Non-spatial pre-training in the water maze as a clinically relevant model for evaluating learning and memory in experimental TBI.

Science.gov (United States)

Wagner, Amy K; Brayer, Samuel W; Hurwitz, Max; Niyonkuru, Christian; Zou, Huichao; Failla, Michelle; Arenth, Patricia; Manole, Mioara D; Skidmore, Elizabeth; Thiels, Edda

2013-11-01

Explicit and implicit learning and memory networks exist where each network can facilitate or inhibit cognition. Clinical evidence suggests that implicit networks are relatively preserved after traumatic brain injury (TBI). Non-spatial pre-training (NSPT) in the Morris Water Maze (MWM) provides the necessary behavioral components to complete the task, while limiting the formation of spatial maps. Our study utilized NSPT in the MWM to assess implicit and explicit learning and memory system deficits in the controlled cortical impact (CCI) model of TBI. 76 adult male Sprague-Dawley rats were divided: CCI vs. sham surgery, NSPT vs. No-NSPT, and cued vs. non-cued groups. NSPT occurred for 4d prior to surgery (dynamic hidden platform location, extra-maze cues covered, static pool entry point). Acquisition (d14-18), Probe/Visible Platform (d19), and Reversal (d20-21) trials were conducted with or without extra-maze cues. Novel time allocation and search strategy selection metrics were utilized. Results indicated implicit and explicit learning/memory networks are distinguishable in the MWM. In the cued condition, NSPT reduced thigmotaxis, improved place learning, and largely eliminated the apparent injury-induced deficits typically observed between untrained CCI and sham rats. However, among NSPT groups, incorporation of cues into search strategy selection for CCI rats was relatively impaired compared to shams. Non-cued condition performance showed sham/NSPT and CCI/NSPT rats perform similarly, suggesting implicit memory networks are largely intact 2weeks after CCI. Place learning differences between CCI/NSPT and sham/NSPT rats more accurately reflect spatial deficits in our CCI model compared to untrained controls. These data suggest NSPT as a clinically relevant construct for evaluating potential neurorestorative and neuroprotective therapies. These findings also support development of non-spatial cognitive training paradigms for evaluating rehabilitation relevant

Differential Recruitment of Parietal Cortex during Spatial and Non-spatial Reach Planning

Directory of Open Access Journals (Sweden)

Pierre-Michel Bernier

2017-05-01

Full Text Available The planning of goal-directed arm reaching movements is associated with activity in the dorsal parieto-frontal cortex, within which multiple regions subserve the integration of arm- and target-related sensory signals to encode a motor goal. Surprisingly, many of these regions show sustained activity during reach preparation even when target location is not specified, i.e., when a motor goal cannot be unambiguously formed. The functional role of these non-spatial preparatory signals remains unresolved. Here this process was investigated in humans by comparing reach preparatory activity in the presence or absence of information regarding upcoming target location. In order to isolate the processes specific to reaching and to control for visuospatial attentional factors, the reaching task was contrasted to a finger movement task. Functional MRI and electroencephalography (EEG were used to characterize the spatio-temporal pattern of reach-related activity in the parieto-frontal cortex. Reach planning with advance knowledge of target location induced robust blood oxygenated level dependent and EEG responses across parietal and premotor regions contralateral to the reaching arm. In contrast, reach preparation without knowledge of target location was associated with a significant BOLD response bilaterally in the parietal cortex. Furthermore, EEG alpha- and beta-band activity was restricted to parietal scalp sites, the magnitude of the latter being correlated with reach reaction times. These results suggest an intermediate stage of sensorimotor transformations in bilateral parietal cortex when target location is not specified.

Caffeine plus nicotine improves motor function, spatial and non-spatial working memory and functional indices in BALB/c male mice.

Science.gov (United States)

Adeniyi, P A; Omatsuli, E P; Akinyemi, A J; Ishola, A O

2016-12-01

There is a greater prevalence of cigarette smoking among caffeine dependent individuals. This study therefore sought to assess the effect of nicotine and/or caffeine on some key biochemical indices and neurobehavioural parameters associated with brain function in male mice. Forty male BALB/c mice were divided into 4 groups of 10 animals each; Group A serve as the control and received normal saline (s.c), Group B received 2mg/kg body weight of nicotine (s.c), Group C received 2mg/kg body weight of caffeine (s.c) and Group D received 2mg/kg of nicotine and 2mg/kg of caffeine (s.c). The experiment lasted for 21 days, and then the animals were subjected to behavioral test. Thereafter the animals were sacrificed and their brain isolated for the determination of endothelial nitric oxide (NO) level, acetylcholinesterase (AChE), arginase (Arg) and adenosine deaminase (ADA) activities; as well as some antioxidant indices. Administration of nicotine or caffeine caused a significant (Pcaffeine cognitive properties through a significant increase in non-spatial working memory whereas; it was otherwise on the spatial working memory and motor coordination. Therefore, we can suggest from our present study that caffeine enhances the effect of nicotine either synergistically or additively on memory and motor function and some key biochemical indices associated with brain function in male mice. Copyright © 2016. Published by Elsevier B.V.

Survival behavior in the cyclic Lotka-Volterra model with a randomly switching reaction rate.

Science.gov (United States)

West, Robert; Mobilia, Mauro; Rucklidge, Alastair M

2018-02-01

We study the influence of a randomly switching reproduction-predation rate on the survival behavior of the nonspatial cyclic Lotka-Volterra model, also known as the zero-sum rock-paper-scissors game, used to metaphorically describe the cyclic competition between three species. In large and finite populations, demographic fluctuations (internal noise) drive two species to extinction in a finite time, while the species with the smallest reproduction-predation rate is the most likely to be the surviving one (law of the weakest). Here we model environmental (external) noise by assuming that the reproduction-predation rate of the strongest species (the fastest to reproduce and predate) in a given static environment randomly switches between two values corresponding to more and less favorable external conditions. We study the joint effect of environmental and demographic noise on the species survival probabilities and on the mean extinction time. In particular, we investigate whether the survival probabilities follow the law of the weakest and analyze their dependence on the external noise intensity and switching rate. Remarkably, when, on average, there is a finite number of switches prior to extinction, the survival probability of the predator of the species whose reaction rate switches typically varies nonmonotonically with the external noise intensity (with optimal survival about a critical noise strength). We also outline the relationship with the case where all reaction rates switch on markedly different time scales.

Survival behavior in the cyclic Lotka-Volterra model with a randomly switching reaction rate

Science.gov (United States)

West, Robert; Mobilia, Mauro; Rucklidge, Alastair M.

2018-02-01

We study the influence of a randomly switching reproduction-predation rate on the survival behavior of the nonspatial cyclic Lotka-Volterra model, also known as the zero-sum rock-paper-scissors game, used to metaphorically describe the cyclic competition between three species. In large and finite populations, demographic fluctuations (internal noise) drive two species to extinction in a finite time, while the species with the smallest reproduction-predation rate is the most likely to be the surviving one (law of the weakest). Here we model environmental (external) noise by assuming that the reproduction-predation rate of the strongest species (the fastest to reproduce and predate) in a given static environment randomly switches between two values corresponding to more and less favorable external conditions. We study the joint effect of environmental and demographic noise on the species survival probabilities and on the mean extinction time. In particular, we investigate whether the survival probabilities follow the law of the weakest and analyze their dependence on the external noise intensity and switching rate. Remarkably, when, on average, there is a finite number of switches prior to extinction, the survival probability of the predator of the species whose reaction rate switches typically varies nonmonotonically with the external noise intensity (with optimal survival about a critical noise strength). We also outline the relationship with the case where all reaction rates switch on markedly different time scales.

A random effects meta-analysis model with Box-Cox transformation.

Science.gov (United States)

Yamaguchi, Yusuke; Maruo, Kazushi; Partlett, Christopher; Riley, Richard D

2017-07-19

In a random effects meta-analysis model, true treatment effects for each study are routinely assumed to follow a normal distribution. However, normality is a restrictive assumption and the misspecification of the random effects distribution may result in a misleading estimate of overall mean for the treatment effect, an inappropriate quantification of heterogeneity across studies and a wrongly symmetric prediction interval. We focus on problems caused by an inappropriate normality assumption of the random effects distribution, and propose a novel random effects meta-analysis model where a Box-Cox transformation is applied to the observed treatment effect estimates. The proposed model aims to normalise an overall distribution of observed treatment effect estimates, which is sum of the within-study sampling distributions and the random effects distribution. When sampling distributions are approximately normal, non-normality in the overall distribution will be mainly due to the random effects distribution, especially when the between-study variation is large relative to the within-study variation. The Box-Cox transformation addresses this flexibly according to the observed departure from normality. We use a Bayesian approach for estimating parameters in the proposed model, and suggest summarising the meta-analysis results by an overall median, an interquartile range and a prediction interval. The model can be applied for any kind of variables once the treatment effect estimate is defined from the variable. A simulation study suggested that when the overall distribution of treatment effect estimates are skewed, the overall mean and conventional I 2 from the normal random effects model could be inappropriate summaries, and the proposed model helped reduce this issue. We illustrated the proposed model using two examples, which revealed some important differences on summary results, heterogeneity measures and prediction intervals from the normal random effects model. The

A random effects meta-analysis model with Box-Cox transformation

Directory of Open Access Journals (Sweden)

Yusuke Yamaguchi

2017-07-01

Full Text Available Abstract Background In a random effects meta-analysis model, true treatment effects for each study are routinely assumed to follow a normal distribution. However, normality is a restrictive assumption and the misspecification of the random effects distribution may result in a misleading estimate of overall mean for the treatment effect, an inappropriate quantification of heterogeneity across studies and a wrongly symmetric prediction interval. Methods We focus on problems caused by an inappropriate normality assumption of the random effects distribution, and propose a novel random effects meta-analysis model where a Box-Cox transformation is applied to the observed treatment effect estimates. The proposed model aims to normalise an overall distribution of observed treatment effect estimates, which is sum of the within-study sampling distributions and the random effects distribution. When sampling distributions are approximately normal, non-normality in the overall distribution will be mainly due to the random effects distribution, especially when the between-study variation is large relative to the within-study variation. The Box-Cox transformation addresses this flexibly according to the observed departure from normality. We use a Bayesian approach for estimating parameters in the proposed model, and suggest summarising the meta-analysis results by an overall median, an interquartile range and a prediction interval. The model can be applied for any kind of variables once the treatment effect estimate is defined from the variable. Results A simulation study suggested that when the overall distribution of treatment effect estimates are skewed, the overall mean and conventional I 2 from the normal random effects model could be inappropriate summaries, and the proposed model helped reduce this issue. We illustrated the proposed model using two examples, which revealed some important differences on summary results, heterogeneity measures and

Random effects coefficient of determination for mixed and meta-analysis models.

Science.gov (United States)

Demidenko, Eugene; Sargent, James; Onega, Tracy

2012-01-01

The key feature of a mixed model is the presence of random effects. We have developed a coefficient, called the random effects coefficient of determination, [Formula: see text], that estimates the proportion of the conditional variance of the dependent variable explained by random effects. This coefficient takes values from 0 to 1 and indicates how strong the random effects are. The difference from the earlier suggested fixed effects coefficient of determination is emphasized. If [Formula: see text] is close to 0, there is weak support for random effects in the model because the reduction of the variance of the dependent variable due to random effects is small; consequently, random effects may be ignored and the model simplifies to standard linear regression. The value of [Formula: see text] apart from 0 indicates the evidence of the variance reduction in support of the mixed model. If random effects coefficient of determination is close to 1 the variance of random effects is very large and random effects turn into free fixed effects-the model can be estimated using the dummy variable approach. We derive explicit formulas for [Formula: see text] in three special cases: the random intercept model, the growth curve model, and meta-analysis model. Theoretical results are illustrated with three mixed model examples: (1) travel time to the nearest cancer center for women with breast cancer in the U.S., (2) cumulative time watching alcohol related scenes in movies among young U.S. teens, as a risk factor for early drinking onset, and (3) the classic example of the meta-analysis model for combination of 13 studies on tuberculosis vaccine.

Random diffusion and leverage effect in financial markets.

Science.gov (United States)

Perelló, Josep; Masoliver, Jaume

2003-03-01

We prove that Brownian market models with random diffusion coefficients provide an exact measure of the leverage effect [J-P. Bouchaud et al., Phys. Rev. Lett. 87, 228701 (2001)]. This empirical fact asserts that past returns are anticorrelated with future diffusion coefficient. Several models with random diffusion have been suggested but without a quantitative study of the leverage effect. Our analysis lets us to fully estimate all parameters involved and allows a deeper study of correlated random diffusion models that may have practical implications for many aspects of financial markets.

Interpreting parameters in the logistic regression model with random effects

DEFF Research Database (Denmark)

Larsen, Klaus; Petersen, Jørgen Holm; Budtz-Jørgensen, Esben

2000-01-01

interpretation, interval odds ratio, logistic regression, median odds ratio, normally distributed random effects......interpretation, interval odds ratio, logistic regression, median odds ratio, normally distributed random effects...

Zero-inflated count models for longitudinal measurements with heterogeneous random effects.

Science.gov (United States)

Zhu, Huirong; Luo, Sheng; DeSantis, Stacia M

2017-08-01

Longitudinal zero-inflated count data arise frequently in substance use research when assessing the effects of behavioral and pharmacological interventions. Zero-inflated count models (e.g. zero-inflated Poisson or zero-inflated negative binomial) with random effects have been developed to analyze this type of data. In random effects zero-inflated count models, the random effects covariance matrix is typically assumed to be homogeneous (constant across subjects). However, in many situations this matrix may be heterogeneous (differ by measured covariates). In this paper, we extend zero-inflated count models to account for random effects heterogeneity by modeling their variance as a function of covariates. We show via simulation that ignoring intervention and covariate-specific heterogeneity can produce biased estimates of covariate and random effect estimates. Moreover, those biased estimates can be rectified by correctly modeling the random effects covariance structure. The methodological development is motivated by and applied to the Combined Pharmacotherapies and Behavioral Interventions for Alcohol Dependence (COMBINE) study, the largest clinical trial of alcohol dependence performed in United States with 1383 individuals.

Estimating overall exposure effects for the clustered and censored outcome using random effect Tobit regression models.

Science.gov (United States)

Wang, Wei; Griswold, Michael E

2016-11-30

The random effect Tobit model is a regression model that accommodates both left- and/or right-censoring and within-cluster dependence of the outcome variable. Regression coefficients of random effect Tobit models have conditional interpretations on a constructed latent dependent variable and do not provide inference of overall exposure effects on the original outcome scale. Marginalized random effects model (MREM) permits likelihood-based estimation of marginal mean parameters for the clustered data. For random effect Tobit models, we extend the MREM to marginalize over both the random effects and the normal space and boundary components of the censored response to estimate overall exposure effects at population level. We also extend the 'Average Predicted Value' method to estimate the model-predicted marginal means for each person under different exposure status in a designated reference group by integrating over the random effects and then use the calculated difference to assess the overall exposure effect. The maximum likelihood estimation is proposed utilizing a quasi-Newton optimization algorithm with Gauss-Hermite quadrature to approximate the integration of the random effects. We use these methods to carefully analyze two real datasets. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Assessing robustness of designs for random effects parameters for nonlinear mixed-effects models.

Science.gov (United States)

Duffull, Stephen B; Hooker, Andrew C

2017-12-01

Optimal designs for nonlinear models are dependent on the choice of parameter values. Various methods have been proposed to provide designs that are robust to uncertainty in the prior choice of parameter values. These methods are generally based on estimating the expectation of the determinant (or a transformation of the determinant) of the information matrix over the prior distribution of the parameter values. For high dimensional models this can be computationally challenging. For nonlinear mixed-effects models the question arises as to the importance of accounting for uncertainty in the prior value of the variances of the random effects parameters. In this work we explore the influence of the variance of the random effects parameters on the optimal design. We find that the method for approximating the expectation and variance of the likelihood is of potential importance for considering the influence of random effects. The most common approximation to the likelihood, based on a first-order Taylor series approximation, yields designs that are relatively insensitive to the prior value of the variance of the random effects parameters and under these conditions it appears to be sufficient to consider uncertainty on the fixed-effects parameters only.

Simulation of a directed random-walk model: the effect of pseudo-random-number correlations

OpenAIRE

Shchur, L. N.; Heringa, J. R.; Blöte, H. W. J.

1996-01-01

We investigate the mechanism that leads to systematic deviations in cluster Monte Carlo simulations when correlated pseudo-random numbers are used. We present a simple model, which enables an analysis of the effects due to correlations in several types of pseudo-random-number sequences. This model provides qualitative understanding of the bias mechanism in a class of cluster Monte Carlo algorithms.

Alpha-Band Activity Reveals Spontaneous Representations of Spatial Position in Visual Working Memory.

Science.gov (United States)

Foster, Joshua J; Bsales, Emma M; Jaffe, Russell J; Awh, Edward

2017-10-23

An emerging view suggests that spatial position is an integral component of working memory (WM), such that non-spatial features are bound to locations regardless of whether space is relevant [1, 2]. For instance, past work has shown that stimulus position is spontaneously remembered when non-spatial features are stored. Item recognition is enhanced when memoranda appear at the same location where they were encoded [3-5], and accessing non-spatial information elicits shifts of spatial attention to the original position of the stimulus [6, 7]. However, these findings do not establish that a persistent, active representation of stimulus position is maintained in WM because similar effects have also been documented following storage in long-term memory [8, 9]. Here we show that the spatial position of the memorandum is actively coded by persistent neural activity during a non-spatial WM task. We used a spatial encoding model in conjunction with electroencephalogram (EEG) measurements of oscillatory alpha-band (8-12 Hz) activity to track active representations of spatial position. The position of the stimulus varied trial to trial but was wholly irrelevant to the tasks. We nevertheless observed active neural representations of the original stimulus position that persisted throughout the retention interval. Further experiments established that these spatial representations are dependent on the volitional storage of non-spatial features rather than being a lingering effect of sensory energy or initial encoding demands. These findings provide strong evidence that online spatial representations are spontaneously maintained in WM-regardless of task relevance-during the storage of non-spatial features. Copyright © 2017 Elsevier Ltd. All rights reserved.

93-106, 2015 93 Multilevel random effect and marginal models

African Journals Online (AJOL)

Multilevel random effect and marginal models for longitudinal data ... and random effect models that take the correlation among measurements of the same subject ... comparing the level of redness, pain and irritability ... clinical trial evaluating the safety profile of a new .... likelihood-based methods to compare models and.

Random forests of interaction trees for estimating individualized treatment effects in randomized trials.

Science.gov (United States)

Su, Xiaogang; Peña, Annette T; Liu, Lei; Levine, Richard A

2018-04-29

Assessing heterogeneous treatment effects is a growing interest in advancing precision medicine. Individualized treatment effects (ITEs) play a critical role in such an endeavor. Concerning experimental data collected from randomized trials, we put forward a method, termed random forests of interaction trees (RFIT), for estimating ITE on the basis of interaction trees. To this end, we propose a smooth sigmoid surrogate method, as an alternative to greedy search, to speed up tree construction. The RFIT outperforms the "separate regression" approach in estimating ITE. Furthermore, standard errors for the estimated ITE via RFIT are obtained with the infinitesimal jackknife method. We assess and illustrate the use of RFIT via both simulation and the analysis of data from an acupuncture headache trial. Copyright © 2018 John Wiley & Sons, Ltd.

Spatial and visuospatial working memory tests predict performance in classic multiple-object tracking in young adults, but nonspatial measures of the executive do not.

Science.gov (United States)

Trick, Lana M; Mutreja, Rachna; Hunt, Kelly

2012-02-01

An individual-differences approach was used to investigate the roles of visuospatial working memory and the executive in multiple-object tracking. The Corsi Blocks and Visual Patterns Tests were used to assess visuospatial working memory. Two relatively nonspatial measures of the executive were used: operation span (OSPAN) and reading span (RSPAN). For purposes of comparison, the digit span test was also included (a measure not expected to correlate with tracking). The tests predicted substantial amounts of variance (R (2) = .33), and the visuospatial measures accounted for the majority (R (2) = .30), with each making a significant contribution. Although the executive measures correlated with each other, the RSPAN did not correlate with tracking. The correlation between OSPAN and tracking was similar in magnitude to that between digit span and tracking (p < .05 for both), and when regression was used to partial out shared variance between the two tests, the remaining variance predicted by the OSPAN was minimal (sr ( 2 ) = .029). When measures of spatial memory were included in the regression, the unique variance predicted by the OSPAN became negligible (sr ( 2 ) = .000004). This suggests that the executive, as measured by tests such as the OSPAN, plays little role in explaining individual differences in multiple-object tracking.

Small-world effect induced by weight randomization on regular networks

International Nuclear Information System (INIS)

Li, Menghui; Fan, Ying; Wang, Dahui; Li, Daqing; Wu, Jinshan; Di, Zengru

2007-01-01

The concept of edge weight provides additional depth for describing and adjusting the properties of networks. Redistribution of edge weight can effectively change the properties of networks even though the corresponding binary topology remains unchanged. Based on regular networks with initially homogeneous dissimilarity weights, random redistribution of edge weight can be enough to induce small world phenomena. The effects of random weight redistribution on both static properties and dynamical models of networks are investigated. The results reveal that randomization of weight can enhance the ability of synchronization of chaotic systems dramatically

The blocked-random effect in pictures and words.

Science.gov (United States)

Toglia, M P; Hinman, P J; Dayton, B S; Catalano, J F

1997-06-01

Picture and word recall was examined in conjunction with list organization. 60 subjects studied a list of 30 items, either words or their pictorial equivalents. The 30 words/pictures, members of five conceptual categories, each represented by six exemplars, were presented either blocked by category or in a random order. While pictures were recalled better than words and a standard blocked-random effect was observed, the interaction indicated that the recall advantage of a blocked presentation was restricted to the word lists. A similar pattern emerged for clustering. These findings are discussed in terms of limitations upon the pictorial superiority effect.

A dynamic random effects multinomial logit model of household car ownership

DEFF Research Database (Denmark)

Bue Bjørner, Thomas; Leth-Petersen, Søren

2007-01-01

Using a large household panel we estimate demand for car ownership by means of a dynamic multinomial model with correlated random effects. Results suggest that the persistence in car ownership observed in the data should be attributed to both true state dependence and to unobserved heterogeneity...... (random effects). It also appears that random effects related to single and multiple car ownership are correlated, suggesting that the IIA assumption employed in simple multinomial models of car ownership is invalid. Relatively small elasticities with respect to income and car costs are estimated...

Effect of random edge failure on the average path length

Energy Technology Data Exchange (ETDEWEB)

Guo Dongchao; Liang Mangui; Li Dandan; Jiang Zhongyuan, E-mail: mgliang58@gmail.com, E-mail: 08112070@bjtu.edu.cn [Institute of Information Science, Beijing Jiaotong University, 100044, Beijing (China)

2011-10-14

We study the effect of random removal of edges on the average path length (APL) in a large class of uncorrelated random networks in which vertices are characterized by hidden variables controlling the attachment of edges between pairs of vertices. A formula for approximating the APL of networks suffering random edge removal is derived first. Then, the formula is confirmed by simulations for classical ER (Erdoes and Renyi) random graphs, BA (Barabasi and Albert) networks, networks with exponential degree distributions as well as random networks with asymptotic power-law degree distributions with exponent {alpha} > 2. (paper)

Effects of changing the random number stride in Monte Carlo calculations

International Nuclear Information System (INIS)

Hendricks, J.S.

1991-01-01

This paper reports on a common practice in Monte Carlo radiation transport codes which is to start each random walk a specified number of steps up the random number sequence from the previous one. This is called the stride in the random number sequence between source particles. It is used for correlated sampling or to provide tree-structured random numbers. A new random number generator algorithm for the major Monte Carlo code MCNP has been written to allow adjustment of the random number stride. This random number generator is machine portable. The effects of varying the stride for several sample problems are examined

Application of Poisson random effect models for highway network screening.

Science.gov (United States)

Jiang, Ximiao; Abdel-Aty, Mohamed; Alamili, Samer

2014-02-01

In recent years, Bayesian random effect models that account for the temporal and spatial correlations of crash data became popular in traffic safety research. This study employs random effect Poisson Log-Normal models for crash risk hotspot identification. Both the temporal and spatial correlations of crash data were considered. Potential for Safety Improvement (PSI) were adopted as a measure of the crash risk. Using the fatal and injury crashes that occurred on urban 4-lane divided arterials from 2006 to 2009 in the Central Florida area, the random effect approaches were compared to the traditional Empirical Bayesian (EB) method and the conventional Bayesian Poisson Log-Normal model. A series of method examination tests were conducted to evaluate the performance of different approaches. These tests include the previously developed site consistence test, method consistence test, total rank difference test, and the modified total score test, as well as the newly proposed total safety performance measure difference test. Results show that the Bayesian Poisson model accounting for both temporal and spatial random effects (PTSRE) outperforms the model that with only temporal random effect, and both are superior to the conventional Poisson Log-Normal model (PLN) and the EB model in the fitting of crash data. Additionally, the method evaluation tests indicate that the PTSRE model is significantly superior to the PLN model and the EB model in consistently identifying hotspots during successive time periods. The results suggest that the PTSRE model is a superior alternative for road site crash risk hotspot identification. Copyright © 2013 Elsevier Ltd. All rights reserved.

Effects of psychological therapies in randomized trials and practice-based studies.

Science.gov (United States)

Barkham, Michael; Stiles, William B; Connell, Janice; Twigg, Elspeth; Leach, Chris; Lucock, Mike; Mellor-Clark, John; Bower, Peter; King, Michael; Shapiro, David A; Hardy, Gillian E; Greenberg, Leslie; Angus, Lynne

2008-11-01

Randomized trials of the effects of psychological therapies seek internal validity via homogeneous samples and standardized treatment protocols. In contrast, practice-based studies aim for clinical realism and external validity via heterogeneous samples of clients treated under routine practice conditions. We compared indices of treatment effects in these two types of studies. Using published transformation formulas, the Beck Depression Inventory (BDI) scores from five randomized trials of depression (N = 477 clients) were transformed into Clinical Outcomes in Routine Evaluation-Outcome Measure (CORE-OM) scores and compared with CORE-OM data collected in four practice-based studies (N = 4,196 clients). Conversely, the practice-based studies' CORE-OM scores were transformed into BDI scores and compared with randomized trial data. Randomized trials showed a modest advantage over practice-based studies in amount of pre-post improvement. This difference was compressed or exaggerated depending on the direction of the transformation but averaged about 12%. There was a similarly sized advantage to randomized trials in rates of reliable and clinically significant improvement (RCSI). The largest difference was yielded by comparisons of effect sizes which suggested an advantage more than twice as large, reflecting narrower pre-treatment distributions in the randomized trials. Outcomes of completed treatments for depression in randomized trials appeared to be modestly greater than those in routine care settings. The size of the difference may be distorted depending on the method for calculating degree of change. Transforming BDI scores into CORE-OM scores and vice versa may be a preferable alternative to effect sizes for comparisons of studies using these measures.

A single-level random-effects cross-lagged panel model for longitudinal mediation analysis.

Science.gov (United States)

Wu, Wei; Carroll, Ian A; Chen, Po-Yi

2017-12-06

Cross-lagged panel models (CLPMs) are widely used to test mediation with longitudinal panel data. One major limitation of the CLPMs is that the model effects are assumed to be fixed across individuals. This assumption is likely to be violated (i.e., the model effects are random across individuals) in practice. When this happens, the CLPMs can potentially yield biased parameter estimates and misleading statistical inferences. This article proposes a model named a random-effects cross-lagged panel model (RE-CLPM) to account for random effects in CLPMs. Simulation studies show that the RE-CLPM outperforms the CLPM in recovering the mean indirect and direct effects in a longitudinal mediation analysis when random effects exist in the population. The performance of the RE-CLPM is robust to a certain degree, even when the random effects are not normally distributed. In addition, the RE-CLPM does not produce harmful results when the model effects are in fact fixed in the population. Implications of the simulation studies and potential directions for future research are discussed.

Random effect selection in generalised linear models

DEFF Research Database (Denmark)

Denwood, Matt; Houe, Hans; Forkman, Björn

We analysed abattoir recordings of meat inspection codes with possible relevance to onfarm animal welfare in cattle. Random effects logistic regression models were used to describe individual-level data obtained from 461,406 cattle slaughtered in Denmark. Our results demonstrate that the largest...

Parallel Mitogenome Sequencing Alleviates Random Rooting Effect in Phylogeography.

Science.gov (United States)

Hirase, Shotaro; Takeshima, Hirohiko; Nishida, Mutsumi; Iwasaki, Wataru

2016-04-28

Reliably rooted phylogenetic trees play irreplaceable roles in clarifying diversification in the patterns of species and populations. However, such trees are often unavailable in phylogeographic studies, particularly when the focus is on rapidly expanded populations that exhibit star-like trees. A fundamental bottleneck is known as the random rooting effect, where a distant outgroup tends to root an unrooted tree "randomly." We investigated whether parallel mitochondrial genome (mitogenome) sequencing alleviates this effect in phylogeography using a case study on the Sea of Japan lineage of the intertidal goby Chaenogobius annularis Eighty-three C. annularis individuals were collected and their mitogenomes were determined by high-throughput and low-cost parallel sequencing. Phylogenetic analysis of these mitogenome sequences was conducted to root the Sea of Japan lineage, which has a star-like phylogeny and had not been reliably rooted. The topologies of the bootstrap trees were investigated to determine whether the use of mitogenomes alleviated the random rooting effect. The mitogenome data successfully rooted the Sea of Japan lineage by alleviating the effect, which hindered phylogenetic analysis that used specific gene sequences. The reliable rooting of the lineage led to the discovery of a novel, northern lineage that expanded during an interglacial period with high bootstrap support. Furthermore, the finding of this lineage suggested the existence of additional glacial refugia and provided a new recent calibration point that revised the divergence time estimation between the Sea of Japan and Pacific Ocean lineages. This study illustrates the effectiveness of parallel mitogenome sequencing for solving the random rooting problem in phylogeographic studies. © The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

A simulation-based goodness-of-fit test for random effects in generalized linear mixed models

DEFF Research Database (Denmark)

Waagepetersen, Rasmus

2006-01-01

The goodness-of-fit of the distribution of random effects in a generalized linear mixed model is assessed using a conditional simulation of the random effects conditional on the observations. Provided that the specified joint model for random effects and observations is correct, the marginal...... distribution of the simulated random effects coincides with the assumed random effects distribution. In practice, the specified model depends on some unknown parameter which is replaced by an estimate. We obtain a correction for this by deriving the asymptotic distribution of the empirical distribution...

A simulation-based goodness-of-fit test for random effects in generalized linear mixed models

DEFF Research Database (Denmark)

Waagepetersen, Rasmus Plenge

The goodness-of-fit of the distribution of random effects in a generalized linear mixed model is assessed using a conditional simulation of the random effects conditional on the observations. Provided that the specified joint model for random effects and observations is correct, the marginal...... distribution of the simulated random effects coincides with the assumed random effects distribution. In practice the specified model depends on some unknown parameter which is replaced by an estimate. We obtain a correction for this by deriving the asymptotic distribution of the empirical distribution function...

Effects of randomness on chaos and order of coupled logistic maps

International Nuclear Information System (INIS)

Savi, Marcelo A.

2007-01-01

Natural systems are essentially nonlinear being neither completely ordered nor completely random. These nonlinearities are responsible for a great variety of possibilities that includes chaos. On this basis, the effect of randomness on chaos and order of nonlinear dynamical systems is an important feature to be understood. This Letter considers randomness as fluctuations and uncertainties due to noise and investigates its influence in the nonlinear dynamical behavior of coupled logistic maps. The noise effect is included by adding random variations either to parameters or to state variables. Besides, the coupling uncertainty is investigated by assuming tinny values for the connection parameters, representing the idea that all Nature is, in some sense, weakly connected. Results from numerical simulations show situations where noise alters the system nonlinear dynamics

Application of random effects to the study of resource selection by animals.

Science.gov (United States)

Gillies, Cameron S; Hebblewhite, Mark; Nielsen, Scott E; Krawchuk, Meg A; Aldridge, Cameron L; Frair, Jacqueline L; Saher, D Joanne; Stevens, Cameron E; Jerde, Christopher L

2006-07-01

1. Resource selection estimated by logistic regression is used increasingly in studies to identify critical resources for animal populations and to predict species occurrence. 2. Most frequently, individual animals are monitored and pooled to estimate population-level effects without regard to group or individual-level variation. Pooling assumes that both observations and their errors are independent, and resource selection is constant given individual variation in resource availability. 3. Although researchers have identified ways to minimize autocorrelation, variation between individuals caused by differences in selection or available resources, including functional responses in resource selection, have not been well addressed. 4. Here we review random-effects models and their application to resource selection modelling to overcome these common limitations. We present a simple case study of an analysis of resource selection by grizzly bears in the foothills of the Canadian Rocky Mountains with and without random effects. 5. Both categorical and continuous variables in the grizzly bear model differed in interpretation, both in statistical significance and coefficient sign, depending on how a random effect was included. We used a simulation approach to clarify the application of random effects under three common situations for telemetry studies: (a) discrepancies in sample sizes among individuals; (b) differences among individuals in selection where availability is constant; and (c) differences in availability with and without a functional response in resource selection. 6. We found that random intercepts accounted for unbalanced sample designs, and models with random intercepts and coefficients improved model fit given the variation in selection among individuals and functional responses in selection. Our empirical example and simulations demonstrate how including random effects in resource selection models can aid interpretation and address difficult assumptions

Neighborhood Effects in a Behavioral Randomized Controlled Trial

OpenAIRE

Pruitt, Sandi L.; Leonard, Tammy; Murdoch, James; Hughes, Amy; McQueen, Amy; Gupta, Samir

2014-01-01

Randomized controlled trials (RCTs) of interventions intended to modify health behaviors may be influenced by neighborhood effects which can impede unbiased estimation of intervention effects. Examining a RCT designed to increase colorectal cancer (CRC) screening (N=5,628), we found statistically significant neighborhood effects: average CRC test use among neighboring study participants was significantly and positively associated with individual patient’s CRC test use. This potentially import...

Effective Perron-Frobenius eigenvalue for a correlated random map

Science.gov (United States)

Pool, Roman R.; Cáceres, Manuel O.

2010-09-01

We investigate the evolution of random positive linear maps with various type of disorder by analytic perturbation and direct simulation. Our theoretical result indicates that the statistics of a random linear map can be successfully described for long time by the mean-value vector state. The growth rate can be characterized by an effective Perron-Frobenius eigenvalue that strongly depends on the type of correlation between the elements of the projection matrix. We apply this approach to an age-structured population dynamics model. We show that the asymptotic mean-value vector state characterizes the population growth rate when the age-structured model has random vital parameters. In this case our approach reveals the nontrivial dependence of the effective growth rate with cross correlations. The problem was reduced to the calculation of the smallest positive root of a secular polynomial, which can be obtained by perturbations in terms of Green’s function diagrammatic technique built with noncommutative cumulants for arbitrary n -point correlations.

Application of spatial and non-spatial data analysis in determination of the factors that impact municipal solid waste generation rates in Turkey

International Nuclear Information System (INIS)

Keser, Saniye; Duzgun, Sebnem; Aksoy, Aysegul

2012-01-01

Highlights: ► Spatial autocorrelation exists in municipal solid waste generation rates for different provinces in Turkey. ► Traditional non-spatial regression models may not provide sufficient information for better solid waste management. ► Unemployment rate is a global variable that significantly impacts the waste generation rates in Turkey. ► Significances of global parameters may diminish at local scale for some provinces. ► GWR model can be used to create clusters of cities for solid waste management. - Abstract: In studies focusing on the factors that impact solid waste generation habits and rates, the potential spatial dependency in solid waste generation data is not considered in relating the waste generation rates to its determinants. In this study, spatial dependency is taken into account in determination of the significant socio-economic and climatic factors that may be of importance for the municipal solid waste (MSW) generation rates in different provinces of Turkey. Simultaneous spatial autoregression (SAR) and geographically weighted regression (GWR) models are used for the spatial data analyses. Similar to ordinary least squares regression (OLSR), regression coefficients are global in SAR model. In other words, the effect of a given independent variable on a dependent variable is valid for the whole country. Unlike OLSR or SAR, GWR reveals the local impact of a given factor (or independent variable) on the waste generation rates of different provinces. Results show that provinces within closer neighborhoods have similar MSW generation rates. On the other hand, this spatial autocorrelation is not very high for the exploratory variables considered in the study. OLSR and SAR models have similar regression coefficients. GWR is useful to indicate the local determinants of MSW generation rates. GWR model can be utilized to plan waste management activities at local scale including waste minimization, collection, treatment, and disposal. At global

Analog model for quantum gravity effects: phonons in random fluids.

Science.gov (United States)

Krein, G; Menezes, G; Svaiter, N F

2010-09-24

We describe an analog model for quantum gravity effects in condensed matter physics. The situation discussed is that of phonons propagating in a fluid with a random velocity wave equation. We consider that there are random fluctuations in the reciprocal of the bulk modulus of the system and study free phonons in the presence of Gaussian colored noise with zero mean. We show that, in this model, after performing the random averages over the noise function a free conventional scalar quantum field theory describing free phonons becomes a self-interacting model.

Predicting longitudinal trajectories of health probabilities with random-effects multinomial logit regression.

Science.gov (United States)

Liu, Xian; Engel, Charles C

2012-12-20

Researchers often encounter longitudinal health data characterized with three or more ordinal or nominal categories. Random-effects multinomial logit models are generally applied to account for potential lack of independence inherent in such clustered data. When parameter estimates are used to describe longitudinal processes, however, random effects, both between and within individuals, need to be retransformed for correctly predicting outcome probabilities. This study attempts to go beyond existing work by developing a retransformation method that derives longitudinal growth trajectories of unbiased health probabilities. We estimated variances of the predicted probabilities by using the delta method. Additionally, we transformed the covariates' regression coefficients on the multinomial logit function, not substantively meaningful, to the conditional effects on the predicted probabilities. The empirical illustration uses the longitudinal data from the Asset and Health Dynamics among the Oldest Old. Our analysis compared three sets of the predicted probabilities of three health states at six time points, obtained from, respectively, the retransformation method, the best linear unbiased prediction, and the fixed-effects approach. The results demonstrate that neglect of retransforming random errors in the random-effects multinomial logit model results in severely biased longitudinal trajectories of health probabilities as well as overestimated effects of covariates on the probabilities. Copyright © 2012 John Wiley & Sons, Ltd.

Effects of Topological Randomness on Cooperation in a Deterministic Prisoner's Dilemma Game

International Nuclear Information System (INIS)

Zhang Mei; Yang Junzhong

2011-01-01

In this work, we consider an evolutionary prisoner's dilemma game on a homogeneous random network with the richest-following strategy adoption rule. By constructing homogeneous random networks from a regular ring graph, we investigate the effects of topological randomness on cooperation. In contrast to the ordinary view that the presence of small amount of shortcuts in ring graphs favors cooperation, we find the cooperation inhibition by weak topological randomness. The explanations on the observations are presented. (general)

Random Process Theory Approach to Geometric Heterogeneous Surfaces: Effective Fluid-Solid Interaction

Science.gov (United States)

Khlyupin, Aleksey; Aslyamov, Timur

2017-06-01

Realistic fluid-solid interaction potentials are essential in description of confined fluids especially in the case of geometric heterogeneous surfaces. Correlated random field is considered as a model of random surface with high geometric roughness. We provide the general theory of effective coarse-grained fluid-solid potential by proper averaging of the free energy of fluid molecules which interact with the solid media. This procedure is largely based on the theory of random processes. We apply first passage time probability problem and assume the local Markov properties of random surfaces. General expression of effective fluid-solid potential is obtained. In the case of small surface irregularities analytical approximation for effective potential is proposed. Both amorphous materials with large surface roughness and crystalline solids with several types of fcc lattices are considered. It is shown that the wider the lattice spacing in terms of molecular diameter of the fluid, the more obtained potentials differ from classical ones. A comparison with published Monte-Carlo simulations was discussed. The work provides a promising approach to explore how the random geometric heterogeneity affects on thermodynamic properties of the fluids.

The effects of heavy particle irradiation on exploration and response to environmental change

Science.gov (United States)

Casadesus, G.; Shukitt-Hale, B.; Cantuti-Castelvetri, I.; Rabin, B.; Joseph, J.

Free radicals produced by exposure to heavy particles have been found to produce motor and behavioral toxicity effects in rats similar to those found during aging. The present research was designed to investigate the effects of exposure to 56Fe particles on the ability to detect novel arrangements in a given environment of male Sprague-Dawley rats. Using a test of spatial memory previously demonstrated to be sensitive to aging, open-field activity and reaction to spatial and non-spatial changes were measured in a group that received a dose of 1.5 Gy (n=10) of 56Fe heavy particle radiation or in non- radiated controls. Animals irradiated with 1.5 Gy of56Fe particles exhibited some age-like effects in animals tested, even though they were for the most part, subtle. Animals took longer to enter, visited less and spent significantly less time in the middle and the center portions of the open-field independently of total frequency and duration of activity of both groups. Likewise, irradiated subjects reacted significantly more to novel objects placed in the open-field than did controls. However, irradiated subjects did not vary from controls in their exploration patterns when objects in the open-field were spatially rearranged. Thus, irradiation with a dose of 1.5 Gy of 56Fe high-energy particle radiation elicited age-like effects in general open-field exploratory behavior, but did not elicit age- like effects during the spatial and non-spatial rearrangement tasks. Supported by N.A.S.A. Grant NAG9-1190.

Quantum random number generator based on quantum tunneling effect

OpenAIRE

Zhou, Haihan; Li, Junlin; Pan, Dong; Zhang, Weixing; Long, Guilu

2017-01-01

In this paper, we proposed an experimental implementation of quantum random number generator(QRNG) with inherent randomness of quantum tunneling effect of electrons. We exploited InGaAs/InP diodes, whose valance band and conduction band shared a quasi-constant energy barrier. We applied a bias voltage on the InGaAs/InP avalanche diode, which made the diode works under Geiger mode, and triggered the tunneling events with a periodic pulse. Finally, after data collection and post-processing, our...

Network meta-analysis of disconnected networks: How dangerous are random baseline treatment effects?

Science.gov (United States)

Béliveau, Audrey; Goring, Sarah; Platt, Robert W; Gustafson, Paul

2017-12-01

In network meta-analysis, the use of fixed baseline treatment effects (a priori independent) in a contrast-based approach is regularly preferred to the use of random baseline treatment effects (a priori dependent). That is because, often, there is not a need to model baseline treatment effects, which carry the risk of model misspecification. However, in disconnected networks, fixed baseline treatment effects do not work (unless extra assumptions are made), as there is not enough information in the data to update the prior distribution on the contrasts between disconnected treatments. In this paper, we investigate to what extent the use of random baseline treatment effects is dangerous in disconnected networks. We take 2 publicly available datasets of connected networks and disconnect them in multiple ways. We then compare the results of treatment comparisons obtained from a Bayesian contrast-based analysis of each disconnected network using random normally distributed and exchangeable baseline treatment effects to those obtained from a Bayesian contrast-based analysis of their initial connected network using fixed baseline treatment effects. For the 2 datasets considered, we found that the use of random baseline treatment effects in disconnected networks was appropriate. Because those datasets were not cherry-picked, there should be other disconnected networks that would benefit from being analyzed using random baseline treatment effects. However, there is also a risk for the normality and exchangeability assumption to be inappropriate in other datasets even though we have not observed this situation in our case study. We provide code, so other datasets can be investigated. Copyright © 2017 John Wiley & Sons, Ltd.

Local lattice relaxations in random metallic alloys: Effective tetrahedron model and supercell approach

DEFF Research Database (Denmark)

Ruban, Andrei; Simak, S.I.; Shallcross, S.

2003-01-01

We present a simple effective tetrahedron model for local lattice relaxation effects in random metallic alloys on simple primitive lattices. A comparison with direct ab initio calculations for supercells representing random Ni0.50Pt0.50 and Cu0.25Au0.75 alloys as well as the dilute limit of Au-ri......-rich CuAu alloys shows that the model yields a quantitatively accurate description of the relaxtion energies in these systems. Finally, we discuss the bond length distribution in random alloys....

The effect of atomoxetine on random and directed exploration in humans.

Science.gov (United States)

Warren, Christopher M; Wilson, Robert C; van der Wee, Nic J; Giltay, Eric J; van Noorden, Martijn S; Cohen, Jonathan D; Nieuwenhuis, Sander

2017-01-01

The adaptive regulation of the trade-off between pursuing a known reward (exploitation) and sampling lesser-known options in search of something better (exploration) is critical for optimal performance. Theory and recent empirical work suggest that humans use at least two strategies for solving this dilemma: a directed strategy in which choices are explicitly biased toward information seeking, and a random strategy in which decision noise leads to exploration by chance. Here we examined the hypothesis that random exploration is governed by the neuromodulatory locus coeruleus-norepinephrine system. We administered atomoxetine, a norepinephrine transporter blocker that increases extracellular levels of norepinephrine throughout the cortex, to 22 healthy human participants in a double-blind crossover design. We examined the effect of treatment on performance in a gambling task designed to produce distinct measures of directed exploration and random exploration. In line with our hypothesis we found an effect of atomoxetine on random, but not directed exploration. However, contrary to expectation, atomoxetine reduced rather than increased random exploration. We offer three potential explanations of our findings, involving the non-linear relationship between tonic NE and cognitive performance, the interaction of atomoxetine with other neuromodulators, and the possibility that atomoxetine affected phasic norepinephrine activity more so than tonic norepinephrine activity.

Effects of unstratified and centre-stratified randomization in multi-centre clinical trials.

Science.gov (United States)

Anisimov, Vladimir V

2011-01-01

This paper deals with the analysis of randomization effects in multi-centre clinical trials. The two randomization schemes most often used in clinical trials are considered: unstratified and centre-stratified block-permuted randomization. The prediction of the number of patients randomized to different treatment arms in different regions during the recruitment period accounting for the stochastic nature of the recruitment and effects of multiple centres is investigated. A new analytic approach using a Poisson-gamma patient recruitment model (patients arrive at different centres according to Poisson processes with rates sampled from a gamma distributed population) and its further extensions is proposed. Closed-form expressions for corresponding distributions of the predicted number of the patients randomized in different regions are derived. In the case of two treatments, the properties of the total imbalance in the number of patients on treatment arms caused by using centre-stratified randomization are investigated and for a large number of centres a normal approximation of imbalance is proved. The impact of imbalance on the power of the study is considered. It is shown that the loss of statistical power is practically negligible and can be compensated by a minor increase in sample size. The influence of patient dropout is also investigated. The impact of randomization on predicted drug supply overage is discussed. Copyright © 2010 John Wiley & Sons, Ltd.

An effective Hamiltonian approach to quantum random walk

Indian Academy of Sciences (India)

2017-02-09

Feb 9, 2017 ... Abstract. In this article we present an effective Hamiltonian approach for discrete time quantum random walk. A form of the Hamiltonian for one-dimensional quantum walk has been prescribed, utilizing the fact that Hamil- tonians are generators of time translations. Then an attempt has been made to ...

Research of the Space Clustering Method for the Airport Noise Data Minings

Directory of Open Access Journals (Sweden)

Jiwen Xie

2014-03-01

Full Text Available Mining the distribution pattern and evolution of the airport noise from the airport noise data and the geographic information of the monitoring points is of great significance for the scientific and rational governance of airport noise pollution problem. However, most of the traditional clustering methods are based on the closeness of space location or the similarity of non-spatial features, which split the duality of space elements, resulting in that the clustering result has difficult in satisfying both the closeness of space location and the similarity of non-spatial features. This paper, therefore, proposes a spatial clustering algorithm based on dual-distance. This algorithm uses a distance function as the similarity measure function in which spatial features and non-spatial features are combined. The experimental results show that the proposed algorithm can discover the noise distribution pattern around the airport effectively.

Nonparametric Estimation of Distributions in Random Effects Models

KAUST Repository

Hart, Jeffrey D.

2011-01-01

We propose using minimum distance to obtain nonparametric estimates of the distributions of components in random effects models. A main setting considered is equivalent to having a large number of small datasets whose locations, and perhaps scales, vary randomly, but which otherwise have a common distribution. Interest focuses on estimating the distribution that is common to all datasets, knowledge of which is crucial in multiple testing problems where a location/scale invariant test is applied to every small dataset. A detailed algorithm for computing minimum distance estimates is proposed, and the usefulness of our methodology is illustrated by a simulation study and an analysis of microarray data. Supplemental materials for the article, including R-code and a dataset, are available online. © 2011 American Statistical Association.

Effective temperature in driven vortex lattices with random pinning

International Nuclear Information System (INIS)

Kolton, Alejandro B.; Dominguez, Daniel; Exartier, Raphael; Cugliandolo, Leticia F.; Groenbech-Jensen, N.

2003-09-01

We study numerically correlation and response functions in non-equilibrium driven vortex lattices with random pinning. From a generalized fluctuation-dissipation relation we calculate an effective transverse temperature in the fluid moving phase. We find that the effective temperature decreases with increasing driving force and becomes equal to the equilibrium melting temperature when the dynamic transverse freezing occurs. We also discuss how the effective temperature can be measured experimentally from a generalized Kubo formula. (author)

Disentangling the effects of alternation rate and maximum run length on judgments of randomness

Directory of Open Access Journals (Sweden)

Sabine G. Scholl

2011-08-01

Full Text Available Binary sequences are characterized by various features. Two of these characteristics---alternation rate and run length---have repeatedly been shown to influence judgments of randomness. The two characteristics, however, have usually been investigated separately, without controlling for the other feature. Because the two features are correlated but not identical, it seems critical to analyze their unique impact, as well as their interaction, so as to understand more clearly what influences judgments of randomness. To this end, two experiments on the perception of binary sequences orthogonally manipulated alternation rate and maximum run length (i.e., length of the longest run within the sequence. Results show that alternation rate consistently exerts a unique effect on judgments of randomness, but that the effect of alternation rate is contingent on the length of the longest run within the sequence. The effect of maximum run length was found to be small and less consistent. Together, these findings extend prior randomness research by integrating literature from the realms of perception, categorization, and prediction, as well as by showing the unique and joint effects of alternation rate and maximum run length on judgments of randomness.

Behavioral and Brain Measures of Phasic Alerting Effects on Visual Attention

DEFF Research Database (Denmark)

Wiegand, Iris Michaela; Petersen, Anders; Finke, Kathrin

2017-01-01

In the present study, we investigated effects of phasic alerting on visual attention in a partial report task, in which half of the displays were preceded by an auditory warning cue. Based on the computational Theory of Visual Attention (TVA), we estimated parameters of spatial and non......-spatial aspects of visual attention and measured event-related lateralizations (ERLs) over visual processing areas. We found that the TVA parameter sensory effectiveness a, which is thought to reflect visual processing capacity, significantly increased with phasic alerting. By contrast, the distribution of visual....... These results suggest that phasic alerting facilitates visual processing in a general, unselective manner and that this effect originates in early stages of visual information processing....

Correlation effects in a discrete quantum random walk

International Nuclear Information System (INIS)

Stang, J B; Rezakhani, A T; Sanders, B C

2009-01-01

We introduce memory-dependent discrete-time quantum random walk models by adding uncorrelated memory terms and also by modifying the Hamiltonian of the walker to include couplings with memory-keeping agents. We next study numerically the correlation effects in these models. We also propose a correlation exponent as a relevant and promising tool for investigation of correlation or memory (hence non-Markovian) effects. Our analysis can easily be applied to more realistic models in which different regimes may emerge because of competition between different underlying physical mechanisms

Neighborhood effects in a behavioral randomized controlled trial.

Science.gov (United States)

Pruitt, Sandi L; Leonard, Tammy; Murdoch, James; Hughes, Amy; McQueen, Amy; Gupta, Samir

2014-11-01

Randomized controlled trials (RCTs) of interventions intended to modify health behaviors may be influenced by neighborhood effects which can impede unbiased estimation of intervention effects. Examining a RCT designed to increase colorectal cancer (CRC) screening (N=5628), we found statistically significant neighborhood effects: average CRC test use among neighboring study participants was significantly and positively associated with individual patient's CRC test use. This potentially important spatially-varying covariate has not previously been considered in a RCT. Our results suggest that future RCTs of health behavior interventions should assess potential social interactions between participants, which may cause intervention arm contamination and may bias effect size estimation. Copyright © 2014 Elsevier Ltd. All rights reserved.

Examples of mixed-effects modeling with crossed random effects and with binomial data

NARCIS (Netherlands)

Quené, H.; van den Bergh, H.

2008-01-01

Psycholinguistic data are often analyzed with repeated-measures analyses of variance (ANOVA), but this paper argues that mixed-effects (multilevel) models provide a better alternative method. First, models are discussed in which the two random factors of participants and items are crossed, and not

Repairable system analysis in presence of covariates and random effects

International Nuclear Information System (INIS)

Giorgio, M.; Guida, M.; Pulcini, G.

2014-01-01

This paper aims to model the failure pattern of repairable systems in presence of explained and unexplained heterogeneity. The failure pattern of each system is described by a Power Law Process. Part of the heterogeneity among the patterns is explained through the use of a covariate, and the residual unexplained heterogeneity (random effects) is modeled via a joint probability distribution on the PLP parameters. The proposed approach is applied to a real set of failure time data of powertrain systems mounted on 33 buses employed in urban and suburban routes. Moreover, the joint probability distribution on the PLP parameters estimated from the data is used as an informative prior to make Bayesian inference on the future failure process of a generic system belonging to the same population and employed in an urban or suburban route under randomly chosen working conditions. - Highlights: • We describe the failure process of buses powertrain system subject to heterogeneity. • Heterogeneity due to different service types is explained by a covariate. • Random effect is modeled through a joint pdf on failure process parameters. • The powertrain reliability under new future operating conditions is estimated

Standardized Effect Size Measures for Mediation Analysis in Cluster-Randomized Trials

Science.gov (United States)

Stapleton, Laura M.; Pituch, Keenan A.; Dion, Eric

2015-01-01

This article presents 3 standardized effect size measures to use when sharing results of an analysis of mediation of treatment effects for cluster-randomized trials. The authors discuss 3 examples of mediation analysis (upper-level mediation, cross-level mediation, and cross-level mediation with a contextual effect) with demonstration of the…

Estimating required information size by quantifying diversity in random-effects model meta-analyses

DEFF Research Database (Denmark)

Wetterslev, Jørn; Thorlund, Kristian; Brok, Jesper

2009-01-01

an intervention effect suggested by trials with low-risk of bias. METHODS: Information size calculations need to consider the total model variance in a meta-analysis to control type I and type II errors. Here, we derive an adjusting factor for the required information size under any random-effects model meta......-analysis. RESULTS: We devise a measure of diversity (D2) in a meta-analysis, which is the relative variance reduction when the meta-analysis model is changed from a random-effects into a fixed-effect model. D2 is the percentage that the between-trial variability constitutes of the sum of the between...... and interpreted using several simulations and clinical examples. In addition we show mathematically that diversity is equal to or greater than inconsistency, that is D2 >or= I2, for all meta-analyses. CONCLUSION: We conclude that D2 seems a better alternative than I2 to consider model variation in any random...

A spatial error model with continuous random effects and an application to growth convergence

Science.gov (United States)

Laurini, Márcio Poletti

2017-10-01

We propose a spatial error model with continuous random effects based on Matérn covariance functions and apply this model for the analysis of income convergence processes (β -convergence). The use of a model with continuous random effects permits a clearer visualization and interpretation of the spatial dependency patterns, avoids the problems of defining neighborhoods in spatial econometrics models, and allows projecting the spatial effects for every possible location in the continuous space, circumventing the existing aggregations in discrete lattice representations. We apply this model approach to analyze the economic growth of Brazilian municipalities between 1991 and 2010 using unconditional and conditional formulations and a spatiotemporal model of convergence. The results indicate that the estimated spatial random effects are consistent with the existence of income convergence clubs for Brazilian municipalities in this period.

Random effects model for the reliability management of modules of a fighter aircraft

Energy Technology Data Exchange (ETDEWEB)

Sohn, So Young [Department of Computer Science and Industrial Systems Engineering, Yonsei University, Shinchondong 134, Seoul 120-749 (Korea, Republic of)]. E-mail: sohns@yonsei.ac.kr; Yoon, Kyung Bok [Department of Computer Science and Industrial Systems Engineering, Yonsei University, Shinchondong 134, Seoul 120-749 (Korea, Republic of)]. E-mail: ykb@yonsei.ac.kr; Chang, In Sang [Department of Computer Science and Industrial Systems Engineering, Yonsei University, Shinchondong 134, Seoul 120-749 (Korea, Republic of)]. E-mail: isjang@yonsei.ac.kr

2006-04-15

The operational availability of fighter aircrafts plays an important role in the national defense. Low operational availability of fighter aircrafts can cause many problems and ROKA (Republic of Korea Airforce) needs proper strategies to improve the current practice of reliability management by accurately forecasting both MTBF (mean time between failure) and MTTR (mean time to repair). In this paper, we develop a random effects model to forecast both MTBF and MTTR of installed modules of fighter aircrafts based on their characteristics and operational conditions. Advantage of using such a random effects model is the ability of accommodating not only the individual characteristics of each module and operational conditions but also the uncertainty caused by random error that cannot be explained by them. Our study is expected to contribute to ROKA in improving operational availability of fighter aircrafts and establishing effective logistics management.

The reverse effects of random perturbation on discrete systems for single and multiple population models

International Nuclear Information System (INIS)

Kang, Li; Tang, Sanyi

2016-01-01

Highlights: • The discrete single species and multiple species models with random perturbation are proposed. • The complex dynamics and interesting bifurcation behavior have been investigated. • The reverse effects of random perturbation on discrete systems have been discussed and revealed. • The main results can be applied for pest control and resources management. - Abstract: The natural species are likely to present several interesting and complex phenomena under random perturbations, which have been confirmed by simple mathematical models. The important questions are: how the random perturbations influence the dynamics of the discrete population models with multiple steady states or multiple species interactions? and is there any different effects for single species and multiple species models with random perturbation? To address those interesting questions, we have proposed the discrete single species model with two stable equilibria and the host-parasitoid model with Holling type functional response functions to address how the random perturbation affects the dynamics. The main results indicate that the random perturbation does not change the number of blurred orbits of the single species model with two stable steady states compared with results for the classical Ricker model with same random perturbation, but it can strength the stability. However, extensive numerical investigations depict that the random perturbation does not influence the complexities of the host-parasitoid models compared with the results for the models without perturbation, while it does increase the period of periodic orbits doubly. All those confirm that the random perturbation has a reverse effect on the dynamics of the discrete single and multiple population models, which could be applied in reality including pest control and resources management.

Effects of random noise in a dynamical model of love

Energy Technology Data Exchange (ETDEWEB)

Xu Yong, E-mail: hsux3@nwpu.edu.cn [Department of Applied Mathematics, Northwestern Polytechnical University, Xi' an 710072 (China); Gu Rencai; Zhang Huiqing [Department of Applied Mathematics, Northwestern Polytechnical University, Xi' an 710072 (China)

2011-07-15

Highlights: > We model the complexity and unpredictability of psychology as Gaussian white noise. > The stochastic system of love is considered including bifurcation and chaos. > We show that noise can both suppress and induce chaos in dynamical models of love. - Abstract: This paper aims to investigate the stochastic model of love and the effects of random noise. We first revisit the deterministic model of love and some basic properties are presented such as: symmetry, dissipation, fixed points (equilibrium), chaotic behaviors and chaotic attractors. Then we construct a stochastic love-triangle model with parametric random excitation due to the complexity and unpredictability of the psychological system, where the randomness is modeled as the standard Gaussian noise. Stochastic dynamics under different three cases of 'Romeo's romantic style', are examined and two kinds of bifurcations versus the noise intensity parameter are observed by the criteria of changes of top Lyapunov exponent and shape of stationary probability density function (PDF) respectively. The phase portraits and time history are carried out to verify the proposed results, and the good agreement can be found. And also the dual roles of the random noise, namely suppressing and inducing chaos are revealed.

Effects of random noise in a dynamical model of love

International Nuclear Information System (INIS)

Xu Yong; Gu Rencai; Zhang Huiqing

2011-01-01

Highlights: → We model the complexity and unpredictability of psychology as Gaussian white noise. → The stochastic system of love is considered including bifurcation and chaos. → We show that noise can both suppress and induce chaos in dynamical models of love. - Abstract: This paper aims to investigate the stochastic model of love and the effects of random noise. We first revisit the deterministic model of love and some basic properties are presented such as: symmetry, dissipation, fixed points (equilibrium), chaotic behaviors and chaotic attractors. Then we construct a stochastic love-triangle model with parametric random excitation due to the complexity and unpredictability of the psychological system, where the randomness is modeled as the standard Gaussian noise. Stochastic dynamics under different three cases of 'Romeo's romantic style', are examined and two kinds of bifurcations versus the noise intensity parameter are observed by the criteria of changes of top Lyapunov exponent and shape of stationary probability density function (PDF) respectively. The phase portraits and time history are carried out to verify the proposed results, and the good agreement can be found. And also the dual roles of the random noise, namely suppressing and inducing chaos are revealed.

The effectiveness of foot reflexology in inducing ovulation: a sham-controlled randomized trial.

Science.gov (United States)

Holt, Jane; Lord, Jonathan; Acharya, Umesh; White, Adrian; O'Neill, Nyree; Shaw, Steve; Barton, Andy

2009-06-01

To determine whether foot reflexology, a complementary therapy, has an effect greater than sham reflexology on induction of ovulation. Sham-controlled randomized trial with patients and statistician blinded. Infertility clinic in Plymouth, United Kingdom. Forty-eight women attending the clinic with anovulation. Women were randomized to receive eight sessions of either genuine foot reflexology or sham reflexology with gentle massage over 10 weeks. The primary outcome was ovulation detected by serum progesterone level of >30 nmol/L during the study period. Twenty-six patients were randomized to genuine reflexology and 22 to sham (one randomized patient was withdrawn). Patients remained blinded throughout the trial. The rate of ovulation during true reflexology was 11 out of 26 (42%), and during sham reflexology it was 10 out of 22 (46%). Pregnancy rates were 4 out of 26 in the true group and 2 out of 22 in the control group. Because of recruitment difficulties, the required sample size of 104 women was not achieved. Patient blinding of reflexology studies is feasible. Although this study was too small to reach a definitive conclusion on the specific effect of foot reflexology, the results suggest that any effect on ovulation would not be clinically relevant. Sham reflexology may have a beneficial general effect, which this study was not designed to detect.

Pattern or process? Evaluating the peninsula effect as a determinant of species richness in coastal dune forests.

Directory of Open Access Journals (Sweden)

Pieter I Olivier

Full Text Available The peninsula effect predicts that the number of species should decline from the base of a peninsula to the tip. However, evidence for the peninsula effect is ambiguous, as different analytical methods, study taxa, and variations in local habitat or regional climatic conditions influence conclusions on its presence. We address this uncertainty by using two analytical methods to investigate the peninsula effect in three taxa that occupy different trophic levels: trees, millipedes, and birds. We surveyed 81 tree quadrants, 102 millipede transects, and 152 bird points within 150 km of coastal dune forest that resemble a habitat peninsula along the northeast coast of South Africa. We then used spatial (trend surface analyses and non-spatial regressions (generalized linear mixed models to test for the presence of the peninsula effect in each of the three taxa. We also used linear mixed models to test if climate (temperature and precipitation and/or local habitat conditions (water availability associated with topography and landscape structural variables could explain gradients in species richness. Non-spatial models suggest that the peninsula effect was present in all three taxa. However, spatial models indicated that only bird species richness declined from the peninsula base to the peninsula tip. Millipede species richness increased near the centre of the peninsula, while tree species richness increased near the tip. Local habitat conditions explained species richness patterns of birds and trees, but not of millipedes, regardless of model type. Our study highlights the idiosyncrasies associated with the peninsula effect-conclusions on the presence of the peninsula effect depend on the analytical methods used and the taxon studied. The peninsula effect might therefore be better suited to describe a species richness pattern where the number of species decline from a broader habitat base to a narrow tip, rather than a process that drives species

Early handling effect on female rat spatial and non-spatial learning and memory.

Science.gov (United States)

Plescia, Fulvio; Marino, Rosa A M; Navarra, Michele; Gambino, Giuditta; Brancato, Anna; Sardo, Pierangelo; Cannizzaro, Carla

2014-03-01

This study aims at providing an insight into early handling procedures on learning and memory performance in adult female rats. Early handling procedures were started on post-natal day 2 until 21, and consisted in 15 min, daily separations of the dams from their litters. Assessment of declarative memory was carried out in the novel-object recognition task; spatial learning, reference- and working memory were evaluated in the Morris water maze (MWM). Our results indicate that early handling induced an enhancement in: (1) declarative memory, in the object recognition task, both at 1h and 24h intervals; (2) reference memory in the probe test and working memory and behavioral flexibility in the "single-trial and four-trial place learning paradigm" of the MWM. Short-term separation by increasing maternal care causes a dampening in HPA axis response in the pups. A modulated activation of the stress response may help to protect brain structures, involved in cognitive function. In conclusion, this study shows the long-term effects of a brief maternal separation in enhancing object recognition-, spatial reference- and working memory in female rats, remarking the impact of early environmental experiences and the consequent maternal care on the behavioral adaptive mechanisms in adulthood. Copyright © 2013 Elsevier B.V. All rights reserved.

Behavioral effects of neurofeedback in adolescents with ADHD: a randomized controlled trial.

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Bink, Marleen; van Nieuwenhuizen, Chijs; Popma, Arne; Bongers, Ilja L; van Boxtel, Geert J M

2015-09-01

Neurofeedback has been proposed as a potentially effective intervention for reducing Attention Deficit Hyperactivity Disorder (ADHD) symptoms. However, it remains unclear whether neurofeedback is of additional value to treatment as usual (TAU) for adolescents with clinical ADHD symptoms. Using a multicenter parallel-randomized controlled trial design, adolescents with ADHD symptoms were randomized to receive either a combination of TAU and neurofeedback (NFB + TAU, n = 45) or TAU-only (n = 26). Randomization was computer generated and stratified for age group (ages 12 through 16, 16 through 20, 20 through 24). Neurofeedback treatment consisted of approximately 37 sessions of theta/sensorimotor rhythm (SMR)-training on the vertex (Cz). Primary behavioral outcome measures included the ADHD-rating scale, Youth Self Report, and Child Behavior Checklist all assessed pre- and post-intervention. Behavioral problems decreased equally for both groups with medium to large effect sizes, range of partial η2 = 0.08-0.31, p neurofeedback and TAU was as effective as TAU-only for adolescents with ADHD symptoms. Considering the absence of additional behavioral effects in the current study, in combination with the limited knowledge of specific treatment effects, it is questionable whether theta/SMR neurofeedback for adolescents with ADHD and comorbid disorders in clinical practice should be used. Further research is warranted to investigate possible working mechanisms and (long-term) specific treatment effects of neurofeedback.

Role of Statistical Random-Effects Linear Models in Personalized Medicine.

Science.gov (United States)

Diaz, Francisco J; Yeh, Hung-Wen; de Leon, Jose

2012-03-01

Some empirical studies and recent developments in pharmacokinetic theory suggest that statistical random-effects linear models are valuable tools that allow describing simultaneously patient populations as a whole and patients as individuals. This remarkable characteristic indicates that these models may be useful in the development of personalized medicine, which aims at finding treatment regimes that are appropriate for particular patients, not just appropriate for the average patient. In fact, published developments show that random-effects linear models may provide a solid theoretical framework for drug dosage individualization in chronic diseases. In particular, individualized dosages computed with these models by means of an empirical Bayesian approach may produce better results than dosages computed with some methods routinely used in therapeutic drug monitoring. This is further supported by published empirical and theoretical findings that show that random effects linear models may provide accurate representations of phase III and IV steady-state pharmacokinetic data, and may be useful for dosage computations. These models have applications in the design of clinical algorithms for drug dosage individualization in chronic diseases; in the computation of dose correction factors; computation of the minimum number of blood samples from a patient that are necessary for calculating an optimal individualized drug dosage in therapeutic drug monitoring; measure of the clinical importance of clinical, demographic, environmental or genetic covariates; study of drug-drug interactions in clinical settings; the implementation of computational tools for web-site-based evidence farming; design of pharmacogenomic studies; and in the development of a pharmacological theory of dosage individualization.

Using observation-level random effects to model overdispersion in count data in ecology and evolution

Directory of Open Access Journals (Sweden)

Xavier A. Harrison

2014-10-01

Full Text Available Overdispersion is common in models of count data in ecology and evolutionary biology, and can occur due to missing covariates, non-independent (aggregated data, or an excess frequency of zeroes (zero-inflation. Accounting for overdispersion in such models is vital, as failing to do so can lead to biased parameter estimates, and false conclusions regarding hypotheses of interest. Observation-level random effects (OLRE, where each data point receives a unique level of a random effect that models the extra-Poisson variation present in the data, are commonly employed to cope with overdispersion in count data. However studies investigating the efficacy of observation-level random effects as a means to deal with overdispersion are scarce. Here I use simulations to show that in cases where overdispersion is caused by random extra-Poisson noise, or aggregation in the count data, observation-level random effects yield more accurate parameter estimates compared to when overdispersion is simply ignored. Conversely, OLRE fail to reduce bias in zero-inflated data, and in some cases increase bias at high levels of overdispersion. There was a positive relationship between the magnitude of overdispersion and the degree of bias in parameter estimates. Critically, the simulations reveal that failing to account for overdispersion in mixed models can erroneously inflate measures of explained variance (r2, which may lead to researchers overestimating the predictive power of variables of interest. This work suggests use of observation-level random effects provides a simple and robust means to account for overdispersion in count data, but also that their ability to minimise bias is not uniform across all types of overdispersion and must be applied judiciously.

Effect of Providing Ankle-Foot Orthoses in Patients with Acute and Subacute Stroke: a Randomized Controlled Trial : A randomized controlled trial

NARCIS (Netherlands)

Nikamp-Simons, Corien D.M.; Buurke, Jaap H.; Van Der Palen, Job; Hermens, Hermie J.; Rietman, Johan S.; Ibánez, Jaime; Azorín, José María; Akay, Metin; Pons, José Luis

2017-01-01

Despite frequent application of ankle-foot orthoses (AFOs), little scientific evidence is available to guide AFO-provision early after stroke. A randomized controlled trial was conducted to study the effects of AFO-provision in (sub-) acute stroke patients. Primary aim: to study effects of the

The Effect of Some Estimators of Between-Study Variance on Random

African Journals Online (AJOL)

Samson Henry Dogo

the first step to such objectivity (Schmidt, 1992), allows to combine results from many studies and accurately ... Schmidt, 2000) due to its ability to account for variation in effects across the studies. Random-effects model ... (2015), and each of the estimators differs in terms of their bias and precision in estimation. By definition ...

Coordinate based random effect size meta-analysis of neuroimaging studies.

Science.gov (United States)

Tench, C R; Tanasescu, Radu; Constantinescu, C S; Auer, D P; Cottam, W J

2017-06-01

Low power in neuroimaging studies can make them difficult to interpret, and Coordinate based meta-analysis (CBMA) may go some way to mitigating this issue. CBMA has been used in many analyses to detect where published functional MRI or voxel-based morphometry studies testing similar hypotheses report significant summary results (coordinates) consistently. Only the reported coordinates and possibly t statistics are analysed, and statistical significance of clusters is determined by coordinate density. Here a method of performing coordinate based random effect size meta-analysis and meta-regression is introduced. The algorithm (ClusterZ) analyses both coordinates and reported t statistic or Z score, standardised by the number of subjects. Statistical significance is determined not by coordinate density, but by a random effects meta-analyses of reported effects performed cluster-wise using standard statistical methods and taking account of censoring inherent in the published summary results. Type 1 error control is achieved using the false cluster discovery rate (FCDR), which is based on the false discovery rate. This controls both the family wise error rate under the null hypothesis that coordinates are randomly drawn from a standard stereotaxic space, and the proportion of significant clusters that are expected under the null. Such control is necessary to avoid propagating and even amplifying the very issues motivating the meta-analysis in the first place. ClusterZ is demonstrated on both numerically simulated data and on real data from reports of grey matter loss in multiple sclerosis (MS) and syndromes suggestive of MS, and of painful stimulus in healthy controls. The software implementation is available to download and use freely. Copyright © 2017 Elsevier Inc. All rights reserved.

When Content Matters: The Role of Processing Code in Tactile Display Design.

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Ferris, Thomas K; Sarter, Nadine

2010-01-01

The distribution of tasks and stimuli across multiple modalities has been proposed as a means to support multitasking in data-rich environments. Recently, the tactile channel and, more specifically, communication via the use of tactile/haptic icons have received considerable interest. Past research has examined primarily the impact of concurrent task modality on the effectiveness of tactile information presentation. However, it is not well known to what extent the interpretation of iconic tactile patterns is affected by another attribute of information: the information processing codes of concurrent tasks. In two driving simulation studies (n = 25 for each), participants decoded icons composed of either spatial or nonspatial patterns of vibrations (engaging spatial and nonspatial processing code resources, respectively) while concurrently interpreting spatial or nonspatial visual task stimuli. As predicted by Multiple Resource Theory, performance was significantly worse (approximately 5-10 percent worse) when the tactile icons and visual tasks engaged the same processing code, with the overall worst performance in the spatial-spatial task pairing. The findings from these studies contribute to an improved understanding of information processing and can serve as input to multidimensional quantitative models of timesharing performance. From an applied perspective, the results suggest that competition for processing code resources warrants consideration, alongside other factors such as the naturalness of signal-message mapping, when designing iconic tactile displays. Nonspatially encoded tactile icons may be preferable in environments which already rely heavily on spatial processing, such as car cockpits.

93-106, 2015 93 Multilevel random effect and marginal models

African Journals Online (AJOL)

injected by the candidate vaccine have a lower or higher risk for the occurrence of ... outcome relationship and test whether subjects inject- ... contains an agent that resembles a disease-causing ... to have different random effect variability at each cat- ... In the marginal models settings, the responses are ... Behavior as usual.

Spatial working memory load affects counting but not subitizing in enumeration.

Science.gov (United States)

Shimomura, Tomonari; Kumada, Takatsune

2011-08-01

The present study investigated whether subitizing reflects capacity limitations associated with two types of working memory tasks. Under a dual-task situation, participants performed an enumeration task in conjunction with either a spatial (Experiment 1) or a nonspatial visual (Experiment 2) working memory task. Experiment 1 showed that spatial working memory load affected the slope of a counting function but did not affect subitizing performance or subitizing range. Experiment 2 showed that nonspatial visual working memory load affected neither enumeration efficiency nor subitizing range. Furthermore, in both spatial and nonspatial memory tasks, neither subitizing efficiency nor subitizing range was affected by amount of imposed memory load. In all the experiments, working memory load failed to influence slope, subitizing range, or overall reaction time. These findings suggest that subitizing is performed without either spatial or nonspatial working memory. A possible mechanism of subitizing with independent capacity of working memory is discussed.

Self-Powered Random Number Generator Based on Coupled Triboelectric and Electrostatic Induction Effects at the Liquid-Dielectric Interface.

Science.gov (United States)

Yu, Aifang; Chen, Xiangyu; Cui, Haotian; Chen, Libo; Luo, Jianjun; Tang, Wei; Peng, Mingzeng; Zhang, Yang; Zhai, Junyi; Wang, Zhong Lin

2016-12-27

Modern cryptography increasingly employs random numbers generated from physical sources in lieu of conventional software-based pseudorandom numbers, primarily owing to the great demand of unpredictable, indecipherable cryptographic keys from true random numbers for information security. Thus, far, the sole demonstration of true random numbers has been generated through thermal noise and/or quantum effects, which suffers from expensive and complex equipment. In this paper, we demonstrate a method for self-powered creation of true random numbers by using triboelectric technology to collect random signals from nature. This random number generator based on coupled triboelectric and electrostatic induction effects at the liquid-dielectric interface includes an elaborately designed triboelectric generator (TENG) with an irregular grating structure, an electronic-optical device, and an optical-electronic device. The random characteristics of raindrops are harvested through TENG and consequently transformed and converted by electronic-optical device and an optical-electronic device with a nonlinear characteristic. The cooperation of the mechanical, electrical, and optical signals ensures that the generator possesses complex nonlinear input-output behavior and contributes to increased randomness. The random number sequences are deduced from final electrical signals received by an optical-electronic device using a familiar algorithm. These obtained random number sequences exhibit good statistical characteristics, unpredictability, and unrepeatability. Our study supplies a simple, practical, and effective method to generate true random numbers, which can be widely used in cryptographic protocols, digital signatures, authentication, identification, and other information security fields.

Nonspatial intermodal selective attention is mediated by sensory brain areas: Evidence from event-related potentials

NARCIS (Netherlands)

Talsma, D.; Kok, Albert

2001-01-01

The present study focuses on the question of whether inter- and intramodal forms of attention are reflected in activation of the same or different brain areas. ERPs were recorded while subjects were presented a random sequence of visual and auditory stimuli. They were instructed to attend to

Logistic Regression with Multiple Random Effects: A Simulation Study of Estimation Methods and Statistical Packages

Science.gov (United States)

Kim, Yoonsang; Emery, Sherry

2013-01-01

Several statistical packages are capable of estimating generalized linear mixed models and these packages provide one or more of three estimation methods: penalized quasi-likelihood, Laplace, and Gauss-Hermite. Many studies have investigated these methods’ performance for the mixed-effects logistic regression model. However, the authors focused on models with one or two random effects and assumed a simple covariance structure between them, which may not be realistic. When there are multiple correlated random effects in a model, the computation becomes intensive, and often an algorithm fails to converge. Moreover, in our analysis of smoking status and exposure to anti-tobacco advertisements, we have observed that when a model included multiple random effects, parameter estimates varied considerably from one statistical package to another even when using the same estimation method. This article presents a comprehensive review of the advantages and disadvantages of each estimation method. In addition, we compare the performances of the three methods across statistical packages via simulation, which involves two- and three-level logistic regression models with at least three correlated random effects. We apply our findings to a real dataset. Our results suggest that two packages—SAS GLIMMIX Laplace and SuperMix Gaussian quadrature—perform well in terms of accuracy, precision, convergence rates, and computing speed. We also discuss the strengths and weaknesses of the two packages in regard to sample sizes. PMID:24288415

Logistic Regression with Multiple Random Effects: A Simulation Study of Estimation Methods and Statistical Packages.

Science.gov (United States)

Kim, Yoonsang; Choi, Young-Ku; Emery, Sherry

2013-08-01

Several statistical packages are capable of estimating generalized linear mixed models and these packages provide one or more of three estimation methods: penalized quasi-likelihood, Laplace, and Gauss-Hermite. Many studies have investigated these methods' performance for the mixed-effects logistic regression model. However, the authors focused on models with one or two random effects and assumed a simple covariance structure between them, which may not be realistic. When there are multiple correlated random effects in a model, the computation becomes intensive, and often an algorithm fails to converge. Moreover, in our analysis of smoking status and exposure to anti-tobacco advertisements, we have observed that when a model included multiple random effects, parameter estimates varied considerably from one statistical package to another even when using the same estimation method. This article presents a comprehensive review of the advantages and disadvantages of each estimation method. In addition, we compare the performances of the three methods across statistical packages via simulation, which involves two- and three-level logistic regression models with at least three correlated random effects. We apply our findings to a real dataset. Our results suggest that two packages-SAS GLIMMIX Laplace and SuperMix Gaussian quadrature-perform well in terms of accuracy, precision, convergence rates, and computing speed. We also discuss the strengths and weaknesses of the two packages in regard to sample sizes.

Effect of randomness on multi-frequency aeroelastic responses resolved by Unsteady Adaptive Stochastic Finite Elements

International Nuclear Information System (INIS)

Witteveen, Jeroen A.S.; Bijl, Hester

2009-01-01

The Unsteady Adaptive Stochastic Finite Elements (UASFE) method resolves the effect of randomness in numerical simulations of single-mode aeroelastic responses with a constant accuracy in time for a constant number of samples. In this paper, the UASFE framework is extended to multi-frequency responses and continuous structures by employing a wavelet decomposition pre-processing step to decompose the sampled multi-frequency signals into single-frequency components. The effect of the randomness on the multi-frequency response is then obtained by summing the results of the UASFE interpolation at constant phase for the different frequency components. Results for multi-frequency responses and continuous structures show a three orders of magnitude reduction of computational costs compared to crude Monte Carlo simulations in a harmonically forced oscillator, a flutter panel problem, and the three-dimensional transonic AGARD 445.6 wing aeroelastic benchmark subject to random fields and random parameters with various probability distributions.

Generalized linear models with random effects unified analysis via H-likelihood

CERN Document Server

Lee, Youngjo; Pawitan, Yudi

2006-01-01

Since their introduction in 1972, generalized linear models (GLMs) have proven useful in the generalization of classical normal models. Presenting methods for fitting GLMs with random effects to data, Generalized Linear Models with Random Effects: Unified Analysis via H-likelihood explores a wide range of applications, including combining information over trials (meta-analysis), analysis of frailty models for survival data, genetic epidemiology, and analysis of spatial and temporal models with correlated errors.Written by pioneering authorities in the field, this reference provides an introduction to various theories and examines likelihood inference and GLMs. The authors show how to extend the class of GLMs while retaining as much simplicity as possible. By maximizing and deriving other quantities from h-likelihood, they also demonstrate how to use a single algorithm for all members of the class, resulting in a faster algorithm as compared to existing alternatives. Complementing theory with examples, many of...

The effects of landscape modifications on the long-term persistence of animal populations.

Directory of Open Access Journals (Sweden)

Jacob Nabe-Nielsen

Full Text Available BACKGROUND: The effects of landscape modifications on the long-term persistence of wild animal populations is of crucial importance to wildlife managers and conservation biologists, but obtaining experimental evidence using real landscapes is usually impossible. To circumvent this problem we used individual-based models (IBMs of interacting animals in experimental modifications of a real Danish landscape. The models incorporate as much as possible of the behaviour and ecology of four species with contrasting life-history characteristics: skylark (Alauda arvensis, vole (Microtus agrestis, a ground beetle (Bembidion lampros and a linyphiid spider (Erigone atra. This allows us to quantify the population implications of experimental modifications of landscape configuration and composition. METHODOLOGY/PRINCIPAL FINDINGS: Starting with a real agricultural landscape, we progressively reduced landscape complexity by (i homogenizing habitat patch shapes, (ii randomizing the locations of the patches, and (iii randomizing the size of the patches. The first two steps increased landscape fragmentation. We assessed the effects of these manipulations on the long-term persistence of animal populations by measuring equilibrium population sizes and time to recovery after disturbance. Patch rearrangement and the presence of corridors had a large effect on the population dynamics of species whose local success depends on the surrounding terrain. Landscape modifications that reduced population sizes increased recovery times in the short-dispersing species, making small populations vulnerable to increasing disturbance. The species that were most strongly affected by large disturbances fluctuated little in population sizes in years when no perturbations took place. SIGNIFICANCE: Traditional approaches to the management and conservation of populations use either classical methods of population analysis, which fail to adequately account for the spatial configurations

Effect of Randomness in Element Position on Performance of Communication Array Antennas in Internet of Things

Directory of Open Access Journals (Sweden)

Congsi Wang

2018-01-01

Full Text Available As a critical component for wireless communication, active phased array antennas face the restrictions of creating effective performance with the effect of randomness in the position of the array element, which are inevitably produced in the manufacturing and operating process of antenna. A new method for efficiently and effectively evaluating the statistic performance of antenna is presented, with consideration of randomness in element position. A coupled structural-electromagnetic statistic model for array antenna is proposed from the viewpoint of electromechanical coupling. Lastly, a 12×12 planar array is illustrated to evaluate the performance of antenna with the saddle-shaped distortion and random position error. The results show that the presented model can obtain the antenna performance quickly and effectively, providing an advantageous guidance for structural design and performance optimization for array antennas in wireless application.

Cross over of recurrence networks to random graphs and random ...

Indian Academy of Sciences (India)

2017-01-27

Jan 27, 2017 ... that all recurrence networks can cross over to random geometric graphs by adding sufficient amount of noise to .... municative [19] or social [20], deviate from the random ..... He has shown that the spatial effects become.

Generated effect modifiers (GEM's) in randomized clinical trials.

Science.gov (United States)

Petkova, Eva; Tarpey, Thaddeus; Su, Zhe; Ogden, R Todd

2017-01-01

In a randomized clinical trial (RCT), it is often of interest not only to estimate the effect of various treatments on the outcome, but also to determine whether any patient characteristic has a different relationship with the outcome, depending on treatment. In regression models for the outcome, if there is a non-zero interaction between treatment and a predictor, that predictor is called an "effect modifier". Identification of such effect modifiers is crucial as we move towards precision medicine, that is, optimizing individual treatment assignment based on patient measurements assessed when presenting for treatment. In most settings, there will be several baseline predictor variables that could potentially modify the treatment effects. This article proposes optimal methods of constructing a composite variable (defined as a linear combination of pre-treatment patient characteristics) in order to generate an effect modifier in an RCT setting. Several criteria are considered for generating effect modifiers and their performance is studied via simulations. An example from a RCT is provided for illustration. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

The Clinical Effectiveness and Cost-Effectiveness of Lamotrigine in Borderline Personality Disorder: A Randomized Placebo-Controlled Trial.

Science.gov (United States)

Crawford, Mike J; Sanatinia, Rahil; Barrett, Barbara; Cunningham, Gillian; Dale, Oliver; Ganguli, Poushali; Lawrence-Smith, Geoff; Leeson, Verity; Lemonsky, Fenella; Lykomitrou, Georgia; Montgomery, Alan A; Morriss, Richard; Munjiza, Jasna; Paton, Carol; Skorodzien, Iwona; Singh, Vineet; Tan, Wei; Tyrer, Peter; Reilly, Joseph G

2018-04-06

The authors examined whether lamotrigine is a clinically effective and cost-effective treatment for people with borderline personality disorder. This was a multicenter, double-blind, placebo-controlled randomized trial. Between July 2013 and November 2016, the authors recruited 276 people age 18 or over who met diagnostic criteria for borderline personality disorder. Individuals with coexisting bipolar affective disorder or psychosis, those already taking a mood stabilizer, and women at risk of pregnancy were excluded. A web-based randomization service was used to allocate participants randomly in a 1:1 ratio to receive either an inert placebo or up to 400 mg/day of lamotrigine. The primary outcome measure was score on the Zanarini Rating Scale for Borderline Personality Disorder (ZAN-BPD) at 52 weeks. Secondary outcome measures included depressive symptoms, deliberate self-harm, social functioning, health-related quality of life, resource use and costs, side effects of treatment, and adverse events. A total of 195 (70.6%) participants were followed up at 52 weeks, at which point 49 (36%) of those in the lamotrigine group and 58 (42%) of those in the placebo group were taking study medication. The mean ZAN-BPD score was 11.3 (SD=6.6) among those in the lamotrigine group and 11.5 (SD=7.7) among those in the placebo group (adjusted difference in means=0.1, 95% CI=-1.8, 2.0). There was no evidence of any differences in secondary outcomes. Costs of direct care were similar in the two groups. The results suggest that treating people with borderline personality disorder with lamotrigine is not a clinically effective or cost-effective use of resources.

A prototype feature system for feature retrieval using relationships

Science.gov (United States)

Choi, J.; Usery, E.L.

2009-01-01

Using a feature data model, geographic phenomena can be represented effectively by integrating space, theme, and time. This paper extends and implements a feature data model that supports query and visualization of geographic features using their non-spatial and temporal relationships. A prototype feature-oriented geographic information system (FOGIS) is then developed and storage of features named Feature Database is designed. Buildings from the U.S. Marine Corps Base, Camp Lejeune, North Carolina and subways in Chicago, Illinois are used to test the developed system. The results of the applications show the strength of the feature data model and the developed system 'FOGIS' when they utilize non-spatial and temporal relationships in order to retrieve and visualize individual features.

P2 : A random effects model with covariates for directed graphs

NARCIS (Netherlands)

van Duijn, M.A.J.; Snijders, T.A.B.; Zijlstra, B.J.H.

A random effects model is proposed for the analysis of binary dyadic data that represent a social network or directed graph, using nodal and/or dyadic attributes as covariates. The network structure is reflected by modeling the dependence between the relations to and from the same actor or node.

Approximate design theory for a simple block design with random block effects

OpenAIRE

Christof, Karin

1985-01-01

Approximate design theory for a simple block design with random block effects / K. Christof ; F. Pukelsheim. - In: Linear statistical inference / ed. by T. Calinski ... - Berlin u. a. : Springer, 1985. - S. 20-28. - (Lecture notes in statistics ; 35)

Effects of oxcarbazepine versus carbamazepine on tinnitus: A randomized double-blind placebo-controlled clinical trial

OpenAIRE

Gerami, Hooshang; Saberi, Alia; Nemati, Shadman; Kazemnejad, Ehsan; Aghajanpour, Mohammad

2012-01-01

Background: It is still a challenge to find an effective treatment for tinnitus. The aim of this study was the evaluation of carbamazepine and oxcarbazepine effects on tinnitus.Methods: In a randomized double–blind clinical trial, 57 patients who were visited in a university hospital due to chronic non-pulsatile tinnitus, were randomized in three groups and treated with carbamazepine (300-600 mg/day), oxcarbazepine (450-900 mg/day) and placebo for 12 weeks. Visual analogue scale (VAS) and tin...

Bounding the per-protocol effect in randomized trials: An application to colorectal cancer screening

NARCIS (Netherlands)

S.A. Swanson (Sonja); Holme (Øyvind); M. Løberg (Magnus); M. Kalager (Mette); M. Bretthauer (Michael); G. Hoff (G.); E. Aas (Eline); M.A. Hernán (M.)

2015-01-01

textabstractBackground: The per-protocol effect is the effect that would have been observed in a randomized trial had everybody followed the protocol. Though obtaining a valid point estimate for the per-protocol effect requires assumptions that are unverifiable and often implausible, lower and upper

The estimation of branching curves in the presence of subject-specific random effects.

Science.gov (United States)

Elmi, Angelo; Ratcliffe, Sarah J; Guo, Wensheng

2014-12-20

Branching curves are a technique for modeling curves that change trajectory at a change (branching) point. Currently, the estimation framework is limited to independent data, and smoothing splines are used for estimation. This article aims to extend the branching curve framework to the longitudinal data setting where the branching point varies by subject. If the branching point is modeled as a random effect, then the longitudinal branching curve framework is a semiparametric nonlinear mixed effects model. Given existing issues with using random effects within a smoothing spline, we express the model as a B-spline based semiparametric nonlinear mixed effects model. Simple, clever smoothness constraints are enforced on the B-splines at the change point. The method is applied to Women's Health data where we model the shape of the labor curve (cervical dilation measured longitudinally) before and after treatment with oxytocin (a labor stimulant). Copyright © 2014 John Wiley & Sons, Ltd.

Low-order non-spatial effects dominate second-order spatial effects in the texture quantifier analysis of 18F-FDG-PET images.

Directory of Open Access Journals (Sweden)

Frank J Brooks

Full Text Available There is increasing interest in applying image texture quantifiers to assess the intra-tumor heterogeneity observed in FDG-PET images of various cancers. Use of these quantifiers as prognostic indicators of disease outcome and/or treatment response has yielded inconsistent results. We study the general applicability of some well-established texture quantifiers to the image data unique to FDG-PET.We first created computer-simulated test images with statistical properties consistent with clinical image data for cancers of the uterine cervix. We specifically isolated second-order statistical effects from low-order effects and analyzed the resulting variation in common texture quantifiers in response to contrived image variations. We then analyzed the quantifiers computed for FIGOIIb cervical cancers via receiver operating characteristic (ROC curves and via contingency table analysis of detrended quantifier values.We found that image texture quantifiers depend strongly on low-effects such as tumor volume and SUV distribution. When low-order effects are controlled, the image texture quantifiers tested were not able to discern only the second-order effects. Furthermore, the results of clinical tumor heterogeneity studies might be tunable via choice of patient population analyzed.Some image texture quantifiers are strongly affected by factors distinct from the second-order effects researchers ostensibly seek to assess via those quantifiers.

Effectiveness and Cost-Effectiveness of Different Weekly Frequencies of Pilates for Chronic Low Back Pain: Randomized Controlled Trial.

Science.gov (United States)

Miyamoto, Gisela Cristiane; Moura, Katherinne Ferro; Franco, Yuri Rafael dos Santos; Oliveira, Naiane Teixeira Bastos de; Amaral, Diego Diulgeroglo Vicco; Branco, Amanda Nery Castelo; Silva, Maria Liliane da; Lin, Christine; Cabral, Cristina Maria Nunes

2016-03-01

The Pilates method has been recommended to patients with low back pain, but the evidence on effectiveness is inconclusive. In addition, there is still no evidence for the cost-effectiveness of this method or for the ideal number of sessions to achieve the highest effectiveness. The aim of this study will be to investigate the effectiveness and cost-effectiveness of the Pilates method with different weekly frequencies in the treatment of patients with nonspecific low back pain. This is a randomized controlled trial with blinded assessor. This study will be conducted at a physical therapy clinic in São Paulo, Brazil. Two hundred ninety-six patients with nonspecific low back pain between the ages of 18 and 80 years will be assessed and randomly allocated to 4 groups (n=74 patients per group). All groups will receive an educational booklet. The booklet group will not receive additional exercises. Pilates group 1 will follow a Pilates-based program once a week, Pilates group 2 will follow the same program twice a week, and Pilates group 3 will follow the same program 3 times a week. The intervention will last 6 weeks. A blinded assessor will evaluate pain, quality-adjusted life-years, general and specific disability, kinesiophobia, pain catastrophizing, and global perceived effect 6 weeks, 6 months, and 12 months after randomization. Therapists and patients will not be blinded. This will be the first study to investigate different weekly frequencies of treatment sessions for nonspecific low back pain. The results of this study will contribute to a better definition of treatment programs for this population. © 2016 American Physical Therapy Association.

Efficacy of the LiSN & Learn auditory training software: randomized blinded controlled study

Directory of Open Access Journals (Sweden)

Sharon Cameron

2012-09-01

Full Text Available Children with a spatial processing disorder (SPD require a more favorable signal-to-noise ratio in the classroom because they have difficulty perceiving sound source location cues. Previous research has shown that a novel training program - LiSN & Learn - employing spatialized sound, overcomes this deficit. Here we investigate whether improvements in spatial processing ability are specific to the LiSN & Learn training program. Participants were ten children (aged between 6;0 [years;months] and 9;9 with normal peripheral hearing who were diagnosed as having SPD using the Listening in Spatialized Noise - Sentences test (LiSN-S. In a blinded controlled study, the participants were randomly allocated to train with either the LiSN & Learn or another auditory training program - Earobics - for approximately 15 min per day for twelve weeks. There was a significant improvement post-training on the conditions of the LiSN-S that evaluate spatial processing ability for the LiSN & Learn group (P=0.03 to 0.0008, η 2=0.75 to 0.95, n=5, but not for the Earobics group (P=0.5 to 0.7, η 2=0.1 to 0.04, n=5. Results from questionnaires completed by the participants and their parents and teachers revealed improvements in real-world listening performance post-training were greater in the LiSN & Learn group than the Earobics group. LiSN & Learn training improved binaural processing ability in children with SPD, enhancing their ability to understand speech in noise. Exposure to non-spatialized auditory training does not produce similar outcomes, emphasizing the importance of deficit-specific remediation.

Efficacy of the LiSN & Learn Auditory Training Software: randomized blinded controlled study

Directory of Open Access Journals (Sweden)

Sharon Cameron

2012-01-01

Full Text Available Background: Children with a spatial processing disorder (SPD require a more favorable signal-to-noise ratio in the classroom because they have difficulty perceiving sound source location cues. Previous research has shown that a novel training program - LiSN & Learn - employing spatialized sound, overcomes this deficit. Here we investigate whether improvements in spatial processing ability are specific to the LiSN & Learn training program. Materials and methods: Participants were ten children (aged between 6;0 [years;months] and 9;9 with normal peripheral hearing who were diagnosed as having SPD using the Listening in Spatialized Noise – Sentences Test (LISN-S. In a blinded controlled study, the participants were randomly allocated to train with either the LiSN & Learn or another auditory training program – Earobics - for approximately 15 minutes per day for twelve weeks. Results: There was a significant improvement post-training on the conditions of the LiSN-S that evaluate spatial processing ability for the LiSN & Learn group (p=0.03 to 0.0008, η2=0.75 to 0.95, n=5, but not for the Earobics group (p=0.5 to 0.7, η2=0.1 to 0.04, n=5. Results from questionnaires completed by the participants and their parents and teachers revealed improvements in real-world listening performance post-training were greater in the LiSN & Learn group than the Earobics group. Conclusions: LiSN & Learn training improved binaural processing ability in children with SPD, enhancing their ability to understand speech in noise. Exposure to non-spatialized auditory training does not produce similar outcomes, emphasizing the importance of deficit-specific remediation.

A Fay-Herriot Model with Different Random Effect Variances

Czech Academy of Sciences Publication Activity Database

Hobza, Tomáš; Morales, D.; Herrador, M.; Esteban, M.D.

2011-01-01

Roč. 40, č. 5 (2011), s. 785-797 ISSN 0361-0926 R&D Projects: GA MŠk 1M0572 Institutional research plan: CEZ:AV0Z10750506 Keywords : small area estimation * Fay-Herriot model * Linear mixed model * Labor Force Survey Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 0.274, year: 2011 http://library.utia.cas.cz/separaty/2011/SI/hobza-a%20fay-herriot%20model%20with%20different%20random%20effect%20variances.pdf

Semi-parametric estimation of random effects in a logistic regression model using conditional inference

DEFF Research Database (Denmark)

Petersen, Jørgen Holm

2016-01-01

This paper describes a new approach to the estimation in a logistic regression model with two crossed random effects where special interest is in estimating the variance of one of the effects while not making distributional assumptions about the other effect. A composite likelihood is studied...

Random-Effects Models for Meta-Analytic Structural Equation Modeling: Review, Issues, and Illustrations

Science.gov (United States)

Cheung, Mike W.-L.; Cheung, Shu Fai

2016-01-01

Meta-analytic structural equation modeling (MASEM) combines the techniques of meta-analysis and structural equation modeling for the purpose of synthesizing correlation or covariance matrices and fitting structural equation models on the pooled correlation or covariance matrix. Both fixed-effects and random-effects models can be defined in MASEM.…

Generated effect modifiers (GEM’s) in randomized clinical trials

Science.gov (United States)

Petkova, Eva; Tarpey, Thaddeus; Su, Zhe; Ogden, R. Todd

2017-01-01

In a randomized clinical trial (RCT), it is often of interest not only to estimate the effect of various treatments on the outcome, but also to determine whether any patient characteristic has a different relationship with the outcome, depending on treatment. In regression models for the outcome, if there is a non-zero interaction between treatment and a predictor, that predictor is called an “effect modifier”. Identification of such effect modifiers is crucial as we move towards precision medicine, that is, optimizing individual treatment assignment based on patient measurements assessed when presenting for treatment. In most settings, there will be several baseline predictor variables that could potentially modify the treatment effects. This article proposes optimal methods of constructing a composite variable (defined as a linear combination of pre-treatment patient characteristics) in order to generate an effect modifier in an RCT setting. Several criteria are considered for generating effect modifiers and their performance is studied via simulations. An example from a RCT is provided for illustration. PMID:27465235

Modeling and understanding of effects of randomness in arrays of resonant meta-atoms

DEFF Research Database (Denmark)

Tretyakov, Sergei A.; Albooyeh, Mohammad; Alitalo, Pekka

2013-01-01

In this review presentation we will discuss approaches to modeling and understanding electromagnetic properties of 2D and 3D lattices of small resonant particles (meta-atoms) in transition from regular (periodic) to random (amorphous) states. Nanostructured metasurfaces (2D) and metamaterials (3D......) are arrangements of optically small but resonant particles (meta-atoms). We will present our results on analytical modeling of metasurfaces with periodical and random arrangements of electrically and magnetically resonant meta-atoms with identical or random sizes, both for the normal and oblique-angle excitations....... We show how the electromagnetic response of metasurfaces is related to the statistical parameters of the structure. Furthermore, we will discuss the phenomenon of anti-resonance in extracted effective parameters of metamaterials and clarify its relation to the periodicity (or amorphous nature...

Regional Specific Evidence for Memory-Load Dependent Activity in the Dorsal Subiculum and the Lateral Entorhinal Cortex

Directory of Open Access Journals (Sweden)

Shih-pi Ku

2017-07-01

Full Text Available The subiculum and the lateral entorhinal cortex (LEC are the main output areas of the hippocampus which contribute to spatial and non-spatial memory. The proximal part of the subiculum (bordering CA1 receives heavy projections from the perirhinal cortex and the distal part of CA1 (bordering the subiculum, both known for their ties to object recognition memory. However, the extent to which the proximal subiculum contributes to non-spatial memory is still unclear. Comparatively, the involvement of the LEC in non-spatial information processing is quite well known. However, very few studies have investigated its role within the frame of memory function. Thus, it is not known whether its contribution depends on memory load. In addition, the deep layers of the EC have been shown to be predictive of subsequent memory performance, but not its superficial layers. Hence, here we tested the extent to which the proximal part of the subiculum and the superficial and deep layers of the LEC contribute to non-spatial memory, and whether this contribution depends on the memory load of the task. To do so, we imaged brain activity at cellular resolution in these areas in rats performing a delayed nonmatch to sample task based on odors with two different memory loads (5 or 10 odors. This imaging technique is based on the detection of the RNA of the immediate-early gene Arc, which is especially tied to synaptic plasticity and behavioral demands, and is commonly used to map activity in the medial temporal lobe. We report for the first time that the proximal part of the subiculum is recruited in a memory-load dependent manner and the deep layers of the LEC engaged under high memory load conditions during the retrieval of non-spatial memory, thus shedding light on the specific networks contributing to non-spatial memory retrieval.

Regional Specific Evidence for Memory-Load Dependent Activity in the Dorsal Subiculum and the Lateral Entorhinal Cortex.

Science.gov (United States)

Ku, Shih-Pi; Nakamura, Nozomu H; Maingret, Nicolas; Mahnke, Liv; Yoshida, Motoharu; Sauvage, Magdalena M

2017-01-01

The subiculum and the lateral entorhinal cortex (LEC) are the main output areas of the hippocampus which contribute to spatial and non-spatial memory. The proximal part of the subiculum (bordering CA1) receives heavy projections from the perirhinal cortex and the distal part of CA1 (bordering the subiculum), both known for their ties to object recognition memory. However, the extent to which the proximal subiculum contributes to non-spatial memory is still unclear. Comparatively, the involvement of the LEC in non-spatial information processing is quite well known. However, very few studies have investigated its role within the frame of memory function. Thus, it is not known whether its contribution depends on memory load. In addition, the deep layers of the EC have been shown to be predictive of subsequent memory performance, but not its superficial layers. Hence, here we tested the extent to which the proximal part of the subiculum and the superficial and deep layers of the LEC contribute to non-spatial memory, and whether this contribution depends on the memory load of the task. To do so, we imaged brain activity at cellular resolution in these areas in rats performing a delayed nonmatch to sample task based on odors with two different memory loads (5 or 10 odors). This imaging technique is based on the detection of the RNA of the immediate-early gene Arc , which is especially tied to synaptic plasticity and behavioral demands, and is commonly used to map activity in the medial temporal lobe. We report for the first time that the proximal part of the subiculum is recruited in a memory-load dependent manner and the deep layers of the LEC engaged under high memory load conditions during the retrieval of non-spatial memory, thus shedding light on the specific networks contributing to non-spatial memory retrieval.

Regional Specific Evidence for Memory-Load Dependent Activity in the Dorsal Subiculum and the Lateral Entorhinal Cortex

Science.gov (United States)

Ku, Shih-pi; Nakamura, Nozomu H.; Maingret, Nicolas; Mahnke, Liv; Yoshida, Motoharu; Sauvage, Magdalena M.

2017-01-01

The subiculum and the lateral entorhinal cortex (LEC) are the main output areas of the hippocampus which contribute to spatial and non-spatial memory. The proximal part of the subiculum (bordering CA1) receives heavy projections from the perirhinal cortex and the distal part of CA1 (bordering the subiculum), both known for their ties to object recognition memory. However, the extent to which the proximal subiculum contributes to non-spatial memory is still unclear. Comparatively, the involvement of the LEC in non-spatial information processing is quite well known. However, very few studies have investigated its role within the frame of memory function. Thus, it is not known whether its contribution depends on memory load. In addition, the deep layers of the EC have been shown to be predictive of subsequent memory performance, but not its superficial layers. Hence, here we tested the extent to which the proximal part of the subiculum and the superficial and deep layers of the LEC contribute to non-spatial memory, and whether this contribution depends on the memory load of the task. To do so, we imaged brain activity at cellular resolution in these areas in rats performing a delayed nonmatch to sample task based on odors with two different memory loads (5 or 10 odors). This imaging technique is based on the detection of the RNA of the immediate-early gene Arc, which is especially tied to synaptic plasticity and behavioral demands, and is commonly used to map activity in the medial temporal lobe. We report for the first time that the proximal part of the subiculum is recruited in a memory-load dependent manner and the deep layers of the LEC engaged under high memory load conditions during the retrieval of non-spatial memory, thus shedding light on the specific networks contributing to non-spatial memory retrieval. PMID:28790897

Scent Lure Effect on Camera-Trap Based Leopard Density Estimates.

Directory of Open Access Journals (Sweden)

Alexander Richard Braczkowski

Full Text Available Density estimates for large carnivores derived from camera surveys often have wide confidence intervals due to low detection rates. Such estimates are of limited value to authorities, which require precise population estimates to inform conservation strategies. Using lures can potentially increase detection, improving the precision of estimates. However, by altering the spatio-temporal patterning of individuals across the camera array, lures may violate closure, a fundamental assumption of capture-recapture. Here, we test the effect of scent lures on the precision and veracity of density estimates derived from camera-trap surveys of a protected African leopard population. We undertook two surveys (a 'control' and 'treatment' survey on Phinda Game Reserve, South Africa. Survey design remained consistent except a scent lure was applied at camera-trap stations during the treatment survey. Lures did not affect the maximum movement distances (p = 0.96 or temporal activity of female (p = 0.12 or male leopards (p = 0.79, and the assumption of geographic closure was met for both surveys (p >0.05. The numbers of photographic captures were also similar for control and treatment surveys (p = 0.90. Accordingly, density estimates were comparable between surveys (although estimates derived using non-spatial methods (7.28-9.28 leopards/100km2 were considerably higher than estimates from spatially-explicit methods (3.40-3.65 leopards/100km2. The precision of estimates from the control and treatment surveys, were also comparable and this applied to both non-spatial and spatial methods of estimation. Our findings suggest that at least in the context of leopard research in productive habitats, the use of lures is not warranted.

Coherent light scattering of heterogeneous randomly rough films and effective medium in the theory of electromagnetic wave multiple scattering

Energy Technology Data Exchange (ETDEWEB)

Berginc, G [THALES, 2 avenue Gay-Lussac 78995 ELANCOURT (France)

2013-11-30

We have developed a general formalism based on Green's functions to calculate the coherent electromagnetic field scattered by a random medium with rough boundaries. The approximate expression derived makes it possible to determine the effective permittivity, which is generalised for a layer of an inhomogeneous random medium with different types of particles and bounded with randomly rough interfaces. This effective permittivity describes the coherent propagation of an electromagnetic wave in a random medium with randomly rough boundaries. We have obtained an expression, which contains the Maxwell – Garnett formula at the low-frequency limit, and the Keller formula; the latter has been proved to be in good agreement with experiments for particles whose dimensions are larger than a wavelength. (coherent light scattering)

The effectiveness of peer support groups in psychosis : a randomized controlled trial

NARCIS (Netherlands)

Castelein, S.; Bruggeman, R.; van Busschbach, J. T.; van der Gaag, M.; Stant, A. D.; Knegtering, H.; Wiersma, D.

Objective: To investigate the effect of a (minimally) guided peer support group (GPSG) for people with psychosis on social network, social support, self-efficacy, self-esteem, and quality of life, and to evaluate the intervention and its economic consequences. Method: In a multi-center randomized

Cardiac effects of granisetron in a prospective crossover randomized dose comparison trial.

Science.gov (United States)

Cakir, F B; Yapar, O; Canpolat, C; Akalin, F; Berrak, S G

2012-10-01

Cardiac side effects of granisetron have been studied mostly in adult patients that are using cardiotoxic chemotherapeutics. There is limited evidence in pediatric age group and no information in pediatric oncology patients with non-cardiotoxic chemotherapeutics. In this prospective, crossover randomized study, the cardiac side effects of granisetron are compared in pediatric oncology patients who had carboplatin based chemotherapy. They were randomized to receive either 10 or 40 μg kg(-1) dose(-1) of granisetron before each cycle of chemotherapy. We drew blood for creatine phosphokinase (CPK), CPK-muscle band (MB) and Troponin-T before and 24 h after administering granisetron. Electrocardiography (ECG) tracings were taken at 0, 1, 2, 3, 6 and 24 h of granisetron. Twenty-four hours Holter ECG monitorisation was performed after each granisetron infusion. A total of 16 patients (median 8.7 years of age) were treated with weekly consecutive courses of carboplatin. There was bradycardia (p = 0.000) in patients that had granisetron at 40 μg/kg and PR interval was shortened in patients that had granisetron at 10 μg/kg dose (p = 0.021). At both doses of granisetron, QTc interval and dispersion were found to be similar. CPK, CK-MB and Troponin-T values were found to be normal before and 24 h after granisetron infusion. As the first study that has studied cardiac side effects of granisetron in patients that are not using cardiotoxic chemotherapeutics, we conclude that granisetron at 40 μg kg(-1) dose(-1) causes bradycardia only. We have also demonstrated that granisetron does not cause any clinically cardiac side effects either at 10 or 40 μg kg(-1) dose(-1). However, our results should be supported by prospective randomized studies with larger samples of patient groups.

Curvature of random walks and random polygons in confinement

International Nuclear Information System (INIS)

Diao, Y; Ernst, C; Montemayor, A; Ziegler, U

2013-01-01

The purpose of this paper is to study the curvature of equilateral random walks and polygons that are confined in a sphere. Curvature is one of several basic geometric properties that can be used to describe random walks and polygons. We show that confinement affects curvature quite strongly, and in the limit case where the confinement diameter equals the edge length the unconfined expected curvature value doubles from π/2 to π. To study curvature a simple model of an equilateral random walk in spherical confinement in dimensions 2 and 3 is introduced. For this simple model we derive explicit integral expressions for the expected value of the total curvature in both dimensions. These expressions are functions that depend only on the radius R of the confinement sphere. We then show that the values obtained by numeric integration of these expressions agrees with numerical average curvature estimates obtained from simulations of random walks. Finally, we compare the confinement effect on curvature of random walks with random polygons. (paper)

Bayesian Nonparametric Regression Analysis of Data with Random Effects Covariates from Longitudinal Measurements

KAUST Repository

Ryu, Duchwan

2010-09-28

We consider nonparametric regression analysis in a generalized linear model (GLM) framework for data with covariates that are the subject-specific random effects of longitudinal measurements. The usual assumption that the effects of the longitudinal covariate processes are linear in the GLM may be unrealistic and if this happens it can cast doubt on the inference of observed covariate effects. Allowing the regression functions to be unknown, we propose to apply Bayesian nonparametric methods including cubic smoothing splines or P-splines for the possible nonlinearity and use an additive model in this complex setting. To improve computational efficiency, we propose the use of data-augmentation schemes. The approach allows flexible covariance structures for the random effects and within-subject measurement errors of the longitudinal processes. The posterior model space is explored through a Markov chain Monte Carlo (MCMC) sampler. The proposed methods are illustrated and compared to other approaches, the "naive" approach and the regression calibration, via simulations and by an application that investigates the relationship between obesity in adulthood and childhood growth curves. © 2010, The International Biometric Society.

A note on the effective medium theory of random resistive-reactive medium

International Nuclear Information System (INIS)

Kumar, N.; Jayannavar, A.M.

1981-06-01

The effective medium theory for a system with randomly distributed point conductivity and polarizability is re-formulated, with attention to cross-terms involving the two disorder parameters. The treatment reveals a certain inconsistency of the conventional theory owing to the neglect of the Maxwell-Wagner effect. The results are significant for the critical resistivity and dielectric anomalies of a binary liquid mixture at the phase-separation point. (author)

A Randomized Control Intervention Investigating the Effects of Acute Exercise on Emotional Regulation.

Science.gov (United States)

Edwards, Meghan K; Rhodes, Ryan E; Loprinzi, Paul D

2017-09-01

Exercise may help to cope with hectic or demanding events after a stressful situation occurs. Limited research has evaluated whether exercise, prior to a stressor, helps to facilitate subsequent emotional regulation. This pilot study addresses this novel paradigm. We employed a randomized controlled trial evaluating the effects of acute exercise on emotional regulation. Participants were randomly assigned to stretch (control group, N = 10), walk (N = 9), or jog (N = 8) for 15-minutes, after which they were exposed to a film clip intended to elicit a negative emotional response. Participants' emotions were monitored before and during exercise, as well as after the film clip. Emotional responses were evaluated using the Exercise Induced Feeling Inventory and Affective Circumplex Scale. A group x time splitplot interaction effect was significant for anger (p = .046) and anxiousness (p = .038). Follow-up analyses showed that only the stretching group (p = .048) had a significantly increased anger score from baseline to post-film clip, suggesting a protective emotional effect from walking and jogging. Exercise was effective in regulating anger and anxiousness after a stressful event. These findings provide evidence for potential preventive effects of exercise in facilitating emotional regulation.

Interaction between the nature of the information and the cognitive requirement of the task in problem solving in mice.

Science.gov (United States)

Wolff, Mathieu; Benhassine, Narimane; Costet, Pierre; Segu, Louis; Buhot, Marie-Christine

2004-11-01

The Morris water maze and the radial-arm maze are two of the most frequently employed behavioral tasks used to assess spatial memory in rodents. In this study, we describe two new behavioral tasks in a radial-arm water maze enabling to combine the advantages of the Morris water maze and the radial-arm maze. In both tasks, spatial and nonspatial learning was assessed and the only task parameter that varied was the nature of the information available which was either spatial (various distal extra-maze cues) or nonspatial (visual intra-maze patterns). In experiment 1, 129T2/Sv mice were able to learn three successive pairwise discriminations [(1) A+/B-, (2) B+/C-, (3) C+/A-] with the same efficiency in both modalities (i.e. spatial and nonspatial modalities). Probe-trials at the end of each of these discriminations revealed particular features of this transverse-patterning-like procedure. In experiment 2, another group of 129T2/Sv mice was submitted to a delayed matching-to-sample working memory task. Mice were able to learn the task and were then able to show resistance to temporal interference as long as 60 min in the spatial modality but they failed to acquire the task in the nonspatial modality. The fact that the nonspatial information was exactly the same in both experiments highlights the existence of an interaction between the cognitive requirements of the task and the nature of the information.

Components of effective randomized controlled trials of hydrotherapy programs for fibromyalgia syndrome: A systematic review

OpenAIRE

Perraton, Luke; Machotka, Zuzana; Kumar, Saravana

2009-01-01

Luke Perraton, Zuzana Machotka, Saravana KumarInternational Centre for Allied Health Evidence, University of South Australia, Adelaide, South Australia, AustraliaAim: Previous systematic reviews have found hydrotherapy to be an effective management strategy for fibromyalgia syndrome (FMS). The aim of this systematic review was to summarize the components of hydrotherapy programs used in randomized controlled trials.Method: A systematic review of randomized controlled trials was conducted. Onl...

An effective approach to attenuate random noise based on compressive sensing and curvelet transform

International Nuclear Information System (INIS)

Liu, Wei; Cao, Siyuan; Zu, Shaohuan; Chen, Yangkang

2016-01-01

Random noise attenuation is an important step in seismic data processing. In this paper, we propose a novel denoising approach based on compressive sensing and the curvelet transform. We formulate the random noise attenuation problem as an L _1 norm regularized optimization problem. We propose to use the curvelet transform as the sparse transform in the optimization problem to regularize the sparse coefficients in order to separate signal and noise and to use the gradient projection for sparse reconstruction (GPSR) algorithm to solve the formulated optimization problem with an easy implementation and a fast convergence. We tested the performance of our proposed approach on both synthetic and field seismic data. Numerical results show that the proposed approach can effectively suppress the distortion near the edge of seismic events during the noise attenuation process and has high computational efficiency compared with the traditional curvelet thresholding and iterative soft thresholding based denoising methods. Besides, compared with f-x deconvolution, the proposed denoising method is capable of eliminating the random noise more effectively while preserving more useful signals. (paper)

The effect of hormone replacement therapy on serum homocysteine levels in perimenopausal women : a randomized controlled trial

NARCIS (Netherlands)

Hak, AE; Bak, AAA; Lindemans, J; Planellas, J; Bennink, HJTC; Hofman, A; Grobbee, DE; Witteman, JCM

2001-01-01

Serum homocysteine levels may be lowered by hormone replacement therapy, but randomized controlled trial data are scarce. We performed a single center randomized placebo-controlled trial to assess the 6 months effect of hormone replacement therapy compared with placebo on fasting serum homocysteine

Effect of random microstructure on crack propagation in cortical bone tissue under dynamic loading

International Nuclear Information System (INIS)

Gao, X; Li, S; Adel-Wahab, A; Silberschmidt, V

2013-01-01

A fracture process in a cortical bone tissue depends on various factors, such as bone loss, heterogeneous microstructure, variation of its material properties and accumulation of microcracks. Therefore, it is crucial to comprehend and describe the effect of microstructure and material properties of the components of cortical bone on crack propagation in a dynamic loading regime. At the microscale level, osteonal bone demonstrates a random distribution of osteons imbedded in an interstitial matrix and surrounded by a thin layer known as cement line. Such a distribution of osteons can lead to localization of deformation processes. The global mechanical behavior of bone and the crack-propagation process are affected by such localization under external loads. Hence, the random distribution of microstructural features plays a key role in the fracture process of cortical bone. The purpose of this study is two-fold: firstly, to develop two-dimensional microstructured numerical models of cortical bone tissue in order to examine the interaction between the propagating crack and bone microstructure using an extended finite-element method under both quasi-static and dynamic loading conditions; secondly, to investigate the effect of randomly distributed microstructural constituents on the crack propagation processes and crack paths. The obtained results of numerical simulations showed the influence of random microstructure on the global response of bone tissue at macroscale and on the crack-propagation process for quasi-static and dynamic loading conditions

Effects of gut-directed hypnotherapy on IBS in different clinical settings-results from two randomized, controlled trials.

Science.gov (United States)

Lindfors, Perjohan; Unge, Peter; Arvidsson, Patrik; Nyhlin, Henry; Björnsson, Einar; Abrahamsson, Hasse; Simrén, Magnus

2012-02-01

Gut-directed hypnotherapy has been found to be effective in irritable bowel syndrome (IBS). However, randomized, controlled studies are rare and few have been performed outside highly specialized research centers. The objective of this study was to study the effect of gut-directed hypnotherapy in IBS in different clinical settings outside the traditional research units. The study population included IBS patients refractory to standard management. In study 1, patients were randomized to receive gut-directed hypnotherapy (12 sessions, 1 h/week) in psychology private practices or supportive therapy, whereas patients were randomized to receive gut-directed hypnotherapy in a small county hospital or to serve as waiting list controls in study 2. Gastrointestinal symptom severity and quality of life were evaluated at baseline, at 3 months follow-up and after 1 year. We randomized 138 IBS patients refractory to standard management, 90 in study 1 and 48 in study 2. In both the studies, IBS-related symptoms were improved at 3 months in the gut-directed hypnotherapy groups (Phypnotherapy group than in the control group (Phypnotherapy is an effective treatment alternative for patients with refractory IBS, but the effectiveness is lower when the therapy is given outside the highly specialized research centers.

Role of centrality for the identification of influential spreaders in complex networks.

Science.gov (United States)

de Arruda, Guilherme Ferraz; Barbieri, André Luiz; Rodríguez, Pablo Martín; Rodrigues, Francisco A; Moreno, Yamir; Costa, Luciano da Fontoura

2014-09-01

The identification of the most influential spreaders in networks is important to control and understand the spreading capabilities of the system as well as to ensure an efficient information diffusion such as in rumorlike dynamics. Recent works have suggested that the identification of influential spreaders is not independent of the dynamics being studied. For instance, the key disease spreaders might not necessarily be so important when it comes to analyzing social contagion or rumor propagation. Additionally, it has been shown that different metrics (degree, coreness, etc.) might identify different influential nodes even for the same dynamical processes with diverse degrees of accuracy. In this paper, we investigate how nine centrality measures correlate with the disease and rumor spreading capabilities of the nodes in different synthetic and real-world (both spatial and nonspatial) networks. We also propose a generalization of the random walk accessibility as a new centrality measure and derive analytical expressions for the latter measure for simple network configurations. Our results show that for nonspatial networks, the k-core and degree centralities are the most correlated to epidemic spreading, whereas the average neighborhood degree, the closeness centrality, and accessibility are the most related to rumor dynamics. On the contrary, for spatial networks, the accessibility measure outperforms the rest of the centrality metrics in almost all cases regardless of the kind of dynamics considered. Therefore, an important consequence of our analysis is that previous studies performed in synthetic random networks cannot be generalized to the case of spatial networks.

Estimating safety effects of pavement management factors utilizing Bayesian random effect models.

Science.gov (United States)

Jiang, Ximiao; Huang, Baoshan; Zaretzki, Russell L; Richards, Stephen; Yan, Xuedong

2013-01-01

Previous studies of pavement management factors that relate to the occurrence of traffic-related crashes are rare. Traditional research has mostly employed summary statistics of bidirectional pavement quality measurements in extended longitudinal road segments over a long time period, which may cause a loss of important information and result in biased parameter estimates. The research presented in this article focuses on crash risk of roadways with overall fair to good pavement quality. Real-time and location-specific data were employed to estimate the effects of pavement management factors on the occurrence of crashes. This research is based on the crash data and corresponding pavement quality data for the Tennessee state route highways from 2004 to 2009. The potential temporal and spatial correlations among observations caused by unobserved factors were considered. Overall 6 models were built accounting for no correlation, temporal correlation only, and both the temporal and spatial correlations. These models included Poisson, negative binomial (NB), one random effect Poisson and negative binomial (OREP, ORENB), and two random effect Poisson and negative binomial (TREP, TRENB) models. The Bayesian method was employed to construct these models. The inference is based on the posterior distribution from the Markov chain Monte Carlo (MCMC) simulation. These models were compared using the deviance information criterion. Analysis of the posterior distribution of parameter coefficients indicates that the pavement management factors indexed by Present Serviceability Index (PSI) and Pavement Distress Index (PDI) had significant impacts on the occurrence of crashes, whereas the variable rutting depth was not significant. Among other factors, lane width, median width, type of terrain, and posted speed limit were significant in affecting crash frequency. The findings of this study indicate that a reduction in pavement roughness would reduce the likelihood of traffic

Effects of Nurse-Led Multifactorial Care to Prevent Disability in Community-Living Older People : Cluster Randomized Trial

NARCIS (Netherlands)

Suijker, Jacqueline J.; van Rijn, Marjon; Buurman, Bianca M.; ter Riet, Gerben; van Charante, Eric P. Moll; de Rooij, Sophia E.

2016-01-01

Background To evaluate the effects of nurse-led multifactorial care to prevent disability in community-living older people. Methods In a cluster randomized trail, 11 practices (n = 1,209 participants) were randomized to the intervention group, and 13 practices (n = 1,074 participants) were

The Effects of Positive or Neutral Communication during Acupuncture for Relaxing Effects: A Sham-Controlled Randomized Trial

Directory of Open Access Journals (Sweden)

Annelie Rosén

2016-01-01

Full Text Available Introduction. The link between patient-clinician communication and its effect on clinical outcomes is an important clinical issue that is yet to be elucidated. Objective. Investigating if communication type (positive or neutral about the expected treatment outcome affected (i participants’ expectations and (ii short-term relaxation effects in response to genuine or sham acupuncture and investigating if expectations were related to outcome. Methods. Healthy volunteers (n=243, mean age of 42 were randomized to one treatment with genuine or sham acupuncture. Within groups, participants were randomized to positive or neutral communication, regarding expected treatment effects. Visual Analogue Scales (0–100 millimeters were used to measure treatment expectations and relaxation, directly before and after treatment. Results. Participants in the positive communication group reported higher treatment expectancy, compared to the neutral communication group (md 12 versus 6 mm, p=0.002. There was no difference in relaxation effects between acupuncture groups or between communication groups. Participants with high baseline expectancy perceived greater improvement in relaxation, compared to participants with low baseline levels (md 27 versus 15 mm, p=0.022. Conclusion. Our data highlights the importance of expectations for treatment outcome and demonstrates that expectations can be effectively manipulated using a standardized protocol that in future research may be implemented in clinical trials.

The Effectiveness of Healthy Start Home Visit Program: Cluster Randomized Controlled Trial

Science.gov (United States)

Leung, Cynthia; Tsang, Sandra; Heung, Kitty

2015-01-01

Purpose: The study reported the effectiveness of a home visit program for disadvantaged Chinese parents with preschool children, using cluster randomized controlled trial design. Method: Participants included 191 parents and their children from 24 preschools, with 84 dyads (12 preschools) in the intervention group and 107 dyads (12 preschools) in…

Effectiveness of horticultural therapy: a systematic review of randomized controlled trials.

Science.gov (United States)

Kamioka, Hiroharu; Tsutani, Kiichiro; Yamada, Minoru; Park, Hyuntae; Okuizumi, Hiroyasu; Honda, Takuya; Okada, Shinpei; Park, Sang-Jun; Kitayuguchi, Jun; Abe, Takafumi; Handa, Shuichi; Mutoh, Yoshiteru

2014-10-01

To summarize the evidence from randomized controlled trials (RCTs) on the effects of horticultural therapy (HT). Studies were eligible if they were RCTs. Studies included one treatment group in which HT was applied. We searched the following databases from 1990 up to August 20, 2013: MEDLINE via PubMed, CINAHL, Web of Science, Ichushi-Web, GHL, WPRIM, and PsyclNFO. We also searched all Cochrane Database and Campbell Systematic Reviews up to September 20, 2013. Four studies met all inclusion criteria. The language of all eligible publications was English and Korean. Target diseases and/or symptoms were dementia, severe mental illness such as schizophrenia, bipolar disorder, and major depression, frail elderly in nursing home, and hemiplegic patients after stroke. These studies showed significant effectiveness in one or more outcomes for mental health and behavior. However, our review especially detected omissions of the following descriptions: method used to generate randomization, concealment, blinding, and intention-to-treat analysis. In addition, the results of this study suggested that the RCTs conducted have been of relatively low quality. Although there was insufficient evidence in the studies of HT due to poor methodological and reporting quality and heterogeneity, HT may be an effective treatment for mental and behavioral disorders such as dementia, schizophrenia, depression, and terminal-care for cancer. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effects of Random Values for Particle Swarm Optimization Algorithm

Directory of Open Access Journals (Sweden)

Hou-Ping Dai

2018-02-01

Full Text Available Particle swarm optimization (PSO algorithm is generally improved by adaptively adjusting the inertia weight or combining with other evolution algorithms. However, in most modified PSO algorithms, the random values are always generated by uniform distribution in the range of [0, 1]. In this study, the random values, which are generated by uniform distribution in the ranges of [0, 1] and [−1, 1], and Gauss distribution with mean 0 and variance 1 ( U [ 0 , 1 ] , U [ − 1 , 1 ] and G ( 0 , 1 , are respectively used in the standard PSO and linear decreasing inertia weight (LDIW PSO algorithms. For comparison, the deterministic PSO algorithm, in which the random values are set as 0.5, is also investigated in this study. Some benchmark functions and the pressure vessel design problem are selected to test these algorithms with different types of random values in three space dimensions (10, 30, and 100. The experimental results show that the standard PSO and LDIW-PSO algorithms with random values generated by U [ − 1 , 1 ] or G ( 0 , 1 are more likely to avoid falling into local optima and quickly obtain the global optima. This is because the large-scale random values can expand the range of particle velocity to make the particle more likely to escape from local optima and obtain the global optima. Although the random values generated by U [ − 1 , 1 ] or G ( 0 , 1 are beneficial to improve the global searching ability, the local searching ability for a low dimensional practical optimization problem may be decreased due to the finite particles.

Effectiveness of Stepped Care for Chronic Fatigue Syndrome: A Randomized Noninferiority Trial

Science.gov (United States)

Tummers, Marcia; Knoop, Hans; Bleijenberg, Gijs

2010-01-01

Objective: In this randomized noninferiority study, the effectiveness and efficiency of stepped care for chronic fatigue syndrome (CFS) was compared to care as usual. Stepped care was formed by guided self-instruction, followed by cognitive behavior therapy (CBT) if the patient desired it. Care as usual encompassed CBT after a waiting period.…

Randomized controlled trial on the effects of legumes on cardiovascular risk factors in women with abdominal obesity

OpenAIRE

Safaeiyan, Abdolrasoul; Pourghassem-Gargari, Bahram; Zarrin, Rasoul; Fereidooni, Javid; Alizadeh, Mohammad

2015-01-01

BACKGROUND The effect of legume-based hypocaloric diet on cardiovascular disease (CVD) risk factors in women is unclear. This study provides an opportunity to find effects of high-legume diet on CVD risk factors in women who consumed high legumes at baseline. METHODS This randomized controlled trial was undertaken in 34 premenopausal women with central obesity. After 2 weeks of a run-in period on an isocaloric diet, subjects were randomly assigned into two groups: (1) hypocaloric diet enriche...

Randomized controlled trial on the effects of legumes on cardiovascular risk factors in women with abdominal obesity

OpenAIRE

Abdolrasoul Safaeiyan; Bahram Pourghassem-Gargari; Rasoul Zarrin; Javid Fereidooni; Mohammad Alizadeh

2015-01-01

BACKGROUND: The effect of legume-based hypocaloric diet on cardiovascular disease (CVD) risk factors in women is unclear. This study provides an opportunity to find effects of high-legume diet on CVD risk factors in women who consumed high legumes at baseline. METHODS: This randomized controlled trial was undertaken in 34 premenopausal women with central obesity. After 2 weeks of a run-in period on an isocaloric diet, subjects were randomly assigned into two groups: (1) hypocaloric diet enric...

An evaluation of the effectiveness of recruitment methods: the staying well after depression randomized controlled trial.

Science.gov (United States)

Krusche, Adele; Rudolf von Rohr, Isabelle; Muse, Kate; Duggan, Danielle; Crane, Catherine; Williams, J Mark G

2014-04-01

Randomized controlled trials (RCTs) are widely accepted as being the most efficient way of investigating the efficacy of psychological therapies. However, researchers conducting RCTs commonly report difficulties in recruiting an adequate sample within planned timescales. In an effort to overcome recruitment difficulties, researchers often are forced to expand their recruitment criteria or extend the recruitment phase, thus increasing costs and delaying publication of results. Research investigating the effectiveness of recruitment strategies is limited, and trials often fail to report sufficient details about the recruitment sources and resources utilized. We examined the efficacy of strategies implemented during the Staying Well after Depression RCT in Oxford to recruit participants with a history of recurrent depression. We describe eight recruitment methods utilized and two further sources not initiated by the research team and examine their efficacy in terms of (1) the return, including the number of potential participants who contacted the trial and the number who were randomized into the trial; (2) cost-effectiveness, comprising direct financial cost and manpower for initial contacts and randomized participants; and (3) comparison of sociodemographic characteristics of individuals recruited from different sources. Poster advertising, web-based advertising, and mental health worker referrals were the cheapest methods per randomized participant; however, the ratio of randomized participants to initial contacts differed markedly per source. Advertising online, via posters, and on a local radio station were the most cost-effective recruitment methods for soliciting participants who subsequently were randomized into the trial. Advertising across many sources (saturation) was found to be important. It may not be feasible to employ all the recruitment methods used in this trial to obtain participation from other populations, such as those currently unwell, or in

Effects of systematic phase errors on optimized quantum random-walk search algorithm

International Nuclear Information System (INIS)

Zhang Yu-Chao; Bao Wan-Su; Wang Xiang; Fu Xiang-Qun

2015-01-01

This study investigates the effects of systematic errors in phase inversions on the success rate and number of iterations in the optimized quantum random-walk search algorithm. Using the geometric description of this algorithm, a model of the algorithm with phase errors is established, and the relationship between the success rate of the algorithm, the database size, the number of iterations, and the phase error is determined. For a given database size, we obtain both the maximum success rate of the algorithm and the required number of iterations when phase errors are present in the algorithm. Analyses and numerical simulations show that the optimized quantum random-walk search algorithm is more robust against phase errors than Grover’s algorithm. (paper)

Ipsilateral transversus abdominis plane block provides effective analgesia after appendectomy in children: a randomized controlled trial.

LENUS (Irish Health Repository)

Carney, John

2010-10-01

The transversus abdominis plane (TAP) block provides effective postoperative analgesia in adults undergoing major abdominal surgery. Its efficacy in children remains unclear, with no randomized clinical trials in this population. In this study, we evaluated its analgesic efficacy over the first 48 postoperative hours after appendectomy performed through an open abdominal incision, in a randomized, controlled, double-blind clinical trial.

Effectiveness of energy conservation management on fatigue and participation in multiple sclerosis: A randomized controlled trial.

Science.gov (United States)

Blikman, Lyan Jm; van Meeteren, Jetty; Twisk, Jos Wr; de Laat, Fred Aj; de Groot, Vincent; Beckerman, Heleen; Stam, Henk J; Bussmann, Johannes Bj

2017-10-01

Fatigue is a frequently reported and disabling symptom in multiple sclerosis (MS). To investigate the effectiveness of an individual energy conservation management (ECM) intervention on fatigue and participation in persons with primary MS-related fatigue. A total of 86 severely fatigued and ambulatory adults with a definite diagnosis of MS were randomized in a single-blind, two-parallel-arm randomized clinical trial to the ECM group or the information-only control group in outpatient rehabilitation departments. Blinded assessments were carried out at baseline and at 8, 16, 26 and 52 weeks after randomization. Primary outcomes were fatigue (fatigue subscale of Checklist Individual Strength - CIS20r) and participation (Impact on Participation and Autonomy scale - IPA). Modified intention-to-treat analysis was based on 76 randomized patients (ECM, n = 36; MS nurse, n=40). No significant ECM effects were found for fatigue (overall difference CIS20r between the groups = -0.81; 95% confidence interval (CI), -3.71 to 2.11) or for four out of five IPA domains. An overall unfavourable effect was found in the ECM group for the IPA domain social relations (difference between the groups = 0.19; 95% CI, 0.03 to 0.35). The individual ECM format used in this study did not reduce MS-related fatigue and restrictions in participation more than an information-only control condition.

QT-interval effects of methadone, levomethadyl, and buprenorphine in a randomized trial.

Science.gov (United States)

Wedam, Erich F; Bigelow, George E; Johnson, Rolley E; Nuzzo, Paul A; Haigney, Mark C P

2007-12-10

Levomethadyl acetate, methadone hydrochloride, and buprenorphine hydrochloride are equally effective treatments for opioid dependence. Each blocks the human ether-a-go-go-related gene (hERG)-associated channel in vitro and represents a risk for QT prolongation. To compare the effects of 3 known hERG-associated channel blockers on the corrected QT (QTc), we conducted a randomized, controlled trial of opioid-addicted subjects. We analyzed 12-lead electrocardiograms collected at baseline and every 4 weeks from 165 opioid-addicted participants in a 17-week randomized double-blind clinical trial of equally effective doses of levomethadyl, methadone, and buprenorphine at a major referral center. Analyses were limited to the 154 patients with a normal baseline QTc = (QT/ radical R-R) who had at least 1 subsequent in-treatment electrocardiogram. Patients were randomized to receive treatment with levomethadyl, methadone, or buprenorphine (hereinafter, levomethadyl, methadone, and buprenorphine groups, respectively). The prespecified end points were a QTc greater than 470 milliseconds in men (or >490 milliseconds in women), or an increase from baseline in QTc greater than 60 milliseconds. Baseline QTc was similar in the 3 groups. The levomethadyl and methadone groups were significantly more likely to manifest a QTc greater than 470 or 490 milliseconds (28% for the levomethadyl group vs 23% for the methadone group vs 0% for the buprenorphine group; P methadone group [odds ratio, 8.4; 95% confidence interval, 1.9-36.4]) compared with the buprenorphine group (2% of subjects; P methadone remained fixed over at least 8 weeks, the QTc continued to increase progressively over time (P = .08 for the levomethadyl group, P = .01 for the methadone group). Buprenorphine is associated with less QTc prolongation than levomethadyl or methadone and may be a safe alternative.

Mediating Parent Learning to Promote Social Communication for Toddlers with Autism: Effects from a Randomized Controlled Trial

Science.gov (United States)

Schertz, Hannah H.; Odom, Samuel L.; Baggett, Kathleen M.; Sideris, John H.

2018-01-01

A randomized controlled trial was conducted to evaluate effects of the Joint Attention Mediated Learning (JAML) intervention. Toddlers with autism spectrum disorders (ASD) aged 16-30 months (n = 144) were randomized to intervention and community control conditions. Parents, who participated in 32 weekly home-based sessions, followed a mediated…

Behavioral and Brain Measures of Phasic Alerting Effects on Visual Attention.

Science.gov (United States)

Wiegand, Iris; Petersen, Anders; Finke, Kathrin; Bundesen, Claus; Lansner, Jon; Habekost, Thomas

2017-01-01

In the present study, we investigated effects of phasic alerting on visual attention in a partial report task, in which half of the displays were preceded by an auditory warning cue. Based on the computational Theory of Visual Attention (TVA), we estimated parameters of spatial and non-spatial aspects of visual attention and measured event-related lateralizations (ERLs) over visual processing areas. We found that the TVA parameter sensory effectiveness a , which is thought to reflect visual processing capacity, significantly increased with phasic alerting. By contrast, the distribution of visual processing resources according to task relevance and spatial position, as quantified in parameters top-down control α and spatial bias w index , was not modulated by phasic alerting. On the electrophysiological level, the latencies of ERLs in response to the task displays were reduced following the warning cue. These results suggest that phasic alerting facilitates visual processing in a general, unselective manner and that this effect originates in early stages of visual information processing.

Quantifying the placebo effect in psychological outcomes of exercise training: a meta-analysis of randomized trials.

Science.gov (United States)

Lindheimer, Jacob B; O'Connor, Patrick J; Dishman, Rod K

2015-05-01

The placebo effect could account for some or all of the psychological benefits attributed to exercise training. The magnitude of the placebo effect in psychological outcomes of randomized controlled exercise training trials has not been quantified. The aim of this investigation was to estimate the magnitude of the population placebo effect in psychological outcomes from placebo conditions used in exercise training studies and compare it to the observed effect of exercise training. Articles published before 1 July 2013 were located using Google Scholar, MEDLINE, PsycINFO, and The Cochrane Library. To be included in the analysis, studies were required to have (1) a design that randomly assigned participants to exercise training, placebo, and control conditions and (2) an assessment of a subjective (i.e., anxiety, depression, energy, fatigue) or an objective (i.e., cognitive) psychological outcome. Meta-analytic and multi-level modeling techniques were used to analyze effects from nine studies involving 661 participants. Hedges' d effect sizes were calculated, and random effects models were used to estimate the overall magnitude of the placebo and exercise training effects. After adjusting for nesting effects, the placebo mean effect size was 0.20 (95% confidence interval [CI] -0.02, 0.41) and the observed effect of exercise training was 0.37 (95% CI 0.11, 0.63). A small body of research suggests both that (1) the placebo effect is approximately half of the observed psychological benefits of exercise training and (2) there is an urgent need for creative research specifically aimed at better understanding the role of the placebo effect in the mental health consequences of exercise training.

The effect of financial rewards on students' achievement: Evidence from a randomized experiment

NARCIS (Netherlands)

Leuven, E.; Oosterbeek, H.; van der Klaauw, B.

2010-01-01

This paper reports on a randomized field experiment in which first-year university students could earn financial rewards for passing all first-year requirements within one year. Financial incentives turn out to have positive effects on achievement of high-ability students, whereas they have a

Generalized Dynamic Panel Data Models with Random Effects for Cross-Section and Time

NARCIS (Netherlands)

Mesters, G.; Koopman, S.J.

2014-01-01

An exact maximum likelihood method is developed for the estimation of parameters in a nonlinear non-Gaussian dynamic panel data model with unobserved random individual-specific and time-varying effects. We propose an estimation procedure based on the importance sampling technique. In particular, a

Trimethoprim-sulfamethoxazole in children with chronic otitis media: a randomized comparison of costs and effects.

NARCIS (Netherlands)

Boonacker, C.W.; Veen, E.L. van der; Wilt, G.J. van der; Schilder, A.G.M.; Rovers, M.M.

2008-01-01

OBJECTIVE: To study the cost-effectiveness of a 6- to 12-week course of high-dose oral trimethoprim-sulfamethoxazole in children with chronic active otitis media (COM). STUDY DESIGN: Cost-effectiveness study including both direct and indirect costs alongside a randomized placebo-controlled trial.

Cosmic and terrestrial single-event radiation effects in dynamic random access memories

International Nuclear Information System (INIS)

Massengill, L.W.

1996-01-01

A review of the literature on single-event radiation effects (SEE) on MOS integrated-circuit dynamic random access memories (DRAM's) is presented. The sources of single-event (SE) radiation particles, causes of circuit information loss, experimental observations of SE information upset, technological developments for error mitigation, and relationships of developmental trends to SE vulnerability are discussed

Utility and Cost-Effectiveness of Motivational Messaging to Increase Survey Response in Physicians: A Randomized Controlled Trial

Science.gov (United States)

Chan, Randolph C. H.; Mak, Winnie W. S.; Pang, Ingrid H. Y.; Wong, Samuel Y. S.; Tang, Wai Kwong; Lau, Joseph T. F.; Woo, Jean; Lee, Diana T. F.; Cheung, Fanny M.

2018-01-01

The present study examined whether, when, and how motivational messaging can boost the response rate of postal surveys for physicians based on Higgin's regulatory focus theory, accounting for its cost-effectiveness. A three-arm, blinded, randomized controlled design was used. A total of 3,270 doctors were randomly selected from the registration…

A cluster randomized controlled trial testing the effectiveness of Houvast: A strengths-based intervention for homeless young adults

NARCIS (Netherlands)

Krabbenborg, M.A.M.; Boersma, S.N.; Veld, W.M. van der; Hulst, B. van; Vollebergh, W.A.M.; Wolf, J.R.L.M.

2017-01-01

Objective: To test the effectiveness of Houvast: a strengths-based intervention for homeless young adults. Method: A cluster randomized controlled trial was conducted with 10 Dutch shelter facilities randomly allocated to an intervention and a control group. Homeless young adults were interviewed

Effects of traditional cupping therapy in patients with carpal tunnel syndrome: a randomized controlled trial.

Science.gov (United States)

Michalsen, Andreas; Bock, Silke; Lüdtke, Rainer; Rampp, Thomas; Baecker, Marcus; Bachmann, Jürgen; Langhorst, Jost; Musial, Frauke; Dobos, Gustav J

2009-06-01

We investigated the effectiveness of cupping, a traditional method of treating musculoskeletal pain, in patients with carpal tunnel syndrome (CTS) in an open randomized trial. n = 52 outpatients (58.5 +/- 8.0 years) with neurologically confirmed CTS were randomly assigned to either a verum (n = 26) or a control group (n = 26). Verum patients were treated with a single application of wet cupping, and control patients with a single local application of heat within the region overlying the trapezius muscle. Patients were followed up on day 7 after treatment. The primary outcome, severity of CTS symptoms (VAS), was reduced from 61.5 +/- 20.5 to 24.6 +/- 22.7 mm at day 7 in the cupping group and from 67.1 +/- 20.2 to 51.7 +/- 23.9 mm in the control group [group difference -24.5mm (95%CI -36.1; -2.9, P cupping therapy may be effective in relieving the pain and other symptoms related to CTS. The efficacy of cupping in the long-term management of CTS and related mechanisms remains to be clarified. The results of a randomized trial on the clinical effects of traditional cupping therapy in patients with carpal tunnel syndrome are presented. Cupping of segmentally related shoulder zones appears to alleviate the symptoms of carpal tunnel syndrome.

Effect of music in endoscopy procedures: systematic review and meta-analysis of randomized controlled trials.

Science.gov (United States)

Wang, Man Cai; Zhang, Ling Yi; Zhang, Yu Long; Zhang, Ya Wu; Xu, Xiao Dong; Zhang, You Cheng

2014-10-01

Endoscopies are common clinical examinations that are somewhat painful and even cause fear and anxiety for patients. We performed this systematic review and meta-analysis of randomized controlled trials to determine the effect of music on patients undergoing various endoscopic procedures. We searched the Cochrane Library, Issue 6, 2013, PubMed, and EMBASE databases up to July 2013. Randomized controlled trials comparing endoscopies, with and without the use of music, were included. Two authors independently abstracted data and assessed risk of bias. Subgroup analyses were performed to examine the impact of music on different types of endoscopic procedures. Twenty-one randomized controlled trials involving 2,134 patients were included. The overall effect of music on patients undergoing a variety of endoscopic procedures significantly improved pain score (weighted mean difference [WMD] = -1.53, 95% confidence interval [CI] [-2.53, -0.53]), anxiety (WMD = -6.04, 95% CI [-9.61, -2.48]), heart rate (P = 0.01), arterial pressure (P music group, compared with the control group. Furthermore, music had little effect for patients undergoing colposcopy and bronchoscopy in the subanalysis. Our meta-analysis suggested that music may offer benefits for patients undergoing endoscopy, except in colposcopy and bronchoscopy. Wiley Periodicals, Inc.

Cultivating teacher mindfulness: Effects of a randomized controlled trial on work, home, and sleep outcomes.

Science.gov (United States)

Crain, Tori L; Schonert-Reichl, Kimberly A; Roeser, Robert W

2017-04-01

The effects of randomization to a workplace mindfulness training (WMT) or a waitlist control condition on teachers' well-being (moods and satisfaction at work and home), quantity of sleep, quality of sleep, and sleepiness during the day were examined in 2 randomized, waitlist controlled trials (RCTs). The combined sample of the 2 RCTs, conducted in Canada and the United States, included 113 elementary and secondary school teachers (89% female). Measures were collected at baseline, postprogram, and 3-month follow-up; teachers were randomly assigned to condition after baseline assessment. Results showed that teachers randomized to WMT reported less frequent bad moods at work and home, greater satisfaction at work and home, more sleep on weekday nights, better quality sleep, and decreased insomnia symptoms and daytime sleepiness. Training-related group differences in mindfulness and rumination on work at home at postprogram partially mediated the reductions in negative moods at home and increases in sleep quality at follow-up. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Comparative effectiveness of childhood obesity interventions in pediatric primary care: a cluster-randomized clinical trial.

Science.gov (United States)

Taveras, Elsie M; Marshall, Richard; Kleinman, Ken P; Gillman, Matthew W; Hacker, Karen; Horan, Christine M; Smith, Renata L; Price, Sarah; Sharifi, Mona; Rifas-Shiman, Sheryl L; Simon, Steven R

2015-06-01

Evidence of effective treatment of childhood obesity in primary care settings is limited. To examine the extent to which computerized clinical decision support (CDS) delivered to pediatric clinicians at the point of care of obese children, with or without individualized family coaching, improved body mass index (BMI; calculated as weight in kilograms divided by height in meters squared) and quality of care. We conducted a cluster-randomized, 3-arm clinical trial. We enrolled 549 children aged 6 to 12 years with a BMI at the 95% percentile or higher from 14 primary care practices in Massachusetts from October 1, 2011, through June 30, 2012. Patients were followed up for 1 year (last follow-up, August 30, 2013). In intent-to-treat analyses, we used linear mixed-effects models to account for clustering by practice and within each person. In 5 practices randomized to CDS, pediatric clinicians received decision support on obesity management, and patients and their families received an intervention for self-guided behavior change. In 5 practices randomized to CDS + coaching, decision support was augmented by individualized family coaching. The remaining 4 practices were randomized to usual care. Smaller age-associated change in BMI and the Healthcare Effectiveness Data and Information Set (HEDIS) performance measures for obesity during the 1-year follow-up. At baseline, mean (SD) patient age and BMI were 9.8 (1.9) years and 25.8 (4.3), respectively. At 1 year, we obtained BMI from 518 children (94.4%) and HEDIS measures from 491 visits (89.4%). The 3 randomization arms had different effects on BMI over time (P = .04). Compared with the usual care arm, BMI increased less in children in the CDS arm during 1 year (-0.51 [95% CI, -0.91 to -0.11]). The CDS + coaching arm had a smaller magnitude of effect (-0.34 [95% CI, -0.75 to 0.07]). We found substantially greater achievement of childhood obesity HEDIS measures in the CDS arm (adjusted odds ratio, 2.28 [95% CI, 1

A randomized controlled trial of the effectiveness of multisystemic therapy in the Netherlands: post-treatment changes and moderator effects

NARCIS (Netherlands)

Asscher, J.J.; Dekovic, M.; Manders, W.A.; Prins, P.J.M.; van der Laan, P.H.

2013-01-01

Objective: In the present randomized controlled trial, the effectiveness of multisystemic therapy (MST) in The Netherlands was examined. Moderator tests were conducted for ethnicity, age and gender. Methods: The sample consisted of N = 256 adolescents, referred because of conduct problems, and

Effect of Playful Balancing Training - A Pilot Randomized Controlled Trial

DEFF Research Database (Denmark)

Lund, Henrik Hautop; Jessen, Jari Due

2013-01-01

We used the modular playware in the form of modular interactive tiles for playful training of community-dwelling elderly with balancing problem. During short-term play on the modular interactive tiles, the elderly were playing physical, interactive games that were challenging their dynamic balance...... increase in balancing performance (DGI score: 21.3) after short-term playful training with the modular interactive tiles, whereas the control group remained with a score indicating balancing problems and risk of falling (DGI score: 16.6). The small pilot randomized controlled trial suggests...... that the playful interaction with the modular interactive tiles has a significant effect even after a very short time of play. The average total training time to obtain the statistical significant effect amounted to just 2h45m....

Bayesian random-effect model for predicting outcome fraught with heterogeneity--an illustration with episodes of 44 patients with intractable epilepsy.

Science.gov (United States)

Yen, A M-F; Liou, H-H; Lin, H-L; Chen, T H-H

2006-01-01

The study aimed to develop a predictive model to deal with data fraught with heterogeneity that cannot be explained by sampling variation or measured covariates. The random-effect Poisson regression model was first proposed to deal with over-dispersion for data fraught with heterogeneity after making allowance for measured covariates. Bayesian acyclic graphic model in conjunction with Markov Chain Monte Carlo (MCMC) technique was then applied to estimate the parameters of both relevant covariates and random effect. Predictive distribution was then generated to compare the predicted with the observed for the Bayesian model with and without random effect. Data from repeated measurement of episodes among 44 patients with intractable epilepsy were used as an illustration. The application of Poisson regression without taking heterogeneity into account to epilepsy data yielded a large value of heterogeneity (heterogeneity factor = 17.90, deviance = 1485, degree of freedom (df) = 83). After taking the random effect into account, the value of heterogeneity factor was greatly reduced (heterogeneity factor = 0.52, deviance = 42.5, df = 81). The Pearson chi2 for the comparison between the expected seizure frequencies and the observed ones at two and three months of the model with and without random effect were 34.27 (p = 1.00) and 1799.90 (p dispersion attributed either to correlated property or to subject-to-subject variability.

Many multicenter trials had few events per center, requiring analysis via random-effects models or GEEs.

Science.gov (United States)

Kahan, Brennan C; Harhay, Michael O

2015-12-01

Adjustment for center in multicenter trials is recommended when there are between-center differences or when randomization has been stratified by center. However, common methods of analysis (such as fixed-effects, Mantel-Haenszel, or stratified Cox models) often require a large number of patients or events per center to perform well. We reviewed 206 multicenter randomized trials published in four general medical journals to assess the average number of patients and events per center and determine whether appropriate methods of analysis were used in trials with few patients or events per center. The median number of events per center/treatment arm combination for trials using a binary or survival outcome was 3 (interquartile range, 1-10). Sixteen percent of trials had less than 1 event per center/treatment combination, 50% fewer than 3, and 63% fewer than 5. Of the trials which adjusted for center using a method of analysis which requires a large number of events per center, 6% had less than 1 event per center-treatment combination, 25% fewer than 3, and 50% fewer than 5. Methods of analysis that allow for few events per center, such as random-effects models or generalized estimating equations (GEEs), were rarely used. Many multicenter trials contain few events per center. Adjustment for center using random-effects models or GEE with model-based (non-robust) standard errors may be beneficial in these scenarios. Copyright © 2015 Elsevier Inc. All rights reserved.

Note on an Identity Between Two Unbiased Variance Estimators for the Grand Mean in a Simple Random Effects Model.

Science.gov (United States)

Levin, Bruce; Leu, Cheng-Shiun

2013-01-01

We demonstrate the algebraic equivalence of two unbiased variance estimators for the sample grand mean in a random sample of subjects from an infinite population where subjects provide repeated observations following a homoscedastic random effects model.

Effective degrees of freedom of a random walk on a fractal

Science.gov (United States)

Balankin, Alexander S.

2015-12-01

We argue that a non-Markovian random walk on a fractal can be treated as a Markovian process in a fractional dimensional space with a suitable metric. This allows us to define the fractional dimensional space allied to the fractal as the ν -dimensional space Fν equipped with the metric induced by the fractal topology. The relation between the number of effective spatial degrees of freedom of walkers on the fractal (ν ) and fractal dimensionalities is deduced. The intrinsic time of random walk in Fν is inferred. The Laplacian operator in Fν is constructed. This allows us to map physical problems on fractals into the corresponding problems in Fν. In this way, essential features of physics on fractals are revealed. Particularly, subdiffusion on path-connected fractals is elucidated. The Coulomb potential of a point charge on a fractal embedded in the Euclidean space is derived. Intriguing attributes of some types of fractals are highlighted.

Random crystal field effects on the integer and half-integer mixed-spin system

Science.gov (United States)

Yigit, Ali; Albayrak, Erhan

2018-05-01

In this work, we have focused on the random crystal field effects on the phase diagrams of the mixed spin-1 and spin-5/2 Ising system obtained by utilizing the exact recursion relations (ERR) on the Bethe lattice (BL). The distribution function P(Di) = pδ [Di - D(1 + α) ] +(1 - p) δ [Di - D(1 - α) ] is used to randomize the crystal field.The phase diagrams are found to exhibit second- and first-order phase transitions depending on the values of α, D and p. It is also observed that the model displays tricritical point, isolated point, critical end point and three compensation temperatures for suitable values of the system parameters.

Effects of functional restoration versus 3 hours per week physical therapy: a randomized controlled study.

Science.gov (United States)

Jousset, Nathalie; Fanello, Serge; Bontoux, Luc; Dubus, Valérie; Billabert, Colette; Vielle, Bruno; Roquelaure, Yves; Penneau-Fontbonne, Dominique; Richard, Isabelle

2004-03-01

Randomized parallel-group comparative trial with a 6-month follow-up period. To compare, in chronic low back pain patients, the effectiveness of a functional restoration program, including intensive physical training, occupational therapy, and psychological support to an active individual therapy consisting of 3 hours physical therapy per week during 5 weeks. Controlled studies conducted in the United States showed a benefit of functional restoration in patients with low back pain, especially on return to work. Randomized Canadian and European trials had less favorable results. In France, there has been up to now no randomized study. Controlled studies suggested a positive effect of functional restoration programs. Eighty-six patients with low back pain were randomized to either the functional restoration (44 patients) or the active individual therapy (42 patients) program. One person in each group never started the program. Two patients did not complete the functional restoration program, and one was lost to follow-up at 6 months. The mean number of sick-leave days in the 2 previous years was 6 months. After adjustment on the variable "workplace enrolled in an ergonomic program", the mean number of sick-leave days was significantly lower in the functional restoration group. Physical criteria and treatment appreciation were also better. There was no significant difference in the intensity of pain, the quality of life and functional indexes, the psychological characteristics, the number of contacts with the medical system, and the drug intake. This study demonstrates the effectiveness of a functional restoration program on important outcome measures, such as sick leave, in a country that has a social system that protects people facing difficulties at work.

A randomized controlled trial of the effectiveness of multisystemic therapy in the Netherlands: post-treatment changes and moderator effects

NARCIS (Netherlands)

Asscher, J.J.; Deković, M.; Manders, W.A.; van der Laan, P.H.; Prins, P.J.M.

2013-01-01

Objective: In the present randomized controlled trial, the effectiveness of multisystemic therapy (MST) in The Netherlands was examined. Moderator tests were conducted for ethnicity, age and gender. Methods: The sample consisted of N = 256 adolescents, referred because of conduct problems, and

Effect of inter-crystal scatter on estimation methods for random coincidences and subsequent correction

International Nuclear Information System (INIS)

Torres-Espallardo, I; Spanoudaki, V; Ziegler, S I; Rafecas, M; McElroy, D P

2008-01-01

Random coincidences can contribute substantially to the background in positron emission tomography (PET). Several estimation methods are being used for correcting them. The goal of this study was to investigate the validity of techniques for random coincidence estimation, with various low-energy thresholds (LETs). Simulated singles list-mode data of the MADPET-II small animal PET scanner were used as input. The simulations have been performed using the GATE simulation toolkit. Several sources with different geometries have been employed. We evaluated the number of random events using three methods: delayed window (DW), singles rate (SR) and time histogram fitting (TH). Since the GATE simulations allow random and true coincidences to be distinguished, a comparison between the number of random coincidences estimated using the standard methods and the number obtained using GATE was performed. An overestimation in the number of random events was observed using the DW and SR methods. This overestimation decreases for LETs higher than 255 keV. It is additionally reduced when the single events which have undergone a Compton interaction in crystals before being detected are removed from the data. These two observations lead us to infer that the overestimation is due to inter-crystal scatter. The effect of this mismatch in the reconstructed images is important for quantification because it leads to an underestimation of activity. This was shown using a hot-cold-background source with 3.7 MBq total activity in the background region and a 1.59 MBq total activity in the hot region. For both 200 keV and 400 keV LET, an overestimation of random coincidences for the DW and SR methods was observed, resulting in approximately 1.5% or more (at 200 keV LET: 1.7% for DW and 7% for SR) and less than 1% (at 400 keV LET: both methods) underestimation of activity within the background region. In almost all cases, images obtained by compensating for random events in the reconstruction

Multilevel covariance regression with correlated random effects in the mean and variance structure.

Science.gov (United States)

Quintero, Adrian; Lesaffre, Emmanuel

2017-09-01

Multivariate regression methods generally assume a constant covariance matrix for the observations. In case a heteroscedastic model is needed, the parametric and nonparametric covariance regression approaches can be restrictive in the literature. We propose a multilevel regression model for the mean and covariance structure, including random intercepts in both components and allowing for correlation between them. The implied conditional covariance function can be different across clusters as a result of the random effect in the variance structure. In addition, allowing for correlation between the random intercepts in the mean and covariance makes the model convenient for skewedly distributed responses. Furthermore, it permits us to analyse directly the relation between the mean response level and the variability in each cluster. Parameter estimation is carried out via Gibbs sampling. We compare the performance of our model to other covariance modelling approaches in a simulation study. Finally, the proposed model is applied to the RN4CAST dataset to identify the variables that impact burnout of nurses in Belgium. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Mediation and spillover effects in group-randomized trials: a case study of the 4Rs educational intervention

Science.gov (United States)

VanderWeele, Tyler J.; Hong, Guanglei; Jones, Stephanie M.; Brown, Joshua L.

2013-01-01

Peer influence and social interactions can give rise to spillover effects in which the exposure of one individual may affect outcomes of other individuals. Even if the intervention under study occurs at the group or cluster level as in group-randomized trials, spillover effects can occur when the mediator of interest is measured at a lower level than the treatment. Evaluators who choose groups rather than individuals as experimental units in a randomized trial often anticipate that the desirable changes in targeted social behaviors will be reinforced through interference among individuals in a group exposed to the same treatment. In an empirical evaluation of the effect of a school-wide intervention on reducing individual students’ depressive symptoms, schools in matched pairs were randomly assigned to the 4Rs intervention or the control condition. Class quality was hypothesized as an important mediator assessed at the classroom level. We reason that the quality of one classroom may affect outcomes of children in another classroom because children interact not simply with their classmates but also with those from other classes in the hallways or on the playground. In investigating the role of class quality as a mediator, failure to account for such spillover effects of one classroom on the outcomes of children in other classrooms can potentially result in bias and problems with interpretation. Using a counterfactual conceptualization of direct, indirect and spillover effects, we provide a framework that can accommodate issues of mediation and spillover effects in group randomized trials. We show that the total effect can be decomposed into a natural direct effect, a within-classroom mediated effect and a spillover mediated effect. We give identification conditions for each of the causal effects of interest and provide results on the consequences of ignoring “interference” or “spillover effects” when they are in fact present. Our modeling approach

Effectiveness of preemptive lysine clonixinate in tooth extraction: A randomized controlled trial.

Directory of Open Access Journals (Sweden)

Pedro Aravena

2013-12-01

Full Text Available Aim: To evaluate the effectiveness of prophylaxis with single-dose analgesic clonixinate lysine (CL 125mg in patients undergoing tooth extraction. Methods: A double-blind randomized placebo-controlled trial. Were included in the study patients ASA I and II with dental extraction indication in the city of Valdivia, Chile in October 2012. Were randomly assigned in two groups: the treatment group received a doses of 125mg of CL fifteen minutes before the surgery, and a control group who received placebo. Both groups used a CL as a rescue analgesic. Using a survey, patients reported the degree of pain via a visual analog scale (VAS during the first day, at 24 and 48 hours after surgery. In addition, registered the number of CL capsules consumed as a ransom for 3 days after the surgery. We compared the analgesic effect observed in (VAS and the number of additional analgesic consumption between the two groups using t-test (p<0.05. Results: Fifty-four patients were operated and there was no statistically significant difference between the pain scores between the two groups. Premedication patients reported the use of equal number of rescue capsules comparing with the control group. Conclusion: CL analgesic prophylaxis proved no more effective in reducing pain after tooth extraction when comparing to the use of placebo in a postoperative doses.

Dynamic Output Feedback Control for Nonlinear Networked Control Systems with Random Packet Dropout and Random Delay

Directory of Open Access Journals (Sweden)

Shuiqing Yu

2013-01-01

Full Text Available This paper investigates the dynamic output feedback control for nonlinear networked control systems with both random packet dropout and random delay. Random packet dropout and random delay are modeled as two independent random variables. An observer-based dynamic output feedback controller is designed based upon the Lyapunov theory. The quantitative relationship of the dropout rate, transition probability matrix, and nonlinear level is derived by solving a set of linear matrix inequalities. Finally, an example is presented to illustrate the effectiveness of the proposed method.

Random matrices and random difference equations

International Nuclear Information System (INIS)

Uppuluri, V.R.R.

1975-01-01

Mathematical models leading to products of random matrices and random difference equations are discussed. A one-compartment model with random behavior is introduced, and it is shown how the average concentration in the discrete time model converges to the exponential function. This is of relevance to understanding how radioactivity gets trapped in bone structure in blood--bone systems. The ideas are then generalized to two-compartment models and mammillary systems, where products of random matrices appear in a natural way. The appearance of products of random matrices in applications in demography and control theory is considered. Then random sequences motivated from the following problems are studied: constant pulsing and random decay models, random pulsing and constant decay models, and random pulsing and random decay models

A Cluster Randomized Controlled Trial Testing the Effectiveness of Houvast: A Strengths-Based Intervention for Homeless Young Adults

Science.gov (United States)

Krabbenborg, Manon A. M.; Boersma, Sandra N.; van der Veld, William M.; van Hulst, Bente; Vollebergh, Wilma A. M.; Wolf, Judith R. L. M.

2017-01-01

Objective: To test the effectiveness of Houvast: a strengths-based intervention for homeless young adults. Method: A cluster randomized controlled trial was conducted with 10 Dutch shelter facilities randomly allocated to an intervention and a control group. Homeless young adults were interviewed when entering the facility and when care ended.…

Effect of aromatherapy on dental patient anxiety: A randomized controlled trial

Directory of Open Access Journals (Sweden)

M Venkataramana

2016-01-01

Full Text Available Introduction: Dental anxiety is a common and potentially distressing problem, both for the patients and for dental practitioners. It is considered to be the main barrier and affects the working lives of dental professional potentially compromising their performance. Aim: To know the effect of aromatherapy in the reduction of dental anxiety and to compare the anxiety levels of dental patients with the control group. Materials and Methods: A randomized controlled trial design was used. Of 40 dental clinics in Khammam town, 10 dental clinics were selected by simple random sampling method. A total of 100 patients attending the dental clinic for the first time were included in the study. Ambient odor of lavender was maintained with a candle warmer. A questionnaire comprising demographic information, smoking status, Modified dental anxiety scale (Humphries et al. in 1995, was given to the patients when they were waiting in the waiting room. Student's t-test and ANOVA test were used for data analysis. The level of significance was set at 0.05. Results: Considerable decrease in anxiety scores in 3 age groups was observed. A statistically significant (P = 0.002 decrease with age in mean anxiety score. A significant difference in anxiety scores of lavender group, a significant decrease of anxiety scores with an increase of age. Conclusion: Lavender decreased the current anxiety scores of patients effectively.

An effective group psychoeducational intervention for improving compliance with vaginal dilation: A randomized controlled trial

International Nuclear Information System (INIS)

Jeffries, Sherryl A.; Robinson, John W.; Craighead, Peter S.; Keats, Melanie R.

2006-01-01

Purpose: Although vaginal dilation is often recommended to minimize or prevent vaginal scarring after pelvic radiotherapy, compliance with this recommendation has historically been very low. Therefore, effective intervention strategies are needed to enhance compliance with vaginal dilation after radiotherapy for gynecologic cancer. Methods and Materials: This study was a randomized controlled clinical trial of a psychoeducational intervention specifically designed to increase compliance with vaginal dilation. The information-motivation-behavioral skills model of enhancing compliance with behavioral change was the basis for the intervention design. Forty-two sexually active women, 21 to 65 years of age, diagnosed with Stages Ic-III cervical or endometrial cancer, who received pelvic radiotherapy, were randomized to either the experimental psychoeducational group or the information-only control group. Assessment via questionnaire occurred before treatment and at 6-week, 6-month, 12-month, 18-month, and 24-month follow-up. Assessment via interview also occurred at 6-month, 12-month, 18-month, and 24-month follow-up. Results: The psychoeducational intervention was successful in increasing compliance with vaginal dilation. Conclusions: This study is the first randomized controlled study to demonstrate the effectiveness of an intervention in increasing compliance with the use of vaginal dilators

A Bayesian Analysis of a Random Effects Small Business Loan Credit Scoring Model

Directory of Open Access Journals (Sweden)

Patrick J. Farrell

2011-09-01

Full Text Available One of the most important aspects of credit scoring is constructing a model that has low misclassification rates and is also flexible enough to allow for random variation. It is also well known that, when there are a large number of highly correlated variables as is typical in studies involving questionnaire data, a method must be found to reduce the number of variables to those that have high predictive power. Here we propose a Bayesian multivariate logistic regression model with both fixed and random effects for small business loan credit scoring and a variable reduction method using Bayes factors. The method is illustrated on an interesting data set based on questionnaires sent to loan officers in Canadian banks and venture capital companies

A comparison of observation-level random effect and Beta-Binomial models for modelling overdispersion in Binomial data in ecology & evolution.

Science.gov (United States)

Harrison, Xavier A

2015-01-01

Overdispersion is a common feature of models of biological data, but researchers often fail to model the excess variation driving the overdispersion, resulting in biased parameter estimates and standard errors. Quantifying and modeling overdispersion when it is present is therefore critical for robust biological inference. One means to account for overdispersion is to add an observation-level random effect (OLRE) to a model, where each data point receives a unique level of a random effect that can absorb the extra-parametric variation in the data. Although some studies have investigated the utility of OLRE to model overdispersion in Poisson count data, studies doing so for Binomial proportion data are scarce. Here I use a simulation approach to investigate the ability of both OLRE models and Beta-Binomial models to recover unbiased parameter estimates in mixed effects models of Binomial data under various degrees of overdispersion. In addition, as ecologists often fit random intercept terms to models when the random effect sample size is low (model types under a range of random effect sample sizes when overdispersion is present. Simulation results revealed that the efficacy of OLRE depends on the process that generated the overdispersion; OLRE failed to cope with overdispersion generated from a Beta-Binomial mixture model, leading to biased slope and intercept estimates, but performed well for overdispersion generated by adding random noise to the linear predictor. Comparison of parameter estimates from an OLRE model with those from its corresponding Beta-Binomial model readily identified when OLRE were performing poorly due to disagreement between effect sizes, and this strategy should be employed whenever OLRE are used for Binomial data to assess their reliability. Beta-Binomial models performed well across all contexts, but showed a tendency to underestimate effect sizes when modelling non-Beta-Binomial data. Finally, both OLRE and Beta-Binomial models performed

Effect of a mobile app intervention on vegetable consumption in overweight adults: a randomized controlled trial.

Science.gov (United States)

Mummah, Sarah; Robinson, Thomas N; Mathur, Maya; Farzinkhou, Sarah; Sutton, Stephen; Gardner, Christopher D

2017-09-15

Mobile applications (apps) have been heralded as transformative tools to deliver behavioral health interventions at scale, but few have been tested in rigorous randomized controlled trials. We tested the effect of a mobile app to increase vegetable consumption among overweight adults attempting weight loss maintenance. Overweight adults (n=135) aged 18-50 years with BMI=28-40 kg/m 2 near Stanford, CA were recruited from an ongoing 12-month weight loss trial (parent trial) and randomly assigned to either the stand-alone, theory-based Vegethon mobile app (enabling goal setting, self-monitoring, and feedback and using "process motivators" including fun, surprise, choice, control, social comparison, and competition) or a wait-listed control condition. The primary outcome was daily vegetables servings, measured by an adapted Harvard food frequency questionnaire (FFQ) 8 weeks post-randomization. Daily vegetable servings from 24-hour dietary recalls, administered by trained, certified, and blinded interviewers 5 weeks post-randomization, was included as a secondary outcome. All analyses were conducted according to principles of intention-to-treat. Daily vegetable consumption was significantly greater in the intervention versus control condition for both measures (adjusted mean difference: 2.0 servings; 95% CI: 0.1, 3.8, p=0.04 for FFQ; and 1.0 servings; 95% CI: 0.2, 1.9; p=0.02 for 24-hour recalls). Baseline vegetable consumption was a significant moderator of intervention effects (p=0.002) in which effects increased as baseline consumption increased. These results demonstrate the efficacy of a mobile app to increase vegetable consumption among overweight adults. Theory-based mobile interventions may present a low-cost, scalable, and effective approach to improving dietary behaviors and preventing associated chronic diseases. ClinicalTrials.gov NCT01826591. Registered 27 March 2013.

A comparison of observation-level random effect and Beta-Binomial models for modelling overdispersion in Binomial data in ecology & evolution

Directory of Open Access Journals (Sweden)

Xavier A. Harrison

2015-07-01

Full Text Available Overdispersion is a common feature of models of biological data, but researchers often fail to model the excess variation driving the overdispersion, resulting in biased parameter estimates and standard errors. Quantifying and modeling overdispersion when it is present is therefore critical for robust biological inference. One means to account for overdispersion is to add an observation-level random effect (OLRE to a model, where each data point receives a unique level of a random effect that can absorb the extra-parametric variation in the data. Although some studies have investigated the utility of OLRE to model overdispersion in Poisson count data, studies doing so for Binomial proportion data are scarce. Here I use a simulation approach to investigate the ability of both OLRE models and Beta-Binomial models to recover unbiased parameter estimates in mixed effects models of Binomial data under various degrees of overdispersion. In addition, as ecologists often fit random intercept terms to models when the random effect sample size is low (<5 levels, I investigate the performance of both model types under a range of random effect sample sizes when overdispersion is present. Simulation results revealed that the efficacy of OLRE depends on the process that generated the overdispersion; OLRE failed to cope with overdispersion generated from a Beta-Binomial mixture model, leading to biased slope and intercept estimates, but performed well for overdispersion generated by adding random noise to the linear predictor. Comparison of parameter estimates from an OLRE model with those from its corresponding Beta-Binomial model readily identified when OLRE were performing poorly due to disagreement between effect sizes, and this strategy should be employed whenever OLRE are used for Binomial data to assess their reliability. Beta-Binomial models performed well across all contexts, but showed a tendency to underestimate effect sizes when modelling non

Randomized controlled trial of the effect of medical audit on AIDS prevention in general practice

DEFF Research Database (Denmark)

Sandbæk, Annelli

1999-01-01

OBJECTIVE: We aimed to evaluate the effect of a medical audit on AIDS prevention in general practice. METHODS: We conducted a prospective randomized controlled study performed as 'lagged intervention'. At the time of comparison, the intervention group had completed 6 months of audit including a p...... of such consultations initiated by the GPs. CONCLUSIONS: Medical audit had no observed effect on AIDS prevention in general practice. Udgivelsesdato: 1999-Oct......OBJECTIVE: We aimed to evaluate the effect of a medical audit on AIDS prevention in general practice. METHODS: We conducted a prospective randomized controlled study performed as 'lagged intervention'. At the time of comparison, the intervention group had completed 6 months of audit including....... One hundred and thirty-three GPs completed the project. The main outcome measures were the number of consultations involving AIDS prevention and the number of talks about AIDS initiated by the GP, and some elements of the content were registered on a chart. RESULTS: No statistically significant...

The effect of different types of music on patients' preoperative anxiety: A randomized controlled trial.

Science.gov (United States)

Uğraş, Gülay Altun; Yıldırım, Güven; Yüksel, Serpil; Öztürkçü, Yusuf; Kuzdere, Mustafa; Öztekin, Seher Deniz

2018-05-01

The purpose of this study was to determine effect of three different types of music on patients' preoperative anxiety. This randomized controlled trial included 180 patients who were randomly divided into four groups. While the control group didn't listen to music, the experimental groups respectively listened to natural sounds, Classical Turkish or Western Music for 30 min. The State Anxiety Inventory (STAI-S), systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR) and cortisol levels were checked. The post-music STAI-S, SBP, DBP, HR and cortisol levels of the patients in music groups were significantly lower than pre-music time. All types of music decreased STAI-S, SBP, and cortisol levels; additionally natural sounds reduced DBP; Classical Turkish Music also decreased DBP, and HR. All types of music had an effect on reducing patients' preoperative anxiety, and listening to Classical Turkish Music was particularly the most effective one. Copyright © 2018 Elsevier Ltd. All rights reserved.

Effect of Liraglutide on Ectopic Fat in Polycystic Ovary Syndrome: A Randomized Clinical Trial

DEFF Research Database (Denmark)

Frøssing, Signe; Nylander, Malin; Chabanova, Elizaveta

2018-01-01

Women with polycystic ovary syndrome (PCOS) were treated with the GLP-1 receptor agonist liraglutide to investigate the effect on liver fat content, visceral adipose tissue (VAT) and the prevalence of nonalcoholic fatty liver disease (NAFLD). In a double-blind, placebo-controlled, randomized clin...

Methods for synthesizing findings on moderation effects across multiple randomized trials.

Science.gov (United States)

Brown, C Hendricks; Sloboda, Zili; Faggiano, Fabrizio; Teasdale, Brent; Keller, Ferdinand; Burkhart, Gregor; Vigna-Taglianti, Federica; Howe, George; Masyn, Katherine; Wang, Wei; Muthén, Bengt; Stephens, Peggy; Grey, Scott; Perrino, Tatiana

2013-04-01

This paper presents new methods for synthesizing results from subgroup and moderation analyses across different randomized trials. We demonstrate that such a synthesis generally results in additional power to detect significant moderation findings above what one would find in a single trial. Three general methods for conducting synthesis analyses are discussed, with two methods, integrative data analysis and parallel analyses, sharing a large advantage over traditional methods available in meta-analysis. We present a broad class of analytic models to examine moderation effects across trials that can be used to assess their overall effect and explain sources of heterogeneity, and present ways to disentangle differences across trials due to individual differences, contextual level differences, intervention, and trial design.

Effectiveness of exercise at workplace in physical fitness: uncontrolled randomized study.

Science.gov (United States)

Grande, Antônio José; Silva, Valter; Parra, Sérgio Alencar

2014-01-01

To investigate the effectiveness of workplace exercise for employee health by means of health-related physical activity components. A randomized uncontrolled study with 20 workers was carried out during three months to evaluate a workplace exercise program. The selected outcomes were flexibility, body mass, fat percentage, lean mass, blood pressure, and heart rate. For statistical analysis, the paired t test and the intent-to-treat analysis were used. There was a significant increase in weight, fat percentage, blood pressure, and heart rate. However the clinical significance was 10% in the size of the effect. The changes verified in the outcomes analyzed were not significant; the variables are within normality ranges proposed by academic organizations.

Random walk on random walks

NARCIS (Netherlands)

Hilário, M.; Hollander, den W.Th.F.; Sidoravicius, V.; Soares dos Santos, R.; Teixeira, A.

2014-01-01

In this paper we study a random walk in a one-dimensional dynamic random environment consisting of a collection of independent particles performing simple symmetric random walks in a Poisson equilibrium with density ¿¿(0,8). At each step the random walk performs a nearest-neighbour jump, moving to

Effect of Ecuador's cash transfer program (Bono de Desarrollo Humano) on child development in infants and toddlers: a randomized effectiveness trial.

Science.gov (United States)

Fernald, Lia C H; Hidrobo, Melissa

2011-05-01

We examined the effects of Ecuador's Bono de Desarrollo Humano (BDH)--an unconditional cash transfer program that was rolled-out using a randomized design--on health and development outcomes in very young children. Communities that were randomly assigned to the treatment group began receiving the BDH in 2004 and those randomly assigned to the comparison group began receiving benefits two years later. Families enrolled in the BDH received a monthly cash stipend ($15USD) representing an approximate 6-10% increase in household income. Participants analyzed in this study are children aged 12-35 months from treatment (n = 797) and comparison (n = 399) communities in rural and urban Ecuador. Main outcomes measured were language skills (the Fundación MacArthur Inventorio del Desarollo de Habilidades Comunicativas-Breve), height-for-age z-score, and hemoglobin concentration. Results indicate that in rural areas, being randomized to receive the BDH in very early childhood led to significantly better performance on the number of words a child was saying, and on the probability that the child was combining two or more words. There were no significant effects on language development for children in urban areas and there were no effects on height-for-age z-score or hemoglobin concentration in rural or urban areas. A limited number of potential pathways with respect to cognitive/language stimulation, health behaviors, and parenting quality were also explored. Findings indicate that compared to children in comparison areas, rural children in treatment areas were more likely to have received vitamin A or iron supplementation and have been bought a toy in the past six months. This study provides evidence for significant benefits of an unconditional cash transfer program for language development in very young children in rural areas. Copyright © 2011 Elsevier Ltd. All rights reserved.

Random crystal field effect on the magnetic and hysteresis behaviors of a spin-1 cylindrical nanowire

Energy Technology Data Exchange (ETDEWEB)

Zaim, N.; Zaim, A., E-mail: ah_zaim@yahoo.fr; Kerouad, M., E-mail: kerouad@fs-umi.ac.ma

2017-02-15

In this work, the magnetic behavior of the cylindrical nanowire, consisting of a ferromagnetic core of spin-1 atoms surrounded by a ferromagnetic shell of spin-1 atoms is studied in the presence of a random crystal field interaction. Based on Metropolis algorithm, the Monte Carlo simulation has been used to investigate the effects of the concentration of the random crystal field p, the crystal field D and the shell exchange interaction J{sub s} on the phase diagrams and the hysteresis behavior of the system. Some characteristic behaviors have been found, such as the first and second-order phase transitions joined by tricritical point for appropriate values of the system parameters, triple and isolated critical points can be also found. Depending on the Hamiltonian parameters, single, double and para hysteresis regions are explicitly determined. - Highlights: • Phase diagrams of a ferromagnetic nanowire are examined by the Monte Carlo simulation. • Different types of the phase diagrams are obtained. • The effect of the random crystal field on the hysteresis loops is studied. • Single, double and para hysteresis regions are explicitly determined.

Effects of Aerobic Exercise on Overweight Children's Cognitive Functioning: A Randomized Controlled Trial

Science.gov (United States)

Davis, Catherine L.; Tomporowski, Phillip D.; Boyle, Colleen A.; Waller, Jennifer L.; Miller, Patricia H.; Naglieri, Jack A.; Gregoski, Mathew

2007-01-01

The study tested the effect of aerobic exercise training on executive function in overweight children. Ninety-four sedentary, overweight but otherwise healthy children (mean age = 9.2 years, body mass index [greater than or equal to] 85th percentile) were randomized to a low-dose (20 min/day exercise), high-dose (40 min/day exercise), or control…

Linearization effect in multifractal analysis: Insights from the Random Energy Model

Science.gov (United States)

Angeletti, Florian; Mézard, Marc; Bertin, Eric; Abry, Patrice

2011-08-01

The analysis of the linearization effect in multifractal analysis, and hence of the estimation of moments for multifractal processes, is revisited borrowing concepts from the statistical physics of disordered systems, notably from the analysis of the so-called Random Energy Model. Considering a standard multifractal process (compound Poisson motion), chosen as a simple representative example, we show the following: (i) the existence of a critical order q∗ beyond which moments, though finite, cannot be estimated through empirical averages, irrespective of the sample size of the observation; (ii) multifractal exponents necessarily behave linearly in q, for q>q∗. Tailoring the analysis conducted for the Random Energy Model to that of Compound Poisson motion, we provide explicative and quantitative predictions for the values of q∗ and for the slope controlling the linear behavior of the multifractal exponents. These quantities are shown to be related only to the definition of the multifractal process and not to depend on the sample size of the observation. Monte Carlo simulations, conducted over a large number of large sample size realizations of compound Poisson motion, comfort and extend these analyses.

Effect of texture randomization on the slip and interfacial robustness in turbulent flows over superhydrophobic surfaces

Science.gov (United States)

Seo, Jongmin; Mani, Ali

2018-04-01

Superhydrophobic surfaces demonstrate promising potential for skin friction reduction in naval and hydrodynamic applications. Recent developments of superhydrophobic surfaces aiming for scalable applications use random distribution of roughness, such as spray coating and etched process. However, most previous analyses of the interaction between flows and superhydrophobic surfaces studied periodic geometries that are economically feasible only in laboratory-scale experiments. In order to assess the drag reduction effectiveness as well as interfacial robustness of superhydrophobic surfaces with randomly distributed textures, we conduct direct numerical simulations of turbulent flows over randomly patterned interfaces considering a range of texture widths w+≈4 -26 , and solid fractions ϕs=11 %-25 % . Slip and no-slip boundary conditions are implemented in a pattern, modeling the presence of gas-liquid interfaces and solid elements. Our results indicate that slip of randomly distributed textures under turbulent flows is about 30 % less than those of surfaces with aligned features of the same size. In the small texture size limit w+≈4 , the slip length of the randomly distributed textures in turbulent flows is well described by a previously introduced Stokes flow solution of randomly distributed shear-free holes. By comparing DNS results for patterned slip and no-slip boundary against the corresponding homogenized slip length boundary conditions, we show that turbulent flows over randomly distributed posts can be represented by an isotropic slip length in streamwise and spanwise direction. The average pressure fluctuation on a gas pocket is similar to that of the aligned features with the same texture size and gas fraction, but the maximum interface deformation at the leading edge of the roughness element is about twice as large when the textures are randomly distributed. The presented analyses provide insights on implications of texture randomness on drag

The effectiveness of participatory ergonomics to prevent low-back and neck pain - results of a cluster randomized controlled trial

NARCIS (Netherlands)

Driessen, M.T.; Proper, K.I.; Anema, J.R.; Knol, D.L.; Bongers, P.M.; Beek, A.J. van der

2011-01-01

Objective The aim of this randomized controlled trial (RCT) was to investigate the effectiveness of the Stay@ Work participatory ergonomics (PE) program to prevent low-back and neck pain. Methods A total of 37 departments were randomly allocated to either the intervention (PE) or control group (no

Strong coupling electrostatics for randomly charged surfaces: antifragility and effective interactions.

Science.gov (United States)

Ghodrat, Malihe; Naji, Ali; Komaie-Moghaddam, Haniyeh; Podgornik, Rudolf

2015-05-07

We study the effective interaction mediated by strongly coupled Coulomb fluids between dielectric surfaces carrying quenched, random monopolar charges with equal mean and variance, both when the Coulomb fluid consists only of mobile multivalent counterions and when it consists of an asymmetric ionic mixture containing multivalent and monovalent (salt) ions in equilibrium with an aqueous bulk reservoir. We analyze the consequences that follow from the interplay between surface charge disorder, dielectric and salt image effects, and the strong electrostatic coupling that results from multivalent counterions on the distribution of these ions and the effective interaction pressure they mediate between the surfaces. In a dielectrically homogeneous system, we show that the multivalent counterions are attracted towards the surfaces with a singular, disorder-induced potential that diverges logarithmically on approach to the surfaces, creating a singular but integrable counterion density profile that exhibits an algebraic divergence at the surfaces with an exponent that depends on the surface charge (disorder) variance. This effect drives the system towards a state of lower thermal 'disorder', one that can be described by a renormalized temperature, exhibiting thus a remarkable antifragility. In the presence of an interfacial dielectric discontinuity, the singular behavior of counterion density at the surfaces is removed but multivalent counterions are still accumulated much more strongly close to randomly charged surfaces as compared with uniformly charged ones. The interaction pressure acting on the surfaces displays in general a highly non-monotonic behavior as a function of the inter-surface separation with a prominent regime of attraction at small to intermediate separations. This attraction is caused directly by the combined effects from charge disorder and strong coupling electrostatics of multivalent counterions, which dominate the surface-surface repulsion due to

The effectiveness of xylitol in a school-based cluster-randomized clinical trial.

Science.gov (United States)

Lee, Wonik; Spiekerman, Charles; Heima, Masahiro; Eggertsson, Hafsteinn; Ferretti, Gerald; Milgrom, Peter; Nelson, Suchitra

2015-01-01

The purpose of this double-blind, cluster-randomized clinical trial was to examine the effects of xylitol gummy bear snacks on dental caries progression in primary and permanent teeth of inner-city school children. A total of 562 children aged 5-6 years were recruited from five elementary schools in East Cleveland, Ohio. Children were randomized by classroom to receive xylitol (7.8 g/day) or placebo (inulin fiber 20 g/day) gummy bears. Gummy bears were given three times per day for the 9-month kindergarten year within a supervised school environment. Children in both groups also received oral health education, toothbrush and fluoridated toothpaste, topical fluoride varnish treatment and dental sealants. The numbers of new decayed, missing, and filled surfaces for primary teeth (dmfs) and permanent teeth (DMFS) from baseline to the middle of 2nd grade (exit exam) were compared between the treatment (xylitol/placebo) groups using an optimally-weighted permutation test for cluster-randomized data. The mean new d(3-6)mfs at the exit exam was 5.0 ± 7.6 and 4.0 ± 6.5 for the xylitol and placebo group, respectively. Similarly, the mean new D(3-6)MFS was 0.38 ± 0.88 and 0.48 ± 1.39 for the xylitol and placebo group, respectively. The adjusted mean difference between the two groups was not statistically significant: new d(3-6)mfs: mean 0.4, 95% CI -0.25, 0.8), and new D(3-6)MFS: mean 0.16, 95% CI -0.16, 0.43. Xylitol consumption did not have additional benefit beyond other preventive measures. Caries progression in the permanent teeth of both groups was minimal, suggesting that other simultaneous prevention modalities may have masked the possible beneficial effects of xylitol in this trial. © 2014 S. Karger AG, Basel.

SU-G-TeP1-12: Random Repainting as Mitigation for Scanned Ion Beam Interplay Effects

Energy Technology Data Exchange (ETDEWEB)

Bach, M; Wulff, J [Varian Medical Systems Particle Therapy GmbH, Troisdorf, NRW (Germany)

2016-06-15

Purpose: Interference of dose application in scanned beam particle therapy and organ motion may lead to interplay effects with distorted dose to target volumes. Interplay effects depend on the speed and direction of the scanning beam, leading to fringed field edges (scanning parallel to organ motion direction) or over- and under-dosed regions (both directions are orthogonal). Current repainting methods can mitigate interplay effects, but are susceptible to artefacts when only a limited number of repaints are applied. In this study a random layered-repainting strategy was investigated. Methods: Mono-energetic proton beams were irradiated to a 10 ×10 cm{sup 2} scanned field at a Varian ProBeam facility. Applied dose was measured with a 2D amorphous silicon detector mounted on a motion platform (CIRS dynamic platform). Motion was considered with different cycles, directions and translations up to ±8 mm. Dose distributions were measured for a static case, regular repainting (repeated meander-like path) and random repainting. Latter was realized by randomly distributing single spot locations during irradiation for a given number of repaints. Efficiency of repainting was analyzed by comparison to the static case. A simulation tool based on treatment logs and motion information was developed to compare measurement results to expected dose distributions. Results: Regular repainting could reduce motion artefacts, but dose distortion was strongly dependent on motion direction. Random repainting with same number of repaints (N=4) showed superior results, independent of target movement direction, while introducing slight penalty on delivery times, caused by an increase of overall scanning travel distance. The simulation tool showed good agreement to measured results. Conclusion: The results demonstrate significant improvement in terms of dose conformity when layered repainting is applied in a randomized fashion. This allows for reduced target margins during treatment

SU-G-TeP1-12: Random Repainting as Mitigation for Scanned Ion Beam Interplay Effects

International Nuclear Information System (INIS)

Bach, M; Wulff, J

2016-01-01

Purpose: Interference of dose application in scanned beam particle therapy and organ motion may lead to interplay effects with distorted dose to target volumes. Interplay effects depend on the speed and direction of the scanning beam, leading to fringed field edges (scanning parallel to organ motion direction) or over- and under-dosed regions (both directions are orthogonal). Current repainting methods can mitigate interplay effects, but are susceptible to artefacts when only a limited number of repaints are applied. In this study a random layered-repainting strategy was investigated. Methods: Mono-energetic proton beams were irradiated to a 10 ×10 cm"2 scanned field at a Varian ProBeam facility. Applied dose was measured with a 2D amorphous silicon detector mounted on a motion platform (CIRS dynamic platform). Motion was considered with different cycles, directions and translations up to ±8 mm. Dose distributions were measured for a static case, regular repainting (repeated meander-like path) and random repainting. Latter was realized by randomly distributing single spot locations during irradiation for a given number of repaints. Efficiency of repainting was analyzed by comparison to the static case. A simulation tool based on treatment logs and motion information was developed to compare measurement results to expected dose distributions. Results: Regular repainting could reduce motion artefacts, but dose distortion was strongly dependent on motion direction. Random repainting with same number of repaints (N=4) showed superior results, independent of target movement direction, while introducing slight penalty on delivery times, caused by an increase of overall scanning travel distance. The simulation tool showed good agreement to measured results. Conclusion: The results demonstrate significant improvement in terms of dose conformity when layered repainting is applied in a randomized fashion. This allows for reduced target margins during treatment planning and

Improving satellite-based PM2.5 estimates in China using Gaussian processes modeling in a Bayesian hierarchical setting.

Science.gov (United States)

Yu, Wenxi; Liu, Yang; Ma, Zongwei; Bi, Jun

2017-08-01

Using satellite-based aerosol optical depth (AOD) measurements and statistical models to estimate ground-level PM 2.5 is a promising way to fill the areas that are not covered by ground PM 2.5 monitors. The statistical models used in previous studies are primarily Linear Mixed Effects (LME) and Geographically Weighted Regression (GWR) models. In this study, we developed a new regression model between PM 2.5 and AOD using Gaussian processes in a Bayesian hierarchical setting. Gaussian processes model the stochastic nature of the spatial random effects, where the mean surface and the covariance function is specified. The spatial stochastic process is incorporated under the Bayesian hierarchical framework to explain the variation of PM 2.5 concentrations together with other factors, such as AOD, spatial and non-spatial random effects. We evaluate the results of our model and compare them with those of other, conventional statistical models (GWR and LME) by within-sample model fitting and out-of-sample validation (cross validation, CV). The results show that our model possesses a CV result (R 2  = 0.81) that reflects higher accuracy than that of GWR and LME (0.74 and 0.48, respectively). Our results indicate that Gaussian process models have the potential to improve the accuracy of satellite-based PM 2.5 estimates.

Effect of Pentoxifylline on Microalbuminuria in Diabetic Patients: A Randomized Controlled Trial

Directory of Open Access Journals (Sweden)

Shahrzad Shahidi

2015-01-01

Full Text Available Background. Pentoxifylline is a nonspecific phosphodiesterase inhibitor with anti-inflammatory properties. Human studies have proved its antiproteinuric effect in patients with glomerular diseases, but this study was designed to assess the effects of add-on pentoxifylline to available treatment on reduction of microalbuminuria in diabetic patients without glomerular diseases. Methods. In a double-blind placebo-controlled, randomized study we evaluated the influence of pentoxifylline on microalbuminuria in type 2 diabetic patients. 40 diabetic patients with estimated glomerular filtration rate (eGFR of more than 60 mL/min/1.73 m2 in eight weeks and microalbuminuria were randomized to two groups which will receive pentoxifylline 1200 mg/day or placebo added to regular medications for 6 months. albuminuria; eGFR was evaluated at three- and six-month follow-up period. Results. Baseline characteristics were similar between the two groups. At six months, the mean estimated GFR and albuminuria were not different between two groups at 3- and 6-month follow-up. Trend of albumin to creatinine ratio, systolic and diastolic blood pressure, and eGFR in both groups were decreased, but no significant differences were noted between two groups (P value > 0.05. Conclusion. Pentoxifylline has not a significant additive antimicroalbuminuric effect compared with placebo in patients with type 2 diabetes with early stage of kidney disease; however, further clinical investigations are necessary to be done.

Randomized Controlled Trial of Social Media: Effect of Increased Intensity of the Intervention.

Science.gov (United States)

Fox, Caroline S; Gurary, Ellen B; Ryan, John; Bonaca, Marc; Barry, Karen; Loscalzo, Joseph; Massaro, Joseph

2016-04-27

A prior randomized controlled trial of social media exposure at Circulation determined that social media did not increase 30-day page views. Whether insufficient social media intensity contributed to these results is uncertain. Original article manuscripts were randomized to social media exposure compared with no social media exposure (control) at Circulation beginning in January 2015. Social media exposure consisted of Facebook and Twitter posts on the journal's accounts. To increase social media intensity, a larger base of followers was built using advertising and organic growth, and posts were presented in triplicate and boosted on Facebook and retweeted on Twitter. The primary outcome was 30-day page views. Stopping rules were established at the point that 50% of the manuscripts were randomized and had 30-day follow-up to compare groups on 30-day page views. The trial was stopped for futility on September 26, 2015. Overall, 74 manuscripts were randomized to receive social media exposure, and 78 manuscripts were randomized to the control arm. The intervention and control arms were similar based on article type (P=0.85), geographic location of the corresponding author (P=0.33), and whether the manuscript had an editorial (P=0.80). Median number of 30-day page views was 499.5 in the social media arm and 450.5 in the control arm; there was no evidence of a treatment effect (P=0.38). There were no statistically significant interactions of treatment by manuscript type (P=0.86), by corresponding author (P=0.35), by trimester of publication date (P=0.34), or by editorial status (P=0.79). A more intensive social media strategy did not result in increased 30-day page views of original research. © 2016 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

Causal Effects of Single-Sex Schools on College Entrance Exams and College Attendance: Random Assignment in Seoul High Schools

OpenAIRE

Park, Hyunjoon; Behrman, Jere R.; Choi, Jaesung

2013-01-01

Despite the voluminous literature on the potentials of single-sex schools, there is no consensus on the effects of single-sex schools because of student selection of school types. We exploit a unique feature of schooling in Seoul—the random assignment of students into single-sex versus coeducational high schools—to assess causal effects of single-sex schools on college entrance exam scores and college attendance. Our validation of the random assignment shows comparable socioeconomic backgroun...

Relative Cost-Effectiveness of Treatments for Adolescent Depression: 36-Week Results from the TADS Randomized Trial

Science.gov (United States)

Domino, Marisa Elena; Foster, E. Michael; Vitiello, Benedetto; Kratochvil, Christopher J.; Burns, Barbara J.; Silva, Susan G.; Reinecke, Mark A.; March, John S.

2009-01-01

Randomized controlled trials that involve 327 participants aged 12 to 18 who were diagnosed with major depression were given either fluoxetine alone, cognitive-behavioral therapy, or a combination of both. Cost-effectiveness acceptability curves suggest that combination treatment is highly likely to be the most cost-effective treatment than…

Effect of probiotic chewing tablets on early childhood caries--a randomized controlled trial

DEFF Research Database (Denmark)

Hedayati-Hajikand, Trifa; Lundberg, Ulrika; Eldh, Catarina

2015-01-01

BACKGROUND: To evaluate the effect of probiotic chewing tablets on early childhood caries development in preschool children living in a low socioeconomic multicultural area. METHODS: The investigation employed a randomized double-blind placebo-controlled design. The study group consisted of 138...... healthy 2-3-year-old children that were consecutively recruited after informed parental consent. After enrollment, they were randomized to a test or a placebo group. The parents of the test group were instructed to give their child one chewing tablet per day containing three strains of live probiotic...... childhood caries development could be reduced through administration of these probiotic chewing tablets as adjunct to daily use of fluoride toothpaste in preschool children. Further studies on a possible dose-response relationship seem justified TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01720771...

Effects of exercise and diet in nonobese asthma patients - a randomized controlled trial

DEFF Research Database (Denmark)

Tønnesen, Louise Lindhardt; Meteran, Howraman; Hostrup, Morten

2018-01-01

BACKGROUND: Behavioral interventions focusing on exercise and healthy diet improve asthma control in obese patients with asthma, but whether these interventions can lead to improvements in nonobese patients remains unclear. OBJECTIVES: In a randomized, controlled parallel-group design, we studied...... the effects of an 8-week intervention of either exercise (high-intensity interval training), diet (high protein/low glycemic index), or a combination of the 2, on asthma control and clinical outcomes in nonobese patients with asthma. METHODS: Nonobese adult patients with asthma (n = 149) were randomized to 1...... of 4 groups: an exercise group, a diet group, an exercise + diet group, or a control group. Outcomes included Asthma Control Questionnaire (ACQ) score, asthma-related quality-of-life (Asthma-Related Quality-of-Life Questionnaire [AQLQ]) score, inflammatory cell counts in induced sputum, FEV1...

Melatonin for Atypical Antipsychotic-Induced Metabolic Adverse Effects: A Meta-Analysis of Randomized Controlled Trials

Directory of Open Access Journals (Sweden)

Ashwin Kamath

2018-01-01

Full Text Available The objective of our study was to determine the effect of melatonin administration on atypical antipsychotic-induced metabolic adverse effects in patients with psychiatric disorders. A systematic search was performed in PUBMED, Cochrane Library, Scopus, Web of Science, and EBSCOhost electronic databases. Randomized controlled trials studying the effect of melatonin on antipsychotic-induced metabolic adverse effects were identified and subjected to meta-analysis. Four studies were included in the meta-analysis, including 57 patients on melatonin and 61 patients on placebo. Melatonin produced a significant decrease in the diastolic blood pressure compared with placebo (mean difference = −4.44 [95% CI, −7.00 to −1.88]; p=0.0007; I2 = 13%, but not the systolic blood pressure (mean difference = −4.23 [95% CI, −8.11 to −0.36]; p=0.03; I2 = 0%. Although a decrease in the body mass index was seen in the melatonin group, the difference was not significant in the random-effects analysis model. To conclude, in patients on atypical antipsychotics, melatonin at a dose of up to 5 mg/day for a treatment duration of up to 12 weeks attenuated the rise in diastolic blood pressure compared with placebo but had no significant effects on other metabolic parameters.

Melatonin for Atypical Antipsychotic-Induced Metabolic Adverse Effects: A Meta-Analysis of Randomized Controlled Trials.

Science.gov (United States)

Kamath, Ashwin; Rather, Zahoor Ahmad

2018-01-01

The objective of our study was to determine the effect of melatonin administration on atypical antipsychotic-induced metabolic adverse effects in patients with psychiatric disorders. A systematic search was performed in PUBMED, Cochrane Library, Scopus, Web of Science, and EBSCOhost electronic databases. Randomized controlled trials studying the effect of melatonin on antipsychotic-induced metabolic adverse effects were identified and subjected to meta-analysis. Four studies were included in the meta-analysis, including 57 patients on melatonin and 61 patients on placebo. Melatonin produced a significant decrease in the diastolic blood pressure compared with placebo (mean difference = -4.44 [95% CI, -7.00 to -1.88]; p = 0.0007; I 2 = 13%), but not the systolic blood pressure (mean difference = -4.23 [95% CI, -8.11 to -0.36]; p = 0.03; I 2 = 0%). Although a decrease in the body mass index was seen in the melatonin group, the difference was not significant in the random-effects analysis model. To conclude, in patients on atypical antipsychotics, melatonin at a dose of up to 5 mg/day for a treatment duration of up to 12 weeks attenuated the rise in diastolic blood pressure compared with placebo but had no significant effects on other metabolic parameters.

Components of effective randomized controlled trials of hydrotherapy programs for fibromyalgia syndrome: A systematic review

Directory of Open Access Journals (Sweden)

Luke Perraton

2009-11-01

Full Text Available Luke Perraton, Zuzana Machotka, Saravana KumarInternational Centre for Allied Health Evidence, University of South Australia, Adelaide, South Australia, AustraliaAim: Previous systematic reviews have found hydrotherapy to be an effective management strategy for fibromyalgia syndrome (FMS. The aim of this systematic review was to summarize the components of hydrotherapy programs used in randomized controlled trials.Method: A systematic review of randomized controlled trials was conducted. Only trials that have reported significant FMS-related outcomes were included. Data relating to the components of hydrotherapy programs (exercise type, duration, frequency and intensity, environmental factors, and service delivery were analyzed.Results: Eleven randomized controlled trials were included in this review. Overall, the quality of trials was good. Aerobic exercise featured in all 11 trials and the majority of hydrotherapy programs included either a strengthening or flexibility component. Great variability was noted in both the environmental components of hydrotherapy programs and service delivery.Conclusions: Aerobic exercise, warm up and cool-down periods and relaxation exercises are common features of hydrotherapy programs that report significant FMS-related outcomes. Treatment duration of 60 minutes, frequency of three sessions per week and an intensity equivalent to 60%–80% maximum heart rate were the most commonly reported exercise components. Exercise appears to be the most important component of an effective hydrotherapy program for FMS, particularly when considering mental health-related outcomes.Keywords: hydrotherapy, fibromyalgia syndrome, exercise, effective, components

Effects of the randomly distributed magnetic field on the phase diagrams of the Ising Nanowire II: Continuous distributions

International Nuclear Information System (INIS)

Akıncı, Ümit

2012-01-01

The effect of the random magnetic field distribution on the phase diagrams and ground state magnetizations of the Ising nanowire has been investigated with effective field theory with correlations. Gaussian distribution has been chosen as a random magnetic field distribution. The variation of the phase diagrams with that distribution parameters has been obtained and some interesting results have been found such as disappearance of the reentrant behavior and first order transitions which appear in the case of discrete distributions. Also for single and double Gaussian distributions, ground state magnetizations for different distribution parameters have been determined which can be regarded as separate partially ordered phases of the system. - Highlights: ► We give the phase diagrams of the Ising nanowire under the continuous randomly distributed magnetic field. ► Ground state magnetization values obtained. ► Different partially ordered phases observed.

The effectiveness of propolis on gingivitis: a randomized controlled trial.

Science.gov (United States)

Bretz, Walter A; Paulino, Niraldo; Nör, Jacques E; Moreira, Alexandre

2014-12-01

A randomized, double-blind, controlled clinical trial was conducted to evaluate the effectiveness of a propolis rinse on induced gingivitis by using the co-twin study design. Twenty-one twin pairs (n=42) were enrolled in a gingivitis study with oral hygiene promotion (14 days) and gingivitis induction (21 days). During the gingivitis induction phase, one member of the twin pair was randomly assigned to a 2% typified propolis rinse, and the other was assigned a color-matched 0.05% sodium fluoride plus 0.05% cetylpyridinium chloride rinse (positive control). Patients rinsed twice daily with 20 mL for 30 seconds for 21 days. Gingivitis was measured on days -14 (baseline), 0 (after hygiene phase), and 21 (after no-hygiene phase) by using the Papillary Bleeding Score (PBS) and by standard digital imaging of the gum tissues (G-parameter). The 38 persons who completed the study (age 13-22 years) were well balanced according to PBS at baseline and G-parameter after the initial hygiene phase. After 21 days without oral hygiene, the propolis rinse and positive control rinse groups did not differ significantly for average PBS measurements or G-parameter. Use of a 2% typified propolis rinse was equivalent to a positive control rinse during a 21-day no-hygiene period.

Random coil chemical shift for intrinsically disordered proteins

DEFF Research Database (Denmark)

Kjærgaard, Magnus; Brander, Søren; Poulsen, Flemming Martin

2011-01-01

. Temperature has a non-negligible effect on the (13)C random coil chemical shifts, so temperature coefficients are reported for the random coil chemical shifts to allow extrapolation to other temperatures. The pH dependence of the histidine random coil chemical shifts is investigated in a titration series......, which allows the accurate random coil chemical shifts to be obtained at any pH. By correcting the random coil chemical shifts for the effects of temperature and pH, systematic biases of the secondary chemical shifts are minimized, which will improve the reliability of detection of transient secondary...

Psychosocial effects of workplace physical exercise among workers with chronic pain:Randomized controlled trial

OpenAIRE

Andersen, Lars L.; Persson, Roger; Jakobsen, Markus D.; Sundstrup, Emil

2017-01-01

Abstract While workplace physical exercise can help manage musculoskeletal disorders, less is known about psychosocial effects of such interventions. This aim of this study was to investigate the effect of workplace physical exercise on psychosocial factors among workers with chronic musculoskeletal pain. The trial design was a 2-armed parallel-group randomized controlled trial with allocation concealment. A total of 66 slaughterhouse workers (51 men and 15 women, mean age 45 years [standard ...

The effect of COPD severity and study duration on exacerbation outcome in randomized controlled trials

NARCIS (Netherlands)

Eriksson, Goran; Calverley, Peter M.; Jenkins, Christine R.; Anzueto, Antonio R.; Make, Barry J.; Lindberg, Magnus; Fageras, Malin; Postma, Dirkje S.

2017-01-01

Background: When discontinuation in COPD randomized controlled trials (RCTs) is unevenly distributed between treatments (differential dropout), the capacity to demonstrate treatment effects may be reduced. We investigated the impact of the time of differential dropout on exacerbation outcomes in

Components of effective randomized controlled trials of hydrotherapy programs for fibromyalgia syndrome: A systematic review.

Science.gov (United States)

Perraton, Luke; Machotka, Zuzana; Kumar, Saravana

2009-11-30

Previous systematic reviews have found hydrotherapy to be an effective management strategy for fibromyalgia syndrome (FMS). The aim of this systematic review was to summarize the components of hydrotherapy programs used in randomized controlled trials. A systematic review of randomized controlled trials was conducted. Only trials that have reported significant FMS-related outcomes were included. Data relating to the components of hydrotherapy programs (exercise type, duration, frequency and intensity, environmental factors, and service delivery) were analyzed. Eleven randomized controlled trials were included in this review. Overall, the quality of trials was good. Aerobic exercise featured in all 11 trials and the majority of hydrotherapy programs included either a strengthening or flexibility component. Great variability was noted in both the environmental components of hydrotherapy programs and service delivery. Aerobic exercise, warm up and cool-down periods and relaxation exercises are common features of hydrotherapy programs that report significant FMS-related outcomes. Treatment duration of 60 minutes, frequency of three sessions per week and an intensity equivalent to 60%-80% maximum heart rate were the most commonly reported exercise components. Exercise appears to be the most important component of an effective hydrotherapy program for FMS, particularly when considering mental health-related outcomes.

Methods for Synthesizing Findings on Moderation Effects Across Multiple Randomized Trials

Science.gov (United States)

Brown, C Hendricks; Sloboda, Zili; Faggiano, Fabrizio; Teasdale, Brent; Keller, Ferdinand; Burkhart, Gregor; Vigna-Taglianti, Federica; Howe, George; Masyn, Katherine; Wang, Wei; Muthén, Bengt; Stephens, Peggy; Grey, Scott; Perrino, Tatiana

2011-01-01

This paper presents new methods for synthesizing results from subgroup and moderation analyses across different randomized trials. We demonstrate that such a synthesis generally results in additional power to detect significant moderation findings above what one would find in a single trial. Three general methods for conducting synthesis analyses are discussed, with two methods, integrative data analysis, and parallel analyses, sharing a large advantage over traditional methods available in meta-analysis. We present a broad class of analytic models to examine moderation effects across trials that can be used to assess their overall effect and explain sources of heterogeneity, and present ways to disentangle differences across trials due to individual differences, contextual level differences, intervention, and trial design. PMID:21360061

Intra-Amygdala ZIP Injections Impair the Memory of Learned Active Avoidance Responses and Attenuate Conditioned Taste-Aversion Acquisition in Rats

Science.gov (United States)

Gamiz, Fernando; Gallo, Milagros

2011-01-01

We have investigated the effect of protein kinase Mzeta (PKM[zeta]) inhibition in the basolateral amygdala (BLA) upon the retention of a nonspatial learned active avoidance response and conditioned taste-aversion (CTA) acquisition in rats. ZIP (10 nmol/[mu]L) injected into the BLA 24 h after training impaired retention of a learned…

Effect of disorder correlation in random mers

International Nuclear Information System (INIS)

Brezini, A.; Sebbani, M.; Depollier, C.; Belbachir, M.

1995-12-01

A widely held view in solid-state physics is that disorder precludes the presence of long-range transport in one-dimension. Recently a series of models has been proposed that do not conform to this view such as the well known Random Dimer Model (RDM). In the following paper, we must present a generalization of the RDM. In particular, the nature of the eigenstates of a non-interacting electron is investigated by means of a popular one-dimensional Kronig-Penney Hamiltonian in which n-mers have been placed at random on a regular lattice. Mainly in each allowed energy band of the spectrum, it is found that n-mers exhibits n - 1 resonances associated to extended states. Moreover these resonances appear to be narrower if the potential is attractive against repulsive, i.e. constituted of wells instead barriers, which discriminates the ability in localizing the eigenstates. Attention has been paid to the energy transition as one approaches the two resonances of the random trimer within the first allowed band. The transition exhibits a smooth behaviour for the lower energy when compared to the higher one with respect to the first resonance and shows quite a similar behaviour for both sides close to the second resonance. The discrepancy is attributed to the typical nature of the eigenstates for each resonance. Correspondingly, the wave functions associated to the first resonance are not like Bloch-waves while for the second one they look like the crystal wave functions displaying only minor distortions. (author). 44 refs, 6 figs

Effectivity of artrihpi irrigation for diabetic ulcer healing: A randomized controlled trial

Science.gov (United States)

Gayatri, Dewi; Asmorohadi, Aries; Dahlia, Debie

2018-02-01

The healing process of diabetic ulcer is often impeded by inflammation, infection, and decreased immune state. High pressure irrigation (10-15 psi) may be used to control the infection level. This research was designed to identify the effectiveness of artrihpi irrigation device towards diabetic ulcers in public hospitals in the Central Java. This research is a randomized control trial with cross over design. Sixty four subjects were selected using block randomization technique, and were divided into control and intervention group. The intervention was given in 6 days along with wound healing evaluation in every 3 days. The results demonstrated that there was a significant difference decrease scoring healing after treatment, even though the difference scoring healing between both groups was not statistically significant. However, it means difference was found that in the intervention artrihpi the wound healing was better than the spuit. These results illustrates the artrihpi may be solution of using high pressure irrigation to help healing process diabetic ulcers.

Effect of Metformin on Plasma Fibrinogen Concentrations: A Systematic Review and Meta-Analysis of Randomized Placebo-Controlled Trials.

Science.gov (United States)

Simental-Mendia, Luis E; Pirro, Matteo; Atkin, Stephen L; Banach, Maciej; Mikhailidis, Dimitri P; Sahebkar, Amirhossein

2018-01-01

Fibrinogen is a key mediator of thrombosis and it has been implicated in the pathogenesis of atherosclerosis. Because metformin has shown a potential protective effect on different atherothrombotic risk factors, we assessed in this meta-analysis its effect on plasma fibrinogen concentrations. A systematic review and meta-analysis was carried out to identify randomized placebo-controlled trials evaluating the effect of metformin administration on fibrinogen levels. The search included PubMed-Medline, Scopus, ISI Web of Knowledge and Google Scholar databases (by June 2, 2017) and quality of studies was performed according to Cochrane criteria. Quantitative data synthesis was conducted using a random-effects model and sensitivity analysis by the leave-one-out method. Meta-regression analysis was performed to assess the modifiers of treatment response. Meta-analysis of data from 9 randomized placebo-controlled clinical trials with 2302 patients comprising 10 treatment arms did not suggest a significant change in plasma fibrinogen concentrations following metformin therapy (WMD: -0.25 g/L, 95% CI: -0.53, 0.04, p = 0.092). The effect size was robust in the leave-one-out sensitivity analysis and remained non-significant after omission of each single study from the meta-analysis. No significant effect of metformin on plasma fibrinogen concentrations was demonstrated in the current meta-analysis. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Cost effectiveness of arthrocentesis as initial treatment for temporomandibular joint arthralgia: A randomized controlled trial

NARCIS (Netherlands)

Vos, L.M.; Stant, A.D.; Quik, E.H.; Huddleston Slater, J.J.R.; Stegenga, B.

2013-01-01

Objective: To determine the cost effectiveness of arthrocentesis as initial treatment compared to care as usual (CAU) for temporomandibular joint (TMJ) arthralgia. Materials and methods: 80 patients were randomly allocated to arthrocentesis as initial treatment (n = 40) or CAU (n = 40).

Effectiveness of a parent training program in (pre)adolescence: Evidence from a randomized controlled trial

NARCIS (Netherlands)

Leijten, P.H.O.; Overbeek, G.J.; Janssens, J.M.A.M.

2012-01-01

The present randomized controlled trial examined the effectiveness of the parent training program Parents and Children Talking Together (PCTT) for parents with children in the preadolescent period who experience parenting difficulties. The program is focused on reducing child problem behavior by

Anti-hemorrhagic effect of prophylactic tranexamic acid in benign hysterectomy-a double-blinded randomized placebo-controlled trial

DEFF Research Database (Denmark)

Topsoee, Märta Fink; Bergholt, Thomas; Ravn, Pernille

2016-01-01

and in 2004, 8% of all women in Denmark undergoing benign hysterectomy experienced a bleeding complication. Tranexamic acid is an antifibrinolytic agent that has shown to effectively reduce bleeding complications within other surgical and medical areas. However, knowledge about the drug's effect in relation...... to benign hysterectomy is still missing. OBJECTIVE: To investigate the antihemorrhagic effect of prophylactic tranexamic acid in elective benign hysterectomy. STUDY DESIGN: A double-blinded randomized placebo-controlled trial was conducted at 4 gynecological departments in Denmark from April 2013 to October...... 2014. A total of 332 women undergoing benign abdominal, laparoscopic, or vaginal hysterectomy were included in the trial, randomized to either 1 g of intravenous tranexamic acid or placebo at start of surgery. Chi-square test and Student t test statistical analyses were applied. RESULTS: The primary...

Exercise training and antioxidant supplementation independently improve cognitive function in adult male and female GFAP-APOE mice

Directory of Open Access Journals (Sweden)

Kiran Chaudhari

2014-09-01

Conclusion: Exercise was the most effective treatment at improving cognitive function in both genotypes and sex, while antioxidants seemed to be effective only in the APOE4. In young adult mice only non-spatial learning and memory were improved. The combination of the two treatments did not yield further improvement in cognition, and there was no antagonistic action of the antioxidant supplementation on the beneficial effects of exercise.

Assessing the effectiveness and cost-effectiveness of audit and feedback on physician’s prescribing indicators: study protocol of a randomized controlled trial with economic evaluation

Science.gov (United States)

2012-01-01

Background Physician prescribing is the most frequent medical intervention with a highest impact on healthcare costs and outcomes. Therefore improving and promoting rational drug use is a great interest. We aimed to assess the effectiveness and cost-effectiveness of two forms of conducting prescribing audit and feedback interventions and a printed educational material intervention in improving physician prescribing. Method/design A four-arm randomized trial with economic evaluation will be conducted in Tehran. Three interventions (routine feedback, revised feedback, and printed educational material) and a no intervention control arm will be compared. Physicians working in outpatient practices are randomly allocated to one of the four arms using stratified randomized sampling. The interventions are developed based on a review of literature, physician interviews, current experiences in Iran and with theoretical insights from the Theory of Planned Behavior. Effects of the interventions on improving antibiotics and corticosteroids prescribing will be assessed in regression analyses. Cost data will be assessed from a health care provider’s perspective and incremental cost-effectiveness ratios will be calculated. Discussion This study will determine the effectiveness and cost-effectiveness of three interventions and allow us to determine the most effective interventions in improving prescribing pattern. If the interventions are cost-effective, they will likely be applied nationwide. Trial registration Iranian Registry of Clinical Trials Registration Number: IRCT201106086740N1Pharmaceutical Sciences Research Center of TUMS Ethics Committee Registration Number: 90-02-27-07 PMID:23351564

Random distributed feedback fibre lasers

Energy Technology Data Exchange (ETDEWEB)

Turitsyn, Sergei K., E-mail: s.k.turitsyn@aston.ac.uk [Aston Institute of Photonic Technologies, Aston University, Birmingham B4 7ET (United Kingdom); Novosibirsk State University, 2 Pirogova str., 630090, Novosibirsk (Russian Federation); Babin, Sergey A. [Novosibirsk State University, 2 Pirogova str., 630090, Novosibirsk (Russian Federation); Institute of Automation and Electrometry SB RAS, 1 Ac. Koptug. ave., 630090, Novosibirsk (Russian Federation); Churkin, Dmitry V. [Aston Institute of Photonic Technologies, Aston University, Birmingham B4 7ET (United Kingdom); Novosibirsk State University, 2 Pirogova str., 630090, Novosibirsk (Russian Federation); Institute of Automation and Electrometry SB RAS, 1 Ac. Koptug. ave., 630090, Novosibirsk (Russian Federation); Vatnik, Ilya D.; Nikulin, Maxim [Institute of Automation and Electrometry SB RAS, 1 Ac. Koptug. ave., 630090, Novosibirsk (Russian Federation); Podivilov, Evgenii V. [Novosibirsk State University, 2 Pirogova str., 630090, Novosibirsk (Russian Federation); Institute of Automation and Electrometry SB RAS, 1 Ac. Koptug. ave., 630090, Novosibirsk (Russian Federation)

2014-09-10

The concept of random lasers exploiting multiple scattering of photons in an amplifying disordered medium in order to generate coherent light without a traditional laser resonator has attracted a great deal of attention in recent years. This research area lies at the interface of the fundamental theory of disordered systems and laser science. The idea was originally proposed in the context of astrophysics in the 1960s by V.S. Letokhov, who studied scattering with “negative absorption” of the interstellar molecular clouds. Research on random lasers has since developed into a mature experimental and theoretical field. A simple design of such lasers would be promising for potential applications. However, in traditional random lasers the properties of the output radiation are typically characterized by complex features in the spatial, spectral and time domains, making them less attractive than standard laser systems in terms of practical applications. Recently, an interesting and novel type of one-dimensional random laser that operates in a conventional telecommunication fibre without any pre-designed resonator mirrors–random distributed feedback fibre laser–was demonstrated. The positive feedback required for laser generation in random fibre lasers is provided by the Rayleigh scattering from the inhomogeneities of the refractive index that are naturally present in silica glass. In the proposed laser concept, the randomly backscattered light is amplified through the Raman effect, providing distributed gain over distances up to 100 km. Although an effective reflection due to the Rayleigh scattering is extremely small (∼0.1%), the lasing threshold may be exceeded when a sufficiently large distributed Raman gain is provided. Such a random distributed feedback fibre laser has a number of interesting and attractive features. The fibre waveguide geometry provides transverse confinement, and effectively one-dimensional random distributed feedback leads to the

Random distributed feedback fibre lasers

International Nuclear Information System (INIS)

Turitsyn, Sergei K.; Babin, Sergey A.; Churkin, Dmitry V.; Vatnik, Ilya D.; Nikulin, Maxim; Podivilov, Evgenii V.

2014-01-01

The concept of random lasers exploiting multiple scattering of photons in an amplifying disordered medium in order to generate coherent light without a traditional laser resonator has attracted a great deal of attention in recent years. This research area lies at the interface of the fundamental theory of disordered systems and laser science. The idea was originally proposed in the context of astrophysics in the 1960s by V.S. Letokhov, who studied scattering with “negative absorption” of the interstellar molecular clouds. Research on random lasers has since developed into a mature experimental and theoretical field. A simple design of such lasers would be promising for potential applications. However, in traditional random lasers the properties of the output radiation are typically characterized by complex features in the spatial, spectral and time domains, making them less attractive than standard laser systems in terms of practical applications. Recently, an interesting and novel type of one-dimensional random laser that operates in a conventional telecommunication fibre without any pre-designed resonator mirrors–random distributed feedback fibre laser–was demonstrated. The positive feedback required for laser generation in random fibre lasers is provided by the Rayleigh scattering from the inhomogeneities of the refractive index that are naturally present in silica glass. In the proposed laser concept, the randomly backscattered light is amplified through the Raman effect, providing distributed gain over distances up to 100 km. Although an effective reflection due to the Rayleigh scattering is extremely small (∼0.1%), the lasing threshold may be exceeded when a sufficiently large distributed Raman gain is provided. Such a random distributed feedback fibre laser has a number of interesting and attractive features. The fibre waveguide geometry provides transverse confinement, and effectively one-dimensional random distributed feedback leads to the

A randomized, controlled clinical trial: the effect of mindfulness-based cognitive therapy on generalized anxiety disorder among Chinese community patients: protocol for a randomized trial

Directory of Open Access Journals (Sweden)

Wong Samuel YS

2011-11-01

Full Text Available Abstract Background Research suggests that an eight-week Mindfulness-Based Cognitive Therapy (MBCT program may be effective in the treatment of generalized anxiety disorders. Our objective is to compare the clinical effectiveness of the MBCT program with a psycho-education programme and usual care in reducing anxiety symptoms in people suffering from generalized anxiety disorder. Methods A three armed randomized, controlled clinical trial including 9-month post-treatment follow-up is proposed. Participants screened positive using the Structure Clinical Interview for DSM-IV (SCID for general anxiety disorder will be recruited from community-based clinics. 228 participants will be randomly allocated to the MBCT program plus usual care, psycho-education program plus usual care or the usual care group. Validated Chinese version of instruments measuring anxiety and worry symptoms, depression, quality of life and health service utilization will be used. Our primary end point is the change of anxiety and worry score (Beck Anxiety Inventory and Penn State Worry Scale from baseline to the end of intervention. For primary analyses, treatment outcomes will be assessed by ANCOVA, with change in anxiety score as the baseline variable, while the baseline anxiety score and other baseline characteristics that significantly differ between groups will serve as covariates. Conclusions This is a first randomized controlled trial that compare the effectiveness of MBCT with an active control, findings will advance current knowledge in the management of GAD and the way that group intervention can be delivered and inform future research. Unique Trail Number (assigned by Centre for Clinical Trails, Clinical Trials registry, The Chinese University of Hong Kong: CUHK_CCT00267

Analysis of complex wetland ecological system: Effect of harvesting

Directory of Open Access Journals (Sweden)

Nilesh Kumar Thakur

2017-12-01

Full Text Available In this paper, we have studied interaction among diffusive phytoplankton, zooplankton and fish population with Beddington-DeAngelis type functional response for the zooplankton and Holling type III for fish. The stability analysis of the model system with diffusion and without diffusion has been analyzed. The conditions for Maximum sustainable yield and Optimal harvesting policy for non-spatial model have been discussed. Our study may be helpful to improve and manage ecosystem services provided by wetlands on an agricultural landscapes include fisheries, water conservation, climate change and many more.

Effects of oral vitamin E on treatment of atopic dermatitis: A randomized controlled trial

Directory of Open Access Journals (Sweden)

Fariba Jaffary

2015-01-01

Full Text Available Background: The pathogenesis of atopic dermatitis (AD remains to be determined; recently a possible change in the immune system with production of immunoglobulins is proposed. As vitamin E is a potent antioxidant, with the ability to decrease the serum levels of immunoglobulin E (IgE in atopic patients, we aimed to evaluate the effect of oral vitamin E on treatment of AD. Materials and Methods: This randomized, double-blind, placebo-controlled trial comprised seventy participants with mild-to-moderate AD, based on the Hanifin and Rajka diagnostic criteria. The patients were randomly selected from teaching skin clinics in Isfahan, Iran. They were randomly assigned to two groups of equal number, receiving vitamin E (400 IU/day and placebo for four 4 months. Each month, the extent, severity, and subjective symptoms including itch and sleeplessness were measured by SCORAD index. Three months after the end of intervention, the recurrence rate was assessed. Results: The improvement in all symptoms, except sleeplessness, was significantly higher in the group receiving vitamin E than in controls (-1.5 vs. 0.218 in itching, -10.85 vs. -3.54 in extent of lesion, and -11.12 vs. -3.89 in SCORAD index, respectively, P 0.05. Conclusion: This study suggests that vitamin E can improve the symptoms and the quality of life in patients with AD. As vitamin E has no side effects with a dosage of 400 IU/day, it can be recommended for the treatment of AD.

Effects of oxcarbazepine versus carbamazepine on tinnitus: A randomized double-blind placebo-controlled clinical trial.

Science.gov (United States)

Gerami, Hooshang; Saberi, Alia; Nemati, Shadman; Kazemnejad, Ehsan; Aghajanpour, Mohammad

2012-01-01

It is still a challenge to find an effective treatment for tinnitus. The aim of this study was the evaluation of carbamazepine and oxcarbazepine effects on tinnitus. In a randomized double-blind clinical trial, 57 patients who were visited in a university hospital due to chronic non-pulsatile tinnitus, were randomized in three groups and treated with carbamazepine (300-600 mg/day), oxcarbazepine (450-900 mg/day) and placebo for 12 weeks. Visual analogue scale (VAS) and tinnitus severity index (TSI) were measured in all subjects in the beginning and at the end of the 8(th) and 12(th) weeks of the trial. Data was analyzed by repeated measure analysis, paired and independent t-test. Among 51 participants who completed the trial course (28 men, 23 women), carbamazepine, oxcarbazepine and placebo decreased tinnitus severity in 56.6%, 46.2% and 38.5% of patients according to VAS, and in 61.1%, 58.8% and 50% of patients according to TSI, respectively. The effects of carbamazepine and oxcarbazepine were better in the first 8 weeks of treatment. However, their effect on tinnitus did not show any statistical difference in comparison with placebo (P = 0.34, P = 0.28). Carbamazepine and oxcarbazepine are not more effective than placebo in decreasing tinnitus severity.

Effect of cocoa and theobromine consumption on serum HDL-cholesterol concentrations: a randomized controlled trial.

Science.gov (United States)

Neufingerl, Nicole; Zebregs, Yvonne E M P; Schuring, Ewoud A H; Trautwein, Elke A

2013-06-01

Evidence from clinical studies has suggested that cocoa may increase high-density lipoprotein (HDL)-cholesterol concentrations. However, it is unclear whether this effect is attributable to flavonoids or theobromine, both of which are major cocoa components. We investigated whether pure theobromine increases serum HDL cholesterol and whether there is an interaction effect between theobromine and cocoa. The study had a 2-center, double-blind, randomized, placebo-controlled, full factorial parallel design. After a 2-wk run-in period, 152 healthy men and women (aged 40-70 y) were randomly allocated to consume one 200-mL drink/d for 4 wk that contained 1) cocoa, which naturally provided 150 mg theobromine and 325 mg flavonoids [cocoa intervention (CC)], 2) 850 mg pure theobromine [theobromine intervention (TB)], 3) cocoa and added theobromine, which provided 1000 mg theobromine and 325 mg flavonoids [theobromine and cocoa intervention (TB+CC)], or 4) neither cocoa nor theobromine (placebo). Blood lipids and apolipoproteins were measured at the start and end of interventions. In a 2-factor analysis, there was a significant main effect of the TB (P cocoa and interaction effects suggested that theobromine may be the main ingredient responsible for the HDL cholesterol-raising effect. This trial was registered at clinicaltrials.gov as NCT01481389.

Effects of PMTO in foster families with children with behavior problems : A Randomized Controlled Trial

NARCIS (Netherlands)

Maaskant, A.M.; van Rooij, F.B.; Overbeek, G.J.; Oort, F.J.; Arntz, M.; Hermanns, J.M.A.

The present randomized controlled trial examined the effectiveness of Parent Management Training Oregon for foster parents with foster children (aged 4–12) with severe externalizing behavior problems in long-term foster care arrangements. Foster children’s behavior problems are challenging for

The Effect of Random Error on Diagnostic Accuracy Illustrated with the Anthropometric Diagnosis of Malnutrition

Science.gov (United States)

2016-01-01

Background It is often thought that random measurement error has a minor effect upon the results of an epidemiological survey. Theoretically, errors of measurement should always increase the spread of a distribution. Defining an illness by having a measurement outside an established healthy range will lead to an inflated prevalence of that condition if there are measurement errors. Methods and results A Monte Carlo simulation was conducted of anthropometric assessment of children with malnutrition. Random errors of increasing magnitude were imposed upon the populations and showed that there was an increase in the standard deviation with each of the errors that became exponentially greater with the magnitude of the error. The potential magnitude of the resulting error of reported prevalence of malnutrition were compared with published international data and found to be of sufficient magnitude to make a number of surveys and the numerous reports and analyses that used these data unreliable. Conclusions The effect of random error in public health surveys and the data upon which diagnostic cut-off points are derived to define “health” has been underestimated. Even quite modest random errors can more than double the reported prevalence of conditions such as malnutrition. Increasing sample size does not address this problem, and may even result in less accurate estimates. More attention needs to be paid to the selection, calibration and maintenance of instruments, measurer selection, training & supervision, routine estimation of the likely magnitude of errors using standardization tests, use of statistical likelihood of error to exclude data from analysis and full reporting of these procedures in order to judge the reliability of survey reports. PMID:28030627

Effect of calcium from dairy and dietary supplements on faecal fat excretion: a meta-analysis of randomized controlled trials

DEFF Research Database (Denmark)

Christensen, R.; Lorenzen, Janne Kunchel; Svith, Carina Roholm

2009-01-01

Observational studies have found that dietary calcium intake is inversely related to body weight and body fat mass. One explanatory mechanism is that dietary calcium increases faecal fat excretion. To examine the effect of calcium from dietary supplements or dairy products on quantitative faecal...... fat excretion, we performed a systematic review with meta-analysis. We included randomized, controlled trials of calcium (supplements or dairy) in healthy subjects, where faecal fat excretion was measured. Meta-analyses used random-effects models with changes in faecal fat excreted expressed...

The relation between working memory and language comprehension in signers and speakers.

Science.gov (United States)

Emmorey, Karen; Giezen, Marcel R; Petrich, Jennifer A F; Spurgeon, Erin; O'Grady Farnady, Lucinda

2017-06-01

This study investigated the relation between linguistic and spatial working memory (WM) resources and language comprehension for signed compared to spoken language. Sign languages are both linguistic and visual-spatial, and therefore provide a unique window on modality-specific versus modality-independent contributions of WM resources to language processing. Deaf users of American Sign Language (ASL), hearing monolingual English speakers, and hearing ASL-English bilinguals completed several spatial and linguistic serial recall tasks. Additionally, their comprehension of spatial and non-spatial information in ASL and spoken English narratives was assessed. Results from the linguistic serial recall tasks revealed that the often reported advantage for speakers on linguistic short-term memory tasks does not extend to complex WM tasks with a serial recall component. For English, linguistic WM predicted retention of non-spatial information, and both linguistic and spatial WM predicted retention of spatial information. For ASL, spatial WM predicted retention of spatial (but not non-spatial) information, and linguistic WM did not predict retention of either spatial or non-spatial information. Overall, our findings argue against strong assumptions of independent domain-specific subsystems for the storage and processing of linguistic and spatial information and furthermore suggest a less important role for serial encoding in signed than spoken language comprehension. Copyright © 2017 Elsevier B.V. All rights reserved.

Individual and school level effects of perceived harm, perceived availability, and community size on marijuana use among 12th-grade students: a random effects model.

Science.gov (United States)

Swaim, Randall C

2003-06-01

A hierarchical linear model was used to estimate the individual and school level effects for marijuana use among a national sample of 12th-grade students. School effects were small in comparison to individual level effects, accounting for 2.9% of the variance in marijuana use. At the individual level, perceived harm, perceived availability, and their interaction were significant predictors, each of which varied randomly across schools. Among two school-level predictors, the normative environment for perceived harm was not significant, but normative perceived availability predicted level of marijuana use. The effect of perceived availability on marijuana use was stronger in larger, compared to smaller communities. Results are discussed in light of the use of random regression methods for identifying school-specific patterns of risk and protection for prevention planning.

How random is a random vector?

International Nuclear Information System (INIS)

Eliazar, Iddo

2015-01-01

Over 80 years ago Samuel Wilks proposed that the “generalized variance” of a random vector is the determinant of its covariance matrix. To date, the notion and use of the generalized variance is confined only to very specific niches in statistics. In this paper we establish that the “Wilks standard deviation” –the square root of the generalized variance–is indeed the standard deviation of a random vector. We further establish that the “uncorrelation index” –a derivative of the Wilks standard deviation–is a measure of the overall correlation between the components of a random vector. Both the Wilks standard deviation and the uncorrelation index are, respectively, special cases of two general notions that we introduce: “randomness measures” and “independence indices” of random vectors. In turn, these general notions give rise to “randomness diagrams”—tangible planar visualizations that answer the question: How random is a random vector? The notion of “independence indices” yields a novel measure of correlation for Lévy laws. In general, the concepts and results presented in this paper are applicable to any field of science and engineering with random-vectors empirical data.

How random is a random vector?

Science.gov (United States)

Eliazar, Iddo

2015-12-01

Over 80 years ago Samuel Wilks proposed that the "generalized variance" of a random vector is the determinant of its covariance matrix. To date, the notion and use of the generalized variance is confined only to very specific niches in statistics. In this paper we establish that the "Wilks standard deviation" -the square root of the generalized variance-is indeed the standard deviation of a random vector. We further establish that the "uncorrelation index" -a derivative of the Wilks standard deviation-is a measure of the overall correlation between the components of a random vector. Both the Wilks standard deviation and the uncorrelation index are, respectively, special cases of two general notions that we introduce: "randomness measures" and "independence indices" of random vectors. In turn, these general notions give rise to "randomness diagrams"-tangible planar visualizations that answer the question: How random is a random vector? The notion of "independence indices" yields a novel measure of correlation for Lévy laws. In general, the concepts and results presented in this paper are applicable to any field of science and engineering with random-vectors empirical data.

Effectiveness of antidepressants: an evidence myth constructed from a thousand randomized trials?

Directory of Open Access Journals (Sweden)

Ioannidis John PA

2008-05-01

Full Text Available Abstract Antidepressants, in particular newer agents, are among the most widely prescribed medications worldwide with annual sales of billions of dollars. The introduction of these agents in the market has passed through seemingly strict regulatory control. Over a thousand randomized trials have been conducted with antidepressants. Statistically significant benefits have been repeatedly demonstrated and the medical literature is flooded with several hundreds of "positive" trials (both pre-approval and post-approval. However, two recent meta-analyses question this picture. The first meta-analysis used data that were submitted to FDA for the approval of 12 antidepressant drugs. While only half of these trials had formally significant effectiveness, published reports almost ubiquitously claimed significant results. "Negative" trials were either left unpublished or were distorted to present "positive" results. The average benefit of these drugs based on the FDA data was of small magnitude, while the published literature suggested larger benefits. A second meta-analysis using also FDA-submitted data examined the relationship between treatment effect and baseline severity of depression. Drug-placebo differences increased with increasing baseline severity and the difference became large enough to be clinically important only in the very small minority of patient populations with severe major depression. In severe major depression, antidepressants did not become more effective, simply placebo lost effectiveness. These data suggest that antidepressants may be less effective than their wide marketing suggests. Short-term benefits are small and long-term balance of benefits and harms is understudied. I discuss how the use of many small randomized trials with clinically non-relevant outcomes, improper interpretation of statistical significance, manipulated study design, biased selection of study populations, short follow-up, and selective and distorted

Randomized random walk on a random walk

International Nuclear Information System (INIS)

Lee, P.A.

1983-06-01

This paper discusses generalizations of the model introduced by Kehr and Kunter of the random walk of a particle on a one-dimensional chain which in turn has been constructed by a random walk procedure. The superimposed random walk is randomised in time according to the occurrences of a stochastic point process. The probability of finding the particle in a particular position at a certain instant is obtained explicitly in the transform domain. It is found that the asymptotic behaviour for large time of the mean-square displacement of the particle depends critically on the assumed structure of the basic random walk, giving a diffusion-like term for an asymmetric walk or a square root law if the walk is symmetric. Many results are obtained in closed form for the Poisson process case, and these agree with those given previously by Kehr and Kunter. (author)

Modeling Alaska boreal forests with a controlled trend surface approach

Science.gov (United States)

Mo Zhou; Jingjing Liang

2012-01-01

An approach of Controlled Trend Surface was proposed to simultaneously take into consideration large-scale spatial trends and nonspatial effects. A geospatial model of the Alaska boreal forest was developed from 446 permanent sample plots, which addressed large-scale spatial trends in recruitment, diameter growth, and mortality. The model was tested on two sets of...

QUASI-RANDOM TESTING OF COMPUTER SYSTEMS

Directory of Open Access Journals (Sweden)

S. V. Yarmolik

2013-01-01

Full Text Available Various modified random testing approaches have been proposed for computer system testing in the black box environment. Their effectiveness has been evaluated on the typical failure patterns by employing three measures, namely, P-measure, E-measure and F-measure. A quasi-random testing, being a modified version of the random testing, has been proposed and analyzed. The quasi-random Sobol sequences and modified Sobol sequences are used as the test patterns. Some new methods for Sobol sequence generation have been proposed and analyzed.

Effect of acupuncture on insomnia following stroke: study protocol for a randomized controlled trial.

Science.gov (United States)

Cao, Yan; Yin, Xuan; Soto-Aguilar, Francisca; Liu, Yiping; Yin, Ping; Wu, Junyi; Zhu, Bochang; Li, Wentao; Lao, Lixing; Xu, Shifen

2016-11-16

The incidence, mortality, and prevalence of stroke are high in China. Stroke is commonly associated with insomnia; both insomnia and stroke have been effectively treated with acupuncture for a long time. The aim of this proposed trial is to assess the therapeutic effect of acupuncture on insomnia following stroke. This proposed study is a single-center, single-blinded (patient-assessor-blinded), parallel-group randomized controlled trial. We will randomly assign 60 participants with insomnia following stroke into two groups in a 1:1 ratio. The intervention group will undergo traditional acupuncture that achieves the De-qi sensation, and the control group will receive sham acupuncture without needle insertion. The same acupoints (DU20, DU24, EX-HN3, EX-HN22, HT7, and SP6) will be used in both groups. Treatments will be given to all participants three times a week for the subsequent 4 weeks. The primary outcome will be the Pittsburgh Sleep Quality Index. The secondary outcomes will be: the Insomnia Severity Index; sleep efficacy, sleep awakenings, and total sleep time recorded via actigraphy; the National Institutes of Health Stroke Scale; the Stroke-Specific Quality of Life score; the Hospital Anxiety and Depression Scale. The use of estazolam will be permitted and regulated under certain conditions. Outcomes will be assessed at baseline, 2 weeks after treatment commencement, 4 weeks after treatment commencement, and at the 8-week follow-up. This proposed study will contribute to expanding knowledge about acupuncture treatment for insomnia following stroke. This will be a high-quality randomized controlled trial with strict methodology and few design deficits. It will investigate the effectiveness of acupuncture as an alternative treatment for insomnia following stroke. Chinese Clinical Trial Registry identifier: ChiCTR-IIC-16008382 . Registered on 28 April 2016.

Random safety auditing, root cause analysis, failure mode and effects analysis.

Science.gov (United States)

Ursprung, Robert; Gray, James

2010-03-01

Improving quality and safety in health care is a major concern for health care providers, the general public, and policy makers. Errors and quality issues are leading causes of morbidity and mortality across the health care industry. There is evidence that patients in the neonatal intensive care unit (NICU) are at high risk for serious medical errors. To facilitate compliance with safe practices, many institutions have established quality-assurance monitoring procedures. Three techniques that have been found useful in the health care setting are failure mode and effects analysis, root cause analysis, and random safety auditing. When used together, these techniques are effective tools for system analysis and redesign focused on providing safe delivery of care in the complex NICU system. Copyright 2010 Elsevier Inc. All rights reserved.

Design, and participant enrollment, of a randomized controlled trial evaluating effectiveness and cost-effectiveness of a community-based case management intervention, for patients suffering from COPD

DEFF Research Database (Denmark)

Sørensen, Sabrina Storgaard; Pedersen, Kjeld Møller; Weinreich, Ulla Møller

2015-01-01

Background: Case management interventions are recommended to improve quality of care and reduce costs in chronic care, but further evidence on effectiveness and cost-effectiveness is needed. The objective of this study is the reporting of the design and participant enrollment of a randomized...... controlled trial, conducted to evaluate the effectiveness and cost-effectiveness of a community-based case management model for patients suffering from chronic obstructive pulmonary disease (COPD). With a focus on support for self-care and care coordination, the intervention was hypothesized to result...... patients were randomized into two groups: the case-managed group and the usual-care group. Participant characteristics were obtained at baseline, and measures on effectiveness and costs were obtained through questionnaires and registries within a 12-month follow-up period. In the forthcoming analysis...

The novel dehydroepiandrosterone (DHEA) derivative BNN27 counteracts delay-dependent and scopolamine-induced recognition memory deficits in rats.

Science.gov (United States)

Pitsikas, Nikolaos; Gravanis, Achille

2017-04-01

Experimental evidence indicates that the neurosteroids dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulphate (DHEAS) are involved in cognition. BNN27 is a novel 17C spiroepoxy-DHEA derivative, which devoid of steroidogenic activity. The neuroprotective effects of BNN27 have been recently reported. The present study was designed to investigate the effects of BNN27 on recognition memory in rats. For this purpose, the novel object task (NOT), a procedure assessing non-spatial recognition memory and the novel location task (NLT), a procedure evaluating spatial recognition memory were used. Intraperitoneal (i.p.) administration of BNN27 (3 and 10mg/kg) antagonized delay-dependent deficits in the NOT in the normal rat, suggesting that this DHEA derivative affected acquisition, storage and retrieval of information. In addition, BNN27 (3 and 10mg/kg, i.p.) counteracted the scopolamine [0.2mg/kg, subcutaneously (s.c.)]-induced non-spatial and spatial recognition memory deficits. These findings suggest that BNN27 may modulate different aspects of recognition memory, potentially interacting with the cholinergic system, relevant to cognition. Copyright © 2017 Elsevier Inc. All rights reserved.

Random matrix approach to plasmon resonances in the random impedance network model of disordered nanocomposites

Science.gov (United States)

Olekhno, N. A.; Beltukov, Y. M.

2018-05-01

Random impedance networks are widely used as a model to describe plasmon resonances in disordered metal-dielectric and other two-component nanocomposites. In the present work, the spectral properties of resonances in random networks are studied within the framework of the random matrix theory. We have shown that the appropriate ensemble of random matrices for the considered problem is the Jacobi ensemble (the MANOVA ensemble). The obtained analytical expressions for the density of states in such resonant networks show a good agreement with the results of numerical simulations in a wide range of metal filling fractions 0

effective medium approximation is observed.

Effects of professional oral health care on elderly: randomized trial.

Science.gov (United States)

Morino, T; Ookawa, K; Haruta, N; Hagiwara, Y; Seki, M

2014-11-01

To better understand the role of the professional oral health care for elderly in improving geriatric oral health, the effects of short-term professional oral health care (once per week for 1 month) on oral microbiological parameters were assessed. Parallel, open-labelled, randomize-controlled trial was undertaken in a nursing home for elderly in Shizuoka, Japan. Thirty-four dentate elderly over 74 years were randomly assigned from ID number to the intervention (17/34) and control (17/34) groups. The outcomes were changes in oral microbiological parameters (number of bacteria in unstimulated saliva; whole bacteria, Streptococcus, Fusobacterium and Prevotella: opportunistic pathogens detection: and index of oral hygiene evaluation [Dental Plaque Index, DPI]) within the intervention period. Each parameter was evaluated at before and after intervention period. Four elderly were lost from mortality (1), bone fracture (1), refused to participate (1) and multi-antibiotics usage (1). Finally, 30 elderly were analysed (14/intervention and 16/control). At baseline, no difference was found between the control and intervention groups. After the intervention period, the percentage of Streptococcus species increased significantly in the intervention group (Intervention, 86% [12/14]; Control, 50% [8/16]: Fisher's, right-tailed, P oral health care can improve oral conditions in the elderly. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Neurocognitive effects of neurofeedback in adolescents with ADHD: a randomized controlled trial.

Science.gov (United States)

Bink, Marleen; van Nieuwenhuizen, Chijs; Popma, Arne; Bongers, Ilja L; van Boxtel, Geert J M

2014-05-01

Neurofeedback aims to reduce symptoms of attention-deficit/hyperactivity disorder (ADHD), mainly attention problems. However, the additional influence of neurofeedback over treatment as usual (TAU) on neurocognitive functioning for adolescents with ADHD remains unclear. By using a multicenter parallel randomized controlled trial (RCT) design, male adolescents with a DSM-IV-TR diagnosis of ADHD (mean age = 16.1 years; range, 12-24) were randomized to receive either a combination of TAU and neurofeedback (n = 45) or TAU (n = 26). Randomization was computer generated and stratified by age group (ages 12 through 15, 16 through 20, and 21 through 24 years). The neurofeedback intervention consisted of approximately 37 sessions over a period of 25 weeks of theta/sensorimotor rhythm training on the vertex (Cz). Primary neurocognitive outcomes included performance parameters derived from the D2 Test of Attention, the Digit Span backward, the Stroop Color-Word Test and the Tower of London, all assessed preintervention and postintervention. Data were collected between December 2009 and July 2012. At postintervention, outcomes of attention and/or motor speed were improved, with faster processing times for both intervention conditions and with medium to large effect sizes (range, ηp2 = .08-.54; P values neurofeedback over TAU was observed. Hence, this study does not provide evidence for using theta/sensorimotor rhythm neurofeedback to enhance neurocognitive performance as additional intervention to TAU for adolescents with ADHD symptoms. Trialregister.nl identifier: 1759. © Copyright 2014 Physicians Postgraduate Press, Inc.

Universal Prevention for Anxiety and Depressive Symptoms in Children: A Meta-analysis of Randomized and Cluster-Randomized Trials.

Science.gov (United States)

Ahlen, Johan; Lenhard, Fabian; Ghaderi, Ata

2015-12-01

Although under-diagnosed, anxiety and depression are among the most prevalent psychiatric disorders in children and adolescents, leading to severe impairment, increased risk of future psychiatric problems, and a high economic burden to society. Universal prevention may be a potent way to address these widespread problems. There are several benefits to universal relative to targeted interventions because there is limited knowledge as to how to screen for anxiety and depression in the general population. Earlier meta-analyses of the prevention of depression and anxiety symptoms among children suffer from methodological inadequacies such as combining universal, selective, and indicated interventions in the same analyses, and comparing cluster-randomized trials with randomized trials without any correction for clustering effects. The present meta-analysis attempted to determine the effectiveness of universal interventions to prevent anxiety and depressive symptoms after correcting for clustering effects. A systematic search of randomized studies in PsychINFO, Cochrane Library, and Google Scholar resulted in 30 eligible studies meeting inclusion criteria, namely peer-reviewed, randomized or cluster-randomized trials of universal interventions for anxiety and depressive symptoms in school-aged children. Sixty-three percent of the studies reported outcome data regarding anxiety and 87 % reported outcome data regarding depression. Seventy percent of the studies used randomization at the cluster level. There were small but significant effects regarding anxiety (.13) and depressive (.11) symptoms as measured at immediate posttest. At follow-up, which ranged from 3 to 48 months, effects were significantly larger than zero regarding depressive (.07) but not anxiety (.11) symptoms. There was no significant moderation effect of the following pre-selected variables: the primary aim of the intervention (anxiety or depression), deliverer of the intervention, gender distribution

Effectiveness of acupuncture for angina pectoris: a systematic review of randomized controlled trials.

Science.gov (United States)

Yu, Changhe; Ji, Kangshou; Cao, Huijuan; Wang, Ying; Jin, Hwang Hye; Zhang, Zhe; Yang, Guanlin

2015-03-28

The purpose of this systematic review is to assess the effectiveness of acupuncture for angina pectoris. Eleven electronic databases were searched until January 2013. The study included randomized controlled trials that the effectiveness of acupuncture alone was compared to anti-angina medicines (in addition to conventional treatment) and the effectiveness of a combination of acupuncture plus anti-angina medicines was compared to anti-angina medicines alone. The trial selection, data extraction, quality assessment and data analytic procedures outlined in the 2011 Cochrane Handbook were involved. The study included 25 randomized controlled trials (involving 2,058 patients) that met our inclusion criteria. The pooled results showed that the number of patients with ineffectiveness of angina relief was less in the combined acupuncture-anti-angina treatment group than in the anti-angina medicines alone group (RR 0.33, 95% CI 0.23-0.47, p angina medicines alone group, fewer patients in the combined treatment group showed no ECG improvement (RR 0.50, 95% CI 0.40-0.62, p angina medicines alone for both outcome measures. Only four trials mentioned adverse effects. One trial found no significant difference between acupuncture and Chinese medicine, and three reported no adverse events. The quality of the trials was found to be low. The findings showed very low evidence to support the use of acupuncture for improving angina symptoms and ECG of angina patients. However, the quality of the trials included in this study was low. Large and rigorously designed trials are needed to confirm the potential benefit and adverse events of acupuncture.

The effects of educating mothers and girls on the girls' attitudes toward puberty health: a randomized controlled trial.

Science.gov (United States)

Afsari, Atousa; Mirghafourvand, Mojgan; Valizadeh, Sousan; Abbasnezhadeh, Massomeh; Galshi, Mina; Fatahi, Samira

2017-04-01

The attitude of a girl toward her menstruation and puberty has a considerable impact on her role during motherhood, social adjustment, and future marital life. This study was conducted in 2014 with the aim of comparing the effects of educating mothers and girls on the attitudes of adolescent girls of Tabriz City, Iran, towards puberty health. This randomized control clinical trial was conducted on 364 adolescent girls who experienced menstruation. Twelve schools were selected randomly among 107 secondary schools for girls. One-third of the students of each school were selected randomly using a table of random numbers and socio-demographic and each participant was asked to answer the attitude questionnaires. The schools were randomly allocated to the groups of mother's education, girl's education, and no-intervention. The attitude questionnaire was filled out by the participants again 2 months after intervention. The general linear model, in which the baseline values were controlled, was employed to compare the scores of the three groups after the intervention. No significant differences were observed among the three groups in terms of the attitude score before intervention (p>0.05). Attitude score improvement after intervention in the girl's education group was significantly higher than the one of both mother's education (adjusted mean difference [AMD]: 1.8; [95% confidence interval (CI): 0.4-1.3]) and no-intervention groups (AMD: 1.3; [95% CI: 0.0-2.6]) by controlling the attitude score before intervention. Based on the findings, it is more effective to educate girls directly about puberty health to improve adolescent girls' attitudes than educating mothers and asking them to transfer information to the girls. Nevertheless, studies with longer training period and follow-up are proposed to determine the effects of educating girls (through their mothers) on their attitudes about puberty health.

Effect of botulinum toxin A and nitroglycerin on random skin flap survival in rats.

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Ghanbarzadeh, Kourosh; Tabatabaie, Omid Reza; Salehifar, Ebrahim; Amanlou, Massoud; Khorasani, Ghasemali

2016-01-01

A suitable pharmacological substitute for the well-established surgical delay technique for random skin flaps to increase viability has been elusive. To evaluate the effects of nitroglycerin and botulinum toxin type A on random flap survival in a rat model. The present controlled experimental study was performed in the four groups of rats. One week after intervention in each group, the flap was raised and kept in situ, and flap necrosis was evaluated through follow-up. Group 1 received intradermal botulinum toxin type A (BTX-A) and topical nitroglycerin 2%; group 2 received BTX-A and topical Vaseline (Unilever, USA); group 3 received topical nitroglycerin and intradermal normal saline; and group 4 received topical Vaseline and intradermal normal saline. BTX-A reduced the area of necrosis compared with control (24% versus 56% respectively; P<0.001). Nitroglycerin application was associated with a trend toward improved flap viability (42% versus 56%; P=0.059). The combination of topical nitroglycerin and BTX-A, compared with Vaseline and BTX-A, was associated with decreased flap necrosis (16.1% versus 24%, respectively), although it was not statistically significant (P=0.45). BTX-A was effective in reducing distal flap necrosis. The effect of BTX-A was significantly more pronounced than nitroglycerin ointment.

LED Lighting System Reliability Modeling and Inference via Random Effects Gamma Process and Copula Function

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Huibing Hao

2015-01-01

Full Text Available Light emitting diode (LED lamp has attracted increasing interest in the field of lighting systems due to its low energy and long lifetime. For different functions (i.e., illumination and color, it may have two or more performance characteristics. When the multiple performance characteristics are dependent, it creates a challenging problem to accurately analyze the system reliability. In this paper, we assume that the system has two performance characteristics, and each performance characteristic is governed by a random effects Gamma process where the random effects can capture the unit to unit differences. The dependency of performance characteristics is described by a Frank copula function. Via the copula function, the reliability assessment model is proposed. Considering the model is so complicated and analytically intractable, the Markov chain Monte Carlo (MCMC method is used to estimate the unknown parameters. A numerical example about actual LED lamps data is given to demonstrate the usefulness and validity of the proposed model and method.

Completion report : Effect of Comprehensive Yogic Breathing program on type 2 diabetes: A randomized control trial

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V P Jyotsna

2014-01-01

Full Text Available Background: Yoga has been shown to be benefi cial in diabetes in many studies, though randomized control trials are few. The aim of this randomized control trial was to see the effect of Sudarshan Kriya and related practices (comprehensive yogic breathing program on quality of life, glycemic control, and cardiac autonomic functions in diabetes. Diabetes mellitus is a risk factor for sudden cardiac death. Cardiac autonomic neuropathy has been implicated in the causation of sudden cardiac death. Therefore, a maneuver to prevent progression of cardiac autonomic neuropathy holds signifi cance. Materials and Methods: A total of 120 patients of diabetes on oral medication and diet and exercise advice were randomized into two groups: (1 Continued to receive standard treatment for diabetes. (2 Patients administered comprehensive yogic breathing program and monitored to regularly practice yoga in addition to standard treatment of diabetes. At 6 months, quality of life and postprandial plasma glucose signifi cantly improved in the group practicing yoga compared to baseline, but there was no significant improvement in the fasting plasma glucose and glycated hemoglobin. Results: On per protocol analysis, sympathetic cardiac autonomic functions signifi cantly improved from baseline in the group practicing comprehensive yogic breathing. Conclusion: This randomized control trial points towards the beneficial effect of yogic breathing program in preventing progression of cardiac neuropathy. This has important implications as cardiac autonomic neuropathy has been considered as one of the factors for sudden cardiac deaths.Keywords: comprehensive yogic breathing program, diabetes mellitus, cardiac autonomic function

Effects of oral vitamin E on treatment of atopic dermatitis: A randomized controlled trial.

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Jaffary, Fariba; Faghihi, Gita; Mokhtarian, Arghavan; Hosseini, Sayed Mohsen

2015-11-01

The pathogenesis of atopic dermatitis (AD) remains to be determined; recently a possible change in the immune system with production of immunoglobulins is proposed. As vitamin E is a potent antioxidant, with the ability to decrease the serum levels of immunoglobulin E (IgE) in atopic patients, we aimed to evaluate the effect of oral vitamin E on treatment of AD. This randomized, double-blind, placebo-controlled trial comprised seventy participants with mild-to-moderate AD, based on the Hanifin and Rajka diagnostic criteria. The patients were randomly selected from teaching skin clinics in Isfahan, Iran. They were randomly assigned to two groups of equal number, receiving vitamin E (400 IU/day) and placebo for four 4 months. Each month, the extent, severity, and subjective symptoms including itch and sleeplessness were measured by SCORAD index. Three months after the end of intervention, the recurrence rate was assessed. The improvement in all symptoms, except sleeplessness, was significantly higher in the group receiving vitamin E than in controls (-1.5 vs. 0.218 in itching, -10.85 vs. -3.54 in extent of lesion, and -11.12 vs. -3.89 in SCORAD index, respectively, P vitamin E compared to the placebo group was 1.17, without significant differences between the two groups (P > 0.05). This study suggests that vitamin E can improve the symptoms and the quality of life in patients with AD. As vitamin E has no side effects with a dosage of 400 IU/day, it can be recommended for the treatment of AD.

Source-Independent Quantum Random Number Generation

Science.gov (United States)

Cao, Zhu; Zhou, Hongyi; Yuan, Xiao; Ma, Xiongfeng

2016-01-01

Quantum random number generators can provide genuine randomness by appealing to the fundamental principles of quantum mechanics. In general, a physical generator contains two parts—a randomness source and its readout. The source is essential to the quality of the resulting random numbers; hence, it needs to be carefully calibrated and modeled to achieve information-theoretical provable randomness. However, in practice, the source is a complicated physical system, such as a light source or an atomic ensemble, and any deviations in the real-life implementation from the theoretical model may affect the randomness of the output. To close this gap, we propose a source-independent scheme for quantum random number generation in which output randomness can be certified, even when the source is uncharacterized and untrusted. In our randomness analysis, we make no assumptions about the dimension of the source. For instance, multiphoton emissions are allowed in optical implementations. Our analysis takes into account the finite-key effect with the composable security definition. In the limit of large data size, the length of the input random seed is exponentially small compared to that of the output random bit. In addition, by modifying a quantum key distribution system, we experimentally demonstrate our scheme and achieve a randomness generation rate of over 5 ×103 bit /s .

Computer generation of random deviates

International Nuclear Information System (INIS)

Cormack, John

1991-01-01

The need for random deviates arises in many scientific applications. In medical physics, Monte Carlo simulations have been used in radiology, radiation therapy and nuclear medicine. Specific instances include the modelling of x-ray scattering processes and the addition of random noise to images or curves in order to assess the effects of various processing procedures. Reliable sources of random deviates with statistical properties indistinguishable from true random deviates are a fundamental necessity for such tasks. This paper provides a review of computer algorithms which can be used to generate uniform random deviates and other distributions of interest to medical physicists, along with a few caveats relating to various problems and pitfalls which can occur. Source code listings for the generators discussed (in FORTRAN, Turbo-PASCAL and Data General ASSEMBLER) are available on request from the authors. 27 refs., 3 tabs., 5 figs

A practical guide and power analysis for GLMMs: detecting among treatment variation in random effects

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Morgan P. Kain

2015-09-01

Full Text Available In ecology and evolution generalized linear mixed models (GLMMs are becoming increasingly used to test for differences in variation by treatment at multiple hierarchical levels. Yet, the specific sampling schemes that optimize the power of an experiment to detect differences in random effects by treatment/group remain unknown. In this paper we develop a blueprint for conducting power analyses for GLMMs focusing on detecting differences in variance by treatment. We present parameterization and power analyses for random-intercepts and random-slopes GLMMs because of their generality as focal parameters for most applications and because of their immediate applicability to emerging questions in the field of behavioral ecology. We focus on the extreme case of hierarchically structured binomial data, though the framework presented here generalizes easily to any error distribution model. First, we determine the optimal ratio of individuals to repeated measures within individuals that maximizes power to detect differences by treatment in among-individual variation in intercept, among-individual variation in slope, and within-individual variation in intercept. Second, we explore how power to detect differences in target variance parameters is affected by total variation. Our results indicate heterogeneity in power across ratios of individuals to repeated measures with an optimal ratio determined by both the target variance parameter and total sample size. Additionally, power to detect each variance parameter was low overall (in most cases >1,000 total observations per treatment needed to achieve 80% power and decreased with increasing variance in non-target random effects. With growing interest in variance as the parameter of inquiry, these power analyses provide a crucial component for designing experiments focused on detecting differences in variance. We hope to inspire novel experimental designs in ecology and evolution investigating the causes and

Effectiveness and moderators of the preventive intervention kids in divorce situations: A randomized controlled trial.

Science.gov (United States)

Pelleboer-Gunnink, Hannah A; Van der Valk, Inge E; Branje, Susan J T; Van Doorn, Muriel D; Deković, Maja

2015-10-01

Children of divorced parents have an increased risk of a variety of problems in comparison to children from intact families. Therefore, several intervention programs have been developed directed at children of divorced parents. Yet, empirical data on the effectiveness of these interventions are limited. This study evaluated the school-based, child-directed prevention program Kids In Divorce Situations (KIDS) using a randomized controlled trial. The sample consisted of 156 children randomly assigned at the school level into an experimental (80 children) and control condition (76 children). In addition, 131 mothers and 76 fathers participated in the study. Four assessments took place: a pretest, a posttest, and two follow-up assessments conducted 6 months and 1 year after finishing KIDS. Latent growth analyses demonstrated that the intervention significantly reduced child-reported emotional problems and enhanced child-reported communication with the father and mother-reported communication with the child. The effect sizes ranged from .30-.63. Few moderation effects of gender, time since divorce, or perceived parental conflict on the intervention effects were found. After parental divorce, a limited school-based intervention for children can be efficacious in promoting children's emotional well-being and parent-child communication. (c) 2015 APA, all rights reserved).

The effects of transcranial magnetic stimulation over the dorsolateral prefrontal cortex on suppression of habitual counting during random number generation.

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Jahanshahi, M; Profice, P; Brown, R G; Ridding, M C; Dirnberger, G; Rothwell, J C

1998-08-01

Random number generation is an attention-demanding task that engages working memory and executive processes. Random number generation requires holding information 'on line', suppression of habitual counting, internally driven response generation and monitoring of responses. Evidence from PET studies suggests that the dorsolateral prefrontal cortex (DLPFC) is involved in the generation of random responses. We examined the effects of short trains of transcranial magnetic stimulation (TMS) over the left or right DLPFC or medial frontal cortex on random number generation in healthy normal participants. As in previous evidence, in control trials without stimulation participants performed poorly on the random number generation task, showing repetition avoidance and a tendency to count. Brief disruption of processing with TMS over the left DLPFC changed the balance of the individuals' counting bias, increasing the most habitual counting in ones and reducing the lower probability response of counting in twos. This differential effect of TMS over the left DLPFC on the balance of the subject's counting bias was not obtained with TMS over the right DLPFC or the medial frontal cortex. The results suggest that, with disruption of the left DLPFC with TMS, habitual counting in ones that has previously been suppressed is released from inhibition. From these findings a network modulation model of random number generation is proposed, whereby suppression of habitual responses is achieved through the modulatory influence of the left DLPFC over a number-associative network in the superior temporal cortex. To allow emergence of appropriate random responses, the left DLPFC inhibits the superior temporal cortex to prevent spreading activation and habitual counting in ones.

The effectiveness of lifestyle triple P in the Netherlands: a randomized controlled trial.

Science.gov (United States)

Gerards, Sanne M P L; Dagnelie, Pieter C; Gubbels, Jessica S; van Buuren, Stef; Hamers, Femke J M; Jansen, Maria W J; van der Goot, Odilia H M; de Vries, Nanne K; Sanders, Matthew R; Kremers, Stef P J

2015-01-01

Lifestyle Triple P is a general parenting intervention which focuses on preventing further excessive weight gain in overweight and obese children. The objective of the current study was to assess the effectiveness of the Lifestyle Triple P intervention in the Netherlands. We used a parallel randomized controlled design to test the effectiveness of the intervention. In total, 86 child-parent triads (children 4-8 years old, overweight or obese) were recruited and randomly assigned (allocation ratio 1:1) to the Lifestyle Triple P intervention or the control condition. Parents in the intervention condition received a 14-week intervention consisting of ten 90-minute group sessions and four individual telephone sessions. Primary outcome measure was the children's body composition (BMI z-scores, waist circumference and skinfolds). The research assistant who performed the measurements was blinded for group assignment. Secondary outcome measures were the children's dietary behavior and physical activity level, parenting practices, parental feeding style, parenting style, and parental self-efficacy. Outcome measures were assessed at baseline and 4 months (short-term) and 12 months (long-term) after baseline. Multilevel multiple regression analyses were conducted to determine the effect of the intervention on primary and secondary outcome measures. No intervention effects were found on children's body composition. Analyses of secondary outcomes showed positive short-term intervention effects on children's soft-drink consumption and parental responsibility regarding physical activity, encouragement to eat, psychological control, and efficacy and satisfaction with parenting. Longer-term intervention effects were found on parent's report of children's time spent on sedentary behavior and playing outside, parental monitoring food intake, and responsibility regarding nutrition. Although the Lifestyle Triple P intervention showed positive effects on some parent reported child

The effectiveness of lifestyle triple P in the Netherlands: a randomized controlled trial.

Directory of Open Access Journals (Sweden)

Sanne M P L Gerards

Full Text Available Lifestyle Triple P is a general parenting intervention which focuses on preventing further excessive weight gain in overweight and obese children. The objective of the current study was to assess the effectiveness of the Lifestyle Triple P intervention in the Netherlands.We used a parallel randomized controlled design to test the effectiveness of the intervention. In total, 86 child-parent triads (children 4-8 years old, overweight or obese were recruited and randomly assigned (allocation ratio 1:1 to the Lifestyle Triple P intervention or the control condition. Parents in the intervention condition received a 14-week intervention consisting of ten 90-minute group sessions and four individual telephone sessions. Primary outcome measure was the children's body composition (BMI z-scores, waist circumference and skinfolds. The research assistant who performed the measurements was blinded for group assignment. Secondary outcome measures were the children's dietary behavior and physical activity level, parenting practices, parental feeding style, parenting style, and parental self-efficacy. Outcome measures were assessed at baseline and 4 months (short-term and 12 months (long-term after baseline. Multilevel multiple regression analyses were conducted to determine the effect of the intervention on primary and secondary outcome measures.No intervention effects were found on children's body composition. Analyses of secondary outcomes showed positive short-term intervention effects on children's soft-drink consumption and parental responsibility regarding physical activity, encouragement to eat, psychological control, and efficacy and satisfaction with parenting. Longer-term intervention effects were found on parent's report of children's time spent on sedentary behavior and playing outside, parental monitoring food intake, and responsibility regarding nutrition.Although the Lifestyle Triple P intervention showed positive effects on some parent reported

The Effectiveness of Lifestyle Triple P in the Netherlands: A Randomized Controlled Trial

Science.gov (United States)

Gerards, Sanne M. P. L.; Dagnelie, Pieter C.; Gubbels, Jessica S.; van Buuren, Stef; Hamers, Femke J. M.; Jansen, Maria W. J.; van der Goot, Odilia H. M.; de Vries, Nanne K.; Sanders, Matthew R.; Kremers, Stef P. J.

2015-01-01

Introduction Lifestyle Triple P is a general parenting intervention which focuses on preventing further excessive weight gain in overweight and obese children. The objective of the current study was to assess the effectiveness of the Lifestyle Triple P intervention in the Netherlands. Method We used a parallel randomized controlled design to test the effectiveness of the intervention. In total, 86 child-parent triads (children 4–8 years old, overweight or obese) were recruited and randomly assigned (allocation ratio 1:1) to the Lifestyle Triple P intervention or the control condition. Parents in the intervention condition received a 14-week intervention consisting of ten 90-minute group sessions and four individual telephone sessions. Primary outcome measure was the children’s body composition (BMI z-scores, waist circumference and skinfolds). The research assistant who performed the measurements was blinded for group assignment. Secondary outcome measures were the children’s dietary behavior and physical activity level, parenting practices, parental feeding style, parenting style, and parental self-efficacy. Outcome measures were assessed at baseline and 4 months (short-term) and 12 months (long-term) after baseline. Multilevel multiple regression analyses were conducted to determine the effect of the intervention on primary and secondary outcome measures. Results No intervention effects were found on children’s body composition. Analyses of secondary outcomes showed positive short-term intervention effects on children’s soft-drink consumption and parental responsibility regarding physical activity, encouragement to eat, psychological control, and efficacy and satisfaction with parenting. Longer-term intervention effects were found on parent’s report of children’s time spent on sedentary behavior and playing outside, parental monitoring food intake, and responsibility regarding nutrition. Conclusion Although the Lifestyle Triple P intervention showed

Enhancing Security of Double Random Phase Encoding Based on Random S-Box

Science.gov (United States)

Girija, R.; Singh, Hukum

2018-06-01

In this paper, we propose a novel asymmetric cryptosystem for double random phase encoding (DRPE) using random S-Box. While utilising S-Box separately is not reliable and DRPE does not support non-linearity, so, our system unites the effectiveness of S-Box with an asymmetric system of DRPE (through Fourier transform). The uniqueness of proposed cryptosystem lies on employing high sensitivity dynamic S-Box for our DRPE system. The randomness and scalability achieved due to applied technique is an additional feature of the proposed solution. The firmness of random S-Box is investigated in terms of performance parameters such as non-linearity, strict avalanche criterion, bit independence criterion, linear and differential approximation probabilities etc. S-Boxes convey nonlinearity to cryptosystems which is a significant parameter and very essential for DRPE. The strength of proposed cryptosystem has been analysed using various parameters such as MSE, PSNR, correlation coefficient analysis, noise analysis, SVD analysis, etc. Experimental results are conferred in detail to exhibit proposed cryptosystem is highly secure.

Effects of music therapy on self- and experienced stigma in patients on an acute care psychiatric unit: a randomized three group effectiveness study.

Science.gov (United States)

Silverman, Michael J

2013-10-01

Stigma is a major social barrier that can restrict access to and willingness to seek psychiatric care. Psychiatric consumers may use secrecy and withdrawal in an attempt to cope with stigma. The purpose of this study was to determine the effects of music therapy on self- and experienced stigma in acute care psychiatric inpatients using a randomized design with wait-list control. Participants (N=83) were randomly assigned by cluster to one of three single-session group-based conditions: music therapy, education, or wait-list control. Participants in the music therapy and education conditions completed only posttests while participants in the wait-list control condition completed only pretests. The music therapy condition was a group songwriting intervention wherein participants composed lyrics for "the stigma blues." Results indicated significant differences in measures of discrimination (experienced stigma), disclosure (self-stigma), and total stigma between participants in the music therapy condition and participants in the wait-list control condition. From the results of this randomized controlled investigation, music therapy may be an engaging and effective psychosocial technique to treat stigma. Limitations, suggestions for future research, and implications for clinical practice and psychiatric music therapy research are provided. © 2013.

Effect of tranexamic acid on gross hematuria: A pilot randomized clinical trial study.

Science.gov (United States)

Moharamzadeh, Payman; Ojaghihaghighi, Seyedhossein; Amjadi, Mohsen; Rahmani, Farzad; Farjamnia, Arezoo

2017-12-01

Local forms of the tranexamic acid have been effective in treating many haemorrhagic cases. So that the aim of the current study is to assess the effectiveness of local tranexamic acid in controlling painless hematuria in patients referred to the emergency department. This is a randomized, double-blind clinical trial study, which was conducted on 50 patients with complaints of painless lower urinary tract bleeding during June 2014 and August 2015. The patients were randomly divided into two groups of 25 people each, one group receiving tranexamic acid and the other given a placebo. During bladder irrigation, local tranexamic acid and the placebo were injected into the bladder via Foley catheter. Patients were examined over 24h in terms of the amount of normal saline serum used for irrigation, level of hemoglobin, and blood in urine. In this study it was observed that consumption of tranexamic acid significantly decreased the volume of used serum for bladder irrigation (P=0.041) and the microscopic status of urine decreased significantly in terms of the hematuria after 24h (P=0.026). However, the rate of packed cell transfusion and drop in hemoglobin levels showed no significant difference in both groups of patients (P˃0.05). The results of this study showed that tranexamic acid could significantly reduce the volume of required serum for bladder irrigation to clear urine, but it had no significant effect on the drop in serum hemoglobin levels. Copyright © 2017 Elsevier Inc. All rights reserved.

Effectiveness of Shockwave Treatment Combined With Eccentric Training for Patellar Tendinopathy : A Double-Blinded Randomized Study

NARCIS (Netherlands)

Thijs, Karin M; Zwerver, Johannes; Backx, Frank J G; Steeneken, Victor; Rayer, Stephan; Groenenboom, Petra; Moen, Maarten H

OBJECTIVE: To evaluate the effectiveness of a combined treatment of focused shockwave therapy (ESWT) and eccentric training compared with sham-shockwave therapy (placebo) and eccentric training in participants with patellar tendinopathy (PT) after 24 weeks. DESIGN: Randomized controlled trial.

Effectiveness of Shockwave Treatment Combined With Eccentric Training for Patellar Tendinopathy : A Double-Blinded Randomized Study

NARCIS (Netherlands)

Thijs, Karin M.; Zwerver, Johannes; Backx, Frank J. G.; Steeneken, Victor; Rayer, Stephan; Groenenboom, Petra; Moen, Maarten H.

2017-01-01

OBJECTIVE: To evaluate the effectiveness of a combined treatment of focused shockwave therapy (ESWT) and eccentric training compared with sham-shockwave therapy (placebo) and eccentric training in participants with patellar tendinopathy (PT) after 24 weeks. DESIGN: Randomized controlled trial.

Lactotripeptides Show No Effect on Human Blood Pressure: Results from a double-blind randomized controlled trial

NARCIS (Netherlands)

Engberink, M.F.; Schouten, E.G.; Kok, F.J.; Mierlo, van L.A.J.; Brouwer, I.A.; Geleijnse, J.M.

2008-01-01

Milk-derived peptides with ACE-inhibiting properties may have antihypertensive effects in humans. We conducted a randomized double-blind placebo-controlled trial to examine the blood pressure lowering potential of 2 ACE-inhibiting lactotripeptides, ie, Isoleucine-Proline-Proline and

Non-Stoichiometric SixN Metal-Oxide-Semiconductor Field-Effect Transistor for Compact Random Number Generator with 0.3 Mbit/s Generation Rate

Science.gov (United States)

Matsumoto, Mari; Ohba, Ryuji; Yasuda, Shin-ichi; Uchida, Ken; Tanamoto, Tetsufumi; Fujita, Shinobu

2008-08-01

The demand for random numbers for security applications is increasing. A conventional random number generator using thermal noise can generate unpredictable high-quality random numbers, but the circuit is extremely large because of large amplifier circuit for a small thermal signal. On the other hand, a pseudo-random number generator is small but the quality of randomness is bad. For a small circuit and a high quality of randomness, we purpose a non-stoichiometric SixN metal-oxide-semiconductor field-effect transistor (MOSFET) noise source device. This device generates a very large noise signal without an amplifier circuit. As a result, it is shown that, utilizing a SiN MOSFET, we can attain a compact random number generator with a high generation rate near 1 Mbit/s, which is suitable for almost all security applications.

Random processes in nuclear reactors

CERN Document Server

Williams, M M R

1974-01-01

Random Processes in Nuclear Reactors describes the problems that a nuclear engineer may meet which involve random fluctuations and sets out in detail how they may be interpreted in terms of various models of the reactor system. Chapters set out to discuss topics on the origins of random processes and sources; the general technique to zero-power problems and bring out the basic effect of fission, and fluctuations in the lifetime of neutrons, on the measured response; the interpretation of power reactor noise; and associated problems connected with mechanical, hydraulic and thermal noise sources

Effect of Reiki therapy on pain and anxiety in adults: an in-depth literature review of randomized trials with effect size calculations.

Science.gov (United States)

Thrane, Susan; Cohen, Susan M

2014-12-01

The objective of this study was to calculate the effect of Reiki therapy for pain and anxiety in randomized clinical trials. A systematic search of PubMed, ProQuest, Cochrane, PsychInfo, CINAHL, Web of Science, Global Health, and Medline databases was conducted using the search terms pain, anxiety, and Reiki. The Center for Reiki Research also was examined for articles. Studies that used randomization and a control or usual care group, used Reiki therapy in one arm of the study, were published in 2000 or later in peer-reviewed journals in English, and measured pain or anxiety were included. After removing duplicates, 49 articles were examined and 12 articles received full review. Seven studies met the inclusion criteria: four articles studied cancer patients, one examined post-surgical patients, and two analyzed community dwelling older adults. Effect sizes were calculated for all studies using Cohen's d statistic. Effect sizes for within group differences ranged from d = 0.24 for decrease in anxiety in women undergoing breast biopsy to d = 2.08 for decreased pain in community dwelling adults. The between group differences ranged from d = 0.32 for decrease of pain in a Reiki versus rest intervention for cancer patients to d = 4.5 for decrease in pain in community dwelling adults. Although the number of studies is limited, based on the size Cohen's d statistics calculated in this review, there is evidence to suggest that Reiki therapy may be effective for pain and anxiety. Continued research using Reiki therapy with larger sample sizes, consistently randomized groups, and standardized treatment protocols is recommended. Copyright © 2014 American Society for Pain Management Nursing. Published by Elsevier Inc. All rights reserved.

Random broadcast on random geometric graphs

Energy Technology Data Exchange (ETDEWEB)

Bradonjic, Milan [Los Alamos National Laboratory; Elsasser, Robert [UNIV OF PADERBORN; Friedrich, Tobias [ICSI/BERKELEY; Sauerwald, Tomas [ICSI/BERKELEY

2009-01-01

In this work, we consider the random broadcast time on random geometric graphs (RGGs). The classic random broadcast model, also known as push algorithm, is defined as: starting with one informed node, in each succeeding round every informed node chooses one of its neighbors uniformly at random and informs it. We consider the random broadcast time on RGGs, when with high probability: (i) RGG is connected, (ii) when there exists the giant component in RGG. We show that the random broadcast time is bounded by {Omicron}({radical} n + diam(component)), where diam(component) is a diameter of the entire graph, or the giant component, for the regimes (i), or (ii), respectively. In other words, for both regimes, we derive the broadcast time to be {Theta}(diam(G)), which is asymptotically optimal.

Effect of cryotherapy after elbow arthrolysis: a prospective, single-blinded, randomized controlled study.

Science.gov (United States)

Yu, Shi-yang; Chen, Shuai; Yan, He-de; Fan, Cun-yi

2015-01-01

To investigate the effect of cryotherapy after elbow arthrolysis on elbow pain, blood loss, analgesic consumption, range of motion, and long-term elbow function. Prospective, single-blinded, randomized controlled study. University hospital. Patients (N=59; 27 women, 32 men) who received elbow arthrolysis. Patients were randomly assigned into a cryotherapy group (n=31, cryotherapy plus standard care) or a control group (n=28, standard care). Elbow pain at rest and in motion were measured using a visual analog scale (VAS) on postoperative day (POD) 1 to POD 7 and at 2 weeks and 3 months after surgery. Blood loss and analgesic consumption were recorded postoperatively. Elbow range of motion (ROM) was measured before surgery and on POD 1, POD 7, and 3 months after surgery. The Mayo Elbow Performance Score (MEPS) was evaluated preoperatively and 3 months postoperatively. VAS scores were significantly lower in the cryotherapy group during the first 7 PODs, both at rest and in motion (Pcryotherapy group than the control group for pain relief (P.05). Cryotherapy is effective in relieving pain and reducing analgesic consumption for patients received elbow arthrolysis. The application of cryotherapy will not affect blood loss, ROM, or elbow function. Copyright © 2015 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Random reward priming is task-contingent: The robustness of the 1-trial reward priming effect

Directory of Open Access Journals (Sweden)

Árni Gunnar Ásgeirsson

2014-04-01

Full Text Available Consistent financial reward of particular features influences the allocation of visual attention in many ways. More surprising are 1-trial reward priming effects on attention where reward schedules are random and reward on one trial influences attentional allocation on the next. Those findings are thought to reflect that rewarded features become more salient than unrewarded ones on the subsequent trial. Here we attempt to conceptually replicate this effect, testing its generalizability. In three versions of an analogous paradigm to the additional singleton paradigm involving singleton search for a Gabor patch of odd spatial frequency we found no evidence of reward priming, while we only partially replicate the reward priming in the exact original paradigm tested by Hickey and colleagues. The results cast doubt on the proposal that random reward enhances salience, suggested in the original papers, and highlight the need for a more nuanced account. In many other paradigms reward effects have been found to progress gradually, becoming stronger as they build up, and we argue that for robust reward priming, reward schedules need to be more consistent than in the original 1-trial reward priming paradigm.

Effect of psychiatric consultation models in primary care. A systematic review and meta-analysis of randomized clinical trials

NARCIS (Netherlands)

van der Feltz-Cornelis, Christina M.; Van Os, Titus W. D. P.; Van Marwijk, Harm W. J.; Leentjens, Albert F. G.

Objective: Psychiatric consultation in primary care is meant to enhance and improve treatment for mental disorder in that setting. An estimate of the effect for different conditions as well as identification of particularly effective elements is needed. Methods: Database search for randomized

Effects of hormone therapy on brain structure: A randomized controlled trial.

Science.gov (United States)

Kantarci, Kejal; Tosakulwong, Nirubol; Lesnick, Timothy G; Zuk, Samantha M; Gunter, Jeffrey L; Gleason, Carey E; Wharton, Whitney; Dowling, N Maritza; Vemuri, Prashanthi; Senjem, Matthew L; Shuster, Lynne T; Bailey, Kent R; Rocca, Walter A; Jack, Clifford R; Asthana, Sanjay; Miller, Virginia M

2016-08-30

To investigate the effects of hormone therapy on brain structure in a randomized, double-blinded, placebo-controlled trial in recently postmenopausal women. Participants (aged 42-56 years, within 5-36 months past menopause) in the Kronos Early Estrogen Prevention Study were randomized to (1) 0.45 mg/d oral conjugated equine estrogens (CEE), (2) 50 μg/d transdermal 17β-estradiol, or (3) placebo pills and patch for 48 months. Oral progesterone (200 mg/d) was given to active treatment groups for 12 days each month. MRI and cognitive testing were performed in a subset of participants at baseline, and at 18, 36, and 48 months of randomization (n = 95). Changes in whole brain, ventricular, and white matter hyperintensity volumes, and in global cognitive function, were measured. Higher rates of ventricular expansion were observed in both the CEE and the 17β-estradiol groups compared to placebo; however, the difference was significant only in the CEE group (p = 0.01). Rates of ventricular expansion correlated with rates of decrease in brain volume (r = -0.58; p ≤ 0.001) and with rates of increase in white matter hyperintensity volume (r = 0.27; p = 0.01) after adjusting for age. The changes were not different between the CEE and 17β-estradiol groups for any of the MRI measures. The change in global cognitive function was not different across the groups. Ventricular volumes increased to a greater extent in recently menopausal women who received CEE compared to placebo but without changes in cognitive performance. Because the sample size was small and the follow-up limited to 4 years, the findings should be interpreted with caution and need confirmation. This study provides Class I evidence that brain ventricular volume increased to a greater extent in recently menopausal women who received oral CEE compared to placebo. © 2016 American Academy of Neurology.

The Effect of Music Therapy in Patients with Huntington's Disease: A Randomized Controlled Trial.

Science.gov (United States)

van Bruggen-Rufi, Monique C H; Vink, Annemieke C; Wolterbeek, Ron; Achterberg, Wilco P; Roos, Raymund A C

2017-01-01

Music therapy may have beneficial effects on improving communication and expressive skills in patients with Huntington's disease (HD). Most studies are, however, small observational studies and methodologically limited. Therefore we conducted a multi-center randomized controlled trial. To determine the efficacy of music therapy in comparison with recreational therapy in improving quality of life of patients with advanced Huntington's disease by means of improving communication. Sixty-three HD-patients with a Total Functional Capacity (TFC) score of ≤7, admitted to four long-term care facilities in The Netherlands, were randomized to receive either group music therapy or group recreational therapy in 16 weekly sessions. They were assessed at baseline, after 8, 16 and 28 weeks using the Behaviour Observation Scale for Huntington (BOSH) and the Problem Behaviour Assessment-short version (PBA-s). A linear mixed model with repeated measures was used to compare the scores between the two groups. Group music therapy offered once weekly for 16 weeks to patients with Huntington's disease had no additional beneficial effect on communication or behavior compared to group recreational therapy. This was the first study to assess the effect of group music therapy on HD patients in the advanced stages of the disease. The beneficial effects of music therapy, recorded in many, mainly qualitative case reports and studies, could not be confirmed with the design (i.e. group therapy vs individual therapy) and outcome measures that have been used in the present study. A comprehensive process-evaluation alongside the present effect evaluation is therefore performed.

Random number generation and creativity.

Science.gov (United States)

Bains, William

2008-01-01

A previous paper suggested that humans can generate genuinely random numbers. I tested this hypothesis by repeating the experiment with a larger number of highly numerate subjects, asking them to call out a sequence of digits selected from 0 through 9. The resulting sequences were substantially non-random, with an excess of sequential pairs of numbers and a deficit of repeats of the same number, in line with previous literature. However, the previous literature suggests that humans generate random numbers with substantial conscious effort, and distractions which reduce that effort reduce the randomness of the numbers. I reduced my subjects' concentration by asking them to call out in another language, and with alcohol - neither affected the randomness of their responses. This suggests that the ability to generate random numbers is a 'basic' function of the human mind, even if those numbers are not mathematically 'random'. I hypothesise that there is a 'creativity' mechanism, while not truly random, provides novelty as part of the mind's defence against closed programming loops, and that testing for the effects seen here in people more or less familiar with numbers or with spontaneous creativity could identify more features of this process. It is possible that training to perform better at simple random generation tasks could help to increase creativity, through training people to reduce the conscious mind's suppression of the 'spontaneous', creative response to new questions.

Effects of Vitamin D Supplementation on Bone Turnover Markers: A Randomized Controlled Trial

Directory of Open Access Journals (Sweden)

Verena Schwetz

2017-04-01

Full Text Available Bone turnover markers (BTMs are used to evaluate bone health together with bone mineral density and fracture assessment. Vitamin D supplementation is widely used to prevent and treat musculoskeletal diseases but existing data on vitamin D effects on markers of bone resorption and formation are inconsistent. We therefore examined the effects of vitamin D supplementation on bone-specific alkaline phosphatase (bALP, osteocalcin (OC, C-terminal telopeptide (CTX, and procollagen type 1 N-terminal propeptide (P1NP. This is a post-hoc analysis of the Styrian Vitamin D Hypertension Trial, a single-center, double-blind, randomized, placebo-controlled trial (RCT performed at the Medical University of Graz, Austria (2011–2014. Two hundred individuals with arterial hypertension and 25-hydroxyvitamin D (25[OH]D levels <75 nmol/L were randomized to 2800 IU of vitamin D daily or placebo for eight weeks. One hundred ninety-seven participants (60.2 ± 11.1 years; 47% women were included in this analysis. Vitamin D had no significant effect on bALP (mean treatment effect (MTE 0.013, 95% CI −0.029 to 0.056 µg/L; p = 0.533, CTX (MTE 0.024, 95% CI −0.163 to 0.210 ng/mL, p = 0.802, OC (MTE 0.020, 95% CI −0.062 to 0.103 ng/mL, p = 0.626, or P1NP (MTE −0.021, 95% CI −0.099 to 0.057 ng/mL, p = 0.597. Analyzing patients with 25(OHD levels <50 nmol/L separately (n = 74 left results largely unchanged. In hypertensive patients with low 25(OHD levels, we observed no significant effect of vitamin D supplementation for eight weeks on BTMs.

Clinical effects of probiotics containing Bacillus species on gingivitis: a pilot randomized controlled trial.

Science.gov (United States)

Alkaya, B; Laleman, I; Keceli, S; Ozcelik, O; Cenk Haytac, M; Teughels, W

2017-06-01

Lactobacillus spp. and bifidobacteria are the most frequently used probiotics in oral health research. However, although probiotic effects have been suggested for other genera, such as bacilli, no trials are available to describe the effect of bacilli probiotics on gingivitis in humans. The aim of the present study was to evaluate the clinical effects of a bacilli-containing toothpaste, a mouthrinse and a toothbrush cleaner versus a placebo in patients with generalized gingivitis. In this double-blind placebo-controlled randomized clinical trial, nonsmoking, systemically healthy patients with generalized gingivitis were included. They used a placebo or an experimental probiotic Bacillus subtilis-, Bacillus megaterium- and Bacillus pumulus-containing toothpaste, mouthrinse and toothbrush cleaner for 8 wk. Primary outcome measures of interest were plaque and gingivitis index, and the secondary outcome measures were pocket probing depth and bleeding on probing. Twenty male and 20 female patients were randomized over the two groups. All participants could be included in the final analysis. Although plaque and gingivitis indices were significantly reduced after 8 wk, no intergroup differences could be found at any time point. Also, for the secondary outcome measure, intragroup but no intergroup differences could be detected. No harm or unintended effects were reported by the patients after using the study products. This study did not show any statistically significant differences between a placebo and a bacilli-containing toothpaste, mouthrinse and toothbrush cleaner on gingivitis parameters. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Perturbation theory for the effective diffusion constant in a medium of random scatterers

International Nuclear Information System (INIS)

Dean, D S; Drummond, I T; Horgan, R R; Lefevre, A

2004-01-01

We develop perturbation theory and physically motivated resummations of the perturbation theory for the problem of a tracer particle diffusing in a random medium. The random medium contains point scatterers of density ρ uniformly distributed throughout the material. The tracer is a Langevin particle subjected to the quenched random force generated by the scatterers. Via our perturbative analysis, we determine when the random potential can be approximated by a Gaussian random potential. We also develop a self-similar renormalization group approach based on thinning out the scatterers; this scheme is similar to that used with success for diffusion in Gaussian random potentials and agrees with known exact results. To assess the accuracy of this approximation scheme, its predictions are confronted with results obtained by numerical simulation

The effect of random dopant fluctuation on threshold voltage and drain current variation in junctionless nanotransistors

International Nuclear Information System (INIS)

Rezapour, Arash; Rezapour, Pegah

2015-01-01

We investigate the effect of dopant random fluctuation on threshold voltage and drain current variation in a two-gate nanoscale transistor. We used a quantum-corrected technology computer aided design simulation to run the simulation (10000 randomizations). With this simulation, we could study the effects of varying the dimensions (length and width), and thicknesses of oxide and dopant factors of a transistor on the threshold voltage and drain current in subthreshold region (off) and overthreshold (on). It was found that in the subthreshold region the variability of the drain current and threshold voltage is relatively fixed while in the overthreshold region the variability of the threshold voltage and drain current decreases remarkably, despite the slight reduction of gate voltage diffusion (compared with that of the subthreshold). These results have been interpreted by using previously reported models for threshold current variability, load displacement, and simple analytical calculations. Scaling analysis shows that the variability of the characteristics of this semiconductor increases as the effects of the short channel increases. Therefore, with a slight increase of length and a reduction of width, oxide thickness, and dopant factor, we could correct the effect of the short channel. (paper)

Topics in random walks in random environment

International Nuclear Information System (INIS)

Sznitman, A.-S.

2004-01-01

Over the last twenty-five years random motions in random media have been intensively investigated and some new general methods and paradigms have by now emerged. Random walks in random environment constitute one of the canonical models of the field. However in dimension bigger than one they are still poorly understood and many of the basic issues remain to this day unresolved. The present series of lectures attempt to give an account of the progresses which have been made over the last few years, especially in the study of multi-dimensional random walks in random environment with ballistic behavior. (author)

Effect of intradermal human recombinant copper-zinc superoxide dismutase on random pattern flaps in rats.

Science.gov (United States)

Schein, Ophir; Westreich, Melvyn; Shalom, Avshalom

2013-09-01

Studies have focused on enhancing flap viability using superoxide dismutase (SOD), but only a few used SOD from human origin, and most gave the compound systemically. We evaluated the ability of SOD to improve random skin flap survival using human recombinant copper-zinc superoxide dismutase (Hr-CuZnSOD) in variable doses, injected intradermally into the flap. Seventy male Sprague Dawley rats were randomly assigned into 4 groups. Cephalic random pattern flaps were elevated on their backs and intradermal injections of different dosages of Hr-CuZnSOD were given 15 minutes before surgery. Flap survival was evaluated by fluorescein fluorescence. Analysis of variance (ANOVA) and t test statistical analyses were performed. Flap survival in all treated groups was significantly better than in the controls. The beneficial effect of HR-CuZnSOD on flap survival is attained when it is given intradermally into the flap tissue. Theoretically, Hr-CuZnSOD delivered with local anesthetics used in flap elevation may be a valuable clinical tool. Copyright © 2012 Wiley Periodicals, Inc.

Is ginger effective for the treatment of irritable bowel syndrome? A double blind randomized controlled pilot trial.

Science.gov (United States)

van Tilburg, Miranda A L; Palsson, Olafur S; Ringel, Yehuda; Whitehead, William E

2014-02-01

Ginger is one of the most commonly used herbal medicines for irritable bowel syndrome (IBS) but no data exists about its effectiveness. Double blind randomized controlled trial. University of North Carolina, Chapel Hill, North Carolina, USA. Forty-five IBS patients were randomly assigned to three groups: placebo, 1g of ginger, and 2g of ginger daily for 28 days. The IBS severity scale (IBS-SS) was administered, as well as adequate relief of symptoms scale. A responder was defined as having at least 25% reduction in IBS-SS post-treatment. There were 57.1% responders to placebo, 46.7% to 1g and 33.3% to 2g of ginger. Adequate relief was reported by 53.3% on placebo and 53.3% in both ginger groups combined. Side effects were mild and reported by 35.7% in the placebo and 16.7% in the ginger groups. This double blind randomized controlled pilot study suggests ginger is well tolerated but did not perform better than placebo. Larger trials are needed before any definitive conclusions can be drawn. Copyright © 2014 Elsevier Ltd. All rights reserved.

Adverse effects of homeopathy, what do we know? A systematic review and meta-analysis of randomized controlled trials.

Science.gov (United States)

Stub, Trine; Musial, Frauke; Kristoffersen, Agnete A; Alræk, Terje; Liu, Jianping

2016-06-01

Homeopathy is a popular treatment modality among patient, however there is sparse research about adverse effects of homeopathy. A concept unique for homeopathy, is homeopathic aggravation that is understood as a transient worsening of the patients' symptoms before an expected improvement occurs. From a risk perspective it is vital that a distinction between homeopathic aggravations and adverse effects is established. There is a lack of systematic information on how frequent adverse effects and homeopathic aggravations are reported in studies. Therefore, a systematic review and meta-analysis were performed. Sixteen electronic databases were searched for Randomized Controlled Trials (RCTs). The searches were limited from the year 1995 to January 2011. Forty-one RCTs, with a total of 6.055 participants were included. A subtotal of 39 studies was included in the additional meta-analysis. A total of 28 trials (68%) reported adverse effects and five trials (12%) reported homeopathic aggravations. The meta-analysis (including six subgroup comparisons) demonstrated that no significant difference was found between homeopathy and control with OR 0.99, 95% CI 0.86-1.14, I(2)=54%. More than two third of the adverse effects were classified as grade 1 (68%) and two third were classified as grade 2 (25%) and grade 3 (6%) according to the Common Terminology Criteria for Adverse Effects. Homeopathic aggravation was classified as grade 1 (98%) and grade 3 (2%), suggesting that homeopathic aggravations were reported to be less severe than adverse effects. The methodological quality according to a method recommended in the Cochrane handbook for RCTs, was high. Adverse effects including the concept of homeopathic aggravations are commonly reported in trials. The meta-analysis demonstrated that the proportion of patients experiencing adverse effects to be similar for patients randomized to homeopathic treatment compared to patients randomized to placebo and conventional medicine

Effect of flashlight guidance on manual ventilation performance in cardiopulmonary resuscitation: A randomized controlled simulation study.

Science.gov (United States)

Kim, Ji Hoon; Beom, Jin Ho; You, Je Sung; Cho, Junho; Min, In Kyung; Chung, Hyun Soo

2018-01-01

Several auditory-based feedback devices have been developed to improve the quality of ventilation performance during cardiopulmonary resuscitation (CPR), but their effectiveness has not been proven in actual CPR situations. In the present study, we investigated the effectiveness of visual flashlight guidance in maintaining high-quality ventilation performance. We conducted a simulation-based, randomized, parallel trial including 121 senior medical students. All participants were randomized to perform ventilation during 2 minutes of CPR with or without flashlight guidance. For each participant, we measured mean ventilation rate as a primary outcome and ventilation volume, inspiration velocity, and ventilation interval as secondary outcomes using a computerized device system. Mean ventilation rate did not significantly differ between flashlight guidance and control groups (P = 0.159), but participants in the flashlight guidance group exhibited significantly less variation in ventilation rate than participants in the control group (Pguidance group. Our results demonstrate that flashlight guidance is effective in maintaining a constant ventilation rate and interval. If confirmed by further studies in clinical practice, flashlight guidance could be expected to improve the quality of ventilation performed during CPR.

Does sucralfate reduce early side effects of pelvic radiation? A double-blind randomized trial.

Science.gov (United States)

Stellamans, Karin; Lievens, Yolande; Lambin, Philippe; Van den Weyngaert, Danielle; Van den Bogaert, Walter; Scalliet, Pierre; Hutsebaut, Liesbeth; Haustermans, Karin

2002-11-01

STUDY AND METHODS: A double-blind placebo-controlled study randomized 108 patients to investigate the effect of sucralfate on gastrointestinal side effects of pelvic radiation. Overall, pelvic radiation with the administered doses and fields and performed according to nowadays technical standards, was well tolerated. Comparison of the mean scores and the peak reactions for radiotherapy discomfort, diarrhoea and number of stools per day in the 80 evaluable patients showed no statistically significant difference between sucralfate and placebo. Based on these results, the use of sucralfate can not be recommended as standard practice.

Does sucralfate reduce early side effects of pelvic radiation? A double-blind randomized trial

International Nuclear Information System (INIS)

Stellamans, Karin; Lievens, Yolande; Lambin, Philippe; Van den Weyngaert, Danielle; Van den Bogaert, Walter; Scalliet, Pierre; Hutsebaut, Liesbeth; Haustermans, Karin

2002-01-01

Study and methods: A double-blind placebo-controlled study randomized 108 patients to investigate the effect of sucralfate on gastrointestinal side effects of pelvic radiation. Results: Overall, pelvic radiation with the administered doses and fields and performed according to nowadays technical standards, was well tolerated. Comparison of the mean scores and the peak reactions for radiotherapy discomfort, diarrhoea and number of stools per day in the 80 evaluable patients showed no statistically significant difference between sucralfate and placebo. Conclusion: Based on these results, the use of sucralfate can not be recommended as standard practice

Twice random, once mixed: applying mixed models to simultaneously analyze random effects of language and participants.

Science.gov (United States)

Janssen, Dirk P

2012-03-01

Psychologists, psycholinguists, and other researchers using language stimuli have been struggling for more than 30 years with the problem of how to analyze experimental data that contain two crossed random effects (items and participants). The classical analysis of variance does not apply; alternatives have been proposed but have failed to catch on, and a statistically unsatisfactory procedure of using two approximations (known as F(1) and F(2)) has become the standard. A simple and elegant solution using mixed model analysis has been available for 15 years, and recent improvements in statistical software have made mixed models analysis widely available. The aim of this article is to increase the use of mixed models by giving a concise practical introduction and by giving clear directions for undertaking the analysis in the most popular statistical packages. The article also introduces the DJMIXED: add-on package for SPSS, which makes entering the models and reporting their results as straightforward as possible.

Source-Independent Quantum Random Number Generation

Directory of Open Access Journals (Sweden)

Zhu Cao

2016-02-01

Full Text Available Quantum random number generators can provide genuine randomness by appealing to the fundamental principles of quantum mechanics. In general, a physical generator contains two parts—a randomness source and its readout. The source is essential to the quality of the resulting random numbers; hence, it needs to be carefully calibrated and modeled to achieve information-theoretical provable randomness. However, in practice, the source is a complicated physical system, such as a light source or an atomic ensemble, and any deviations in the real-life implementation from the theoretical model may affect the randomness of the output. To close this gap, we propose a source-independent scheme for quantum random number generation in which output randomness can be certified, even when the source is uncharacterized and untrusted. In our randomness analysis, we make no assumptions about the dimension of the source. For instance, multiphoton emissions are allowed in optical implementations. Our analysis takes into account the finite-key effect with the composable security definition. In the limit of large data size, the length of the input random seed is exponentially small compared to that of the output random bit. In addition, by modifying a quantum key distribution system, we experimentally demonstrate our scheme and achieve a randomness generation rate of over 5×10^{3}  bit/s.

The effect of adaptive versus static practicing on student learning - evidence from a randomized field experiment

NARCIS (Netherlands)

van Klaveren, Chris; Vonk, Sebastiaan; Cornelisz, Ilja

2017-01-01

Schools and governments are increasingly investing in adaptive practice software. To date, the evidence whether adaptivity improves learning outcomes is limited and mixed. A large-scale randomized control trial is conducted in Dutch secondary schools to evaluate the effectiveness of an adaptive

Using the symptom monitor in a randomized controlled trial: the effect on symptom prevalence and severity

NARCIS (Netherlands)

Hoekstra, Johanna; de Vos, Rien; van Duijn, Nico P.; Schadé, Egbert; Bindels, Patrick J. E.

2006-01-01

This randomized controlled trial investigated the effect of reporting physical symptoms by using a systematic symptom monitoring instrument, the Symptom Monitor, on symptom prevalence and severity among patients with cancer in the palliative phase. The overall objective was to achieve symptom relief

Renal Hemodynamic Effects of Serelaxin in Patients With Chronic Heart Failure A Randomized, Placebo-Controlled Study

NARCIS (Netherlands)

Voors, Adriaan A.; Dahlke, Marion; Meyer, Sven; Stepinska, Janina; Gottlieb, Stephen S.; Jones, Andrew; Zhang, Yiming; Laurent, Didier; Slart, Riemer H. J. A.; Navis, Gerjan J.

2014-01-01

Background-Serelaxin is a promising therapy for acute heart failure. The renal hemodynamic effects of serelaxin in patients with chronic heart failure are unknown. Methods and Results-In this double-blind, randomized, placebo-controlled, multicenter study, patients with New York Heart Association

Effect of short-term estrogen therapy on endothelial function: a double-blinded, randomized, controlled trial.

Science.gov (United States)

Hurtado, R; Celani, M; Geber, S

2016-10-01

To evaluate the effect of short-term hormone replacement therapy with 0.625 mg conjugated estrogens daily on endothelial function of healthy postmenopausal women, using flow-mediated dilation (FMD) of the brachial artery. We performed a double-blinded, randomized, controlled trial over 3 years. Randomization was performed using computer-generated sorting. All participants were blinded to the use of conjugated equine estrogens (CEE) or placebo and FMD was assessed by a blinded examiner, before and after 28 days of medication. A total of 64 healthy postmenopausal women were selected and randomly assigned into two groups of treatment: 0.625 mg of CEE or placebo. FMD values were statistically different between the groups (p = 0.025): the group receiving CEE showed a FMD value of 0.011 compared to the placebo group (FMD = -0.082). The two groups were additionally evaluated for homogeneity through the Shapiro-Wilk test in respect to variables that could interfere with endothelial function such as age (p = 0.729), body mass index (p = 0.891), and time since menopause (p = 0.724). Other variables were excluded during selection of the participants such as chronic vascular conditions, smoking, and sedentary lifestyle. Our results demonstrate that the administration of 0.625 mg CEE for 28 days is effective in improving vascular nitric oxide-dependent dilation assessed by FMD of the brachial artery in postmenopausal women. NCT01482416.

Perceptions of randomized security schedules.

Science.gov (United States)

Scurich, Nicholas; John, Richard S

2014-04-01

Security of infrastructure is a major concern. Traditional security schedules are unable to provide omnipresent coverage; consequently, adversaries can exploit predictable vulnerabilities to their advantage. Randomized security schedules, which randomly deploy security measures, overcome these limitations, but public perceptions of such schedules have not been examined. In this experiment, participants were asked to make a choice between attending a venue that employed a traditional (i.e., search everyone) or a random (i.e., a probability of being searched) security schedule. The absolute probability of detecting contraband was manipulated (i.e., 1/10, 1/4, 1/2) but equivalent between the two schedule types. In general, participants were indifferent to either security schedule, regardless of the probability of detection. The randomized schedule was deemed more convenient, but the traditional schedule was considered fairer and safer. There were no differences between traditional and random schedule in terms of perceived effectiveness or deterrence. Policy implications for the implementation and utilization of randomized schedules are discussed. © 2013 Society for Risk Analysis.

Bell inequalities for random fields

Energy Technology Data Exchange (ETDEWEB)

Morgan, Peter [Physics Department, Yale University, CT 06520 (United States)

2006-06-09

The assumptions required for the derivation of Bell inequalities are not satisfied for random field models in which there are any thermal or quantum fluctuations, in contrast to the general satisfaction of the assumptions for classical two point particle models. Classical random field models that explicitly include the effects of quantum fluctuations on measurement are possible for experiments that violate Bell inequalities.

Bell inequalities for random fields

OpenAIRE

Morgan, Peter

2004-01-01

The assumptions required for the derivation of Bell inequalities are not usually satisfied for random fields in which there are any thermal or quantum fluctuations, in contrast to the general satisfaction of the assumptions for classical two point particle models. Classical random field models that explicitly include the effects of quantum fluctuations on measurement are possible for experiments that violate Bell inequalities.

The effectiveness of core stabilization exercise in adolescent idiopathic scoliosis: A randomized controlled trial.

Science.gov (United States)

Gür, Gözde; Ayhan, Cigdem; Yakut, Yavuz

2017-06-01

Core stabilization training is used to improve postural balance in musculoskeletal problems. The purpose of this study was to investigate the effectiveness of stabilization training in adolescent idiopathic scoliosis. A randomized controlled trial, pretest-posttest design. In total, 25 subjects with adolescent idiopathic scoliosis were randomly divided into two groups: stabilization group ( n = 12) and control group ( n = 13). The stabilization group received core stabilization in addition to traditional rehabilitation, and the control group received traditional rehabilitation for 10 weeks. Assessment included Cobb's angle on radiograph, apical vertebral rotation in Adam's test, trunk asymmetry (Posterior Trunk Symmetry Index), cosmetic trunk deformity (Trunk Appearance Perception Scale), and quality of life (Scoliosis Research Society-22 questionnaire). Inter-group comparisons showed significantly greater improvements in the mean change in lumbar apical vertebral rotation degree and the pain domain of Scoliosis Research Society-22 in the stabilization group than those in the control group ( p adolescent idiopathic scoliosis. Clinical relevance Stabilization exercises are more effective in reducing rotation deformity and pain than traditional exercises in the conservative rehabilitation of adolescent idiopathic scoliosis. These improvements suggest that stabilization training should be added to rehabilitation programs in adolescent idiopathic scoliosis.

Exploring Mechanisms of Effective Teacher Coaching: A Tale of Two Cohorts From a Randomized Experiment

Science.gov (United States)

Blazar, David; Kraft, Matthew A.

2015-01-01

Although previous research has shown that teacher coaching can improve teaching practices and student achievement, little is known about specific features of effective coaching programs. We estimate the impact of MATCH Teacher Coaching (MTC) on a range of teacher practices using a blocked randomized trial and explore how changes in the coaching…

Influence of random setup error on dose distribution

International Nuclear Information System (INIS)

Zhai Zhenyu

2008-01-01

Objective: To investigate the influence of random setup error on dose distribution in radiotherapy and determine the margin from ITV to PTV. Methods: A random sample approach was used to simulate the fields position in target coordinate system. Cumulative effect of random setup error was the sum of dose distributions of all individual treatment fractions. Study of 100 cumulative effects might get shift sizes of 90% dose point position. Margins from ITV to PTV caused by random setup error were chosen by 95% probability. Spearman's correlation was used to analyze the influence of each factor. Results: The average shift sizes of 90% dose point position was 0.62, 1.84, 3.13, 4.78, 6.34 and 8.03 mm if random setup error was 1,2,3,4,5 and 6 mm,respectively. Univariate analysis showed the size of margin was associated only by the size of random setup error. Conclusions: Margin of ITV to PTV is 1.2 times random setup error for head-and-neck cancer and 1.5 times for thoracic and abdominal cancer. Field size, energy and target depth, unlike random setup error, have no relation with the size of the margin. (authors)

Long-term effect of physical activity counseling on mobility limitation among older people: a randomized controlled study

DEFF Research Database (Denmark)

Mänty, Minna Regina; Heinonen, Ari; Leinonen, Raija

2009-01-01

counseling-induced benefits persist after cessation of the intervention. METHODS: In a 2-year, single-blinded, randomized controlled study, 632 sedentary participants aged 75-81 years were randomly assigned into the intervention (n = 318) or control (n = 314) group. The intervention group received a single......BACKGROUND: Physical activity counseling increases physical activity among older people, but its effectiveness on mobility, that is, maintaining the ability to move independently, is unknown. We studied the effect of physical activity counseling on mobility among older people and evaluated whether...... individualized physical activity counseling session with a supportive telephone contact every 4 months for 2 years. The outcome measures-perceived difficulty in advanced (walking 2 km) and basic (walking 0.5 km) mobility-were gathered semiannually during the intervention and the 1.5-year postintervention follow...

Effects of sertindole on cognition in clozapine-treated schizophrenia patients - a double-blinded, randomized, placebo-controlled trial

DEFF Research Database (Denmark)

Nielsen, R E; Levander, S; Nielsen, Jimmi

Nielsen RE, Levander S, Thode D, Nielsen J. Effects of sertindole on cognition in clozapine-treated schizophrenia patients. Objective:  To assess the cognitive effects of sertindole augmentation in clozapine-treated patients diagnosed with schizophrenia. Cognition is secondary outcome of the trial....... Method:  A 12-week, double-blinded, randomized, placebo-controlled, augmentation study of patients treated with clozapine. Participants were randomized 1:1 to receive 16 mg of sertindole or placebo as adjunctive treatment to clozapine. Results:  Participants displayed substantial cognitive deficits......, ranging from 1.6 standard deviation below norms at baseline to more than three standard deviations on tests of response readiness and focused attention. There were no significant differences between sertindole augmentation and placebo groups at study end. Correlation analysis of Positive and Negative...

Random thermal stress in concrete containments

International Nuclear Information System (INIS)

Singh, M.P.; Heller, R.A.

1980-01-01

Currently, the overly conservative thermal design forces are obtained on the basis of simplified assumptions made about the temperature gradient across the containment wall. Using the method presented in this paper, a more rational and better estimate of the design forces can be obtained. Herein, the outside temperature is considered to consist of a constant mean on which yearly and daily harmonic changes plus a randomly varying part are superimposed. The random part is modeled as a stationary random process. To obtain the stresses due to random and harmonic temperatures, the complex frequency response function approach has been used. Numerical results obtained for a typical containment show that the higher frequency temperature variations, though of large magnitude, induce relatively small forces in a containment. Therefore, in a containment design, a rational separation of more effective, slowly varying temperatures, such as seasonal cycle from less effective but more frequently occuring daily and hourly changes, is desirable to obtain rational design forces. 7 refs

Analyzing indirect effects in cluster randomized trials. The effect of estimation method, number of groups and group sizes on accuracy and power.

Directory of Open Access Journals (Sweden)

Joop eHox

2014-02-01

Full Text Available Cluster randomized trials assess the effect of an intervention that is carried out at the group or cluster level. Ajzen’s theory of planned behaviour is often used to model the effect of the intervention as an indirect effect mediated in turn by attitude, norms and behavioural intention. Structural equation modelling (SEM is the technique of choice to estimate indirect effects and their significance. However, this is a large sample technique, and its application in a cluster randomized trial assumes a relatively large number of clusters. In practice, the number of clusters in these studies tends to be relatively small, e.g. much less than fifty. This study uses simulation methods to find the lowest number of clusters needed when multilevel SEM is used to estimate the indirect effect. Maximum likelihood estimation is compared to Bayesian analysis, with the central quality criteria being accuracy of the point estimate and the confidence interval. We also investigate the power of the test for the indirect effect. We conclude that Bayes estimation works well with much smaller cluster level sample sizes such as 20 cases than maximum likelihood estimation; although the bias is larger the coverage is much better. When only 5 to 10 clusters are available per treatment condition even with Bayesian estimation problems occur.

Can Ashi points stimulation have specific effects on shoulder pain? A systematic review of randomized controlled trials.

Science.gov (United States)

Wang, Kang-Feng; Zhang, Li-Juan; Lu, Feng; Lu, Yong-Hui; Yang, Chuan-Hua

2016-06-01

To provide an evidence-based overview regarding the efficacy of Ashi points stimulation for the treatment of shoulder pain. A comprehensive search [PubMed, Chinese Biomedical Literature Database, China National Knowledge Infrastructure (CNKI), Chongqing Weipu Database for Chinese Technical Periodicals (VIP) and Wanfang Database] was conducted to identify randomized or quasi-randomized controlled trials that evaluated the effectiveness of Ashi points stimulation for shoulder pain compared with conventional treatment. The methodological quality of the included studies was assessed using the Cochrane risk of bias tool. RevMan 5.0 was used for data synthesis. Nine trials were included. Seven studies assessed the effectiveness of Ashi points stimulation on response rate compared with conventional acupuncture. Their results suggested significant effect in favour of Ashi points stimulation [odds ratio (OR): 5.89, 95% confidence interval (CI): 2.97 to 11.67, Pfirm conclusion could not be reached until further studies of high quality are available.

Effect of guided relaxation and imagery on falls self-efficacy: a randomized controlled trial.

Science.gov (United States)

Kim, Bang Hyun; Newton, Roberta A; Sachs, Michael L; Glutting, Joseph J; Glanz, Karen

2012-06-01

To examine the effects of guided relaxation and imagery (GRI) on improvement in falls self-efficacy in older adults who report having a fear of falling. Randomized, controlled trial with allocation to GRI or guided relaxation with music of choice. General community. Ninety-one men and women aged 60 to 92. Participants were randomized to listen to a GRI audio compact disk (intervention group) or a guided relaxation audio compact disk and music of choice (control group) twice a week for 6 weeks for 10 minutes per session. Primary outcome measure was the Short Falls Efficacy Scale-International (FES-I). Secondary outcome measures were the Leisure Time Exercise Questionnaire (LTEQ) and the Timed Up and Go (TUG) mobility test. GRI participants reported greater improvements on the Short FES-I (P = .002) and LTEQ (P = .001) scores and shorter time on the TUG (P = .002) than the guided relaxation and music-of-choice group. GRI was more effective at increasing falls self-efficacy and self-reported leisure time exercise and reducing times on a simple mobility test than was guided relaxation with music of choice. GRI is an effective, simple, low-cost tool for older adults to improve falls self-efficacy and leisure time exercise behaviors. © 2012, Copyright the Authors Journal compilation © 2012, The American Geriatrics Society.

Evaluating the Flipped Classroom: A Randomized Controlled Trial

Science.gov (United States)

Wozny, Nathan; Balser, Cary; Ives, Drew

2018-01-01

Despite recent interest in flipped classrooms, rigorous research evaluating their effectiveness is sparse. In this study, the authors implement a randomized controlled trial to evaluate the effect of a flipped classroom technique relative to a traditional lecture in an introductory undergraduate econometrics course. Random assignment enables the…

Random walks and polygons in tight confinement

International Nuclear Information System (INIS)

Diao, Y; Ernst, C; Ziegler, U

2014-01-01

We discuss the effect of confinement on the topology and geometry of tightly confined random walks and polygons. Here the walks and polygons are confined in a sphere of radius R ≥ 1/2 and the polygons are equilateral with n edges of unit length. We illustrate numerically that for a fixed length of random polygons the knotting probability increases to one as the radius decreases to 1/2. We also demonstrate that for random polygons (walks) the curvature increases to πn (π(n – 1)) as the radius approaches 1/2 and that the torsion decreases to ≈ πn/3 (≈ π(n – 1)/3). In addition we show the effect of length and confinement on the average crossing number of a random polygon

Effectiveness of pharmaceutical care at discharge in the emergency department: study protocol of a randomized controlled trial.

Science.gov (United States)

Kuhmmer, Regina; Lima, Karine Margarites; Ribeiro, Rodrigo Antonini; Hammes, Luciano Serpa; Bastos, Gisele Alsina Nader; Cotta de Souza, Maria Claudia Schardosim; Polanczyk, Carisi Anne; Soares Rollin, Guilherme Alcides Flores; Caon, Suhelen; Guterres, Cátia Moreira; Araújo Leite, Leni Everson; Delabary, Tássia Scholante; Falavigna, Maicon

2015-02-25

Patient education on pharmacological therapy may increase medication adherence and decrease hospitalizations. Our aim is to evaluate the effectiveness of pharmaceutical care at emergency department discharge in patients with hypertension and/or diabetes. This is a randomized controlled trial. Participants will be recruited from a public emergency department at Restinga district in Porto Alegre, southern Brazil. A total of 380 patients will be randomly assigned into 2 groups at the moment of emergency department discharge after receiving medical orientations: an intervention group, consisting of a structured individual counseling session by a pharmacist in addition to written orientations, or a control group, consisting only of written information about the disease. Outcomes will be assessed in an ambulatory visit 2 months after the randomization. The primary outcome is the proportion of patients with high medication adherence assessed using the Morisky-Green Test and the Brief Medication Questionnaire. The secondary outcomes are reduction of blood pressure, glycated hemoglobin, fasting plasma glucose, quality of life and number of visits to the emergency department. Pharmaceutical care interventions have shown to be feasible and effective in increasing medication adherence in both hospital outpatient and community pharmacy settings. However, there have been no previous assessments of the effectiveness of pharmacy care interventions initiated in patients discharged from emergency departments. Our hypothesis is that pharmaceutical counseling is also effective in this population. ClinicalTrials.gov registration number: NCT01978925 (11 November 2013) and Brazilian Registry of Clinical Trials U1111-1149-8922 (5 November 2013).

Magnetic field line random walk in non-axisymmetric turbulence

International Nuclear Information System (INIS)

Tautz, R.C.; Lerche, I.

2011-01-01

Including a random component of a magnetic field parallel to an ambient field introduces a mean perpendicular motion to the average field line. This effect is normally not discussed because one customarily chooses at the outset to ignore such a field component in discussing random walk and diffusion of field lines. A discussion of the basic effect is given, indicating that any random magnetic field with a non-zero helicity will lead to such a non-zero perpendicular mean motion. Several exact analytic illustrations are given of the effect as well as a simple numerical illustration. -- Highlights: → For magnetic field line random walk all magnetic field components are important. → Non-vanishing magnetic helicity leads to mean perpendicular motion. → Analytically exact stream functions illustrate that the novel transverse effect exists.

Effect of etanercept in polymyalgia rheumatica: a randomized controlled trial

DEFF Research Database (Denmark)

Kreiner, Frederik; Galbo, Henrik

2010-01-01

To elucidate in polymyalgia rheumatica (PMR) the role of tumor necrosis factor (TNF) α and the therapeutic potential of blockade with soluble TNF-α receptor, we carried out the first randomized controlled trial with etanercept in PMR.......To elucidate in polymyalgia rheumatica (PMR) the role of tumor necrosis factor (TNF) α and the therapeutic potential of blockade with soluble TNF-α receptor, we carried out the first randomized controlled trial with etanercept in PMR....

Early intervention in panic: randomized controlled trial and cost-effectiveness analysis

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van Balkom Anton

2008-11-01

Full Text Available Abstract Background Panic disorder (PD is a common, severe and persistent mental disorder, associated with a high degree of distress and occupational and social disability. A substantial proportion of the population experiences subthreshold and mild PD and is at risk of developing a chronic PD. A promising intervention, aimed at preventing panic disorder onset and reducing panic symptoms, is the 'Don't Panic' course. It consists of eight sessions of two hours each. The purpose of this study is to evaluate the effectiveness of this early intervention – based on cognitive behavioural principles – on the reduction of panic disorder symptomatology. We predict that the experimental condition show superior clinical and economic outcomes relative to a waitlisted control group. Methods/design A pragmatic, pre-post, two-group, multi-site, randomized controlled trial of the intervention will be conducted with a naturalistic follow-up at six months in the intervention group. The participants are recruited from the general population and are randomized to the intervention or a waitlist control group. The intervention is offered by community mental health centres. Included are people over 18 years of age with subthreshold or mild panic disorder, defined as having symptoms of PD falling below the cut-off of 13 on the Panic Disorder Severity Scale-Self Report (PDSS-SR. Primary outcomes are panic disorder and panic symptoms. Secondary outcomes are symptoms of agoraphobia, anxiety, cognitive aspects of panic disorder, depressive symptoms, mastery, health-related quality of life, and cost-effectiveness. We will examine the following variables as potential mediators: cognitive aspects of panic disorder, symptoms of agoraphobia, anxiety and mastery. Potential moderating variables are: socio-demographic characteristics, panic disorder, agoraphobia, treatment credibility and mastery. Discussion This study was designed to evaluate the (cost effectiveness of an

Effectiveness of an intervention to reduce sickness absence in patients with emotional distress or minor mental disorders: a randomized controlled effectiveness trial.

NARCIS (Netherlands)

Brouwers, E.P.M.; Tiemens, B.G.; Terluin, B.; Verhaak, P.F.M.

2006-01-01

OBJECTIVE: The purpose of this study was to evaluate the effectiveness of an activating intervention designed to reduce sick leave duration in patients with emotional distress or minor mental disorders. METHOD: In a 1.5-year randomized controlled trial, 194 patients with minor mental disorders

Effect of an educational toolkit on quality of care: a pragmatic cluster randomized trial.

Science.gov (United States)

Shah, Baiju R; Bhattacharyya, Onil; Yu, Catherine H Y; Mamdani, Muhammad M; Parsons, Janet A; Straus, Sharon E; Zwarenstein, Merrick

2014-02-01

Printed educational materials for clinician education are one of the most commonly used approaches for quality improvement. The objective of this pragmatic cluster randomized trial was to evaluate the effectiveness of an educational toolkit focusing on cardiovascular disease screening and risk reduction in people with diabetes. All 933,789 people aged ≥40 years with diagnosed diabetes in Ontario, Canada were studied using population-level administrative databases, with additional clinical outcome data collected from a random sample of 1,592 high risk patients. Family practices were randomly assigned to receive the educational toolkit in June 2009 (intervention group) or May 2010 (control group). The primary outcome in the administrative data study, death or non-fatal myocardial infarction, occurred in 11,736 (2.5%) patients in the intervention group and 11,536 (2.5%) in the control group (p = 0.77). The primary outcome in the clinical data study, use of a statin, occurred in 700 (88.1%) patients in the intervention group and 725 (90.1%) in the control group (p = 0.26). Pre-specified secondary outcomes, including other clinical events, processes of care, and measures of risk factor control, were also not improved by the intervention. A limitation is the high baseline rate of statin prescribing in this population. The educational toolkit did not improve quality of care or cardiovascular outcomes in a population with diabetes. Despite being relatively easy and inexpensive to implement, printed educational materials were not effective. The study highlights the need for a rigorous and scientifically based approach to the development, dissemination, and evaluation of quality improvement interventions. http://www.ClinicalTrials.gov NCT01411865 and NCT01026688.

[Intel random number generator-based true random number generator].

Science.gov (United States)

Huang, Feng; Shen, Hong

2004-09-01

To establish a true random number generator on the basis of certain Intel chips. The random numbers were acquired by programming using Microsoft Visual C++ 6.0 via register reading from the random number generator (RNG) unit of an Intel 815 chipset-based computer with Intel Security Driver (ISD). We tested the generator with 500 random numbers in NIST FIPS 140-1 and X(2) R-Squared test, and the result showed that the random number it generated satisfied the demand of independence and uniform distribution. We also compared the random numbers generated by Intel RNG-based true random number generator and those from the random number table statistically, by using the same amount of 7500 random numbers in the same value domain, which showed that the SD, SE and CV of Intel RNG-based random number generator were less than those of the random number table. The result of u test of two CVs revealed no significant difference between the two methods. Intel RNG-based random number generator can produce high-quality random numbers with good independence and uniform distribution, and solves some problems with random number table in acquisition of the random numbers.

Pip and pop : Non-spatial auditory signals improve spatial visual search

NARCIS (Netherlands)

Burg, E. van der; Olivers, C.N.L.; Bronkhorst, A.W.; Theeuwes, J.

2008-01-01

Searching for an object within a cluttered, continuously changing environment can be a very time-consuming process. The authors show that a simple auditory pip drastically decreases search times for a synchronized visual object that is normally very difficult to find. This effect occurs even though

Effective Recruitment of Schools for Randomized Clinical Trials: Role of School Nurses.

Science.gov (United States)

Petosa, R L; Smith, L

2017-01-01

In school settings, nurses lead efforts to improve the student health and well-being to support academic success. Nurses are guided by evidenced-based practice and data to inform care decisions. The randomized controlled trial (RCT) is considered the gold standard of scientific rigor for clinical trials. RCTs are critical to the development of evidence-based health promotion programs in schools. The purpose of this article is to present practical solutions to implementing principles of randomization to RCT trials conducted in school settings. Randomization is a powerful sampling method used to build internal and external validity. The school's daily organization and educational mission provide several barriers to randomization. Based on the authors' experience in conducting school-based RCTs, they offer a host of practical solutions to working with schools to successfully implement randomization procedures. Nurses play a critical role in implementing RCTs in schools to promote rigorous science in support of evidence-based practice.

Moving from Efficacy to Effectiveness in Cognitive Behavioral Therapy for Psychosis: A Randomized Clinical Practice Trial

Science.gov (United States)

Lincoln, Tania M.; Ziegler, Michael; Mehl, Stephanie; Kesting, Marie-Luise; Lullmann, Eva; Westermann, Stefan; Rief, Winfried

2012-01-01

Objective: Randomized controlled trials have attested the efficacy of cognitive behavioral therapy (CBT) in reducing psychotic symptoms. Now, studies are needed to investigate its effectiveness in routine clinical practice settings. Method: Eighty patients with schizophrenia spectrum disorders who were seeking outpatient treatment were randomized…

Unanticipated Effect of a Randomized Peer Network Intervention on Depressive Symptoms among Young Methamphetamine Users in Thailand

Science.gov (United States)

German, D.; Sutcliffe, C. G.; Sirirojn, B.; Sherman, S. G.; Latkin, C. A.; Aramrattana, A.; Celentano, D. D.

2012-01-01

We examined the effect on depressive symptoms of a peer network-oriented intervention effective in reducing sexual risk behavior and methamphetamine (MA) use. Current Thai MA users aged 18-25 years and their drug and/or sex network members enrolled in a randomized controlled trial with 4 follow-ups over 12 months. A total of 415 index participants…

Cost-effective degradation test plan for a nonlinear random-coefficients model

International Nuclear Information System (INIS)

Kim, Seong-Joon; Bae, Suk Joo

2013-01-01

The determination of requisite sample size and the inspection schedule considering both testing cost and accuracy has been an important issue in the degradation test. This paper proposes a cost-effective degradation test plan in the context of a nonlinear random-coefficients model, while meeting some precision constraints for failure-time distribution. We introduce a precision measure to quantify the information losses incurred by reducing testing resources. The precision measure is incorporated into time-varying cost functions to reflect real circumstances. We apply a hybrid genetic algorithm to general cost optimization problem with reasonable constraints on the level of testing precision in order to determine a cost-effective inspection scheme. The proposed method is applied to the degradation data of plasma display panels (PDPs) following a bi-exponential degradation model. Finally, sensitivity analysis via simulation is provided to evaluate the robustness of the proposed degradation test plan.

Randomization tests

CERN Document Server

Edgington, Eugene

2007-01-01

Statistical Tests That Do Not Require Random Sampling Randomization Tests Numerical Examples Randomization Tests and Nonrandom Samples The Prevalence of Nonrandom Samples in Experiments The Irrelevance of Random Samples for the Typical Experiment Generalizing from Nonrandom Samples Intelligibility Respect for the Validity of Randomization Tests Versatility Practicality Precursors of Randomization Tests Other Applications of Permutation Tests Questions and Exercises Notes References Randomized Experiments Unique Benefits of Experiments Experimentation without Mani

Cognitive effects of calligraphy therapy for older people: a randomized controlled trial in Hong Kong

Directory of Open Access Journals (Sweden)

Kwok TCY

2011-10-01

Full Text Available Timothy CY Kwok1,2, Xue Bai1,3, Henry SR Kao4,5, Jessie CY Li1, Florence KY Ho11Jockey Club Centre for Positive Ageing; 2Department of Medicine and Therapeutics, The Chinese University of Hong Kong; 3Department of Social Work and Social Administration; 4Department of Psychology, The University of Hong Kong, Hong Kong; 5Department of Psychology, Fu Jen Catholic University, TaiwanBackground: This pilot study investigated the effects of calligraphy therapy on cognitive function in older Hong Kong Chinese people with mild cognitive impairment.Methods: A single-blind, randomized controlled trial was carried out in a sample of 31 adults aged 65 years or older with mild cognitive impairment. They were randomly assigned to receive either intensive calligraphy training led by a trained research assistant for eight weeks (calligraphy group, n = 14 or no calligraphy treatment (control group, n = 17. Participants' cognitive function was assessed by the Chinese version of the Mini-Mental State Examination (CMMSE before and after calligraphy treatment. Repeated measures analysis of variance and paired samples t-tests were used to analyze the data.Results: A significant interaction effect of time and intervention was detected [F (1, 29 = 9.11, P = 0.005, η2= 0.24]. The calligraphy group was found to have a prominent increase in CMMSE global score, and scores in the cognitive areas of orientation, attention, and calculation after two months (∆M = 2.36, P < 0.01, whereas their counterparts in the control group experienced a decline in CMMSE score (∆M = -0.41, P < 0.05.Conclusion: Calligraphy therapy was effective for enhancing cognitive function in older people with mild cognitive impairment and should be incorporated as part of routine programs in both community and residential care settings.Keywords: calligraphy therapy, Chinese elderly, mild cognitive impairment, cognitive function, randomized controlled trial

Postural stability effects of random vibration at the feet of construction workers in simulated elevation.

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Simeonov, P; Hsiao, H; Powers, J; Ammons, D; Kau, T; Amendola, A

2011-07-01

The risk of falls from height on a construction site increases under conditions which degrade workers' postural control. At elevation, workers depend heavily on sensory information from their feet to maintain balance. The study tested two hypotheses: "sensory enhancement"--sub-sensory (undetectable) random mechanical vibrations at the plantar surface of the feet can improve worker's balance at elevation; and "sensory suppression"--supra-sensory (detectable) random mechanical vibrations can have a degrading effect on balance in the same experimental settings. Six young (age 20-35) and six aging (age 45-60) construction workers were tested while standing in standard and semi-tandem postures on instrumented gel insoles. The insoles applied sub- or supra-sensory levels of random mechanical vibrations to the feet. The tests were conducted in a surround-screen virtual reality system, which simulated a narrow plank at elevation on a construction site. Upper body kinematics was assessed with a motion-measurement system. Postural stability effects were evaluated by conventional and statistical mechanics sway measures, as well as trunk angular displacement parameters. Analysis of variance did not confirm the "sensory enhancement" hypothesis, but provided evidence for the "sensory suppression" hypothesis. The supra-sensory vibration had a destabilizing effect, which was considerably stronger in the semi-tandem posture and affected most of the sway variables. Sensory suppression associated with elevated vibration levels on a construction site may increase the danger of losing balance. Construction workers at elevation, e.g., on a beam or narrow plank might be at increased risk of fall if they can detect vibrations under their feet. To reduce the possibility of losing balance, mechanical vibration to supporting structures used as walking/working surfaces should be minimized when performing construction tasks at elevation. Published by Elsevier Ltd.

Randomized Controlled Trials Evaluating Effect of Television Advertising on Food Intake in Children: Why Such a Sensitive Topic is Lacking Top-Level Evidence?

Science.gov (United States)

Gregori, Dario; Ballali, Simonetta; Vecchio, Maria Gabriella; Sciré, Antonella Silvia; Foltran, Francesca; Berchialla, Paola

2014-01-01

The aim of this study was to perform a systematic review of evidence coming from randomized controlled trials (RCT) aimed at assessing the effect of television advertising on food intake in children from 4 to 12 years old. Randomized controlled trials were searched in PubMed database and included if they assessed the effect of direct exposure to television food advertising over the actual energy intake of children. Seven studies out of 2166 fulfilled the inclusion criteria. The association between television advertising and energy intake is based on a very limited set of randomized researches lacking a solid ground of first-level evidence.

Effectiveness of strengthened stimulation during acupuncture for the treatment of Bell palsy: a randomized controlled trial.

Science.gov (United States)

Xu, Sha-bei; Huang, Bo; Zhang, Chen-yan; Du, Peng; Yuan, Qi; Bi, Gui-juan; Zhang, Gui-bin; Xie, Min-jie; Luo, Xiang; Huang, Guang-ying; Wang, Wei

2013-04-02

The traditional Chinese theory of acupuncture emphasizes that the intensity of acupuncture must reach a threshold to generate de qi, which is necessary to achieve the best therapeutic effect. De qi is an internal compound sensation of soreness, tingling, fullness, aching, cool, warmth and heaviness, and a radiating sensation at and around the acupoints. However, the notion that de qi must be achieved for maximum benefit has not been confirmed by modern scientific evidence. We performed a prospective multicentre randomized controlled trial involving patients with Bell palsy. Patients were randomly assigned to the de qi (n = 167) or control (n = 171) group. Both groups received acupuncture: in the de qi group, the needles were manipulated manually until de qi was reached, whereas in the control group, the needles were inserted without any manipulation. All patients received prednisone as a basic treatment. The primary outcome was facial nerve function at month 6. We also assessed disability and quality of life 6 months after randomization. After 6 months, patients in the de qi group had better facial function (adjusted odds ratio [OR] 4.16, 95% confidence interval [CI] 2.23-7.78), better disability assessment (differences of least squares means 9.80, 95% CI 6.29-13.30) and better quality of life (differences of least squares means 29.86, 95% CI 22.33-37.38). Logistic regression analysis showed a positive effect of the de qi score on facial-nerve function (adjusted OR 1.07, 95% CI 1.04-1.09). Among patients with Bell palsy, acupuncture with strong stimulation that elicited de qi had a greater therapeutic effect, and stronger intensity of de qi was associated with the better therapeutic effects. Clinicaltrials.gov no. NCT00685789.

Effects of joint mobilization on chronic ankle instability: a randomized controlled trial.

Science.gov (United States)

Cruz-Díaz, David; Lomas Vega, Rafael; Osuna-Pérez, Maria Catalina; Hita-Contreras, Fidel; Martínez-Amat, Antonio

2015-01-01

To evaluate the effects of joint mobilization, in which movement is applied to the ankle's dorsiflexion range of motion, on dynamic postural control and on the self-reported instability of patients with chronic ankle instability (CAI). A double-blind, placebo-controlled, randomized trial with repeated measures and a follow-up period. Ninety patients with a history of recurrent ankle sprain, self-reported instability, and a limited dorsiflexion range of motion, were randomly assigned to either the intervention group (Joint Mobilizations, 3 weeks, two sessions per week) the placebo group (Sham Mobilizations, same duration as joint mobilization) or the control group, with a 6 months follow-up. Dorsiflexion Range of Motion (DFROM), Star Excursion Balance Test (SEBT) and CAI Tool (CAIT) were outcome measures. A separate 3 × 4 mixed model analysis of variance was performed to examine the effect of treatment conditions and time, and intention-to-treat (ITT) analysis was applied to evaluate the effect of the independent variable. The application of joint mobilization resulted in better scores of DFROM, CAIT, and SEBTs in the intervention group when compared with the placebo or the control groups (p ankle DFROM, postural control, and self-reported instability. These results suggest that joint mobilization could be applied to patients with recurrent ankle sprain to help restore their functional stability. Implications for Rehabilitation Functional instability is a very common sequela in patients with CAI, resulting in reduced quality of living due to the limitations it imposes on daily life activities. The mobilization with movement technique presented by Mulligan, and based on the joint mobilization accompanied by active movement, appears as a valuable tool to be employed by physical therapists to restore ankle function after a recurrent ankle sprain history. ROM restriction, subjective feeling of instability and dynamic postural control are benefiting from the joint

Effectiveness of adjuvant occupational therapy in employees with depression: design of a randomized controlled trial

Directory of Open Access Journals (Sweden)

Hees Hiske L

2010-09-01

Full Text Available Abstract Background Major depressive disorder is among the medical conditions with the highest negative impact on work outcome. However, little is known regarding evidence-based interventions targeting the improvement of work outcomes in depressed employees. In this paper, the design of a randomized controlled trial is presented in order to evaluate the effectiveness of adjuvant occupational therapy in employees with depression. This occupational intervention is based on an earlier intervention, which was designed and proven effective by our research group, and is the only intervention to date that specifically targets work outcome in depressed employees. Methods/Design In a two-arm randomized controlled trial, a total of 117 participants are randomized to either 'care as usual' or ' care as usual' with the addition of occupational therapy. Patients included in the study are employees who are absent from work due to depression for at least 25% of their contract hours, and who have a possibility of returning to their own or a new job. The occupational intervention consists of six individual sessions, eight group sessions and a work-place visit over a 16-week period. By increasing exposure to the working environment, and by stimulating communication between employer and employee, the occupational intervention aims to enhance self-efficacy and the acquisition of more adaptive coping strategies. Assessments take place at baseline, and at 6, 12, and 18-month follow-ups. Primary outcome measure is work participation (hours of absenteeism and time until work resumption. Secondary outcome measures are work functioning, symptomatology, health-related quality of life, and neurocognitive functioning. In addition, cost-effectiveness is evaluated from a societal perspective. Finally, mechanisms of change (intermediate outcomes and potential patient-treatment matching variables are investigated. Discussion This study hopes to provide valuable knowledge

[Immediate analgesic effect of wrist-ankle acupuncture for acute lumbago: a randomized controlled trial].

Science.gov (United States)

Su, Jiang-tao; Zhou, Qing-hui; Li, Rui; Zhang, Jie; Li, Wei-hong; Wang, Qiong

2010-08-01

To assess the immediate analgesic effect of wrist-ankle acupuncture on acute lumbago and the relationship between the analgesic effect and the expectation of patients. A randomized, single-blind, sham-controlled trial was designed. Sixty cases of acute lumbago were randomly divided into two groups, 30 cases in each one. In observation group, wrist-ankle acupuncture was adopted to the Lower 5 and Lower 6 bilaterally, no requirement of Deqi (arrival of qi). In control group, sham acupuncture was adopted. The treatment was applied once in either group, with the needles retained for 30 min. The Short-form McGill Pain Questionnaire (SF-MPQ) and the Modified-Modified Schober (MMS) test were used to assess the motion related pain and the situation of spinal flexion in 3 min before treatment and 5 min, 10 min, 15 min, during treatment and 30 min (needle removed), respectively. The Expectation and Treatment Credibility Scale (ETCS) was applied to analyze the relationship between the expectation of patients and the analgesic effect. The adverse reaction was recorded. There were no statistically significant differences in SF-MPQ, MMS and ETCS before treatment between two groups (all P>0.05). In 5 min after needles insertion, the scores of the items in SF-MPQ in observation group were lower than those in control group (P0.05). No adverse reaction was reported. Wrist-ankle acupuncture can reduce acute lumbago immediately and significantly. The higher the expectation on the analgesic effect of wrist-ankle acupuncture the patients have, the better the analgesic effect will be. This therapy is highly safe in the treatment.

Therapeutic Effect of Virtual Reality on Post-Stroke Patients: Randomized Clinical Trial.

Science.gov (United States)

Pedreira da Fonseca, Erika; Ribeiro da Silva, Nildo Manoel; Pinto, Elen Beatriz

2017-01-01

The study aimed to check the therapeutic effect of virtual reality associated with conventional physiotherapy on gait balance and the occurrence of falls after a stroke. This was a randomized, blinded clinical trial conducted with post-stroke patients, randomized into two groups-treatment group and control group-and subjected to balance assessments by the Dynamic Gait Index and investigation of falls before and after 20 intervention sessions. Statistically significant difference was considered at P < .05. We selected 30 patients, but there were three segment losses, resulting in a total of 13 patients in the control group and 14 in the treatment group. There was an improvement in gait balance and reduced occurrence of falls in both groups. After intervention, the differences in gait balance in the control group (P = .047) and the reduction in the occurrence of falls in the treatment group (P = .049) were significant. However, in intergroup analysis, there was no difference in the two outcomes. Therapy with games was a useful tool for gait balance rehabilitation in post-stroke patients, with repercussions on the reduction of falls. Copyright © 2017 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Effects of a random spatial variation of the plasma density on the mode conversion in cold, unmagnetized, and stratified plasmas

Energy Technology Data Exchange (ETDEWEB)

Jung Yu, Dae [School of Space Research, Kyung Hee University, Yongin 446-701 (Korea, Republic of); Kim, Kihong [Department of Energy Systems Research, Ajou University, Suwon 443-749 (Korea, Republic of)

2013-12-15

We study the effects of a random spatial variation of the plasma density on the mode conversion of electromagnetic waves into electrostatic oscillations in cold, unmagnetized, and stratified plasmas. Using the invariant imbedding method, we calculate precisely the electromagnetic field distribution and the mode conversion coefficient, which is defined to be the fraction of the incident wave power converted into electrostatic oscillations, for the configuration where a numerically generated random density variation is added to the background linear density profile. We repeat similar calculations for a large number of random configurations and take an average of the results. We obtain a peculiar nonmonotonic dependence of the mode conversion coefficient on the strength of randomness. As the disorder increases from zero, the maximum value of the mode conversion coefficient decreases initially, then increases to a maximum, and finally decreases towards zero. The range of the incident angle in which mode conversion occurs increases monotonically as the disorder increases. We present numerical results suggesting that the decrease of mode conversion mainly results from the increased reflection due to the Anderson localization effect originating from disorder, whereas the increase of mode conversion of the intermediate disorder regime comes from the appearance of many resonance points and the enhanced tunneling between the resonance points and the cutoff point. We also find a very large local enhancement of the magnetic field intensity for particular random configurations. In order to obtain high mode conversion efficiency, it is desirable to restrict the randomness close to the resonance region.

Effects of a random spatial variation of the plasma density on the mode conversion in cold, unmagnetized, and stratified plasmas

International Nuclear Information System (INIS)

Jung Yu, Dae; Kim, Kihong

2013-01-01

We study the effects of a random spatial variation of the plasma density on the mode conversion of electromagnetic waves into electrostatic oscillations in cold, unmagnetized, and stratified plasmas. Using the invariant imbedding method, we calculate precisely the electromagnetic field distribution and the mode conversion coefficient, which is defined to be the fraction of the incident wave power converted into electrostatic oscillations, for the configuration where a numerically generated random density variation is added to the background linear density profile. We repeat similar calculations for a large number of random configurations and take an average of the results. We obtain a peculiar nonmonotonic dependence of the mode conversion coefficient on the strength of randomness. As the disorder increases from zero, the maximum value of the mode conversion coefficient decreases initially, then increases to a maximum, and finally decreases towards zero. The range of the incident angle in which mode conversion occurs increases monotonically as the disorder increases. We present numerical results suggesting that the decrease of mode conversion mainly results from the increased reflection due to the Anderson localization effect originating from disorder, whereas the increase of mode conversion of the intermediate disorder regime comes from the appearance of many resonance points and the enhanced tunneling between the resonance points and the cutoff point. We also find a very large local enhancement of the magnetic field intensity for particular random configurations. In order to obtain high mode conversion efficiency, it is desirable to restrict the randomness close to the resonance region

Effectiveness of oncogenetics training on general practitioners' consultation skills: a randomized controlled trial.

Science.gov (United States)

Houwink, Elisa J F; Muijtjens, Arno M M; van Teeffelen, Sarah R; Henneman, Lidewij; Rethans, Jan Joost; van der Jagt, Liesbeth E J; van Luijk, Scheltus J; Dinant, Geert Jan; van der Vleuten, Cees; Cornel, Martina C

2014-01-01

General practitioners are increasingly called upon to deliver genetic services and could play a key role in translating potentially life-saving advancements in oncogenetic technologies to patient care. If general practitioners are to make an effective contribution in this area, their genetics competencies need to be upgraded. The aim of this study was to investigate whether oncogenetics training for general practitioners improves their genetic consultation skills. In this pragmatic, blinded, randomized controlled trial, the intervention consisted of a 4-h training (December 2011 and April 2012), covering oncogenetic consultation skills (family history, familial risk assessment, and efficient referral), attitude (medical ethical issues), and clinical knowledge required in primary-care consultations. Outcomes were measured using observation checklists by unannounced standardized patients and self-reported questionnaires. Of 88 randomized general practitioners who initially agreed to participate, 56 completed all measurements. Key consultation skills significantly and substantially improved; regression coefficients after intervention were equivalent to 0.34 and 0.28 at 3-month follow-up, indicating a moderate effect size. Satisfaction and perceived applicability of newly learned skills were highly scored. The general practitioner-specific training proved to be a feasible, satisfactory, and clinically applicable method to improve oncogenetics consultation skills and could be used as an educational framework to inform future training activities with the ultimate aim of improving medical care.

Effects of Assertiveness Training and Expressive Writing on Acculturative Stress in International Students: A Randomized Trial

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Tavakoli, Shedeh; Lumley, Mark A.; Hijazi, Alaa M.; Slavin-Spenny, Olga M.; Parris, George P.

2009-01-01

International university students often experience acculturative stress, and culturally appropriate techniques to manage stress are needed. This randomized trial tested the effects of group assertiveness training, private expressive writing, their combination, and a wait-list control on the acculturative stress, affect, and health of 118…

Testing Mediators of Intervention Effects in Randomized Controlled Trials: An Evaluation of Three Depression Prevention Programs

Science.gov (United States)

Stice, Eric; Rohde, Paul; Seeley, John R.; Gau, Jeff M.

2010-01-01

Objective: Evaluate a new 5-step method for testing mediators hypothesized to account for the effects of depression prevention programs. Method: In this indicated prevention trial, at-risk teens with elevated depressive symptoms were randomized to a group cognitive-behavioral (CB) intervention, group supportive expressive intervention, CB…

The effects of a digital formative assessment tool on spelling achievement : Results of a randomized experiment

NARCIS (Netherlands)

Faber, Janke M.; Visscher, Adrie J.

2018-01-01

In this study, a randomized experimental design was used to examine the effects of a digital formative assessment tool on spelling achievement of third grade students (eight-to nine-years-olds). The sample consisted of 30 experimental schools (n = 619) and 39 control schools (n = 986). Experimental

The effect of feature-based attention on flanker interference processing: An fMRI-constrained source analysis.

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Siemann, Julia; Herrmann, Manfred; Galashan, Daniela

2018-01-25

The present study examined whether feature-based cueing affects early or late stages of flanker conflict processing using EEG and fMRI. Feature cues either directed participants' attention to the upcoming colour of the target or were neutral. Validity-specific modulations during interference processing were investigated using the N200 event-related potential (ERP) component and BOLD signal differences. Additionally, both data sets were integrated using an fMRI-constrained source analysis. Finally, the results were compared with a previous study in which spatial instead of feature-based cueing was applied to an otherwise identical flanker task. Feature-based and spatial attention recruited a common fronto-parietal network during conflict processing. Irrespective of attention type (feature-based; spatial), this network responded to focussed attention (valid cueing) as well as context updating (invalid cueing), hinting at domain-general mechanisms. However, spatially and non-spatially directed attention also demonstrated domain-specific activation patterns for conflict processing that were observable in distinct EEG and fMRI data patterns as well as in the respective source analyses. Conflict-specific activity in visual brain regions was comparable between both attention types. We assume that the distinction between spatially and non-spatially directed attention types primarily applies to temporal differences (domain-specific dynamics) between signals originating in the same brain regions (domain-general localization).

Clinical and neurobiological effects of aerobic exercise in dental phobia: A randomized controlled trial.

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Lindenberger, Brigitt L; Plag, Jens; Schumacher, Sarah; Gaudlitz, Katharina; Bischoff, Sophie; Bobbert, Thomas; Dimeo, Fernando; Petzold, Moritz B; Kirschbaum, Clemens; Dudás, Zsuzsa; Ströhle, Andreas

2017-11-01

Physical activity has shown to be effective in anxiety disorders. For specific phobia, no studies are available that systematically examined the effects of an aerobic exercise intervention on phobic fear within a randomized-controlled design. Therefore, we investigated the acute effect of a standardized aerobic training on clinical symptoms of dental phobia as well as on stress-related neurobiological markers. Within a crossover design, 30 patients with dental phobia (mean age: 34.1 years; mean score of the Dental Anxiety Scale: 18.8) underwent two minor dental interventions separated by 7 days. Dental treatment was performed after 30 min of physical activity at either 20% VO 2 max (control) or 70% VO 2 max (intervention), respectively. To control for habituation, patients were randomly assigned to one of the two conditions prior to the first intervention. Moreover, saliva samples were collected at five times in order to determine changes in salivary cortisol (sC) and alpha-amylase (sAA) due to treatment. In comparison to baseline, aerobic exercise within 70% VO 2 max significantly reduced clinical anxiety and sC concentrations before, during, and after the dental treatment. In contrast, the control condition led to decreased sAA levels at different time points of measurement. Habituation occurred at the second study day, independent of the order. Our study provides evidence for an effect of moderate-intense exercise on clinical symptoms and sC in patients with dental phobia. Therefore, acute aerobic exercise might be a simple and low-cost intervention to reduce disorder-specific phobic fear. © 2017 Wiley Periodicals, Inc.

Unexpected Effects of a System-Distributed Mobile Application in Maternity Care: A Randomized Controlled Trial.

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Ledford, Christy J W; Womack, Jasmyne J; Rider, Heather A; Seehusen, Angela B; Conner, Stephen J; Lauters, Rebecca A; Hodge, Joshua A

2018-06-01

As pregnant mothers increasingly engage in shared decision making regarding prenatal decisions, such as induction of labor, the patient's level of activation may influence pregnancy outcomes. One potential tool to increase patient activation in the clinical setting is mobile applications. However, research is limited in comparing mobile apps with other modalities of patient education and engagement tools. This study was designed to test the effectiveness of a mobile app as a replacement for a spiral notebook guide as a patient education and engagement tool in the prenatal clinical setting. This randomized controlled trial was conducted in the Women's Health Clinic and Family Health Clinic of three hospitals. Repeated-measures analysis of covariance was used to test intervention effects in the study sample of 205 patients. Mothers used a mobile app interface to more frequently record information about their pregnancy; however, across time, mothers using a mobile app reported a significant decrease in patient activation. The unexpected negative effects in the group of patients randomized to the mobile app prompt these authors to recommend that health systems pause before distributing their own version of mobile apps that may decrease patient activation. Mobile apps can be inherently empowering and engaging, but how a system encourages their use may ultimately determine their adoption and success.

Effects of a price increase on purchases of sugar sweetened beverages. Results from a randomized controlled trial.

Science.gov (United States)

Waterlander, Wilma Elzeline; Ni Mhurchu, Cliona; Steenhuis, Ingrid H M

2014-07-01

Sugar sweetened beverage (SSB) taxes are receiving increased political interest. However, there have been no experimental studies of the effects of price increases on SSBs or the effects on close substitutes such as diet drinks, alcohol or sugary snacks. Therefore, the aim of this study was to examine the effects of a price increase on SSBs on beverage and snack purchases using a randomized controlled design within a three-dimensional web-based supermarket. The trial contained two conditions: experimental condition with a 19% tax on SSBs (to reflect an increase in Dutch value added tax from 6% to 19%); and a control condition with regular prices. N = 102 participants were randomized and purchased groceries on a single occasion at a three-dimensional Virtual Supermarket. Data were analysed using independent t-tests and regression analysis. Results showed that participants in the price increase condition purchased significantly less SSBs than the control group (B = -.90; 95% CI = -1.70 to -.10 L per household per week). There were no significant effects on purchases in other beverage or snack food categories. This means that the higher VAT rate was effective in reducing SSB purchases and had no negative side-effects. Copyright © 2014. Published by Elsevier Ltd.

Treatment selection in a randomized clinical trial via covariate-specific treatment effect curves.

Science.gov (United States)

Ma, Yunbei; Zhou, Xiao-Hua

2017-02-01

For time-to-event data in a randomized clinical trial, we proposed two new methods for selecting an optimal treatment for a patient based on the covariate-specific treatment effect curve, which is used to represent the clinical utility of a predictive biomarker. To select an optimal treatment for a patient with a specific biomarker value, we proposed pointwise confidence intervals for each covariate-specific treatment effect curve and the difference between covariate-specific treatment effect curves of two treatments. Furthermore, to select an optimal treatment for a future biomarker-defined subpopulation of patients, we proposed confidence bands for each covariate-specific treatment effect curve and the difference between each pair of covariate-specific treatment effect curve over a fixed interval of biomarker values. We constructed the confidence bands based on a resampling technique. We also conducted simulation studies to evaluate finite-sample properties of the proposed estimation methods. Finally, we illustrated the application of the proposed method in a real-world data set.

Feasibility and preliminary effectiveness of ice therapy in patients with an acute tear in the gastrocnemius muscle: A pilot randomized controlled trial

NARCIS (Netherlands)

Prins, J.C.M.; Stubbe, J.H.; Meeteren, N.L.U. van; Scheffers, F.A.; Dongen, M.C.J.M. van

2011-01-01

Objective: To investigate the feasibility of a randomized controlled trial and the preliminary effectiveness of ice therapy in the acute phase of a gastrocnemius tear for the quality of functional recovery. Design: A pilot version of an intended prospective randomized controlled clinical trial was

Anti-depressive effectiveness of olanzapine, quetiapine, risperidone and ziprasidone: a pragmatic, randomized trial

Directory of Open Access Journals (Sweden)

Løberg Else-Marie

2011-08-01

Full Text Available Abstract Background Efficacy studies indicate anti-depressive effects of at least some second generation antipsychotics (SGAs. The Bergen Psychosis Project (BPP is a 24-month, pragmatic, industry-independent, randomized, head-to-head comparison of olanzapine, quetiapine, risperidone and ziprasidone in patients acutely admitted with psychosis. The aim of the study is to investigate whether differential anti-depressive effectiveness exists among SGAs in a clinically relevant sample of patients acutely admitted with psychosis. Methods Adult patients acutely admitted to an emergency ward for psychosis were randomized to olanzapine, quetiapine, risperidone or ziprasidone and followed for up to 2 years. Participants were assessed repeatedly using the Positive and Negative Syndrome Scale - Depression factor (PANSS-D and the Calgary Depression Scale for Schizophrenia (CDSS. Results A total of 226 patients were included. A significant time-effect showing a steady decline in depressive symptoms in all medication groups was demonstrated. There were no substantial differences among the SGAs in reducing the PANSS-D score or the CDSS sum score. Separate analyses of groups with CDSS sum scores > 6 or ≤6, respectively, reflecting degree of depressive morbidity, revealed essentially identical results to the primary analyses. There was a high correlation between the PANSS-D and the CDSS sum score (r = 0.77; p Conclusions There was no substantial difference in anti-depressive effectiveness among olanzapine, quetiapine, risperidone or ziprasidone in this clinically relevant sample of patients acutely admitted to hospital for symptoms of psychosis. Based on our findings we can make no recommendations concerning choice of any particular SGA for targeting symptoms of depression in a patient acutely admitted with psychosis. Trial Registration ClinicalTrials.gov ID; URL: http://www.clinicaltrials.gov/: NCT00932529

Effects of Vitex agnus and Flaxseed on cyclic mastalgia: A randomized controlled trial.

Science.gov (United States)

Mirghafourvand, Mojgan; Mohammad-Alizadeh-Charandabi, Sakineh; Ahmadpour, Parivash; Javadzadeh, Yousef

2016-02-01

Evidence on the effect of Vitex agnus and Flaxseed on cyclical mastalgia is not enough. This study aimed to assess the efficacy of V. agnus and Flaxseed on cyclical mastalgia. This randomized controlled trial was conducted on 159 women referred to health centers of Tabriz, Iran. Subjects were allocated into three groups (n=53 per group) using block randomization. Group I received 25g daily Flaxseed powder and placebo of V. agnus; group II received daily 3.2-4.8mg V. agnus tablet and placebo of Flaxseed and control group received both placebo. Nominal day breast pain was applied at baseline, first, and second month after the intervention. Data was analyzed using general linear model. There was no statistical significant difference between the three groups in terms of socio-demographic characteristics and baseline values. The breast pain improved significantly in both intervention groups during the first and second month after intervention. Mean NDBP score was significantly lower than that in the control group at the first month after the intervention in the Flaxseed [adjusted mean difference: -3.1 (95% CI: -4.2 to -2.0)] and V. agnus groups [-3.3 (-4.3 to -2.2)] and the second month after the intervention in Flaxseed [-7.0 (-8.1 to -5.9)] and V. agnus groups [-6.4 (-7.5 to -5.3)]. Flaxseed and V. agnus are effective in short-term period in decreasing cyclical mastalgia. However, further studies are needed to examine the long-term effectiveness and sustainability of the effects after stopping the treatment in order to decide whether these alternative treatments are suitable to treat mastalgia or not. Copyright © 2015 Elsevier Ltd. All rights reserved.

Project SUCCESS' Effects on Substance Use-Related Attitudes and Behaviors: A Randomized Controlled Trial in Alternative High Schools

Science.gov (United States)

Clark, Heddy Kovach; Ringwalt, Chris L.; Shamblen, Stephen R.; Hanley, Sean M.

2011-01-01

Using a randomized controlled effectiveness trial, we examined the effects of Project SUCCESS on a range of secondary outcomes, including the program's mediating variables. Project SUCCESS, which is based both on the Theory of Reasoned Action and on Cognitive Behavior Theory, is a school-based substance use prevention program that targets…

An Exponential Tilt Mixture Model for Time-to-Event Data to Evaluate Treatment Effect Heterogeneity in Randomized Clinical Trials.

Science.gov (United States)

Wang, Chi; Tan, Zhiqiang; Louis, Thomas A

2014-01-01

Evaluating the effect of a treatment on a time-to-event outcome is the focus of many randomized clinical trials. It is often observed that the treatment effect is heterogeneous, where only a subgroup of the patients may respond to the treatment due to some unknown mechanism such as genetic polymorphism. In this paper, we propose a semiparametric exponential tilt mixture model to estimate the proportion of patients who respond to the treatment and to assess the treatment effect. Our model is a natural extension of parametric mixture models to a semiparametric setting with a time-to-event outcome. We propose a nonparametric maximum likelihood estimation approach for inference and establish related asymptotic properties. Our method is illustrated by a randomized clinical trial on biodegradable polymer-delivered chemotherapy for malignant gliomas patients.

Moderating Effects of Parental Characteristics on the Effectiveness of a Theory of Mind Training for Children with Autism : A Randomized Controlled Trial

NARCIS (Netherlands)

de Veld, Danielle M J; Howlin, Patricia; Hoddenbach, Elske; Mulder, Fleur; Wolf, Imke; Koot, Hans M.; Lindauer, Ramón; Begeer, Sander

2017-01-01

This RCT investigated whether the effect of a Theory of Mind (ToM) intervention for children with ASD was moderated by parental education level and employment, family structure, and parental ASD. Children with autism aged 8–13 years (n = 136) were randomized over a waitlist control or treatment

Moderating Effects of Parental Characteristics on the Effectiveness of a Theory of Mind Training for Children with Autism: A Randomized Controlled Trial

NARCIS (Netherlands)

de Veld, Danielle M. J.; Howlin, Patricia; Hoddenbach, Elske; Mulder, Fleur; Wolf, Imke; Koot, Hans M.; Lindauer, Ramón; Begeer, Sander

2017-01-01

This RCT investigated whether the effect of a Theory of Mind (ToM) intervention for children with ASD was moderated by parental education level and employment, family structure, and parental ASD. Children with autism aged 8-13 years (n = 136) were randomized over a waitlist control or treatment

Results of a multicenter randomized controlled trial of the clinical effectiveness of schema therapy for personality disorders

NARCIS (Netherlands)

Bamelis, L.L.M.; Evers, S.M.A.A.; Spinhoven, P.; Arntz, A.

2014-01-01

Objective: The authors compared the effectiveness of 50 sessions of schema therapy with clarification-oriented psychotherapy and with treatment as usual among patients with cluster C, paranoid, histrionic, or narcissistic personality disorder. Method: A multicenter randomized controlled trial, with

Effect of tai chi versus aerobic exercise for fibromyalgia: comparative effectiveness randomized controlled trial

Science.gov (United States)

Schmid, Christopher H; Fielding, Roger A; Harvey, William F; Reid, Kieran F; Price, Lori Lyn; Driban, Jeffrey B; Kalish, Robert; Rones, Ramel; McAlindon, Timothy

2018-01-01

Abstract Objectives To determine the effectiveness of tai chi interventions compared with aerobic exercise, a current core standard treatment in patients with fibromyalgia, and to test whether the effectiveness of tai chi depends on its dosage or duration. Design Prospective, randomized, 52 week, single blind comparative effectiveness trial. Setting Urban tertiary care academic hospital in the United States between March 2012 and September 2016. Participants 226 adults with fibromyalgia (as defined by the American College of Rheumatology 1990 and 2010 criteria) were included in the intention to treat analyses: 151 were assigned to one of four tai chi groups and 75 to an aerobic exercise group. Interventions Participants were randomly assigned to either supervised aerobic exercise (24 weeks, twice weekly) or one of four classic Yang style supervised tai chi interventions (12 or 24 weeks, once or twice weekly). Participants were followed for 52 weeks. Adherence was rigorously encouraged in person and by telephone. Main outcome measures The primary outcome was change in the revised fibromyalgia impact questionnaire (FIQR) scores at 24 weeks compared with baseline. Secondary outcomes included changes of scores in patient’s global assessment, anxiety, depression, self efficacy, coping strategies, physical functional performance, functional limitation, sleep, and health related quality of life. Results FIQR scores improved in all five treatment groups, but the combined tai chi groups improved statistically significantly more than the aerobic exercise group in FIQR scores at 24 weeks (difference between groups=5.5 points, 95% confidence interval 0.6 to 10.4, P=0.03) and several secondary outcomes (patient’s global assessment=0.9 points, 0.3 to 1.4, P=0.005; anxiety=1.2 points, 0.3 to 2.1, P=0.006; self efficacy=1.0 points, 0.5 to 1.6, P=0.0004; and coping strategies, 2.6 points, 0.8 to 4.3, P=0.005). Tai chi treatment compared with aerobic exercise administered with

A randomized multifactorial intervention study for prevention of ischaemic heart disease (Inter99): the long-term effect on physical activity

DEFF Research Database (Denmark)

von Huth Smith, Lisa; Ladelund, Steen; Borch-Johnsen, Knut

2008-01-01

, group B, n=1,308) were invited for a health examination, an assessment of absolute risk of developing IHD, and an individualized lifestyle intervention. The participation rate was 52.5%. High-risk persons in group A were also offered diet/physical activity and/or smoking cessation group counselling....... High-risk persons in group B were referred to their GP. High-risk persons were re-counselled after 12 and 36 months. The control group (group C, n=5,264, response rate=61.3%) answered a mailed questionnaire. Data were analysed using longitudinal linear regression models with random effects. MAIN......AIM: To examine the effect of a randomized multiple risk factor intervention study for prevention of ischaemic heart disease (IHD) on the development in physical activity over a 36-month period. METHODS: Two random samples (high intensity intervention, group A, n=11,708; low intensity intervention...

A randomized multifactorial intervention study for prevention of ischaemic heart disease (Inter99): The long-term effect on physical activity

DEFF Research Database (Denmark)

Smith, L.V.H.; Ladelund, S.; Borch-Johnsen, K.

2008-01-01

, group B, n=1,308) were invited for a health examination, an assessment of absolute risk of developing IHD, and an individualized lifestyle intervention. The participation rate was 52.5%. High-risk persons in group A were also offered diet/physical activity and/or smoking cessation group counselling....... High-risk persons in group B were referred to their GP. High-risk persons were re-counselled after 12 and 36 months. The control group (group C, n=5,264, response rate=61.3%) answered a mailed questionnaire. Data were analysed using longitudinal linear regression models with random effects. MAIN......AIM: To examine the effect of a randomized multiple risk factor intervention study for prevention of ischaemic heart disease (IHD) on the development in physical activity over a 36-month period. METHODS: Two random samples (high intensity intervention, group A, n=11,708; low intensity intervention...

The effects of assertiveness training in patients with schizophrenia: a randomized, single-blind, controlled study.

Science.gov (United States)

Lee, Tso-Ying; Chang, Shih-Chin; Chu, Hsin; Yang, Chyn-Yng; Ou, Keng-Liang; Chung, Min-Huey; Chou, Kuei-Ru

2013-11-01

In this study, we investigated the effects of group assertiveness training on assertiveness, social anxiety and satisfaction with interpersonal communication among patients with chronic schizophrenia. Only limited studies highlighted the effectiveness of group assertiveness training among inpatients with schizophrenia. Given the lack of group assertiveness training among patients with schizophrenia, further development of programmes focusing on facilitating assertiveness, self-confidence and social skills among inpatients with chronic schizophrenia is needed. This study used a prospective, randomized, single-blinded, parallel-group design. This study employed a prospective, randomized, parallel-group design. Seventy-four patients were randomly assigned to experimental group receiving 12 sessions of assertiveness training, or a supportive control group. Data collection took place for the period of June 2009-July 2010. Among patients with chronic schizophrenia, assertiveness, levels of social anxiety and satisfaction with interpersonal communication significantly improved immediately after the intervention and at the 3-month follow-up in the intervention group. The results of a generalized estimating equation (GEE) indicated that: (1) assertiveness significantly improved from pre- to postintervention and was maintained until the follow-up; (2) anxiety regarding social interactions significantly decreased after assertiveness training; and (3) satisfaction with interpersonal communication slightly improved after the 12-session intervention and at the 3-month follow-up. Assertivenss training is a non-invasive and inexpensive therapy that appears to improve assertiveness, social anxiety and interpersonal communication among inpatients with chronic schizophrenia. These findings may provide a reference guide to clinical nurses for developing assertiveness-training protocols. © 2013 Blackwell Publishing Ltd.

Effect of Whey Supplementation on Circulating C-Reactive Protein: A Meta-Analysis of Randomized Controlled Trials

Science.gov (United States)

Zhou, Ling-Mei; Xu, Jia-Ying; Rao, Chun-Ping; Han, Shufen; Wan, Zhongxiao; Qin, Li-Qiang

2015-01-01

Whey supplementation is beneficial for human health, possibly by reducing the circulating C-reactive protein (CRP) level, a sensitive marker of inflammation. Thus, a meta-analysis of randomized controlled trials was conducted to evaluate their relationship. A systematic literature search was conducted in July, 2014, to identify eligible studies. Either a fixed-effects model or a random-effects model was used to calculate pooled effects. The meta-analysis results of nine trials showed a slight, but no significant, reduction of 0.42 mg/L (95% CI −0.96, 0.13) in CRP level with the supplementation of whey protein and its derivates. Relatively high heterogeneity across studies was observed. Subgroup analyses showed that whey significantly lowered CRP by 0.72 mg/L (95% CI −0.97, −0.47) among trials with a daily whey dose ≥20 g/day and by 0.67 mg/L (95% CI −1.21, −0.14) among trials with baseline CRP ≥3 mg/L. Meta-regression analysis revealed that the baseline CRP level was a potential effect modifier of whey supplementation in reducing CRP. In conclusion, our meta-analysis did not find sufficient evidence that whey and its derivates elicited a beneficial effect in reducing circulating CRP. However, they may significantly reduce CRP among participants with highly supplemental doses or increased baseline CRP levels. PMID:25671415

Hip-Hop to Health Jr. Randomized Effectiveness Trial

Science.gov (United States)

Kong, Angela; Buscemi, Joanna; Stolley, Melinda R.; Schiffer, Linda A.; Kim, Yoonsang; Braunschweig, Carol L.; Gomez-Perez, Sandra L.; Blumstein, Lara B.; Van Horn, Linda; Dyer, Alan R.; Fitzgibbon, Marian L.

2015-01-01

Introduction The preschool years provide a unique window of opportunity to intervene on obesity-related lifestyle risk factors during the formative years of a child’s life. The purpose of this study was to assess the impact of a preschool-based obesity prevention effectiveness trial at 1-year follow-up. Design RCT. Settings/participants Primarily African American children (aged 3–5 years, N=618) attending Head Start preschool programs administered by Chicago Public Schools. Methods Eighteen preschools were randomly assigned in 2007–2008 to receive either: (1) a 14-week teacher-delivered intervention focused on healthy lifestyle behaviors; or (2) a 14-week teacher-delivered general health curriculum (control group). Main outcome measures The primary outcome, BMI, was measured at baseline, post-intervention, and 1-year follow-up. Diet and screen time behaviors were also assessed at these time points. Multilevel mixed effects models were used to test for between-group differences. Data were analyzed in 2014. Results Significant between-group differences were observed in diet, but not in BMI z-score or screen time at 1-year follow-up. Diet differences favored the intervention arm over controls in overall diet quality (p=0.02) and in subcomponents of diet quality, as measured by the Healthy Eating Index-2005, and in fruit intake (servings/day, excludes juice) (p=0.02). Diet quality worsened more among controls than the intervention group at 1-year follow-up. Conclusions The adaptation of Hip-Hop to Health Jr. produced modest benefits in diet quality, but did not significantly impact weight gain trajectory. Not unlike other effectiveness trials, this real-world version delivered by Head Start teachers produced fewer benefits than the more rigorous efficacy trial. It is important to understand and build upon the lessons learned from these types of trials so that we can design, implement, and disseminate successful evidence-based programs more widely and effectively

Hierarchical Bayesian spatial models for multispecies conservation planning and monitoring.

Science.gov (United States)

Carroll, Carlos; Johnson, Devin S; Dunk, Jeffrey R; Zielinski, William J

2010-12-01

Biologists who develop and apply habitat models are often familiar with the statistical challenges posed by their data's spatial structure but are unsure of whether the use of complex spatial models will increase the utility of model results in planning. We compared the relative performance of nonspatial and hierarchical Bayesian spatial models for three vertebrate and invertebrate taxa of conservation concern (Church's sideband snails [Monadenia churchi], red tree voles [Arborimus longicaudus], and Pacific fishers [Martes pennanti pacifica]) that provide examples of a range of distributional extents and dispersal abilities. We used presence-absence data derived from regional monitoring programs to develop models with both landscape and site-level environmental covariates. We used Markov chain Monte Carlo algorithms and a conditional autoregressive or intrinsic conditional autoregressive model framework to fit spatial models. The fit of Bayesian spatial models was between 35 and 55% better than the fit of nonspatial analogue models. Bayesian spatial models outperformed analogous models developed with maximum entropy (Maxent) methods. Although the best spatial and nonspatial models included similar environmental variables, spatial models provided estimates of residual spatial effects that suggested how ecological processes might structure distribution patterns. Spatial models built from presence-absence data improved fit most for localized endemic species with ranges constrained by poorly known biogeographic factors and for widely distributed species suspected to be strongly affected by unmeasured environmental variables or population processes. By treating spatial effects as a variable of interest rather than a nuisance, hierarchical Bayesian spatial models, especially when they are based on a common broad-scale spatial lattice (here the national Forest Inventory and Analysis grid of 24 km(2) hexagons), can increase the relevance of habitat models to multispecies

Effect of H-wave polarization on laser radar detection of partially convex targets in random media.

Science.gov (United States)

El-Ocla, Hosam

2010-07-01

A study on the performance of laser radar cross section (LRCS) of conducting targets with large sizes is investigated numerically in free space and random media. The LRCS is calculated using a boundary value method with beam wave incidence and H-wave polarization. Considered are those elements that contribute to the LRCS problem including random medium strength, target configuration, and beam width. The effect of the creeping waves, stimulated by H-polarization, on the LRCS behavior is manifested. Targets taking large sizes of up to five wavelengths are sufficiently larger than the beam width and are sufficient for considering fairly complex targets. Scatterers are assumed to have analytical partially convex contours with inflection points.

The effect of random mass, stiffness and eccentricity parameters on seismic response of torsional system

International Nuclear Information System (INIS)

Ghafory-Ashtiany, M.

2001-01-01

In this paper, the effect of random eccentricity, mass and stiffness parameter on the dynamic characteristics of structure and story shear and torsional response has been comprehensively examined. Numerical results are obtained for a five-story torsional building excited by random excitation with various damping ration and frequency parameter values using both approaches of response calculations-a more accurate complex mode and an approximate normal mode have been used. The results show that the introduction of eccentricity in a direction introduces torsional moments in the system and reduces the direct story shear. For a safe design, eccentricity should be neglected in the calculations for shear, and a value of 0.05 of radius of gyration for calculation of torsional moment should be considered, even if a structure is intended to be symmetrical

Appropriate assessment of neighborhood effects on individual health: integrating random and fixed effects in multilevel logistic regression

DEFF Research Database (Denmark)

Larsen, Klaus; Merlo, Juan

2005-01-01

The logistic regression model is frequently used in epidemiologic studies, yielding odds ratio or relative risk interpretations. Inspired by the theory of linear normal models, the logistic regression model has been extended to allow for correlated responses by introducing random effects. However......, the model does not inherit the interpretational features of the normal model. In this paper, the authors argue that the existing measures are unsatisfactory (and some of them are even improper) when quantifying results from multilevel logistic regression analyses. The authors suggest a measure...... of heterogeneity, the median odds ratio, that quantifies cluster heterogeneity and facilitates a direct comparison between covariate effects and the magnitude of heterogeneity in terms of well-known odds ratios. Quantifying cluster-level covariates in a meaningful way is a challenge in multilevel logistic...

Combined Effect of Random Transmit Power Control and Inter-Path Interference Cancellation on DS-CDMA Packet Mobile Communications

Science.gov (United States)

Kudoh, Eisuke; Ito, Haruki; Wang, Zhisen; Adachi, Fumiyuki

In mobile communication systems, high speed packet data services are demanded. In the high speed data transmission, throughput degrades severely due to severe inter-path interference (IPI). Recently, we proposed a random transmit power control (TPC) to increase the uplink throughput of DS-CDMA packet mobile communications. In this paper, we apply IPI cancellation in addition to the random TPC. We derive the numerical expression of the received signal-to-interference plus noise power ratio (SINR) and introduce IPI cancellation factor. We also derive the numerical expression of system throughput when IPI is cancelled ideally to compare with the Monte Carlo numerically evaluated system throughput. Then we evaluate, by Monte-Carlo numerical computation method, the combined effect of random TPC and IPI cancellation on the uplink throughput of DS-CDMA packet mobile communications.

A Randomized-Controlled Trial Examining the Effects of Reflexology on Anxiety of Patients Undergoing Coronary Angiography

OpenAIRE

Molavi Vardanjani, Mehdi; Masoudi Alavi, Negin; Razavi, Narges Sadat; Aghajani, Mohammad; Azizi-Fini, Esmail; Vaghefi, Seied Morteza

2013-01-01

Background: The anxiety reduction before coronary angiography has clinical advantages and is one of the objectives of nursing. Reflexology is a non-invasive method that has been used in several clinical situations. Applying reflexology might have effect on the reduction of anxiety before coronary angiography. Objectives: The aim of this randomized clinical trial was to investigate the effect of reflexology on anxiety among patients undergoing coronary angiography. Patients and Methods: This t...

Boundary conditions in random sequential adsorption

Science.gov (United States)

Cieśla, Michał; Ziff, Robert M.

2018-04-01

The influence of different boundary conditions on the density of random packings of disks is studied. Packings are generated using the random sequential adsorption algorithm with three different types of boundary conditions: periodic, open, and wall. It is found that the finite size effects are smallest for periodic boundary conditions, as expected. On the other hand, in the case of open and wall boundaries it is possible to introduce an effective packing size and a constant correction term to significantly improve the packing densities.

Preoperative staging of lung cancer with PET/CT: cost-effectiveness evaluation alongside a randomized controlled trial

DEFF Research Database (Denmark)

Søgaard, Rikke; Fischer, Barbara Malene B; Mortensen, Jann

2011-01-01

PURPOSE: Positron emission tomography (PET)/CT has become a widely used technology for preoperative staging of non-small cell lung cancer (NSCLC). Two recent randomized controlled trials (RCT) have established its efficacy over conventional staging, but no studies have assessed its cost-effective......PURPOSE: Positron emission tomography (PET)/CT has become a widely used technology for preoperative staging of non-small cell lung cancer (NSCLC). Two recent randomized controlled trials (RCT) have established its efficacy over conventional staging, but no studies have assessed its cost......-effectiveness. The objective of this study was to assess the cost-effectiveness of PET/CT as an adjunct to conventional workup for preoperative staging of NSCLC. METHODS: The study was conducted alongside an RCT in which 189 patients were allocated to conventional staging (n = 91) or conventional staging + PET/CT (n = 98......) and followed for 1 year after which the numbers of futile thoracotomies in each group were monitored. A full health care sector perspective was adapted for costing resource use. The outcome parameter was defined as the number needed to treat (NNT)-here number of PET/CT scans needed-to avoid one futile...

The effect of endometrial scratch on natural-cycle cryopreserved embryo transfer outcomes: a randomized controlled study.

Science.gov (United States)

Mak, Jennifer Sze Man; Chung, Cathy Hoi Sze; Chung, Jacqueline Pui Wah; Kong, Grace Wing Shan; Saravelos, Sotirios H; Cheung, Lai Ping; Li, Tin-Chiu

2017-07-01

The benefit of endometrial scratch (ES) prior to embryo transfer is controversial. Systemic analysis has confirmed its potential benefit, especially in women with repeated IVF failures, yet most studies have focused on fresh embryo transfer, and its effect on vitrified-warmed embryo transfer (FET) cycles is yet to be explored. We hereby present our prospective, double-blind, randomized controlled study on the evaluation of the implantation and pregnancy rate after ES prior to natural-cycle FET. A total of 299 patients underwent natural-cycle FET and were randomized to receive ES (n = 115) or endocervical manipulation as control (n = 114) prior to FET cycle, and a total of 196 patients had embryo transfer (93 patients in each group). Our study showed no significant difference in the implantation and pregnancy rate, as well as the clinical and ongoing pregnancy or live birth rates between the two groups. It appears that ES does not have any beneficial effect on an unselected group of women undergoing FET in natural cycles. Further studies on its effect in women with recurrent implantation failure after IVF are warranted. Copyright © 2017 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

Effectiveness of PELOID therapy in carpal tunnel syndrome: A randomized controlled single blind study

Science.gov (United States)

Metin Ökmen, Burcu; Kasapoğlu Aksoy, Meliha; Güneş, Aygül; Eröksüz, Riza; Altan, Lale

2017-08-01

Carpal tunnel syndrome(CTS) is the most common neuromuscular cause of upper extremity disability. We aimed to investigate the effectiveness of peloid therapy in patients with CTS. This randomized, controlled, single-blind study enrolled 70 patients between the ages of 30 to 65 who had a diagnosis of either mild, mild-to-moderate, or moderate CTS. The patients were randomized into two groups using random number table. In the first group, (Group 1)( n = 35), patients were given splint (every night for 6 weeks) + peloid treatment(five consecutive days a week for 2 weeks) and in the second group, (Group 2)( n = 28), patients received splint treatment(every night for 6 weeks) alone. The patients were assessed by using visual analog scale(VAS) for pain, electroneuromyography(ENMG), the Boston Carpal Tunnel Syndrome Questionnaire(BCTSQ), hand grip strength(HGS), finger grip strength(FGS), and Short Form-12(SF-12). The data were obtained before treatment(W0), immediately after treatment(W2), and one month after treatment(W6). Both in Group 1 and 2, there was a statistically significant improvement in all the evaluation parameters at W2 and W6 when compared to W0( p < 0.05). Comparison of the groups with each other revealed significantly better results for VAS, BCTSQ, mSNCV, SF-12 in Group 1 than in Group 2 at W2( p < 0.05). There was also a statistically significant difference in favor of Group 1 for VAS, BCTSQ, FGS and MCS at W6 when compared to W0 ( p < 0.05). The results of our study demonstrated that in patients with CTS; peloid + splint treatment was more effective than splint treatment alone in pain, functionality and life quality both at after treatment(W2) and one month after treatment (W6). We may suggest peloid as a supplementary therapeutic agent in CTS.

RANDOM WALK HYPOTHESIS IN FINANCIAL MARKETS

Directory of Open Access Journals (Sweden)

Nicolae-Marius JULA

2017-05-01

Full Text Available Random walk hypothesis states that the stock market prices do not follow a predictable trajectory, but are simply random. If you are trying to predict a random set of data, one should test for randomness, because, despite the power and complexity of the used models, the results cannot be trustworthy. There are several methods for testing these hypotheses and the use of computational power provided by the R environment makes the work of the researcher easier and with a cost-effective approach. The increasing power of computing and the continuous development of econometric tests should give the potential investors new tools in selecting commodities and investing in efficient markets.

Effect of reducing indoor air pollution on women's respiratory symptoms and lung function: the RESPIRE Randomized Trial, Guatemala.

Science.gov (United States)

Smith-Sivertsen, Tone; Díaz, Esperanza; Pope, Dan; Lie, Rolv T; Díaz, Anaite; McCracken, John; Bakke, Per; Arana, Byron; Smith, Kirk R; Bruce, Nigel

2009-07-15

Exposure to household wood smoke from cooking is a risk factor for chronic obstructive lung disease among women in developing countries. The Randomized Exposure Study of Pollution Indoors and Respiratory Effects (RESPIRE) is a randomized intervention trial evaluating the respiratory health effects of reducing indoor air pollution from open cooking fires. A total of 504 rural Mayan women in highland Guatemala aged 15-50 years, all using traditional indoor open fires, were randomized to either receive a chimney woodstove (plancha) or continue using the open fire. Assessments of chronic respiratory symptoms and lung function and individual measurements of carbon monoxide exposure were performed at baseline and every 6 months up to 18 months. Use of a plancha significantly reduced carbon monoxide exposure by 61.6%. For all respiratory symptoms, reductions in risk were observed in the plancha group during follow-up; the reduction was statistically significant for wheeze (relative risk = 0.42, 95% confidence interval: 0.25, 0.70). The number of respiratory symptoms reported by the women at each follow-up point was also significantly reduced by the plancha (odds ratio = 0.7, 95% confidence interval: 0.50, 0.97). However, no significant effects on lung function were found after 12-18 months. Reducing indoor air pollution from household biomass burning may relieve symptoms consistent with chronic respiratory tract irritation.

Effects of aromatherapy massage on face-down posture-related pain after vitrectomy: a randomized controlled trial.

Science.gov (United States)

Adachi, Naho; Munesada, Minako; Yamada, Noriko; Suzuki, Haruka; Futohashi, Ayano; Shigeeda, Takashi; Kato, Satoshi; Nishigaki, Masakazu

2014-06-01

Postoperative face-down posturing (FDP) is recommended to optimize the effects of intraocular gas tamponade after vitrectomy. However, patients undergoing FDP usually experience physical and psychological burdens. This 3-armed, randomized, single-center trial investigated the effects of aromatherapy on FDP-related physical pain. Sixty-three patients under FDP were randomly allocated to one of three treatment groups: aromatherapy massage with essential oil (AT), oil massage without essential oil (OT), and a control group. The AT and OT groups received 10 minutes of massage by ward nurses trained by an aromatherapist, while the control group received usual care. Outcomes were assessed as short-term (pre- to post-intervention) and long-term (first to third postoperative day) changes in physical pain in five body regions using face-scale. The AT and OT groups both revealed similar short-term pain reductions after intervention, compared with the control group. Regarding long-term effects, neither group experienced significant effects until the second day. Significantly more pain reduction compared with usual care occurred on the third day, mainly in the AT group, though there were few significant differences between the AT and OT groups. In conclusion, this study suggests that simple oil massage is an effective strategy for immediate pain reduction in patients undergoing FDP, while aromatherapy may have a long-term effect on pain reduction. Copyright © 2014 American Society for Pain Management Nursing. Published by Elsevier Inc. All rights reserved.

Decoherence in optimized quantum random-walk search algorithm

International Nuclear Information System (INIS)

Zhang Yu-Chao; Bao Wan-Su; Wang Xiang; Fu Xiang-Qun

2015-01-01

This paper investigates the effects of decoherence generated by broken-link-type noise in the hypercube on an optimized quantum random-walk search algorithm. When the hypercube occurs with random broken links, the optimized quantum random-walk search algorithm with decoherence is depicted through defining the shift operator which includes the possibility of broken links. For a given database size, we obtain the maximum success rate of the algorithm and the required number of iterations through numerical simulations and analysis when the algorithm is in the presence of decoherence. Then the computational complexity of the algorithm with decoherence is obtained. The results show that the ultimate effect of broken-link-type decoherence on the optimized quantum random-walk search algorithm is negative. (paper)

Analgesic Effect of Intraperitoneal Bupivacaine Hydrochloride After Laparoscopic Sleeve Gastrectomy: a Randomized Clinical Trial.

Science.gov (United States)

Alamdari, Nasser Malekpour; Bakhtiyari, Mahmood; Gholizadeh, Barmak; Shariati, Catrine

2018-03-01

The indications for sleeve gastrectomy as a primary procedure for the surgical treatment of morbid obesity have increased worldwide. Pain is the most common complaint for patients on the first day after laparoscopic sleeve gastrectomy. There are various methods for decreasing pain after laparoscopic sleeve gastrectomy such as the use of intraperitoneal bupivacaine hydrochloride. This clinical trial was an attempt to discover the effects of intraperitoneal bupivacaine hydrochloride on alleviating postoperative pain after laparoscopic sleeve gastrectomy. In general, 120 patients meeting the inclusion criteria were enrolled. Patients were randomly allocated into two interventions and control groups using a balanced block randomization technique. One group received intraperitoneal bupivacaine hydrochloride (30 cm 3 ), and the other group served as the control one and did not receive bupivacaine hydrochloride. Diclofenac suppository and paracetamol injection were administered to both groups for postoperative pain management. The mean subjective postoperative pain score was significantly decreased in patients who received intraperitoneal bupivacaine hydrochloride within the first 24 h after the surgery; thus, the instillation of bupivacaine hydrochloride was beneficial in managing postoperative pain. The intraoperative peritoneal irrigation of bupivacaine hydrochloride (30 cm 3 , 0.25%) in sleeve gastrectomy patients was safe and effective in reducing postoperative pain, nausea, and vomiting (IRCT2016120329181N4).

Random regression models for detection of gene by environment interaction

Directory of Open Access Journals (Sweden)

Meuwissen Theo HE

2007-02-01

Full Text Available Abstract Two random regression models, where the effect of a putative QTL was regressed on an environmental gradient, are described. The first model estimates the correlation between intercept and slope of the random regression, while the other model restricts this correlation to 1 or -1, which is expected under a bi-allelic QTL model. The random regression models were compared to a model assuming no gene by environment interactions. The comparison was done with regards to the models ability to detect QTL, to position them accurately and to detect possible QTL by environment interactions. A simulation study based on a granddaughter design was conducted, and QTL were assumed, either by assigning an effect independent of the environment or as a linear function of a simulated environmental gradient. It was concluded that the random regression models were suitable for detection of QTL effects, in the presence and absence of interactions with environmental gradients. Fixing the correlation between intercept and slope of the random regression had a positive effect on power when the QTL effects re-ranked between environments.

KiVa Anti-Bullying Program in Italy: Evidence of Effectiveness in a Randomized Control Trial.

Science.gov (United States)

Nocentini, Annalaura; Menesini, Ersilia

2016-11-01

The present study aims to evaluate the effectiveness of the KiVa anti-bullying program in Italy through a randomized control trial of students in grades 4 and 6. The sample involved 2042 students (51 % female; grade 4, mean age = 8.85; ds = 0.43; grade 6, mean age = 10.93; ds = 0.50); 13 comprehensive schools were randomly assigned into intervention (KiVa) or control (usual school provision) conditions. Different outcomes (bullying, victimization, pro-bullying attitudes, pro-victim attitudes, empathy toward victims), analyses (longitudinal mixed model with multiple-item scales; longitudinal prevalence of bullies and victims using Olweus' single question), and estimates of effectiveness (Cohen's d; odds ratios) were considered in order to compare the Italian results with those from other countries. Multilevel models showed that KiVa reduced bullying and victimization and increased pro-victim attitudes and empathy toward the victim in grade 4, with effect sizes from 0.24 to 0.40. In grade 6, KiVa reduced bullying, victimization, and pro-bullying attitudes; the effects were smaller as compared to grade 4, yet significant (d ≥ 0.20). Finally, using Olweus dichotomous definition of bullies and victims, results showed that the odds of being a victim were 1.93 times higher for a control student than for a KiVa student in grade 4. Overall, the findings provide evidence of the effectiveness of the program in Italy; the discussion will focus on factors that influenced successfully the transportability of the KiVa program in Italy.

Does epicatechin contribute to the acute vascular function effects of dark chocolate? A randomized, crossover study

NARCIS (Netherlands)

Dower, James I.; Geleijnse, Marianne; Kroon, Paul A.; Philo, Mark; Mensink, Marco; Kromhout, Daan; Hollman, Peter C.H.

2016-01-01

Scope: Cocoa, rich in flavan-3-ols, improves vascular function, but the contribution of specific flavan-3-ols is unknown. We compared the effects of pure epicatechin, a major cocoa flavan-3-ol, and chocolate. Methods and results: In a randomized crossover study, twenty healthy men (40-80 years)

A network meta-analysis on randomized trials focusing on the preventive effect of statins on contrast-induced nephropathy

DEFF Research Database (Denmark)

Peruzzi, Mariangela; De Luca, Leonardo; Thomsen, Henrik S

2014-01-01

-analysis. Randomized trials focusing on statins were searched and pooled with random-effect odds ratios. A total of 14 trials (6,160 patients) were included, focusing on atorvastatin (high/low dose), rosuvastatin (high dose), simvastatin (high/low dose), and placebo or no statin therapy before contrast administration....... The risk of contrast-induced nephropathy was reduced by atorvastatin high dose and rosuvastatin high dose, with no difference between these two agents. Results for atorvastatin low dose and simvastatin (high/low dose) in comparison to placebo were inconclusive. Atorvastatin and rosuvastatin administered...

Nonlinear diffuse scattering of the random-phased wave

International Nuclear Information System (INIS)

Kato, Yoshiaki; Arinaga, Shinji; Mima, Kunioki.

1983-01-01

First experimental observation of the nonlinear diffuse scattering is reported. This new effect was observed in the propagation of the random-phased wave through a nonlinear dielectric medium. This effect is ascribed to the diffusion of the wavevector of the electro-magnetic wave to the lateral direction due to the randomly distributed nonlinear increase in the refractive index. (author)

Random a-adic groups and random net fractals

Energy Technology Data Exchange (ETDEWEB)

Li Yin [Department of Mathematics, Nanjing University, Nanjing 210093 (China)], E-mail: Lyjerry7788@hotmail.com; Su Weiyi [Department of Mathematics, Nanjing University, Nanjing 210093 (China)], E-mail: suqiu@nju.edu.cn

2008-08-15

Based on random a-adic groups, this paper investigates the relationship between the existence conditions of a positive flow in a random network and the estimation of the Hausdorff dimension of a proper random net fractal. Subsequently we describe some particular random fractals for which our results can be applied. Finally the Mauldin and Williams theorem is shown to be very important example for a random Cantor set with application in physics as shown in E-infinity theory.

Non-compact random generalized games and random quasi-variational inequalities

OpenAIRE

Yuan, Xian-Zhi

1994-01-01

In this paper, existence theorems of random maximal elements, random equilibria for the random one-person game and random generalized game with a countable number of players are given as applications of random fixed point theorems. By employing existence theorems of random generalized games, we deduce the existence of solutions for non-compact random quasi-variational inequalities. These in turn are used to establish several existence theorems of noncompact generalized random ...

Effects of Positive Psychology Interventions on Risk Biomarkers in Coronary Patients: A Randomized, Wait-List Controlled Pilot Trial.

Science.gov (United States)

Nikrahan, Gholam Reza; Laferton, Johannes A C; Asgari, Karim; Kalantari, Mehrdad; Abedi, Mohammad Reza; Etesampour, Ali; Rezaei, Abbas; Suarez, Laura; Huffman, Jeff C

2016-01-01

Among cardiac patients, positive psychologic factors are consistently linked with superior clinical outcomes and improvement in key markers of inflammation and hypothalamic-pituitary-adrenal axis functioning. Further, positive psychology interventions (PPI) have effectively increased psychologic well-being in a wide variety of populations. However, there has been minimal study of PPIs in cardiac patients, and no prior study has evaluated their effect on key prognostic biomarkers of cardiac outcome. Accordingly, we investigated the effect of 3 distinct PPIs on risk biomarkers in cardiac patients. In an exploratory trial, 69 patients with recent coronary artery bypass graft surgery or percutaneous intervention were randomized to (1) one of three 6-week in-person PPIs (based on the work of Seligman, Lyubomirsky, or Fordyce) or (2) a wait-list control group. Risk biomarkers were assessed at baseline, postintervention (7 weeks), and at 15-week follow-up. Between-group differences in change from baseline biomarker levels were examined via random effects models. Compared with the control group, participants randomized to the Seligman (B = -2.06; p = 0.02) and Fordyce PPI (B = -1.54; p = 0.04) had significantly lower high-sensitivity C-reactive protein levels at 7 weeks. Further, the Lyubomirsky PPI (B = -245.86; p = 0.04) was associated with a significantly lower cortisol awakening response at 7 weeks when compared with control participants. There were no other significant between-group differences. Despite being an exploratory pilot study with multiple between-group comparisons, this initial trial offers the first suggestion that PPIs might be effective in reducing risk biomarkers in high-risk cardiac patients. Copyright © 2016 The Academy of Psychosomatic Medicine. All rights reserved.

Metabolic and hormonal effects of caffeine: randomized, double-blind, placebo-controlled crossover trial.

Science.gov (United States)

MacKenzie, Todd; Comi, Richard; Sluss, Patrick; Keisari, Ronit; Manwar, Simone; Kim, Janice; Larson, Robin; Baron, John A

2007-12-01

In short-term studies, caffeine has been shown to increase insulin levels, reduce insulin sensitivity, and increase cortisol levels. However, epidemiological studies have indicated that long-term consumption of beverages containing caffeine such as coffee and green tea is associated with a reduced risk of type 2 diabetes mellitus. There is a paucity of randomized studies addressing the metabolic and hormonal effects of consuming caffeine over periods of more than 1 day. We evaluated the effect of oral intake of 200 mg of caffeine taken twice a day for 7 days on glucose metabolism, as well as on serum cortisol, dehydroepiandrosterone (DHEA), and androstenedione, and on nighttime salivary melatonin. A double-blind, randomized, placebo-controlled crossover study with periods of 7 days and washouts of 5 days comparing caffeine with placebo capsules was conducted. Participants were 16 healthy adults aged 18 to 22 years with a history of caffeine consumption. Blood samples from each subject were assayed for glucose, insulin, serum cortisol, DHEA, and androstenedione on the eighth day of each period after an overnight fast. Nighttime salivary melatonin was also measured. Insulin levels were significantly higher (by 1.80 microU/mL; 95% confidence interval, 0.33-3.28) after caffeine intake than after placebo. The homeostasis model assessment index of insulin sensitivity was reduced by 35% (95% confidence interval, 7%-62%) by caffeine. There were no differences in glucose, DHEA, androstenedione, and melatonin between treatment periods. This study provides evidence that daily caffeine intake reduces insulin sensitivity; the effect persists for at least a week and is evident up to 12 hours after administration.

The Effect of Changes in Physical Activity on Sedentary Behavior: Results From a Randomized Lifestyle Intervention Trial.

Science.gov (United States)

Siddique, Juned; de Chavez, Peter John; Craft, Lynette L; Freedson, Patty; Spring, Bonnie

2017-07-01

To investigate whether changes in physical activity (PA) have an impact on sedentary behavior (SB) during a lifestyle intervention. Study design was a randomized trial. Participants (n = 204) were individuals with low PA and high sedentary leisure screen time from the Chicago area. Participants were randomized to either increase PA (iPA) or decrease sedentary leisure (dSED). The intervention consisted of decision support, coaching, and financial incentives. For iPA participants, the goal was at least 60 min/d of self-reported moderate-tovigorous-intensity PA (MVPA). For dSED participants the goal was less than 90 min/d of sedentary leisure screen time. Daily accelerometer-based measures of SB and bout-corrected MVPA were obtained. Linear mixed-effects models were fit to estimate the effect of the intervention on MVPA and total SB and to estimate the effect of daily changes in MVPA on daily SB. The iPA participants increased their bout-corrected MVPA by 14 min/d (p much of this time by reducing their SB.

Intrinsic intensity fluctuations in random lasers

International Nuclear Information System (INIS)

Molen, Karen L. van der; Mosk, Allard P.; Lagendijk, Ad

2006-01-01

We present a quantitative experimental and theoretical study of intensity fluctuations in the emitted light of a random laser that has different realizations of disorder for every pump pulse. A model that clarifies these intrinsic fluctuations is developed. We describe the output versus input power graphs of the random laser with an effective spontaneous emission factor (β factor)

Effect of Risk of Bias on the Effect Size of Meta-Analytic Estimates in Randomized Controlled Trials in Periodontology and Implant Dentistry

Science.gov (United States)

Faggion, Clovis Mariano; Wu, Yun-Chun; Scheidgen, Moritz; Tu, Yu-Kang

2015-01-01

Background Risk of bias (ROB) may threaten the internal validity of a clinical trial by distorting the magnitude of treatment effect estimates, although some conflicting information on this assumption exists. Objective The objective of this study was evaluate the effect of ROB on the magnitude of treatment effect estimates in randomized controlled trials (RCTs) in periodontology and implant dentistry. Methods A search for Cochrane systematic reviews (SRs), including meta-analyses of RCTs published in periodontology and implant dentistry fields, was performed in the Cochrane Library in September 2014. Random-effect meta-analyses were performed by grouping RCTs with different levels of ROBs in three domains (sequence generation, allocation concealment, and blinding of outcome assessment). To increase power and precision, only SRs with meta-analyses including at least 10 RCTs were included. Meta-regression was performed to investigate the association between ROB characteristics and the magnitudes of intervention effects in the meta-analyses. Results Of the 24 initially screened SRs, 21 SRs were excluded because they did not include at least 10 RCTs in the meta-analyses. Three SRs (two from periodontology field) generated information for conducting 27 meta-analyses. Meta-regression did not reveal significant differences in the relationship of the ROB level with the size of treatment effect estimates, although a trend for inflated estimates was observed in domains with unclear ROBs. Conclusion In this sample of RCTs, high and (mainly) unclear risks of selection and detection biases did not seem to influence the size of treatment effect estimates, although several confounders might have influenced the strength of the association. PMID:26422698

Effect of oxygen therapy on chest pain in patients with ST elevation myocardial infarction: results from the randomized SOCCER trial.

Science.gov (United States)

Khoshnood, Ardavan; Akbarzadeh, Mahin; Carlsson, Marcus; Sparv, David; Bhiladvala, Pallonji; Mokhtari, Arash; Erlinge, David; Ekelund, Ulf

2018-04-01

Oxygen (O 2 ) have been a cornerstone in the treatment of acute myocardial infarction. Studies have been inconclusive regarding the cardiovascular and analgesic effects of oxygen in these patients. In the SOCCER trial, we compared the effects of oxygen treatment versus room air in patients with ST-elevation myocardial infarction (STEMI). There was no difference in myocardial salvage index or infarct size assessed with cardiac magnetic resonance imaging. In the present subanalysis, we wanted to evaluate the effect of O 2 on chest pain in patients with STEMI. Normoxic patients with first time STEMI were randomized in the ambulance to standard care with 10 l/min O 2 or room air until the end of the percutaneous coronary intervention (PCI). The ambulance personnel noted the patients´ chest pain on a visual analog scale (VAS; 1-10) before randomization and after the transport but before the start of the PCI, and also registered the amount of morphine given. 160 patients were randomized to O 2 (n = 85) or room air (n = 75). The O 2 group had a higher median VAS at randomization than the air group (7.0 ± 2.3 vs 6.0 ± 2.9; p = .02) and also received a higher median total dose of morphine (5.0 mg ± 4.4 vs 4.0 mg ± 3.7; p = .02). There was no difference between the O 2 and air groups in VAS at the start of the PCI (4.0 ± 2.4 vs 3.0 ± 2.5; p = .05) or in the median VAS decrease from randomization to the start of the PCI (-2.0 ± 2.2 vs -1.0 ± 2.9; p = .18). Taken together with previously published data, these results do not support a significant analgesic effect of oxygen in patients with STEMI. European Clinical Trials Database (EudraCT): 2011-001452-11. ClinicalTrials.gov Identifier: NCT01423929.

Effects of Horticulture on Frail and Prefrail Nursing Home Residents: A Randomized Controlled Trial.

Science.gov (United States)

Lai, Claudia K Y; Kwan, Rick Y C; Lo, Shirley K L; Fung, Connie Y Y; Lau, Jordan K H; Tse, Mimi M Y

2018-05-24

Frail nursing home residents face multiple health challenges as a result of their frail status. The aim of this study was to examine the effects of HT on the psychosocial well-being of frail and prefrail nursing home residents. Randomized controlled trial. Nursing homes. One hundred eleven participants were randomly allocated into the intervention [horticultural therapy (HT)] and control (social activities) conditions. HT group participants attended a weekly 60-minute session for 8 consecutive weeks. Control group activities were social in nature, without any horticulture components. The outcome measures include happiness, depressive symptoms, self-efficacy, well-being, social network, and social engagement. The time points of measurement were at baseline (T 0 ), immediately postintervention (T 1 ), and 12 weeks postintervention (T 2 ). A modified intention-to-treat approach was adopted. A multivariate general estimating equation was used to analyze the data. Forty-six and 50 participants received at least 1 session of the intervention and control condition protocol, respectively. A significant interaction effect between group and time was observed only on the happiness scale (β = 1.457, P = .036), but not on other outcome variables. In a follow-up cluster analysis of those who received HT, a greater effect on subjective happiness (mean difference = 6.23, P < .001) was observed for participants who were happier at baseline. HT was found to be effective in promoting subjective happiness for frail and prefrail nursing home residents. Its favorable effect suggests that HT should be used to promote the psychosocial well-being of those who are frail. Copyright © 2018 AMDA – The Society for Post-Acute and Long-Term Care Medicine. Published by Elsevier Inc. All rights reserved.

Effectiveness of Cerium Nitrate-Silver Sulfadiazine in the Treatment of Facial Burns: A Multicenter, Randomized, Controlled Trial

NARCIS (Netherlands)

Oen, I.M.M.H.; van Baar, M.E.; Middelkoop, E.; Nieuwenhuis, M.K.

2012-01-01

Background: The face is a very frequent site of burn injuries. This multicenter, randomized, controlled trial thus investigates the effectiveness of cerium nitrate-silver sulfadiazine in the treatment of facial burns compared with silver sulfadiazine. Methods: Adult patients with acute facial burns

Cardiorespiratory fitness moderates the effect of an affect-guided physical activity prescription: A pilot randomized controlled trial

NARCIS (Netherlands)

Baldwin, A.S.; Kangas, J.L.; Denman, D.C.; Smits, J.A.J.; Yamada, T.; Otto, M.W.

2016-01-01

Physical activity (PA) interventions have a clear role in promoting mental health. Current PA guidelines directed toward specific PA intensities may have negative effects on affective response to exercise, and affective response is an important determinant of PA adherence. In this randomized trial

Sound production treatment for acquired apraxia of speech: Effects of blocked and random practice on multisyllabic word production.

Science.gov (United States)

Wambaugh, Julie; Nessler, Christina; Wright, Sandra; Mauszycki, Shannon; DeLong, Catharine

2016-10-01

This study was designed to examine the effects of practice schedule, blocked vs random, on outcomes of a behavioural treatment for acquired apraxia of speech (AOS), Sound Production Treatment (SPT). SPT was administered to four speakers with chronic AOS and aphasia in the context of multiple baseline designs across behaviours and participants. Treatment was applied to multiple sound errors within three-to-five syllable words. All participants received both practice schedules: SPT-Random (SPT-R) and SPT-Blocked (SPT-B). Improvements in accuracy of word production for trained items were found for both treatment conditions for all participants. One participant demonstrated better maintenance effects associated with SPT-R. Response generalisation to untreated words varied across participants, but was generally modest and unstable. Stimulus generalisation to production of words in sentence completion was positive for three of the participants. Stimulus generalisation to production of phrases was positive for two of the participants. Findings provide additional efficacy data regarding SPT's effects on articulation of treated items and extend knowledge of the treatment's effects when applied to multiple targets within multisyllabic words.

Effects of nattokinase on blood pressure: a randomized, controlled trial.

Science.gov (United States)

Kim, Ji Young; Gum, Si Nae; Paik, Jean Kyung; Lim, Hyo Hee; Kim, Kyong-Chol; Ogasawara, Kazuya; Inoue, Kenichi; Park, Sungha; Jang, Yangsoo; Lee, Jong Ho

2008-08-01

The objective of this study was to examine the effects of nattokinase supplementation on blood pressure in subjects with pre-hypertension or stage 1 hypertension. In a randomized, double-blind, placebo-controlled trial, 86 participants ranging from 20 to 80 years of age with an initial untreated systolic blood pressure (SBP) of 130 to 159 mmHg received nattokinase (2,000 FU/capsule) or a placebo capsule for 8 weeks. Seventy-three subjects completed the protocol. Compared with the control group, the net changes in SBP and diastolic blood pressure (DBP) were -5.55 mmHg (95% confidence interval [CI], -10.5 to -0.57 mmHg; pnattokinase group compared with the control group (pnattokinase supplementation resulted in a reduction in SBP and DBP. These findings suggest that increased intake of nattokinase may play an important role in preventing and treating hypertension.

Anomalous Anticipatory Responses in Networked Random Data

International Nuclear Information System (INIS)

Nelson, Roger D.; Bancel, Peter A.

2006-01-01

We examine an 8-year archive of synchronized, parallel time series of random data from a world spanning network of physical random event generators (REGs). The archive is a publicly accessible matrix of normally distributed 200-bit sums recorded at 1 Hz which extends from August 1998 to the present. The primary question is whether these data show non-random structure associated with major events such as natural or man-made disasters, terrible accidents, or grand celebrations. Secondarily, we examine the time course of apparently correlated responses. Statistical analyses of the data reveal consistent evidence that events which strongly affect people engender small but significant effects. These include suggestions of anticipatory responses in some cases, leading to a series of specialized analyses to assess possible non-random structure preceding precisely timed events. A focused examination of data collected around the time of earthquakes with Richter magnitude 6 and greater reveals non-random structure with a number of intriguing, potentially important features. Anomalous effects in the REG data are seen only when the corresponding earthquakes occur in populated areas. No structure is found if they occur in the oceans. We infer that an important contributor to the effect is the relevance of the earthquake to humans. Epoch averaging reveals evidence for changes in the data some hours prior to the main temblor, suggestive of reverse causation

Effectiveness of smoking-cessation interventions for urban hospital patients: study protocol for a randomized controlled trial

Directory of Open Access Journals (Sweden)

Grossman Ellie

2012-08-01

Full Text Available Abstract Background Hospitalization may be a particularly important time to promote smoking cessation, especially in the immediate post-discharge period. However, there are few studies to date that shed light on the most effective or cost-effective methods to provide post-discharge cessation treatment, especially among low-income populations and those with a heavy burden of mental illness and substance use disorders. Methods/design This randomized trial will compare the effectiveness and cost-effectiveness of two approaches to smoking cessation treatment among patients discharged from two urban public hospitals in New York City. During hospitalization, staff will be prompted to ask about smoking and to offer nicotine replacement therapy (NRT on admission and at discharge. Subjects will be randomized on discharge to one of two arms: one arm will be proactive multi-session telephone counseling with motivational enhancement delivered by study staff, and the other will be a faxed or online referral to the New York State Quitline. The primary outcome is 30-day point-prevalence abstinence from smoking at 6-month follow-up post-discharge. We will also examine cost-effectiveness from a societal and a payer perspective, as well as explore subgroup analyses related to patient location of hospitalization, race/ethnicity, immigrant status, and inpatient diagnosis. Discussion This study will explore issues of implementation feasibility in a post-hospitalization patient population, as well as add information about the effectiveness and cost-effectiveness of different strategies for designing smoking cessation programs for hospitalized patients. Trial registration Clinicaltrials.gov ID# NCT01363245

Ageing and memory effects in the weak random anisotropy magnets amorphous NdGdFe and HoGdFe

International Nuclear Information System (INIS)

Saito, Toshiaki; Emura, Ai; Hanashima, Koji

2007-01-01

We experimentally examined the ageing phenomena in typical weak random anisotropy magnets (weak RAMs), amorphous NdGdFe and HoGdFe, with a small ratio of the random anisotropy (D) to the ferromagnetic exchange (J) (D/J). These weak RAMs have very long average relaxation time, two or three orders longer than that of spin glasses (SGs) around the transition temperature, and also have a very large ac excitation field (h 0 ) dependence of the ac susceptibility. Measuring the imaginary part of the ac susceptibility at frequency of 0.5 Hz and h 0 of 0.3 Oe by using two temperature-change protocols, we observed the memory and rejuvenation effects as reported in SGs, but the effects are weaker in the present weak RAMs, suggesting that the picture of the hierarchical structure of the free energy space is also effective in weak RAMs as in SGs, but it may have smaller barrier heights than those of SGs

The Effect of Iron Status on Risk of Coronary Artery Disease: A Mendelian Randomization Study-Brief Report.

Science.gov (United States)

Gill, Dipender; Del Greco M, Fabiola; Walker, Ann P; Srai, Surjit K S; Laffan, Michael A; Minelli, Cosetta

2017-09-01

Iron status is a modifiable trait that has been implicated in cardiovascular disease. This study uses the Mendelian randomization technique to investigate whether there is any causal effect of iron status on risk of coronary artery disease (CAD). A 2-sample Mendelian randomization approach is used to estimate the effect of iron status on CAD risk. Three loci (rs1800562 and rs1799945 in the HFE gene and rs855791 in TMPRSS6 ) that are each associated with serum iron, transferrin saturation, ferritin, and transferrin in a pattern suggestive of an association with systemic iron status are used as instruments. SNP (single-nucleotide polymorphism)-iron status association estimates are based on a genome-wide association study meta-analysis of 48 972 individuals. SNP-CAD estimates are derived by combining the results of a genome-wide association study meta-analysis of 60 801 CAD cases and 123 504 controls with those of a meta-analysis of 63 746 CAD cases and 130 681 controls obtained from Metabochip and genome-wide association studies. Combined Mendelian randomization estimates are obtained for each marker by pooling results across the 3 instruments. We find evidence of a protective effect of higher iron status on CAD risk (iron odds ratio, 0.94 per SD unit increase; 95% confidence interval, 0.88-1.00; P =0.039; transferrin saturation odds ratio, 0.95 per SD unit increase; 95% confidence interval, 0.91-0.99; P =0.027; log-transformed ferritin odds ratio, 0.85 per SD unit increase; 95% confidence interval, 0.73-0.98; P =0.024; and transferrin odds ratio, 1.08 per SD unit increase; 95% confidence interval, 1.01-1.16; P =0.034). This Mendelian randomization study supports the hypothesis that higher iron status reduces CAD risk. These findings may highlight a therapeutic target. © 2017 American Heart Association, Inc.

Effects of prenatal yoga on women's stress and immune function across pregnancy: A randomized controlled trial.

Science.gov (United States)

Chen, Pao-Ju; Yang, Luke; Chou, Cheng-Chen; Li, Chia-Chi; Chang, Yu-Cune; Liaw, Jen-Jiuan

2017-04-01

The effects of prenatal yoga on biological indicators have not been widely studied. Thus, we compared changes in stress and immunity salivary biomarkers from 16 to 36 weeks' gestation between women receiving prenatal yoga and those receiving routine prenatal care. For this longitudinal, prospective, randomized controlled trial, we recruited 94 healthy pregnant women at 16 weeks' gestation through convenience sampling from a prenatal clinic in Taipei. Participants were randomly assigned to intervention (n=48) or control (n=46) groups using Clinstat block randomization. The 20-week intervention comprised two weekly 70-min yoga sessions led by a midwife certified as a yoga instructor; the control group received only routine prenatal care. In both groups, participants' salivary cortisol and immunoglobulin A levels were collected before and after yoga every 4 weeks from 16 to 36 weeks' gestation. The intervention group had lower salivary cortisol (pcontrol group. Specifically, the intervention group had significantly higher long-term salivary immunoglobulin A levels than the control group (p=0.018), and infants born to women in the intervention group weighed more than those born to the control group (pPrenatal yoga significantly reduced pregnant women's stress and enhanced their immune function. Clinicians should learn the mechanisms of yoga and its effects on pregnant women. Our findings can guide clinicians to help pregnant women alleviate their stress and enhance their immune function. Copyright © 2017. Published by Elsevier Ltd.

Assessment of effectiveness of smoking cessation intervention among male prisoners in India: A randomized controlled trial.

Science.gov (United States)

Naik, Sachin; Khanagar, Sanjeev; Kumar, Amit; Ramachandra, Sujith; Vadavadagi, Sunil V; Dhananjaya, Kiran Murthy

2014-12-01

Tobacco smoking is an integral part of prison life and an established part of the culture. Little attention has been paid to prevention of smoking in prison. Approximately 70-80% of prisoners have been identified as current smokers. To assess the effectiveness of smoking cessation intervention among male prisoners at Central Jail, Bangalore city. To assess the effectiveness of smoking cessation intervention among male prisoners at Central Jail, Bangalore city. A randomized controlled trial was planned among male prisoners in Central Jail, Bangalore city. There were 1600 convicted prisoners. A self-administered questionnaire was given to the prisoners to assess their smoking behavior by which prevalence of tobacco smoking was found. Exactly 1352 tobacco users were studied. Among them, there were 1252 smokers. Based on inclusion criteria and informed consent given by the prisoners, a sample of 600 was chosen for the study by systematic random sampling. Among the 600 prisoners, 300 were randomly selected for the study group and 300 for the control group. Prevalence of tobacco smoking among the prisoners was 92.60%. In the present study, after smoking cessation intervention, 17% showed no change in smoking, 21.66% reduced smoking, 16% stopped smoking, and 45.33% relapsed (P prison even if the living conditions are not favorable. Relatively high rate of relapse in our study indicates that some policies should be adopted to improve smokers' information on consequences of tobacco on health and motivational intervention should be added to prisoners.

The effect of pheniramine on fentanyl-induced cough: a randomized, double blinded, placebo controlled clinical study.

Science.gov (United States)

Arslan, Zakir; Çalık, Eyup Serhat; Kaplan, Bekir; Ahiskalioglu, Elif Oral

2016-01-01

There are many studies conducted on reducing the frequency and severity of fentayl-induced cough during anesthesia induction. We propose that pheniramine maleate, an antihistaminic, may suppress this cough. We aim to observe the effect of pheniramine on fentanyl-induced cough during anesthesia induction. This is a double-blinded, prospective, three-arm parallel, randomized clinical trial of 120 patients with ASA (American Society of Anesthesiologists) physical status III and IV who aged ≥18 and scheduled for elective open heart surgery during general anesthesia. Patients were randomly assigned to three groups of 40 patients, using computer-generated random numbers: placebo group, pheniramine group, and lidocaine group. Cough incidence differed significantly between groups. In the placebo group, 37.5% of patients had cough, whereas the frequency was significantly decreased in pheniramine group (5%) and lidocaine group (15%) (Fischer exact test, p=0.0007 and p=0.0188, respectively). There was no significant change in cough incidence between pheniramine group (5%) and lidocaine group (15%) (Fischer exact test, p=0.4325). Cough severity did also change between groups. Post Hoc tests with Bonferroni showed that mean cough severity in placebo differed significantly than that of pheniramine group and lidocaine group (ppheniramine group and lidocaine group (p=0.856). Intravenous pheniramine is as effective as lidocaine in preventing fentayl-induced cough. Our results emphasize that pheniramine is a convenient drug to decrease this cough. Copyright © 2015 Sociedade Brasileira de Anestesiologia. Published by Elsevier Editora Ltda. All rights reserved.

[The effect of pheniramine on fentanyl-induced cough: a randomized, double blinded, placebo controlled clinical study].

Science.gov (United States)

Arslan, Zakir; Çalık, Eyup Serhat; Kaplan, Bekir; Ahiskalioglu, Elif Oral

2016-01-01

There are many studies conducted on reducing the frequency and severity of fentayl-induced cough during anesthesia induction. We propose that pheniramine maleate, an antihistaminic, may suppress this cough. We aim to observe the effect of pheniramine on fentanyl-induced cough during anesthesia induction. This is a double-blinded, prospective, three-arm parallel, randomized clinical trial of 120 patients with ASA (American Society of Anesthesiologists) physical status III and IV who aged ≥18 and scheduled for elective open heart surgery during general anesthesia. Patients were randomly assigned to three groups of 40 patients, using computer-generated random numbers: placebo group, pheniramine group, and lidocaine group. Cough incidence differed significantly between groups. In the placebo group, 37.5% of patients had cough, whereas the frequency was significantly decreased in pheniramine group (5%) and lidocaine group (15%) (Fischer exact test, p=0.0007 and p=0.0188, respectively). There was no significant change in cough incidence between pheniramine group (5%) and lidocaine group (15%) (Fischer exact test, p=0.4325). Cough severity did also change between groups. Post Hoc tests with Bonferroni showed that mean cough severity in placebo differed significantly than that of pheniramine group and lidocaine group (ppheniramine group and lidocaine group (p=0.856). Intravenous pheniramine is as effective as lidocaine in preventing fentayl-induced cough. Our results emphasize that pheniramine is a convenient drug to decrease this cough. Copyright © 2015 Sociedade Brasileira de Anestesiologia. Publicado por Elsevier Editora Ltda. All rights reserved.

The Effect of External Apple Vinegar Application on Varicosity Symptoms, Pain, and Social Appearance Anxiety: A Randomized Controlled Trial

Directory of Open Access Journals (Sweden)

Derya Atik

2016-01-01

Full Text Available Aim. We aimed to determine the effect of external apple vinegar application on the symptoms and social appearance anxiety of varicosity patients who were suggested conservative treatment. Method. The study was planned as an experimental, randomized, and controlled study. 120 patients were randomly selected and then were randomly allocated to either experimental or control group by simple blind random sampling method. In the collection of research data, a questionnaire questioning sociodemographic and clinical characteristics, the Visual Analog Scale (VAS for pain, and the Social Appearance Anxiety Scale (SAAS were used. The patients in the study group were suggested to apply apple vinegar to the area of the leg with varicosity alongside the treatment suggested by the doctor. The patients in the control group received no intervention during the study. Results. The sociodemographic and clinic characteristics of both groups were found to be similar (p>0.05. The patients were evaluated with regard to cramps, pain, leg fatigue perception, edema, itching, pigmentation, and weight feelings in the leg, VAS, and SAAS averages in the second evaluation; the control group had a decrease in such symptoms (p>0.05 although the decrease in the application group was higher and statistically meaningful (p<0.05. Conclusion. We determined that the external application of apple vinegar on varicosity patients, which is a very easy application, increased the positive effects of conservative treatment.

Effectiveness of a selective intervention program targeting personality risk factors for alcohol misuse among young adolescents: results of a cluster randomized controlled trial

NARCIS (Netherlands)

Lammers, J.; Goossens, F.; Conrod, P.; Engels, R.C.M.E.; Wiers, R.W.H.J.; Kleinjan, M.

2015-01-01

Aim The effectiveness of Preventure was tested on drinking behaviour of young adolescents in secondary education in the Netherlands. Design A cluster randomized controlled trial was carried out, with participants assigned randomly to a two-session coping skills intervention or a control

Effect of magnetic helicity upon rectilinear propagation of charged particles in random magnetic fields

Science.gov (United States)

Earl, James A.

1992-01-01

When charged particles spiral along a large constant magnetic field, their trajectories are scattered by any random field components that are superposed on the guiding field. If the random field configuration embodies helicity, the scattering is asymmetrical with respect to a plane perpendicular to the guiding field, for particles moving into the forward hemisphere are scattered at different rates from those moving into the backward hemisphere. This asymmetry gives rise to new terms in the transport equations that describe propagation of charged particles. Helicity has virtually no impact on qualitative features of the diffusive mode of propagation. However, characteristic velocities of the coherent modes that appear after a highly anisotropic injection exhibit an asymmetry related to helicity. Explicit formulas, which embody the effects of helicity, are given for the anisotropies, the coefficient diffusion, and the coherent velocities. Predictions derived from these expressions are in good agreement with Monte Carlo simulations of particle transport, but the simulations reveal certain phenomena whose explanation calls for further analytical work.

Effect of Buprenorphine Weekly Depot (CAM2038) and Hydromorphone Blockade in Individuals With Opioid Use Disorder: A Randomized Clinical Trial.

Science.gov (United States)

Walsh, Sharon L; Comer, Sandra D; Lofwall, Michelle R; Vince, Bradley; Levy-Cooperman, Naama; Kelsh, Debra; Coe, Marion A; Jones, Jermaine D; Nuzzo, Paul A; Tiberg, Fredrik; Sheldon, Behshad; Kim, Sonnie

2017-09-01

Buprenorphine is an efficacious, widely used treatment for opioid use disorder (OUD). Daily oral transmucosal formulations can be associated with misuse, diversion, and nonadherence; these limitations may be obviated by a sustained release formulation. To evaluate the ability of a novel, weekly, subcutaneous buprenorphine depot formulation, CAM2038, to block euphorigenic opioid effects and suppress opioid withdrawal in non-treatment-seeking individuals with OUD. This multisite, double-blind, randomized within-patient study was conducted at 3 controlled inpatient research facilities. It involved 47 adults with DSM-V moderate-to-severe OUD. The study was conducted from October 12, 2015 (first patient enrolled), to April 21, 2016 (last patient visit). A total of five 3-day test sessions evaluated the response to hydromorphone (0, 6, and 18 mg intramuscular in random order; 1 dose/session/day). After the first 3-day session (ie, qualification phase), participants were randomized to either CAM2038 weekly at 24 mg (n = 22) or 32 mg (n = 25); the assigned CAM2038 dose was given twice, 1 week apart (day 0 and 7). Four sets of sessions were conducted after randomization (days 1-3, 4-6, 8-10, and 11-13). The primary end point was maximum rating on the visual analog scale for drug liking. Secondary end points included other visual analog scale (eg, high and desire to use), opioid withdrawal scales, and physiological and pharmacokinetic outcomes. A total of 46 of 47 randomized participants (mean [SD] age, 35.5 [9] years; 76% male [n = 35]) completed the study. Both weekly CAM2038 doses produced immediate and sustained blockade of hydromorphone effects (liking maximum effect, CAM2038, 24 mg: effect size, 0.813; P withdrawal (Clinical Opiate Withdrawal Scale, CAM2038, 24 mg: effect size, 0.617; P opioid blockade and withdrawal suppression. The results support the use of this depot formulation for treatment initiation and stabilization of patients with OUD, with

Effect of Probiotics on Serum Bilirubin Level in Term Neonates with Jaundice; A Randomized Clinical Trial

OpenAIRE

Yadollah Zahed Pasha; Mousa Ahmadpour-kacho; Abes Ahmadi Jazi; Hemmat Gholinia

2017-01-01

Background In recent years, tendency to use drugs has been increasing in the treatment of neonatal jaundice. Several drugs have been used since then, but the effect of probiotics on serum bilirubin level (SBL) is not so clear. This study was conducted to evaluate the effect of probiotics on SBL and the duration of phototherapy in term neonates with hyperbilirubinemia. Materials and Methods: In this randomized clinical trial, we studied 150 term neonate with jaundice hospitalized for photother...

Percolation, statistical topography, and transport in random media

International Nuclear Information System (INIS)

Isichenko, M.B.

1992-01-01

A review of classical percolation theory is presented, with an emphasis on novel applications to statistical topography, turbulent diffusion, and heterogeneous media. Statistical topography involves the geometrical properties of the isosets (contour lines or surfaces) of a random potential ψ(x). For rapidly decaying correlations of ψ, the isopotentials fall into the same universality class as the perimeters of percolation clusters. The topography of long-range correlated potentials involves many length scales and is associated either with the correlated percolation problem or with Mandelbrot's fractional Brownian reliefs. In all cases, the concept of fractal dimension is particularly fruitful in characterizing the geometry of random fields. The physical applications of statistical topography include diffusion in random velocity fields, heat and particle transport in turbulent plasmas, quantum Hall effect, magnetoresistance in inhomogeneous conductors with the classical Hall effect, and many others where random isopotentials are relevant. A geometrical approach to studying transport in random media, which captures essential qualitative features of the described phenomena, is advocated

Effects of a Worksite Weight-Control Programme in Obese Male Workers: A Randomized Controlled Crossover Trial

Science.gov (United States)

Iriyama, Yae; Murayama, Nobuko

2014-01-01

Objective: We conducted a randomized controlled crossover trial to evaluate the effects of a new worksite weight-control programme designed for men with or at risk of obesity using a combination of nutrition education and nutrition environmental interventions. Subjects and methods: Male workers with or at risk of obesity were recruited for this…

The Effects of Legumes on Metabolic Features, Insulin Resistance and Hepatic Function Tests in Women with Central Obesity: A Randomized Controlled Trial

OpenAIRE

Mohammad Alizadeh; Rasool Gharaaghaji; Bahram Pourghassem Gargari

2014-01-01

Background: The effect of high-legume hypocaloric diet on metabolic features in women is unclear. This study provided an opportunity to find effects of high-legume diet on metabolic features in women who consumed high legumes at pre-study period. Methods: In this randomized controlled trial after 2 weeks of a run-in period on an isocaloric diet, 42 premenopausal women with central obesity were randomly assigned into two groups: (1) Hypocaloric diet enriched in legumes (HDEL) and (2) hypoc...

MendelianRandomization: an R package for performing Mendelian randomization analyses using summarized data.

Science.gov (United States)

Yavorska, Olena O; Burgess, Stephen

2017-12-01

MendelianRandomization is a software package for the R open-source software environment that performs Mendelian randomization analyses using summarized data. The core functionality is to implement the inverse-variance weighted, MR-Egger and weighted median methods for multiple genetic variants. Several options are available to the user, such as the use of robust regression, fixed- or random-effects models and the penalization of weights for genetic variants with heterogeneous causal estimates. Extensions to these methods, such as allowing for variants to be correlated, can be chosen if appropriate. Graphical commands allow summarized data to be displayed in an interactive graph, or the plotting of causal estimates from multiple methods, for comparison. Although the main method of data entry is directly by the user, there is also an option for allowing summarized data to be incorporated from the PhenoScanner database of genotype-phenotype associations. We hope to develop this feature in future versions of the package. The R software environment is available for download from [https://www.r-project.org/]. The MendelianRandomization package can be downloaded from the Comprehensive R Archive Network (CRAN) within R, or directly from [https://cran.r-project.org/web/packages/MendelianRandomization/]. Both R and the MendelianRandomization package are released under GNU General Public Licenses (GPL-2|GPL-3). © The Author 2017. Published by Oxford University Press on behalf of the International Epidemiological Association.

How random are random numbers generated using photons?

International Nuclear Information System (INIS)

Solis, Aldo; Angulo Martínez, Alí M; Ramírez Alarcón, Roberto; Cruz Ramírez, Hector; U’Ren, Alfred B; Hirsch, Jorge G

2015-01-01

Randomness is fundamental in quantum theory, with many philosophical and practical implications. In this paper we discuss the concept of algorithmic randomness, which provides a quantitative method to assess the Borel normality of a given sequence of numbers, a necessary condition for it to be considered random. We use Borel normality as a tool to investigate the randomness of ten sequences of bits generated from the differences between detection times of photon pairs generated by spontaneous parametric downconversion. These sequences are shown to fulfil the randomness criteria without difficulties. As deviations from Borel normality for photon-generated random number sequences have been reported in previous work, a strategy to understand these diverging findings is outlined. (paper)

Unbiased All-Optical Random-Number Generator

Science.gov (United States)

Steinle, Tobias; Greiner, Johannes N.; Wrachtrup, Jörg; Giessen, Harald; Gerhardt, Ilja

2017-10-01

The generation of random bits is of enormous importance in modern information science. Cryptographic security is based on random numbers which require a physical process for their generation. This is commonly performed by hardware random-number generators. These often exhibit a number of problems, namely experimental bias, memory in the system, and other technical subtleties, which reduce the reliability in the entropy estimation. Further, the generated outcome has to be postprocessed to "iron out" such spurious effects. Here, we present a purely optical randomness generator, based on the bistable output of an optical parametric oscillator. Detector noise plays no role and postprocessing is reduced to a minimum. Upon entering the bistable regime, initially the resulting output phase depends on vacuum fluctuations. Later, the phase is rigidly locked and can be well determined versus a pulse train, which is derived from the pump laser. This delivers an ambiguity-free output, which is reliably detected and associated with a binary outcome. The resulting random bit stream resembles a perfect coin toss and passes all relevant randomness measures. The random nature of the generated binary outcome is furthermore confirmed by an analysis of resulting conditional entropies.

Periodontal Therapy Effects on Nitrite Related to Oral Bacteria: A 6-Month Randomized Clinical Trial.

Science.gov (United States)

Cortelli, Sheila C; Costa, Fernando O; Rodrigues, Edson; Cota, Luis O M; Cortelli, Jose R

2015-08-01

Nitrite is a biologic factor relevant to oral and systemic homeostasis. Through an oral bacteria reduction process, it was suggested that periodontal therapy and chlorhexidine (CHX) rinse could affect nitrite levels, leading to negative effects, such as an increase in blood pressure. This 6-month randomized clinical trial evaluated the effects of periodontal therapeutic protocols on salivary nitrite and its relation to subgingival bacteria. One hundred patients with periodontitis were allocated randomly to debridement procedures in four weekly sections (quadrant scaling [QS]) or within 24 hours (full-mouth scaling [FMS]) in conjunction with a 60-day CHX (QS + CHX and FMS + CHX), placebo (QS + placebo and FMS + placebo), or no mouthrinse (QS + none and FMS + none) use. Real-time polymerase chain reaction determined total bacterial, Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Streptococcus oralis, and Actinomyces naeslundii levels. Salivary nitrite concentration was determined with Griess reagent. Data were analyzed statistically at baseline and 3 and 6 months by analysis of variance, Kruskal-Wallis, Mann-Whitney U, and Spearman correlation tests (P periodontal pockets. The relationship between nitrite and bacterial levels appears weak. Short-term scaling exhibited a greater influence on nitrite concentrations then long-term CHX use.

Effectiveness of the 'Healthy School and Drugs' prevention programme on adolescents' substance use: a randomized clustered trial

NARCIS (Netherlands)

Malmberg, M.; Kleinjan, M.; Overbeek, G.; Vermulst, A.; Monshouwer, K.; Lammers, J.; Vollebergh, W.A.M.; Engels, R.C.M.E.

2014-01-01

Aim: To evaluate the effectiveness of the Healthy School and Drugs programme on alcohol, tobacco and marijuana use among Dutch early adolescents. Design: Randomized clustered trial with two intervention conditions (i.e. e-learning and integral). Setting: General population of 11-15-year-old

Effectiveness of the 'Healthy School and Drugs' prevention programme on adolescents' substance use : A randomized clustered trial

NARCIS (Netherlands)

Malmberg, Monique; Kleinjan, Marloes; Overbeek, Geertjan; Vermulst, Ad; Monshouwer, Karin; Lammers, Jeroen; Vollebergh, Wilma A M; Engels, Rutger C M E

2014-01-01

Aim: To evaluate the effectiveness of the Healthy School and Drugs programme on alcohol, tobacco and marijuana use among Dutch early adolescents. Design: Randomized clustered trial with two intervention conditions (i.e. e-learning and integral). Setting: General population of 11-15-year-old

Effectiveness of the 'Healthy School and Drugs' prevention programme on adolescents' substance use: a randomized clustered trial

NARCIS (Netherlands)

Malmberg, M.; Kleinjan, M.; Overbeek, G.J.; Vermulst, A.A.; Monshouwer, K.; Lammers, J.; Vollebergh, W.A.M.; Engels, R.C.M.E.

2014-01-01

Aim To evaluate the effectiveness of the Healthy School and Drugs programme on alcohol, tobacco and marijuana use among Dutch early adolescents. Design Randomized clustered trial with two intervention conditions (i.e. e-learning and integral). Setting General population of 11-15-year-old adolescents

Subthreshold-swing-adjustable tunneling-field-effect-transistor-based random-access memory for nonvolatile operation

Science.gov (United States)

Huh, In; Cheon, Woo Young; Choi, Woo Young

2016-04-01

A subthreshold-swing-adjustable tunneling-field-effect-transistor-based random-access memory (SAT RAM) has been proposed and fabricated for low-power nonvolatile memory applications. The proposed SAT RAM cell demonstrates adjustable subthreshold swing (SS) depending on stored information: small SS in the erase state ("1" state) and large SS in the program state ("0" state). Thus, SAT RAM cells can achieve low read voltage (Vread) with a large memory window in addition to the effective suppression of ambipolar behavior. These unique features of the SAT RAM are originated from the locally stored charge, which modulates the tunneling barrier width (Wtun) of the source-to-channel tunneling junction.

Effects of smartphone diaries and personal dosimeters on behavior in a randomized study of methods to document sunlight exposure

DEFF Research Database (Denmark)

Køster, Brian; Søndergaard, Jens; Nielsen, Jesper Bo

2016-01-01

study. We examined the effects of wearing dosimeters and filling out diaries, measurement period and recall effect on the sun-related behavior in Denmark in 2012.Our sample included 240 participants eligible by smartphone status and who took a vacation during weeks 26-32 in 2012, randomized by gender...

Vapocoolant Spray Effectiveness on Arterial Puncture Pain: A Randomized Controlled Clinical Trial

Directory of Open Access Journals (Sweden)

Shervin Farahmand

2017-02-01

Full Text Available Arterial blood gas (ABG sampling is a painful procedure with no perfect technique for quelling the discomfort. An ideal local anesthesia should be rapid, easy to learn, inexpensive, and noninvasive. This study was aimed to compare pain levels from ABG sampling performed with vapocoolant spray in comparison to placebo. We hypothesized that pretreatment with the vapocoolant would reduce the pain of arterial puncture by at least 1 point on a 10 point verbal numeric scale. We have evaluated the effectiveness of a vapocoolant spray in achieving satisfactory pain control in patients undergoing ABG sampling in this randomized placebo controlled trial. Eighty patients were randomized to 2 groups: group A, who received vapocoolant spray, and group B, who received water spray as placebo (Control group. Puncture and spray application pain was assessed with numerical rating scale (0, the absence of pain; 10, greatest imaginable pain and number of attempts was recorded. The pain score during ABG sampling was not lower in group A compared with group B significantly (4.78±1.761 vs. 4.90±1.837; P:0.945. This study showed that while the spray exerts more application pain, the number of attempts required for ABG sampling was not significantly lower in group A compared with group B (1.38±0.54 vs. 1.53±0.68; P=0.372. Vapocoolant spray was not effective in ABG pain reduction, had milder application pain compared to placebo (P<0.05, but did not reduce sampling attempts. At present, this spray cannot be recommended for arterial puncture anesthesia, and further study on different timing is necessary.

Effect of tai chi versus aerobic exercise for fibromyalgia: comparative effectiveness randomized controlled trial.

Science.gov (United States)

Wang, Chenchen; Schmid, Christopher H; Fielding, Roger A; Harvey, William F; Reid, Kieran F; Price, Lori Lyn; Driban, Jeffrey B; Kalish, Robert; Rones, Ramel; McAlindon, Timothy

2018-03-21

To determine the effectiveness of tai chi interventions compared with aerobic exercise, a current core standard treatment in patients with fibromyalgia, and to test whether the effectiveness of tai chi depends on its dosage or duration. Prospective, randomized, 52 week, single blind comparative effectiveness trial. Urban tertiary care academic hospital in the United States between March 2012 and September 2016. 226 adults with fibromyalgia (as defined by the American College of Rheumatology 1990 and 2010 criteria) were included in the intention to treat analyses: 151 were assigned to one of four tai chi groups and 75 to an aerobic exercise group. Participants were randomly assigned to either supervised aerobic exercise (24 weeks, twice weekly) or one of four classic Yang style supervised tai chi interventions (12 or 24 weeks, once or twice weekly). Participants were followed for 52 weeks. Adherence was rigorously encouraged in person and by telephone. The primary outcome was change in the revised fibromyalgia impact questionnaire (FIQR) scores at 24 weeks compared with baseline. Secondary outcomes included changes of scores in patient's global assessment, anxiety, depression, self efficacy, coping strategies, physical functional performance, functional limitation, sleep, and health related quality of life. FIQR scores improved in all five treatment groups, but the combined tai chi groups improved statistically significantly more than the aerobic exercise group in FIQR scores at 24 weeks (difference between groups=5.5 points, 95% confidence interval 0.6 to 10.4, P=0.03) and several secondary outcomes (patient's global assessment=0.9 points, 0.3 to 1.4, P=0.005; anxiety=1.2 points, 0.3 to 2.1, P=0.006; self efficacy=1.0 points, 0.5 to 1.6, P=0.0004; and coping strategies, 2.6 points, 0.8 to 4.3, P=0.005). Tai chi treatment compared with aerobic exercise administered with the same intensity and duration (24 weeks, twice weekly) had greater benefit (between group

Effects of Aromatherapy Massage on Pregnant Women's Stress and Immune Function: A Longitudinal, Prospective, Randomized Controlled Trial.

Science.gov (United States)

Chen, Pao-Ju; Chou, Cheng-Chen; Yang, Luke; Tsai, Yu-Lun; Chang, Yue-Cune; Liaw, Jen-Jiuan

2017-10-01

This study's aims are to examine the effects of aromatherapy massage on women's stress and immune function during pregnancy. This longitudinal, prospective, randomized controlled trial recruited 52 healthy pregnant women from a prenatal clinic in Taipei using convenience sampling. The participants were randomly assigned to the intervention (n = 24) or control (n = 28) group using Clinstat block randomization. The intervention group received 70 min of aromatherapy massage with 2% lavender essential oil every other week (10 times in total) for 20 weeks; the control group received only routine prenatal care. In both groups, participants' salivary cortisol and immunoglobulin A (IgA) levels were collected before and after the intervention group received aromatherapy massage (every month from 16 to 36 weeks gestation) and were analyzed using enzyme-linked immunosorbent assay. The pregnant women in the intervention group had lower salivary cortisol (p aromatherapy massage than those in the control group, which did not receive massage treatment. Comparing the long-term effects of aromatherapy massage on salivary IgA levels between groups at different times, the study found that the pretest salivary IgA levels at 32 (p = 0.002) and 36 (p aromatherapy massage could significantly decrease stress and enhance immune function in pregnant women. The findings can guide clinicians or midwives in providing aromatherapy massage to women throughout the pregnancy.

Mechanical properties of banana/kenaf fiber-reinforced hybrid polyester composites: Effect of woven fabric and random orientation

International Nuclear Information System (INIS)

Alavudeen, A.; Rajini, N.; Karthikeyan, S.; Thiruchitrambalam, M.; Venkateshwaren, N.

2015-01-01

Highlights: • This paper is presents the fabrications of kenaf/banana fiber hybrid composites. • Effect of weaving pattern and random orientation on mechanical properties was studied. • Role of interfacial adhesion due to chemical modifications were analyzed with the aid of SEM. • Hybridization of kenaf and banana fibers in plain woven composites exhibits maximum mechanical strength. - Abstract: The present work deals with the effect of weaving patterns and random orientatation on the mechanical properties of banana, kenaf and banana/kenaf fiber-reinforced hybrid polyester composites. Composites were prepared using the hand lay-up method with two different weaving patterns, namely, plain and twill type. Of the two weaving patterns, the plain type showed improved tensile properties compared to the twill type in all the fabricated composites. Furthermore, the maximum increase in mechanical strength was observed in the plain woven hybrid composites rather than in randomly oriented composites. This indicates minimum stress development at the interface of composites due to the distribution of load transfer along the fiber direction. Moreover, alkali (NaOH) and sodium lauryl sulfate (SLS) treatments appear to provide an additional improvement in mechanical strength through enhanced interfacial bonding. Morphological studies of fractured mechanical testing samples were performed by scanning electron microscopy (SEM) to understand the de-bonding of fiber/matrix adhesion

Effects of music therapy on intravitreal injections: a randomized clinical trial.

Science.gov (United States)

Chen, Xuejing; Seth, Rajeev K; Rao, Veena S; Huang, John J; Adelman, Ron A

2012-08-01

To investigate the effects of music therapy on anxiety, perceived pain, and satisfaction in patients undergoing intravitreal injections in the outpatient setting. This is a randomized clinical trial. Seventy-three patients were recruited from the retina clinic at 1 institution and randomized into a music therapy (n=37) or control (n=36) group. Prior to injection, patients completed the state portion of the Spielberger State Trait Anxiety Inventory (STAI-S). The music therapy group listened to classical music through computer speakers while waiting for and during the injection. The control group underwent the injection in the same setting without music. Afterward, all patients completed another STAI-S and a satisfaction and pain questionnaire. The main outcome measures were objective anxiety derived from STAI-S scores and subjective pain and anxiety from the post procedure questionnaire. The music therapy group had a greater decrease in anxiety than the control group (P=0.0480). Overall, 73% of all patients requested music for future injections (P=0.0001). The music therapy group (84%) requested music in future injections more frequently than the control group (61%) (P=0.0377). Both groups reported similar levels of pain (P=0.5879). Classical music before and during intravitreal injections decreases anxiety in patients without decreasing pain. Most patients desire to have music during future injections. Music therapy is a low-cost, easy, safe intervention that reduces anxiety during intravitreal injections in the outpatient setting.

Effect of providing free glasses on children's educational outcomes in China: cluster randomized controlled trial.

Science.gov (United States)

Ma, Xiaochen; Zhou, Zhongqiang; Yi, Hongmei; Pang, Xiaopeng; Shi, Yaojiang; Chen, Qianyun; Meltzer, Mirjam E; le Cessie, Saskia; He, Mingguang; Rozelle, Scott; Liu, Yizhi; Congdon, Nathan

2014-09-23

To assess the effect of provision of free glasses on academic performance in rural Chinese children with myopia. Cluster randomized, investigator masked, controlled trial. 252 primary schools in two prefectures in western China, 2012-13. 3177 of 19,934 children in fourth and fifth grades (mean age 10.5 years) with visual acuity 6/12 with glasses. 3052 (96.0%) completed the study. Children were randomized by school (84 schools per arm) to one of three interventions at the beginning of the school year: prescription for glasses only (control group), vouchers for free glasses at a local facility, or free glasses provided in class. Spectacle wear at endline examination and end of year score on a specially designed mathematics test, adjusted for baseline score and expressed in standard deviations. Among 3177 eligible children, 1036 (32.6%) were randomized to control, 988 (31.1%) to vouchers, and 1153 (36.3%) to free glasses in class. All eligible children would benefit from glasses, but only 15% wore them at baseline. At closeout glasses wear was 41% (observed) and 68% (self reported) in the free glasses group, and 26% (observed) and 37% (self reported) in the controls. Effect on test score was 0.11 SD (95% confidence interval 0.01 to 0.21) when the free glasses group was compared with the control group. The adjusted effect of providing free glasses (0.10, 0.002 to 0.19) was greater than parental education (0.03, -0.04 to 0.09) or family wealth (0.01, -0.06 to 0.08). This difference between groups was significant, but was smaller than the prespecified 0.20 SD difference that the study was powered to detect. The provision of free glasses to Chinese children with myopia improves children's performance on mathematics testing to a statistically significant degree, despite imperfect compliance, although the observed difference between groups was smaller than the study was originally designed to detect. Myopia is common and rarely corrected in this setting.Trial Registration

Surface effects of electrode-dependent switching behavior of resistive random-access memory

KAUST Repository

Ke, Jr Jian

2016-09-26

The surface effects of ZnO-based resistive random-access memory (ReRAM) were investigated using various electrodes. Pt electrodes were found to have better performance in terms of the device\\'s switching functionality. A thermodynamic model of the oxygen chemisorption process was proposed to explain this electrode-dependent switching behavior. The temperature-dependent switching voltage demonstrates that the ReRAM devices fabricated with Pt electrodes have a lower activation energy for the chemisorption process, resulting in a better resistive switching performance. These findings provide an in-depth understanding of electrode-dependent switching behaviors and can serve as design guidelines for future ReRAM devices.

Cost-Effectiveness of a Long-Term Internet-Delivered Worksite Health Promotion Programme on Physical Activity and Nutrition: A Cluster Randomized Controlled Trial

Science.gov (United States)

Robroek, Suzan J. W.; Polinder, Suzanne; Bredt, Folef J.; Burdorf, Alex

2012-01-01

This study aims to evaluate the cost-effectiveness of a long-term workplace health promotion programme on physical activity (PA) and nutrition. In total, 924 participants enrolled in a 2-year cluster randomized controlled trial, with departments (n = 74) within companies (n = 6) as the unit of randomization. The intervention was compared with a…

One-year evaluation of the effect of physical therapy for masticatory muscle pain : A randomized controlled trial

NARCIS (Netherlands)

Craane, B.; Dijkstra, P. U.; Stappaerts, K.; De Laat, A.

Physical therapy is widely used to decrease pain and restore function in patients suffering from masticatory muscle pain. Controlled studies on its efficacy are scarce. This study evaluated the 1-year effect of a 6-week physical therapy programme in a single blind, randomized, controlled trial.

Effects of active video games on body composition: a randomized controlled trial.

Science.gov (United States)

Maddison, Ralph; Foley, Louise; Ni Mhurchu, Cliona; Jiang, Yannan; Jull, Andrew; Prapavessis, Harry; Hohepa, Maea; Rodgers, Anthony

2011-07-01

Sedentary activities such as video gaming are independently associated with obesity. Active video games, in which players physically interact with images on screen, may help increase physical activity and improve body composition. The aim of this study was to evaluate the effect of active video games over a 6-mo period on weight, body composition, physical activity, and physical fitness. We conducted a 2-arm, parallel, randomized controlled trial in Auckland, New Zealand. A total of 322 overweight and obese children aged 10-14 y, who were current users of sedentary video games, were randomly assigned at a 1:1 ratio to receive either an active video game upgrade package (intervention, n = 160) or to have no change (control group, n = 162). The primary outcome was the change from baseline in body mass index (BMI; in kg/m(2)). Secondary outcomes were changes in percentage body fat, physical activity, cardiorespiratory fitness, video game play, and food snacking. At 24 wk, the treatment effect on BMI (-0.24; 95% CI: -0.44, -0.05; P = 0.02) favored the intervention group. The change (±SE) in BMI from baseline increased in the control group (0.34 ± 0.08) but remained the same in the intervention group (0.09 ± 0.08). There was also evidence of a reduction in body fat in the intervention group (-0.83%; 95% CI: -1.54%, -0.12%; P = 0.02). The change in daily time spent playing active video games at 24 wk increased (10.03 min; 95% CI: 6.26, 13.81 min; P video games (-9.39 min; 95% CI: -19.38, 0.59 min; P = 0.06). An active video game intervention has a small but definite effect on BMI and body composition in overweight and obese children. This trial was registered in the Australian New Zealand Clinical Trials Registry at http://www.anzctr.org.au/ as ACTRN12607000632493.

Effectiveness of traditional bone setting in chronic neck pain: randomized clinical trial.

Science.gov (United States)

Zaproudina, Nina; Hänninen, Osmo O P; Airaksinen, Olavi

2007-01-01

This study evaluates the effectiveness of traditional bone setting (TBS) in chronic neck pain (cNP) compared with conventional physiotherapy (PT) and massage (M). This was a randomized clinical trial. Working-aged employed subjects with cNP (n = 105; 37 men and 68 women; mean age, 41.5 years) were randomized into TBS, PT, and M groups. Follow-up times were 1, 6, and 12 months after the treatments. Neck pain intensity (visual analog scale), perceived disability (Neck Disability Index [NDI]), and neck spine mobility measurements were used as outcomes. Global assessment was evaluated by the subjects (scale from -1 to +10). Data were analyzed using time (pre and post) by group (TBS, PT and M), 2- way analysis of variance for repeated measures. Neck pain decreased and NDI scores improved in all groups 1 month after the treatment (P better after TBS. Neck spine mobility in rotation movements tended to improve significantly better and the frons-knee distance improved more after TBS. One year later, both NDI and neck pain were significantly better after TBS than in reference groups. A significant improvement was reported by 40% to 45.5% of subjects in the PT and M groups and by 68.6% in the TBS group. Bone setters' ability to communicate and to interact with patients was evaluated significantly higher. In the TBS group, the number of sick days was minimal as was the use of painkillers during 1-year follow-up compared to that in the reference groups. Traditional bone setting, which is a soft manual mobilization technique focusing on the muscles, joints, and ligaments, appears to be effective in cNP. Two thirds of subjects experienced it as beneficial, and it seems to be able to improve disability and pain in patients with cNP. Subjective and partially objective benefits of TBS were found in those patients more than after other interventions, and the effects lasted at least for 1 year.

Effects of exercise programs on falls and mobility in frail and pre-frail older adults: A multicenter randomized controlled trial.

NARCIS (Netherlands)

Faber, M.J.; Bosscher, R.J.; Chin A Paw, M.J.; Wieringen, P. van

2006-01-01

OBJECTIVES: To determine the effects of moderate intensity group-exercise programs on falls, functional performance, and disability in older adults; and to investigate the influence of frailty on these effects. DESIGN: A 20-week, multicenter randomized controlled trial, with 52-week follow-up.

Moderating Effects of Parental Characteristics on the Effectiveness of a Theory of Mind Training for Children with Autism: A Randomized Controlled Trial

Science.gov (United States)

de Veld, Danielle M. J.; Howlin, Patricia; Hoddenbach, Elske; Mulder, Fleur; Wolf, Imke; Koot, Hans M.; Lindauer, Ramón; Begeer, Sander

2017-01-01

This RCT investigated whether the effect of a Theory of Mind (ToM) intervention for children with ASD was moderated by parental education level and employment, family structure, and parental ASD. Children with autism aged 8-13 years (n = 136) were randomized over a waitlist control or treatment condition. At posttest, children in the treatment…

Simple, efficient estimators of treatment effects in randomized trials using generalized linear models to leverage baseline variables.

Science.gov (United States)

Rosenblum, Michael; van der Laan, Mark J

2010-04-01

Models, such as logistic regression and Poisson regression models, are often used to estimate treatment effects in randomized trials. These models leverage information in variables collected before randomization, in order to obtain more precise estimates of treatment effects. However, there is the danger that model misspecification will lead to bias. We show that certain easy to compute, model-based estimators are asymptotically unbiased even when the working model used is arbitrarily misspecified. Furthermore, these estimators are locally efficient. As a special case of our main result, we consider a simple Poisson working model containing only main terms; in this case, we prove the maximum likelihood estimate of the coefficient corresponding to the treatment variable is an asymptotically unbiased estimator of the marginal log rate ratio, even when the working model is arbitrarily misspecified. This is the log-linear analog of ANCOVA for linear models. Our results demonstrate one application of targeted maximum likelihood estimation.

Simple, Efficient Estimators of Treatment Effects in Randomized Trials Using Generalized Linear Models to Leverage Baseline Variables

Science.gov (United States)

Rosenblum, Michael; van der Laan, Mark J.

2010-01-01

Models, such as logistic regression and Poisson regression models, are often used to estimate treatment effects in randomized trials. These models leverage information in variables collected before randomization, in order to obtain more precise estimates of treatment effects. However, there is the danger that model misspecification will lead to bias. We show that certain easy to compute, model-based estimators are asymptotically unbiased even when the working model used is arbitrarily misspecified. Furthermore, these estimators are locally efficient. As a special case of our main result, we consider a simple Poisson working model containing only main terms; in this case, we prove the maximum likelihood estimate of the coefficient corresponding to the treatment variable is an asymptotically unbiased estimator of the marginal log rate ratio, even when the working model is arbitrarily misspecified. This is the log-linear analog of ANCOVA for linear models. Our results demonstrate one application of targeted maximum likelihood estimation. PMID:20628636

Effectiveness of massage therapy as co-adjuvant treatment to exercise in osteoarthritis of the knee: a randomized control trial.

Science.gov (United States)

Cortés Godoy, Virginia; Gallego Izquierdo, Tomás; Lázaro Navas, Irene; Pecos Martín, Daniel

2014-01-01

The effectiveness of exercise therapy in the treatment of osteoarthritis of the knee (KOA) is widely evidenced. The current study aims to compare the effectiveness of massage therapy as a co-adjuvant treatment for KOA. A blind, randomized controlled trial design was used. Eighteen women were randomly allocated to two different groups. Group A was treated with massage therapy and an exercise program, and Group B was treated with the exercise program alone. The intervention lasted for 6 weeks. Outcomes were assessed using a verbal analogue scale (VAS), the WOMAC index, and the Get-Up and Go test. Baseline, post-treatment, and 1- and 3- month follow-up data were collected. Values were considered statistically significant at a p massage therapy may lead to clinical improvement in patients with KOA. The use of massage therapy combined with exercise as a treatment for gonarthrosis does not seem to have any beneficial effects.

Micro-Randomized Trials: An Experimental Design for Developing Just-in-Time Adaptive Interventions

Science.gov (United States)

Klasnja, Predrag; Hekler, Eric B.; Shiffman, Saul; Boruvka, Audrey; Almirall, Daniel; Tewari, Ambuj; Murphy, Susan A.

2015-01-01

Objective This paper presents an experimental design, the micro-randomized trial, developed to support optimization of just-in-time adaptive interventions (JITAIs). JITAIs are mHealth technologies that aim to deliver the right intervention components at the right times and locations to optimally support individuals’ health behaviors. Micro-randomized trials offer a way to optimize such interventions by enabling modeling of causal effects and time-varying effect moderation for individual intervention components within a JITAI. Methods The paper describes the micro-randomized trial design, enumerates research questions that this experimental design can help answer, and provides an overview of the data analyses that can be used to assess the causal effects of studied intervention components and investigate time-varying moderation of those effects. Results Micro-randomized trials enable causal modeling of proximal effects of the randomized intervention components and assessment of time-varying moderation of those effects. Conclusions Micro-randomized trials can help researchers understand whether their interventions are having intended effects, when and for whom they are effective, and what factors moderate the interventions’ effects, enabling creation of more effective JITAIs. PMID:26651463

Fluctuation theory for radiative transfer in random media

International Nuclear Information System (INIS)

Bal, Guillaume; Jing Wenjia

2011-01-01

We consider the effect of small scale random fluctuations of the constitutive coefficients on boundary measurements of solutions to radiative transfer equations. As the correlation length of the random oscillations tends to zero, the transport solution is well approximated by a deterministic, averaged, solution. In this paper, we analyze the random fluctuations to the averaged solution, which may be interpreted as a central limit correction to homogenization. With the inverse transport problem in mind, we characterize the random structure of the singular components of the transport measurement operator. In regimes of moderate scattering, such components provide stable reconstructions of the constitutive parameters in the transport equation. We show that the random fluctuations strongly depend on the decorrelation properties of the random medium.

Exercise, Manual Therapy, and Booster Sessions in Knee Osteoarthritis: Cost-Effectiveness Analysis From a Multicenter Randomized Controlled Trial.

Science.gov (United States)

Bove, Allyn M; Smith, Kenneth J; Bise, Christopher G; Fritz, Julie M; Childs, John; Brennan, Gerard P; Abbott, J Haxby; Fitzgerald, G Kelley

2018-01-01

Limited information exists regarding the cost-effectiveness of rehabilitation strategies for individuals with knee osteoarthritis (OA). The study objective was to compare the cost-effectiveness of 4 different combinations of exercise, manual therapy, and booster sessions for individuals with knee OA. This economic evaluation involved a cost-effectiveness analysis performed alongside a multicenter randomized controlled trial. The study took place in Pittsburgh, Pennsylvania; Salt Lake City, Utah; and San Antonio, Texas. The study participants were 300 individuals taking part in a randomized controlled trial investigating various physical therapy strategies for knee OA. Participants were randomized into 4 treatment groups: exercise only (EX), exercise plus booster sessions (EX+B), exercise plus manual therapy (EX+MT), and exercise plus manual therapy and booster sessions (EX+MT+B). For the 2-year base case scenario, a Markov model was constructed using the United States societal perspective and a 3% discount rate for costs and quality-adjusted life years (QALYs). Incremental cost-effectiveness ratios were calculated to compare differences in cost per QALY gained among the 4 treatment strategies. In the 2-year analysis, booster strategies (EX+MT+B and EX+B) dominated no-booster strategies, with both lower health care costs and greater effectiveness. EX+MT+B had the lowest total health care costs. EX+B cost ${\\$}$1061 more and gained 0.082 more QALYs than EX+MT+B, for an incremental cost-effectiveness ratio of ${\\$}$12,900/QALY gained. The small number of total knee arthroplasty surgeries received by individuals in this study made the assessment of whether any particular strategy was more successful at delaying or preventing surgery in individuals with knee OA difficult. Spacing exercise-based physical therapy sessions over 12 months using periodic booster sessions was less costly and more effective over 2 years than strategies not containing booster sessions for

Effectiveness of Wii-based rehabilitation in stroke: A randomized controlled study

OpenAIRE

Ayça Utkan Karasu; Elif Balevi Batur; Gülçin Kaymak Karataş

2018-01-01

Objective: To investigate the efficacy of Nintendo Wii Fit®-based balance rehabilitation as an adjunc-tive therapy to conventional rehabilitation in stroke patients. Methods: During the study period, 70 stroke patients were evaluated. Of these, 23 who met the study criteria were randomly assigned to either the experimental group (n = 12) or the control group (n = 11) by block randomization. Primary outcome measures were Berg Balance Scale, Functional Reach Test, Postural Asses...

A Double-Blind, Randomized Pilot Trial of Chromium Picolinate for Overweight Individuals with Binge-Eating Disorder: Effects on Glucose Regulation.

Science.gov (United States)

Sala, Margarita; Breithaupt, Lauren; Bulik, Cynthia M; Hamer, Robert M; La Via, Maria C; Brownley, Kimberly A

2017-03-04

Chromium treatment has been shown to improve glucose regulation in some populations. The purpose of this study was to evaluate whether chromium picolinate (CrPic) supplementation improves glucose regulation in overweight individuals with binge-eating disorder (BED). In this double-blinded randomized pilot trial, participants (N = 24) were randomized to high (HIGH, 1000 mcg/day, n = 8) or moderate (MOD, 600 mcg/day, n = 9) dose of CrPic or placebo (PL, n = 7) for 6 months. Participants completed an oral glucose tolerance test (OGTT) at baseline, 3 months, and 6 months. Fixed effects models were used to estimate mean change in glucose area under the curve (AUC), insulin AUC , and insulin sensitivity index (ISI). Results revealed a significant group and time interaction (p < 0.04) for glucose AUC , with glucose AUC increasing significantly in the PL group (p < 0.02) but decreasing significantly in the MOD group (p < 0.03) at 6 months. Insulin AUC increased significantly over time (main effect, p < 0.02), whereas ISI decreased significantly over time (main effect, p < 0.03). As anticipated, a moderate dose of CrPic was associated with improved glycemic control, whereas PL was associated with decreased glycemic control. It was unexpected that the improved glycemic control seen in the MOD dose group was not seen in the HIGH dose group. However, although participants randomized to the HIGH dose group did not have improved glycemic control, they had better glycemic control than participants randomized to the PL group. These findings support the need for larger trials.