VT) were measured during treadmill running. After the intervention training period, the LIG-improved 12-km roller ski, 7-km hill run, V[Combining Dot Above]O2max, and V[Combining Dot Above]O2VT by 6.8 ± 4.0%, 4.8 ± 2.6%, 3.7 ± 1.6%, and 5.8 ± 3.3%, respectively, from pre- to posttesting, and improved both performance tests and V[Combining Dot Above]O2VT when compared with the SIG and the CG (all p < 0.05). The SIG improved V[Combining Dot Above]O2max by 3.5 ± 3.2% from pre- to posttesting (p < 0.05), whereas the CG remained unchanged. As hypothesized, a long duration of aerobic high-intensity interval training improved endurance performance and oxygen uptake at the ventilatory threshold more than shorter intervals at a higher

  9. The effect of a brief sprint interval exercise on growth factors and inflammatory mediators.

    PubMed

    Meckel, Yoav; Eliakim, Alon; Seraev, Mariana; Zaldivar, Frank; Cooper, Dan M; Sagiv, Michael; Nemet, Dan

    2009-01-01

    Exercise training efficiency depends on the intensity, volume, duration, and frequency of training, as well as on the athlete's ability to tolerate it. Recent efforts to quantify the effects of aerobic exercise training on hormonal response have suggested that exercise leads to simultaneous changes of antagonistic mediators. The effects of anaerobic exercise on these mediators are not known. Therefore, the aim of the present study was to evaluate the effects of a brief sprint interval session on the balance between anabolic (growth hormone [GH]--> insulin-like growth factor [IGF]-I axis) and catabolic hormones (cortisol), and circulating inflammatory cytokines such as interleukin (IL)-6. Twelve healthy elite junior handball players (17-20 years) participated in the study. Exercise consisted of a 4 x 250-m run on a treadmill, at a constant intensity of 80% of the personal maximal speed. Each run was separated by 3 minutes of rest. Blood samples were collected before, immediately after each 250-m run, and 1 hour after the last run. Exercise led to significant increases in GH (0.3 +/- 0.2 to 5.1 +/- 2.2 ngxml, p < 0.05), IGF binding protein (IGFBP)-3 (4191 +/- 2.48 to 4875 +/- 301 ngxml, p < 0.05), IL-6 (1.3 +/- 0.2 to 2.1 +/- 0.3 pgxml, p < 0.002), testosterone, and testosterone/cortisol ratio, and to a significant decrease in IGFBP-1 levels. Levels of IL-6 remained elevated 1 hour after the end of exercise. Exercise had no significant effects on IGF-I and cortisol levels. Changes in the GH-IGF-I axis and testosterone/cortisol ratio after the brief sprint interval exercise suggested exercise-related anabolic adaptations. The increase in IL-6 may indicate its important role in muscle tissue repair after anaerobic exercise. Changes in the anabolic-catabolic hormonal balance and in inflammatory mediators can be used as an objective tool to gauge the training intensity of different types of anaerobic exercises and training periods.

  10. Effect of tapered normal and interval training on performance of Standardbred pacers.

    PubMed

    Shearman, J P; Hamlin, M J; Hopkins, W G

    2002-07-01

    Human athletes taper or reduce their training load before a race to enhance performance, apparently because recovery from the effects of fatigue occurs faster than the loss of fitness from the reduced training. However, there appear to be no previous studies of tapering of equine athletes. Our aim in the present study was, therefore, to investigate the efficacy of tapering with Standardbred pacers. We determined the effect of repeated cycles of tapered training on performance of Standardbred pacers. After 8 weeks of jogging and 3 x 2 week cycles of pace work, 19 horses were randomised to a taper and a control group. The taper group completed 5 consecutive 2 week cycles, each incorporating a 7 day taper; some cycles included high-intensity interval training. The control group continued with 5 more cycles of pace work. All horses completed a 2400 m individual time trial after each cycle. Peak and mean speed of the taper group were faster than those of the control group in all cycles; the differences were clear-cut in all cycles for peak speed (overall 4.4%, 95% confidence interval 1.7 to 7.1%), but only in one of the interval-training cycles for mean speed (2.4%, 0.3 to 4.7%). Four horses in the taper group were injured during interval training. Repeated tapering produces a worthwhile enhancement of performance in Standardbreds, but the addition of interval training appears to increase the risk of injury. PMID:12117113

  11. Effects of acute sprint interval cycling and energy replacement on postprandial lipemia.

    PubMed

    Freese, Eric C; Levine, Ari S; Chapman, Donald P; Hausman, Dorothy B; Cureton, Kirk J

    2011-12-01

    High postprandial blood triglyceride (TG) levels increase cardiovascular disease risk. Exercise interventions may be effective in reducing postprandial blood TG. The purpose of this study was to determine the effects of sprint interval cycling (SIC), with and without replacement of the energy deficit, on postprandial lipemia. In a repeated-measures crossover design, six men and six women participated in three trials, each taking place over 2 days. On the evening of the first day of each trial, the participants either did SIC without replacing the energy deficit (Ex-Def), did SIC and replaced the energy deficit (Ex-Bal), or did not exercise (control). SIC was performed on a cycle ergometer and involved four 30-s all-out sprints with 4-min active recovery. In the morning of day 2, responses to a high-fat meal were measured. Venous blood samples were collected in the fasted state and at 0, 30, 60, 120, and 180 min postprandial. There was a trend toward a reduction with treatment in fasting TG (P = 0.068), but no significant treatment effect for fasting insulin, glucose, nonesterified fatty acids, or betahydroxybutryrate (P > 0.05). The postprandial area under the curve (mmol·l(-1)·3 h(-1)) TG response was significantly lower in Ex-Def (21%, P = 0.006) and Ex-Bal (10%, P = 0.044) than in control, and significantly lower in Ex-Def (12%, P = 0.032) than in Ex-Bal. There was no treatment effect (P > 0.05) observed for area under the curve responses of insulin, glucose, nonesterified fatty acids, or betahydroxybutryrate. SIC reduces postprandial lipemia, but the energy deficit alone does not fully explain the decrease observed.

  12. Making Subjective Judgments in Quantitative Studies: The Importance of Using Effect Sizes and Confidence Intervals

    ERIC Educational Resources Information Center

    Callahan, Jamie L.; Reio, Thomas G., Jr.

    2006-01-01

    At least twenty-three journals in the social sciences purportedly require authors to report effect sizes and, to a much lesser extent, confidence intervals; yet these requirements are rarely clear in the information for contributors. This article reviews some of the literature criticizing the exclusive use of null hypothesis significance testing…

  13. Conceptual and Practical Implications for Rehabilitation Research: Effect Size Estimates, Confidence Intervals, and Power

    ERIC Educational Resources Information Center

    Ferrin, James M.; Bishop, Malachy; Tansey, Timothy N.; Frain, Michael; Swett, Elizabeth A.; Lane, Frank J.

    2007-01-01

    For a number of conceptually and practically important reasons, reporting of effect size estimates, confidence intervals, and power in parameter estimation is increasingly being recognized as the preferred approach in social science research. Unfortunately, this practice has not yet been widely adopted in the rehabilitation or general counseling…

  14. A Note on Confidence Intervals for Two-Group Latent Mean Effect Size Measures

    ERIC Educational Resources Information Center

    Choi, Jaehwa; Fan, Weihua; Hancock, Gregory R.

    2009-01-01

    This note suggests delta method implementations for deriving confidence intervals for a latent mean effect size measure for the case of 2 independent populations. A hypothetical kindergarten reading example using these implementations is provided, as is supporting LISREL syntax. (Contains 1 table.)

  15. Effect of preseason concurrent muscular strength and high-intensity interval training in professional soccer players.

    PubMed

    Wong, Pui-lam; Chaouachi, Anis; Chamari, Karim; Dellal, Alexandre; Wisloff, Ulrik

    2010-03-01

    This study examined the effect of concurrent muscular strength and high-intensity running interval training on professional soccer players' explosive performances and aerobic endurance. Thirty-nine players participated in the study, where both the experimental group (EG, n = 20) and control group (CG, n = 19) participated in 8 weeks of regular soccer training, with the EG receiving additional muscular strength and high-intensity interval training twice per week throughout. Muscular strength training consisted of 4 sets of 6RM (repetition maximum) of high-pull, jump squat, bench press, back half squat, and chin-up exercises. The high-intensity interval training consisted of 16 intervals each of 15-second sprints at 120% of individual maximal aerobic speed interspersed with 15 seconds of rest. EG significantly increased (p < or = 0.05) 1RM back half squat and bench press but showed no changes in body mass. Within-subject improvement was significantly higher (p < or = 0.01) in the EG compared with the CG for vertical jump height, 10-m and 30-m sprint times, distances covered in the Yo-Yo Intermittent Recovery Test and maximal aerobic speed test, and maximal aerobic speed. High-intensity interval running can be concurrently performed with high load muscular strength training to enhance soccer players' explosive performances and aerobic endurance.

  16. Bouts of responding on variable-interval schedules: effects of deprivation level.

    PubMed Central

    Shull, Richard L

    2004-01-01

    Rats obtained food pellets on a variable-interval schedule of reinforcement by nose poking a lighted key. After training to establish baseline performance (with the mean variable interval set at either 60, 120, or 240 s), the rats were given free access to food during the hour just before their daily session. This satiation operation reduced the rate of key poking. Analysis of the interresponse time distributions (log survivor plots) indicated that key poking occurred in bouts. Prefeeding lengthened the pauses between bouts, shortened the length of bouts (less reliably), and had a relatively small decremental effect on the response rate within bouts. That deprivation level affects mainly between-bout pauses has been reported previously with fixed-ratio schedules. Thus, when the focus is on bouts, the performances maintained by variable-interval schedules and fixed-ratio schedules are similarly affected by deprivation. PMID:15239490

  17. Effect of interrepetition rest intervals on weight training repetition power output.

    PubMed

    Lawton, Trent W; Cronin, John B; Lindsell, Rod P

    2006-02-01

    The purpose of this study was to determine the change in weight training repetition power output as a consequence of interrepetition rest intervals. Twenty-six elite junior male basketball and soccer players performed bench presses using a 6 repetition maximum (6RM) load. The power output for each repetition was recorded using a linear encoder sampling each 10 ms (100 Hz). Subjects were assigned to 1 of 3 intervention groups, differentiated by the arrangement of rest intervals within the 6 repetitions: 6 x 1 repetition with 20-second rest periods between each repetition (Singles); 3 x 2 repetitions with 50 seconds between each pair of repetitions (Doubles); or 2 x 3 repetitions with 100 seconds of rest between each 3 repetitions (Triples). A timer was used to ensure that the rest interval and duration to complete all interrepetition interventions was equated across groups (118 seconds). Significantly (p < 0.05) greater repetition power outputs (25-49%) were observed in the later repetitions (4-6) of the Singles, Doubles, and Triples loading schemes. Significantly greater total power output (21.6-25.1%) was observed for all interrepetition rest interventions when compared to traditional continuous 6RM total power output. No significant between-group differences were found (p = 0.96). We conclude that utilizing interrepetition rest intervals enables greater repetition and total power output in comparison to traditional loading parameters.

  18. The effects of initial interval size on the efficacy of DRO schedules of reinforcement.

    PubMed

    Repp, A C; Felce, D; Barton, L E

    1991-01-01

    The differential reinforcement of other behavior (DRO) is a behavior-reduction procedure that has been popular for several years. In classroom settings, it provides reinforcement when a student does not display inappropriate responding for a particular interval of time. Unfortunately, relatively little is known about how to use DRO effectively in applied settings. Most research has been conducted in laboratory settings; the purpose of the present study was to provide a replication of one of those studies. This study examined the effect of the size of the initial DRO interval on the disruptive behavior of students with moderate disabilities. In the first experiment, a group of six students was observed during baseline in two classes. Two different DRO values were then used. In one classroom, it was equal to the mean number of 10-second intervals between disruptions during baseline. In the other classroom, it was twice the mean number during baseline. In the final phase, behavior in both classrooms was put under the same DRO program. In the second experiment, the disruptive behavior of three students was studied in a different design in which both methods of determining the initial DRO value were compared. The results of both experiments showed that an initial DRO value equal to the mean number of intervals between responses in baseline was much more effective than a value twice that size in reducing disruptions. PMID:2022233

  19. The effects of initial interval size on the efficacy of DRO schedules of reinforcement.

    PubMed

    Repp, A C; Felce, D; Barton, L E

    1991-01-01

    The differential reinforcement of other behavior (DRO) is a behavior-reduction procedure that has been popular for several years. In classroom settings, it provides reinforcement when a student does not display inappropriate responding for a particular interval of time. Unfortunately, relatively little is known about how to use DRO effectively in applied settings. Most research has been conducted in laboratory settings; the purpose of the present study was to provide a replication of one of those studies. This study examined the effect of the size of the initial DRO interval on the disruptive behavior of students with moderate disabilities. In the first experiment, a group of six students was observed during baseline in two classes. Two different DRO values were then used. In one classroom, it was equal to the mean number of 10-second intervals between disruptions during baseline. In the other classroom, it was twice the mean number during baseline. In the final phase, behavior in both classrooms was put under the same DRO program. In the second experiment, the disruptive behavior of three students was studied in a different design in which both methods of determining the initial DRO value were compared. The results of both experiments showed that an initial DRO value equal to the mean number of intervals between responses in baseline was much more effective than a value twice that size in reducing disruptions.

  20. The effect of high intensity interval exercise on postprandial triacylglycerol and leukocyte activation--monitored for 48 h post exercise.

    PubMed

    Gabriel, Brendan Morris; Pugh, Jamie; Pruneta-Deloche, Valerie; Moulin, Philippe; Ratkevicius, Aivaras; Gray, Stuart Robert

    2013-01-01

    Postprandial phenomenon are thought to contribute to atherogenesis alongside activation of the immune system. A single bout of high intensity interval exercise attenuates postprandial triacylglycerol (TG), although the longevity and mechanisms underlying this observation are unknown. The aims of this study were to determine whether this attenuation in postprandial TG remained 2 days after high intensity interval exercise, to monitor markers of leukocyte activation and investigate the underlying mechanisms. Eight young men each completed two three day trials. On day 1: subjects rested (Control) or performed 5 x 30 s maximal sprints (high intensity interval exercise). On day 2 and 3 subjects consumed high fat meals for breakfast and 3 h later for lunch. Blood samples were taken at various times and analysed for TG, glucose and TG-rich lipoprotein (TRL)-bound LPL-dependent TRL-TG hydrolysis (LTTH). Flow cytometry was used to evaluate granulocyte, monocyte and lymphocyte CD11b and CD36 expression. On day 2 after high intensity interval exercise TG area under the curve was lower (P<0.05) (7.46 ± 1.53 mmol/l/7h) compared to the control trial (9.47 ± 3 .04 mmol/l/7h) with no differences during day 3 of the trial. LTTH activity was higher (P<0.05) after high intensity interval exercise, at 2 hours of day 2, compared to control. Granulocyte, monocyte and lymphocyte CD11b expression increased with time over day 2 and 3 of the study (P<0.0001). Lymphocyte and monocyte CD36 expression decreased with time over day 2 and 3 (P<0.05). There were no differences between trials in CD11b and CD36 expression on any leukocytes. A single session of high intensity interval exercise attenuated postprandial TG on day 2 of the study, with this effect abolished by day 3.The reduction in postprandial TG was associated with an increase in LTTH. High intensity interval exercise had no effect on postprandial responses of CD11b or CD36.

  1. Effects of Short-Interval and Long-Interval Swimming Protocols on Performance, Aerobic Adaptations, and Technical Parameters: A Training Study.

    PubMed

    Dalamitros, Athanasios A; Zafeiridis, Andreas S; Toubekis, Argyris G; Tsalis, George A; Pelarigo, Jailton G; Manou, Vasiliki; Kellis, Spiridon

    2016-10-01

    Dalamitros, AA, Zafeiridis, AS, Toubekis, AG, Tsalis, GA, Pelarigo, JG, Manou, V, and Kellis, S. Effects of short-interval and long-interval swimming protocols on performance, aerobic adaptations, and technical parameters: A training study. J Strength Cond Res 30(10): 2871-2879, 2016-This study compared 2-interval swimming training programs of different work interval durations, matched for total distance and exercise intensity, on swimming performance, aerobic adaptations, and technical parameters. Twenty-four former swimmers were equally divided to short-interval training group (INT50, 12-16 × 50 m with 15 seconds rest), long-interval training group (INT100, 6-8 × 100 m with 30 seconds rest), and a control group (CON). The 2 experimental groups followed the specified swimming training program for 8 weeks. Before and after training, swimming performance, technical parameters, and indices of aerobic adaptations were assessed. ΙΝΤ50 and ΙΝΤ100 improved swimming performance in 100 and 400-m tests and the maximal aerobic speed (p ≤ 0.05); the performance in the 50-m swim did not change. Posttraining V[Combining Dot Above]O2max values were higher compared with pretraining values in both training groups (p ≤ 0.05), whereas peak aerobic power output increased only in INT100 (p ≤ 0.05). The 1-minute heart rate and blood lactate recovery values decreased after training in both groups (p < 0.01). Stroke length increased in 100 and 400-m swimming tests after training in both groups (p ≤ 0.05); no changes were observed in stroke rate after training. Comparisons between groups on posttraining mean values, after adjusting for pretraining values, revealed no significant differences between ΙΝΤ50 and ΙΝΤ100 for all variables; however, all measures were improved vs. the respective values in the CON (p < 0.001-0.05). In conclusion, when matched for distance and exercise intensity, the short-interval (50 m) and long-interval (100 m) protocols confer analogous

  2. Outcome pre- and postexposure effects: retention interval interacts with primacy and recency.

    PubMed

    Urushihara, Kouji; Wheeler, Daniel S; Miller, Ralph R

    2004-10-01

    Effects of outcome-alone pretraining and posttraining exposure were investigated in conditioned suppression experiments conducted within a sensory preconditioning preparation with rats. Experiment 1 found that interference by outcome postexposure was stronger than that by outcome preexposure, suggesting a recency effect. Experiment 2 found that after a long retention interval, outcome preexposure produced more interference than outcome postexposure, suggesting a shift from recency to primacy with increasing retention interval. Experiment 3 showed that presentation of a priming stimulus that had been embedded within the earlier phase of treatment also caused a shift from recency to primacy. These results suggest that, at least in a sensory preconditioning paradigm, retrievability of outcome-alone exposure memory is an important determinant of any outcome-alone exposure effect.

  3. Conditional-sampling schemes for turbulent flow, based on the variable-interval time averaging (VITA) algorithm

    NASA Astrophysics Data System (ADS)

    Morrison, J. F.; Tsai, H. M.; Bradshaw, P.

    1988-12-01

    The variable-interval time-averaging (“VITA”) algorithm has been tested in a variety of turbulent boundary layers for its ability to detect shear-stress-producing motions from hot-wire signals. A “VITA + LEVEL” scheme (which uses criteria for both short-time variance and short-time average, i.e.“level”) has been devised, and used in several different boundary layers. This scheme yields length-scale statistics that are acceptably independent of the conditioning criteria, which the VITA scheme does not.

  4. Conditional-sampling schemes for turbulent flow, based on the variable-interval time averaging (VITA) algorithm

    NASA Astrophysics Data System (ADS)

    Morrison, J. F.; Tsai, H. M.; Bradshaw, P.

    The variable-interval time-averaging ('VITA') algorithm has been tested in a variety of turbulent boundary layers for its ability to detect shear-stress-producing motions from hot-wire signals. A 'VITA+LEVEL' scheme (which uses criteria for both short-time variance and short-time average, i.e., 'level') has been devised, and used in several different boundary layers. This scheme yields length-scale statistics that are acceptably independent of the conditioning criteria, which the VITA scheme does not.

  5. Assessing the effects of intermediate variables on birth interval-specific measures of fertility.

    PubMed

    Palloni, A

    1984-01-01

    This paper proposes a technique to simultaneously assess the effect of selected intermediate variables on the dynamics of birth intervals and to aggregate such effects across births of different order. The essentials, virtues and limitations of other approaches are 1st summarized. A method to link measures of birth interval dynamics to aggregated measures of fertility such as the age-specific fertility rates and total fertility is explained. A set of operations is suggested, required to translate estimates of birth interval-specific effects of intermediate variables into aggregate effects (e.g., effects at the level of fertility rates). These operations effectively permit the synthesis of results from multivariate procedures and those of techniques aimed at decomposing the effects of intermediate variables. Discussed are estimation and measurement procedures to deal with deal available from retrospective interviews carried out as part of the World Fertility Survey (WFS) program. The effects of marriage pattern are not considered. The effects of lactation are measured by using a dichotomous variable with a value of 1 if the preceding child was breast fed for at least as long as 9 months less than the beginning of the segment of interest and 0 otherwise. Following the assignment of a measure of effectiveness, 3 groups are distinguished in measuring contraceptive use: non-contraceptors, those using an ineffective method, and effective contraceptors. With respect to measuring the effects of induced abortion and spontaneous fetal losses, a variable is created indicating whether or not a birth leading to a fetal loss or the fetal loss itself had occurred within the segment being examined. 2 indicators, 1 a binary variable and the other aimed at measuring gradations of sterility are introduced to measure exposure to intercourse and sterility. Logit regression coefficients for selected intermediate variables are presented for Peru. The tables reveal the power of the

  6. The Effects of Intermittent Exercise on Physiological Outcomes in an Obese Population: Continuous Versus Interval Walking

    PubMed Central

    Campbell, Leanne; Wallman, Karen; Green, Danny

    2010-01-01

    This study compared the effects of 12 weeks of caloric restriction and interval exercise (INT) and caloric restriction and continuous aerobic exercise (CON) on physiological outcomes in an obese population. Forty-four individuals (BMI ≥ 30 kg·m-2) were randomised into the INT or CON group. Participant withdrawal resulted in 12 and 14 participants in the INT and CON groups, respectively. All participants were on a strict monitored diet. Exercise involved two 15-min bouts of walking performed on five days per week. Interval exercise consisted of a 2:1 min ratio of low-intensity (40-45% VO2peak) and high- intensity (70-75% VO2peak) exercise, while the CON group exercised between 50-55% VO2peak. Exercise duration and average intensity (%VO2peak) were similar between groups. There were no significant differences (p > 0.05) between the two groups for any variable assessed apart from very low density lipoprotein (VLDL-C), which significantly decreased over time in the INT group only (p < 0.05, d = 1.03). Caloric restriction and interval exercise compared to caloric restriction and continuous aerobic exercise resulted in similar outcome measures apart from VLDL-C levels, which significantly improved in the INT group only. Key points Twelve weeks of interval exercise and caloric restriction resulted in significant improvement in very low density lipoprotein cholesterol in an obese population, as compared to continuous aerobic exercise and caloric restriction. Twelve weeks of either interval exercise or continuous exercise resulted in similar improvements in aerobic fitness in an obese population. PMID:24149382

  7. Effective sample size: Quick estimation of the effect of related samples in genetic case-control association analyses.

    PubMed

    Yang, Yaning; Remmers, Elaine F; Ogunwole, Chukwuma B; Kastner, Daniel L; Gregersen, Peter K; Li, Wentian

    2011-02-01

    Affected relatives are essential for pedigree linkage analysis, however, they cause a violation of the independent sample assumption in case-control association studies. To avoid the correlation between samples, a common practice is to take only one affected sample per pedigree in association analysis. Although several methods exist in handling correlated samples, they are still not widely used in part because these are not easily implemented, or because they are not widely known. We advocate the effective sample size method as a simple and accessible approach for case-control association analysis with correlated samples. This method modifies the chi-square test statistic, p-value, and 95% confidence interval of the odds-ratio by replacing the apparent number of allele or genotype counts with the effective ones in the standard formula, without the need for specialized computer programs. We present a simple formula for calculating effective sample size for many types of relative pairs and relative sets. For allele frequency estimation, the effective sample size method captures the variance inflation exactly. For genotype frequency, simulations showed that effective sample size provides a satisfactory approximation. A gene which is previously identified as a type 1 diabetes susceptibility locus, the interferon-induced helicase gene (IFIH1), is shown to be significantly associated with rheumatoid arthritis when the effective sample size method is applied. This significant association is not established if only one affected sib per pedigree were used in the association analysis. Relationship between the effective sample size method and other methods - the generalized estimation equation, variance of eigenvalues for correlation matrices, and genomic controls - are discussed.

  8. Effective Sample Size: Quick Estimation of the Effect of Related Samples in Genetic Case-Control Association Analyses

    PubMed Central

    Yang, Yaning; Remmers, Elaine F.; Ogunwole, Chukwuma B.; Kastner, Daniel L.; Gregersen, Peter K.; Li, Wentian

    2011-01-01

    Summary Affected relatives are essential for pedigree linkage analysis, however, they cause a violation of the independent sample assumption in case-control association studies. To avoid the correlation between samples, a common practice is to take only one affected sample per pedigree in association analysis. Although several methods exist in handling correlated samples, they are still not widely used in part because these are not easily implemented, or because they are not widely known. We advocate the effective sample size method as a simple and accessible approach for case-control association analysis with correlated samples. This method modifies the chi-square test statistic, p-value, and 95% confidence interval of the odds-ratio by replacing the apparent number of allele or genotype counts with the effective ones in the standard formula, without the need for specialized computer programs. We present a simple formula for calculating effective sample size for many types of relative pairs and relative sets. For allele frequency estimation, the effective sample size method captures the variance inflation exactly. For genotype frequency, simulations showed that effective sample size provides a satisfactory approximation. A gene which is previously identified as a type 1 diabetes susceptibility locus, the interferon-induced helicase gene (IFIH1), is shown to be significantly associated with rheumatoid arthritis when the effective sample size method is applied. This significant association is not established if only one affected sib per pedigree were used in the association analysis. Relationship between the effective sample size method and other methods – the generalized estimation equation, variance of eigenvalues for correlation matrices, and genomic controls – are discussed. PMID:21333602

  9. Effective sample size: Quick estimation of the effect of related samples in genetic case-control association analyses.

    PubMed

    Yang, Yaning; Remmers, Elaine F; Ogunwole, Chukwuma B; Kastner, Daniel L; Gregersen, Peter K; Li, Wentian

    2011-02-01

    Affected relatives are essential for pedigree linkage analysis, however, they cause a violation of the independent sample assumption in case-control association studies. To avoid the correlation between samples, a common practice is to take only one affected sample per pedigree in association analysis. Although several methods exist in handling correlated samples, they are still not widely used in part because these are not easily implemented, or because they are not widely known. We advocate the effective sample size method as a simple and accessible approach for case-control association analysis with correlated samples. This method modifies the chi-square test statistic, p-value, and 95% confidence interval of the odds-ratio by replacing the apparent number of allele or genotype counts with the effective ones in the standard formula, without the need for specialized computer programs. We present a simple formula for calculating effective sample size for many types of relative pairs and relative sets. For allele frequency estimation, the effective sample size method captures the variance inflation exactly. For genotype frequency, simulations showed that effective sample size provides a satisfactory approximation. A gene which is previously identified as a type 1 diabetes susceptibility locus, the interferon-induced helicase gene (IFIH1), is shown to be significantly associated with rheumatoid arthritis when the effective sample size method is applied. This significant association is not established if only one affected sib per pedigree were used in the association analysis. Relationship between the effective sample size method and other methods - the generalized estimation equation, variance of eigenvalues for correlation matrices, and genomic controls - are discussed. PMID:21333602

  10. Effects of supplemental feeding interval on adult cows in western Texas.

    PubMed

    Huston, J E; Lippke, H; Forbes, T D; Holloway, J W; Machen, R V

    1999-11-01

    Two experiments involving Brangus and Hereford x Brangus cows (3 to 10 yr) were conducted at four locations in western Texas to determine the effects of supplemental feeding interval on serum urea nitrogen (SUN) patterns, intake of supplement and forage, and winter changes in live body weight and condition score. Treatments were control (Control; no supplemental feed) and the equivalent of .91 kg/d of cottonseed meal (CSM) fed daily (Daily), three times per week (3T/WK), or one time per week (WK). At each location, one pasture group was given all four treatments (four cows/treatment) using Calan gates. In Exp. 1, conducted in 1994-95, blood samples were obtained for determining SUN during the last week of the study. Experiment 2, conducted in 1995-96, included both an individually fed herd and four additional herds at each location that were group-fed the four treatments. Experiment 2 included estimates of intakes of both CSM and forage in both individually fed and group-fed herds. A bolus containing chromium (Cr-bolus) was used to estimate fecal output in the individually fed cows. A double marker technique was used to determine total (Cr-bolus) and CSM (Yb) intakes in the group-fed cows. Data included initial and final cow weights and condition scores (Exp. 1 and 2), SUN patterns (Exp. 1), and supplement, forage, and total intakes (Exp. 2). Feeding CSM to range cows increased SUN concentrations (Exp. 1), reduced losses in live body weight and body condition score (Exp. 1 and 2), and tended to decrease forage intake by the approximate amount of the supplement (Exp. 2). Generally, providing supplement as infrequently as once per week reduced losses in live body weight and body condition score compared with control and was as effective as once daily supplementation. For the group-fed cows, supplement intake, forage intake, and live body weight change were more variable within groups with once daily feeding than when supplement was fed less frequently. These data

  11. High-intensity interval training has positive effects on performance in ice hockey players.

    PubMed

    Naimo, M A; de Souza, E O; Wilson, J M; Carpenter, A L; Gilchrist, P; Lowery, R P; Averbuch, B; White, T M; Joy, J

    2015-01-01

    In spite of the well-known benefits that have been shown, few studies have looked at the practical applications of high-intensity interval training (HIIT) on athletic performance. This study investigated the effects of a HIIT program compared to traditional continuous endurance exercise training. 24 hockey players were randomly assigned to either a continuous or high-intensity interval group during a 4-week training program. The interval group (IG) was involved in a periodized HIIT program. The continuous group (CG) performed moderate intensity cycling for 45-60 min at an intensity that was 65% of their calculated heart rate reserve. Body composition, muscle thickness, anaerobic power, and on-ice measures were assessed pre- and post-training. Muscle thickness was significantly greater in IG (p=0.01) when compared to CG. The IG had greater values for both ∆ peak power (p<0.003) and ∆ mean power (p<0.02). Additionally, IG demonstrated a faster ∆ sprint (p<0.02) and a trend (p=0.08) for faster ∆ endurance test time to completion for IG. These results indicate that hockey players may utilize short-term HIIT to elicit positive effects in muscle thickness, power and on-ice performance.

  12. Effect of alfaprostol, lasalocid, and once-daily suckling on postpartum interval in Brahman and Brahman crossbred cattle.

    PubMed

    Del Vecchio, R P; Randel, R D; Neuendorff, D A; Peterson, L A

    1988-10-01

    Brahman cows (n = 49) and primiparous heifers (n = 11), Brahman x Hereford primiparous F1 heifers (n = 86) and Simmental x Brahman primiparous F1 heifers (n = 13) were randomly allotted by breed, age and date of calving to one of eight treatment groups: 1) control; 2) once-daily suckling; 3) lasalocid (200 mg/hd/d); 4) alfaprostol (5 mg intermuscular injections on Days 21 and 32 post partum); 5) lasalocid + once-daily suckling; 6) alfaprostol + once daily suckling; 7) alfaprostol + lasalocid; 8) alfaprostol + lasalocid + once daily suckling. All animals received 2.3 kg/hd/d of a concentrate (6 corn : 1 cottonseed meal) and lasalocid was mixed and fed in the concentrate. Body weights and condition scores were taken on Day 1 post partum and every 28 d thereafter. All animals were maintained with sterile marker bulls with Brahman and Simmental x Brahman cattle artificially inseminated at first estrus. Blood samples were collected at weekly intervals starting on Day 21 post partum until estrus and at nine to twelve days post estrus when the ovaries were palpated for corpora lutea. After the first postpartum estrus with a corpora lutea, cows were placed with fertile bulls. Mean serum progesterone concentrations were below 0.5 ng/ml prior to treatment. Calf weight gains to 90 d were not affected by age (P > 0.10) but were lower in the once-daily suckling group (P < 0.05). Treatment did not affect cow weight or condition score (P > 0.10). Cows had a shorter postpartum interval (P < 0.0001) than heifers. Once-daily suckling shortened postpartum interval (P < 0.0001) and positively influenced the cumulative frequency of return to estrus by 40 d post partum (P < 0.02). Alfaprostol did not affect postpartum interval (P > 0.10) but did increase the cumulative frequency of return to estrus by 90 d post partum (P < 0.03). Lasalocid did not affect postpartum interval or cumulative frequency of return to estrus (P > 0.10). Both once-daily suckling and alfaprostol were effective in

  13. Effect of alfaprostol, lasalocid, and once-daily suckling on postpartum interval in Brahman and Brahman crossbred cattle.

    PubMed

    Del Vecchio, R P; Randel, R D; Neuendorff, D A; Peterson, L A

    1988-10-01

    Brahman cows (n = 49) and primiparous heifers (n = 11), Brahman x Hereford primiparous F1 heifers (n = 86) and Simmental x Brahman primiparous F1 heifers (n = 13) were randomly allotted by breed, age and date of calving to one of eight treatment groups: 1) control; 2) once-daily suckling; 3) lasalocid (200 mg/hd/d); 4) alfaprostol (5 mg intermuscular injections on Days 21 and 32 post partum); 5) lasalocid + once-daily suckling; 6) alfaprostol + once daily suckling; 7) alfaprostol + lasalocid; 8) alfaprostol + lasalocid + once daily suckling. All animals received 2.3 kg/hd/d of a concentrate (6 corn : 1 cottonseed meal) and lasalocid was mixed and fed in the concentrate. Body weights and condition scores were taken on Day 1 post partum and every 28 d thereafter. All animals were maintained with sterile marker bulls with Brahman and Simmental x Brahman cattle artificially inseminated at first estrus. Blood samples were collected at weekly intervals starting on Day 21 post partum until estrus and at nine to twelve days post estrus when the ovaries were palpated for corpora lutea. After the first postpartum estrus with a corpora lutea, cows were placed with fertile bulls. Mean serum progesterone concentrations were below 0.5 ng/ml prior to treatment. Calf weight gains to 90 d were not affected by age (P > 0.10) but were lower in the once-daily suckling group (P < 0.05). Treatment did not affect cow weight or condition score (P > 0.10). Cows had a shorter postpartum interval (P < 0.0001) than heifers. Once-daily suckling shortened postpartum interval (P < 0.0001) and positively influenced the cumulative frequency of return to estrus by 40 d post partum (P < 0.02). Alfaprostol did not affect postpartum interval (P > 0.10) but did increase the cumulative frequency of return to estrus by 90 d post partum (P < 0.03). Lasalocid did not affect postpartum interval or cumulative frequency of return to estrus (P > 0.10). Both once-daily suckling and alfaprostol were effective in

  14. Effect of treadmill walking on the stride interval dynamics of human gait.

    PubMed

    Chang, Matthew D; Shaikh, Sameer; Chau, Tom

    2009-11-01

    Metronomic walking has been found to diminish the statistical persistence intrinsic to the stride interval time series of human gait. Since treadmill walking (TW) possesses a similar form of external pacing, we proposed to study the disruptions in the natural neuromuscular rhythms of gait during TW. Treadmill walking is a widespread rehabilitative tool, however, its effect on an individual's stride dynamics is not well understood. To better elucidate potential effects, we tested the hypothesis that TW without handrails would diminish the statistical persistence in an individual's stride interval time series. The scaling exponent (alpha) was employed in this study as a measure of the statistical persistence of the stride interval time series. Sixteen able-bodied young adults (mean age: 23.3+/-3.3 years) were instructed to walk at a self-selected comfortable pace for 15 min in three different conditions in a randomized order: (1) overground walking, (2) TW without holding a handrail (NoRail) and (3) TW while holding a front handrail (Rail). The alpha did not differ significantly between the overground and NoRail conditions (P>0.5). However, the alpha of the Rail condition (alpha=0.92+/-0.10) differed significantly from both the overground (alpha=0.83+/-0.06; P<0.015) and NoRail conditions (alpha=0.82+/-0.08; P<0.01). In contrast, stride interval variability did not change between walking conditions (P>0.5). These findings indicate that comfortable-paced TW does not diminish the intrinsic stride dynamics of human gait.

  15. Modeling circadian and sleep-homeostatic effects on short-term interval timing

    PubMed Central

    Späti, Jakub; Aritake, Sayaka; Meyer, Andrea H.; Kitamura, Shingo; Hida, Akiko; Higuchi, Shigekazu; Moriguchi, Yoshiya; Mishima, Kazuo

    2015-01-01

    Short-term interval timing i.e., perception and action relating to durations in the seconds range, has been suggested to display time-of-day as well as wake dependent fluctuations due to circadian and sleep-homeostatic changes to the rate at which an underlying pacemaker emits pulses; pertinent human data being relatively sparse and lacking in consistency however, the phenomenon remains elusive and its mechanism poorly understood. To better characterize the putative circadian and sleep-homeostatic effects on interval timing and to assess the ability of a pacemaker-based mechanism to account for the data, we measured timing performance in eighteen young healthy male subjects across two epochs of sustained wakefulness of 38.67 h each, conducted prior to (under entrained conditions) and following (under free-running conditions) a 28 h sleep-wake schedule, using the methods of duration estimation and duration production on target intervals of 10 and 40 s. Our findings of opposing oscillatory time courses across both epochs of sustained wakefulness that combine with increasing and, respectively, decreasing, saturating exponential change for the tasks of estimation and production are consistent with the hypothesis that a pacemaker emitting pulses at a rate controlled by the circadian oscillator and increasing with time awake determines human short-term interval timing; the duration-specificity of this pattern is interpreted as reflecting challenges to maintaining stable attention to the task that progressively increase with stimulus magnitude and thereby moderate the effects of pacemaker-rate changes on overt behavior. PMID:25741253

  16. The Effects of High Intensity Interval Training vs Steady State Training on Aerobic and Anaerobic Capacity

    PubMed Central

    Foster, Carl; Farland, Courtney V.; Guidotti, Flavia; Harbin, Michelle; Roberts, Brianna; Schuette, Jeff; Tuuri, Andrew; Doberstein, Scott T.; Porcari, John P.

    2015-01-01

    High intensity interval training (HIIT) has become an increasingly popular form of exercise due to its potentially large effects on exercise capacity and small time requirement. This study compared the effects of two HIIT protocols vs steady-state training on aerobic and anaerobic capacity following 8-weeks of training. Fifty-five untrained college-aged subjects were randomly assigned to three training groups (3x weekly). Steady-state (n = 19) exercised (cycle ergometer) 20 minutes at 90% of ventilatory threshold (VT). Tabata (n = 21) completed eight intervals of 20s at 170% VO2max/10s rest. Meyer (n = 15) completed 13 sets of 30s (20 min) @ 100% PVO2 max/ 60s recovery, average PO = 90% VT. Each subject did 24 training sessions during 8 weeks. Results: There were significant (p < 0.05) increases in VO2max (+19, +18 and +18%) and PPO (+17, +24 and +14%) for each training group, as well as significant increases in peak (+8, + 9 and +5%) & mean (+4, +7 and +6%) power during Wingate testing, but no significant differences between groups. Measures of the enjoyment of the training program indicated that the Tabata protocol was significantly less enjoyable (p < 0.05) than the steady state and Meyer protocols, and that the enjoyment of all protocols declined (p < 0.05) across the duration of the study. The results suggest that although HIIT protocols are time efficient, they are not superior to conventional exercise training in sedentary young adults. Key points Steady state training equivalent to HIIT in untrained students Mild interval training presents very similar physiologic challenge compared to steady state training HIIT (particularly very high intensity variants were less enjoyable than steady state or mild interval training Enjoyment of training decreases across the course of an 8 week experimental training program PMID:26664271

  17. Effects of On-Demand Versus Fixed-Interval Schedules in the Treatment of Chronic Pain With Analgesic Compounds.

    ERIC Educational Resources Information Center

    Berntzen, Dagfinn; Gotestam, K. Gunnar

    1987-01-01

    Compared the effects of fixed-interval and on-demand administration of analgesic medications in chronic pain patients. A fixed-interval analgesic schedule was found more effective than an on-demand schedule in reducing subjective pain and elevating mood. No differences were found between the two conditions on measures of physical activity.…

  18. Representing the Hyphen in Action-Effect Associations: Automatic Acquisition and Bidirectional Retrieval of Action-Effect Intervals

    ERIC Educational Resources Information Center

    Dignath, David; Pfister, Roland; Eder, Andreas B.; Kiesel, Andrea; Kunde, Wilfried

    2014-01-01

    We examined whether a temporal interval between an action and its sensory effect is integrated in the cognitive action structure in a bidirectional fashion. In 3 experiments, participants first experienced that actions produced specific acoustic effects (high and low tones) that occurred temporally delayed after their actions. In a following test…

  19. Salutary effects of high-intensity interval training in persons with elevated cardiovascular risk.

    PubMed

    Fleg, Jerome L

    2016-01-01

    Although moderate-intensity continuous training (MICT) has been the traditional model for aerobic exercise training for over four decades, a growing body of literature has demonstrated equal if not greater improvement in aerobic capacity and similar beneficial effects on body composition, glucose metabolism, blood pressure, and quality of life from high-intensity interval training (HIIT). An advantage of HIIT over MICT is the shorter time required to perform the same amount of energy expenditure. The current brief review summarizes the effects of HIIT on peak aerobic capacity and cardiovascular risk factors in healthy adults and those with various cardiovascular diseases, including coronary artery disease, chronic heart failure, and post heart transplantation.

  20. Salutary effects of high-intensity interval training in persons with elevated cardiovascular risk

    PubMed Central

    Fleg, Jerome L.

    2016-01-01

    Although moderate-intensity continuous training (MICT) has been the traditional model for aerobic exercise training for over four decades, a growing body of literature has demonstrated equal if not greater improvement in aerobic capacity and similar beneficial effects on body composition, glucose metabolism, blood pressure, and quality of life from high-intensity interval training (HIIT). An advantage of HIIT over MICT is the shorter time required to perform the same amount of energy expenditure. The current brief review summarizes the effects of HIIT on peak aerobic capacity and cardiovascular risk factors in healthy adults and those with various cardiovascular diseases, including coronary artery disease, chronic heart failure, and post heart transplantation.

  1. Effect of high-intensity interval exercise on basal triglyceride metabolism in non-obese men.

    PubMed

    Bellou, Elena; Magkos, Faidon; Kouka, Tonia; Bouchalaki, Eirini; Sklaveniti, Dimitra; Maraki, Maria; Tsekouras, Yiannis E; Panagiotakos, Demosthenes B; Kavouras, Stavros A; Sidossis, Labros S

    2013-08-01

    A single bout of high-intensity interval aerobic exercise has been shown to produce the same or greater metabolic benefits as continuous endurance exercise with considerably less energy expenditure, but whether this applies to very low density lipoprotein (VLDL) metabolism is not known. We sought to examine the effect of a single bout of high-intensity interval aerobic exercise on basal VLDL-triglyceride (TG) kinetics 14 and 48 h after exercise cessation to determine the acute and time-dependent effects of this type of exercise on VLDL-TG metabolism. Eight healthy sedentary men (age, 23.6 ± 6.1 years; body mass index, 23.1 ± 2.2 kg·m(-2), peak oxygen consumption (V̇O2peak), 36.3 ± 5.5 mL·kg(-1)·min(-1)) participated in three stable isotopically labeled tracer infusion studies: (i) 14 h and (ii) 48 h after a single bout of high-intensity aerobic interval exercise (60% and 90% of V̇O2peak in 4 min intervals for a total of 32 min; gross energy expenditure ∼500 kcal) and (iii) after an equivalent period of rest, in random order. Fasting plasma VLDL-TG concentration was 20% lower at 14 h (P = 0.046) but not at 48 h (P = 1.000) after exercise compared with the resting trial. VLDL-TG plasma clearance rate increased by 21% at 14 h (P < 0.001) but not at 48 h (P = 0.299) after exercise compared with rest, whereas hepatic VLDL-TG secretion rate was not different from rest at any time point after exercise. We conclude that high-intensity interval exercise reduces fasting plasma VLDL-TG concentrations in non-obese men the next day by augmenting VLDL-TG clearance, just like a single bout of continuous endurance exercise. This effect is short-lived and abolished by 48 h after exercise.

  2. Twice-weighted multiple interval estimation of a marginal structural model to analyze cost-effectiveness.

    PubMed

    Goldfeld, K S

    2014-03-30

    Cost-effectiveness analysis is an important tool that can be applied to the evaluation of a health treatment or policy. When the observed costs and outcomes result from a nonrandomized treatment, making causal inference about the effects of the treatment requires special care. The challenges are compounded when the observation period is truncated for some of the study subjects. This paper presents a method of unbiased estimation of cost-effectiveness using observational study data that is not fully observed. The method-twice-weighted multiple interval estimation of a marginal structural model-was developed in order to analyze the cost-effectiveness of treatment protocols for advanced dementia residents living nursing homes when they become acutely ill. A key feature of this estimation approach is that it facilitates a sensitivity analysis that identifies the potential effects of unmeasured confounding on the conclusions concerning cost-effectiveness.

  3. Interval, blocking, and marking effects during the development of schedule-induced drinking in rats.

    PubMed

    Patterson, Angela E; Boakes, Robert A

    2012-07-01

    Schedule-induced drinking (SID) can occur when food-deprived rats are given access to water while receiving pellets on an intermittent reinforcement schedule. These conditions can increase water intake excessively. The possible role of adventitious reinforcement of postpellet drinking was assessed by testing whether response-reinforcer contiguity, the relative predictiveness of a response, and whether it is marked are important in the development of SID. Rats exposed to a short interpellet interval acquired SID most rapidly, with this acquired drinking response maintained when animals were transferred to a longer interpellet interval, thus indicating an easy-to-hard effect (Experiment 1). Further experiments demonstrated that a stimulus (a brief-flashing house light) occurring prior to pellet delivery could block the acquisition of SID (Experiment 2), while a lick-contingent tone, intended to increase the associability of this response, produced more rapid acquisition of SID (Experiment 3). Analysis of lick distributions revealed that licking became concentrated in the first half of an interpellet interval only after several sessions. Overall, the results indicated that similar factors affect the acquisition of both SID and instrumental conditioning with delayed reinforcement, as is consistent with a superstitious conditioning account of SID development.

  4. Effect of Different Rest Intervals on the Exercise Volume Completed During Squat Bouts

    PubMed Central

    Rahimi, Rahman

    2005-01-01

    The purpose of this research was to compare effect 3 different rest intervals on the squat volume completed during a workout. Twenty college-aged men volunteered to participate in this study (age 20.73 ± 2.60 years; body mass 80.73 ± 10.80 kg). All subjects performed 3 testing sessions, during which 4 sets of the squat was performed with 85% of a 1RM load. During each testing session, the squat was performed with a 1, 2, or 5-minute rest interval between sets. Volume was defined as the total number of repetitions completed over 4 sets for each rest condition. Statistical analysis was conducted separately for the squat. One-way repeated analyses of variance with Bonferroni post hocs demonstrated significant differences between each rest condition for both exercises tested (p < 0.05). The 5-minute rest condition resulted in the highest volume completed, followed in descending order by the 2- and 1-minute rest conditions. The ability to perform a higher volume of training with a given load may stimulate greater strength adaptations. Key Points There is no significant difference in the squat volume between the 1- and 2-minute rest conditions. A 5-minute rest interval between sets allow for the highest volume to be completed when training with 85% of a 1RM load. PMID:24501549

  5. The effect of tafamidis on the QTc interval in healthy subjects

    PubMed Central

    Klamerus, Karen J; Watsky, Eric; Moller, Robert; Wang, Ronnie; Riley, Steve

    2015-01-01

    Aims The transthyretin (TTR) stabilizer, tafamidis, has demonstrated efficacy and safety in the treatment of TTR familial amyloid polyneuropathy (20 mg day−1). Tafamidis use in TTR cardiomyopathy led to the study of the potential effect of tafamidis on the QTc interval in healthy subjects. Methods This randomized, three treatment, three period, six sequence crossover study with placebo, a positive control (moxifloxacin 400 mg) and tafamidis (400 mg, to achieve a supra-therapeutic Cmax of ∽20 µg ml−1) was conducted in healthy volunteers at three clinical research units. Oral dosing in each of the three treatment periods was separated by a washout period of  ≥ 14 days. Serial triplicate 12-lead electrocardiograms were performed. QTc intervals were derived using the Fridericia correction method. Safety and tolerability were assessed by physical examination, vital signs measurement, laboratory analyses and monitoring of adverse events (AEs). Results A total of 42 subjects completed the study. The upper limit of the two-sided 90% confidence intervals (CIs) for the difference in baseline-adjusted QTcF between tafamidis 400 mg and placebo was <10 ms (non-inferiority criterion) for all time points. The lower limit of the two-sided 90% CI between moxifloxacin 400 mg and placebo exceeded 5 ms at the pre-specified moxifloxacin tmax of 3 h post-dose, confirming assay sensitivity. Cmax and AUC(0,24 h) for tafamidis were 20.36 µg ml−1 and 305.4 µg ml−1 h, respectively. There were no serious/severe AEs or treatment discontinuations due to AEs. Conclusions This thorough QTc study suggests that a supra-therapeutic single 400 mg oral dose of tafamidis does not prolong the QTc interval and is well-tolerated in healthy volunteers. PMID:25546001

  6. The effects of different electrolyte composition in dialysate on QTc interval; a controlled trial

    PubMed Central

    Sabzghabaei, Foroogh; Heydariezade, Seyed Alireza; Joodat, Rashin S

    2016-01-01

    Introduction: Hemodialysis (HD) has impact on the cardiovascular system by inducing changes in the characteristics of body fluids such as PH, temperature and electrolyte concentrations. In the previous studies, prolongation of the QT interval and increase of QT dispersion have been reported during HD sessions. These changes were more significant while using solutions with less potassium and higher bicarbonate during dialysis. Objectives: The aim of our study was to investigate the effects of different potassium and bicarbonate concentrations on electrocardiography (ECG) parameters and the electrochemical balance of cell membranes. Patients and Methods: This is a double blind controlled clinical trial with crossover design. This interventional study has been conducted on 36 patients over 18 years who undergoing HD 3 times a week for at least 6 months. Twelve-lead ECG has been obtained before starting and one hour after end of each HD session. The QTc was measured and changes recorded by a cardiologist. Correlations were evaluated by univariate regression analysis. Results: 54.38 years (16 to 77 years), 66.7% were male. No significant increase in QT interval has been seen while dialyzing with 2 meq/l potassium and 24 meq/l bicarbonate, 2 meq/l potassium and 28 meq/l bicarbonate and 3 meq/l potassium and 24 meq/l bicarbonate beside high calcium (2.5 meq/l) dialysate was conducted. Age, gender, serum calcium and serum bicarbonate level before HD session did not influence the mean QT intervals before and after dialysis. Conclusion: Concentration of potassium beside moderate dose of bicarbonate in dialysis bath had not any significant influence on QT intervals after dialysis. PMID:27689113

  7. Effects of high-intensity interval training on cardiometabolic risk factors in overweight/obese women.

    PubMed

    Smith-Ryan, Abbie E; Trexler, Eric T; Wingfield, Hailee L; Blue, Malia N M

    2016-11-01

    The purpose of this study was to evaluate two practical interval training protocols on cardiorespiratory fitness, lipids and body composition in overweight/obese women. Thirty women (mean ± SD; weight: 88.1 ± 15.9 kg; BMI: 32.0 ± 6.0 kg · m(2)) were randomly assigned to ten 1-min high-intensity intervals (90%VO2 peak, 1 min recovery) or five 2-min high-intensity intervals (80-100% VO2 peak, 1 min recovery) or control. Peak oxygen uptake (VO2 peak), peak power output (PPO), body composition and fasting blood lipids were evaluated before and after 3 weeks of training, completed 3 days per week. Results from ANCOVA analyses demonstrated no significant training group differences for any primary variables (P > 0.05). When training groups were collapsed, 1MIN and 2MIN resulted in a significant increase in PPO (∆18.9 ± 8.5 watts; P = 0.014) and time to exhaustion (∆55.1 ± 16.4 s; P = 0.001); non-significant increase in VO2 peak (∆2.36 ± 1.34 ml · kg(-)(1) · min(-)(1); P = 0.185); and a significant decrease in fat mass (FM) (-∆1.96 ± 0.99 kg; P = 0.011). Short-term interval exercise training may be effective for decreasing FM and improving exercise tolerance in overweight and obese women.

  8. Effects of high-intensity interval training on cardiometabolic risk factors in overweight/obese women

    PubMed Central

    Smith-Ryan, Abbie E.; Trexler, Eric T.; Wingfield, Hailee; Blue, Malia N.M.

    2016-01-01

    The purpose of this study was to evaluate two practical interval training protocols on cardiorespiratory fitness, lipids, and body composition in overweight/obese women. Thirty women (mean ± SD; Weight: 88.1 ± 15.9 kg; BMI: 32.0 ± 6.0 kg·m2) were randomly assigned to ten 1-minute high-intensity intervals (90%VO2peak, 1min recovery), or five 2-minute high-intensity intervals (80-100% VO2peak, 1 min recovery), or control. Peak oxygen uptake (VO2peak), peak power output, body composition, and fasting blood lipids were evaluated before and after 3 weeks of training, completed 3 days per week. Results from ANCOVA analyses demonstrated no significant training group differences for any primary variables (p>0.05). When training groups were collapsed, 1MIN and 2MIN resulted in a significant increase in peak power output (∆18.9 ± 8.5 watts; p=0.014) and time to exhaustion (∆55.1 ± 16.4 sec; p=0.001); non-significant increase in VO2peak (∆2.36 ± 1.34 ml·kg−1·min−1; p=0.185); and a significant decrease in fat mass (∆−1.96 ± 0.99kg; p=0.011). Short-term interval exercise training may be effective for decreasing fat mass and improving exercise tolerance in overweight and obese women. PMID:26934687

  9. Effects of high-intensity interval training on cardiometabolic risk factors in overweight/obese women.

    PubMed

    Smith-Ryan, Abbie E; Trexler, Eric T; Wingfield, Hailee L; Blue, Malia N M

    2016-11-01

    The purpose of this study was to evaluate two practical interval training protocols on cardiorespiratory fitness, lipids and body composition in overweight/obese women. Thirty women (mean ± SD; weight: 88.1 ± 15.9 kg; BMI: 32.0 ± 6.0 kg · m(2)) were randomly assigned to ten 1-min high-intensity intervals (90%VO2 peak, 1 min recovery) or five 2-min high-intensity intervals (80-100% VO2 peak, 1 min recovery) or control. Peak oxygen uptake (VO2 peak), peak power output (PPO), body composition and fasting blood lipids were evaluated before and after 3 weeks of training, completed 3 days per week. Results from ANCOVA analyses demonstrated no significant training group differences for any primary variables (P > 0.05). When training groups were collapsed, 1MIN and 2MIN resulted in a significant increase in PPO (∆18.9 ± 8.5 watts; P = 0.014) and time to exhaustion (∆55.1 ± 16.4 s; P = 0.001); non-significant increase in VO2 peak (∆2.36 ± 1.34 ml · kg(-)(1) · min(-)(1); P = 0.185); and a significant decrease in fat mass (FM) (-∆1.96 ± 0.99 kg; P = 0.011). Short-term interval exercise training may be effective for decreasing FM and improving exercise tolerance in overweight and obese women. PMID:26934687

  10. Effect of sprint interval exercise on postexercise metabolism and blood pressure in adolescents.

    PubMed

    Burns, Stephen F; Oo, Hnin Hnin; Tran, Anh Thanh Thuy

    2012-02-01

    The current study examined the effect of sprint interval exercise on postexercise oxygen consumption, respiratory-exchange ratio (RER), substrate oxidation, and blood pressure in adolescents. Participants were 10 normal-weight healthy youth (7 female), age 15-18 years. After overnight fasts, each participant undertook 2 trials in a random balanced order: (a) two 30-s bouts of sprint interval exercise on a cycle ergometer and (b) rested in the laboratory for an equivalent period. Time-matched measurements of oxygen consumption, RER, and blood pressure were made 90 min into recovery, and substrate oxidation were calculated over the time period. Total postexercise oxygen uptake was significantly higher in the exercise than control trial over the 90 min (mean [SD]: control 20.0 [6.0] L, exercise 24.8 [9.8] L; p=.030). After exercise, RER was elevated above control but then fell rapidly and was lower than control 30-60 min postexercise, and fat oxidation was significantly higher in the exercise than control trial 45-60 min postexercise. However, total fat oxidation did not differ between trials (control 4.5 [2.5] g, exercise 5.4 [2.7] g; p=.247). Post hoc tests revealed that systolic blood pressure was significantly lower than in control at 90 min postexercise (control 104 [10] mm Hg, exercise 99 [10] mm Hg; p<.05). These data indicate that acute sprint interval exercise leads to short-term increases in oxygen uptake and reduced blood pressure in youth. The authors suggest that health outcomes in response to sprint interval training be examined in children.

  11. The effect of signaled reinforcement on rats' fixed-interval responding.

    PubMed Central

    Reed, Phil

    2003-01-01

    Four experiments examined the effect on rats' response rate of presenting a brief (500 ms) stimulus simultaneously with the delivery of food on fixed-interval (FI) schedules. In Experiment 1, reinforcement signals that were spatially diffuse (both tones and lights) elevated rates of responding, but responding was attenuated by localized visual stimuli. The remaining experiments examined the signal-induced potentiation of responding. In Experiment 2, a tone reinforcement signal potentiated response rates on an FI schedule, but attenuated response rates on a variable-interval (VI) schedule. This difference was obtained even though the overall rate of responding was equated on the two schedules before the introduction of the signal. Signal-induced potentiation of responding occurred over a range of FI values employed in Experiment 3. In Experiment 4, presenting a reinforcement signal when high local rates of response had occurred immediately before reinforcement resulted in potentiated rates of responding on an FI schedule. The opposite effect on response rate occurred when the reinforcement signal followed only low local rates of response. These results indicate that a variety of factors influence the effects of a reinforcement signal. They imply, however, that the local rate of response at the time of reinforcement is a key factor in establishing the nature of the signaling effect. PMID:12908763

  12. Oral Contraceptive Use and the ECG: Evidence of an Adverse QT Effect on Corrected QT Interval

    PubMed Central

    Sedlak, Tara; Shufelt, Chrisandra; Iribarren, Carlos; Lyon, Liisa L; Merz, C. Noel Bairey

    2013-01-01

    Background A prolonged corrected QT (QTc) interval is a marker for an increased risk of sudden cardiac death. We evaluated the relationship between oral contraceptive (OC) use, type of OC, and QTc interval. Methods We identified 410,782 ECGs performed at Northern California Kaiser Permanente on female patients between 15–53 years from January, 1995 to June, 2008. QT was corrected for heart rate using log-linear regression. OC generation (first, second and third) was classified by increasing progestin androgenic potency, while the fourth generation was classified as anti-androgenic. Results Among 410,782 women, 8.4% were on OC. In multivariate analysis after correction for comorbidities, there was an independent shortening effect of OCs overall (slope = −0.5ms; SE = 0.12, p<0.0002). Users of first and second generation progestins had a significantly shorter QTc than non-users (p<0.0001), while users of fourth generation had a significantly longer QTc than non-users (slope = 3.6ms, SE = 0.35, p<0.0001). Conclusion Overall, OC use has a shortening effect on the QTc. Shorter QTc is seen with first and second generation OC while fourth generation OC use has a lengthening effect on the QTc. Careful examination of adverse event rates in fourth generation OC users is needed. PMID:23879279

  13. Quantification of the acute effect of a low dose of red wine by nonlinear measures of RR and QT interval series in healthy subjects.

    PubMed

    Platiša, Mirjana M; Gal, Vera; Nestorović, Zorica; Gojković-Bukarica, Ljiljana

    2014-10-01

    The measures of nonlinear properties of RR interval and QT interval time series are sensitive to physiologically- or pathologically-induced complexity/regularity changes, but were not used to estimate the effect of alcohol intake. We wanted to examine the potential of these measures to quantify the acute effect of a low dose of red wine in healthy subjects. In separate experiments, fourteen young volunteers drank 200ml of red wine and a control drink with equal concentration of ethanol. ECG in supine position was recorded 20min before and 60min after drink intake. RR interval and QT interval series were extracted from ECG and we calculated variability, scaling exponents (α1 and α2) and sample entropy (SampEn) for both series. Systolic and diastolic blood pressures (BP) were measured every 10min. The immediate effect of both the drinks was equal: HR, BP and QT variability exhibited a sudden increase and then a decrease. However, the prolonged effect of wine and the control drink was different. Wine decreased both BP (p<0.05) and reduced complexity of RR and QT series (increased scaling exponents and decreased SampEn). The control drink prolonged QT and RR intervals (p<0.05). These results point out that the nonlinear properties of RR and QT interval series could be used to differentiate the effect of wine and ethanol. Changes in RR and QT interval series induced by a low dose of red wine are more detectable by methods that quantify the structure of the series than by methods that quantify their variability.

  14. Lack of an effect of standard and supratherapeutic doses of linezolid on QTc interval prolongation.

    PubMed

    Damle, Bharat; Labadie, Robert R; Cuozzo, Cheryl; Alvey, Christine; Choo, Heng Wee; Riley, Steve; Kirby, Deborah

    2011-09-01

    A double-blind, placebo-controlled, four-way crossover study was conducted in 40 subjects to assess the effect of linezolid on corrected QT (QTc) interval prolongation. Time-matched, placebo-corrected QT intervals were determined predose and at 0.5, 1 (end of infusion), 2, 4, 8, 12, and 24 h after intravenous dosing of linezolid 600 and 1,200 mg. Oral moxifloxacin at 400 mg was used as an active control. The pharmacokinetic profile of linezolid was also evaluated. At each time point, the upper bound of the 90% confidence interval (CI) for placebo-corrected QTcF values (i.e., QTc values adjusted for ventricular rate using the correction methods of Fridericia) for linezolid 600 and 1,200-mg doses were <10 ms, which indicates an absence of clinically significant QTc prolongation. At 2 and 4 h after the moxifloxacin dose, corresponding to the population T(max), the lower bound of the two-sided 90% CI for QTcF when comparing moxifloxacin to placebo was >5 ms, indicating that the study was adequately sensitive to assess QTc prolongation. The pharmacokinetic profile of linezolid at 600 mg was consistent with previous observations. Systemic exposure to linezolid increased in a slightly more than dose-proportional manner at supratherapeutic doses, but the degree of nonlinearity was small. At a supratherapeutic single dose of 1,200 mg of linezolid, no treatment-related increase in adverse events was seen compared to 600 mg of linezolid, and no clinically meaningful effects on vital signs and safety laboratory evaluations were noted. PMID:21709083

  15. The effects of high intensity interval training in normobaric hypoxia on aerobic capacity in basketball players.

    PubMed

    Czuba, Miłosz; Zając, Adam; Maszczyk, Adam; Roczniok, Robert; Poprzęcki, Stanisław; Garbaciak, Wiesław; Zając, Tomasz

    2013-12-18

    . This data suggest that an intermittent hypoxic training protocol with high intensity intervals (4 to 5 × 4 min bouts at 90% of vVO2max-hyp) is an effective training means for improving aerobic capacity at sea level in basketball players.

  16. One-sided tolerance interval in a two-way balanced nested model with mixed effects

    NASA Astrophysics Data System (ADS)

    Silva, A.; Carvalho, F.; Mexia, J.; Fonseca, M.

    2013-10-01

    In this paper we approach the construction of the both upper and lower tolerance limit in a two-way nested model with mixed effects in balanced data. In order to do so we proceed as Fonseca et al [3] did in order to derive the upper tolerance limit in a two-way nested model with mixed effects in unbalanced data, by using the generalized confidence interval idea earlier used by Krishnamoorthy and Mathew [4] to perform the construction of the upper tolerance limit in a one-way nested model with mixed or random effects model in balanced and unbalanced data. The underlying idea goes through the construction of an approximation for the quantile of the general pivotal quantity for a convenient parametric function.

  17. BootES: an R package for bootstrap confidence intervals on effect sizes.

    PubMed

    Kirby, Kris N; Gerlanc, Daniel

    2013-12-01

    Bootstrap Effect Sizes (bootES; Gerlanc & Kirby, 2012) is a free, open-source software package for R (R Development Core Team, 2012), which is a language and environment for statistical computing. BootES computes both unstandardized and standardized effect sizes (such as Cohen's d, Hedges's g, and Pearson's r) and makes easily available for the first time the computation of their bootstrap confidence intervals (CIs). In this article, we illustrate how to use bootES to find effect sizes for contrasts in between-subjects, within-subjects, and mixed factorial designs and to find bootstrap CIs for correlations and differences between correlations. An appendix gives a brief introduction to R that will allow readers to use bootES without having prior knowledge of R.

  18. Salient stimuli in advertising: the effect of contrast interval length and type on recall.

    PubMed

    Olsen, G Douglas

    2002-09-01

    Salient auditory stimuli (e.g., music or sound effects) are commonly used in advertising to elicit attention. However, issues related to the effectiveness of such stimuli are not well understood. This research examines the ability of a salient auditory stimulus, in the form of a contrast interval (CI), to enhance recall of message-related information. Researchers have argued that the effectiveness of the CI is a function of the temporal duration between the onset and offset of the change in the background stimulus and the nature of this stimulus. Three experiments investigate these propositions and indicate that recall is enhanced, providing the CI is 3 s or less. Information highlighted with silence is recalled better than information highlighted with music.

  19. Effects of wait-time and intertrial interval durations on learning by children with multiple handicaps.

    PubMed Central

    Valcante, G; Roberson, W; Reid, W R; Wolking, W D

    1989-01-01

    We investigated the influence of teacher wait-time and intertrial interval durations on the performance of 4 multiply handicapped students during instruction in 10 skills. Four experimental conditions were evaluated: long wait-time and long intertrial interval, long wait-time and short intertrial interval, short wait-time and long intertrial interval, and short wait-time and short intertrial interval. Instructors attempted to keep short intervals as close as possible to 1 s and long intervals as close as possible to 10 s for both variables. Results showed that student performance was superior under the long wait-time conditions irrespective of the length of the intertrial interval. PMID:2523372

  20. Improvement spatial resolution of frequency modulated continuous wave laser ranging system by splicing equal optical frequency interval sampled signal

    NASA Astrophysics Data System (ADS)

    Shi, Guang; Zhang, Fumin; Qu, Xinghua

    2015-02-01

    A dual interferometry FMCW laser ranging system is presented. The auxiliary interferometer for generating the clock pulses at equally spaced optical frequencies is incorporated into the main interferometer to simplify the system configuration and to compensate the tuning linearity of the laser source. The need of widely tunable laser limits the practical application of the FMCW laser ranging for precision industrial measurement. Splicing sampled signal method is proposed to break though the tuning range of the laser source limitation against the special resolution. In the experiments, 50 μm range resolution at 8.7 m is demonstrated, and this resolution is maintained over the entire measuring range. The measuring range depending on the power and coherence length of the source can reach more than 20 m. The system structure is simple, and the requirement on the tuning range of laser source is reduced in this system.

  1. The effect of filled and empty intervals on clock and memory processes in pigeons.

    PubMed

    Price, Elizabeth; Santi, Angelo

    2014-06-01

    According to the mixed memory model (Penney, Gibbon, & Meck, Journal of Experimental Psychology: Human Perception and Performance, 26, 1770-1787, 2000), different clock rates for stimuli with different nontemporal properties must be stored within a single reference memory distribution in order to detect a difference between the clock rates of the different signals. In Experiment 1, pigeons were trained in a between-subjects design to discriminate empty intervals (bound by two 1-s visual markers) and filled intervals (a continuous visual signal). The intervals were signaled by different visual stimuli, and they required responses to different sets of comparison stimuli. Empty intervals were judged as being longer than filled intervals. The difference between the point of subjective equality (PSE) for the empty intervals and the PSE for the filled intervals increased proportionally as the magnitudes of the anchor duration pairs were increased from 2 and 8 s to 4 and 16 s. In Experiment 2, the pigeons were trained to discriminate intervals signaled by the absence of houselight illumination (Group Empty) or the presence of houselight illumination (Group Filled). The psychophysical timing functions for these intervals were identical to each other. The results of Experiment 1 indicate that memory mixing is not necessary for detecting a timing difference between empty and filled intervals in pigeons. The results of Experiment 2 suggest that the nature of the stimuli that signal the empty and filled intervals impacts how pigeons judge the durations of empty and filled intervals.

  2. The Effects of Interval Duration on Temporal Tracking and Alternation Learning

    ERIC Educational Resources Information Center

    Ludvig, Elliot A.; Staddon, John E. R.

    2005-01-01

    On cyclic-interval reinforcement schedules, animals typically show a postreinforcement pause that is a function of the immediately preceding time interval ("temporal tracking"). Animals, however, do not track single-alternation schedules--when two different intervals are presented in strict alternation on successive trials. In this experiment,…

  3. Design and Operation of a Borehole Straddle Packer for Ground-Water Sampling and Hydraulic Testing of Discrete Intervals at U.S. Air Force Plant 6, Marietta, Georgia

    USGS Publications Warehouse

    Holloway, Owen G.; Waddell, Jonathan P.

    2008-01-01

    A borehole straddle packer was developed and tested by the U.S. Geological Survey to characterize the vertical distribution of contaminants, head, and hydraulic properties in open-borehole wells as part of an ongoing investigation of ground-water contamination at U.S. Air Force Plant 6 (AFP6) in Marietta, Georgia. To better understand contaminant fate and transport in a crystalline bedrock setting and to support remedial activities at AFP6, numerous wells have been constructed that include long open-hole intervals in the crystalline bedrock. These wells can include several discontinuities that produce water, which may contain contaminants. Because of the complexity of ground-water flow and contaminant movement in the crystalline bedrock, it is important to characterize the hydraulic and water-quality characteristics of discrete intervals in these wells. The straddle packer facilitates ground-water sampling and hydraulic testing of discrete intervals, and delivery of fluids including tracer suites and remedial agents into these discontinuities. The straddle packer consists of two inflatable packers, a dual-pump system, a pressure-sensing system, and an aqueous injection system. Tests were conducted to assess the accuracy of the pressure-sensing systems, and water samples were collected for analysis of volatile organic compound (VOCs) concentrations. Pressure-transducer readings matched computed water-column height, with a coefficient of determination of greater than 0.99. The straddle packer incorporates both an air-driven piston pump and a variable-frequency, electronic, submersible pump. Only slight differences were observed between VOC concentrations in samples collected using the two different types of sampling pumps during two sampling events in July and August 2005. A test conducted to assess the effect of stagnation on VOC concentrations in water trapped in the system's pump-tubing reel showed that concentrations were not affected. A comparison was conducted

  4. Effects of a reduced time-out interval on compliance with the time-out instruction.

    PubMed

    Donaldson, Jeanne M; Vollmer, Timothy R; Yakich, Theresa M; Van Camp, Carole

    2013-01-01

    Time-out is a negative punishment procedure that parents and teachers commonly use to reduce problem behavior; however, specific time-out parameters have not been evaluated adequately. One parameter that has received relatively little attention in the literature is the mode of administration (verbal or physical) of time-out. In this study, we evaluated a procedure designed to reduce problem behavior and increase compliance with the verbal instruction to go to time-out. Specifically, we reduced the time-out interval contingent on compliance with the time-out instruction. Six preschool-aged boys participated in the study. Time-out effectively reduced the problem behavior of all 6 participants, and the procedure to increase compliance with the time-out instruction was effective for 4 of 6 participants. PMID:24114153

  5. Salutary effects of high-intensity interval training in persons with elevated cardiovascular risk

    PubMed Central

    Fleg, Jerome L.

    2016-01-01

    Although moderate-intensity continuous training (MICT) has been the traditional model for aerobic exercise training for over four decades, a growing body of literature has demonstrated equal if not greater improvement in aerobic capacity and similar beneficial effects on body composition, glucose metabolism, blood pressure, and quality of life from high-intensity interval training (HIIT). An advantage of HIIT over MICT is the shorter time required to perform the same amount of energy expenditure. The current brief review summarizes the effects of HIIT on peak aerobic capacity and cardiovascular risk factors in healthy adults and those with various cardiovascular diseases, including coronary artery disease, chronic heart failure, and post heart transplantation. PMID:27635241

  6. Acute marijuana effects on response-reinforcer relations under multiple variable-interval schedules.

    PubMed

    Lane, S D; Cherek, D R; Pietras, C J; Tcheremissine, O V

    2004-07-01

    Acute marijuana administration may alter response-reinforcer relationships via a change in reinforcer efficacy, but may also impair coordination and motor function. One approach to evaluating drug effects on both motor function and reinforcer efficacy involves fitting the matching law equation to data obtained under multiple variable interval (VI) schedules. The present report describes an experiment that examined the effects of acute marijuana on response properties using this approach. Six human subjects responded under a multiple VI schedule for monetary reinforcers after smoking placebo and two active doses of marijuana. The low marijuana dose produced unsystematic changes in responding. As measured by the matching law equation parameters (k and rB), at the high dose five subjects showed a decrease-motor-related properties of response rate and four subjects' responding indicated a decrease in reinforcer efficacy. These data raise the possibility that, at high doses, marijuana administration alters both motor function and reinforcer efficacy.

  7. Effects of a reduced time-out interval on compliance with the time-out instruction.

    PubMed

    Donaldson, Jeanne M; Vollmer, Timothy R; Yakich, Theresa M; Van Camp, Carole

    2013-01-01

    Time-out is a negative punishment procedure that parents and teachers commonly use to reduce problem behavior; however, specific time-out parameters have not been evaluated adequately. One parameter that has received relatively little attention in the literature is the mode of administration (verbal or physical) of time-out. In this study, we evaluated a procedure designed to reduce problem behavior and increase compliance with the verbal instruction to go to time-out. Specifically, we reduced the time-out interval contingent on compliance with the time-out instruction. Six preschool-aged boys participated in the study. Time-out effectively reduced the problem behavior of all 6 participants, and the procedure to increase compliance with the time-out instruction was effective for 4 of 6 participants.

  8. Salutary effects of high-intensity interval training in persons with elevated cardiovascular risk.

    PubMed

    Fleg, Jerome L

    2016-01-01

    Although moderate-intensity continuous training (MICT) has been the traditional model for aerobic exercise training for over four decades, a growing body of literature has demonstrated equal if not greater improvement in aerobic capacity and similar beneficial effects on body composition, glucose metabolism, blood pressure, and quality of life from high-intensity interval training (HIIT). An advantage of HIIT over MICT is the shorter time required to perform the same amount of energy expenditure. The current brief review summarizes the effects of HIIT on peak aerobic capacity and cardiovascular risk factors in healthy adults and those with various cardiovascular diseases, including coronary artery disease, chronic heart failure, and post heart transplantation. PMID:27635241

  9. Effect of sample inhomogeneity in KAr dating

    USGS Publications Warehouse

    Engels, J.C.; Ingamells, C.O.

    1970-01-01

    Error in K-Ar ages is often due more to deficiencies in the splitting process, whereby portions of the sample are taken for potassium and for argon determination, than to imprecision in the analytical methods. The effect of the grain size of a sample and of the composition of a contaminating mineral can be evaluated, and this provides a useful guide in attempts to minimize error. Rocks and minerals should be prepared for age determination with the effects of contaminants and grain size in mind. The magnitude of such effects can be much larger than intuitive estimates might indicate. ?? 1970.

  10. Effect of Variations in IRU Integration Time Interval On Accuracy of Aqua Attitude Estimation

    NASA Technical Reports Server (NTRS)

    Natanson, G. A.; Tracewell, Dave

    2003-01-01

    During Aqua launch support, attitude analysts noticed several anomalies in Onboard Computer (OBC) rates and in rates computed by the ground Attitude Determination System (ADS). These included: 1) periodic jumps in the OBC pitch rate every 2 minutes; 2) spikes in ADS pitch rate every 4 minutes; 3) close agreement between pitch rates computed by ADS and those derived from telemetered OBC quaternions (in contrast to the step-wise pattern observed for telemetered OBC rates); 4) spikes of +/- 10 milliseconds in telemetered IRU integration time every 4 minutes (despite the fact that telemetered time tags of any two sequential IRU measurements were always 1 second apart from each other). An analysis presented in the paper explains this anomalous behavior by a small average offset of about 0.5 +/- 0.05 microsec in the time interval between two sequential accumulated angle measurements. It is shown that errors in the estimated pitch angle due to neglecting the aforementioned variations in the integration time interval by the OBC is within +/- 2 arcseconds. Ground attitude solutions are found to be accurate enough to see the effect of the variations on the accuracy of the estimated pitch angle.

  11. Hemodynamic effects of high intensity interval training in COPD patients exhibiting exercise-induced dynamic hyperinflation.

    PubMed

    Nasis, I; Kortianou, E; Vasilopoulou, Μ; Spetsioti, S; Louvaris, Z; Kaltsakas, G; Davos, C H; Zakynthinos, S; Koulouris, N G; Vogiatzis, I

    2015-10-01

    Dynamic hyperinflation (DH) has a significant adverse effect on cardiovascular function during exercise in COPD patients. COPD patients with (n = 25) and without (n = 11) exercise-induced DH undertook an incremental (IET) and a constant-load exercise test (CLET) sustained at 75% peak work (WRpeak) prior to and following an interval cycling exercise training regime (set at 100% WRpeak with 30-s work/30-s rest intervals) lasting for 12 weeks. Cardiac output (Q) was assessed by cardio-bio-impedance (PhysioFlow, enduro, PF-O7) to determine Q mean response time (QMRT) at onset (QMRT(ON)) and offset (QMRT(OFF)) of CLET. Post-rehabilitation only those patients exhibiting exercise-induced DH demonstrated significant reductions in QMRT(ON) (from 82.2 ± 4.3 to 61.7 ± 4.2 s) and QMRT(OFF) (from 80.5 ± 3.8 to 57.2 ± 4.9 s ). These post-rehabilitation adaptations were associated with improvements in inspiratory capacity, thereby suggesting that mitigation of the degree of exercise-induced DH improves central hemodynamic responses in COPD patients.

  12. Simulation of sampling effects in FPAs

    NASA Astrophysics Data System (ADS)

    Cook, Thomas H.; Hall, Charles S.; Smith, Frederick G.; Rogne, Timothy J.

    1991-09-01

    The use of multiplexers and large focal plane arrays in advanced thermal imaging systems has drawn renewed attention to sampling and aliasing issues in imaging applications. As evidenced by discussions in a recent workshop, there is no clear consensus among experts whether aliasing in sensor designs can be readily tolerated, or must be avoided at all cost. Further, there is no straightforward, analytical method that can answer the question, particularly when considering image interpreters as different as humans and autonomous target recognizers (ATR). However, the means exist for investigating sampling and aliasing issues through computer simulation. The U.S. Army Tank-Automotive Command (TACOM) Thermal Image Model (TTIM) provides realistic sensor imagery that can be evaluated by both human observers and TRs. This paper briefly describes the history and current status of TTIM, explains the simulation of FPA sampling effects, presents validation results of the FPA sensor model, and demonstrates the utility of TTIM for investigating sampling effects in imagery.

  13. Effect of jumping interval training on neuromuscular and physiological parameters: a randomized controlled study.

    PubMed

    Ache-Dias, Jonathan; Dellagrana, Rodolfo A; Teixeira, Anderson S; Dal Pupo, Juliano; Moro, Antônio R P

    2016-01-01

    This study analyzed the effect of 4 weeks of jumping interval training (JIT), included in endurance training, on neuromuscular and physiological parameters. Eighteen recreational runners, randomized in control and experimental groups, performed 40 min of running at 70% of velocity at peak oxygen uptake, for 3 times per week. Additionally, the experimental group performed the JIT twice per week, which consisted of 4 to 6 bouts of continuous vertical jumps (30 s) with 5-min intervals. Three days before and after the training period, the countermovement (CMJ) and continuous jump (CJ30), isokinetic and isometric evaluation of knee extensors/flexors, progressive maximal exercise, and submaximal constant-load exercise were performed. The JIT provoked improvement in neuromuscular performance, indicated by (i) increased jump height (4.7%; effect size (ES) = 0.99) and power output (≈ 3.7%; ES ≈ 0.82) of CMJ and rate of torque development of knee extensors in isometric contraction (29.5%; ES = 1.02); (ii) anaerobic power and capacity, represented by the mean of jump height (7.4%; ES = 0.8), and peak power output (PPO) (5.6%; ES = 0.73) of the first jumps of CJ30 and the mean of jump height (10.2%, ES = 1.04) and PPO (9.5%, ES = 1.1), considering all jumps of CJ30; and (iii) aerobic power and capacity, represented by peak oxygen uptake (9.1%, ES = 1.28), velocity at peak oxygen uptake (2.7%, ES = 1.11), and velocity corresponding to the onset of blood lactate accumulation (9.7%, ES = 1.23). These results suggest that the JIT included in traditional endurance training induces moderate to large effects on neuromuscular and physiological parameters.

  14. Sample design effects in landscape genetics

    USGS Publications Warehouse

    Oyler-McCance, Sara J.; Fedy, Bradley C.; Landguth, Erin L.

    2012-01-01

    An important research gap in landscape genetics is the impact of different field sampling designs on the ability to detect the effects of landscape pattern on gene flow. We evaluated how five different sampling regimes (random, linear, systematic, cluster, and single study site) affected the probability of correctly identifying the generating landscape process of population structure. Sampling regimes were chosen to represent a suite of designs common in field studies. We used genetic data generated from a spatially-explicit, individual-based program and simulated gene flow in a continuous population across a landscape with gradual spatial changes in resistance to movement. Additionally, we evaluated the sampling regimes using realistic and obtainable number of loci (10 and 20), number of alleles per locus (5 and 10), number of individuals sampled (10-300), and generational time after the landscape was introduced (20 and 400). For a simulated continuously distributed species, we found that random, linear, and systematic sampling regimes performed well with high sample sizes (>200), levels of polymorphism (10 alleles per locus), and number of molecular markers (20). The cluster and single study site sampling regimes were not able to correctly identify the generating process under any conditions and thus, are not advisable strategies for scenarios similar to our simulations. Our research emphasizes the importance of sampling data at ecologically appropriate spatial and temporal scales and suggests careful consideration for sampling near landscape components that are likely to most influence the genetic structure of the species. In addition, simulating sampling designs a priori could help guide filed data collection efforts.

  15. Scale and Sampling Effects on Floristic Quality

    PubMed Central

    2016-01-01

    Floristic Quality Assessment (FQA) is increasingly influential for making land management decisions, for directing conservation policy, and for research. But, the basic ecological properties and limitations of its metrics are ill defined and not well understood–especially those related to sample methods and scale. Nested plot data from a remnant tallgrass prairie sampled annually over a 12-year period, were used to investigate FQA properties associated with species detection rates, species misidentification rates, sample year, and sample grain/area. Plot size had no apparent effect on Mean C (an area’s average Floristic Quality level), nor did species detection levels above 65% detection. Simulated species misidentifications only affected Mean C values at greater than 10% in large plots, when the replaced species were randomly drawn from the broader county-wide species pool. Finally, FQA values were stable over the 12-year study, meaning that there was no evidence that the metrics exhibit year effects. The FQA metric Mean C is demonstrated to be robust to varied sample methodologies related to sample intensity (plot size, species detection rate), as well as sample year. These results will make FQA measures even more appealing for informing land-use decisions, policy, and research for two reasons: 1) The sampling effort needed to generate accurate and consistent site assessments with FQA measures is shown to be far lower than what has previously been assumed, and 2) the stable properties and consistent performance of metrics with respect to sample methods will allow for a remarkable level of comparability of FQA values from different sites and datasets compared to other commonly used ecological metrics. PMID:27489959

  16. Scale and Sampling Effects on Floristic Quality.

    PubMed

    Spyreas, Greg

    2016-01-01

    Floristic Quality Assessment (FQA) is increasingly influential for making land management decisions, for directing conservation policy, and for research. But, the basic ecological properties and limitations of its metrics are ill defined and not well understood-especially those related to sample methods and scale. Nested plot data from a remnant tallgrass prairie sampled annually over a 12-year period, were used to investigate FQA properties associated with species detection rates, species misidentification rates, sample year, and sample grain/area. Plot size had no apparent effect on Mean C (an area's average Floristic Quality level), nor did species detection levels above 65% detection. Simulated species misidentifications only affected Mean C values at greater than 10% in large plots, when the replaced species were randomly drawn from the broader county-wide species pool. Finally, FQA values were stable over the 12-year study, meaning that there was no evidence that the metrics exhibit year effects. The FQA metric Mean C is demonstrated to be robust to varied sample methodologies related to sample intensity (plot size, species detection rate), as well as sample year. These results will make FQA measures even more appealing for informing land-use decisions, policy, and research for two reasons: 1) The sampling effort needed to generate accurate and consistent site assessments with FQA measures is shown to be far lower than what has previously been assumed, and 2) the stable properties and consistent performance of metrics with respect to sample methods will allow for a remarkable level of comparability of FQA values from different sites and datasets compared to other commonly used ecological metrics. PMID:27489959

  17. The physiological response of siberian husky dogs to exercise: effect of interval training.

    PubMed

    Ready, A E; Morgan, G

    1984-02-01

    Five Siberian Husky Dogs participated in an initial study to determine their physiological response to three types of exercise. Blood samples were taken prior to, and three minutes following, a 7.5 km free run and 6 km team sled run for the determination of hemoglobin, hematocrit, red and white blood cell counts, mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, lactate dehydrogenase, creatine phosphokinase and serum glutamic pyruvic transaminase. Samples were also taken following a 90s sprint run. Heart rate was taken immediately after each run by palpation of the femoral pulse. Average heart rates following the 90s, 7.5 km and 6 km runs were 190 bpm, 211 bpm and 166 bpm, respectively. Mean lactate concentrations following the 90s, 7.5 km and 6 km runs were 1.74 mMol . 1(-1), 0.70 mMol . 1(-1), and 3.06 mMol . 1(-1), respectively. Elevation of lactate dehydrogenase and creatine phosphokinase was greatest following the 6 km sled run. Three of the above dogs were then studied before and after a 12 week interval training program, while three other dogs served as controls. The animals completed a three stage, submaximal treadmill test prior to and following the program. Pre and post blood samples were taken, and rectal temperature and heart rate were recorded continuously throughout the test. An analysis of variance was used to examine the significance of differences between and within groups. Although the response of heart rate, lactate, temperature and serum enzymes to submaximal exercise did not change with training significant differences between groups suggested that a more prolonged program may have resulted in such adaptations.

  18. Modulation of photodynamic activity with Photofrin: effect of dose, time interval, fluence, and delivery system

    NASA Astrophysics Data System (ADS)

    Garbo, Greta M.; Ballard, Jonathan R.; Harrison, Linda T.; Kik, Peter K.; Wieman, T. J.; Fingar, Victor H.

    2005-04-01

    A goal of our laboratory is to accurately define the parameters of light dose and drug dose that contribute to tissue destruction after Photodynamic therapy (PDT). Using Photofrin as sensitizer, we examined a range of drug doses, various intervals between injection and light treatment, and various fluence rates. The effect of Photofrin photosensitizer encapsulated in liposomal delivery vehicle was also studied. Three liposome delivery vehicles were chosen to deliver the photosensitizer in vivo: DPPC/cholesterol, DMPC/HPC and stealth liposomes. Tumor response and microvessel behaviour were examined in tumor and surrounding skin in a mouse model. Under these conditions, better selectivity of tissue damage was seen using some of the treatment. These data might be used to design better clinical protocols for patient care. In memory of Dr. Victor Fingar (Supported by R01 CA51771).

  19. Effects of varied doses of psilocybin on time interval reproduction in human subjects.

    PubMed

    Wackermann, Jirí; Wittmann, Marc; Hasler, Felix; Vollenweider, Franz X

    2008-04-11

    Action of a hallucinogenic substance, psilocybin, on internal time representation was investigated in two double-blind, placebo-controlled studies: Experiment 1 with 12 subjects and graded doses, and Experiment 2 with 9 subjects and a very low dose. The task consisted in repeated reproductions of time intervals in the range from 1.5 to 5s. The effects were assessed by parameter kappa of the 'dual klepsydra' model of internal time representation, fitted to individual response data and intra-individually normalized with respect to initial values. The estimates kappa were in the same order of magnitude as in earlier studies. In both experiments, kappa was significantly increased by psilocybin at 90 min from the drug intake, indicating a higher loss rate of the internal duration representation. These findings are tentatively linked to qualitative alterations of subjective time in altered states of consciousness.

  20. The effect of sampling rate on observed statistics in a correlated random walk

    PubMed Central

    Rosser, G.; Fletcher, A. G.; Maini, P. K.; Baker, R. E.

    2013-01-01

    Tracking the movement of individual cells or animals can provide important information about their motile behaviour, with key examples including migrating birds, foraging mammals and bacterial chemotaxis. In many experimental protocols, observations are recorded with a fixed sampling interval and the continuous underlying motion is approximated as a series of discrete steps. The size of the sampling interval significantly affects the tracking measurements, the statistics computed from observed trajectories, and the inferences drawn. Despite the widespread use of tracking data to investigate motile behaviour, many open questions remain about these effects. We use a correlated random walk model to study the variation with sampling interval of two key quantities of interest: apparent speed and angle change. Two variants of the model are considered, in which reorientations occur instantaneously and with a stationary pause, respectively. We employ stochastic simulations to study the effect of sampling on the distributions of apparent speeds and angle changes, and present novel mathematical analysis in the case of rapid sampling. Our investigation elucidates the complex nature of sampling effects for sampling intervals ranging over many orders of magnitude. Results show that inclusion of a stationary phase significantly alters the observed distributions of both quantities. PMID:23740484

  1. Training effects on endurance capacity in maximal intermittent exercise: comparison between continuous and interval training.

    PubMed

    Tanisho, Kei; Hirakawa, Kazufumi

    2009-11-01

    The purpose of this study was to examine the effects of 2 different training regimens, continuous (CT) and interval (IT), on endurance capacity in maximal intermittent exercise. Eighteen lacrosse players were divided into CT (n = 6), IT (n = 6), and nontraining (n = 6) groups. Both training groups trained for 3 days per week for 15 weeks using bicycle ergometers. Continuous training performed continuous aerobic training for 20-25 minutes, and IT performed high-intensity pedaling comprising 10 sets of 10-second maximal pedaling with 20-second recovery periods. Maximal anaerobic power, maximal oxygen uptake (V(O2max)), and intermittent power output were measured before and after the training period. The intermittent exercise test consisted of a set of ten 10-second maximal sprints with 40-second intervals. Maximal anaerobic power significantly increased in IT (p effect on high-power endurance capacity in maximal intermittent exercise. In contrast, although lactate production did not decrease, IT improved fatigability and mean power output in the last stage. These results indicated that the endurance capacities for maximal intermittent and continuous exercises were not identical. Ball game players should therefore improve their endurance capacity with high-intensity intermittent exercise, and it is insufficient to assess their capacity with only V(O2max) or continuous exercise tests.

  2. Inhibitory effect of intensity and interstimulus interval of conditioning stimuli on somatosensory evoked magnetic fields.

    PubMed

    Onishi, Hideaki; Sugawara, Kazuhiro; Yamashiro, Koya; Sato, Daisuke; Kirimoto, Hikari; Tamaki, Hiroyuki; Shirozu, Hiroshi; Kameyama, Shigeki

    2016-08-01

    Magnetoencephalography (MEG) recordings were performed to investigate the inhibitory effects of conditioning stimuli with various types of interstimulus intervals (ISIs) or intensities on somatosensory evoked magnetic fields (SEFs) using a 306-ch whole-head MEG system. Twenty-three healthy volunteers participated in this study. Electrical stimuli were applied to the right median nerve at the wrist. Six pulse trains with ISIs of 500 ms were presented in Experiment 1. A paired-pulse paradigm with three kinds of conditioning stimulus (CON) intensities, 500 ms before the test stimulus (TS), was applied in Experiment 2. Finally, three CONs 500 or 1000 ms before TS were presented in Experiment 3. Three main SEF deflections (N20m, P35m, and P60m) were observed, and the source activities of P35m and P60m significantly decreased after the 2nd pulse of a six pulse trains. These source activities also significantly decreased with increasing intensity of CON. In addition, these attenuations of source activities were affected by CON-CON or CON-TS intervals. These results indicated that the source activities were modulated by the intensity and ISIs of CONs. Furthermore, P35m after the stimulation were very sensitive to CONs; however, the attenuation of P60m after the stimulation lasted for a longer period than that of P35m. Our findings suggest that the conditioning stimulation had inhibitory effects on subsequent evoked cortical responses for more than 500 ms. Our results also provide important clues about the nature of short-latency somatosensory responses in human studies. PMID:27319980

  3. Effects of Simultaneous or Sequential Weight Loss Diet and Aerobic Interval Training on Metabolic Syndrome.

    PubMed

    Mora-Rodriguez, R; Ortega, J F; Guio de Prada, V; Fernández-Elías, V E; Hamouti, N; Morales-Palomo, F; Martinez-Vizcaino, V; Nelson, R K

    2016-04-01

    Our purpose in this study was to investigate efficient and sustainable combinations of exercise and diet-induced weight loss (DIET), in order to combat obesity in metabolic syndrome (MetS) patients. We examined the impact of aerobic interval training (AIT), followed by or concurrent to a DIET on MetS components. 36 MetS patients (54±9 years old; 33±4 BMI; 27 males and 9 females) underwent 16 weeks of AIT followed by another 16 weeks without exercise from the fall of 2013 to the spring of 2014. Participants were randomized to AIT without DIET (E CON, n=12), AIT followed by DIET (E-then-D, n=12) or AIT concurrent with DIET (E+D, n=12) groups. Body weight decreased below E CON similarly in the E-then-D and E+D groups (~5%). Training improved blood pressure and cardiorespiratory fitness (VO2peak) in all groups with no additional effect of concurrent weight loss. However, E+D improved insulin sensitivity (HOMA) and lowered plasma triglycerides and blood cholesterol below E CON and E-then-D (all P<0.05). Weight loss in E-then-D in the 16 weeks without exercise lowered HOMA to the E+D levels and maintained blood pressure at trained levels. Our data suggest that a new lifestyle combination consisting of aerobic interval training followed by weight loss diet is similar, or even more effective on improving metabolic syndrome factors than concurrent exercise plus diet.

  4. Effect of propranolol on the QT intervals of normal individuals during exercise: a new method for studying interventions.

    PubMed Central

    Sarma, J S; Venkataraman, K; Samant, D R; Gadgil, U G

    1988-01-01

    A new method was used to study the effect of a single dose of propranolol on the QT intervals during exercise in 11 normal volunteers. They exercised maximally on a bicycle ergometer and repeated the test after taking propranolol (40 mg) by mouth two hours before. Electrocardiograms were continuously recorded on magnetic tape and the cardiac cycle length (RR interval) and the QT interval were measured every five seconds by a computer aided method. The RR-QT data from each test during the exercise phase were analysed by an exponential formula, QT = A - B x exp (-k x RR) and by Bazett's formula, QT = K x square root of (RR). Three reference QT intervals, QTc1, QTc2, and QTc3, estimated at RR = 400, 700, and 1000 ms respectively from the regression curves of both formulas were compared. The exponential formula, which consistently gave a better fit with the data, showed that propranolol had a biphasic action on the QT intervals during exercise. It significantly prolonged the mean (SD) interval at longer cycle lengths (from 287 (27) to 305 (18) ms at RR = 1000 ms and shortened it at shorter cycle lengths (from 198 (14) to 179 (16) ms at RR = 400 ms). In contrast, Bazett's formula did not show any significant effect when the same raw data were used. The exponential formula can be adapted to study other interventions or conditions that affect QT intervals. PMID:3203038

  5. Interval Training.

    ERIC Educational Resources Information Center

    President's Council on Physical Fitness and Sports, Washington, DC.

    Regardless of the type of physical activity used, interval training is simply repeated periods of physical stress interspersed with recovery periods during which activity of a reduced intensity is performed. During the recovery periods, the individual usually keeps moving and does not completely recover before the next exercise interval (e.g.,…

  6. The Effect Of Shifts In Fixed-Interval Schedules On Acquisition, Extinction, Spontaneous Recovery, And Reacquisition.

    PubMed

    Nath Mukherjee, B

    1967-10-01

    Using both multivariate and univariate statistical tests, the effect of two opposite patterns of primary reinforcement schedules upon the acquisition, extinction, spontaneous recovery and reacquisition of bar pressing was determined. Two control and two experimental groups, each consisting of eight Ss, formed the standard 2x2 factorial design for the experiment. The main effects were (a) effect of primary reinforcement (experimental vs. control groups) and (b) direction of shift in the schedule values (ascending vs. descending groups). The extinction data showed that the experimental group exposed to the ascending-order shift pressed the bar more than the descending group. Therefore, persistence of nonreinforced responding is a function of the direction of shift in fixed-interval values. The recovery data for first day indicated that primary reinforcements following either pattern facilitated spontaneous recovery. However, on second day neither direction of shift nor primary reinforcement had any significant effect on it. Covariance analysis of recovery and reacquisition data for second day revealed that the experimental ascending group showed better recovery and reacquisition when the frequency of prior nonreinforced responding was held constant. The SL analyses suggest a higher acquisition level for the experimental ascending group than for the other groups. It is possible to explain the result in terms of Hull's habit- strength theory.

  7. Mood and selective attention in the cold: the effect of interval versus continuous exercise.

    PubMed

    Muller, Matthew D; Muller, Sarah M; Kim, Chul-Ho; Ryan, Edward J; Gunstad, John; Glickman, Ellen L

    2011-07-01

    Both mood and cognitive function are altered in cold environments. Body warming through exercise may improve Stroop interference score and lessen total negative mood. The purpose of this study was to determine the effect of equal caloric bouts of interval (INT) and continuous (CONT) exercise on mood and selective attention in the cold. Eleven young men underwent two experimental trials in 5°C air. Both trials consisted of 90 min acute cold exposure (ACE), 30 min exercise (INT vs. CONT), and 60 min recovery (REC). The Profile of Mood States (POMS) and Stroop Color Word Test (SCWT) were administered at four time points. Mean body temperature decreased during ACE, increased during exercise, and decreased during REC. Repeated measures analysis of variance revealed a main effect for time for several of the POMS sub scores. In particular, negative mood was significantly decreased after exercise relative to ACE and then significantly increased during REC. Further, CONT appears to be more effective than INT at decreasing negative mood. Components of the SCWT supported both the arousal and distraction theories for simple perception, but no significant effects were shown for the interference score. In the cold, exercise decreases negative mood but does not appear to affect selective attention. Further mechanistic studies could determine the best mode and intensity of exercise for improving cognitive function in the cold. PMID:21152931

  8. Cumulative Instructional Time and Relative Effectiveness Conclusions: Extending Research on Response Intervals, Learning, and Measurement Scale.

    PubMed

    Black, Michelle P; Skinner, Christopher H; Forbes, Bethany E; McCurdy, Merilee; Coleman, Mari Beth; Davis, Kristie; Gettelfinger, Maripat

    2016-03-01

    Adapted alternating treatments designs were used to evaluate three computer-based flashcard reading interventions (1-s, 3-s, or 5-s response intervals) across two students with disabilities. When learning was plotted with cumulative instructional sessions on the horizontal axis, the session-series graphs suggest that the interventions were similarly effective. When the same data were plotted as a function of cumulative instructional seconds, time-series graphs suggest that the 1-s intervention caused the most rapid learning for one student. Discussion focuses on applied implications of comparative effectiveness studies and why measures of cumulative instructional time are needed to identify the most effective intervention(s).Comparative effectiveness studies may not identify the intervention which causes the most rapid learning.Session-series repeated measures are not the same as time-series repeated measures.Measuring the time students spend in each intervention (i.e., cumulative instructional seconds) allows practitioners to identify interventions that enhance learning most rapidly.Student time spent working under interventions is critical for drawing applied conclusions. PMID:27606240

  9. Effects of unsignaled delays of reinforcement on fixed-interval schedule performance.

    PubMed

    Elcoro, Mirari; Lattal, Kennon A

    2011-09-01

    Key pecking of pigeons was maintained by a fixed-interval (FI) 61-s schedule. The effects of resetting and nonresetting unsignaled delays of reinforcement then were examined. The resetting delay was programmed as a differential-reinforcement-of-other-behavior schedule, and the nonresetting delay as a fixed-time schedule. Three delay durations (0.5, 1 and 10s) were examined. Overall response rates were decreased by one and 10-s delays and increased by 0.5-s delays. Response patterns changed from positively accelerated to more linear when resetting or nonresetting 10-s delays were imposed, but remained predominantly positively accelerated when resetting and nonresetting 0.5- and 1-s delays were in effect. In general, temporal control, as measured by quarter-life values, changed less than overall response rates when delays of reinforcement were in effect. The response patterns controlled by FI schedules are more resilient to the nominally disruptive effects of delays of reinforcement than are corresponding overall response rates.

  10. Effect of intense interval workouts on running economy using three recovery durations.

    PubMed

    Zavorsky, G S; Montgomery, D L; Pearsall, D J

    1998-02-01

    The purposes of this study were to determine whether running economy (RE) is adversely affected following intense interval bouts of 10 x 400-m running, and whether there is an interaction effect between RE and recovery duration during the workouts. Twelve highly trained male endurance athletes [maximal oxygen consumption; VO2max = 72.5 (4.3) ml x kg(-1) x min(-1) mean (SD)] performed three interval running workouts of 10 x 400 m with a minimum of 4 days between runs. Recovery duration between the repetitions was randomly assigned at 60, 120 or 180 s. The velocity for each 400-m run was determined from a treadmill VO2max test. The average running velocity was 357.9 (9.0) m x min(-1). Following the workout, the rating of perceived exertion (RPE) increased significantly (P < 0.01) as recovery duration between the 400-m repetitions decreased (14.4, 16.1, and 17.7 at 180s, 120s, and 60 s recovery, respectively). Prior to and following each workout, RE was measured at speeds of 200 and 268 m x min(-1). Changes in RE from pre- to post-workout, as well as heart rate (HR) and respiratory exchange ratio (R) were similar for the three recovery conditions. When averaged across conditions, oxygen consumption (VO2) increased significantly (P < 0.01) from pre- to post-test [from 38.5 to 40.5 ml x kg(-1) x min(-1) at 200 m x min(-1), and from 53.1 to 54.5 ml x kg(-1) x min(-1) at 268 m x min(-1), respectively]. HR increased (from 124 to 138, and from 151 to 157 beats x min(-1) respectively) and R decreased (from 0.90 to 0.78, and from 0.93 to 0.89, respectively) at 200 and 268 m x min(-1), respectively (P < 0.01). This study showed that RE can be perturbed after a high-intensity interval workout and that the changes in VO2, HR and R were independent of the recovery duration between the repetitions.

  11. Effect of adenosine triphosphate on left atrial electrogram interval and dominant frequency in human atrial fibrillation☆

    PubMed Central

    Kogawa, Rikitake; Okumura, Yasuo; Watanabe, Ichiro; Kofune, Masayoshi; Nagashima, Koichi; Mano, Hiroaki; Sonoda, Kazumasa; Sasaki, Naoko; Iso, Kazuki; Takahashi, Keiko; Ohkubo, Kimie; Nakai, Toshiko; Hirayama, Atsushi

    2015-01-01

    Background Complex fractionated atrial electrograms (CFAEs) and high dominant frequency (DF) are targets for atrial fibrillation (AF) ablation. Although adenosine triphosphate (ATP) is known to promote AF by shortening the atrial refractory period, its role in the pathogenesis of CFAEs and DF during AF is not fully understood. Methods We recorded electrical activity from a 64-electrode basket catheter placed in the left atrium (LA) of patients with paroxysmal AF (PAF, n=18) or persistent AF (PerAF, n=19) before ablation. Atrial electrogram fractionation intervals (FIs) and DFs were measured from bipolar electrograms of each adjacent electrode pair. Offline mean atrial FIs and DFs were obtained before bolus injection of 30 mg ATP. Peak effect was defined as an R–R interval >3 s. Results With ATP, the mean FI decreased (from 110.4±29.1 ms to 90.5±24.7 ms, P<0.0001) and DF increased (from 6.4±0.6 Hz to 7.1±0.8 Hz, P<0.0001) in all patients. There was no difference in the FI decrease between the two groups (−20.3±20.5 ms vs. −19.6±14.5 ms, P=0.6032), but the increase in DF was significantly greater in PAF patients (1.1±0.8 Hz vs. 0.3±0.6 Hz, P=0.0051). Conclusions ATP shortens atrial FIs and increases DFs in both PAF and PerAF patients. The significant increase in DF in PAF patients suggests that pathophysiologic characteristics related to the frequency of atrial fractionation change as atrial remodeling progresses. PMID:26702319

  12. Effects of Paradigm and Inter-Stimulus Interval on Age Differences in Eyeblink Classical Conditioning in Rabbits

    ERIC Educational Resources Information Center

    Woodruff-Pak, Diana S.; Seta, Susan E.; Roker, LaToya A.; Lehr, Melissa A.

    2007-01-01

    The aim of this study was to examine parameters affecting age differences in eyeblink classical conditioning in a large sample of young and middle-aged rabbits. A total of 122 rabbits of mean ages of 4 or 26 mo were tested at inter-stimulus intervals (ISIs) of 600 or 750 msec in the delay or trace paradigms. Paradigm affected both age groups…

  13. Bouts of Responding on Variable-Interval Schedules: Effects of Deprivation Level

    ERIC Educational Resources Information Center

    Shull, Richard L.

    2004-01-01

    Rats obtained food pellets on a variable-interval schedule of reinforcement by nose poking a lighted key. After training to establish baseline performance (with the mean variable interval set at either 60, 120, or 240 s), the rats were given free access to food during the hour just before their daily session. This satiation operation reduced the…

  14. Effect of sample size in the evaluation of "in-field" sampling plans for aflatoxin B(1) determination in corn.

    PubMed

    Brera, Carlo; De Santis, Barbara; Prantera, Elisabetta; Debegnach, Francesca; Pannunzi, Elena; Fasano, Floriana; Berdini, Clara; Slate, Andrew B; Miraglia, Marina; Whitaker, Thomas B

    2010-08-11

    Use of proper sampling methods throughout the agri-food chain is crucial when it comes to effectively detecting contaminants in foods and feeds. The objective of the study was to estimate the performance of sampling plan designs to determine aflatoxin B(1) (AFB(1)) contamination in corn fields. A total of 840 ears were selected from a corn field suspected of being contaminated with aflatoxin. The mean and variance among the aflatoxin values for each ear were 10.6 mug/kg and 2233.3, respectively. The variability and confidence intervals associated with sample means of a given size could be predicted using an equation associated with the normal distribution. Sample sizes of 248 and 674 ears would be required to estimate the true field concentration of 10.6 mug/kg within +/-50 and +/-30%, respectively. Using the distribution information from the study, operating characteristic curves were developed to show the performance of various sampling plan designs.

  15. Intertrial intervals and contextual conditioning in appetitive pavlovian learning: effects over the ABA renewal paradigm.

    PubMed

    Carranza-Jasso, Rodrigo; Urcelay, Gonzalo P; Nieto, Javier; Sánchez-Carrasco, Livia

    2014-09-01

    Three experiments using rats in an appetitive conditioning procedure analyzed the effect of short and long (50s vs. 1440s) intertrial intervals (ITI) over the acquisition of conditioned stimulus (CS), context (Ctxt), and unconditioned stimulus (US) associations, as well as the effect on the extinction and renewal of the conditioned response to the CS. Experiment 1 revealed more contextual conditioned responses in groups trained with the short ITIs, however the renewal effect was not observed during test phase with either ITI condition. When subjects were pre-exposed to the contexts before the acquisition phase (Experiment 2) renewal of the conditioned response (CR) was only observed in long ITI group. However, when the acquisition context was extinguished (Experiment 3) the renewal effect observed in the Experiment 2 was weakened. In all three experiments subjects showed a similar number of responses to the tone predicting food, however they showed a clear contextual conditioning effect only for the groups trained with short ITIs. It is noteworthy that the acquisition context showed high levels of the CR in the renewal test only for groups trained with short ITIs (Experiment 2) but these responses were absent if additional contextual extinction was imposed before such test (Experiment 3). In general, all groups showed similar acquisition curves for the CS but only Short groups had an increase in the CR during the pre-CS. Also, context conditioning does not interfere with the conditioning of the CS and context pre-exposure prior to acquisition is essential in order to observe the renewal effect when long ITIs are used.

  16. Effects of rotation interval on sleepiness and circadian dynamics on forward rotating 3-shift systems.

    PubMed

    Postnova, Svetlana; Postnov, Dmitry D; Seneviratne, Martin; Robinson, Peter A

    2014-02-01

    A physiologically based mathematical model of sleep-wake cycles is used to examine the effects of shift rotation interval (RI) (i.e., the number of days spent on each shift) on sleepiness and circadian dynamics on forward rotating 3-shift schedules. The effects of the schedule start time on the mean shift sleepiness are also demonstrated but are weak compared to the effects of RI. The dynamics are studied for a parameter set adjusted to match a most common natural sleep pattern (i.e., sleep between 0000 and 0800) and for common light conditions (i.e., 350 lux of shift lighting, 200 lux of daylight, 100 lux of artificial lighting during nighttime, and 0 lux during sleep). Mean shift sleepiness on a rotating schedule is found to increase with RI, reach maximum at intermediate RI=6 d, and then decrease. Complete entrainment to shifts within the schedules is not achieved at RI≤10 d. However, circadian oscillations synchronize to the rotation cycles, with RI=1,2 d and RI≥6 d demonstrating regular periodic changes of the circadian rhythm. At rapid rotation, circadian phase stays within a small 4-h interval, whereas slow rotation leads to around-the-clock transitions of the circadian phase with constantly delayed sleep times. Schedules with RI=3-5 d are not able to entrain the circadian rhythms, even in the absence of external circadian disturbances like social commitments and days off. To understand the circadian dynamics on the rotating shift schedules, a shift response map is developed, showing the direction of circadian change (i.e., delay or advance) depending on the relation between the shift start time and actual circadian phase. The map predicts that the un-entrained dynamics come from multiple transitions between advance and delay behavior on the shifts in the schedules. These are primarily caused by the imbalance between the amount of delay and advance on the different shift types within the schedule. Finally, it is argued that shift response maps can aid in

  17. Confidence Intervals for the Probability of Superiority Effect Size Measure and the Area under a Receiver Operating Characteristic Curve

    ERIC Educational Resources Information Center

    Ruscio, John; Mullen, Tara

    2012-01-01

    It is good scientific practice to the report an appropriate estimate of effect size and a confidence interval (CI) to indicate the precision with which a population effect was estimated. For comparisons of 2 independent groups, a probability-based effect size estimator (A) that is equal to the area under a receiver operating characteristic curve…

  18. Atropine unmasks bed-rest effect - A spectral analysis of cardiac interbeat intervals

    NASA Technical Reports Server (NTRS)

    Goldberger, Ary L.; Goldwater, Danielle; Bhargava, Valmik

    1986-01-01

    Heart rate spectral data obtained for 10 male subjects between 35-49 years following orthostatic tolerance testing with lower body negative pressure prebed rest and after 7-10 days of bed rest, while on placebo and after intravenous atropine are analyzed. Comparison of the spectral atropine rms for subjects prebed rest and after bed rest reveal a decrease from 63 + or - 24 ms to 40 + or - 23 ms. It is observed that heart rate interval variability for subjects after bed rest and with atropine is reduced; the heart rate at bed rest with atropine is increased from 70.4 + or - 12.4 beats/min prebed rest to 83.7 + or - 18.9 beats/min; and the exercise tolerance time for subjects in the atropine prebed-rest phase (658 + or - 352 s) is higher than the bed-rest phase (505 + or - 252 s). It is noted that bed rest impairs the cardiovascular capacity to adaptively modulate physiological responses, atropine exposes bed-rest deconditioning effects, and spectral analysis is useful for studying the effects of bed-rest deconditioning on cardiac dynamics.

  19. Effects of high-intensity interval vs. continuous moderate exercise on intraocular pressure.

    PubMed

    Conte, M; Baldin, A D; Russo, M R R R; Storti, L R; Caldara, A A; Cozza, H F P; Ciolac, E G

    2014-09-01

    Our purpose was to compare the acute effects of high-intensity interval training (HIT) vs. continuous moderate exercise (CME) on intraocular pressure (IOP) in healthy subjects. Fifteen young men (age=22.1±6 years) underwent 30 min of HIT (2 min of walking at 50% of reserve heart rate (HR) alternated with 1 min of running at 80% of reserve HR) and CME sessions (30 min of jogging/running at 60% of reserve HR) in random order (2-5 days between sessions). IOP was measured before (baseline), immediately after (post--exercise), 5 min after (Rec5) and 10 min after (Rec10) each exercise session. IOP was reduced post-exercise and remained reduced at Rec5 during both HIT and CME session, with no significant difference between interventions (~16% between 23%). However, IOP remained reduced at Rec10 only after HIT intervention (~19%), whereas IOP at Rec10 returned to levels similar to the observed at baseline during CME intervention. In summary, both HIT and CME equally reduced IOP immediately and 5 min after exercise session. However, only HIT was able to remain IOP reduced 10 min after exercise. These results suggest that HIT may be more effective than CME for reducing IOP in young healthy men.

  20. Effect of Interval to Definitive Breast Surgery on Clinical Presentation and Survival in Early-Stage Invasive Breast Cancer

    SciTech Connect

    Vujovic, Olga; Yu, Edward; Cherian, Anil; Perera, Francisco; Dar, A. Rashid; Stitt, Larry; Hammond, A.

    2009-11-01

    Purpose: To examine the effect of clinical presentation and interval to breast surgery on local recurrence and survival in early-stage breast cancer. Methods and Materials: The data from 397 patients with Stage T1-T2N0 breast carcinoma treated with conservative surgery and breast radiotherapy between 1985 and 1992 were reviewed at the London Regional Cancer Program. The clinical presentation consisted of a mammogram finding or a palpable lump. The intervals from clinical presentation to definitive breast surgery used for analysis were 0-4, >4-12, and >12 weeks. The Kaplan-Meier estimates of the time to local recurrence, disease-free survival, and cause-specific survival were determined for the three groups. Cox regression analysis was used to evaluate the effect of clinical presentation and interval to definitive surgery on survival. Results: The median follow-up was 11.2 years. No statistically significant difference was found in local recurrence as a function of the interval to definitive surgery (p = .424). A significant difference was noted in disease-free survival (p = .040) and cause-specific survival (p = .006) with an interval of >12 weeks to definitive breast surgery. However, the interval to definitive surgery was dependent on the presentation for cause-specific survival, with a substantial effect for patients with a mammographic presentation and a negligible effect for patients with a lump presentation (interaction p = .041). Conclusion: The results of this study suggest that an interval of >12 weeks to breast surgery might be associated with decreased survival for patients with a mammographic presentation, but it appeared to have no effect on survival for patients presenting with a palpable breast lump.

  1. Temporal Learning and Rhythmic Responding: No Reduction in the Proportion Easy Effect with Variable Response-Stimulus Intervals

    PubMed Central

    Schmidt, James R.

    2016-01-01

    The present report further investigates the proportion easy effect, a conflict-free version of the proportion congruent effect. In the proportion easy paradigm, it is observed that the difference in performance between easy (high contrast) and hard (low contrast) items is smaller in a task with mostly hard items relative to a task with mostly easy items. This effect has been interpreted as evidence for temporal learning: participants learn a faster pace (i.e., rhythm of responding) in the mostly easy context, which boosts the contrast effect, and a slower pace in the mostly hard context. In the present experiment, intervals between trials were either fixed or randomly varied from trial to trial. Interestingly, the proportion easy effect was still present with variable intervals. These data suggest that participants do not learn the regularity in timing from one response to the next (which was highly inconsistent with variable intervals). As one alternative, participants might be learning the intervals between stimulus onset and responses, which were not manipulated. They could then use this learned timing information to prepare for responding at the anticipated time, resulting in rhythmic responding. The results further imply that variable response-stimulus intervals are insufficient for controlling for rhythmic biases. PMID:27199861

  2. The effect of footwear and footfall pattern on running stride interval long-range correlations and distributional variability.

    PubMed

    Fuller, Joel T; Amado, Avelino; Emmerik, Richard E A van; Hamill, Joseph; Buckley, Jonathan D; Tsiros, Margarita D; Thewlis, Dominic

    2016-02-01

    The presence of long-range correlations (self-similarity) in the stride-to-stride fluctuations in running stride interval has been used as an indicator of a healthy adaptable system. Changes to footfall patterns when running with minimalist shoes could cause a less adaptable running gait. The purpose of this study was to investigate stride interval variability and the degree of self-similarity of stride interval in runners wearing minimalist and conventional footwear. Twenty-six trained habitual rearfoot footfall runners, unaccustomed to running in minimalist footwear, performed 6-min sub-maximal treadmill running bouts at 11, 13 and 15 km·h(-1) in minimalist and conventional shoes. Force sensitive resistors were placed in the shoes to quantify stride interval (time between successive foot contacts). Footfall position, stride interval mean and coefficient of variation (CV), were used to assess performance as a function of shoe type. Long-range correlations of stride interval were assessed using detrended fluctuation analysis (α). Mean stride interval was 1-1.3% shorter (P=0.02) and 27% of runners adopted a midfoot footfall (MFF) in the minimalist shoe. There was a significant shoe effect on α and shoe*speed*footfall interaction effect on CV (P<0.05). Runners that adopted a MFF in minimalist shoes, displayed reduced long-range correlations (P<0.05) and CV (P<0.06) in their running stride interval at the 15 km·h(-1) speed. The reduced variability and self-similarity observed for runners that changed to a MFF in the minimalist shoe may be suggestive of a system that is less flexible and more prone to injury. PMID:27004647

  3. Effect of vitamin E succinate on inflammatory cytokines induced by high-intensity interval training

    PubMed Central

    Sarir, Hadi; Emdadifard, Ghodsieh; Farhangfar, Homayoun; TaheriChadorneshin, Hossein

    2015-01-01

    Aim and Scope: The anti-inflammatory effect of vitamin E under moderate exercises has been evaluated. However, the effect of vitamin E succinate, which has more potent anti-inflammatory effect than other isomers of vitamin E has not been evaluated. Therefore, the aim of the present study was to evaluate the effects of vitamin E succinate on tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6) production induced by high-intensity interval training (HIIT). Materials and Methods: In the present study, 24 rats were randomly divided into control (C), supplementation (S), HIIT, and HIIT + supplementation (HIIT+S) groups. HIIT training protocol on a treadmill (at a speed of 40–54 m/min) and vitamin E succinate supplementation (60 mg/kg/day) was conducted for 6 weeks. Results: Serum IL-6 in the HIIT group significantly increased compared with the C group (350.42 ± 123.31 pg/mL vs 158.60 ± 41.96 pg/mL; P = 0.002). Also, serum TNF-α concentrations significantly enhanced (718.15 ± 133.42 pg/mL vs 350.87 ± 64.93 pg/mL; P = 0.001) in the HIIT group compared with the C group. Treatment of the training group with vitamin E numerically reduced IL-6 and TNF-α when compared with the HIIT group (217.31 ± 29.21 and 510.23 ± 217.88, respectively, P > 0.05). However, no significant changes were observed in serum TNF-α (P = 0.31) and IL-6 (P = 0.52) concentrations in the HIIT + S group compared with the C group. Conclusion: HIIT-induced IL-6 and TNF-α decreased by administration of Vitamin E succinate. PMID:26958053

  4. Arsenic Exposure from Drinking Water and QT-Interval Prolongation: Results from the Health Effects of Arsenic Longitudinal Study

    PubMed Central

    Wu, Fen; Parvez, Faruque; Ahmed, Alauddin; Eunus, Mahbub; McClintock, Tyler R.; Patwary, Tazul Islam; Islam, Tariqul; Ghosal, Anajan Kumar; Islam, Shahidul; Hasan, Rabiul; Levy, Diane; Sarwar, Golam; Slavkovich, Vesna; van Geen, Alexander; Graziano, Joseph H.

    2013-01-01

    Background: Arsenic exposure from drinking water has been associated with heart disease; however, underlying mechanisms are uncertain. Objective: We evaluated the association between a history of arsenic exposure from drinking water and the prolongation of heart rate–corrected QT (QTc), PR, and QRS intervals. Method: We conducted a study of 1,715 participants enrolled at baseline from the Health Effects of Arsenic Longitudinal Study. We assessed the relationship of arsenic exposure in well water and urine samples at baseline with parameters of electrocardiogram (ECG) performed during 2005–2010, 5.9 years on average since baseline. Results: The adjusted odds ratio (OR) for QTc prolongation, defined as a QTc ≥ 450 msec in men and ≥ 460 msec in women, was 1.17 (95% CI: 1.01, 1.35) for a 1-SD increase in well-water arsenic (108.7 µg/L). The positive association appeared to be limited to women, with adjusted ORs of 1.24 (95% CI: 1.05, 1.47) and 1.24 (95% CI: 1.01, 1.53) for a 1-SD increase in baseline well-water and urinary arsenic, respectively, compared with 0.99 (95% CI: 0.73, 1.33) and 0.86 (95% CI: 0.49, 1.51) in men. There were no apparent associations of baseline well-water arsenic or urinary arsenic with PR or QRS prolongation in women or men. Conclusions: Long-term arsenic exposure from drinking water (average 95 µg/L; range, 0.1–790 µg/L) was associated with subsequent QT-interval prolongation in women. Future longitudinal studies with repeated ECG measurements would be valuable in assessing the influence of changes in exposure. PMID:23384555

  5. Effects of autonomous motivational priming on motivation and affective responses towards high-intensity interval training.

    PubMed

    Brown, Denver M Y; Teseo, Amanda J; Bray, Steven R

    2016-08-01

    This study examined the effect of autonomous motivational priming on motivation, attitudes and intentions towards high-intensity interval training (HIT). Participants (N = 42) performed a graded exercise test to determine their peak aerobic power (WPEAK). At a subsequent testing session, participants were randomised to complete either an autonomous or neutral motivational priming task followed by a 10 × 1 HIT exercise protocol, alternating 1-min bouts of hard (70% WPEAK) and light (12.5% WPEAK) exercises for 20 min. Participants primed with autonomous motivation reported greater enjoyment, P = .009, ηp(2) = .16, and perceived competence, P = .005, ηp(2) = .18, post-exercise compared to those in the neutral priming condition. Participants in the autonomous motivational priming condition also reported more positive attitudes, P = .014, ηp(2) = .14, towards HIT; however, there was no difference between the conditions for task motivation during HIT or intentions, P = .53, ηp(2) = .01, to engage in HIT. These findings highlight autonomous motivational priming as a method of enhancing affective and motivational experiences regarding HIT.

  6. Interval breast cancers in screening: the effect of mammography review method on classification.

    PubMed

    Ciatto, Stefano; Catarzi, Sandra; Lamberini, Maria Perla; Risso, Gabriella; Saguatti, Gianni; Abbattista, Teresa; Martinelli, Francesca; Houssami, Nehmat

    2007-12-01

    Surveillance of interval cancers (IC) lacks standardisation of review methodologies. We investigated the extent to which 'informed' or 'blinded' review may affect IC classification. This is a retrospective study of 100 validated screening mammograms (20 IC, 80 negative screens) independently reviewed by six radiologists. Three sequenced review methods with increasing information were used: (1) blinded (no IC information, case mix), (2) partially informed, and (3) fully informed. IC 'screening error' (SE) reports averaged 24% (10-40), 33% (20-55), and 42% (35-50) for phases 1, 2, and 3, while 'minimal signs' (MS) reports averaged 6% (5-15), 10% (10-20), and 20% (15-30), respectively. Negative mammograms classification was MS in 18% (7-39) or SE in 19% (11-29), respectively. MS or SE classification was more likely for method 2 (OR=1.78, p=0.033) and method 3 (OR=3.91, p=0.000) relative to method 1, but no reader effect was evident. Inter-observer agreement in classifying at method 1 was slight (k 0.20), lowest (k 0.06) for MS, and fair (k 0.25) for negative and SE categories. More 'informed' review is more likely to yield an IC classification as MS or SE. Due to expected variability, review methods need standardisation to improve screening quality. Our data support blinded review of IC in mammography screening.

  7. Effects of changes in frequency on guinea pig ventricular action potential duration and on QT interval under different experimental conditions.

    PubMed

    von Savigny, L; Hohnloser, S; Antoni, H

    1981-01-01

    Isolated perfused guinea pig hearts (Langendorff preparation) were arrested by carbachol (0.1-0.2 mg/l) and electrically stimulated in the region of the av-conducting system. The QT interval was determined by means of extracellular electrodes at different driving frequencies. Separate experiments were performed on papillary muscles from the right ventricle to measure the duration of the transmembrane action potential under comparable conditions. At 35 degrees C (Ke+ 5.4 mmol/l) increasing the frequency of stimulation (range 12-120/min) caused the action potential duration (APD) to decrease to a greater extent than the QT interval. Stepwise rising of the external K+ concentration up to 16.2 mmol/l produced a nearly parallel shift to the APD-frequency relation to lower values. Again, the QT interval was less affected by increasing the external K+ concentration than the APD. Stepwise reduction of the temperature down to 20 degrees C prolonged the APD as well as the QT interval, the effects being more pronounced at lower than at higher stimulation frequencies. Under all examined experimental conditions, the APD proved to be markedly shorter than the QT interval even when the latter is diminished by the duration of QRS. The results suggest that no close relation exists between the APD and the QT interval. The observed divergencies may be due to functional differences among various parts of the ventricles.

  8. The effects of intervening interference on working memory for sound location as a function of inter-comparison interval.

    PubMed

    Ries, Dennis T; Hamilton, Traci R; Grossmann, Aurora J

    2010-09-01

    This study examined the effects of inter-comparison interval duration and intervening interference on auditory working memory (AWM) for auditory location. Interaural phase differences were used to produce localization cues for tonal stimuli and the difference limen for interaural phase difference (DL-IPD) specified as the equivalent angle of incidence between two sound sources was measured in five different conditions. These conditions consisted of three different inter-comparison intervals [300 ms (short), 5000 ms (medium), and 15,000 ms (long)], the medium and long of which were presented both in the presence and absence of intervening tones. The presence of intervening stimuli within the medium and long inter-comparison intervals produced a significant increase in the DL-IPD compared to the medium and long inter-comparison intervals condition without intervening tones. The result obtained in the condition with a short inter-comparison interval was roughly equivalent to that obtained for the medium inter-comparison interval without intervening tones. These results suggest that the ability to retain information about the location of a sound within AWM decays slowly; however, the presence of intervening sounds readily disrupts the retention process. Overall, the results suggest that the temporal decay of information within AWM regarding the location of a sound from a listener's environment is so gradual that it can be maintained in trace memory for tens of seconds in the absence of intervening acoustic signals. Conversely, the presence of intervening sounds within the retention interval may facilitate the use of context memory, even for shorter retention intervals, resulting in a less detailed, but relevant representation of the location that is resistant to further degradation. PMID:20547219

  9. Reversing the Signaled Magnitude Effect in Delayed Matching to Sample: Delay-Specific Remembering?

    ERIC Educational Resources Information Center

    White, K. Geoffrey; Brown, Glenn S.

    2011-01-01

    Pigeons performed a delayed matching-to-sample task in which large or small reinforcers for correct remembering were signaled during the retention interval. Accuracy was low when small reinforcers were signaled, and high when large reinforcers were signaled (the signaled magnitude effect). When the reinforcer-size cue was switched from small to…

  10. Finite-size effects on return interval distributions for weakest-link-scaling systems.

    PubMed

    Hristopulos, Dionissios T; Petrakis, Manolis P; Kaniadakis, Giorgio

    2014-05-01

    The Weibull distribution is a commonly used model for the strength of brittle materials and earthquake return intervals. Deviations from Weibull scaling, however, have been observed in earthquake return intervals and the fracture strength of quasibrittle materials. We investigate weakest-link scaling in finite-size systems and deviations of empirical return interval distributions from the Weibull distribution function. Our analysis employs the ansatz that the survival probability function of a system with complex interactions among its units can be expressed as the product of the survival probability functions for an ensemble of representative volume elements (RVEs). We show that if the system comprises a finite number of RVEs, it obeys the κ-Weibull distribution. The upper tail of the κ-Weibull distribution declines as a power law in contrast with Weibull scaling. The hazard rate function of the κ-Weibull distribution decreases linearly after a waiting time τ(c) ∝ n(1/m), where m is the Weibull modulus and n is the system size in terms of representative volume elements. We conduct statistical analysis of experimental data and simulations which show that the κ Weibull provides competitive fits to the return interval distributions of seismic data and of avalanches in a fiber bundle model. In conclusion, using theoretical and statistical analysis of real and simulated data, we demonstrate that the κ-Weibull distribution is a useful model for extreme-event return intervals in finite-size systems. PMID:25353774

  11. Effects of divided doses of a bronchodilator aerosol and the intervening time interval on the forced expiration.

    PubMed

    Hidinger, K G; Bake, B

    1986-01-01

    Twelve patients with bronchial asthma participated in a blind, randomized, crossover study comparing the effects of 500 micrograms terbutaline in one inhalation, 125 micrograms in four inhalations taken in rapid succession, and 125 micrograms in four inhalations taken with an intervening time interval of 30 min. There were no significant differences between the three modes of inhalation of 500 micrograms terbutaline in any of the spirometric variables, i.e., 1-second forced expiratory volume, forced vital capacity, and maximal airflows when 50 and 75% of the forced vital capacity was exhaled from the total lung capacity. However, there were neither any significant differences between the levels of bronchodilation reached after administration of 500 micrograms and 2 or 3 X 125 micrograms terbutaline with an intervening time interval of 30 min. The time interval between the divided doses was possibly too long to achieve maximum accumulated effect of the four divided doses.

  12. Priority effects of time of arrival of plant functional groups override sowing interval or density effects: a grassland experiment.

    PubMed

    von Gillhaussen, Philipp; Rascher, Uwe; Jablonowski, Nicolai D; Plückers, Christine; Beierkuhnlein, Carl; Temperton, Vicky M

    2014-01-01

    Priority effects occur when species that arrive first in a habitat significantly affect the establishment, growth, or reproduction of species arriving later and thus affect functioning of communities. However, we know little about how the timing of arrival of functionally different species may alter structure and function during assembly. Even less is known about how plant density might interact with initial assembly. In a greenhouse experiment legumes, grasses or forbs were sown a number of weeks before the other two plant functional types were sown (PFT) in combination with a sowing density treatment. Legumes, grasses or non-legume forbs were sown first at three different density levels followed by sowing of the remaining PFTs after three or six-weeks. We found that the order of arrival of different plant functional types had a much stronger influence on aboveground productivity than sowing density or interval between the sowing events. The sowing of legumes before the other PFTs produced the highest aboveground biomass. The larger sowing interval led to higher asymmetric competition, with highest dominance of the PFT sown first. It seems that legumes were better able to get a head-start and be productive before the later groups arrived, but that their traits allowed for better subsequent establishment of non-legume PFTs. Our study indicates that the manipulation of the order of arrival can create priority effects which favour functional groups of plants differently and thus induce different assembly routes and affect community composition and functioning.

  13. Priority effects of time of arrival of plant functional groups override sowing interval or density effects: a grassland experiment.

    PubMed

    von Gillhaussen, Philipp; Rascher, Uwe; Jablonowski, Nicolai D; Plückers, Christine; Beierkuhnlein, Carl; Temperton, Vicky M

    2014-01-01

    Priority effects occur when species that arrive first in a habitat significantly affect the establishment, growth, or reproduction of species arriving later and thus affect functioning of communities. However, we know little about how the timing of arrival of functionally different species may alter structure and function during assembly. Even less is known about how plant density might interact with initial assembly. In a greenhouse experiment legumes, grasses or forbs were sown a number of weeks before the other two plant functional types were sown (PFT) in combination with a sowing density treatment. Legumes, grasses or non-legume forbs were sown first at three different density levels followed by sowing of the remaining PFTs after three or six-weeks. We found that the order of arrival of different plant functional types had a much stronger influence on aboveground productivity than sowing density or interval between the sowing events. The sowing of legumes before the other PFTs produced the highest aboveground biomass. The larger sowing interval led to higher asymmetric competition, with highest dominance of the PFT sown first. It seems that legumes were better able to get a head-start and be productive before the later groups arrived, but that their traits allowed for better subsequent establishment of non-legume PFTs. Our study indicates that the manipulation of the order of arrival can create priority effects which favour functional groups of plants differently and thus induce different assembly routes and affect community composition and functioning. PMID:24497995

  14. Effect of sprint interval training on circulatory function during exercise in sedentary, overweight/obese women.

    PubMed

    Trilk, Jennifer L; Singhal, Arpit; Bigelman, Kevin A; Cureton, Kirk J

    2011-08-01

    Very high-intensity, low-volume, sprint interval training (SIT) increases muscle oxidative capacity and may increase maximal oxygen uptake ([Formula: see text]), but whether circulatory function is improved, and whether SIT is feasible in overweight/obese women is unknown. To examine the effects of SIT on [Formula: see text] and circulatory function in sedentary, overweight/obese women. Twenty-eight women with BMI > 25 were randomly assigned to SIT or control (CON) groups. One week before pre-testing, subjects were familarized to [Formula: see text] testing and the workload that elicited 50% [Formula: see text] was calculated. Pre- and post-intervention, circulatory function was measured at 50% of the pre-intervention [Formula: see text], and a GXT was performed to determine [Formula: see text]. During the intervention, SIT training was given for 3 days/week for 4 weeks. Training consisted of 4-7, 30-s sprints on a stationary cycle (5% body mass as resistance) with 4 min active recovery between sprints. CON maintained baseline physical activity. Post-intervention, heart rate (HR) was significantly lower and stroke volume (SV) significantly higher in SIT (-8.1 and 11.4%, respectively; P < 0.05) during cycling at 50% [Formula: see text]; changes in CON were not significant (3 and -4%, respectively). Changes in cardiac output ([Formula: see text]) and arteriovenous oxygen content difference [(a - v)O(2) diff] were not significantly different for SIT or CON. The increase in [Formula: see text] by SIT was significantly greater than by CON (12 vs. -1%). Changes by SIT and CON in HR(max) (-1 vs. -1%) were not significantly different. Four weeks of SIT improve circulatory function during submaximal exercise and increases [Formula: see text] in sedentary, overweight/obese women.

  15. The protective effects of continuous and interval exercise in athletes with exercise-induced asthma.

    PubMed

    McKenzie, D C; McLuckie, S L; Stirling, D R

    1994-08-01

    To determine the effect of two forms of warm-up on postexercise bronchoconstriction in athletes with exercise-induced asthma, 12 moderately trained persons with asthma (age = 26.5 +/- 2.2 yr; height = 169.2 +/- 2.6 cm; weight = 64.3 +/- 2.6kg; VO2max = 52.7 +/- 1.3 ml.kg-1.min-1) were tested under three experimental conditions; continuous warm-up (CW), interval warm-up (IW), and control (C). CW consisted of 15 min of treadmill running at a velocity corresponding to 60% VO2max followed by an exercise challenge test (ET = 6 min at 90% VO2max). IW involved 8 x 30-s runs (1.5 min rest between bouts of exercise), at an intensity equivalent to 100% VO2max, followed by an ET. C consisted of only the ET. FEV1, FVC, and MMEFR were measured prior to the experimental conditions, repeated before the ET, and every 2 min during a 25-min passive recovery period, using a Breon spirometer. Postexercise changes in pulmonary function were recorded as the largest decrese in FEV1, FVC, and MMEFR during the recovery period, and expressed as a percentage of baseline values. Significant differences were detected in %FEV1 (34. 6,16.7,29.7: P = 0.009), %FVC (30.0,10.7,21.0: P = 0.03), and %MMEFR (50.0,30.2,43.4: P = 0.05), in comparing C, CW, and IW, respectively. Scheffe's test detected significance (P < 0.05) between C and CW for all three dependent variables; no statistical significance between C and IW or IW and CW occurred. These data indicate that a continuous warm-up of 15 min at 60% VO2max can significantly decrease postexercise bronchoconstriction in moderately trained athletes.

  16. Effects of variable sequences of food availability on interval time-place learning by pigeons.

    PubMed

    García-Gallardo, Daniel; Carpio, Claudio

    2016-09-01

    The effects of within session variability of the sequences of food availability in a 16 period Time Place Learning (TPL) task on the performance of pigeons were assessed. Two groups of birds were exposed to two conditions. For group 1 (N=3), the first condition consisted of a TPL task in which food could be obtained according to a Random Interval (RI) 25s schedule of reinforcement in one of four feeders, the correct feeder changed every 3min. The same sequence was repeated four times within every training session (Fixed Sequence). The second condition was exactly the same as the first one with the exception that the sequence in which the correct feeder changed was randomized, yielding a total of four randomized sequences of food availability each session (Variable Sequence). An Open Hopper Test (OHT) was conducted at the end of each condition. Birds in group 2 (N=3) experienced the same conditions but in the reverse order. Results showed high percent correct responses for both group of birds under both conditions. However, birds were able to time the availability period's duration only under the Fixed Sequence condition, as shown by anticipation, anticipation of depletion and persistence of visiting patterns on the OHT. The implications of these results to Gallistels (1990) tripartite time-place-event memory code model are discussed, pointing out that these results are in line with previous findings about the important role that spatial parameters of a TPL task can play, for accurate timing was precluded when a variable sequence was employed. PMID:27425658

  17. Effective confidence interval estimation of fault-detection process of software reliability growth models

    NASA Astrophysics Data System (ADS)

    Fang, Chih-Chiang; Yeh, Chun-Wu

    2016-09-01

    The quantitative evaluation of software reliability growth model is frequently accompanied by its confidence interval of fault detection. It provides helpful information to software developers and testers when undertaking software development and software quality control. However, the explanation of the variance estimation of software fault detection is not transparent in previous studies, and it influences the deduction of confidence interval about the mean value function that the current study addresses. Software engineers in such a case cannot evaluate the potential hazard based on the stochasticity of mean value function, and this might reduce the practicability of the estimation. Hence, stochastic differential equations are utilised for confidence interval estimation of the software fault-detection process. The proposed model is estimated and validated using real data-sets to show its flexibility.

  18. Effect of interpregnancy interval on risk of spontaneous preterm birth in Emirati women, United Arab Emirates.

    PubMed Central

    Al-Jasmi, Fatima; Al-Mansoor, Fatima; Alsheiba, Aisha; Carter, Anne O.; Carter, Thomas P.; Hossain, M. Moshaddeque

    2002-01-01

    OBJECTIVE: To investigate whether a short interpregnancy interval is a risk factor for preterm birth in Emirati women, where there is a wide range of interpregnancy intervals and uniformity in potentially confounding factors. METHODS: A case-control design based on medical records was used. A case was defined as a healthy multiparous Emirati woman delivering a healthy singleton spontaneously before 37 weeks of gestation between 1997 and 2000, and a control was defined as the next eligible similar woman delivering after 37 weeks of gestation. Women were excluded if there was no information available about their most recent previous pregnancy or if it had resulted in a multiple or preterm birth. Data collected from charts and delivery room records were analysed using the STATA statistical package. All variables found to be valid, stable and significant by univariate analysis were included in multivariate logistic regression analysis. FINDINGS: There were 128 cases who met the eligibility criteria; 128 controls were selected. Short interpregnancy intervals were significantly associated with case status (P<0.05). The multivariate adjusted odds ratios for the 1st, 2nd, and 4th quartiles of interpregnancy interval compared with the lowest-risk 3rd quartile were 8.2, 5.4, and 2.0 (95% confidence intervals: 3.5-19.2, 2.4-12.6, and 0.9- 4.5 respectively). CONCLUSION: A short interpregnancy interval is a risk factor for spontaneous preterm birth in Emirati women. The magnitude of the risk and the risk gradient between exposure quartiles suggest that the risk factor is causal and that its modification would reduce the risk of preterm birth. PMID:12481208

  19. Effects of paradigm and inter-stimulus interval on age differences in eyeblink classical conditioning in rabbits.

    PubMed

    Woodruff-Pak, Diana S; Seta, Susan E; Roker, LaToya A; Lehr, Melissa A

    2007-04-01

    The aim of this study was to examine parameters affecting age differences in eyeblink classical conditioning in a large sample of young and middle-aged rabbits. A total of 122 rabbits of mean ages of 4 or 26 mo were tested at inter-stimulus intervals (ISIs) of 600 or 750 msec in the delay or trace paradigms. Paradigm affected both age groups dramatically, with superior performance in the delay paradigm. ISI was salient as middle-aged rabbits were significantly impaired in 750-msec compared with 600-msec delays, and young rabbits were significantly less impaired in 600-msec than in 750-msec trace. Young rabbits performed equally well at both delay ISIs, and consequently, there were significant age differences in 750-msec but not in 600-msec delays. Middle-aged rabbits performed poorly at both 600- and 750-msec trace, resulting in significant age differences in 600-msec but not in 750-msec trace. Timing of the conditioned response has been associated with cerebellar cortical function. Normal aging of the cerebellar cortex likely contributed to the magnitude of the effect of ISI in delay conditioning in middle-aged rabbits. Results demonstrate that the magnitude of age differences in eyeblink conditioning can be enlarged or eliminated by ISI and paradigm.

  20. Effects of paradigm and inter-stimulus interval on age differences in eyeblink classical conditioning in rabbits

    PubMed Central

    Woodruff-Pak, Diana S.; Seta, Susan E.; Roker, LaToya A.; Lehr, Melissa A.

    2007-01-01

    The aim of this study was to examine parameters affecting age differences in eyeblink classical conditioning in a large sample of young and middle-aged rabbits. A total of 122 rabbits of mean ages of 4 or 26 mo were tested at inter-stimulus intervals (ISIs) of 600 or 750 msec in the delay or trace paradigms. Paradigm affected both age groups dramatically, with superior performance in the delay paradigm. ISI was salient as middle-aged rabbits were significantly impaired in 750-msec compared with 600-msec delays, and young rabbits were significantly less impaired in 600-msec than in 750-msec trace. Young rabbits performed equally well at both delay ISIs, and consequently, there were significant age differences in 750-msec but not in 600-msec delays. Middle-aged rabbits performed poorly at both 600- and 750-msec trace, resulting in significant age differences in 600-msec but not in 750-msec trace. Timing of the conditioned response has been associated with cerebellar cortical function. Normal aging of the cerebellar cortex likely contributed to the magnitude of the effect of ISI in delay conditioning in middle-aged rabbits. Results demonstrate that the magnitude of age differences in eyeblink conditioning can be enlarged or eliminated by ISI and paradigm. PMID:17522017

  1. Confidence Intervals for Effect Sizes: Compliance and Clinical Significance in the "Journal of Consulting and Clinical Psychology"

    ERIC Educational Resources Information Center

    Odgaard, Eric C.; Fowler, Robert L.

    2010-01-01

    Objective: In 2005, the "Journal of Consulting and Clinical Psychology" ("JCCP") became the first American Psychological Association (APA) journal to require statistical measures of clinical significance, plus effect sizes (ESs) and associated confidence intervals (CIs), for primary outcomes (La Greca, 2005). As this represents the single largest…

  2. The Effect of Speech Rate on Stuttering Frequency, Phonated Intervals, Speech Effort, and Speech Naturalness during Chorus Reading

    ERIC Educational Resources Information Center

    Davidow, Jason H.; Ingham, Roger J.

    2013-01-01

    Purpose: This study examined the effect of speech rate on phonated intervals (PIs), in order to test whether a reduction in the frequency of short PIs is an important part of the fluency-inducing mechanism of chorus reading. The influence of speech rate on stuttering frequency, speaker-judged speech effort, and listener-judged naturalness was also…

  3. The Effects of Short Interval Delay of Reinforcement Upon Human Discrimination Learning. IMRID Papers and Reports Vol. 4 No. 12.

    ERIC Educational Resources Information Center

    Kral, Paul A.; And Others

    Investigates the effect of delay of reinforcement upon human discrimination learning with particular emphasis on the form of the gradient within the first few seconds of delay. In previous studies subjects are usually required to make an instrumental response to a stimulus, this is followed by the delay interval, and finally, the reinforcement…

  4. Category-boundary effects and speeded sorting with a harmonic musical-interval continuum: evidence for dual processing.

    PubMed

    Zatorre, R J

    1983-10-01

    In the first experiment, a continuum of 10 harmonic musical intervals was constructed from a minor to a major third. Four pairs of stimuli with constant physical distances were presented to seven musicians in a two-interval forced-choice discrimination task. Either silence, an interfering tone, or a noise burst was interposed between the two stimuli in a pair. Unbiased discriminability was found to be consistently higher for pairs straddling the boundary between two categories than for the endpoint pairs. The interfering tone lowered overall discrimination but left the shape of the function unchanged, whereas the noise burst had no effect. Experiment 2 used a similar paradigm, but the continuum consisted of the single tone that had cued the minor-major distinction for intervals. Discrimination of this series did not show consistent changes as a function of continuum position. In Experiment 3, triads that varied in either interval or overall pitch were presented to musicians for sorting according to one dimension or another. The result was that there were much longer latencies to sort according to interval when pitch varied irrelevantly than vice versa. These results demonstrate that there are changes in discriminability associated with learned categories and suggest that there may be two hierarchically organized stages. A dual-processing model is discussed in which the listener has available both auditory and categorical information.

  5. Effects of repetition, interval between treatments and season on the results from laparoscopic ovum pick-up in goats.

    PubMed

    Pierson, J; Wang, B; Neveu, N; Sneek, L; Côté, F; Karatzas, C N; Baldassarre, H

    2004-01-01

    The present study was conducted to evaluate the follicular response and oocyte yield following repeated gonadotrophin stimulation and laparoscopic aspiration in goats and to assess the effects of the time interval between procedures and season. A total of 98 adult goats were subjected to laparoscopic ovum pick-up (LOPU) five consecutive times in a transgenic production programme. Oestrus was synchronised by means of intravaginal sponges inserted for 10 days coupled with 125 microg cloprostenol 36 h before sponge removal and LOPU, and follicular development was stimulated with 80 mg follicle stimulating hormone and 300 IU equine chorionic gonadotrophin administered 36 h before LOPU. No difference was detected in the response for LOPUs 1, 2, 3 and 4. Although a small decrease in response was detected at LOPU 5 (P < 0.05), the numbers of follicles aspirated and oocytes recovered were not different from those at LOPU 1 and LOPUs 1 and 4, respectively. With respect to time interval between LOPU and season, all intervals and seasons produced acceptable responses, with no difference in follicles aspirated and oocytes recovered between intervals and seasons. These results indicate that LOPU may be repeated up to five times in goats at different intervals and in different seasons with little or no important change in overall response.

  6. Sequential Processing and the Matching-Stimulus Interval Effect in ERP Components: An Exploration of the Mechanism Using Multiple Regression

    PubMed Central

    Steiner, Genevieve Z.; Barry, Robert J.; Gonsalvez, Craig J.

    2016-01-01

    In oddball tasks, increasing the time between stimuli within a particular condition (target-to-target interval, TTI; nontarget-to-nontarget interval, NNI) systematically enhances N1, P2, and P300 event-related potential (ERP) component amplitudes. This study examined the mechanism underpinning these effects in ERP components recorded from 28 adults who completed a conventional three-tone oddball task. Bivariate correlations, partial correlations and multiple regression explored component changes due to preceding ERP component amplitudes and intervals found within the stimulus series, rather than constraining the task with experimentally constructed intervals, which has been adequately explored in prior studies. Multiple regression showed that for targets, N1 and TTI predicted N2, TTI predicted P3a and P3b, and Processing Negativity (PN), P3b, and TTI predicted reaction time. For rare nontargets, P1 predicted N1, NNI predicted N2, and N1 predicted Slow Wave (SW). Findings show that the mechanism is operating on separate stages of stimulus-processing, suggestive of either increased activation within a number of stimulus-specific pathways, or very long component generator recovery cycles. These results demonstrate the extent to which matching-stimulus intervals influence ERP component amplitudes and behavior in a three-tone oddball task, and should be taken into account when designing similar studies. PMID:27445774

  7. Effect of Empty Uterine Space on Placental Development, Farrowing Intervals, and Stillbirth

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Prolonged farrowing intervals (FI) are associated with stillbirth and decrease as litter size increases, but the reason is unclear. We hypothesized that unoccupied uterine space associated with small litters could present a barrier to delivery of piglets and increase FI. Empty uterine space was crea...

  8. The Effect of Different Musical Timbres on Students' Identification of Melodic Intervals.

    ERIC Educational Resources Information Center

    Hinton, Dallas E.

    For this study, five hypotheses were formulated stating that ability to identify melodic intervals during music dictation is not affected by (1) the differences in timbre, (2) the use of familiar or unfamiliar timbres (MAJOR), (3) formal ear training experience (FETE), or (4) playing/performing experience on an instrument (PPEM), and (5) that…

  9. The Effects of Variable-Interval Reinforcement on Academic Engagement: A Demonstration of Matching Theory.

    ERIC Educational Resources Information Center

    Martens, Brian K.; And Others

    1992-01-01

    Two experiments analyzed the single-alternative form of the matching law as a description of student behavior. Four students (ages 8-10) exhibiting off-task behavior were exposed to variable-interval schedules of social reinforcement contingent on academic engagement. Results provided evidence that subject behavior was under control of the…

  10. Effectiveness and Safety of High-Intensity Interval Training in Patients With Type 2 Diabetes

    PubMed Central

    Francois, Monique E.

    2015-01-01

    IN BRIEF Recent research has shown that high-intensity interval training (HIIT) can promote improvements in glucose control and cardiovascular health in individuals with type 2 diabetes. This article summarizes the evidence and highlights the ways in which HIIT might be safely implemented as an adjunct to more traditional exercise approaches. PMID:25717277

  11. On the Effective Construction of Compactly Supported Wavelets Satisfying Homogenous Boundary Conditions on the Interval

    NASA Technical Reports Server (NTRS)

    Chiavassa, G.; Liandrat, J.

    1996-01-01

    We construct compactly supported wavelet bases satisfying homogeneous boundary conditions on the interval (0,1). The maximum features of multiresolution analysis on the line are retained, including polynomial approximation and tree algorithms. The case of H(sub 0)(sup 1)(0, 1)is detailed, and numerical values, required for the implementation, are provided for the Neumann and Dirichlet boundary conditions.

  12. Confidence Intervals for an Effect Size Measure in Multiple Linear Regression

    ERIC Educational Resources Information Center

    Algina, James; Keselman, H. J.; Penfield, Randall D.

    2007-01-01

    The increase in the squared multiple correlation coefficient ([Delta]R[squared]) associated with a variable in a regression equation is a commonly used measure of importance in regression analysis. The coverage probability that an asymptotic and percentile bootstrap confidence interval includes [Delta][rho][squared] was investigated. As expected,…

  13. Classical Conditioning and Retention of the Infant's Eyelid Response: Effects of Age and Interstimulus Interval.

    ERIC Educational Resources Information Center

    Little, Arlene H.; And Others

    1984-01-01

    Reports that lengthy interstimulus interval facilitates classical conditioning in very young infants. Infants trained in a single session at 20 days of age exhibited reliable retention of the conditioned eyelid reflex 10 days later, but infants 10 days of age did not. (Author)

  14. Effect of denture cleansers on surface hardness of resilient denture liners at various time intervals- an in vitro study

    PubMed Central

    Pahuja, Rasleen Kaur; Bansal, Sanjay

    2013-01-01

    PURPOSE This study was aimed to determine the effect of two chemically distinct denture cleansers and water on the surface hardness of acrylic and silicone based soft denture liners at various time intervals. MATERIALS AND METHODS Two commonly used commercial resilient liner material were selected based on their chemical composition (silicone- and acrylic-based soft liners) for this investigation. 120 cylindrical specimens were made of 15 mm × 10 mm dimensions (according to ASTM: D-2240-64T) in a custom made metal mold. All specimens were stored in artificial saliva throughout the study. Forty specimens were cleansed daily in 0.5% sodium hypochlorite solution; forty were cleansed in sodium perborate and remaining forty specimens were daily rinsed in water. Testing was done at 1 week, 1 month, 3 months and 6 months for surface hardness using a Shore A Durometer. A mean of 3 reading for each sample was subjected to one-way ANOVA, Post Hoc test and pair-t test for statistical analysis. P values of less than 0.05 were taken as statistically significant. RESULTS Surface hardness of all the samples was significantly higher after a period of 6 months irrespective of the cleansing treatment. Minor changes were observed between control, sodium hypochlorite and sodium perborate groups with time. Greater change was observed in surface hardness of acrylic-based soft denture liners as compared to silicone-based soft liners for all groups, as time progressed. CONCLUSION Silicone-based soft denture liners performed significantly better in all cleansing treatments than acrylic-based soft denture liners. PMID:24049568

  15. Effects of sampling standardization on estimates of Phanerozoic marine diversification

    PubMed Central

    Alroy, J.; Marshall, C. R.; Bambach, R. K.; Bezusko, K.; Foote, M.; Fürsich, F. T.; Hansen, T. A.; Holland, S. M.; Ivany, L. C.; Jablonski, D.; Jacobs, D. K.; Jones, D. C.; Kosnik, M. A.; Lidgard, S.; Low, S.; Miller, A. I.; Novack-Gottshall, P. M.; Olszewski, T. D.; Patzkowsky, M. E.; Raup, D. M.; Roy, K.; Sepkoski, J. J.; Sommers, M. G.; Wagner, P. J.; Webber, A.

    2001-01-01

    Global diversity curves reflect more than just the number of taxa that have existed through time: they also mirror variation in the nature of the fossil record and the way the record is reported. These sampling effects are best quantified by assembling and analyzing large numbers of locality-specific biotic inventories. Here, we introduce a new database of this kind for the Phanerozoic fossil record of marine invertebrates. We apply four substantially distinct analytical methods that estimate taxonomic diversity by quantifying and correcting for variation through time in the number and nature of inventories. Variation introduced by the use of two dramatically different counting protocols also is explored. We present sampling-standardized diversity estimates for two long intervals that sum to 300 Myr (Middle Ordovician-Carboniferous; Late Jurassic-Paleogene). Our new curves differ considerably from traditional, synoptic curves. For example, some of them imply unexpectedly low late Cretaceous and early Tertiary diversity levels. However, such factors as the current emphasis in the database on North America and Europe still obscure our view of the global history of marine biodiversity. These limitations will be addressed as the database and methods are refined. PMID:11353852

  16. Effect of suckling restriction with nose plates and premature weaning on postpartum anestrous interval in primiparous cows under range conditions.

    PubMed

    Quintans, G; Vázquez, A I; Weigel, K A

    2009-11-01

    Suckling and nutrition are generally recognized as two major factors controlling the duration of the postpartum anovulatory period. In the present study, the effect of premature weaning and suckling restriction with nose plates (NPs) on cow and calf performance was evaluated. The study was conducted over 2 years; primiparous Hereford cows, weighing (mean+/-S.E.M.) 344+/-3.5kg and with 4.1+/-0.05 units of body condition score (BCS) (scale 1-8 [Vizcarra, J.A., Ibañez, W., Orcasberro, R., 1986. Repetibilidad y reproductibilidad de dos escalas para estimar la condición corporal de vacas Hereford. Investigaciones Agronómicas 7 (1), 45-47]) at calving, remained with their calves until 72.5+/-1.2 days postpartum (day 0). They were then assigned to one of three treatments: (i) calves with free access to their dams and ad libitum suckling (S, n=29); (ii) calves fitted with NPs for 14 days, but remained with their dams (NP, n=29), and (iii) calves that were weaned from their dams (W, n=28). All cows were anestrus at the time treatments commenced (day 0). All cows were blood sampled twice weekly from 1 week before the beginning of the experiment until the end of the mating period (day 74) for progesterone analysis. The mating period began on day 14. Cows in W treatment had ovulations earlier (P<0.05) than those in NP and S groups. Cows in the NP group had longer (P<0.05) intervals between the first progesterone increase and normal luteal phase than cows in the other two treatments groups (23.3+/-3.2 vs. 6.5+/-3.2 and 5.2+/-3.3 days for NP, S and W cows, respectively). Fifty per cent of the cows with NP had a short cycle (7 days) but there was a group of cows that had longer (P<0.05) intervals (66 days) between first progesterone increase and normal estrous activity. In the NP group, 8 of 29 cows had a short luteal phase and then a normal one; for 9 of these 29 cows progesterone concentrations remained low for 6 weeks from the beginning of the treatment; and for 12 of these

  17. Postmortem interval alters the water relaxation and diffusion properties of rat nervous tissue--implications for MRI studies of human autopsy samples.

    PubMed

    Shepherd, Timothy M; Flint, Jeremy J; Thelwall, Peter E; Stanisz, Greg J; Mareci, Thomas H; Yachnis, Anthony T; Blackband, Stephen J

    2009-02-01

    High-resolution imaging of human autopsy tissues may improve our understanding of in vivo MRI findings, but interpretation is complicated because samples are obtained by immersion fixation following a postmortem interval (PMI). This study tested the hypotheses that immersion fixation and PMI's from 0-24 h would alter the water relaxation and diffusion properties in rat cortical slice and spinal cord models of human nervous tissue. Diffusion data collected from rat cortical slices at multiple diffusion times (10-60 ms) and b-values (7-15,000 s/mm(2)) were analyzed using a two-compartment model with exchange. Rat spinal cords were characterized with standard diffusion tensor imaging (21 directions, b=1250 s/mm(2)). Switching from perfusion- to immersion-fixation at 0 h PMI altered most MRI properties of rat cortical slices and spinal cords, including a 22% decrease in fractional anisotropy (P<0.001). After 4 h PMI, cortical slice T(1) and T(2) increased 22% and 65% respectively (P<0.001), transmembrane water exchange decreased 23% (P<0.001) and intracellular proton fraction increased 25% (P=0.002). After 6 h PMI, spinal cord white matter fractional anisotropy had decreased 38% (P<0.001). MRI property changes were observed for PMIs up to 24 h. The MRI changes correlated with protease activity and histopathological signs of autolysis. Thus, immersion fixation and/or even short PMIs (4-6 h) altered the MRI properties of rat nervous tissue. This suggests comparisons between in vivo clinical MRI and MRI data from human autopsy tissues should be interpreted with caution. PMID:18996206

  18. Odor-context effects in free recall after a short retention interval: a new methodology for controlling adaptation.

    PubMed

    Isarida, Takeo; Sakai, Tetsuya; Kubota, Takayuki; Koga, Miho; Katayama, Yu; Isarida, Toshiko K

    2014-04-01

    The present study investigated context effects of incidental odors in free recall after a short retention interval (5 min). With a short retention interval, the results are not confounded by extraneous odors or encounters with the experimental odor and possible rehearsal during a long retention interval. A short study time condition (4 s per item), predicted not to be affected by adaptation to the odor, and a long study time condition (8 s per item) were used. Additionally, we introduced a new method for recovery from adaptation, where a dissimilar odor was briefly presented at the beginning of the retention interval, and we demonstrated the effectiveness of this technique. An incidental learning paradigm was used to prevent overshadowing from confounding the results. In three experiments, undergraduates (N = 200) incidentally studied words presented one-by-one and received a free recall test. Two pairs of odors and a third odor having different semantic-differential characteristics were selected from 14 familiar odors. One of the odors was presented during encoding, and during the test, the same odor (same-context condition) or the other odor within the pair (different-context condition) was presented. Without using a recovery-from-adaptation method, a significant odor-context effect appeared in the 4-s/item condition, but not in the 8-s/item condition. Using the recovery-from-adaptation method, context effects were found for both the 8- and the 4-s/item conditions. The size of the recovered odor-context effect did not change with study time. There were no serial position effects. Implications of the present findings are discussed.

  19. Effects of different intrastimulus interval on learning of the Konorski short-term memory test in dogs.

    PubMed

    Stasiak, M; Lawicka, W

    1991-01-01

    A differentiation of instrumental responses to auditory location stimuli using the Konorski Test was investigated. Each stimulus consisted of two components separated by intrastimulus interval. The components were click series presented from four loudspeakers situated in front of the animal, on horizontal and vertical axes. Each correct response, performed to the second component of positive stimulus, was rewarded by food. Responses to negative stimuli were not reinforced. Solving the test was possible by comparing the memory trace of the first component location, with location of actually presented second component. Two groups of dogs were trained. In one group positive and negative stimuli were presented, in which intrastimulus interval lasted 1 s. In the other group, differentiation training included stimuli with intrastimulus interval lasting 3 s. Unexpectedly, the first group was unable to reach differentiation criterion, whereas the second group reached criterion without difficulty. The effect of reaching the criterion with longer and not shorter interval between stimulus components, may be specifically related to location cues as opposed to reported earlier auditory quality stimuli.

  20. The effects of apremilast on the QTc interval in healthy male volunteers: a formal, thorough QT study

    PubMed Central

    Palmisano, Maria; Wu, Anfan; Assaf, Mahmoud; Liu, Liangang; Park, C. Hyung; Savant, Ishani; Liu, Yong; Zhou, Simon

    2016-01-01

    Objective: This study was conducted to evaluate the effect of apremilast and its major metabolites on the placebo-corrected change-from-baseline QTc interval of an electrocardiogram (ECG). Materials and methods: Healthy male subjects received each of 4 treatments in a randomized, crossover manner. In the 2 active treatment periods, apremilast 30 mg (therapeutic exposure) or 50 mg (supratherapeutic exposure) was administered twice daily for 9 doses. A placebo control was used to ensure double-blind treatment of apremilast, and an open-label, single dose of moxifloxacin 400 mg was administered as a positive control. ECGs were measured using 24-hour digital Holter monitoring. Results: The two-sided 98% confidence intervals (CIs) for ΔΔQTcI of moxifloxacin completely exceeded 5 ms 2 – 4 hours postdose. For both apremilast dose studies, the least-squares mean ΔΔQTcI was < 1 ms at all time points, and the upper limit of two-sided 90% CIs was < 10 ms. There were no QT/QTc values > 480 ms or a change from baseline > 60 ms. Exploratory evaluation of pharmacokinetic/pharmacodynamic data showed no trend between the changes in QT/QTc interval and the concentration of apremilast or its major metabolites M12 and M14. Conclusions: Apremilast did not prolong the QT interval and appears to be safe and well tolerated up to doses of 50 mg twice daily. PMID:27285466

  1. Effects of High Intensity Interval Training on Pregnant Rats, and the Placenta, Heart and Liver of Their Fetuses

    PubMed Central

    Hafstad, Anne Dragøy; Basnet, Purusotam; Ytrehus, Kirsti; Acharya, Ganesh

    2015-01-01

    Objective To investigate the effects of high intensity interval training (HIIT) on the maternal heart, fetuses and placentas of pregnant rats. Methods Female Sprague-Dawley rats were randomly assigned to HIIT or sedentary control groups. The HIIT group was trained for 6 weeks with 10 bouts of high intensity uphill running on a treadmill for four minutes (at 85–90% of maximal oxygen consumption) for five days/week. After three weeks of HIIT, rats were mated. After six weeks (gestational day 20 in pregnant rats), echocardiography was performed to evaluate maternal cardiac function. Real-time PCR was performed for the quantification of gene expression, and oxidative stress and total antioxidant capacity was assessed in the tissue samples. Results Maternal heart weight and systolic function were not affected by HIIT or pregnancy. In the maternal heart, expression of 11 of 22 genes related to cardiac remodeling was influenced by pregnancy but none by HIIT. Litter size, fetal weight and placental weight were not affected by HIIT. Total antioxidant capacity, malondialdehyde content, peroxidase and superoxide dismutase activity measured in the placenta, fetal heart and liver were not influenced by HIIT. HIIT reduced the expression of eNOS (p = 0.03), hypoxia-inducible factor 1α (p = 0.04) and glutathione peroxidase 4.2 (p = 0.02) in the fetal liver and increased the expression of vascular endothelial growth factor-β (p = 0.014), superoxide dismutase 1 (p = 0.001) and tissue inhibitor of metallopeptidase 3 (p = 0.049) in the fetal heart. Conclusions Maternal cardiac function and gene expression was not affected by HIIT. Although HIIT did not affect fetal growth, level of oxidative stress and total antioxidant capacity in the fetal tissues, some genes related to oxidative stress were altered in the fetal heart and liver indicating that protective mechanisms may be activated. PMID:26566220

  2. Radiation-induced taste aversion: effects of radiation exposure level and the exposure-taste interval

    SciTech Connect

    Spector, A.C.; Smith, J.C.; Hollander, G.R.

    1986-05-01

    Radiation-induced taste aversion has been suggested to possibly play a role in the dietary difficulties observed in some radiotherapy patients. In rats, these aversions can still be formed even when the radiation exposure precedes the taste experience by several hours. This study was conducted to examine whether increasing the radiation exposure level could extend the range of the exposure-taste interval that would still support the formation of a taste aversion. Separate groups of rats received either a 100 or 300 R gamma-ray exposure followed 1, 3, 6, or 24 h later by a 10-min saccharin (0.1% w/v) presentation. A control group received a sham exposure followed 1 h later by a 10-min saccharin presentation. Twenty-four hours following the saccharin presentation all rats received a series of twelve 23-h two-bottle preference tests between saccharin and water. The results indicated that the duration of the exposure-taste interval plays an increasingly more important role in determining the initial extent of the aversion as the dose decreases. The course of recovery from taste aversion seems more affected by dose than by the temporal parameters of the conditioning trial.

  3. Effect of creatine supplementation during the last week of gestation on birth intervals, stillbirth, and preweaning mortality in pigs.

    PubMed

    Vallet, J L; Miles, J R; Rempel, L A

    2013-05-01

    We hypothesized that creatine supplementation would reduce birth intervals, stillbirth rate, and preweaning survival in pigs because of its reported improvement of athletic performance in humans. In Exp. 1, gilts (n = 42) and first parity sows (n = 75) were mated at estrus. Beginning on d 110 of gestation, dams received either no treatment or 20 g creatine daily until farrowing. At farrowing in November 2008, pigs were monitored by video camera to determine individual piglet birth intervals. On d 1, piglets were weighed, euthanized, and the cerebellum, brain stem, and spinal cord were collected from the largest and smallest piglets in each litter to measure myelin basic proteins, myelin cholesterol, glucocerebrosides, phosphatidylethanolamine, phosphatidylcholine, and sphingomyelin. Preweaning mortality of the remaining piglets was recorded, including whether a piglet had been overlayed by the dam. A second experiment was performed using gilts (n = 90), farrowing in July 2010, to test differential effects of creatine supplementation during hot, humid weather when dams typically have more difficulty farrowing. Once again, gilts were provided either no supplementation or 20 g creatine daily from d 110 to the day of farrowing. Gilts were video recorded during farrowing, piglets were weighed on d 1, and preweaning mortality (including overlays) was recorded. In Exp. 1, creatine supplementation had no effect on birth intervals or stillbirth rate. Creatine supplementation improved the amount of myelin lipids in brain regions of piglets, particularly the brain stem. Creatine supplementation also reduced overlays of low birth weight piglets from gilts but not second parity sows. Data from Exp. 2 were combined with gilt data from Exp. 1 to examine the effect of creatine, season, and their interaction. There were no effects of treatment or season on birth intervals, stillbirth rates, or overall preweaning mortality. Creatine treatment reduced the incidence of overlays in low

  4. Effect of collection-maturation interval time and pregnancy status of donor mares on oocyte developmental competence in horse cloning.

    PubMed

    Gambini, A; Andrés, G; Jarazo, J; Javier, J; Karlanian, F; Florencia, K; De Stéfano, A; Salamone, D F

    2014-02-01

    The current limitations for obtaining ovaries from slaughterhouses and the low efficiency of in vivo follicular aspiration necessitate a complete understanding of the variables that affect oocyte developmental competence in the equine. For this reason, we assessed the effect on equine oocyte meiotic competence and the subsequent in vitro cloned embryo development of 1) the time interval between ovary collection and the onset of oocyte in vitro maturation (collection-maturation interval time) and 2) the pregnancy status of the donor mares. To define the collection-maturation interval time, collected oocytes were classified according to the slaughtering time and the pregnancy status of the mare. Maturation rate was recorded and some matured oocytes of each group were used to reconstruct zona free cloned embryos. Nuclear maturation rates were lower when the collection-maturation interval time exceeded 10 h as compared to 4 h (32/83 vs. 76/136, respectively; P = 0.0128) and when the donor mare was pregnant as compared to nonpregnant (53/146 vs. 177/329, respectively; P = 0.0004). Low rates of cleaved embryos were observed when the collection-maturation interval time exceeded 10 h as compared to 6 to 10 h (11/27 vs. 33/44, respectively; P = 0.0056), but the pregnancy status of donor mares did not affect cloned equine blastocyst development (3/49 vs. 1/27 for blastocyst rates of nonpregnant and pregnant groups, respectively; P = 1.00). These results indicate that, to apply assisted reproductive technologies in horses, oocytes should be harvested within approximately 10 h after ovary collection. Also, even though ovaries from pregnant mares are a potential source of oocytes, they should be processed at the end of the collection routine due to the lower collection and maturation rate in this group.

  5. Effects of continuous vs interval exercise training on oxygen uptake efficiency slope in patients with coronary artery disease.

    PubMed

    Prado, D M L; Rocco, E A; Silva, A G; Rocco, D F; Pacheco, M T; Silva, P F; Furlan, V

    2016-02-01

    The oxygen uptake efficiency slope (OUES) is a submaximal index incorporating cardiovascular, peripheral, and pulmonary factors that determine the ventilatory response to exercise. The purpose of this study was to evaluate the effects of continuous exercise training and interval exercise training on the OUES in patients with coronary artery disease. Thirty-five patients (59.3±1.8 years old; 28 men, 7 women) with coronary artery disease were randomly divided into two groups: continuous exercise training (n=18) and interval exercise training (n=17). All patients performed graded exercise tests with respiratory gas analysis before and 3 months after the exercise-training program to determine ventilatory anaerobic threshold (VAT), respiratory compensation point, and peak oxygen consumption (peak VO2). The OUES was assessed based on data from the second minute of exercise until exhaustion by calculating the slope of the linear relation between oxygen uptake and the logarithm of total ventilation. After the interventions, both groups showed increased aerobic fitness (P<0.05). In addition, both the continuous exercise and interval exercise training groups demonstrated an increase in OUES (P<0.05). Significant associations were observed in both groups: 1) continuous exercise training (OUES and peak VO2 r=0.57; OUES and VO2 VAT r=0.57); 2) interval exercise training (OUES and peak VO2 r=0.80; OUES and VO2 VAT r=0.67). Continuous and interval exercise training resulted in a similar increase in OUES among patients with coronary artery disease. These findings suggest that improvements in OUES among CAD patients after aerobic exercise training may be dependent on peripheral and central mechanisms. PMID:26871969

  6. Effects of continuous vs interval exercise training on oxygen uptake efficiency slope in patients with coronary artery disease

    PubMed Central

    Prado, D.M.L.; Rocco, E.A.; Silva, A.G.; Rocco, D.F.; Pacheco, M.T.; Silva, P.F.; Furlan, V.

    2016-01-01

    The oxygen uptake efficiency slope (OUES) is a submaximal index incorporating cardiovascular, peripheral, and pulmonary factors that determine the ventilatory response to exercise. The purpose of this study was to evaluate the effects of continuous exercise training and interval exercise training on the OUES in patients with coronary artery disease. Thirty-five patients (59.3±1.8 years old; 28 men, 7 women) with coronary artery disease were randomly divided into two groups: continuous exercise training (n=18) and interval exercise training (n=17). All patients performed graded exercise tests with respiratory gas analysis before and 3 months after the exercise-training program to determine ventilatory anaerobic threshold (VAT), respiratory compensation point, and peak oxygen consumption (peak VO2). The OUES was assessed based on data from the second minute of exercise until exhaustion by calculating the slope of the linear relation between oxygen uptake and the logarithm of total ventilation. After the interventions, both groups showed increased aerobic fitness (P<0.05). In addition, both the continuous exercise and interval exercise training groups demonstrated an increase in OUES (P<0.05). Significant associations were observed in both groups: 1) continuous exercise training (OUES and peak VO2 r=0.57; OUES and VO2 VAT r=0.57); 2) interval exercise training (OUES and peak VO2 r=0.80; OUES and VO2 VAT r=0.67). Continuous and interval exercise training resulted in a similar increase in OUES among patients with coronary artery disease. These findings suggest that improvements in OUES among CAD patients after aerobic exercise training may be dependent on peripheral and central mechanisms. PMID:26871969

  7. Effects of continuous vs interval exercise training on oxygen uptake efficiency slope in patients with coronary artery disease.

    PubMed

    Prado, D M L; Rocco, E A; Silva, A G; Rocco, D F; Pacheco, M T; Silva, P F; Furlan, V

    2016-02-01

    The oxygen uptake efficiency slope (OUES) is a submaximal index incorporating cardiovascular, peripheral, and pulmonary factors that determine the ventilatory response to exercise. The purpose of this study was to evaluate the effects of continuous exercise training and interval exercise training on the OUES in patients with coronary artery disease. Thirty-five patients (59.3±1.8 years old; 28 men, 7 women) with coronary artery disease were randomly divided into two groups: continuous exercise training (n=18) and interval exercise training (n=17). All patients performed graded exercise tests with respiratory gas analysis before and 3 months after the exercise-training program to determine ventilatory anaerobic threshold (VAT), respiratory compensation point, and peak oxygen consumption (peak VO2). The OUES was assessed based on data from the second minute of exercise until exhaustion by calculating the slope of the linear relation between oxygen uptake and the logarithm of total ventilation. After the interventions, both groups showed increased aerobic fitness (P<0.05). In addition, both the continuous exercise and interval exercise training groups demonstrated an increase in OUES (P<0.05). Significant associations were observed in both groups: 1) continuous exercise training (OUES and peak VO2 r=0.57; OUES and VO2 VAT r=0.57); 2) interval exercise training (OUES and peak VO2 r=0.80; OUES and VO2 VAT r=0.67). Continuous and interval exercise training resulted in a similar increase in OUES among patients with coronary artery disease. These findings suggest that improvements in OUES among CAD patients after aerobic exercise training may be dependent on peripheral and central mechanisms.

  8. Interval arithmetic operations for uncertainty analysis with correlated interval variables

    NASA Astrophysics Data System (ADS)

    Jiang, Chao; Fu, Chun-Ming; Ni, Bing-Yu; Han, Xu

    2016-08-01

    A new interval arithmetic method is proposed to solve interval functions with correlated intervals through which the overestimation problem existing in interval analysis could be significantly alleviated. The correlation between interval parameters is defined by the multidimensional parallelepiped model which is convenient to describe the correlative and independent interval variables in a unified framework. The original interval variables with correlation are transformed into the standard space without correlation, and then the relationship between the original variables and the standard interval variables is obtained. The expressions of four basic interval arithmetic operations, namely addition, subtraction, multiplication, and division, are given in the standard space. Finally, several numerical examples and a two-step bar are used to demonstrate the effectiveness of the proposed method.

  9. The effect of acidosis on the interval-force relation and mechanical restitution in ferret papillary muscle.

    PubMed

    McCall, E; Orchard, C H

    1991-01-01

    1. The effect of a respiratory acidosis on the interval-force relation and on mechanical restitution was investigated in ferret papillary muscles. 2. Acidosis (pH 6.85) decreased developed force over a range of stimulation frequencies (1.0.06 Hz); the percentage decrease was greatest at the lowest stimulation frequencies. Qualitatively similar effects of acidosis on developed force were observed in the presence of the sarcoplasmic reticulum (SR) inhibitor ryanodine. 3. Mechanical restitution curves were constructed by interpolating extra-systoles at different test intervals following a train of steady-state beats. Mechanical restitution in ferret papillary muscle was triphasic: an initial, rapid, exponential increase in force with test intervals to 2 s, a further increase with test intervals between 60 and 90 s and then a slow decline, with a plateau at about 30 min (0.33 Hz, 30 degrees C). 4. Acidosis slowed the initial phase of mechanical restitution. The degree of slowing depended on the steady-state stimulation frequency, being greatest at low frequencies. 5. Inhibition of the SR abolished the initial phase of mechanical restitution, suggesting that this phase depends on Ca2+ release from the SR. 6. The strength of the first contraction after the extra-systole varied inversely with the size of the extra-systole under all conditions studied. 7. It is concluded that acidosis may inhibit the SR by altering the time required for Ca2+ recycling between contractions. This effect may alter Ca2+ release from the SR during acidosis, and may underlie the mechanical alternans (the alternation of small and large contractions) that can occur during acidosis.

  10. The effects of variable-interval reinforcement on academic engagement: a demonstration of matching theory.

    PubMed

    Martens, B K; Lochner, D G; Kelly, S Q

    1992-01-01

    The single-alternative form of the matching law has enjoyed extensive support in laboratory research with both animals and humans. However, few data exist concerning its validity as a description of behavior in applied settings. In Experiment 1, 2 fourth-grade students were exposed to variable-interval schedules of social reinforcement contingent on academic engagement. The data for each subject were then plotted via Herrnstein's equation. The results showed Herrnstein's equation to account for 99.1% and 87.6% of the variance in student engagement, respectively. In Experiment 2, control over student engagement by two of the reinforcement schedules was examined further within an alternating treatments design with similar results. The implications of these findings for linking experimental and applied behavior analysis are discussed.

  11. Low volume-high intensity interval exercise elicits antioxidant and anti-inflammatory effects in humans.

    PubMed

    Wadley, Alex J; Chen, Yu-Wen; Lip, Gregory Y H; Fisher, James P; Aldred, Sarah

    2016-01-01

    The purpose of the present study was to compare acute changes in oxidative stress and inflammation in response to steady state and low volume, high intensity interval exercise (LV-HIIE). Untrained healthy males (n = 10, mean ± s: age 22 ± 3 years; VO2MAX 42.7 ± 5.0 ml · kg(-1) · min(-1)) undertook three exercise bouts: a bout of LV-HIIE (10 × 1 min 90% VO2MAX intervals) and two energy-matched steady-state cycling bouts at a moderate (60% VO2MAX; 27 min, MOD) and high (80% VO2MAX; 20 min, HIGH) intensity on separate days. Markers of oxidative stress, inflammation and physiological stress were assessed before, at the end of exercise and 30 min post-exercise (post+30). At the end of all exercise bouts, significant changes in lipid hydroperoxides (LOOH) and protein carbonyls (PCs) (LOOH (nM): MOD +0.36; HIGH +3.09; LV-HIIE +5.51 and PC (nmol · mg(-1) protein): MOD -0.24; HIGH -0.11; LV-HIIE -0.37) were observed. Total antioxidant capacity (TAC) increased post+30, relative to the end of all exercise bouts (TAC (µM): MOD +189; HIGH +135; LV-HIIE +102). Interleukin (IL)-6 and IL-10 increased post+30 in HIGH and LV-HIIE only (P < 0.05). HIGH caused the greatest lymphocytosis, adrenaline and cardiovascular response (P < 0.05). At a reduced energy cost and physiological stress, LV-HIIE elicited similar cytokine and oxidative stress responses to HIGH.

  12. [Effects of variable-interval punishment on lever pressing maintained by variable-ratio reinforcement in the rat].

    PubMed

    Iida, Naritoshi; Kimura, Hiroshi

    2007-12-01

    The effects of reinforcement and punishment on response suppression under variable-ratio reinforcement and variable-interval punishment schedules were investigated. In the baseline period, lever pressing in rats was maintained by a variable-ratio food reinforcement schedule. In the punishment condition, responding was punished by a grid shock under a variable-interval schedule. Baseline and punishment conditions alternated, and were continued until the response stabilized. Three rats were given five or six punishment rates with a fixed reinforcement rate and another three rats were given four or five reinforcement rates with a fixed punishment rate. The results indicated that the responses were either completely suppressed or not suppressed at all. When the punishment rate increased or the reinforcement rate decreased, the response was suppressed completely. Whereas when the punishment rate decreased or the reinforcement rate increased, the responses were not suppressed. These results agree with the predictions of the molar theory.

  13. Radioactive sample effects on EDXRF spectra

    SciTech Connect

    Worley, Christopher G

    2008-01-01

    Energy dispersive X-ray fluorescence (EDXRF) is a rapid, straightforward method to determine sample elemental composition. A spectrum can be collected in a few minutes or less, and elemental content can be determined easily if there is adequate energy resolution. Radioactive alpha emitters, however, emit X-rays during the alpha decay process that complicate spectral interpretation. This is particularly noticeable when using a portable instrument where the detector is located in close proximity to the instrument analysis window held against the sample. A portable EDXRF instrument was used to collect spectra from specimens containing plutonium-239 (a moderate alpha emitter) and americium-241 (a heavy alpha emitter). These specimens were then analyzed with a wavelength dispersive XRF (WDXRF) instrument to demonstrate the differences to which sample radiation-induced X-ray emission affects the detectors on these two types of XRF instruments.

  14. Confidence Intervals, Power Calculation, and Sample Size Estimation for the Squared Multiple Correlation Coefficient under the Fixed and Random Regression Models: A Computer Program and Useful Standard Tables.

    ERIC Educational Resources Information Center

    Mendoza, Jorge L.; Stafford, Karen L.

    2001-01-01

    Introduces a computer package written for Mathematica, the purpose of which is to perform a number of difficult iterative functions with respect to the squared multiple correlation coefficient under the fixed and random models. These functions include computation of the confidence interval upper and lower bounds, power calculation, calculation of…

  15. Effects of inter-food interval on the variety effect in an instrumental food-seeking task. Clarifying the role of habituation.

    PubMed

    Thrailkill, Eric A; Epstein, Leonard H; Bouton, Mark E

    2015-01-01

    Food variety increases consumption and the rate of instrumental behavior that is reinforced by food in humans and animals. The present experiment investigated the relationship between the variety effect and habituation to food by testing the role of the interval between successive food presentations on responding in an operant food-seeking task. Habituation to food was expected at short, but not long, interfood intervals. The effects of variety on food's long-term reinforcing value were also tested. Four groups of rats were trained to lever-press on different random-interval (RI) schedules of reinforcement to earn 45-mg food pellets. Half the rats in each group received an unpredictable mix of grain and sucrose pellets, while the other half consistently received sucrose pellets. Response rate began at a high rate and then decreased within each 30-min session for groups that received short inter-pellet intervals (i.e., RI-3 s and RI-6 s reinforcement schedules) but not in groups that received longer inter-pellet intervals (i.e., RI-12 s and RI-24 s). A variety effect in the form of higher responding in the mix group than the sucrose-only group was also only evident at the shorter intervals. Habituation and variety effects were also most evident with the short intervals when we controlled for the number of reinforcers earned, suggesting that they were not merely due to rapid satiation. The variety effect also appeared quickly when groups trained with longer inter-pellet intervals (RI-12 s and RI-24 s) were transitioned to shorter intervals (RI-3 s and RI-6 s). There was no effect of variety on resistance to extinction or on resistance to the response-suppressing effects of pre-session feeding. The results more clearly link this version of the variety effect to the short-term effect of variety on food habituation.

  16. Effect of sample size in the evaluation of "in-field" sampling plans for aflatoxin B(1) determination in corn.

    PubMed

    Brera, Carlo; De Santis, Barbara; Prantera, Elisabetta; Debegnach, Francesca; Pannunzi, Elena; Fasano, Floriana; Berdini, Clara; Slate, Andrew B; Miraglia, Marina; Whitaker, Thomas B

    2010-08-11

    Use of proper sampling methods throughout the agri-food chain is crucial when it comes to effectively detecting contaminants in foods and feeds. The objective of the study was to estimate the performance of sampling plan designs to determine aflatoxin B(1) (AFB(1)) contamination in corn fields. A total of 840 ears were selected from a corn field suspected of being contaminated with aflatoxin. The mean and variance among the aflatoxin values for each ear were 10.6 mug/kg and 2233.3, respectively. The variability and confidence intervals associated with sample means of a given size could be predicted using an equation associated with the normal distribution. Sample sizes of 248 and 674 ears would be required to estimate the true field concentration of 10.6 mug/kg within +/-50 and +/-30%, respectively. Using the distribution information from the study, operating characteristic curves were developed to show the performance of various sampling plan designs. PMID:20608734

  17. Effects of oral cyclosporine on canine T-cell expression of IL-2 and IFN-gamma across a 12-h dosing interval

    PubMed Central

    FELLMAN, C. L.; ARCHER, T. M.; STOKES, J. V.; WILLS, R. W.; LUNSFORD, K. V.; MACKIN, A. J.

    2016-01-01

    The duration of immunosuppressive effects following oral cyclosporine in dogs is unknown. This study used flow cytometry and quantitative reverse transcription–polymerase chain reaction (qRT-PCR) to evaluate the effects of high-dose oral cyclosporine across a 12-h dosing interval. Expression of interleukin-2 (IL-2) and interferon-gamma (IFN-γ) was compared before and after 8 days of cyclosporine at 10 mg/kg every 12 h in six healthy dogs. Samples were collected at 0, 2, 4, and 8 h postdosing for analysis of unactivated and activated T-cell and whole blood cytokine expression using flow cytometry and qRT-PCR, respectively, and at 0, 2, 4, 6, 8, and 10 h postdosing for measurement of cyclosporine concentrations. Flow cytometry and qRT-PCR both demonstrated significant marked reductions in IL-2 and IFN-γ levels at 0, 2, 4, and 8 h after dosing compared to pretreatment levels (P < 0.05) for activated samples, with less consistent effects observed for unactivated samples. Both flow cytometry and qRT-PCR are viable techniques for measuring cyclosporine pharmacodynamics in dogs, yielding comparable results with activated samples. Two hours postdrug administration is the preferred time for concurrent assessment of peak drug concentration and cytokine expression, and T-cell activation is needed for optimal results. PMID:26676223

  18. A Study of Realistic Sampling-Variability Effects on Precipitation Measurements

    NASA Astrophysics Data System (ADS)

    O'Dell, K.; Larsen, M.

    2015-12-01

    Previous studies have investigated the effects of sampling variability on precipitation measurements using analytically driven simulation models. To explore the effects with more realism, data-derived distribution functions were used to develop a drop­-by-drop rain event simulation. Data based probability distributions for the number of raindrop arrivals in each sample and the event averaged drop size distribution were found using measurements of several precipitation events recorded by a two dimensional video disdrometer. Using these probability distribution functions, Monte-Carlo simulated rain events were developed and explored. The simulated events were sampled at intervals of several different durations associated with different average numbers of raindrops in each sample. The simulations reveal new insights to exploring the sample-size dependent convergence and distribution of bulk rainfall quantities (e.g. Z, R, Dm) as compared to the intrinsic ensemble values.

  19. Effect of the time interval between fusion and activation on epigenetic reprogramming and development of bovine somatic cell nuclear transfer embryos.

    PubMed

    Liu, Jun; Wang, Yongsheng; Su, Jianmin; Wang, Lijun; Li, Ruizhe; Li, Qian; Wu, Yongyan; Hua, Song; Quan, Fusheng; Guo, Zekun; Zhang, Yong

    2013-04-01

    Previous studies have shown that the time interval between fusion and activation (FA interval) play an important role in nuclear remodeling and in vitro development of somatic cell nuclear transfer (SCNT) embryos. However, the effects of FA interval on the epigenetic reprogramming and in vivo developmental competence of SCNT embryos remain unknown. In the present study, the effects of different FA intervals (0 h, 2 h, and 4 h) on the epigenetic reprogramming and developmental competence of bovine SCNT embryos were assessed. The results demonstrated that H3 lysine 9 (H3K9ac) levels decreased rapidly after fusion in all three groups. H3K9ac was practically undetectable 2 h after fusion in the 2-h and 4-h FA interval groups. However, H3K9ac was still evidently detectable in the 0-h FA interval group. The H3K9ac levels increased 10 h after fusion in all three groups, but were higher in the 2-h and 4-h FA interval groups than that in the 0-h FA interval group. The methylation levels of the satellite I region in day-7 blastocysts derived from the 2-h or 4-h FA interval groups was similar to that of in vitro fertilization blastocysts and is significantly lower than that of the 0-h FA interval group. SCNT embryos derived from 2-h FA interval group showed higher developmental competence than those from the 0-h and 4-h FA interval groups in terms of cleavage rate, blastocyst formation rate, apoptosis index, and pregnancy and calving rates. Hence, the FA interval is an important factor influencing the epigenetic reprogramming and developmental competence of bovine SCNT embryos.

  20. The combined effect of green tea and acute interval sprinting exercise on fat oxidation of trained and untrained males

    PubMed Central

    Gahreman, Daniel E; Boutcher, Yati N; Bustamante, Sonia; Boutcher, Stephen H

    2016-01-01

    [Purpose] This study investigated the combined effect of green tea and acute interval sprinting exercise on fat oxidation of trained and untrained males. [Methods] Fourteen trained and 14 untrained males ingested one capsule containing either green tea or cellulose with breakfast, lunch, and dinner, 24 hours before two exercise sessions. A fourth capsule was consumed 90 minutes before exercise after overnight NPO (nil per os). Participants performed a 20-minute interval sprinting cycling protocol, consisting of repeated bouts of 8-seconds of sprint cycling (at 65% of maximum power output) and 12-seconds of recovery (at 25% of maximum power output), followed by 75 minutes of post-exercise recovery. [Results] Fat oxidation was significantly greater in the resting condition after green tea ingestion (p < 0.05) compared with the placebo. Fat oxidation was also significantly increased post-exercise in the green tea, compared with the placebo condition (p < 0.01). During and after exercise the plasma glycerol levels significantly increased in both groups after green tea consumption and were significantly higher in the untrained group compared with the trained group (p < 0.05). Compared with the placebo, the plasma epinephrine levels were significantly higher for both groups in the green tea condition during and after exercise, however, norepinephrine levels were only significantly greater, p < 0.05, during and after exercise in the untrained group. [Conclusion] Green tea significantly increased resting and post-exercise fat oxidation and also elevated plasma glycerol and epinephrine levels during and after interval sprinting. Glycerol and norepinephrine levels during interval sprinting were significantly higher in the untrained group compared with the trained group. PMID:27298806

  1. The effect of sampling technique on PCR-based bacteriological results of bovine milk samples.

    PubMed

    Hiitiö, Heidi; Simojoki, Heli; Kalmus, Piret; Holopainen, Jani; Pyörälä, Satu; Taponen, Suvi

    2016-08-01

    The aim of the study was to evaluate the effect of sampling technique on the microbiological results of bovine milk samples using multiplex real-time PCR. Comparison was made between a technique where the milk sample was taken directly from the udder cistern of the udder quarter using a needle and vacuum tube and conventional sampling. The effect of different cycle threshold (Ct) cutoff limits on the results was also tested to estimate the amount of amplified DNA in the samples. A total of 113 quarters from 53 cows were tested pairwise using both techniques, and each sample was studied with real-time PCR. Sampling from the udder cistern reduced the number of species per sample compared with conventional sampling. In conventional samples, the number of positive Staphylococcus spp. results was over twice that of samples taken with the needle technique, indicating that most of the Staphylococcus spp. originated from the teat or environmental sources. The Ct values also showed that Staphylococcus spp. were present in most samples only in low numbers. Routine use of multiplex real-time PCR in mastitis diagnostics could benefit from critical evaluation of positive Staphylococcus spp. results with Ct values between 34.0 and 37.0. Our results emphasize the importance of a careful aseptic milk sampling technique and a microbiologically positive result for a milk sample should not be automatically interpreted as an intramammary infection or mastitis.

  2. Nanoscale Surface Characterization of Aqueous Copper Corrosion: Effects of Immersion Interval and Orthophosphate Concentration

    EPA Science Inventory

    Morphology changes for copper surfaces exposed to different water parameters were investigated at the nanoscale with atomic force microscopy (AFM), as influenced by changes in pH and the levels of orthophosphate ions. Synthetic water samples were designed to mimic physiological c...

  3. The effect of the interval-between-sessions on prefrontal transcranial direct current stimulation (tDCS) on cognitive outcomes: a systematic review and meta-analysis.

    PubMed

    Dedoncker, Josefien; Brunoni, Andre R; Baeken, Chris; Vanderhasselt, Marie-Anne

    2016-10-01

    Recently, there has been wide interest in the effects of transcranial direct current stimulation (tDCS) of the dorsolateral prefrontal cortex (DLPFC) on cognitive functioning. However, many methodological questions remain unanswered. One of them is whether the time interval between active and sham-controlled stimulation sessions, i.e. the interval between sessions (IBS), influences DLPFC tDCS effects on cognitive functioning. Therefore, a systematic review and meta-analysis was performed of experimental studies published in PubMed, Science Direct, and other databases from the first data available to February 2016. Single session sham-controlled within-subject studies reporting the effects of tDCS of the DLPFC on cognitive functioning in healthy controls and neuropsychiatric patients were included. Cognitive tasks were categorized in tasks assessing memory, attention, and executive functioning. Evaluation of 188 trials showed that anodal vs. sham tDCS significantly decreased response times and increased accuracy, and specifically for the executive functioning tasks, in a sample of healthy participants and neuropsychiatric patients (although a slightly different pattern of improvement was found in analyses for both samples separately). The effects of cathodal vs. sham tDCS (45 trials), on the other hand, were not significant. IBS ranged from less than 1 h to up to 1 week (i.e. cathodal tDCS) or 2 weeks (i.e. anodal tDCS). This IBS length had no influence on the estimated effect size when performing a meta-regression of IBS on reaction time and accuracy outcomes in all three cognitive categories, both for anodal and cathodal stimulation. Practical recommendations and limitations of the study are further discussed.

  4. The effect of the interval from PGF treatment to ovulation on embryo recovery and pregnancy rate in the mare.

    PubMed

    Cuervo-Arango, J; Mateu-Sánchez, S; Aguilar, J J; Nielsen, J M; Etcharren, V; Vettorazzi, M L; Newcombe, J R

    2015-05-01

    The objective of this study was to determine the effect of the interval from induced luteolysis to ovulation on fertility of mares from two different farms. At farm 1, 215 mares were inseminated with frozen/thawed semen during 513 estrous cycles over seven consecutive breeding seasons. Estrus was induced with analogues of PGF2α in 179 cycles. At farm 2, 375 embryo flushings were performed in 65 donor mares inseminated with fresh semen; of which, 327 were performed following artificial insemination after PGF-induced luteolysis. In both farms, the intervals from PGF treatment to ovulation (ITO) data were divided into three interval groups: less than 6 days, 6 to 8 days, and greater than 8 days. A mixed regression model was created to determine the effect of different factors on the pregnancy rate (PR) and embryo recovery rate (ERR). Of all factors analyzed, the ITO was the only one that significantly influenced the PR and ERR (P < 0.05). In farm 1, the PR of mares with an ITO of less than 6 days, 6 to 8 days, and greater than 8 days was 26.6%, 39.4%, and 55.9%, respectively (P = 0.01). The PR for mares inseminated after spontaneous luteolysis (without PGF) was 42.5%. In farm 2, the ERR of donor mares for the same ITO groups was 55.0%, 62.6%, and 73.7%, respectively (P = 0.02). The ERR for mares flushed after a previous spontaneous estrus was 75.0%. In conclusion, the ITO had a significant effect on the PR and ERR in the mare. Fertility was reduced as the ITO became shorter.

  5. The Influence of Prior Handling on the Effective CS-US Interval in Long-Trace Taste-Aversion Conditioning in Rats

    ERIC Educational Resources Information Center

    Hinderliter, Charles F.; Andrews, Amy; Misanin, James R.

    2012-01-01

    In conditioned taste aversion (CTA), a taste, the conditioned stimulus (CS), is paired with an illness-inducing stimulus, the unconditioned stimulus (US), to produce CS-US associations at very long (hours) intervals, a result that appears to violate the law of contiguity. The specific length of the maximum effective trace interval that has been…

  6. Tolerance to Effects of Cocaine on Behavior under a Response-Initiated Fixed-Interval Schedule

    ERIC Educational Resources Information Center

    Weaver, Matthew T.; Branch, Marc N.

    2008-01-01

    Tolerance to effects of cocaine can be modulated by schedules of reinforcement. With multiple ratio schedules, research has shown an inverse relationship between ratio requirement and amount of tolerance that resulted from daily administration of the drug. In contrast, tolerance to the effects of cocaine on behavior under multiple interval…

  7. Effects of Cocaine on Performance under Fixed-Interval Schedules with a Small Tandem Ratio Requirement

    ERIC Educational Resources Information Center

    Pinkston, Jonathan W.; Branch, Marc N.

    2004-01-01

    Daily administration of cocaine often results in the development of tolerance to its effects on responding maintained by fixed-ratio schedules. Such effects have been observed to be greater when the ratio value is small, whereas less or no tolerance has been observed at large ratio values. Similar schedule-parameter-dependent tolerance, however,…

  8. Lack of an Effect of Standard and Supratherapeutic Doses of Linezolid on QTc Interval Prolongation▿†

    PubMed Central

    Damle, Bharat; LaBadie, Robert R.; Cuozzo, Cheryl; Alvey, Christine; Choo, Heng Wee; Riley, Steve; Kirby, Deborah

    2011-01-01

    A double-blind, placebo-controlled, four-way crossover study was conducted in 40 subjects to assess the effect of linezolid on corrected QT (QTc) interval prolongation. Time-matched, placebo-corrected QT intervals were determined predose and at 0.5, 1 (end of infusion), 2, 4, 8, 12, and 24 h after intravenous dosing of linezolid 600 and 1,200 mg. Oral moxifloxacin at 400 mg was used as an active control. The pharmacokinetic profile of linezolid was also evaluated. At each time point, the upper bound of the 90% confidence interval (CI) for placebo-corrected QTcF values (i.e., QTc values adjusted for ventricular rate using the correction methods of Fridericia) for linezolid 600 and 1,200-mg doses were <10 ms, which indicates an absence of clinically significant QTc prolongation. At 2 and 4 h after the moxifloxacin dose, corresponding to the population Tmax, the lower bound of the two-sided 90% CI for QTcF when comparing moxifloxacin to placebo was >5 ms, indicating that the study was adequately sensitive to assess QTc prolongation. The pharmacokinetic profile of linezolid at 600 mg was consistent with previous observations. Systemic exposure to linezolid increased in a slightly more than dose-proportional manner at supratherapeutic doses, but the degree of nonlinearity was small. At a supratherapeutic single dose of 1,200 mg of linezolid, no treatment-related increase in adverse events was seen compared to 600 mg of linezolid, and no clinically meaningful effects on vital signs and safety laboratory evaluations were noted. PMID:21709083

  9. Patterns of Sexual Aggression in a Community Sample of Young Men: Risk Factors Associated with Persistence, Desistance, and Initiation Over a One Year Interval

    PubMed Central

    Abbey, Antonia; Wegner, Rhiana; Pierce, Jennifer; Jacques-Tiura, Angela J.

    2012-01-01

    Objective The goal of this study is to distinguish risk factors associated with young men's self-reports of continuing (persistence), stopping (desistance), and starting (initiation) sexual aggression against women over a one year time period. This study fills gaps in the literature not addressed in other studies by examining a wide range of predictor variables prospectively in a community sample. Method Single men age 18 to 35 were recruited through telephone sampling in a large metropolitan region. In person audio computer-assisted self interviews were completed at baseline and one year later (n = 423). Results By the follow-up interview, half of the participants reported engaging in some type of sexual activity with a woman when they knew she was unwilling. Discriminant function and analysis of variance demonstrated that persistent sexual aggressors had the most extreme scores on many baseline and follow-up measures including childhood victimization, social deviance, personality traits, frequency of misperception of women's sexual intent, and expectancies about alcohol's effects. At follow-up, desisters had fewer sexual partners than did persisters. Also at follow-up, initiators misperceived more women's sexual intentions, had stronger alcohol expectancies, drank more alcohol in sexual situations, and were with women who drank more alcohol as compared to nonperpetrators. Conclusions Given the extremely high rates of self-reported sexual aggression, universal prevention programs are needed. Targeted interventions should focus on youth who were victimized in childhood, engage in delinquent behavior, are narcissistic and unconcerned about others, enjoy impersonal sex, drink heavily, and believe that alcohol enhances sexuality. PMID:22272382

  10. Effect of crabgrass (Digitaria ciliaris) hay harvest interval on forage quality and performance of growing calves fed mixed diets.

    PubMed

    Beck, P A; Hutchison, S; Stewart, C B; Shockey, J D; Gunter, S A

    2007-02-01

    effective degradability of DM and NDF of hays, but DM disappearance of the total diet did not differ (P > or = 0.35). In the conditions of this study, increasing harvest interval of crabgrass hay from 21 to 49 d had no deleterious impact on animal performance or efficiency of gain when fed to growing calves in a high-concentrate mixture.

  11. How to Learn Effectively in Medical School: Test Yourself, Learn Actively, and Repeat in Intervals

    PubMed Central

    Augustin, Marc

    2014-01-01

    Students in medical school often feel overwhelmed by the excessive amount of factual knowledge they are obliged to learn. Although a large body of research on effective learning methods is published, scientifically based learning strategies are not a standard part of the curriculum in medical school. Students are largely unaware of how to learn successfully and improve memory. This review outlines three fundamental methods that benefit learning: the testing effect, active recall, and spaced repetition. The review summarizes practical learning strategies to learn effectively and optimize long-term retention of factual knowledge. PMID:24910566

  12. Pigeons' Choices between Fixed-Interval and Random-Interval Schedules: Utility of Variability?

    ERIC Educational Resources Information Center

    Andrzejewski, Matthew E.; Cardinal, Claudia D.; Field, Douglas P.; Flannery, Barbara A.; Johnson, Michael; Bailey, Kathleen; Hineline, Philip N.

    2005-01-01

    Pigeons' choosing between fixed-interval and random-interval schedules of reinforcement was investigated in three experiments using a discrete-trial procedure. In all three experiments, the random-interval schedule was generated by sampling a probability distribution at an interval (and in multiples of the interval) equal to that of the…

  13. Using Ancillary Information to Reduce Sample Size in Discovery Sampling and the Effects of Measurement Error

    SciTech Connect

    Axelrod, M

    2005-08-18

    Discovery sampling is a tool used in a discovery auditing. The purpose of such an audit is to provide evidence that some (usually large) inventory of items complies with a defined set of criteria by inspecting (or measuring) a representative sample drawn from the inventory. If any of the items in the sample fail compliance (defective items), then the audit has discovered an impropriety, which often triggers some action. However finding defective items in a sample is an unusual event--auditors expect the inventory to be in compliance because they come to the audit with an ''innocent until proven guilty attitude''. As part of their work product, the auditors must provide a confidence statement about compliance level of the inventory. Clearly the more items they inspect, the greater their confidence, but more inspection means more cost. Audit costs can be purely economic, but in some cases, the cost is political because more inspection means more intrusion, which communicates an attitude of distrust. Thus, auditors have every incentive to minimize the number of items in the sample. Indeed, in some cases the sample size can be specifically limited by a prior agreement or an ongoing policy. Statements of confidence about the results of a discovery sample generally use the method of confidence intervals. After finding no defectives in the sample, the auditors provide a range of values that bracket the number of defective items that could credibly be in the inventory. They also state a level of confidence for the interval, usually 90% or 95%. For example, the auditors might say: ''We believe that this inventory of 1,000 items contains no more than 10 defectives with a confidence of 95%''. Frequently clients ask their auditors questions such as: How many items do you need to measure to be 95% confident that there are no more than 10 defectives in the entire inventory? Sometimes when the auditors answer with big numbers like ''300'', their clients balk. They balk because a

  14. Effects of low and high cadence interval training on power output in flat and uphill cycling time-trials.

    PubMed

    Nimmerichter, Alfred; Eston, Roger; Bachl, Norbert; Williams, Craig

    2012-01-01

    This study tested the effects of low-cadence (60 rev min(-1)) uphill (Int(60)) or high-cadence (100 rev min(-1)) level-ground (Int(100)) interval training on power output (PO) during 20-min uphill (TT(up)) and flat (TT(flat)) time-trials. Eighteen male cyclists ([Formula: see text]: 58.6 ± 5.4 mL min(-1) kg(-1)) were randomly assigned to Int(60), Int(100) or a control group (Con). The interval training comprised two training sessions per week over 4 weeks, which consisted of six bouts of 5 min at the PO corresponding to the respiratory compensation point (RCP). For the control group, no interval training was conducted. A two-factor ANOVA revealed significant increases on performance measures obtained from a laboratory-graded exercise test (GXT) (P (max): 2.8 ± 3.0%; p < 0.01; PO and [Formula: see text] at RCP: 3.6 ± 6.3% and 4.7 ± 8.2%, respectively; p < 0.05; and [Formula: see text] at ventilatory threshold: 4.9 ± 5.6%; p < 0.01), with no significant group effects. Significant interactions between group and uphill and flat time-trial, pre- versus post-training on PO were observed (p < 0.05). Int(60) increased PO during both TT(up) (4.4 ± 5.3%) and TT(flat) (1.5 ± 4.5%). The changes were -1.3 ± 3.6, 2.6 ± 6.0% for Int(100) and 4.0 ± 4.6%, -3.5 ± 5.4% for Con during TT(up) and TT(flat), respectively. PO was significantly higher during TT(up) than TT(flat) (4.4 ± 6.0; 6.3 ± 5.6%; pre and post-training, respectively; p < 0.001). These findings suggest that higher forces during the low-cadence intervals are potentially beneficial to improve performance. In contrast to the GXT, the time-trials are ecologically valid to detect specific performance adaptations.

  15. [The importance of electrocardiography in the development of new drugs--prolonged QT intervals as indicators of adverse effects].

    PubMed

    Jerie, P; Vít, P

    2002-12-01

    Both experimental animal studies and clinical observations have shown that drugs from various indication areas, such as psychotropic agents and antiarrhythmics can induce disturbances of cardiac rhythm and electrocardiographic abnormalities. Particularly, QT interval prolongation is associated with distinctive polymorphic ventricular tachycardias and often causes syncopes or cardiac arrest that represent a high risk of recurrent events including sudden death. In the last decade, several drugs in different indication areas, possessing these effects were withdrawn from the market and approvals were postponed or even refused. These events led to higher regulatory requirements on the cardiovascular safety of new drugs, with a special emphasis on prolongation of the QT interval. This article reviews the use of preclinical and clinical electrocardiography, as well as the current problems during development of novel drugs and future strategy in clinical studies. Even though ECG proved to be a powerful and reliable tool for detection of cardiac serious adverse effects during development of drugs, it also needs to be used with increased attention in all patients treated with new drugs and drug combinations in clinical and ambulatory practice in order to ensure their safe use in a wide population, as well as in patients with concurrent cardiac risk factors.

  16. Effects of continuous and interval running training on serum growth and cortisol hormones in junior male basketball players.

    PubMed

    Büyükyazi, G; Karamizrak, S O; Islegen, C

    2003-01-01

    Effects of two different eight-week aerobic training programs consisting of continuous (CR) or extensive interval running (IR) on serum growth (GH) and cortisol hormones in 33 male basketball players aged 15-16 were assessed. The CR group ran 4.8 km and the IR group ran 4 x 1.2 km, using equal work-to-rest ratio, three times per week. Aerobic power scores of all subjects and anaerobic power marks of the training subjects increased (p<0.01). Upon exertion, though serum GH levels increased in both exercise groups (p<0.01) prior to and following training; cortisol levels increased only in the IR group prior to training, and in both exercise groups following training (p<0.05). Following the eight week period, resting cortisol levels rose in the training (p<0.05) and control (p<0.01) groups. To conclude, an 8-week training program consisting of continuous or extensive interval running has been effective on acute GH and cortisol secretion in 15-16 year-old male athletes.

  17. Proportion of the Litter Farrowed, Litter Size, and Progesterone and Estradiol Effects on Piglet Birth Intervals and Stillbirths

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Stillbirth in swine ranges from 2 to 9%, resulting in a significant loss of piglets. Previous studies clearly indicate a relationship between prolonged birth intervals and stillbirth, but factors influencing birth intervals are not fully known. To characterize birth intervals and stillbirth, farrowi...

  18. Effects of Improvements in Interval Timing on the Mathematics Achievement of Elementary School Students

    ERIC Educational Resources Information Center

    Taub, Gordon E.; McGrew, Kevin S.; Keith, Timothy Z.

    2015-01-01

    This article examines the effect of improvements in timing/rhythmicity on mathematics achievement. A total of 86 participants attending 1st through 4th grades completed pre- and posttest measures of mathematics achievement from the Woodcock-Johnson III Tests of Achievement. Students in the experimental group participated in a 4-week intervention…

  19. High-intensity interval training (HIT) for effective and time-efficient pre-surgical exercise interventions.

    PubMed

    Weston, Matthew; Weston, Kathryn L; Prentis, James M; Snowden, Chris P

    2016-01-01

    The advancement of perioperative medicine is leading to greater diversity in development of pre-surgical interventions, implemented to reduce patient surgical risk and enhance post-surgical recovery. Of these interventions, the prescription of pre-operative exercise training is gathering momentum as a realistic means for enhancing patient surgical outcome. Indeed, the general benefits of exercise training have the potential to pre-operatively optimise several pre-surgical risks factors, including cardiorespiratory function, frailty and cognitive function. Any exercise programme incorporated into the pre-operative pathway of care needs to be effective and time efficient in that any fitness gains are achievable in the limited period between the decision for surgery and operation (e.g. 4 weeks). Fortunately, there is a large volume of research describing effective and time-efficient exercise training programmes within the discipline of sports science. Accordingly, the objective of our commentary is to synthesise contemporary exercise training research, both from non-clinical and clinical populations, with the overarching aim of informing the development of effective and time-efficient pre-surgical exercise training programmes. The development of such exercise training programmes requires the careful consideration of several key principles, namely frequency, intensity, time, type and progression of exercise. Therefore, in light of more recent evidence demonstrating the effectiveness and time efficiency of high-intensity interval training-which involves brief bouts of intense exercise interspersed with longer recovery periods-the principles of exercise training programme design will be discussed mainly in the context of such high-intensity interval training programmes. Other issues pertinent to the development, implementation and evaluation of pre-operative exercise training programmes, such as individual exercise prescription, training session monitoring and potential

  20. High-intensity interval training (HIT) for effective and time-efficient pre-surgical exercise interventions.

    PubMed

    Weston, Matthew; Weston, Kathryn L; Prentis, James M; Snowden, Chris P

    2016-01-01

    The advancement of perioperative medicine is leading to greater diversity in development of pre-surgical interventions, implemented to reduce patient surgical risk and enhance post-surgical recovery. Of these interventions, the prescription of pre-operative exercise training is gathering momentum as a realistic means for enhancing patient surgical outcome. Indeed, the general benefits of exercise training have the potential to pre-operatively optimise several pre-surgical risks factors, including cardiorespiratory function, frailty and cognitive function. Any exercise programme incorporated into the pre-operative pathway of care needs to be effective and time efficient in that any fitness gains are achievable in the limited period between the decision for surgery and operation (e.g. 4 weeks). Fortunately, there is a large volume of research describing effective and time-efficient exercise training programmes within the discipline of sports science. Accordingly, the objective of our commentary is to synthesise contemporary exercise training research, both from non-clinical and clinical populations, with the overarching aim of informing the development of effective and time-efficient pre-surgical exercise training programmes. The development of such exercise training programmes requires the careful consideration of several key principles, namely frequency, intensity, time, type and progression of exercise. Therefore, in light of more recent evidence demonstrating the effectiveness and time efficiency of high-intensity interval training-which involves brief bouts of intense exercise interspersed with longer recovery periods-the principles of exercise training programme design will be discussed mainly in the context of such high-intensity interval training programmes. Other issues pertinent to the development, implementation and evaluation of pre-operative exercise training programmes, such as individual exercise prescription, training session monitoring and potential

  1. Effects of posture on exercise performance - Measurement by systolic time intervals.

    NASA Technical Reports Server (NTRS)

    Spodick, D. H.; Quarry-Pigott, V. M.

    1973-01-01

    Because posture significantly influences cardiac performance, the effects of moderate supine and upright ergometer exercise were compared on the basis of proportional (+37%) rate increments over resting control. Supine exercise produced significant decreases in left ventricular ejection time (LVET), pre-ejection period (PEP), and isovolumic contraction time (IVCT). Ejection time index (ETI) and corrected ejection time (LVETc) did not change significantly. Upright exercise produced greater decreases in PEP and LVET, but despite the rate increase there was no change in LVET, which resulted in sharp increases in ETI and LVETc. The discordant directional effects on LVET and its rate-correcting indices between the two postures were consistent with hemodynamic studies demonstrating lack of stroke volume change during supine exercise and increased stroke volume over control during light to moderate upright exercise.

  2. Interval exercise training in cystic fibrosis -- effects on exercise capacity in severely affected adults.

    PubMed

    Gruber, Wolfgang; Orenstein, David M; Braumann, Klaus M; Beneke, Ralph

    2014-01-01

    The aims of the present study were to investigate the effects of IT on lung function power (P) and oxygen uptake (VO2) at peak performance (peak) and ventilatory anaerobic threshold (VAT) in CF patients who were unable to participate in a standard exercise program (SEP) and to compare these IT responses with corresponding effects in CF patients performing SEP. 20 patients (FEV1 25.5 ± 7.5%; pred; SpO2 < 90% at rest or P lower than 0.3 W/kg) who were unable to participate in SEP were allocated to IT (5 × 20 min weekly). 23 patients (FEV1 31.6 ± 4.2%; p < 0.05) did 5 × 45 min per week of SEP. Lung function remained unchanged in both groups. VO2peak and PVAT increased in both groups (p < 0.05). However, only after the SEP an increase in Ppeak (p < 0.05) and only after IT a higher VO2VAT (p < 0.05) were found. Compared to SEP, IT improved submaximal exercise capacity to a greater extent whereas responsiveness on peak performance was higher in SEP. This seems to indicate a specific potential of IT for positive peripheral muscular adaptations in spite of diminishing potential of pulmonary improvement. IT represents an alternative, effective and safe training regimen with patients with CF and severe lung disease, with a greater potential than SEP. PMID:23863518

  3. Estimating incremental cost-effectiveness ratios and their confidence intervals with different terminating events for survival time and costs.

    PubMed

    Chen, Shuai; Zhao, Hongwei

    2013-07-01

    Cost-effectiveness analysis (CEA) is an important component of the economic evaluation of new treatment options. In many clinical and observational studies of costs, censored data pose challenges to the CEA. We consider a special situation where the terminating events for the survival time and costs are different. Traditional methods for statistical inference offer no means for dealing with censored data in these circumstances. To address this gap, we propose a new method for deriving the confidence interval for the incremental cost-effectiveness ratio. The simulation studies and real data example show that our method performs very well for some practical settings, revealing a great potential for application to actual settings in which terminating events for the survival time and costs differ.

  4. A simple, physiologically-based model of sea turtle remigration intervals and nesting population dynamics: Effects of temperature.

    PubMed

    Neeman, Noga; Spotila, James R; O'Connor, Michael P

    2015-09-01

    Variation in the yearly number of sea turtles nesting at rookeries can interfere with population estimates and obscure real population dynamics. Previous theoretical models suggested that this variation in nesting numbers may be driven by changes in resources at the foraging grounds. We developed a physiologically-based model that uses temperatures at foraging sites to predict foraging conditions, resource accumulation, remigration probabilities, and, ultimately, nesting numbers for a stable population of sea turtles. We used this model to explore several scenarios of temperature variation at the foraging grounds, including one-year perturbations and cyclical temperature oscillations. We found that thermally driven resource variation can indeed synchronize nesting in groups of turtles, creating cohorts, but that these cohorts tend to break down over 5-10 years unless regenerated by environmental conditions. Cohorts were broken down faster at lower temperatures. One-year perturbations of low temperature had a synchronizing effect on nesting the following year, while high temperature perturbations tended to delay nesting in a less synchronized way. Cyclical temperatures lead to cyclical responses both in nesting numbers and remigration intervals, with the amplitude and lag of the response depending on the duration of the cycle. Overall, model behavior is consistent with observations at nesting beaches. Future work should focus on refining the model to fit particular nesting populations and testing further whether or not it may be used to predict observed nesting numbers and remigration intervals.

  5. Response additivity: effects of superimposed free reinforcement on a variable-interval baseline.

    PubMed

    Boakes, R A; Halliday, M S; Poli, M

    1975-03-01

    Three experiments examined the effects of superimposing free reinforcement (Free VI 30-sec) on behavior maintained by a response dependent mult VI 2-min VI 2-min schedule of reinforcement. Experiment I used pigeons as subjects, key pecking as the response, and colors of response key as the stimuli associated with the multiple-schedule components. When free reinforcement was added during only one component (Differential condition) a large and highly significant increase in response rate developed in this component. Adding free reinforcement during both components (Nondifferential condition) produced smaller and far less-consistent effects. An entirely different pattern of results was obtained in two subsequent experiments, where similar procedures and reinforcement conditions were used with rats as subjects and bar pressing as the response. In both Experiments II and III, response rates decreased to the stimulus associated with added free reinforcement in the Differential condition. These findings are interpreted as the result of interactions between behavior maintained by response-reinforcer contingencies and behavior maintained by stimulus-reinforcer contingencies. As such, they support the main assumption of an autoshaping theory of behavioral contrast, that additivity of responding generated by the two kinds of contingency can occur only in situations favorable to autoshaping.

  6. Effects of sampling artifacts on occupational samples of diesel particulate matter.

    PubMed

    Noll, James; Birch, M Eileen

    2008-07-15

    Total carbon (TC) is sometimes used to measure or characterize diesel particulate matter (DPM) in occupational settings such as underground mines. DPM samples are collected on quartz fiber filters. When using quartz fiber filters, adsorption of gas phase organic carbon (OC) has been reported, causing a positive bias in the particulate TC results (adsorption artifact). Most of the data on the sampling artifacts and corrections applyto environmental air sampling, where samples are collected at a much higher filter face velocity and the OC concentrations are generally much lower relative to occupational sampling. In this study, we investigated the effects of adsorption artifact on samples from occupational settings. Samples were collected with and without denuders to determine the amount of gas phase OC collected and the accuracy of certain corrections. In underground stone mines, the adsorption artifact was found to positively bias the particulate TC by greater than 20% for filter loadings below 25 microg/cm2 TC (8-h time weighted average = 262 microg/m3). The tandem filter correction reduced the effect of the artifact, as high as 60% of the TC value, to less than 11% for laboratory data. It also significantly reduced the effect of the artifact obtained for field samples.

  7. The Effect of Item Stratification in Multiple Matrix Sampling.

    ERIC Educational Resources Information Center

    Myerberg, N. James

    The effect of stratified sampling of items on the estimation of test score distribution parameters by multiple matrix sampling was studied. Item difficulty and/or interitem correlations were the bases of stratification. Various item iniverses were created by computer simulation and sampled according to several plans. The results indicate that…

  8. Effect of goal difficulty, goal specificity and duration of practice time intervals on muscular endurance performance.

    PubMed

    Bar-Eli, M; Tenenbaum, G; Pie, J S; Btesh, Y; Almog, A

    1997-04-01

    The aims of this study were to explore the relationships between goal specificity, goal difficulty and performance, and to determine if setting unrealistic goals would produce decreases in performance. The subjects were high school students from 15 schools and an attempt was made to control for the effects of social comparison. The schools were randomly assigned to one of 15 conditions representing five levels of goal conditions-namely, 'do' (no goals), 'do your best', 'improve by 10%' (easy), 'improve by 20%' (difficult/ realistic) and 'improve by 40%' (improbable/unattainable)-and three levels of practice duration (4, 6 and 8 weeks). This design consisted of nesting goal difficulty within practice duration, which enabled an examination of the goal specificity and goal attainability/difficulty hypotheses proposed by Locke and Latham (1985). A 5 x 3 factorial ANCOVA was applied to the post-baseline sit-up gain scores. The results indicated that all specific groups performed better than all non-specific groups. In addition, across practice durations the difficult/realistic group exhibited the greatest increase in performance, followed by the easy group. The performance gains of the improbable/unattainable group were substantially less compared with the difficult/ realistic group after 4 and 6 weeks, but not after 8 weeks of practice. These results are in line with both the goal specificity and goal difficulty hypotheses derived from the application of Locke's goal-setting theory to sport.

  9. Digitally available interval-specific rock-sample data compiled from historical records, Nevada National Security Site and vicinity, Nye County, Nevada

    USGS Publications Warehouse

    Wood, David B.

    2007-11-01

    Between 1951 and 1992, 828 underground tests were conducted on the Nevada National Security Site, Nye County, Nevada. Prior to and following these nuclear tests, holes were drilled and mined to collect rock samples. These samples are organized and stored by depth of borehole or drift at the U.S. Geological Survey Core Library and Data Center at Mercury, Nevada, on the Nevada National Security Site. From these rock samples, rock properties were analyzed and interpreted and compiled into project files and in published reports that are maintained at the Core Library and at the U.S. Geological Survey office in Henderson, Nevada. These rock-sample data include lithologic descriptions, physical and mechanical properties, and fracture characteristics. Hydraulic properties also were compiled from holes completed in the water table. Rock samples are irreplaceable because pre-test, in-place conditions cannot be recreated and samples can not be recollected from the many holes destroyed by testing. Documenting these data in a published report will ensure availability for future investigators.

  10. Digitally Available Interval-Specific Rock-Sample Data Compiled from Historical Records, Nevada Test Site and Vicinity, Nye County, Nevada.

    SciTech Connect

    David B. Wood

    2007-10-24

    Between 1951 and 1992, 828 underground tests were conducted on the Nevada Test Site, Nye County, Nevada. Prior to and following these nuclear tests, holes were drilled and mined to collect rock samples. These samples are organized and stored by depth of borehole or drift at the U.S. Geological Survey Core Library and Data Center at Mercury, Nevada, on the Nevada Test Site. From these rock samples, rock properties were analyzed and interpreted and compiled into project files and in published reports that are maintained at the Core Library and at the U.S. Geological Survey office in Henderson, Nevada. These rock-sample data include lithologic descriptions, physical and mechanical properties, and fracture characteristics. Hydraulic properties also were compiled from holes completed in the water table. Rock samples are irreplaceable because pre-test, in-place conditions cannot be recreated and samples cannot be recollected from the many holes destroyed by testing. Documenting these data in a published report will ensure availability for future investigators.

  11. Digitally Available Interval-Specific Rock-Sample Data Compiled from Historical Records, Nevada Test Site and Vicinity, Nye County, Nevada

    SciTech Connect

    David B. Wood

    2009-10-08

    Between 1951 and 1992, underground nuclear weapons testing was conducted at 828 sites on the Nevada Test Site, Nye County, Nevada. Prior to and following these nuclear tests, holes were drilled and mined to collect rock samples. These samples are organized and stored by depth of borehole or drift at the U.S. Geological Survey Core Library and Data Center at Mercury, Nevada, on the Nevada Test Site. From these rock samples, rock properties were analyzed and interpreted and compiled into project files and in published reports that are maintained at the Core Library and at the U.S. Geological Survey office in Henderson, Nevada. These rock-sample data include lithologic descriptions, physical and mechanical properties, and fracture characteristics. Hydraulic properties also were compiled from holes completed in the water table. Rock samples are irreplaceable because pre-test, in-place conditions cannot be recreated and samples cannot be recollected from the many holes destroyed by testing. Documenting these data in a published report will ensure availability for future investigators.

  12. The effects of birth order and birth interval on the phenotypic expression of autism spectrum disorder.

    PubMed

    Martin, Loren A; Horriat, Narges L

    2012-01-01

    A rise in the prevalence of diagnosed cases of autism spectrum disorder (ASD) has been reported in several studies in recent years. While this rise in ASD prevalence is at least partially related to increased awareness and broadened diagnostic criteria, the role of environmental factors cannot be ruled out, especially considering that the cause of most cases of ASD remains unknown. The study of families with multiple affected children can provide clues about ASD etiology. While the majority of research on ASD multiplex families has focused on identifying genetic anomalies that may underlie the disorder, the study of symptom severity across ASD birth order may provide evidence for environmental factors in ASD. We compared social and cognitive measures of behavior between over 300 first and second affected siblings within multiplex autism families obtained from the Autism Genetic Resource Exchange dataset. Measures included nonverbal IQ assessed with the Ravens Colored Progressive Matrices, verbal IQ assessed with the Peabody Picture Vocabulary Test, and autism severity assessed with the Social Responsiveness Scale (SRS), an instrument established as a quantitative measure of autism. The results indicated that females were more severely impacted by ASD than males, especially first affected siblings. When first and second affected siblings were compared, significant declines in nonverbal and verbal IQ scores were observed. In addition, SRS results demonstrated a significant increase in autism severity between first and second affected siblings consistent with an overall decline in function as indicated by the IQ data. These results remained significant after controlling for the age and sex of the siblings. Surprisingly, the SRS scores were found to only be significant when the age difference between siblings was less than 2 years. These results suggest that some cases of ASD are influenced by a dosage effect involving unknown epigenetic, environmental, and

  13. The effects of birth order and birth interval on the phenotypic expression of autism spectrum disorder.

    PubMed

    Martin, Loren A; Horriat, Narges L

    2012-01-01

    A rise in the prevalence of diagnosed cases of autism spectrum disorder (ASD) has been reported in several studies in recent years. While this rise in ASD prevalence is at least partially related to increased awareness and broadened diagnostic criteria, the role of environmental factors cannot be ruled out, especially considering that the cause of most cases of ASD remains unknown. The study of families with multiple affected children can provide clues about ASD etiology. While the majority of research on ASD multiplex families has focused on identifying genetic anomalies that may underlie the disorder, the study of symptom severity across ASD birth order may provide evidence for environmental factors in ASD. We compared social and cognitive measures of behavior between over 300 first and second affected siblings within multiplex autism families obtained from the Autism Genetic Resource Exchange dataset. Measures included nonverbal IQ assessed with the Ravens Colored Progressive Matrices, verbal IQ assessed with the Peabody Picture Vocabulary Test, and autism severity assessed with the Social Responsiveness Scale (SRS), an instrument established as a quantitative measure of autism. The results indicated that females were more severely impacted by ASD than males, especially first affected siblings. When first and second affected siblings were compared, significant declines in nonverbal and verbal IQ scores were observed. In addition, SRS results demonstrated a significant increase in autism severity between first and second affected siblings consistent with an overall decline in function as indicated by the IQ data. These results remained significant after controlling for the age and sex of the siblings. Surprisingly, the SRS scores were found to only be significant when the age difference between siblings was less than 2 years. These results suggest that some cases of ASD are influenced by a dosage effect involving unknown epigenetic, environmental, and

  14. Subjective probability intervals: how to reduce overconfidence by interval evaluation.

    PubMed

    Winman, Anders; Hansson, Patrik; Juslin, Peter

    2004-11-01

    Format dependence implies that assessment of the same subjective probability distribution produces different conclusions about over- or underconfidence depending on the assessment format. In 2 experiments, the authors demonstrate that the overconfidence bias that occurs when participants produce intervals for an uncertain quantity is almost abolished when they evaluate the probability that the same intervals include the quantity. The authors successfully apply a method for adaptive adjustment of probability intervals as a debiasing tool and discuss a tentative explanation in terms of a naive sampling model. According to this view, people report their experiences accurately, but they are naive in that they treat both sample proportion and sample dispersion as unbiased estimators, yielding small bias in probability evaluation but strong bias in interval production. PMID:15521796

  15. Effects of time of suckling during the solar day on duration of the postpartum anovulatory interval in Brahman x Hereford (F1) cows.

    PubMed

    Gazal, O S; Guzman-Vega, G A; Williams, G L

    1999-05-01

    Previously published reports have indicated that postpartum anovulatory intervals can be markedly reduced and rebreeding performance enhanced in Bos taurus cows by eliminating nighttime suckling. We sought to confirm this hypothesis by examining the effects of day, nighttime, and ad libitum suckling on suckling behavior of calves, duration of the postpartum anovulatory interval, and pregnancy rates in 45 fall-calving Brahman x Hereford (F1) cows. Beginning on d 9 to 12 postpartum, calves were removed from lactating cows from 0700 to 1900 (Night-Suckled, n = 15) or from 1900 to 0700 (Day-Suckled, n = 15), or remained with their dams continuously (Ad Libitum-Suckled, n = 15). Cows in each group were maintained with fertile Angus bulls from d 10 postpartum until the first normal luteal phase or 100 d postpartum, whichever occurred first. Cows were observed for estrous behavior twice daily, and jugular blood samples were collected twice weekly for the determination of serum progesterone concentration. Mean number of suckling episodes per 24 h was greater (P < .0001) for the Ad Libitum-Suckled group than either Night- or Day-Suckled groups (5.9+/-.42 vs 3.8+/-.14, and 3.9+/-.32, respectively). Hourly analysis of suckling episodes in the Ad Libitum group indicated that they were not skewed toward a particular period, with suckling occurring at a periodicity of 4 to 6 h. Intervals to the first rise in progesterone > or = 1 ng/mL (32+/-2.5, 32+/-4.5, and 31+/-1.7 d, respectively), first normal luteal phase (38+/-3.1, 38+/-3.8, and 37+/-2.5 d, respectively), and first estrus (43+/-3.5, 40+/-3.9, and 36+/-1.1 d, respectively) did not differ (P > .05) among the three groups. Similarly, cumulative pregnancy rates within 100 d after calving did not differ (P > .05). These results in Bos indicus x Bos taurus (F1) cattle do not support the previous conclusions in Bos taurus that eliminating nighttime suckling reduces the postpartum anovulatory interval. PMID:10340568

  16. Effect on tumour control of time interval between surgery and postoperative radiotherapy: an empirical approach using Monte Carlo simulation

    NASA Astrophysics Data System (ADS)

    Al-Dweri, Feras M. O.; Guirado, Damián; Lallena, Antonio M.; Pedraza, Vicente

    2004-07-01

    In this work, a procedure, based on Monte Carlo techniques, to analyse the effect on the tumour control probability of the time interval between surgery and postoperative radiotherapy is presented. The approach includes the tumour growth as well as the survival of tumour cells undergoing fractionated radiotherapy. Both processes are described in terms of the binomial distribution. We have considered two different growth models, exponential and Gompertz, the parameters of which have been fixed to reproduce the clinical outcome corresponding to a retrospective study for patients with head and neck squamous cell carcinomas. In the cases analysed, we have not found significant differences between the results obtained for both growth models. The mean doubling times found for residual clonogens after surgery are less than 40 days. The rate of decrease in local control is around 0.09% per day of delay between surgery and radiotherapy and the corresponding time factor is about 0.11 Gy per day.

  17. The effects of high-intensity interval training on glucose regulation and insulin resistance: a meta-analysis.

    PubMed

    Jelleyman, C; Yates, T; O'Donovan, G; Gray, L J; King, J A; Khunti, K; Davies, M J

    2015-11-01

    The aim of this meta-analysis was to quantify the effects of high-intensity interval training (HIIT) on markers of glucose regulation and insulin resistance compared with control conditions (CON) or continuous training (CT). Databases were searched for HIIT interventions based upon the inclusion criteria: training ≥2 weeks, adult participants and outcome measurements that included insulin resistance, fasting glucose, HbA1c or fasting insulin. Dual interventions and participants with type 1 diabetes were excluded. Fifty studies were included. There was a reduction in insulin resistance following HIIT compared with both CON and CT (HIIT vs. CON: standardized mean difference [SMD] = -0.49, confidence intervals [CIs] -0.87 to -0.12, P = 0.009; CT: SMD = -0.35, -0.68 to -0.02, P = 0.036). Compared with CON, HbA1c decreased by 0.19% (-0.36 to -0.03, P = 0.021) and body weight decreased by 1.3 kg (-1.9 to -0.7, P < 0.001). There were no statistically significant differences between groups in other outcomes overall. However, participants at risk of or with type 2 diabetes experienced reductions in fasting glucose (-0.92 mmol L(-1), -1.22 to -0.62, P < 0.001) compared with CON. HIIT appears effective at improving metabolic health, particularly in those at risk of or with type 2 diabetes. Larger randomized controlled trials of longer duration than those included in this meta-analysis are required to confirm these results.

  18. Cardioprotective Effect of High Intensity Interval Training and Nitric Oxide Metabolites (NO2−, NO3−)

    PubMed Central

    FALLAHI, Aliasghar; GAEINI, Abbasali; SHEKARFROUSH, Shahnaz; KHOSHBATEN, Ali

    2015-01-01

    Background: The aim of this study was to investigate the effects of High-Intensity Interval Training (HIIT) on nitric oxide metabolites (NO2−, NO3−) and myocardial infarct size after Ischemia/Reperfusion (I/R) injury in healthy male rats. Methods: A total of 44 Wistar rats were randomly divided into 4 groups including HIIT (n=8), HIIT + IR protocol (n=14), control (n=8), and control + IR (n=14). Each training session of HIIT consisted of 1 hour of exercise in three stages: 6-minute running at 50–60% VO2max for warm-up; 7 intervals of 7-minute running on treadmill with a slope of 5° to 20° (4 minutes with an intensity of 80–100% VO2max and 3 minutes at 50–60% VO2max); and 5-minute running at 50–60% VO2max for cool-down. The control group did not participate in any exercise program. Nitric Oxide (NO) and its metabolites were measured by using Griess reaction test. Results: The results showed that eight weeks of exercise training exerted a significantly increasing effect on nitrite (8.55 μmol per liter, equivalent to 34.79%), nitrate (62.02 μmol per liter, equivalent to 149.48%), and NOx (66 μmol per liter, equivalent to 98.11%) in the HIIT group compared with the control group. The results showed myocardial infract size (IS) was significantly smaller (23.2%, P<0.001) in the exercise training group compared with the control group. Conclusion: Incremental changes in NO-NO3−, NO2− axis are one of mechanisms through which HIIT program can protect the heart from I/R injury and decrease myocardial infarction. PMID:26587502

  19. The effects of high-intensity interval training on glucose regulation and insulin resistance: a meta-analysis.

    PubMed

    Jelleyman, C; Yates, T; O'Donovan, G; Gray, L J; King, J A; Khunti, K; Davies, M J

    2015-11-01

    The aim of this meta-analysis was to quantify the effects of high-intensity interval training (HIIT) on markers of glucose regulation and insulin resistance compared with control conditions (CON) or continuous training (CT). Databases were searched for HIIT interventions based upon the inclusion criteria: training ≥2 weeks, adult participants and outcome measurements that included insulin resistance, fasting glucose, HbA1c or fasting insulin. Dual interventions and participants with type 1 diabetes were excluded. Fifty studies were included. There was a reduction in insulin resistance following HIIT compared with both CON and CT (HIIT vs. CON: standardized mean difference [SMD] = -0.49, confidence intervals [CIs] -0.87 to -0.12, P = 0.009; CT: SMD = -0.35, -0.68 to -0.02, P = 0.036). Compared with CON, HbA1c decreased by 0.19% (-0.36 to -0.03, P = 0.021) and body weight decreased by 1.3 kg (-1.9 to -0.7, P < 0.001). There were no statistically significant differences between groups in other outcomes overall. However, participants at risk of or with type 2 diabetes experienced reductions in fasting glucose (-0.92 mmol L(-1), -1.22 to -0.62, P < 0.001) compared with CON. HIIT appears effective at improving metabolic health, particularly in those at risk of or with type 2 diabetes. Larger randomized controlled trials of longer duration than those included in this meta-analysis are required to confirm these results. PMID:26481101

  20. Methods to infer the compliance status with interval-averaged and with instantaneous occupational exposure limits from the results of longer-duration, integrated air sampling.

    PubMed

    Hunsaker, Harry A

    2016-01-01

    The duration of integrated air sampling for a substance may exceed the time frame of a substance's occupational exposure limit. Nonetheless, the compliance status of a limit may be inferred, under some circumstances, by the application of certain methods to the results of longer-duration samples. The purpose of this article is to define the inference methods and to illustrate their utility with actual and hypothetical examples. A review of articles and reports in U.S.-based Industrial Hygiene publications and databases revealed that the methods often were not but arguably should have been applied. Also revealed were inappropriate conclusions about the compliance status with exposure limits. Among the benefits of employing the inference methods is gaining information on exposures that might otherwise be overlooked. This article discusses the potential limitations of using the methods, and highlights some of the challenges of using integrated air sampling for assessing compliance with shorter-term exposure limits. PMID:26366477

  1. Effect of variation in PQ interval on patterns of atrioventricular valve motion and flow in patients with normal ventricular function.

    PubMed

    Freedman, R A; Yock, P G; Echt, D S; Popp, R L

    1986-03-01

    M-mode echocardiography and Doppler ultrasonography were used to study patterns of atrioventricular (AV) valve motion and flow in five patients with complete heart block, normal ventricular function and an implanted dual chamber pacemaker with programmable PQ intervals. Changes in AV valve motion and flow patterns resulting from steady state changes in PQ interval over the range studied (75 to 250 ms) were similar in all patients. Events reflecting AV valve opening and rapid ventricular filling bore a constant temporal relation to the Q wave and were unaffected by changes in PQ interval. Events reflecting atrial contraction occurred progressively earlier in diastole with lengthening of the PQ interval, until superimposition of atrial contraction on rapid ventricular filling at a PQ interval of 250 ms. The duration of mid-diastolic slow ventricular filling and overall diastole, defined with respect to an open valve, decreased with lengthening of the PQ interval. The onset of AV valve closure (A point) bore a constant temporal relation to the P wave, indicating that atrial systole initiated valve closure. However, completion of AV valve closure occurred progressively earlier with respect to the P wave as the PQ interval was decreased. This suggests an increasing contribution of ventricular systole to completion of AV valve closure with decreasing PQ interval. End-diastolic and end-systolic ventricular and atrial dimensions were independent of the PQ interval.

  2. Effects of coupling between sample and electrode on the electrical resistivity measurements of conductive samples

    NASA Astrophysics Data System (ADS)

    Lee, T. J.; Lee, S. K.

    2015-12-01

    A resistivity measurement system for conductive core samples has been setup using a high resolution nano-voltmeter. Using the system, in this study, various coupling effects between electrodes and the samples are discussed including contact resistance, lead resistance, temperature dependence, and heat produced within the samples by applied current. The lead resistance was over 10 times higher than the resistance of the conductive samples such as graphite or nichrome, even though the electrodes and lead lines were made of silver. Furthermore, lead resistance itself showed very strong temperature dependence, so that it is essential to subtract the lead resistance from the measured values at corresponding temperature. Minimization of contact resistance is very important, so that the axial loads are needed as big as possible unless the deformation of sample occurs.

  3. Exploring effective sampling design for monitoring soil organic carbon in degraded Tibetan grasslands.

    PubMed

    Chang, Xiaofeng; Bao, Xiaoying; Wang, Shiping; Zhu, Xiaoxue; Luo, Caiyun; Zhang, Zhenhua; Wilkes, Andreas

    2016-05-15

    The effects of climate change and human activities on grassland degradation and soil carbon stocks have become a focus of both research and policy. However, lack of research on appropriate sampling design prevents accurate assessment of soil carbon stocks and stock changes at community and regional scales. Here, we conducted an intensive survey with 1196 sampling sites over an area of 190 km(2) of degraded alpine meadow. Compared to lightly degraded meadow, soil organic carbon (SOC) stocks in moderately, heavily and extremely degraded meadow were reduced by 11.0%, 13.5% and 17.9%, respectively. Our field survey sampling design was overly intensive to estimate SOC status with a tolerable uncertainty of 10%. Power analysis showed that the optimal sampling density to achieve the desired accuracy would be 2, 3, 5 and 7 sites per 10 km(2) for lightly, moderately, heavily and extremely degraded meadows, respectively. If a subsequent paired sampling design with the optimum sample size were performed, assuming stock change rates predicted by experimental and modeling results, we estimate that about 5-10 years would be necessary to detect expected trends in SOC in the top 20 cm soil layer. Our results highlight the utility of conducting preliminary surveys to estimate the appropriate sampling density and avoid wasting resources due to over-sampling, and to estimate the sampling interval required to detect an expected sequestration rate. Future studies will be needed to evaluate spatial and temporal patterns of SOC variability.

  4. Effects of sprint interval training on VO2max and aerobic exercise performance: A systematic review and meta-analysis.

    PubMed

    Sloth, M; Sloth, D; Overgaard, K; Dalgas, U

    2013-12-01

    Recently, several studies have examined whether low-volume sprint interval training (SIT) may improve aerobic and metabolic function. The objective of this study was to systematically review the existing literature regarding the aerobic and metabolic effects of SIT in healthy sedentary or recreationally active adults. A systematic literature search was performed (Bibliotek.dk, SPORTDiscus, Embase, PEDro, SveMed+, and Pubmed). Meta-analytical procedures were applied evaluating effects on maximal oxygen consumption (VO2max). Nineteen unique studies [four randomized controlled trials (RCTs), nine matched-controlled trials and six noncontrolled studies] were identified, evaluating SIT interventions lasting 2-8 weeks. Strong evidence support improvements of aerobic exercise performance and VO2max following SIT. A meta-analysis across 13 studies evaluating effects of SIT on VO2max showed a weighted mean effects size of g = 0.63 95% CI (0.39; 0.87) and VO2max increases of 4.2-13.4%. Solid evidence support peripheral adaptations known to increase the oxidative potential of the muscle following SIT, whereas evidence regarding central adaptations was limited and equivocal. Some evidence indicated changes in substrate oxidation at rest and during exercise as well as improved glycemic control and insulin sensitivity following SIT. In conclusion, strong evidence support improvement of aerobic exercise performance and VO2max following SIT, which coincides with peripheral muscular adaptations. Future RCTs on long-term SIT and underlying mechanisms are warranted.

  5. Effect of different post-feeding intervals on the total time of development of the blowfly Lucilia sericata (Diptera: Calliphoridae).

    PubMed

    Mai, Madeleine; Amendt, Jens

    2012-09-10

    By estimating the age of the immature stages of flies developing on a corpse, forensic entomologists are able to establish the minimum post-mortem interval. Blowflies, which are the first and most important colonizers, usually leave the cadaver at the end of the last larval stage searching for a pupation site. This period of development is referred as the post-feeding or wandering stage. The characteristics of the ground where the corpse was placed might be of notable importance for the post-feeding dispersal time: For pupariation the larvae prefer an environment protected from light and predators and may have a longer dispersal time in order to reach an appropriate pupation site. Hence, the dispersal time can vary and may influence the total time of development which may lead to an erroneous calculation of the post-mortem interval. This study investigates the effect of various post-feeding time intervals on the development of the blowfly Lucilia sericata at a temperature of 25°C. As larvae reached the post-feeding stage a pupariation substrate was offered at 0 and after 12, 24 and 48h. Only the larvae with a dispersal time of 24h (total time of development 325.2h; median) and 48h (total time of development 347.7h; median) showed a significantly longer total development time compared to the control group (total time of development 318.4h; median). The mortality rate did not differ between groups; however the flies that emerged from the group with a dispersal of 48h were significantly smaller indicating increased energy consumption during dispersal. The results of this study indicate that a prolonged post-feeding stage could increase the total developmental time of L. sericata which should be taken into consideration when interpreting entomological findings. The need for a serious examination of current rearing practices in forensic entomology laboratories is indicated because reference data sets for the time of development are usually produced by offering the post

  6. Effect of different post-feeding intervals on the total time of development of the blowfly Lucilia sericata (Diptera: Calliphoridae).

    PubMed

    Mai, Madeleine; Amendt, Jens

    2012-09-10

    By estimating the age of the immature stages of flies developing on a corpse, forensic entomologists are able to establish the minimum post-mortem interval. Blowflies, which are the first and most important colonizers, usually leave the cadaver at the end of the last larval stage searching for a pupation site. This period of development is referred as the post-feeding or wandering stage. The characteristics of the ground where the corpse was placed might be of notable importance for the post-feeding dispersal time: For pupariation the larvae prefer an environment protected from light and predators and may have a longer dispersal time in order to reach an appropriate pupation site. Hence, the dispersal time can vary and may influence the total time of development which may lead to an erroneous calculation of the post-mortem interval. This study investigates the effect of various post-feeding time intervals on the development of the blowfly Lucilia sericata at a temperature of 25°C. As larvae reached the post-feeding stage a pupariation substrate was offered at 0 and after 12, 24 and 48h. Only the larvae with a dispersal time of 24h (total time of development 325.2h; median) and 48h (total time of development 347.7h; median) showed a significantly longer total development time compared to the control group (total time of development 318.4h; median). The mortality rate did not differ between groups; however the flies that emerged from the group with a dispersal of 48h were significantly smaller indicating increased energy consumption during dispersal. The results of this study indicate that a prolonged post-feeding stage could increase the total developmental time of L. sericata which should be taken into consideration when interpreting entomological findings. The need for a serious examination of current rearing practices in forensic entomology laboratories is indicated because reference data sets for the time of development are usually produced by offering the post

  7. Effects of Novel Supramaximal Interval Training Versus Continuous Training on Performance in Preconditioned Collegiate, National, and International Class Rowers.

    PubMed

    Richer, Sylvie D; Nolte, Volker W; Bechard, Dan J; Belfry, Glen R

    2016-06-01

    Richer, SD, Nolte, VW, Bechard, DJ, and Belfry, GR. Effects of novel supramaximal interval training versus continuous training on performance in preconditioned collegiate, national, and international class rowers. J Strength Cond Res 30(6): 1752-1762, 2016-This investigation compared supramaximal oxygen uptake interval training with continuous training in collegiate, national, and international class rowers. It was hypothesized that 6 supramaximal intensity sessions over 11 days would increase power on selected power measures. After 8 weeks of training for a new season, 10 heavyweight and 6 lightweight rowers were randomized into 2 groups. A ramp test to limit of tolerance to determine peak aerobic power (6 females: 25 W·min; 10 males: 30 W·min) and an all-out 3-minute test to determine peak power, 60-second power, critical power, and work above critical power (W') were performed before and after training. A supramaximal training session consisted of 10 cycles of 10-second work (140% peak aerobic power):5-second recovery followed by 8 minutes of active recovery, and repeated 6 times. The continuous group performed predominantly moderate intensity (below lactate threshold) training. All training was performed on rowing ergometers. Critical power increased pre-to-post supramaximal (Δ7%) and continuous training (Δ9%), respectively (336 ± 59W to 360 ± 59W; 290 ± 73W to 316 ± 74W; p ≤ 0.05), whereas the mean power output from all performance measures increased only after supramaximal training (Δ7%) (464 ± 158W to 496 ± 184W; p ≤ 0.05). Testing also revealed decreased W' (Δ21%) and 60-second power (Δ4%) pre-to-post continuous training only (p ≤ 0.05). No differences (p > 0.05) in peak aerobic power or peak power were observed pre-to-post training in either group. In conclusion, after an 8-week preconditioning period, supramaximal interval training preserved anaerobic capacity compared with predominantly continuous training and elicited similar

  8. The Effect of Green Tea Ingestion and Interval Sprinting Exercise on the Body Composition of Overweight Males: A Randomized Trial

    PubMed Central

    Gahreman, Daniel; Heydari, Mehrdad; Boutcher, Yati; Freund, Judith; Boutcher, Stephen

    2016-01-01

    The combined effect of green tea ingestion and interval sprinting exercise on body and abdominal fat of overweight males was investigated. Participants were randomly assigned into control (C), green tea (GT), interval sprinting exercise (ISE), and green tea and ISE (GT + ISE) groups. The GT, GT + ISE, and C groups consumed three GT capsules daily. The ISE and GT + ISE groups completed 36 ISE sessions over 12 weeks. Forty eight overweight males with a mean BMI of 28.5 ± 0.92 kg/m2 and age of 26 ± 0.7 years acted as participants. There was a significant reduction in total and abdominal fat mass for the ISE and GT + ISE groups, p < 0.05, however, total and abdominal fat mass did not significantly change in the GT and C groups. There was a significant increase in total lean mass, p < 0.05, after the intervention for the ISE and GT + ISE groups only. There was a significant increase in fat oxidation during submaximal aerobic exercise, p < 0.05, after the intervention for the ISE, GT + ISE, and GT groups with no change for the C group. Following the 12-week intervention the ISE and GT + ISE groups, compared to C, recorded a significantly greater decrease in body and abdominal fat, and a significant increase in total lean mass. Ingestion of green tea by itself, however, did not result in a significant decrease in body or abdominal fat, but increased fat utilization during submaximal exercise. The combination of 12 weeks of GT ingestion and ISE did not result in greater total and abdominal fat reduction compared to 12 weeks of ISE alone. PMID:27548216

  9. The Effect of Green Tea Ingestion and Interval Sprinting Exercise on the Body Composition of Overweight Males: A Randomized Trial.

    PubMed

    Gahreman, Daniel; Heydari, Mehrdad; Boutcher, Yati; Freund, Judith; Boutcher, Stephen

    2016-01-01

    The combined effect of green tea ingestion and interval sprinting exercise on body and abdominal fat of overweight males was investigated. Participants were randomly assigned into control (C), green tea (GT), interval sprinting exercise (ISE), and green tea and ISE (GT + ISE) groups. The GT, GT + ISE, and C groups consumed three GT capsules daily. The ISE and GT + ISE groups completed 36 ISE sessions over 12 weeks. Forty eight overweight males with a mean BMI of 28.5 ± 0.92 kg/m² and age of 26 ± 0.7 years acted as participants. There was a significant reduction in total and abdominal fat mass for the ISE and GT + ISE groups, p < 0.05, however, total and abdominal fat mass did not significantly change in the GT and C groups. There was a significant increase in total lean mass, p < 0.05, after the intervention for the ISE and GT + ISE groups only. There was a significant increase in fat oxidation during submaximal aerobic exercise, p < 0.05, after the intervention for the ISE, GT + ISE, and GT groups with no change for the C group. Following the 12-week intervention the ISE and GT + ISE groups, compared to C, recorded a significantly greater decrease in body and abdominal fat, and a significant increase in total lean mass. Ingestion of green tea by itself, however, did not result in a significant decrease in body or abdominal fat, but increased fat utilization during submaximal exercise. The combination of 12 weeks of GT ingestion and ISE did not result in greater total and abdominal fat reduction compared to 12 weeks of ISE alone. PMID:27548216

  10. The Effect of Green Tea Ingestion and Interval Sprinting Exercise on the Body Composition of Overweight Males: A Randomized Trial.

    PubMed

    Gahreman, Daniel; Heydari, Mehrdad; Boutcher, Yati; Freund, Judith; Boutcher, Stephen

    2016-08-19

    The combined effect of green tea ingestion and interval sprinting exercise on body and abdominal fat of overweight males was investigated. Participants were randomly assigned into control (C), green tea (GT), interval sprinting exercise (ISE), and green tea and ISE (GT + ISE) groups. The GT, GT + ISE, and C groups consumed three GT capsules daily. The ISE and GT + ISE groups completed 36 ISE sessions over 12 weeks. Forty eight overweight males with a mean BMI of 28.5 ± 0.92 kg/m² and age of 26 ± 0.7 years acted as participants. There was a significant reduction in total and abdominal fat mass for the ISE and GT + ISE groups, p < 0.05, however, total and abdominal fat mass did not significantly change in the GT and C groups. There was a significant increase in total lean mass, p < 0.05, after the intervention for the ISE and GT + ISE groups only. There was a significant increase in fat oxidation during submaximal aerobic exercise, p < 0.05, after the intervention for the ISE, GT + ISE, and GT groups with no change for the C group. Following the 12-week intervention the ISE and GT + ISE groups, compared to C, recorded a significantly greater decrease in body and abdominal fat, and a significant increase in total lean mass. Ingestion of green tea by itself, however, did not result in a significant decrease in body or abdominal fat, but increased fat utilization during submaximal exercise. The combination of 12 weeks of GT ingestion and ISE did not result in greater total and abdominal fat reduction compared to 12 weeks of ISE alone.

  11. Sub-Nyquist artefacts and sampling moiré effects

    PubMed Central

    Amidror, Isaac

    2015-01-01

    Sampling moiré effects are well known in signal processing. They occur when a continuous periodic signal g(x) is sampled using a sampling frequency fs that does not respect the Nyquist condition, and the signal-frequency f folds over and gives a new, false low frequency in the sampled signal. However, some visible beating artefacts may also occur in the sampled signal when g(x) is sampled using a sampling frequency fs which fully respects the Nyquist condition. We call these phenomena sub-Nyquist artefacts. Although these beating effects have already been reported in the literature, their detailed mathematical behaviour is not widely known. In this paper, we study the behaviour of these phenomena and compare it with analogous results from the moiré theory. We show that both sampling moirés and sub-Nyquist artefacts obey the same basic mathematical rules, in spite of the differences between them. This leads us to a unified approach that explains all of these phenomena and puts them under the same roof. In particular, it turns out that all of these phenomena occur when the signal-frequency f and the sampling frequency fs satisfy f≈(m/n)fs with integer m, n, where m/n is a reduced integer ratio; cases with n=1 correspond to true sampling moiré effects. PMID:26064621

  12. Sub-Nyquist artefacts and sampling moiré effects.

    PubMed

    Amidror, Isaac

    2015-03-01

    Sampling moiré effects are well known in signal processing. They occur when a continuous periodic signal g(x) is sampled using a sampling frequency f s that does not respect the Nyquist condition, and the signal-frequency f folds over and gives a new, false low frequency in the sampled signal. However, some visible beating artefacts may also occur in the sampled signal when g(x) is sampled using a sampling frequency f s which fully respects the Nyquist condition. We call these phenomena sub-Nyquist artefacts. Although these beating effects have already been reported in the literature, their detailed mathematical behaviour is not widely known. In this paper, we study the behaviour of these phenomena and compare it with analogous results from the moiré theory. We show that both sampling moirés and sub-Nyquist artefacts obey the same basic mathematical rules, in spite of the differences between them. This leads us to a unified approach that explains all of these phenomena and puts them under the same roof. In particular, it turns out that all of these phenomena occur when the signal-frequency f and the sampling frequency f s satisfy f≈(m/n)f s with integer m, n, where m/n is a reduced integer ratio; cases with n=1 correspond to true sampling moiré effects.

  13. The Effect of Retention Interval Task Difficulty on Young Children's Prospective Memory: Testing the Intention Monitoring Hypothesis

    ERIC Educational Resources Information Center

    Mahy, Caitlin E. V.; Moses, Louis J.

    2015-01-01

    The current study examined the impact of retention interval task difficulty on 4- and 5-year-olds' prospective memory (PM) to test the hypothesis that children periodically monitor their intentions during the retention interval and that disrupting this monitoring may result in poorer PM performance. In addition, relations among PM, working memory,…

  14. Methods of human body odor sampling: the effect of freezing.

    PubMed

    Lenochova, Pavlina; Roberts, S Craig; Havlicek, Jan

    2009-02-01

    Body odor sampling is an essential tool in human chemical ecology research. However, methodologies of individual studies vary widely in terms of sampling material, length of sampling, and sample processing. Although these differences might have a critical impact on results obtained, almost no studies test validity of current methods. Here, we focused on the effect of freezing samples between collection and use in experiments involving body odor perception. In 2 experiments, we tested whether axillary odors were perceived differently by raters when presented fresh or having been frozen and whether several freeze-thaw cycles affected sample quality. In the first experiment, samples were frozen for 2 weeks, 1 month, or 4 months. We found no differences in ratings of pleasantness, attractiveness, or masculinity between fresh and frozen samples. Similarly, almost no differences between repeatedly thawed and fresh samples were found. We found some variations in intensity; however, this was unrelated to length of storage. The second experiment tested differences between fresh samples and those frozen for 6 months. Again no differences in subjective ratings were observed. These results suggest that freezing has no significant effect on perceived odor hedonicity and that samples can be reliably used after storage for relatively long periods.

  15. Effects of sample size and sampling frequency on studies of brown bear home ranges and habitat use

    USGS Publications Warehouse

    Arthur, Steve M.; Schwartz, Charles C.

    1999-01-01

    We equipped 9 brown bears (Ursus arctos) on the Kenai Peninsula, Alaska, with collars containing both conventional very-high-frequency (VHF) transmitters and global positioning system (GPS) receivers programmed to determine an animal's position at 5.75-hr intervals. We calculated minimum convex polygon (MCP) and fixed and adaptive kernel home ranges for randomly-selected subsets of the GPS data to examine the effects of sample size on accuracy and precision of home range estimates. We also compared results obtained by weekly aerial radiotracking versus more frequent GPS locations to test for biases in conventional radiotracking data. Home ranges based on the MCP were 20-606 km2 (x = 201) for aerial radiotracking data (n = 12-16 locations/bear) and 116-1,505 km2 (x = 522) for the complete GPS data sets (n = 245-466 locations/bear). Fixed kernel home ranges were 34-955 km2 (x = 224) for radiotracking data and 16-130 km2 (x = 60) for the GPS data. Differences between means for radiotracking and GPS data were due primarily to the larger samples provided by the GPS data. Means did not differ between radiotracking data and equivalent-sized subsets of GPS data (P > 0.10). For the MCP, home range area increased and variability decreased asymptotically with number of locations. For the kernel models, both area and variability decreased with increasing sample size. Simulations suggested that the MCP and kernel models required >60 and >80 locations, respectively, for estimates to be both accurate (change in area <1%/additional location) and precise (CV < 50%). Although the radiotracking data appeared unbiased, except for the relationship between area and sample size, these data failed to indicate some areas that likely were important to bears. Our results suggest that the usefulness of conventional radiotracking data may be limited by potential biases and variability due to small samples. Investigators that use home range estimates in statistical tests should consider the

  16. Effects of response strategy and retention interval on performance of Clark's nutcrackers in a radial maze analogue.

    PubMed

    Olson, D J; Kamil, A C; Balda, R P

    1993-04-01

    Two groups of Clark's nutcrackers (Nucifraga columbiana) were trained to use either a stay or shift response strategy in a radial maze analogue. Each trial had a preretention stage, a retention interval, and a postretention test. In Experiment 1, acquisition with a 5-min retention interval was studied. Response strategy did not affect the rate at which the task was learned. Performance following longer retention intervals was tested in Experiments 2-4. Changes in retention intervals were presented in trial blocks of increasing duration in Experiment 2 and were randomly presented between trials in Experiment 3. Experiment 4 extended the retention interval to 24 hr. No difference in performance was found between the 2 groups in any of these experiments. These results suggest a flexible relationship between spatial memory and response requirement in food-hoarding birds for at least 1 spatial memory task.

  17. The effect of parturition induction treatment on interval to calving, calving ease, postpartum uterine health, and resumption of ovarian cyclicity in beef heifers.

    PubMed

    Šavc, Miha; Kenny, David A; Beltman, Marijke E

    2016-05-01

    The aim of this study was to compare the effects of two parturition induction protocols with a nontreated control group, on interval to calving, calving ease, postpartum uterine health, and ovarian cyclicity in beef heifers. At Day 285 of gestation, 81 crossbred recipient beef heifers carrying purebred Simmental fetuses, were blocked by live-weight, body condition score, expected calving date and fetal sex, and assigned to one of three groups: (1) control (CON; no induction treatment, n = 29); (2) induction with corticosteroids (CORT; n = 27); or (3) induction with corticosteroids plus prostaglandin (CORT + PG; n = 25). Interval from induction to calving in hours and calving ease on a scale of 1 to 5 were recorded. Vaginal mucus samples were collected on Day 21 and Day 42 after calving (Day 0) by means of a Metricheck and scored on a scale of 0 to 3. Reproductive tract examinations were conducted on Day 21 and Day 42 after calving, and uterine cytology samples were obtained on Day 21. A positive cytologic sample was defined as greater than 18% neutrophils in the sample obtained via a cytobrush technique. Cows were considered to have resumed ovarian cyclicity if the presence of the CL was confirmed. Data were analyzed using the Mixed (normally distributed data) and Genmod (nonparametric data) procedures of SAS (v. 9.3). The interval from treatment to calving was longer (P < 0.0001) for CON (161.9 ± 15.12 hours) animals compared with CORT (39.7 ± 11.64 hours) or CORT + PG (32.6 ± 12.10 hours), which did not differ. Treatment did not affect calving difficulty score. There was also no difference in incidence of retained placenta between the three groups. At Day 21 postpartum, cytology score tended to be higher for both induced groups (48%) compared with the control animals (24%), but this was not the case for vaginal mucus score (CON 52%, CORT 70%, and CORT + PG 52%). A higher proportion of CON had an involuted uterus by Day 21 postpartum (69

  18. Approximate Confidence Intervals for Moment-Based Estimators of the Between-Study Variance in Random Effects Meta-Analysis

    ERIC Educational Resources Information Center

    Jackson, Dan; Bowden, Jack; Baker, Rose

    2015-01-01

    Moment-based estimators of the between-study variance are very popular when performing random effects meta-analyses. This type of estimation has many advantages including computational and conceptual simplicity. Furthermore, by using these estimators in large samples, valid meta-analyses can be performed without the assumption that the treatment…

  19. Effects of spectrometer band pass, sampling, and signal-to-noise ratio on spectral identification using the Tetracorder algorithm

    USGS Publications Warehouse

    Swayze, G.A.; Clark, R.N.; Goetz, A.F.H.; Chrien, T.H.; Gorelick, N.S.

    2003-01-01

    Estimates of spectrometer band pass, sampling interval, and signal-to-noise ratio required for identification of pure minerals and plants were derived using reflectance spectra convolved to AVIRIS, HYDICE, MIVIS, VIMS, and other imaging spectrometers. For each spectral simulation, various levels of random noise were added to the reflectance spectra after convolution, and then each was analyzed with the Tetracorder spectra identification algorithm [Clark et al., 2003]. The outcome of each identification attempt was tabulated to provide an estimate of the signal-to-noise ratio at which a given percentage of the noisy spectra were identified correctly. Results show that spectral identification is most sensitive to the signal-to-noise ratio at narrow sampling interval values but is more sensitive to the sampling interval itself at broad sampling interval values because of spectral aliasing, a condition when absorption features of different materials can resemble one another. The band pass is less critical to spectral identification than the sampling interval or signal-to-noise ratio because broadening the band pass does not induce spectral aliasing. These conclusions are empirically corroborated by analysis of mineral maps of AVIRIS data collected at Cuprite, Nevada, between 1990 and 1995, a period during which the sensor signal-to-noise ratio increased up to sixfold. There are values of spectrometer sampling and band pass beyond which spectral identification of materials will require an abrupt increase in sensor signal-to-noise ratio due to the effects of spectral aliasing. Factors that control this threshold are the uniqueness of a material's diagnostic absorptions in terms of shape and wavelength isolation, and the spectral diversity of the materials found in nature and in the spectral library used for comparison. Array spectrometers provide the best data for identification when they critically sample spectra. The sampling interval should not be broadened to

  20. Sampling Scarab Beetles in Tropical Forests: The Effect of Light Source and Night Sampling Periods

    PubMed Central

    García-López, Alejandra; Micó, Estefanía; Zumbado, Manuel A.; Galante, Eduardo

    2011-01-01

    Light traps have been used widely to sample insect abundance and diversity, but their performance for sampling scarab beetles in tropical forests based on light source type and sampling hours throughout the night has not been evaluated. The efficiency of mercury-vapour lamps, cool white light and ultraviolet light sources in attracting Dynastinae, Melolonthinae and Rutelinae scarab beetles, and the most adequate period of the night to carry out the sampling was tested in different forest areas of Costa Rica. Our results showed that light source wavelengths and hours of sampling influenced scarab beetle catches. No significant differences were observed in trap performance between the ultraviolet light and mercury-vapour traps, whereas these two methods caught significantly more species richness and abundance than cool white light traps. Species composition also varied between methods. Large differences appear between catches in the sampling period, with the first five hours of the night being more effective than the last five hours. Because of their high efficiency and logistic advantages, we recommend ultraviolet light traps deployed during the first hours of the night as the best sampling method for biodiversity studies of those scarab beetles in tropical forests. PMID:22208730

  1. Effect of Sample Storage Temperature and Time Delay on Blood Gases, Bicarbonate and pH in Human Arterial Blood Samples

    PubMed Central

    Mohammadhoseini, Elham; Safavi, Enayat; Seifi, Sepideh; Seifirad, Soroush; Firoozbakhsh, Shahram; Peiman, Soheil

    2015-01-01

    Background: Results of arterial blood gas analysis can be biased by pre-analytical factors, such as time interval before analysis, temperature during storage and syringe type. Objectives: To investigate the effects of samples storage temperature and time delay on blood gases, bicarbonate and PH results in human arterial blood samples. Patients and Methods: 2.5 mL arterial blood samples were drawn from 45 patients via an indwelling Intraarterial catheter. Each sample was divided into five equal samples and stored in multipurpose tuberculin plastic syringes. Blood gas analysis was performed on one of five samples as soon as possible. Four other samples were divided into two groups stored at 22°C and 0°C. Blood gas analyses were repeated at 30 and 60 minutes after sampling. Results: PaO2 of the samples stored at 0°C was increased significantly after 60 minutes (P = 0.007). The PaCO2 of the samples kept for 30 and 60 minutes at 22°C was significantly higher than primary result (P = 0.04, P < 0.001). In samples stored at 22°C, pH decreased significantly after 30 and 60 minutes (P = 0.017, P = 0.001). There were no significant differences in other results of samples stored at 0°C or 22°C after 30 or 60 minutes. Conclusions: In samples stored in plastic syringes, overestimation of PaO2 levels should be noted if samples cooled before analysis. In samples stored in plastic syringes, it is not necessary to store samples in iced water when analysis delayed up to one hour. PMID:26019892

  2. Emergence of anti-conflict effects of zolpidem in rhesus monkeys following extended post-injection intervals

    PubMed Central

    Rowlett, James K.; Kehne, John H.; Sprenger, Ken J.; Maynard, George D.

    2010-01-01

    Rationale Zolpidem is a hypnotic drug that binds to γ-aminobutyric acid type A (GABAA) receptors but lacks consistently demonstrable anxiolytic efficacy. Methods Rhesus monkeys (N=4) were trained under a multiple schedule in which food-maintained responding was programmed (18-response, fixed ratio) for a 5-min period, followed by a 5-min period in which the food-maintained responding was suppressed by response-contingent electric shock (20-response fixed ratio). Doses of zolpidem (range= 0.03 to 1.0 mg/kg, i.v.) were administered 5 minutes before the session and responding was re-assessed at 3 additional 20 minute intervals. A similar experiment also was carried out with the non-selective benzodiazepine, triazolam, over a dose range of 0.001 to 0.1 mg/kg, i.v. Results Zolpidem did not engender a significant increase in average rates of suppressed responding at earlier time points; however, rates of non-suppressed responding were robustly decreased. At 45- and 65-min post-injection, zolpidem treatment resulted in a dose-dependent increase in rates of suppressed responding. In contrast, the non-selective benzodiazepine triazolam increased rates of suppressed responding in a dose-dependent manner at all 4 time points, although decreases in non-suppressed responding were less at the later time points. Conclusions These findings suggest that zolpidem has anxiolytic-like effects, but only >25 min after i.v. injection in this rhesus monkey conflict model. It was hypothesized that time-dependent effects on the response rate suppressing properties of zolpidem become tolerant (i.e., acute tolerance). Because anxiolytic-like effects remain stable throughout the session, the absence of rate-decreasing effects may “unmask” anti-conflict effects. PMID:21103864

  3. Effects of inter-trial interval length on food-hoarding partial reinforcement of running behaviour in the golden hamster.

    PubMed

    Launay, M; Blancheteau, M

    1982-12-01

    Food-hoarding provides an adequate motivation in sated hamsters for the acquisition of a two-way running response. This learning was studied using a discrete-trial procedure, in continuous (CR) and partial reinforcement (PR) conditions, with two different inter-trial interval (ITI) lengths. The dependent variables were: the time spent by Ss in the goal section of the runway, and the number of their runs during extinction. The PR training had two effects on goal times: a slow decrease in acquisition on non-reinforced trials, and then a stabilization at this level during the extinction phase, as contrasted with the sudden increase found in CR-trained Ss when they were switched from acquisition to extinction conditions. However, the PR effects on number of runs depended upon ITI length: resistance to extinction of PR-trained Ss was superior to that of CR-trained Ss with spaced, but not with massed, trials. In the latter case, CR-trained Ss persisted as much as did PR-trained Ss. An hypothesis is offered, along the lines of the Frustration theory.

  4. The Effects of Sprint Interval vs. Continuous Endurance Training on Physiological And Metabolic Adaptations in Young Healthy Adults

    PubMed Central

    Nalcakan, Gulbin Rudarli

    2014-01-01

    The purpose of this study was to compare the effects of sprint interval training (SIT) and continuous endurance training (CET) on selected anthropometric, aerobic, and anaerobic performance indices as well as the blood lipid profile, inflammatory and muscle damage markers in healthy young males. Fifteen recreationally active male volunteers (age: 21.7 ±2.2 years, body mass: 83.0 ±8.0 kg, body height: 1.82 ±0.05 m) were divided into two groups according to their initial VO2max levels. Training programs were conducted 3 times per week for 7 weeks. The SIT program consisted of 4–6 Wingate anaerobic sprints with a 4.5 min recovery, while CET consisted of 30–50 min cycling at 60% VO2max. Biochemical, anthropometric and fitness assessments were performed both pre and post-intervention. Significant improvements in VO2max, anaerobic power and capacity, and VO2 utilization during the submaximal workout and significant decreases in body fat and in waist circumference after the intervention occurred in both SIT and CET groups. Significantly greater gross efficiency was measured in the CET group. No differences in the lipid profile or serum levels of inflammatory, myocardial and skeletal muscle damage markers were observed after the training period. The study results agree with the effectiveness of a 30 s all-out training program with a reduced time commitment for anthropometric, aerobic and anaerobic adaptation and eliminate doubts about its safety as a model. PMID:25713670

  5. Effects of Small-Sided Games vs. Interval Training in Aerobic Fitness and Physical Enjoyment in Young Elite Soccer Players

    PubMed Central

    Martín, Juan; Lerga, Javier; Sánchez, Felipe; Villagra, Federico; Zulueta, Javier J.

    2015-01-01

    The purpose of this study was to compare the effects of Small-Sided Games (SSG) vs. Interval Training (IT) in soccer training on aerobic fitness and physical enjoyment in youth elite soccer players during the last 8 weeks of the season. Seventeen U-16 male soccer players (age = 15.5 ± 0.6 years, and 8.5 years of experience) of a Spanish First Division club academy were randomized to 2 different groups for 6 weeks: SSG group (n = 9) and IT group (n = 8). In addition to the usual technical and tactical sessions and competitive games, the SSG group performed 11 sessions with different SSGs, whereas the IT group performed the same number of sessions of IT. Players were tested before and after the 6-week training intervention with a continuous maximal multistage running field test and the counter movement jump test (CMJ). At the end of the study, players answered the physical activity enjoyment scale (PACES). During the study, heart rate (HR) and session perceived effort (sRPE) were assessed. SSGs were as effective as IT in maintaining the aerobic fitness in elite young soccer players during the last weeks of the season. Players in the SSG group declared a greater physical enjoyment than IT (P = 0.006; ES = 1.86 ± 1.07). Coaches could use SSG training during the last weeks of the season as an option without fear of losing aerobic fitness while promoting high physical enjoyment. PMID:26331623

  6. The Effects of Sprint Interval vs. Continuous Endurance Training on Physiological And Metabolic Adaptations in Young Healthy Adults.

    PubMed

    Nalcakan, Gulbin Rudarli

    2014-12-01

    The purpose of this study was to compare the effects of sprint interval training (SIT) and continuous endurance training (CET) on selected anthropometric, aerobic, and anaerobic performance indices as well as the blood lipid profile, inflammatory and muscle damage markers in healthy young males. Fifteen recreationally active male volunteers (age: 21.7 ±2.2 years, body mass: 83.0 ±8.0 kg, body height: 1.82 ±0.05 m) were divided into two groups according to their initial VO2max levels. Training programs were conducted 3 times per week for 7 weeks. The SIT program consisted of 4-6 Wingate anaerobic sprints with a 4.5 min recovery, while CET consisted of 30-50 min cycling at 60% VO2max. Biochemical, anthropometric and fitness assessments were performed both pre and post-intervention. Significant improvements in VO2max, anaerobic power and capacity, and VO2 utilization during the submaximal workout and significant decreases in body fat and in waist circumference after the intervention occurred in both SIT and CET groups. Significantly greater gross efficiency was measured in the CET group. No differences in the lipid profile or serum levels of inflammatory, myocardial and skeletal muscle damage markers were observed after the training period. The study results agree with the effectiveness of a 30 s all-out training program with a reduced time commitment for anthropometric, aerobic and anaerobic adaptation and eliminate doubts about its safety as a model.

  7. Effects of Small-Sided Games vs. Interval Training in Aerobic Fitness and Physical Enjoyment in Young Elite Soccer Players.

    PubMed

    Los Arcos, Asier; Vázquez, Juan Sebastián; Martín, Juan; Lerga, Javier; Sánchez, Felipe; Villagra, Federico; Zulueta, Javier J

    2015-01-01

    The purpose of this study was to compare the effects of Small-Sided Games (SSG) vs. Interval Training (IT) in soccer training on aerobic fitness and physical enjoyment in youth elite soccer players during the last 8 weeks of the season. Seventeen U-16 male soccer players (age = 15.5 ± 0.6 years, and 8.5 years of experience) of a Spanish First Division club academy were randomized to 2 different groups for 6 weeks: SSG group (n = 9) and IT group (n = 8). In addition to the usual technical and tactical sessions and competitive games, the SSG group performed 11 sessions with different SSGs, whereas the IT group performed the same number of sessions of IT. Players were tested before and after the 6-week training intervention with a continuous maximal multistage running field test and the counter movement jump test (CMJ). At the end of the study, players answered the physical activity enjoyment scale (PACES). During the study, heart rate (HR) and session perceived effort (sRPE) were assessed. SSGs were as effective as IT in maintaining the aerobic fitness in elite young soccer players during the last weeks of the season. Players in the SSG group declared a greater physical enjoyment than IT (P = 0.006; ES = 1.86 ± 1.07). Coaches could use SSG training during the last weeks of the season as an option without fear of losing aerobic fitness while promoting high physical enjoyment. PMID:26331623

  8. Performance of Random Effects Model Estimators under Complex Sampling Designs

    ERIC Educational Resources Information Center

    Jia, Yue; Stokes, Lynne; Harris, Ian; Wang, Yan

    2011-01-01

    In this article, we consider estimation of parameters of random effects models from samples collected via complex multistage designs. Incorporation of sampling weights is one way to reduce estimation bias due to unequal probabilities of selection. Several weighting methods have been proposed in the literature for estimating the parameters of…

  9. The Effect of Sample Size on Latent Growth Models.

    ERIC Educational Resources Information Center

    Hamilton, Jennifer; Gagne, Phillip E.; Hancock, Gregory R.

    A Monte Carlo simulation approach was taken to investigate the effect of sample size on a variety of latent growth models. A fully balanced experimental design was implemented, with samples drawn from multivariate normal populations specified to represent 12 unique growth models. The models varied factorially by crossing number of time points,…

  10. Effective sampling range for protein-based lures

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Effective sampling range is defined as the maximum distance from which an insect can reach an attractive source in a given period of time. Information on sampling range is valuable for determining appropriate coverage of traps for use in population delimitation, mass trapping control strategies, or...

  11. An interval model updating strategy using interval response surface models

    NASA Astrophysics Data System (ADS)

    Fang, Sheng-En; Zhang, Qiu-Hu; Ren, Wei-Xin

    2015-08-01

    Stochastic model updating provides an effective way of handling uncertainties existing in real-world structures. In general, probabilistic theories, fuzzy mathematics or interval analyses are involved in the solution of inverse problems. However in practice, probability distributions or membership functions of structural parameters are often unavailable due to insufficient information of a structure. At this moment an interval model updating procedure shows its superiority in the aspect of problem simplification since only the upper and lower bounds of parameters and responses are sought. To this end, this study develops a new concept of interval response surface models for the purpose of efficiently implementing the interval model updating procedure. The frequent interval overestimation due to the use of interval arithmetic can be maximally avoided leading to accurate estimation of parameter intervals. Meanwhile, the establishment of an interval inverse problem is highly simplified, accompanied by a saving of computational costs. By this means a relatively simple and cost-efficient interval updating process can be achieved. Lastly, the feasibility and reliability of the developed method have been verified against a numerical mass-spring system and also against a set of experimentally tested steel plates.

  12. Cardiorespiratory Effects of One-Legged High-Intensity Interval Training in Normoxia and Hypoxia: A Pilot Study.

    PubMed

    Menz, Verena; Semsch, Mona; Mosbach, Florian; Burtscher, Martin

    2016-06-01

    A higher-than-average maximal oxygen consumption (VO2max), is closely associated with decreased morbidity and mortality and improved quality of life and acts as a marker of cardiorespiratory fitness. Although there is no consensus about an optimal training method to enhance VO2max, nevertheless training of small muscle groups and repeated exposure to hypoxia seem to be promising approaches. Therefore, this study was aimed at gaining innovative insights into the effects of small muscle group training in normoxia and hypoxia. Thirteen healthy participants were randomly assigned to the hypoxic (HG, n = 7) or normoxic (NG, n = 6) training group. Both groups completed nine high-intensity interval training sessions in 3 wks. The NG performed the training in normoxia (FiO2: 0.21; ~ 600 m) and the HG in hypoxia (FiO2: 0.126; ~ 4500 m). Each session consisted of 4 x 4 min one-legged cycling at 90% of maximal heart rate separated by 4 min recovery periods. Before and after the intervention period, VO2max and peak power output (Wmax) and responses to submaximal cycling (100 and 150 watts) were assessed in a laboratory cycling test. Peak power output significantly improved within both groups (9.6 ± 4.8% and 12.6 ± 8.9% for HG and NG, respectively) with no significant interaction (p = 0.277). However, VO2max only significantly increased after training in hypoxia from 45.4 ± 10.1 to 50.0 ± 9.8 ml/min/kg (10.8 ± 6.0%; p = 0.002) with no significant interaction (p = 0.146). The maximal O2-pulse improved within the HG and demonstrated a significant interaction (p = 0.040). One-legged cycling training significantly improved VO2max and peak power output. Training under hypoxic conditions may generate greater effects on VO2max than a similar training in normoxia and is considered as a promising training method for improving cardiorespiratory fitness. Key pointsNine sessions of one-legged high-intensity interval training significantly improved physical fitness.One-legged hypoxic

  13. Cardiorespiratory Effects of One-Legged High-Intensity Interval Training in Normoxia and Hypoxia: A Pilot Study

    PubMed Central

    Menz, Verena; Semsch, Mona; Mosbach, Florian; Burtscher, Martin

    2016-01-01

    A higher-than-average maximal oxygen consumption (VO2max), is closely associated with decreased morbidity and mortality and improved quality of life and acts as a marker of cardiorespiratory fitness. Although there is no consensus about an optimal training method to enhance VO2max, nevertheless training of small muscle groups and repeated exposure to hypoxia seem to be promising approaches. Therefore, this study was aimed at gaining innovative insights into the effects of small muscle group training in normoxia and hypoxia. Thirteen healthy participants were randomly assigned to the hypoxic (HG, n = 7) or normoxic (NG, n = 6) training group. Both groups completed nine high-intensity interval training sessions in 3 wks. The NG performed the training in normoxia (FiO2: 0.21; ~ 600 m) and the HG in hypoxia (FiO2: 0.126; ~ 4500 m). Each session consisted of 4 x 4 min one-legged cycling at 90% of maximal heart rate separated by 4 min recovery periods. Before and after the intervention period, VO2max and peak power output (Wmax) and responses to submaximal cycling (100 and 150 watts) were assessed in a laboratory cycling test. Peak power output significantly improved within both groups (9.6 ± 4.8% and 12.6 ± 8.9% for HG and NG, respectively) with no significant interaction (p = 0.277). However, VO2max only significantly increased after training in hypoxia from 45.4 ± 10.1 to 50.0 ± 9.8 ml/min/kg (10.8 ± 6.0%; p = 0.002) with no significant interaction (p = 0.146). The maximal O2-pulse improved within the HG and demonstrated a significant interaction (p = 0.040). One-legged cycling training significantly improved VO2max and peak power output. Training under hypoxic conditions may generate greater effects on VO2max than a similar training in normoxia and is considered as a promising training method for improving cardiorespiratory fitness. Key points Nine sessions of one-legged high-intensity interval training significantly improved physical fitness. One-legged hypoxic

  14. Cardiorespiratory Effects of One-Legged High-Intensity Interval Training in Normoxia and Hypoxia: A Pilot Study.

    PubMed

    Menz, Verena; Semsch, Mona; Mosbach, Florian; Burtscher, Martin

    2016-06-01

    A higher-than-average maximal oxygen consumption (VO2max), is closely associated with decreased morbidity and mortality and improved quality of life and acts as a marker of cardiorespiratory fitness. Although there is no consensus about an optimal training method to enhance VO2max, nevertheless training of small muscle groups and repeated exposure to hypoxia seem to be promising approaches. Therefore, this study was aimed at gaining innovative insights into the effects of small muscle group training in normoxia and hypoxia. Thirteen healthy participants were randomly assigned to the hypoxic (HG, n = 7) or normoxic (NG, n = 6) training group. Both groups completed nine high-intensity interval training sessions in 3 wks. The NG performed the training in normoxia (FiO2: 0.21; ~ 600 m) and the HG in hypoxia (FiO2: 0.126; ~ 4500 m). Each session consisted of 4 x 4 min one-legged cycling at 90% of maximal heart rate separated by 4 min recovery periods. Before and after the intervention period, VO2max and peak power output (Wmax) and responses to submaximal cycling (100 and 150 watts) were assessed in a laboratory cycling test. Peak power output significantly improved within both groups (9.6 ± 4.8% and 12.6 ± 8.9% for HG and NG, respectively) with no significant interaction (p = 0.277). However, VO2max only significantly increased after training in hypoxia from 45.4 ± 10.1 to 50.0 ± 9.8 ml/min/kg (10.8 ± 6.0%; p = 0.002) with no significant interaction (p = 0.146). The maximal O2-pulse improved within the HG and demonstrated a significant interaction (p = 0.040). One-legged cycling training significantly improved VO2max and peak power output. Training under hypoxic conditions may generate greater effects on VO2max than a similar training in normoxia and is considered as a promising training method for improving cardiorespiratory fitness. Key pointsNine sessions of one-legged high-intensity interval training significantly improved physical fitness.One-legged hypoxic

  15. Differential Cardiac Effects of Aerobic Interval Training Versus Moderate Continuous Training in a Patient with Schizophrenia: A Case Report

    PubMed Central

    Herbsleb, Marco; Mühlhaus, Tobias; Bär, Karl-Jürgen

    2014-01-01

    Increased cardiovascular morbidity and mortality rates for patients with schizophrenia are reported to contribute to their reduced life expectancy. Common reasons for increased cardiac mortality rates include cigarette smoking, obesity, dyslipidemia, diabetes, and poorer health behavior in general. The majority of excess mortality among people with schizophrenia is caused by cardiovascular complications. Reduced vagal activity might be one important mechanism leading to this increased cardiac mortality and has been consistently described in patients and their healthy first-degree relatives. In this case study, we compared two different aerobic exercise regimes in one patient with chronic schizophrenia to investigate their effects on cardiovascular regulation. The patient completed a 6-week period of moderate continuous training (CT) followed by a 6-week period of interval training (IT), each regime two times per week, on a stationary bicycle. This was followed by a 6-week period of detraining. Primary outcome measures examined heart rate (HR) and heart rate variability (HRV) at rest while secondary measures assessed fitness parameters such as the ventilatory threshold 1 (VT1). We observed that IT was far more effective than moderate CT in increasing HRV, as indicated by root mean of squared successive difference (improvement to baseline 27 versus 18%), and reducing resting HR (−14 versus 0%). Improvement in VT1 (21 versus −1%) was only observed after IT. Our study provides preliminary data that the type of intervention is highly influential for improving cardiac function in patients with schizophrenia. While cardiovascular function might be influenced by CT to some degree, no such effect was present in this patient with schizophrenia. In addition, the beneficial effect of IT on HR regulation vanished completely after a very short period of detraining after the intervention. PMID:25221528

  16. Quantitative immunofluorescence microscopy of subcellular GLUT4 distribution in human skeletal muscle: effects of endurance and sprint interval training

    PubMed Central

    Bradley, Helen; Shaw, Christopher S.; Worthington, Philip L.; Shepherd, Sam O.; Cocks, Matthew; Wagenmakers, Anton J. M.

    2014-01-01

    Abstract Increases in insulin‐mediated glucose uptake following endurance training (ET) and sprint interval training (SIT) have in part been attributed to concomitant increases in glucose transporter 4 (GLUT4) protein content in skeletal muscle. This study used an immunofluorescence microscopy method to investigate changes in subcellular GLUT4 distribution and content following ET and SIT. Percutaneous muscle biopsy samples were taken from the m. vastus lateralis of 16 sedentary males in the overnight fasted state before and after 6 weeks of ET and SIT. An antibody was fully validated and used to show large (> 1 μm) and smaller (<1 μm) GLUT4‐containing clusters. The large clusters likely represent trans‐Golgi network stores and the smaller clusters endosomal stores and GLUT4 storage vesicles (GSVs). Density of GLUT4 clusters was higher at the fibre periphery especially in perinuclear regions. A less dense punctate distribution was seen in the rest of the muscle fibre. Total GLUT4 fluorescence intensity increased in type I and type II fibres following both ET and SIT. Large GLUT4 clusters increased in number and size in both type I and type II fibres, while the smaller clusters increased in size. The greatest increases in GLUT4 fluorescence intensity occurred within the 1 μm layer immediately adjacent to the PM. The increase in peripheral localisation and protein content of GLUT4 following ET and SIT is likely to contribute to the improvements in glucose homeostasis observed after both training modes. PMID:25052490

  17. Photogeneration of reactive transient species upon irradiation of natural water samples: Formation quantum yields in different spectral intervals, and implications for the photochemistry of surface waters.

    PubMed

    Marchisio, Andrea; Minella, Marco; Maurino, Valter; Minero, Claudio; Vione, Davide

    2015-04-15

    Chromophoric dissolved organic matter (CDOM) in surface waters is a photochemical source of several transient species such as CDOM triplet states ((3)CDOM*), singlet oxygen ((1)O2) and the hydroxyl radical (OH). By irradiation of lake water samples, it is shown here that the quantum yields for the formation of these transients by CDOM vary depending on the irradiation wavelength range, in the order UVB > UVA > blue. A possible explanation is that radiation at longer wavelengths is preferentially absorbed by the larger CDOM fractions, which show lesser photoactivity compared to smaller CDOM moieties. The quantum yield variations in different spectral ranges were definitely more marked for (3)CDOM* and OH compared to (1)O2. The decrease of the quantum yields with increasing wavelength has important implications for the photochemistry of surface waters, because long-wavelength radiation penetrates deeper in water columns compared to short-wavelength radiation. The average steady-state concentrations of the transients ((3)CDOM*, (1)O2 and OH) were modelled in water columns of different depths, based on the experimentally determined wavelength trends of the formation quantum yields. Important differences were found between such modelling results and those obtained in a wavelength-independent quantum yield scenario.

  18. Intertrial-interval effects on sensitivity (A') and response bias (B") in a temporal discrimination by rats.

    PubMed

    Raslear, T G; Shurtleff, D; Simmons, L

    1992-11-01

    Killeen and Fetterman's (1988) behavioral theory of animal timing predicts that decreases in the rate of reinforcement should produce decreases in the sensitivity (A') of temporal discriminations and a decrease in miss and correct rejection rates (decrease in bias toward "long" responses). Eight rats were trained on a 10- versus 0.1-s temporal discrimination with an intertrial interval of 5 s and were subsequently tested on probe days on the same discrimination with intertrial intervals of 1, 2.5, 5, 10, or 20 s. The rate of reinforcement declined for all animals as intertrial interval increased. Although sensitivity (A') decreased with increasing intertrial interval, all rats showed an increase in bias to make long responses.

  19. Effects of sample homogenization on solid phase sediment toxicity

    SciTech Connect

    Anderson, B.S.; Hunt, J.W.; Newman, J.W.; Tjeerdema, R.S.; Fairey, W.R.; Stephenson, M.D.; Puckett, H.M.; Taberski, K.M.

    1995-12-31

    Sediment toxicity is typically assessed using homogenized surficial sediment samples. It has been recognized that homogenization alters sediment integrity and may result in changes in chemical bioavailability through oxidation-reduction or other chemical processes. In this study, intact (unhomogenized) sediment cores were taken from a Van Veen grab sampler and tested concurrently with sediment homogenate from the same sample in order to investigate the effect of homogenization on toxicity. Two different solid-phase toxicity test protocols were used for these comparisons. Results of amphipod exposures to samples from San Francisco Bay indicated minimal difference between intact and homogenized samples. Mean amphipod survival in intact cores relative to homogenates was similar at two contaminated sites. Mean survival was 34 and 33% in intact and homogenized samples, respectively, at Castro Cove. Mean survival was 41% and 57%, respectively, in intact and homogenized samples from Islais Creek. Studies using the sea urchin development protocol, modified for testing at the sediment/water interface, indicated considerably more toxicity in intact samples relative to homogenized samples from San Diego Bay. Measures of metal flux into the overlying water demonstrated greater flux of metals from the intact samples. Zinc flux was five times greater, and copper flux was twice as great in some intact samples relative to homogenates. Future experiments will compare flux of metals and organic compounds in intact and homogenized sediments to further evaluate the efficacy of using intact cores for solid phase toxicity assessment.

  20. Effects of interval between fusion and activation, cytochalasin B treatment, and number of transferred embryos, on cloning efficiency in goats.

    PubMed

    Liu, J; Li, L L; Du, S; Bai, X Y; Zhang, H D; Tang, S; Zhao, M T; Ma, B H; Quan, F S; Zhao, X E; Zhang, Y

    2011-10-01

    To improve the efficiency of somatic cell nuclear transfer (SCNT) in goats, we evaluated the effects of the interval between fusion and activation (1 to 5 h), cytochalasin B (CB) treatment after electrofusion, and the number of transferred embryos on the in vivo and in vitro development of cloned caprine embryos. The majority of the reconstructed embryos had condensed chromosomes and metaphase-like chromosomes at 2 and 3 h after fusion; cleavage and blastocyst rates from those two groups were higher (P < 0.05) than those of embryos activated 1, 4, or 5 h after fusion. Treatment with CB between fusion and activation improved in vitro and in vivo development of nuclear transfer (NT) goat embryos by reducing the fragmentation rate (P < 0.05). Although there were no significant differences in NT efficiency, pregnancy rate and kids born per recipient were increased by transfer of 20 or 30 embryos per recipient compared with 10 embryos. We concluded that CB treatment for 2 to 3 h between fusion and activation was an efficient method for generating cloned goats by somatic cell NT. In addition, increasing the number of embryos transferred to each recipient resulted in more live offspring from fewer recipients.

  1. Effects of interstimulus intervals on behavioral, heart rate, and event-related potential indices of infant engagement and sustained attention

    PubMed Central

    Xie, Wanze; Richards, John E.

    2016-01-01

    Maximizing infant attention to stimulus presentation during an EEG or ERP experiment is important for making valid inferences about the neural correlates of infant cognition. The present study examined the effects of stimulus presentation interstimulus interval (ISI) on behavioral and physiological indices of infant attention including infants’ fixation to visual presentation, the amount of heart rate (HR) change during sustained attention, and ERP components. This study compared an ISI that is typically used in infant EEG/ERP studies (e.g., 1,500–2,000 ms) with two shorter durations (400–600 ms and 600–1,000 ms). Thirty-six infants were tested cross-sectionally at 3, 4.5, and 6 months. It was found that using the short (400–600 ms) and medium (600–1,000 ms) ISIs resulted in more visually fixated trials and reduced frequency of fixation disengagement per experimental block. We also found larger HR changes during sustained attention to both of the shorter ISIs compared with the long ISI, and larger ERP responses when using the medium ISI compared to using the short and long ISIs. These data suggest that utilizing an optimal ISI (e.g., 600– 1,000 ms), which increases the presentation complexity and provides sufficient time for information processing, can promote infant engagement and sustained attention during stimulus presentation. PMID:27159263

  2. Post-feeding larval behaviour in the blowfly, Calliphora vicina: effects on post-mortem interval estimates.

    PubMed

    Arnott, Sophie; Turner, Bryan

    2008-05-20

    Using the rate of development of blowflies colonising a corpse, accumulated degree hours (ADH), or days (ADD), is an established method used by forensic entomologists to estimate the post-mortem interval (PMI). Derived from laboratory experiments, their application to field situations needs care. This study examines the effect of the post-feeding larval dispersal time on the ADH and therefore the PMI estimate. Post-feeding dispersal in blowfly larvae is typically very short in the laboratory but may extend for hours or days in the field, whilst the larvae try to find a suitable pupariation site. Increases in total ADH (to adult eclosion), due to time spent dispersing, are not simply equal to the dispersal time. The pupal period is increased by approximately 2 times the length of the dispersal period. In practice, this can introduce over-estimation errors in the PMI estimate of between 1 and 2 days if the total ADH calculations do not consider the possibility of an extended larval dispersal period.

  3. Sprint interval training (SIT) is an effective method to maintain cardiorespiratory fitness (CRF) and glucose homeostasis in Scottish adolescents

    PubMed Central

    Martin, R; Baker, JS; Young, J; Sculthorpe, N; Grace, FM

    2015-01-01

    The present study examined the physiological impact of a school based sprint interval training (SIT) intervention in replacement of standard physical education (SPE) class on cardio-respiratory fitness (CRF) and glucose homeostasis during the semester following summer vacation. Participants (n=49) were randomly allocated to either intervention (SIT; n=26, aged 16.9 ± 0.3 yrs) or control group who underwent standard physical education (SPE; n=23, aged 16.8 ± 0.6 yrs). CRF (VO2max) and glucose homeostasis were obtained prior-to and following 7 weeks of SIT exercise. Significant group x time interaction was observed for CRF (P < 0.01) with non-significant trends for fasting insulin (P= 0.08), and HOMA-IR (P=0.06). CRF decreased (P < 0.01) in SPE such that POST intervention CRF was significantly lower (P< 0.05) in SPE. Fasting plasma glucose (P < 0.01), insulin (P< 0.01) and HOMA-IR (P< 0.01) increased significantly amongst SPE. The main finding of the present study is that 7-weeks of SIT exercise is an effective method of maintaining (but not improving) CRF and fasting insulin homeostasis amongst school-going adolescents. SIT exercise demonstrates potential as a time efficient physiological adjunct to standard PE class in order to maintain CRF during the school term. PMID:26681833

  4. High intensity interval and endurance training have opposing effects on markers of heart failure and cardiac remodeling in hypertensive rats.

    PubMed

    Holloway, Tanya M; Bloemberg, Darin; da Silva, Mayne L; Simpson, Jeremy A; Quadrilatero, Joe; Spriet, Lawrence L

    2015-01-01

    There has been re-emerging interest and significant work dedicated to investigating the metabolic effects of high intensity interval training (HIIT) in recent years. HIIT is considered to be a time efficient alternative to classic endurance training (ET) that elicits similar metabolic responses in skeletal muscle. However, there is a lack of information on the impact of HIIT on cardiac muscle in disease. Therefore, we determined the efficacy of ET and HIIT to alter cardiac muscle characteristics involved in the development of diastolic dysfunction, such as ventricular hypertrophy, fibrosis and angiogenesis, in a well-established rodent model of hypertension-induced heart failure before the development of overt heart failure. ET decreased left ventricle fibrosis by ~40% (P < 0.05), and promoted a 20% (P<0.05) increase in the left ventricular capillary/fibre ratio, an increase in endothelial nitric oxide synthase protein (P<0.05), and a decrease in hypoxia inducible factor 1 alpha protein content (P<0.05). In contrast, HIIT did not decrease existing fibrosis, and HIIT animals displayed a 20% increase in left ventricular mass (P<0.05) and a 20% decrease in cross sectional area (P<0.05). HIIT also increased brain natriuretic peptide by 50% (P<0.05), in the absence of concomitant angiogenesis, strongly suggesting pathological cardiac remodeling. The current data support the longstanding belief in the effectiveness of ET in hypertension. However, HIIT promoted a pathological adaptation in the left ventricle in the presence of hypertension, highlighting the need for further research on the widespread effects of HIIT in the presence of disease. PMID:25803693

  5. High-intensity interval training on an aquatic treadmill in adults with osteoarthritis: effect on pain, balance, function, and mobility.

    PubMed

    Bressel, Eadric; Wing, Jessica E; Miller, Andrew I; Dolny, Dennis G

    2014-08-01

    Although aquatic exercise is considered a potentially effective treatment intervention for people with osteoarthritis (OA), previous research has focused primarily on calisthenics in a shallow pool with the inherent limitations on regulating exercise intensity. The purpose of this study was to quantify the efficacy of a 6-week aquatic treadmill exercise program on measures of pain, balance, function, and mobility. Eighteen participants (age = 64.5 ± 10.2 years) with knee OA completed a non-exercise control period followed by a 6-week exercise period. Outcome measures included visual analog scales for pain, posturography for balance, sit-to-stand test for function, and a 10-m walk test for mobility. The exercise protocol included balance training and high-intensity interval training (HIT) in an aquatic treadmill using water jets to destabilize while standing and achieve high ratings of perceived exertion (14-19) while walking. In comparison with pretests, participants displayed reduced joint pain (pre = 50.3 ± 24.8 mm vs. post = 15.8 ± 10.6 mm), improved balance (equilibrium pre = 66.6 ± 11.0 vs. post = 73.5 ± 7.1), function (rising index pre = 0.49 ± 0.19% vs. post = 0.33 ± 0.11%), and mobility (walk pre = 8.6 ± 1.4 s vs. post = 7.8 ± 1.1 s) after participating in the exercise protocol (p = 0.03-0.001). The same benefits were not observed after the non-exercise control period. Adherence to the exercise protocol was exceptional and no participants reported adverse effects, suggesting that aquatic treadmill exercise that incorporates balance and HIT training was well tolerated by patients with OA and may be effective at managing symptoms of OA.

  6. High Intensity Interval and Endurance Training Have Opposing Effects on Markers of Heart Failure and Cardiac Remodeling in Hypertensive Rats

    PubMed Central

    Holloway, Tanya M.; Bloemberg, Darin; da Silva, Mayne L.; Simpson, Jeremy A.; Quadrilatero, Joe; Spriet, Lawrence L.

    2015-01-01

    There has been re-emerging interest and significant work dedicated to investigating the metabolic effects of high intensity interval training (HIIT) in recent years. HIIT is considered to be a time efficient alternative to classic endurance training (ET) that elicits similar metabolic responses in skeletal muscle. However, there is a lack of information on the impact of HIIT on cardiac muscle in disease. Therefore, we determined the efficacy of ET and HIIT to alter cardiac muscle characteristics involved in the development of diastolic dysfunction, such as ventricular hypertrophy, fibrosis and angiogenesis, in a well-established rodent model of hypertension-induced heart failure before the development of overt heart failure. ET decreased left ventricle fibrosis by ~40% (P < 0.05), and promoted a 20% (P<0.05) increase in the left ventricular capillary/fibre ratio, an increase in endothelial nitric oxide synthase protein (P<0.05), and a decrease in hypoxia inducible factor 1 alpha protein content (P<0.05). In contrast, HIIT did not decrease existing fibrosis, and HIIT animals displayed a 20% increase in left ventricular mass (P<0.05) and a 20% decrease in cross sectional area (P<0.05). HIIT also increased brain natriuretic peptide by 50% (P<0.05), in the absence of concomitant angiogenesis, strongly suggesting pathological cardiac remodeling. The current data support the longstanding belief in the effectiveness of ET in hypertension. However, HIIT promoted a pathological adaptation in the left ventricle in the presence of hypertension, highlighting the need for further research on the widespread effects of HIIT in the presence of disease. PMID:25803693

  7. Limited Effects of Endurance or Interval Training on Visceral Adipose Tissue and Systemic Inflammation in Sedentary Middle-Aged Men

    PubMed Central

    Cooper, Joshua H. F.; Collins, Blake E. G.; Adams, David R.; Robergs, Robert A.

    2016-01-01

    Purpose. Limited data exists for the effects of sprint-interval training (SIT) and endurance training (ET) on total body composition, abdominal visceral adipose tissue, and plasma inflammation. Moreover, whether “active” or “passive” recovery in SIT provides a differential effect on these measures remains uncertain. Methods. Sedentary middle-aged men (n = 62; 49.5 ± 5.8 y; 29.7 ± 3.7 kg·m2) underwent abdominal computed tomography, dual-energy X-ray absorptiometry, venepuncture, and exercise testing before and after the interventions, which included the following: 12 wks 3 d·wk−1 ET (n = 15; 50–60 min cycling; 80% HRmax), SIT (4–10 × 30 s sprint efforts) with passive (P-SIT; n = 15) or active recovery (A-SIT; n = 15); or nonexercise control condition (CON; n = 14). Changes in cardiorespiratory fitness, whole-body and visceral fat mass, and plasma systemic inflammation were examined. Results. Compared to CON, significant increases in interpolated power output (P-SIT, P < 0.001; ET, P = 0.012; A-SIT, P = 0.041) and test duration (P-SIT, P = 0.001; ET, P = 0.012; A-SIT, P = 0.046) occurred after training. Final VO2 consumption was increased after P-SIT only (P < 0.001). Despite >90% exercise compliance, there was no change in whole-body or visceral fat mass or plasma inflammation (P > 0.05). Conclusion. In sedentary middle-aged men, SIT was a time-effective alternative to ET in facilitating conditioning responses yet was ineffective in altering body composition and plasma inflammation, and compared to passive recovery, evidenced diminished conditioning responses when employing active recovery. PMID:27777795

  8. The effects of calving to first service interval on reproductive performance in normal cows and cows with postpartal disease.

    PubMed

    Dohoo, I R

    1983-11-01

    The relationships between the calving to first service interval and several measures of reproductive performance were evaluated in 1738 lactation records from cows in 32 southern Ontario Holstein herds. Lactation records were divided into three mutually exclusive health categories based on the cows' postpartal disease histories.Relationships between the calving to first service interval and the first service conception rate, number of services per conception and open interval were similar for all three health categories. The first service conception rate was lower and the average number of services per conception higher in cows first bred before 60 days when compared to cows first bred after 60 days. The relationship between the calving to first service interval and the open interval indicated that for each day that breeding was delayed the open interval was extended by 0.86 days.It appeared that overall conception rates may be lower for cows first bred very early or very late, but differences in the overall conception rate were only significant for cows experiencing a reproductive tract infection. Unless very expensive semen is being used, it is suggested that disease free cows be bred at the first heat occurring after 40 days postpartum, and that cows experiencing postpartal disease be bred at the first heat occurring after 60 days postpartum.

  9. The effect of intraspinal bupivacaine versus levobupivacaine on the QTc intervals during caesarean section: a randomized, double-blind, prospective study.

    PubMed

    Dogan, Zafer; Yildiz, Huseyin; Akcay, Ahmet; Coskuner, Ismail; Arikan, Deniz C; Silay, Emin; Akbudak, Ilknur H; Kaya, Hakan; Oksuz, Hafize

    2014-03-01

    The aim of this study was to describe whether or not spinal anaesthesia with bupivacaine versus levobupivacaine has any effects on the QTc interval during caesarean section. Sixty healthy pregnant women scheduled for elective caesarean section were randomized to spinal anaesthesia with either bupivacaine (the bupivacaine group) or levobupivacaine (the levobupivacaine group). ECG recordings were performed prior to spinal anaesthesia at baseline (T1), 5 min. after spinal anaesthesia, but before uterine incision (T2), and after skin closure (T3). QT intervals were calculated and corrected with the patients' heart rate according to the Bazett formula. Compared with baseline values, mean maximum QTc intervals at T2 and T3 were significantly longer in the levobupivacaine group, but only at T2 in the bupivacaine group. In addition, compared with the bupivacaine group, the QTc maximum interval at T3 was significantly longer in the levobupivacaine group. At T2, the QTc maximum intervals were longer than baseline in both groups. By the end of the surgery, the prolongation of the QTc interval had disappeared in the bupivacaine group but not in the levobupivacaine group.

  10. Effect of Minimum Cell Sizes and Confidence Interval Sizes for Special Education Subgroups on School-Level AYP Determinations. Synthesis Report 61

    ERIC Educational Resources Information Center

    Simpson, Mary Ann; Gong, Brian; Marion, Scott

    2006-01-01

    This study addresses three questions: First, considering the full group of students and the special education subgroup, what is the likely effect of minimum cell size and confidence interval size on school-level Adequate Yearly Progress (AYP) determinations? Second, what effects do the changing minimum cell sizes have on inclusion of special…

  11. Effect of sample quantity on the results of ferromagnetic resonance studies of lunar samples

    NASA Technical Reports Server (NTRS)

    Goldberg, J. B.; Crowe, H. R.; Housley, R. M.; Cirlin, E. H.

    1979-01-01

    Quantitative ferromagnetic resonance (FMR) measurements at 9.5 and 35 GHz were made on lunar fines in order to determine the amount of single domain FE(0) and to ascertain the effect of sample quantity on the results of these experiments. Samples containing more than 10 micrograms of Fe(0) in an X-band TE(104) cavity, or more than 0.11 micrograms in a Ka-band cavity can cause errors greater than 1% in the quantitative determination of Fe(0), as well as cause anomalous broadening of the FMR line. Theoretical calculations were derived to show this effect which results from a nonlinear response of the FMR experiment with the sample quantity. Using samples of nominal weights, the amount of Fe(0) determined at 34 GHz was 1.1-1.8 times greater than at 9.5 GHz, while the linewidths increased by a factor of 1.2. As the particle size increases, the ratio of Fe(0) determined at 35 GHz to that determined at 9.5 GHz increases, suggesting that the additional iron is due to larger spheroidal particles which change from multidomain to single domain at the larger fields.

  12. Contrasting effects of a mixed-methods high-intensity interval training intervention in girl football players.

    PubMed

    Wright, Matthew D; Hurst, Christopher; Taylor, Jonathan M

    2016-10-01

    Little is known about the responses of girl athletes to training interventions throughout maturation. This study evaluated group and individual responses to an 8-week, mixed-methods, high-intensity interval training (HIIT) programme in girl football players. Thirty-seven players (age 13.4 ± 1.5 years) were tested for 20-m speed, repeated-sprint ability, change-of-direction speed and level 1 yo-yo intermittent recovery (YYIR). Players were subcategorised into before-, at- and after-PHV (peak height velocity) based on maturity offset. Very likely moderate (25%; ±90% confidence limits = 9.2) improvements occurred in YYIR, but data were unclear in players before-PHV with moderate individual differences in response. Decrements in repeated-sprint ability were most likely very large (6.5%; ±3.2) before-PHV, and likely moderate (1.7%; ±1.0) at-PHV. Data were unclear after-PHV. A very likely moderate (2.7%; ±1.0) decrement occurred in change-of-direction speed at-PHV while there was a very likely increase (-2.4%; ±1.3) in after-PHV players. Possibly small (-1.1%; ±1.4) improvements in 20-m speed occurred before-PHV but the effect was otherwise unclear with moderate to large individual differences. These data reflect specific responses to training interventions in girls of different biological maturity, while highlighting individual responses to HIIT interventions. This can assist practitioners in providing effective training prescription.

  13. Effectiveness of high-intensity interval training on the mental and physical health of people with chronic schizophrenia

    PubMed Central

    Wu, Meng Hsiu; Lee, Chin Pang; Hsu, Shih Chieh; Chang, Chia Ming; Chen, Ching Yen

    2015-01-01

    Background Low-volume high-intensity interval training (HIIT) is emerging as a time-efficient exercise strategy for improving cardiorespiratory fitness and for controlling blood sugar levels and hypertension. In addition, patient acceptance of HIIT may improve adherence to exercise programs. This study evaluated the effectiveness of HIIT for improving the mental and physical health of people with chronic schizophrenia. Methods Twenty patients attending a psychiatric day care unit volunteered for an 8-week program of HIIT. Blood pressure, resting heart rate, body weight, body mass index, waist and hip circumference, and waist-to-hip ratio were measured weekly. The Positive and Negative Syndrome Scale score was recorded at baseline and at the end of the study. Beck Depression Inventory (BDI) and Beck Anxiety Inventory (BAI) scores were recorded every 2 weeks. Results Statistically significant changes occurred in the physical and mental parameters measured in the 18 patients who completed the study. Body weight, body mass index, resting heart rate, and pulse pressure decreased significantly. Mean arterial pressure and diastolic blood pressure increased significantly. Mental health scores improved, with the Negative Scale score decreasing from 31.17±5.95 to 27.78±3.57 (P<0.01) and the General Psychopathology Scale score from 14.28±2.16 to 13.00±1.72 (P<0.01). Positive Scale scores changed, but not significantly, from 12.28±2.27 to 12.33±2.00 (P=0.729). Scores on the BDI (from 19.56±15.28 to 15.89±14.33, P<0.001) and BAI (from 13.67±13.83 to 10.06±11.18, P=0.003) both improved significantly. Conclusion This study demonstrated that HIIT has positive effects on the physical and mental health of patients with chronic schizophrenia. PMID:26060400

  14. The Effect of CardioWaves Interval Training on Resting Blood Pressure, Resting Heart Rate, and Mind-Body Wellness

    PubMed Central

    NIELSON, CAMILLA M.; LOCKHART, BARBARA D.; HAGER, RONALD L.; GEORGE, JAMES D.; EGGETT, DENNIS L.; STEFFEN, PATRICK R.; MITCHELL, ULRIKE H.; BAILEY, BRUCE W.

    2016-01-01

    An experimental study to examine the effects of CardioWaves interval training (CWIT) and continuous training (CT) on resting blood pressure, resting heart rate, and mind-body wellness. Fifty-two normotensive (blood pressure <120/80 mmHg), pre-hypertensive (120–139/80–89 mmHg), and hypertensive (>140/90 mmHg) participants were randomly assigned and equally divided between the CWIT and CT groups. Both groups participated in the assigned exercise protocol 30 minutes per day, four days per week for eight weeks. Resting blood pressure, resting heart rate, and mind-body wellness were measured pre- and post-intervention. A total of 47 participants (15 females and 32 males) were included in the analysis. The CWIT group had a non-significant trend of reduced systolic blood pressure (SBP) and increased diastolic blood pressure (DBP) while the CT group had a statistically significant decrease in awake SBP (p = 0.01) and total SBP (p = 0.01) and a non-significant decrease in DBP. With both groups combined, the female participants had a statistically significant decrease in awake SBP (p = 0.002), asleep SBP (p = 0.01), total SBP (p = 0.003), awake DBP (p = 0.02), and total DBP (p = 0.05). The male participants had an increase in SBP and DBP with total DBP showing a statistically significant increase (p = 0.05). Neither group had a consistent change in resting heart rate. Both groups showed improved mind-body wellness. CWIT and CT reduced resting blood pressure, with CT having a greater effect. Resting heart rate did not change in either group. Additionally, both CWIT and CT improved mind-body wellness. PMID:27182421

  15. Contrasting effects of a mixed-methods high-intensity interval training intervention in girl football players.

    PubMed

    Wright, Matthew D; Hurst, Christopher; Taylor, Jonathan M

    2016-10-01

    Little is known about the responses of girl athletes to training interventions throughout maturation. This study evaluated group and individual responses to an 8-week, mixed-methods, high-intensity interval training (HIIT) programme in girl football players. Thirty-seven players (age 13.4 ± 1.5 years) were tested for 20-m speed, repeated-sprint ability, change-of-direction speed and level 1 yo-yo intermittent recovery (YYIR). Players were subcategorised into before-, at- and after-PHV (peak height velocity) based on maturity offset. Very likely moderate (25%; ±90% confidence limits = 9.2) improvements occurred in YYIR, but data were unclear in players before-PHV with moderate individual differences in response. Decrements in repeated-sprint ability were most likely very large (6.5%; ±3.2) before-PHV, and likely moderate (1.7%; ±1.0) at-PHV. Data were unclear after-PHV. A very likely moderate (2.7%; ±1.0) decrement occurred in change-of-direction speed at-PHV while there was a very likely increase (-2.4%; ±1.3) in after-PHV players. Possibly small (-1.1%; ±1.4) improvements in 20-m speed occurred before-PHV but the effect was otherwise unclear with moderate to large individual differences. These data reflect specific responses to training interventions in girls of different biological maturity, while highlighting individual responses to HIIT interventions. This can assist practitioners in providing effective training prescription. PMID:26881963

  16. Effect of sample stratification on dairy GWAS results

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background Artificial insemination and genetic selection are major factors contributing to population stratification in dairy cattle. In this study, we analyzed the effect of sample stratification and the effect of stratification correction on results of a dairy genome-wide association study (GWAS)....

  17. A validation study concerning the effects of interview content, retention interval, and grade on children’s recall accuracy for dietary intake and/or physical activity

    PubMed Central

    Baxter, Suzanne D.; Hitchcock, David B.; Guinn, Caroline H.; Vaadi, Kate K.; Puryear, Megan P.; Royer, Julie A.; McIver, Kerry L.; Dowda, Marsha; Pate, Russell R.; Wilson, Dawn K.

    2014-01-01

    Background Practitioners and researchers are interested in assessing children’s dietary intake and physical activity together to maximize resources and minimize subject burden. Objective To investigate differences in dietary and/or physical-activity recall accuracy by content (diet-only; physical-activity-only; diet-&-physical-activity), retention interval (same-day-recalls-in-the-afternoon; previous-day-recalls-in-the-morning), and grade (third; fifth). Design Children (n=144; 66% African American, 13% White, 12% Hispanic, 9% Other; 50% girls) from four schools were randomly selected for interviews about one of three contents. Each content group was equally divided by retention interval, each equally divided by grade, each equally divided by sex. Information concerning diet and physical activity at school was validated with school-provided breakfast and lunch observations, and accelerometry, respectively. Dietary accuracy measures were food-item omission and intrusion rates, and kilocalorie correspondence rate and inflation ratio. Physical activity accuracy measures were absolute and arithmetic differences for moderate-to-vigorous-physical-activity minutes. Statistical analyses performed For each accuracy measure, linear models determined effects of content, retention interval, grade, and their two-way and three-way interactions; ethnicity and sex were control variables. Results Content was significant within four interactions: intrusion rate (content-×-retention-interval-×-grade; p=.0004), correspondence rate (content-×-grade; p=.0004), inflation ratio (content-×-grade; p=.0104), and arithmetic difference (content-×-retention-interval-×-grade; p=.0070). Retention interval was significant for correspondence rate (p=.0004), inflation ratio (p=.0014), and three interactions: omission rate (retention-interval-×-grade; p=.0095), intrusion rate, and arithmetic difference (both already mentioned). Grade was significant for absolute difference (p=.0233) and five

  18. The effect of high intensity interval training on cardioprotection against ischemia-reperfusion injury in wistar rats

    PubMed Central

    Rahimi, Mostafa; Shekarforoush, Shahnaz; Asgari, Ali Reza; Khoshbaten, Ali; Rajabi, Hamid; Bazgir, Behzad; Mohammadi, Mohammad Taghi; Sobhani, Vahid; Shakibaee, Abolfazl

    2015-01-01

    The aims of the present study were to determine whether short term high intensity interval training (HIIT) could protect the heart against ischemia reperfusion (IR) injury; and if so, to evaluate how long the exercise-associated protection can be lasted. Sixty-three rats were randomly assigned into sedentary (n = 15), sham (n = 7), and exercise groups (n = 41). Rats in the exercise groups performed 5 consecutive days of HIIT on treadmill: 5 min warm up with 50 % VO2max, 6×2 min with 95-105 % VO2max (about 40 to 45 m/min), 5×2 min recovery with 65-75 % VO2max (about 28 to 32 m/min), and 3 min cool down with 50 % VO2max, all at 0 % grade. Animals exposed to an in vivo cardiac IR surgery, performed at days 1, 7, and 14 following the final exercise session. Ischemia-induced arrhythmias, myocardial infarct size (IS), plasma lactate dehydrogenase (LDH) and creatine kinase (CK) activities were measured in all animals. Compared to sedentary rats, exercised animals sustained less IR injury as evidenced by a lower size of infarction and lower levels of LDH and CK at day one and day 7 post exercise. In comparison of sedentary group, IS significantly decreased in EX-IR1 and EX-IR7 groups (50 and 35 %, respectively), but not in EX-IR14 group (19 %). The exercise-induced cardioprotection disappeared 14 days following exercise cessation. There were no significant changes in ischemia-induced arrhythmia between exercised and sedentary rats. The results clearly demonstrate that HIIT protects the heart against myocardial IR injury. This protective effect can be sustained for at least one week following the cessation of the training. PMID:26417361

  19. No Untoward Effect of Long-Term Ketoconazole Administration on Electrocardiographic QT Interval in Patients with Cushing's Disease.

    PubMed

    De Martin, Martina; Toja, Paola Maria; Goulene, Karine; Radaelli, Piero; Cavagnini, Francesco; Stramba-Badiale, Marco; Pecori Giraldi, Francesca

    2016-04-01

    Ketoconazole is listed among drugs that prolong QT interval and may increase the risk of torsade de pointes, a severe ventricular arrhythmia. This compound has recently been approved for treatment of Cushing's syndrome, a severe endocrine disorder. These patients harbour several risk factors for prolonged QT interval, for example hypokalaemia and left ventricular hypertrophy, but no study has evaluated whether administration of ketoconazole affects their QT interval. The aim of this study was to assess the QT interval in patients with Cushing's disease during long-term administration of ketoconazole. Electrocardiograms from 15 patients with Cushing's disease (12 women, 3 men, age: 37.8 ± 2.66 years) on ketoconazole treatment (100 mg-800 mg qd) for 1 month to 12 years were reviewed retrospectively. QT interval was measured and corrected for heart rate (QTc). Measurements before and during ketoconazole treatment were compared and any abnormal QTc value recorded. Concurrent medical therapies were also documented. On average, QTc was superimposable before and during ketoconazole treatment (393.2 ± 7.17 versus 403.3 ± 6.05 msec. in women; 424.3 ± 23.54 versus 398.0 ± 14.93 msec. in men, N.S.). QTc normalized on ketoconazole in one man with prolonged QTc prior to treatment; no abnormal QTc was observed in any other patient during the entire observation period, even during concurrent treatment with other QT-prolonging drugs. In conclusion, long-term ketoconazole administration does not appear to be associated with significant prolongation of QT interval in patients with Cushing's disease. ECG monitoring can follow recommendations drawn for other low-risk QT-prolonging drugs with attention to specific risk factors, for example hypokalaemia and drug interactions.

  20. The evaluation and management of drug effects on cardiac conduction (PR and QRS intervals) in clinical development.

    PubMed

    Nada, Adel; Gintant, Gary A; Kleiman, Robert; Gutstein, David E; Gottfridsson, Christer; Michelson, Eric L; Strnadova, Colette; Killeen, Matthew; Geiger, Mary Jane; Fiszman, Mónica L; Koplowitz, Luana Pesco; Carlson, Glenn F; Rodriguez, Ignacio; Sager, Philip T

    2013-04-01

    Recent advances in electrocardiographic monitoring and waveform analysis have significantly improved the ability to detect drug-induced changes in cardiac repolarization manifested as changes in the QT/corrected QT interval. These advances have also improved the ability to detect drug-induced changes in cardiac conduction. This White Paper summarizes current opinion, reached by consensus among experts at the Cardiac Safety Research Consortium, on the assessment of electrocardiogram-based safety measurements of the PR and QRS intervals, representing atrioventricular and ventricular conduction, respectively, during drug development.

  1. What effect does VOC sampling time have on derived OH reactivity?

    NASA Astrophysics Data System (ADS)

    Sonderfeld, Hannah; White, Iain R.; Goodall, Iain C. A.; Hopkins, James R.; Lewis, Alastair C.; Koppmann, Ralf; Monks, Paul S.

    2016-05-01

    State-of-the-art techniques allow for rapid measurements of total OH reactivity. Unknown sinks of OH and oxidation processes in the atmosphere have been attributed to what has been termed "missing" OH reactivity. Often overlooked are the differences in timescales over which the diverse measurement techniques operate. Volatile organic compounds (VOCs) acting as sinks of OH are often measured by gas chromatography (GC) methods which provide low-frequency measurements on a timescale of hours, while sampling times are generally only a few minutes. Here, the effect of the sampling time and thus the contribution of unmeasured VOC variability on OH reactivity is investigated. Measurements of VOC mixing ratios by proton transfer reaction time-of-flight mass spectrometry (PTR-ToF-MS) conducted during two field campaigns (ClearfLo and PARADE) in an urban and a semi-rural environment were used to calculate OH reactivity. VOCs were selected to represent variability for different compound classes. Data were averaged over different time intervals to simulate lower time resolutions and were then compared to the mean hourly OH reactivity. The results show deviations in the range of 1 to 25 %. The observed impact of VOC variability is found to be greater for the semi-rural site.The selected compounds were scaled by the contribution of their compound class to the total OH reactivity from VOCs based on concurrent gas chromatography measurements conducted during the ClearfLo campaign. Prior to being scaled, the variable signal of aromatic compounds results in larger deviations in OH reactivity for short sampling intervals compared to oxygenated VOCs (OVOCs). However, once scaled with their lower share during the ClearfLo campaign, this effect was reduced. No seasonal effect on the OH reactivity distribution across different VOCs was observed at the urban site.

  2. Estimating the effectiveness of further sampling in species inventories

    USGS Publications Warehouse

    Keating, K.A.; Quinn, J.F.; Ivie, M.A.; Ivie, L.L.

    1998-01-01

    Estimators of the number of additional species expected in the next ??n samples offer a potentially important tool for improving cost-effectiveness of species inventories but are largely untested. We used Monte Carlo methods to compare 11 such estimators, across a range of community structures and sampling regimes, and validated our results, where possible, using empirical data from vascular plant and beetle inventories from Glacier National Park, Montana, USA. We found that B. Efron and R. Thisted's 1976 negative binomial estimator was most robust to differences in community structure and that it was among the most accurate estimators when sampling was from model communities with structures resembling the large, heterogeneous communities that are the likely targets of major inventory efforts. Other estimators may be preferred under specific conditions, however. For example, when sampling was from model communities with highly even species-abundance distributions, estimates based on the Michaelis-Menten model were most accurate; when sampling was from moderately even model communities with S=10 species or communities with highly uneven species-abundance distributions, estimates based on Gleason's (1922) species-area model were most accurate. We suggest that use of such methods in species inventories can help improve cost-effectiveness by providing an objective basis for redirecting sampling to more-productive sites, methods, or time periods as the expectation of detecting additional species becomes unacceptably low.

  3. Effects of 4 Weeks of High-Intensity Interval Training and β-Hydroxy-β-Methylbutyric Free Acid Supplementation on the Onset of Neuromuscular Fatigue.

    PubMed

    Miramonti, Amelia A; Stout, Jeffrey R; Fukuda, David H; Robinson, Edward H; Wang, Ran; La Monica, Michael B; Hoffman, Jay R

    2016-03-01

    This study investigated the effects of high-intensity interval training (HIIT) and β-hydroxy-β-methylbutyric free acid (HMB) supplementation on physical working capacity at the onset of neuromuscular fatigue threshold (PWC(FT)). Thirty-seven participants (22 men, 15 women; 22.8 ± 3.4 years) completed an incremental cycle ergometer test (graded exercise test [GXT]); electromyographic amplitude from the right vastus lateralis was recorded. Assessments occurred preceding (PRE) and after 4 weeks of supplementation (POST). Participants were randomly assigned to control (C, n = 9), placebo (P, n = 14), or supplementation (S, n = 14) groups. Both P and S completed 12 HIIT sessions, whereas C maintained normal diet and activity patterns. The PWC(FT) (W) was determined using the maximal perpendicular distance (D(MAX)) method. Electromyographic amplitude (μVrms) over time was used to generate a cubic regression. Onset of fatigue (TF) was the x-value of the point on the regression that was at D(MAX) from a line between the first and last data points. The PWC(FT) was estimated using TF and GXT power-output increments. The 2-way analysis of variance (ANOVA) (group × time) resulted in a significant interaction for PWC(FT) (F = 6.69, p = 0.004). Post hoc analysis with 1-way ANOVA resulted in no difference in PWC(FT) among groups at PRE (F = 0.87, p = 0.43); however, a difference in PWC(FT) was shown for POST (F = 5.46, p = 0.009). Post hoc analysis among POST values revealed significant differences between S and both P (p = 0.034) and C (p = 0.003). No differences (p = 0.226) were noted between P and C. Paired samples t-tests detected significant changes after HIIT for S (p < 0.001) and P (p = 0.016), but no change in C (p = 0.473). High-intensity interval training increased PWC(FT), but HMB with HIIT was more effective than HIIT alone. Furthermore, it seems that adding HMB supplementation with HIIT in untrained men and women may further improve endurance performance

  4. Confidence interval estimation for an empirical model quantifying the effect of soil moisture and plant development on soybean (Glycine max (L.) Merr.) leaf conductance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this work, we address uncertainty analysis for a model, presented in a companion paper, quantifying the effect of soil moisture and plant development on soybean (Glycine max (L.) Merr.) leaf conductance. To achieve this we present several methods for confidence interval estimation. Estimation ...

  5. High-Intensity Cycling Training: The Effect of Work-to-Rest Intervals on Running Performance Measures.

    PubMed

    Kavaliauskas, Mykolas; Aspe, Rodrigo R; Babraj, John

    2015-08-01

    The work-to-rest ratio during cycling-based high-intensity interval training (HIT) could be important in regulating physiological and performance adaptations. We sought to determine the effectiveness of cycling-based HIT with different work-to-rest ratios for long-distance running. Thirty-two long-distance runners (age: 39 ± 8 years; sex: 14 men, 18 women; average weekly running training volume: 25 miles) underwent baseline testing (3-km time-trial, V[Combining Dot Above]O2peak and time to exhaustion, and Wingate test) before a 2-week matched-work cycling HIT of 6 × 10-second sprints with different rest periods (30 seconds [R30], 80 seconds [R80], 120 seconds [R120], or control). Three-kilometer time trial was significantly improved in the R30 group only (3.1 ± 4.0%, p = 0.04), whereas time to exhaustion was significantly increased in the 2 groups with a lower work-to-rest ratio (R30 group 6.4 ± 6.3%, p = 0.003 vs. R80 group 4.4 ± 2.7%, p = 0.03 vs. R120 group 1.9 ± 5.0%, p = 0.2). However, improvements in average power production were significantly greater with a higher work-to-rest ratio (R30 group 0.3 ± 4.1%, p = 0.8 vs. R80 group 4.6 ± 4.2%, p = 0.03 vs. R120 group 5.3 ± 5.9%, p = 0.02), whereas peak power significantly increased only in the R80 group (8.5 ± 8.2%, p = 0.04) but not in the R30 group (4.3 ± 6.1%, p = 0.3) or in the R120 group (7.1 ± 7.9%, p = 0.09). Therefore, cycling-based HIT is an effective way to improve running performance, and the type and magnitude of adaptation is dependent on the work-to-rest ratio. PMID:26203737

  6. Determination of the effective sample thickness via radiative capture

    NASA Astrophysics Data System (ADS)

    Hurst, A. M.; Summers, N. C.; Szentmiklósi, L.; Firestone, R. B.; Basunia, M. S.; Escher, J. E.; Sleaford, B. W.

    2015-11-01

    A procedure for determining the effective thickness of non-uniform irregular-shaped samples via radiative capture is described. In this technique, partial γ -ray production cross sections of a compound nucleus produced in a neutron-capture reaction are measured using Prompt Gamma Activation Analysis and compared to their corresponding standardized absolute values. For the low-energy transitions, the measured cross sections are lower than their standard values due to significant photoelectric absorption of the γ rays within the bulk-sample volume itself. Using standard theoretical techniques, the amount of γ -ray self absorption and neutron self shielding can then be calculated by iteratively varying the sample thickness until the observed cross sections converge with the known standards. The overall attenuation, thus, provides a measure of the effective sample thickness illuminated by the neutron beam. This procedure is illustrated through radiative neutron capture using powdered oxide samples comprising enriched 186W and 182W from which their tungsten-equivalent effective thicknesses are deduced to be 0.077(3) mm and 0.042(8) mm, respectively.

  7. Determination of the effective sample thickness via radiative capture

    DOE PAGES

    Hurst, A. M.; Summers, N. C.; Szentmiklosi, L.; Firestone, R. B.; Basunia, M. S.; Escher, J. E.; Sleaford, B. W.

    2015-09-14

    Our procedure for determining the effective thickness of non-uniform irregular-shaped samples via radiative capture is described. In this technique, partial γ-ray production cross sections of a compound nucleus produced in a neutron-capture reaction are measured using Prompt Gamma Activation Analysis and compared to their corresponding standardized absolute values. For the low-energy transitions, the measured cross sections are lower than their standard values due to significant photoelectric absorption of the γ rays within the bulk-sample volume itself. Using standard theoretical techniques, the amount of γ-ray self absorption and neutron self shielding can then be calculated by iteratively varying the sample thicknessmore » until the observed cross sections converge with the known standards. The overall attenuation provides a measure of the effective sample thickness illuminated by the neutron beam. This procedure is illustrated through radiative neutron capture using powdered oxide samples comprising enriched 186W and 182W from which their tungsten-equivalent effective thicknesses are deduced to be 0.077(3) mm and 0.042(8) mm, respectively.« less

  8. Determination of the effective sample thickness via radiative capture

    SciTech Connect

    Hurst, A. M.; Summers, N. C.; Szentmiklosi, L.; Firestone, R. B.; Basunia, M. S.; Escher, J. E.; Sleaford, B. W.

    2015-09-14

    Our procedure for determining the effective thickness of non-uniform irregular-shaped samples via radiative capture is described. In this technique, partial γ-ray production cross sections of a compound nucleus produced in a neutron-capture reaction are measured using Prompt Gamma Activation Analysis and compared to their corresponding standardized absolute values. For the low-energy transitions, the measured cross sections are lower than their standard values due to significant photoelectric absorption of the γ rays within the bulk-sample volume itself. Using standard theoretical techniques, the amount of γ-ray self absorption and neutron self shielding can then be calculated by iteratively varying the sample thickness until the observed cross sections converge with the known standards. The overall attenuation provides a measure of the effective sample thickness illuminated by the neutron beam. This procedure is illustrated through radiative neutron capture using powdered oxide samples comprising enriched 186W and 182W from which their tungsten-equivalent effective thicknesses are deduced to be 0.077(3) mm and 0.042(8) mm, respectively.

  9. Exploring effective sampling design for monitoring soil organic carbon in degraded Tibetan grasslands.

    PubMed

    Chang, Xiaofeng; Bao, Xiaoying; Wang, Shiping; Zhu, Xiaoxue; Luo, Caiyun; Zhang, Zhenhua; Wilkes, Andreas

    2016-05-15

    The effects of climate change and human activities on grassland degradation and soil carbon stocks have become a focus of both research and policy. However, lack of research on appropriate sampling design prevents accurate assessment of soil carbon stocks and stock changes at community and regional scales. Here, we conducted an intensive survey with 1196 sampling sites over an area of 190 km(2) of degraded alpine meadow. Compared to lightly degraded meadow, soil organic carbon (SOC) stocks in moderately, heavily and extremely degraded meadow were reduced by 11.0%, 13.5% and 17.9%, respectively. Our field survey sampling design was overly intensive to estimate SOC status with a tolerable uncertainty of 10%. Power analysis showed that the optimal sampling density to achieve the desired accuracy would be 2, 3, 5 and 7 sites per 10 km(2) for lightly, moderately, heavily and extremely degraded meadows, respectively. If a subsequent paired sampling design with the optimum sample size were performed, assuming stock change rates predicted by experimental and modeling results, we estimate that about 5-10 years would be necessary to detect expected trends in SOC in the top 20 cm soil layer. Our results highlight the utility of conducting preliminary surveys to estimate the appropriate sampling density and avoid wasting resources due to over-sampling, and to estimate the sampling interval required to detect an expected sequestration rate. Future studies will be needed to evaluate spatial and temporal patterns of SOC variability. PMID:26985730

  10. Effect of creatine supplementation during the last week of gestation on birth intervals, stillbirth, and preweaning mortality in pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We hypothesized that creatine supplementation would reduce birth intervals, stillbirth rate, and preweaning survival in pigs because of its reported improvement of athletic performance in humans. In Exp. 1, gilts (n = 42) and first parity sows (n = 75) were mated at estrus. Beginning on d 110 of ges...

  11. Peer effects on obesity in a sample of European children.

    PubMed

    Gwozdz, Wencke; Sousa-Poza, Alfonso; Reisch, Lucia A; Bammann, Karin; Eiben, Gabriele; Kourides, Yiannis; Kovács, Éva; Lauria, Fabio; Konstabel, Kenn; Santaliestra-Pasias, Alba M; Vyncke, Krishna; Pigeot, Iris

    2015-07-01

    This study analyzes peer effects on childhood obesity using data from the first two waves of the IDEFICS study, which applies several anthropometric and other measures of fatness to approximately 14,000 children aged two to nine participating in both waves in 16 regions of eight European countries. Peers are defined as same-sex children in the same school and age group. The results show that peer effects do exist in this European sample but that they differ among both regions and different fatness measures. Peer effects are larger in Spain, Italy, and Cyprus--the more collectivist regions in our sample--while waist circumference generally gives rise to larger peer effects than BMI. We also provide evidence that parental misperceptions of their own children's weight goes hand in hand with fatter peer groups, supporting the notion that in making such assessments, parents compare their children's weight with that of friends and schoolmates.

  12. Peer effects on obesity in a sample of European children.

    PubMed

    Gwozdz, Wencke; Sousa-Poza, Alfonso; Reisch, Lucia A; Bammann, Karin; Eiben, Gabriele; Kourides, Yiannis; Kovács, Éva; Lauria, Fabio; Konstabel, Kenn; Santaliestra-Pasias, Alba M; Vyncke, Krishna; Pigeot, Iris

    2015-07-01

    This study analyzes peer effects on childhood obesity using data from the first two waves of the IDEFICS study, which applies several anthropometric and other measures of fatness to approximately 14,000 children aged two to nine participating in both waves in 16 regions of eight European countries. Peers are defined as same-sex children in the same school and age group. The results show that peer effects do exist in this European sample but that they differ among both regions and different fatness measures. Peer effects are larger in Spain, Italy, and Cyprus--the more collectivist regions in our sample--while waist circumference generally gives rise to larger peer effects than BMI. We also provide evidence that parental misperceptions of their own children's weight goes hand in hand with fatter peer groups, supporting the notion that in making such assessments, parents compare their children's weight with that of friends and schoolmates. PMID:26115518

  13. Differential Effects of Continuous and Interval Exercise Training on the Atherogenic Index of Plasma in the Non-Obese Young Male

    PubMed Central

    Ezeukwu, Antoninus O; Agwubike, Elias O; Uadia, Patrick O

    2015-01-01

    Background The process of atherogenicity is known to be influenced by exercise. However, appropriate exercise stimulus necessary to generate the response and adaptation in sedentary non-obese individuals has not yet been investigated. The purpose of the present study was to compare the effects of an 8-week continuous training and corresponding interval training on the atherogenic index of plasma in sedentary Nigerian males. Methods Overall, there were 54 male university students that participated in our study, which used a pretest- posttest control group design. Participants (18 males per group) were assigned into continuous, interval and control groups respectively. During the first two weeks, training was done 3 times weekly for 30 minutes each day, and was increased by 5 minutes every 2 weeks. Continuous training was done at 70-84% of heart rate reserve. Interval training was done at 70-84%/30-39% heart rate reserve in 1:2 minutes work/rest intervals, respectively. The control group did not participate in the training. Data collected were analysed using descriptive, paired t-test, analysis of covariance and Bonferroni post-hoc analysis. Results Young sedentary non-obese males were at high risk (atherogenic index of plasma > 0.24) of cardiovascular diseases/conditions. However, continuous training led to significant reductions (p = 0.002) in the atherogenic index of plasma. In contrast, non-significant increase (p = 0.084) followed interval training. After controlling for baseline values, only continuous training still had significant effects on atherogenic index of plasma when compared with other groups. Conclusions Continuous training of vigorous intensity is better than a corresponding interval training protocol as a natural anti-atherogenic method of reducing risk of cardiovascular event in sedentary non-obese males. PMID:27122890

  14. Comparison of dechlorination rates for field DNAPL vs synthetic samples: effect of sample matrix

    NASA Astrophysics Data System (ADS)

    O'Carroll, D. M.; Sakulchaicharoen, N.; Herrera, J. E.

    2015-12-01

    Nanometals have received significant attention in recent years due to their ability to rapidly destroy numerous priority source zone contaminants in controlled laboratory studies. This has led to great optimism surrounding nanometal particle injection for insitu remediation. Reported dechlorination rates vary widely among different investigators. These differences have been ascribed to differences in the iron types (granular, micro, or nano-sized iron), matrix solution chemistry and the morphology of the nZVI surface. Among these, the effects of solution chemistry on rates of reductive dechlorination of various chlorinated compounds have been investigated in several short-term laboratory studies. Variables investigated include the effect of anions or groundwater solutes such as SO4-2, Cl-, NO3-, pH, natural organic matters (NOM), surfactant, and humic acid on dechlorination reaction of various chlorinated compounds such as TCE, carbon tetrachloride (CT), and chloroform (CF). These studies have normally centered on the assessment of nZVI reactivity toward dechlorination of an isolated individual contaminant spiked into a ground water sample under ideal conditions, with limited work conducted using real field samples. In this work, the DNAPL used for the dechlorination study was obtained from a contaminatied site. This approach was selected to adequately simulate a condition where the nZVI suspension was in direct contact with DNAPL and to isolate the dechlorination activity shown by the nZVI from the groundwater matrix effects. An ideal system "synthetic DNAPL" composed of a mixture of chlorinated compounds mimicking the composition of the actual DNAPL was also dechlorinated to evaluate the DNAPL "matrix effect" on NZVI dechlorination activity. This approach allowed us to evaluate the effect of the presence of different types of organic compounds (volatile fatty acids and humic acids) found in the actual DNAPL on nZVI dechlorination activity. This presentation will

  15. The Effect of Asymmetrical Sample Training on Retention Functions for Hedonic Samples in Rats

    ERIC Educational Resources Information Center

    Simmons, Sabrina; Santi, Angelo

    2012-01-01

    Rats were trained in a symbolic delayed matching-to-sample task to discriminate sample stimuli that consisted of the presence of food or the absence of food. Asymmetrical sample training was provided in which one group was initially trained with only the food sample and the other group was initially trained with only the no-food sample. In…

  16. Testing the Effect of Refrigerated Storage on Testate Amoeba Samples.

    PubMed

    Mazei, Yuri; Chernyshov, Viktor; Tsyganov, Andrey N; Payne, Richard J

    2015-11-01

    Samples for analysis of testate amoebae and other protists frequently need to be stored for many months before microscopy. This storage commonly involves refrigeration, but we know that testate amoebae can live and reproduce in these conditions. This raises the question: do communities change during storage and how might this effect the data produced? We analysed Sphagnum samples over a 16-week period to address this question. Our results show no evidence for detectable change. This is a reassuring result supporting much current practice although we suggest that frozen storage or the addition of a fixative may be worthwhile precautions where feasible.

  17. Testing the Effect of Refrigerated Storage on Testate Amoeba Samples.

    PubMed

    Mazei, Yuri; Chernyshov, Viktor; Tsyganov, Andrey N; Payne, Richard J

    2015-11-01

    Samples for analysis of testate amoebae and other protists frequently need to be stored for many months before microscopy. This storage commonly involves refrigeration, but we know that testate amoebae can live and reproduce in these conditions. This raises the question: do communities change during storage and how might this effect the data produced? We analysed Sphagnum samples over a 16-week period to address this question. Our results show no evidence for detectable change. This is a reassuring result supporting much current practice although we suggest that frozen storage or the addition of a fixative may be worthwhile precautions where feasible. PMID:25998536

  18. Approximate inclusion of quantum effects in transition path sampling

    PubMed Central

    Antoniou, Dimitri; Schwartz, Steven D.

    2009-01-01

    We propose a method for incorporating nuclear quantum effects in transition path sampling studies of systems that consist of a few degrees of freedom that must be treated quantum mechanically, while the rest are classical-like. We used the normal mode centroid method to describe the quantum subsystem, which is a method that is not CPU intensive but still reasonably accurate. We applied this mixed centroid∕classical transition path sampling method to a model system that has nontrivial quantum behavior, and showed that it can capture the correct quantum dynamical features. PMID:20001028

  19. The Effect of Geographical Scale of Sampling on DNA Barcoding

    PubMed Central

    Bergsten, Johannes; Bilton, David T.; Fujisawa, Tomochika; Elliott, Miranda; Monaghan, Michael T.; Balke, Michael; Hendrich, Lars; Geijer, Joja; Herrmann, Jan; Foster, Garth N.; Ribera, Ignacio; Nilsson, Anders N.; Barraclough, Timothy G.; Vogler, Alfried P.

    2012-01-01

    Eight years after DNA barcoding was formally proposed on a large scale, CO1 sequences are rapidly accumulating from around the world. While studies to date have mostly targeted local or regional species assemblages, the recent launch of the global iBOL project (International Barcode of Life), highlights the need to understand the effects of geographical scale on Barcoding's goals. Sampling has been central in the debate on DNA Barcoding, but the effect of the geographical scale of sampling has not yet been thoroughly and explicitly tested with empirical data. Here, we present a CO1 data set of aquatic predaceous diving beetles of the tribe Agabini, sampled throughout Europe, and use it to investigate how the geographic scale of sampling affects 1) the estimated intraspecific variation of species, 2) the genetic distance to the most closely related heterospecific, 3) the ratio of intraspecific and interspecific variation, 4) the frequency of taxonomically recognized species found to be monophyletic, and 5) query identification performance based on 6 different species assignment methods. Intraspecific variation was significantly correlated with the geographical scale of sampling (R-square = 0.7), and more than half of the species with 10 or more sampled individuals (N = 29) showed higher intraspecific variation than 1% sequence divergence. In contrast, the distance to the closest heterospecific showed a significant decrease with increasing geographical scale of sampling. The average genetic distance dropped from > 7% for samples within 1 km, to < 3.5% for samples up to > 6000 km apart. Over a third of the species were not monophyletic, and the proportion increased through locally, nationally, regionally, and continentally restricted subsets of the data. The success of identifying queries decreased with increasing spatial scale of sampling; liberal methods declined from 100% to around 90%, whereas strict methods dropped to below 50% at continental scales. The

  20. Effective dose scaling factors for use with cascade impactor sampling data in tenorm inhalation exposures.

    PubMed

    Kim, Kwang Pyo; Wu, Chang-Yu; Birky, Brian K; Bolch, Wesley E

    2005-10-01

    When assessing the effective dose to workers following radio-aerosol inhalation exposures, significant reductions in dose uncertainty can be achieved through direct measurement of the particle-size distribution. The University of Washington Mark III cascade impactor is one such air sampling device that permits the user to determine aerosol mass and radioactivity concentrations as a function of particle size within eight different size intervals (each corresponding to a different impactor stage or end filter). Traditionally, dose assessments made using the LUDEP code or other internal dosimetry software utilize this air sampling information by assigning the radioactivity measured at each stage as concentrated at a single representative size central to the size interval. In this study, we explore more realistic assumptions that the measured radioactivity distributes uniformly, linearly increases, or linearly decreases across the particle size interval for each impactor stage. The concept of an effective dose scaling factor, SF(E), is thus introduced whereby (1) the former approach can be used (which requires less computational effort using the LUDEP code), and (2) the resulting values of effective dose per stage can then be rescaled to values appropriate to a linear radioactivity distribution per stage. For a majority of (238)U-series radionuclides, particle size ranges, and absorption classes, differences in these two approaches are less than 10%, and thus no corrections in effective dose per particle stage are needed. Significant corrections, however, were noted in select cases. For uniform or linearly decreasing radioactivity distributions, end-filter particles (0.03 to 0.35 microm) of type F, M, or S radionuclides were assigned values of SF(E) ranging from 1.15 to 1.44, while 3(rd) stage particles (4.5 to 12 microm) of type M and S radionuclides were assigned values of SF(E) ranging from 1.11 to 1.53. When the cascade impactor measurements indicate a linear

  1. The effect of intense interval cycle-training on unloading-induced dysfunction and atrophy in the human calf muscle.

    PubMed

    Hotta, Norio; Ishida, Koji; Sato, Kohei; Koike, Teruhiko; Katayama, Keisho; Akima, Hiroshi

    2011-01-01

    We investigated whether intense interval training on a cycle ergometer would prevent loss of muscle strength and atrophy in the human calf during unilateral lower limb suspension (ULLS). The present study involved 11 healthy men. We defined unloading leg and contralateral leg as ULLS-leg and CONT-leg, respectively. The subjects were divided into 2 groups: one with single-leg cycling training (Tr-UL, n=6); the other as a control (UL, n=5). The Tr-UL group performed an intense 25-min interval cycling training up to 80% of peak oxygen uptake on alternate days during 20-d ULLS. It was found that: 1) in maximal voluntary contraction (MVC) and the cross-sectional area of the planter flexor, there was a significant time- (pre-ULLS and post-ULLS) by-leg (ULLS-leg and CONT-leg) interaction; 2) in voluntary activation during MVC evaluated by the twitch interpolation technique, no significant time-by-leg interaction was detected but the trend of change from before to after ULLS tended to be different between ULLS-leg and CONT-leg; and 3) regarding ULLS-leg, the change in any parameters was not significantly different between the Tr-UL and UL groups. These results suggest that unloading induces dysfunction and atrophy in the human calf and that high-intensity interval training on a cycle ergometer cannot significantly prevent unloading-induced deconditioning in the human calf.

  2. Effect of High Intensity Interval and Continuous Swimming Training on Body Mass Adiposity Level and Serum Parameters in High-Fat Diet Fed Rats.

    PubMed

    da Rocha, Guilherme L; Crisp, Alex H; de Oliveira, Maria R M; da Silva, Carlos A; Silva, Jadson O; Duarte, Ana C G O; Sene-Fiorese, Marcela; Verlengia, Rozangela

    2016-01-01

    This study aimed to investigate the effects of interval and continuous training on the body mass gain and adiposity levels of rats fed a high-fat diet. Forty-eight male Sprague-Dawley rats were randomly divided into two groups, standard diet and high-fat diet, and received their respective diets for a period of four weeks without exercise stimuli. After this period, the animals were randomly divided into six groups (n = 8): control standard diet (CS), control high-fat diet (CH), continuous training standard diet (CTS), continuous training high-fat diet (CTH), interval training standard diet (ITS), and interval training high-fat diet (ITH). The interval and continuous training consisted of a swimming exercise performed over eight weeks. CH rats had greater body mass gain, sum of adipose tissues mass, and lower serum high density lipoprotein values than CS. The trained groups showed lower values of feed intake, caloric intake, body mass gain, and adiposity levels compared with the CH group. No significant differences were observed between the trained groups (CTS versus ITS and CTH versus ITH) on body mass gains and adiposity levels. In conclusion, both training methodologies were shown to be effective in controlling body mass gain and adiposity levels in high-fat diet fed rats. PMID:26904718

  3. Effect of High Intensity Interval and Continuous Swimming Training on Body Mass Adiposity Level and Serum Parameters in High-Fat Diet Fed Rats

    PubMed Central

    da Rocha, Guilherme L.; Crisp, Alex H.; de Oliveira, Maria R. M.; da Silva, Carlos A.; Silva, Jadson O.; Duarte, Ana C. G. O.; Sene-Fiorese, Marcela; Verlengia, Rozangela

    2016-01-01

    This study aimed to investigate the effects of interval and continuous training on the body mass gain and adiposity levels of rats fed a high-fat diet. Forty-eight male Sprague-Dawley rats were randomly divided into two groups, standard diet and high-fat diet, and received their respective diets for a period of four weeks without exercise stimuli. After this period, the animals were randomly divided into six groups (n = 8): control standard diet (CS), control high-fat diet (CH), continuous training standard diet (CTS), continuous training high-fat diet (CTH), interval training standard diet (ITS), and interval training high-fat diet (ITH). The interval and continuous training consisted of a swimming exercise performed over eight weeks. CH rats had greater body mass gain, sum of adipose tissues mass, and lower serum high density lipoprotein values than CS. The trained groups showed lower values of feed intake, caloric intake, body mass gain, and adiposity levels compared with the CH group. No significant differences were observed between the trained groups (CTS versus ITS and CTH versus ITH) on body mass gains and adiposity levels. In conclusion, both training methodologies were shown to be effective in controlling body mass gain and adiposity levels in high-fat diet fed rats. PMID:26904718

  4. Electroosmosis effect on micro permeability through rock samples

    SciTech Connect

    Touchard G.; Paillat, T.; Beaufort, D.; Watanabe, S.

    1996-01-24

    It is a well known fact that a liquid flowing through a microporous media creates a potential difference between entry and exit of the sample. This phenomenon is known as streaming potential. In an other hand, when a potential difference is applied through an impregnate rock sample, a flow is induced, this is called electroosmosis effect. In this paper, we examine electroosmosis experiments made in a percolation cell in which two gold electrodes are placed in the inner and in the outer chamber. The temperature, the pressure and potential difference, the flow, the current and the chemical composition of water in chambers may be recorded. Experiment consist to the application of electric field through the sample and to observe the evolution of the flow, the electrical current and the chemical dissolution.

  5. Effects of within-Class Differences in Sample Responding on Acquired Sample Equivalence

    ERIC Educational Resources Information Center

    Urcuioli, Peter J.; Vasconcelos, Maarco

    2008-01-01

    Two experiments examined whether acquired sample equivalence in many-to-one matching was affected by variation in sample-response requirements. In each experiment, pigeons responded on either identical or different response schedules to the sample stimuli that occasioned the same reinforced comparison choice (i.e., to the within-class samples).…

  6. Effects of spatial scale of sampling on food web structure

    PubMed Central

    Wood, Spencer A; Russell, Roly; Hanson, Dieta; Williams, Richard J; Dunne, Jennifer A

    2015-01-01

    This study asks whether the spatial scale of sampling alters structural properties of food webs and whether any differences are attributable to changes in species richness and connectance with scale. Understanding how different aspects of sampling effort affect ecological network structure is important for both fundamental ecological knowledge and the application of network analysis in conservation and management. Using a highly resolved food web for the marine intertidal ecosystem of the Sanak Archipelago in the Eastern Aleutian Islands, Alaska, we assess how commonly studied properties of network structure differ for 281 versions of the food web sampled at five levels of spatial scale representing six orders of magnitude in area spread across the archipelago. Species (S) and link (L) richness both increased by approximately one order of magnitude across the five spatial scales. Links per species (L/S) more than doubled, while connectance (C) decreased by approximately two-thirds. Fourteen commonly studied properties of network structure varied systematically with spatial scale of sampling, some increasing and others decreasing. While ecological network properties varied systematically with sampling extent, analyses using the niche model and a power-law scaling relationship indicate that for many properties, this apparent sensitivity is attributable to the increasing S and decreasing C of webs with increasing spatial scale. As long as effects of S and C are accounted for, areal sampling bias does not have a special impact on our understanding of many aspects of network structure. However, attention does need be paid to some properties such as the fraction of species in loops, which increases more than expected with greater spatial scales of sampling. PMID:26380704

  7. Effects of High Intensity Interval Training and Strength Training on Metabolic, Cardiovascular and Hormonal Outcomes in Women with Polycystic Ovary Syndrome: A Pilot Study

    PubMed Central

    Almenning, Ida; Rieber-Mohn, Astrid; Lundgren, Kari Margrethe; Shetelig Løvvik, Tone; Garnæs, Kirsti Krohn; Moholdt, Trine

    2015-01-01

    Background Polycystic ovary syndrome is a common endocrinopathy in reproductive-age women, and associates with insulin resistance. Exercise is advocated in this disorder, but little knowledge exists on the optimal exercise regimes. We assessed the effects of high intensity interval training and strength training on metabolic, cardiovascular, and hormonal outcomes in women with polycystic ovary syndrome. Materials and Methods Three-arm parallel randomized controlled trial. Thirty-one women with polycystic ovary syndrome (age 27.2 ± 5.5 years; body mass index 26.7 ± 6.0 kg/m2) were randomly assigned to high intensity interval training, strength training, or a control group. The exercise groups exercised three times weekly for 10 weeks. Results The main outcome measure was change in homeostatic assessment of insulin resistance (HOMA-IR). HOMA-IR improved significantly only after high intensity interval training, by -0.83 (95% confidence interval [CI], -1.45, -0.20), equal to 17%, with between-group difference (p = 0.014). After high intensity interval training, high-density lipoprotein cholesterol increased by 0.2 (95% CI, 0.02, 0.5) mmol/L, with between group difference (p = 0.04). Endothelial function, measured as flow-mediated dilatation of the brachial artery, increased significantly after high intensity interval training, by 2.0 (95% CI, 0.1, 4.0) %, between-group difference (p = 0.08). Fat percentage decreased significantly after both exercise regimes, without changes in body weight. After strength training, anti-Müllarian hormone was significantly reduced, by -14.8 (95% CI, -21.2, -8.4) pmol/L, between-group difference (p = 0.04). There were no significant changes in high-sensitivity C-reactive protein, adiponectin or leptin in any group. Conclusions High intensity interval training for ten weeks improved insulin resistance, without weight loss, in women with polycystic ovary syndrome. Body composition improved significantly after both strength training and

  8. Effect of temporal sampling and timing for soil moisture measurements at field scale

    NASA Astrophysics Data System (ADS)

    Snapir, B.; Hobbs, S.

    2012-04-01

    Estimating soil moisture at field scale is valuable for various applications such as irrigation scheduling in cultivated watersheds, flood and drought prediction, waterborne disease spread assessment, or even determination of mobility with lightweight vehicles. Synthetic aperture radar on satellites in low Earth orbit can provide fine resolution images with a repeat time of a few days. For an Earth observing satellite, the choice of the orbit is driven in particular by the frequency of measurements required to meet a certain accuracy in retrieving the parameters of interest. For a given target, having only one image every week may not enable to capture the full dynamic range of soil moisture - soil moisture can change significantly within a day when rainfall occurs. Hence this study focuses on the effect of temporal sampling and timing of measurements in terms of error on the retrieved signal. All the analyses are based on in situ measurements of soil moisture (acquired every 30 min) from the OzNet Hydrological Monitoring Network in Australia for different fields over several years. The first study concerns sampling frequency. Measurements at different frequencies were simulated by sub-sampling the original data. Linear interpolation was used to estimate the missing intermediate values, and then this time series was compared to the original. The difference between these two signals is computed for different levels of sub-sampling. Results show that the error increases linearly when the interval is less than 1 day. For intervals longer than a day, a sinusoidal component appears on top of the linear growth due to the diurnal variation of surface soil moisture. Thus, for example, the error with measurements every 4.5 days can be slightly less than the error with measurements every 2 days. Next, for a given sampling interval, this study evaluated the effect of the time during the day at which measurements are made. Of course when measurements are very frequent the time

  9. Effects of Mesh Size on Sieved Samples of Corophium volutator

    NASA Astrophysics Data System (ADS)

    Crewe, Tara L.; Hamilton, Diana J.; Diamond, Antony W.

    2001-08-01

    Corophium volutator (Pallas), gammaridean amphipods found on intertidal mudflats, are frequently collected in mud samples sieved on mesh screens. However, mesh sizes used vary greatly among studies, raising the possibility that sampling methods bias results. The effect of using different mesh sizes on the resulting size-frequency distributions of Corophium was tested by collecting Corophium from mud samples with 0·5 and 0·25 mm sieves. More than 90% of Corophium less than 2 mm long passed through the larger sieve. A significantly smaller, but still substantial, proportion of 2-2·9 mm Corophium (30%) was also lost. Larger size classes were unaffected by mesh size. Mesh size significantly changed the observed size-frequency distribution of Corophium, and effects varied with sampling date. It is concluded that a 0·5 mm sieve is suitable for studies concentrating on adults, but to accurately estimate Corophium density and size-frequency distributions, a 0·25 mm sieve must be used.

  10. Pilot opinions of sampling effects in lateral-directional control

    NASA Technical Reports Server (NTRS)

    Stengel, R. F.; Miller, G. E.

    1982-01-01

    Flight experiments with a microprocessor control system were conducted to determine the effects of variations in sampling parameters on several pilots' opinions of lateral-directional flying qualities. Princeton's variable-response research aircraft (VRA), which is equipped with a microprocessor based digital flight control system (Micro-DFCS), was the test vehicle. Two U.S. Navy pilots evaluated the effects of sampling rate, quantization, and pure time delay during tracking, approach, and landing. Aircraft carrier approach tasks were conducted using a Navy approach mirror. Acquisition and tracking of fixed objects on the ground provided additional information related to the Navy misson. The longitudinal controls were implemented with analog electronics, while the lateral-directional pilot inputs (stick and rudder) were fed to the Micro-DFCS, which commanded the ailerons and rudder. The conceptual relationship between the evaluation pilot's lateral-directional inputs, the flight computer, and the aircraft are illustrated.

  11. Effects of hydrophilic hydrocolloids on dough and bread performance of samples made from frozen doughs.

    PubMed

    Dodić, J; Pejin, D; Dodić, S; Popov, S; Mastilović, J; Popov-Raljić, J; Zivanovic, S

    2007-05-01

    The objective of this study was to determine the effects of hydrocolloids in dough (xanthan 0.02%, 0.06%, and 0.1%; kappa-carrageenan and carboxymethylcellulose 0.2%, 0.6%, and 1.0%) and duration of frozen storage on the quality of finished bakery product. Doughs were prepared with different concentrations of gums, stored at -18 degrees C and analyzed after 0, 7, 14, and 30 d for fermentation activity of yeast and rising time of dough. At the end of each frozen storage interval, bread was prepared and characterized for specific volume, crumb firmness, and crumb structure. The addition of the gums had significant effects on dough performance and quality of the final product. Gums at all tested concentrations reduced fermentation activity of yeast and prolonged the rising time of dough, which was similar to the effects of frozen storage. However, specific volume of bread for the control sample significantly decreased on the 30th d of frozen storage. Addition of hydrocolloids resulted in higher specific volume of loaves compared to the specific volume of control sample loaves. With the increase of the duration of frozen storage the specific volume of bread decreases in all analyzed samples. This decrease is less in the samples with hydrocolloids compared to the decrease in the control sample. The addition of 0.1% xanthan accomplished the same or higher values for specific fermentation activity, specific volume, and penetrometric's number compared to the values accomplished by the addition of 1% carboxymethylcellulose and kappa-carrageenan, respectively. PMID:17995784

  12. Effects of hydrophilic hydrocolloids on dough and bread performance of samples made from frozen doughs.

    PubMed

    Dodić, J; Pejin, D; Dodić, S; Popov, S; Mastilović, J; Popov-Raljić, J; Zivanovic, S

    2007-05-01

    The objective of this study was to determine the effects of hydrocolloids in dough (xanthan 0.02%, 0.06%, and 0.1%; kappa-carrageenan and carboxymethylcellulose 0.2%, 0.6%, and 1.0%) and duration of frozen storage on the quality of finished bakery product. Doughs were prepared with different concentrations of gums, stored at -18 degrees C and analyzed after 0, 7, 14, and 30 d for fermentation activity of yeast and rising time of dough. At the end of each frozen storage interval, bread was prepared and characterized for specific volume, crumb firmness, and crumb structure. The addition of the gums had significant effects on dough performance and quality of the final product. Gums at all tested concentrations reduced fermentation activity of yeast and prolonged the rising time of dough, which was similar to the effects of frozen storage. However, specific volume of bread for the control sample significantly decreased on the 30th d of frozen storage. Addition of hydrocolloids resulted in higher specific volume of loaves compared to the specific volume of control sample loaves. With the increase of the duration of frozen storage the specific volume of bread decreases in all analyzed samples. This decrease is less in the samples with hydrocolloids compared to the decrease in the control sample. The addition of 0.1% xanthan accomplished the same or higher values for specific fermentation activity, specific volume, and penetrometric's number compared to the values accomplished by the addition of 1% carboxymethylcellulose and kappa-carrageenan, respectively.

  13. The effects of sampling frequency on the climate statistics of the ECMWF general circulation model

    SciTech Connect

    Phillips, T.J.; Gates, W.L.; Arpe, K.

    1992-09-01

    The effects of sampling frequency on the first- and second-moment statistics of selected EC model variables are investigated in a simulation of ``perpetual July`` with a diurnal cycle included and with surface and atmospheric fields saved at hourly intervals. The shortest characteristic time scales (as determined by the enfolding time of lagged autocorrelation functions) are those of ground heat fluxes and temperatures, precipitation and run-off, convective processes, cloud properties, and atmospheric vertical motion, while the longest time scales are exhibited by soil temperature and moisture, surface pressure, and atmospheric specific humidity, temperature and wind. The time scales of surface heat and momentum fluxes and of convective processes are substantially shorter over land than over the oceans.

  14. The effects of sampling frequency on the climate statistics of the ECMWF general circulation model

    SciTech Connect

    Phillips, T.J.; Gates, W.L. ); Arpe, K. )

    1992-09-01

    The effects of sampling frequency on the first- and second-moment statistics of selected EC model variables are investigated in a simulation of perpetual July'' with a diurnal cycle included and with surface and atmospheric fields saved at hourly intervals. The shortest characteristic time scales (as determined by the enfolding time of lagged autocorrelation functions) are those of ground heat fluxes and temperatures, precipitation and run-off, convective processes, cloud properties, and atmospheric vertical motion, while the longest time scales are exhibited by soil temperature and moisture, surface pressure, and atmospheric specific humidity, temperature and wind. The time scales of surface heat and momentum fluxes and of convective processes are substantially shorter over land than over the oceans.

  15. Effects of flow speed and circulation interval on water quality and zooplankton in a pond-ditch circulation system.

    PubMed

    Ma, Lin; He, Feng; Sun, Jian; Huang, Tao; Xu, Dong; Zhang, Yi; Wu, Zhenbin

    2015-07-01

    A pond-ditch circulation system (PDCS) shows great promises for ecological restoration of rural contaminated water in southern China. In this study, the optimal flow speed, circulation interval, and their combination for the system were investigated for higher pollutant removal efficiency and lower costs in three separate experiments: I, II, and III, respectively. In each experiment, there are three PDCSs (S1, S2, and S3) with different water circulation speeds or circulation intervals, respectively. The results demonstrated that in experiment I, total nitrogen (TN) removal rates, species numbers, and diversity indexes of zooplankton in S1 with a flow speed of 3.6 L/h were significantly higher than those in S2 (7.2 L/h) and S3 (10.2 L/h), respectively. Similarly, in experiment II, S3 circulating every other 4 h had significantly higher TN reduction rates, species numbers, and diversity indexes than S1 and S2 circulating every other 1 and 2 h, respectively. In experiment III, water qualities in S1 (circulation of 3.6 L/h + interval of 4 h) were better than those in S2 (7.2 L/h + 4 h) and S3 (10.2 L/h + 6 h), respectively. Together, circulation at every other 4 h (3.6 L/h) is probably the optimal operating condition for the PDCS in remediating rural contaminated water. PMID:25693828

  16. Effect of essential fatty acid and zinc supplementation during pregnancy on birth intervals, neonatal piglet brain myelination, stillbirth, and preweaning mortality.

    PubMed

    Vallet, J L; Rempel, L A; Miles, J R; Webel, S K

    2014-06-01

    Omega fatty acids and zinc contribute to physiological pathways that could affect the farrowing process, stillbirth, preweaning mortality, and postweaning return to estrus. To determine effects of omega fatty acids and zinc on these reproductive traits, gilts were mated and fed either a control diet, a diet supplemented with 1.09% Gromega, a diet supplemented with 0.07% zinc sulfate, or a diet supplemented with both Gromega and zinc sulfate from d 80 of gestation until farrowing. Farrowings were video recorded to obtain birth intervals for each piglet, and the number of live and stillborn piglets was recorded. On d 1 after farrowing, piglets were weighed, and the smallest piglet in each litter was sacrificed. A blood sample was collected to measure the immunoglobulin immunocrit ratio, and brain, cerebellum, brain stem, full and empty stomach (to calculate stomach content weight), and heart weights were recorded. Because myelination of specific brain regions may affect preweaning mortality, brain stem, cerebellum, and spinal cord tissues were measured for content of myelin basic proteins and myelin lipids. For remaining piglets, survival to weaning and weaning weights were recorded. Results indicated a weak positive correlation (r = 0.23, P < 0.05) between immunocrit values and brain stem high molecular weight myelin basic protein. There was also a Gromega × zinc supplementation interaction (P < 0.05) on brain stem high molecular weight myelin basic protein in which the combined treatment was greater than the control or each supplement alone. Zinc treatment decreased stillbirth rate during prolonged farrowing and subsequent preweaning survival of low birth weight piglets. Gromega increased overall stillbirth rate and increased the stillbirth rate during prolonged farrowing. There were no relationships between myelin measurements and preweaning survival. In conclusion, combined Gromega and zinc supplementation appeared to improve myelination, but zinc alone improved

  17. The effects of sampling frequency on the climate statistics of the European Centre for Medium-Range Weather Forecasts

    SciTech Connect

    Phillips, T.J.; Gates, W.L. ); Arpe, K. )

    1992-12-20

    The effects of sampling frequency on the first- and second-moment statistics of selected European Centre for Medium-Range Weather Forecasts (ECMWF) model variables are investigated in a simulation of perpetual July' with a diurnal cycle included and with surface and atmospheric fields saved at hourly intervals. The shortest characteristic time scales are those of ground heat fluxes and temperatures, precipitation and runoff, convective processes, cloud properties, and atmospheric vertical motion, while the longest time scales are exhibited by soil temperature and moisture, surface pressure, and atmospheric specific humidity, temperature, and wind. The time scales of surface heat and momentum fluxes and of convective processes are substantially shorter over land than over oceans. An appropriate sampling frequency for each model variable is obtained by comparing the estimates of first- and second-moment statistics determined at intervals ranging from 2 to 24 hours with the best' estimates obtained from hourly sampling. Relatively accurate estimation of first- and second-moment climate statistics can be achieved by sampling a model variable at intervals that usually are longer than the bandwidth of its time series but that often are shorter than its characteristic time scale. The superior estimates of first-moment statistics are accompanied by inferior estimates of the variance of the daily means due to the presence of systematic biases, but these probably can be avoided by defining a different measure of low-frequency variability. Estimates of the intradiurnal variance of accumulated precipitation and surface runoff also are strongly impacted by the length of the storage interval. In light of these results, several alternative strategies for storage of the EMWF model variables are recommended. 20 refs., 9 figs., 1 tab.

  18. A pilot study examining the effects of low-volume high-intensity interval training and continuous low to moderate intensity training on quality of life, functional capacity and cardiovascular risk factors in cancer survivors

    PubMed Central

    Pumpa, Kate L.; Arnolda, Leonard; Cooke, Julie; Yip, Desmond; Craft, Paul S.; Semple, Stuart

    2016-01-01

    Purpose The aim of this study was to evaluate the effects of low-volume high-intensity interval training and continuous low to moderate intensity training on quality of life, functional capacity and cardiovascular disease risk factors in cancer survivors. Methods Cancer survivors within 24 months post-diagnosis were randomly assigned into the low-volume high-intensity interval training group (n = 8) or the continuous low to moderate intensity training group (n = 8) group for 36 sessions (12 weeks) of supervised exercise. The low-volume high-intensity interval training (LVHIIT) group performed 7 × 30 s intervals (≥85% maximal heart rate) and the continuous low to moderate intensity training (CLMIT) group performed continuous aerobic training for 20 min (≤55% maximal heart rate) on a stationary bike or treadmill. Results Significant improvements (time) were observed for 13 of the 23 dependent variables (ES 0.05–0.61, p ≤ 0.05). An interaction effect was observed for six minute walk test (18.53% [32.43–4.63] ES 0.50, p ≤ 0.01) with the LVHIIT group demonstrating greater improvements. Conclusion These preliminary findings suggest that both interventions can induce improvements in quality of life, functional capacity and selected cardiovascular disease risk factors. The LVHIIT program was well tolerated by the participants and our results suggest that LVHIIT is the preferred modality to improve fitness (6MWT); it remains to be seen which intervention elicits the most clinically relevant outcomes for patients. A larger sample size with a control group is required to confirm the significance of these findings. PMID:27781180

  19. Effect of sintering temperature and time intervals on morphological and hardness behaviour of Al-20 vol% Sn matrix composites

    NASA Astrophysics Data System (ADS)

    Badarulzaman, N. A.; Karim, S. R.; Lajis, M. A.

    2015-05-01

    Aluminium (Al) alloys are widely used in various industries, such as automotive and aerospace. The production processes in these sectors create large amount of Al residues. In this paper, a new method of recycling Al chip is presented. Metal matrix composite (MMCs) of Al-20 vol% Sn was prepared by using solid state direct conversion method of recycled Al 6061 alloy. Constant pressure (10 ton) was used to implement the cold forging process. The differences of sintering temperature (200 °C, 250 °C, 300 °C and 350 °C) and time intervals (1h, 2h, 3h, 4h and 5h) were studied to obtain the optimum hardness, strength and surface integrity of Al-20 vol% Sn. The results showed that, hardness and strength of Al-20 vol% Sn was decreased by additional temperature and increase with time interval of sintering. Sintering temperature at 350 °C produces better morphology structure of Al-Sn composites.

  20. Storage Effects on Sample Integrity of Environmental Surface Sampling Specimens with Bacillus anthracis Spores

    PubMed Central

    Perry, K. Allison; O’Connell, Heather A.; Rose, Laura J.; Noble-Wang, Judith A.; Arduino, Matthew J.

    2016-01-01

    The effect of packaging, shipping temperatures and storage times on recovery of Bacillus anthracis. Sterne spores from swabs was investigated. Macrofoam swabs were pre-moistened, inoculated with Bacillus anthracis spores, and packaged in primary containment or secondary containment before storage at −15°C, 5°C, 21°C, or 35°C for 0–7 days. Swabs were processed according to validated Centers for Disease Control/Laboratory Response Network culture protocols, and the percent recovery relative to a reference sample (T0) was determined for each variable. No differences were observed in recovery between swabs held at −15° and 5°C, (p ≥ 0.23). These two temperatures provided significantly better recovery than swabs held at 21°C or 35°C (all 7 days pooled, p ≤ 0.04). The percent recovery at 5°C was not significantly different if processed on days 1, 2 or 4, but was significantly lower on day 7 (day 2 vs. 7, 5°C, 102, p=0.03). Secondary containment provided significantly better percent recovery than primary containment, regardless of storage time (5°C data, p ≤ 0.008). The integrity of environmental swab samples containing Bacillus anthracis spores shipped in secondary containment was maintained when stored at −15°C or 5°C and processed within 4 days to yield the optimum percent recovery of spores. PMID:27213119

  1. Investigating the effect of modeling single-vehicle and multi-vehicle crashes separately on confidence intervals of Poisson-gamma models.

    PubMed

    Geedipally, Srinivas Reddy; Lord, Dominique

    2010-07-01

    Crash prediction models still constitute one of the primary tools for estimating traffic safety. These statistical models play a vital role in various types of safety studies. With a few exceptions, they have often been employed to estimate the number of crashes per unit of time for an entire highway segment or intersection, without distinguishing the influence different sub-groups have on crash risk. The two most important sub-groups that have been identified in the literature are single- and multi-vehicle crashes. Recently, some researchers have noted that developing two distinct models for these two categories of crashes provides better predicting performance than developing models combining both crash categories together. Thus, there is a need to determine whether a significant difference exists for the computation of confidence intervals when a single model is applied rather than two distinct models for single- and multi-vehicle crashes. Building confidence intervals have many important applications in highway safety. This paper investigates the effect of modeling single- and multi-vehicle (head-on and rear-end only) crashes separately versus modeling them together on the prediction of confidence intervals of Poisson-gamma models. Confidence intervals were calculated for total (all severities) crash models and fatal and severe injury crash models. The data used for the comparison analysis were collected on Texas multilane undivided highways for the years 1997-2001. This study shows that modeling single- and multi-vehicle crashes separately predicts larger confidence intervals than modeling them together as a single model. This difference is much larger for fatal and injury crash models than for models for all severity levels. Furthermore, it is found that the single- and multi-vehicle crashes are not independent. Thus, a joint (bivariate) model which accounts for correlation between single- and multi-vehicle crashes is developed and it predicts wider

  2. Exploring the effect of drought extent and interval on the Florida snail kite: Interplay between spatial and temporal scales

    USGS Publications Warehouse

    Mooij, Wolf M.; Bennetts, Robert E.; Kitchens, Wiley M.; DeAngelis, Donald L.

    2002-01-01

    The paper aims at exploring the viability of the Florida snail kite population under various drought regimes in its wetland habitat. The population dynamics of snail kites are strongly linked with the hydrology of the system due to the dependence of this bird species on one exclusive prey species, the apple snail, which is negatively affected by a drying out of habitat. Based on empirical evidence, it has been hypothesised that the viability of the snail kite population critically depends not only on the time interval between droughts, but also on the spatial extent of these droughts. A system wide drought is likely to result in reduced reproduction and increased mortality, whereas the birds can respond to local droughts by moving to sites where conditions are still favourable. This paper explores the implications of this hypothesis by means of a spatially-explicit individual-based model. The specific aim of the model is to study in a factorial design the dynamics of the kite population in relation to two scale parameters, the temporal interval between droughts and the spatial correlation between droughts. In the model high drought frequencies led to reduced numbers of kites. Also, habitat degradation due to prolonged periods of inundation led to lower predicted numbers of kites. Another main result was that when the spatial correlation between droughts was low, the model showed little variability in the predicted numbers of kites. But when droughts occurred mostly on a system wide level, environmental stochasticity strongly increased the stochasticity in kite numbers and in the worst case the viability of the kite population was seriously threatened.

  3. Acute and chronic effect of sprint interval training combined with postexercise blood-flow restriction in trained individuals.

    PubMed

    Taylor, Conor W; Ingham, Stephen A; Ferguson, Richard A

    2016-01-01

    This investigation assessed the efficacy of sprint interval training (SIT) combined with postexercise blood-flow restriction as a novel approach to enhance maximal aerobic physiology and performance. In study 1, a between-groups design was used to determine whether 4 weeks (2 days per week) of SIT (repeated 30 s maximal sprint cycling) combined with postexercise blood-flow restriction (BFR) enhanced maximal oxygen uptake (V̇(O2max)) and 15 km cycling time-trial performance (15 km TT) compared with SIT alone (CON) in trained individuals. The V̇(O2max) increased after BFR by 4.5% (P = 0.01) but was unchanged after CON. There was no difference in 15 km TT performance after CON or BFR. In study 2, using a repeated-measures design, participants performed an acute bout of either BFR or CON. Muscle biopsies were taken before and after exercise to examine the activation of signalling pathways regulating angiogenesis and mitochondrial biogenesis. Phosphorylation of p38MAPK(Thr180/Tyr182) increased by a similar extent after CON and BFR. There was no difference in the magnitude of increase in PGC-1α, VEGF and VEGFR-2 mRNA expression between protocols; however, HIF-1α mRNA expression increased (P = 0.04) at 3 h only after BFR. We have demonstrated the potency of combining BFR with SIT in increasing V̇(O2max) in trained individuals, but this did not translate to an enhanced exercise performance. Sprint interval training alone did not induce any observable adaptation. Although the mechanisms are not fully understood, we present preliminary evidence that BFR leads to enhanced HIF-1α-mediated cell signalling.

  4. Phase chemistry, structure, and radiation effects in lunar samples.

    PubMed

    Arrhenius, G; Asunmaa, S; Drever, J I; Everson, J; Fitzgerald, R W; Frazer, J Z; Fujita, H; Hanor, J S; Lal, D; Liang, S S; Macdougall, D; Reid, A M; Sinkankas, J; Wilkening, L

    1970-01-30

    Phase chemistry, structure, and radiation effects were studied in rock, breccia, and soil samples. The regolith apparently developed in the final stages of accretion and was modified by later impact processes and radiation weathering. Exposure ages indicate transfer of buried igneous rock fragments to the near surface late in lunar history. With a few exceptions igneous rock fragments, soil, and breccia share the same distinctive chemistry, probably acquired before accretion of the moon. The igneous rocks texturally resemble basaltic achondrites, and the soil and breccias contain glassy spheres analogous to chondrules.

  5. Effects of sample size on KERNEL home range estimates

    USGS Publications Warehouse

    Seaman, D.E.; Millspaugh, J.J.; Kernohan, Brian J.; Brundige, Gary C.; Raedeke, Kenneth J.; Gitzen, Robert A.

    1999-01-01

    Kernel methods for estimating home range are being used increasingly in wildlife research, but the effect of sample size on their accuracy is not known. We used computer simulations of 10-200 points/home range and compared accuracy of home range estimates produced by fixed and adaptive kernels with the reference (REF) and least-squares cross-validation (LSCV) methods for determining the amount of smoothing. Simulated home ranges varied from simple to complex shapes created by mixing bivariate normal distributions. We used the size of the 95% home range area and the relative mean squared error of the surface fit to assess the accuracy of the kernel home range estimates. For both measures, the bias and variance approached an asymptote at about 50 observations/home range. The fixed kernel with smoothing selected by LSCV provided the least-biased estimates of the 95% home range area. All kernel methods produced similar surface fit for most simulations, but the fixed kernel with LSCV had the lowest frequency and magnitude of very poor estimates. We reviewed 101 papers published in The Journal of Wildlife Management (JWM) between 1980 and 1997 that estimated animal home ranges. A minority of these papers used nonparametric utilization distribution (UD) estimators, and most did not adequately report sample sizes. We recommend that home range studies using kernel estimates use LSCV to determine the amount of smoothing, obtain a minimum of 30 observations per animal (but preferably a?Y50), and report sample sizes in published results.

  6. Orientation Errors in Paleomagnetic Core Samples and Their Effects

    NASA Astrophysics Data System (ADS)

    Kono, M.

    2011-12-01

    In paleomagnetic studies, samples are often obtained as cylindrical cores by the use of engine drills. Two angles measured for the core in the field (the angle P between cylindrical axis and the horizontal plane, and the angle A between a horizontal direction in the core and the true north) are needed to describe the direction of magnetic remanence in geographic coordinates. These angles can be measured with an error of about 1 degree or less. The error in paleomagnetic directions are usually given by Fisher's semi-angle of 95% confidence (α 95), which is typically a few to ten degrees. It appears therefore that the orientation errors are negligibly small. However, this it not quite correct. There is no problem about the measurement of P, but the angle in the horizontal plane (A) is often measured by a magnetic compass, which is a source of large errors. In particular, large local magnetic anomalies often accompany volcanic rock terrain because of their strong magnetization. This effect is known quite a long time, but quantitative estimate of orientation errors is not available yet. We have obtained quite a large number of data (182 lavas, 903 samples) from Lundarhals area of Iceland. For more than 200 samples of these, three independent horizontal angles have been measured to estimate A; one by sun's direction, the second by reference to some landmark, and the third is by magnetic direction. Among the rest of samples, more than 600 have reference and magnetic directions. Only 30 samples are determined by magnetic compass alone. From a detailed analysis of these data, the following conclusions were obtained. (1) The difference between sun and reference azimuths are 0.0±0.6~circ (the mean and standard deviation in degrees, for n=203). This is small enough and can be ignored compared to other errors. Consequently, if either of these angles are available, we have almost error-free data for A. (2) The differences between the sun and magnetic azimuths are 0.5±7.8o (n

  7. Effects of 2-, 4- and 12-hour fasting intervals on preoperative gastric fluid pH and volume, and plasma glucose and lipid homeostasis in children.

    PubMed

    Maekawa, N; Mikawa, K; Yaku, H; Nishina, K; Obara, H

    1993-11-01

    We evaluated 105 randomly-selected unpremedicated children aged 1-14 years to determine the effects of a 2-, 4- and 12-h preoperative fasting interval on the preoperative gastric fluid pH and volume, and plasma glucose and lipid homeostasis. Each child undergoing elective surgery ingested a large volume (approximately 10 ml/kg b.w.) of apple juice and then fasted for 2, 4 or 12 h before the estimated induction of anaesthesia. After induction of anaesthesia, gastric fluid was aspirated through a large-bore, multiorifice orogastric tube. Plasma concentrations of glucose, total ketone bodies, non-esterified fatty acid (NEFA), triglycerides, and cortisol were measured at the time of induction to evaluate the fasting interval effects on preoperative plasma glucose and lipid homeostasis. There were no significant differences between the three groups in either gastric fluid volume or pH. In addition, there were no significant differences between the groups with respect to the proportion with a pH < 2.5 and volume > 0.4 ml/kg b.w. Neither plasma concentrations of glucose, triglycerides, nor cortisol at the time of anaesthetic induction differed between the three groups. Both 4 and 12 h nil per os (NPO) caused an increase in lipolysis, which was presumably a compensatory mechanism to maintain normoglycaemia. The plasma NEFA and total ketone bodies concentrations were therefore significantly higher in these two fasting intervals than in 2 h NPO. These data suggest that a 2-h NPO, after a large volume of ingested apple juice, may offer additional benefits by preventing an increase in lipolysis during the fasting interval without either increasing the volume of gastric fluid or decreasing the gastric pH.(ABSTRACT TRUNCATED AT 250 WORDS)

  8. The effect of mare's age on multiple ovulation rate, embryo recovery, post-transfer pregnancy rate, and interovulatory interval in a commercial embryo transfer program in Argentina.

    PubMed

    Marinone, A I; Losinno, L; Fumuso, E; Rodríguez, E M; Redolatti, C; Cantatore, S; Cuervo-Arango, J

    2015-07-01

    Advanced maternal age is an important predisposing factor on the reduction of reproductive efficiency. The aim of this study was to evaluate the effect of donor's age on several reproductive parameters in a commercial equine embryo transfer program. Donors were classified into 3 age groups: Group 1=fillies (3 and 4 years old), Group 2=middle age mares (aged 5-10) and Group 3=old mares (aged 13-25). Embryo recovery, multiple ovulation and pregnancy rates and interovulatory intervals were compared amongst age groups. Group 1 (171/244, 70.1%) and Group 2 (774/1081, 71.6%) had a higher (P<0.005) embryo recovery rate than Group 3 (385/701, 54.9%). Groups 2 and 3 were 2.5 and 3.4 times more likely to have multiple ovulations than Group 1 (P<0.05), respectively. The effect of age group on pregnancy rate was not significant (P>0.05). The interovulatory intervals length was influenced by individual mare (P<0.001), age (P<0.04), Day of flushing (P=0.009) and by month (P<0.012). The overall mean interovulatory interval of Group 1 (16.4±0.17 days) and Group 2 (16.6±0.12 days) was not different (P>0.05), but was shorter than the one of Group 3 (17.4±0.15 days; P<0.04). The embryo recovery rate of flushings from Groups 1 and 2 was influenced by the length of the previous interovulatory interval (P=0.03). PMID:25981675

  9. Effects of interval aerobic training combined with strength exercise on body composition, glycaemic and lipid profile and aerobic capacity of obese rats.

    PubMed

    Coll-Risco, Irene; Aparicio, Virginia A; Nebot, Elena; Camiletti-Moirón, Daniel; Martínez, Rosario; Kapravelou, Garyfallia; López-Jurado, María; Porres, Jesús M; Aranda, Pilar

    2016-08-01

    The purpose of this study was to investigate the effects of interval aerobic training combined with strength exercise in the same training session on body composition, and glycaemic and lipid profile in obese rats. Sixteen lean Zucker rats and sixteen obese Zucker rats were randomly divided into exercise and sedentary subgroups (4 groups, n = 8). Exercise consisted of interval aerobic training combined with strength exercise in the same training session. The animals trained 60 min/day, 5 days/week for 8 weeks. Body composition, lipid and glycaemic profiles and inflammatory markers were assessed. Results showed that fat mass was reduced in both lean and obese rats following the exercise training (effect size (95% confidence interval (CI)) = 1.8 (0.5-3.0)). Plasma low-density lipoprotein-cholesterol and fasting glucose were lower in the exercise compared to the sedentary groups (d = 2.0 (0.7-3.2) and 1.8 (0.5-3.0), respectively). Plasma insulin was reduced in exercise compared to sedentary groups (d = 2.1 (0.8-3.4)). Some exercise × phenotype interactions showed that the highest decreases in insulin, homeostatic model assessment-insulin resistance, fasting and postprandial glucose were observed in the obese + exercise group (all, P < 0.01). The findings of this study suggest that interval aerobic training combined with strength exercise would improve body composition, and lipid and glycaemic profiles, especially in obese rats.

  10. The effect of mare's age on multiple ovulation rate, embryo recovery, post-transfer pregnancy rate, and interovulatory interval in a commercial embryo transfer program in Argentina.

    PubMed

    Marinone, A I; Losinno, L; Fumuso, E; Rodríguez, E M; Redolatti, C; Cantatore, S; Cuervo-Arango, J

    2015-07-01

    Advanced maternal age is an important predisposing factor on the reduction of reproductive efficiency. The aim of this study was to evaluate the effect of donor's age on several reproductive parameters in a commercial equine embryo transfer program. Donors were classified into 3 age groups: Group 1=fillies (3 and 4 years old), Group 2=middle age mares (aged 5-10) and Group 3=old mares (aged 13-25). Embryo recovery, multiple ovulation and pregnancy rates and interovulatory intervals were compared amongst age groups. Group 1 (171/244, 70.1%) and Group 2 (774/1081, 71.6%) had a higher (P<0.005) embryo recovery rate than Group 3 (385/701, 54.9%). Groups 2 and 3 were 2.5 and 3.4 times more likely to have multiple ovulations than Group 1 (P<0.05), respectively. The effect of age group on pregnancy rate was not significant (P>0.05). The interovulatory intervals length was influenced by individual mare (P<0.001), age (P<0.04), Day of flushing (P=0.009) and by month (P<0.012). The overall mean interovulatory interval of Group 1 (16.4±0.17 days) and Group 2 (16.6±0.12 days) was not different (P>0.05), but was shorter than the one of Group 3 (17.4±0.15 days; P<0.04). The embryo recovery rate of flushings from Groups 1 and 2 was influenced by the length of the previous interovulatory interval (P=0.03).

  11. Interactions among resource partitioning, sampling effect, and facilitation on the biodiversity effect: a modeling approach.

    PubMed

    Flombaum, Pedro; Sala, Osvaldo E; Rastetter, Edward B

    2014-02-01

    Resource partitioning, facilitation, and sampling effect are the three mechanisms behind the biodiversity effect, which is depicted usually as the effect of plant-species richness on aboveground net primary production. These mechanisms operate simultaneously but their relative importance and interactions are difficult to unravel experimentally. Thus, niche differentiation and facilitation have been lumped together and separated from the sampling effect. Here, we propose three hypotheses about interactions among the three mechanisms and test them using a simulation model. The model simulated water movement through soil and vegetation, and net primary production mimicking the Patagonian steppe. Using the model, we created grass and shrub monocultures and mixtures, controlled root overlap and grass water-use efficiency (WUE) to simulate gradients of biodiversity, resource partitioning and facilitation. The presence of shrubs facilitated grass growth by increasing its WUE and in turn increased the sampling effect, whereas root overlap (resource partitioning) had, on average, no effect on sampling effect. Interestingly, resource partitioning and facilitation interacted so the effect of facilitation on sampling effect decreased as resource partitioning increased. Sampling effect was enhanced by the difference between the two functional groups in their efficiency in using resources. Morphological and physiological differences make one group outperform the other; once these differences were established further differences did not enhance the sampling effect. In addition, grass WUE and root overlap positively influence the biodiversity effect but showed no interactions.

  12. Effect of nitrogen fertilization rate and regrowth interval of grass herbage on methane emission of zero-grazing lactating dairy cows.

    PubMed

    Warner, D; Podesta, S C; Hatew, B; Klop, G; van Laar, H; Bannink, A; Dijkstra, J

    2015-05-01

    Dairy cattle farming in temperate regions often relies on grass herbage (GH)-based diets but the effect of several grass management options on enteric CH4 emission has not been fully investigated yet. We investigated the combined effect of N fertilization rate and length of regrowth period of GH (predominantly ryegrass) on CH4 emission from lactating dairy cows. In a randomized block design, 28 lactating Holstein-Friesian dairy cows received a basal diet of GH and compound feed [85:15; dry matter (DM) basis]. Treatments consisted of GH cut after 3 or 5 weeks of regrowth, after receiving either a low (20kg of N/ha) or a high (90kg of N/ha) fertilization rate after initial cut. Feed intake, digestibility, milk production and composition, N and energy balance, and CH4 emission were measured during a 5-d period in climate respiration chambers after an adaptation to the diet for 12d. Cows were restricted-fed during measurements and mean DM intake was 15.0±0.16kg/d. Herbage crude protein content varied between 76 and 161g/kg of DM, and sugar content between 186 and 303g/kg of DM. Fat- and protein-corrected milk (FPCM) and feed digestibility increased with increased N fertilization rates and a shorter regrowth interval. Increasing the N fertilization rate increased daily CH4 emission per cow (+10%) and per unit of DM intake (+9%), tended to increase the fraction of gross energy intake emitted as CH4 (+7%), and (partly because of the low crude protein content for the low fertilized GH) only numerically reduced CH4 per unit of FPCM. The longer regrowth interval increased CH4 emission per unit of FPCM (+14%) compared with the shorter regrowth interval, but did not affect CH4 emission expressed in any other unit. With increasing N fertilization CH4 emission decreased per unit of digestible neutral detergent fiber intake (-13%) but not per unit of digestible organic matter intake. There was no interaction of the effect of N fertilization rate and regrowth interval on CH4

  13. The effects of variable sample biomass on comparative metagenomics.

    PubMed

    Chafee, Meghan; Maignien, Loïs; Simmons, Sheri L

    2015-07-01

    Longitudinal studies that integrate samples with variable biomass are essential to understand microbial community dynamics across space or time. Shotgun metagenomics is widely used to investigate these communities at the functional level, but little is known about the effects of combining low and high biomass samples on downstream analysis. We investigated the interacting effects of DNA input and library amplification by polymerase chain reaction on comparative metagenomic analysis using dilutions of a single complex template from an Arabidopsis thaliana-associated microbial community. We modified the Illumina Nextera kit to generate high-quality large-insert (680 bp) paired-end libraries using a range of 50 pg to 50 ng of input DNA. Using assembly-based metagenomic analysis, we demonstrate that DNA input level has a significant impact on community structure due to overrepresentation of low-GC genomic regions following library amplification. In our system, these differences were largely superseded by variations between biological replicates, but our results advocate verifying the influence of library amplification on a case-by-case basis. Overall, this study provides recommendations for quality filtering and de-replication prior to analysis, as well as a practical framework to address the issue of low biomass or biomass heterogeneity in longitudinal metagenomic surveys.

  14. Generalized Confidence Intervals and Fiducial Intervals for Some Epidemiological Measures

    PubMed Central

    Bebu, Ionut; Luta, George; Mathew, Thomas; Agan, Brian K.

    2016-01-01

    For binary outcome data from epidemiological studies, this article investigates the interval estimation of several measures of interest in the absence or presence of categorical covariates. When covariates are present, the logistic regression model as well as the log-binomial model are investigated. The measures considered include the common odds ratio (OR) from several studies, the number needed to treat (NNT), and the prevalence ratio. For each parameter, confidence intervals are constructed using the concepts of generalized pivotal quantities and fiducial quantities. Numerical results show that the confidence intervals so obtained exhibit satisfactory performance in terms of maintaining the coverage probabilities even when the sample sizes are not large. An appealing feature of the proposed solutions is that they are not based on maximization of the likelihood, and hence are free from convergence issues associated with the numerical calculation of the maximum likelihood estimators, especially in the context of the log-binomial model. The results are illustrated with a number of examples. The overall conclusion is that the proposed methodologies based on generalized pivotal quantities and fiducial quantities provide an accurate and unified approach for the interval estimation of the various epidemiological measures in the context of binary outcome data with or without covariates. PMID:27322305

  15. The Effect of Tear Supplementation on Ocular Surface Sensations during the Interblink Interval in Patients with Dry Eye

    PubMed Central

    Dienes, Lóránt; Kiss, Huba J.; Perényi, Kristóf; Szepessy, Zsuzsanna; Nagy, Zoltán Z.; Barsi, Árpád; Acosta, M. Carmen; Gallar, Juana; Kovács, Illés

    2015-01-01

    Purpose To investigate the characteristics of ocular surface sensations and corneal sensitivity during the interblink interval before and after tear supplementation in dry eye patients. Methods Twenty subjects (41.88±14.37 years) with dry eye symptoms were included in the dry eye group. Fourteen subjects (39.13±11.27 years) without any clinical signs and/or symptoms of dry eye were included in the control group. Tear film dynamics was assessed by non-invasive tear film breakup time (NI-BUT) in parallel with continuous recordings of ocular sensations during forced blinking. Corneal sensitivity to selective stimulation of corneal mechano-, cold and chemical receptors was assessed using a gas esthesiometer. All the measurements were made before and 5 min after saline and hydroxypropyl-guar (HP-guar) drops. Results In dry eye patients the intensity of irritation increased rapidly after the last blink during forced blinking, while in controls there was no alteration in the intensity during the first 10 sec followed by an exponential increase. Irritation scores were significantly higher in dry eye patients throughout the entire interblink interval compared to controls (p<0.004). NI-BUT significantly increased after HP-guar (p = 0.003) but not after saline drops (p = 0.14). In both groups, either after saline or HP-guar the shape of symptom intensity curves remained the same with significantly lower irritation scores (p<0.004), however after HP-guar the decrease was significantly more pronounced (p<0.004). Corneal sensitivity to selective mechanical, cold and chemical stimulation decreased significantly in both groups after HP-guar (p<0.05), but not after saline drops (p>0.05). Conclusion Ocular surface irritation responses due to tear film drying are considerably increased in dry eye patients compared to normal subjects. Although tear supplementation improves the protective tear film layer, and thus reduce unpleasant sensory responses, the rapid rise in discomfort is

  16. The effects of sampling frequency on the climate statistics of the European Centre for Medium-Range Weather Forecasts

    NASA Astrophysics Data System (ADS)

    Phillips, Thomas J.; Gates, W. Lawrence; Arpe, Klaus

    1992-12-01

    The effects of sampling frequency on the first- and second-moment statistics of selected European Centre for Medium-Range Weather Forecasts (ECMWF) model variables are investigated in a simulation of "perpetual July" with a diurnal cycle included and with surface and atmospheric fields saved at hourly intervals. The shortest characteristic time scales (as determined by the e-folding time of lagged autocorrelation functions) are those of ground heat fluxes and temperatures, precipitation and runoff, convective processes, cloud properties, and atmospheric vertical motion, while the longest time scales are exhibited by soil temperature and moisture, surface pressure, and atmospheric specific humidity, temperature, and wind. The time scales of surface heat and momentum fluxes and of convective processes are substantially shorter over land than over oceans. An appropriate sampling frequency for each model variable is obtained by comparing the estimates of first- and second-moment statistics determined at intervals ranging from 2 to 24 hours with the "best" estimates obtained from hourly sampling. Relatively accurate estimation of first- and second-moment climate statistics (10% errors in means, 20% errors in variances) can be achieved by sampling a model variable at intervals that usually are longer than the bandwidth of its time series but that often are shorter than its characteristic time scale. For the surface variables, sampling at intervals that are nonintegral divisors of a 24-hour day yields relatively more accurate time-mean statistics because of a reduction in errors associated with aliasing of the diurnal cycle and higher-frequency harmonics. The superior estimates of first-moment statistics are accompanied by inferior estimates of the variance of the daily means due to the presence of systematic biases, but these probably can be avoided by defining a different measure of low-frequency variability. Estimates of the intradiurnal variance of accumulated

  17. Effects of microbial lipases on hydrolyzed milk fat at different time intervals in flavour development and oxidative stability.

    PubMed

    Omar, Khamis Ali; Gounga, Mahamadou Elhadji; Liu, Ruijie; Mlyuka, Erasto; Wang, Xingguo

    2016-02-01

    The interest in application of biocatalysis during natural milk fat flavours development has increased rapidly and lipases have become the most studied group in the development of bovine milk fat flavours. Lipozyme-435, Novozyme-435 and Thermomyces lanuginosus Immobilized (TL-IM) lipases were used to hydrolyze anhydrous milk fat (AMF) and anhydrous buffalo milk fat (ABF) and their volatile flavouring compounds were identified by solid-phase micro-extraction gas chromatography/mass spectrometry (SPME-GC/MS) and then compared at three hydrolysis intervals. Both AMF and ABF after lipolysis produced high amount of butanoic and hexanoic acids and other flavouring compounds; however, highest amount were produced by Lipozyme-435 and Novozyme-435 followed by TL-IM. The hydrolyzed products were assessed by Rancimat-743 for oxidative stability and found both that, for AMF and ABF treated butter oil, Lipozyme-435 and TL-IM were generally more stable compared to Novozyme-435. For both AMF and ABF treated butter oil, Lipozyme-435 was observed to cause no further oxidation consequences which indicates Lipozyme-435 was stable during hydrolysis at 55 °C for 24 h. PMID:27162383

  18. Effects of microbial lipases on hydrolyzed milk fat at different time intervals in flavour development and oxidative stability.

    PubMed

    Omar, Khamis Ali; Gounga, Mahamadou Elhadji; Liu, Ruijie; Mlyuka, Erasto; Wang, Xingguo

    2016-02-01

    The interest in application of biocatalysis during natural milk fat flavours development has increased rapidly and lipases have become the most studied group in the development of bovine milk fat flavours. Lipozyme-435, Novozyme-435 and Thermomyces lanuginosus Immobilized (TL-IM) lipases were used to hydrolyze anhydrous milk fat (AMF) and anhydrous buffalo milk fat (ABF) and their volatile flavouring compounds were identified by solid-phase micro-extraction gas chromatography/mass spectrometry (SPME-GC/MS) and then compared at three hydrolysis intervals. Both AMF and ABF after lipolysis produced high amount of butanoic and hexanoic acids and other flavouring compounds; however, highest amount were produced by Lipozyme-435 and Novozyme-435 followed by TL-IM. The hydrolyzed products were assessed by Rancimat-743 for oxidative stability and found both that, for AMF and ABF treated butter oil, Lipozyme-435 and TL-IM were generally more stable compared to Novozyme-435. For both AMF and ABF treated butter oil, Lipozyme-435 was observed to cause no further oxidation consequences which indicates Lipozyme-435 was stable during hydrolysis at 55 °C for 24 h.

  19. Effects of a Single Session of High Intensity Interval Treadmill Training on Corticomotor Excitability following Stroke: Implications for Therapy

    PubMed Central

    Stinear, James W.; Kanekar, Neeta

    2016-01-01

    Objective. High intensity interval treadmill training (HIITT) has been gaining popularity for gait rehabilitation after stroke. In this study, we examined the changes in excitability of the lower limb motor cortical representation (M1) in chronic stroke survivors following a single session of HIITT. We also determined whether exercise-induced changes in excitability could be modulated by transcranial direct current stimulation (tDCS) enhanced with a paretic ankle skill acquisition task. Methods. Eleven individuals with chronic stroke participated in two 40-minute treadmill-training sessions: HIITT alone and HITT preceded by anodal tDCS enhanced with a skill acquisition task (e-tDCS+HIITT). Transcranial magnetic stimulation (TMS) was used to assess corticomotor excitability of paretic and nonparetic tibialis anterior (TA) muscles. Results. HIIT alone reduced paretic TA M1 excitability in 7 of 11 participants by ≥ 10%. e-tDCS+HIITT increased paretic TA M1 excitability and decreased nonparetic TA M1 excitability. Conclusions. HIITT suppresses corticomotor excitability in some people with chronic stroke. When HIITT is preceded by tDCS in combination with a skill acquisition task, the asymmetry of between-hemisphere corticomotor excitability is reduced. Significance. This study provides preliminary data indicating that the cardiovascular benefits of HIITT may be achieved without suppressing motor excitability in some stroke survivors. PMID:27738524

  20. Effects of mild calorie restriction and high-intensity interval walking in middle-aged and older overweight Japanese.

    PubMed

    Sawashita, Jinko; Onitsuka, Sayaka; Gen-no, Hirokazu; Ishikawa, Shinobu; Iino, Fumie; Tateishi, Norihiko; Murakami, Takeo; Seki, Yoichi; Nagaiwa, Toshiyuki; Hanaoka, Masaaki; Hama, Sumio; Nose, Hiroshi; Higuchi, Keiichi

    2009-10-01

    We investigated whether a combination of mild calorie restriction (MCR) and high-intensity interval walking (HIW) improved physical fitness more than HIW alone in middle-aged and older overweight Japanese (40-69years old, BMI23.6kg/m(2)). Forty-seven women and 16 men were divided into MCR+HIW and HIW groups. All subjects performed HIW: 5 sets of 3-min low-intensity walking (40% peak aerobic capacity for walking, VO(2peak)) and 3-min high-intensity walking (70% VO(2peak)) per day, 4days per week, for 16weeks while energy expenditure was monitored with a tri-axial accelerometer. The MCR+HIW group consumed meal replacement formula (240kcal): a mixture of low-carbohydrates and -fat and high-protein, for either lunch or dinner everyday and therefore, had approximately 87% of the energy intake of the HIW group during the intervention period. Although the HIW group showed improvements in BMI, blood pressure, and several blood chemicals, the MCR+HIW group had greater improvement. Moreover, the medical expenditure for the 6months including the intervention period was 59% lower in the MCR+HIW group than in the HIW group. Our strategy of a short-term combination of MCR and HIW may thus prevent lifestyle-associated diseases and improve health in middle-aged and older overweight Japanese.

  1. On the Effects of Signaling Reinforcer Probability and Magnitude in Delayed Matching to Sample

    ERIC Educational Resources Information Center

    Brown, Glenn S.; White, K. Geoffrey

    2005-01-01

    Two experiments examined whether postsample signals of reinforcer probability or magnitude affected the accuracy of delayed matching to sample in pigeons. On each trial, red or green choice responses that matched red or green stimuli seen shortly before a variable retention interval were reinforced with wheat access. In Experiment 1, the…

  2. The Effect of a 12-Week Moderate Intensity Interval Training Program on the Antioxidant Defense Capability and Lipid Profile in Men Smoking Cigarettes or Hookah: A Cohort Study

    PubMed Central

    Koubaa, Abdessalem; Triki, Moez; Trabelsi, Hajer; Baati, Hamza; Sahnoun, Zouhair; Hakim, Ahmed

    2015-01-01

    Aim. To examine the impact of interval training program on the antioxidant defense capability and lipid profile in men smoking cigarettes or hookah unable or unwilling to quit smoking. Methods. Thirty-five participants performed an interval training (2 : 1 work : rest ratio) 3 times a week for 12 weeks at an intensity of 70% of VO2max. All subjects were subjected to a biochemical test session before and after the training program. Results. The increase of total antioxidant status (TAS), glutathione peroxidase (GPx), and α-tocopherol, is significant only for cigarette smokers (CS) and hookah smokers (HS) groups. The decrease of malondialdehyde (MDA) and the increase of glutathione reductase (GR) are more pronounced in smokers groups compared to those of nonsmokers (NS). Superoxide dismutase (SOD) increases in NS, CS, and HS groups by 10.1%, 19.5%, and 13.3%, respectively (P < 0.001). Likewise, a significant improvement of high-density lipoprotein cholesterol (HDL-C) and TC/HDL-C ratio was observed in CS and HS groups (P < 0.05). Conclusion. Although the interval training program does not have a significant effect on blood lipid levels, it seems to be very beneficial in the defense and prevention programs of oxidative stress. PMID:25664340

  3. Effect of inter-cycle interval on oocyte production in humans in the presence of the weak androgen DHEA and follicle stimulating hormone: a case-control study

    PubMed Central

    2014-01-01

    Background In various animal models androgens have been demonstrated to enhance follicle stimulating hormone (FSH) activity on granulosa cells during small growing follicle stages. To assess whether similar synergism may also exist in humans we investigated women on androgen (dehydroepiandrosterone, DHEA) supplementation with varying concomitant FSH exposure. Methods In a case controlled cohort study we determine if time interval between IVF cycles of IVF treatment with FSH had an effect on ovarian response to ovulation induction in women supplemented with DHEA. Among 85 women with known low functional ovarian reserve (LFOR), supplemented with DHEA, and undergoing at least 3 consecutive IVF cycles, 68 demonstrated short (<120 days) intervals between repeated cycles (Group 1) and were, therefore, considered to have consistent FSH exposure. In contrast 17 women (Group 2) demonstrated long (> = 120 days) intervals between repeated cycles and, therefore, were considered to demonstrate inconsistent FSH exposure. Trends in oocyte yields were compared between these groups, utilizing mixed model repeated measures ANOVA, adjusted for initial age and FSH dose. Results Only women in Group I demonstrated a linear increase in oocyte yields across their three cycles of treatments (F = 7.92; df 1, 68.6; p = 0.017). Moreover, the analysis revealed a significant interaction between the two patient groups and cycle number for retrieved oocytes (F = 6.32, df = 2, 85.9, p = 0.003). Conclusions This study offers preliminary confirmatory evidence that repeated short interval exposure to androgens in combination with FSH improves human FOR. A higher level of evidence will require prospectively randomized studies. PMID:25048047

  4. The effect of low- vs high-cadence interval training on the freely chosen cadence and performance in endurance-trained cyclists.

    PubMed

    Whitty, Anthony G; Murphy, Aron J; Coutts, Aaron J; Watsford, Mark L

    2016-06-01

    The aim of this study was to determine the effects of high- and low-cadence interval training on the freely chosen cadence (FCC) and performance in endurance-trained cyclists. Sixteen male endurance-trained cyclists completed a series of submaximal rides at 60% maximal power (Wmax) at cadences of 50, 70, 90, and 110 r·min(-1), and their FCC to determine their preferred cadence, gross efficiency (GE), rating of perceived exertion, and crank torque profile. Performance was measured via a 15-min time trial, which was preloaded with a cycle at 60% Wmax. Following the testing, the participants were randomly assigned to a high-cadence (HC) (20% above FCC) or a low-cadence (LC) (20% below FCC) group for 18 interval-based training sessions over 6 weeks. The HC group increased their FCC from 92 to 101 r·min(-1) after the intervention (p = 0.01), whereas the LC group remained unchanged (93 r·min(-1)). GE increased from 22.7% to 23.6% in the HC group at 90 r·min(-1) (p = 0.05), from 20.0% to 20.9% at 110 r·min(-1) (p = 0.05), and from 22.8% to 23.2% at their FCC. Both groups significantly increased their total distance and average power output following training, with the LC group recording a superior performance measure. There were minimal changes to the crank torque profile in both groups following training. This study demonstrated that the FCC can be altered with HC interval training and that the determinants of the optimal cycling cadence are multifactorial and not completely understood. Furthermore, LC interval training may significantly improve time-trial results of short duration as a result of an increase in strength development or possible neuromuscular adaptations. PMID:27175601

  5. Evaluation of the Effects of Light Intensity and Time Interval After the Start of Scotophase on the Female Flight Propensity of Asian Gypsy Moth (Lepidoptera: Erebidae).

    PubMed

    Chen, Fang; Shi, Juan; Keena, Melody

    2016-04-01

    Asian gypsy moth, Lymantria dispar L. (Lepidoptera: Erebidae), females are capable of flight, but little is known about what causes the variation in flight propensity that has been observed. The female flight propensity and capability of Asian gypsy moth from seven geographic populations (three from China, two from Russia, one from Japan, and one from Korea) were compared under all combinations of three light intensities (0.05, 0.10, and 0.40 lux) and during three time intervals after the start of scotophase. A total of 567 females were flight tested. Female flight propensity, time to initiate walking, fanning, and flying, and duration of fanning differed significantly among geographic populations. Females were less likely to voluntarily fly during the 0-1-h time interval after the start of scotophase than during the later time intervals (1-2 and 2-3 h), suggesting that the light intensity cue has to occur at the correct time after the expected start of scotophase for flight initiation. Light intensity did not significantly affect the proportion of females that voluntarily flew, but did impact the timing of the walking and fanning preflight behaviors. The interaction between light intensity and time interval after the start of scotophase had a significant effect on the proportion of females that fanned. The proportion of females with sustained flight capability varied among the populations evaluated. These results may aid in determining the risk of Asian gypsy moth dispersal, but further work is needed to assess other factors that play a role in flight propensity. PMID:26748672

  6. Evaluation of the Effects of Light Intensity and Time Interval After the Start of Scotophase on the Female Flight Propensity of Asian Gypsy Moth (Lepidoptera: Erebidae).

    PubMed

    Chen, Fang; Shi, Juan; Keena, Melody

    2016-04-01

    Asian gypsy moth, Lymantria dispar L. (Lepidoptera: Erebidae), females are capable of flight, but little is known about what causes the variation in flight propensity that has been observed. The female flight propensity and capability of Asian gypsy moth from seven geographic populations (three from China, two from Russia, one from Japan, and one from Korea) were compared under all combinations of three light intensities (0.05, 0.10, and 0.40 lux) and during three time intervals after the start of scotophase. A total of 567 females were flight tested. Female flight propensity, time to initiate walking, fanning, and flying, and duration of fanning differed significantly among geographic populations. Females were less likely to voluntarily fly during the 0-1-h time interval after the start of scotophase than during the later time intervals (1-2 and 2-3 h), suggesting that the light intensity cue has to occur at the correct time after the expected start of scotophase for flight initiation. Light intensity did not significantly affect the proportion of females that voluntarily flew, but did impact the timing of the walking and fanning preflight behaviors. The interaction between light intensity and time interval after the start of scotophase had a significant effect on the proportion of females that fanned. The proportion of females with sustained flight capability varied among the populations evaluated. These results may aid in determining the risk of Asian gypsy moth dispersal, but further work is needed to assess other factors that play a role in flight propensity.

  7. Sampling variability in estimates of flow characteristics in coarse-bed channels: Effects of sample size

    NASA Astrophysics Data System (ADS)

    Cienciala, Piotr; Hassan, Marwan A.

    2016-03-01

    Adequate description of hydraulic variables based on a sample of field measurements is challenging in coarse-bed streams, a consequence of high spatial heterogeneity in flow properties that arises due to the complexity of channel boundary. By applying a resampling procedure based on bootstrapping to an extensive field data set, we have estimated sampling variability and its relationship with sample size in relation to two common methods of representing flow characteristics, spatially averaged velocity profiles and fitted probability distributions. The coefficient of variation in bed shear stress and roughness length estimated from spatially averaged velocity profiles and in shape and scale parameters of gamma distribution fitted to local values of bed shear stress, velocity, and depth was high, reaching 15-20% of the parameter value even at the sample size of 100 (sampling density 1 m-2). We illustrated implications of these findings with two examples. First, sensitivity analysis of a 2-D hydrodynamic model to changes in roughness length parameter showed that the sampling variability range observed in our resampling procedure resulted in substantially different frequency distributions and spatial patterns of modeled hydraulic variables. Second, using a bedload formula, we showed that propagation of uncertainty in the parameters of a gamma distribution used to model bed shear stress led to the coefficient of variation in predicted transport rates exceeding 50%. Overall, our findings underscore the importance of reporting the precision of estimated hydraulic parameters. When such estimates serve as input into models, uncertainty propagation should be explicitly accounted for by running ensemble simulations.

  8. Prediction and modeling of effects on the QTc interval for clinical safety margin assessment, based on single-ascending-dose study data with AZD3839.

    PubMed

    Sparve, Erik; Quartino, Angelica L; Lüttgen, Maria; Tunblad, Karin; Gårdlund, Anna Teiling; Fälting, Johanna; Alexander, Robert; Kågström, Jens; Sjödin, Linnea; Bulgak, Alexander; Al-Saffar, Ahmad; Bridgland-Taylor, Matthew; Pollard, Chris; Swedberg, Michael D B; Vik, Torbjörn; Paulsson, Björn

    2014-08-01

    Corrected QT interval (QTc) prolongation in humans is usually predictable based on results from preclinical findings. This study confirms the signal from preclinical cardiac repolarization models (human ether-a-go-go-related gene, guinea pig monophasic action potential, and dog telemetry) on the clinical effects on the QTc interval. A thorough QT/QTc study is generally required for bioavailable pharmaceutical compounds to determine whether or not a drug shows a QTc effect above a threshold of regulatory interest. However, as demonstrated in this AZD3839 [(S)-1-(2-(difluoromethyl)pyridin-4-yl)-4-fluoro-1-(3-(pyrimidin-5-yl)phenyl)-1H-isoindol-3-amine hemifumarate] single-ascending-dose (SAD) study, high-resolution digital electrocardiogram data, in combination with adequate efficacy biomarker and pharmacokinetic data and nonlinear mixed effects modeling, can provide the basis to safely explore the margins to allow for robust modeling of clinical effect versus the electrophysiological risk marker. We also conclude that a carefully conducted SAD study may provide reliable data for effective early strategic decision making ahead of the thorough QT/QTc study.

  9. The effect of burst duration, interstimulus onset interval, and loudspeaker arrangement on auditory apparent motion in the free field.

    PubMed

    Strybel, T Z; Neale, W

    1994-12-01

    The illusion of auditory apparent motion (AAM) was examined in order to determine the burst durations and interstimulus onset intervals (ISOIs) at which AAM is heard when spatial information regarding source location was varied. In the first experiment AAM was examined in the free field under monaural and binaural listening conditions. AAM was heard at the same burst duration-ISOI combinations for both listening conditions, but the location of the lead source could be determined only under binaural listening. In the second experiment AAM was measured with two and three sound sources. The number of sources did not affect the burst duration-ISOI combinations that produced AAM, but did affect the determination of the location of the lead source. In the third experiment AAM was tested when the sources were located in the median plane. The sources were located either at 0 degrees and 180 degrees azimuth, or both at 0 degrees azimuth, one in the horizontal plane and one 20 degrees above. The location of the speakers did not affect the timing requirements for the perception of AAM, only the timing requirements for the detection of the lead source. In the fourth experiment, AAM was measured when the vertical separation between the sources was either 2.5 degrees or 20 degrees. AAM was heard at both separations, even though 2.5 degrees is less than the vertical MAA. In each of these experiments only burst duration and ISOI determined whether motion was heard. Localization cues were important only for the determination of the direction of motion.

  10. Effect on Survival of Longer Intervals Between Confirmed Diagnosis and Treatment Initiation Among Low-Income Women With Breast Cancer

    PubMed Central

    McLaughlin, John M.; Anderson, Roger T.; Ferketich, Amy K.; Seiber, Eric E.; Balkrishnan, Rajesh; Paskett, Electra D.

    2012-01-01

    Purpose To determine the impact of longer periods between biopsy-confirmed breast cancer diagnosis and the initiation of treatment (Dx2Tx) on survival. Patients and Methods This study was a noninterventional, retrospective analysis of adult female North Carolina Medicaid enrollees diagnosed with breast cancer from January 1, 2000, through December, 31, 2002, in the linked North Carolina Central Cancer Registry–Medicaid Claims database. Follow-up data were available through July 31, 2006. Cox proportional hazards regression models were constructed to evaluate the impact on survival of delaying treatment ≥ 60 days after a confirmed diagnosis of breast cancer. Results The study cohort consisted of 1,786 low-income, adult women with a mean age of 61.6 years. A large proportion of the patients (44.3%) were racial minorities. Median time from biopsy-confirmed diagnosis to treatment initiation was 22 days. Adjusted Cox proportional hazards regression showed that although Dx2Tx length did not affect survival among those diagnosed at early stage, among late-stage patients, intervals between diagnosis and first treatment ≥ 60 days were associated with significantly worse overall survival (hazard ratio [HR], 1.66; 95% CI, 1.00 to 2.77; P = .05) and breast cancer–specific survival (HR, 1.85; 95% CI, 1.04 to 3.27; P = .04). Conclusion One in 10 women waited ≥ 60 days to initiate treatment after a diagnosis of breast cancer. Waiting ≥ 60 days to initiate treatment was associated with a significant 66% and 85% increased risk of overall and breast cancer–related death, respectively, among late-stage patients. Interventions designed to increase the timeliness of receiving breast cancer treatments should target late-stage patients, and clinicians should strive to promptly triage and initiate treatment for patients diagnosed at late stage. PMID:23169521

  11. Effect of addition of lycopene to calcium hydroxide and chlorhexidine as intracanal medicament on fracture resistance of radicular dentin at two different time intervals: An in vitro study

    PubMed Central

    Madhusudhana, Koppolu; Archanagupta, Kasamsetty; Suneelkumar, Chinni; Lavanya, Anumula; Deepthi, Mandava

    2015-01-01

    Background: Long-term use of intracanal medicaments such as calcium hydroxide (CH) reduces the fracture resistance of dentin. The present study was undertaken to evaluate the fracture resistance of radicular dentin on long-term use of CH, chlorhexidine (CHX) with lycopene (LP). Aim: To compare the fracture resistance of radicular dentin when intracanal medicaments such as CH, CHX with LP were used for 1-week and 1-month time interval. Settings and Design: Sixty single-rooted extracted human permanent premolars were collected, and complete instrumentation was done. Samples were divided into three groups based on intracanal medicament used. Materials and Methods: Group 1 - no medicament was placed (CON), group 2 - mixture of 1.5 g of CH and 1 ml of 2% CHX (CHCHX), group 3 - mixture of 1.5 g of CH, 1 ml of CHX and 1 ml of 5% LP solution (CHCHXLP). After storage period of each group for 1-week and 1-month, middle 8 mm root cylinder was sectioned and tested for fracture resistance. Statistical Analysis: Results were analyzed using paired t-test. Results: At 1-month time interval, there was a statistically significant difference in fracture resistance between CHCHX and CHCHXLP groups. Conclusion: Addition of LP has not decreased the fracture resistance of radicular dentin after 1-month. PMID:26069405

  12. The Effects of Finite Sampling Corrections on State Assessment Sample Requirements. NAEP Validity Studies (NVS).

    ERIC Educational Resources Information Center

    Chromy, James R.

    States participating in the National Assessment of Educational Progress State Assessment program (state NAEP) are required to sample at least 2,500 students from at least 100 schools per subject assessed. In this ideal situation, 25 students are assessed for a subject in each school selected for that subject. Two problems have arisen: some states…

  13. The Effects of Finite Sampling on State Assessment Sample Requirements. NAEP Validity Studies. Working Paper Series.

    ERIC Educational Resources Information Center

    Chromy, James R.

    This study addressed statistical techniques that might ameliorate some of the sampling problems currently facing states with small populations participating in State National Assessment of Educational Progress (NAEP) assessments. The study explored how the application of finite population correction factors to the between-school component of…

  14. Effectiveness of laser sources for contactless sampling of explosives

    NASA Astrophysics Data System (ADS)

    Akmalov, Artem E.; Chistyakov, Alexander A.; Kotkovskii, Gennadii E.

    2016-05-01

    A mass-spectrometric study of photo processes initiated by ultraviolet (UV) laser radiation in explosives adsorbed on metal and dielectric substrates has been performed. A calibrated quadrupole mass spectrometer was used to determine a value of activation energy of desorption and a quantity of explosives desorbed by laser radiation. A special vacuumoptical module was elaborated and integrated into a vacuum mass-spectrometric system to focus the laser beam on a sample. It has been shown that the action of nanosecond laser radiation set at q= 107 - 108 W/cm2, λ=266 nm on adsorbed layers of molecules of trinitrotoluene (TNT ) and pentaerytritoltetranitrate (PETN) leads not only to an effective desorption, but also to the non-equilibrium dissociation of molecules with the formation of nitrogen oxide NO. The cyclotrimethylenetrinitramine (RDX) dissociation products are observed only at high laser intensities (q> 109 W/cm2) thus indicating the thermal nature of dissociation, whereas desorption of RDX is observed even at q> 107 W/cm2 from all substrates. Desorption is not observed for cyclotetramethylenetetranitramine (HMX) under single pulse action: the dissociation products NO and NO2 are registered only, whereas irradiation at 10Hz is quite effective for HMX desorption. The results clearly demonstrate a high efficiency of nanosecond laser radiation with λ = 266 nm, q ~ 107 - 108 W/cm2, Epulse= 1mJ for desorption of molecules of explosives from various surfaces.

  15. PREDICTION INTERVALS FOR INTEGRALS OF GAUSSIAN RANDOM FIELDS

    PubMed Central

    De Oliveira, Victor; Kone, Bazoumana

    2014-01-01

    Methodology is proposed for the construction of prediction intervals for integrals of Gaussian random fields over bounded regions (called block averages in the geostatistical literature) based on observations at a finite set of sampling locations. Two bootstrap calibration algorithms are proposed, termed indirect and direct, aimed at improving upon plug-in prediction intervals in terms of coverage probability. A simulation study is carried out that illustrates the effectiveness of both procedures, and these procedures are applied to estimate block averages of chromium traces in a potentially contaminated region in Switzerland. PMID:25431507

  16. Updating representations of temporal intervals.

    PubMed

    Danckert, James; Anderson, Britt

    2015-12-01

    Effectively engaging with the world depends on accurate representations of the regularities that make up that world-what we call mental models. The success of any mental model depends on the ability to adapt to changes-to 'update' the model. In prior work, we have shown that damage to the right hemisphere of the brain impairs the ability to update mental models across a range of tasks. Given the disparate nature of the tasks we have employed in this prior work (i.e. statistical learning, language acquisition, position priming, perceptual ambiguity, strategic game play), we propose that a cognitive module important for updating mental representations should be generic, in the sense that it is invoked across multiple cognitive and perceptual domains. To date, the majority of our tasks have been visual in nature. Given the ubiquity and import of temporal information in sensory experience, we examined the ability to build and update mental models of time. We had healthy individuals complete a temporal prediction task in which intervals were initially drawn from one temporal range before an unannounced switch to a different range of intervals. Separate groups had the second range of intervals switch to one that contained either longer or shorter intervals than the first range. Both groups showed significant positive correlations between perceptual and prediction accuracy. While each group updated mental models of temporal intervals, those exposed to shorter intervals did so more efficiently. Our results support the notion of generic capacity to update regularities in the environment-in this instance based on temporal information. The task developed here is well suited to investigations in neurological patients and in neuroimaging settings.

  17. Updating representations of temporal intervals.

    PubMed

    Danckert, James; Anderson, Britt

    2015-12-01

    Effectively engaging with the world depends on accurate representations of the regularities that make up that world-what we call mental models. The success of any mental model depends on the ability to adapt to changes-to 'update' the model. In prior work, we have shown that damage to the right hemisphere of the brain impairs the ability to update mental models across a range of tasks. Given the disparate nature of the tasks we have employed in this prior work (i.e. statistical learning, language acquisition, position priming, perceptual ambiguity, strategic game play), we propose that a cognitive module important for updating mental representations should be generic, in the sense that it is invoked across multiple cognitive and perceptual domains. To date, the majority of our tasks have been visual in nature. Given the ubiquity and import of temporal information in sensory experience, we examined the ability to build and update mental models of time. We had healthy individuals complete a temporal prediction task in which intervals were initially drawn from one temporal range before an unannounced switch to a different range of intervals. Separate groups had the second range of intervals switch to one that contained either longer or shorter intervals than the first range. Both groups showed significant positive correlations between perceptual and prediction accuracy. While each group updated mental models of temporal intervals, those exposed to shorter intervals did so more efficiently. Our results support the notion of generic capacity to update regularities in the environment-in this instance based on temporal information. The task developed here is well suited to investigations in neurological patients and in neuroimaging settings. PMID:26303026

  18. Arrow-Elicited Cueing Effects at Short Intervals: Rapid Attentional Orienting or Cue-Target Stimulus Conflict?

    ERIC Educational Resources Information Center

    Green, Jessica J.; Woldorff, Marty G.

    2012-01-01

    The observation of cueing effects (faster responses for cued than uncued targets) rapidly following centrally-presented arrows has led to the suggestion that arrows trigger rapid automatic shifts of spatial attention. However, these effects have primarily been observed during easy target-detection tasks when both cue and target remain on the…

  19. Guide for Calculating and Interpreting Effect Sizes and Confidence Intervals in Intellectual and Developmental Disability Research Studies

    ERIC Educational Resources Information Center

    Dunst, Carl J.; Hamby, Deborah W.

    2012-01-01

    This paper includes a nontechnical description of methods for calculating effect sizes in intellectual and developmental disability studies. Different hypothetical studies are used to illustrate how null hypothesis significance testing (NHST) and effect size findings can result in quite different outcomes and therefore conflicting results. Whereas…

  20. Depressive Realism and Outcome Density Bias in Contingency Judgments: The Effect of the Context and Intertrial Interval

    ERIC Educational Resources Information Center

    Msetfi, Rachel M.; Murphy, Robin A.; Simpson, Jane; Kornbrot, Diana E.

    2005-01-01

    The perception of the effectiveness of instrumental actions is influenced by depressed mood. Depressive realism (DR) is the claim that depressed people are particularly accurate in evaluating instrumentality. In two experiments, the authors tested the DR hypothesis using an action-outcome contingency judgment task. DR effects were a function of…

  1. The Effect of High-Intensity Interval Cycling Sprints Subsequent to Arm-Curl Exercise on Upper-Body Muscle Strength and Hypertrophy.

    PubMed

    Kikuchi, Naoki; Yoshida, Shou; Okuyama, Mizuki; Nakazato, Koichi

    2016-08-01

    Kikuchi, N, Yoshida, S, Okuyama, M, and Nakazato, K. The effect of high-intensity interval cycling sprints subsequent to arm-curl exercise on upper-body muscle strength and hypertrophy. J Strength Cond Res 30(8): 2318-2323, 2016-The purpose of this study was to examine whether lower limb sprint interval training (SIT) after arm resistance training (RT) influences training response of arm muscle strength and hypertrophy. Twenty men participated in this study. We divided subjects into RT group (n = 6) and concurrent training group (CT, n = 6). The RT program was designed to induce muscular hypertrophy (3 sets × 10 repetitions [reps] at 80% 1 repetition maximum [1RM] of arm-curl exercise) and was performed in an 8-week training schedule performed 3 times per week on nonconsecutive days. Subjects assigned to the CT group performed identical protocols as strength training and modified SIT (4 sets of 30-s maximal effort, separated in 4 m 30-s rest intervals) on the same day. Pretest and posttest maximal oxygen consumption (V[Combining Dot Above]O2max), muscle cross-sectional area (CSA), and 1RM were measured. Significant increase in V[Combining Dot Above]O2max from pretest to posttest was observed in the CT group (p = 0.010, effect size [ES] = 1.84) but not in the RT group (p = 0.559, ES = 0.35). Significant increase in CSA from pretest to posttest was observed in the RT group (p = 0.030, ES = 1.49) but not in the CT group (p = 0.110, ES = 1.01). Significant increase in 1RM from pretest to posttest was observed in the RT group (p = 0.021, ES = 1.57) but not in the CT group (p = 0.065, ES = 1.19). In conclusion, our data indicate that concurrent lower limb SIT interferes with arm muscle hypertrophy and strength.

  2. Greater effects of high- compared with moderate-intensity interval training on cardio-metabolic variables, blood leptin concentration and ratings of perceived exertion in obese adolescent females.

    PubMed

    Racil, G; Coquart, J B; Elmontassar, W; Haddad, M; Goebel, R; Chaouachi, A; Amri, M; Chamari, K

    2016-06-01

    This study examined the effects of high- vs. moderate-intensity interval training on cardiovascular fitness, leptin levels and ratings of perceived exertion (RPE) in obese female adolescents. Forty-seven participants were randomly assigned to one of three groups receiving either a 1:1 ratio of 15 s of effort comprising moderate-intensity interval training (MIIT at 80% maximal aerobic speed: MAS) or high-intensity interval training (HIIT at 100% MAS), with matched 15 s recovery at 50% MAS, thrice weekly, or a no-training control group. The HIIT and MIIT groups showed improved (p < 0.05) body mass (BM), BMI Z-score, and percentage of body fat (%BF). Only the HIIT group showed decreased waist circumference (WC) (p = 0.017). The effect of exercise on maximal oxygen uptake (VO2max) was significant (p = 0.019, ES = 0.48 and p = 0.010, ES = 0.57, HIIT and MIIT, respectively). The decrease of rate-pressure product (RPP) (p < 0.05, ES = 0.53 and ES = 0.46, HIIT and MIIT, respectively) followed the positive changes in resting heart rate and blood pressures. Blood glucose, insulin level and the homeostasis model assessment index for insulin decreased (p < 0.05) in both training groups. Significant decreases occurred in blood leptin (p = 0.021, ES = 0.67 and p = 0.011, ES = 0.73) and in RPE (p = 0.001, ES = 0.76 and p = 0.017, ES = 0.57) in HIIT and MIIT, respectively. In the post-intervention period, blood leptin was strongly associated with %BF (p < 0.001) and VO2max (p < 0.01) in the HIIT and MIIT groups, respectively, while RPE was strongly associated with BM (p < 0.01) in the HIIT group. The results suggest that high-intensity interval training may produce more positive effects on health determinants in comparison with the same training mode at a moderate intensity. PMID:27274107

  3. Greater effects of high- compared with moderate-intensity interval training on cardio-metabolic variables, blood leptin concentration and ratings of perceived exertion in obese adolescent females

    PubMed Central

    Coquart, JB; Elmontassar, W; Haddad, M; Goebel, R; Chaouachi, A; Amri, M; Chamari, K

    2016-01-01

    This study examined the effects of high- vs. moderate-intensity interval training on cardiovascular fitness, leptin levels and ratings of perceived exertion (RPE) in obese female adolescents. Forty-seven participants were randomly assigned to one of three groups receiving either a 1:1 ratio of 15 s of effort comprising moderate-intensity interval training (MIIT at 80% maximal aerobic speed: MAS) or high-intensity interval training (HIIT at 100% MAS), with matched 15 s recovery at 50% MAS, thrice weekly, or a no-training control group. The HIIT and MIIT groups showed improved (p < 0.05) body mass (BM), BMI Z-score, and percentage of body fat (%BF). Only the HIIT group showed decreased waist circumference (WC) (p = 0.017). The effect of exercise on maximal oxygen uptake (VO2max) was significant (p = 0.019, ES = 0.48 and p = 0.010, ES = 0.57, HIIT and MIIT, respectively). The decrease of rate-pressure product (RPP) (p < 0.05, ES = 0.53 and ES = 0.46, HIIT and MIIT, respectively) followed the positive changes in resting heart rate and blood pressures. Blood glucose, insulin level and the homeostasis model assessment index for insulin decreased (p < 0.05) in both training groups. Significant decreases occurred in blood leptin (p = 0.021, ES = 0.67 and p = 0.011, ES = 0.73) and in RPE (p = 0.001, ES = 0.76 and p = 0.017, ES = 0.57) in HIIT and MIIT, respectively. In the post-intervention period, blood leptin was strongly associated with %BF (p < 0.001) and VO2max (p < 0.01) in the HIIT and MIIT groups, respectively, while RPE was strongly associated with BM (p < 0.01) in the HIIT group. The results suggest that high-intensity interval training may produce more positive effects on health determinants in comparison with the same training mode at a moderate intensity. PMID:27274107

  4. Memory of a choice direction in a T maze as measured by spontaneous alternation in mice: Effects of intertrial interval and reward.

    PubMed

    Jaffard, R; Dubois, M; Galey, D

    1981-03-01

    Spontaneous alternation in a T maze was studied as a one trial learning paradigm in mice of the BALB/c strain. In the first experiment the combined effects of time interval between the first and second trial (intertrial interval: ITI), food deprivation and feeding given during the first trial, were shown to affect performance. Thus, on the one hand, the percentage of spontaneous alternation decreased as ITI increased; on the other hand, food reward dramatically improved spontaneous alternation for the 24-h ITI, but had no significant effect for 30-sec and 1-h ITI. Since the effect of feeding might be due either to an increase of arousal, thus favoring input of informations associated with the first choice, or to an improvement in memory consolidation, a second experiment was aimed at testing the effect of food given after the first trial. It was shown that, as in the first experiment, post-trial feeding improved spontaneous alternation on the second trial given 24 hours later with a temporal gradient of effect less than 30 min. These results clearly showed that the reinforcement of run to one side (first trial) increased the tendency to go to the other side 24 hours later. It is concluded that reinforcement might have two distinct effects: (i) according to SR theory, reinforcement increases conditioned responses and (ii), as shown here, acts on memory processes by preventing memory traces from fading. The fact that this last effect was only observed for long ITI suggests that short-term or transient memory and long-term memory are two relatively independent processes.

  5. Calibration of the complex matrix effects on the sampling of polycyclic aromatic hydrocarbons in milk samples using solid phase microextraction.

    PubMed

    Lin, Wei; Wei, Songbo; Jiang, Ruifen; Zhu, Fang; Ouyang, Gangfeng

    2016-08-24

    Solid phase microextraction (SPME), a simple, fast and promising sampling technique, has been widely used for complex sample analysis. However, complex matrices could modify the absorption property of coatings as well as the uptake kinetics of analytes, eventually biasing the quantification results. In the current study, we demonstrated the feasibility of a developed calibration method for the analysis of polycyclic aromatic hydrocarbons (PAHs) in complex milk samples. Effects of the complex matrices on the SPME sampling process and the sampling conditions were investigated. Results showed that short exposure time (pre-equilibrium SPME, PE-SPME) could increase the lifetime of coatings, and the complex matrices in milk samples could significantly influence the sampling kinetics of SPME. In addition, the optimized sampling time, temperature and dilution factor for PAHs were 10 min, 85 °C and 20, respectively. The obtained LODs and LOQs of all the PAHs were 0.1-0.8 ng/mL and 1.4-4.7 ng/mL, respectively. Furthermore, the accuracy of the proposed PE-SPME method for milk sampling was validated by the recoveries of the studied compounds in two concentration levels, which ranged from 75% to 110% for all the compounds. Finally, the proposed method was applied to the screening of PAHs in milk samples.

  6. Calibration of the complex matrix effects on the sampling of polycyclic aromatic hydrocarbons in milk samples using solid phase microextraction.

    PubMed

    Lin, Wei; Wei, Songbo; Jiang, Ruifen; Zhu, Fang; Ouyang, Gangfeng

    2016-08-24

    Solid phase microextraction (SPME), a simple, fast and promising sampling technique, has been widely used for complex sample analysis. However, complex matrices could modify the absorption property of coatings as well as the uptake kinetics of analytes, eventually biasing the quantification results. In the current study, we demonstrated the feasibility of a developed calibration method for the analysis of polycyclic aromatic hydrocarbons (PAHs) in complex milk samples. Effects of the complex matrices on the SPME sampling process and the sampling conditions were investigated. Results showed that short exposure time (pre-equilibrium SPME, PE-SPME) could increase the lifetime of coatings, and the complex matrices in milk samples could significantly influence the sampling kinetics of SPME. In addition, the optimized sampling time, temperature and dilution factor for PAHs were 10 min, 85 °C and 20, respectively. The obtained LODs and LOQs of all the PAHs were 0.1-0.8 ng/mL and 1.4-4.7 ng/mL, respectively. Furthermore, the accuracy of the proposed PE-SPME method for milk sampling was validated by the recoveries of the studied compounds in two concentration levels, which ranged from 75% to 110% for all the compounds. Finally, the proposed method was applied to the screening of PAHs in milk samples. PMID:27497004

  7. Interval neural networks

    SciTech Connect

    Patil, R.B.

    1995-05-01

    Traditional neural networks like multi-layered perceptrons (MLP) use example patterns, i.e., pairs of real-valued observation vectors, ({rvec x},{rvec y}), to approximate function {cflx f}({rvec x}) = {rvec y}. To determine the parameters of the approximation, a special version of the gradient descent method called back-propagation is widely used. In many situations, observations of the input and output variables are not precise; instead, we usually have intervals of possible values. The imprecision could be due to the limited accuracy of the measuring instrument or could reflect genuine uncertainty in the observed variables. In such situation input and output data consist of mixed data types; intervals and precise numbers. Function approximation in interval domains is considered in this paper. We discuss a modification of the classical backpropagation learning algorithm to interval domains. Results are presented with simple examples demonstrating few properties of nonlinear interval mapping as noise resistance and finding set of solutions to the function approximation problem.

  8. Modeling the Orbital Sampling Effect of Extrasolar Moons

    NASA Astrophysics Data System (ADS)

    Heller, René; Hippke, Michael; Jackson, Brian

    2016-04-01

    The orbital sampling effect (OSE) appears in phase-folded transit light curves of extrasolar planets with moons. Analytical OSE models have hitherto neglected stellar limb darkening and non-zero transit impact parameters and assumed that the moon is on a circular, co-planar orbit around the planet. Here, we present an analytical OSE model for eccentric moon orbits, which we implement in a numerical simulator with stellar limb darkening that allows for arbitrary transit impact parameters. We also describe and publicly release a fully numerical OSE simulator (PyOSE) that can model arbitrary inclinations of the transiting moon orbit. Both our analytical solution for the OSE and PyOSE can be used to search for exomoons in long-term stellar light curves such as those by Kepler and the upcoming PLATO mission. Our updated OSE model offers an independent method for the verification of possible future exomoon claims via transit timing variations and transit duration variations. Photometrically quiet K and M dwarf stars are particularly promising targets for an exomoon discovery using the OSE.

  9. EFFECT OF TRANSPORTING SALTSTONE SAMPLES PRIOR TO SET

    SciTech Connect

    Reigel, M.

    2013-05-21

    The Saltstone Sampling and Analyses Plan provides a basis for the quantity (and configuration) of saltstone grout samples required for conducting a study directed towards correlation of the Performance Assessment (PA) related properties of field-emplaced samples and samples processed and cured in the laboratory. The testing described in the saltstone sampling and analyses plan will be addressed in phases. The initial testing (Phase I) includes collecting samples from the process room in the Saltstone Production Facility (SPF) and transporting them to Savannah River National Laboratory (SRNL) where they will cure under a temperature profile that mimics the temperature in the Saltstone Disposal Unit (SDU) and then be analyzed. SRNL has previously recommended that after the samples of fresh (uncured) saltstone are obtained from the SPF process room, they are allowed to set prior to transporting them to SRNL for curing. The concern was that if the samples are transported before they are set, the vibrations during transport may cause artificial delay of structure development which could result in preferential settling or segregation of the saltstone slurry. However, the results of this testing showed there was no clear distinction between the densities of the cylinder sections for any of the transportation scenarios tested (1 day, 1 hour, and 0 minutes set time prefer to transportation) . The bottom section of each cylinder was the densest for each transportation scenario, which indicates some settling in all the samples. Triplicate hydraulic conductivity measurements on samples from each set of time and transportation scenarios indicated that those samples transported immediately after pouring had the highest hydraulic conductivity. Conversely, samples that were allowed to sit for an hour before being transported had the lowest hydraulic conductivity. However, the hydraulic conductivities of all three samples fell within an acceptable range. Based on the cured property

  10. Sampling effects on the identification of roadkill hotspots: Implications for survey design.

    PubMed

    Santos, Sara M; Marques, J Tiago; Lourenço, André; Medinas, Denis; Barbosa, A Márcia; Beja, Pedro; Mira, António

    2015-10-01

    Although locating wildlife roadkill hotspots is essential to mitigate road impacts, the influence of study design on hotspot identification remains uncertain. We evaluated how sampling frequency affects the accuracy of hotspot identification, using a dataset of vertebrate roadkills (n = 4427) recorded over a year of daily surveys along 37 km of roads. "True" hotspots were identified using this baseline dataset, as the 500-m segments where the number of road-killed vertebrates exceeded the upper 95% confidence limit of the mean, assuming a Poisson distribution of road-kills per segment. "Estimated" hotspots were identified likewise, using datasets representing progressively lower sampling frequencies, which were produced by extracting data from the baseline dataset at appropriate time intervals (1-30 days). Overall, 24.3% of segments were "true" hotspots, concentrating 40.4% of roadkills. For different groups, "true" hotspots accounted from 6.8% (bats) to 29.7% (small birds) of road segments, concentrating from <40% (frogs and toads, snakes) to >60% (lizards, lagomorphs, carnivores) of roadkills. Spatial congruence between "true" and "estimated" hotspots declined rapidly with increasing time interval between surveys, due primarily to increasing false negatives (i.e., missing "true" hotspots). There were also false positives (i.e., wrong "estimated" hotspots), particularly at low sampling frequencies. Spatial accuracy decay with increasing time interval between surveys was higher for smaller-bodied (amphibians, reptiles, small birds, small mammals) than for larger-bodied species (birds of prey, hedgehogs, lagomorphs, carnivores). Results suggest that widely used surveys at weekly or longer intervals may produce poor estimates of roadkill hotspots, particularly for small-bodied species. Surveying daily or at two-day intervals may be required to achieve high accuracy in hotspot identification for multiple species. PMID:26232568

  11. Sampling effects on the identification of roadkill hotspots: Implications for survey design.

    PubMed

    Santos, Sara M; Marques, J Tiago; Lourenço, André; Medinas, Denis; Barbosa, A Márcia; Beja, Pedro; Mira, António

    2015-10-01

    Although locating wildlife roadkill hotspots is essential to mitigate road impacts, the influence of study design on hotspot identification remains uncertain. We evaluated how sampling frequency affects the accuracy of hotspot identification, using a dataset of vertebrate roadkills (n = 4427) recorded over a year of daily surveys along 37 km of roads. "True" hotspots were identified using this baseline dataset, as the 500-m segments where the number of road-killed vertebrates exceeded the upper 95% confidence limit of the mean, assuming a Poisson distribution of road-kills per segment. "Estimated" hotspots were identified likewise, using datasets representing progressively lower sampling frequencies, which were produced by extracting data from the baseline dataset at appropriate time intervals (1-30 days). Overall, 24.3% of segments were "true" hotspots, concentrating 40.4% of roadkills. For different groups, "true" hotspots accounted from 6.8% (bats) to 29.7% (small birds) of road segments, concentrating from <40% (frogs and toads, snakes) to >60% (lizards, lagomorphs, carnivores) of roadkills. Spatial congruence between "true" and "estimated" hotspots declined rapidly with increasing time interval between surveys, due primarily to increasing false negatives (i.e., missing "true" hotspots). There were also false positives (i.e., wrong "estimated" hotspots), particularly at low sampling frequencies. Spatial accuracy decay with increasing time interval between surveys was higher for smaller-bodied (amphibians, reptiles, small birds, small mammals) than for larger-bodied species (birds of prey, hedgehogs, lagomorphs, carnivores). Results suggest that widely used surveys at weekly or longer intervals may produce poor estimates of roadkill hotspots, particularly for small-bodied species. Surveying daily or at two-day intervals may be required to achieve high accuracy in hotspot identification for multiple species.

  12. Effects of Data Sampling on Graphical Depictions of Learning

    ERIC Educational Resources Information Center

    Carey, Mary-Katherine; Bourret, Jason C.

    2014-01-01

    Continuous and discontinuous data-collection methods were compared in the context of discrete-trial programming. Archival data sets were analyzed using trial sampling (1st 5 trials, 1st 3 trials, and 1st trial only) and session sampling (every other session, every 3rd session, and every 5th session). Results showed that trial sampling…

  13. Effect of Paramecium biaurelia cytoplasm transplantation on the duration of the interautogamous interval (IAI) in Paramecium tetraurelia.

    PubMed

    Prajer, M

    1994-01-01

    The cytoplasm of Paramecium biaurelia in various stages of IAI was transplanted to Paramecium tetraurelia cells of the same clonal age. Such donor cytoplasm was effective in retardation of the expression of autogamy in the recipient clones. The results suggest that the cytoplasm of Paramecium biaurelia may contain the autogamous immaturity factor whose level changes during the run of IAI and whose specificity is the same as in Paramecium tetraurelia. PMID:7982503

  14. Protective effects of quercetin on cadmium fluoride induced oxidative stress at different intervals of time in mouse liver.

    PubMed

    Zargar, Seema; Siddiqi, Nikhat Jamal; Al Daihan, Sooad Khalaf; Wani, Tanveer A

    2015-01-01

    Quercetin, a member of the flavonoid family is a major antioxidant acquired in humans by food consumption, while Cadmium fluoride (CdF2) is one of the naturally occurring chemicals having adverse effects. The protective effect of quercetin on time dependent oxidative damage induced in mice liver by CdF2 was studied in the following groups of mice consisting of six mice each: (i) control group; (ii) mice treated with single i.p injection of 2 mg/kg bw CdF2 for 24 h; (iii) mice treated with single i.p injection of 2 mg/kg bw CdF2 for 48 h; (iv) mice treated with single i.p injection of quercetin (100 mg/kg bw); (v) mice treated with i.p injection of 100 mg/kg bw of quercetin followed by i.p injection of CdF2 (2 mg/kg bw) for 24 h; and (vi) mice treated with i.p injection of 100mg/kg bw of quercetin followed by CdF2 (2 mg/kg bw) for 48 h. Administration of quercetin two hours before CdF2 significantly reduced the biochemical alterations in reduced glutathione, ascorbic acid, lipid peroxidation, super oxide dismutase, catalase and total protein (p<0.05). Histopathology also showed the protective effect of quercetin. The livers treated with CdF2 were atrophic, markedly nodular, inflamed and necrotic. However, this effect was reduced to a minimum in the mice pre-treated for two hours with quercetin. PMID:25856559

  15. Seismicity and Deformation of Krafla Volcano, Iceland. Intervals of Low Seismicity Rate during Rapid Inflation Explained By the Kaiser Effect.

    NASA Astrophysics Data System (ADS)

    Heimisson, E. R.; Einarsson, P.; Sigmundsson, F.; Brandsdottir, B.

    2014-12-01

    The Krafla central volcano in NE-Iceland produced about 20 dike intrusions during a rifting episode 1975-1984. These intrusions were always preceded by inflation of the caldera. Once a dike started propagating rapid deflation was observed. The first deflation event began in December 1975 with a dike traveling laterally from the magma chamber. Leveling measurements revealed subsidence of 2 m close to the deflation center. In February 1976 a stage of inflation began and at the same time the seismicity rate in the caldera rose in good correlation with the inflation. A small intrusion started propagating in late September 1976 which was accompanied by maximum subsidence of about 14 cm. However in the next 3 inflation and deflation cycles the inflation periods were almost aseismic until the inflation level of previous cycle was exceeded. At that point a sharp increase in the caldera earthquake count was observed. This phenomenon was observed until late April 1977 when a fissure eruption occurred inside the caldera. By inverting leveling data from 87 stations for a Mogi source and regarding the volume change of the source as a measure of stress we suggest that this phenomenon can be explained by the Kaiser effect. The Kaiser effect is well known from rock mechanics where under cyclic loading and unloading rocks, and other materials, induce dramatic increase in acoustic emissions when the load exceeds that of previous cycles. Krafla demonstrated the same effect while the external stress field was not significantly changed during the aforementioned 3 inflation/deflation cycles. This condition was disturbed when eruption occurred inside the caldera. The state of stress in the vicinity of the magma chamber was changed and subsequent inflation periods were not accompanied by significant seismicity. These results indicate that the Kaiser effect is an important part of understanding the relationship between deformation and seismicity in active volcanoes. The importance of

  16. Effects of four weeks of high-intensity interval training and creatine supplementation on critical power and anaerobic working capacity in college-aged men.

    PubMed

    Kendall, Kristina L; Smith, Abbie E; Graef, Jennifer L; Fukuda, David H; Moon, Jordan R; Beck, Travis W; Cramer, Joel T; Stout, Jeffrey R

    2009-09-01

    The critical power test provides 2 measures, critical power (CP) and anaerobic working capacity (AWC). In theory, the CP measurement represents the maximal power output that can be maintained without fatigue, and AWC is an estimate of work capacity associated with muscle energy reserves. High-intensity interval training (HIIT) has been shown to be an effective training method for improving endurance performance, including VO2PEAK. In addition, creatine (Cr) supplementation has been reported to improve AWC without training; however, it has shown no effect on CP. The purpose of this study was to examine the effects of 4 weeks of HIIT with Cr supplementation on CP and AWC. Forty-two recreationally active men volunteered to participate in this study. Participants were randomly assigned to 1 of 3 groups: Cr (n = 16), 10 g Cr + 10 g dextrose; placebo (PL, n = 16), 20 g dextrose; control (CON, n = 10), no treatment. Before and after supplementation, each participant performed a maximal oxygen consumption test VO2PEAK on a cycle ergometer to establish peak power output (PPO). Participants then completed a CP test involving 3 exercise bouts with the workloads set as a percentage of their PPO to determine CP and AWC. After a 2-week familiarization period of training and supplementing, PPO, CP, and AWC were remeasured before an additional 4 weeks of HIIT and supplementation were completed. Training consisted of 5 sets of 2-minute exercise bouts with 1 minute rest in between performed on the cycle ergometer, with intensities based on PPO. A significant improvement in CP was observed in the Cr group (6.72% +/- 2.54%), whereas PL showed no significant change (3.87% +/- 2.30%), and CON significantly decreased (6.27% +/- 2.38%). Furthermore, no changes in AWC were observed in any of the groups after treatment. The current findings suggest that Cr supplementation may enhance the effects of intense interval endurance training on endurance performance changes.

  17. The effects of the preferential 5-HT2A agonist psilocybin on prepulse inhibition of startle in healthy human volunteers depend on interstimulus interval.

    PubMed

    Vollenweider, Franz X; Csomor, Philipp A; Knappe, Bernhard; Geyer, Mark A; Quednow, Boris B

    2007-09-01

    Schizophrenia patients exhibit impairments in prepulse inhibition (PPI) of the startle response. Hallucinogenic 5-HT(2A) receptor agonists are used for animal models of schizophrenia because they mimic some symptoms of schizophrenia in humans and induce PPI deficits in animals. Nevertheless, one report indicates that the 5-HT(2A) receptor agonist psilocybin increases PPI in healthy humans. Hence, we investigated these inconsistent results by assessing the dose-dependent effects of psilocybin on PPI in healthy humans. Sixteen subjects each received placebo or 115, 215, and 315 microg/kg of psilocybin at 4-week intervals in a randomized and counterbalanced order. PPI at 30-, 60-, 120-, 240-, and 2000-ms interstimulus intervals (ISIs) was measured 90 and 165 min after drug intake, coinciding with the peak and post-peak effects of psilocybin. The effects of psilocybin on psychopathological core dimensions and sustained attention were assessed by the Altered States of Consciousness Rating Scale (5D-ASC) and the Frankfurt Attention Inventory (FAIR). Psilocybin dose-dependently reduced PPI at short (30 ms), had no effect at medium (60 ms), and increased PPI at long (120-2000 ms) ISIs, without affecting startle reactivity or habituation. Psilocybin dose-dependently impaired sustained attention and increased all 5D-ASC scores with exception of Auditory Alterations. Moreover, psilocybin-induced impairments in sustained attention performance were positively correlated with reduced PPI at the 30 ms ISI and not with the concomitant increases in PPI observed at long ISIs. These results confirm the psilocybin-induced increase in PPI at long ISIs and reveal that psilocybin also produces a decrease in PPI at short ISIs that is correlated with impaired attention and consistent with deficient PPI in schizophrenia.

  18. System effects in sample self-stacking CZE: single analyte peak splitting of salt-containing samples.

    PubMed

    Malá, Zdena; Gebauer, Petr; Bocek, Petr

    2009-03-01

    In CZE one often gets more peaks than the number of sample components. In practice the additional peaks are often left unexplained or assigned to unidentified impurities or system peaks although cases exist when one analyte forms two or more regular distinct zones. One source of such effects are samples with high salt content that are generally assumed to bring higher sensitivity due to the sample self-stacking mechanism. The subject of this contribution is the theoretical and experimental investigation of the electromigration behavior of salt-containing samples. It is shown that they can exhibit splitting of the analyte zone into mutually independent parts detectable as well-developed distinct peaks. Theory based on velocity diagrams and computer simulations reveals that these effects originate in the transient phase of separation where electromigration dispersion profiles and sharp boundaries are formed and evolve. During this, the sample may induce parallel existence of several transient sharp boundaries (including system boundaries) that are simultaneously capable of stacking an analyte. Their electromigration is convergent and depending on whether they merge before the analyte destacks from them, permanent or transient double or multiple peaks are formed. Presented examples of anionic and cationic systems show good agreement with theory. The appearance of multiple peaks can be very variable, ranging from double or triple peaks to a major peak with a minor peak quite apart. Knowledge of the peak-splitting mechanism allows both to identify its presence in a given BGE and sample and to find effective remedy. PMID:19197903

  19. Effects on pseudopregnancy, pregnancy and interoestrous intervals of pharmacological suppression of prolactin secretion in female dogs and cats.

    PubMed

    Jöchle, W; Arbeiter, K; Post, K; Ballabio, R; D'Ver, A S

    1989-01-01

    Cabergoline, a new ergoline derivative, is a potent prolactin inhibitor. In this review, results are combined from previously published and unpublished blind laboratory and open clinical studies with cabergoline in pseudopregnant, pregnant and lactating bitches, in bitches with normal and prolonged cycles, and in pregnant queens. Dose-response studies in nursing bitches, using puppy weight as an endpoint, revealed that a dose of 5 micrograms/kg/day orally (for 5 days) was the optimal dose with a minimum of side effects. This dose effectively lowered blood prolactin concentrations in pregnant bitches and was partly luteolytic during the 1st half of gestation, and fully luteolytic during the 2nd half of gestation. Consequently, pregnancies were terminated in the 2nd half of pregnancy in the bitch, and in the queen. Treatment successes with pseudopregnancy and true and false lactation, including cases of eclampsia, were greater than 90%. The same level of success was seen in bitches with prolonged cycles (anoestrus). A 7-10-day treatment period resulted almost uniformly in oestrus, and restored fertility in greater than 80% of all bitches mated. Cycles were occasionally shortened in bitches treated for false lactation. Attempts to shorten cycles routinely in beagle bitches, in a commercial breeding operation, with a dose of 5 micrograms/kg/day for 14 days during months 4, 5 or 6 of the cycle were unsuccessful.

  20. Proximity effect thermometer for local temperature measurements on mesoscopic samples.

    SciTech Connect

    Aumentado, J.; Eom, J.; Chandrasekhar, V.; Baldo, P. M.; Rehn, L. E.; Materials Science Division; Northwestern Univ; Univ. of Chicago

    1999-11-29

    Using the strong temperature-dependent resistance of a normal metal wire in proximity to a superconductor, we have been able to measure the local temperature of electrons heated by flowing a direct-current (dc) in a metallic wire to within a few tens of millikelvin at low temperatures. By placing two such thermometers at different parts of a sample, we have been able to measure the temperature difference induced by a dc flowing in the samples. This technique may provide a flexible means of making quantitative thermal and thermoelectric measurements on mesoscopic metallic samples.

  1. Stimulus properties of fixed-interval responses.

    PubMed

    Buchman, I B; Zeiler, M D

    1975-11-01

    Responses in the first component of a chained schedule produced a change to the terminal component according to a fixed-interval schedule. The number of responses emitted in the fixed interval determined whether a variable-interval schedule of food presentation or extinction prevailed in the terminal component. In one condition, the variable-interval schedule was in effect only if the number of responses during the fixed interval was less than that specified; in another condition, the number of responses had to exceed that specified. The number of responses emitted in the fixed interval did not shift markedly in the direction required for food presentation. Instead, responding often tended to change in the opposite direction. Such an effect indicated that differential food presentation did not modify the reference behavior in accord with the requirement, but it was consistent with other data on fixed-interval schedule performance. Behavior in the terminal component, however, did reveal sensitivity to the relation between total responses emitted in the fixed interval and the availability of food. Response rate in the terminal component was a function of the proximity of the response number emitted in the fixed interval to that required for food presentation. Thus, response number served as a discriminative stimulus controlling subsequent performance.

  2. Antidot effects on micromagnetic behavior of Py ferromagnetic samples

    NASA Astrophysics Data System (ADS)

    Yetis, Hakan; Denizli, Haluk

    2016-09-01

    The coercivity and magnetic hysteresis behavior of permalloy (Py) samples have been studied in the presence of square arrays of the circular antidots. The open source OOMMF micromagnetic software is used to numerically solve the Landau-Lifshitz-Gilbert (LLG) equation. In calculations, Py samples are designed in such a way that they include a different number of antidot in an array which possess the same total surface area. In this way, the total Py region stayed unchanged despite the growing number of antidots in a fixed sample size. We found significant increase in the coercive field for the sample with the smallest antidot spacing. The results are discussed within the framework of superdomain (SD) and superdomain wall (SDW) formation.

  3. From clinical sites to biorepositories: effectiveness in blood sample management.

    PubMed

    Lefebvre, Céline; Tremblay, Nancy; Iverson, Bonnie; Wong, David; McWeeny, Kerri; Saghbini, Michael; Martinez, Heather; Hogan, Michael; Gaudet, Daniel; Arsenault, Steve

    2010-12-01

    Today's biobanks must work to take full advantage of collected samples, while maximizing sample quality and minimizing costs to sustain operations for a long period of time. This is a tall order that will require collaboration and compromise for both end-users and collection sites. This article discusses the efforts of the Génome Québec-Centre Hospitalier Affilié Universitaire Régional de Chicoutimi Biobank to fractionate blood samples for the simultaneous preservation of plasma and DNA-containing layers while minimizing resources required for shipping and transport. This article also describes methods for successful reproducible application of the plasma-depleted blood sample to GenPlates (GenVault, Carlsbad, CA).

  4. Detecting spatial structures in throughfall data: the effect of extent, sample size, sampling design, and variogram estimation method

    NASA Astrophysics Data System (ADS)

    Voss, Sebastian; Zimmermann, Beate; Zimmermann, Alexander

    2016-04-01

    In the last three decades, an increasing number of studies analyzed spatial patterns in throughfall to investigate the consequences of rainfall redistribution for biogeochemical and hydrological processes in forests. In the majority of cases, variograms were used to characterize the spatial properties of the throughfall data. The estimation of the variogram from sample data requires an appropriate sampling scheme: most importantly, a large sample and an appropriate layout of sampling locations that often has to serve both variogram estimation and geostatistical prediction. While some recommendations on these aspects exist, they focus on Gaussian data and high ratios of the variogram range to the extent of the study area. However, many hydrological data, and throughfall data in particular, do not follow a Gaussian distribution. In this study, we examined the effect of extent, sample size, sampling design, and calculation methods on variogram estimation of throughfall data. For our investigation, we first generated non-Gaussian random fields based on throughfall data with heavy outliers. Subsequently, we sampled the fields with three extents (plots with edge lengths of 25 m, 50 m, and 100 m), four common sampling designs (two grid-based layouts, transect and random sampling), and five sample sizes (50, 100, 150, 200, 400). We then estimated the variogram parameters by method-of-moments and residual maximum likelihood. Our key findings are threefold. First, the choice of the extent has a substantial influence on the estimation of the variogram. A comparatively small ratio of the extent to the correlation length is beneficial for variogram estimation. Second, a combination of a minimum sample size of 150, a design that ensures the sampling of small distances and variogram estimation by residual maximum likelihood offers a good compromise between accuracy and efficiency. Third, studies relying on method-of-moments based variogram estimation may have to employ at least

  5. Detecting spatial structures in throughfall data: The effect of extent, sample size, sampling design, and variogram estimation method

    NASA Astrophysics Data System (ADS)

    Voss, Sebastian; Zimmermann, Beate; Zimmermann, Alexander

    2016-09-01

    In the last decades, an increasing number of studies analyzed spatial patterns in throughfall by means of variograms. The estimation of the variogram from sample data requires an appropriate sampling scheme: most importantly, a large sample and a layout of sampling locations that often has to serve both variogram estimation and geostatistical prediction. While some recommendations on these aspects exist, they focus on Gaussian data and high ratios of the variogram range to the extent of the study area. However, many hydrological data, and throughfall data in particular, do not follow a Gaussian distribution. In this study, we examined the effect of extent, sample size, sampling design, and calculation method on variogram estimation of throughfall data. For our investigation, we first generated non-Gaussian random fields based on throughfall data with large outliers. Subsequently, we sampled the fields with three extents (plots with edge lengths of 25 m, 50 m, and 100 m), four common sampling designs (two grid-based layouts, transect and random sampling) and five sample sizes (50, 100, 150, 200, 400). We then estimated the variogram parameters by method-of-moments (non-robust and robust estimators) and residual maximum likelihood. Our key findings are threefold. First, the choice of the extent has a substantial influence on the estimation of the variogram. A comparatively small ratio of the extent to the correlation length is beneficial for variogram estimation. Second, a combination of a minimum sample size of 150, a design that ensures the sampling of small distances and variogram estimation by residual maximum likelihood offers a good compromise between accuracy and efficiency. Third, studies relying on method-of-moments based variogram estimation may have to employ at least 200 sampling points for reliable variogram estimates. These suggested sample sizes exceed the number recommended by studies dealing with Gaussian data by up to 100 %. Given that most previous

  6. Is Moderate Intensity Exercise Training Combined with High Intensity Interval Training More Effective at Improving Cardiorespiratory Fitness than Moderate Intensity Exercise Training Alone?

    PubMed Central

    Roxburgh, Brendon H.; Nolan, Paul B.; Weatherwax, Ryan M.; Dalleck, Lance C.

    2014-01-01

    The purpose of this study was to compare the effectiveness of either continuous moderate intensity exercise training (CMIET) alone vs. CMIET combined with a single weekly bout of high intensity interval training (HIIT) on cardiorespiratory fitness. Twenty nine sedentary participants (36.3 ± 6.9 yrs) at moderate risk of cardiovascular disease were recruited for 12 weeks of exercise training on a treadmill and cycle ergometer. Participants were randomised into three groups: CMIET + HIIT (n = 7; 8-12 x 60 sec at 100% VO2max, 150 sec active recovery), CMIET (n = 6; 30 min at 45-60% oxygen consumption reserve (VO2R)) and a sedentary control group (n = 7). Participants in the CMIET + HIIT group performed a single weekly bout of HIIT and four weekly sessions of CMIET, whilst the CMIET group performed five weekly CMIET sessions. Probabilistic magnitude-based inferences were determined to assess the likelihood that the true value of the effect represents substantial change. Relative VO2max increased by 10.1% (benefit possible relative to control) in in the CMIET + HIIT group (32.7 ± 9.2 to 36.0 ± 11.5 mL·kg-1·min-1) and 3.9% (benefit possible relative to control) in the CMIET group (33.2 ± 4.0 to 34.5 ± 6.1 mL·kg-1·min-1), whilst there was a 5.7% decrease in the control group (30.0 ± 4.6 to 28.3 ± 6.5 mL·kg-1·min-1). It was ‘unclear’ if a clinically significant difference existed between the effect of CMIET + HIIT and CMIET on the change in VO2max. Both exercising groups showed clinically meaningful improvements in VO2max. Nevertheless, it remains ‘unclear’ whether one type of exercise training regimen elicits a superior improvement in cardiorespiratory fitness relative to its counterpart. Key Points Both continuous moderate intensity exercise training (CMIET) alone and CMIET combined with a single weekly bout of high intensity interval training (CMIET + HIIT) elicit ‘possibly beneficial’ clinically meaningful improvements in cardiorespiratory

  7. The effects of sample scheduling and sample numbers on estimates of the annual fluxes of suspended sediment in fluvial systems

    USGS Publications Warehouse

    Horowitz, Arthur J.; Clarke, Robin T.; Merten, Gustavo Henrique

    2015-01-01

    Since the 1970s, there has been both continuing and growing interest in developing accurate estimates of the annual fluvial transport (fluxes and loads) of suspended sediment and sediment-associated chemical constituents. This study provides an evaluation of the effects of manual sample numbers (from 4 to 12 year−1) and sample scheduling (random-based, calendar-based and hydrology-based) on the precision, bias and accuracy of annual suspended sediment flux estimates. The evaluation is based on data from selected US Geological Survey daily suspended sediment stations in the USA and covers basins ranging in area from just over 900 km2 to nearly 2 million km2 and annual suspended sediment fluxes ranging from about 4 Kt year−1 to about 200 Mt year−1. The results appear to indicate that there is a scale effect for random-based and calendar-based sampling schemes, with larger sample numbers required as basin size decreases. All the sampling schemes evaluated display some level of positive (overestimates) or negative (underestimates) bias. The study further indicates that hydrology-based sampling schemes are likely to generate the most accurate annual suspended sediment flux estimates with the fewest number of samples, regardless of basin size. This type of scheme seems most appropriate when the determination of suspended sediment concentrations, sediment-associated chemical concentrations, annual suspended sediment and annual suspended sediment-associated chemical fluxes only represent a few of the parameters of interest in multidisciplinary, multiparameter monitoring programmes. The results are just as applicable to the calibration of autosamplers/suspended sediment surrogates currently used to measure/estimate suspended sediment concentrations and ultimately, annual suspended sediment fluxes, because manual samples are required to adjust the sample data/measurements generated by these techniques so that they provide depth-integrated and cross

  8. Effect of storage conditions on prothrombin time, activated partial thromboplastin time and fibrinogen concentration on canine plasma samples

    PubMed Central

    Casella, Stefania; Giannetto, Claudia; Giudice, Elisabetta

    2010-01-01

    The present study was to assess the effect of storage conditions on prothrombin time (PT), activated partial thromboplastin time (aPTT) and fibrinogen concentration in blood samples of healthy dogs. Thirty-five dogs of various breeds were included in the study. Citrated blood samples were obtained and plasma was divided into four aliquots to assess selected clotting parameters by means of a coagulometer. The first aliquot was analysed within 1 h after collection, while the remaining 3 were stored at 8℃ for 4, 8 and 24 h, respectively. One-way repeated measures analysis of variance documented a significant decreasing effect on PT at 24 h compared to 8 h and on fibrinogen concentration after 8 and 24 h compared to sampling time and at 4 and 24 h compared to 8 h post sampling. In conclusion, the results of this study indicate that only fibrinogen appears prone to significant decrease. In fact, aPTT is not substantially affected by refrigeration for at least 24 h post sampling and PT showed a statistical difference that does not necessary indicate biological significance as the results obtained were within reference intervals for the dog. PMID:20458152

  9. Effect of preservative solutions on preservation of Calliphora augur and Lucilia cuprina larvae (Diptera: Calliphoridae) with implications for post-mortem interval estimates.

    PubMed

    Day, Donnah M; Wallman, James F

    2008-07-18

    A major role of forensic entomology is to estimate the post-mortem interval. An entomologist's estimate of post-mortem interval is based on a series of generally valid assumptions, error in any of which can alter the accuracy of an estimate. The initial process of collecting and preserving maggots can itself lead to error, as can the method of killing and preservation. Since circumstances exist where it is not possible to rear maggots, methods of killing and preservation can be vital to preserving the integrity of entomological evidence. In this study, a number of preservation techniques used at crime scenes and in mortuaries were examined, and their effect on feeding third-instar larvae of Calliphora augur and Lucilia cuprina evaluated. The preservatives used were 70, 75, 80, 90 and 100% EtOH, Kahle's solution and 10% formalin. Each treatment was replicated three times. The effect of handling on first- and second-instar, feeding and post-feeding third-instar larvae of C. augur was also examined and compared to unhandled controls. Finally, the effects of preservatives were noted when larvae of C. augur and L. cuprina were placed into preservatives alive. It was found that continued handling is detrimental to specimens because preservative evaporates from both the vial and the specimens. No single preservative type was found to be entirely suitable for both species if DNA retrieval is desired. Specimens placed into most preservatives alive exhibited adverse colour changes, desiccation, sunkeness and agglomeration. It is concluded that the reaction to preservative type might be species specific and that different instars of the same species might also react differently. PMID:18514451

  10. Effect of preservative solutions on preservation of Calliphora augur and Lucilia cuprina larvae (Diptera: Calliphoridae) with implications for post-mortem interval estimates.

    PubMed

    Day, Donnah M; Wallman, James F

    2008-07-18

    A major role of forensic entomology is to estimate the post-mortem interval. An entomologist's estimate of post-mortem interval is based on a series of generally valid assumptions, error in any of which can alter the accuracy of an estimate. The initial process of collecting and preserving maggots can itself lead to error, as can the method of killing and preservation. Since circumstances exist where it is not possible to rear maggots, methods of killing and preservation can be vital to preserving the integrity of entomological evidence. In this study, a number of preservation techniques used at crime scenes and in mortuaries were examined, and their effect on feeding third-instar larvae of Calliphora augur and Lucilia cuprina evaluated. The preservatives used were 70, 75, 80, 90 and 100% EtOH, Kahle's solution and 10% formalin. Each treatment was replicated three times. The effect of handling on first- and second-instar, feeding and post-feeding third-instar larvae of C. augur was also examined and compared to unhandled controls. Finally, the effects of preservatives were noted when larvae of C. augur and L. cuprina were placed into preservatives alive. It was found that continued handling is detrimental to specimens because preservative evaporates from both the vial and the specimens. No single preservative type was found to be entirely suitable for both species if DNA retrieval is desired. Specimens placed into most preservatives alive exhibited adverse colour changes, desiccation, sunkeness and agglomeration. It is concluded that the reaction to preservative type might be species specific and that different instars of the same species might also react differently.

  11. Multilevel, discrete, point-interval data can predict bioattenuation`s potential

    SciTech Connect

    Kabis, T.W.

    1996-05-01

    Closely spaced, discrete-interval groundwater sampling is critical for monitoring aqueous-phase contaminants at hazardous waste sites. Data obtained from discrete-interval sampling devices accurately represent horizontal and vertical extants of contaminant plumes. Discrete point-interval groundwater sampling has been tested in various applications, including natural- and forced-gradient tracer tests plume delineation, and in identifying discrete zones of microbial activity and vertical chemical gradients within an aquifer. An increasingly popular strategy is to avoid active remediation in favor of natural, in-situ attenuation processes. Evaluation of natural attenuation, particularly in-situ bioremediation resulting from multiple terminal electron acceptors, requires site-specific data. Here, multilevel, discrete, point-interval groundwater sampling data is critical. Because groundwater samples from standard monitoring wells often are derived from large vertical sampling zones, the resulting data presents a smeared picture of chemical-microbial conditions; moreover, the potential for natural in-situ bioattenuation can be under- or overestimated without multilevel, discrete, point-interval data. Discrete, point-interval samplers provide a sound basis for evaluating remediation options. One potential obstacle has been the lack of a multipurpose, cost-effective sampler that is operational under a variety of field conditions.

  12. Effects of sampling conditions on DNA-based estimates of American black bear abundance

    USGS Publications Warehouse

    Laufenberg, Jared S.; Van Manen, Frank T.; Clark, Joseph D.

    2013-01-01

    DNA-based capture-mark-recapture techniques are commonly used to estimate American black bear (Ursus americanus) population abundance (N). Although the technique is well established, many questions remain regarding study design. In particular, relationships among N, capture probability of heterogeneity mixtures A and B (pA and pB, respectively, or p, collectively), the proportion of each mixture (π), number of capture occasions (k), and probability of obtaining reliable estimates of N are not fully understood. We investigated these relationships using 1) an empirical dataset of DNA samples for which true N was unknown and 2) simulated datasets with known properties that represented a broader array of sampling conditions. For the empirical data analysis, we used the full closed population with heterogeneity data type in Program MARK to estimate N for a black bear population in Great Smoky Mountains National Park, Tennessee. We systematically reduced the number of those samples used in the analysis to evaluate the effect that changes in capture probabilities may have on parameter estimates. Model-averaged N for females and males were 161 (95% CI = 114–272) and 100 (95% CI = 74–167), respectively (pooled N = 261, 95% CI = 192–419), and the average weekly p was 0.09 for females and 0.12 for males. When we reduced the number of samples of the empirical data, support for heterogeneity models decreased. For the simulation analysis, we generated capture data with individual heterogeneity covering a range of sampling conditions commonly encountered in DNA-based capture-mark-recapture studies and examined the relationships between those conditions and accuracy (i.e., probability of obtaining an estimated N that is within 20% of true N), coverage (i.e., probability that 95% confidence interval includes true N), and precision (i.e., probability of obtaining a coefficient of variation ≤20%) of estimates using logistic regression. The capture probability

  13. Effects of temporal laser profile on the emission spectra for underwater laser-induced breakdown spectroscopy: Study by short-interval double pulses with different pulse durations

    SciTech Connect

    Tamura, Ayaka Matsumoto, Ayumu; Nishi, Naoya; Sakka, Tetsuo; Nakajima, Takashi; Ogata, Yukio H.; Fukami, Kazuhiro

    2015-01-14

    We investigate the effects of temporal laser profile on the emission spectra of laser ablation plasma in water. We use short-interval (76 ns) double pulses with different pulse durations of the composing two pulses for the irradiation of underwater target. Narrow atomic spectral lines in emission spectra are obtained by the irradiation, where the two pulses are wide enough to be merged into a single-pulse-like temporal profile, while deformed spectra are obtained when the two pulses are fully separated. The behavior of the atomic spectral lines for the different pulse durations is consistent with that of the temporal profiles of the optical emission intensities of the plasma. All these results suggest that continuous excitation of the plasma during the laser irradiation for ∼100 ns is a key to obtain narrow emission spectral lines.

  14. Effects of Satellite Sampling Configurations on Derived Gridded Fields

    NASA Technical Reports Server (NTRS)

    Lait, Leslie R.

    1998-01-01

    Various configurations of a scanning satellite instrument are simulated by sampling realistic fields of nitrous oxide. Synoptic grids are computed from the resulting simulated orbital data and compared to the original sampled data fields. Results are compared with those obtained by flying a simulated satellite over low-resolution fields and fields that are static in time. Although increasing the number of instrument scan positions does provide more information along an orbital swath, using more than three to five scan positions does not significantly increase the accuracy of global synoptic grids using the gridding techniques described here.

  15. Invertebrate bioassays with North Sea water samples. I. Structural effects on embryos and larvae of serpulids, oysters and sea urchins

    NASA Astrophysics Data System (ADS)

    Klöckner, K.; Rosenthal, H.; Willführ, J.

    1985-03-01

    Structural effects of bottom and surface water samples from two dumping grounds in the inner German Bight on the development of three meroplanktonic organisms (Pomatoceros triqueter: Polychaeta, Psammechinus miliaris: Echinodermata and Crassostrea gigas, Mollusca) were investigated. The titaniumdioxide dumping site was sampled immediately after dumping (within the visible waste trail 1 km behind the vessel), and 10 h after dumping. Samples were taken in the sewage sludge deposition area in the intervals between the usual dumping activities, regardless of the exact dumping schedule. The preserved bioassay test organisms were inspected microscopically to count percentages of “normal” larval hatch in test water samples, reference water samples and laboratory aged control water samples (5 to 10 replicates). The relative water quality at various dumping sites was expressed in terms of “net risk”-values (Woelke, 1972) compared to hatching rates observed in the controls. Larval development of P. triqueter was significantly suppressed (up to -22 % “net risk”) in trail water of the titanium dioxide dump site while the development of sea urchin larvae was still affected in the 10 h surface samples. Hatching of all test organisms in bottom-water samples from the centre of the sewage sludge dump site was affected to different degrees when compared to reference areas about 4 km north or 6 km northwest of the dumping area. The general usefulness of standardized bioassay procedures in pollution monitoring programmes is discussed. The results presented here call for further verification to minimize experimental background variability and to enlarge the catalogue of suitable effects criteria.

  16. Constructing Confidence Intervals for Qtl Location

    PubMed Central

    Mangin, B.; Goffinet, B.; Rebai, A.

    1994-01-01

    We describe a method for constructing the confidence interval of the QTL location parameter. This method is developed in the local asymptotic framework, leading to a linear model at each position of the putative QTL. The idea is to construct a likelihood ratio test, using statistics whose asymptotic distribution does not depend on the nuisance parameters and in particular on the effect of the QTL. We show theoretical properties of the confidence interval built with this test, and compare it with the classical confidence interval using simulations. We show in particular, that our confidence interval has the correct probability of containing the true map location of the QTL, for almost all QTLs, whereas the classical confidence interval can be very biased for QTLs having small effect. PMID:7896108

  17. On the Effect of Preferential Sampling in Spatial Prediction

    EPA Science Inventory

    The choice of the sampling locations in a spatial network is often guided by practical demands. In particular, typically, locations are preferentially chosen to capture high values of a response, for example, air pollution levels in environmental monitoring. Then, model estimatio...

  18. A MORE COST-EFFECTIVE EMAP BENTHIC MACROFAUNAL SAMPLING PROTOCOL

    EPA Science Inventory

    Benthic macrofaunal sampling protocols in the U.S. Environmental Protection Agency's Environmental Monitoring and Assessment Program (EMAP) are to collect 30 to 50 random benthic macrofauna [defined as animals retained on a 0.5 mm (East and Gulf Coasts, USA) or a 1.0 mm mesh siev...

  19. POREWATER CHEMISTRY: EFFECTS OF SAMPLING, STORAGE, HANDLING, AND TOXICITY TESTING

    EPA Science Inventory

    As a general principle, it is nearly impossible to remove a porewater sample from sediment, use it in a toxicity testing vessel with test organisms, and prevent changes in the chemistry of the natural and anthropogenic organic and inorganic constituents. The degree of change in t...

  20. Hydrodynamic effects in buccal cell DNA sample collection

    NASA Astrophysics Data System (ADS)

    Aidun, C. K.; Sozer, A. C.

    2003-11-01

    Many different methods can be used for collection of biological samples from individuals for DNA profiling purposes. However, blood and buccal cells are the two most popular sources of DNA. In situations where large numbers of samples have to be collected, buccal cell collection methods are the preferred choice because of minimized health risks and ease of collection, transportation, and storage. The normal practice in buccal cell collection is to rub a cotton swab or a piece of paper through the inner check of the subject in order to release the cells and to attach and collect the cells on the cotton or paper fibers. The problem with the current forms of sample collection and storage is that in some cases up to 20% of the samples collected do not result in a DNA profile of adequate quality to be reported by the laboratory without repeated testing. In this study, we consider the mechanics of a small sheet of paper being rubbed on the surface of the inner check. The process is not too different from coating a paper substrate with highly deformable material. The shear field developed between the paper and the fluid adjacent to the cells are estimated based on the available data. The action of the cell release and the cell adherence to the surface will be outlined.

  1. Sampling Development

    ERIC Educational Resources Information Center

    Adolph, Karen E.; Robinson, Scott R.

    2011-01-01

    Research in developmental psychology requires sampling at different time points. Accurate depictions of developmental change provide a foundation for further empirical studies and theories about developmental mechanisms. However, overreliance on widely spaced sampling intervals in cross-sectional and longitudinal designs threatens the validity of…

  2. Reference intervals for serum creatine kinase in athletes

    PubMed Central

    Mougios, Vassilis

    2007-01-01

    Background The serum concentration of creatine kinase (CK) is used widely as an index of skeletal muscle fibre damage in sport and exercise. Since athletes have higher CK values than non‐athletes, comparing the values of athletes to the normal values established in non‐athletes is pointless. The purpose of this study was to introduce reference intervals for CK in athletes. Method CK was assayed in serum samples from 483 male athletes and 245 female athletes, aged 7–44. Samples had been obtained throughout the training and competition period. For comparison, CK was also assayed in a smaller number of non‐athletes. Reference intervals (2.5th to 97.5th percentile) were calculated by the non‐parametric method. Results The reference intervals were 82–1083 U/L (37°C) in male and 47–513 U/L in female athletes. The upper reference limits were twice the limits reported for moderately active non‐athletes in the literature or calculated in the non‐athletes in this study. The upper limits were up to six times higher than the limits reported for inactive individuals in the literature. When reference intervals were calculated specifically in male football (soccer) players and swimmers, a threefold difference in the upper reference limit was found (1492 vs 523 U/L, respectively), probably resulting from the different training and competition demands of the two sports. Conclusion Sport training and competition have profound effects on the reference intervals for serum CK. Introducing sport‐specific reference intervals may help to avoid misinterpretation of high values and to optimise training. PMID:17526622

  3. Effect of crucible?sample adhesion on grain germination

    NASA Astrophysics Data System (ADS)

    Duffar, T.; Dusserre, P.; Giacometti, N.; Boiton, P.; Nabot, J. P.; Eustathopoulos, N.

    1999-03-01

    Solid-liquid interface demarcations have been performed during the growth of GaSb and Ge samples by the vertical Bridgman method. The crucibles were made of boron nitride, silica or carbon based materials. Subsequent metallographies in a plane containing the sample axis show that the interface is distorted on a distance of about 100 μm close to the crucible wall. The angle of the interface line with the crucible, measured on the solid side, ranges between 25° for GaSb/BN to 120° for Ge/SiO 2. These measures are compared to the experimental observation that parasitic grain nucleation has a high probability of occurrence when BN crucibles are used and a rather low one in the case of silica crucibles. These results are in qualitative agreement with the theory of nucleation on homogeneous or heterogeneous substrates.

  4. The effect of acute and chronic sprint-interval training on LRP130, SIRT3, and PGC-1α expression in human skeletal muscle.

    PubMed

    Edgett, Brittany A; Bonafiglia, Jacob T; Baechler, Brittany L; Quadrilatero, Joe; Gurd, Brendon J

    2016-09-01

    This study examined changes in LRP130 gene and protein expression in response to an acute bout of sprint-interval training (SIT) and 6 weeks of SIT in human skeletal muscle. In addition, we investigated the relationships between changes in LRP130, SIRT3, and PGC-1α gene or protein expression. Fourteen recreationally active men (age: 22.0 ± 2.4 years) performed a single bout of SIT (eight, 20-sec intervals at ~170% of VO2peak work rate, separated by 10 sec of rest). Muscle biopsies were obtained at rest (PRE) and 3 h post-exercise. The same participants then underwent a 6 week SIT program with biopsies after 2 (MID) and 6 (POST) weeks of training. In response to an acute bout of SIT, PGC-1α mRNA expression increased (284%, P < 0.001); however, LRP130 and SIRT3 remained unchanged. VO2peak and fiber-specific SDH activity increased in response to training (P < 0.01). LRP130, SIRT3, and PGC-1α protein expression were also unaltered following 2 and 6 weeks of SIT There were no significant correlations between LRP130, SIRT3, or PGC-1α mRNA expression in response to acute SIT However, changes in protein expression of LRP130, SIRT3, and PGC-1α were positively correlated at several time points with large effect sizes, which suggest that the regulation of these proteins may be coordinated in human skeletal muscle. Future studies should investigate other exercise protocols known to increase PGC-1α and SIRT3 protein, like longer duration steady-state exercise, to identify if LRP130 expression can be altered in response to exercise. PMID:27604398

  5. Effects of short deprivation and re-exposure intervals on the ethanol drinking behavior of selectively bred high alcohol-consuming rats.

    PubMed

    Bell, Richard L; Rodd, Zachary A; Schultz, Jonathon A; Peper, Caron L; Lumeng, Lawrence; Murphy, James M; McBride, William J

    2008-08-01

    Alcoholics generally display cycles of excessive ethanol intake, abstinence and relapse behavior. Using an animal model of relapse-like drinking, the alcohol deprivation effect (ADE), our laboratory has shown that repeated 2-week cycles of ethanol deprivation and re-exposure, following an initial 6-week access period, result in a robust ADE by alcohol-preferring (P) and high alcohol-drinking (HAD-1 and HAD-2) rats. These rat lines have been selectively bred to prefer a 10% ethanol solution over water. The present study examined whether P and HAD rats would display an ADE using much shorter ethanol deprivation and re-exposure intervals. Rats were given either continuous or periodic concurrent access to multiple concentrations (10%, 20%, and 30% [vol/vol]) of ethanol. The periodic protocol involved access to ethanol for 12 days followed by four cycles of 4 days of deprivation and 4 days of re-exposure to ethanol access. High-alcohol-drinking rats displayed a robust 24-h ADE upon first re-exposure (HAD-1: approximately 5 vs. 8g/kg/day; HAD-2: approximately 6 vs. 9g/kg/day, baseline vs. re-exposure), whereas P rats ( approximately 7 vs. 8g/kg/day) displayed a modest, nonsignificant, increase in 24-h intake. In a separate group of rats, ethanol intake and blood alcohol concentrations after the first hour of the fourth re-exposure cycle were HAD-1: 2.0g/kg and 97 mg%, HAD-2: 2.3g/kg and 73 mg%, and P: 1.2g/kg and 71 mg%; with all three lines displaying a robust first hour ADE. These findings suggest that (a) an ADE may be observed with short ethanol deprivation and re-exposure intervals in HAD rats, and (b) the genetic make-up of the P and HAD rats influences the expression of this ADE.

  6. Effects of aerobic interval training and continuous training on cellular markers of endothelial integrity in coronary artery disease: a SAINTEX-CAD substudy.

    PubMed

    Van Craenenbroeck, Emeline M; Frederix, Geert; Pattyn, Nele; Beckers, Paul; Van Craenenbroeck, Amaryllis H; Gevaert, Andreas; Possemiers, Nadine; Cornelissen, Veronique; Goetschalckx, Kaatje; Vrints, Christiaan J; Vanhees, Luc; Hoymans, Vicky Y

    2015-12-01

    In this large multicenter trial, we aimed to assess the effect of aerobic exercise training in stable coronary artery disease (CAD) patients on cellular markers of endothelial integrity and to examine their relation with improvement of endothelial function. Two-hundred CAD patients (left ventricular ejection fraction > 40%, 90% male, mean age 58.4 ± 9.1 yr) were randomized on a 1:1 base to a supervised 12-wk rehabilitation program of either aerobic interval training or aerobic continuous training on a bicycle. At baseline and after 12 wk, numbers of circulating CD34(+)/KDR(+)/CD45dim endothelial progenitor cells (EPCs), CD31(+)/CD3(+)/CXCR4(+) angiogenic T cells, and CD31(+)/CD42b(-) endothelial microparticles (EMPs) were analyzed by flow cytometry. Endothelial function was assessed by flow-mediated dilation (FMD) of the brachial artery. After 12 wk of aerobic interval training or aerobic continuous training, numbers of circulating EPCs, angiogenic T cells, and EMPs were comparable with baseline levels. Whereas improvement in peak oxygen consumption was correlated to improvement in FMD (Pearson r = 0.17, P = 0.035), a direct correlation of baseline or posttraining EPCs, angiogenic T cells, and EMP levels with FMD was absent. Baseline EMPs related inversely to the magnitude of the increases in peak oxygen consumption (Spearman rho = -0.245, P = 0.027) and FMD (Spearman rho = -0.374, P = 0.001) following exercise training. In conclusion, endothelial function improvement in response to exercise training in patients with CAD did not relate to altered levels of EPCs and angiogenic T cells and/or a diminished shedding of EMPs into the circulation. EMP flow cytometry may be predictive of the increase in aerobic capacity and endothelial function.

  7. Effects of aerobic interval training and continuous training on cellular markers of endothelial integrity in coronary artery disease: a SAINTEX-CAD substudy.

    PubMed

    Van Craenenbroeck, Emeline M; Frederix, Geert; Pattyn, Nele; Beckers, Paul; Van Craenenbroeck, Amaryllis H; Gevaert, Andreas; Possemiers, Nadine; Cornelissen, Veronique; Goetschalckx, Kaatje; Vrints, Christiaan J; Vanhees, Luc; Hoymans, Vicky Y

    2015-12-01

    In this large multicenter trial, we aimed to assess the effect of aerobic exercise training in stable coronary artery disease (CAD) patients on cellular markers of endothelial integrity and to examine their relation with improvement of endothelial function. Two-hundred CAD patients (left ventricular ejection fraction > 40%, 90% male, mean age 58.4 ± 9.1 yr) were randomized on a 1:1 base to a supervised 12-wk rehabilitation program of either aerobic interval training or aerobic continuous training on a bicycle. At baseline and after 12 wk, numbers of circulating CD34(+)/KDR(+)/CD45dim endothelial progenitor cells (EPCs), CD31(+)/CD3(+)/CXCR4(+) angiogenic T cells, and CD31(+)/CD42b(-) endothelial microparticles (EMPs) were analyzed by flow cytometry. Endothelial function was assessed by flow-mediated dilation (FMD) of the brachial artery. After 12 wk of aerobic interval training or aerobic continuous training, numbers of circulating EPCs, angiogenic T cells, and EMPs were comparable with baseline levels. Whereas improvement in peak oxygen consumption was correlated to improvement in FMD (Pearson r = 0.17, P = 0.035), a direct correlation of baseline or posttraining EPCs, angiogenic T cells, and EMP levels with FMD was absent. Baseline EMPs related inversely to the magnitude of the increases in peak oxygen consumption (Spearman rho = -0.245, P = 0.027) and FMD (Spearman rho = -0.374, P = 0.001) following exercise training. In conclusion, endothelial function improvement in response to exercise training in patients with CAD did not relate to altered levels of EPCs and angiogenic T cells and/or a diminished shedding of EMPs into the circulation. EMP flow cytometry may be predictive of the increase in aerobic capacity and endothelial function. PMID:26453327

  8. Effects of the New Aldose Reductase Inhibitor Benzofuroxane Derivative BF-5m on High Glucose Induced Prolongation of Cardiac QT Interval and Increase of Coronary Perfusion Pressure

    PubMed Central

    Di Filippo, C.; Ferraro, B.; Maisto, R.; Trotta, M. C.; Di Carluccio, N.; Sartini, S.; La Motta, C.; Ferraraccio, F.; Rossi, F.; D'Amico, M.

    2016-01-01

    This study investigated the effects of the new aldose reductase inhibitor benzofuroxane derivative 5(6)-(benzo[d]thiazol-2-ylmethoxy)benzofuroxane (BF-5m) on the prolongation of cardiac QT interval and increase of coronary perfusion pressure (CPP) in isolated, high glucose (33.3 mM D-glucose) perfused rat hearts. BF-5m was dissolved in the Krebs solution at a final concentration of 0.01 μM, 0.05 μM, and 0.1 μM. 33.3 mM D-glucose caused a prolongation of the QT interval and increase of CPP up to values of 190 ± 12 ms and 110 ± 8 mmHg with respect to the values of hearts perfused with standard Krebs solution (11.1 mM D-glucose). The QT prolongation was reduced by 10%, 32%, and 41%, respectively, for the concentration of BF-5m 0.01 μM, 0.05 μM, and 0.1 μM. Similarly, the CPP was reduced by 20% for BF-5m 0.05 μM and by 32% for BF-5m 0.1 μM. BF-5m also increased the expression levels of sirtuin 1, MnSOD, eNOS, and FOXO-1, into the heart. The beneficial actions of BF-5m were partly abolished by the pretreatment of the rats with the inhibitor of the sirtuin 1 activity EX527 (10 mg/kg/day/7 days i.p.) prior to perfusion of the hearts with high glucose + BF-5m (0.1 μM). Therefore, BF-5m supplies cardioprotection from the high glucose induced QT prolongation and increase of CPP. PMID:26839893

  9. Uncertainty in nutrient loads from tile-drained landscapes: Effect of sampling frequency, calculation algorithm, and compositing strategy

    NASA Astrophysics Data System (ADS)

    Williams, Mark R.; King, Kevin W.; Macrae, Merrin L.; Ford, William; Van Esbroeck, Chris; Brunke, Richard I.; English, Michael C.; Schiff, Sherry L.

    2015-11-01

    Accurate estimates of annual nutrient loads are required to evaluate trends in water quality following changes in land use or management and to calibrate and validate water quality models. While much emphasis has been placed on understanding the uncertainty of nutrient load estimates in large, naturally drained watersheds, few studies have focused on tile-drained fields and small tile-drained headwater watersheds. The objective of this study was to quantify uncertainty in annual dissolved reactive phosphorus (DRP) and nitrate-nitrogen (NO3-N) load estimates from four tile-drained fields and two small tile-drained headwater watersheds in Ohio, USA and Ontario, Canada. High temporal resolution datasets of discharge (10-30 min) and nutrient concentration (2 h to 1 d) were collected over a 1-2 year period at each site and used to calculate a reference nutrient load. Monte Carlo simulations were used to subsample the measured data to assess the effects of sample frequency, calculation algorithm, and compositing strategy on the uncertainty of load estimates. Results showed that uncertainty in annual DRP and NO3-N load estimates was influenced by both the sampling interval and the load estimation algorithm. Uncertainty in annual nutrient load estimates increased with increasing sampling interval for all of the load estimation algorithms tested. Continuous discharge measurements and linear interpolation of nutrient concentrations yielded the least amount of uncertainty, but still tended to underestimate the reference load. Compositing strategies generally improved the precision of load estimates compared to discrete grab samples; however, they often reduced the accuracy. Based on the results of this study, we recommended that nutrient concentration be measured every 13-26 h for DRP and every 2.7-17.5 d for NO3-N in tile-drained fields and small tile-drained headwater watersheds to accurately (±10%) estimate annual loads.

  10. Multichannel interval timer (MINT)

    SciTech Connect

    Kimball, K.B.

    1982-06-01

    A prototype Multichannel INterval Timer (MINT) has been built for measuring signal Time of Arrival (TOA) from sensors placed in blast environments. The MINT is intended to reduce the space, equipment costs, and data reduction efforts associated with traditional analog TOA recording methods, making it more practical to field the large arrays of TOA sensors required to characterize blast environments. This document describes the MINT design features, provides the information required for installing and operating the system, and presents proposed improvements for the next generation system.

  11. Interval-valued random functions and the kriging of intervals

    SciTech Connect

    Diamond, P.

    1988-04-01

    Estimation procedures using data that include some values known to lie within certain intervals are usually regarded as problems of constrained optimization. A different approach is used here. Intervals are treated as elements of a positive cone, obeying the arithmetic of interval analysis, and positive interval-valued random functions are discussed. A kriging formalism for interval-valued data is developed. It provides estimates that are themselves intervals. In this context, the condition that kriging weights be positive is seen to arise in a natural way. A numerical example is given, and the extension to universal kriging is sketched.

  12. Molecular fluorescence analysis of rainwater: effects of sample preservation.

    PubMed

    Santos, Patrícia S M; Otero, Marta; Santos, Eduarda B H; Duarte, Armando C

    2010-09-15

    Very different filtration and preservation procedures may be found in the literature on the study of the rainwater dissolved organic fraction. Thus, the influence of sample filtration and preservation procedures on the fluorescence of rainwater dissolved organic matter (DOM) was studied in this work. Rainwater was filtered through different filters (quartz 0.22 microm or PVDF 0.45 microm) and excitation (lambda(em)=415 nm) and synchronous (Deltalambda=70 nm) fluorescence spectra were obtained at the same day of collection, or after preservation by refrigeration (1-7 days) or by freezing (1-4 weeks). The excitation-emission matrix (EEM) spectra of rainwater showed six types of fluorescent bands: two corresponding to humic-like bands, and four resembling proteins. Then, the excitation and synchronous spectra were chosen in order to monitor changes in the humic-like and protein-like bands, respectively. The filtration procedures adopted in this work did not affect the fluorescence properties of the rainwater samples. However, these properties were differently preserved by refrigeration or freezing: after refrigeration, filtered rainwater maintained the original fluorescent properties for at least 4 days, while after freezing fluorescent properties were not always preserved since it occurred a decrease of protein-like fluorescence intensity.

  13. Measurements of Shock Effects Recorded by Hayabusa Samples

    NASA Technical Reports Server (NTRS)

    Zolensky, Michael; Mikouchi, Takashi; Hagiya, Kenji; Ohsumi, Kazumasa; Martinez, James; Komatsu, Mutsumi; Chan, Queenie H-.S.

    2015-01-01

    We requested and have been approved for 5 Hayabusa samples in order definitively establish the degree of shock experienced by the regolith of asteroid Itokawa, and to devise a bridge between shock determinations by standard light optical petrography, crystal structures as determined by synchrotron X-ray diffraction (SXRD), and degree of crystallinity as determined by electron back-scattered diffraction (EBSD) [1,2]. As of the writing of this abstract we are awaiting the approved samples. We propose measurements of astromaterial crystal structures and regolith processes. The proposed research work will improve our understanding of how small, primitive solar system bodies formed and evolved, and improve understanding of the processes that determine the history and future of habitability of environments on other solar system bodies. The results of the proposed research will directly enrich the ongoing asteroid and comet exploration missions by NASA, JAXA and ESA, and broaden our understanding of the origin and evolution of small bodies in the early solar system, and elucidate the nature of asteroid and comet regolith.

  14. Measurements of Shock Effects Recorded by Itokawa Samples

    NASA Technical Reports Server (NTRS)

    Zolensky, Michael; Mikouchi, Takashi; Hagiya, Kenji; Ohsumi, Kazumasa; Martinez, James; Komatsu, Mutsumi; Chan, Queenie H-.S.

    2016-01-01

    We requested and have been approved for 5 Hayabusa samples in order definitively establish the degree of shock experienced by the regolith of asteroid Itokawa, and to devise a bridge between shock determinations by standard light optical petrography, crystal structures as determined by synchrotron X-ray diffraction (SXRD), and degree of crystallinity as determined by electron back-scattered diffraction (EBSD). As of the writing of this abstract we are awaiting the approved samples. We propose measurements of astromaterial crystal structures and regolith processes. The proposed research work will improve our understanding of how small, primitive solar system bodies formed and evolved, and improve understanding of the processes that determine the history and future of habitability of environments on other solar system bodies. The results of the proposed research will directly enrich the ongoing asteroid and comet exploration missions by NASA, JAXA and ESA, and broaden our understanding of the origin and evolution of small bodies in the early solar system, and elucidate the nature of asteroid and comet regolith.

  15. Mass spectrometer with electron source for reducing space charge effects in sample beam

    DOEpatents

    Houk, Robert S.; Praphairaksit, Narong

    2003-10-14

    A mass spectrometer includes an ion source which generates a beam including positive ions, a sampling interface which extracts a portion of the beam from the ion source to form a sample beam that travels along a path and has an excess of positive ions over at least part of the path, thereby causing space charge effects to occur in the sample beam due to the excess of positive ions in the sample beam, an electron source which adds electrons to the sample beam to reduce space charge repulsion between the positive ions in the sample beam, thereby reducing the space charge effects in the sample beam and producing a sample beam having reduced space charge effects, and a mass analyzer which analyzes the sample beam having reduced space charge effects.

  16. Effects of High Intensity Interval versus Moderate Continuous Training on Markers of Ventilatory and Cardiac Efficiency in Coronary Heart Disease Patients

    PubMed Central

    Cardozo, Gustavo G.; Oliveira, Ricardo B.; Farinatti, Paulo T. V.

    2015-01-01

    Background. We tested the hypothesis that high intensity interval training (HIIT) would be more effective than moderate intensity continuous training (MIT) to improve newly emerged markers of cardiorespiratory fitness in coronary heart disease (CHD) patients, as the relationship between ventilation and carbon dioxide production (VE/VCO2 slope), oxygen uptake efficiency slope (OUES), and oxygen pulse (O2P). Methods. Seventy-one patients with optimized treatment were randomly assigned into HIIT (n = 23, age = 56 ± 12 years), MIT (n = 24, age = 62 ± 12 years), or nonexercise control group (CG) (n = 24, age = 64 ± 12 years). MIT performed 30 min of continuous aerobic exercise at 70–75% of maximal heart rate (HRmax), and HIIT performed 30 min sessions split in 2 min alternate bouts at 60%/90% HRmax (3 times/week for 16 weeks). Results. No differences among groups (before versus after) were found for VE/VCO2 slope or OUES (P > 0.05). After training the O2P slope increased in HIIT (22%, P < 0.05) but not in MIT (2%, P > 0.05), while decreased in CG (−20%, P < 0.05) becoming lower versus HIIT (P = 0.03). Conclusion. HIIT was more effective than MIT for improving O2P slope in CHD patients, while VE/VCO2 slope and OUES were similarly improved by aerobic training regimens versus controls. PMID:25741531

  17. Pigeons' choices between fixed-interval and random-interval schedules: utility of variability?

    PubMed

    Andrzejewski, Matthew E; Cardinal, Claudia D; Field, Douglas P; Flannery, Barbara A; Johnson, Michael; Bailey, Kathleen; Hineline, Philip N

    2005-03-01

    Pigeons' choosing between fixed-interval and random-interval schedules of reinforcement was investigated in three experiments using a discrete-trial procedure. In all three experiments, the random-interval schedule was generated by sampling a probability distribution at an interval (and in multiples of the interval) equal to that of the fixed-interval schedule. Thus the programmed delays to reinforcement on the random alternative were never shorter and were often longer than the fixed interval. Despite this feature, the fixed schedule was not strongl