Significance of Random Bladder Biopsies in Non-Muscle Invasive Bladder Cancer

PubMed Central

Kumano, Masafumi; Miyake, Hideaki; Nakano, Yuzo; Fujisawa, Masato

2013-01-01

Background/Aims To evaluate retrospectively the clinical outcome of random bladder biopsies in patients with non-muscle invasive bladder cancer (NMIBC) undergoing transurethral resection (TUR). Patients and Method This study included 234 consecutive patients with NMIBC who underwent random biopsies from normal-appearing urothelium of the bladder, including the anterior wall, posterior wall, right wall, left wall, dome, trigone and/or prostatic urethra, during TUR. Result Thirty-seven patients (15.8%) were diagnosed by random biopsies as having urothelial cancer. Among several factors available prior to TUR, preoperative urinary cytology appeared to be independently related to the detection of urothelial cancer in random biopsies on multivariate analysis. Urinary cytology prior to TUR gave 50.0% sensitivity, 91.7% specificity, 56.8% positive predictive value and 89.3% negative predictive value for predicting the findings of the random biopsies. Conclusion Biopsies of normal-appearing urothelium resulted in the additional detection of urothelial cancer in a definite proportion of NMIBC patients, and it remains difficult to find a reliable alternative to random biopsies. Collectively, these findings suggest that it would be beneficial to perform random biopsies as part of the routine management of NMIBC. PMID:24917759

Evaluation of Classifier Performance for Multiclass Phenotype Discrimination in Untargeted Metabolomics.

PubMed

Trainor, Patrick J; DeFilippis, Andrew P; Rai, Shesh N

2017-06-21

Statistical classification is a critical component of utilizing metabolomics data for examining the molecular determinants of phenotypes. Despite this, a comprehensive and rigorous evaluation of the accuracy of classification techniques for phenotype discrimination given metabolomics data has not been conducted. We conducted such an evaluation using both simulated and real metabolomics datasets, comparing Partial Least Squares-Discriminant Analysis (PLS-DA), Sparse PLS-DA, Random Forests, Support Vector Machines (SVM), Artificial Neural Network, k -Nearest Neighbors ( k -NN), and Naïve Bayes classification techniques for discrimination. We evaluated the techniques on simulated data generated to mimic global untargeted metabolomics data by incorporating realistic block-wise correlation and partial correlation structures for mimicking the correlations and metabolite clustering generated by biological processes. Over the simulation studies, covariance structures, means, and effect sizes were stochastically varied to provide consistent estimates of classifier performance over a wide range of possible scenarios. The effects of the presence of non-normal error distributions, the introduction of biological and technical outliers, unbalanced phenotype allocation, missing values due to abundances below a limit of detection, and the effect of prior-significance filtering (dimension reduction) were evaluated via simulation. In each simulation, classifier parameters, such as the number of hidden nodes in a Neural Network, were optimized by cross-validation to minimize the probability of detecting spurious results due to poorly tuned classifiers. Classifier performance was then evaluated using real metabolomics datasets of varying sample medium, sample size, and experimental design. We report that in the most realistic simulation studies that incorporated non-normal error distributions, unbalanced phenotype allocation, outliers, missing values, and dimension reduction, classifier performance (least to greatest error) was ranked as follows: SVM, Random Forest, Naïve Bayes, sPLS-DA, Neural Networks, PLS-DA and k -NN classifiers. When non-normal error distributions were introduced, the performance of PLS-DA and k -NN classifiers deteriorated further relative to the remaining techniques. Over the real datasets, a trend of better performance of SVM and Random Forest classifier performance was observed.

[Tolerance and adequacy of a 100% lactose infant formula. A controlled randomized double-blind study].

PubMed

Girardet, J-P; Fournier, V; Bakhache, P; Beck, L; Kempf, C; Lachambre, E

2012-07-01

Lactose has beneficial nutritional effects in infancy, particularly on calcium retention and on Bifidobacterium colon microflora development. The objective of this controlled, prospective, randomized double-blind study was to assess the adequacy and safety of an infant formula containing only lactose as carbohydrate, as compared to a usual formula. Healthy non-breast-fed infants aged under 7 days were randomized to be fed exclusively with a conventional formula containing lactose (9.6 g/100 kcal) and maltodextrin (1.6 g/100 kcal) or the isocaloric-isoprotein study formula containing 100% lactose (11.2 g/100 kcal) for 120 days. Primary outcome was daily weight gain at D0 and D120. Weight, length, body mass index, formula consumption, tolerance, and safety were assessed monthly. The non-inferiority of the study formula was rejected if the difference in weight gain was higher than 2.5 g/day in the control group. One hundred and seventy-eight infants were enrolled. Mean daily weight gain in the study group differed by 0.71 g/day (95% CI: -2.23; 0.82) indicating the non-inferiority of the study formula. Growth was normal and similar in the two groups, but formula intake was decreased in the study group, leading to a decrease in energy and protein intakes. Tolerance was good and adverse events did not differ between the two groups. The 100% lactose study infant formula was safe and non-inferior to a conventional formula in ensuring normal growth during the first 4 months of life. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

Characterization of cancer and normal tissue fluorescence through wavelet transform and singular value decomposition

NASA Astrophysics Data System (ADS)

Gharekhan, Anita H.; Biswal, Nrusingh C.; Gupta, Sharad; Pradhan, Asima; Sureshkumar, M. B.; Panigrahi, Prasanta K.

2008-02-01

The statistical and characteristic features of the polarized fluorescence spectra from cancer, normal and benign human breast tissues are studied through wavelet transform and singular value decomposition. The discrete wavelets enabled one to isolate high and low frequency spectral fluctuations, which revealed substantial randomization in the cancerous tissues, not present in the normal cases. In particular, the fluctuations fitted well with a Gaussian distribution for the cancerous tissues in the perpendicular component. One finds non-Gaussian behavior for normal and benign tissues' spectral variations. The study of the difference of intensities in parallel and perpendicular channels, which is free from the diffusive component, revealed weak fluorescence activity in the 630nm domain, for the cancerous tissues. This may be ascribable to porphyrin emission. The role of both scatterers and fluorophores in the observed minor intensity peak for the cancer case is experimentally confirmed through tissue-phantom experiments. Continuous Morlet wavelet also highlighted this domain for the cancerous tissue fluorescence spectra. Correlation in the spectral fluctuation is further studied in different tissue types through singular value decomposition. Apart from identifying different domains of spectral activity for diseased and non-diseased tissues, we found random matrix support for the spectral fluctuations. The small eigenvalues of the perpendicular polarized fluorescence spectra of cancerous tissues fitted remarkably well with random matrix prediction for Gaussian random variables, confirming our observations about spectral fluctuations in the wavelet domain.

Prevalence of isolated non-albumin proteinuria in the US population tested for both, urine total protein and urine albumin: An unexpected discovery.

PubMed

Katayev, Alexander; Zebelman, Arthur M; Sharp, Thomas M; Samantha Flynn; Bernstein, Richard K

2017-04-01

Isolated non-albumin proteinuria (NAP) is a condition when urine total protein concentrations are elevated without elevation of urine albumin. The prevalence of NAP in the US population tested for both, urine total protein and albumin was assessed in this study. The database of a US nationwide laboratory network was queried for test results when random urine albumin was ordered together with urine total protein and also when timed 24-hour urine albumin was ordered together with urine total protein. The total prevalence of NAP in the US population tested for both, urine total protein and albumin was calculated for patient groups having normal and low-normal urine albumin (random and timed) with elevated and severely increased urine total protein (random and timed). Also, the prevalence of NAP was calculated for patients with normal urine albumin to assess the probability of missing proteinuria if only urine albumin is measured. The prevalence of NAP in the random samples group was 10.1% (15.2% for females and 4.7% for males). Among patients with normal random albumin, there were 20.0% (27.3% of females and 10.7% of males) patients with NAP. The prevalence of NAP in the timed samples group was 24.6% (29.8% for females and 18.5% for males). Among patients with normal timed urine albumin, there were 36.2% (40.0% of females and 30.8% of males) patients with NAP. There was a strong positive association with female gender and NAP in most patients groups. Testing for only urine (micro)albumin can miss up to 40% of females and 30.8% of males with gross proteinuria. Copyright © 2016 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Evaluation of a reduced nicotine product standard: moderating effects of and impact on cannabis use*

PubMed Central

Pacek, Lauren R.; Vandrey, Ryan; Dermody, Sarah S.; Denlinger, Rachel L.; Lemieux, Andrine; Tidey, Jennifer W.; McClernon, F. Joseph; Bangdiwala, Ananta S.; Drobes, David J.; al'Absi, Mustafa; Strasser, Andrew A.; Koopmeiners, Joseph S.; Hatsukami, Dorothy K.; Donny, Eric C.

2016-01-01

Introduction The Family Smoking Prevention and Tobacco Control Act authorized the FDA to reduce the nicotine content in cigarettes. Research is needed to guide proposed regulations, including evaluation of consequences to public health. This study evaluated how a reduced nicotine product standard might be moderated by and impact cannabis use. Methods Secondary analysis of a controlled clinical trial examining the effects of nicotine content in cigarettes in adult daily smokers. Linear regression assessed whether baseline cannabis use moderated behavioral, subjective, or physiological effects of smoking very low nicotine content (VLNC) versus normal nicotine content (NNC) cigarettes. Repeated measures analysis of associations between nicotine condition and prevalence and frequency of cannabis use was completed using generalized estimating equations (GEE). Results Among cannabis users and non-users, smokers randomized to VLNC cigarettes reported lower nicotine dependence, cigarettes per day, biomarkers of nicotine exposure, and craving compared to smokers randomized to NNC cigarettes. Non-cannabis using smokers randomized to VLNC cigarettes also reported lower smoking dependence motives and had lower tobacco-specific nitrosamine exposure and total puff volume versus smokers randomized to NNC cigarettes. For cannabis users, smokers randomized to VLNC cigarettes reported decreased positive affect. Cannabis use did not moderate most effects of VLNC cigarettes. VLNC cigarette use did not impact the prevalence or frequency of cannabis use. Discussion Findings provide evidence that nicotine reduction in cigarettes could have beneficial effects on cigarette smoking regardless of cannabis use. Results suggest that transitioning to VLNC cigarettes is unlikely to alter current rates of cannabis use. PMID:27590743

Evaluation of a reduced nicotine product standard: Moderating effects of and impact on cannabis use.

PubMed

Pacek, Lauren R; Vandrey, Ryan; Dermody, Sarah S; Denlinger-Apte, Rachel L; Lemieux, Andrine; Tidey, Jennifer W; McClernon, F Joseph; Bangdiwala, Ananta S; Drobes, David J; al'Absi, Mustafa; Strasser, Andrew A; Koopmeiners, Joseph S; Hatsukami, Dorothy K; Donny, Eric C

2016-10-01

The Family Smoking Prevention and Tobacco Control Act authorized the FDA to reduce the nicotine content in cigarettes. Research is needed to guide proposed regulations, including evaluation of consequences to public health. This study evaluated how a reduced nicotine product standard might be moderated by and impact cannabis use. Secondary analysis of a controlled clinical trial examining the effects of nicotine content in cigarettes in adult daily smokers. Linear regression assessed whether baseline cannabis use moderated behavioral, subjective, or physiological effects of smoking very low nicotine content (VLNC) versus normal nicotine content (NNC) cigarettes. Repeated measures analysis of associations between nicotine condition and prevalence and frequency of cannabis use was completed using generalized estimating equations (GEE). Cannabis use did not moderate most of the following effects of VLNC cigarettes: Among cannabis users and non-users, smokers randomized to VLNC cigarettes reported lower nicotine dependence, cigarettes per day, biomarkers of nicotine exposure, and craving compared to smokers randomized to NNC cigarettes. Non-cannabis using smokers randomized to VLNC cigarettes also reported lower smoking dependence motives and had lower tobacco-specific nitrosamine exposure and total puff volume versus smokers randomized to NNC cigarettes. For cannabis users, smokers randomized to VLNC cigarettes reported decreased positive affect. VLNC cigarette use did not impact the prevalence or frequency of cannabis use. Findings provide evidence that nicotine reduction in cigarettes could have beneficial effects on cigarette smoking regardless of cannabis use. Results suggest that transitioning to VLNC cigarettes is unlikely to alter current rates of cannabis use. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Log-gamma linear-mixed effects models for multiple outcomes with application to a longitudinal glaucoma study

PubMed Central

Zhang, Peng; Luo, Dandan; Li, Pengfei; Sharpsten, Lucie; Medeiros, Felipe A.

2015-01-01

Glaucoma is a progressive disease due to damage in the optic nerve with associated functional losses. Although the relationship between structural and functional progression in glaucoma is well established, there is disagreement on how this association evolves over time. In addressing this issue, we propose a new class of non-Gaussian linear-mixed models to estimate the correlations among subject-specific effects in multivariate longitudinal studies with a skewed distribution of random effects, to be used in a study of glaucoma. This class provides an efficient estimation of subject-specific effects by modeling the skewed random effects through the log-gamma distribution. It also provides more reliable estimates of the correlations between the random effects. To validate the log-gamma assumption against the usual normality assumption of the random effects, we propose a lack-of-fit test using the profile likelihood function of the shape parameter. We apply this method to data from a prospective observation study, the Diagnostic Innovations in Glaucoma Study, to present a statistically significant association between structural and functional change rates that leads to a better understanding of the progression of glaucoma over time. PMID:26075565

Effects of modafinil on attention performance, short-term memory and executive function in university students: a randomized trial.

PubMed

Fernández, Alejandro; Mascayano, Franco; Lips, Walter; Painel, Andrés; Norambuena, Jonathan; Madrid, Eva

2015-06-30

Modafinil is a drug developed and used for the treatment of excessive lethargy. Even though very effective for sleep disorders, it is still controversial whether modafinil can improve performance in high-order cognitive processes such as memory and executive function. This randomized, double-blind, placebo-controlled, crossover trial was designed to evaluate the effect of modafinil (compared to placebo) on the cognitive functions of healthy students. 160 volunteers were recruited and allocated randomly to modafinil or placebo group, and were assessed using the Stroop Test, BCET test and Digit span test. We found a significant difference in favor of modafinil compared to placebo in the proportion of correct answers of Stroop Test in congruent situation. A significant shorter latency of modafinil group in the incongruent situation of Stroop test was also found. No differences were found in Digit Span, or BCET tests. The study demonstrated that modafinil does not enhance the global cognitive performance of healthy non-sleep deprived students, except regarding non-demanding tasks. In particular, this drug does not seem to have positive effects on mental processes that sustain studying tasks in the college population under normal conditions. We expect these findings to demystify the use of this drug and help decision making concerning pharmacological public policies.

Detecting and correcting for publication bias in meta-analysis - A truncated normal distribution approach.

PubMed

Zhu, Qiaohao; Carriere, K C

2016-01-01

Publication bias can significantly limit the validity of meta-analysis when trying to draw conclusion about a research question from independent studies. Most research on detection and correction for publication bias in meta-analysis focus mainly on funnel plot-based methodologies or selection models. In this paper, we formulate publication bias as a truncated distribution problem, and propose new parametric solutions. We develop methodologies of estimating the underlying overall effect size and the severity of publication bias. We distinguish the two major situations, in which publication bias may be induced by: (1) small effect size or (2) large p-value. We consider both fixed and random effects models, and derive estimators for the overall mean and the truncation proportion. These estimators will be obtained using maximum likelihood estimation and method of moments under fixed- and random-effects models, respectively. We carried out extensive simulation studies to evaluate the performance of our methodology, and to compare with the non-parametric Trim and Fill method based on funnel plot. We find that our methods based on truncated normal distribution perform consistently well, both in detecting and correcting publication bias under various situations.

Multilevel mixed effects parametric survival models using adaptive Gauss-Hermite quadrature with application to recurrent events and individual participant data meta-analysis.

PubMed

Crowther, Michael J; Look, Maxime P; Riley, Richard D

2014-09-28

Multilevel mixed effects survival models are used in the analysis of clustered survival data, such as repeated events, multicenter clinical trials, and individual participant data (IPD) meta-analyses, to investigate heterogeneity in baseline risk and covariate effects. In this paper, we extend parametric frailty models including the exponential, Weibull and Gompertz proportional hazards (PH) models and the log logistic, log normal, and generalized gamma accelerated failure time models to allow any number of normally distributed random effects. Furthermore, we extend the flexible parametric survival model of Royston and Parmar, modeled on the log-cumulative hazard scale using restricted cubic splines, to include random effects while also allowing for non-PH (time-dependent effects). Maximum likelihood is used to estimate the models utilizing adaptive or nonadaptive Gauss-Hermite quadrature. The methods are evaluated through simulation studies representing clinically plausible scenarios of a multicenter trial and IPD meta-analysis, showing good performance of the estimation method. The flexible parametric mixed effects model is illustrated using a dataset of patients with kidney disease and repeated times to infection and an IPD meta-analysis of prognostic factor studies in patients with breast cancer. User-friendly Stata software is provided to implement the methods. Copyright © 2014 John Wiley & Sons, Ltd.

Efficacy of Miswak toothpaste and mouthwash on cariogenic bacteria

PubMed Central

Al-Dabbagh, Samim A.; Qasim, Huda J.; Al-Derzi, Nadia A.

2016-01-01

Objectives: To evaluate the efficacy of Salvadora persica (Miswak) products on cariogenic bacteria in comparison with ordinary toothpaste. Methods: The study was conducted in Zakho city, Kurdistan region, Iraq during the period from October 2013 to January 2014. A randomized controlled clinical trial of 40 students randomly allocated into 4 groups. They were instructed to use Mismark toothpaste, Miswak mouthwash, and ordinary toothpaste with water or with normal saline. Salivary samples were collected at 3-time intervals: before, immediately after use, and after 2 weeks of use. The effect of each method on Streptococcus mutans and Lactobacilli was evaluated by using caries risk test. Results: One-way repeated measure analysis of variance (ANOVA), one-way ANOVA, and least significant difference tests were used. Miswak wash has a significant reduction effect on both bacteria immediately and after 2 weeks of use. Miswak paste has a similar effect on Lactobacilli, while Streptococcus mutans showed a significant decrease only after 2 weeks of use. Ordinary paste showed a non significant effect on both bacteria at both time intervals; while the addition of normal saline showed a significant effect on both bacteria only after 2 weeks of use. Conclusion: Miswak products, especially mouth wash, were more effective in reducing the growth of cariogenic bacteria than ordinary toothpaste. PMID:27570858

Exploratory Study of 4D Versus 3D Robust Optimization in Intensity-Modulated Proton Therapy for Lung Cancer

PubMed Central

Liu, Wei; Schild, Steven E.; Chang, Joe Y.; Liao, Zhongxing; Chang, Yu-Hui; Wen, Zhifei; Shen, Jiajian; Stoker, Joshua B.; Ding, Xiaoning; Hu, Yanle; Sahoo, Narayan; Herman, Michael G.; Vargas, Carlos; Keole, Sameer; Wong, William; Bues, Martin

2015-01-01

Background To compare the impact of uncertainties and interplay effect on 3D and 4D robustly optimized intensity-modulated proton therapy (IMPT) plans for lung cancer in an exploratory methodology study. Methods IMPT plans were created for 11 non-randomly selected non-small-cell lung cancer (NSCLC) cases: 3D robustly optimized plans on average CTs with internal gross tumor volume density overridden to irradiate internal target volume, and 4D robustly optimized plans on 4D CTs to irradiate clinical target volume (CTV). Regular fractionation (66 Gy[RBE] in 33 fractions) were considered. In 4D optimization, the CTV of individual phases received non-uniform doses to achieve a uniform cumulative dose. The root-mean-square-dose volume histograms (RVH) measured the sensitivity of the dose to uncertainties, and the areas under the RVH curve (AUCs) were used to evaluate plan robustness. Dose evaluation software modeled time-dependent spot delivery to incorporate interplay effect with randomized starting phases of each field per fraction. Dose-volume histogram indices comparing CTV coverage, homogeneity, and normal tissue sparing were evaluated using Wilcoxon signed-rank test. Results 4D robust optimization plans led to smaller AUC for CTV (14.26 vs. 18.61 (p=0.001), better CTV coverage (Gy[RBE]) [D95% CTV: 60.6 vs 55.2 (p=0.001)], and better CTV homogeneity [D5%–D95% CTV: 10.3 vs 17.7 (p=0.002)] in the face of uncertainties. With interplay effect considered, 4D robust optimization produced plans with better target coverage [D95% CTV: 64.5 vs 63.8 (p=0.0068)], comparable target homogeneity, and comparable normal tissue protection. The benefits from 4D robust optimization were most obvious for the 2 typical stage III lung cancer patients. Conclusions Our exploratory methodology study showed that, compared to 3D robust optimization, 4D robust optimization produced significantly more robust and interplay-effect-resistant plans for targets with comparable dose distributions for normal tissues. A further study with a larger and more realistic patient population is warranted to generalize the conclusions. PMID:26725727

Clinical efficacy comparison of Saccharomyces boulardii and yogurt fluid in acute non-bloody diarrhea in children: a randomized, controlled, open label study.

PubMed

Eren, Makbule; Dinleyici, Ener C; Vandenplas, Yvan

2010-03-01

The purpose of this trial is to evaluate the clinical efficacy and cost/effectiveness of Saccharomyces boulardii compared with yogurt fluid (YF) in acute non-bloody diarrhea in children. This randomized, prospective open-label clinical trial includes 55 children (36 boys, 19 girls; mean age 21.2 +/- 28.2 months). Group A (N = 28) received lyophilized S. boulardii and group B (N = 27) received YF. The duration of diarrhea was shorter with S. boulardii but the hospital stay was reduced with YF, although these differences were not significant. However, diarrhea had resolved in significantly more children on day 3 in the S. boulardii group (48.5% versus 25.5%; P < 0.05). In outpatient cases, yogurt treatment was cheaper than S. boulardii whereas in hospitalized patients, treatment cost was similar. In conclusion, the effect of daily freshly prepared YF was comparable to S. boulardii in the treatment of acute non-bloody diarrhea in children. The duration of diarrhea was shorter in the S. boulardii group, expressed as a significantly higher number of patients with normal stools on day 3.

Clinical Efficacy Comparison of Saccharomyces boulardii and Yogurt Fluid in Acute Non-Bloody Diarrhea in Children: A Randomized, Controlled, Open Label Study

PubMed Central

Eren, Makbule; Dinleyici, Ener C.; Vandenplas, Yvan

2010-01-01

The purpose of this trial is to evaluate the clinical efficacy and cost/effectiveness of Saccharomyces boulardii compared with yogurt fluid (YF) in acute non-bloody diarrhea in children. This randomized, prospective open-label clinical trial includes 55 children (36 boys, 19 girls; mean age 21.2 ± 28.2 months). Group A (N = 28) received lyophilized S. boulardii and group B (N = 27) received YF. The duration of diarrhea was shorter with S. boulardii but the hospital stay was reduced with YF, although these differences were not significant. However, diarrhea had resolved in significantly more children on day 3 in the S. boulardii group (48.5% versus 25.5%; P < 0.05). In outpatient cases, yogurt treatment was cheaper than S. boulardii whereas in hospitalized patients, treatment cost was similar. In conclusion, the effect of daily freshly prepared YF was comparable to S. boulardii in the treatment of acute non-bloody diarrhea in children. The duration of diarrhea was shorter in the S. boulardii group, expressed as a significantly higher number of patients with normal stools on day 3. PMID:20207879

Derivation of a Multiparameter Gamma Model for Analyzing the Residence-Time Distribution Function for Nonideal Flow Systems as an Alternative to the Advection-Dispersion Equation

DOE PAGES

Embry, Irucka; Roland, Victor; Agbaje, Oluropo; ...

2013-01-01

A new residence-time distribution (RTD) function has been developed and applied to quantitative dye studies as an alternative to the traditional advection-dispersion equation (AdDE). The new method is based on a jointly combined four-parameter gamma probability density function (PDF). The gamma residence-time distribution (RTD) function and its first and second moments are derived from the individual two-parameter gamma distributions of randomly distributed variables, tracer travel distance, and linear velocity, which are based on their relationship with time. The gamma RTD function was used on a steady-state, nonideal system modeled as a plug-flow reactor (PFR) in the laboratory to validate themore » effectiveness of the model. The normalized forms of the gamma RTD and the advection-dispersion equation RTD were compared with the normalized tracer RTD. The normalized gamma RTD had a lower mean-absolute deviation (MAD) (0.16) than the normalized form of the advection-dispersion equation (0.26) when compared to the normalized tracer RTD. The gamma RTD function is tied back to the actual physical site due to its randomly distributed variables. The results validate using the gamma RTD as a suitable alternative to the advection-dispersion equation for quantitative tracer studies of non-ideal flow systems.« less

Effects of Non-Normal Outlier-Prone Error Distribution on Kalman Filter Track

DTIC Science & Technology

1991-09-01

other possibilities exist. For example the GST (Generic Statistical Tracker) uses four motion models [Ref. 41. The GST keeps track of both the target...1.011 + + + 3.113 1.291 4 Although this procedure is not easily statistically interpretable, it was used for the sake of comparison with the other... TRANSITOR TARGET’ WRITE(6,*)’ 3 SECOND ORDER GAUSS MARKOV TARGET’ WRITE(6,*)’ 4 RANDOM TOUR TARGET’ READ(6,*) CHOICE IF((CHOICE.LT.1).OR.(CHOICE.GT.4

Spin-transfer torque magnetoresistive random-access memory technologies for normally off computing (invited)

NASA Astrophysics Data System (ADS)

Ando, K.; Fujita, S.; Ito, J.; Yuasa, S.; Suzuki, Y.; Nakatani, Y.; Miyazaki, T.; Yoda, H.

2014-05-01

Most parts of present computer systems are made of volatile devices, and the power to supply them to avoid information loss causes huge energy losses. We can eliminate this meaningless energy loss by utilizing the non-volatile function of advanced spin-transfer torque magnetoresistive random-access memory (STT-MRAM) technology and create a new type of computer, i.e., normally off computers. Critical tasks to achieve normally off computers are implementations of STT-MRAM technologies in the main memory and low-level cache memories. STT-MRAM technology for applications to the main memory has been successfully developed by using perpendicular STT-MRAMs, and faster STT-MRAM technologies for applications to the cache memory are now being developed. The present status of STT-MRAMs and challenges that remain for normally off computers are discussed.

Non-intrusive head movement analysis of videotaped seizures of epileptic origin.

PubMed

Mandal, Bappaditya; Eng, How-Lung; Lu, Haiping; Chan, Derrick W S; Ng, Yen-Ling

2012-01-01

In this work we propose a non-intrusive video analytic system for patient's body parts movement analysis in Epilepsy Monitoring Unit. The system utilizes skin color modeling, head/face pose template matching and face detection to analyze and quantify the head movements. Epileptic patients' heads are analyzed holistically to infer seizure and normal random movements. The patient does not require to wear any special clothing, markers or sensors, hence it is totally non-intrusive. The user initializes the person-specific skin color and selects few face/head poses in the initial few frames. The system then tracks the head/face and extracts spatio-temporal features. Support vector machines are then used on these features to classify seizure-like movements from normal random movements. Experiments are performed on numerous long hour video sequences captured in an Epilepsy Monitoring Unit at a local hospital. The results demonstrate the feasibility of the proposed system in pediatric epilepsy monitoring and seizure detection.

General Framework for Effect Sizes in Cluster Randomized Experiments

ERIC Educational Resources Information Center

VanHoudnos, Nathan

2016-01-01

Cluster randomized experiments are ubiquitous in modern education research. Although a variety of modeling approaches are used to analyze these data, perhaps the most common methodology is a normal mixed effects model where some effects, such as the treatment effect, are regarded as fixed, and others, such as the effect of group random assignment…

A Bayesian Nonparametric Meta-Analysis Model

ERIC Educational Resources Information Center

Karabatsos, George; Talbott, Elizabeth; Walker, Stephen G.

2015-01-01

In a meta-analysis, it is important to specify a model that adequately describes the effect-size distribution of the underlying population of studies. The conventional normal fixed-effect and normal random-effects models assume a normal effect-size population distribution, conditionally on parameters and covariates. For estimating the mean overall…

On the extreme value statistics of normal random matrices and 2D Coulomb gases: Universality and finite N corrections

NASA Astrophysics Data System (ADS)

Ebrahimi, R.; Zohren, S.

2018-03-01

In this paper we extend the orthogonal polynomials approach for extreme value calculations of Hermitian random matrices, developed by Nadal and Majumdar (J. Stat. Mech. P04001 arXiv:1102.0738), to normal random matrices and 2D Coulomb gases in general. Firstly, we show that this approach provides an alternative derivation of results in the literature. More precisely, we show convergence of the rescaled eigenvalue with largest modulus of a normal Gaussian ensemble to a Gumbel distribution, as well as universality for an arbitrary radially symmetric potential. Secondly, it is shown that this approach can be generalised to obtain convergence of the eigenvalue with smallest modulus and its universality for ring distributions. Most interestingly, the here presented techniques are used to compute all slowly varying finite N correction of the above distributions, which is important for practical applications, given the slow convergence. Another interesting aspect of this work is the fact that we can use standard techniques from Hermitian random matrices to obtain the extreme value statistics of non-Hermitian random matrices resembling the large N expansion used in context of the double scaling limit of Hermitian matrix models in string theory.

The effect of ubiquinone and combined antioxidant therapy on oxidative stress markers in non-proliferative diabetic retinopathy: A phase IIa, randomized, double-blind, and placebo-controlled study.

PubMed

Rodríguez-Carrizalez, Adolfo Daniel; Castellanos-González, José Alberto; Martínez-Romero, Esaú César; Miller-Arrevillaga, Guillermo; Pacheco-Moisés, Fermín Paul; Román-Pintos, Luis Miguel; Miranda-Díaz, Alejandra Guillermina

2016-07-01

Objective To evaluate the effect of ubiquinone (Coenzyme Q10) and combined antioxidant therapy (CAT) on oxidative stress markers in non-proliferative diabetic retinopathy (NPDR) under clinical management. Study design In a randomized, double-blind, phase IIa, placebo-controlled, clinical trial, three study groups were formed and administered medications as follows: Group 1, Coenzyme Q10; Group 2, CAT; and Group 3, placebo. Methods Serum levels of the products of lipid peroxidation (LPO) and nitrites/nitrates, as markers of oxidative/nitrosative stress, were measured. As antioxidants, the total antioxidant capacity (TAC), catalase activity, and glutathione peroxidase (GPx) activity were measured. Results Baseline serum levels of LPO and nitrites/nitrates were significantly elevated in the three groups vs. healthy group (P < 0.0001), while final levels in the Coenzyme Q10 and CAT groups were decreased vs. normal levels (P < 0.0001). The baseline TAC was consumed in the three groups (P < 0.0001), while final results in the Coenzyme Q10 and CAT groups improved (P < 0.0001). Baseline catalase activity was increased in all groups vs. normal values (P < 0.001), while final levels in the Coenzyme Q10 (P < 0.001) and CAT groups (P < 0.0001) were decreased. GPx behaved similarly to catalase and improved in the final results (P < 0.0001). Discussion Adjunctive antioxidant treatment for 6 months was effective and safe for improving the oxidative stress in NPDR.

A non-modal analytical method to predict turbulent properties applied to the Hasegawa-Wakatani model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Friedman, B., E-mail: friedman11@llnl.gov; Lawrence Livermore National Laboratory, Livermore, California 94550; Carter, T. A.

2015-01-15

Linear eigenmode analysis often fails to describe turbulence in model systems that have non-normal linear operators and thus nonorthogonal eigenmodes, which can cause fluctuations to transiently grow faster than expected from eigenmode analysis. When combined with energetically conservative nonlinear mode mixing, transient growth can lead to sustained turbulence even in the absence of eigenmode instability. Since linear operators ultimately provide the turbulent fluctuations with energy, it is useful to define a growth rate that takes into account non-modal effects, allowing for prediction of energy injection, transport levels, and possibly even turbulent onset in the subcritical regime. We define such amore » non-modal growth rate using a relatively simple model of the statistical effect that the nonlinearities have on cross-phases and amplitude ratios of the system state variables. In particular, we model the nonlinearities as delta-function-like, periodic forces that randomize the state variables once every eddy turnover time. Furthermore, we estimate the eddy turnover time to be the inverse of the least stable eigenmode frequency or growth rate, which allows for prediction without nonlinear numerical simulation. We test this procedure on the 2D and 3D Hasegawa-Wakatani model [A. Hasegawa and M. Wakatani, Phys. Rev. Lett. 50, 682 (1983)] and find that the non-modal growth rate is a good predictor of energy injection rates, especially in the strongly non-normal, fully developed turbulence regime.« less

A non-modal analytical method to predict turbulent properties applied to the Hasegawa-Wakatani model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Friedman, B.; Carter, T. A.

2015-01-15

Linear eigenmode analysis often fails to describe turbulence in model systems that have non-normal linear operators and thus nonorthogonal eigenmodes, which can cause fluctuations to transiently grow faster than expected from eigenmode analysis. When combined with energetically conservative nonlinear mode mixing, transient growth can lead to sustained turbulence even in the absence of eigenmode instability. Since linear operators ultimately provide the turbulent fluctuations with energy, it is useful to define a growth rate that takes into account non-modal effects, allowing for prediction of energy injection, transport levels, and possibly even turbulent onset in the subcritical regime. Here, we define suchmore » a non-modal growth rate using a relatively simple model of the statistical effect that the nonlinearities have on cross-phases and amplitude ratios of the system state variables. In particular, we model the nonlinearities as delta-function-like, periodic forces that randomize the state variables once every eddy turnover time. Furthermore, we estimate the eddy turnover time to be the inverse of the least stable eigenmode frequency or growth rate, which allows for prediction without nonlinear numerical simulation. Also, we test this procedure on the 2D and 3D Hasegawa-Wakatani model [A. Hasegawa and M. Wakatani, Phys. Rev. Lett. 50, 682 (1983)] and find that the non-modal growth rate is a good predictor of energy injection rates, especially in the strongly non-normal, fully developed turbulence regime.« less

Rotational diffusion of a molecular cat

NASA Astrophysics Data System (ADS)

Katz-Saporta, Ori; Efrati, Efi

We show that a simple isolated system can perform rotational random walk on account of internal excitations alone. We consider the classical dynamics of a ''molecular cat'': a triatomic molecule connected by three harmonic springs with non-zero rest lengths, suspended in free space. In this system, much like for falling cats, the angular momentum constraint is non-holonomic allowing for rotations with zero overall angular momentum. The geometric nonlinearities arising from the non-zero rest lengths of the springs suffice to break integrability and lead to chaotic dynamics. The coupling of the non-integrability of the system and its non-holonomic nature results in an angular random walk of the molecule. We study the properties and dynamics of this angular motion analytically and numerically. For low energy excitations the system displays normal-mode-like motion, while for high enough excitation energy we observe regular random-walk. In between, at intermediate energies we observe an angular Lévy-walk type motion associated with a fractional diffusion coefficient interpolating between the two regimes.

Interactome Analysis of Microtubule-targeting Agents Reveals Cytotoxicity Bases in Normal Cells.

PubMed

Gutiérrez-Escobar, Andrés Julián; Méndez-Callejas, Gina

2017-12-01

Cancer causes millions of deaths annually and microtubule-targeting agents (MTAs) are the most commonly-used anti-cancer drugs. However, the high toxicity of MTAs on normal cells raises great concern. Due to the non-selectivity of MTA targets, we analyzed the interaction network in a non-cancerous human cell. Subnetworks of fourteen MTAs were reconstructed and the merged network was compared against a randomized network to evaluate the functional richness. We found that 71.4% of the MTA interactome nodes are shared, which affects cellular processes such as apoptosis, cell differentiation, cell cycle control, stress response, and regulation of energy metabolism. Additionally, possible secondary targets were identified as client proteins of interphase microtubules. MTAs affect apoptosis signaling pathways by interacting with client proteins of interphase microtubules, suggesting that their primary targets are non-tumor cells. The paclitaxel and doxorubicin networks share essential topological axes, suggesting synergistic effects. This may explain the exacerbated toxicity observed when paclitaxel and doxorubicin are used in combination for cancer treatment. Copyright © 2017 The Authors. Production and hosting by Elsevier B.V. All rights reserved.

Non-random dispersal in the butterfly Maniola jurtina: implications for metapopulation models.

PubMed Central

Conradt, L; Bodsworth, E J; Roper, T J; Thomas, C D

2000-01-01

The dispersal patterns of animals are important in metapopulation ecology because they affect the dynamics and survival of populations. Theoretical models assume random dispersal but little is known in practice about the dispersal behaviour of individual animals or the strategy by which dispersers locate distant habitat patches. In the present study, we released individual meadow brown butterflies (Maniola jurtina) in a non-habitat and investigated their ability to return to a suitable habitat. The results provided three reasons for supposing that meadow brown butterflies do not seek habitat by means of random flight. First, when released within the range of their normal dispersal distances, the butterflies orientated towards suitable habitat at a higher rate than expected at random. Second, when released at larger distances from their habitat, they used a non-random, systematic, search strategy in which they flew in loops around the release point and returned periodically to it. Third, butterflies returned to a familiar habitat patch rather than a non-familiar one when given a choice. If dispersers actively orientate towards or search systematically for distant habitat, this may be problematic for existing metapopulation models, including models of the evolution of dispersal rates in metapopulations. PMID:11007325

The effect of a six-week osteopathic visceral manipulation in patients with non-specific chronic low back pain and functional constipation: study protocol for a randomized controlled trial.

PubMed

Fernandes, Walkyria Vilas Boas; Blanco, Cleofás Rodríguez; Politti, Fabiano; de Cordoba Lanza, Fernanda; Lucareli, Paulo Roberto Garcia; Corrêa, João Carlos Ferrari

2018-03-02

The aim of the proposed study is to analyze the effect of a six-week osteopathic visceral manipulation (OVM) program on the flexion-relaxation phenomenon in individuals with non-specific chronic low back pain (LBP) and functional constipation. An assessor-blinded, two-arm, randomized, placebo-controlled trial will be conducted. The sample will comprise 76 individuals with non-specific chronic LBP who have functional intestinal constipation, aged 18-65 years. The participants will be randomly allocated to two groups: (1) OVM and (2) sham OVM (SOVM). Evaluations will involve an interview, the Oswestry Disability Index, Fear-Avoidance Beliefs Questionnaire, functional constipation according to Rome III criteria, Biering-Sorensen test to normalize electromyographic (EMG) data, T12-L1 paraspinal level of the EMG signal during the flexion-relaxation phenomenon, 11-point numeric pain rating scale and fingertip-to-floor test. OVM and SOVM will be performed once per week for six weeks. Group 1 will receive OVM for 15 min and Group 2 will receive a sham visceral technique. Evaluations will be performed before and after the first session, after six weeks of treatment, and three months after randomization (follow-up). The findings will be analyzed statistically considering a 5% significance level (p ≤ 0.05). The limitation of the study is that the therapist will not be blinded. This will be the first trial to analyze the clinical response and electromyographic signals during the flexion-relaxation phenomenon after OVM. Brazilian Clinical Trial Registry, RBR-7sx8j3 . Registered on 26 October 2017.

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

PubMed

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

2016-02-01

Two-part random effects models (Olsen and Schafer,(1) Tooze et al.(2)) have been applied to repeated measures of semi-continuous data, characterized by a mixture of a substantial proportion of zero values and a skewed distribution of positive values. In the original formulation of this model, the natural logarithm of the positive values is assumed to follow a normal distribution with a constant variance parameter. In this article, we review and consider three extensions of this model, allowing the positive values to follow (a) a generalized gamma distribution, (b) a log-skew-normal distribution, and (c) a normal distribution after the Box-Cox transformation. We allow for the possibility of heteroscedasticity. Maximum likelihood estimation is shown to be conveniently implemented in SAS Proc NLMIXED. The performance of the methods is compared through applications to daily drinking records in a secondary data analysis from a randomized controlled trial of topiramate for alcohol dependence treatment. We find that all three models provide a significantly better fit than the log-normal model, and there exists strong evidence for heteroscedasticity. We also compare the three models by the likelihood ratio tests for non-nested hypotheses (Vuong(3)). The results suggest that the generalized gamma distribution provides the best fit, though no statistically significant differences are found in pairwise model comparisons. © The Author(s) 2012.

Box–Cox Transformation and Random Regression Models for Fecal egg Count Data

PubMed Central

da Silva, Marcos Vinícius Gualberto Barbosa; Van Tassell, Curtis P.; Sonstegard, Tad S.; Cobuci, Jaime Araujo; Gasbarre, Louis C.

2012-01-01

Accurate genetic evaluation of livestock is based on appropriate modeling of phenotypic measurements. In ruminants, fecal egg count (FEC) is commonly used to measure resistance to nematodes. FEC values are not normally distributed and logarithmic transformations have been used in an effort to achieve normality before analysis. However, the transformed data are often still not normally distributed, especially when data are extremely skewed. A series of repeated FEC measurements may provide information about the population dynamics of a group or individual. A total of 6375 FEC measures were obtained for 410 animals between 1992 and 2003 from the Beltsville Agricultural Research Center Angus herd. Original data were transformed using an extension of the Box–Cox transformation to approach normality and to estimate (co)variance components. We also proposed using random regression models (RRM) for genetic and non-genetic studies of FEC. Phenotypes were analyzed using RRM and restricted maximum likelihood. Within the different orders of Legendre polynomials used, those with more parameters (order 4) adjusted FEC data best. Results indicated that the transformation of FEC data utilizing the Box–Cox transformation family was effective in reducing the skewness and kurtosis, and dramatically increased estimates of heritability, and measurements of FEC obtained in the period between 12 and 26 weeks in a 26-week experimental challenge period are genetically correlated. PMID:22303406

Box-Cox Transformation and Random Regression Models for Fecal egg Count Data.

PubMed

da Silva, Marcos Vinícius Gualberto Barbosa; Van Tassell, Curtis P; Sonstegard, Tad S; Cobuci, Jaime Araujo; Gasbarre, Louis C

2011-01-01

Accurate genetic evaluation of livestock is based on appropriate modeling of phenotypic measurements. In ruminants, fecal egg count (FEC) is commonly used to measure resistance to nematodes. FEC values are not normally distributed and logarithmic transformations have been used in an effort to achieve normality before analysis. However, the transformed data are often still not normally distributed, especially when data are extremely skewed. A series of repeated FEC measurements may provide information about the population dynamics of a group or individual. A total of 6375 FEC measures were obtained for 410 animals between 1992 and 2003 from the Beltsville Agricultural Research Center Angus herd. Original data were transformed using an extension of the Box-Cox transformation to approach normality and to estimate (co)variance components. We also proposed using random regression models (RRM) for genetic and non-genetic studies of FEC. Phenotypes were analyzed using RRM and restricted maximum likelihood. Within the different orders of Legendre polynomials used, those with more parameters (order 4) adjusted FEC data best. Results indicated that the transformation of FEC data utilizing the Box-Cox transformation family was effective in reducing the skewness and kurtosis, and dramatically increased estimates of heritability, and measurements of FEC obtained in the period between 12 and 26 weeks in a 26-week experimental challenge period are genetically correlated.

Sensitive Troponin I and Stress Testing in the Emergency Department for the Early Management of Chest Pain Using 2-Hour Protocol.

PubMed

Dadkhah, Shahriar; Almuwaqqat, Zakaria; Sulaiman, Samian; Husein, Husein; Nguyen, Quang; Ali, Saad; Taskesen, Tuncay

2017-09-01

Despite improvements in identifying high-risk patients with non-ST segment ACS (acute coronary syndrome), low risk patients presenting with atypical chest pain and non-diagnostic Electrocardiogram (ECG) continued to undergo unnecessary admissions and testing. Since 1992, our chest pain protocol included using 4-hour serial biomarkers from ED admission in combination with stress testing to evaluate these patients. Our study aimed at determining whether a new accelerated diagnostic protocol using sensitive cardiac troponin I (cTnI) 2 hours after admission to the ED followed by stress testing is safe and effective in emergency settings, allowing for appropriate triage, earlier discharge and reducing costs. We conducted a single center randomized trial at Presence St. Francis Hospital Chest pain center in Evanston, Illinois enrolling sixty-four consecutive patients with atypical chest pain and non-diagnostic ECG, participants were randomized to accelerated 2 hrs protocol or our pre-existing 4-hrs protocol. Sixty patients completed the protocol and were randomized to either a 2-hour (29 patients) or 4-hour protocol using both I-STAT and PATHFAST cTnI (31 Patients). Troponin I was evaluated at 0 and at 2 hours from ED presentation with and additional draw for patients in the 4-hour rule out-group. Patients with normal serial biomarkers were then evaluated with stress testing and qualified for earlier discharge if the stress test was negative, while those with a positive biomarker at any time were admitted. Thirty-six patients had exercise treadmill stress test and 24 patients had either nuclear or Echo stress test. Fifty-three patients had a normal stress test and were discharged home. One patient in the 4-hour group with normal serial troponins developed ventricular tachycardia/fibrillation during the recovery period of a regular stress test. Six patients had a positive PATHFAST cTnI and a normal I-STAT cTnI at 2-hours. Two out of these six patients evaluated by coronary angiography. One patient had severe tortuous coronaries but no significant obstructive lesion and one had a severe CAD who needed Coronary artery bypass grafting (CABG). Three of the six patients had a normal stress test and one patient decided to leave without further testing. None of the patients with a normal stress test had a major cardiac event or adverse cardiac outcome at six-month follow up. This study demonstrates that the 2 hours accelerated protocol using high sensitivity Troponin assay at 0 and 2 hours with comprehensive clinical evaluation and ECG followed by stress testing might be successful in identifying low-risk patient population who may benefit from early discharge from ED reducing associated costs and length of stay.

Properties of networks with partially structured and partially random connectivity

NASA Astrophysics Data System (ADS)

Ahmadian, Yashar; Fumarola, Francesco; Miller, Kenneth D.

2015-01-01

Networks studied in many disciplines, including neuroscience and mathematical biology, have connectivity that may be stochastic about some underlying mean connectivity represented by a non-normal matrix. Furthermore, the stochasticity may not be independent and identically distributed (iid) across elements of the connectivity matrix. More generally, the problem of understanding the behavior of stochastic matrices with nontrivial mean structure and correlations arises in many settings. We address this by characterizing large random N ×N matrices of the form A =M +L J R , where M ,L , and R are arbitrary deterministic matrices and J is a random matrix of zero-mean iid elements. M can be non-normal, and L and R allow correlations that have separable dependence on row and column indices. We first provide a general formula for the eigenvalue density of A . For A non-normal, the eigenvalues do not suffice to specify the dynamics induced by A , so we also provide general formulas for the transient evolution of the magnitude of activity and frequency power spectrum in an N -dimensional linear dynamical system with a coupling matrix given by A . These quantities can also be thought of as characterizing the stability and the magnitude of the linear response of a nonlinear network to small perturbations about a fixed point. We derive these formulas and work them out analytically for some examples of M ,L , and R motivated by neurobiological models. We also argue that the persistence as N →∞ of a finite number of randomly distributed outlying eigenvalues outside the support of the eigenvalue density of A , as previously observed, arises in regions of the complex plane Ω where there are nonzero singular values of L-1(z 1 -M ) R-1 (for z ∈Ω ) that vanish as N →∞ . When such singular values do not exist and L and R are equal to the identity, there is a correspondence in the normalized Frobenius norm (but not in the operator norm) between the support of the spectrum of A for J of norm σ and the σ pseudospectrum of M .

The effects of biome and spatial scale on the Co-occurrence patterns of a group of Namibian beetles

NASA Astrophysics Data System (ADS)

Pitzalis, Monica; Montalto, Francesca; Amore, Valentina; Luiselli, Luca; Bologna, Marco A.

2017-08-01

Co-occurrence patterns (studied by C-score, number of checkerboard units, number of species combinations, and V-ratio, and by an empirical Bayes approach developed by Gotelli and Ulrich, 2010) are crucial elements in order to understand assembly rules in ecological communities at both local and spatial scales. In order to explore general assembly rules and the effects of biome and spatial scale on such rules, here we studied a group of beetles (Coleoptera, Meloidae), using Namibia as a case of study. Data were gathered from 186 sampling sites, which allowed collection of 74 different species. We analyzed data at the level of (i) all sampled sites, (ii) all sites stratified by biome (Savannah, Succulent Karoo, Nama Karoo, Desert), and (iii) three randomly selected nested areas with three spatial scales each. Three competing algorithms were used for all analyses: (i) Fixed-Equiprobable, (ii) Fixed-Fixed, and (iii) Fixed-Proportional. In most of the null models we created, co-occurrence indicators revealed a non-random structure in meloid beetle assemblages at the global scale and at the scale of biomes, with species aggregation being much more important than species segregation in determining this non-randomness. At the level of biome, the same non-random organization was uncovered in assemblages from Savannah (where the aggregation pattern was particularly strong) and Succulent Karoo, but not in Desert and Nama Karoo. We conclude that species facilitation and similar niche in endemic species pairs may be particularly important as community drivers in our case of study. This pattern is also consistent with the evidence of a higher species diversity (normalized according to biome surface area) in the two former biomes. Historical patterns were perhaps also important for Succulent Karoo assemblages. Spatial scale had a reduced effect on patterning our data. This is consistent with the general homogeneity of environmental conditions over wide areas in Namibia.

Combining Exergame Training with Omega-3 Fatty Acid Supplementation: Protocol for a Randomized Controlled Study Assessing the Effect on Neuronal Structure/Function in the Elderly Brain.

PubMed

Schättin, Alexandra; de Bruin, Eling D

2016-01-01

A common problem in the older population is the risk of falling and related injury, immobility, and reduced survival. Age-related neuronal changes, e.g., decline in gray-and white-matter, affect neuronal, cognitive, and motor functioning. The improvement of these factors might decrease fall events in elderly. Studies showed that administration of video game-based physical exercise, a so-called exergame, or omega-3 fatty acid (FA) may improve motor and/or cognitive functioning through neuronal changes in the brain of older adults. The aim of this study is to assess the effects of a combination of exergame training with omega-3 FA supplementation on the elderly brain. We hypothesize that an intervention using a combination approach differently affects on the neuronal structure and function of the elderly's brain as compared to the sole administration of exergame training. The study is a parallel, double-blinded, randomized controlled trial lasting 26 weeks. Sixty autonomous living, non-smoking, and right-handed healthy older (>65 years) adults who live independently or in a senior residency are included, randomized, and allocated to one of two study groups. The experimental group receives a daily amount of 13.5 ml fish oil (including 2.9 g of omega-3 FA), whereas the control group receives a daily amount of 13.5 ml olive oil for 26 weeks. After 16 weeks, both groups start with an exergame training program three times per week. Measurements are performed on three time-points by treatment blinded investigators: pre-intervention measurements, blood sample after 16 week, and post-intervention measurements. The main outcomes are motor evoked potentials of the right M. tibialis anterior (transcranial magnetic stimulation) and response-related potentials (electroencephalography) during a cognitive test. For secondary outcomes, reaction time during cognitive tests and spatio-temporal parameters during gait performance are measured. Statistics will include effect sizes and a 2 × 2-ANOVA with normally distributed data or the non-parametric equivalent for data not fulfilling normal distribution. The randomized controlled study is the first to investigate the effectiveness of exergame training combined with omega-3 FA in counteracting age- and behavioral-dependent neuronal changes in the brain. This study has been registered in the Swiss National Clinical Trials (SNCTP000001623) and the ISRCTN (ISRCTN12084831) Portals.

Sugars, obesity, and cardiovascular disease: results from recent randomized control trials.

PubMed

Rippe, James M; Angelopoulos, Theodore J

2016-11-01

The relationship between sugar consumption and various health-related sequelas is controversial. Some investigators have argued that excessive sugar consumption is associated with increased risk of obesity, coronary heart disease, diabetes (T2D), metabolic syndrome, non-alcoholic fatty liver disease, and stimulation of reward pathways in the brain potentially causing excessive caloric consumption. These concerns have influenced organizations such as the World Health Organization, the Scientific Advisory Committee on Nutrition in England not to exceed 5 % of total energy and the Dietary Guidelines for Americans Advisory Committee 2015 to recommend upper limits of sugar consumption not to exceed 10 % of calories. Data from many randomized control trials (RCTs) do not support linkages between sugar consumption at normal levels within the human diet and various adverse metabolic and health-related effects. Fructose and glucose are typically consumed together in roughly equal proportions from high-fructose corn syrup (also known as isoglucose in Europe) or sucrose. The purpose of this review is to present data from recent RCTs and findings from recent systematic reviews and meta-analyses related to sugar consumption and its putative health effects. This review evaluates findings from recent randomized controlled trials, systematic reviews and meta-analyses into the relationship of sugar consumption and a range of health-related issues including energy-regulating hormones, obesity, cardiovascular disease, diabetes, and accumulation of liver fat and neurologic responses. Data from these sources do not support linkages between sugar consumption at normal levels within the human diet and various adverse metabolic and health-related effects.

Inference of median difference based on the Box-Cox model in randomized clinical trials.

PubMed

Maruo, K; Isogawa, N; Gosho, M

2015-05-10

In randomized clinical trials, many medical and biological measurements are not normally distributed and are often skewed. The Box-Cox transformation is a powerful procedure for comparing two treatment groups for skewed continuous variables in terms of a statistical test. However, it is difficult to directly estimate and interpret the location difference between the two groups on the original scale of the measurement. We propose a helpful method that infers the difference of the treatment effect on the original scale in a more easily interpretable form. We also provide statistical analysis packages that consistently include an estimate of the treatment effect, covariance adjustments, standard errors, and statistical hypothesis tests. The simulation study that focuses on randomized parallel group clinical trials with two treatment groups indicates that the performance of the proposed method is equivalent to or better than that of the existing non-parametric approaches in terms of the type-I error rate and power. We illustrate our method with cluster of differentiation 4 data in an acquired immune deficiency syndrome clinical trial. Copyright © 2015 John Wiley & Sons, Ltd.

Gravitropic moss cells default to spiral growth on the clinostat and in microgravity during spaceflight

NASA Technical Reports Server (NTRS)

Kern, Volker D.; Schwuchow, Jochen M.; Reed, David W.; Nadeau, Jeanette A.; Lucas, Jessica; Skripnikov, Alexander; Sack, Fred D.

2005-01-01

In addition to shoots and roots, the gravity (g)-vector orients the growth of specialized cells such as the apical cell of dark-grown moss protonemata. Each apical cell of the moss Ceratodon purpureus senses the g-vector and adjusts polar growth accordingly producing entire cultures of upright protonemata (negative gravitropism). The effect of withdrawing a constant gravity stimulus on moss growth was studied on two NASA Space Shuttle (STS) missions as well as during clinostat rotation on earth. Cultures grown in microgravity (spaceflight) on the STS-87 mission exhibited two successive phases of non-random growth and patterning, a radial outgrowth followed by the formation of net clockwise spiral growth. Also, cultures pre-aligned by unilateral light developed clockwise hooks during the subsequent dark period. The second spaceflight experiment flew on STS-107 which disintegrated during its descent on 1 February 2003. However, most of the moss experimental hardware was recovered on the ground, and most cultures, which had been chemically fixed during spaceflight, were retrieved. Almost all intact STS-107 cultures displayed strong spiral growth. Non-random culture growth including clockwise spiral growth was also observed after clinostat rotation. Together these data demonstrate the existence of default non-random growth patterns that develop at a population level in microgravity, a response that must normally be overridden and masked by a constant g-vector on earth.

A randomized, double-blind, controlled trial on non-opioid analgesics and opioid consumption for postoperative pain relief after laparoscopic cholecystectomy.

PubMed

Abdulla, S; Eckhardt, R; Netter, U; Abdulla, W

2012-01-01

Following laparoscopic cholecystectomy, an effective post-operative pain control is necessary, at least during the first 24 hours. We present a randomized, double-blind trial on the effect of the combined use of intravenous parecoxib, and metamizol or paracetamol on piritramide consumption using a patient-controlled analgesia (PCA) pump in patients recovering from laparoscopic cholecystectomy. 120 patients were randomly allocated to four patient groups treated with normal saline or one of non-opioid analgesics (parecoxib 40 mg twice daily, metamizol 1 g three times daily, paracetamol 1 g three times daily) in addition to piritramide using the PCA pump. Beginning in the post-anesthesia care unit (PACU), patients were asked every 2 h for 6 hours and afterwards once every 6 h to quantify their pain experience at rest while piritramide consumption was recorded. In all groups, piritramide consumption was high in PACU. Only metamizol significantly reduced piritramide consumption compared to the others upon discharge from PACU. Overall, cumulative piritramide consumption was slightly lower in the metamizol group and higher in the NaCl group; however, these findings were statistically not significant. VAS scores were highest upon arrival in PACU and dropped almost continuously after surgery. A significantly lower postoperative pain intensity was only found in the parecoxib group at 24 h after surgery compared to the metamizol group. The efficacy of tested additive medications on piritramide consumption and pain relief is weak and there is no clear-cut difference between the non-opioid drugs used.

Detection of cervical lesions by multivariate analysis of diffuse reflectance spectra: a clinical study.

PubMed

Prabitha, Vasumathi Gopala; Suchetha, Sambasivan; Jayanthi, Jayaraj Lalitha; Baiju, Kamalasanan Vijayakumary; Rema, Prabhakaran; Anuraj, Koyippurath; Mathews, Anita; Sebastian, Paul; Subhash, Narayanan

2016-01-01

Diffuse reflectance (DR) spectroscopy is a non-invasive, real-time, and cost-effective tool for early detection of malignant changes in squamous epithelial tissues. The present study aims to evaluate the diagnostic power of diffuse reflectance spectroscopy for non-invasive discrimination of cervical lesions in vivo. A clinical trial was carried out on 48 sites in 34 patients by recording DR spectra using a point-monitoring device with white light illumination. The acquired data were analyzed and classified using multivariate statistical analysis based on principal component analysis (PCA) and linear discriminant analysis (LDA). Diagnostic accuracies were validated using random number generators. The receiver operating characteristic (ROC) curves were plotted for evaluating the discriminating power of the proposed statistical technique. An algorithm was developed and used to classify non-diseased (normal) from diseased sites (abnormal) with a sensitivity of 72 % and specificity of 87 %. While low-grade squamous intraepithelial lesion (LSIL) could be discriminated from normal with a sensitivity of 56 % and specificity of 80 %, and high-grade squamous intraepithelial lesion (HSIL) from normal with a sensitivity of 89 % and specificity of 97 %, LSIL could be discriminated from HSIL with 100 % sensitivity and specificity. The areas under the ROC curves were 0.993 (95 % confidence interval (CI) 0.0 to 1) and 1 (95 % CI 1) for the discrimination of HSIL from normal and HSIL from LSIL, respectively. The results of the study show that DR spectroscopy could be used along with multivariate analytical techniques as a non-invasive technique to monitor cervical disease status in real time.

Randomized controlled GH trial: effects on anthropometry, body composition and body proportions in a large group of children with Prader-Willi syndrome.

PubMed

Festen, Dederieke A M; de Lind van Wijngaarden, Roderick; van Eekelen, Marielle; Otten, Barto J; Wit, Jan M; Duivenvoorden, Hugo J; Hokken-Koelega, Anita C S

2008-09-01

Prader-Willi syndrome (PWS) children have impaired growth, and abnormal body composition. Previous 1-year controlled studies showed improvement of height and body composition during GH-treatment. To evaluate growth, body composition and body proportions during GH-treatment in a large group of PWS children. We performed a randomized controlled GH trial in 91 prepubertal PWS children (42 infants, 49 children, aged 3-14 years). After stratification for age, infants were randomized to GH-treatment (GH-group; 1 mg/m(2)/day; n = 20), or no treatment (control group; n = 22) for 1 year. In the second year all infants were treated with GH. After stratification for BMI, children > 3 years of age were randomized to GH-treatment (GH-group; 1 mg/m(2)/day; n = 27) or no treatment (control group; n = 22) for 2 years. Anthropometric parameters were assessed once in every 3 months. Body composition was measured by Dual Energy X-ray Absorptiometry. Median (interquartile range, iqr) height SDS increased during 2 years of GH in infants from -2.3 (-2.8 to -0.7) to -0.4 (-1.1-0.0) and in prepubertal children from -2.0 (-3.1 to -1.7) to -0.6 (-1.1 to -0.1). In non-GH-treated children height SDS did not increase. Head circumference completely normalized during 1 and 2 years of GH in infants and children, respectively. Body fat percentage and body proportions improved in GH-treated children, but did not completely normalize. Lean body mass SDS improved compared to the control group. Serum IGF-I increased to levels above the normal range in most GH-treated children. Our randomized study shows that GH-treatment in PWS children significantly improves height, BMI, head circumference, body composition and body proportions. PWS children are highly sensitive to GH, suggesting that monitoring of serum IGF-I is indicated.

Comprehensive non-dimensional normalization of gait data.

PubMed

Pinzone, Ornella; Schwartz, Michael H; Baker, Richard

2016-02-01

Normalizing clinical gait analysis data is required to remove variability due to physical characteristics such as leg length and weight. This is particularly important for children where both are associated with age. In most clinical centres conventional normalization (by mass only) is used whereas there is a stronger biomechanical argument for non-dimensional normalization. This study used data from 82 typically developing children to compare how the two schemes performed over a wide range of temporal-spatial and kinetic parameters by calculating the coefficients of determination with leg length, weight and height. 81% of the conventionally normalized parameters had a coefficient of determination above the threshold for a statistical association (p<0.05) compared to 23% of those normalized non-dimensionally. All the conventionally normalized parameters exceeding this threshold showed a reduced association with non-dimensional normalization. In conclusion, non-dimensional normalization is more effective that conventional normalization in reducing the effects of height, weight and age in a comprehensive range of temporal-spatial and kinetic parameters. Copyright © 2015 Elsevier B.V. All rights reserved.

Application of Poisson random effect models for highway network screening.

PubMed

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.

Mipomersen is a promising therapy in the management of hypercholesterolemia: a meta-analysis of randomized controlled trials.

PubMed

Li, Na; Li, Qing; Tian, Xia-Qiu; Qian, Hai-Yan; Yang, Yue-Jin

2014-10-01

By inhibiting apolipoprotein B (ApoB) synthesis, mipomersen can significantly reduce ApoB-containing lipoproteins in hypercholesterolemic patients. This study sought to ascertain both the extent to which mipomersen can decrease ApoB-containing lipoproteins and the safety of mipomersen therapy. Studies were identified through PubMed, CENTRAL, Embase, Clinical Trials, reviews, and reference lists of relevant papers. The efficacy endpoints were the changes in low-density lipoprotein cholesterol (LDL-C), non-high-density lipoprotein cholesterol (non-HDL-C), ApoB, and lipoprotein (a) [Lp(a)]. The safety endpoints were the incidence of injection-site reactions, flu-like symptoms, and elevated transaminases. Six randomized controlled trials with 444 patients were included in the analysis. Compared with the placebo group, patients who received mipomersen therapy had a significant reduction in LDL-C (33.13%), as well as a reduction in non-HDL-C (31.70%), ApoB (33.27%), and LP(a) (26.34%). Mipomersen therapy was also associated with an obvious increase in injection-site reactions with an odds ratio (OR) of 14.15, flu-like symptoms with an OR of 2.07, and alanine aminotransferase levels ≥ 3 × the upper limit of normal with an OR of 11.21. Mipomersen therapy is effective for lowering ApoB-containing lipoproteins in patients with severe hypercholesterolemia. Future studies exploring how to minimize side effects of mipomersen therapy are needed.

Meta-analysis of two studies in the presence of heterogeneity with applications in rare diseases.

PubMed

Friede, Tim; Röver, Christian; Wandel, Simon; Neuenschwander, Beat

2017-07-01

Random-effects meta-analyses are used to combine evidence of treatment effects from multiple studies. Since treatment effects may vary across trials due to differences in study characteristics, heterogeneity in treatment effects between studies must be accounted for to achieve valid inference. The standard model for random-effects meta-analysis assumes approximately normal effect estimates and a normal random-effects model. However, standard methods based on this model ignore the uncertainty in estimating the between-trial heterogeneity. In the special setting of only two studies and in the presence of heterogeneity, we investigate here alternatives such as the Hartung-Knapp-Sidik-Jonkman method (HKSJ), the modified Knapp-Hartung method (mKH, a variation of the HKSJ method) and Bayesian random-effects meta-analyses with priors covering plausible heterogeneity values; R code to reproduce the examples is presented in an appendix. The properties of these methods are assessed by applying them to five examples from various rare diseases and by a simulation study. Whereas the standard method based on normal quantiles has poor coverage, the HKSJ and mKH generally lead to very long, and therefore inconclusive, confidence intervals. The Bayesian intervals on the whole show satisfying properties and offer a reasonable compromise between these two extremes. © 2016 The Authors. Biometrical Journal published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Efficacy of a church-based lifestyle intervention programme to control high normal blood pressure and/or high normal blood glucose in church members: a randomized controlled trial in Pretoria, South Africa.

PubMed

Pengpid, Supa; Peltzer, Karl; Skaal, Linda

2014-06-06

In persons 15 years and above in South Africa the prevalence of pre-diabetes and diabetes has been estimated at 9.1% and 9.6%, respectively, and the prevalence of systolic prehypertension and hypertension, 38.2% and 24.6%, respectively. Elevated blood glucose and elevated blood pressure are prototype of preventable chronic cardiovascular disease risk factors.Lifestyle interventions have been shown to control high normal blood pressure and/or high normal blood glucose. This study proposes to evaluate the efficacy of a community (church)-based lifestyle intervention programme to control high normal blood pressure and/or high normal blood glucose in church members in a randomized controlled trial in Gauteng, South Africa. The objectives are to: (1) measure non-communicable diseases profile, including hypertension and diabetes, health behaviours, weight management and psychological distress of church members; (2) measure the reduction of blood glucose and blood pressure levels after the intervention; (3) prevent the development of impaired glucose tolerance; (4) compare health behaviours, weight management and psychological distress, blood glucose and blood pressure levels between intervention and control groups, and within group during 6, 12, 24 and 36 months during and post intervention. The study will use a group-randomized design, recruiting 300 church members from 12 churches. Churches will be randomly assigned to experimental and control conditions. Lifestyle interventions may prevent from the development of high blood pressure and/or diabetes. The findings will impact public health and will enable the health ministry to formulate policy related to lifestyle interventions to control blood pressure and glucose. PACTR201105000297151.

Estimating Latent Variable Interactions With Non-Normal Observed Data: A Comparison of Four Approaches

PubMed Central

Cham, Heining; West, Stephen G.; Ma, Yue; Aiken, Leona S.

2012-01-01

A Monte Carlo simulation was conducted to investigate the robustness of four latent variable interaction modeling approaches (Constrained Product Indicator [CPI], Generalized Appended Product Indicator [GAPI], Unconstrained Product Indicator [UPI], and Latent Moderated Structural Equations [LMS]) under high degrees of non-normality of the observed exogenous variables. Results showed that the CPI and LMS approaches yielded biased estimates of the interaction effect when the exogenous variables were highly non-normal. When the violation of non-normality was not severe (normal; symmetric with excess kurtosis < 1), the LMS approach yielded the most efficient estimates of the latent interaction effect with the highest statistical power. In highly non-normal conditions, the GAPI and UPI approaches with ML estimation yielded unbiased latent interaction effect estimates, with acceptable actual Type-I error rates for both the Wald and likelihood ratio tests of interaction effect at N ≥ 500. An empirical example illustrated the use of the four approaches in testing a latent variable interaction between academic self-efficacy and positive family role models in the prediction of academic performance. PMID:23457417

An elaborate data set on human gait and the effect of mechanical perturbations

PubMed Central

Hnat, Sandra K.; van den Bogert, Antonie J.

2015-01-01

Here we share a rich gait data set collected from fifteen subjects walking at three speeds on an instrumented treadmill. Each trial consists of 120 s of normal walking and 480 s of walking while being longitudinally perturbed during each stance phase with pseudo-random fluctuations in the speed of the treadmill belt. A total of approximately 1.5 h of normal walking (>5000 gait cycles) and 6 h of perturbed walking (>20,000 gait cycles) is included in the data set. We provide full body marker trajectories and ground reaction loads in addition to a presentation of processed data that includes gait events, 2D joint angles, angular rates, and joint torques along with the open source software used for the computations. The protocol is described in detail and supported with additional elaborate meta data for each trial. This data can likely be useful for validating or generating mathematical models that are capable of simulating normal periodic gait and non-periodic, perturbed gaits. PMID:25945311

Risk analytics for hedge funds

NASA Astrophysics Data System (ADS)

Pareek, Ankur

2005-05-01

The rapid growth of the hedge fund industry presents significant business opportunity for the institutional investors particularly in the form of portfolio diversification. To facilitate this, there is a need to develop a new set of risk analytics for investments consisting of hedge funds, with the ultimate aim to create transparency in risk measurement without compromising the proprietary investment strategies of hedge funds. As well documented in the literature, use of dynamic options like strategies by most of the hedge funds make their returns highly non-normal with fat tails and high kurtosis, thus rendering Value at Risk (VaR) and other mean-variance analysis methods unsuitable for hedge fund risk quantification. This paper looks at some unique concerns for hedge fund risk management and will particularly concentrate on two approaches from physical world to model the non-linearities and dynamic correlations in hedge fund portfolio returns: Self Organizing Criticality (SOC) and Random Matrix Theory (RMT).Random Matrix Theory analyzes correlation matrix between different hedge fund styles and filters random noise from genuine correlations arising from interactions within the system. As seen in the results of portfolio risk analysis, it leads to a better portfolio risk forecastability and thus to optimum allocation of resources to different hedge fund styles. The results also prove the efficacy of self-organized criticality and implied portfolio correlation as a tool for risk management and style selection for portfolios of hedge funds, being particularly effective during non-linear market crashes.

Effect of high-protein or normal-protein diet on weight loss, body composition, hormone, and metabolic profile in southern Brazilian women with polycystic ovary syndrome: a randomized study.

PubMed

Toscani, Mariana K; Mario, Fernanda M; Radavelli-Bagatini, Simone; Wiltgen, Denusa; Matos, Maria Cristina; Spritzer, Poli Maria

2011-11-01

The aim of the present study was to assess the effects of a high protein (HP) and a normal protein (NP) diet on patients with polycystic ovary syndrome (PCOS) and body mass index-matched controls in a sample of southern Brazilian women. This 8-week randomized trial was carried out at a university gynecological endocrinology clinic and included 18 patients with PCOS and 22 controls. Changes in weight, body composition, hormone, and metabolic profile were analyzed in women randomized to receive HP (30% protein, 40% carbohydrate, and 30% lipid) or NP (15% protein, 55% carbohydrate, and 30% lipid). The energy content was estimated for each participant at 20-25 kcal/kg current weight/day. Physical activity, blood pressure, homeostasis model assessment (HOMA) index, and fasting and 2-h glucose and insulin remained stable during the intervention in PCOS and controls, even in the presence of weight loss. There were no changes in lipid profile in either group. In contrast, body weight, body mass index (BMI), waist circumference, percent of body fat, and sum of trunk skinfolds decreased significantly after both diets in both groups. Total testosterone also decreased in PCOS and controls regardless of diet. In conclusion, calorie reduction, rather than protein content, seemed to affect body composition and hormonal profile in this short-term study. These findings emphasize the role of non-pharmacological interventions to reduce weight and ameliorate the anthropometric and clinical phenotype in PCOS.

Clinical use of proton-pump inhibitors but not H2-blockers or antacid/alginates raises the serum levels of amidated gastrin-17, pepsinogen I and pepsinogen II in a random adult population.

PubMed

Agréus, Lars; Storskrubb, Tom; Aro, Pertti; Ronkainen, Jukka; Talley, Nicholas J; Sipponen, Pentti

2009-01-01

Proton-pump inhibitors (PPIs), H(2) receptor antagonists (H(2)RAs) and antacids/alginates reduce intragastric acidity and may thus influence normal gastric physiology. The purpose of this study was to examine the effect of these compounds on serum levels of amidated gastrin-17 (G-17) and pepsinogens (PGI & PGII) in a large, random, adult Swedish population sample with uninfected stomach mucosa. The initial sample subjects (n=1000, mean age 50 years, range 20-80 years) completed a questionnaire on the use of acid inhibitory drugs 1 week and/or 3 months before study entry. All subjects (n=590) with normal gastric mucosa as delineated by serum biomarkers were included. Among them, serum levels of PGI, PGII and G-17 were compared between those who used acid inhibitory drugs and those who did not. The serum levels of G-17 or pepsinogens in the subjects who reported use of H(2)RAs (n=18) or antacid/alginates (n=66) during the previous 3 months did not differ from those in non-users (n=471). However, the median levels of G-17 and pepsinogens were significantly (p<0.001) higher among the PPI users (n=35) than among non-users: the levels were approximately doubled. The ratio of PGI/PGII was, however, similar between PPI users and non-users, or those using antacids/alginates or H(2)RAs. Among subjects using PPIs, the serum levels of pepsinogens correlated positively (p<0.01) with the serum levels of G-17. PPIs but not antacids/alginates or H(2)RAs markedly increase the fasting levels of serum amidated G-17 and pepsinogens among ordinary patients in everyday clinical practice.

IS THE SUICIDE RATE A RANDOM WALK?

PubMed

Yang, Bijou; Lester, David; Lyke, Jennifer; Olsen, Robert

2015-06-01

The yearly suicide rates for the period 1933-2010 and the daily suicide numbers for 1990 and 1991 were examined for whether the distribution of difference scores (from year to year and from day to day) fitted a normal distribution, a characteristic of stochastic processes that follow a random walk. If the suicide rate were a random walk, then any disturbance to the suicide rate would have a permanent effect and national suicide prevention efforts would likely fail. The distribution of difference scores from day to day (but not the difference scores from year to year) fitted a normal distribution and, therefore, were consistent with a random walk.

Short-term effects of sports taping on navicular height, navicular drop and peak plantar pressure in healthy elite athletes: A within-subject comparison.

PubMed

Kim, Taegyu; Park, Jong-Chul

2017-11-01

Medial tibial stress syndrome (MTSS) is one of the most common exercise-induced leg pain. The navicular drop (ND) was identified as a risk factor for MTSS. This study aimed to evaluate the short-term effects of sports taping applied to the supporting lower leg during sitting, standing, walking, and jogging to restrict the ND in healthy elite athletes.Twenty-four healthy elite athletes without a history of exercise-induced pain or injuries in the lower limbs participated in this study (median age: 21.00 years; 1st--3rd quartiles; 19.25-22.00). The 4 taping conditions were used: rigid taping (RT), kinesiology taping (KT), placebo taping (PT), and non-taping (NT). The order of taping techniques was randomly assigned. Normalized navicular height (NH), ND, and normalized ND evaluated using 3-dimensional motion analysis, and normalized peak plantar pressure (PP) were compared in 4 taping conditions during sitting, standing, walking, and jogging.During sitting, the normalized NH of RT is higher than that of NT, KT, and PT (χ = 17.30, P = .001), while during jogging, the normalized NH of RT is higher than that of NT and PT (χ = 10.55, P = .014). The normalized peak PP of NT is higher than that of PT (χ = 8.871, P = .031) in the lateral midfoot region.This study showed the RT technique maintained NH during sitting and jogging, and the RT technique could be an effective preventive and treatment strategy for MTSS.

Structural Dynamics of Management Zones for the Site-Specific Control of Tarnished Plant Bugs in Cotton

USDA-ARS?s Scientific Manuscript database

Precision-based agricultural application of insecticide relies on a non-random distribution of pests; tarnished plant bugs (Lygus lineolaris) are known to prefer vigorously growing patches of cotton. Management zones for various crops have been readily defined using NDVI (Normalized Difference Vege...

Normalized sensitivities and parameter identifiability of in situ diffusion experiments on Callovo Oxfordian clay at Bure site

NASA Astrophysics Data System (ADS)

Samper, J.; Dewonck, S.; Zheng, L.; Yang, Q.; Naves, A.

Diffusion of inert and reactive tracers (DIR) is an experimental program performed by ANDRA at Bure underground research laboratory in Meuse/Haute Marne (France) to characterize diffusion and retention of radionuclides in Callovo-Oxfordian (C-Ox) argillite. In situ diffusion experiments were performed in vertical boreholes to determine diffusion and retention parameters of selected radionuclides. C-Ox clay exhibits a mild diffusion anisotropy due to stratification. Interpretation of in situ diffusion experiments is complicated by several non-ideal effects caused by the presence of a sintered filter, a gap between the filter and borehole wall and an excavation disturbed zone (EdZ). The relevance of such non-ideal effects and their impact on estimated clay parameters have been evaluated with numerical sensitivity analyses and synthetic experiments having similar parameters and geometric characteristics as real DIR experiments. Normalized dimensionless sensitivities of tracer concentrations at the test interval have been computed numerically. Tracer concentrations are found to be sensitive to all key parameters. Sensitivities are tracer dependent and vary with time. These sensitivities are useful to identify which are the parameters that can be estimated with less uncertainty and find the times at which tracer concentrations begin to be sensitive to each parameter. Synthetic experiments generated with prescribed known parameters have been interpreted automatically with INVERSE-CORE 2D and used to evaluate the relevance of non-ideal effects and ascertain parameter identifiability in the presence of random measurement errors. Identifiability analysis of synthetic experiments reveals that data noise makes difficult the estimation of clay parameters. Parameters of clay and EdZ cannot be estimated simultaneously from noisy data. Models without an EdZ fail to reproduce synthetic data. Proper interpretation of in situ diffusion experiments requires accounting for filter, gap and EdZ. Estimates of the effective diffusion coefficient and the porosity of clay are highly correlated, indicating that these parameters cannot be estimated simultaneously. Accurate estimation of De and porosities of clay and EdZ is only possible when the standard deviation of random noise is less than 0.01. Small errors in the volume of the circulation system do not affect clay parameter estimates. Normalized sensitivities as well as the identifiability analysis of synthetic experiments provide additional insight on inverse estimation of in situ diffusion experiments and will be of great benefit for the interpretation of real DIR in situ diffusion experiments.

Using empirical Bayes predictors from generalized linear mixed models to test and visualize associations among longitudinal outcomes.

PubMed

Mikulich-Gilbertson, Susan K; Wagner, Brandie D; Grunwald, Gary K; Riggs, Paula D; Zerbe, Gary O

2018-01-01

Medical research is often designed to investigate changes in a collection of response variables that are measured repeatedly on the same subjects. The multivariate generalized linear mixed model (MGLMM) can be used to evaluate random coefficient associations (e.g. simple correlations, partial regression coefficients) among outcomes that may be non-normal and differently distributed by specifying a multivariate normal distribution for their random effects and then evaluating the latent relationship between them. Empirical Bayes predictors are readily available for each subject from any mixed model and are observable and hence, plotable. Here, we evaluate whether second-stage association analyses of empirical Bayes predictors from a MGLMM, provide a good approximation and visual representation of these latent association analyses using medical examples and simulations. Additionally, we compare these results with association analyses of empirical Bayes predictors generated from separate mixed models for each outcome, a procedure that could circumvent computational problems that arise when the dimension of the joint covariance matrix of random effects is large and prohibits estimation of latent associations. As has been shown in other analytic contexts, the p-values for all second-stage coefficients that were determined by naively assuming normality of empirical Bayes predictors provide a good approximation to p-values determined via permutation analysis. Analyzing outcomes that are interrelated with separate models in the first stage and then associating the resulting empirical Bayes predictors in a second stage results in different mean and covariance parameter estimates from the maximum likelihood estimates generated by a MGLMM. The potential for erroneous inference from using results from these separate models increases as the magnitude of the association among the outcomes increases. Thus if computable, scatterplots of the conditionally independent empirical Bayes predictors from a MGLMM are always preferable to scatterplots of empirical Bayes predictors generated by separate models, unless the true association between outcomes is zero.

Short-term and practice effects of metronome pacing in Parkinson's disease patients with gait freezing while in the 'on' state: randomized single blind evaluation.

PubMed

Cubo, Esther; Leurgans, Sue; Goetz, Christopher G

2004-12-01

In a randomized single blind parallel study, we tested the efficacy of an auditory metronome on walking speed and freezing in Parkinson's disease (PD) patients with freezing gait impairment during their 'on' function. No pharmacological treatment is effective in managing 'on' freezing in PD. Like visual cues that can help overcome freezing, rhythmic auditory pacing may provide cues that help normalize walking pace and overcome freezing. Non-demented PD patients with freezing during their 'on' state walked under two conditions, in randomized order: unassisted walking and walking with the use of an audiocassette with a metronome recording. The walking trials were randomized and gait variables were rated from videotapes by a blinded evaluator. Outcome measures were total walking time (total trial time-total freezing time), which was considered the time over a course of specified length, freezing time, average freeze duration and number of freezes. All outcomes were averaged across trials for each person and then compared across conditions using Signed Rank tests. Twelve non-demented PD patients with a mean age of 65.8 +/- 11.2 years, and mean PD duration of 12.4 +/- 7.3 years were included. The use of the metronome slowed ambulation and increased the total walking time (P < 0.0005) only during the first visit, without affecting any freezing variable. In the nine patients who took the metronome recording home and used it daily for 1 week while walking, freezing remained unimproved. Though advocated in prior publications as a walking aid for PD patients, auditory metronome pacing slows walking and is not a beneficial intervention for freezing during their 'on' periods.

A randomized controlled trial of brain training with non-action video games in older adults: results of the 3-month follow-up

PubMed Central

Ballesteros, Soledad; Mayas, Julia; Prieto, Antonio; Toril, Pilar; Pita, Carmen; Laura, Ponce de León; Reales, José M.; Waterworth, John A.

2015-01-01

This randomized controlled study (ClinicalTrials.gov NCT02007616) investigated the maintenance of training effects of 20 1-hr non-action video game training sessions with selected games from a commercial package on several age-declining cognitive functions and subjective wellbeing after a 3-month no-contact period. Two groups of cognitively normal older adults participated in both the post-training (posttest) and the present follow-up study, the experimental group who received training and the control group who attended several meetings with the research team during the study but did not receive training. Groups were similar at baseline on demographics, vocabulary, global cognition, and depression status. Significant improvements in the trained group, and no variation in the control group had been previously found at posttest, in processing speed, attention and visual recognition memory, as well as in two dimensions of subjective wellbeing. In the current study, improvement from baseline to 3 months follow-up was found only in wellbeing (Affection and Assertivity dimensions) in the trained group whereas there was no change in the control group. Previous significant improvements in processing speed, attention and spatial memory become non-significant after the 3-month interval. Training older adults with non-action video games enhanced aspects of cognition just after training but this effect disappeared after a 3-month no-contact follow-up period. Cognitive plasticity can be induced in older adults by training, but to maintain the benefits periodic boosting sessions would be necessary. PMID:25926790

A randomized controlled trial of brain training with non-action video games in older adults: results of the 3-month follow-up.

PubMed

Ballesteros, Soledad; Mayas, Julia; Prieto, Antonio; Toril, Pilar; Pita, Carmen; Laura, Ponce de León; Reales, José M; Waterworth, John A

2015-01-01

This randomized controlled study (ClinicalTrials.gov NCT02007616) investigated the maintenance of training effects of 20 1-hr non-action video game training sessions with selected games from a commercial package on several age-declining cognitive functions and subjective wellbeing after a 3-month no-contact period. Two groups of cognitively normal older adults participated in both the post-training (posttest) and the present follow-up study, the experimental group who received training and the control group who attended several meetings with the research team during the study but did not receive training. Groups were similar at baseline on demographics, vocabulary, global cognition, and depression status. Significant improvements in the trained group, and no variation in the control group had been previously found at posttest, in processing speed, attention and visual recognition memory, as well as in two dimensions of subjective wellbeing. In the current study, improvement from baseline to 3 months follow-up was found only in wellbeing (Affection and Assertivity dimensions) in the trained group whereas there was no change in the control group. Previous significant improvements in processing speed, attention and spatial memory become non-significant after the 3-month interval. Training older adults with non-action video games enhanced aspects of cognition just after training but this effect disappeared after a 3-month no-contact follow-up period. Cognitive plasticity can be induced in older adults by training, but to maintain the benefits periodic boosting sessions would be necessary.

The effect of science learning integrated with local potential to improve science process skills

NASA Astrophysics Data System (ADS)

Rahardini, Riris Riezqia Budy; Suryadarma, I. Gusti Putu; Wilujeng, Insih

2017-08-01

This research was aimed to know the effectiveness of science learning that integrated with local potential to improve student`s science process skill. The research was quasi experiment using non-equivalent control group design. The research involved all student of Muhammadiyah Imogiri Junior High School on grade VII as a population. The sample in this research was selected through cluster random sampling, namely VII B (experiment group) and VII C (control group). Instrument that used in this research is a nontest instrument (science process skill observation's form) adapted Desak Megawati's research (2016). The aspect of science process skills were making observation and communication. The data were using univariat (ANOVA) analyzed at 0,05 significance level and normalized gain score for science process skill increase's category. The result is science learning that integrated with local potential was effective to improve science process skills of student (Sig. 0,00). This learning can increase science process skill, shown by a normalized gain score value at 0,63 (medium category) in experiment group and 0,29 (low category) in control group.

Peer influence on pre-adolescent girls' snack intake: effects of weight status.

PubMed

Salvy, Sarah-Jeanne; Romero, Natalie; Paluch, Rocco; Epstein, Leonard H

2007-07-01

Although most eating occurs in a social context, the effects of peer influence on child eating have not been the object of systematic experimental study. The present study assesses the effects of peer influence on lean and overweight pre-adolescent girls' snack intake as a function of the co-eaters' weight status. The weight status of the participants was varied by studying weight discordant dyads (i.e., one lean and one overweight participant) and weight concordant dyads (i.e., both members of the dyads were either lean or overweight). Results from the random regression model indicate that overweight girls eating with an overweight peer consumed more kilocalories than overweight participants eating with a normal-weight peer. Normal-weight participants eating with overweight peers ate similar amounts as those eating with lean eating companions. The regression model improved when the partners' food intake was entered in the model, indicating that the peers' intake was a significant predictor of participants' snack consumption. This study underscores differences in responses to the social environment between overweight and non-overweight youths.

The Effect of the Multivariate Box-Cox Transformation on the Power of MANOVA.

ERIC Educational Resources Information Center

Kirisci, Levent; Hsu, Tse-Chi

Most of the multivariate statistical techniques rely on the assumption of multivariate normality. The effects of non-normality on multivariate tests are assumed to be negligible when variance-covariance matrices and sample sizes are equal. Therefore, in practice, investigators do not usually attempt to remove non-normality. In this simulation…

Non-linear continuous time random walk models★

NASA Astrophysics Data System (ADS)

Stage, Helena; Fedotov, Sergei

2017-11-01

A standard assumption of continuous time random walk (CTRW) processes is that there are no interactions between the random walkers, such that we obtain the celebrated linear fractional equation either for the probability density function of the walker at a certain position and time, or the mean number of walkers. The question arises how one can extend this equation to the non-linear case, where the random walkers interact. The aim of this work is to take into account this interaction under a mean-field approximation where the statistical properties of the random walker depend on the mean number of walkers. The implementation of these non-linear effects within the CTRW integral equations or fractional equations poses difficulties, leading to the alternative methodology we present in this work. We are concerned with non-linear effects which may either inhibit anomalous effects or induce them where they otherwise would not arise. Inhibition of these effects corresponds to a decrease in the waiting times of the random walkers, be this due to overcrowding, competition between walkers or an inherent carrying capacity of the system. Conversely, induced anomalous effects present longer waiting times and are consistent with symbiotic, collaborative or social walkers, or indirect pinpointing of favourable regions by their attractiveness. Contribution to the Topical Issue "Continuous Time Random Walk Still Trendy: Fifty-year History, Current State and Outlook", edited by Ryszard Kutner and Jaume Masoliver.

Normal and tumoral melanocytes exhibit q-Gaussian random search patterns.

PubMed

da Silva, Priscila C A; Rosembach, Tiago V; Santos, Anésia A; Rocha, Márcio S; Martins, Marcelo L

2014-01-01

In multicellular organisms, cell motility is central in all morphogenetic processes, tissue maintenance, wound healing and immune surveillance. Hence, failures in its regulation potentiates numerous diseases. Here, cell migration assays on plastic 2D surfaces were performed using normal (Melan A) and tumoral (B16F10) murine melanocytes in random motility conditions. The trajectories of the centroids of the cell perimeters were tracked through time-lapse microscopy. The statistics of these trajectories was analyzed by building velocity and turn angle distributions, as well as velocity autocorrelations and the scaling of mean-squared displacements. We find that these cells exhibit a crossover from a normal to a super-diffusive motion without angular persistence at long time scales. Moreover, these melanocytes move with non-Gaussian velocity distributions. This major finding indicates that amongst those animal cells supposedly migrating through Lévy walks, some of them can instead perform q-Gaussian walks. Furthermore, our results reveal that B16F10 cells infected by mycoplasmas exhibit essentially the same diffusivity than their healthy counterparts. Finally, a q-Gaussian random walk model was proposed to account for these melanocytic migratory traits. Simulations based on this model correctly describe the crossover to super-diffusivity in the cell migration tracks.

Application of machine learning methods to describe the effects of conjugated equine estrogens therapy on region-specific brain volumes

PubMed Central

Casanova, Ramon; Espeland, Mark A.; Goveas, Joseph S.; Davatzikos, Christos; Gaussoin, Sarah A.; Maldjian, Joseph A.; Brunner, Robert L.; Kuller, Lewis H.; Johnson, Karen C.; Mysiw, W. Jerry; Wagner, Benjamin; Resnick, Susan M.

2011-01-01

Use of conjugated equine estrogens (CEE) has been linked to smaller regional brain volumes in women aged ≥65 years, however it is unknown whether this results in a broad-based characteristic pattern of effects. Structural MRI was used to assess regional volumes of normal tissue and ischemic lesions among 513 women who had been enrolled in a randomized clinical trial of CEE therapy for an average of 6.6 years, beginning at ages 65-80 years. A multivariate pattern analysis, based on a machine learning technique that combined Random Forest and logistic regression with L1 penalty, was applied to identify patterns among regional volumes associated with therapy and whether patterns discriminate between treatment groups. The multivariate pattern analysis detected smaller regional volumes of normal tissue within the limbic and temporal lobes among women that had been assigned to CEE therapy. Mean decrements ranged as high as 7% in the left entorhinal cortex and 5% in the left perirhinal cortex, which exceeded the effect sizes reported previously in frontal lobe and hippocampus. Overall accuracy of classification based on these patterns, however, was projected to be only 54.5%. Prescription of CEE therapy for an average of 6.6 years is associated with lower regional brain volumes, but it does not induce a characteristic spatial pattern of changes in brain volumes of sufficient magnitude to discriminate users and non-users. PMID:21292420

Superstatistical generalised Langevin equation: non-Gaussian viscoelastic anomalous diffusion

NASA Astrophysics Data System (ADS)

Ślęzak, Jakub; Metzler, Ralf; Magdziarz, Marcin

2018-02-01

Recent advances in single particle tracking and supercomputing techniques demonstrate the emergence of normal or anomalous, viscoelastic diffusion in conjunction with non-Gaussian distributions in soft, biological, and active matter systems. We here formulate a stochastic model based on a generalised Langevin equation in which non-Gaussian shapes of the probability density function and normal or anomalous diffusion have a common origin, namely a random parametrisation of the stochastic force. We perform a detailed analysis demonstrating how various types of parameter distributions for the memory kernel result in exponential, power law, or power-log law tails of the memory functions. The studied system is also shown to exhibit a further unusual property: the velocity has a Gaussian one point probability density but non-Gaussian joint distributions. This behaviour is reflected in the relaxation from a Gaussian to a non-Gaussian distribution observed for the position variable. We show that our theoretical results are in excellent agreement with stochastic simulations.

The Effect of Early Intervention and Rehabilitation in the Expression of Aquaporin-4; and Ultrastructure Changes on Rat's Offspring's Damaged Brain Caused by Intrauterine Infection

PubMed Central

Rajesh, Kumar; Xiangying, Kong

2015-01-01

Objective To study the effect of early intervention and rehabilitation in the expression of aquaporin-4 and ultrastructure changes on cerebral palsy pups model induced by intrauterine infection. Methods 20 pregnant Wistar rats were consecutively injected with lipopolysaccharide intraperitoneally. 60 Pups born from lipopolysaccharide group were randomly divided into intervention group (n=30) and non-intervention group (n=30); intervention group further divided into early intervention and rehabilitation group (n=10), acupuncture group (n=10) and consolidate group (n=10). Another 5 pregnant rats were injected with normal saline intraperitoneally; 30 pups born from the normal saline group were taken as control group. The intervention group received early intervention, rehabilitation and acupuncture treatment. The motor functions of all pups were assessed via suspension test and modified BBB locomotor score. Aquaporin-4 expression in brain tissue was studied through immunohistochemical and western-blot analysis. Ultrastructure changes in damaged brain and control group were studied electron-microscopically. Results The scores of suspension test and modified BBB locomotor test were significantly higher in the control group than the intervention and non intervention group (p<0.01); higher in the intervention group than the non-intervention group (p<0.01). The expression of Aquaporin-4 was lower in intervention and non intervention group than in the control group (p<0.01); also lower in non-intervention group than the intervention group (p<0.01). Marked changes were observed in ultrastructure of cortex and hippocampus CAI in brain damaged group. Conclusion Early intervention and rehabilitation training can improve the motor function in offspring with brain injury and reduce the expression of aquaporin-4 in damaged brain. PMID:26279808

Effect of educational preparation on the accuracy of linear growth measurement in pediatric primary care practices: results of a multicenter nursing study.

PubMed

Hench, Karen D; Shults, Justine; Benyi, Terri; Clow, Cheryl; Delaune, Joanne; Gilluly, Kathy; Johnson, Lydia; Johnson, Maryann; Rossiter, Katherine; McKnight-Menci, Heather; Shorkey, Doris; Waite, Fran; Weber, Colleen; Lipman, Terri H

2005-04-01

Consistently monitoring a child's linear growth is one of the least invasive, most sensitive tools to identify normal physiologic functioning and a healthy lifestyle. However, studies, mostly from the United Kingdom, indicate that children are frequently measured incorrectly. Inaccurate linear measurements may result in some children having undetected growth disorders whereas others with normal growth being referred for costly, unwarranted specialty evaluations. This study presents the secondary analysis of a primary study that used a randomized control study design to demonstrate that a didactic educational intervention resulted in significantly more children being measured accurately within eight pediatric practices. The secondary analysis explored the influence of the measurer's educational level on the outcome of accurate linear measurement. Results indicated that RNs were twice as likely as non-RNs to measure children accurately.

Linear regression analysis of survival data with missing censoring indicators.

PubMed

Wang, Qihua; Dinse, Gregg E

2011-04-01

Linear regression analysis has been studied extensively in a random censorship setting, but typically all of the censoring indicators are assumed to be observed. In this paper, we develop synthetic data methods for estimating regression parameters in a linear model when some censoring indicators are missing. We define estimators based on regression calibration, imputation, and inverse probability weighting techniques, and we prove all three estimators are asymptotically normal. The finite-sample performance of each estimator is evaluated via simulation. We illustrate our methods by assessing the effects of sex and age on the time to non-ambulatory progression for patients in a brain cancer clinical trial.

Application of the LSQR algorithm in non-parametric estimation of aerosol size distribution

NASA Astrophysics Data System (ADS)

He, Zhenzong; Qi, Hong; Lew, Zhongyuan; Ruan, Liming; Tan, Heping; Luo, Kun

2016-05-01

Based on the Least Squares QR decomposition (LSQR) algorithm, the aerosol size distribution (ASD) is retrieved in non-parametric approach. The direct problem is solved by the Anomalous Diffraction Approximation (ADA) and the Lambert-Beer Law. An optimal wavelength selection method is developed to improve the retrieval accuracy of the ASD. The proposed optimal wavelength set is selected by the method which can make the measurement signals sensitive to wavelength and decrease the degree of the ill-condition of coefficient matrix of linear systems effectively to enhance the anti-interference ability of retrieval results. Two common kinds of monomodal and bimodal ASDs, log-normal (L-N) and Gamma distributions, are estimated, respectively. Numerical tests show that the LSQR algorithm can be successfully applied to retrieve the ASD with high stability in the presence of random noise and low susceptibility to the shape of distributions. Finally, the experimental measurement ASD over Harbin in China is recovered reasonably. All the results confirm that the LSQR algorithm combined with the optimal wavelength selection method is an effective and reliable technique in non-parametric estimation of ASD.

SU-F-J-215: Non-Thermal Pulsed High Intensity Focused Ultrasound Therapy Combined with 5-Aminolevulinic Acid: An in Vivo Pilot Study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, B; He, W; Cvetkovic, D

Purpose: It has recently been shown that non-thermal pulsed high intensity focused ultrasound (pHIFU) has a cell-killing effect. The purpose of the study is to investigate the sonosensitizing effect of 5-Aminolevulinic Acid (5-ALA) in non-thermal pHIFU cancer therapy. Methods: FaDu human head and neck squamous cell carcinoma cells were injected subcutaneously in the flanks of nude mice. After one to two weeks, the tumors reached the volume of 112 ± 8 mm3 and were assigned randomly into a non-thermal pHIFU group (n=9) and a non-thermal sonodynamic therapy (pHIFU after 5-ALA administration) group (n=7). The pHIFU treatments (parameters: 1 MHz frequency;more » 25 W acoustic power; 0.1 duty cycle; 60 seconds duration) were delivered using an InSightec ExAblate 2000 system with a GE Signa 1.5T MR scanner. The mice in the non-thermal sonodynamic group received 5-ALA tail-vein injection 4 hours prior to the pHIFU treatment. The tumor growth was monitored using the CT scanner on a Sofie-Biosciences G8 PET/CT system. Results: The tumors in this study grew very aggressively and about 60% of the tumors in this study developed ulcerations at various stages. Tumor growth delay after treatments was observed by comparing the treated (n=9 in pHIFU group; n=7 in sonodynamic group) and untreated tumors (n=17). However, no statistically significant differences were found between the non-thermal pHIFU and non-thermal sonodynamic group. The mean normalized tumor volume of the untreated tumors on Day 7 after their first CT scans was 7.05 ± 0.54, while the normalized volume of the treated tumors on Day 7 after treatment was 5.89 ± 0.79 and 6.27 ± 0.47 for the sonodynamic group and pHIFU group, respectively. Conclusion: In this study, no significant sonosensitizing effects of 5-ALA were obtained on aggressive FaDu tumors despite apparent tumor growth delay in some mice treated with non-thermal sonodynamic therapy.« less

Diffusion of a particle in the spatially correlated exponential random energy landscape: Transition from normal to anomalous diffusion.

PubMed

Novikov, S V

2018-01-14

Diffusive transport of a particle in a spatially correlated random energy landscape having exponential density of states has been considered. We exactly calculate the diffusivity in the nondispersive quasi-equilibrium transport regime for the 1D transport model and found that for slow decaying correlation functions the diffusivity becomes singular at some particular temperature higher than the temperature of the transition to the true non-equilibrium dispersive transport regime. It means that the diffusion becomes anomalous and does not follow the usual ∝ t 1/2 law. In such situation, the fully developed non-equilibrium regime emerges in two stages: first, at some temperature there is the transition from the normal to anomalous diffusion, and then at lower temperature the average velocity for the infinite medium goes to zero, thus indicating the development of the true dispersive regime. Validity of the Einstein relation is discussed for the situation where the diffusivity does exist. We provide also some arguments in favor of conservation of the major features of the new transition scenario in higher dimensions.

Application of Multiple Imputation for Missing Values in Three-Way Three-Mode Multi-Environment Trial Data

PubMed Central

Tian, Ting; McLachlan, Geoffrey J.; Dieters, Mark J.; Basford, Kaye E.

2015-01-01

It is a common occurrence in plant breeding programs to observe missing values in three-way three-mode multi-environment trial (MET) data. We proposed modifications of models for estimating missing observations for these data arrays, and developed a novel approach in terms of hierarchical clustering. Multiple imputation (MI) was used in four ways, multiple agglomerative hierarchical clustering, normal distribution model, normal regression model, and predictive mean match. The later three models used both Bayesian analysis and non-Bayesian analysis, while the first approach used a clustering procedure with randomly selected attributes and assigned real values from the nearest neighbour to the one with missing observations. Different proportions of data entries in six complete datasets were randomly selected to be missing and the MI methods were compared based on the efficiency and accuracy of estimating those values. The results indicated that the models using Bayesian analysis had slightly higher accuracy of estimation performance than those using non-Bayesian analysis but they were more time-consuming. However, the novel approach of multiple agglomerative hierarchical clustering demonstrated the overall best performances. PMID:26689369

Application of Multiple Imputation for Missing Values in Three-Way Three-Mode Multi-Environment Trial Data.

PubMed

Tian, Ting; McLachlan, Geoffrey J; Dieters, Mark J; Basford, Kaye E

2015-01-01

It is a common occurrence in plant breeding programs to observe missing values in three-way three-mode multi-environment trial (MET) data. We proposed modifications of models for estimating missing observations for these data arrays, and developed a novel approach in terms of hierarchical clustering. Multiple imputation (MI) was used in four ways, multiple agglomerative hierarchical clustering, normal distribution model, normal regression model, and predictive mean match. The later three models used both Bayesian analysis and non-Bayesian analysis, while the first approach used a clustering procedure with randomly selected attributes and assigned real values from the nearest neighbour to the one with missing observations. Different proportions of data entries in six complete datasets were randomly selected to be missing and the MI methods were compared based on the efficiency and accuracy of estimating those values. The results indicated that the models using Bayesian analysis had slightly higher accuracy of estimation performance than those using non-Bayesian analysis but they were more time-consuming. However, the novel approach of multiple agglomerative hierarchical clustering demonstrated the overall best performances.

Progesterone Therapy, Endothelial Function and Cardiovascular Risk Factors: A 3-Month Randomized, Placebo-Controlled Trial in Healthy Early Postmenopausal Women

PubMed Central

Prior, Jerilynn C.; Elliott, Thomas G.; Norman, Eric; Stajic, Vesna; Hitchcock, Christine L.

2014-01-01

Background Progesterone is effective treatment for hot flushes/night sweats. The cardiovascular effects of progesterone therapy are unknown but evidence suggests that premenopausal normal estradiol with also normal progesterone levels may provide later cardiovascular protection. We compared the effects of progesterone to placebo on endothelial function, weight, blood pressure, metabolism, lipids, inflammation and coagulation. Methods and Results We conducted a randomized, double-blind, 3-month placebo-controlled trial of progesterone (300 mg daily) among 133 healthy postmenopausal women in Vancouver, Canada from 2003–2009. Endothelial function by venous occlusion plethysmography was a planned primary outcome. Enrolled women were 1–11 y since last menstruation, not using hormones (for >6 months), non-smoking, without diabetes, hypertension, heart disease or their medications. Randomized (1∶1) women (55±4 years, body mass index 25±3) initially had normal blood pressure, fasting lipid, glucose and electrocardiogram results. Endothelial function (% forearm blood flow above saline) was not changed with progesterone (487±189%, n = 18) compared with placebo (408±278%, n = 16) (95% CI diff [−74 to 232], P = 0.30). Progesterone (n = 65) and placebo (n = 47) groups had similar changes in systolic and diastolic blood pressure, resting heart rate, weight, body mass index, waist circumference, total cholesterol, low-density lipoprotein cholesterol and triglyceride levels. High-density lipoprotein was lower (−0.14 mmol/L, P = 0.001) on progesterone compared with placebo. Fasting glucose, hs-C-reactive protein, albumin and D-dimer changes were all comparable to placebo. Framingham General Cardiovascular Risk Profile scores were initially low and remained low with progesterone therapy and not statistically different from placebo. Conclusions Results indicate that progesterone has short-term cardiovascular safety. Endothelial function, weight, blood pressure, waist circumference, inflammation and coagulation were unchanged as were lipids except for HDL-C. The statistically significant decrease in HDL-C levels was not clinically important (based on lack of Cardiovascular Risk Profile change). Trial Registration ClinicalTrials.gov NCT00152438 PMID:24465425

Does Radiation Have a Role in Advanced Stage Hodgkin's or Non-Hodgkin Lymphoma?

PubMed

Specht, Lena

2016-01-01

Radiation therapy (RT) is one of the most effective agents available in the treatment of lymphomas. However, it is a local treatment, and today, with systemic treatments assuming a primary role for induction of response, RT is primarily used for consolidation. For advanced stage lymphomas, the indications for the use of RT have been questioned and debated, and proper randomized evidence is sparse. RT has significant long-term side effects, and the very extended RT fields of the past yielded unacceptable toxicity in many patients. Modern advanced imaging and conformal RT techniques now enable treatment of larger and anatomically more challenging target volumes with much less radiation to normal tissues and consequently much lower risks of long-term complications. The modern concept of involved site radiation therapy (ISRT) has now been accepted as standard in lymphomas. In advanced Hodgkin lymphoma (HL), RT to residual disease and/or initial bulk benefits some patients, depending on the chemotherapy regimen used. The more intensive the chemotherapy regimen, the fewer patients benefit from RT. In advanced aggressive non-Hodgkin lymphoma (NHL), most of the evidence comes from the most common type, the diffuse large B cell lymphoma (DLBCL). In patients treated with modern immunochemotherapy, RT to initial bulky disease or extralymphatic involvement is beneficial. For both HL and aggressive NHL, RT to residual masses after systemic treatment is of benefit. The role of PET in the evaluation and indication for RT to residual masses has not been tested in randomized trials. In advanced indolent NHL, very low dose RT offers excellent palliation with very few side effects. Modern RT in advanced lymphomas warrants further evaluation in randomized trials.

Group identification in Indonesian stock market

NASA Astrophysics Data System (ADS)

Nurriyadi Suparno, Ervano; Jo, Sung Kyun; Lim, Kyuseong; Purqon, Acep; Kim, Soo Yong

2016-08-01

The characteristic of Indonesian stock market is interesting especially because it represents developing countries. We investigate the dynamics and structures by using Random Matrix Theory (RMT). Here, we analyze the cross-correlation of the fluctuations of the daily closing price of stocks from the Indonesian Stock Exchange (IDX) between January 1, 2007, and October 28, 2014. The eigenvalue distribution of the correlation matrix consists of noise which is filtered out using the random matrix as a control. The bulk of the eigenvalue distribution conforms to the random matrix, allowing the separation of random noise from original data which is the deviating eigenvalues. From the deviating eigenvalues and the corresponding eigenvectors, we identify the intrinsic normal modes of the system and interpret their meaning based on qualitative and quantitative approach. The results show that the largest eigenvector represents the market-wide effect which has a predominantly common influence toward all stocks. The other eigenvectors represent highly correlated groups within the system. Furthermore, identification of the largest components of the eigenvectors shows the sector or background of the correlated groups. Interestingly, the result shows that there are mainly two clusters within IDX, natural and non-natural resource companies. We then decompose the correlation matrix to investigate the contribution of the correlated groups to the total correlation, and we find that IDX is still driven mainly by the market-wide effect.

Effects of oxytocin on high intensity focused ultrasound (HIFU) ablation of adenomysis: a prospective study.

PubMed

Zhang, Xin; Zou, Min; Zhang, Cai; He, Jia; Mao, Shihua; Wu, Qingrong; He, Min; Wang, Jian; Zhang, Ruitao; Zhang, Lian

2014-09-01

To investigate the effects of oxytocin on high-intensity focused ultrasound (HIFU) ablation for the treatment of adenomyosis. Eighty-six patients with adenomyosis from three hospitals were randomly assigned to the oxytocin group or control group for HIFU treatment. During HIFU treatment, 80 units of oxytocin was added in 500ml of 0.9% normal saline running at the rate of 2ml/min (0.32U/min) in the oxytocin group, while 0.9% normal saline was used in the control group. Both patients and HIFU operators were blinded to oxytocin or saline application. Treatment results, adverse effects were compared. When using oxytocin, the non-perfused volume (NPV) ratio was 80.7±11.6%, the energy-efficiency factor (EEF) was 8.1±9.9J/mm(3), and the sonication time required to ablate 1cm(3) was 30.0±36.0s/cm(3). When not using oxytocin, the non-perfused volume ratio was 70.8±16.7%, the EEF was 15.8±19.6J/mm(3), and the sonication time required to ablate 1cm(3) was 58.2±72.7S/cm(3). Significant difference in the NPV ratio, EEF, and the sonication time required to ablate 1cm(3) between the two groups was observed. No oxytocin related adverse effects occurred. Oxytocin could significantly decrease the energy for ablating adenomyosis with HIFU, safely enhance the treatment efficiency. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Central auditory processing effects induced by solvent exposure.

PubMed

Fuente, Adrian; McPherson, Bradley

2007-01-01

Various studies have demonstrated that organic solvent exposure may induce auditory damage. Studies conducted in workers occupationally exposed to solvents suggest, on the one hand, poorer hearing thresholds than in matched non-exposed workers, and on the other hand, central auditory damage due to solvent exposure. Taking into account the potential auditory damage induced by solvent exposure due to the neurotoxic properties of such substances, the present research aimed at studying the possible auditory processing disorder (APD), and possible hearing difficulties in daily life listening situations that solvent-exposed workers may acquire. Fifty workers exposed to a mixture of organic solvents (xylene, toluene, methyl ethyl ketone) and 50 non-exposed workers matched by age, gender and education were assessed. Only subjects with no history of ear infections, high blood pressure, kidney failure, metabolic and neurological diseases, or alcoholism were selected. The subjects had either normal hearing or sensorineural hearing loss, and normal tympanometric results. Hearing-in-noise (HINT), dichotic digit (DD), filtered speech (FS), pitch pattern sequence (PPS), and random gap detection (RGD) tests were carried out in the exposed and non-exposed groups. A self-report inventory of each subject's performance in daily life listening situations, the Amsterdam Inventory for Auditory Disability and Handicap, was also administered. Significant threshold differences between exposed and non-exposed workers were found at some of the hearing test frequencies, for both ears. However, exposed workers still presented normal hearing thresholds as a group (equal or better than 20 dB HL). Also, for the HINT, DD, PPS, FS and RGD tests, non-exposed workers obtained better results than exposed workers. Finally, solvent-exposed workers reported significantly more hearing complaints in daily life listening situations than non-exposed workers. It is concluded that subjects exposed to solvents may acquire an APD and thus the sole use of pure-tone audiometry is insufficient to assess hearing in solvent-exposed populations.

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

PubMed

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.

Fecal Microbiota Transplantation: Expanding Horizons for Clostridium difficile Infections and Beyond.

PubMed

Borody, Thomas J; Peattie, Debra; Mitchell, Scott W

2015-07-06

Fecal Microbiota Transplantation (FMT) methodology has been progressively refined over the past several years. The procedure has an extensive track record of success curing Clostridium difficile infection (CDI) with remarkably few adverse effects. It achieves similar levels of success whether the CDI occurs in the young or elderly, previously normal or profoundly ill patients, or those with CDI in Inflammatory Bowel Disease (IBD). While using FMT to treat CDI, however, we learned that using the procedure in other gastrointestinal (GI) diseases, such as IBD without CDI, generally fails to effect cure. To improve results in treating other non-CDI diseases, innovatively designed Randomized Controlled Trials (RCTs) will be required to address questions about mechanisms operating within particular diseases. Availability of orally deliverable FMT products, such as capsules containing lyophilised fecal microbiota, will simplify CDI treatment and open the door to convenient, prolonged FMT delivery to the GI tract and will likely deliver improved results in both CDI and non-CDI diseases.

Fecal Microbiota Transplantation: Expanding Horizons for Clostridium difficile Infections and Beyond

PubMed Central

Borody, Thomas J.; Peattie, Debra; Mitchell, Scott W.

2015-01-01

Fecal Microbiota Transplantation (FMT) methodology has been progressively refined over the past several years. The procedure has an extensive track record of success curing Clostridium difficile infection (CDI) with remarkably few adverse effects. It achieves similar levels of success whether the CDI occurs in the young or elderly, previously normal or profoundly ill patients, or those with CDI in Inflammatory Bowel Disease (IBD). While using FMT to treat CDI, however, we learned that using the procedure in other gastrointestinal (GI) diseases, such as IBD without CDI, generally fails to effect cure. To improve results in treating other non-CDI diseases, innovatively designed Randomized Controlled Trials (RCTs) will be required to address questions about mechanisms operating within particular diseases. Availability of orally deliverable FMT products, such as capsules containing lyophilised fecal microbiota, will simplify CDI treatment and open the door to convenient, prolonged FMT delivery to the GI tract and will likely deliver improved results in both CDI and non-CDI diseases. PMID:27025624

Effects of caffeine on fractional flow reserve values measured using intravenous adenosine triphosphate.

PubMed

Nakayama, Masafumi; Chikamori, Taishiro; Uchiyama, Takashi; Kimura, Yo; Hijikata, Nobuhiro; Ito, Ryosuke; Yuhara, Mikio; Sato, Hideaki; Kobori, Yuichi; Yamashina, Akira

2018-04-01

We investigated the effects of caffeine intake on fractional flow reserve (FFR) values measured using intravenous adenosine triphosphate (ATP) before cardiac catheterization. Caffeine is a competitive antagonist for adenosine receptors; however, it is unclear whether this antagonism affects FFR values. Patients were evenly randomized into 2 groups preceding the FFR study. In the caffeine group (n = 15), participants were given coffee containing 222 mg of caffeine 2 h before the catheterization. In the non-caffeine group (n = 15), participants were instructed not to take any caffeine-containing drinks or foods for at least 12 h before the catheterization. FFR was performed in patients with more than intermediate coronary stenosis using the intravenous infusion of ATP at 140 μg/kg/min (normal dose) and 170 μg/kg/min (high dose), and the intracoronary infusion of papaverine. FFR was followed for 30 s after maximal hyperemia. In the non-caffeine group, the FFR values measured with ATP infusion were not significantly different from those measured with papaverine infusion. However, in the caffeine group, the FFR values were significantly higher after ATP infusion than after papaverine infusion (P = 0.002 and P = 0.007, at normal and high dose ATP vs. papaverine, respectively). FFR values with ATP infusion were significantly increased 30 s after maximal hyperemia (P = 0.001 and P < 0.001 for normal and high dose ATP, respectively). The stability of the FFR values using papaverine showed no significant difference between the 2 groups. Caffeine intake before the FFR study affected FFR values and their stability. These effects could not be reversed by an increased ATP dose.

Is the Non-Dipole Magnetic Field Random?

NASA Technical Reports Server (NTRS)

Walker, Andrew D.; Backus, George E.

1996-01-01

Statistical modelling of the Earth's magnetic field B has a long history. In particular, the spherical harmonic coefficients of scalar fields derived from B can be treated as Gaussian random variables. In this paper, we give examples of highly organized fields whose spherical harmonic coefficients pass tests for independent Gaussian random variables. The fact that coefficients at some depth may be usefully summarized as independent samples from a normal distribution need not imply that there really is some physical, random process at that depth. In fact, the field can be extremely structured and still be regarded for some purposes as random. In this paper, we examined the radial magnetic field B(sub r) produced by the core, but the results apply to any scalar field on the core-mantle boundary (CMB) which determines B outside the CMB.

Lack of efficacy of a reduced microparticle diet in a multi-centred trial of patients with active Crohn's disease.

PubMed

Lomer, Miranda C E; Grainger, Stephen L; Ede, Roland; Catterall, Adrian P; Greenfield, Simon M; Cowan, Russell E; Vicary, F Robin; Jenkins, Anthony P; Fidler, Helen; Harvey, Rory S; Ellis, Richard; McNair, Alistair; Ainley, Colin C; Thompson, Richard P H; Powell, Jonathan J

2005-03-01

Dietary microparticles, which are bacteria-sized and non-biological, found in the modern Western diet, have been implicated in both the aetiology and pathogenesis of Crohn's disease. Following on from the findings of a previous pilot study, we aimed to confirm whether a reduction in the amount of dietary microparticles facilitates induction of remission in patients with active Crohn's disease, in a single-blind, randomized, multi-centre, placebo controlled trial. Eighty-three patients with active Crohn's disease were randomly allocated in a 2 x 2 factorial design to a diet low or normal in microparticles and/or calcium for 16 weeks. All patients received a reducing dose of prednisolone for 6 weeks. Outcome measures were Crohn's disease activity index, Van Hees index, quality of life and a series of objective measures of inflammation including erythrocyte sedimentation rate, C-reactive protein, intestinal permeability and faecal calprotectin. After 16 weeks patients returned to their normal diet and were followed up for a further 36 weeks. Dietary manipulation provided no added effect to corticosteroid treatment on any of the outcome measures during the dietary trial (16 weeks) or follow-up (to 1 year); e.g., for logistic regression of Crohn's disease activity index based rates of remission (P=0.1) and clinical response (P=0.8), in normal versus low microparticle groups. Our adequately powered and carefully controlled dietary trial found no evidence that reducing microparticle intake aids remission in active Crohn's disease.

The effect of signal variability on the histograms of anthropomorphic channel outputs: factors resulting in non-normally distributed data

NASA Astrophysics Data System (ADS)

Elshahaby, Fatma E. A.; Ghaly, Michael; Jha, Abhinav K.; Frey, Eric C.

2015-03-01

Model Observers are widely used in medical imaging for the optimization and evaluation of instrumentation, acquisition parameters and image reconstruction and processing methods. The channelized Hotelling observer (CHO) is a commonly used model observer in nuclear medicine and has seen increasing use in other modalities. An anthropmorphic CHO consists of a set of channels that model some aspects of the human visual system and the Hotelling Observer, which is the optimal linear discriminant. The optimality of the CHO is based on the assumption that the channel outputs for data with and without the signal present have a multivariate normal distribution with equal class covariance matrices. The channel outputs result from the dot product of channel templates with input images and are thus the sum of a large number of random variables. The central limit theorem is thus often used to justify the assumption that the channel outputs are normally distributed. In this work, we aim to examine this assumption for realistically simulated nuclear medicine images when various types of signal variability are present.

Crossover from impurity-controlled to granular superconductivity in (TMTSF) 2ClO4

NASA Astrophysics Data System (ADS)

Yonezawa, Shingo; Marrache-Kikuchi, Claire A.; Bechgaard, Klaus; Jérome, Denis

2018-01-01

Using a proper cooling procedure, a controllable amount of nonmagnetic structural disorder can be introduced at low temperature in (TMTSF) 2ClO4 . Here we performed simultaneous measurements of transport and magnetic properties of (TMTSF) 2ClO4 in its normal and superconducting states, while finely covering three orders of magnitude of the cooling rate around the anion ordering temperature. Our result reveals, with increasing density of disorder, the existence of a crossover between homogeneous defect-controlled d -wave superconductivity and granular superconductivity. At slow cooling rates, with small amount of disorder, the evolution of superconducting properties is well described with the Abrikosov-Gorkov theory, providing further confirmation of non-s -wave pairing in this compound. In contrast, at fast cooling rates, zero resistance and diamagnetic shielding are achieved through a randomly distributed network of superconducting puddles embedded in a normal conducting background and interconnected by proximity effect coupling. The temperature dependence of the ac complex susceptibility reveals features typical for a network of granular superconductors. This makes (TMTSF) 2ClO4 a model system for granular superconductivity where the grain size and their concentration are tunable within the same sample.

Spectroscopic diagnosis of laryngeal carcinoma using near-infrared Raman spectroscopy and random recursive partitioning ensemble techniques.

PubMed

Teh, Seng Khoon; Zheng, Wei; Lau, David P; Huang, Zhiwei

2009-06-01

In this work, we evaluated the diagnostic ability of near-infrared (NIR) Raman spectroscopy associated with the ensemble recursive partitioning algorithm based on random forests for identifying cancer from normal tissue in the larynx. A rapid-acquisition NIR Raman system was utilized for tissue Raman measurements at 785 nm excitation, and 50 human laryngeal tissue specimens (20 normal; 30 malignant tumors) were used for NIR Raman studies. The random forests method was introduced to develop effective diagnostic algorithms for classification of Raman spectra of different laryngeal tissues. High-quality Raman spectra in the range of 800-1800 cm(-1) can be acquired from laryngeal tissue within 5 seconds. Raman spectra differed significantly between normal and malignant laryngeal tissues. Classification results obtained from the random forests algorithm on tissue Raman spectra yielded a diagnostic sensitivity of 88.0% and specificity of 91.4% for laryngeal malignancy identification. The random forests technique also provided variables importance that facilitates correlation of significant Raman spectral features with cancer transformation. This study shows that NIR Raman spectroscopy in conjunction with random forests algorithm has a great potential for the rapid diagnosis and detection of malignant tumors in the larynx.

A prospective, randomized, double-blind study, comparing unirradiated to irradiated white blood cell transfusions in acute leukemia patients

PubMed Central

Freireich, E J; Lichtiger, B; Mattiuzzi, G; Martinez, F; Reddy, V; Kyle Wathen, J

2013-01-01

A prospective, randomized double-blind study comparing the effects of irradiated and unirradiated white blood cells was conducted in 108 acute leukemia patients with life-threatening infections, refractory to antibiotics. The study demonstrated no significant improvement in 30-day survival or overall survival. Transfusion of unirradiated white cells did not compromise the patient's opportunity to undergo allogeneic stem cell transplant, nor the success rate or overall survival after allogeneic transplant. The important positive finding in this study was that the unirradiated white cells produced a significantly higher increment in circulating granulocytes and in a higher proportion of patients granulocyte count exceeded 1000 per microliter, approaching normal concentrations. The increase in the number and the improved survival of the unirradiated granulocytes suggest that this procedure might potentially be a method to improve the utility of granulocyte transfusions and merits further investigation. The study demonstrated non-inferiority for unirradiated white cells. There were no harmful effects such as graft-versus-host disease, indicating that such studies would be safe to conduct in the future. PMID:23072780

A randomized clinical trial of the efficacy of single versus double-daily dose of oral iron for prevention of iron deficiency anemia in women with twin gestations.

PubMed

Ali, Mohammed K; Abbas, Ahmed M; Abdelmagied, Ahmed M; Mohammed, Ghada E; Abdalmageed, Osama S

2017-12-01

The study aims to assess the efficacy of single versus double-daily oral iron dose on prevention of iron deficiency anemia in women with twin gestations. A randomized controlled trial (NCT02858505) conducted at Woman's Health Hospital, Assiut, Egypt, between August 2015 and June 2016 included 120 non-anemic pregnant women with twin gestations in the first trimester. Women were randomly assigned to either group I (27 mg elemental iron) or group II (54 mg elemental iron) daily starting from 12 weeks of pregnancy till 36 weeks. The primary outcomes included the mean level of hemoglobin, hematocrit and serum ferritin at 36 weeks' gestation. Both iron doses maintained the mean hemoglobin and hematocrit within the normal level from 12 weeks to 36 weeks (p = 0.378 and p = 0.244, respectively). However, the mean serum ferritin level was higher in group II than group I (p = 0.000) at 36 weeks' gestation. Moreover, women in group II reported more side effects than group I at 36 weeks' gestation. Doubling the prophylactic iron dose is comparable to single dose in the prevention of iron deficiency anemia among women with twin gestations with more side effects.

ITALICS: an algorithm for normalization and DNA copy number calling for Affymetrix SNP arrays.

PubMed

Rigaill, Guillem; Hupé, Philippe; Almeida, Anna; La Rosa, Philippe; Meyniel, Jean-Philippe; Decraene, Charles; Barillot, Emmanuel

2008-03-15

Affymetrix SNP arrays can be used to determine the DNA copy number measurement of 11 000-500 000 SNPs along the genome. Their high density facilitates the precise localization of genomic alterations and makes them a powerful tool for studies of cancers and copy number polymorphism. Like other microarray technologies it is influenced by non-relevant sources of variation, requiring correction. Moreover, the amplitude of variation induced by non-relevant effects is similar or greater than the biologically relevant effect (i.e. true copy number), making it difficult to estimate non-relevant effects accurately without including the biologically relevant effect. We addressed this problem by developing ITALICS, a normalization method that estimates both biological and non-relevant effects in an alternate, iterative manner, accurately eliminating irrelevant effects. We compared our normalization method with other existing and available methods, and found that ITALICS outperformed these methods for several in-house datasets and one public dataset. These results were validated biologically by quantitative PCR. The R package ITALICS (ITerative and Alternative normaLIzation and Copy number calling for affymetrix Snp arrays) has been submitted to Bioconductor.

Random attractor of non-autonomous stochastic Boussinesq lattice system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhao, Min, E-mail: zhaomin1223@126.com; Zhou, Shengfan, E-mail: zhoushengfan@yahoo.com

2015-09-15

In this paper, we first consider the existence of tempered random attractor for second-order non-autonomous stochastic lattice dynamical system of nonlinear Boussinesq equations effected by time-dependent coupled coefficients and deterministic forces and multiplicative white noise. Then, we establish the upper semicontinuity of random attractors as the intensity of noise approaches zero.

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

PubMed

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.

Correction of confounding bias in non-randomized studies by appropriate weighting.

PubMed

Schmoor, Claudia; Gall, Christine; Stampf, Susanne; Graf, Erika

2011-03-01

In non-randomized studies, the assessment of a causal effect of treatment or exposure on outcome is hampered by possible confounding. Applying multiple regression models including the effects of treatment and covariates on outcome is the well-known classical approach to adjust for confounding. In recent years other approaches have been promoted. One of them is based on the propensity score and considers the effect of possible confounders on treatment as a relevant criterion for adjustment. Another proposal is based on using an instrumental variable. Here inference relies on a factor, the instrument, which affects treatment but is thought to be otherwise unrelated to outcome, so that it mimics randomization. Each of these approaches can basically be interpreted as a simple reweighting scheme, designed to address confounding. The procedures will be compared with respect to their fundamental properties, namely, which bias they aim to eliminate, which effect they aim to estimate, and which parameter is modelled. We will expand our overview of methods for analysis of non-randomized studies to methods for analysis of randomized controlled trials and show that analyses of both study types may target different effects and different parameters. The considerations will be illustrated using a breast cancer study with a so-called Comprehensive Cohort Study design, including a randomized controlled trial and a non-randomized study in the same patient population as sub-cohorts. This design offers ideal opportunities to discuss and illustrate the properties of the different approaches. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A prospective randomized trial of two solutions for intrapartum amnioinfusion: effects on fetal electrolytes, osmolality, and acid-base status.

PubMed

Pressman, E K; Blakemore, K J

1996-10-01

Our purpose was to compare the effects of intrapartum amnioinfusion with normal saline solution versus lactated Ringer's solution plus physiologic glucose on neonatal electrolytes and acid-base balance. Patients undergoing amnioinfusion for obstetric indications were randomized to receive normal saline solution or lactated Ringer's solution plus physiologic glucose at standardized amnioinfusion rates. Data were collected prospectively on maternal demographics, course of labor, and maternal and neonatal outcome. Arterial cord blood was obtained for analysis of electrolytes, glucose, osmolality, lactic acid, and blood gases. Control subjects with normal fetal heart rate patterns, and clear amniotic fluid not receiving amnioinfusion were studied concurrently. Data were collected on 59 patients (21 normal saline solution, 18 lactated Ringer's solution plus physiologic glucose, and 20 controls). Maternal demographics, course of labor, and neonatal outcome were similar in all three groups. Cesarean sections were performed more often in the amnioinfusion groups (33.3% for normal saline solution, 38.9% for lactated Ringer's solution plus physiologic glucose) than in the control group (5.0%), p < 0.05. Cord arterial electrolytes, glucose, osmolality, lactic acid, and blood gases were not altered by amnioinfusion with either solution. Intrapartum amnioinfusion with normal saline solution or lactated Ringer's solution plus physiologic glucose has no effect on neonatal electrolytes or acid-base balance.

Alternate methods for FAAT S-curve generation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kaufman, A.M.

The FAAT (Foreign Asset Assessment Team) assessment methodology attempts to derive a probability of effect as a function of incident field strength. The probability of effect is the likelihood that the stress put on a system exceeds its strength. In the FAAT methodology, both the stress and strength are random variables whose statistical properties are estimated by experts. Each random variable has two components of uncertainty: systematic and random. The systematic uncertainty drives the confidence bounds in the FAAT assessment. Its variance can be reduced by improved information. The variance of the random uncertainty is not reducible. The FAAT methodologymore » uses an assessment code called ARES to generate probability of effect curves (S-curves) at various confidence levels. ARES assumes log normal distributions for all random variables. The S-curves themselves are log normal cumulants associated with the random portion of the uncertainty. The placement of the S-curves depends on confidence bounds. The systematic uncertainty in both stress and strength is usually described by a mode and an upper and lower variance. Such a description is not consistent with the log normal assumption of ARES and an unsatisfactory work around solution is used to obtain the required placement of the S-curves at each confidence level. We have looked into this situation and have found that significant errors are introduced by this work around. These errors are at least several dB-W/cm{sup 2} at all confidence levels, but they are especially bad in the estimate of the median. In this paper, we suggest two alternate solutions for the placement of S-curves. To compare these calculational methods, we have tabulated the common combinations of upper and lower variances and generated the relevant S-curves offsets from the mode difference of stress and strength.« less

Study on probability distribution of prices in electricity market: A case study of zhejiang province, china

NASA Astrophysics Data System (ADS)

Zhou, H.; Chen, B.; Han, Z. X.; Zhang, F. Q.

2009-05-01

The study on probability density function and distribution function of electricity prices contributes to the power suppliers and purchasers to estimate their own management accurately, and helps the regulator monitor the periods deviating from normal distribution. Based on the assumption of normal distribution load and non-linear characteristic of the aggregate supply curve, this paper has derived the distribution of electricity prices as the function of random variable of load. The conclusion has been validated with the electricity price data of Zhejiang market. The results show that electricity prices obey normal distribution approximately only when supply-demand relationship is loose, whereas the prices deviate from normal distribution and present strong right-skewness characteristic. Finally, the real electricity markets also display the narrow-peak characteristic when undersupply occurs.

Glucocorticoids decrease body weight and food intake and inhibit appetite regulatory peptide expression in the hypothalamus of rats

PubMed Central

LIU, XIAO-YAN; SHI, JIAN-HUA; DU, WEN-HUA; FAN, YAN-PING; HU, XIAO-LEI; ZHANG, CHEN-CHEN; XU, HUAN-BAI; MIAO, YAN-JUN; ZHOU, HAI-YAN; XIANG, PING; CHEN, FENG-LING

2011-01-01

The aim of the present study was to investigate the effects of glucocorticoids (GCs) on appetite and gene expression of the hypothalamic appetite regulatory peptides, neuropeptide Y (NPY), agouti-related protein (AGRP) and cocaine and amphetamine-regulated transcript (CART), in non-obese and obese rats. Both non-obese and obese rats were randomly assigned to three groups: normal saline, low- and high-dose GC groups (NSG, LDG and HDG, respectively), which received an intraperitoneal injection with normal saline (0.2 ml/100 g) or hydrocortisone sodium succinate at 5 and 15 mg/kg, respectively, for 20 days. The expression levels of NPY, AGRP and CART mRNA in the hypothalamus were measured by real-time quantitative PCR. Non-obese and obese rats were found to undergo weight loss after GC injection, and a higher degree of weight loss was observed in the HDG rats. The average and cumulative food intakes in the obese and non-obese rats injected with high-dose GC were lower compared to that in the NSG (p<0.05). mRNA expression levels of the orexigenic neuropeptides, NPY and AGRP, and the anorexigenic neuropeptide, CART, were significantly lower in the HDG than levels in the NSG for both the obese and non-obese rats (p<0.05). GC treatment decreased appetite and body weight, induced apparent glucolipid metabolic disturbances and hyperinsulinemia, while down-regulated mRNA expression levels of the orexigenic neuropeptides, NPY and AGRP, and anorexigenic neuropeptide, CART, in the hypothalamus in the rats. The mechanism which induces this neuropeptide expression requires further study. PMID:22977608

Effect of the aqueous extract of Foeniculum vulgare (fennel) on the kidney in experimental PCOS female rats.

PubMed

Sadrefozalayi, Somayyeh; Farokhi, Farah

2014-03-01

Foeniculum vulgare seed (F. vulgare) is an herbal plant which is used with phytoestrogene compounds for polycystic ovary syndrome (PCOS) treatment. In this research, renoprotective effect of the aqueous extract of Foeniculum vulgare (AEF) in experimental PCOS female rats is studied. Forty female rats were randomly divided into five groups. The first group served as control, was injected with an equivalent volume (0.2 ml) of normal saline, and received normal diet. Animals in the second group were non poly cystic ovary syndrome (PCOS) rats which were treated with intragastric administration of aqueous extract of F. vulgare (150 mg/kg b.w.). In the third group, the rats were treated with intraperitoneal injection of estradiolvalerate (EV) (4 mg in 0.2 ml of sesame oil). The fourth groups were treated with EV and AEF (150mg/kg bw) with the same route. The fifth groups were treated with EV and AEF (100mg/kg bw). After 4 weeks of study, all of the rats were sacrificed, their kidneys tissues were processed for light microscopy, and some biochemical parameters of serum were measured. The mean values of blood urea nitrogen in PCOS rats treated with low dose of AEF and EV and non-treated, was significantly (p<0.05) increased compared with non-PCOS and PCOS rats treated with high dose of AEF. Moreover, histopathological changes of kidney samples were comparable in PCOS rats with respect to treated groups with AEF. Aqueous extract of fennel seed showed the beneficial effect (especially at dose of 150 mg/kg b.w.) on renal function in PCOS rats.

Shunting for normal pressure hydrocephalus (NPH).

PubMed

Esmonde, T; Cooke, S

2002-01-01

Since the condition was first described in 1965, the syndrome of normal pressure hydrocephalus (NPH) has conventionally been managed by placement of a cerebrospinal fluid (CSF) shunt. To determine the effectiveness of shunting procedures in promoting stability or improvement in the neurological symptoms and signs of NPH. The trials were identified from a search of the Specialized Register of the Cochrane Dementia and Cognitive Improvement Group on 26 June 2001 using the terms 'shunt*' and 'normal pressure hydrocephalus'. Studies included for analysis were those involving the placement of a CSF shunt for the treatment of NPH as part of a randomized controlled trial. No data matching the selection criteria were found. No randomized controlled trials of shunt placement versus no shunt were found. There is no evidence to indicate whether placement of a shunt is effective in the management of NPH.

[Effect of glutamine on small intestinal repair in weanling rats after chronic diarrhea].

PubMed

Huang, Zu-xiong; Ye, Li-yan; Zheng, Zhi-yong; Chen, Xin-min; Ren, Rong-na; Tong, Guo-yuan

2005-05-01

To investigate the nutrient effect of glutamine on small intestinal repair in weanling rats after chronic diarrhea. Forty 21-day-old wistar rats were randomly divided into five groups (8 in each). Animal model of chronic diarrhea was induced by a lactose enriched diet in the weanling Wistar rat, normal control group was fed with a standard semipurified diet, and after 14 days the rats in both groups were killed to test the establishment of the model. After the establishment of the model, the other groups were fed with the standard semipurified diet to recover for 7 days, and were randomly divided into three groups: non-intervention group, glutamine (Gln)-intervention group and control group. Glutamine concentrations in blood was detected by high-performance liquid chromatography (HPLC). Morphological changes including villus height and villus surface area of the jejunum were measured under a light microscope and electron microscope, expression of proliferating cell nuclear antigen (PCNA) as an index of cell proliferation was observed using immunohistochemical staining and image analysis. The diarrhea rate in model group was 100 percent, average diarrhea index was 1.16 +/- 0.06, but both diarrhea rate and average diarrhea index in control group were 0 (P < 0.01), which affirmed establishment of the model. There was significant decrease of body weight, plasma Gln concentration, villus height, villus surface area and expression of PCNA in non-intervened group compared with the control group (P < 0.01). There was still significant decrease of body weight, villus height and villus surface area in Gln-intervened group compared with control group (P < 0.01), but plasma Gln concentration and expression of PCNA in Gln-intervened group had recovered to normal (P > 0.05). And compared with non-intervened group, except for body weight (P > 0.05), plasma glutamine, villus height, villus surface area and expression of PCNA were all significantly increased in Gln-intervened group. Chronic diarrhea can induce malnutrition and reduce the villus height, villus surface area, expression of PCNA and plasm glutamine concentration. Oral glutamine could improve the proliferation of crypt cell and promote repair of intestinal mucosa after chronic diarrhea.

Modeling Longitudinal Data Containing Non-Normal Within Subject Errors

NASA Technical Reports Server (NTRS)

Feiveson, Alan; Glenn, Nancy L.

2013-01-01

The mission of the National Aeronautics and Space Administration’s (NASA) human research program is to advance safe human spaceflight. This involves conducting experiments, collecting data, and analyzing data. The data are longitudinal and result from a relatively few number of subjects; typically 10 – 20. A longitudinal study refers to an investigation where participant outcomes and possibly treatments are collected at multiple follow-up times. Standard statistical designs such as mean regression with random effects and mixed–effects regression are inadequate for such data because the population is typically not approximately normally distributed. Hence, more advanced data analysis methods are necessary. This research focuses on four such methods for longitudinal data analysis: the recently proposed linear quantile mixed models (lqmm) by Geraci and Bottai (2013), quantile regression, multilevel mixed–effects linear regression, and robust regression. This research also provides computational algorithms for longitudinal data that scientists can directly use for human spaceflight and other longitudinal data applications, then presents statistical evidence that verifies which method is best for specific situations. This advances the study of longitudinal data in a broad range of applications including applications in the sciences, technology, engineering and mathematics fields.

Cognitive Effects of Stimulant, Guanfacine, and Combined Treatment in Child and Adolescent Attention-Deficit/Hyperactivity Disorder

PubMed Central

Bilder, Robert M.; Loo, Sandra; McGough, James J.; Whelan, Fiona; Hellemann, Gerhard; Sugar, Catherine; Del’Homme, Melissa; Sturm, Alexandra; Cowen, Jennifer; Hanada, Grant; McCracken, James T.

2016-01-01

Objective Psychostimulants are partially effective in reducing cognitive dysfunction associated with attention-deficit/hyperactivity disorder (ADHD). Cognitive effects of guanfacine, an alternative treatment, are poorly understood. Given its distinct action on α2A receptors, guanfacine may have different or complementary effects relative to stimulants. This study tested stimulant and guanfacine monotherapies relative to combined treatment on cognitive functions important in ADHD. Method Children with ADHD (n = 182; age 7–14 years) completed an eight-week double blind randomized controlled trial with three arms: d-methylphenidate (DMPH), guanfacine (GUAN), or combination treatment with DMPH and GUAN (COMB). A non-clinical comparison group (n = 93) had baseline testing, and a subset was re-tested 8 weeks later (n = 38). Analyses examined treatment effects in four cognitive domains (working memory, response inhibition, reaction time, and reaction time variability) constructed from 20 variables. Results The ADHD group showed impaired working memory relative to the non-clinical comparison group (effect size = −0.53 SD units). The treatments differed in effects on working memory but not other cognitive domains. Combination treatment improved working memory more than GUAN, but was not significantly better than DMPH alone. Treatment did not fully normalize the initial deficit in ADHD relative to the comparison group. Conclusion Combined treatment with DMPH and GUAN yielded greater improvements in working memory than placebo or GUAN alone, but the combined treatment was not superior to DMPH alone, and did not extend to other cognitive domains. Although GUAN may be a useful add-on treatment to psychostimulants, additional strategies appear necessary to achieve normalization of cognitive function in ADHD. Clinical trial registration information Single Versus Combination Medication Treatment for Children With Attention Deficit Hyperactivity Disorder; http://clinicaltrials.gov/; NCT00429273 PMID:27453080

Correlation of circular RNA abundance with proliferation--exemplified with colorectal and ovarian cancer, idiopathic lung fibrosis, and normal human tissues.

PubMed

Bachmayr-Heyda, Anna; Reiner, Agnes T; Auer, Katharina; Sukhbaatar, Nyamdelger; Aust, Stefanie; Bachleitner-Hofmann, Thomas; Mesteri, Ildiko; Grunt, Thomas W; Zeillinger, Robert; Pils, Dietmar

2015-01-27

Circular RNAs are a recently (re-)discovered abundant RNA species with presumed function as miRNA sponges, thus part of the competing endogenous RNA network. We analysed the expression of circular and linear RNAs and proliferation in matched normal colon mucosa and tumour tissues. We predicted >1,800 circular RNAs and proved the existence of five randomly chosen examples using RT-qPCR. Interestingly, the ratio of circular to linear RNA isoforms was always lower in tumour compared to normal colon samples and even lower in colorectal cancer cell lines. Furthermore, this ratio correlated negatively with the proliferation index. The correlation of global circular RNA abundance (the circRNA index) and proliferation was validated in a non-cancerous proliferative disease, idiopathic pulmonary fibrosis, ovarian cancer cells compared to cultured normal ovarian epithelial cells, and 13 normal human tissues. We are the first to report a global reduction of circular RNA abundance in colorectal cancer cell lines and cancer compared to normal tissues and discovered a negative correlation of global circular RNA abundance and proliferation. This negative correlation seems to be a general principle in human tissues as validated with three different settings. Finally, we present a simple model how circular RNAs could accumulate in non-proliferating cells.

Correlation of circular RNA abundance with proliferation – exemplified with colorectal and ovarian cancer, idiopathic lung fibrosis, and normal human tissues

PubMed Central

Bachmayr-Heyda, Anna; Reiner, Agnes T.; Auer, Katharina; Sukhbaatar, Nyamdelger; Aust, Stefanie; Bachleitner-Hofmann, Thomas; Mesteri, Ildiko; Grunt, Thomas W.; Zeillinger, Robert; Pils, Dietmar

2015-01-01

Circular RNAs are a recently (re-)discovered abundant RNA species with presumed function as miRNA sponges, thus part of the competing endogenous RNA network. We analysed the expression of circular and linear RNAs and proliferation in matched normal colon mucosa and tumour tissues. We predicted >1,800 circular RNAs and proved the existence of five randomly chosen examples using RT-qPCR. Interestingly, the ratio of circular to linear RNA isoforms was always lower in tumour compared to normal colon samples and even lower in colorectal cancer cell lines. Furthermore, this ratio correlated negatively with the proliferation index. The correlation of global circular RNA abundance (the circRNA index) and proliferation was validated in a non-cancerous proliferative disease, idiopathic pulmonary fibrosis, ovarian cancer cells compared to cultured normal ovarian epithelial cells, and 13 normal human tissues. We are the first to report a global reduction of circular RNA abundance in colorectal cancer cell lines and cancer compared to normal tissues and discovered a negative correlation of global circular RNA abundance and proliferation. This negative correlation seems to be a general principle in human tissues as validated with three different settings. Finally, we present a simple model how circular RNAs could accumulate in non-proliferating cells. PMID:25624062

Plateau inflation from random non-minimal coupling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Broy, Benedict J.; Coone, Dries; Theoretische Natuurkunde,Vrije Universiteit Brussel and The International Solvay Institutes,Pleinlaan 2, B-1050 Brussels

A generic non-minimal coupling can push any higher-order terms of the scalar potential sufficiently far out in field space to yield observationally viable plateau inflation. We provide analytic and numerical evidence that this generically happens for a non-minimal coupling strength ξ of the order N{sub e}{sup 2}. In this regime, the non-minimally coupled field is sub-Planckian during inflation and is thus protected from most higher-order terms. For larger values of ξ, the inflationary predictions converge towards the sweet spot of PLANCK. The latter includes ξ≃10{sup 4} obtained from CMB normalization arguments, thus providing a natural explanation for the inflationary observablesmore » measured.« less

Conditions for the Emergence of Shared Norms in Populations with Incompatible Preferences

PubMed Central

Helbing, Dirk; Yu, Wenjian; Opp, Karl-Dieter; Rauhut, Heiko

2014-01-01

Understanding norms is a key challenge in sociology. Nevertheless, there is a lack of dynamical models explaining how one of several possible behaviors is established as a norm and under what conditions. Analysing an agent-based model, we identify interesting parameter dependencies that imply when two behaviors will coexist or when a shared norm will emerge in a heterogeneous society, where different populations have incompatible preferences. Our model highlights the importance of randomness, spatial interactions, non-linear dynamics, and self-organization. It can also explain the emergence of unpopular norms that do not maximize the collective benefit. Furthermore, we compare behavior-based with preference-based punishment and find interesting results concerning hypocritical punishment. Strikingly, pressuring others to perform the same public behavior as oneself is more effective in promoting norms than pressuring others to meet one’s own private preference. Finally, we show that adaptive group pressure exerted by randomly occuring, local majorities may create norms under conditions where different behaviors would normally coexist. PMID:25166137

Effect of Ginkgo biloba on visual field and contrast sensitivity in Chinese patients with normal tension glaucoma: a randomized, crossover clinical trial.

PubMed

Guo, Xinxing; Kong, Xiangbin; Huang, Rui; Jin, Ling; Ding, Xiaohu; He, Mingguang; Liu, Xing; Patel, Mehul Chimanlal; Congdon, Nathan G

2014-01-07

We evaluated the effect of ginkgo biloba extract on visual field defect and contrast sensitivity in a Chinese cohort with normal tension glaucoma. In this prospective, randomized, placebo-controlled crossover study, patients newly diagnosed with normal tension glaucoma, either in a tertiary glaucoma clinic (n = 5) or in a cohort undergoing routine general physical examinations in a primary care clinic (n = 30), underwent two 4-week phases of treatment, separated by a washout period of 8 weeks. Randomization determined whether ginkgo biloba extract (40 mg, 3 times per day) or placebo (identical-appearing tablets) was received first. Primary outcomes were change in contrast sensitivity and mean deviation on 24-2 SITA standard visual field testing, while secondary outcomes included IOP and self-reported adverse events. A total of 35 patients with mean age 63.7 (6.5) years were randomized to the ginkgo biloba extract-placebo (n = 18) or the placebo-ginkgo biloba extract (n = 17) sequence. A total of 28 patients (80.0%, 14 in each group) who completed testing did not differ at baseline in age, sex, visual field mean deviation, contrast sensitivity, IOP, or blood pressure. Changes in visual field and contrast sensitivity did not differ by treatment received or sequence (P > 0.2 for all). Power to have detected a difference in mean defect as large as previously reported was 80%. In contrast to some previous reports, ginkgo biloba extract treatment had no effect on mean defect or contrast sensitivity in this group of normal tension glaucoma patients. (http://www.chictr.org number, ChiCTR-TRC-08000724).

Multidimensional Normalization to Minimize Plate Effects of Suspension Bead Array Data.

PubMed

Hong, Mun-Gwan; Lee, Woojoo; Nilsson, Peter; Pawitan, Yudi; Schwenk, Jochen M

2016-10-07

Enhanced by the growing number of biobanks, biomarker studies can now be performed with reasonable statistical power by using large sets of samples. Antibody-based proteomics by means of suspension bead arrays offers one attractive approach to analyze serum, plasma, or CSF samples for such studies in microtiter plates. To expand measurements beyond single batches, with either 96 or 384 samples per plate, suitable normalization methods are required to minimize the variation between plates. Here we propose two normalization approaches utilizing MA coordinates. The multidimensional MA (multi-MA) and MA-loess both consider all samples of a microtiter plate per suspension bead array assay and thus do not require any external reference samples. We demonstrate the performance of the two MA normalization methods with data obtained from the analysis of 384 samples including both serum and plasma. Samples were randomized across 96-well sample plates, processed, and analyzed in assay plates, respectively. Using principal component analysis (PCA), we could show that plate-wise clusters found in the first two components were eliminated by multi-MA normalization as compared with other normalization methods. Furthermore, we studied the correlation profiles between random pairs of antibodies and found that both MA normalization methods substantially reduced the inflated correlation introduced by plate effects. Normalization approaches using multi-MA and MA-loess minimized batch effects arising from the analysis of several assay plates with antibody suspension bead arrays. In a simulated biomarker study, multi-MA restored associations lost due to plate effects. Our normalization approaches, which are available as R package MDimNormn, could also be useful in studies using other types of high-throughput assay data.

Influences of Normalization Method on Biomarker Discovery in Gas Chromatography-Mass Spectrometry-Based Untargeted Metabolomics: What Should Be Considered?

PubMed

Chen, Jiaqing; Zhang, Pei; Lv, Mengying; Guo, Huimin; Huang, Yin; Zhang, Zunjian; Xu, Fengguo

2017-05-16

Data reduction techniques in gas chromatography-mass spectrometry-based untargeted metabolomics has made the following workflow of data analysis more lucid. However, the normalization process still perplexes researchers, and its effects are always ignored. In order to reveal the influences of normalization method, five representative normalization methods (mass spectrometry total useful signal, median, probabilistic quotient normalization, remove unwanted variation-random, and systematic ratio normalization) were compared in three real data sets with different types. First, data reduction techniques were used to refine the original data. Then, quality control samples and relative log abundance plots were utilized to evaluate the unwanted variations and the efficiencies of normalization process. Furthermore, the potential biomarkers which were screened out by the Mann-Whitney U test, receiver operating characteristic curve analysis, random forest, and feature selection algorithm Boruta in different normalized data sets were compared. The results indicated the determination of the normalization method was difficult because the commonly accepted rules were easy to fulfill but different normalization methods had unforeseen influences on both the kind and number of potential biomarkers. Lastly, an integrated strategy for normalization method selection was recommended.

Using Non-experimental Data to Estimate Treatment Effects

PubMed Central

Stuart, Elizabeth A.; Marcus, Sue M.; Horvitz-Lennon, Marcela V.; Gibbons, Robert D.; Normand, Sharon-Lise T.

2009-01-01

While much psychiatric research is based on randomized controlled trials (RCTs), where patients are randomly assigned to treatments, sometimes RCTs are not feasible. This paper describes propensity score approaches, which are increasingly used for estimating treatment effects in non-experimental settings. The primary goal of propensity score methods is to create sets of treated and comparison subjects who look as similar as possible, in essence replicating a randomized experiment, at least with respect to observed patient characteristics. A study to estimate the metabolic effects of antipsychotic medication in a sample of Florida Medicaid beneficiaries with schizophrenia illustrates methods. PMID:20563313

Gratings and Random Reflectors for Near-Infrared PIN Diodes

NASA Technical Reports Server (NTRS)

Gunapala, Sarath; Bandara, Sumith; Liu, John; Ting, David

2007-01-01

Crossed diffraction gratings and random reflectors have been proposed as means to increase the quantum efficiencies of InGaAs/InP positive/intrinsic/ negative (PIN) diodes designed to operate as near-infrared photodetectors. The proposal is meant especially to apply to focal-plane imaging arrays of such photodetectors to be used for near-infrared imaging. A further increase in quantum efficiency near the short-wavelength limit of the near-infrared spectrum of such a photodetector array could be effected by removing the InP substrate of the array. The use of crossed diffraction gratings and random reflectors as optical devices for increasing the quantum efficiencies of quantum-well infrared photodetectors (QWIPs) was discussed in several prior NASA Tech Briefs articles. While the optical effects of crossed gratings and random reflectors as applied to PIN photodiodes would be similar to those of crossed gratings and random reflectors as applied to QWIPs, the physical mechanisms by which these optical effects would enhance efficiency differ between the PIN-photodiode and QWIP cases: In a QWIP, the multiple-quantum-well layers are typically oriented parallel to the focal plane and therefore perpendicular or nearly perpendicular to the direction of incidence of infrared light. By virtue of the applicable quantum selection rules, light polarized parallel to the focal plane (as normally incident light is) cannot excite charge carriers and, hence, cannot be detected. A pair of crossed gratings or a random reflector scatters normally or nearly normally incident light so that a significant portion of it attains a component of polarization normal to the focal plane and, hence, can excite charge carriers. A pair of crossed gratings or a random reflector on a PIN photodiode would also scatter light into directions away from the perpendicular to the focal plane. However, in this case, the reason for redirecting light away from the perpendicular is to increase the length of the optical path through the detector to increase the probability of absorption of photons and thereby increase the resulting excitation of charge carriers. A pair of crossed gratings or a random reflector according to the proposal would be fabricated as an integral part of photodetector structure on the face opposite the focal plane (see figure). In the presence of crossed gratings, light would make four passes through the device before departing. In the presence of a random reflector, a significant portion of the light would make more than four passes: After each bounce, light would be scattered at a different random angle, and would have a chance to escape only when it was reflected, relative to the normal, at an angle less than the critical angle for total internal reflection. Given the indices of refraction of the photodiode materials, this angle would be about 17 . This amounts to a very narrow cone for escape of trapped light.

Theory of Mind Training in Children with Autism: A Randomized Controlled Trial

ERIC Educational Resources Information Center

Begeer, Sander; Gevers, Carolien; Clifford, Pamela; Verhoeve, Manja; Kat, Kirstin; Hoddenbach, Elske; Boer, Frits

2011-01-01

Many children with Autism Spectrum Disorders (ASD) participate in social skills or Theory of Mind (ToM) treatments. However, few studies have shown evidence for their effectiveness. The current study used a randomized controlled design to test the effectiveness of a 16-week ToM treatment in 8-13 year old children with ASD and normal IQs (n = 40).…

Amygdala Reactivity to Emotional Faces in the Prediction of General and Medication-Specific Responses to Antidepressant Treatment in the Randomized iSPOT-D Trial.

PubMed

Williams, Leanne M; Korgaonkar, Mayuresh S; Song, Yun C; Paton, Rebecca; Eagles, Sarah; Goldstein-Piekarski, Andrea; Grieve, Stuart M; Harris, Anthony W F; Usherwood, Tim; Etkin, Amit

2015-09-01

Although the cost of poor treatment outcomes of depression is staggering, we do not yet have clinically useful methods for selecting the most effective antidepressant for each depressed person. Emotional brain activation is altered in major depressive disorder (MDD) and implicated in treatment response. Identifying which aspects of emotional brain activation are predictive of general and specific responses to antidepressants may help clinicians and patients when making treatment decisions. We examined whether amygdala activation probed by emotion stimuli is a general or differential predictor of response to three commonly prescribed antidepressants, using functional magnetic resonance imaging (fMRI). A test-retest design was used to assess patients with MDD in an academic setting as part of the International Study to Predict Optimized Treatment in Depression. A total of 80 MDD outpatients were scanned prior to treatment and 8 weeks after randomization to the selective serotonin reuptake inhibitors escitalopram and sertraline and the serotonin-norepinephrine reuptake inhibitor, venlafaxine-extended release (XR). A total of 34 matched controls were scanned at the same timepoints. We quantified the blood oxygen level-dependent signal of the amygdala during subliminal and supraliminal viewing of facial expressions of emotion. Response to treatment was defined by ⩾50% symptom improvement on the 17-item Hamilton Depression Rating Scale. Pre-treatment amygdala hypo-reactivity to subliminal happy and threat was a general predictor of treatment response, regardless of medication type (Cohen's d effect size 0.63 to 0.77; classification accuracy, 75%). Responders showed hypo-reactivity compared to controls at baseline, and an increase toward 'normalization' post-treatment. Pre-treatment amygdala reactivity to subliminal sadness was a differential moderator of non-response to venlafaxine-XR (Cohen's d effect size 1.5; classification accuracy, 81%). Non-responders to venlafaxine-XR showed pre-treatment hyper-reactivity, which progressed to hypo-reactivity rather than normalization post-treatment, and hypo-reactivity post-treatment was abnormal compared to controls. Impaired amygdala activation has not previously been highlighted in the general vs differential prediction of antidepressant outcomes. Amygdala hypo-reactivity to emotions signaling reward and threat predicts the general capacity to respond to antidepressants. Amygdala hyper-reactivity to sad emotion is involved in a specific non-response to a serotonin-norepinephrine reuptake inhibitor. The findings suggest amygdala probes may help inform the personal selection of antidepressant treatments.

Effects of Music Therapy on the Cardiovascular and Autonomic Nervous System in Stress-Induced University Students: A Randomized Controlled Trial.

PubMed

Lee, Kyoung Soon; Jeong, Hyeon Cheol; Yim, Jong Eun; Jeon, Mi Yang

2016-01-01

Stress is caused when a particular relationship between the individual and the environment emerges. Specifically, stress occurs when an individual's abilities are challenged or when one's well-being is threatened by excessive environmental demands. The aim of this study was to measure the effects of music therapy on stress in university students. Randomized controlled trial. Sixty-four students were randomly assigned to the experimental group (n = 33) or the control group (n = 31). Music therapy. Initial measurement included cardiovascular indicators (blood pressure and pulse), autonomic nervous activity (standard deviation of the normal-to-normal intervals [SDNN], normalized low frequency, normalized high frequency, low/high frequency), and subjective stress. After the first measurement, participants in both groups were exposed to a series of stressful tasks, and then a second measurement was conducted. The experimental group then listened to music for 20 minutes and the control group rested for 20 minutes. A third and final measurement was then taken. There were no significant differences between the two groups in the first or second measurement. However, after music therapy, the experimental group and the control group showed significant differences in all variables, including systolic blood pressure (p = .026), diastolic blood pressure (p = .037), pulse (p < .001), SDNN (p = .003), normalized low frequency (p < .001), normalized high frequency (p = .010), and subjective stress (p = .026). Classical music tends to relax the body and may stimulate the parasympathetic nervous system. These results suggest music therapy as an intervention for stress reduction.

Abbreviated closure for remote damage control laparotomy in extreme environments: A randomized trial of sutures versus wound clamps comparing terrestrial and weightless conditions.

PubMed

Kirkpatrick, Andrew W; McKee, Jessica Lynn; Tien, Colonel Homer; LaPorta, Anthony J; Lavell, Kit; Leslie, Tim; McBeth, Paul B; Roberts, Derek J; Ball, Chad G

2017-05-01

Far-Forward Damage Control Laparotomies (DCLs) might provide direct-compression of visceral hemorrhage, however, suturing is a limiting factor, especially for non-physicians. We thus compared abbreviated skin closures comparing skin-suture (SS) versus wound-clamp (WC), on-board a research aircraft in weightlessness (0g) and normal gravity (1g). Surgeons conducted DCLs on a surgical-simulator; onboard the hangered-aircraft (1g), or during parabolic flight (0g), randomized to either WC or SS. Ten surgeons participated. Two (40%) surgeons randomized to suture in 0g were incapacitated with motion-sickness, and none were able to close in either 1 or 0g. With WC, two completely closed in 1g as did three in 0g, despite having longer incisions (p = 0.016). Overall skin-closure with WC was significantly greater in both 1g (p = 0.016) and 0g (p = 0.008). WC was more effective in 1g and particularly 0g. Future studies should address the utility of abbreviated WC abdominal closure to facilitate potential Far-Forward DCL. ID ISRCTN/77929274. Copyright © 2017 Elsevier Inc. All rights reserved.

Cooperation evolution in random multiplicative environments

NASA Astrophysics Data System (ADS)

Yaari, G.; Solomon, S.

2010-02-01

Most real life systems have a random component: the multitude of endogenous and exogenous factors influencing them result in stochastic fluctuations of the parameters determining their dynamics. These empirical systems are in many cases subject to noise of multiplicative nature. The special properties of multiplicative noise as opposed to additive noise have been noticed for a long while. Even though apparently and formally the difference between free additive vs. multiplicative random walks consists in just a move from normal to log-normal distributions, in practice the implications are much more far reaching. While in an additive context the emergence and survival of cooperation requires special conditions (especially some level of reward, punishment, reciprocity), we find that in the multiplicative random context the emergence of cooperation is much more natural and effective. We study the various implications of this observation and its applications in various contexts.

Influence assessment in censored mixed-effects models using the multivariate Student’s-t distribution

PubMed Central

Matos, Larissa A.; Bandyopadhyay, Dipankar; Castro, Luis M.; Lachos, Victor H.

2015-01-01

In biomedical studies on HIV RNA dynamics, viral loads generate repeated measures that are often subjected to upper and lower detection limits, and hence these responses are either left- or right-censored. Linear and non-linear mixed-effects censored (LMEC/NLMEC) models are routinely used to analyse these longitudinal data, with normality assumptions for the random effects and residual errors. However, the derived inference may not be robust when these underlying normality assumptions are questionable, especially the presence of outliers and thick-tails. Motivated by this, Matos et al. (2013b) recently proposed an exact EM-type algorithm for LMEC/NLMEC models using a multivariate Student’s-t distribution, with closed-form expressions at the E-step. In this paper, we develop influence diagnostics for LMEC/NLMEC models using the multivariate Student’s-t density, based on the conditional expectation of the complete data log-likelihood. This partially eliminates the complexity associated with the approach of Cook (1977, 1986) for censored mixed-effects models. The new methodology is illustrated via an application to a longitudinal HIV dataset. In addition, a simulation study explores the accuracy of the proposed measures in detecting possible influential observations for heavy-tailed censored data under different perturbation and censoring schemes. PMID:26190871

Neither fixed nor random: weighted least squares meta-regression.

PubMed

Stanley, T D; Doucouliagos, Hristos

2017-03-01

Our study revisits and challenges two core conventional meta-regression estimators: the prevalent use of 'mixed-effects' or random-effects meta-regression analysis and the correction of standard errors that defines fixed-effects meta-regression analysis (FE-MRA). We show how and explain why an unrestricted weighted least squares MRA (WLS-MRA) estimator is superior to conventional random-effects (or mixed-effects) meta-regression when there is publication (or small-sample) bias that is as good as FE-MRA in all cases and better than fixed effects in most practical applications. Simulations and statistical theory show that WLS-MRA provides satisfactory estimates of meta-regression coefficients that are practically equivalent to mixed effects or random effects when there is no publication bias. When there is publication selection bias, WLS-MRA always has smaller bias than mixed effects or random effects. In practical applications, an unrestricted WLS meta-regression is likely to give practically equivalent or superior estimates to fixed-effects, random-effects, and mixed-effects meta-regression approaches. However, random-effects meta-regression remains viable and perhaps somewhat preferable if selection for statistical significance (publication bias) can be ruled out and when random, additive normal heterogeneity is known to directly affect the 'true' regression coefficient. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Multivariate meta-analysis: a robust approach based on the theory of U-statistic.

PubMed

Ma, Yan; Mazumdar, Madhu

2011-10-30

Meta-analysis is the methodology for combining findings from similar research studies asking the same question. When the question of interest involves multiple outcomes, multivariate meta-analysis is used to synthesize the outcomes simultaneously taking into account the correlation between the outcomes. Likelihood-based approaches, in particular restricted maximum likelihood (REML) method, are commonly utilized in this context. REML assumes a multivariate normal distribution for the random-effects model. This assumption is difficult to verify, especially for meta-analysis with small number of component studies. The use of REML also requires iterative estimation between parameters, needing moderately high computation time, especially when the dimension of outcomes is large. A multivariate method of moments (MMM) is available and is shown to perform equally well to REML. However, there is a lack of information on the performance of these two methods when the true data distribution is far from normality. In this paper, we propose a new nonparametric and non-iterative method for multivariate meta-analysis on the basis of the theory of U-statistic and compare the properties of these three procedures under both normal and skewed data through simulation studies. It is shown that the effect on estimates from REML because of non-normal data distribution is marginal and that the estimates from MMM and U-statistic-based approaches are very similar. Therefore, we conclude that for performing multivariate meta-analysis, the U-statistic estimation procedure is a viable alternative to REML and MMM. Easy implementation of all three methods are illustrated by their application to data from two published meta-analysis from the fields of hip fracture and periodontal disease. We discuss ideas for future research based on U-statistic for testing significance of between-study heterogeneity and for extending the work to meta-regression setting. Copyright © 2011 John Wiley & Sons, Ltd.

A New Approach to Extreme Value Estimation Applicable to a Wide Variety of Random Variables

NASA Technical Reports Server (NTRS)

Holland, Frederic A., Jr.

1997-01-01

Designing reliable structures requires an estimate of the maximum and minimum values (i.e., strength and load) that may be encountered in service. Yet designs based on very extreme values (to insure safety) can result in extra material usage and hence, uneconomic systems. In aerospace applications, severe over-design cannot be tolerated making it almost mandatory to design closer to the assumed limits of the design random variables. The issue then is predicting extreme values that are practical, i.e. neither too conservative or non-conservative. Obtaining design values by employing safety factors is well known to often result in overly conservative designs and. Safety factor values have historically been selected rather arbitrarily, often lacking a sound rational basis. To answer the question of how safe a design needs to be has lead design theorists to probabilistic and statistical methods. The so-called three-sigma approach is one such method and has been described as the first step in utilizing information about the data dispersion. However, this method is based on the assumption that the random variable is dispersed symmetrically about the mean and is essentially limited to normally distributed random variables. Use of this method can therefore result in unsafe or overly conservative design allowables if the common assumption of normality is incorrect.

Mechanisms for an effect of acetylcysteine on renal function after exposure to radio-graphic contrast material: study protocol.

PubMed

Sandilands, Euan A; Cameron, Sharon; Paterson, Frances; Donaldson, Sam; Briody, Lesley; Crowe, Jane; Donnelly, Julie; Thompson, Adrian; Johnston, Neil R; Mackenzie, Ivor; Uren, Neal; Goddard, Jane; Webb, David J; Megson, Ian L; Bateman, Nicholas; Eddleston, Michael

2012-02-03

Contrast-induced nephropathy is a common complication of contrast administration in patients with chronic kidney disease and diabetes. Its pathophysiology is not well understood; similarly the role of intravenous or oral acetylcysteine is unclear. Randomized controlled trials to date have been conducted without detailed knowledge of the effect of acetylcysteine on renal function. We are conducting a detailed mechanistic study of acetylcysteine on normal and impaired kidneys, both with and without contrast. This information would guide the choice of dose, route, and appropriate outcome measure for future clinical trials in patients with chronic kidney disease. We designed a 4-part study. We have set up randomised controlled cross-over studies to assess the effect of intravenous (50 mg/kg/hr for 2 hrs before contrast exposure, then 20 mg/kg/hr for 5 hrs) or oral acetylcysteine (1200 mg twice daily for 2 days, starting the day before contrast exposure) on renal function in normal and diseased kidneys, and normal kidneys exposed to contrast. We have also set up a parallel-group randomized controlled trial to assess the effect of intravenous or oral acetylcysteine on patients with chronic kidney disease stage III undergoing elective coronary angiography. The primary outcome is change in renal blood flow; secondary outcomes include change in glomerular filtration rate, tubular function, urinary proteins, and oxidative balance. Contrast-induced nephropathy represents a significant source of hospital morbidity and mortality. Over the last ten years, acetylcysteine has been administered prior to contrast to reduce the risk of contrast-induced nephropathy. Randomized controlled trials, however, have not reliably demonstrated renoprotection; a recent large randomized controlled trial assessing a dose of oral acetylcysteine selected without mechanistic insight did not reduce the incidence of contrast-induced nephropathy. Our study should reveal the mechanism of effect of acetylcysteine on renal function and identify an appropriate route for future dose response studies and in time randomized controlled trials. Clinical Trials.gov: NCT00558142; EudraCT: 2006-003509-18.

Processing Ordinality and Quantity: The Case of Developmental Dyscalculia

PubMed Central

Rubinsten, Orly; Sury, Dana

2011-01-01

In contrast to quantity processing, up to date, the nature of ordinality has received little attention from researchers despite the fact that both quantity and ordinality are embodied in numerical information. Here we ask if there are two separate core systems that lie at the foundations of numerical cognition: (1) the traditionally and well accepted numerical magnitude system but also (2) core system for representing ordinal information. We report two novel experiments of ordinal processing that explored the relation between ordinal and numerical information processing in typically developing adults and adults with developmental dyscalculia (DD). Participants made “ordered” or “non-ordered” judgments about 3 groups of dots (non-symbolic numerical stimuli; in Experiment 1) and 3 numbers (symbolic task: Experiment 2). In contrast to previous findings and arguments about quantity deficit in DD participants, when quantity and ordinality are dissociated (as in the current tasks), DD participants exhibited a normal ratio effect in the non-symbolic ordinal task. They did not show, however, the ordinality effect. Ordinality effect in DD appeared only when area and density were randomized, but only in the descending direction. In the symbolic task, the ordinality effect was modulated by ratio and direction in both groups. These findings suggest that there might be two separate cognitive representations of ordinal and quantity information and that linguistic knowledge may facilitate estimation of ordinal information. PMID:21935374

Processing ordinality and quantity: the case of developmental dyscalculia.

PubMed

Rubinsten, Orly; Sury, Dana

2011-01-01

In contrast to quantity processing, up to date, the nature of ordinality has received little attention from researchers despite the fact that both quantity and ordinality are embodied in numerical information. Here we ask if there are two separate core systems that lie at the foundations of numerical cognition: (1) the traditionally and well accepted numerical magnitude system but also (2) core system for representing ordinal information. We report two novel experiments of ordinal processing that explored the relation between ordinal and numerical information processing in typically developing adults and adults with developmental dyscalculia (DD). Participants made "ordered" or "non-ordered" judgments about 3 groups of dots (non-symbolic numerical stimuli; in Experiment 1) and 3 numbers (symbolic task: Experiment 2). In contrast to previous findings and arguments about quantity deficit in DD participants, when quantity and ordinality are dissociated (as in the current tasks), DD participants exhibited a normal ratio effect in the non-symbolic ordinal task. They did not show, however, the ordinality effect. Ordinality effect in DD appeared only when area and density were randomized, but only in the descending direction. In the symbolic task, the ordinality effect was modulated by ratio and direction in both groups. These findings suggest that there might be two separate cognitive representations of ordinal and quantity information and that linguistic knowledge may facilitate estimation of ordinal information.

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

PubMed

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.

Viscoelastic flow past mono- and bidisperse random arrays of cylinders: flow resistance, topology and normal stress distribution.

PubMed

De, S; Kuipers, J A M; Peters, E A J F; Padding, J T

2017-12-13

We investigate creeping viscoelastic fluid flow through two-dimensional porous media consisting of random arrangements of monodisperse and bidisperse cylinders, using our finite volume-immersed boundary method introduced in S. De, et al., J. Non-Newtonian Fluid Mech., 2016, 232, 67-76. The viscoelastic fluid is modeled with a FENE-P model. The simulations show an increased flow resistance with increase in flow rate, even though the bulk response of the fluid to shear flow is shear thinning. We show that if the square root of the permeability is chosen as the characteristic length scale in the determination of the dimensionless Deborah number (De), then all flow resistance curves collapse to a single master curve, irrespective of the pore geometry. Our study reveals how viscoelastic stresses and flow topologies (rotation, shear and extension) are distributed through the porous media, and how they evolve with increasing De. We correlate the local viscoelastic first normal stress differences with the local flow topology and show that the largest normal stress differences are located in shear flow dominated regions and not in extensional flow dominated regions at higher viscoelasticity. The study shows that normal stress differences in shear flow regions may play a crucial role in the increase of flow resistance for viscoelastic flow through such porous media.

Roughness Effects on Fretting Fatigue

NASA Astrophysics Data System (ADS)

Yue, Tongyan; Abdel Wahab, Magd

2017-05-01

Fretting is a small oscillatory relative motion between two normal loaded contact surfaces. It may cause fretting fatigue, fretting wear and/or fretting corrosion damage depending on various fretting couples and working conditions. Fretting fatigue usually occurs at partial slip condition, and results in catastrophic failure at the stress levels below the fatigue limit of the material. Many parameters may affect fretting behaviour, including the applied normal load and displacement, material properties, roughness of the contact surfaces, frequency, etc. Since fretting damage is undesirable due to contacting, the effect of rough contact surfaces on fretting damage has been studied by many researchers. Experimental method on this topic is usually focusing on rough surface effects by finishing treatment and random rough surface effects in order to increase fretting fatigue life. However, most of numerical models on roughness are based on random surface. This paper reviewed both experimental and numerical methodology on the rough surface effects on fretting fatigue.

A 1-Diopter Vertical Prism Induces a Decrease of Head Rotation: A Pilot Investigation.

PubMed

Matheron, Eric; Zandi, Ava; Wang, Danping; Kapoula, Zoï

2016-01-01

Clinical studies in non-specific chronic arthralgia and back pain seem to indicate an association between vertical heterophoria (VH - latent vertical retinal misalignment) and asymmetrical head rotation. Such clinical observations suggest a link between VH and head rotation, but this was never tested. The purpose of this study was to simulate a VH in healthy subjects and examine its influence on the amplitude of active head rotation during 3D motion capture in upright stance. Subjects were asked to rotate their head three times from the straight ahead position and then to the right, back to straight ahead, to the left, and back to the straight ahead again. Three randomized conditions were run: normal viewing, with a 1-diopter prism base down on the dominant eye, or the non-dominant eye. The most important finding is that the experimental VH whichever the eye with the prism induces a significant decrease in the mean angle of head rotation compared to the normal viewing condition. This decrease was significant for rotation to the left. We suggest that the prism-induced VH modifies the reference posture and thereby affects head rotation; further studies are needed to confirm this effect and to extend to other types of dynamic activities.

Loss of Sexual Reproduction and Dwarfing in a Small Metazoan

PubMed Central

Stelzer, Claus-Peter; Schmidt, Johanna; Wiedlroither, Anneliese; Riss, Simone

2010-01-01

Background Asexuality has major theoretical advantages over sexual reproduction, yet newly formed asexual lineages rarely endure. The success, or failure, of such lineages is affected by their mechanism of origin, because it determines their initial genetic makeup and variability. Most previously described mechanisms imply that asexual lineages are randomly frozen subsamples of a sexual population. Methodology/Principal Findings We found that transitions to obligate parthenogenesis (OP) in the rotifer Brachionus calyciflorus, a small freshwater invertebrate which normally reproduces by cyclical parthenogenesis, were controlled by a simple Mendelian inheritance. Pedigree analysis suggested that obligate parthenogens were homozygous for a recessive allele, which caused inability to respond to the chemical signals that normally induce sexual reproduction in this species. Alternative mechanisms, such as ploidy changes, could be ruled out on the basis of flow cytometric measurements and genetic marker analysis. Interestingly, obligate parthenogens were also dwarfs (approximately 50% smaller than cyclical parthenogens), indicating pleiotropy or linkage with genes that strongly affect body size. We found no adverse effects of OP on survival or fecundity. Conclusions/Significance This mechanism of inheritance implies that genes causing OP may evolve within sexual populations and remain undetected in the heterozygous state long before they get frequent enough to actually cause a transition to asexual reproduction. In this process, genetic variation at other loci might become linked to OP genes, leading to non-random associations between asexuality and other phenotypic traits. PMID:20862222

Dexmedetomidine in Attenuation of Haemodynamic Response and Dose Sparing Effect on Opioid and Anaesthetic Agents in Patients undergoing Laparoscopic Cholecystectomy- A Randomized Study

PubMed Central

Bhagat, Nandlal; Karim, Habib Md Reazaul; Hajong, Ranendra; Bhattacharyya, Prithwis; Singh, Manorama

2016-01-01

Introduction Perioperative procedures are stressful and lead to haemodynamic instability with potentially devastating consequences. Dexmedetomidine is found to have many of the desired characteristics that are required in perioperative period. Aim To evaluate the ability of pre and intraoperative dexmedetomidine to attenuate stress induced haemodynamic responses, quantifying the anaesthetic agents sparing as well as its cost-effectiveness in patients undergoing laparoscopic cholecystectomy. Materials and Methods The present single blind randomized study was conducted with 120 ASA I and II consented patients who underwent laparoscopic cholecystectomy. Patients were randomly divided into 2 groups (i.e., group D and group N). Prior to induction, group D received 1 μg/kg of Dexmedetomidine and group N received Normal saline infusion over 20 minutes. Group D also received maintenance Dexmedetomidine intraoperatively. Bispectral index and minimum alveolar concentration monitoring was done in both the groups. Haemodynamic parameters were noted till 100 minutes post laryngoscopy. Opioid and anaesthetic agent consumptions were also noted and cost analysis was done. Medcalc–Version 12.5.0.0 software was used for statistics and p <0.05 was considered significant. Results Dexmedetomidine attenuated the stress induced haemodynamics responses and produced stable, relatively non fluctuating haemodynamics throughout. The Minimum Alveolar Concentration (MAC) requirement and the consumptions of Fentanyl and Isoflurane were significantly less in the Dexmedetomidine group (p<0.0001). However, despite anaesthetic dose sparing effect the anaesthetic technique was not cost-effective. Conclusion Dexmedetomidine is effective in attenuating haemodynamic responses in laparoscopic surgery and having dose sparing effect on Fentanyl, Propofol and Isoflurane. However, overall this technique is not cost-effective. PMID:28050479

What affects response rates in primary healthcare-based programmes? An analysis of individual and unit-related factors associated with increased odds of non-response based on HCV screening in the general population in Poland

PubMed Central

Parda, Natalia; Stępień, Małgorzata; Zakrzewska, Karolina; Madaliński, Kazimierz; Kołakowska, Agnieszka; Godzik, Paulina; Rosińska, Magdalena

2016-01-01

Objectives Response rate in public health programmes may be a limiting factor. It is important to first consider their delivery and acceptability for the target. This study aimed at determining individual and unit-related factors associated with increased odds of non-response based on hepatitis C virus screening in primary healthcare. Design Primary healthcare units (PHCUs) were extracted from the Register of Health Care Centres. Each of the PHCUs was to enrol adult patients selected on a random basis. Data on the recruitment of PHCUs and patients were analysed. Multilevel modelling was applied to investigate individual and unit-related factors associated with non-response. Multilevel logistic model was developed with fixed effects and only a random intercept for the unit. Preliminary analysis included a random effect for unit and each of the individual or PHCU covariates separately. For each of the PHCU covariates, we applied a two-level model with individual covariates, unit random effect and a single fixed effect of this unit covariate. Setting This study was conducted in primary care units in selected provinces in Poland. Participants A total of 242 PHCUs and 24 480 adults were invited. Of them, 44 PHCUs and 20 939 patients agreed to participate. Both PHCUs and patients were randomly selected. Results Data on 44 PHCUs and 24 480 patients were analysed. PHCU-level factors and recruitment strategies were important predictors of non-response. Unit random effect was significant in all models. Larger and private units reported higher non-response rates, while for those with a history of running public health programmes the odds of non-response was lower. Proactive recruitment, more working hours devoted to the project and patient resulted in higher acceptance of the project. Higher number of personnel had no such effect. Conclusions Prior to the implementation of public health programme, several factors that could hinder its execution should be addressed. PMID:27927665

What affects response rates in primary healthcare-based programmes? An analysis of individual and unit-related factors associated with increased odds of non-response based on HCV screening in the general population in Poland.

PubMed

Parda, Natalia; Stępień, Małgorzata; Zakrzewska, Karolina; Madaliński, Kazimierz; Kołakowska, Agnieszka; Godzik, Paulina; Rosińska, Magdalena

2016-12-07

Response rate in public health programmes may be a limiting factor. It is important to first consider their delivery and acceptability for the target. This study aimed at determining individual and unit-related factors associated with increased odds of non-response based on hepatitis C virus screening in primary healthcare. Primary healthcare units (PHCUs) were extracted from the Register of Health Care Centres. Each of the PHCUs was to enrol adult patients selected on a random basis. Data on the recruitment of PHCUs and patients were analysed. Multilevel modelling was applied to investigate individual and unit-related factors associated with non-response. Multilevel logistic model was developed with fixed effects and only a random intercept for the unit. Preliminary analysis included a random effect for unit and each of the individual or PHCU covariates separately. For each of the PHCU covariates, we applied a two-level model with individual covariates, unit random effect and a single fixed effect of this unit covariate. This study was conducted in primary care units in selected provinces in Poland. A total of 242 PHCUs and 24 480 adults were invited. Of them, 44 PHCUs and 20 939 patients agreed to participate. Both PHCUs and patients were randomly selected. Data on 44 PHCUs and 24 480 patients were analysed. PHCU-level factors and recruitment strategies were important predictors of non-response. Unit random effect was significant in all models. Larger and private units reported higher non-response rates, while for those with a history of running public health programmes the odds of non-response was lower. Proactive recruitment, more working hours devoted to the project and patient resulted in higher acceptance of the project. Higher number of personnel had no such effect. Prior to the implementation of public health programme, several factors that could hinder its execution should be addressed. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

A Mixed Effects Randomized Item Response Model

ERIC Educational Resources Information Center

Fox, J.-P.; Wyrick, Cheryl

2008-01-01

The randomized response technique ensures that individual item responses, denoted as true item responses, are randomized before observing them and so-called randomized item responses are observed. A relationship is specified between randomized item response data and true item response data. True item response data are modeled with a (non)linear…

Refining insulin concentrations in culture medium containing growth factors BMP15 and GDF9: An in vitro study of the effects on follicle development of goats.

PubMed

Dipaz-Berrocal, D J; Sá, N A R; Guerreiro, D D; Celestino, J J H; Leiva-Revilla, J; Alves, B G; Alves, K A; Santos, R R; Cibin, F W S; Rodrigues, A P R; Figueiredo, J R

2017-10-01

The aim of the present study was to investigate the influence of two insulin concentrations (10ng/mL and 10μg/mL) combined or in the absence of BMP15 and/or GDF9, on the in vitro survival and development of preantral follicles of goat ovarian tissue. Ovarian slices from the same goat ovary pair were randomly assigned to a non-cultured control treatment or to be in vitro cultured for 1 or 7days in α-MEM containing 10ng/mL (Low) or 10μg/mL (High) of insulin in the absence or presence of BMP15 and/or GDF9. With the low insulin treatment, there was a greater percentage of normal follicles than with the high insulin treatment. The addition of BMP15 alone or in association with GDF9 to the medium containing low insulin resulted in a lesser percentage of normal follicles (P<0.05). The addition of BMP15 and GDF9 separately or in combination with the high insulin concentration enhanced the percentage of normal follicles. On day 7 of culture, the use of medium containing low insulin alone or high insulin supplemented with BMP15 and BMP15+GDF9 resulted in a greater percentage of secondary follicles than the non-cultured control, although follicles cultured with low insulin were smaller than those from the control group and had greater rates of oxidative stress. In conclusion, in the presence of physiological concentrations of insulin (10ng/mL), medium supplementation with GDF9 and BMP15 alone or in combination is unnecessary for normal follicle development in vitro. Copyright © 2017 Elsevier B.V. All rights reserved.

How does aging affect the types of error made in a visual short-term memory ‘object-recall’ task?

PubMed Central

Sapkota, Raju P.; van der Linde, Ian; Pardhan, Shahina

2015-01-01

This study examines how normal aging affects the occurrence of different types of incorrect responses in a visual short-term memory (VSTM) object-recall task. Seventeen young (Mean = 23.3 years, SD = 3.76), and 17 normally aging older (Mean = 66.5 years, SD = 6.30) adults participated. Memory stimuli comprised two or four real world objects (the memory load) presented sequentially, each for 650 ms, at random locations on a computer screen. After a 1000 ms retention interval, a test display was presented, comprising an empty box at one of the previously presented two or four memory stimulus locations. Participants were asked to report the name of the object presented at the cued location. Errors rates wherein participants reported the names of objects that had been presented in the memory display but not at the cued location (non-target errors) vs. objects that had not been presented at all in the memory display (non-memory errors) were compared. Significant effects of aging, memory load and target recency on error type and absolute error rates were found. Non-target error rate was higher than non-memory error rate in both age groups, indicating that VSTM may have been more often than not populated with partial traces of previously presented items. At high memory load, non-memory error rate was higher in young participants (compared to older participants) when the memory target had been presented at the earliest temporal position. However, non-target error rates exhibited a reversed trend, i.e., greater error rates were found in older participants when the memory target had been presented at the two most recent temporal positions. Data are interpreted in terms of proactive interference (earlier examined non-target items interfering with more recent items), false memories (non-memory items which have a categorical relationship to presented items, interfering with memory targets), slot and flexible resource models, and spatial coding deficits. PMID:25653615

How does aging affect the types of error made in a visual short-term memory 'object-recall' task?

PubMed

Sapkota, Raju P; van der Linde, Ian; Pardhan, Shahina

2014-01-01

This study examines how normal aging affects the occurrence of different types of incorrect responses in a visual short-term memory (VSTM) object-recall task. Seventeen young (Mean = 23.3 years, SD = 3.76), and 17 normally aging older (Mean = 66.5 years, SD = 6.30) adults participated. Memory stimuli comprised two or four real world objects (the memory load) presented sequentially, each for 650 ms, at random locations on a computer screen. After a 1000 ms retention interval, a test display was presented, comprising an empty box at one of the previously presented two or four memory stimulus locations. Participants were asked to report the name of the object presented at the cued location. Errors rates wherein participants reported the names of objects that had been presented in the memory display but not at the cued location (non-target errors) vs. objects that had not been presented at all in the memory display (non-memory errors) were compared. Significant effects of aging, memory load and target recency on error type and absolute error rates were found. Non-target error rate was higher than non-memory error rate in both age groups, indicating that VSTM may have been more often than not populated with partial traces of previously presented items. At high memory load, non-memory error rate was higher in young participants (compared to older participants) when the memory target had been presented at the earliest temporal position. However, non-target error rates exhibited a reversed trend, i.e., greater error rates were found in older participants when the memory target had been presented at the two most recent temporal positions. Data are interpreted in terms of proactive interference (earlier examined non-target items interfering with more recent items), false memories (non-memory items which have a categorical relationship to presented items, interfering with memory targets), slot and flexible resource models, and spatial coding deficits.

Analgesic effects of treatments for non-specific low back pain: a meta-analysis of placebo-controlled randomized trials.

PubMed

Machado, L A C; Kamper, S J; Herbert, R D; Maher, C G; McAuley, J H

2009-05-01

Estimates of treatment effects reported in placebo-controlled randomized trials are less subject to bias than those estimates provided by other study designs. The objective of this meta-analysis was to estimate the analgesic effects of treatments for non-specific low back pain reported in placebo-controlled randomized trials. Medline, Embase, Cinahl, PsychInfo and Cochrane Central Register of Controlled Trials databases were searched for eligible trials from earliest records to November 2006. Continuous pain outcomes were converted to a common 0-100 scale and pooled using a random effects model. A total of 76 trials reporting on 34 treatments were included. Fifty percent of the investigated treatments had statistically significant effects, but for most the effects were small or moderate: 47% had point estimates of effects of <10 points on the 100-point scale, 38% had point estimates from 10 to 20 points and 15% had point estimates of >20 points. Treatments reported to have large effects (>20 points) had been investigated only in a single trial. This meta-analysis revealed that the analgesic effects of many treatments for non-specific low back pain are small and that they do not differ in populations with acute or chronic symptoms.

The great importance of normalization of LC-MS data for highly-accurate non-targeted metabolomics.

PubMed

Mizuno, Hajime; Ueda, Kazuki; Kobayashi, Yuta; Tsuyama, Naohiro; Todoroki, Kenichiro; Min, Jun Zhe; Toyo'oka, Toshimasa

2017-01-01

The non-targeted metabolomics analysis of biological samples is very important to understand biological functions and diseases. LC combined with electrospray ionization-based MS has been a powerful tool and widely used for metabolomic analyses. However, the ionization efficiency of electrospray ionization fluctuates for various unexpected reasons such as matrix effects and intraday variations of the instrument performances. To remove these fluctuations, normalization methods have been developed. Such techniques include increasing the sensitivity, separating co-eluting components and normalizing the ionization efficiencies. Normalization techniques allow simultaneously correcting of the ionization efficiencies of the detected metabolite peaks and achieving quantitative non-targeted metabolomics. In this review paper, we focused on these normalization methods for non-targeted metabolomics by LC-MS. Copyright © 2016 John Wiley & Sons, Ltd.

A randomized, double crossover study to investigate the influence of saline infusion on sleep apnea severity in men.

PubMed

Yadollahi, Azadeh; Gabriel, Joseph M; White, Laura H; Taranto Montemurro, Luigi; Kasai, Takatoshi; Bradley, T Douglas

2014-10-01

Obstructive sleep apnea (OSA) is commoner in patients with fluid-retaining states than in those without fluid retention, in men than in women, and worsens with aging. In men, OSA severity is related to the amount of fluid shifting out of the legs overnight, but a cause-effect relationship is not established. Our objective was to test the hypothesis that mimicking fluid overload during sleep would increase severity of OSA more in older (≥ 40 years) than in younger men (< 40 years). Randomized, single-blind, double crossover study. Research sleep laboratory. Seven older and 10 younger men with non-severe or no sleep apnea, matched for body mass index. During the control arm, normal saline was infused to keep the vein open. During intervention, subjects received an intravenous bolus of normal saline (22 mL/kg body weight) after sleep onset while they were wearing compression stockings to prevent fluid accumulation in the legs. Compared to younger men, infusion of similar amounts of saline in older men caused a greater increase in neck circumference (P < 0.05) and in the AHI (32.2 ± 22.1 vs. 2.2 ± 7.1, P = 0.002). Older men are more susceptible to the adverse effects of intravenous fluid loading on obstructive sleep apnea severity than younger men. This may be due to age-related differences in the amount of fluid accumulating in the neck or upper airway collapsibility in response to intravenous fluid loading. These possibilities remain to be tested in future studies. © 2014 Associated Professional Sleep Societies, LLC.

The Anesthetic Efficacy of Articaine and Lidocaine in Equivalent Doses as Buccal and Non-Palatal Infiltration for Maxillary Molar Extraction: A Randomized, Double-Blinded, Placebo-Controlled Clinical Trial.

PubMed

Majid, Omer Waleed; Ahmed, Aws Mahmood

2018-04-01

The purpose of the present study was to evaluate the anesthetic adequacy of 4% articaine 1.8 mL versus 2% lidocaine 3.6 mL without palatal injection compared with the standard technique for the extraction of maxillary molar teeth. This randomized, double-blinded, placebo-controlled clinical trial included patients requiring extraction of 1 maxillary molar under local anesthesia. Patients were randomly distributed into 1 of 3 groups: group A received 4% articaine 1.8 mL as a buccal injection and 0.2 mL as a palatal injection, group B received 4% articaine 1.8 mL plus normal saline 0.2 mL as a palatal injection, and group C received 2% lidocaine 3.6 mL plus normal saline 0.2 mL as a palatal injection. Pain was measured during injection, 8 minutes afterward, and during extraction using a visual analog scale. Initial palatal anesthesia and patients' satisfaction were measured using a 5-score verbal rating scale. Statistical analyses included descriptive statistics, analysis of variance, and Pearson χ 2 test. Differences with a P value less than .05 were considered significant. Eighty-four patients were included in the study. The average pain of injection was comparable among all study groups (P = .933). Pain during extraction in the articaine group was significantly less than that experienced in the placebo groups (P < .001), although the differences between placebo groups were insignificant. Satisfaction scores were significantly higher in the articaine group compared with the placebo groups (P < .001), with comparable results between placebo groups. Although the anesthetic effects of single placebo-controlled buccal injections of 4% articaine and 2% lidocaine were comparable, the level of anesthetic adequacy was statistically less than that achieved by 4% articaine given by the standard technique. These results do not justify the buccal and non-palatal infiltration of articaine or lidocaine as an effective alternative to the standard technique in the extraction of maxillary molar teeth. Copyright © 2017 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

Study design and data analysis considerations for the discovery of prognostic molecular biomarkers: a case study of progression free survival in advanced serous ovarian cancer.

PubMed

Qin, Li-Xuan; Levine, Douglas A

2016-06-10

Accurate discovery of molecular biomarkers that are prognostic of a clinical outcome is an important yet challenging task, partly due to the combination of the typically weak genomic signal for a clinical outcome and the frequently strong noise due to microarray handling effects. Effective strategies to resolve this challenge are in dire need. We set out to assess the use of careful study design and data normalization for the discovery of prognostic molecular biomarkers. Taking progression free survival in advanced serous ovarian cancer as an example, we conducted empirical analysis on two sets of microRNA arrays for the same set of tumor samples: arrays in one set were collected using careful study design (that is, uniform handling and randomized array-to-sample assignment) and arrays in the other set were not. We found that (1) handling effects can confound the clinical outcome under study as a result of chance even with randomization, (2) the level of confounding handling effects can be reduced by data normalization, and (3) good study design cannot be replaced by post-hoc normalization. In addition, we provided a practical approach to define positive and negative control markers for detecting handling effects and assessing the performance of a normalization method. Our work showcased the difficulty of finding prognostic biomarkers for a clinical outcome of weak genomic signals, illustrated the benefits of careful study design and data normalization, and provided a practical approach to identify handling effects and select a beneficial normalization method. Our work calls for careful study design and data analysis for the discovery of robust and translatable molecular biomarkers.

What's normal? Influencing women's perceptions of normal genitalia: an experiment involving exposure to modified and nonmodified images.

PubMed

Moran, C; Lee, C

2014-05-01

Examine women's perceptions of what is 'normal' and 'desirable' in female genital appearance. Experiment with random allocation across three conditions. Community. A total of 97 women aged 18-30 years. Women were randomly assigned to view a series of images of (1) surgically modified vulvas or (2) nonmodified vulvas, or (3) no images. They then viewed and rated ten target images of surgically modified vulvas and ten of unmodified vulvas. Women used a four-point Likert scale ('strongly agree' to 'strongly disagree'), to rate each target image for 'looks normal' and 'represents society's ideal'. For each woman, we created two summary scores that represented the extent to which she rated the unmodified vulvas as more 'normal' and more 'society's ideal' than the modified vulvas. For ratings of 'normality,' there was a significant effect for condition (F2,94  = 2.75 P = 0.007, radj2 = 0.082): women who had first viewed the modified images rated the modified target vulvas as more normal than the nonmodified vulvas, significantly different from the control group, who rated them as less normal. For ratings of 'society's ideal', there was again a significant effect for condition (F2,92  = 7.72, P < 0.001, radj2 = 0.125); all three groups rated modified target vulvas as more like society's ideal than the nonmodified target vulvas, with the effect significantly strongest for the women who had viewed the modified images. Exposure to images of modified vulvas may change women's perceptions of what is normal and desirable. This may explain why some healthy women seek labiaplasty. © 2013 Royal College of Obstetricians and Gynaecologists.

Clinical investigation of the effect of topical anesthesia on intraocular pressure

PubMed Central

Almubrad, Turki M; Ogbuehi, Kelechi C

2007-01-01

Background/Aims: Contact tonometry is generally considered more accurate than non-contact tonometry in the assessment of intraocular pressure (IOP). This study was designed to investigate the effect of ocular anesthesia, a pre-requisite for contact tonometry, on the IOP in a sample of visually normal subjects. Method: In a random sample of 120 young visually normal subjects (divided equally among three groups), the Topcon CT80 non-contact tonometer was used to measure IOP before, at the second minute and at the fifth minute following instillation of one drop of one of three eyedrops – carboxymethylcellulose sodium 0.5% (control), oxybuprocaine hydrochloride 0.4% and proparacaine hydrochloride 0.5%. Results: The IOP measured before instilling the ophthalmic drops did not vary significantly among the three groups of subjects (p > 0.05). In the control group, the average IOP of 15.1 ± 2.6 mmHg did not vary significantly (p > 0.05) 2 minutes and 5 minutes following instillation of one drop of Carboxymethylcellulose sodium. There were statistically significant reductions of IOP 2 minutes (p < 0.01) and 5 minutes (p < 0.001) after the instillation of one drop of oxybuprocaine hydrochloride. One drop of proparacaine hydrochloride caused significant reductions in the average IOP after 2 minutes (p < 0.001) and after 5 minutes (p < 0.001). Conclusions: One drop of topical proparacaine or oxybuprocaine may cause a small but a statistically significant reduction in IOP which could lead to lower IOP readings. PMID:19668485

Clinical investigation of the effect of topical anesthesia on intraocular pressure.

PubMed

Almubrad, Turki M; Ogbuehi, Kelechi C

2007-09-01

Contact tonometry is generally considered more accurate than non-contact tonometry in the assessment of intraocular pressure (IOP). This study was designed to investigate the effect of ocular anesthesia, a pre-requisite for contact tonometry, on the IOP in a sample of visually normal subjects. In a random sample of 120 young visually normal subjects (divided equally among three groups), the Topcon CT80 non-contact tonometer was used to measure IOP before, at the second minute and at the fifth minute following instillation of one drop of one of three eyedrops - carboxymethylcellulose sodium 0.5% (control), oxybuprocaine hydrochloride 0.4% and proparacaine hydrochloride 0.5%. The IOP measured before instilling the ophthalmic drops did not vary significantly among the three groups of subjects (p > 0.05). In the control group, the average IOP of 15.1 +/- 2.6 mmHg did not vary significantly (p > 0.05) 2 minutes and 5 minutes following instillation of one drop of Carboxymethylcellulose sodium. There were statistically significant reductions of IOP 2 minutes (p < 0.01) and 5 minutes (p < 0.001) after the instillation of one drop of oxybuprocaine hydrochloride. One drop of proparacaine hydrochloride caused significant reductions in the average IOP after 2 minutes (p < 0.001) and after 5 minutes (p < 0.001). One drop of topical proparacaine or oxybuprocaine may cause a small but a statistically significant reduction in IOP which could lead to lower IOP readings.

Effect of super dosing of phytase on growth performance, ileal digestibility and bone characteristics in broilers fed corn-soya-based diets.

PubMed

Manobhavan, M; Elangovan, A V; Sridhar, M; Shet, D; Ajith, S; Pal, D T; Gowda, N K S

2016-02-01

A feeding trial was designed to assess the effect of super dosing of phytase in corn-soya-based diets of broiler chicken. One hundred and sixty-eight day-old broilers were selected and randomly allocated to four dietary treatment groups, with 6 replicates having 7 chicks per treatment group. Two-phased diets were used. The starter and finisher diet was fed from 0 to 3 weeks and 4 to 5 weeks of age respectively. The dietary treatments were consisted of normal phosphorus (NP) group without any phytase enzyme (4.5 g/kg available/non-phytin phosphorus (P) during starter and 4.0 g/kg during finisher phase), three low-phosphorus (LP) groups (3.2 g/kg available/non-phytin P during starter and 2.8 g/kg during finisher phase) supplemented with phytase at 500, 2500, 5000 FTU/kg diet, respectively, to full fill their phosphorus requirements. The results showed that super doses of phytase (at 2500 FTU and 5000 FTU/kg) on low-phosphorus diet improved feed intake, body weight gain, ileal digestibility (serine, aspartic acid, calcium, phosphorus), blood P levels and bone minerals such as calcium (Ca), P, magnesium (Mg) and zinc (Zn) content. It could be concluded that super doses of phytase in low-phosphorus diet were beneficial than the normal standard dose (at 500 FTU/kg) of phytase in diet of broiler chicken. Journal of Animal Physiology and Animal Nutrition © 2015 Blackwell Verlag GmbH.

Smoking cessation and reduction in schizophrenia (SCARIS) with e-cigarette: study protocol for a randomized control trial.

PubMed

Caponnetto, Pasquale; Polosa, Riccardo; Auditore, Roberta; Minutolo, Giuseppe; Signorelli, Maria; Maglia, Marilena; Alamo, Angela; Palermo, Filippo; Aguglia, Eugenio

2014-03-22

It is well established in studies across several countries that tobacco smoking is more prevalent among schizophrenic patients than the general population. Electronic cigarettes are becoming increasingly popular with smokers worldwide. To date there are no large randomized trials of electronic cigarettes in schizophrenic smokers. A well-designed trial is needed to compare efficacy and safety of these products in this special population. We have designed a randomized controlled trial investigating the efficacy and safety of electronic cigarette. The trial will take the form of a prospective 12-month randomized clinical study to evaluate smoking reduction, smoking abstinence and adverse events in schizophrenic smokers not intending to quit. We will also monitor quality of life, neurocognitive functioning and measure participants' perception and satisfaction of the product. A ≥50% reduction in the number of cigarettes/day from baseline, will be calculated at each study visit ("reducers"). Abstinence from smoking will be calculated at each study visit ("quitters"). Smokers who leave the study protocol before its completion and will carry out the Early Termination Visit or who will not satisfy the criteria of "reducers" and "quitters" will be defined "non responders". The differences of continuous variables between the three groups will be evaluated with the Kruskal-Wallis Test, followed by the Dunn multiple comparison test. The differences between the three groups for normally distributed data will be evaluated with ANOVA test one way, followed by the Newman-Keuls multiple comparison test. The normality of the distribution will be evaluated with the Kolmogorov-Smirnov test. Any correlations between the variables under evaluation will be assessed by Spearman r correlation. To compare qualitative data will be used the Chi-square test. The main strengths of the SCARIS study are the following: it's the first large RCT on schizophrenic patient, involving in and outpatient, evaluating the effect of a three-arm study design, and a long term of follow-up (52-weeks).The goal is to propose an effective intervention to reduce the risk of tobacco smoking, as a complementary tool to treat tobacco addiction in schizophrenia. ClinicalTrials.gov, NCT01979796.

Efficacy and safety of mipomersen in treatment of dyslipidemia: a meta-analysis of randomized controlled trials.

PubMed

Panta, Raju; Dahal, Khagendra; Kunwar, Sumit

2015-01-01

Low-density lipoprotein cholesterol (LDL-C) is the primary target of lipid-lowering therapy in people at risk for cardiovascular diseases. Mipomersen inhibits apolipoprotein B-100 (apoB) synthesis and causes reduction in LDL-C by reducing apoB. We aimed to perform a meta-analysis of all published randomized controlled trials comparing safety and efficacy of mipomersen with placebo in adults with dyslipidemia. We searched PUBMED, CENTRAL, and EMBASE from inception through March 2014 and used random-effects model to compute the effect size. We identified 8 randomized controlled trials (n = 462). Mipomersen compared with placebo significantly reduced LDL-C by 32.37% (95% confidence interval, 25.55-39.18; P < .00001), total cholesterol by 24.18% (18.54-29.83; P < .00001), very low-density lipoprotein cholesterol by 21.59% (9.16-34.02; P = .0007), non-high-density lipoprotein cholesterol (HDL-C) by 30.83% (23.92-37.74; P < .00001), and triglycerides by 36.26% (22-50.54; P < .00001). It also significantly reduced apoB, lipoprotein(a), and apolipoprotein A1. However, mipomersen did not significantly change HDL-C levels. In safety analysis, mipomersen compared with placebo increased the risks of injection-site reaction (risk ratio, 2.05; 95% confidence interval, 1.39-3.04; P = .0003), flu-like symptoms (1.63; 1.22-2.17; P = .0008), alanine aminotransferase ≥3X upper limit of normal (4.44; 1.67-11.86; P = .003), and hepatic steatosis (3.85, 1.39-10.67; P = .01). The risks of alanine aminotransferase ≥10X upper limit of normal did not reach statistical significance (1.57; 0.32-7.6, P = .58). Mipomersen resulted in a significant improvement in lipid parameters except for HDL-C and increased the risks of injection-site reactions, flu-like symptoms, and hepatic steatosis compared with placebo. Copyright © 2015 National Lipid Association. Published by Elsevier Inc. All rights reserved.

Effects of sugar-free chewing gum sweetened with xylitol or maltitol on the development of gingivitis and plaque: a randomized clinical trial.

PubMed

Keukenmeester, R S; Slot, D E; Rosema, N A M; Van Loveren, C; Van der Weijden, G A

2014-11-01

The objective of this study was to test the effect of sugar-free chewing gum sweetened with xylitol or maltitol compared to the use of a gum base or no gum on gingivitis and plaque scores under both brushing and non-brushing circumstances. The design of the study was a four-group, double-blinded, randomized controlled study with a 3-week duration. In each group, the participants did not brush the teeth in the lower jaw designated to develop experimental gingivitis, while maintaining normal oral hygiene procedures in the upper jaw. After professional dental prophylaxis, the participants were allocated into one of four groups (xylitol, maltitol, gum base or no gum). Chewing gum was used five times a day for 10 min. 220 participants completed the study and provided evaluable data. The increase in bleeding on marginal probing (BOMP) and plaque scores (PS) in the non-brushed (lower) jaw with experimental gingivitis was significant in all groups (P < 0.001). As compared to the gum base, the increase in BOMP in the xylitol and maltitol group was significantly lower. In the brushed upper jaw, no significant changes for BOMP were observed from the baseline to the end point of the study, and there were no significant differences in BOMP and PS between the groups. In circumstances where regular brushing is performed, no effect of chewing gum was observed on bleeding and plaque scores. In the absence of brushing, chewing xylitol or maltitol gum provided a significant inhibitory effect on gingivitis scores compared to chewing gum base. The difference when compared to the group not using gum was not significant. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

The Effects of Non-Normality on Type III Error for Comparing Independent Means

ERIC Educational Resources Information Center

Mendes, Mehmet

2007-01-01

The major objective of this study was to investigate the effects of non-normality on Type III error rates for ANOVA F its three commonly recommended parametric counterparts namely Welch, Brown-Forsythe, and Alexander-Govern test. Therefore these tests were compared in terms of Type III error rates across the variety of population distributions,…

Effects of nandrolone decanoate on time to consolidation of bone defects resulting from osteotomy for tibial tuberosity advancement.

PubMed

Marques, Danilo R C; Marques, Danilo; Ibanez, Jose F; Freitas, Itallo B; Hespanha, Ana C; Monteiro, Juliana F; Eggert, Mayara; Becker, Amanda

2017-09-12

Experimental study. The aim of this study was to evaluate the effect of nandrolone decanoate (ND) on the time taken for bone consolidation in dogs undergoing tibial tuberosity advancement surgery (TTA). Seventeen dogs that underwent TTA surgery were randomly divided into two groups: group C (TTA; 9 stifles), and group TTA+ND (TTA and systemic administration of ND; 8 stifles). Three observers (two radiologists and an orthopaedic surgeon), assessed bone consolidation by visual inspection of serial radiographs at intervals of 21 days following surgery. There were no differences in median weight and age between groups, nor between the medians of the variables right and left stifle. Only weight and age values were normally distributed. The other variables, right and left stifle and time to consolidation, showed non-normal distribution. Meniscal injury was present in all animals in group C and all animals in group TTA+ND. There was a significant difference between time to consolidation in groups C and TTA+ND (p <0.05). One animal in the group TTA+ND showed increased libido. Kappa agreement among observers on radiographs was 0.87. Administration of ND reduces time to bone consolidation in dogs undergoing TTA.

Mean first-passage times of non-Markovian random walkers in confinement.

PubMed

Guérin, T; Levernier, N; Bénichou, O; Voituriez, R

2016-06-16

The first-passage time, defined as the time a random walker takes to reach a target point in a confining domain, is a key quantity in the theory of stochastic processes. Its importance comes from its crucial role in quantifying the efficiency of processes as varied as diffusion-limited reactions, target search processes or the spread of diseases. Most methods of determining the properties of first-passage time in confined domains have been limited to Markovian (memoryless) processes. However, as soon as the random walker interacts with its environment, memory effects cannot be neglected: that is, the future motion of the random walker does not depend only on its current position, but also on its past trajectory. Examples of non-Markovian dynamics include single-file diffusion in narrow channels, or the motion of a tracer particle either attached to a polymeric chain or diffusing in simple or complex fluids such as nematics, dense soft colloids or viscoelastic solutions. Here we introduce an analytical approach to calculate, in the limit of a large confining volume, the mean first-passage time of a Gaussian non-Markovian random walker to a target. The non-Markovian features of the dynamics are encompassed by determining the statistical properties of the fictitious trajectory that the random walker would follow after the first-passage event takes place, which are shown to govern the first-passage time kinetics. This analysis is applicable to a broad range of stochastic processes, which may be correlated at long times. Our theoretical predictions are confirmed by numerical simulations for several examples of non-Markovian processes, including the case of fractional Brownian motion in one and higher dimensions. These results reveal, on the basis of Gaussian processes, the importance of memory effects in first-passage statistics of non-Markovian random walkers in confinement.

Mean first-passage times of non-Markovian random walkers in confinement

NASA Astrophysics Data System (ADS)

Guérin, T.; Levernier, N.; Bénichou, O.; Voituriez, R.

2016-06-01

The first-passage time, defined as the time a random walker takes to reach a target point in a confining domain, is a key quantity in the theory of stochastic processes. Its importance comes from its crucial role in quantifying the efficiency of processes as varied as diffusion-limited reactions, target search processes or the spread of diseases. Most methods of determining the properties of first-passage time in confined domains have been limited to Markovian (memoryless) processes. However, as soon as the random walker interacts with its environment, memory effects cannot be neglected: that is, the future motion of the random walker does not depend only on its current position, but also on its past trajectory. Examples of non-Markovian dynamics include single-file diffusion in narrow channels, or the motion of a tracer particle either attached to a polymeric chain or diffusing in simple or complex fluids such as nematics, dense soft colloids or viscoelastic solutions. Here we introduce an analytical approach to calculate, in the limit of a large confining volume, the mean first-passage time of a Gaussian non-Markovian random walker to a target. The non-Markovian features of the dynamics are encompassed by determining the statistical properties of the fictitious trajectory that the random walker would follow after the first-passage event takes place, which are shown to govern the first-passage time kinetics. This analysis is applicable to a broad range of stochastic processes, which may be correlated at long times. Our theoretical predictions are confirmed by numerical simulations for several examples of non-Markovian processes, including the case of fractional Brownian motion in one and higher dimensions. These results reveal, on the basis of Gaussian processes, the importance of memory effects in first-passage statistics of non-Markovian random walkers in confinement.

An Alternative Method for Computing Mean and Covariance Matrix of Some Multivariate Distributions

ERIC Educational Resources Information Center

Radhakrishnan, R.; Choudhury, Askar

2009-01-01

Computing the mean and covariance matrix of some multivariate distributions, in particular, multivariate normal distribution and Wishart distribution are considered in this article. It involves a matrix transformation of the normal random vector into a random vector whose components are independent normal random variables, and then integrating…

The effect of halogen light stimulation on duration of ultrasound parameters of biophysical profile: a randomized clinical trial.

PubMed

Hanafi, Mohammad Ghasem; Sahraeizadeh, Aliakbar

2018-02-22

The objective is to assess if fetal halogen light stimulation can reduce the time needed to obtain a normal biophysical profile (BPP). Patients scheduled for a BPP and who satisfied the inclusion criteria were prospectively randomized to halogen light stimulation and no stimulation groups. The study group was exposed to handheld halogen light for 10 s whenever fetal breathing, movement, or tone was absent through the first 5 min of BPP. The time required to achieve complete BPP score was recorded. In patients with complete BPP score who had delivery within 1 week after the test, perinatal morbidity was examined. A total of 598 patients were randomized (light = 302, no light = 296). There was no difference between the two groups in terms of gestational age, maternal age, body mass index, and indication for BPP except for preterm labor (light: 9%, no light: 4%, p = 0.03). Among the patients who had a normal BPP score (n = 507), the mean (light: 7.1 ± 6 min, no light: 12.3 ± 8 min, p < 0.0001) and median (light: 4.3, no light: 8, p = 0.004) time needed to complete the BPP score was significantly less in the light stimulation group than the no stimulation group. Perinatal outcomes were not different between groups who had delivery during the first week after BPP. Fetal halogen light stimulation can be utilized to reduce the time needed to complete a BPP. However, further studies should be conducted in order to determine the effect of this method on decreasing non-reassuring test results. The study was submitted to the Registry of Clinical Trials on 04/20/2017 (IRCT2017041633470N1). After IRCT registration on 06/07/2017, we recruited patients from 06/08/2017 till 10/15/2017.

A Randomized, Double Crossover Study to Investigate the Influence of Saline Infusion on Sleep Apnea Severity in Men

PubMed Central

Yadollahi, Azadeh; Gabriel, Joseph M.; White, Laura H.; Taranto Montemurro, Luigi; Kasai, Takatoshi; Bradley, T. Douglas

2014-01-01

Study Objectives: Obstructive sleep apnea (OSA) is commoner in patients with fluid-retaining states than in those without fluid retention, in men than in women, and worsens with aging. In men, OSA severity is related to the amount of fluid shifting out of the legs overnight, but a cause-effect relationship is not established. Our objective was to test the hypothesis that mimicking fluid overload during sleep would increase severity of OSA more in older (≥ 40 years) than in younger men (< 40 years). Design: Randomized, single-blind, double crossover study. Setting: Research sleep laboratory. Patients or Participants: Seven older and 10 younger men with non-severe or no sleep apnea, matched for body mass index. Interventions: During the control arm, normal saline was infused to keep the vein open. During intervention, subjects received an intravenous bolus of normal saline (22 mL/kg body weight) after sleep onset while they were wearing compression stockings to prevent fluid accumulation in the legs. Measurements and Results: Compared to younger men, infusion of similar amounts of saline in older men caused a greater increase in neck circumference (P < 0.05) and in the AHI (32.2 ± 22.1 vs. 2.2 ± 7.1, P = 0.002). Conclusions: Older men are more susceptible to the adverse effects of intravenous fluid loading on obstructive sleep apnea severity than younger men. This may be due to age-related differences in the amount of fluid accumulating in the neck or upper airway collapsibility in response to intravenous fluid loading. These possibilities remain to be tested in future studies. Citation: Yadollahi A, Gabriel JM, White LH, Taranto Montemurro L, Kasai T, Bradley TD. A randomized, double crossover study to investigate the influence of saline infusion on sleep apnea severity in men. SLEEP 2014;37(10):1699-1705. PMID:25197812

Expression of Folliculogenesis-Related Genes in Vitrified Human Ovarian Tissue after Two Weeks In Vitro Culture.

PubMed

Shams Mofarahe, Zahra; Salehnia, Mojdeh; Ghaffari Novin, Marefat; Ghorbanmehr, Nassim; Fesharaki, Mohammad Gholami

2017-01-01

This study was designed to evaluate the effects of vitrification and in vitro culture of human ovarian tissue on the expression of oocytic and follicular cell-related genes. In this experimental study, ovarian tissue samples were obtained from eight transsexual women. Samples were cut into small fragments and were then assigned to vitrified and non-vitrified groups. In each group, some tissue fragments were divided into un-cultured and cultured (in α-MEM medium for 2 weeks) subgroups. The normality of follicles was assessed by morphological observation under a light microscope using hematoxylin and eosin (H&E) staining. Expression levels of factor in the germ line alpha ( FIGLA ), KIT ligand ( KL ), growth differentiation factor 9 ( GDF-9 ) and follicle stimulating hormone receptor ( FSHR ) genes were quantified in both groups by real-time reverse transcriptase polymerase chain reaction (RT-PCR) at the beginning and the end of culture. The percentage of normal follicles was similar between non-cultured vitrified and non-vitrified groups (P>0.05), however, cultured tissues had significantly fewer normal follicles than non-cultured tissues in both vitrified and non-vitrified groups (P<0.05). In both cultured groups the rate of primary and secondary follicles was significantly higher than non-cultured tissues (P<0.05). The expression of all examined genes was not significantly altered in both non-cultured groups. Whiles, in comparison with cultured tissues non-cultured tissues, the expression of FIGLA gene was significantly decreased, KL gene was not changed, GDF-9 and FSHR genes was significantly increased (P<0.05). Human ovarian vitrification following in vitro culture has no impairing effects on follicle normality and development and expression of related-genes. However, in vitro culture condition has deleterious effects on normality of follicles.

Fast selection of miRNA candidates based on large-scale pre-computed MFE sets of randomized sequences.

PubMed

Warris, Sven; Boymans, Sander; Muiser, Iwe; Noback, Michiel; Krijnen, Wim; Nap, Jan-Peter

2014-01-13

Small RNAs are important regulators of genome function, yet their prediction in genomes is still a major computational challenge. Statistical analyses of pre-miRNA sequences indicated that their 2D structure tends to have a minimal free energy (MFE) significantly lower than MFE values of equivalently randomized sequences with the same nucleotide composition, in contrast to other classes of non-coding RNA. The computation of many MFEs is, however, too intensive to allow for genome-wide screenings. Using a local grid infrastructure, MFE distributions of random sequences were pre-calculated on a large scale. These distributions follow a normal distribution and can be used to determine the MFE distribution for any given sequence composition by interpolation. It allows on-the-fly calculation of the normal distribution for any candidate sequence composition. The speedup achieved makes genome-wide screening with this characteristic of a pre-miRNA sequence practical. Although this particular property alone will not be able to distinguish miRNAs from other sequences sufficiently discriminative, the MFE-based P-value should be added to the parameters of choice to be included in the selection of potential miRNA candidates for experimental verification.

Dynamic heterogeneity and non-Gaussian statistics for acetylcholine receptors on live cell membrane

NASA Astrophysics Data System (ADS)

He, W.; Song, H.; Su, Y.; Geng, L.; Ackerson, B. J.; Peng, H. B.; Tong, P.

2016-05-01

The Brownian motion of molecules at thermal equilibrium usually has a finite correlation time and will eventually be randomized after a long delay time, so that their displacement follows the Gaussian statistics. This is true even when the molecules have experienced a complex environment with a finite correlation time. Here, we report that the lateral motion of the acetylcholine receptors on live muscle cell membranes does not follow the Gaussian statistics for normal Brownian diffusion. From a careful analysis of a large volume of the protein trajectories obtained over a wide range of sampling rates and long durations, we find that the normalized histogram of the protein displacements shows an exponential tail, which is robust and universal for cells under different conditions. The experiment indicates that the observed non-Gaussian statistics and dynamic heterogeneity are inherently linked to the slow-active remodelling of the underlying cortical actin network.

Bilaterally cleft lip, limb defects, and haematological manifestations: Roberts syndrome versus TAR syndrome.

PubMed

Urban, M; Opitz, C; Bommer, C; Enders, H; Tinschert, S; Witkowski, R

1998-09-23

We report on a 13-year-old patient followed since birth. He is the only offspring of young, non-consanguineous German parents. His mother has an isolated left cleft of lip and a cleft palate. At birth, our patient presented with bilaterally cleft lip/cleft palate, phocomelia of upper limbs with normal hands, and mild symmetrical deficiencies of the long bones of the lower limbs. Haematological evaluation demonstrated a leukaemoid reaction during a urinary tract infection as well as intermittent thrombocytopenia and episodes of marked eosinophilia during the first two years of life. Intellectual development has been normal. Comparison with two similar cases from the literature suggests a non-random phenotypic overlap of Roberts syndrome (MIM 268300) and TAR syndrome (MIM 274000). Such clinical constellations may be key observations to understand the genetic relationship of Roberts syndrome and TAR syndrome in future phenotype-genotype correlations.

A heteroscedastic generalized linear model with a non-normal speed factor for responses and response times.

PubMed

Molenaar, Dylan; Bolsinova, Maria

2017-05-01

In generalized linear modelling of responses and response times, the observed response time variables are commonly transformed to make their distribution approximately normal. A normal distribution for the transformed response times is desirable as it justifies the linearity and homoscedasticity assumptions in the underlying linear model. Past research has, however, shown that the transformed response times are not always normal. Models have been developed to accommodate this violation. In the present study, we propose a modelling approach for responses and response times to test and model non-normality in the transformed response times. Most importantly, we distinguish between non-normality due to heteroscedastic residual variances, and non-normality due to a skewed speed factor. In a simulation study, we establish parameter recovery and the power to separate both effects. In addition, we apply the model to a real data set. © 2017 The Authors. British Journal of Mathematical and Statistical Psychology published by John Wiley & Sons Ltd on behalf of British Psychological Society.

Decrease of cardiac chaos in congestive heart failure

NASA Astrophysics Data System (ADS)

Poon, Chi-Sang; Merrill, Christopher K.

1997-10-01

The electrical properties of the mammalian heart undergo many complex transitions in normal and diseased states. It has been proposed that the normal heartbeat may display complex nonlinear dynamics, including deterministic chaos,, and that such cardiac chaos may be a useful physiological marker for the diagnosis and management, of certain heart trouble. However, it is not clear whether the heartbeat series of healthy and diseased hearts are chaotic or stochastic, or whether cardiac chaos represents normal or abnormal behaviour. Here we have used a highly sensitive technique, which is robust to random noise, to detect chaos. We analysed the electrocardiograms from a group of healthy subjects and those with severe congestive heart failure (CHF), a clinical condition associated with a high risk of sudden death. The short-term variations of beat-to-beat interval exhibited strongly and consistently chaotic behaviour in all healthy subjects, but were frequently interrupted by periods of seemingly non-chaotic fluctuations in patients with CHF. Chaotic dynamics in the CHF data, even when discernible, exhibited a high degree of random variability over time, suggesting a weaker form of chaos. These findings suggest that cardiac chaos is prevalent in healthy heart, and a decrease in such chaos may be indicative of CHF.

Effects of testosterone and nandrolone on cardiac function: a randomized, placebo-controlled study.

PubMed

Chung, T; Kelleher, S; Liu, P Y; Conway, A J; Kritharides, L; Handelsman, D J

2007-02-01

Androgens have striking effects on skeletal muscle, but the effects on human cardiac muscle function are not well defined, neither has the role of metabolic activation (aromatization, 5alpha reduction) of testosterone on cardiac muscle been directly studied. To assess the effects of testosterone and nandrolone, a non-amplifiable and non-aromatizable pure androgen, on cardiac muscle function in healthy young men. Double-blind, randomized, placebo-controlled, three-arm parallel group clinical trial. Ambulatory care research centre. Healthy young men randomized into three groups of 10 men. Weekly intramuscular injections of testosterone (200 mg mixed esters), nandrolone (200 mg nandrolone decanoate) or matching (2 ml arachis oil vehicle) placebo for 4 weeks. Comprehensive measures of cardiac muscle function involving transthoracic cardiac echocardiography measuring myocardial tissue velocity, peak systolic strain and strain rates, and bioimpedance measurement of cardiac output and systematic vascular resistance. Left ventricular (LV) function (LV ejection fraction, LV modified TEI index), right ventricular (RV) function (ejection area, tricuspid annular systolic planar motion, RV modified TEI index) as well as cardiac afterload (mean arterial pressure, systemic vascular resistance) and overall cardiac contractility (stroke volume, cardiac output) were within age- and gender-specific reference ranges and were not significantly (P < 0.05) altered by either androgen or placebo over 4 weeks of treatment. Minor changes remaining within normal range were observed solely within the testosterone group for: increased LV end-systolic diameter (30 +/- 7 vs. 33 +/- 5 mm, P = 0.04) and RV end-systolic area (12.8 +/- 1.3 vs. 14.6 +/- 3.3 cm(2), P = 0.04), reduced LV diastolic septal velocity (Em, 9.5 +/- 2.6 vs. 8.7 +/- 2.0 cm/s, P = 0.006), increased LV filling pressure (E/Em ratio, 7.1 +/- 1.6 vs. 8.3 +/- 1.8, P = 0.02) and shortened PR interval on the electrocardiogram (167 +/- 13 vs. 154 +/- 12, P = 0.03). Four weeks of treatment with testosterone or nandrolone had no beneficial or adverse effects compared with placebo on cardiac function in healthy young men.

Effect of dissolved oxygen in alcoholic beverages and drinking water on alcohol elimination in humans.

PubMed

Rhee, Su-jin; Chae, Jung-woo; Song, Byung-jeong; Lee, Eun-sil; Kwon, Kwang-il

2013-02-01

Oxygen plays an important role in the metabolism of alcohol. An increased dissolved oxygen level in alcoholic beverages reportedly accelerates the elimination of alcohol. Therefore, we evaluated the effect of dissolved oxygen in alcohol and the supportive effect of oxygenated water on alcohol pharmacokinetics after the excessive consumption of alcohol, i.e., 540 ml of 19.5% alcohol (v/v). Fifteen healthy males were included in this randomized, 3 × 3 crossover study. Three combinations were tested: X, normal alcoholic beverage and normal water; Y, oxygenated alcoholic beverage and normal water; Z, oxygenated alcoholic beverage and oxygenated water. Blood alcohol concentrations (BACs) were determined by conversion of breath alcohol concentrations. Four pharmacokinetic parameters (C(max), T(max), K(el), and AUCall) were obtained using non-compartmental analysis and the times to reach 0.05% and 0.03% BAC (T(0.05%) and T(0.03%)) were compared using one-way analysis of variance (ANOVA) and Duncan's post hoc test. With combination Z, the BAC decreased to 0.05% significantly faster (p < 0.05) than with combination X. Analyzing the pharmacokinetic parameters, the mean K(el) was significantly higher for combination Z than for combinations X and Y (p < 0.05), whereas the mean values of C(max), T(max) and AUCall did not differ significantly among the combinations. Dissolved oxygen in drinks accelerates the decrease in BAC after consuming a large amount of alcohol. However, the oxygen dissolved in the alcoholic beverage alone did not have a sufficient effect in this case. We postulate that highly oxygenated water augments the effect of oxygen in the alcoholic beverage in alcohol elimination. Therefore, it is necessary to investigate the supportive effect of ingesting additional oxygenated water after heavy drinking of normal alcoholic beverages. Copyright © 2013 Elsevier Inc. All rights reserved.

The effect of fast and regeneration in light versus dark on regulation in the hydra-algal symbiosis

NASA Technical Reports Server (NTRS)

Bossert, P.; Slobodkin, L. B.

1983-01-01

Green hydra are able to regenerate tentacles after fast durations which cause brown, i.e., asymbiotic, hydra to fail completely, but the presence of endosymbiotic algae does not always enhance regeneration in fasted hydra. Green hydra whose nutritional state falls below some threshold, exhibit a light induced inhibition of regeneration. That is, hydra, fasted in the light, then randomly assigned to light or dark after decapitation, regenerate better in the dark. This effect of light does not appear to be present either in brown hydra or in normally green hydra from which the algae were removed. In a large strain of Chlorohydra viridissima, after fasts of intermediate duration (10 and 15 days), this light induced inhibition of regeneration is associated with an increase in the number of algae per gastric cell in regenerating hydra relative to non-regenerating controls.

[Position paper on the results of Symplicity HTN-3 trial. Grupo de estudio de la hipertensión arterial resistente].

PubMed

Azpiri-López, José Ramón; Assad-Morell, José Luis; Ponce de León-Martínez, Enrique; Monreal-Puente, Rogelio; Dávila-Bortoni, Adrián; Vázquez-Díaz, Luis Alberto; Treviño-Frutos, Ramón Javier; Barrera-Oranday, Félix; Del Angel-Soto, Juan Gustavo; Martínez, José Guadalupe; Arellano-Torres, Marcelo

2015-01-01

Renal artery denervation has shown to be an effective treatment for resistant hypertension. Symplicity HTN 1 and 2 trials showed in small and uncontrolled groups, significant systolic blood pressure reductions down to 30 mm Hg. Symplicity HTN-3, a double blind, randomized, placebo controlled clinical trial shaded this initial enthusiasm. Surprisingly, their results showed that renal denervation has a similar effect to placebo. Pre-specified subgroup analysis showed that non-black race individuals, younger than 65 years and with normal renal function, had a statistically significant systolic blood pressure decrease. This manuscript critically appraises the Symplicity HTN-3 trial, proposing possible explanations for the results. Also declares our group position and future actions regarding renal denervation. Copyright © 2014 Instituto Nacional de Cardiología Ignacio Chávez. Published by Masson Doyma México S.A. All rights reserved.

Meta-analysis of prediction model performance across multiple studies: Which scale helps ensure between-study normality for the C-statistic and calibration measures?

PubMed

Snell, Kym Ie; Ensor, Joie; Debray, Thomas Pa; Moons, Karel Gm; Riley, Richard D

2017-01-01

If individual participant data are available from multiple studies or clusters, then a prediction model can be externally validated multiple times. This allows the model's discrimination and calibration performance to be examined across different settings. Random-effects meta-analysis can then be used to quantify overall (average) performance and heterogeneity in performance. This typically assumes a normal distribution of 'true' performance across studies. We conducted a simulation study to examine this normality assumption for various performance measures relating to a logistic regression prediction model. We simulated data across multiple studies with varying degrees of variability in baseline risk or predictor effects and then evaluated the shape of the between-study distribution in the C-statistic, calibration slope, calibration-in-the-large, and E/O statistic, and possible transformations thereof. We found that a normal between-study distribution was usually reasonable for the calibration slope and calibration-in-the-large; however, the distributions of the C-statistic and E/O were often skewed across studies, particularly in settings with large variability in the predictor effects. Normality was vastly improved when using the logit transformation for the C-statistic and the log transformation for E/O, and therefore we recommend these scales to be used for meta-analysis. An illustrated example is given using a random-effects meta-analysis of the performance of QRISK2 across 25 general practices.

An inexact log-normal distribution-based stochastic chance-constrained model for agricultural water quality management

NASA Astrophysics Data System (ADS)

Wang, Yu; Fan, Jie; Xu, Ye; Sun, Wei; Chen, Dong

2018-05-01

In this study, an inexact log-normal-based stochastic chance-constrained programming model was developed for solving the non-point source pollution issues caused by agricultural activities. Compared to the general stochastic chance-constrained programming model, the main advantage of the proposed model is that it allows random variables to be expressed as a log-normal distribution, rather than a general normal distribution. Possible deviations in solutions caused by irrational parameter assumptions were avoided. The agricultural system management in the Erhai Lake watershed was used as a case study, where critical system factors, including rainfall and runoff amounts, show characteristics of a log-normal distribution. Several interval solutions were obtained under different constraint-satisfaction levels, which were useful in evaluating the trade-off between system economy and reliability. The applied results show that the proposed model could help decision makers to design optimal production patterns under complex uncertainties. The successful application of this model is expected to provide a good example for agricultural management in many other watersheds.

Amyloplasts That Sediment in Protonemata of the Moss Ceratodon purpureus Are Nonrandomly Distributed in Microgravity1

PubMed Central

Kern, Volker D.; Smith, Jeffrey D.; Schwuchow, Jochen M.; Sack, Fred D.

2001-01-01

Little is known about whether or how plant cells regulate the position of heavy organelles that sediment toward gravity. Dark-grown protonemata of the moss Ceratodon purpureus displays a complex plastid zonation in that only some amyloplasts sediment along the length of the tip cell. If gravity is the major force determining the position of amyloplasts that sediment, then these plastids should be randomly distributed in space. Instead, amyloplasts were clustered in the subapical region in microgravity. Cells rotated on a clinostat on earth had a roughly similar non-random plastid distribution. Subapical clusters were also found in ground controls that were inverted and kept stationary, but the distribution profile differed considerably due to amyloplast sedimentation. These findings indicate the existence of as yet unknown endogenous forces and mechanisms that influence amyloplast position and that are normally masked in stationary cells grown on earth. It is hypothesized that a microtubule-based mechanism normally compensates for g-induced drag while still allowing for regulated amyloplast sedimentation. PMID:11299388

Superdiffusion, large-scale synchronization, and topological defects

NASA Astrophysics Data System (ADS)

Großmann, Robert; Peruani, Fernando; Bär, Markus

2016-04-01

We study an ensemble of random walkers carrying internal noisy phase oscillators which are synchronized among the walkers by local interactions. Due to individual mobility, the interaction partners of every walker change randomly, hereby introducing an additional, independent source of fluctuations, thus constituting the intrinsic nonequilibrium nature of the temporal dynamics. We employ this paradigmatic model system to discuss how the emergence of order is affected by the motion of individual entities. In particular, we consider both normal diffusive motion and superdiffusion. A non-Hamiltonian field theory including multiplicative noise terms is derived which describes the nonequilibrium dynamics at the macroscale. This theory reveals a defect-mediated transition from incoherence to quasi-long-range order for normal diffusion of oscillators in two dimensions, implying a power-law dependence of all synchronization properties on system size. In contrast, superdiffusive transport suppresses the emergence of topological defects, thereby inducing a continuous synchronization transition to long-range order in two dimensions. These results are consistent with particle-based simulations.

Group normalization for genomic data.

PubMed

Ghandi, Mahmoud; Beer, Michael A

2012-01-01

Data normalization is a crucial preliminary step in analyzing genomic datasets. The goal of normalization is to remove global variation to make readings across different experiments comparable. In addition, most genomic loci have non-uniform sensitivity to any given assay because of variation in local sequence properties. In microarray experiments, this non-uniform sensitivity is due to different DNA hybridization and cross-hybridization efficiencies, known as the probe effect. In this paper we introduce a new scheme, called Group Normalization (GN), to remove both global and local biases in one integrated step, whereby we determine the normalized probe signal by finding a set of reference probes with similar responses. Compared to conventional normalization methods such as Quantile normalization and physically motivated probe effect models, our proposed method is general in the sense that it does not require the assumption that the underlying signal distribution be identical for the treatment and control, and is flexible enough to correct for nonlinear and higher order probe effects. The Group Normalization algorithm is computationally efficient and easy to implement. We also describe a variant of the Group Normalization algorithm, called Cross Normalization, which efficiently amplifies biologically relevant differences between any two genomic datasets.

Group Normalization for Genomic Data

PubMed Central

Ghandi, Mahmoud; Beer, Michael A.

2012-01-01

Data normalization is a crucial preliminary step in analyzing genomic datasets. The goal of normalization is to remove global variation to make readings across different experiments comparable. In addition, most genomic loci have non-uniform sensitivity to any given assay because of variation in local sequence properties. In microarray experiments, this non-uniform sensitivity is due to different DNA hybridization and cross-hybridization efficiencies, known as the probe effect. In this paper we introduce a new scheme, called Group Normalization (GN), to remove both global and local biases in one integrated step, whereby we determine the normalized probe signal by finding a set of reference probes with similar responses. Compared to conventional normalization methods such as Quantile normalization and physically motivated probe effect models, our proposed method is general in the sense that it does not require the assumption that the underlying signal distribution be identical for the treatment and control, and is flexible enough to correct for nonlinear and higher order probe effects. The Group Normalization algorithm is computationally efficient and easy to implement. We also describe a variant of the Group Normalization algorithm, called Cross Normalization, which efficiently amplifies biologically relevant differences between any two genomic datasets. PMID:22912661

Evaluation of Bias-Variance Trade-Off for Commonly Used Post-Summarizing Normalization Procedures in Large-Scale Gene Expression Studies

PubMed Central

Qiu, Xing; Hu, Rui; Wu, Zhixin

2014-01-01

Normalization procedures are widely used in high-throughput genomic data analyses to remove various technological noise and variations. They are known to have profound impact to the subsequent gene differential expression analysis. Although there has been some research in evaluating different normalization procedures, few attempts have been made to systematically evaluate the gene detection performances of normalization procedures from the bias-variance trade-off point of view, especially with strong gene differentiation effects and large sample size. In this paper, we conduct a thorough study to evaluate the effects of normalization procedures combined with several commonly used statistical tests and MTPs under different configurations of effect size and sample size. We conduct theoretical evaluation based on a random effect model, as well as simulation and biological data analyses to verify the results. Based on our findings, we provide some practical guidance for selecting a suitable normalization procedure under different scenarios. PMID:24941114

Individual mineral supplement intake by ewes swath grazing or confinement fed pea-barley forage

USDA-ARS?s Scientific Manuscript database

Sixty mature ewes (non-pregnant, non-lactating) were used in a completely randomized design to determine if feeding method of pea-barley forage (swath grazing or hay in confinement) had an effect on individual ewe mineral consumption. Thirty ewes were randomly allocated to 3 confinement pens and 30 ...

Diagnostic utility, safety, and cost-effectiveness of emergency department-initiated early scheduled technetium-99m single photon emission computed tomography imaging followed by expedited outpatient cardiac clinic visits in acute chest pain syndromes.

PubMed

Wong, Raymond C; Sinha, Arvind Kumar; Mahadevan, Malcolm; Yeo, Tiong Cheng

2010-09-01

Conventional emergency department (EMD) approach to triaging acute chest pain syndromes may lead to unnecessary admissions, resulting to in-hospital bed occupancy and increased healthcare costs. We explore the diagnostic utility of early (less than a week) outpatient scheduled single photon emission computed tomography (SPECT) in intermediate-risk chest pain subjects who presented to EMD with non-diagnostic electrocardiogram and negative serum troponin level. Additionally, we intend to study the safety and cost-effectiveness of such a strategy. We conduct a prospective, non-randomized study of 108 subjects who fit the inclusion criteria. After SPECT studies, all subjects were evaluated in the cardiac clinic within 2 weeks of EMD visits. Final diagnosis of coronary artery disease and subsequent disposition to standard medical therapy or follow-on angiography were decided by incorporating pre-test clinical data and SPECT results. Adverse events defined as myocardial infarction and cardiac death was tracked between EMD visit and eventual therapy (either medical therapy or coronary revascularization). Finally, cost-effectiveness was determined based on estimated cost and days of hospitalization saved between standard strategies of ward admission for further evaluation versus the present early outpatient SPECT-based workflow. Among 108 subjects (mean age 58 years, 59% male) included for analysis, 82 (76%) had normal perfusion status. There was no statistical difference in baseline characteristics and prior ischemic heart disease history between groups. In the 26 abnormal perfusion subjects, seven had follow-on coronary angiography in which three were found to have significant stenotic coronary lesions, but only one had intervention performed. There was an unscheduled coronary angiography in the normal perfusion group that yielded normal coronary anatomy. There was no adverse clinical event in both groups. Compared with standard strategy, early outpatient SPECT initiated by EMD physicians followed by cardiac clinic evaluation resulted in 2.9 days of hospitalization or $781.23 saved per patient per EMD visit. EMD-initiated early SPECT studies followed by cardiac clinic evaluation in intermediate-risk acute chest pain syndromes with non-diagnostic ECG and negative serum troponin levels carries excellent diagnostic and therapeutic utility, in addition to being safe and cost-effective.

Effects of 6-Week Use of Reduced-Nicotine Content Cigarettes in Smokers With and Without Elevated Depressive Symptoms.

PubMed

Tidey, Jennifer W; Pacek, Lauren R; Koopmeiners, Joseph S; Vandrey, Ryan; Nardone, Natalie; Drobes, David J; Benowitz, Neal L; Dermody, Sarah S; Lemieux, Andrine; Denlinger, Rachel L; Cassidy, Rachel; al'Absi, Mustafa; Hatsukami, Dorothy K; Donny, Eric C

2017-01-01

The FDA recently acquired regulatory authority over tobacco products, leading to renewed interest in whether reducing the nicotine content of cigarettes would reduce tobacco dependence in the United States. Given the association between depressive symptoms and cigarette smoking, it is important to consider whether smokers with elevated depressive symptoms experience unique benefits or negative consequences of nicotine reduction. In this secondary analysis of a randomized clinical trial that examined the effects of cigarettes varying in nicotine content over a 6-week period in non-treatment-seeking smokers, we used linear regression to examine whether baseline depressive symptom severity (scores on the Center for Epidemiologic Studies Depression Scale [CES-D]) moderated the effects of reduced-nicotine content (RNC) cigarettes, relative to normal-nicotine content (NNC) cigarettes, on smoking rates, depressive symptom severity, and related subjective and physiological measures. Of the 717 participants included in this analysis, 109 (15.2%) had CES-D scores ≥ 16, indicative of possible clinical depression. Relative to NNC cigarettes, RNC cigarettes reduced smoking rates, nicotine dependence, and cigarette craving, and these effects were not significantly moderated by baseline CES-D score. A significant interaction between baseline CES-D score and cigarette condition on week 6 CES-D score was observed (p < .05); among those with CES-D scores ≥ 16 at baseline, those assigned to RNC cigarettes had lower week 6 CES-D scores than those assigned to NNC cigarettes. Among those in the lowest nicotine content conditions, biochemically confirmed compliance with the RNC cigarettes was associated with an increase in CES-D score for those with baseline CES-D scores < 16 and no change in CES-D score for those with baseline CES-D scores ≥ 16. These findings provide initial evidence that a reduced-nicotine standard for cigarettes may reduce smoking, without worsening depressive symptoms, among smokers with elevated depressive symptoms. This secondary analysis of a recent clinical trial examined whether depressive symptom severity moderated the effects of reduced-nicotine cigarettes on smoking and depressive symptoms. Results indicate that, regardless of baseline depressive symptoms, participants randomized to reduced-nicotine cigarettes had lower smoking rates, nicotine intake, nicotine dependence, and craving at week 6 post-randomization than those assigned to normal-nicotine cigarettes. In participants with higher baseline depressive symptoms, those assigned to reduced-nicotine cigarettes had lower week 6 depressive symptoms than those assigned to normal-nicotine cigarettes. These results suggest that a nicotine reduction policy could have beneficial effects for smokers, regardless of depressive symptom severity. © The Author 2016. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Parameter estimation of multivariate multiple regression model using bayesian with non-informative Jeffreys’ prior distribution

NASA Astrophysics Data System (ADS)

Saputro, D. R. S.; Amalia, F.; Widyaningsih, P.; Affan, R. C.

2018-05-01

Bayesian method is a method that can be used to estimate the parameters of multivariate multiple regression model. Bayesian method has two distributions, there are prior and posterior distributions. Posterior distribution is influenced by the selection of prior distribution. Jeffreys’ prior distribution is a kind of Non-informative prior distribution. This prior is used when the information about parameter not available. Non-informative Jeffreys’ prior distribution is combined with the sample information resulting the posterior distribution. Posterior distribution is used to estimate the parameter. The purposes of this research is to estimate the parameters of multivariate regression model using Bayesian method with Non-informative Jeffreys’ prior distribution. Based on the results and discussion, parameter estimation of β and Σ which were obtained from expected value of random variable of marginal posterior distribution function. The marginal posterior distributions for β and Σ are multivariate normal and inverse Wishart. However, in calculation of the expected value involving integral of a function which difficult to determine the value. Therefore, approach is needed by generating of random samples according to the posterior distribution characteristics of each parameter using Markov chain Monte Carlo (MCMC) Gibbs sampling algorithm.

The effects of Sahaja Yoga meditation on mental health: a systematic review.

PubMed

Hendriks, Tom

2018-05-30

Objectives To determine the efficacy of Sahaja Yoga (SY) meditation on mental health among clinical and healthy populations. Methods All publications on SY were eligible. Databases were searched up to November 2017, namely PubMed, MEDLINE (NLM), PsychINFO, and Scopus. An internet search (Google Scholar) was also conducted. The quality of the randomized controlled trails was assessed using the Cochrane Risk Assessment for Bias. The quality of cross-sectional studies, a non-randomized controlled trial and a cohort study was assessed with the Newcastle-Ottawa Quality Assessment Scale. Results We included a total of eleven studies; four randomized controlled trials, one non-randomized controlled trial, five cross-sectional studies, and one prospective cohort study. The studies included a total of 910 participants. Significant findings were reported in relation to the following outcomes: anxiety, depression, stress, subjective well-being, and psychological well-being. Two randomized studies were rated as high quality studies, two randomized studies as low quality studies. The quality of the non-randomized trial, the cross-sectional studies and the cohort study was high. Effect sizes could not be calculated in five studies due to unclear or incomplete reporting. Conclusions After reviewing the articles and taking the quality of the studies into account, it appears that SY may reduce depression and possibly anxiety. In addition, the practice of SY is also associated with increased subjective wellbeing and psychological well-beng. However, due to the limited number of publications, definite conclusions on the effects of SY cannot be made and more high quality randomized studies are needed to justify any firm conclusions on the beneficial effects of SY on mental health.

Moderate plasma activated media suppresses proliferation and migration of MDCK epithelial cells

NASA Astrophysics Data System (ADS)

Mohades, Soheila; Laroussi, Mounir; Maruthamuthu, Venkat

2017-05-01

Low-temperature plasma has been shown to have diverse biomedical uses, including its applications in cancer and wound healing. One recent approach in treating mammalian cells with plasma is through the use of plasma activated media (PAM), which is produced by exposing cell culture media to plasma. While the adverse effects of PAM treatment on cancerous epithelial cell lines have been recently studied, much less is known about the interaction of PAM with normal epithelial cells. In this paper, non-cancerous canine kidney MDCK (Madin-Darby Canine Kidney) epithelial cells were treated by PAM and time-lapse microscopy was used to directly monitor their proliferation and random migration upon treatment. While longer durations of PAM treatment led to cell death, we found that moderate levels of PAM treatment inhibited proliferation in these epithelial cells. We also found that PAM treatment reduced random cell migration within epithelial islands. Immunofluorescence staining showed that while there were no major changes in the actin/adhesion apparatus, there was a significant change in the nuclear localization of proliferation marker Ki-67, consistent with our time-lapse results.

X-irradiation of human bronchial cancer cells causes the bystander effects in normal bronchial cells in vitro.

PubMed

Konopacka, M; Rogoliński, J

2010-01-01

Using X radiation commonly used in radiotherapy of cancers we investigated bystander interactions between human cells: irradiated A549 bronchial carcinoma human cells and non irradiated BEAS-2B normal bronchial epithelial cells. Non irradiated cells were incubated in medium transferred from irradiated A549 cells (ICM-irradiation conditioned medium) for 48h and next the chromosomal damage and apoptosis were estimated. Conditioned medium collected from irradiated cancer cells induced in non irradiated cells of the same line as well as in BEAS-2B normal cells genetic changes such as micronuclei, chromatid and chromosomal breaks and condensation of chromatin characteristic for processes of apoptosis. Addition of only 1% of conditioned medium to fresh medium was sufficient to induction of bystander response to normal bronchial cells. The presented results in this study could have implications for human radiation risk and in evaluating the secondary effects of radiotherapy.

Effects of exercise and diet interventions on obesity-related sleep disorders in men: study protocol for a randomized controlled trial.

PubMed

Tan, Xiao; Saarinen, Antti; Mikkola, Tuija M; Tenhunen, Jarkko; Martinmäki, Samu; Rahikainen, Aki; Cheng, Shumei; Eklund, Niklas; Pekkala, Satu; Wiklund, Petri; Munukka, Eveliina; Wen, Xinfei; Cong, Fengyu; Wang, Xi; Zhang, Yajun; Tarkka, Ina; Sun, Yining; Partinen, Markku; Alen, Markku; Cheng, Sulin

2013-07-26

Sleep is essential for normal and healthy living. Lack of good quality sleep affects physical, mental and emotional functions. Currently, the treatments of obesity-related sleep disorders focus more on suppressing sleep-related symptoms pharmaceutically and are often accompanied by side effects. Thus, there is urgent need for alternative ways to combat chronic sleep disorders. This study will investigate underlying mechanisms of the effects of exercise and diet intervention on obesity-related sleep disorders, the role of gut microbiota in relation to poor quality of sleep and day-time sleepiness, as well as the levels of hormones responsible for sleep-wake cycle regulation. Participants consist of 330 (target sample) Finnish men aged 30 to 65 years. Among them, we attempt to randomize 180 (target sample) with sleep disorders into exercise and diet intervention. After screening and physician examination, 101 men with sleep disorders are included and are randomly assigned into three groups: exercise (n = 33), diet (n = 35), and control (n = 33). In addition, we attempt to recruit a target number of 150 healthy men without sleep disorders as the reference group. The exercise group undergoes a six-month individualized progressive aerobic exercise program based on initial fitness level. The diet group follows a six month specific individualized diet program. The control group and reference group are asked to maintain their normal activity and diet during intervention. Measurements are taken before and after the intervention. Primary outcomes include objective sleep measurements by polysomnography and a home-based non-contact sleep monitoring system, and subjective sleep evaluation by questionnaires. Secondary outcome measures include anthropometry, body composition, fitness, sleep disorder-related lifestyle risk factors, composition of gut microbiota and adipose tissue metabolism, as well as specific hormone and neurotranmitter levels and inflammatory biomarkers from venous blood samples. It is expected that the improvement of sleep quality after exercise and diet intervention will be evident both in subjective and objective measures of quality of sleep. Additionally, the change of sleep quality induced by exercise and diet intervention is expected to be related to the changes in specific hormones and inflammatory biomarkers, and in the composition of gut microbiota.

Cancelable biometrics realization with multispace random projections.

PubMed

Teoh, Andrew Beng Jin; Yuang, Chong Tze

2007-10-01

Biometric characteristics cannot be changed; therefore, the loss of privacy is permanent if they are ever compromised. This paper presents a two-factor cancelable formulation, where the biometric data are distorted in a revocable but non-reversible manner by first transforming the raw biometric data into a fixed-length feature vector and then projecting the feature vector onto a sequence of random subspaces that were derived from a user-specific pseudorandom number (PRN). This process is revocable and makes replacing biometrics as easy as replacing PRNs. The formulation has been verified under a number of scenarios (normal, stolen PRN, and compromised biometrics scenarios) using 2400 Facial Recognition Technology face images. The diversity property is also examined.

Mechanisms for an effect of acetylcysteine on renal function after exposure to radio-graphic contrast material: study protocol

PubMed Central

2012-01-01

Background Contrast-induced nephropathy is a common complication of contrast administration in patients with chronic kidney disease and diabetes. Its pathophysiology is not well understood; similarly the role of intravenous or oral acetylcysteine is unclear. Randomized controlled trials to date have been conducted without detailed knowledge of the effect of acetylcysteine on renal function. We are conducting a detailed mechanistic study of acetylcysteine on normal and impaired kidneys, both with and without contrast. This information would guide the choice of dose, route, and appropriate outcome measure for future clinical trials in patients with chronic kidney disease. Methods/Design We designed a 4-part study. We have set up randomised controlled cross-over studies to assess the effect of intravenous (50 mg/kg/hr for 2 hrs before contrast exposure, then 20 mg/kg/hr for 5 hrs) or oral acetylcysteine (1200 mg twice daily for 2 days, starting the day before contrast exposure) on renal function in normal and diseased kidneys, and normal kidneys exposed to contrast. We have also set up a parallel-group randomized controlled trial to assess the effect of intravenous or oral acetylcysteine on patients with chronic kidney disease stage III undergoing elective coronary angiography. The primary outcome is change in renal blood flow; secondary outcomes include change in glomerular filtration rate, tubular function, urinary proteins, and oxidative balance. Discussion Contrast-induced nephropathy represents a significant source of hospital morbidity and mortality. Over the last ten years, acetylcysteine has been administered prior to contrast to reduce the risk of contrast-induced nephropathy. Randomized controlled trials, however, have not reliably demonstrated renoprotection; a recent large randomized controlled trial assessing a dose of oral acetylcysteine selected without mechanistic insight did not reduce the incidence of contrast-induced nephropathy. Our study should reveal the mechanism of effect of acetylcysteine on renal function and identify an appropriate route for future dose response studies and in time randomized controlled trials. Trial registration Clinical Trials.gov: NCT00558142; EudraCT: 2006-003509-18. PMID:22305183

DOE Office of Scientific and Technical Information (OSTI.GOV)

Harner, E.J.; Gilfillan, E.S.

Two large shoreline assessment studies conducted in 1990 in Prince William Sound, Alaska, after the Exxon Valdez oil spill used different design strategies to determine the impact of oiling on shoreline biota. One of the studies, the Coastal Habitat Injury Assessment (CHIA) conducted for the Exxon Valdez Oil Spill Council, used matched pairs of sites, normal population distributions for biota, and meta-analysis. The power of the CHIA study to detect oiling impacts depends on being able to identify and select appropriate pairs of sites for comparison. The CHIA study also increased the oiling signal by focusing on moderate to heavilymore » oiled sites. The Shoreline Ecology Program (SEP), conducted for Exxon, used a stratified-random-sampling study design, normal and non-normal population distributions and covariates. The SEP study was able to detect oiling impacts by using a sufficient number of sites and widely spaced transects.« less

Bioinspired artificial photonic nanoarchitecture using the elytron of the beetle Trigonophorus rothschildi varians as a ‘blueprint’

PubMed Central

Biró, L. P.; Kertész, K.; Horváth, E.; Márk, G. I.; Molnár, G.; Vértesy, Z.; Tsai, J.-F.; Kun, A.; Bálint, Zs.; Vigneron, J. P.

2010-01-01

An unusual, intercalated photonic nanoarchitecture was discovered in the elytra of Taiwanese Trigonophorus rothschildi varians beetles. It consists of a multilayer structure intercalated with a random distribution of cylindrical holes normal to the plane of the multilayer. The nanoarchitectures were characterized structurally by scanning electron microscopy and optically by normal incidence, integrated and goniometric reflectance measurements. They exhibit an unsaturated specular and saturated non-specular component of the reflected light. Bioinspired, artificial nanoarchitectures of similar structure and with similar properties were realized by drilling holes of submicron size in a multilayer structure, showing that such photonic nanoarchitectures of biological origin may constitute valuable blueprints for artificial photonic materials. PMID:19933221

Origins and nature of non-Fickian transport through fractures

NASA Astrophysics Data System (ADS)

Wang, L.; Cardenas, M. B.

2014-12-01

Non-Fickian transport occurs across all scales within fractured and porous geological media. Fundamental understanding and appropriate characterization of non-Fickian transport through fractures is critical for understanding and prediction of the fate of solutes and other scalars. We use both analytical and numerical modeling, including direct numerical simulation and particle tracking random walk, to investigate the origin of non-Fickian transport through both homogeneous and heterogeneous fractures. For the simple homogenous fracture case, i.e., parallel plates, we theoretically derived a formula for dynamic longitudinal dispersion (D) within Poiseuille flow. Using the closed-form expression for the theoretical D, we quantified the time (T) and length (L) scales separating preasymptotic and asymptotic dispersive transport, with T and L proportional to aperture (b) of parallel plates to second and fourth orders, respectively. As for heterogeneous fractures, the fracture roughness and correlation length are closely associated with the T and L, and thus indicate the origin for non-Fickian transport. Modeling solute transport through 2D rough-walled fractures with continuous time random walk with truncated power shows that the degree of deviation from Fickian transport is proportional to fracture roughness. The estimated L for 2D rough-walled fractures is significantly longer than that derived from the formula within Poiseuille flow with equivalent b. Moreover, we artificially generated normally distributed 3D fractures with fixed correlation length but different fracture dimensions. Solute transport through 3D fractures was modeled with a particle tracking random walk algorithm. We found that transport transitions from non-Fickian to Fickian with increasing fracture dimensions, where the estimated L for the studied 3D fractures is related to the correlation length.

Bone mineral density and effects of growth hormone treatment in prepubertal children with Prader-Willi syndrome: a randomized controlled trial.

PubMed

de Lind van Wijngaarden, Roderick F A; Festen, Dederieke A M; Otten, Barto J; van Mil, Edgar G A H; Rotteveel, Joost; Odink, Roelof J; van Leeuwen, Mariëtte; Haring, Danny A J P; Bocca, Gianni; Mieke Houdijk, E C A; Hokken-Koelega, Anita C S

2009-10-01

Bone mineral density (BMD) is unknown in children with Prader-Willi syndrome (PWS), but is decreased in adults with PWS. In patients with GH deficiency, BMD increases during GH treatment. The aim of the study was to evaluate BMD in children with PWS and to study the effects of GH treatment. We conducted a randomized controlled GH trial. Forty-six prepubertal children were randomized into either a GH-treated group (1.0 mg/m(2) . d) or a control group for 2 yr. At start, 6, 12, and 24 months of study, total body and lumbar spine BMD were measured by dual-energy x-ray absorptiometry, and lumbar spine bone mineral apparent density (BMAD) was calculated. Baseline total body and lumbar spine BMD sd score (SDS) were normal [mean (sd), -0.2 SDS (1.1) and -0.4 SDS (1.2), respectively]. BMADSDS, which corrects for short stature, was also normal [mean (sd), 0.40 SDS (1.1)]. Total body BMDSDS decreased during the first 6 months of GH (P < 0.0001), but increased during the second year of treatment. After 24 months of study, total body and lumbar spine BMDSDS, and the BMADSDS did not significantly differ between GH-treated children and randomized controls (P = 0.30, P = 0.44, and P = 0.47, respectively). Results were similar when corrected for body mass index SDS. Repeated measurements analysis showed a significant positive association between IGF-I SDS and total body and lumbar spine BMDSDS, but not with BMADSDS. Our results show that prepubertal children with PWS have a normal BMD. GH treatment had no effect on BMD, except for a temporary decrease of total body BMDSDS in the first 6 months.

Magnesium in cardioplegia: Is it necessary?

PubMed Central

Shakerinia, Tooraj; Ali, Idris M.; Sullivan, John A.P.

1996-01-01

Objective To study the effectiveness of magnesium in cardioplegic solution in preventing postoperative arrhythmias and perioperative ischemia. Design Randomized, control study. Setting The cardiovascular surgery division of a major referral centre for the maritime provinces of Canada. Patients Fifty patients scheduled to undergo coronary artery bypass who had a normal ejection fraction, normal preoperative serum magnesium level and no history of atrial or ventricular arrhythmia were randomized into two groups of 25 patients. One group received magnesium sulfate (15 mmol/L) in the cardioplegic solution (group 1), the other (control) group did not receive magnesium sulfate in the cardioplegic solution (group 2). Intervention Coronary artery bypass grafting during which myocardial protection was provided by intermittent cold blood cardioplegia. Outcome Measures Postoperative serum magnesium levels, cardiac-related death, infarction and arrhythmias. Results All group 2 patients had a lower postoperative serum magnesium level than group 1 patients. There were no cardiac-related deaths in either group. More group 2 patients had ischemic electrocardiographic changes than group 1 patients (p < 0.03). Non-Q-wave myocardial infarction occurred in two patients (one in each group). Eight patients in group 2 had atrial fibrillation compared with five patients in group 1. Ventricular ectopia occurred significantly (p < 0.01) more frequently in group 2 than in group 1. Conclusion The addition of magnesium to the cardioplegic solution is beneficial in reducing the incidence of perioperative ischemia and ventricular arrhythmia in patients who undergo coronary bypass grafting. PMID:8857989

Examining non-syndromic autosomal recessive intellectual disability (NS-ARID) genes for an enriched association with intelligence differences☆

PubMed Central

Hill, W.D.; Davies, G.; Liewald, D.C.; Payton, A.; McNeil, C.J.; Whalley, L.J.; Horan, M.; Ollier, W.; Starr, J.M.; Pendleton, N.; Hansel, N.K.; Montgomery, G.W.; Medland, S.E.; Martin, N.G.; Wright, M.J.; Bates, T.C.; Deary, I.J.

2016-01-01

Two themes are emerging regarding the molecular genetic aetiology of intelligence. The first is that intelligence is influenced by many variants and those that are tagged by common single nucleotide polymorphisms account for around 30% of the phenotypic variation. The second, in line with other polygenic traits such as height and schizophrenia, is that these variants are not randomly distributed across the genome but cluster in genes that work together. Less clear is whether the very low range of cognitive ability (intellectual disability) is simply one end of the normal distribution describing individual differences in cognitive ability across a population. Here, we examined 40 genes with a known association with non-syndromic autosomal recessive intellectual disability (NS-ARID) to determine if they are enriched for common variants associated with the normal range of intelligence differences. The current study used the 3511 individuals of the Cognitive Ageing Genetics in England and Scotland (CAGES) consortium. In addition, a text mining analysis was used to identify gene sets biologically related to the NS-ARID set. Gene-based tests indicated that genes implicated in NS-ARID were not significantly enriched for quantitative trait loci (QTL) associated with intelligence. These findings suggest that genes in which mutations can have a large and deleterious effect on intelligence are not associated with variation across the range of intelligence differences. PMID:26912939

Cardiopulmonary function and oxygen delivery during total liquid ventilation.

PubMed

Tsagogiorgas, Charalambos; Alb, Markus; Herrmann, Peter; Quintel, Michael; Meinhardt, Juergen P

2011-10-01

Total liquid ventilation (TLV) with perfluorocarbons has shown to improve cardiopulmonary function in the injured and immature lung; however there remains controversy over the normal lung. Hemodynamic effects of TLV in the normal lung currently remain undetermined. This study compared changes in cardiopulmonary and circulatory function caused by either liquid or gas tidal volume ventilation. In a prospective, controlled study, 12 non-injured anesthetized, adult New Zealand rabbits were primarily conventionally gas-ventilated (CGV). After instrumentation for continuous recording of arterial (AP), central venous (CVP), left artrial (LAP), pulmonary arterial pressures (PAP), and cardiac output (CO) animals were randomized into (1) CGV group and (2) TLV group. In the TLV group partial liquid ventilation was initiated with instillation of perfluoroctylbromide (12 ml/kg). After 15 min, TLV was established for 3 hr applying a volume-controlled, pressure-limited, time-cycled ventilation mode using a double-piston configured TLV. Controls (CGV) remained gas-ventilated throughout the experiment. During TLV, heart rate, CO, PAP, MAP, CVP, and LAP as well as derived hemodynamic variables, arterial and mixed venous blood gases, oxygen delivery, PVR, and SVR did not differ significantly compared to CGV. Liquid tidal volumes suitable for long-term TLV in non-injured rabbits do not significantly impair CO, blood pressure, and oxygen dynamics when compared to CGV. Copyright © 2011 Wiley-Liss, Inc.

Examining non-syndromic autosomal recessive intellectual disability (NS-ARID) genes for an enriched association with intelligence differences.

PubMed

Hill, W D; Davies, G; Liewald, D C; Payton, A; McNeil, C J; Whalley, L J; Horan, M; Ollier, W; Starr, J M; Pendleton, N; Hansel, N K; Montgomery, G W; Medland, S E; Martin, N G; Wright, M J; Bates, T C; Deary, I J

2016-01-01

Two themes are emerging regarding the molecular genetic aetiology of intelligence. The first is that intelligence is influenced by many variants and those that are tagged by common single nucleotide polymorphisms account for around 30% of the phenotypic variation. The second, in line with other polygenic traits such as height and schizophrenia, is that these variants are not randomly distributed across the genome but cluster in genes that work together. Less clear is whether the very low range of cognitive ability (intellectual disability) is simply one end of the normal distribution describing individual differences in cognitive ability across a population. Here, we examined 40 genes with a known association with non-syndromic autosomal recessive intellectual disability (NS-ARID) to determine if they are enriched for common variants associated with the normal range of intelligence differences. The current study used the 3511 individuals of the Cognitive Ageing Genetics in England and Scotland (CAGES) consortium. In addition, a text mining analysis was used to identify gene sets biologically related to the NS-ARID set. Gene-based tests indicated that genes implicated in NS-ARID were not significantly enriched for quantitative trait loci (QTL) associated with intelligence. These findings suggest that genes in which mutations can have a large and deleterious effect on intelligence are not associated with variation across the range of intelligence differences.

The wound-healing effects of a next-generation anti-biofilm silver Hydrofiber wound dressing on deep partial-thickness wounds using a porcine model.

PubMed

Davis, Stephen C; Li, Jie; Gil, Joel; Valdes, Jose; Solis, Michael; Higa, Alex; Bowler, Philip

2018-06-11

Topical antimicrobials are widely used to control wound bioburden and facilitate wound healing; however, the fine balance between antimicrobial efficacy and non-toxicity must be achieved. This study evaluated whether an anti-biofilm silver-containing wound dressing interfered with the normal healing process in non-contaminated deep partial thickness wounds. In an in-vivo porcine wound model using 2 pigs, 96 wounds were randomly assigned to 1 of 3 dressing groups: anti-biofilm silver Hydrofiber dressing (test), silver Hydrofiber dressing (control), or polyurethane film dressing (control). Wounds were investigated for 8 days, and wound biopsies (n = 4) were taken from each dressing group, per animal, on days 2, 4, 6, and 8 after wounding and evaluated using light microscopy. No statistically significant differences were observed in the rate of reepithelialisation, white blood cell infiltration, angiogenesis, or granulation tissue formation following application of the anti-biofilm silver Hydrofiber dressing versus the 2 control dressings. Overall, epithelial thickness was similar between groups. Some differences in infiltration of specific cell types were observed between groups. There were no signs of tissue necrosis, fibrosis, or fatty infiltration in any group. An anti-biofilm silver Hydrofiber wound dressing did not cause any notable interference with normal healing processes. © 2018 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

Amygdala Reactivity to Emotional Faces in the Prediction of General and Medication-Specific Responses to Antidepressant Treatment in the Randomized iSPOT-D Trial

PubMed Central

Williams, Leanne M; Korgaonkar, Mayuresh S; Song, Yun C; Paton, Rebecca; Eagles, Sarah; Goldstein-Piekarski, Andrea; Grieve, Stuart M; Harris, Anthony W F; Usherwood, Tim; Etkin, Amit

2015-01-01

Although the cost of poor treatment outcomes of depression is staggering, we do not yet have clinically useful methods for selecting the most effective antidepressant for each depressed person. Emotional brain activation is altered in major depressive disorder (MDD) and implicated in treatment response. Identifying which aspects of emotional brain activation are predictive of general and specific responses to antidepressants may help clinicians and patients when making treatment decisions. We examined whether amygdala activation probed by emotion stimuli is a general or differential predictor of response to three commonly prescribed antidepressants, using functional magnetic resonance imaging (fMRI). A test–retest design was used to assess patients with MDD in an academic setting as part of the International Study to Predict Optimized Treatment in Depression. A total of 80 MDD outpatients were scanned prior to treatment and 8 weeks after randomization to the selective serotonin reuptake inhibitors escitalopram and sertraline and the serotonin–norepinephrine reuptake inhibitor, venlafaxine-extended release (XR). A total of 34 matched controls were scanned at the same timepoints. We quantified the blood oxygen level-dependent signal of the amygdala during subliminal and supraliminal viewing of facial expressions of emotion. Response to treatment was defined by ⩾50% symptom improvement on the 17-item Hamilton Depression Rating Scale. Pre-treatment amygdala hypo-reactivity to subliminal happy and threat was a general predictor of treatment response, regardless of medication type (Cohen's d effect size 0.63 to 0.77; classification accuracy, 75%). Responders showed hypo-reactivity compared to controls at baseline, and an increase toward ‘normalization' post-treatment. Pre-treatment amygdala reactivity to subliminal sadness was a differential moderator of non-response to venlafaxine-XR (Cohen's d effect size 1.5; classification accuracy, 81%). Non-responders to venlafaxine-XR showed pre-treatment hyper-reactivity, which progressed to hypo-reactivity rather than normalization post-treatment, and hypo-reactivity post-treatment was abnormal compared to controls. Impaired amygdala activation has not previously been highlighted in the general vs differential prediction of antidepressant outcomes. Amygdala hypo-reactivity to emotions signaling reward and threat predicts the general capacity to respond to antidepressants. Amygdala hyper-reactivity to sad emotion is involved in a specific non-response to a serotonin–norepinephrine reuptake inhibitor. The findings suggest amygdala probes may help inform the personal selection of antidepressant treatments. PMID:25824424

Designing management strategies for carbon dioxide storage and utilization under uncertainty using inexact modelling

NASA Astrophysics Data System (ADS)

Wang, Yu; Fan, Jie; Xu, Ye; Sun, Wei; Chen, Dong

2017-06-01

Effective application of carbon capture, utilization and storage (CCUS) systems could help to alleviate the influence of climate change by reducing carbon dioxide (CO2) emissions. The research objective of this study is to develop an equilibrium chance-constrained programming model with bi-random variables (ECCP model) for supporting the CCUS management system under random circumstances. The major advantage of the ECCP model is that it tackles random variables as bi-random variables with a normal distribution, where the mean values follow a normal distribution. This could avoid irrational assumptions and oversimplifications in the process of parameter design and enrich the theory of stochastic optimization. The ECCP model is solved by an equilibrium change-constrained programming algorithm, which provides convenience for decision makers to rank the solution set using the natural order of real numbers. The ECCP model is applied to a CCUS management problem, and the solutions could be useful in helping managers to design and generate rational CO2-allocation patterns under complexities and uncertainties.

Cost-effectiveness of dabigatran etexilate in the prevention of stroke and systemic embolism in patients with atrial fibrillation in Belgium.

PubMed

Wouters, Hanne; Thijs, Vincent; Annemans, Lieven

2013-01-01

To assess the cost-effectiveness of dabigatran etexilate ('dabigatran') vs vitamin K antagonists (VKAs) in the Belgian healthcare setting for the prevention of stroke and systemic embolism (SE) in patients with non-valvular atrial fibrillation (AF). A Markov model was used to calculate the cost-effectiveness of dabigatran vs VKAs in Belgium, whereby warfarin was considered representative for the VKA class. Efficacy and safety data were taken from the Randomized Evaluation of Long-Term Anticoagulation Therapy (RE-LY) trial and a network meta-analysis. Local resource use and unit costs were included in the model. Effectiveness was expressed in Quality Adjusted Life-Years (QALYs). The model outcomes were total costs, total QALYs, incremental costs, incremental QALYs and the incremental cost-effectiveness ratio (ICER). The level of International Normalized Ratio (INR) control and the use of other antithrombotic therapies observed in Belgian clinical practice were reflected in two scenario analyses. In the base case analysis, total costs per patient were €13,333 for dabigatran and €12,454 for warfarin. Total QALYs per patient were 9.51 for dabigatran and 9.19 for warfarin. The corresponding ICER was €2807/QALY. The ICER of dabigatran was €970/QALY vs warfarin with real-world INR control and €5296/QALY vs a mix of warfarin, aspirin, and no treatment. Results were shown to be robust in one-way and probabilistic sensitivity analyses. The analysis does not include long-term costs for clinical events, as these data were not available for Belgium. As in any economic model based on data from a randomized clinical trial, several assumptions had to be made when extrapolating results to routine clinical practice in Belgium. This analysis suggests that dabigatran, a novel oral anticoagulant, is a cost-effective treatment for the prevention of stroke and SE in patients with non-valvular AF in the Belgian healthcare setting.

Aberrations in uterine contractile patterns in mares with delayed uterine clearance after administration of detomidine and oxytocin.

PubMed

von Reitzenstein, Marcela; Callahan, Megan A; Hansen, Peter J; LeBlanc, Michelle M

2002-09-01

An experiment was conducted to determine whether the uterotonic effects of oxytocin, a drug used to treat mares that have a delay in uterine clearance were affected by the sedative detomidine (an alpha2-agonist), a drug used to treat fractious mares. An additional objective was to identify propagation patterns of uterine contractions and determine whether these patterns differed between normal mares and mares with delayed uterine clearance (DUC). Intrauterine pressure was measured in five reproductively normal mares and four mares with DUC during estrus using an 8-F Milar catheter with two discrete pressure sensors. Mares received one of three treatments in random order: detomidine (0.001 mg/kg; i.v.); detomidine followed in 10 min by oxytocin (10 IU; i.v.); and saline (0.9% NaCl 0.5 ml; i.v.) followed in 10 min by oxytocin. All treatments induced waves of contractions; however, only three mares with DUC exhibited contractions after administration of detomidine. Normal mares experienced more uterine contractions (P < 0.01) that tended to last longer (P < 0.06), and were of greater intensity (P < 0.04) than mares with delayed clearance. Administration of detomidine before oxytocin increased the number of contractions (P < 0.02) and increased the maximum intrauterine pressure in the uterine horn (P < 0.05) in normal mares as compared to response after administration of saline and oxytocin. Detomidine had no effect in mares with delayed clearance. All mares had more propagating than non-propagating uterine contractions (74 +/- 8 versus 25 +/- 8%, respectively). Normal mares exhibited a normal propagation pattern more frequently (P < 0.0001) than mares with DUC. Simultaneous (P < 0.05) and inverted (P < 0.03) contractions occurred more frequently in mares with DUC. Administration of detomidine increased the number (P < 0.01), and tended to increase the percentage (P < 0.07) of normal propagating uterine contractions in normal mares, but did not affect propagation patterns in mares with DUC. In conclusion, detomidine augmented the uterotonic effect of oxytocin in normal mares but not in mares with DUC. Data suggest that mares with DUC have a defect in myoelectrical signaling and a decrease in the contractile strength of the uterine muscle.

The Memory Aid study: protocol for a randomized controlled clinical trial evaluating the effect of computer-based working memory training in elderly patients with mild cognitive impairment (MCI)

PubMed Central

2014-01-01

Background Mild cognitive impairment (MCI) is a condition characterized by memory problems that are more severe than the normal cognitive changes due to aging, but less severe than dementia. Reduced working memory (WM) is regarded as one of the core symptoms of an MCI condition. Recent studies have indicated that WM can be improved through computer-based training. The objective of this study is to evaluate if WM training is effective in improving cognitive function in elderly patients with MCI, and if cognitive training induces structural changes in the white and gray matter of the brain, as assessed by structural MRI. Methods/Designs The proposed study is a blinded, randomized, controlled trail that will include 90 elderly patients diagnosed with MCI at a hospital-based memory clinic. The participants will be randomized to either a training program or a placebo version of the program. The intervention is computerized WM training performed for 45 minutes of 25 sessions over 5 weeks. The placebo version is identical in duration but is non-adaptive in the difficulty level of the tasks. Neuropsychological assessment and structural MRI will be performed before and 1 month after training, and at a 5-month folllow-up. Discussion If computer-based training results in positive changes to memory functions in patients with MCI this may represent a new, cost-effective treatment for MCI. Secondly, evaluation of any training-induced structural changes to gray or white matter will improve the current understanding of the mechanisms behind effective cognitive interventions in patients with MCI. Trial registration ClinicalTrials.gov NCT01991405. November 18, 2013. PMID:24886034

The Memory Aid study: protocol for a randomized controlled clinical trial evaluating the effect of computer-based working memory training in elderly patients with mild cognitive impairment (MCI).

PubMed

Flak, Marianne M; Hernes, Susanne S; Chang, Linda; Ernst, Thomas; Douet, Vanessa; Skranes, Jon; Løhaugen, Gro C C

2014-05-03

Mild cognitive impairment (MCI) is a condition characterized by memory problems that are more severe than the normal cognitive changes due to aging, but less severe than dementia. Reduced working memory (WM) is regarded as one of the core symptoms of an MCI condition. Recent studies have indicated that WM can be improved through computer-based training. The objective of this study is to evaluate if WM training is effective in improving cognitive function in elderly patients with MCI, and if cognitive training induces structural changes in the white and gray matter of the brain, as assessed by structural MRI. The proposed study is a blinded, randomized, controlled trail that will include 90 elderly patients diagnosed with MCI at a hospital-based memory clinic. The participants will be randomized to either a training program or a placebo version of the program. The intervention is computerized WM training performed for 45 minutes of 25 sessions over 5 weeks. The placebo version is identical in duration but is non-adaptive in the difficulty level of the tasks. Neuropsychological assessment and structural MRI will be performed before and 1 month after training, and at a 5-month folllow-up. If computer-based training results in positive changes to memory functions in patients with MCI this may represent a new, cost-effective treatment for MCI. Secondly, evaluation of any training-induced structural changes to gray or white matter will improve the current understanding of the mechanisms behind effective cognitive interventions in patients with MCI. ClinicalTrials.gov NCT01991405. November 18, 2013.

Bacteriological cure rate and changes in milk composition in mastitis vaccinated ewes affected with subclinical mastitis

PubMed Central

Alekish, Myassar O.; Ismail, Z. Bani; Hammouri, H. M.; Daradka, M. H.; Taha, S. Al; Olymat, I.

2018-01-01

Aim: The aim of this study was to investigate the effects of using a commercially-available polyvalent mastitis vaccine on the bacteriological cure rate of existing subclinical mastitis in Awassi sheep. Materials and Methods: A total of 164 lactating ewes were divided into two main groups according to udder health and milk somatic cell count (SCC): Group 1=normal (N; n=80) and Group 2=subclinical mastitis (SC; n=84). Each group was then subdivided randomly into two treatment groups: N vaccinated (Nvax; n=38), N non-vaccinated (Nnvax; n=42), SC vaccinated (SCvax; n=42), and SC non-vaccinated (SCnvax; n=42). The vaccine was administered as per manufacturer’s recommendations. Milk samples were collected aseptically from all ewes before vaccine administration (T0) and again on days 28 (T2) and 42 (T3) of the experiment. Results: In the SC group, the bacteriological cure rates in vaccinated and non-vaccinated ewes were 76% and 69%, respectively. In N group, the new intramammary infection rates in vaccinated and non-vaccinated ewes were 48% and 50%, respectively. Vaccination of normal ewes resulted in a significant (p<0.05) reduction in bacterial growth rate both at day 28 and day 42 of the study. The prevalence of new intramammary infection rate in Nvax ewes on days 28 and 42 was 19% and 20%, respectively. The prevalence of new intramammary infection rate in Nnvax group on days 28 and 42 was 33% and 30%, respectively. In SCvax group, the bacterial growth rate on days 28 and 42 was 44% and 35%, respectively. In SCnvax group, the bacterial growth rate on days 28 and 42 was 27% and 32%, respectively. There was no statistically significant effect of vaccination on any of the studied milk composition parameters. Conclusions: This is a preliminary study that indicated a possible protective effect of vaccination against mastitis in sheep. Further, case-controlled studies are indicated to estimate the level of immunity this vaccine provides to vaccinated sheep. PMID:29657391

Bacteriological cure rate and changes in milk composition in mastitis vaccinated ewes affected with subclinical mastitis.

PubMed

Alekish, Myassar O; Ismail, Z Bani; Hammouri, H M; Daradka, M H; Taha, S Al; Olymat, I

2018-02-01

The aim of this study was to investigate the effects of using a commercially-available polyvalent mastitis vaccine on the bacteriological cure rate of existing subclinical mastitis in Awassi sheep. A total of 164 lactating ewes were divided into two main groups according to udder health and milk somatic cell count (SCC): Group 1=normal (N; n=80) and Group 2=subclinical mastitis (SC; n=84). Each group was then subdivided randomly into two treatment groups: N vaccinated (N vax ; n=38), N non-vaccinated (N nvax ; n=42), SC vaccinated (SC vax ; n=42), and SC non-vaccinated (SC nvax ; n=42). The vaccine was administered as per manufacturer's recommendations. Milk samples were collected aseptically from all ewes before vaccine administration (T0) and again on days 28 (T2) and 42 (T3) of the experiment. In the SC group, the bacteriological cure rates in vaccinated and non-vaccinated ewes were 76% and 69%, respectively. In N group, the new intramammary infection rates in vaccinated and non-vaccinated ewes were 48% and 50%, respectively. Vaccination of normal ewes resulted in a significant (p<0.05) reduction in bacterial growth rate both at day 28 and day 42 of the study. The prevalence of new intramammary infection rate in N vax ewes on days 28 and 42 was 19% and 20%, respectively. The prevalence of new intramammary infection rate in N nvax group on days 28 and 42 was 33% and 30%, respectively. In SC vax group, the bacterial growth rate on days 28 and 42 was 44% and 35%, respectively. In SC nvax group, the bacterial growth rate on days 28 and 42 was 27% and 32%, respectively. There was no statistically significant effect of vaccination on any of the studied milk composition parameters. This is a preliminary study that indicated a possible protective effect of vaccination against mastitis in sheep. Further, case-controlled studies are indicated to estimate the level of immunity this vaccine provides to vaccinated sheep.

Active video games as a tool to prevent excessive weight gain in adolescents: rationale, design and methods of a randomized controlled trial.

PubMed

Simons, Monique; Chinapaw, Mai J M; van de Bovenkamp, Maaike; de Boer, Michiel R; Seidell, Jacob C; Brug, Johannes; de Vet, Emely

2014-03-24

Excessive body weight, low physical activity and excessive sedentary time in youth are major public health concerns. A new generation of video games, the ones that require physical activity to play the games--i.e. active games--may be a promising alternative to traditional non-active games to promote physical activity and reduce sedentary behaviors in youth. The aim of this manuscript is to describe the design of a study evaluating the effects of a family oriented active game intervention, incorporating several motivational elements, on anthropometrics and health behaviors in adolescents. The study is a randomized controlled trial (RCT), with non-active gaming adolescents aged 12-16 years old randomly allocated to a ten month intervention (receiving active games, as well as an encouragement to play) or a waiting-list control group (receiving active games after the intervention period). Primary outcomes are adolescents' measured BMI-SDS (SDS=adjusted for mean standard deviation score), waist circumference-SDS, hip circumference and sum of skinfolds. Secondary outcomes are adolescents' self-reported time spent playing active and non-active games, other sedentary activities and consumption of sugar-sweetened beverages. In addition, a process evaluation is conducted, assessing the sustainability of the active games, enjoyment, perceived competence, perceived barriers for active game play, game context, injuries from active game play, activity replacement and intention to continue playing the active games. This is the first adequately powered RCT including normal weight adolescents, evaluating a reasonably long period of provision of and exposure to active games. Next, strong elements are the incorporating motivational elements for active game play and a comprehensive process evaluation. This trial will provide evidence regarding the potential contribution of active games in prevention of excessive weight gain in adolescents. Dutch Trial register NTR3228.

Active video games as a tool to prevent excessive weight gain in adolescents: rationale, design and methods of a randomized controlled trial

PubMed Central

2014-01-01

Background Excessive body weight, low physical activity and excessive sedentary time in youth are major public health concerns. A new generation of video games, the ones that require physical activity to play the games –i.e. active games- may be a promising alternative to traditional non-active games to promote physical activity and reduce sedentary behaviors in youth. The aim of this manuscript is to describe the design of a study evaluating the effects of a family oriented active game intervention, incorporating several motivational elements, on anthropometrics and health behaviors in adolescents. Methods/Design The study is a randomized controlled trial (RCT), with non-active gaming adolescents aged 12 – 16 years old randomly allocated to a ten month intervention (receiving active games, as well as an encouragement to play) or a waiting-list control group (receiving active games after the intervention period). Primary outcomes are adolescents’ measured BMI-SDS (SDS = adjusted for mean standard deviation score), waist circumference-SDS, hip circumference and sum of skinfolds. Secondary outcomes are adolescents’ self-reported time spent playing active and non-active games, other sedentary activities and consumption of sugar-sweetened beverages. In addition, a process evaluation is conducted, assessing the sustainability of the active games, enjoyment, perceived competence, perceived barriers for active game play, game context, injuries from active game play, activity replacement and intention to continue playing the active games. Discussion This is the first adequately powered RCT including normal weight adolescents, evaluating a reasonably long period of provision of and exposure to active games. Next, strong elements are the incorporating motivational elements for active game play and a comprehensive process evaluation. This trial will provide evidence regarding the potential contribution of active games in prevention of excessive weight gain in adolescents. Trial registration Dutch Trial register NTR3228. PMID:24661535

[Effect of polysaccharides in processed Sibiraea on immunologic function of immunosuppression mice].

PubMed

Duan, Bowen; Li, Yun; Liu, Xin; Yang, Yongjian

2010-06-01

To study the effect of polysaccharides in processed Sibiraea on the immunologic function of immunosuppression mice. The immunosuppressed mice were induced by cyclophosphamide. After the treatment, the organ weight index and the delayed type hypersensitivity of the mice were investigated. The humoral immune function was determined by serum hemolysin assay. Non-specific immune function was determined by carbon clearance method. Cellular immune function was determined by spleen lymphocyte proliferation test. Two hundred kunming mice were randomly divided into five groups: normal controls, model group, low-dose group (110 mg x kg(-1)), middle-dose group (220 mg x kg(-1)), high-dose group (440 mg x kg(-1)). Drugs were given to the mice by oral gavage every day. The immunosuppressed mice treated with Sibiraea polysibcharide at intragastrica dose of 110-440 mg x kg(-1) have increased weight of the immune organs, increased content of DTH and content in serum hemolysin lgG and lgM. Mean while the rate of carbon clearance was enhanced and the proliferation of spleen lymphocyte was increased. Polysaccharides in processed Sibiraea can increase the weight of the immune organs. At the same time, non-specific immune, DTH, humoral immune and cellular immune function were enhanced significantly.

Preference option randomized design (PORD) for comparative effectiveness research: Statistical power for testing comparative effect, preference effect, selection effect, intent-to-treat effect, and overall effect.

PubMed

Heo, Moonseong; Meissner, Paul; Litwin, Alain H; Arnsten, Julia H; McKee, M Diane; Karasz, Alison; McKinley, Paula; Rehm, Colin D; Chambers, Earle C; Yeh, Ming-Chin; Wylie-Rosett, Judith

2017-01-01

Comparative effectiveness research trials in real-world settings may require participants to choose between preferred intervention options. A randomized clinical trial with parallel experimental and control arms is straightforward and regarded as a gold standard design, but by design it forces and anticipates the participants to comply with a randomly assigned intervention regardless of their preference. Therefore, the randomized clinical trial may impose impractical limitations when planning comparative effectiveness research trials. To accommodate participants' preference if they are expressed, and to maintain randomization, we propose an alternative design that allows participants' preference after randomization, which we call a "preference option randomized design (PORD)". In contrast to other preference designs, which ask whether or not participants consent to the assigned intervention after randomization, the crucial feature of preference option randomized design is its unique informed consent process before randomization. Specifically, the preference option randomized design consent process informs participants that they can opt out and switch to the other intervention only if after randomization they actively express the desire to do so. Participants who do not independently express explicit alternate preference or assent to the randomly assigned intervention are considered to not have an alternate preference. In sum, preference option randomized design intends to maximize retention, minimize possibility of forced assignment for any participants, and to maintain randomization by allowing participants with no or equal preference to represent random assignments. This design scheme enables to define five effects that are interconnected with each other through common design parameters-comparative, preference, selection, intent-to-treat, and overall/as-treated-to collectively guide decision making between interventions. Statistical power functions for testing all these effects are derived, and simulations verified the validity of the power functions under normal and binomial distributions.

Added sugars and risk factors for obesity, diabetes and heart disease.

PubMed

Rippe, J M; Angelopoulos, T J

2016-03-01

The effects of added sugars on various chronic conditions are highly controversial. Some investigators have argued that added sugars increase the risk of obesity, diabetes and cardiovascular disease. However, few randomized controlled trials are available to support these assertions. The literature is further complicated by animal studies, as well as studies which compare pure fructose to pure glucose (neither of which is consumed to any appreciable degree in the human diet) and studies where large doses of added sugars beyond normal levels of human consumption have been administered. Various scientific and public health organizations have offered disparate recommendations for upper limits of added sugar. In this article, we will review recent randomized controlled trials and prospective cohort studies. We conclude that the normal added sugars in the human diet (for example, sucrose, high-fructose corn syrup and isoglucose) when consumed within the normal range of normal human consumption or substituted isoenergetically for other carbohydrates, do not appear to cause a unique risk of obesity, diabetes or cardiovascular disease.

Plasma fat-soluble vitamin and carotenoid concentrations after plant sterol and plant stanol consumption: a meta-analysis of randomized controlled trials.

PubMed

Baumgartner, Sabine; Ras, Rouyanne T; Trautwein, Elke A; Mensink, Ronald P; Plat, Jogchum

2017-04-01

Plant sterols and stanols interfere with intestinal cholesterol absorption, and it has been questioned whether absorption and plasma concentrations of fat-soluble vitamins and carotenoids are also affected. We conducted a meta-analysis to assess the effects of plant sterol and stanol consumption on plasma fat-soluble vitamin and carotenoid concentrations. Forty-one randomized controlled trials involving 3306 subjects were included. Weighted absolute and relative changes of non-standardized and total cholesterol (TC)-standardized values (expressed as summary estimates and 95 % CIs) were calculated for three fat-soluble vitamins (α- and γ-tocopherol, retinol and vitamin D) and six carotenoids (β-carotene, α-carotene, lycopene, lutein, zeaxanthin and β-cryptoxanthin) using a random effects model. Heterogeneity was assessed using predefined subject and treatment characteristics. Average plant sterol or stanol intake was 2.5 g/d. Relative non-standardized and TC-standardized concentrations of β-carotene decreased by, respectively, -16.3 % (95 % CI -18.3; -14.3) and -10.1 % (-12.3; -8.0), α-carotene by -14.4 % (-17.5; 11.3) and -7.8 % (-11.3; -4.3), and lycopene by -12.3 % (-14.6; -10.1) and -6.3 % (-8.6; -4.0). Lutein concentrations decreased by -7.4 % (-10.1; -4.8), while TC-standardized concentrations were not changed. For zeaxanthin, these values were -12.9 % (-18.9; -6.8) and -7.7 % (-13.8; -1.7) and for β-cryptoxanthin -10.6 % (-14.3; -6.9) and -4.8 % (-8.7; -0.9). Non-standardized α-tocopherol concentrations decreased by -7.1 % (-8.0; -6.2) and γ-tocopherol by -6.9 % (-9.8; -3.9), while TC-standardized tocopherol concentrations were not changed. Non-standardized retinol and vitamin D concentrations were not affected. Results were not affected by baseline concentrations, dose, duration and type of plant sterols/stanols, except for significant effects of duration (≤4 vs. >4 weeks) on TC-standardized lutein concentrations (1.0 vs. -5.6 %) and type of plant sterol/stanol on TC-standardized β-carotene concentrations (-8.9 vs. -14.2 %). Plant sterol and stanol intake lowers TC-standardized hydrocarbon carotenoid concentrations, differently affects TC-standardized oxygenated carotenoid concentrations, but does not affect TC-standardized tocopherol concentrations or absolute retinol and vitamin D concentrations. Observed concentrations remained within normal ranges.

Non-ignorable missingness item response theory models for choice effects in examinee-selected items.

PubMed

Liu, Chen-Wei; Wang, Wen-Chung

2017-11-01

Examinee-selected item (ESI) design, in which examinees are required to respond to a fixed number of items in a given set, always yields incomplete data (i.e., when only the selected items are answered, data are missing for the others) that are likely non-ignorable in likelihood inference. Standard item response theory (IRT) models become infeasible when ESI data are missing not at random (MNAR). To solve this problem, the authors propose a two-dimensional IRT model that posits one unidimensional IRT model for observed data and another for nominal selection patterns. The two latent variables are assumed to follow a bivariate normal distribution. In this study, the mirt freeware package was adopted to estimate parameters. The authors conduct an experiment to demonstrate that ESI data are often non-ignorable and to determine how to apply the new model to the data collected. Two follow-up simulation studies are conducted to assess the parameter recovery of the new model and the consequences for parameter estimation of ignoring MNAR data. The results of the two simulation studies indicate good parameter recovery of the new model and poor parameter recovery when non-ignorable missing data were mistakenly treated as ignorable. © 2017 The British Psychological Society.

Effect of restricted protein diet supplemented with keto analogues in chronic kidney disease: a systematic review and meta-analysis.

PubMed

Jiang, Zheng; Zhang, Xiaoyan; Yang, Lichuan; Li, Zi; Qin, Wei

2016-03-01

To evaluate the efficacy and safety of the restricted protein diet (low or very low protein diet) supplemented with keto analogues in the treatment of chronic kidney disease (CKD). The Cochrane library, PubMed, Embase, CBM and CENTRAL databases were searched and reviewed up to April 2015. Clinical trials were analyzed using RevMan 5.3 software. Seven random control trials, one cross-over trial and one non-randomized concurrent control trial were selected and included in this study according to our inclusion and exclusion criteria. The changes of eGFR, BUN, Scr, albumin, PTH, triglyceride, cholesterol, calcium, phosphorus and nutrition indexes (BMI, lean body mass and mid-arm muscular circumference) before and after treatment were analyzed. The meta-analysis results indicated that, comparing with normal protein diet, low protein diet (LPD) or very low protein diet (vLPD) supplemented with keto analogues (s(v)LPD) could significantly prevent the deterioration of eGFR (P < 0.001), hyperparathyroidism (P = 0.04), hypertension (P < 0.01) and hyperphosphatemia (P < 0.001). No differences in BUN, Scr, Albumin, triglyceride, cholesterol, hemoglobin, calcium and nutrition indexes were observed between different protein intake groups. Restricted protein diet supplemented with keto analogues (s(v)LPD) could delay the progression of CKD effectively without causing malnutrition.

Fast selection of miRNA candidates based on large-scale pre-computed MFE sets of randomized sequences

PubMed Central

2014-01-01

Background Small RNAs are important regulators of genome function, yet their prediction in genomes is still a major computational challenge. Statistical analyses of pre-miRNA sequences indicated that their 2D structure tends to have a minimal free energy (MFE) significantly lower than MFE values of equivalently randomized sequences with the same nucleotide composition, in contrast to other classes of non-coding RNA. The computation of many MFEs is, however, too intensive to allow for genome-wide screenings. Results Using a local grid infrastructure, MFE distributions of random sequences were pre-calculated on a large scale. These distributions follow a normal distribution and can be used to determine the MFE distribution for any given sequence composition by interpolation. It allows on-the-fly calculation of the normal distribution for any candidate sequence composition. Conclusion The speedup achieved makes genome-wide screening with this characteristic of a pre-miRNA sequence practical. Although this particular property alone will not be able to distinguish miRNAs from other sequences sufficiently discriminative, the MFE-based P-value should be added to the parameters of choice to be included in the selection of potential miRNA candidates for experimental verification. PMID:24418292

Effects of Parsley (Petroselinum crispum) and its Flavonol Constituents, Kaempferol and Quercetin, on Serum Uric Acid Levels, Biomarkers of Oxidative Stress and Liver Xanthine Oxidoreductase Aactivity inOxonate-Induced Hyperuricemic Rats.

PubMed

Haidari, Fatemeh; Keshavarz, Seid Ali; Mohammad Shahi, Majid; Mahboob, Soltan-Ali; Rashidi, Mohammad-Reza

2011-01-01

Increased serum uric acid is known to be a major risk related to the development of several oxidative stress diseases. The aim of this study was to investigate the effect of parsley, quercetin and kaempferol on serum uric acid levels, liver xanthine oxidoreductase activity and two non-invasive biomarkers of oxidative stress (total antioxidant capacity and malondialdehyde concentration) in normal and oxonate-induced hyperuricemic rats. A total of 60 male Wistar rats were randomly divided into ten equal groups; including 5 normal groups (vehicle, parsley, quercetin, kaempferol and allopurinol) and 5 hyperuricemic groups (vehicle, parsley, quercetin, kaempferol and allopurinol). Parsley (5 g/Kg), quercetin (5 mg/Kg), kaempferol (5 mg/Kg) and allopurinol (5 mg/Kg) were administrated to the corresponding groups by oral gavage once a day for 2 weeks. The results showed that parsley and its flavonol did not cause any significant reduction in the serum uric acid levels in normal rats, but significantly reduced the serum uric acid levels of hyperuricemic rats in a time-dependent manner. All treatments significantly inhibited liver xanthine oxidoreductase activity. Parsley, kaempferol and quercetin treatment led also to a significant increase in total antioxidant capacity and decrease in malondialdehyde concentration in hyperuricemic rats. Although the hypouricemic effect of allopurinol was much higher than that of parsley and its flavonol constituents, it could not significantly change oxidative stress biomarkers. These features of parsley and its flavonols make them as a possible alternative for allopurinol, or at least in combination therapy to minimize the side effects of allopurinol to treat hyperuricemia and oxidative stress diseases.

Effects of Parsley (Petroselinum crispum) and its Flavonol Constituents, Kaempferol and Quercetin, on Serum Uric Acid Levels, Biomarkers of Oxidative Stress and Liver Xanthine Oxidoreductase Aactivity inOxonate-Induced Hyperuricemic Rats

PubMed Central

Haidari, Fatemeh; Keshavarz, Seid Ali; Mohammad Shahi, Majid; Mahboob, Soltan-Ali; Rashidi, Mohammad-Reza

2011-01-01

Increased serum uric acid is known to be a major risk related to the development of several oxidative stress diseases. The aim of this study was to investigate the effect of parsley, quercetin and kaempferol on serum uric acid levels, liver xanthine oxidoreductase activity and two non-invasive biomarkers of oxidative stress (total antioxidant capacity and malondialdehyde concentration) in normal and oxonate-induced hyperuricemic rats. A total of 60 male Wistar rats were randomly divided into ten equal groups; including 5 normal groups (vehicle, parsley, quercetin, kaempferol and allopurinol) and 5 hyperuricemic groups (vehicle, parsley, quercetin, kaempferol and allopurinol). Parsley (5 g/Kg), quercetin (5 mg/Kg), kaempferol (5 mg/Kg) and allopurinol (5 mg/Kg) were administrated to the corresponding groups by oral gavage once a day for 2 weeks. The results showed that parsley and its flavonol did not cause any significant reduction in the serum uric acid levels in normal rats, but significantly reduced the serum uric acid levels of hyperuricemic rats in a time-dependent manner. All treatments significantly inhibited liver xanthine oxidoreductase activity. Parsley, kaempferol and quercetin treatment led also to a significant increase in total antioxidant capacity and decrease in malondialdehyde concentration in hyperuricemic rats. Although the hypouricemic effect of allopurinol was much higher than that of parsley and its flavonol constituents, it could not significantly change oxidative stress biomarkers. These features of parsley and its flavonols make them as a possible alternative for allopurinol, or at least in combination therapy to minimize the side effects of allopurinol to treat hyperuricemia and oxidative stress diseases. PMID:24250417

Ayurvedic interventions for osteoarthritis: a systematic review and meta-analysis.

PubMed

Kessler, Christian S; Pinders, Lea; Michalsen, Andreas; Cramer, Holger

2015-02-01

Ayurveda is one of the fastest growing systems within complementary and alternative medicine. However, the evidence for its effectiveness is unsatisfactory. The aim of this work was to review and meta-analyze the effectiveness and safety of different Ayurvedic interventions in patients with osteoarthritis (OA). 138 electronic databases were searched through August 2013. Randomized controlled trials, randomized crossover studies, cluster-randomized trials, and non-randomized controlled clinical trials were eligible. Adults with pre-diagnosed OA were included as participants. Interventions were included as Ayurvedic if they were explicitly labeled as such. Main outcome measures were pain, physical function, and global improvement. Risk of bias was assessed using the Cochrane risk of bias tool. 19 randomized and 14 non-randomized controlled trials on 12 different drugs and 3 non-pharmaceutical interventions with a total of 2,952 patients were included. For the compound preparation, Rumalaya, large and apparently unbiased effects beyond placebo were found for pain (standardized mean difference [SMD] -3.73; 95 % confidence interval [CI] -4.97, -2.50; P < 0.01) and global improvement (risk ratio 12.20; 95 % CI 5.83, 25.54; P < 0.01). There is also some evidence that effects of the herbal compound preparation Shunti-Guduchi are comparable to those of glucosamine for pain (SMD 0.08; 95 % CI -0.20, 0.36; P = 0.56) and function (SMD 0.15; 95 % CI -0.12, 0.36; P = 0.41). Based on single trials, positive effects were found for the compound preparations RA-11, Reosto, and Siriraj Wattana. For Boswellia serrata, Lepidium Sativum, a Boswellia serrata containing multicomponent formulation and the compounds Nirgundi Taila, Panchatikta Ghrita Guggulu, and Rhumayog, and for non-pharmacological interventions like Ayurvedic massage, steam therapy, and enema, no evidence for significant effects against potential methodological bias was found. No severe adverse events were observed in all trials. The drugs Rumalaya and Shunti-Guduchi seem to be safe and effective drugs for treatment of OA-patients, based on these data. However, several limitations relate to clinical research on Ayurveda. Well-planned, well-conducted and well-published trials are warranted to improve the evidence for Ayurvedic interventions.

Mixture model normalization for non-targeted gas chromatography/mass spectrometry metabolomics data.

PubMed

Reisetter, Anna C; Muehlbauer, Michael J; Bain, James R; Nodzenski, Michael; Stevens, Robert D; Ilkayeva, Olga; Metzger, Boyd E; Newgard, Christopher B; Lowe, William L; Scholtens, Denise M

2017-02-02

Metabolomics offers a unique integrative perspective for health research, reflecting genetic and environmental contributions to disease-related phenotypes. Identifying robust associations in population-based or large-scale clinical studies demands large numbers of subjects and therefore sample batching for gas-chromatography/mass spectrometry (GC/MS) non-targeted assays. When run over weeks or months, technical noise due to batch and run-order threatens data interpretability. Application of existing normalization methods to metabolomics is challenged by unsatisfied modeling assumptions and, notably, failure to address batch-specific truncation of low abundance compounds. To curtail technical noise and make GC/MS metabolomics data amenable to analyses describing biologically relevant variability, we propose mixture model normalization (mixnorm) that accommodates truncated data and estimates per-metabolite batch and run-order effects using quality control samples. Mixnorm outperforms other approaches across many metrics, including improved correlation of non-targeted and targeted measurements and superior performance when metabolite detectability varies according to batch. For some metrics, particularly when truncation is less frequent for a metabolite, mean centering and median scaling demonstrate comparable performance to mixnorm. When quality control samples are systematically included in batches, mixnorm is uniquely suited to normalizing non-targeted GC/MS metabolomics data due to explicit accommodation of batch effects, run order and varying thresholds of detectability. Especially in large-scale studies, normalization is crucial for drawing accurate conclusions from non-targeted GC/MS metabolomics data.

Myocardial Fibrosis Progression in Duchenne and Becker Muscular Dystrophy: A Randomized Clinical Trial.

PubMed

Silva, Marly Conceição; Magalhães, Tiago Augusto; Meira, Zilda Maria Alves; Rassi, Carlos Henrique Reis Esselin; Andrade, Amanda Cristina de Souza; Gutierrez, Paulo Sampaio; Azevedo, Clerio Francisco; Gurgel-Giannetti, Juliana; Vainzof, Mariz; Zatz, Mayana; Kalil-Filho, Roberto; Rochitte, Carlos Eduardo

2017-02-01

In Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD), interventions reducing the progression of myocardial disease could affect survival. To assess the effect of early angiotensin-converting enzyme (ACE) inhibitor therapy in patients with normal left ventricular function on the progression of myocardial fibrosis (MF) identified on cardiovascular magnetic resonance (CMR). A randomized clinical trial conducted in 2 centers included 76 male patients with DMD or BMD undergoing 2 CMR studies with a 2-year interval for ventricular function and MF assessment. In a non-intent-to-treat trial, 42 patients with MF and normal left ventricular ejection fraction (LVEF) were randomized (1:1) to receive or not receive ACE inhibitor therapy. The study was conducted from June 26, 2009, to June 30, 2012. Data analysis was performed from June 30, 2013, to October 3, 2016. Randomization (1:1) to receive or not receive ACE inhibitor therapy. Primary outcome was MF progression from baseline to the 2-year CMR study. Of the 76 male patients included in the study, 70 had DMD (92%) and 6 had BMD (8%); mean (SD) age at baseline was 13.1 (4.4) years. Myocardial fibrosis was present in 55 patients (72%) and LV systolic dysfunction was identified in 13 patients (24%). Myocardial fibrosis at baseline was an independent indicator of lower LVEF at follow-up (coefficient [SE], -0.16 [0.07]; P = .03). Among patients with MF and preserved LVEF (42 [55%]), those randomized (21 patients in each arm) to receive ACE inhibitors demonstrated slower MF progression compared with the untreated group (mean [SD] increase of 3.1% [7.4%] vs 10.0% [6.2%] as a percentage of LV mass; P = .001). In multivariate analysis, ACE inhibitor therapy was an independent indicator of decreased MF progression (coefficient [SE], -4.51 [2.11]; P = .04). Patients with MF noted on CMR had a higher probability of cardiovascular events (event rate, 10 of 55 [18.2%] vs 0 of 21 [0%]; log-rank P = .04). In this 2-year, follow-up, randomized clinical trial of patients with Duchenne or Becker muscular dystrophy whose LVEF was preserved and MF was present as determined on CMR, ACE inhibitor therapy was associated with significantly slower progression of MF. The presence of MF was associated with worse patient prognosis. clinicaltrials.org Identifier: NCT02432885.

Effects of lifestyle intervention on dietary intake, physical activity level, and gestational weight gain in pregnant women with different pre-pregnancy Body Mass Index in a randomized control trial.

PubMed

Hui, Amy Leung; Back, Lisa; Ludwig, Sora; Gardiner, Phillip; Sevenhuysen, Gustaaf; Dean, Heather J; Sellers, Elisabeth; McGavock, Jonathan; Morris, Margaret; Jiang, Depeng; Shen, Garry X

2014-09-24

The objectives of this study were to assess the efficacy of lifestyle intervention on gestational weight gain in pregnant women with normal and above normal body mass index (BMI) in a randomized controlled trial. A total of 116 pregnant women (<20 weeks of pregnancy) without diabetes were enrolled and 113 pregnant women completed the program. Participants were randomized into intervention and control groups. Women in the intervention group received weekly trainer-led group exercise sessions, instructed home exercise for 3-5-times/week during 20-36 weeks of gestation, and dietary counseling twice during pregnancy. Participants in the control group did not receive the intervention. All participants completed a physical activity questionnaire and a 3-day food record at enrolment and 2 months after enrolment. The participants in the intervention group with normal pre-pregnancy BMI (≤24.9 kg/M2, n = 30) had lower gestational weight gain (GWG), offspring birth weight and excessive gestational weight gain (EGWG) on pregnancy weight gain compared to the control group (n = 27, p < 0.05). Those weight related-changes were not detected between the intervention (n = 27) and control group (n = 29) in the above normal pre-pregnancy BMI participants. Intervention reduced total calorie, total fat, saturated fat and cholesterol intake were detected in women with normal or above normal pre-pregnancy BMI compared to the control group (p < 0.05 or 0.01). Increased physical activity and reduced carbohydrate intake were detected in women with normal (p < 0.05), but not above normal, pre-pregnancy BMI at 2 months after the onset of the intervention compared to the control group. The results of the present study demonstrated that the lifestyle intervention program decreased EGWG, GWG, offspring birth weight in pregnant women with normal, but not above normal, pre-pregnancy BMI, which was associated with increased physical activity and decreased carbohydrate intake. NCT00486629.

Distributional assumptions in food and feed commodities- development of fit-for-purpose sampling protocols.

PubMed

Paoletti, Claudia; Esbensen, Kim H

2015-01-01

Material heterogeneity influences the effectiveness of sampling procedures. Most sampling guidelines used for assessment of food and/or feed commodities are based on classical statistical distribution requirements, the normal, binomial, and Poisson distributions-and almost universally rely on the assumption of randomness. However, this is unrealistic. The scientific food and feed community recognizes a strong preponderance of non random distribution within commodity lots, which should be a more realistic prerequisite for definition of effective sampling protocols. Nevertheless, these heterogeneity issues are overlooked as the prime focus is often placed only on financial, time, equipment, and personnel constraints instead of mandating acquisition of documented representative samples under realistic heterogeneity conditions. This study shows how the principles promulgated in the Theory of Sampling (TOS) and practically tested over 60 years provide an effective framework for dealing with the complete set of adverse aspects of both compositional and distributional heterogeneity (material sampling errors), as well as with the errors incurred by the sampling process itself. The results of an empirical European Union study on genetically modified soybean heterogeneity, Kernel Lot Distribution Assessment are summarized, as they have a strong bearing on the issue of proper sampling protocol development. TOS principles apply universally in the food and feed realm and must therefore be considered the only basis for development of valid sampling protocols free from distributional constraints.

Intermittent slow sand filtration for preventing diarrhoea among children in Kenyan households using unimproved water sources: randomized controlled trial.

PubMed

Tiwari, Sangya-Sangam K; Schmidt, Wolf-Peter; Darby, Jeannie; Kariuki, Z G; Jenkins, Marion W

2009-11-01

Measure effectiveness of intermittent slow sand filtration for reducing child diarrhoea among households using unimproved water sources in rural Kenya. A randomized controlled trail was conducted among populations meeting a high-risk profile for child diarrhoea from drinking river water in the River Njoro watershed. Intervention households (30) were provided the concrete BioSand Filter and instructed on filter use and maintenance. Control households (29) continued normal practices. Longitudinal monthly monitoring of diarrhoea (seven-day daily prevalence recall) and of influent, effluent, and drinking water quality for fecal coliform was conducted for 6 months. Intervention households had better drinking water quality than control households (fecal coliform geometric mean, 30.0 CFU vs. 89.0 CFU/100 ml, P < 0.001) and reported significantly fewer diarrhoea days (86 days over 626 child-weeks) compared to controls (203 days over 558 child-weeks) among children up to 15 (age-adjusted RR 0.46; 95 % CI = 0.22, 0.96). Greater child diarrhoea reduction due to the intervention (age-adjusted RR 0.23, 95 % CI = 0.10, 0.51) was observed among the sub-group using unimproved water sources all of the time. Intermittent slow sand filtration, a non-commercial technology, produces similar observed effects on child diarrhoea as commercial POU products, adding to the range of effective options for poor populations (chlorination, ceramic filtration, solar disinfection, flocculation/disinfection).

Randomized, controlled clinical trial to evaluate a xenogeneic collagen matrix as an alternative to free gingival grafting for oral soft tissue augmentation.

PubMed

McGuire, Michael K; Scheyer, E Todd

2014-10-01

The standard of care for increasing keratinized tissue (KT) and vestibular area is an autogenous free gingival graft (FGG) and vestibuloplasty; however, there is morbidity associated with the harvest of autogenous tissue, and supply is limited. The purpose of this study is to determine if a xenogeneic collagen matrix (CM) might be as effective as FGG. This study is a single-masked, randomized, controlled, split-mouth study of 30 patients with insufficient zones of KT (<2 mm). It uses a within-patient treatment-comparison design to establish non-inferiority of the test (CM) versus control (FGG) therapy. The primary efficacy endpoint was change in KT width (∆KT) from surgery to 6 months post-surgery. Secondary endpoints included traditional periodontal measures, such as clinical attachment level, recession, and bleeding on probing. Patient-reported pain, discomfort, and esthetic satisfaction were also recorded. Biopsies were obtained at 6 months. Surgery and postoperative sequelae were uneventful, with normal healing observed at both test and control sites. The primary outcome, ∆KT width at 6 months, did not establish non-inferiority of CM compared to FGG (P = 0.9992), with the FGG sites averaging 1.5 mm more KT width than CM sites. However, the amount of new KT generated for both therapies averaged ≥2 mm. Secondary outcomes were not significantly different between test and control sites. All site biopsies appeared as normal mucoperiosteum with keratinized epithelium. CM sites achieved better texture and color matches, and more than two-thirds of patients preferred the appearance of their CM sites. With the proviso of sufficient KT (≈2 mm in width) and study goals of lower morbidity, unlimited supply, and patient satisfaction, CM appears to be a suitable substitute for FGG in vestibuloplasty procedures designed to increase KT around teeth.

Transmittance of transparent windows with non-absorbing cap-shaped droplets condensed on their backside

NASA Astrophysics Data System (ADS)

Zhu, Keyong; Huang, Yong; Pruvost, Jeremy; Legrand, Jack; Pilon, Laurent

2017-06-01

This study aims to quantify systematically the effect of non-absorbing cap-shaped droplets condensed on the backside of transparent windows on their directional-hemispherical transmittance and reflectance. Condensed water droplets have been blamed to reduce light transfer through windows in greenhouses, solar desalination plants, and photobioreactors. Here, the directional-hemispherical transmittance was predicted by Monte Carlo ray-tracing method. For the first time, both monodisperse and polydisperse droplets were considered, with contact angle between 0 and 180°, arranged either in an ordered hexagonal pattern or randomly distributed on the window backside with projected surface area coverage between 0 and 90%. The directional-hemispherical transmittance was found to be independent of the size and spatial distributions of the droplets. Instead, it depended on (i) the incident angle, (ii) the optical properties of the window and droplets, and on (iii) the droplet contact angle and (iv) projected surface area coverage. In fact, the directional-hemispherical transmittance decreased with increasing incident angle. Four optical regimes were identified in the normal-hemispherical transmittance. It was nearly constant for droplet contact angles either smaller than the critical angle θcr (predicted by Snell's law) for total internal reflection at the droplet/air interface or larger than 180°-θcr. However, between these critical contact angles, the normal-hemispherical transmittance decreased rapidly to reach a minimum at 90° and increased rapidly with increasing contact angles up to 180°-θcr. This was attributed to total internal reflection at the droplet/air interface which led to increasing reflectance. In addition, the normal-hemispherical transmittance increased slightly with increasing projected surface area coverage for contact angle was smaller than θcr. However, it decreased monotonously with increasing droplet projected surface area coverage for contact angle larger than θcr. These results can be used to select the material or surface coating with advantageous surface properties for applications when dropwise condensation may otherwise have a negative effect on light transmittance.

Longitudinal data analysis with non-ignorable missing data.

PubMed

Tseng, Chi-hong; Elashoff, Robert; Li, Ning; Li, Gang

2016-02-01

A common problem in the longitudinal data analysis is the missing data problem. Two types of missing patterns are generally considered in statistical literature: monotone and non-monotone missing data. Nonmonotone missing data occur when study participants intermittently miss scheduled visits, while monotone missing data can be from discontinued participation, loss to follow-up, and mortality. Although many novel statistical approaches have been developed to handle missing data in recent years, few methods are available to provide inferences to handle both types of missing data simultaneously. In this article, a latent random effects model is proposed to analyze longitudinal outcomes with both monotone and non-monotone missingness in the context of missing not at random. Another significant contribution of this article is to propose a new computational algorithm for latent random effects models. To reduce the computational burden of high-dimensional integration problem in latent random effects models, we develop a new computational algorithm that uses a new adaptive quadrature approach in conjunction with the Taylor series approximation for the likelihood function to simplify the E-step computation in the expectation-maximization algorithm. Simulation study is performed and the data from the scleroderma lung study are used to demonstrate the effectiveness of this method. © The Author(s) 2012.

Stone former urine proteome demonstrates a cationic shift in protein distribution compared to normal.

PubMed

Kolbach-Mandel, Ann M; Mandel, Neil S; Hoffmann, Brian R; Kleinman, Jack G; Wesson, Jeffrey A

2017-08-01

Many urine proteins are found in calcium oxalate stones, yet decades of research have failed to define the role of urine proteins in stone formation. This urine proteomic study compares the relative amounts of abundant urine proteins between idiopathic calcium oxalate stone forming and non-stone forming (normal) cohorts to identify differences that might correlate with disease. Random mid-morning urine samples were collected following informed consent from 25 stone formers and 14 normal individuals. Proteins were isolated from urine using ultrafiltration. Urine proteomes for each sample were characterized using label-free spectral counting mass spectrometry, so that urine protein relative abundances could be compared between the two populations. A total of 407 unique proteins were identified with the 38 predominant proteins accounting for >82% of all sample spectral counts. The most highly abundant proteins were equivalent in stone formers and normals, though significant differences were observed in a few moderate abundance proteins (immunoglobulins, transferrin, and epidermal growth factor), accounting for 13 and 10% of the spectral counts, respectively. These proteins contributed to a cationic shift in protein distribution in stone formers compared to normals (22% vs. 18%, p = 0.04). Our data showing only small differences in moderate abundance proteins suggest that no single protein controls stone formation. Observed increases in immunoglobulins and transferrin suggest increased inflammatory activity in stone formers, but cannot distinguish cause from effect in stone formation. The observed cationic shift in protein distribution would diminish protein charge stabilization, which could lead to protein aggregation and increased risk for crystal aggregation.

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

PubMed

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.

Whether Visual Information Loss of Expression by Community Pharmacist Masks to Effect a Change in Feeling of Trust among Help-seeker?

PubMed

Kishimoto, Keiko; Hasaka, Akiko; Yamaura, Katsunori; Fukushima, Noriko

2016-01-01

Pharmacy is required to shift toward human service such as hearing the complaints of health. But the study about help-seeking behavior to pharmacist is not really investigated. We hypothesized that a decrease in expression visibility, due to pharmacists' typical masks, may negatively impact help-seeker' trust in pharmacist. The sample included 100 drugstore customers aged ≥18 years. Participants were stratified by gender and randomly assigned to two groups: evaluation of clear-masked and normal-masked pharmacists. After viewing a video with either male or female pharmacists wearing either clear or normal masks, participants completed a questionnaire. The primary outcome was trust in pharmacist measured by the Trust Scale and the secondary outcome was impression of the pharmacist measured by nineteen pairs of adjectives. There were no differences by gender on trust scores. Results revealed that both male and female pharmacists who wore clear masks were rated as more trustworthy than normal-masked pharmacists (p<0.001, d=0.903, and p=0.001, d=0.716, respectively). Sixteen of nineteen adjectives reported for pharmacists wearing normal masks indicated greater negative intention than those with clear masks (d=0.431-1.469). In most cases, among pharmacists wearing clear masks, results showed positive correlations between trust and each impression adjective (r=0.279-0.710). Our findings indicate that pharmacists wearing normal masks, which partially hide facial expressions, may decrease customer's trust in pharmacist. Further, normal masks were associated with negative impression. To avoid the inhibition of help-seek behavior, we recommend that pharmacists wear a clear mask and increase non-verbal communication.

HIGHER SERUM TOTAL CHOLESTEROL LEVELS IN LATE MIDDLE AGE ARE ASSOCIATED WITH GLUCOSE HYPOMETABOLISM IN BRAIN REGIONS AFFECTED BY ALZHEIMER’S DISEASE AND NORMAL AGING

PubMed Central

Reiman, Eric M.; Chen, Kewei; Langbaum, Jessica B.S.; Lee, Wendy; Reschke, Cole; Bandy, Daniel; Alexander, Gene E.; Caselli, Richard J.

2010-01-01

Epidemiological studies suggest that higher midlife serum total cholesterol levels are associated with an increased risk of Alzheimer’s disease (AD). Using fluorodeoxyglucose positron emission tomography (PET) in the study of cognitively normal late-middle-aged people, we demonstrated an association between apolipoprotein E (APOE) ε4 gene dose, the major genetic risk factor for late-onset AD, and lower measurements of the cerebral metabolic rate for glucose (CMRgl) in AD-affected brain regions, we proposed using PET as a presymptomatic endophenotype to evaluate other putative AD risk modifiers, and we then used it to support an aggregate cholesterol-related genetic risk score in the risk of AD. In the present study, we used PET to investigate the association between serum total cholesterol levels and cerebral metabolic rate for glucose metabolism (CMRgl) in 117 cognitively normal late middle-aged APOE ε4 homozygotes, heterozygotes and noncarriers. Higher serum total cholesterol levels were associated with lower CMRgl bilaterally in precuneus, parietotemporal and prefrontal regions previously found to be preferentially affected by AD, and in additional frontal regions previously found to be preferentially affected by normal aging. The associations were greater in APOE ε4 carriers than non-carriers in some of the AD-affected brain regions. We postulate the higher midlife serum total cholesterol levels accelerate brain processes associated with normal aging and conspire with other risk factors in the predisposition to AD. We propose using PET in proof-of-concept randomized controlled trials to rapidly evaluate the effects of midlife cholesterol-lowering treatments on the brain changes associated with normal aging and AD. PMID:19631758

A new mosaic method for three-dimensional surface

NASA Astrophysics Data System (ADS)

Yuan, Yun; Zhu, Zhaokun; Ding, Yongjun

2011-08-01

Three-dimensional (3-D) data mosaic is a indispensable link in surface measurement and digital terrain map generation. With respect to the mosaic problem of the local unorganized cloud points with rude registration and mass mismatched points, a new mosaic method for 3-D surface based on RANSAC is proposed. Every circular of this method is processed sequentially by random sample with additional shape constraint, data normalization of cloud points, absolute orientation, data denormalization of cloud points, inlier number statistic, etc. After N random sample trials the largest consensus set is selected, and at last the model is re-estimated using all the points in the selected subset. The minimal subset is composed of three non-colinear points which form a triangle. The shape of triangle is considered in random sample selection in order to make the sample selection reasonable. A new coordinate system transformation algorithm presented in this paper is used to avoid the singularity. The whole rotation transformation between the two coordinate systems can be solved by twice rotations expressed by Euler angle vector, each rotation has explicit physical means. Both simulation and real data are used to prove the correctness and validity of this mosaic method. This method has better noise immunity due to its robust estimation property, and has high accuracy as the shape constraint is added to random sample and the data normalization added to the absolute orientation. This method is applicable for high precision measurement of three-dimensional surface and also for the 3-D terrain mosaic.

Using the effects of maternal nutritional indicators (hemoglobin and total protein) on baby's birth weight outcome to forecast a paradigm shift toward increased levels of non-communicable diseases in children.

PubMed

Ahmadu, Baba Usman; Yakubu, Nyandaiti; Yusuph, Haruna; Alfred, Marshall; Bazza, Buba; Lamurde, Abdullahi Suleiman

2013-01-01

Maternal malnutrition can lead to low birth weight in babies, which puts them at risk of developing non-communicable diseases later in life. Evidence from developed countries has shown that low birth weight is associated with a predisposition to higher rates of non-communicable diseases later in life. However, information on this is lacking in developing countries. Thus, this work studied the effects of maternal nutritional indicators (hemoglobin and total protein) on birth weight outcome of babies to forecast a paradigm shift toward increased levels of non-communicable diseases in children. Mother-baby pairs were enrolled in this study using systematic random sampling. Maternal haemogblobin and total proteins were measured using micro-hematocrit and biuret methods, and birth weights of their babies were estimated using the bassinet weighing scale. Of the 168 (100%) babies that participated in this study, 122 (72.6%) were delivered at term and 142 (84.5%) had normal birth weights. Mean comparison of baby's birth weight and maternal hemoglobin was not significant (P = 0.483), that for maternal total protein was also not significant (P = 0.411). Even though positive correlation coefficients were observed between birth weight of babies, maternal hemoglobin and total proteins, these were however not significant. Maternal nutrition did not contribute significantly to low birth weight in our babies. Therefore, association between maternal nutrition and low birth weight to predict future development of non-communicable diseases in our study group is highly unlikely. However, we recommend further work.

Effect of probiotic-fermented, genetically modified soy milk on hypercholesterolemia in hamsters.

PubMed

Tsai, Tsung-Yu; Chen, Li-Ying; Pan, Tzu-Ming

2014-02-01

The rapid progress of biotechnology and molecular biology has led to genetically modified (GM) crops becoming a part of agricultural production. There are concerns that the issues of the functional ingredients in GM products have not been addressed, such as the bioactivities of soy proteins and isoflavones. This study aimed to investigate the effects of probiotic-fermented GM soy milk on hypercholesterolemia, and atherosclerotic risks in hamsters. One hundred and twelve male Golden Syrian hamsters (Mesocricetus auratus) were randomly assigned into 14 groups of 8 animals each. Normal- and high-cholesterol experimental diets were supplemented with GM or non-GM soy milk with or without probiotic-fermentation for 8 weeks. Serum and fecal lipid levels were measured. Moreover, aortic plaque in artery were stained, and thiobarbituric acid reactive substance content, super oxide dismutase activity and caralase activity were determined. GM or non-GM soy milk with or without probiotic-fermentation significantly decreased (p < 0.05) serum TC levels, compared with a high-cholesterol diet group. TC levels in hamsters fed GM soy milk were not significantly different from TC levels in the non-GM soy milk group (p > 0.05). GM soy milk groups can reduce risk of developing atherosclerosis through lowered oxidative stress and reduced atherosclerotic plaque formation in the aorta, and are thus at least equivalent to non-GM soy milk. GM soy milk with or without probiotic-fermentation can improve hypercholesterolemia and reduce the risk of atherosclerosis, and is considered substantially equivalent to non-GM soy milk in terms of these bioactive functions. Copyright © 2012. Published by Elsevier B.V.

Using Changes in Binding Globulins to Assess Oral Contraceptive Compliance

PubMed Central

Westhoff, Carolyn; Petrie, K.A.; Cremers, S.

2012-01-01

Background Validity of oral contraceptive pill (OCP) clinical trial results depends on participant compliance. Ethinyl estradiol (EE2) induces increases in hepatic binding globulin (BG) levels. Measuring these BG increases may provide an effective and convenient approach to distinguishing non-compliant from compliant OCP users in research settings. This analysis evaluated the usefulness of measuring increases in corticosteroid, sex hormone and thyroxine binding globulins (CBG, SHBG, TBG) as measures of OCP compliance. Methods We used frozen serum from a trial that compared ovarian suppression between normal weight and obese women randomized to one of two OCPs containing EE2 and levonorgestrel (LNG). Based on serial LNG measurements during the trial, 17% of participants were non-compliant. We matched non-compliant participants with compliant participants by age, BMI, ethnicity and OCP formulation. We measured CBG, SHBG and TBG levels, and compared change from baseline to 3-month follow-up between the non-compliant and compliant participants. Construction of receiver operator characteristic (ROC) curves allowed comparison of various BG measures. Results Changes in CBG and TBG distinguished OCP non-compliant users from compliant users (area under the ROC curve (AUROC), 0.86 and 0.89, p < 0.01). Changes in SHBG were less discriminating (AUROC 0.69) Conclusions EE2 induced increases in CBG and TBG provide a sensitive integrated marker of compliance with an LNG-containing OCP. PMID:22795088

Shape characteristics of equilibrium and non-equilibrium fractal clusters.

PubMed

Mansfield, Marc L; Douglas, Jack F

2013-07-28

It is often difficult in practice to discriminate between equilibrium and non-equilibrium nanoparticle or colloidal-particle clusters that form through aggregation in gas or solution phases. Scattering studies often permit the determination of an apparent fractal dimension, but both equilibrium and non-equilibrium clusters in three dimensions frequently have fractal dimensions near 2, so that it is often not possible to discriminate on the basis of this geometrical property. A survey of the anisotropy of a wide variety of polymeric structures (linear and ring random and self-avoiding random walks, percolation clusters, lattice animals, diffusion-limited aggregates, and Eden clusters) based on the principal components of both the radius of gyration and electric polarizability tensor indicates, perhaps counter-intuitively, that self-similar equilibrium clusters tend to be intrinsically anisotropic at all sizes, while non-equilibrium processes such as diffusion-limited aggregation or Eden growth tend to be isotropic in the large-mass limit, providing a potential means of discriminating these clusters experimentally if anisotropy could be determined along with the fractal dimension. Equilibrium polymer structures, such as flexible polymer chains, are normally self-similar due to the existence of only a single relevant length scale, and are thus anisotropic at all length scales, while non-equilibrium polymer structures that grow irreversibly in time eventually become isotropic if there is no difference in the average growth rates in different directions. There is apparently no proof of these general trends and little theoretical insight into what controls the universal anisotropy in equilibrium polymer structures of various kinds. This is an obvious topic of theoretical investigation, as well as a matter of practical interest. To address this general problem, we consider two experimentally accessible ratios, one between the hydrodynamic and gyration radii, the other between the viscosity and hydrodynamic radii, as potential measures of shape anisotropy. We also find a strong correlation between anisotropy and effective fractal dimension. These observations should provide new practical methods for quantifying the nature of particle clustering in diverse contexts.

Effects of dietary supplementations with the fibrous root of Rhizoma Coptidis and its main alkaloids on non-specific immunity and disease resistance of common carp.

PubMed

Zhou, Xia; Peng, Yaozong; Li, Ling; He, Kai; Huang, Tao; Mou, Shaoxia; Feng, Min; Han, Bing; Ye, Xiaoli; Li, Xuegang

2016-05-01

The effects of fibrous root of Rhizoma Coptidis (FRC) and its main alkaloids on non-specific immunity and disease resistance of common carp were investigated. The fish were randomly assigned to seven groups: normal control group (NC), groups treated with 12.5 g/kg FRC (FRC-L), 25 g/kg FRC (FRC-M), 50 g/kg FRC (FRC-H), 0.78 g/kg total alkaloids (TA), 0.78 g/kg berberine (BBR), and 0.78 g/kg coptisine (Cop), respectively. Results showed that the activities of myeloperoxidase, lysozyme and respiratory burst were significantly elevated after treated with FRC-M, FRC-H, TA, BBR and Cop, and the complement C3 level and phagocytic activity were significantly increased in FRC-M, TA and BBR treated groups compared with NC group. The real-time PCR analysis indicated that FRC, TA, BBR and Cop could up-regulate the mRNA expression of IL-1β, TNF-α, lysozyme-c and C3, but down-regulate that of IL-10 in the head kidney of common carp. Besides, FRC-M, FRC-H, TA, BBR and Cop significantly enhanced the survival rate of common carp infected with Aeromonas hydrophila, when compared to NC group. It was concluded that the FRC could enhance the non-specific immunity and disease resistance of common carp and the main alkaloids might contribute to these effects. Copyright © 2016 Elsevier B.V. All rights reserved.

Reverberation negatively impacts musical sound quality for cochlear implant users.

PubMed

Roy, Alexis T; Vigeant, Michelle; Munjal, Tina; Carver, Courtney; Jiradejvong, Patpong; Limb, Charles J

2015-09-01

Satisfactory musical sound quality remains a challenge for many cochlear implant (CI) users. In particular, questionnaires completed by CI users suggest that reverberation due to room acoustics can negatively impact their music listening experience. The objective of this study was to more specifically characterize of the effect of reverberation on musical sound quality in CI users, normal hearing (NH) non-musicians, and NH musicians using a previously designed assessment method, called Cochlear Implant-MUltiple Stimulus with Hidden Reference and Anchor (CI-MUSHRA). In this method, listeners were randomly presented with an anechoic musical segment and five-versions of this segment in which increasing amounts of reverberation were artificially added. Participants listened to the six reverberation versions and provided sound quality ratings between 0 (very poor) and 100 (excellent). Results demonstrated that on average CI users and NH non-musicians preferred the sound quality of anechoic versions to more reverberant versions. In comparison, NH musicians could be delineated into those who preferred the sound quality of anechoic pieces and those who preferred pieces with some reverberation. This is the first study, to our knowledge, to objectively compare the effects of reverberation on musical sound quality ratings in CI users. These results suggest that musical sound quality for CI users can be improved by non-reverberant listening conditions and musical stimuli in which reverberation is removed.

Obesogenic television food advertising to children in Malaysia: sociocultural variations

PubMed Central

Ng, See H.; Kelly, Bridget; Se, Chee H.; Chinna, Karuthan; Sameeha, Mohd Jamil; Krishnasamy, Shanthi; MN, Ismail; Karupaiah, Tilakavati

2014-01-01

Background Food advertising on television (TV) is well known to influence children's purchasing requests and models negative food habits in Western countries. Advertising of unhealthy foods is a contributor to the obesogenic environment that is a key driver of rising rates of childhood obesity. Children in developing countries are more at risk of being targeted by such advertising, as there is a huge potential for market growth of unhealthy foods concomitant with poor regulatory infrastructure. Further, in developing countries with multi-ethnic societies, information is scarce on the nature of TV advertising targeting children. Objectives To measure exposure and power of TV food marketing to children on popular multi-ethnic TV stations in Malaysia. Design Ethnic-specific popular TV channels were identified using industry data. TV transmissions were recorded for each channel from November 2012 to August 2013 (16 hr/day) for randomly selected weekdays and weekend days during normal days and repeated during school holidays (n=88 days). Coded food/beverage advertisements were grouped into core (healthy), non-core (non-healthy), or miscellaneous (unclassified) food categories. Peak viewing time (PVT) and persuasive marketing techniques were identified. Results Non-core foods were predominant in TV food advertising, and rates were greater during school holidays compared to normal days (3.51 vs 1.93 food ads/hr/channel, p<0.001). During normal days’ PVT, the ratio of non-core to core food advertising was higher (3.25 food ads/hr/channel), and this more than trebled during school holidays to 10.25 food ads/hr/channel. Popular channels for Indian children had the lowest rate of food advertising relative to other ethnic groups. However, sugary drinks remained a popular non-core product advertised across all broadcast periods and channels. Notably, promotional characters doubled for non-core foods during school holidays compared to normal days (1.91 vs 0.93 food ads/hr/channel, p<0.001). Conclusions This study highlights non-core food advertising, and predominantly sugary drinks are commonly screened on Malaysian TV channels. The majority of these sugary drinks were advertised by multinational companies, and this observation warrants regulatory attention. PMID:25141835

Obesogenic television food advertising to children in Malaysia: sociocultural variations.

PubMed

Ng, See H; Kelly, Bridget; Se, Chee H; Chinna, Karuthan; Sameeha, Mohd Jamil; Krishnasamy, Shanthi; Ismail, M N; Karupaiah, Tilakavati

2014-01-01

Food advertising on television (TV) is well known to influence children's purchasing requests and models negative food habits in Western countries. Advertising of unhealthy foods is a contributor to the obesogenic environment that is a key driver of rising rates of childhood obesity. Children in developing countries are more at risk of being targeted by such advertising, as there is a huge potential for market growth of unhealthy foods concomitant with poor regulatory infrastructure. Further, in developing countries with multi-ethnic societies, information is scarce on the nature of TV advertising targeting children. To measure exposure and power of TV food marketing to children on popular multi-ethnic TV stations in Malaysia. Ethnic-specific popular TV channels were identified using industry data. TV transmissions were recorded for each channel from November 2012 to August 2013 (16 hr/day) for randomly selected weekdays and weekend days during normal days and repeated during school holidays (n=88 days). Coded food/beverage advertisements were grouped into core (healthy), non-core (non-healthy), or miscellaneous (unclassified) food categories. Peak viewing time (PVT) and persuasive marketing techniques were identified. Non-core foods were predominant in TV food advertising, and rates were greater during school holidays compared to normal days (3.51 vs 1.93 food ads/hr/channel, p<0.001). During normal days' PVT, the ratio of non-core to core food advertising was higher (3.25 food ads/hr/channel), and this more than trebled during school holidays to 10.25 food ads/hr/channel. Popular channels for Indian children had the lowest rate of food advertising relative to other ethnic groups. However, sugary drinks remained a popular non-core product advertised across all broadcast periods and channels. Notably, promotional characters doubled for non-core foods during school holidays compared to normal days (1.91 vs 0.93 food ads/hr/channel, p<0.001). This study highlights non-core food advertising, and predominantly sugary drinks are commonly screened on Malaysian TV channels. The majority of these sugary drinks were advertised by multinational companies, and this observation warrants regulatory attention.

Smoking Cessation and Reduction in Schizophrenia (SCARIS) with e-cigarette: study protocol for a randomized control trial

PubMed Central

2014-01-01

Background It is well established in studies across several countries that tobacco smoking is more prevalent among schizophrenic patients than the general population. Electronic cigarettes are becoming increasingly popular with smokers worldwide. To date there are no large randomized trials of electronic cigarettes in schizophrenic smokers. A well-designed trial is needed to compare efficacy and safety of these products in this special population. Methods/Design Intervention: We have designed a randomized controlled trial investigating the efficacy and safety of electronic cigarette. The trial will take the form of a prospective 12-month randomized clinical study to evaluate smoking reduction, smoking abstinence and adverse events in schizophrenic smokers not intending to quit. We will also monitor quality of life, neurocognitive functioning and measure participants’ perception and satisfaction of the product. Outcome measures: A ≥50% reduction in the number of cigarettes/day from baseline, will be calculated at each study visit (“reducers”). Abstinence from smoking will be calculated at each study visit (“quitters”). Smokers who leave the study protocol before its completion and will carry out the Early Termination Visit or who will not satisfy the criteria of “reducers” and “quitters” will be defined “non responders”. Statistical analysis: The differences of continuous variables between the three groups will be evaluated with the Kruskal-Wallis Test, followed by the Dunn multiple comparison test. The differences between the three groups for normally distributed data will be evaluated with ANOVA test one way, followed by the Newman-Keuls multiple comparison test. The normality of the distribution will be evaluated with the Kolmogorov-Smirnov test. Any correlations between the variables under evaluation will be assessed by Spearman r correlation. To compare qualitative data will be used the Chi-square test. Discussion The main strengths of the SCARIS study are the following: it’s the first large RCT on schizophrenic patient, involving in and outpatient, evaluating the effect of a three-arm study design, and a long term of follow-up (52-weeks). The goal is to propose an effective intervention to reduce the risk of tobacco smoking, as a complementary tool to treat tobacco addiction in schizophrenia. Trial registration ClinicalTrials.gov, NCT01979796. PMID:24655473

Effect of Volume of Fluid Resuscitation on Metabolic Normalization in Children Presenting in Diabetic Ketoacidosis: A Randomized Controlled Trial.

PubMed

Bakes, Katherine; Haukoos, Jason S; Deakyne, Sara J; Hopkins, Emily; Easter, Josh; McFann, Kim; Brent, Alison; Rewers, Arleta

2016-04-01

The optimal rate of fluid administration in pediatric diabetic ketoacidosis (DKA) is unknown. Our aim was to determine whether the volume of fluid administration in children with DKA influences the rate of metabolic normalization. We performed a randomized controlled trial conducted in a tertiary pediatric emergency department from December 2007 until June 2010. The primary outcome was time to metabolic normalization; secondary outcomes were time to bicarbonate normalization, pH normalization, overall length of hospital treatment, and adverse outcomes. Children between 0 and 18 years of age were eligible if they had type 1 diabetes mellitus and DKA. Patients were randomized to receive intravenous (IV) fluid at low volume (10 mL/kg bolus + 1.25 × maintenance rate) or high volume (20 mL/kg bolus + 1.5 × maintenance rate) (n = 25 in each). After adjusting for initial differences in bicarbonate levels, time to metabolic normalization was significantly faster in the higher-volume infusion group compared to the low-volume infusion group (hazard ratio [HR] = 2.0; 95% confidence interval [CI] 1.0-3.9; p = 0.04). Higher-volume IV fluid infusion appeared to hasten, to a greater extent, normalization of pH (HR = 2.5; 95% CI 1.2-5.0; p = 0.01) than normalization of serum bicarbonate (HR = 1.2; 95% CI 0.6-2.3; p = 0.6). The length of hospital treatment HR (0.8; 95% CI 0.4-1.5; p = 0.5) and time to discharge HR (0.8; 95% CI 0.4-1.5; p = 0.5) did not differ between treatment groups. Higher-volume fluid infusion in the treatment of pediatric DKA patients significantly shortened metabolic normalization time, but did not change overall length of hospital treatment. ClinicalTrials.gov ID NCT01701557. Copyright © 2016 Elsevier Inc. All rights reserved.

SU-E-T-549: A Combinatorial Optimization Approach to Treatment Planning with Non-Uniform Fractions in Intensity Modulated Proton Therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Papp, D; Unkelbach, J

2014-06-01

Purpose: Non-uniform fractionation, i.e. delivering distinct dose distributions in two subsequent fractions, can potentially improve outcomes by increasing biological dose to the target without increasing dose to healthy tissues. This is possible if both fractions deliver a similar dose to normal tissues (exploit the fractionation effect) but high single fraction doses to subvolumes of the target (hypofractionation). Optimization of such treatment plans can be formulated using biological equivalent dose (BED), but leads to intractable nonconvex optimization problems. We introduce a novel optimization approach to address this challenge. Methods: We first optimize a reference IMPT plan using standard techniques that deliversmore » a homogeneous target dose in both fractions. The method then divides the pencil beams into two sets, which are assigned to either fraction one or fraction two. The total intensity of each pencil beam, and therefore the physical dose, remains unchanged compared to the reference plan. The objectives are to maximize the mean BED in the target and to minimize the mean BED in normal tissues, which is a quadratic function of the pencil beam weights. The optimal reassignment of pencil beams to one of the two fractions is formulated as a binary quadratic optimization problem. A near-optimal solution to this problem can be obtained by convex relaxation and randomized rounding. Results: The method is demonstrated for a large arteriovenous malformation (AVM) case treated in two fractions. The algorithm yields a treatment plan, which delivers a high dose to parts of the AVM in one of the fractions, but similar doses in both fractions to the normal brain tissue adjacent to the AVM. Using the approach, the mean BED in the target was increased by approximately 10% compared to what would have been possible with a uniform reference plan for the same normal tissue mean BED.« less

Body mass index had different effects on premenopausal and postmenopausal breast cancer risks: a dose-response meta-analysis with 3,318,796 subjects from 31 cohort studies.

PubMed

Chen, Yanzi; Liu, Li; Zhou, Quan; Imam, Mustapha Umar; Cai, Jialin; Wang, Yaxuan; Qi, Minjie; Sun, Panpan; Ping, Zhiguang; Fu, Xiaoli

2017-12-08

There is sufficient evidence supporting a relationship between increased body mass index (BMI) and an increased risk for breast cancer among postmenopausal women. However, most studies have found a decreased risk for premenopausal breast cancer. This study was conducted to find out the different effects of BMI on the risk of breast cancer among premenopausal and postmenopausal women, and explore the potential factors that influence the associations. A dose-response meta-analysis with 3,318,796 participants from 31 articles was conducted. Cohort studies that included BMI and corresponding breast cancer risk were selected through various databases including PubMed, Medline, Web of Science, the China National Knowledge Infrastructure (CNKI) and Chinese Scientific Journals (VIP). Random effects models were used for analyzing the data. The summary relative risks (RRs) were 1.33 (95%CI: 1.20-1.48) and 0.94(95%CI: 0.80-1.11) among postmenopausal and premenopausal women, respectively. The dose-response meta-analysis indicated a positive non-linear association between BMI and breast cancer risk among postmenopausal women, and compared to the mean level of the normal BMI category (21.5 kg/m 2 ) the RR in total postmenopausal women were1.03 (95% CI: 1.02-1.05) per 1 kg/m 2 increment. However, no statistically significant association among total premenopausal women was detected. In subgroup analysis among European premenopausal women, the summary RR was 0.79(95%CI: 0.70-0.88). The non-linear relationship showed a negative non-linear association between BMI and breast cancer risk among European premenopausal women. When compared to the mean level of the normal BMI category, the RRs were 0.98 (95%CI: 0.96-1.00) per 1 kg/m 2 increment, respectively. In line with previous studies BMI had different effects on pre-menopausal and postmenopausal breast cancer risk. However, contrary to previous studies, a high BMI was not associated with decreased risk in total pre-menopausal women. More research is needed to better understand these differences.

The impact of sample non-normality on ANOVA and alternative methods.

PubMed

Lantz, Björn

2013-05-01

In this journal, Zimmerman (2004, 2011) has discussed preliminary tests that researchers often use to choose an appropriate method for comparing locations when the assumption of normality is doubtful. The conceptual problem with this approach is that such a two-stage process makes both the power and the significance of the entire procedure uncertain, as type I and type II errors are possible at both stages. A type I error at the first stage, for example, will obviously increase the probability of a type II error at the second stage. Based on the idea of Schmider et al. (2010), which proposes that simulated sets of sample data be ranked with respect to their degree of normality, this paper investigates the relationship between population non-normality and sample non-normality with respect to the performance of the ANOVA, Brown-Forsythe test, Welch test, and Kruskal-Wallis test when used with different distributions, sample sizes, and effect sizes. The overall conclusion is that the Kruskal-Wallis test is considerably less sensitive to the degree of sample normality when populations are distinctly non-normal and should therefore be the primary tool used to compare locations when it is known that populations are not at least approximately normal. © 2012 The British Psychological Society.

The effect of language experience on perceptual normalization of Mandarin tones and non-speech pitch contours.

PubMed

Luo, Xin; Ashmore, Krista B

2014-06-01

Context-dependent pitch perception helps listeners recognize tones produced by speakers with different fundamental frequencies (f0s). The role of language experience in tone normalization remains unclear. In this cross-language study of tone normalization, native Mandarin and English listeners were asked to recognize Mandarin Tone 1 (high-flat) and Tone 2 (mid-rising) with a preceding Mandarin sentence. To further test whether context-dependent pitch perception is speech-specific or domain-general, both language groups were asked to identify non-speech flat and rising pitch contours with a preceding non-speech flat pitch contour. Results showed that both Mandarin and English listeners made more rising responses with non-speech than with speech stimuli, due to differences in spectral complexity and listening task between the two stimulus types. English listeners made more rising responses than Mandarin listeners with both speech and non-speech stimuli. Contrastive context effects (more rising responses in the high-f0 context than in the low-f0 context) were found with both speech and non-speech stimuli for Mandarin listeners, but not for English listeners. English listeners' lack of tone experience may have caused more rising responses and limited use of context f0 cues. These results suggest that context-dependent pitch perception in tone normalization is domain-general, but influenced by long-term language experience.

Diffusion Processes Satisfying a Conservation Law Constraint

DOE PAGES

Bakosi, J.; Ristorcelli, J. R.

2014-03-04

We investigate coupled stochastic differential equations governing N non-negative continuous random variables that satisfy a conservation principle. In various fields a conservation law requires that a set of fluctuating variables be non-negative and (if appropriately normalized) sum to one. As a result, any stochastic differential equation model to be realizable must not produce events outside of the allowed sample space. We develop a set of constraints on the drift and diffusion terms of such stochastic models to ensure that both the non-negativity and the unit-sum conservation law constraint are satisfied as the variables evolve in time. We investigate the consequencesmore » of the developed constraints on the Fokker-Planck equation, the associated system of stochastic differential equations, and the evolution equations of the first four moments of the probability density function. We show that random variables, satisfying a conservation law constraint, represented by stochastic diffusion processes, must have diffusion terms that are coupled and nonlinear. The set of constraints developed enables the development of statistical representations of fluctuating variables satisfying a conservation law. We exemplify the results with the bivariate beta process and the multivariate Wright-Fisher, Dirichlet, and Lochner’s generalized Dirichlet processes.« less

Diffusion Processes Satisfying a Conservation Law Constraint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bakosi, J.; Ristorcelli, J. R.

We investigate coupled stochastic differential equations governing N non-negative continuous random variables that satisfy a conservation principle. In various fields a conservation law requires that a set of fluctuating variables be non-negative and (if appropriately normalized) sum to one. As a result, any stochastic differential equation model to be realizable must not produce events outside of the allowed sample space. We develop a set of constraints on the drift and diffusion terms of such stochastic models to ensure that both the non-negativity and the unit-sum conservation law constraint are satisfied as the variables evolve in time. We investigate the consequencesmore » of the developed constraints on the Fokker-Planck equation, the associated system of stochastic differential equations, and the evolution equations of the first four moments of the probability density function. We show that random variables, satisfying a conservation law constraint, represented by stochastic diffusion processes, must have diffusion terms that are coupled and nonlinear. The set of constraints developed enables the development of statistical representations of fluctuating variables satisfying a conservation law. We exemplify the results with the bivariate beta process and the multivariate Wright-Fisher, Dirichlet, and Lochner’s generalized Dirichlet processes.« less

Hydrogen sulfide releasing naproxen offers better anti-inflammatory and chondroprotective effect relative to naproxen in a rat model of zymosan induced arthritis.

PubMed

Dief, A E; Mostafa, D K; Sharara, G M; Zeitoun, T H

2015-04-01

Hydrogen sulfide (H2S) is rapidly gaining ground as a physiological mediator of inflammation, but there is no clear consensus as to its precise role in inflammation. Therefore, this study was undertaken to evaluate the effects of ATB-346 as a novel H2S-releasing naproxen compared to naproxen, as a traditional non-steroidal anti-inflammatory drug on zymosan induced mono-arthritis in rats. Male Wistar rats (n=48) were randomly assigned to four main groups: normal control, untreated arthritis, Naproxen and ATB-346 treated groups. Mono-arthritis was induced by intra-articular injection of zymosan into the knee joints. Mechanical hypernociception and joint swelling were evaluated at 6 hours and 5 days. Inflammatory cellular recruitment and adherence, tumor necrosis factor alpha, nuclear factor kappa β, total sulfide levels, and histological changes were evaluated in knee lavages, blood or joint tissues at selected time points. Zymosan injection evoked knee inflammation and pain as characterized by mechanical hypernociception, impaired gait, joint swelling with inflammatory exudation and histological changes. Treatment with ATB-346 attenuated nociceptive responses, inflammatory cellular and biochemical changes in comparison to naproxen. Only ATB-346 was able to suppress neutrophil adherence and to preserve normal articular structure. H2S releasing naproxen represents an advancement over the parent drug, naproxen. Apart from the superior anti-inflammatory and anti-noceiceptive activity, ATB-346 offered a distinguished chondroprotective effect and is almost devoid from naproxen deleterious effects on articular cartilage.

Hierarchy of evidence: differences in results between non-randomized studies and randomized trials in patients with femoral neck fractures.

PubMed

Bhandari, Mohit; Tornetta, Paul; Ellis, Thomas; Audige, Laurent; Sprague, Sheila; Kuo, Jonathann C; Swiontkowski, Marc F

2004-01-01

There have been a number of non-randomized studies comparing arthroplasty with internal fixation in patients with femoral neck fractures. However, there remains considerable debate about whether the results of non-randomized studies are consistent with the results of randomized, controlled trials. Given the economic burden of hip fractures, it remains essential to identify therapies to improve outcomes; however, whether data from non-randomized studies of an intervention should be used to guide patient care remains unclear. We aimed to determine whether the pooled results of mortality and revision surgery among non-randomized studies were similar to those of randomized trials in studies comparing arthroplasty with internal fixation in patients with femoral neck fractures. We conducted a Medline search from 1969 to June 2002, identifying both randomized and non-randomized studies comparing internal fixation with arthroplasty in patients with femoral neck fractures. Additional strategies to identify relevant articles included Cochrane database, SCISEARCH, textbooks, annual meeting programs, and content experts. We abstracted information on mortality and revision rates in each study and compared the pooled results between non-randomized and randomized studies. In addition, we explored potential reasons for dissimilar results between the two study designs. We identified 140 citations that addressed the general topic of comparison of arthroplasty and internal fixation for hip fracture. Of these, 27 studies met the eligibility criteria, 13 of which were non-randomized studies and 14 of which were randomized trials. Mortality data was available in all 13 non-randomized studies ( n=3108 patients) and in 12 randomized studies ( n=1767 patients). Non-randomized studies overestimated the risk of mortality by 40% when compared with the results of randomized trials (relative risk 1.44 vs 1.04, respectively). Information on revision risk was available in 9 non-randomized studies ( n=2764 patients) and all 14 randomized studies ( n=1901 patients). Both estimates from non-randomized and randomized studies revealed a significant reduction in the risk of revision surgery with arthroplasty compared with internal fixation (relative risk 0.38 vs 0.23, respectively). The reduction in the risk of revision surgery with arthroplasty compared with internal fixation was 62% for non-randomized studies and 77% for randomized trials. Thus, non-randomized studies underestimated the relative benefit of arthroplasty by 19.5%. Non-randomized studies with point estimates of relative risk similar to the pooled estimate for randomized trials all controlled for patient age, gender, and fracture displacement in their comparisons of mortality. We were unable to identify reasons for differences in the revision rate results between the study designs. Similar to other reports in medical subspecialties, non-randomized studies provided results dissimilar to randomized trials of arthroplasty vs internal fixation for mortality and revision rates in patients with femoral neck fractures. Investigators should be aware of these discrepancies when evaluating the merits of alternative surgical interventions, especially when both randomized trials and non-randomized comparative studies are available.

Accommodation and pupil responses to random-dot stereograms

PubMed Central

Suryakumar, Rajaraman; Allison, Robert

2015-01-01

We investigated the dynamics of accommodative and pupillary responses to random-dot stereograms presented in crossed and uncrossed disparity in six visually normal young adult subjects (mean age = 25.8 ± 3.1 years). Accommodation and pupil measures were monitored monocularly with a custom built photorefraction system while subjects fixated at the center of a random-dot stereogram. On each trial, the stereogram initially depicted a flat plane and then changed to depict a sinusoidal corrugation in depth while fixation remained constant. Increase in disparity specified depth resulted in pupil constriction during both crossed and uncrossed disparity presentations. The change in pupil size between crossed and uncrossed disparity conditions was not significantly different (p > 0.05). The change in pupil size was also accompanied by a small concomitant increase in accommodation. In addition, the dynamic properties of pupil responses varied as a function of their initial (starting) diameter. The finding that accommodation and pupil responses increased with disparity regardless of the sign of retinal disparity suggests that these responses were driven by apparent depth rather than shifts in mean simulated distance of the stimulus. Presumably the need for the increased depth of focus when viewing stimuli extended in depth results in pupil constriction which also results in a concomitant change in accommodation. Starting position effects in pupil response confirm the non-linearity in the operating range of the pupil. PMID:25891121

Melody and pitch processing in five musical savants with congenital blindness.

PubMed

Pring, Linda; Woolf, Katherine; Tadic, Valerie

2008-01-01

We examined absolute-pitch (AP) and short-term musical memory abilities of five musical savants with congenital blindness, seven musicians, and seven non-musicians with good vision and normal intelligence in two experiments. In the first, short-term memory for musical phrases was tested and the savants and musicians performed statistically indistinguishably, both significantly outperforming the non-musicians and remembering more material from the C major scale sequences than random trials. In the second experiment, participants learnt associations between four pitches and four objects using a non-verbal paradigm. This experiment approximates to testing AP ability. Low statistical power meant the savants were not statistically better than the musicians, although only the savants scored statistically higher than the non-musicians. The results are evidence for a musical module, separate from general intelligence; they also support the anecdotal reporting of AP in musical savants, which is thought to be necessary for the development of musical-savant skill.

A comparison of three random effects approaches to analyze repeated bounded outcome scores with an application in a stroke revalidation study.

PubMed

Molas, Marek; Lesaffre, Emmanuel

2008-12-30

Discrete bounded outcome scores (BOS), i.e. discrete measurements that are restricted on a finite interval, often occur in practice. Examples are compliance measures, quality of life measures, etc. In this paper we examine three related random effects approaches to analyze longitudinal studies with a BOS as response: (1) a linear mixed effects (LM) model applied to a logistic transformed modified BOS; (2) a model assuming that the discrete BOS is a coarsened version of a latent random variable, which after a logistic-normal transformation, satisfies an LM model; and (3) a random effects probit model. We consider also the extension whereby the variability of the BOS is allowed to depend on covariates. The methods are contrasted using a simulation study and on a longitudinal project, which documents stroke rehabilitation in four European countries using measures of motor and functional recovery. Copyright 2008 John Wiley & Sons, Ltd.

Therapeutic effect of adeno-associated virus (AAV)-mediated ADNF-9 expression on cochlea of kanamycin-deafened guinea pigs.

PubMed

Zheng, Guoxi; Zhu, Zhu; Zhu, Kang; Wei, Junrong; Jing, Yang; Duan, Maoli

2013-10-01

rAAV-NT4-ADNF-9 could ameliorate the damage to auditory function and repair previous impairment of cochlear hair cell loss induced by kanamycin. To investigate the therapeutic effect of ADNF-9 on cochlear hair cells using the recombinant adeno-associated virus (AAV) carrying fusion gene NT4-ADNF-9 and the kanamycin-deafened guinea pig model. Forty white guinea pigs with normal auricle reflex and normal auditory brainstem responses (ABRs) were randomly divided into four groups. Kanamycin was administered to the animals in groups A, B, and C to establish the deafened guinea pig model. rAAV-NT4-ADNF-9, vector only, and artificial perilymph were then delivered to the cochlear tissue of animals in groups A, B, and C, respectively, through the round window membrane. Animals in group D did not receive any treatment and acted as normal controls. The hearing thresholds on the surgery side were recorded before and after the transfection treatment. Fourteen days after treatment, cochleae were removed for paraffin slide preparation and cochlear surface preparation. A phase contrast microscope was used to observe the protective effect of ADNF-9 on hair cells. Significant reduction of the ABR threshold was observed after rAAV-NT4-ADNF-9 treatment (p < 0.05). After 14 days of treatment, the ABR threshold was also significantly different between the rAAV-NT4-ADNF-9-infected group and the non-infected group. Moreover, phase contrast microscopy showed significantly less hair cell damage or hair cell loss in the group treated with rAAV-NT4-ADNF-9 than in the groups treated with vector only or artificial perilymph (p < 0.05).

Effect of rocuronium on the bispectral index under anesthesia and tracheal intubation.

PubMed

Yue, Hui; Han, Jinyu; Liu, Ling; Wang, Kaiyuan; Li, Jincheng

2016-12-01

The aim of the present study was to investigate the effect of various doses of rocuronium on bispectral index (BIS) responses to propofol induction and tracheal intubation, as well as the role of the non-depolarization muscle relaxant rocuronium on the depth of sedation. A total of 72 patients (American Society of Anesthesiologists physical status I-II) were anaesthetized with propofol using a target-controlled infusion, and randomly divided into two sedation level groups (n=36). The patients were divided into 2 groups according to the BIS value: A normal sedation group (group 1), with a stable BIS value at 40-60, and a deep sedation group (group 2), with a BIS value <20 or with burst suppression. Each group was randomly divided into 4 subgroups A-D (n=9) according to the various doses of rocuronium (0.3, 0.6, 0.9 and 1.2 mg/kg). Tracheal intubation was performed after 2 min of rocuronium administration. BIS, electromyography (EMG), heart rate (HR) and mean arterial pressure (MAP) were recorded continuously and averaged over 1 min during baseline (T1), steady state (T2), 2 min after rocuronium infusion (T3), and 0, 2 and 5 min after tracheal intubation. The results demonstrated that HR and MAP decreased significantly at T2 and T3 compared with T1. Following tracheal intubation (L0), HR and MAP significantly increased compared with T2 and T3, and returned to levels similar to those prior to intubation after 5 min. In group 1C and 1D, BIS was significantly decreased at T3 compared with T2; BIS was significantly increased at L0 compared with T3 in group 1A and 1B. EMG at earlier stages of anesthesia was significantly higher compared with other points, and was significantly increased at L0 compared with T3 in group 1A and 1B. These results demonstrated that BIS response may be associated with the dosage of rocuronium in the normal sedation group, although no association was observed with the deep sedation group. Tracheal intubation resulted in marked hemodynamic changes under both normal and deep sedation.

Population pharmacokinetic modeling of sepantronium bromide (YM155), a small molecule survivin suppressant, in patients with non-small cell lung cancer, hormone refractory prostate cancer, or unresectable stage III or IV melanoma.

PubMed

Aoyama, Yumiko; Kaibara, Atsunori; Takada, Akitsugu; Nishimura, Tetsuya; Katashima, Masataka; Sawamoto, Taiji

2013-04-01

Purpose Population pharmacokinetics (PK) of sepantronium bromide (YM155) was characterized in patients with non-small cell lung cancer, hormone refractory prostate cancer, or unresectable stage III or IV melanoma and enrolled in one of three phase 2 studies conducted in Europe or the U.S. Method Sepantronium was administered as a continuous intravenous infusion (CIVI) at 4.8 mg/m(2)/day over 7 days every 21 days. Population PK analysis was performed using a linear one-compartment model involving total body clearance (CL) and volume of distribution with an inter-individual random effect on CL and a proportional residual errors to describe 578 plasma sepantronium concentrations obtained from a total of 96 patients by NONMEM Version VI. The first-order conditional estimation method with interaction was applied. Results The one-compartment model with one random effect on CL and two different proportional error models provided an adequate description of the data. Creatinine clearance (CLCR), cancer type, and alanine aminotransferase (ALT) were recognized as significant covariates of CL. CLCR was the most influential covariate on sepantronium exposure and predicted to contribute to a 25 % decrease in CL for patients with moderately impaired renal function (CLCR = 40 mL/min) compared to patients with normal CLCR. Cancer type and ALT had a smaller but nonetheless significant contribution. Other patient characteristics such as age, gender, and race were not considered as significant covariates of CL. Conclusions The results provide the important information for optimizing the therapeutic efficacy and minimizing the toxicity for sepantronium in cancer therapy.

Multi-step resistive switching behavior of Li-doped ZnO resistance random access memory device controlled by compliance current

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lin, Chun-Cheng; Department of Mathematic and Physical Sciences, R.O.C. Air Force Academy, Kaohsiung 820, Taiwan; Tang, Jian-Fu

2016-06-28

The multi-step resistive switching (RS) behavior of a unipolar Pt/Li{sub 0.06}Zn{sub 0.94}O/Pt resistive random access memory (RRAM) device is investigated. It is found that the RRAM device exhibits normal, 2-, 3-, and 4-step RESET behaviors under different compliance currents. The transport mechanism within the device is investigated by means of current-voltage curves, in-situ transmission electron microscopy, and electrochemical impedance spectroscopy. It is shown that the ion transport mechanism is dominated by Ohmic behavior under low electric fields and the Poole-Frenkel emission effect (normal RS behavior) or Li{sup +} ion diffusion (2-, 3-, and 4-step RESET behaviors) under high electric fields.

A randomized controlled non-inferiority study comparing the antiemetic effect between intravenous granisetron and oral azasetron based on estimated 5-HT3 receptor occupancy.

PubMed

Endo, Junki; Iihara, Hirotoshi; Yamada, Maya; Yanase, Koumei; Kamiya, Fumihiko; Ito, Fumitaka; Funaguchi, Norihiko; Ohno, Yasushi; Minatoguchi, Shinya; Itoh, Yoshinori

2012-09-01

The acute antiemetic effect was compared between oral azasetron and intravenous granisetron based on the 5-hydroxytryptamine(3) (5-HT(3)) receptor occupancy theory. Receptor occupancy was estimated from reported data on plasma concentrations and affinity constants to 5-HT(3) receptor. A randomized non-inferiority study comparing acute antiemetic effects between oral azasetron and intravenous granisetron was performed in 105 patients receiving the first course of carboplatin-based chemotherapy for lung cancer. Azasetron exhibited the highest 5-HT(3) receptor occupancy among various first-generation 5-HT(3) antagonists. The complete response to oral azasetron was shown to be non-inferior to that of intravenous granisetron, in which the risk difference was 0.0004 (95% confidence interval: -0.0519-0.0527). The lower limit of the confidence intervals did not exceed the negative non-inferiority margin (-0.1). The complete response during the overall period was not different (68% versus 67%). Oral azasetron was found to be non-inferior to intravenous granisetron in the acute antiemetic effect against moderately emetogenic chemotherapy.

Log-normal distribution from a process that is not multiplicative but is additive.

PubMed

Mouri, Hideaki

2013-10-01

The central limit theorem ensures that a sum of random variables tends to a Gaussian distribution as their total number tends to infinity. However, for a class of positive random variables, we find that the sum tends faster to a log-normal distribution. Although the sum tends eventually to a Gaussian distribution, the distribution of the sum is always close to a log-normal distribution rather than to any Gaussian distribution if the summands are numerous enough. This is in contrast to the current consensus that any log-normal distribution is due to a product of random variables, i.e., a multiplicative process, or equivalently to nonlinearity of the system. In fact, the log-normal distribution is also observable for a sum, i.e., an additive process that is typical of linear systems. We show conditions for such a sum, an analytical example, and an application to random scalar fields such as those of turbulence.

Maintenance treatment of Uracil and Tegafur (UFT) in responders following first-line fluorouracil-based chemotherapy in metastatic gastric cancer: a randomized phase II study.

PubMed

Li, Wenhua; Zhao, Xiaoying; Wang, Huijie; Liu, Xin; Zhao, Xinmin; Huang, Mingzhu; Qiu, Lixin; Zhang, Wen; Chen, Zhiyu; Guo, Weijian; Li, Jin; Zhu, Xiaodong

2017-06-06

Maintenance therapy proves to be effective in advanced lung and breast cancer after initial chemotherapy. The purpose of this phase II study was to evaluate the efficacy and safety of Uracil and Tegafur (UFT) maintenance in metastatic gastric cancer patients following the first-line fluorouracil-based chemotherapy. Metastatic gastric cancer patients with stable disease or a better response after the completion of first-line chemotherapy were randomized to oral UFT (360mg/m2 × 2 weeks) every 3 weeks until disease progression/intolerable toxicity or to observation (OBS). The primary endpoint was progression-free survival (PFS); the secondary endpoints were overall survival (OS) and safety. The trial was closed after the interim analysis of the 58 enrolled (120 planned) patients. Median PFS was not improved in the UFT group compared with the OBS group (3.2 months versus 3.6 months, P = 0.752), as well as the median OS (14.2 months for both, P = 0.983). However, subgroup analysis showed that low baseline hemoglobin (< 120 g/L) was associated with poorer PFS with maintenance therapy (P = 0.032), while the normal hemoglobin patients benefit from the UFT treatment (P = 0.008). Grade 3 to 4 toxicities in the UFT group were anemia (3.4%), thrombocytopenia (3.4%) and diarrhea (6.9%). This trial did not show superiority of UFT maintenance in non-selected patients responding to fluorouracil-based first-line chemotherapy. The normal hemoglobin level at baseline is a predictive biomarker for favorable patient subsets from the maintenance treatment.

Laplacian normalization and random walk on heterogeneous networks for disease-gene prioritization.

PubMed

Zhao, Zhi-Qin; Han, Guo-Sheng; Yu, Zu-Guo; Li, Jinyan

2015-08-01

Random walk on heterogeneous networks is a recently emerging approach to effective disease gene prioritization. Laplacian normalization is a technique capable of normalizing the weight of edges in a network. We use this technique to normalize the gene matrix and the phenotype matrix before the construction of the heterogeneous network, and also use this idea to define the transition matrices of the heterogeneous network. Our method has remarkably better performance than the existing methods for recovering known gene-phenotype relationships. The Shannon information entropy of the distribution of the transition probabilities in our networks is found to be smaller than the networks constructed by the existing methods, implying that a higher number of top-ranked genes can be verified as disease genes. In fact, the most probable gene-phenotype relationships ranked within top 3 or top 5 in our gene lists can be confirmed by the OMIM database for many cases. Our algorithms have shown remarkably superior performance over the state-of-the-art algorithms for recovering gene-phenotype relationships. All Matlab codes can be available upon email request. Copyright © 2015 Elsevier Ltd. All rights reserved.

Improving the dictionary lookup approach for disease normalization using enhanced dictionary and query expansion

PubMed Central

Jonnagaddala, Jitendra; Jue, Toni Rose; Chang, Nai-Wen; Dai, Hong-Jie

2016-01-01

The rapidly increasing biomedical literature calls for the need of an automatic approach in the recognition and normalization of disease mentions in order to increase the precision and effectivity of disease based information retrieval. A variety of methods have been proposed to deal with the problem of disease named entity recognition and normalization. Among all the proposed methods, conditional random fields (CRFs) and dictionary lookup method are widely used for named entity recognition and normalization respectively. We herein developed a CRF-based model to allow automated recognition of disease mentions, and studied the effect of various techniques in improving the normalization results based on the dictionary lookup approach. The dataset from the BioCreative V CDR track was used to report the performance of the developed normalization methods and compare with other existing dictionary lookup based normalization methods. The best configuration achieved an F-measure of 0.77 for the disease normalization, which outperformed the best dictionary lookup based baseline method studied in this work by an F-measure of 0.13. Database URL: https://github.com/TCRNBioinformatics/DiseaseExtract PMID:27504009

Short Term Culture of Vitrified Human Ovarian Cortical Tissue to Assess the Cryopreservation Outcome: Molecular and Morphological Analysis.

PubMed

Ramezani, Mehdi; Salehnia, Mojdeh; Jafarabadi, Mina

2017-01-01

The aim of the present study was to evaluate the effectiveness of human ovarian vitrification protocol followed with in vitro culture at the morphological and molecular levels. Ovarian tissues were obtained from 10 normal transsexual women and cut into small pieces and were divided into non-vitrified and vitrified groups and some of the tissues fragments in both groups were randomly cultured for two weeks. The morphological study using hematoxylin and eosin and Masson's trichrome staining was done. The analysis of mean follicular density, 17-β estradiol (E2) and anti mullerian hormone (AMH), and real-time RT-PCR was down for the evaluation of expression of genes related to folliculogenesis. Data were compared by paired-samples and independent-samples T test. Values of p<0.05 were considered statistically significant. The proportion of normal follicles did not show significant difference between vitrified and non-vitrified groups before and after culture but these rates and the mean follicle density significantly decreased in both cultured tissues (p<0.05). The expression of genes was similar in vitrified and non-vitrified groups but in cultured tissues the expression of GDF9 and FSHR genes increased and the expression of FIGLA and KIT-L genes decreased (p<0.05). An increase in E2 and AMH concentration was observed after 14 days of culture in both groups. In conclusion, the present study indicated that the follicular development and gene expression in vitrified ovarian tissue was not altered before and after in vitro culture, thus this method could be useful for fertility preservation; however, additional studies are needed to improve the culture condition.

Transcriptome instability as a molecular pan-cancer characteristic of carcinomas.

PubMed

Sveen, Anita; Johannessen, Bjarne; Teixeira, Manuel R; Lothe, Ragnhild A; Skotheim, Rolf I

2014-08-10

We have previously proposed transcriptome instability as a genome-wide, pre-mRNA splicing-related characteristic of colorectal cancer. Here, we explore the hypothesis of transcriptome instability being a general characteristic of cancer. Exon-level microarray expression data from ten cancer datasets were analyzed, including breast cancer, cervical cancer, colorectal cancer, gastric cancer, lung cancer, neuroblastoma, and prostate cancer (555 samples), as well as paired normal tissue samples from the colon, lung, prostate, and stomach (93 samples). Based on alternative splicing scores across the genomes, we calculated sample-wise relative amounts of aberrant exon skipping and inclusion. Strong and non-random (P < 0.001) correlations between these estimates and the expression levels of splicing factor genes (n = 280) were found in most cancer types analyzed (breast-, cervical-, colorectal-, lung- and prostate cancer). This suggests a biological explanation for the splicing variation. Surprisingly, these associations prevailed in pan-cancer analyses. This is in contrast to the tissue and cancer specific patterns observed in comparisons across healthy tissue samples from the colon, lung, prostate, and stomach, and between paired cancer-normal samples from the same four tissue types. Based on exon-level expression profiling and computational analyses of alternative splicing, we propose transcriptome instability as a molecular pan-cancer characteristic. The affected cancers show strong and non-random associations between low expression levels of splicing factor genes, and high amounts of aberrant exon skipping and inclusion, and vice versa, on a genome-wide scale.

Cold pressor stimulus temperature and resting masseter muscle haemodynamics in normal humans.

PubMed

Maekawa, K; Kuboki, T; Clark, G T; Shinoda, M; Yamashita, A

1998-11-01

Cold pressor stimulation reportedly increases sympathetic nerve activity in human skeletal muscles. This study examined the effect of cold pressor stimulation on the resting haemodynamics of the right masseter muscle in normal individuals, using near-infrared spectroscopy. Nine healthy non-smoking males with no history of chronic muscle pain or vascular headaches participated. Their right hand was immersed in a water bath (4, 10, 15 degrees C) for exactly 1 min. Each trial lasted 7 min (1 min before, 1 min during, 5 min after stimulation) and a strictly random order was utilized for the three test temperatures and the mock trial. Masseter muscle haemoglobin concentration and oxygen saturation, as well as heart rate and blood pressure, were continuously recorded in each trial. After completing the four trials, each participant produced and sustained a 30-s maximum voluntary clench in the intercuspal position. Data across the four trials were baseline-corrected and then magnitude-normalized to the individual's highest absolute haemoglobin and oxygen signal during the 30-s maximal clenching effort. Haemoglobin and oxygen saturation increased progressively during cold pressor stimulation as the water temperature decreased (Hb, p < 0.0001; O2, p = 0.0327); very little effect was seen during the mock trial. Heart rate and blood pressure also increased progressively during the stimulation as the temperature decreased (heart rate, p = 0.0013; systolic blood pressure, p = 0.0042; diastolic blood pressure, p = 0.0156). These data suggest that cold pressor, stimulation induces a strong increase in intramuscular blood volume which appears to be due to both a local vasodilative response and increased cardiac output.

The Effects of Supplemental Zinc and Honey on Wound Healing in Rats

PubMed Central

Sazegar, Ghasem; Seyed Reza, Attarzadeh Hosseini; Behravan, Effat

2011-01-01

Objective(s) Clinicians have long been searching for ways to obtain "super normal" wound healing. Zinc supplementation improves the healing of open wounds. Honey can improve the wound healing with its antibacterial properties. Giving supplemental zinc to normal rats can increase the wound tensile strength. This work is to study the concurrent effects of zinc and honey in wound healing of normal rats. Materials and Methods One hundred and seventy two young rats were randomly divided into four groups: control, zinc-supplement, applied honey, zinc-supplement and applied honey. Two areas of skin about 4 cm² were excised. The wound area was measured every 2 days. After 3 weeks, all animals were killed and tensile strength of wounds, zinc concentration of blood and histological improvement of wounds were evaluated. The results were analyzed using two-way ANOVA and the mean differences were tested. Results It was found that honey could inhibit the bacterial growth in skin excisions. The tensile strength was increased significantly in the second to fourth groups at 21st day (P< 0.001). Also there was a significant increase in tensile strength at the same time in the fourth group. The results of the histological study showed a considerable increase in the collagen fibers, re-epithelialization and re-vascularization in the second to fourth groups. Conclusion The results of the present study indicate that zinc sulfate could retard re-epithelialization, but when used with natural honey (administered topically) it could have influent wound healing in non-zinc-deficient subjects as well. PMID:23493488

Effects of Shuttlecock-Playing on Physical Fitness in College Students

ERIC Educational Resources Information Center

Zhang, Tingran; Luo, Jiong

2015-01-01

The purpose of this study was to investigate the exercise intensity and the physical fitness effect of shuttlecock playing. 18 normal body weight college students voluntarily participated in this study. They were randomly assigned to shuttlecock playing (SCP) and control groups. The SCP underwent a 15-week shuttlecock-playing program, but the…

The Effect of General Statistical Fiber Misalignment on Predicted Damage Initiation in Composites

NASA Technical Reports Server (NTRS)

Bednarcyk, Brett A.; Aboudi, Jacob; Arnold, Steven M.

2014-01-01

A micromechanical method is employed for the prediction of unidirectional composites in which the fiber orientation can possess various statistical misalignment distributions. The method relies on the probability-weighted averaging of the appropriate concentration tensor, which is established by the micromechanical procedure. This approach provides access to the local field quantities throughout the constituents, from which initiation of damage in the composite can be predicted. In contrast, a typical macromechanical procedure can determine the effective composite elastic properties in the presence of statistical fiber misalignment, but cannot provide the local fields. Fully random fiber distribution is presented as a special case using the proposed micromechanical method. Results are given that illustrate the effects of various amounts of fiber misalignment in terms of the standard deviations of in-plane and out-of-plane misalignment angles, where normal distributions have been employed. Damage initiation envelopes, local fields, effective moduli, and strengths are predicted for polymer and ceramic matrix composites with given normal distributions of misalignment angles, as well as fully random fiber orientation.

Consequences of non-random species loss for decomposition dynamics: Experimental evidence for additive and non-additive effects

Treesearch

Becky A. Ball; Mark D. Hunter; John S. Kominoski; Christopher M. Swan; Mark A. Bradford

2008-01-01

Although litter decomposition is a fundamental ecological process, most of our understanding comes from studies of single-species decay. Recently, litter-mixing studies have tested whether monoculture data can be applied to mixed-litter systems. These studies have mainly attempted to detect non-additive effects of litter mixing, which address potential consequences of...

Prevention of metabolic disorders with telmisartan and indapamide in a Chinese population with high-normal blood pressure.

PubMed

Peng, Jie; Zhao, Yingxin; Zhang, Hua; Liu, Zhendong; Wang, Zhihao; Tang, Mengxiong; Zhong, Ming; Lu, Fanghong; Zhang, Wei

2015-02-01

High-normal blood pressure is considered a precursor of stage 1 hypertension that is associated with metabolic disorders. This study aims to investigate whether the pharmacologic treatment of high-normal blood pressure affects metabolism, especially in abdominally obese individuals, and the pharmacoeconomics of two antihypertensive agents, telmisartan and indapamide. Subjects with high-normal blood pressure were randomly assigned to receive telmisartan, indapamide or placebo for 3 years. All the subjects were instructed to modify their lifestyle to reduce blood pressure throughout the study. A total of 221 subjects were randomly assigned to telmisartan, 213 to indapamide and 230 to placebo. After the 3-year intervention, blood pressure was lower in the telmisartan and indapamide groups (P<0.05), FPG in the telmisartan group was lower during the first 2 years (P<0.05) and no characteristic differences were found in those with abdominal obesity among the three groups (P>0.05). The percentage of subjects with metabolic syndrome was significantly decreased in the telmisartan and indapamide groups (P<0.05), but was only significantly decreased in the telmisartan group for subjects with abdominal obesity (P<0.05). The acquisition cost for telmisartan was ~1.86 times higher than for indapamide for a similar antihypertensive effect. The intervention for high-normal blood pressure with telmisartan and indapamide appeared to be feasible and reduced the risk of metabolic syndrome. Telmisartan was more effective, whereas indapamide had better pharmacoeconomic benefits.

Impact of effective versus sham continuous positive airway pressure on liver injury in obstructive sleep apnoea: Data from randomized trials.

PubMed

Jullian-Desayes, Ingrid; Tamisier, Renaud; Zarski, Jean-Pierre; Aron-Wisnewsky, Judith; Launois-Rollinat, Sandrine H; Trocme, Candice; Levy, Patrick; Joyeux-Faure, Marie; Pepin, Jean-Louis

2016-02-01

Obstructive sleep apnoea (OSA) could be an independent risk factor for non-alcoholic fatty liver disease (NAFLD) occurrence and progression. The impact of continuous positive airway pressure (CPAP) treatment on non-invasive markers of NAFLD has not been studied. The aim of this study was to evaluate the effect of 6-12 weeks of effective CPAP on the FibroMax test (comprising components including the SteatoTest, NashTest and FibroTest) through three randomized sham controlled studies. The FibroMax test was performed in 103 obstructive sleep apnoea patients (apnoea + hypopnoea index > 15/h) enrolled in a randomized study comparing sham versus effective CPAP. At baseline, 40.4% of patients in the sham CPAP group and 45.5% in the CPAP group exhibited liver steatosis. Furthermore, 39.6% of patients in the sham CPAP group and 58.4% in the CPAP group displayed borderline or possible non-alcoholic steatohepatitis (NASH). Six to twelve weeks of effective CPAP did not demonstrate any impact on reducing steatosis, NASH or liver fibrosis even after adjustment for gender, BMI, baseline apnoea + hypopnoea index and severity of liver injury. A number of non-invasive markers of liver damage are increased in untreated obstructive sleep apnoea patients, potentially contributing to cardiometabolic risk, but they do not improve after 6-12 weeks of effective CPAP treatment. NCT01196845 (ADISAS), NCT00464659 (MneSAS) and NCT00669695 (StatinflaSAS) at ClinicalTrials.gov. © 2015 Asian Pacific Society of Respirology.

Interviewer effects on non-response propensity in longitudinal surveys: a multilevel modelling approach

PubMed Central

Vassallo, Rebecca; Durrant, Gabriele B; Smith, Peter W F; Goldstein, Harvey

2015-01-01

The paper investigates two different multilevel approaches, the multilevel cross-classified and the multiple-membership models, for the analysis of interviewer effects on wave non-response in longitudinal surveys. The models proposed incorporate both interviewer and area effects to account for the non-hierarchical structure, the influence of potentially more than one interviewer across waves and possible confounding of area and interviewer effects arising from the non-random allocation of interviewers across areas. The methods are compared by using a data set: the UK Family and Children Survey. PMID:25598587

A stochastic-geometric model of soil variation in Pleistocene patterned ground

NASA Astrophysics Data System (ADS)

Lark, Murray; Meerschman, Eef; Van Meirvenne, Marc

2013-04-01

In this paper we examine the spatial variability of soil in parent material with complex spatial structure which arises from complex non-linear geomorphic processes. We show that this variability can be better-modelled by a stochastic-geometric model than by a standard Gaussian random field. The benefits of the new model are seen in the reproduction of features of the target variable which influence processes like water movement and pollutant dispersal. Complex non-linear processes in the soil give rise to properties with non-Gaussian distributions. Even under a transformation to approximate marginal normality, such variables may have a more complex spatial structure than the Gaussian random field model of geostatistics can accommodate. In particular the extent to which extreme values of the variable are connected in spatially coherent regions may be misrepresented. As a result, for example, geostatistical simulation generally fails to reproduce the pathways for preferential flow in an environment where coarse infill of former fluvial channels or coarse alluvium of braided streams creates pathways for rapid movement of water. Multiple point geostatistics has been developed to deal with this problem. Multiple point methods proceed by sampling from a set of training images which can be assumed to reproduce the non-Gaussian behaviour of the target variable. The challenge is to identify appropriate sources of such images. In this paper we consider a mode of soil variation in which the soil varies continuously, exhibiting short-range lateral trends induced by local effects of the factors of soil formation which vary across the region of interest in an unpredictable way. The trends in soil variation are therefore only apparent locally, and the soil variation at regional scale appears random. We propose a stochastic-geometric model for this mode of soil variation called the Continuous Local Trend (CLT) model. We consider a case study of soil formed in relict patterned ground with pronounced lateral textural variations arising from the presence of infilled ice-wedges of Pleistocene origin. We show how knowledge of the pedogenetic processes in this environment, along with some simple descriptive statistics, can be used to select and fit a CLT model for the apparent electrical conductivity (ECa) of the soil. We use the model to simulate realizations of the CLT process, and compare these with realizations of a fitted Gaussian random field. We show how statistics that summarize the spatial coherence of regions with small values of ECa, which are expected to have coarse texture and so larger saturated hydraulic conductivity, are better reproduced by the CLT model than by the Gaussian random field. This suggests that the CLT model could be used to generate an unlimited supply of training images to allow multiple point geostatistical simulation or prediction of this or similar variables.

Experimental sleep restriction causes endothelial dysfunction in healthy humans.

PubMed

Calvin, Andrew D; Covassin, Naima; Kremers, Walter K; Adachi, Taro; Macedo, Paula; Albuquerque, Felipe N; Bukartyk, Jan; Davison, Diane E; Levine, James A; Singh, Prachi; Wang, Shihan; Somers, Virend K

2014-11-25

Epidemiologic evidence suggests a link between short sleep duration and cardiovascular risk, although the nature of any relationship and mechanisms remain unclear. Short sleep duration has also been linked to an increase in cardiovascular events. Endothelial dysfunction has itself been implicated as a mediator of heightened cardiovascular risk. We sought to determine the effect of 8 days/8 nights of partial sleep restriction on endothelial function in healthy humans. Sixteen healthy volunteers underwent a randomized study of usual sleep versus sleep restriction of two-thirds normal sleep time for 8 days/8 nights in a hospital-based clinical research unit. The main outcome was endothelial function measured by flow-mediated brachial artery vasodilatation (FMD). Those randomized to sleep restriction slept 5.1 hours/night during the experimental period compared with 6.9 hours/night in the control group. Sleep restriction was associated with significant impairment in FMD (8.6±4.6% during the initial pre-randomization acclimation phase versus 5.2±3.4% during the randomized experimental phase, P=0.01) whereas no change was seen in the control group (5.0±3.0 during the acclimation phase versus 6.73±2.9% during the experimental phase, P=0.10) for a between-groups difference of -4.40% (95% CI -7.00 to -1.81%, P=0.003). No change was seen in non-flow mediated vasodilatation (NFMD) in either group. In healthy individuals, moderate sleep restriction causes endothelial dysfunction. ClinicalTrials.gov. Unique identifier: NCT01334788. © 2014 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

Mesoscopic description of random walks on combs

NASA Astrophysics Data System (ADS)

Méndez, Vicenç; Iomin, Alexander; Campos, Daniel; Horsthemke, Werner

2015-12-01

Combs are a simple caricature of various types of natural branched structures, which belong to the category of loopless graphs and consist of a backbone and branches. We study continuous time random walks on combs and present a generic method to obtain their transport properties. The random walk along the branches may be biased, and we account for the effect of the branches by renormalizing the waiting time probability distribution function for the motion along the backbone. We analyze the overall diffusion properties along the backbone and find normal diffusion, anomalous diffusion, and stochastic localization (diffusion failure), respectively, depending on the characteristics of the continuous time random walk along the branches, and compare our analytical results with stochastic simulations.

SPINAL AND PERIPHERAL DRY NEEDLING VERSUS PERIPHERAL DRY NEEDLING ALONE AMONG INDIVIDUALS WITH A HISTORY OF LATERAL ANKLE SPRAIN: A RANDOMIZED CONTROLLED TRIAL

PubMed Central

Rossi, Ainsley; Blaustein, Sara; Brown, Joshua; Dieffenderfer, Kari; Ervin, Elaine; Griffin, Steven; Frierson, Elizabeth; Geist, Kathleen

2017-01-01

Background In addition to established interventions, dry needling may reduce impairments leading to greater functional abilities for individuals following ankle sprain. Hypothesis/Purpose The purpose of this study was to compare effects of spinal and peripheral dry needling (DN) with peripheral DN alone on impairments and functional performance among individuals with a history of lateral ankle sprain. Study Design Randomized controlled trial. Methods Twenty individuals with a history of lateral ankle sprain (18 bilateral, 2 unilateral) participated in this study (4 males, 16 females; mean age 28.9 + /- 9.2 years). During the first of two sessions, participants completed the Foot and Ankle Disability Index (FADI) and the Cumberland Ankle Instability Tool (CAIT) and their strength, unilateral balance, and unilateral hop test performance was assessed. Participants were randomly assigned to a spinal and peripheral DN group (SPDN), or a peripheral only DN group (PDN). Participants in the SPDN site group received DN to bilateral L5 multifidi and fibularis longus and brevis muscles on the involved lower extremity. Participants in the PDN group received DN to the fibularis muscles alone. Participants’ strength, balance and hop test performance were reassessed immediately following the intervention, and at follow-up 6-7 days later, all outcome measures were reassessed. Three-way mixed model ANOVAs and Mann-Whitney U tests assessed between group differences for outcome variables with normal distributions and non-normal distributions, respectively. Results ANOVAs showed significant group by time interaction (p<0.05) for invertor strength, significant side by group and time by group interactions (p<0.05) for plantarflexor-evertor strength, no significant findings for dorsiflexor-invertor strength, significant side by time interaction (p<0.05) for unilateral balance, significant main effect of time (p<0.05) for triple hop for distance test, and significant main effect of side (p<0.05) for the CAIT. Mann-Whitney U tests showed no significance (p>0.05) for the side hop test or FADI. Conclusion The results suggest that DN of the multifidi in addition to fibularis muscles does not result in improvements in strength, unilateral balance or unilateral hop test performance, compared to DN the fibularis muscles alone among individuals with a history of ankle sprain. PMID:29234555

Does increased exercise or physical activity alter ad-libitum daily energy intake or macronutrient composition in healthy adults? A systematic review.

PubMed

Donnelly, Joseph E; Herrmann, Stephen D; Lambourne, Kate; Szabo, Amanda N; Honas, Jeffery J; Washburn, Richard A

2014-01-01

The magnitude of the negative energy balance induced by exercise may be reduced due to compensatory increases in energy intake. TO ADDRESS THE QUESTION: Does increased exercise or physical activity alter ad-libitum daily energy intake or macronutrient composition in healthy adults? PubMed and Embase were searched (January 1990-January 2013) for studies that presented data on energy and/or macronutrient intake by level of exercise, physical activity or change in response to exercise. Ninety-nine articles (103 studies) were included. Primary source articles published in English in peer-reviewed journals. Articles that presented data on energy and/or macronutrient intake by level of exercise or physical activity or changes in energy or macronutrient intake in response to acute exercise or exercise training in healthy (non-athlete) adults (mean age 18-64 years). Articles were grouped by study design: cross-sectional, acute/short term, non-randomized, and randomized trials. Considerable heterogeneity existed within study groups for several important study parameters, therefore a meta-analysis was considered inappropriate. Results were synthesized and presented by study design. No effect of physical activity, exercise or exercise training on energy intake was shown in 59% of cross-sectional studies (n = 17), 69% of acute (n = 40), 50% of short-term (n = 10), 92% of non-randomized (n = 12) and 75% of randomized trials (n = 24). Ninety-four percent of acute, 57% of short-term, 100% of non-randomized and 74% of randomized trials found no effect of exercise on macronutrient intake. Forty-six percent of cross-sectional trials found lower fat intake with increased physical activity. The literature is limited by the lack of adequately powered trials of sufficient duration, which have prescribed and measured exercise energy expenditure, or employed adequate assessment methods for energy and macronutrient intake. We found no consistent evidence that increased physical activity or exercise effects energy or macronutrient intake.

Recruitment to and pilot results of the PACES randomized trial of physical exercise during adjuvant chemotherapy for colon cancer.

PubMed

van Waart, Hanna; Stuiver, Martijn M; van Harten, Wim H; Geleijn, Edwin; de Maaker-Berkhof, Marianne; Schrama, Jolanda; Geenen, Maud M; Meerum Terwogt, Jetske M; van den Heiligenberg, Simone M; Hellendoorn-van Vreeswijk, Jeannette A J H; Sonke, Gabe S; Aaronson, Neil K

2018-01-01

We report the recruitment rate, reasons for and factors influencing non-participation, and descriptive results of a randomized controlled trial of two different exercise programs for patients with colon cancer undergoing adjuvant chemotherapy. Participants were randomized to a low-intensity, home-based program (Onco-Move), a moderate- to high-intensity, combined supervised resistance and aerobic exercise program (OnTrack), or Usual Care. Non-participants provided reasons for non-participation and were asked to complete a questionnaire assessing behavioral and attitudinal variables. Trial participants completed performance-based and self-reported outcome measures prior to randomization, at the end of chemotherapy, and at the 6-month follow-up. Twenty-three of 63 referred patients agreed to participate in the trial. All 40 non-participants provided reasons for non-participation. Forty-five percent of the non-participants completed the questionnaire. Those who did not want to exercise had higher fatigue scores at baseline and a more negative attitude toward exercise. Compliance to both programs was high and no adverse events occurred. On average, the colon cancer participants were able to maintain or improve their physical fitness levels and maintain or decrease their fatigue levels during chemotherapy and follow-up. Recruitment of patients with colon cancer to a physical exercise trial during adjuvant chemotherapy proved to be difficult, underscoring the need to develop more effective strategies to increase participation rates. Both home-based and supervised programs are safe and feasible in patients with colon cancer undergoing chemotherapy. Effectiveness needs to be established in a larger trial. Netherlands Trial Register - NTR2159.

Identifying the Average Causal Mediation Effects with Multiple Mediators in the Presence of Treatment Non-Compliance

ERIC Educational Resources Information Center

Park, Soojin

2015-01-01

Identifying the causal mechanisms is becoming more essential in social and medical sciences. In the presence of treatment non-compliance, the Intent-To-Treated effect (hereafter, ITT effect) is identified as long as the treatment is randomized (Angrist et al., 1996). However, the mediated portion of effect is not identified without additional…

Effect of periodontal therapy on pregnancy outcome in women affected by periodontitis.

PubMed

Tarannum, Fouzia; Faizuddin, Mohamed

2007-11-01

There is convincing evidence to suggest that infections affecting the mother during pregnancy may produce alterations in the normal cytokine- and hormone-regulated gestation, which could result in preterm labor, premature rupture of membranes, and preterm birth (PTB). Studies in the late 1990s associated periodontitis with preterm low birth weight (PLBW) deliveries, and this may have similar pathogenic mechanisms as other maternal infections. This study determined the effect of non-surgical periodontal therapy on pregnancy outcome. A total of 200 pregnant women with periodontitis were randomly assigned to treatment and control groups. Detailed data about previous and current pregnancies were obtained. All women received a full-mouth periodontal examination, including oral hygiene index-simplified, bleeding index, and clinical attachment level. The women in the treatment group received non-surgical periodontal therapy during the gestational period, and those in the control group received periodontal treatment after delivery. Periodontal therapy included plaque control instructions and scaling and root planing performed under local anesthesia. The outcome measures assessed were gestational age and birth weight of the infant. PTB was recorded when delivery occurred at <37 weeks of gestation, and low birth weight (LBW) was recorded when the infant weighed<2,500 g. There were 53 PTBs in the treatment group and 68 PTBs in the control group. Twenty-six LBW infants were recorded in the treatment group, and 48 LBW infants were noted in the control group. The mean gestational ages were 33.8+/-2.8 weeks and 32.7+/-2.8 weeks in the treatment and control groups, respectively. The difference was statistically significant at P<0.006. The mean birth weight was 2,565.3+/-331.2 g in the treatment group and 2,459.6+/-380.7 g in the control group, with the difference being statistically significant at P<0.044. A multiple regression model showed a significant effect of periodontal treatment on birth outcomes. Non-surgical periodontal therapy can reduce the risk for preterm births in mothers who are affected by periodontitis. Additional multicentered, randomized, controlled clinical trials are required to confirm this link between periodontitis and PLBW.

Orbital Anomalies in Goddard Spacecraft for Calendar Year 1994

NASA Technical Reports Server (NTRS)

Thomas, Walter B.

1996-01-01

This report summarizes and updates the annual on-orbit performance between January I and December 31, 1994, for spacecraft built by or managed by the Goddard Space Flight Center (GSFC). During 1994, GSFC had 27 active orbiting satellites and I Shuttle-launched and retrieved 'free flyer.' There were 310 reported anomalies among 21 satellites and one GSFC instrument (TOMS). GOES-8 accounted for 66 anomalies, and SAMPES reported 155 'anomalies'. Of the 155 anomalies reported for all but SAMPEX, only 4 affected the spacecraft missions 'substantially' or greater, that is, presented a loss of more than 33% of the total missions. The most frequent subsystem anomalies were Instrument/Payload(44), Timing Command and Control(40), and Attitude Control Systems(33). Of the non-SAMPEX anomalies, 29% had no effect on the missions and 28% caused subsystem or instrument degradation and, for another 28%, no anomaly effect on the mission could be determined. Fifty-three percent of non-SAMPEX anomalies could not be classified according to 'type'; the other most common types were 'systemic'(35), 'random'(19), and 'normal or expected operation'(15). Forty percent of the anomalies were not classified according to failure category; the remaining most frequent occurrences were 'design problems'(50) and 'other known problems'(35).

Effects of an implantable two-channel peroneal nerve stimulator versus conventional walking device on spatiotemporal parameters and kinematics of hemiparetic gait.

PubMed

Kottink, Anke I R; Tenniglo, Martin J B; de Vries, Wiebe H K; Hermens, Hermie J; Buurke, Jaap H

2012-01-01

The aims of this study were: (i) to compare the neuro-prosthetic effect of implantable peroneal nerve stimulation to the orthotic effect of a standard of care intervention (no device, shoe or ankle foot orthosis) on walking, as assessed by spatiotemporal parameters; and (ii) to examine whether there is evidence of an enhanced lower-limb flexion reflex with peroneal nerve stimulation and compare the kinematic effect of an implantable peroneal nerve stimulation device vs standard of care intervention on initial loading response of the paretic limb, as assessed by hip, knee and ankle kinematics. Randomized controlled trial. A total of 23 chronic stroke survivors with drop foot. The intervention group received an implantable 2-channel peroneal nerve stimulator for correction of drop foot. The control group continued using a conventional walking device. Spatiotemporal parameters and hip, knee and ankle kinematics were measured while subjects walked with the device on using a 3-dimensional video camera system during baseline and after a follow-up period of 26 weeks. Peroneal nerve stimulation normalized stance and double support of the paretic limb and single support of the non-paretic limb, in comparison with using a conventional walking device. In addition, peroneal nerve stimulation is more effective to provide ankle dorsiflexion during swing and resulted in a normalized initial loading response. Although peroneal nerve stimulation and ankle foot orthosis are both prescribed to correct a drop foot in the same patient population, spatiotemporal parameters, dorsiflexion during swing and loading response are influenced in a functionally different way.

Effect of peer support interventions on cardiovascular disease risk factors in adults with diabetes: a systematic review and meta-analysis.

PubMed

Patil, Sonal J; Ruppar, Todd; Koopman, Richelle J; Lindbloom, Erik J; Elliott, Susan G; Mehr, David R; Conn, Vicki S

2018-03-23

Peer support by persons affected with diabetes improves peer supporter's diabetes self-management skills. Peer support interventions by individuals who have diabetes or are affected by diabetes have been shown to improve glycemic control; however, its effects on other cardiovascular disease risk factors in adults with diabetes are unknown. We aimed to estimate the effect of peer support interventions on cardiovascular disease risk factors other than glycemic control in adults with diabetes. We conducted a systematic review and meta-analysis of randomized controlled trials comparing peer support interventions to a control condition in adults affected by diabetes that measured any cardiovascular disease risk factors [Body Mass Index, smoking, diet, physical activity, cholesterol level, glucose control and blood pressure]. Quality was assessed by Cochrane's risk of bias tool. We calculated standardized mean difference effect sizes using random effects models. We retrieved 438 citations from multiple databases including OVID MEDLINE, Cochrane database and Scopus, and author searches. Of 233 abstracts reviewed, 16 articles met inclusion criteria. A random effects model in a total of 3243 participants showed a positive effect of peer support interventions on systolic BP with a pooled effect size of 2.07 mmHg (CI 0.35 mmHg to 3.79 mmHg, p = 0.02); baseline pooled systolic blood pressure was 137 mmHg. There was a non-significant effect of peer support interventions on diastolic blood pressure, cholesterol, body mass index, diet and physical activity. Cardiovascular disease risk factors other than glycemic control outcomes were secondary outcomes in most studies and baseline values were normal or mildly elevated. Only one study reported smoking outcomes. We found a small (2 mmHg) positive effect of peer support interventions on systolic blood pressure in adults with diabetes whose baseline blood pressure was on average minimally elevated. Additional studies need to be conducted to further understand the effect of peer support interventions on high-risk cardiovascular disease risk factors in adults with diabetes.

Efficacy of a modern neuroscience approach versus usual care evidence-based physiotherapy on pain, disability and brain characteristics in chronic spinal pain patients: protocol of a randomized clinical trial

PubMed Central

2014-01-01

Background Among the multiple conservative modalities, physiotherapy is a commonly utilized treatment modality in managing chronic non-specific spinal pain. Despite the scientific progresses with regard to pain and motor control neuroscience, treatment of chronic spinal pain (CSP) often tends to stick to a peripheral biomechanical model, without targeting brain mechanisms. With a view to enhance clinical efficacy of existing physiotherapeutic treatments for CSP, the development of clinical strategies targeted at ‘training the brain’ is to be pursued. Promising proof-of-principle results have been reported for the effectiveness of a modern neuroscience approach to CSP when compared to usual care, but confirmation is required in a larger, multi-center trial with appropriate evidence-based control intervention and long-term follow-up. The aim of this study is to assess the effectiveness of a modern neuroscience approach, compared to usual care evidence-based physiotherapy, for reducing pain and improving functioning in patients with CSP. A secondary objective entails examining the effectiveness of the modern neuroscience approach versus usual care physiotherapy for normalizing brain gray matter in patients with CSP. Methods/Design The study is a multi-center, triple-blind, two-arm (1:1) randomized clinical trial with 1-year follow-up. 120 CSP patients will be randomly allocated to either the experimental (receiving pain neuroscience education followed by cognition-targeted motor control training) or the control group (receiving usual care physiotherapy), each comprising of 3 months treatment. The main outcome measures are pain (including symptoms and indices of central sensitization) and self-reported disability. Secondary outcome measures include brain gray matter structure, motor control, muscle properties, and psychosocial correlates. Clinical assessment and brain imaging will be performed at baseline, post-treatment and at 1-year follow-up. Web-based questionnaires will be completed at baseline, after the first 3 treatment sessions, post-treatment, and at 6 and 12-months follow-up. Discussion Findings may provide empirical evidence on: (1) the effectiveness of a modern neuroscience approach to CSP for reducing pain and improving functioning, (2) the effectiveness of a modern neuroscience approach for normalizing brain gray matter in CSP patients, and (3) factors associated with therapy success. Hence, this trial might contribute towards refining guidelines for good clinical practice and might be used as a basis for health authorities’ recommendations. Trial registration ClinicalTrials.gov Identifier: NCT02098005. PMID:24885889

Assessing the quality of a non-randomized pragmatic trial for primary prevention of falls among older adults.

PubMed

Albert, Steven M; Edelstein, Offer; King, Jennifer; Flatt, Jason; Lin, Chyongchiou J; Boudreau, Robert; Newman, Anne B

2015-01-01

Current approaches to falls prevention mostly rely on secondary and tertiary prevention and target individuals at high risk of falls. An alternative is primary prevention, in which all seniors are screened, referred as appropriate, and educated regarding falls risk. Little information is available on research designs that allow investigation of this approach in the setting of aging services delivery, where randomization may not be possible. Healthy Steps for Older Adults, a statewide program of the Pennsylvania (PA) Department of Aging, involves a combination of education about falls and screening for balance problems, with referral to personal physicians and home safety assessments. We developed a non-randomized statewide trial, Falls Free PA, to assess its effectiveness in reducing falls incidence over 12 months. We recruited 814 seniors who completed the program (503 first-time participants, 311 people repeating the program) and 1,020 who did not participate in the program, from the same sites. We assessed the quality of this non-randomized design by examining recruitment, follow-up across study groups, and comparability at baseline. Of older adults approached in senior centers, 90.5 % (n = 2,219) signed informed consent, and 1,834 (82.4 %) completed baseline assessments and were eligible for follow-up. Attrition in the three groups over 12 months was low and non-differential (<10 % for withdrawal and <2 % for other loss to follow-up). Median follow-up, which involved standardized monthly assessment of falls, was 10 months in all study groups. At baseline, the groups did not differ in measures of health or falls risk factors. Comparable status at baseline, recruitment from common sites, and similar experience with retention suggest that the non-randomized design will be effective for assessment of this approach to primary prevention of falls.

Case-based or non-case-based questions for teaching postgraduate physicians: a randomized crossover trial.

PubMed

Cook, David A; Thompson, Warren G; Thomas, Kris G

2009-10-01

The comparative efficacy of case-based (CB) and non-CB self-assessment questions in Web-based instruction is unknown. The authors sought to compare CB and non-CB questions. The authors conducted a randomized crossover trial in the continuity clinics of two academic residency programs. Four Web-based modules on ambulatory medicine were developed in both CB (periodic questions based on patient scenarios) and non-CB (questions matched for content but lacking patient scenarios) formats. Participants completed two modules in each format (sequence randomly assigned). Participants also completed a pretest of applied knowledge for two modules (randomly assigned). For the 130 participating internal medicine and family medicine residents, knowledge scores improved significantly (P < .0001) from pretest (mean: 53.5; SE: 1.1) to posttest (75.1; SE: 0.7). Posttest knowledge scores were similar in CB (75.0; SE: 0.1) and non-CB formats (74.7; SE: 1.1); the 95% CI was -1.6, 2.2 (P = .76). A nearly significant (P = .062) interaction between format and the presence or absence of pretest suggested a differential effect of question format, depending on pretest. Overall, those taking pretests had higher posttest knowledge scores (76.7; SE: 1.1) than did those not taking pretests (73.0; SE: 1.1; 95% CI: 1.7, 5.6; P = .0003). Learners preferred the CB format. Time required was similar (CB: 42.5; SE: 1.8 minutes, non-CB: 40.9; SE: 1.8 minutes; P = .22). Our findings suggest that, among postgraduate physicians, CB and non-CB questions have similar effects on knowledge scores, but learners prefer CB questions. Pretests influence posttest scores.

The Effect of COX-2 Inhibitors on the Aromatase Gene (CYP19) Expression in Human Breast Cancer

DTIC Science & Technology

2006-12-01

drug is it is associated with less side effects than non - steroidal inflammatory drugs ( NSAIDs ), particularly gastroduodenal ulcers. Randomized...Nested case-control study of effects of non - steroidal anti - inflammatory drugs on breast cancer risk and stage. B J Cancer 2000;83:112-120. 18...another non - steroidal anti - inflammatory ; 1 was determined to need neoadjuvant chemotherapy; 1 had a benign core biopsy, and 2

The metabolic and endocrine response and health implications of consuming sugar-sweetened beverages: findings from recent randomized controlled trials.

PubMed

Rippe, James M

2013-11-01

Fructose-containing sugars, including fructose itself, high fructose corn syrup (HFCS), and sucrose have engendered considerable controversy. The effects of HFCS and sucrose in sugar-sweetened beverages, in particular, have generated intense scientific debate that has spilled over to the public. This controversy is related to well-known differences in metabolism between fructose and glucose in the liver. In addition, research studies have often been conducted comparing pure fructose and pure glucose even though neither is consumed to any appreciable degree in isolation in the human diet. Other evidence has been drawn from animal studies and epidemiologic or cohort studies. Few randomized controlled trials (RCTs) have compared HFCS with sucrose (the 2 sugars most commonly consumed in the human diet) at dosage amounts within the normal human consumption range. This review compares results of recently concluded RCTs with other forms of evidence related to fructose, HFCS, and sucrose. We conclude that great caution must be used when suggesting adverse health effects of consuming these sugars in the normal way they are consumed and at the normal amounts in the human diet, because RCTs do not support adverse health consequences at these doses when employing these sugars.

Studying the Polarization Switching in Polycrystalline BiFeO3 Films by 2D Piezoresponse Force Microscopy

NASA Astrophysics Data System (ADS)

Jin, Yaming; Lu, Xiaomei; Zhang, Junting; Kan, Yi; Bo, Huifeng; Huang, Fengzhen; Xu, Tingting; Du, Yingchao; Xiao, Shuyu; Zhu, Jinsong

2015-07-01

For rhombohedral multiferroelectrics, non-180° ferroelectric domain switching may induce ferroelastic and/or (anti-)ferromagnetic effect. So the determination and control of ferroelectric domain switching angles is crucial for nonvolatile information storage and exchange-coupled magnetoelectric devices. We try to study the intrinsic characters of polarization switching in BiFeO3 by introducing a special data processing method to determine the switching angle from 2D PFM (Piezoresponse Force Microscopy) images of randomly oriented samples. The response surface of BiFeO3 is first plotted using the piezoelectric tensor got from first principles calculations. Then from the normalized 2D PFM signals before and after switching, the switching angles of randomly oriented BiFeO3 grains can be determined through numerical calculations. In the polycrystalline BiFeO3 films, up to 34% of all switched area is that with original out-of-plane (OP) polarization parallel to the poling field. 71° polarization switching is more favorable, with the area percentages of 71°, 109° and 180° domain switching being about 42%, 29% and 29%, respectively. Our analysis further reveals that IP stress and charge migration have comparable effect on switching, and they are sensitive to the geometric arrangements. This work helps exploring a route to control polarization switching in BiFeO3, so as to realize desirable magnetoelectric coupling.

Memantine Improves Attentional Processes in Fragile X-Associated Tremor/Ataxia Syndrome: Electrophysiological Evidence from a Randomized Controlled Trial.

PubMed

Yang, Jin-Chen; Rodriguez, Annette; Royston, Ashley; Niu, Yu-Qiong; Avar, Merve; Brill, Ryan; Simon, Christa; Grigsby, Jim; Hagerman, Randi J; Olichney, John M

2016-02-22

Progressive cognitive deficits are common in patients with fragile X-associated tremor/ataxia syndrome (FXTAS), with no targeted treatment yet established. In this substudy of the first randomized controlled trial for FXTAS, we examined the effects of NMDA antagonist memantine on attention and working memory. Data were analyzed for patients (24 in each arm) who completed both the primary memantine trial and two EEG recordings (at baseline and follow-up) using an auditory "oddball" task. Results demonstrated significantly improved attention/working memory performance after one year only for the memantine group. The event-related potential P2 amplitude elicited by non-targets was significantly enhanced in the treated group, indicating memantine-associated improvement in attentional processes at the stimulus identification/discrimination level. P2 amplitude increase was positively correlated with improvement on the behavioral measure of attention/working memory during target detection. Analysis also revealed that memantine treatment normalized the P2 habituation effect at the follow-up visit. These findings indicate that memantine may benefit attentional processes that represent fundamental components of executive function/dysfunction, thought to comprise the core cognitive deficit in FXTAS. The results provide evidence of target engagement of memantine, as well as therapeutically relevant information that could further the development of specific cognitive or disease-modifying therapies for FXTAS.

A Bayesian Model for the Estimation of Latent Interaction and Quadratic Effects When Latent Variables Are Non-Normally Distributed

ERIC Educational Resources Information Center

Kelava, Augustin; Nagengast, Benjamin

2012-01-01

Structural equation models with interaction and quadratic effects have become a standard tool for testing nonlinear hypotheses in the social sciences. Most of the current approaches assume normally distributed latent predictor variables. In this article, we present a Bayesian model for the estimation of latent nonlinear effects when the latent…

A computational model of oxygen transport in the cerebrocapillary levels for normal and pathologic brain function.

PubMed

Safaeian, Navid; David, Tim

2013-10-01

The oxygen exchange and correlation between the cerebral blood flow (CBF) and cerebral metabolic rate of oxygen consumption (CMRO2) in the cortical capillary levels for normal and pathologic brain functions remain the subject of debate. A 3D realistic mesoscale model of the cortical capillary network (non-tree like) is constructed using a random Voronoi tessellation in which each edge represents a capillary segment. The hemodynamics and oxygen transport are numerically simulated in the model, which involves rheological laws in the capillaries, oxygen diffusion, and non-linear binding of oxygen to hemoglobin, respectively. The findings show that the cerebral hypoxia due to a significant decreased perfusion (as can occur in stroke) can be avoided by a moderate reduction in oxygen demand. Oxygen extraction fraction (OEF) can be an important indicator for the brain oxygen metabolism under normal perfusion and misery-perfusion syndrome (leading to ischemia). The results demonstrated that a disproportionately large increase in blood supply is required for a small increase in the oxygen demand, which, in turn, is strongly dependent on the resting OEF. The predicted flow-metabolism coupling in the model supports the experimental studies of spatiotemporal stimulations in humans by positron emission tomography and functional magnetic resonance imaging.

A computational model of oxygen transport in the cerebrocapillary levels for normal and pathologic brain function

PubMed Central

Safaeian, Navid; David, Tim

2013-01-01

The oxygen exchange and correlation between the cerebral blood flow (CBF) and cerebral metabolic rate of oxygen consumption (CMRO2) in the cortical capillary levels for normal and pathologic brain functions remain the subject of debate. A 3D realistic mesoscale model of the cortical capillary network (non-tree like) is constructed using a random Voronoi tessellation in which each edge represents a capillary segment. The hemodynamics and oxygen transport are numerically simulated in the model, which involves rheological laws in the capillaries, oxygen diffusion, and non-linear binding of oxygen to hemoglobin, respectively. The findings show that the cerebral hypoxia due to a significant decreased perfusion (as can occur in stroke) can be avoided by a moderate reduction in oxygen demand. Oxygen extraction fraction (OEF) can be an important indicator for the brain oxygen metabolism under normal perfusion and misery-perfusion syndrome (leading to ischemia). The results demonstrated that a disproportionately large increase in blood supply is required for a small increase in the oxygen demand, which, in turn, is strongly dependent on the resting OEF. The predicted flow-metabolism coupling in the model supports the experimental studies of spatiotemporal stimulations in humans by positron emission tomography and functional magnetic resonance imaging. PMID:23921901

A Numerical Theory for Impedance Education in Three-Dimensional Normal Incidence Tubes

NASA Technical Reports Server (NTRS)

Watson, Willie R.; Jones, Michael G.

2016-01-01

A method for educing the locally-reacting acoustic impedance of a test sample mounted in a 3-D normal incidence impedance tube is presented and validated. The unique feature of the method is that the excitation frequency (or duct geometry) may be such that high-order duct modes may exist. The method educes the impedance, iteratively, by minimizing an objective function consisting of the difference between the measured and numerically computed acoustic pressure at preselected measurement points in the duct. The method is validated on planar and high-order mode sources with data synthesized from exact mode theory. These data are then subjected to random jitter to simulate the effects of measurement uncertainties on the educed impedance spectrum. The primary conclusions of the study are 1) Without random jitter the method is in excellent agreement with that for known impedance samples, and 2) Random jitter that is compatible to that found in a typical experiment has minimal impact on the accuracy of the educed impedance.

Surgical versus Non-Operative Treatment for Lumbar Disc Herniation: Eight-Year Results for the Spine Patient Outcomes Research Trial (SPORT)

PubMed Central

Lurie, Jon D.; Tosteson, Tor D.; Tosteson, Anna N. A.; Zhao, Wenyan; Morgan, Tamara S.; Abdu, William A.; Herkowitz, Harry; Weinstein, James N.

2014-01-01

Study Design Concurrent prospective randomized and observational cohort studies. Objective To assess the 8-year outcomes of surgery vs. non-operative care. Summary of Background Data Although randomized trials have demonstrated small short-term differences in favor of surgery, long-term outcomes comparing surgical to non-operative treatment remain controversial. Methods Surgical candidates with imaging-confirmed lumbar intervertebral disc herniation meeting SPORT eligibility criteria enrolled into prospective randomized (501 participants) and observational cohorts (743 participants) at 13 spine clinics in 11 US states. Interventions were standard open discectomy versus usual non-operative care. Main outcome measures were changes from baseline in the SF-36 Bodily Pain (BP) and Physical Function (PF) scales and the modified Oswestry Disability Index (ODI - AAOS/Modems version) assessed at 6 weeks, 3 and 6 months, and annually thereafter. Results Advantages were seen for surgery in intent-to-treat analyses for the randomized cohort for all primary and secondary outcomes other than work status; however, with extensive non-adherence to treatment assignment (49% patients assigned to non-operative therapy receiving surgery versus 60% of patients assigned to surgery) these observed effects were relatively small and not statistically significant for primary outcomes (BP, PF, ODI). Importantly, the overall comparison of secondary outcomes was significantly greater with surgery in the intent-to-treat analysis (sciatica bothersomeness [p > 0.005], satisfaction with symptoms [p > 0.013], and self-rated improvement [p > 0.013]) in long-term follow-up. An as-treated analysis showed clinically meaningful surgical treatment effects for primary outcome measures (mean change Surgery vs. Non-operative; treatment effect; 95% CI): BP (45.3 vs. 34.4; 10.9; 7.7 to 14); PF (42.2 vs. 31.5; 10.6; 7.7 to 13.5) and ODI (−36.2 vs. −24.8; −11.2; −13.6 to −9.1). Conclusion Carefully selected patients who underwent surgery for a lumbar disc herniation achieved greater improvement than non-operatively treated patients; there was little to no degradation of outcomes in either group (operative and non-operative) from 4 to 8 years. PMID:24153171

Dornase alpha compared to hypertonic saline for lung atelectasis in critically ill patients.

PubMed

Youness, Houssein A; Mathews, Kathryn; Elya, Marwan K; Kinasewitz, Gary T; Keddissi, Jean I

2012-12-01

Despite the lack of randomized trials, nebulized Dornase alpha and hypertonic saline are used empirically to treat atelectasis in mechanically ventilated patients. Our objective was to determine the clinical and radiological efficacy of these medications as an adjunct to standard therapy in critically ill patients. Mechanically ventilated patients with new onset (<48 h) lobar or multilobar atelectasis were randomized into three groups: nebulized Dornase alpha, hypertonic (7%) saline or normal saline every 12 h. All patients received standard therapy, including chest percussion therapy, kinetic therapy, and bronchodilators. The primary endpoint was the change in the daily chest X-ray atelectasis score. A total of 33 patients met the inclusion criteria and were randomized equally into the three groups. Patients in the Dornase alpha group showed a reduction of 2.18±1.33 points in the CXR score from baseline to day 7, whereas patients in the normal saline group had a reduction of 1.00±1.79 points, and patients in the hypertonic saline group showed a score reduction of 1.09±1.51 points. Pairwise comparison of the mean change of the CXR score showed no statistical difference between hypertonic saline, normal saline, and dornase alpha. Airway pressures as well as oxygenation, expressed as PaO(2)/F(I)O(2) and time to extubation also were similar among groups. During the study period the rate of extubation was 54% (6/11), 45% (5/11), and 63% (7/11) in the normal saline, hypertonic saline, and Dornase alpha groups, respectively (p=0.09). No treatment related complications were observed. There was no significant improvement in the chest X-ray atelectasis score in mechanically ventilated patients with new onset atelectasis who were nebulized with Dornase alpha twice a day. Hypertonic saline was no more effective than normal saline in this population. Larger randomized control trials are needed to confirm our results.

Spurious Latent Class Problem in the Mixed Rasch Model: A Comparison of Three Maximum Likelihood Estimation Methods under Different Ability Distributions

ERIC Educational Resources Information Center

Sen, Sedat

2018-01-01

Recent research has shown that over-extraction of latent classes can be observed in the Bayesian estimation of the mixed Rasch model when the distribution of ability is non-normal. This study examined the effect of non-normal ability distributions on the number of latent classes in the mixed Rasch model when estimated with maximum likelihood…

Effect of magnetic field on the flux pinning mechanisms in Al and SiC co-doped MgB2 superconductor

NASA Astrophysics Data System (ADS)

Kia, N. S.; Ghorbani, S. R.; Arabi, H.; Hossain, M. S. A.

2018-07-01

MgB2 superconductor samples co-doped with 0.02 wt. Al2O3 and 0-0.05 wt. SiC were studied by magnetization - magnetic field (M-H) loop measurements at different temperatures. The critical current density has been calculated by the Bean model, and the irreversibility field, Hirr, has been obtained by the Kramer method. The pinning mechanism of the co-doped sample with 2% Al and 5% SiC was investigated in particular due to its having the highest Hirr. The normalized volume pinning force f = F/Fmax as a function of reduced magnetic field h = H/Hirr has been obtained, and the pinning mechanism was studied by the Dew-Houghes model. It was found that the normal point pinning (NPP), the normal surface pinning (NSP), and the normal volume pinning (NVP) mechanisms play the main roles. The magnetic field and temperature dependence of contributions of the NPP, NSP, and NVP pinning mechanisms were obtained. The results show that the contributions of the pinning mechanisms depend on the temperature and magnetic field. From the temperature dependence of the critical current density within the collective pinning theory, it was found that both the δl pinning due to spatial fluctuations of the charge-carrier mean free path and the δTc pinning due to randomly distributed spatial variations in the transition temperature coexist at zero magnetic field in co-doped samples. Yet, the charge-carrier mean-free-path fluctuation pinning (δl) is the only important pinning mechanism at non-zero magnetic fields.

Systematic review of physiotherapy interventions to improve gross motor capacity and performance in children and adolescents with an acquired brain injury.

PubMed

Baque, Emmah; Sakzewski, Leanne; Barber, Lee; Boyd, Roslyn N

2016-01-01

To systematically review the efficacy of physiotherapy interventions to improve gross motor capacity, performance and societal participation in children aged 5-17 years with an acquired brain injury (ABI). Randomized and non-randomized controlled trials, cohort, case series, case-control and case studies were included and classified according to grades of evidence. Methodological quality of studies was assessed using the Downs and Black (D&B) scale and quantitative data was analysed using effect sizes. Two home-based studies investigated functional strength training (one randomized controlled trial, n = 20, level 2b, D&B = 16/32 and one non-randomized self-control study, n = 19, level 4, D&B = 15/32). Four studies evaluated virtual reality including: one pilot study, n = 50, level 4, D&B = 22/32; one single-subject, non-concurrent, randomized multiple baseline study, n = 3, level 4, D&B = 15/32; one case series study, n = 2, level 4, D&B = 15/32; one case study, n = 1, level 4, D&B = 15/32. Effect sizes for the randomized controlled trial ranged between 0.30-1.29 for the Functional Reach and Timed Up and Go outcome measures. There is preliminary evidence to support the efficacy of physiotherapy interventions to improve gross motor outcomes in children with an ABI. Both functional strength training and virtual-reality based therapy are potential treatment options for clinicians to prescribe in either home or clinical settings.

Variation of mutational burden in healthy human tissues suggests non-random strand segregation and allows measuring somatic mutation rates.

PubMed

Werner, Benjamin; Sottoriva, Andrea

2018-06-01

The immortal strand hypothesis poses that stem cells could produce differentiated progeny while conserving the original template strand, thus avoiding accumulating somatic mutations. However, quantitating the extent of non-random DNA strand segregation in human stem cells remains difficult in vivo. Here we show that the change of the mean and variance of the mutational burden with age in healthy human tissues allows estimating strand segregation probabilities and somatic mutation rates. We analysed deep sequencing data from healthy human colon, small intestine, liver, skin and brain. We found highly effective non-random DNA strand segregation in all adult tissues (mean strand segregation probability: 0.98, standard error bounds (0.97,0.99)). In contrast, non-random strand segregation efficiency is reduced to 0.87 (0.78,0.88) in neural tissue during early development, suggesting stem cell pool expansions due to symmetric self-renewal. Healthy somatic mutation rates differed across tissue types, ranging from 3.5 × 10-9/bp/division in small intestine to 1.6 × 10-7/bp/division in skin.

Automated feature extraction and spatial organization of seafloor pockmarks, Belfast Bay, Maine, USA

USGS Publications Warehouse

Andrews, Brian D.; Brothers, Laura L.; Barnhardt, Walter A.

2010-01-01

Seafloor pockmarks occur worldwide and may represent millions of m3 of continental shelf erosion, but few numerical analyses of their morphology and spatial distribution of pockmarks exist. We introduce a quantitative definition of pockmark morphology and, based on this definition, propose a three-step geomorphometric method to identify and extract pockmarks from high-resolution swath bathymetry. We apply this GIS-implemented approach to 25 km2 of bathymetry collected in the Belfast Bay, Maine USA pockmark field. Our model extracted 1767 pockmarks and found a linear pockmark depth-to-diameter ratio for pockmarks field-wide. Mean pockmark depth is 7.6 m and mean diameter is 84.8 m. Pockmark distribution is non-random, and nearly half of the field's pockmarks occur in chains. The most prominent chains are oriented semi-normal to the steepest gradient in Holocene sediment thickness. A descriptive model yields field-wide spatial statistics indicating that pockmarks are distributed in non-random clusters. Results enable quantitative comparison of pockmarks in fields worldwide as well as similar concave features, such as impact craters, dolines, or salt pools.

Non-continuum, anisotropic nanomechanics of random and aligned electrospun nanofiber matrices

NASA Astrophysics Data System (ADS)

Chery, Daphney; Han, Biao; Mauck, Robert; Shenoy, Vivek; Han, Lin

Polymer nanofiber assemblies are widely used in cell culture and tissue engineering, while their nanomechanical characteristics have received little attention. In this study, to understand their nanoscale structure-mechanics relations, nanofibers of polycaprolactone (PCL) and poly(vinyl alcohol) (PVA) were fabricated via electrospinning, and tested via AFM-nanoindentation with a microspherical tip (R ~10 μm) in PBS. For the hydrophobic, less-swollen PCL, a novel, non-continuum linear F-D dependence was observed, instead of the typical Hertzian F-D3/2 behavior, which is usually expected for continuum materials. This linear trend is likely resulted from the tensile stretch of a few individual nanofibers as they were indented in the normal plane. In contrast, for the hydrophilic, highly swollen PVA, the observed typical Hertzian response indicates the dominance of localized deformation within each nanofiber, which had swollen to become hydrogels. Furthermore, for both matrices, aligned fibers showed significantly higher stiffness than random fibers. These results provide a fundamental basis on the nanomechanics of biomaterials for specialized applications in cell phenotype and tissue repair.

Surgery for congenital choanal atresia.

PubMed

Cedin, Antonio C; Atallah, Alvaro N; Andriolo, Régis B; Cruz, Oswaldo L; Pignatari, Shirley N

2012-02-15

Congenital choanal atresia is a rare abnormality characterized by unilateral or bilateral lack of patency of the posterior end of the nasal cavity. With an incidence of 1:5000 to 1:8000 births, it is twice as prevalent in females as it is in males. Surgical procedures aim to provide adequate functional choanal patency and a low rate of restenosis, avoid harm to any structure in development, enable shorter surgery and hospitalization times, and minimize morbidity and mortality. To evaluate the effectiveness and safety of the available surgical techniques for the treatment of congenital choanal atresia in patients with unilateral and bilateral atresia. We searched the Cochrane Ear, Nose and Throat Disorders Group Trials Register; the Cochrane Central Register of Controlled Trials (CENTRAL); PubMed; EMBASE; CINAHL; Web of Science; BIOSIS Previews; Cambridge Scientific Abstracts; ISRCTN and additional sources for published and unpublished trials. The date of the search was 31 January 2011. We planned to include parallel randomized or quasi-randomized controlled trials testing surgical approaches for the treatment of congenital atresia (irrespective of gender and age) that evaluated normal/adequate respiratory function (self reported or preserved nasal airway) and restenosis as the main primary outcomes. We did not consider reoperation and non-congenital atresia (e.g. traumatic, iatrogenic atresias) for inclusion. Three review authors independently assessed the titles and abstracts of the identified articles to determine potential relevance. For dichotomous and continuous variables, we planned to calculate risk ratios (relative risks; RR) and mean differences (MD) with 95% confidence intervals (CI), respectively. We planned to use the random-effects model since we were expecting substantial clinical and methodological heterogeneity. No randomized controlled trials were identified. From the 120 reports retrieved using our search strategy, 46 primary studies had the potential to be included since they had tested surgical approaches for choanal atresia. However, we excluded all of them during the final selection process because their study designs did not meet our inclusion criteria. There is no definitive evidence, based on randomized controlled trials, to demonstrate the potential advantages and disadvantages of any specific surgical technique for patients with choanal atresia. Specialists should unify their efforts in multicenter randomized controlled trials that test the effectiveness and safety of different surgical techniques in patients with choanal atresia.

Dimension Reduction With Extreme Learning Machine.

PubMed

Kasun, Liyanaarachchi Lekamalage Chamara; Yang, Yan; Huang, Guang-Bin; Zhang, Zhengyou

2016-08-01

Data may often contain noise or irrelevant information, which negatively affect the generalization capability of machine learning algorithms. The objective of dimension reduction algorithms, such as principal component analysis (PCA), non-negative matrix factorization (NMF), random projection (RP), and auto-encoder (AE), is to reduce the noise or irrelevant information of the data. The features of PCA (eigenvectors) and linear AE are not able to represent data as parts (e.g. nose in a face image). On the other hand, NMF and non-linear AE are maimed by slow learning speed and RP only represents a subspace of original data. This paper introduces a dimension reduction framework which to some extend represents data as parts, has fast learning speed, and learns the between-class scatter subspace. To this end, this paper investigates a linear and non-linear dimension reduction framework referred to as extreme learning machine AE (ELM-AE) and sparse ELM-AE (SELM-AE). In contrast to tied weight AE, the hidden neurons in ELM-AE and SELM-AE need not be tuned, and their parameters (e.g, input weights in additive neurons) are initialized using orthogonal and sparse random weights, respectively. Experimental results on USPS handwritten digit recognition data set, CIFAR-10 object recognition, and NORB object recognition data set show the efficacy of linear and non-linear ELM-AE and SELM-AE in terms of discriminative capability, sparsity, training time, and normalized mean square error.

Gradual Crossover from Subdiffusion to Normal Diffusion: A Many-Body Effect in Protein Surface Water

NASA Astrophysics Data System (ADS)

Tan, Pan; Liang, Yihao; Xu, Qin; Mamontov, Eugene; Li, Jinglai; Xing, Xiangjun; Hong, Liang

2018-06-01

Dynamics of hydration water is essential for the function of biomacromolecules. Previous studies have demonstrated that water molecules exhibit subdiffusion on the surface of biomacromolecules; yet the microscopic mechanism remains vague. Here, by performing neutron scattering, molecular dynamics simulations, and analytic modeling on hydrated perdeuterated protein powders, we found water molecules jump randomly between trapping sites on protein surfaces, whose waiting times obey a broad distribution, resulting in subdiffusion. Moreover, the subdiffusive exponent gradually increases with observation time towards normal diffusion due to a many-body volume-exclusion effect.

Pravastatin and endothelium dependent vasomotion after coronary angioplasty: the PREFACE trial.

PubMed

Mulder, H J; Schalij, M J; Kauer, B; Visser, R F; van Dijkman, P R; Jukema, J W; Zwinderman, A H; Bruschke, A V

2001-11-01

To test the hypothesis that the 3-hydroxy-3-methylglutaryl coenzyme-A reductase inhibitor pravastatin ameliorates endothelium mediated responses of dilated coronary segments: the PREFACE (pravastatin related effects following angioplasty on coronary endothelium) trial. A double blind, randomised, placebo controlled, multicentre study. Four hospitals in the Netherlands. 63 non-smoking, non-hypercholesterolaemic patients scheduled for elective balloon angioplasty (pravastatin 34, placebo 29). The effects of three months of pravastatin treatment (40 mg daily) on endothelium dependent vasomotor function were studied. Balloon angioplasty was undertaken one month after randomisation, and coronary vasomotor function tests using acetylcholine were performed two months after balloon angioplasty. The angiograms were analysed quantitatively. The efficacy measure was the acetylcholine induced change in mean arterial diameter, determined in the dilated segment and in an angiographically normal segment of an adjacent non-manipulated coronary artery. Increasing acetylcholine doses produced vasoconstriction in the dilated segments (p = 0.004) but not in the normal segments. Pravastatin did not affect the vascular response to acetylcholine in either the dilated segments (p = 0.09) or the non-dilated sites. Endothelium dependent vasomotion in normal segments was correlated with that in dilated segments (r = 0.47, p < 0.001). There were fewer procedure related events in the pravastatin group than in the placebo group (p < 0.05). Endothelium dependent vasomotion in normal segments is correlated with that in dilated segments. A significant beneficial effect of pravastatin on endothelial function could not be shown, but in the dilated segments there was a trend towards a beneficial treatment effect in the pravastatin group.

Sham transcranial electrical stimulation and its effects on corticospinal excitability: a systematic review and meta-analysis.

PubMed

Dissanayaka, Thusharika D; Zoghi, Maryam; Farrell, Michael; Egan, Gary F; Jaberzadeh, Shapour

2018-02-23

Sham stimulation is used in randomized controlled trials (RCTs) to assess the efficacy of active stimulation and placebo effects. It should mimic the characteristics of active stimulation to achieve blinding integrity. The present study was a systematic review and meta-analysis of the published literature to identify the effects of sham transcranial electrical stimulation (tES) - including anodal and cathodal transcranial direct current stimulation (a-tDCS, c-tDCS), transcranial alternating current stimulation (tACS), transcranial random noise stimulation (tRNS) and transcranial pulsed current stimulation (tPCS) - on corticospinal excitability (CSE), compared to baseline in healthy individuals. Electronic databases - PubMed, CINAHL, Scopus, Science Direct and MEDLINE (Ovid) - were searched for RCTs of tES from 1990 to March 2017. Thirty RCTs were identified. Using a random-effects model, meta-analysis of a-tDCS, c-tDCS, tACS, tRNS and tPCS studies showed statistically non-significant pre-post effects of sham interventions on CSE. This review found evidence for statically non-significant effects of sham tES on CSE.

MCMC Sampling for a Multilevel Model with Nonindependent Residuals within and between Cluster Units

ERIC Educational Resources Information Center

Browne, William; Goldstein, Harvey

2010-01-01

In this article, we discuss the effect of removing the independence assumptions between the residuals in two-level random effect models. We first consider removing the independence between the Level 2 residuals and instead assume that the vector of all residuals at the cluster level follows a general multivariate normal distribution. We…

The Effect of Altering the Context Clues in Prose on Reading Rate in a Search Task

ERIC Educational Resources Information Center

Coke, Esther U.

1977-01-01

To determine whether the connectedness of prose passages had any effect on the behavior of readers who searched for information in the passages, the behavior of readers who saw the normal arrangement of a passage was contrasted with the behavior of readers who saw the random arrangement of the passage. (HOD)

Effects of high protein diets on fat-free mass and muscle protein synthesis following weight loss: a randomized controlled trial

USDA-ARS?s Scientific Manuscript database

Context: The benefits of high protein diets for sparing lean body mass and sustaining skeletal muscle protein metabolism during short-term weight loss in normal-weight adults are not well described. Objective: Determine the effects of varying levels of dietary protein intake on body compos...

Aggregate and Individual Replication Probability within an Explicit Model of the Research Process

ERIC Educational Resources Information Center

Miller, Jeff; Schwarz, Wolf

2011-01-01

We study a model of the research process in which the true effect size, the replication jitter due to changes in experimental procedure, and the statistical error of effect size measurement are all normally distributed random variables. Within this model, we analyze the probability of successfully replicating an initial experimental result by…

The Performance of Methods to Test Upper-Level Mediation in the Presence of Nonnormal Data

ERIC Educational Resources Information Center

Pituch, Keenan A.; Stapleton, Laura M.

2008-01-01

A Monte Carlo study compared the statistical performance of standard and robust multilevel mediation analysis methods to test indirect effects for a cluster randomized experimental design under various departures from normality. The performance of these methods was examined for an upper-level mediation process, where the indirect effect is a fixed…

A two-way enriched clinical trial design: combining advantages of placebo lead-in and randomized withdrawal.

PubMed

Ivanova, Anastasia; Tamura, Roy N

2015-12-01

A new clinical trial design, designated the two-way enriched design (TED), is introduced, which augments the standard randomized placebo-controlled trial with second-stage enrichment designs in placebo non-responders and drug responders. The trial is run in two stages. In the first stage, patients are randomized between drug and placebo. In the second stage, placebo non-responders are re-randomized between drug and placebo and drug responders are re-randomized between drug and placebo. All first-stage data, and second-stage data from first-stage placebo non-responders and first-stage drug responders, are utilized in the efficacy analysis. The authors developed one, two and three degrees of freedom score tests for treatment effect in the TED and give formulae for asymptotic power and for sample size computations. The authors compute the optimal allocation ratio between drug and placebo in the first stage for the TED and compare the operating characteristics of the design to the standard parallel clinical trial, placebo lead-in and randomized withdrawal designs. Two motivating examples from different disease areas are presented to illustrate the possible design considerations. © The Author(s) 2011.

Chronic repeated exposure to weather-related stimuli elicits few symptoms of chronic stress in captive molting and non-molting European starlings (Sturnus vulgaris).

PubMed

de Bruijn, Robert; Reed, J Michael; Romero, L Michael

2017-10-01

Repeated exposure to acute stressors causes dramatic changes in an animal's stress physiology and the cumulative effects are often called chronic stress. Recently we showed that short-term exposure to weather-related stimuli, such as temperature change, artificial precipitation, and food restriction, cause acute responses in captive European starlings (Sturnus vulgaris). Here, we examined the effect of repeated exposure to weather-related stressors on heart rate and corticosterone (CORT) of captive non-molting and molting European starlings. Four times every day for 3 weeks, birds were exposed to either 30 min of a subtle (3°C) decrease in temperature, a short bout of simulated rain, or 2 hr of food removal. The order and time of presentation were randomly assigned on each day. We found no differences in heart rate or heart rate variability. Furthermore, there were no changes in baseline CORT levels, CORT negative feedback efficacy, or maximal adrenal capacity. Mass increased across the experimental period only in molting birds. CORT responses to restraint were decreased in both groups following treatment, suggesting the birds had downregulated their responses to acute stress. Molting birds showed evidence of suppression of the HPA axis compared with non-molting birds, which is consistent with previous research. Overall, our data show that repeated exposure to weather-related stressors does not elicit most of the symptoms normally associated with chronic stress. © 2018 Wiley Periodicals, Inc.

Effects of polymorphism rs3123554 in the cannabinoid receptor gene type 2 (CB2R) on metabolic and adiposity parameters after weight loss with two hypocaloric diets.

PubMed

de Luis, D A; Mulero, I; Primo, D; Izaola, O; Aller, R

2018-05-01

The role of CB2R gene variants on weight loss after a dietary intervention remained unclear. Our aim was to analyze the effects of rs3123554 of CB2R receptor gene on metabolic and adiposity parameters after two different hypocaloric diets in obese subjects. A Caucasian population of 280 obese patients was enrolled. Patients were randomly allocated during 3 months to one of two diets (Diet I - moderate in carbohydrate. Vs Diet II - normal in carbohydrate). In both genotype groups (GG vs GA + AA), body weight, body mass index (BMI), fat mass, waist circumference and systolic blood pressure decreased after diet I and II. The decrease of these parameters was higher in non A allele carriers than A allele carriers. Pre- and post-dietary intervention, body weight, BMI, fat mass and waist circumference were higher in A allele carriers than non A allele carriers. In non A allele carriers, the decrease of glucose, insulin, HOMA-IR and Interleukin-6 levels was higher than A allele carriers after both diets. Carriers of the minor allele of rs3123554 variant of CB2R gene loose less body weight during two different hypocaloric diets. The improvement of metabolic parameters was better in no A allele carriers than A allele carriers. Copyright © 2018 Elsevier B.V. All rights reserved.

Quenched bond randomness: Superfluidity in porous media and the strong violation of universality

NASA Astrophysics Data System (ADS)

Falicov, Alexis; Berker, A. Nihat

1997-04-01

The effects of quenched bond randomness are most readily studied with superfluidity immersed in a porous medium. A lattice model for3He-4He mixtures and incomplete4He fillings in aerogel yields the signature effect of bond randomness, namely the conversion of symmetry-breaking first-order phase transitions into second-order phase transitions, the λ-line reaching zero temperature, and the elimination of non-symmetry-breaking first-order phase transitions. The model recognizes the importance of the connected nature of aerogel randomness and thereby yields superfluidity at very low4He concentrations, a phase separation entirely within the superfluid phase, and the order-parameter contrast between mixtures and incomplete fillings, all in agreement with experiments. The special properties of the helium mixture/aerogel system are distinctly linked to the aerogel properties of connectivity, randomness, and tenuousness, via the additional study of a regularized “jungle-gym” aerogel. Renormalization-group calculations indicate that a strong violation of the empirical universality principle of critical phenomena occurs under quenched bond randomness. It is argued that helium/aerogel critical properties reflect this violation and further experiments are suggested. Renormalization-group analysis also shows that, adjoiningly to the strong universality violation (which hinges on the occurrence or non-occurrence of asymptotic strong coupling—strong randomness under rescaling), there is a new “hyperuniversality” at phase transitions with asymptotic strong coupling—strong randomness behavior, for example assigning the same critical exponents to random- bond tricriticality and random- field criticality.

Human mammary epithelial cells exhibit a bimodal correlated random walk pattern.

PubMed

Potdar, Alka A; Jeon, Junhwan; Weaver, Alissa M; Quaranta, Vito; Cummings, Peter T

2010-03-10

Organisms, at scales ranging from unicellular to mammals, have been known to exhibit foraging behavior described by random walks whose segments confirm to Lévy or exponential distributions. For the first time, we present evidence that single cells (mammary epithelial cells) that exist in multi-cellular organisms (humans) follow a bimodal correlated random walk (BCRW). Cellular tracks of MCF-10A pBabe, neuN and neuT random migration on 2-D plastic substrates, analyzed using bimodal analysis, were found to reveal the BCRW pattern. We find two types of exponentially distributed correlated flights (corresponding to what we refer to as the directional and re-orientation phases) each having its own correlation between move step-lengths within flights. The exponential distribution of flight lengths was confirmed using different analysis methods (logarithmic binning with normalization, survival frequency plots and maximum likelihood estimation). Because of the presence of non-uniform turn angle distribution of move step-lengths within a flight and two different types of flights, we propose that the epithelial random walk is a BCRW comprising of two alternating modes with varying degree of correlations, rather than a simple persistent random walk. A BCRW model rather than a simple persistent random walk correctly matches the super-diffusivity in the cell migration paths as indicated by simulations based on the BCRW model.

Effect of hydralazine on duration of soft tissue local anesthesia following dental treatment: a randomized clinical trial.

PubMed

Fakheran Esfahani, Omid; Pouraboutaleb, Mohammad Fazel; Khorami, Behnam

2015-01-01

Prolonged numbness following routine dental treatments can cause difficulties in speaking and swallowing and may result in inadvertent biting of soft tissues. Local injection of vasodilator agents may represent a solution to this problem. The aim of this study was to evaluate the effect of submucosal injection of hydralazine hydrochloride (HCl) on the duration of oral soft tissue anesthesia after routine dental treatment. This randomized, single-blinded, controlled clinical trial included 50 patients who received inferior alveolar nerve block (2% lidocaine with 1:100,000 epinephrine) for simple restorative treatment. Upon completion of the dental treatment, patients randomly received a hydralazine HCl or sham injection in the same site as the local anesthetic injection. The reversal time to normal sensation of soft tissues (lips, tongue, and perioral skin) was evaluated and reported every 5 minutes by the patients, who followed an assessment protocol that they were taught in advance of treatment. Median recovery times in the hydralazine group and the sham group were 81.4 (SD, 3.6) and 221.8 (SD, 6.3) minutes, respectively. Based on Kaplan-Meier survival analysis, the duration of soft tissue anesthesia in the 2 groups was significantly different (P < 0.0001). By 1 hour after the reversal injection, 76% of subjects receiving hydralazine HCl had returned to normal intraoral and perioral sensation, but none of the subjects in the sham group reported normal sensation. Based on these results, submucosal injection of hydralazine HCl can be considered a safe and effective method to reduce the duration of local anesthetic-induced soft tissue numbness and the related functional problems.

Pulsatile luteinizing hormone patterns in the follicular phase of the menstrual cycle, polycystic ovarian disease (PCOD) and non-PCOD secondary amenorrhea.

PubMed

Burger, C W; Korsen, T; van Kessel, H; van Dop, P A; Caron, F J; Schoemaker, J

1985-12-01

To characterize the oscillations of plasma LH in normally cycling and amenorrheic women, three groups of women were studied: I, normal women during the follicular phase of the cycle (n = 9); II, women with polycystic ovarian disease (PCOD; n = 11); and III, women with non-PCOD secondary amenorrhea (n = 12). Blood samples were obtained at 10-min intervals for 6 h on 2 separate days. A pulse was defined as an increase in LH at least 20% over the preceding lowest value (nadir). Since LHRH release immediately follows the nadir of the LH levels, the nadir interval (NI) was used for analysis. For analysis, the results from 1 day were selected at random from each subject, and from each day, the same number of NIs also were randomly selected. When two NIs from each patient were selected, the median NI was 75 min in group I, 45 min in group II, and 45 min in group III. When three or four NIs were chosen, the median NI was 60 min in group I, 50 min in group II, and 40 min in group III. The differences between the groups were statistically significant. When three NIs were selected, the mean of the corresponding LH amplitudes was 2.8 U/liter in group I, 6.0 U/liter in group II, and 1.5 U/liter in group III. The differences between these groups were statistically significant. Thus, the NI in PCOD patients was shorter than that during the follicular phase of the cycle, but this short NI is not unique for PCOD, since the NI in non-PCOD secondary amenorrhea patients was even smaller. The LH amplitude was higher in PCOD and lower in non-PCOD secondary amenorrhea compared to that during the follicular phase of the cycle. The decrease in NI in PCOD and/or non-PCOD secondary amenorrhea vs. the NI of the follicular phase could be explained by either a higher frequency of LHRH pulses from the hypothalamus or an increased sensitivity of the pituitary leading to a greater response of the pituitary to LHRH pulses.

Comparison of data mining techniques applied to fetal heart rate parameters for the early identification of IUGR fetuses.

PubMed

Magenes, G; Bellazzi, R; Malovini, A; Signorini, M G

2016-08-01

The onset of fetal pathologies can be screened during pregnancy by means of Fetal Heart Rate (FHR) monitoring and analysis. Noticeable advances in understanding FHR variations were obtained in the last twenty years, thanks to the introduction of quantitative indices extracted from the FHR signal. This study searches for discriminating Normal and Intra Uterine Growth Restricted (IUGR) fetuses by applying data mining techniques to FHR parameters, obtained from recordings in a population of 122 fetuses (61 healthy and 61 IUGRs), through standard CTG non-stress test. We computed N=12 indices (N=4 related to time domain FHR analysis, N=4 to frequency domain and N=4 to non-linear analysis) and normalized them with respect to the gestational week. We compared, through a 10-fold crossvalidation procedure, 15 data mining techniques in order to select the more reliable approach for identifying IUGR fetuses. The results of this comparison highlight that two techniques (Random Forest and Logistic Regression) show the best classification accuracy and that both outperform the best single parameter in terms of mean AUROC on the test sets.

Making electronic prescribing alerts more effective: scenario-based experimental study in junior doctors

PubMed Central

Shah, Priya; Wyatt, Jeremy C; Makubate, Boikanyo; Cross, Frank W

2011-01-01

Objective Expert authorities recommend clinical decision support systems to reduce prescribing error rates, yet large numbers of insignificant on-screen alerts presented in modal dialog boxes persistently interrupt clinicians, limiting the effectiveness of these systems. This study compared the impact of modal and non-modal electronic (e-) prescribing alerts on prescribing error rates, to help inform the design of clinical decision support systems. Design A randomized study of 24 junior doctors each performing 30 simulated prescribing tasks in random order with a prototype e-prescribing system. Using a within-participant design, doctors were randomized to be shown one of three types of e-prescribing alert (modal, non-modal, no alert) during each prescribing task. Measurements The main outcome measure was prescribing error rate. Structured interviews were performed to elicit participants' preferences for the prescribing alerts and their views on clinical decision support systems. Results Participants exposed to modal alerts were 11.6 times less likely to make a prescribing error than those not shown an alert (OR 11.56, 95% CI 6.00 to 22.26). Those shown a non-modal alert were 3.2 times less likely to make a prescribing error (OR 3.18, 95% CI 1.91 to 5.30) than those not shown an alert. The error rate with non-modal alerts was 3.6 times higher than with modal alerts (95% CI 1.88 to 7.04). Conclusions Both kinds of e-prescribing alerts significantly reduced prescribing error rates, but modal alerts were over three times more effective than non-modal alerts. This study provides new evidence about the relative effects of modal and non-modal alerts on prescribing outcomes. PMID:21836158

Estimating and testing interactions when explanatory variables are subject to non-classical measurement error.

PubMed

Murad, Havi; Kipnis, Victor; Freedman, Laurence S

2016-10-01

Assessing interactions in linear regression models when covariates have measurement error (ME) is complex.We previously described regression calibration (RC) methods that yield consistent estimators and standard errors for interaction coefficients of normally distributed covariates having classical ME. Here we extend normal based RC (NBRC) and linear RC (LRC) methods to a non-classical ME model, and describe more efficient versions that combine estimates from the main study and internal sub-study. We apply these methods to data from the Observing Protein and Energy Nutrition (OPEN) study. Using simulations we show that (i) for normally distributed covariates efficient NBRC and LRC were nearly unbiased and performed well with sub-study size ≥200; (ii) efficient NBRC had lower MSE than efficient LRC; (iii) the naïve test for a single interaction had type I error probability close to the nominal significance level, whereas efficient NBRC and LRC were slightly anti-conservative but more powerful; (iv) for markedly non-normal covariates, efficient LRC yielded less biased estimators with smaller variance than efficient NBRC. Our simulations suggest that it is preferable to use: (i) efficient NBRC for estimating and testing interaction effects of normally distributed covariates and (ii) efficient LRC for estimating and testing interactions for markedly non-normal covariates. © The Author(s) 2013.

High-Throughput Analysis of Age-Dependent Protein Changes in Layer II/III of the Human Orbitofrontal Cortex

NASA Astrophysics Data System (ADS)

Kapadia, Fenika

Studies on the orbitofrontal cortex (OFC) during normal aging have shown a decline in cognitive functions, a loss of spines/synapses in layer III and gene expression changes related to neural communication. Biological changes during the course of normal aging are summarized into 9 hallmarks based on aging in peripheral tissue. Whether these hallmarks apply to non-dividing brain tissue is not known. Therefore, we opted to perform large-scale proteomic profiling of the OFC layer II/III during normal aging from 15 young and 18 old male subjects. MaxQuant was utilized for label-free quantification and statistical analysis by the Random Intercept Model (RIM) identified 118 differentially expressed (DE) age-related proteins. Altered neural communication was the most represented hallmark of aging (54% of DE proteins), highlighting the importance of communication in the brain. Functional analysis showed enrichment in GABA/glutamate signaling and pro-inflammatory responses. The former may contribute to alterations in excitation/inhibition, leading to cognitive decline during aging.

When Human Walking is a Random Walk

NASA Astrophysics Data System (ADS)

Hausdorff, J. M.

1998-03-01

The complex, hierarchical locomotor system normally does a remarkable job of controlling an inherently unstable, multi-joint system. Nevertheless, the stride interval --- the duration of a gait cycle --- fluctuates from one stride to the next, even under stationary conditions. We used random walk analysis to study the dynamical properties of these fluctuations under normal conditions and how they change with disease and aging. Random walk analysis of the stride-to-stride fluctuations of healthy, young adult men surprisingly reveals a self-similar pattern: fluctuations at one time scale are statistically similar to those at multiple other time scales (Hausdorff et al, J Appl Phsyiol, 1995). To study the stability of this fractal property, we analyzed data obtained from healthy subjects who walked for 1 hour at their usual pace, as well as at slower and faster speeds. The stride interval fluctuations exhibited long-range correlations with power-law decay for up to a thousand strides at all three walking rates. In contrast, during metronomically-paced walking, these long-range correlations disappeared; variations in the stride interval were uncorrelated and non-fractal (Hausdorff et al, J Appl Phsyiol, 1996). To gain insight into the mechanism(s) responsible for this fractal property, we examined the effects of aging and neurological impairment. Using detrended fluctuation analysis (DFA), we computed α, a measure of the degree to which one stride interval is correlated with previous and subsequent intervals over different time scales. α was significantly lower in healthy elderly subjects compared to young adults (p < .003) and in subjects with Huntington's disease, a neuro-degenerative disorder of the central nervous system, compared to disease-free controls (p < 0.005) (Hausdorff et al, J Appl Phsyiol, 1997). α was also significantly related to degree of functional impairment in subjects with Huntington's disease (r=0.78). Recently, we have observed that just as there are changes with α during aging, there also changes with development. Apparently, the fractal scaling of walking does not become mature until children are eleven years old. Conclusions: The fractal dynamics of spontaneous stride interval fluctuations are normally quite robust and are apparently intrinsic to the healthy adult locomotor system. However, alterations in this fractal scaling property are associated with impairment in central nervous system control, aging and neural development.

Full Bayes Poisson gamma, Poisson lognormal, and zero inflated random effects models: Comparing the precision of crash frequency estimates.

PubMed

Aguero-Valverde, Jonathan

2013-01-01

In recent years, complex statistical modeling approaches have being proposed to handle the unobserved heterogeneity and the excess of zeros frequently found in crash data, including random effects and zero inflated models. This research compares random effects, zero inflated, and zero inflated random effects models using a full Bayes hierarchical approach. The models are compared not just in terms of goodness-of-fit measures but also in terms of precision of posterior crash frequency estimates since the precision of these estimates is vital for ranking of sites for engineering improvement. Fixed-over-time random effects models are also compared to independent-over-time random effects models. For the crash dataset being analyzed, it was found that once the random effects are included in the zero inflated models, the probability of being in the zero state is drastically reduced, and the zero inflated models degenerate to their non zero inflated counterparts. Also by fixing the random effects over time the fit of the models and the precision of the crash frequency estimates are significantly increased. It was found that the rankings of the fixed-over-time random effects models are very consistent among them. In addition, the results show that by fixing the random effects over time, the standard errors of the crash frequency estimates are significantly reduced for the majority of the segments on the top of the ranking. Copyright © 2012 Elsevier Ltd. All rights reserved.

Effects of short-term low- and high-carbohydrate diets on postprandial metabolism in non-diabetic and diabetic subjects.

PubMed

Culling, K S; Neil, H A W; Gilbert, M; Frayn, K N

2009-06-01

Low-fat high-carbohydrate diets raise plasma triacylglycerol (TG) concentrations. To test whether the nature of the carbohydrate affects metabolic responses, we conducted a randomized cross-over study using a short-term, intensive dietary modification. Eight non-diabetic subjects and four subjects with diet-controlled type 2 diabetes participated. They followed three isoenergetic diets, each for 3 days: high-fat (50% energy from fat), high-starch and high-sugar (each 70% energy from carbohydrate). Normal foods were provided. We measured plasma TG and glucose concentrations, fasting and after a standard test meal, on day 4 following each dietary period. Fasting TG concentrations were greatest following the high-sugar diet (mean+/-SEM for all subjects 1900+/-420micromol/l) and lowest following high-fat (1010+/-130micromol/l) (P=0.001); high-starch (mean 1500+/-310) and high-fat did not differ significantly (P=0.06). There was a greater effect in the diabetic subjects (diet x diabetes status interaction, P=0.008). Postprandial TG concentrations were similarly affected by prior diet (P<0.001) with each diet different from the others (P

DOE Office of Scientific and Technical Information (OSTI.GOV)

Eich, Hans Theodor; Gossmann, Axel; Engert, Andreas

Purpose: The role of radiotherapy (RT) after intensive chemotherapy in patients with advanced stage Hodgkin's lymphoma (HL) is still unclear. The German Hodgkin Study Group (GHSG) randomized HD12 trial was designed to test whether consolidative RT in the region of initial bulky disease and of residual disease is necessary after effective chemotherapy. A quality control program based on a multidisciplinary panel of radiation oncologists, radiologists, and medical oncologists who reviewed all patients' staging and restaging imaging was initiated. Methods and Materials: A total of 1661 patients aged 16 to 65 years with HL in Stage IIB (large mediastinal mass and/ormore » E-lesions) or Stage III to IV were randomized from January 1999 to January 2003 according to a factorial design between: 8 esc.BEACOPP + RT (arm A), 8 esc.BEACOPP non-RT (arm B), 4+4BEACOPP + RT (arm C), 4+4BEACOPP non-RT (arm D). Results: In the fifth interim analysis, 1449 patients were eligible for the arm comparison with regard to RT. After a median observation time of 48 months the FFTF rate was 86% and the OS 92%. The FFTF was 95% in the RT arms A+C and 88% in the non-RT arms B+D: no sequential significant difference. One thousand and eighty four patients were evaluated by the panel. The panel defined initial bulky disease in 800 patients and residual disease in 600 patients. The panel recommended continuation of therapy according to the randomization for 934 of 1084 patients and additive RT independently from the randomization arm for 145 of 1084 patients. Conclusions: The study showed that RT can be reduced substantially after effective chemotherapy. However, because of the irradiation of 10% of patients in the non-RT arms, equivalent effectiveness of a non-RT strategy cannot be proved. A substantial limitation of consolidative RT according to expert panel recommendations appears to be possible without reducing effectiveness.« less

Cerebrospinal Fluid Biomarkers and Reserve Variables as Predictors of Future "Non-Cognitive" Outcomes of Alzheimer's Disease.

PubMed

Ingber, Adam P; Hassenstab, Jason; Fagan, Anne M; Benzinger, Tammie L S; Grant, Elizabeth A; Holtzman, David M; Morris, John C; Roe, Catherine M

2016-01-01

The influence of reserve variables and Alzheimer's disease (AD) biomarkers on cognitive test performance has been fairly well-characterized. However, less is known about the influence of these factors on "non-cognitive" outcomes, including functional abilities and mood. We examined whether cognitive and brain reserve variables mediate how AD biomarker levels in cognitively normal persons predict future changes in function, mood, and neuropsychiatric behavior. Non-cognitive outcomes were examined in 328 individuals 50 years and older enrolled in ongoing studies of aging and dementia at the Knight Alzheimer Disease Research Center (ADRC). All participants were cognitively normal at baseline (Clinical Dementia Rating [CDR] 0), completed cerebrospinal fluid (CSF) and structural neuroimaging studies within one year of baseline, and were followed for an average of 4.6 annual visits. Linear mixed effects models explored how cognitive reserve and brain reserve variables mediate the relationships between AD biomarker levels and changes in function, mood, and neuropsychiatric behavior in cognitively normal participants. Education levels did not have a significant effect on predicting non-cognitive decline. However, participants with smaller brain volumes exhibited the worst outcomes on measures of mood, functional abilities, and behavioral disturbance. This effect was most pronounced in individuals who also had abnormal CSF biomarkers. The findings suggest that brain reserve plays a stronger, or earlier, role than cognitive reserve in protecting against non-cognitive impairment in AD.

Dimensional scaling for impact cratering and perforation

NASA Technical Reports Server (NTRS)

Watts, Alan; Atkinson, Dale; Rieco, Steve

1993-01-01

This report summarizes the development of two physics-based scaling laws for describing crater depths and diameters caused by normal incidence impacts into aluminum and TFE Teflon. The report then describes equations for perforations in aluminum and TFE Teflon for normal impacts. Lastly, this report also studies the effects of non-normal incidence on cratering and perforation.

Multiple Regression with Varying Levels of Correlation among Predictors: Monte Carlo Sampling from Normal and Non-Normal Populations.

ERIC Educational Resources Information Center

Vasu, Ellen Storey

1978-01-01

The effects of the violation of the assumption of normality in the conditional distributions of the dependent variable, coupled with the condition of multicollinearity upon the outcome of testing the hypothesis that the regression coefficient equals zero, are investigated via a Monte Carlo study. (Author/JKS)

[Parodontocid efficiency in complex treatment and prevention of gingivitis].

PubMed

Makeeva, I M; Turkina, A Iu; Poliakova, M A; Babina, K S

2013-01-01

Antiplaque/antigingivitis effect of an alcohol-free mouthrinse Parodontocid were evaluated by randomized parallel group clinical trial. Sixty patients with gingivitis were clinically examined to determine PHP, RMNPI and PMA indexes. After professional dental prophylaxis, subjects were randomly assigned in two groups to 10 days oral hygiene program. Group 1 patients used only toothbrush and prophylactic toothpaste while in group 2 persons used Parodontocid in conjunction with normal brushing and flossing.Parodontocid significantly reduced plaque and gingivitis compared to negative control.

Comparative effects of meditation and exercise on physical and psychosocial health outcomes: a review of randomized controlled trials.

PubMed

Edwards, Meghan K; Loprinzi, Paul D

2018-03-01

No review papers have examined studies that have directly compared non-active forms of meditation with exercise to evaluate effects on physical or psychosocial outcomes, which was the purpose of this paper. Studies were included if they had a randomized controlled trial (RCT) design, included a non-active form of meditation and exercise as intervention arms, and evaluated physical or psychosocial outcomes. The quality of included RCTs was rated using the Cochrane Collaboration's tool for assessing risk of bias in randomized trials. Five RCTs met the inclusion criteria. The total sample size across all studies was N = 325. Of the main outcomes assessed across the five studies, meditation was shown to be more effective than the exercise comparison arm when evaluating the psychosocial outcomes of anxiety, altruism, and life changes. Additionally, meditation was more effective at reducing chronic neck pain at rest and pain-related bothersomeness. Exercise, however, was more effective in improving physical health-related quality of life, HDL and LDL cholesterol, and fasting blood glucose levels. The interventions were found to be comparable when evaluating the outcomes of well-being, ethanol consumption, and perceived stress levels. Four of the evaluated studies were determined to have an overall 'unclear' risk of bias and one study was found to have a 'high' risk of bias. Exercise and non-active meditation may uniquely influence various health-related outcomes. A continued exploration of the effects of exercise and non-active meditation in controlled trials may yield a better understanding of their benefits.

Clinical breast examination screening by trained laywomen in Malawi integrated with other health services.

PubMed

Gutnik, Lily; Lee, Clara; Msosa, Vanessa; Moses, Agnes; Stanley, Christopher; Mzumara, Suzgo; Liomba, N George; Gopal, Satish

2016-07-01

Breast cancer awareness and early detection are limited in sub-Saharan Africa. Resource limitations make screening mammography or clinical breast examination (CBE) by physicians or nurses impractical in many settings. We aimed to assess feasibility and performance of CBE by laywomen in urban health clinics in Malawi. Four laywomen were trained to deliver breast cancer educational talks and conduct CBE. After training, screening was implemented in diverse urban health clinics. Eligible women were ≥30 y, with no prior breast cancer or breast surgery, and clinic attendance for reasons other than a breast concern. Women with abnormal CBE were referred to a study surgeon. All palpable masses confirmed by surgeon examination were pathologically sampled. Patients with abnormal screening CBE but normal surgeon examination underwent breast ultrasound confirmation. In addition, 50 randomly selected women with normal screening CBE underwent breast ultrasound, and 45 different women with normal CBE were randomly assigned to surgeon examination. Among 1220 eligible women, 1000 (82%) agreed to CBE. Lack of time (69%) was the commonest reason for refusal. Educational talk attendance was associated with higher CBE participation (83% versus 77%, P = 0.012). Among 1000 women screened, 7% had abnormal CBE. Of 45 women with normal CBE randomized to physician examination, 43 had normal examinations and two had axillary lymphadenopathy not detected by CBE. Sixty of 67 women (90%) with abnormal CBE attended the referral visit. Of these, 29 (48%) had concordant abnormal physician examination. Thirty-one women (52%) had discordant normal physician examination, all of whom also had normal breast ultrasounds. Compared with physician examination, sensitivity for CBE by laywomen was 94% (confidence interval [CI] 79%-99%), specificity 58% (CI, 46%-70%), positive predictive value 48% (CI, 35%-62%), and negative predictive value 96% (CI, 85%-100%). Of 13 women who underwent recommended pathologic sampling of a breast lesion, two had cytologic dysplasia and all others benign results. CBE uptake in Lilongwe clinics was high. CBE by laywomen compared favorably with physician examination and follow-up was good. Our intervention can serve as a model for wider implementation. Performance in rural areas, effects on cancer stage and mortality, and cost effectiveness require evaluation. Copyright © 2016 Elsevier Inc. All rights reserved.

Clinical breast exam screening by trained laywomen in Malawi integrated with other health services

PubMed Central

Gutnik, Lily; Lee, Clara; Msosa, Vanessa; Moses, Agnes; Stanley, Christopher; Mzumara, Suzgo; Liomba, N. George; Gopal, Satish

2016-01-01

Background Breast cancer awareness and early detection are limited in sub-Saharan Africa. Resource limitations make screening mammography or clinical breast exam (CBE) by physicians or nurses impractical in many settings. We aimed to assess feasibility and performance of CBE by laywomen in urban health clinics in Malawi. Methods Four laywomen were trained to deliver breast cancer educational talksand conduct CBE. After training, screening was implemented in diverse urbanhealth clinics. Eligible women were ≥30 years, with no prior breast cancer or breast surgery, and clinic attendance for reasons other than abreast concern. Wo men with abnormal CBE were referred to a study surgeon. All palpable masses confirmed by surgeon exam were pathologically sampled. Patients with abnormal screening CBE but normal surgeon exam underwentbreast ultrasound con firmation. Additionally, 50 randomly selected women with normal screening CBE underwent breast ultrasound, and 45 different women with normal CBE were randomly assigned to surgeon exam. Results Among 1,220 eligible women, 1,000 (82%) agreed to CBE. Lack of time (69%) was the commonest reason for refusal. Educational talk attendance was associated with higher CBE participation (83% vs 77%, p=0.012). Among 1,000 women screened, 7% had abnormal CBE. Of 45 women with normal CBE randomized to physician exam, 43 had normal exams and two had axillary lymphadenopathy not detected by CBE. Sixty of 67 women (90%) with abnormal CBE attended the referral visit. Of these, 29 (48%) had concordant abnormal physician exam. Thirty-one women (52%) had discordant normal physician exam, all of whom also had normal breast ultrasounds. Compared to physician exam, sensitivity for CBE by laywomen was 94% (CI 79-99%), specificity 58% (CI 46-70%), positive predictive value 48% (CI 35-62%), and negative predictive value 96% (CI 85-100%). Of 13 women who underwent recommended pathologic sampling of a breast lesion, two had cytologic dysplasia and all others benign results. Conclusions and relevance CBE uptake in Lilongwe clinics was high. CBE by laywomen compared favorably with physician exam, and follow-up was good. Our intervention can serve as a model for wider implementation. Performance in rural areas, effects on cancer stage and mortality, and cost-effectiveness require evaluation. PMID:27451869

A non-Hertzian method for solving wheel-rail normal contact problem taking into account the effect of yaw

NASA Astrophysics Data System (ADS)

Liu, Binbin; Bruni, Stefano; Vollebregt, Edwin

2016-09-01

A novel approach is proposed in this paper to deal with non-Hertzian normal contact in wheel-rail interface, extending the widely used Kik-Piotrowski method. The new approach is able to consider the effect of the yaw angle of the wheelset against the rail on the shape of the contact patch and on pressure distribution. Furthermore, the method considers the variation of profile curvature across the contact patch, enhancing the correspondence to CONTACT for highly non-Hertzian contact conditions. The simulation results show that the proposed method can provide more accurate estimation than the original algorithm compared to Kalker's CONTACT, and that the influence of yaw on the contact results is significant under certain circumstances.

Pelvic floor muscle training for bowel dysfunction following colorectal cancer surgery: A systematic review.

PubMed

Lin, Kuan-Yin; Granger, Catherine L; Denehy, Linda; Frawley, Helena C

2015-11-01

To identify, evaluate and synthesize the evidence examining the effectiveness of pelvic floor muscle training (PFMT) on bowel dysfunction in patients who have undergone colorectal cancer surgery. Eight electronic databases (MEDLINE 1950-2014; CINAHL 1982-2014; EMBASE 1980-2014; Scopus 1823-2014; PsycINFO 1806-2014; Web of Science 1970-2014; Cochrane Library 2014; PEDro 1999-2014) were systematically searched in March 2014. Reference lists of identified articles were cross referenced and hand searched. Randomized controlled trials, cohort studies and case series were included if they investigated the effects of conservative treatments, including PFMT on bowel function in patients with colorectal cancer following surgery. Two reviewers independently assessed the risk of bias of studies using the Newcastle-Ottawa Scale (NOS). Six prospective non-randomized studies and two retrospective studies were included. The mean (SD) NOS risk of bias score was 4.9 (1.2) out of 9; studies were limited by a lack of non-exposed cohort, lack of independent blinded assessment, heterogeneous treatment protocols, and lack of long-term follow-up. The majority of studies reported significant improvements in stool frequency, incontinence episodes, severity of fecal incontinence, and health-related quality of life (HRQoL) after PFMT. Meta-analysis was not possible due to lack of randomized controlled trials. Pelvic floor muscle training for patients following surgery for colorectal cancer appears to be associated with improvements in bowel function and HRQoL. Results from non-randomized studies are promising but randomized controlled trials with sufficient power are needed to confirm the effectiveness of PFMT in this population. © 2014 Wiley Periodicals, Inc.

Improving the dictionary lookup approach for disease normalization using enhanced dictionary and query expansion.

PubMed

Jonnagaddala, Jitendra; Jue, Toni Rose; Chang, Nai-Wen; Dai, Hong-Jie

2016-01-01

The rapidly increasing biomedical literature calls for the need of an automatic approach in the recognition and normalization of disease mentions in order to increase the precision and effectivity of disease based information retrieval. A variety of methods have been proposed to deal with the problem of disease named entity recognition and normalization. Among all the proposed methods, conditional random fields (CRFs) and dictionary lookup method are widely used for named entity recognition and normalization respectively. We herein developed a CRF-based model to allow automated recognition of disease mentions, and studied the effect of various techniques in improving the normalization results based on the dictionary lookup approach. The dataset from the BioCreative V CDR track was used to report the performance of the developed normalization methods and compare with other existing dictionary lookup based normalization methods. The best configuration achieved an F-measure of 0.77 for the disease normalization, which outperformed the best dictionary lookup based baseline method studied in this work by an F-measure of 0.13.Database URL: https://github.com/TCRNBioinformatics/DiseaseExtract. © The Author(s) 2016. Published by Oxford University Press.

Specific Safety Profile of Bevacizumab in Asian Patients With Advanced NSCLC

PubMed Central

Chen, Zhenguang; Zhong, Beilong; Lun, Xueping; Lai, Yingrong; Bella, Amos Ela; Yang, Weilin; Wu, Jiabin

2015-01-01

Abstract Randomized studies have obtained varying findings regarding the benefits and toxicities of bevacizumab in the treatment of nonsmall cell lung cancer (NSCLC). It is unclear whether the discrepancies among trials are due to ethnic/racial differences. We therefore performed a meta-analysis of all published, randomized, controlled clinical trials involving bevacizumab in patients with NSCLC to assess its effectiveness and safety in Asian and non-Asian populations. Results from the phase II JO19907 trial, the phase III AVAiL and ECOG 4599 trials, and the phase IV SAiL trials were used to calculate the benefits and toxicities of bevacizumab in Asian and non-Asian patients. Combined statistical estimates, including hazard ratios and odds ratios, were calculated using fixed-effects and random-effects models. A total of 4308 patients were evaluated. Combining bevacizumab with different chemotherapy regimens resulted in similar objective response rates, overall survival, and progression-free survival in Asian and non-Asian populations. Disease control rates, however, were only reported in Asian populations. The rates of severe bleeding (relative risk [RR], 2.17; P = 0.02) and thromboembolism (RR, 3.65; P < 0.0001) were significantly higher, while the rate of severe proteinuria was significantly lower (RR, 0.43; P < 0.0001), in non-Asian than in Asian populations. The rates of severe hypertension (P = 0.71) and hemoptysis (P = 0.66) were similar in Asian and non-Asian populations. Bevacizumab combined with chemotherapy for first-line NSCLC treatment showed similar benefits in Asian and non-Asian populations, but had specific safety profiles in each. PMID:26091469

Effects of Functional Fascial Taping on pain and function in patients with non-specific low back pain: a pilot randomized controlled trial.

PubMed

Chen, Shu-Mei; Alexander, Ron; Lo, Sing Kai; Cook, Jill

2012-10-01

To compare the short-term and medium-term effect of Functional Fascial Taping to placebo taping on pain and function in people with non-specific low back pain. A pilot randomized controlled trial with a 2-week intervention, and 2-, 6- and 12-week follow-up. Individuals with non-specific low back pain recruited from local communities. Forty-three participants with non-specific low back pain for more than 6 weeks were randomized into either Functional Fascial Taping group (n = 21) or placebo group (n = 22). The intervention group was treated with Functional Fascial Taping while the control group was treated with placebo taping. Both groups received four treatments over 2 weeks. Worst and average pain and function were assessed at baseline, after the 2-week intervention, and at 6 and 12 weeks follow-up. The Functional Fascial Taping group demonstrated significantly greater reduction in worst pain compared to placebo group after the 2-week intervention (P = 0.02, effect size = 0.74; 95% confidence interval 0.11-1.34). A higher proportion of participants in Functional Fascial Taping group attained the minimal clinically important difference in worst pain (P = 0.007) and function (P = 0.007) than those in placebo group after the 2-week intervention. There were no significant differences in either group's disability rating or clinically important difference in average pain at any time. Functional Fascial Taping reduced worst pain in patients with non-acute non-specific low back pain during the treatment phase. No medium-term differences in pain or function were observed.

Empirical constrained Bayes predictors accounting for non-detects among repeated measures.

PubMed

Moore, Reneé H; Lyles, Robert H; Manatunga, Amita K

2010-11-10

When the prediction of subject-specific random effects is of interest, constrained Bayes predictors (CB) have been shown to reduce the shrinkage of the widely accepted Bayes predictor while still maintaining desirable properties, such as optimizing mean-square error subsequent to matching the first two moments of the random effects of interest. However, occupational exposure and other epidemiologic (e.g. HIV) studies often present a further challenge because data may fall below the measuring instrument's limit of detection. Although methodology exists in the literature to compute Bayes estimates in the presence of non-detects (Bayes(ND)), CB methodology has not been proposed in this setting. By combining methodologies for computing CBs and Bayes(ND), we introduce two novel CBs that accommodate an arbitrary number of observable and non-detectable measurements per subject. Based on application to real data sets (e.g. occupational exposure, HIV RNA) and simulation studies, these CB predictors are markedly superior to the Bayes predictor and to alternative predictors computed using ad hoc methods in terms of meeting the goal of matching the first two moments of the true random effects distribution. Copyright © 2010 John Wiley & Sons, Ltd.

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

PubMed

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.

Adjunctive Aripiprazole Versus Placebo for Antipsychotic-Induced Hyperprolactinemia: Meta-Analysis of Randomized Controlled Trials

PubMed Central

Li, Xianbin; Tang, Yilang; Wang, Chuanyue

2013-01-01

Objective To compare the safety and efficacy of adjunctive aripiprazole versus placebo for antipsychotic-induced hyperprolactinemia. Methods Population: adult patients presenting with antipsychotic-induced hyperprolactinemia diagnosed by prolactin level with or without prolactin-related symptoms. Interventions: adjunctive aripiprazole vs. adjunctive placebo. Outcome measures: adverse events and efficacy of treatment. Studies: randomized controlled trials. Results Five randomized controlled trials with a total of 639 patients (326 adjunctive aripiprazole, 313 adjunctive placebo) met the inclusion criteria. Adjunctive aripiprazole was associated with a 79.11% (125/158) prolactin level normalization rate. Meta-analysis of insomnia, headache, sedation, psychiatric disorder, extrapyramidal symptom, dry mouth, and fatigue showed no significant differences in the adjunctive aripiprazole treatment group compared with the placebo group (risk difference (Mantel-Haenszel, random or fixed) −0.05 to 0.04 (95% confidence interval −0.13 to 0.16); I2 = 0% to 68%, P = 0.20 to 0.70). However, sedation, insomnia, and headache were more frequent when the adjunctive aripiprazole dose was higher than 15 mg/day. Meta-analysis of the prolactin level normalization indicated adjunctive aripiprazole was superior to placebo (risk difference (Mantel-Haenszel, random) 0.76 (95% confidence interval 0.67 to 0.85); I2 = 43%, P<0.00001). The subgroup analysis confirmed that the subjects who received adjunctive aripiprazole 5 mg/day showed a degree of prolactin normalization similar to that of all participants. No significant differences between groups in discontinuation and improvements of psychiatric symptoms. Conclusion Adjunctive aripiprazole is both safe and effective as a reasonable choice treatment for patients with antipsychotic-induced hyperprolactinemia. The appropriate dose of adjunctive aripiprazole may be 5 mg/day. PMID:23936389

Efficacy of zinc sulfate supplement on febrile seizure recurrence prevention in children with normal serum zinc level: A randomised clinical trial.

PubMed

Fallah, Razieh; Sabbaghzadegan, Saeideh; Karbasi, Sedighah Akhavan; Binesh, Fariba

2015-01-01

Serum zinc level might be related to pathogenesis of febrile seizure (FS). The purpose of this study was to evaluate efficacy and safety of oral zinc supplementation on FS recurrence prevention in non-zinc-deficient children. In a randomized clinical study, one hundred 18 to 60 mo old children with normal zinc level with first simple FS were referred to Shahid Sadoughi Hospital, Yazd, Iran from May 2012 to June 2013, were randomly assigned to two groups to receive 2 mg/kg/d zinc sulfate for six consecutive months or placebo as control group and were followed up for 1 y for FS recurrence. 41 girls and 59 boys with mean age of 2.47 ± 1.01 y were evaluated. Race, mean weight, height and body fat were similar in both groups. FS recurrence occurred in 19 children (38%) in the control group [95% confidence interval (CI): 19.45%-53.95%] and in 11 children (22%) in the zinc sulfate (95% CI: 57.47%-89.13%) groups, respectively; and the zinc group had lower FS recurrence (P = 0.03). The mean serum zinc level before intervention was lower in children with FS recurrence (72.43 ± 14.58 μg/dL versus 96.33 ± 12.69 μg/dL, P = 0.04). Gastrointestinal side effects (vomiting in five children, heartburn in two children and abdominal pain in one child) were seen in 16% of the zinc group and vomiting occurred in two children (4%) in control group and frequency of adverse events was similar in the two groups (P = 0.1). Zinc supplementation should be considered as effective and safe in prevention of FS recurrence. Copyright © 2015 Elsevier Inc. All rights reserved.

Robotically assisted treadmill exercise training for improving peak fitness in chronic motor incomplete spinal cord injury: A randomized controlled trial

PubMed Central

Scott, William; York, Henry; Theyagaraj, Melita; Price-Miller, Naomi; McQuaid, Jean; Eyvazzadeh, Megan; Ivey, Frederick M.; Macko, Richard F.

2016-01-01

Objective To assess the effectiveness of robotically assisted body weight supported treadmill training (RABWSTT) for improving cardiovascular fitness in chronic motor incomplete spinal cord injury (CMISCI). Design Pilot prospective randomized, controlled clinical trial. Setting Outpatient rehabilitation specialty hospital. Participants Eighteen individuals with CMISCI with American Spinal Injury Association (ASIA) level between C4 and L2 and at least one-year post injury. Interventions CMISCI participants were randomized to RABWSTT or a home stretching program (HSP) three times per week for three months. Those in the home stretching group were crossed over to three months of RABWSTT following completion of the initial three month phase. Outcome measures Peak oxygen consumption (peak VO2) was measured during both robotic treadmill walking and arm cycle ergometry: twice at baseline, once at six weeks (mid-training) and twice at three months (post-training). Peak VO2 values were normalized for body mass. Results The RABWSTT group improved peak VO2 by 12.3% during robotic treadmill walking (20.2 ± 7.4 to 22.7 ± 7.5 ml/kg/min, P = 0.018), compared to a non-significant 3.9% within group change observed in HSP controls (P = 0.37). Neither group displayed a significant change in peak VO2 during arm cycle ergometry (RABWSTT, 8.5% (P = 0.25); HSP, 1.76% (P = 0.72)). A repeated measures analysis showed statistically significant differences between treatments for peak VO2 during both robotic treadmill walking (P = 0.002) and arm cycle ergometry (P = 0.001). Conclusion RABWSTT is an effective intervention model for improving peak fitness levels assessed during robotic treadmill walking in persons with CMISCI. PMID:25520035

Stopping the effective non-fluoroquinolone antibiotics at day 7 vs continuing until day 14 in adults with acute pyelonephritis requiring hospitalization: A randomized non-inferiority trial.

PubMed

Rudrabhatla, Pavankumar; Deepanjali, Surendran; Mandal, Jharna; Swaminathan, Rathinam Palamalai; Kadhiravan, Tamilarasu

2018-01-01

To evaluate whether stopping the effective antibiotic treatment following clinical improvement at Day 7 (Truncated treatment) would be non-inferior to continued treatment until Day 14 (Continued treatment) in patients with acute pyelonephritis (APN) requiring hospitalization treated with non-fluoroquinolone (non-FQ) antibiotics. Hospitalized adult men and non-pregnant women with culture-confirmed APN were eligible for participation after they had clinically improved following empirical or culture-guided treatment with intravenous non-FQ antibiotic(s). We excluded patients with severe sepsis, abscesses, prostatitis, recurrent or catheter-associated urinary tract infection, or urinary tract obstruction. We randomized eligible patients on Day 7 of effective treatment and assessed them at Weeks 1 and 6 after treatment completion. The primary outcome was retreatment for recurrent urinary tract infection. The prespecified non-inferiority margin was 15%. Between March 17, 2015 and August 22, 2016, we randomly allocated 54 patients-27 patients in each arm. Twenty-four (44%) patients were male, and 26 (48%) had diabetes mellitus. Escherichia coli was the most common urinary isolate (47 [87%] patients); 36 (78%) were resistant to ciprofloxacin. In all, 41 (76%) patients received amikacin-based treatment. At the end of 6 weeks, no patient in the truncated treatment arm required retreatment, whereas 1 patient in the continued treatment arm was retreated. Difference (90% CI) in retreatment was -3.7% (-15.01% to 6.15%). Upper bound of the difference (6.15%) was below the prespecified limit, establishing non-inferiority of truncated treatment. Asymptomatic bacteriuria at Week 6 was similar between the two arms (3/24 vs. 3/26; P = 1.0). Patients in the truncated treatment arm had significantly shorter hospital stay (8 [7-10] vs. 14 [14-15] days; P < 0.001) and less antibiotic consumption per patient (8.4 ± 2.8 vs. 17.4 ± 8.3 DDDs; P < 0.001). Stopping the effective non-FQ antibiotics following clinical improvement at Day 7 is non-inferior to continued treatment until Day 14 in selected patients with APN requiring hospitalization. Clinical Trials Registry-India; CTRI/2016/04/006810.

Effects of supplemental vitamin D and calcium on oxidative DNA damage marker in normal colorectal mucosa: a randomized clinical trial.

PubMed

Fedirko, Veronika; Bostick, Roberd M; Long, Qi; Flanders, W Dana; McCullough, Marjorie L; Sidelnikov, Eduard; Daniel, Carrie R; Rutherford, Robin E; Shaukat, Aasma

2010-01-01

The exact antineoplastic effects of calcium and vitamin D(3) in the human colon are unclear. Animal and in vitro studies show that these two agents reduce oxidative stress; however, these findings have never been investigated in humans. To address this, we conducted a pilot, randomized, double-blind, placebo-controlled, 2 x 2 factorial clinical trial to test the effects of calcium and vitamin D(3) on a marker of oxidative DNA damage, 8-hydroxy-2'-deoxyguanosine (8-OH-dG), in the normal colorectal mucosa. Patients (N = 92) with at least one pathology-confirmed colorectal adenoma were treated with 2 g/d calcium and/or 800 IU/d vitamin D(3) versus placebo over 6 months. Overall labeling and colorectal crypt distribution of 8-OH-dG in biopsies of normal-appearing rectal mucosa were detected by standardized automated immunohistochemistry and quantified by image analysis. After 6 months of treatment, 8-OH-dG labeling along the full lengths of colorectal crypts decreased by 22% (P = 0.15) and 25% (P = 0.10) in the calcium and vitamin D(3) groups, respectively, but not in the calcium plus vitamin D(3) group. The estimated treatment effects were strongest among participants with higher baseline colon crypt vitamin D receptor expression (P = 0.05). Overall, these preliminary results indicate that calcium and vitamin D(3) may decrease oxidative DNA damage in the normal human colorectal mucosa, support the hypothesis that 8-OH-dG labeling in colorectal crypts is a treatable oxidative DNA damage biomarker of risk for colorectal neoplasms, and provide support for further investigation of calcium and vitamin D(3) as chemopreventive agents against colorectal neoplasms.

Photodynamic Therapy for Actinic Keratoses: A Randomized Prospective Non-sponsored Cost-effectiveness Study of Daylight-mediated Treatment Compared with Light-emitting Diode Treatment.

PubMed

Neittaanmäki-Perttu, Noora; Grönroos, Mari; Karppinen, Toni; Snellman, Erna; Rissanen, Pekka

2016-02-01

Daylight-mediated photodynamic therapy (DL-PDT) is considered as effective as conventional PDT using artificial light (light-emitting diode (LED)-PDT) for treatment of actinic keratoses (AK). This randomized prospective non-sponsored study assessed the cost-effectiveness of DL-PDT compared with LED-PDT. Seventy patients with 210 AKs were randomized to DL-PDT or LED-PDT groups. Effectiveness was assessed at 6 months. The costs included societal costs and private costs, including the time patients spent in treatment. Results are presented as incremental cost-effectiveness ratio (ICER). The total costs per patient were significantly lower for DL-PDT (€132) compared with LED-PDT (€170), giving a cost saving of €38 (p = 0.022). The estimated probabilities for patients' complete response were 0.429 for DL-PDT and 0.686 for LED-PDT; a difference in probability of being healed of 0.257. ICER showed a monetary gain of €147 per unit of effectiveness lost. DL-PDT is less costly and less effective than LED-PDT. In terms of cost-effectiveness analysis, DL-PDT provides lower value for money compared with LED-PDT.

Gaussian statistics of the cosmic microwave background: Correlation of temperature extrema in the COBE DMR two-year sky maps

NASA Technical Reports Server (NTRS)

Kogut, A.; Banday, A. J.; Bennett, C. L.; Hinshaw, G.; Lubin, P. M.; Smoot, G. F.

1995-01-01

We use the two-point correlation function of the extrema points (peaks and valleys) in the Cosmic Background Explorer (COBE) Differential Microwave Radiometers (DMR) 2 year sky maps as a test for non-Gaussian temperature distribution in the cosmic microwave background anisotropy. A maximum-likelihood analysis compares the DMR data to n = 1 toy models whose random-phase spherical harmonic components a(sub lm) are drawn from either Gaussian, chi-square, or log-normal parent populations. The likelihood of the 53 GHz (A+B)/2 data is greatest for the exact Gaussian model. There is less than 10% chance that the non-Gaussian models tested describe the DMR data, limited primarily by type II errors in the statistical inference. The extrema correlation function is a stronger test for this class of non-Gaussian models than topological statistics such as the genus.

Effect of non-normality on test statistics for one-way independent groups designs.

PubMed

Cribbie, Robert A; Fiksenbaum, Lisa; Keselman, H J; Wilcox, Rand R

2012-02-01

The data obtained from one-way independent groups designs is typically non-normal in form and rarely equally variable across treatment populations (i.e., population variances are heterogeneous). Consequently, the classical test statistic that is used to assess statistical significance (i.e., the analysis of variance F test) typically provides invalid results (e.g., too many Type I errors, reduced power). For this reason, there has been considerable interest in finding a test statistic that is appropriate under conditions of non-normality and variance heterogeneity. Previously recommended procedures for analysing such data include the James test, the Welch test applied either to the usual least squares estimators of central tendency and variability, or the Welch test with robust estimators (i.e., trimmed means and Winsorized variances). A new statistic proposed by Krishnamoorthy, Lu, and Mathew, intended to deal with heterogeneous variances, though not non-normality, uses a parametric bootstrap procedure. In their investigation of the parametric bootstrap test, the authors examined its operating characteristics under limited conditions and did not compare it to the Welch test based on robust estimators. Thus, we investigated how the parametric bootstrap procedure and a modified parametric bootstrap procedure based on trimmed means perform relative to previously recommended procedures when data are non-normal and heterogeneous. The results indicated that the tests based on trimmed means offer the best Type I error control and power when variances are unequal and at least some of the distribution shapes are non-normal. © 2011 The British Psychological Society.

Stationary Random Metrics on Hierarchical Graphs Via {(min,+)}-type Recursive Distributional Equations

NASA Astrophysics Data System (ADS)

Khristoforov, Mikhail; Kleptsyn, Victor; Triestino, Michele

2016-07-01

This paper is inspired by the problem of understanding in a mathematical sense the Liouville quantum gravity on surfaces. Here we show how to define a stationary random metric on self-similar spaces which are the limit of nice finite graphs: these are the so-called hierarchical graphs. They possess a well-defined level structure and any level is built using a simple recursion. Stopping the construction at any finite level, we have a discrete random metric space when we set the edges to have random length (using a multiplicative cascade with fixed law {m}). We introduce a tool, the cut-off process, by means of which one finds that renormalizing the sequence of metrics by an exponential factor, they converge in law to a non-trivial metric on the limit space. Such limit law is stationary, in the sense that glueing together a certain number of copies of the random limit space, according to the combinatorics of the brick graph, the obtained random metric has the same law when rescaled by a random factor of law {m} . In other words, the stationary random metric is the solution of a distributional equation. When the measure m has continuous positive density on {mathbf{R}+}, the stationary law is unique up to rescaling and any other distribution tends to a rescaled stationary law under the iterations of the hierarchical transformation. We also investigate topological and geometric properties of the random space when m is log-normal, detecting a phase transition influenced by the branching random walk associated to the multiplicative cascade.

Metformin effects on ovarian ultrasound appearance and steroidogenic function in normal-weight normoinsulinemic women with polycystic ovary syndrome: a randomized double-blind placebo-controlled clinical trial.

PubMed

Romualdi, Daniela; Giuliani, Maddalena; Cristello, Francesca; Fulghesu, Anna Maria; Selvaggi, Luigi; Lanzone, Antonio; Guido, Maurizio

2010-05-01

To investigate metformin effects on the endocrine-metabolic parameters and ovarian morphology in normoinsulinemic women with polycystic ovary syndrome (PCOS). Randomized double-blind study. Operative Division of Endocrinological Gynecology, Università Cattolica del Sacro Cuore. Twenty-eight normal-weight normoinsulinemic PCOS women. Patients were randomized to receive metformin 500 mg twice a day (group A, 15 subjects) or placebo (group B, 13 subjects) for 6 months. Ultrasonographic pelvic exams, hormonal and lipid features, and oral glucose tolerance test were performed at baseline and after 3 and 6 months of treatment. Hormonal and glycoinsulinemic assessment, ovarian ultrasound appearance. Glycoinsulinemic assessment remained unvaried in both groups. About 70% of patients in group A experienced a restoration of menstrual cyclicity. Metformin significantly decreased testosterone levels at 3 and 6 months) and 17-hydroxyprogesterone levels at 6 months, and improved hirsutism score at 6 months. No clinical or hormonal modifications occurred in group B. Metformin, but not placebo, reduced ovarian volume and stromal/total area ratio at 3 and 6 months. Metformin seems to improve the menstrual pattern and ultrasonographic ovarian features in normoinsulinemic PCOS women. These effects seem to be, at least in part, independent of the insulin-lowering properties of the drug. Copyright 2010 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Student Sorting and Bias in Value Added Estimation: Selection on Observables and Unobservables. NBER Working Paper No. 14666

ERIC Educational Resources Information Center

Rothstein, Jesse

2009-01-01

Non-random assignment of students to teachers can bias value added estimates of teachers' causal effects. Rothstein (2008a, b) shows that typical value added models indicate large counter-factual effects of 5th grade teachers on students' 4th grade learning, indicating that classroom assignments are far from random. This paper quantifies the…

VLED and formula LED in the management of type 2 diabetes: defining the clinical need and research requirements.

PubMed

Lean, M

2011-02-01

It has been known for many years that substantial weight loss, achieved by bariatric surgery or non-surgical means can mean normalize glucose tolerance. Recent randomized controlled trial evidence indicates that >15 kg weight loss is necessary, to this and it may lead to near normalization (doubling) of life expectancy. Less than 5% of patients achieve this through even the best, evidence-based medical weight management programme (Counterweight http://www.counterweight.org). A weight loss of >15 kg is easily achievable by 8 weeks very low-energy diet (VLED)/LELD (Low energy Liquid-formula Diet) in compliant patients, with little difference between 400 and 800 kcal day(-1) , but weight maintenance after VLED has until recently been so poor that VLED is not, at present, recommended in clinical guidelines. However, mean weight loss close to >15 kg can be maintained 18-24 months using a variety of maintenance strategies. These include a structured reintroduction of foods linked to an education programme with behavioural strategies, intermittent VLED use and prescribable anti-obesity drugs (dexfenfluramine, orlistat, sibutramine). Most of these studies have been in non-diabetic subjects. A new 'curative' paradigm in type 2 diabetes mellitus management, aiming to normalize glucose tolerance and health risks by achieving and maintaining >15 kg loss, as soon as possible after diagnosis, should be highly acceptable to patients, generating many additional Quality Adjusted Life Years (QALYs). It is likely to be highly cost-effective by avoiding the current recommended, mainly palliative, model, using polypharmacy which provides an overall risk reduction of only 5-10%. Clinical trials are on-going to establish the feasibility of delivering formula (LELD) and a maintenance programme to large numbers of patients within routine primary care. There is urgent need, to run similar studies in diabetic patients. New approaches to long-term (lifelong) maintenance of weight loss and a non-diabetic state may include anti-obesity drugs. © 2011 The Author. Clinical Obesity © 2011 International Association for the Study of Obesity.

Trained Inquiry Skills on Heat and Temperature Concepts

NASA Astrophysics Data System (ADS)

Hasanah, U.; Hamidah, I.; Utari, S.

2017-09-01

Inquiry skills are skills that aperson needs in developing concepts, but the results of the study suggest that these skills haven’t yet been trained along with the development of concepts in science feeding, found the difficulties of students in building the concept scientifically. Therefore, this study aims to find ways that are effective in training inquiry skills trough Levels of Inquiry (LoI) learning. Experimental research with one group pretest-postest design, using non-random sampling samples in one of vocational high school in Cimahi obtained purposively 33 students of X class. The research using the inquiry skills test instrument in the form of 15questions multiple choice with reliability in very high category. The result of data processing by using the normalized gain value obtained an illustration that the ways developed in the LoI are considered effective trained inquiry skills in the middle category. Some of the ways LoI learning are considered effective in communicating aspects through discovery learning, predicting trough interactive demonstration, hypotheses through inquiry lesson, and interpreting data through inquiry lab, but the implementation of LoI learning in this study hasn’t found a way that is seen as effective for trespassing aspects of designing an experiment.

Variable size computer-aided detection prompts and mammography film reader decisions

PubMed Central

Gilbert, Fiona J; Astley, Susan M; Boggis, Caroline RM; McGee, Magnus A; Griffiths, Pamela M; Duffy, Stephen W; Agbaje, Olorunsola F; Gillan, Maureen GC; Wilson, Mary; Jain, Anil K; Barr, Nicola; Beetles, Ursula M; Griffiths, Miriam A; Johnson, Jill; Roberts, Rita M; Deans, Heather E; Duncan, Karen A; Iyengar, Geeta

2008-01-01

Introduction The purpose of the present study was to investigate the effect of computer-aided detection (CAD) prompts on reader behaviour in a large sample of breast screening mammograms by analysing the relationship of the presence and size of prompts to the recall decision. Methods Local research ethics committee approval was obtained; informed consent was not required. Mammograms were obtained from women attending routine mammography at two breast screening centres in 1996. Films, previously double read, were re-read by a different reader using CAD. The study material included 315 cancer cases comprising all screen-detected cancer cases, all subsequent interval cancers and 861 normal cases randomly selected from 10,267 cases. Ground truth data were used to assess the efficacy of CAD prompting. Associations between prompt attributes and tumour features or reader recall decisions were assessed by chi-squared tests. Results There was a highly significant relationship between prompting and a decision to recall for cancer cases and for a random sample of normal cases (P < 0.001). Sixty-four per cent of all cases contained at least one CAD prompt. In cancer cases, larger prompts were more likely to be recalled (P = 0.02) for masses but there was no such association for calcifications (P = 0.9). In a random sample of 861 normal cases, larger prompts were more likely to be recalled (P = 0.02) for both mass and calcification prompts. Significant associations were observed with prompting and breast density (p = 0.009) for cancer cases but not for normal cases (P = 0.05). Conclusions For both normal cases and cancer cases, prompted mammograms were more likely to be recalled and the prompt size was also associated with a recall decision. PMID:18724867

Variable size computer-aided detection prompts and mammography film reader decisions.

PubMed

Gilbert, Fiona J; Astley, Susan M; Boggis, Caroline Rm; McGee, Magnus A; Griffiths, Pamela M; Duffy, Stephen W; Agbaje, Olorunsola F; Gillan, Maureen Gc; Wilson, Mary; Jain, Anil K; Barr, Nicola; Beetles, Ursula M; Griffiths, Miriam A; Johnson, Jill; Roberts, Rita M; Deans, Heather E; Duncan, Karen A; Iyengar, Geeta

2008-01-01

The purpose of the present study was to investigate the effect of computer-aided detection (CAD) prompts on reader behaviour in a large sample of breast screening mammograms by analysing the relationship of the presence and size of prompts to the recall decision. Local research ethics committee approval was obtained; informed consent was not required. Mammograms were obtained from women attending routine mammography at two breast screening centres in 1996. Films, previously double read, were re-read by a different reader using CAD. The study material included 315 cancer cases comprising all screen-detected cancer cases, all subsequent interval cancers and 861 normal cases randomly selected from 10,267 cases. Ground truth data were used to assess the efficacy of CAD prompting. Associations between prompt attributes and tumour features or reader recall decisions were assessed by chi-squared tests. There was a highly significant relationship between prompting and a decision to recall for cancer cases and for a random sample of normal cases (P < 0.001). Sixty-four per cent of all cases contained at least one CAD prompt. In cancer cases, larger prompts were more likely to be recalled (P = 0.02) for masses but there was no such association for calcifications (P = 0.9). In a random sample of 861 normal cases, larger prompts were more likely to be recalled (P = 0.02) for both mass and calcification prompts. Significant associations were observed with prompting and breast density (p = 0.009) for cancer cases but not for normal cases (P = 0.05). For both normal cases and cancer cases, prompted mammograms were more likely to be recalled and the prompt size was also associated with a recall decision.

Effect of influenza vaccination on oxidative stress products in breath.

PubMed

Phillips, Michael; Cataneo, Renee N; Chaturvedi, Anirudh; Danaher, Patrick J; Devadiga, Anantrai; Legendre, David A; Nail, Kim L; Schmitt, Peter; Wai, James

2010-06-01

Viral infections cause increased oxidative stress, so a breath test for oxidative stress biomarkers (alkanes and alkane derivatives) might provide a new tool for early diagnosis. We studied 33 normal healthy human subjects receiving scheduled treatment with live attenuated influenza vaccine (LAIV). Each subject was his or her own control, since they were studied on day 0 prior to vaccination, and then on days 2, 7 and 14 following vaccination. Breath volatile organic compounds (VOCs) were collected with a breath collection apparatus, then analyzed by automated thermal desorption with gas chromatography and mass spectroscopy. A Monte Carlo simulation technique identified non-random VOC biomarkers of infection based on their C-statistic values (area under curve of receiver operating characteristic). Treatment with LAIV was followed by non-random changes in the abundance of breath VOCs. 2, 8-Dimethyl-undecane and other alkane derivatives were observed on all days. Conservative multivariate models identified vaccinated subjects on day 2 (C-statistic = 0.82, sensitivity = 63.6% and specificity = 88.5%); day 7 (C-statistic = 0.94, sensitivity = 88.5% and specificity = 92.3%); and day 14 (C-statistic = 0.95, sensitivity = 92.3% and specificity = 92.3%). The altered breath VOCs were not detected in live attenuated influenza vaccine, excluding artifactual contamination. LAIV vaccination in healthy humans elicited a prompt and sustained increase in breath biomarkers of oxidative stress. A breath test for these VOCs could potentially identify humans who are acutely infected with influenza, but who have not yet developed clinical symptoms or signs of disease.

Comparison of efficacy of low-carbohydrate and low-fat diet education programs in non-alcoholic fatty liver disease: A randomized controlled study.

PubMed

Jang, Eun Chul; Jun, Dae Won; Lee, Seung Min; Cho, Yong Kyun; Ahn, Sang Bong

2018-02-01

Composition of macronutrients is important in non-alcoholic fatty liver disease (NAFLD). Diet education programs that mainly emphasize reducing fat consumption have been used for NAFLD patients. We compared the efficacy of conventional low-fat diet education with low-carbohydrate diet education in Korean NAFLD patients. One hundred and six NAFLD patients were randomly allocated to low-fat diet education or low-carbohydrate education groups for 8 weeks. Liver chemistry, liver / spleen ratio, and visceral fat using abdominal tomography were measured. Intrahepatic fat accumulation decreased significantly in the low-carbohydrate group compared to low-fat group (liver/spleen 0.85 vs. 0.92, P < 0.05). Normalization of ALT activity at week 8 was 38.5% for the low-carbohydrate and 16.7% for the low-fat group (P = 0.016). Not only liver enzyme, but also low density lipoprotein cholesterol and blood pressure levels significantly decreased in the low-carbohydrate group. Total energy intake was also further decreased in the low-carbohydrate group compared to the low-fat group. Although body weight changes were not different between the two groups, the carbohydrate group had a lower total abdominal fat amount. A low-carbohydrate diet program is more realistic and effective in reducing total energy intake and hepatic fat content in Korean NAFLD patients. This trial is registered with the National Research Institute of Health: KCT0000970 (https://cris.nih.go.kr/cris/index.jsp). © 2017 The Japan Society of Hepatology.

Methodological study of affine transformations of gene expression data with proposed robust non-parametric multi-dimensional normalization method.

PubMed

Bengtsson, Henrik; Hössjer, Ola

2006-03-01

Low-level processing and normalization of microarray data are most important steps in microarray analysis, which have profound impact on downstream analysis. Multiple methods have been suggested to date, but it is not clear which is the best. It is therefore important to further study the different normalization methods in detail and the nature of microarray data in general. A methodological study of affine models for gene expression data is carried out. Focus is on two-channel comparative studies, but the findings generalize also to single- and multi-channel data. The discussion applies to spotted as well as in-situ synthesized microarray data. Existing normalization methods such as curve-fit ("lowess") normalization, parallel and perpendicular translation normalization, and quantile normalization, but also dye-swap normalization are revisited in the light of the affine model and their strengths and weaknesses are investigated in this context. As a direct result from this study, we propose a robust non-parametric multi-dimensional affine normalization method, which can be applied to any number of microarrays with any number of channels either individually or all at once. A high-quality cDNA microarray data set with spike-in controls is used to demonstrate the power of the affine model and the proposed normalization method. We find that an affine model can explain non-linear intensity-dependent systematic effects in observed log-ratios. Affine normalization removes such artifacts for non-differentially expressed genes and assures that symmetry between negative and positive log-ratios is obtained, which is fundamental when identifying differentially expressed genes. In addition, affine normalization makes the empirical distributions in different channels more equal, which is the purpose of quantile normalization, and may also explain why dye-swap normalization works or fails. All methods are made available in the aroma package, which is a platform-independent package for R.

Cost-effectiveness of early interventions for non-specific low back pain: a randomized controlled study investigating medical yoga, exercise therapy and self-care advice.

PubMed

Aboagye, Emmanuel; Karlsson, Malin Lohela; Hagberg, Jan; Jensen, Irene

2015-02-01

To evaluate the cost-effectiveness of medical yoga as an early intervention compared with evidence-based exercise therapy and self-care advice for non-specific low back pain. Randomized controlled trial with a cost-effectiveness analysis. A total of 159 participants randomized into the medical yoga group (n = 52), the exercise therapy group (n = 52) and the self-care advice group (n = 55). The health outcome measure EQ-5D was applied to measure quality of life data combined with cost data collected from treatment groups from baseline to 12 months follow-up. Outcome measure was health-related quality of life (HRQL). Incremental cost per quality adjusted life year (QALY) was also calculated. Cost-effectiveness analysis was conducted primarily from the societal and employer perspectives. Medical yoga is cost-effective compared with self-care advice if an employer considers the significant improvement in the HRQL of an employee with low back pain justifies the additional cost of treatment (i.e. in this study EUR 150). From a societal perspective, medical yoga is a cost-effective treatment compared with exercise therapy and self-care advice if an additional QALY is worth EUR 11,500. Sensitivity analysis suggests that medical yoga is more cost-effective than its alternatives. Six weeks of uninterrupted medical yoga thera-py is a cost-effective early intervention for non-specific low back pain, when treatment recommendations are adhered to.

OBESITY AND PELVIC FLOOR DISORDERS: A REVIEW OF THE LITERATURE

PubMed Central

Greer, W. Jerod; Richter, Holly E.; Bartolucci, Alfred A.; Burgio, Kathryn L.

2011-01-01

OBJECTIVE To review the current literature and summarize the effect of obesity on outcomes of surgical treatment of pelvic floor disorders (PFDs) as well as the effect of weight loss on PFD symptoms. DATA SOURCES Relevant sources were identified by a MEDLINE search from 1966 to 2007 (key words: obesity, pelvic floor disorders, urinary incontinence, fecal incontinence, pelvic organ prolapse). References of relevant studies were hand searched. METHODS OF STUDY SELECTION Relevant human observational studies, randomized trials, and review articles were included. 246 articles were identified; 20 were used in reporting and analyzing the data. Meta-analyses were performed for topics meeting the appropriate criteria. TABULATION, INTEGRATION AND RESULTS There is good evidence that surgery for stress urinary incontinence in obese women is as safe as in their non-obese counterparts, but cure rates may be lower in the obese patient. Meta-analysis revealed cure rates of 81% and 85% for the obese and non-obese groups, respectively [P < 0.001; OR: 0.576 (95% CI: 0.426 – 0.779)] Combined bladder perforation rates were 1.2% in the obese and 6.6% in the non-obese [P = 0.015; OR: 0.277 (95% CI: 0.098 – 0.782)]. There is little evidence on which to base clinical decisions regarding the treatment of fecal incontinence (FI) and pelvic organ prolapse (POP) in obese women, as few comparative studies were identified addressing the outcomes of prolapse surgery in obese patients compared to normal-weight controls. Weight loss studies indicate that both bariatric and non-surgical weight loss lead to significant improvements in PFD symptoms. CONCLUSION Surgery for UI in obese women is safe, but more trials are needed to evaluate its long-term effectiveness as well as treatments for both FI and POP. Weight loss, both surgical and non-surgical, should be considered in the treatment of PFDs in the obese woman. PMID:18669733

Non-invasive high-frequency ventilation versus bi-phasic continuous positive airway pressure (BP-CPAP) following CPAP failure in infants <1250 g: a pilot randomized controlled trial.

PubMed

Mukerji, A; Sarmiento, K; Lee, B; Hassall, K; Shah, V

2017-01-01

Non-invasive high-frequency ventilation (NIHFV), a relatively new modality, is gaining popularity despite limited data. We sought to evaluate the effectiveness of NIHFV versus bi-phasic continuous positive airway pressure (BP-CPAP) in preterm infants failing CPAP. Infants with BW<1250 g on CPAP were randomly assigned to NIHFV or BP-CPAP if they met pre-determined criteria for CPAP failure. Infants were eligible for randomization after 72 h age and until 2000 g. Guidelines for adjustment of settings and criteria for failure of assigned mode were implemented. The primary aim was to assess feasibility of a larger trial. In addition, failure of assigned non-invasive respiratory support (NRS) mode, invasive mechanical ventilation (MV) 72 h and 7 days post-randomization, and bronchopulmonary dysplasia (BPD) were assessed. Thirty-nine infants were randomized to NIHFV (N=16) or BP-CPAP (N=23). There were no significant differences in mean (s.d.) postmenstrual age (28.6 (1.5) versus 29.0 (2.3) weeks, P=0.47), mean (s.d.) weight at randomization (965.0 (227.0) versus 958.1 (310.4) g, P=0.94) or other baseline demographics between the groups. Failure of assigned NRS mode was lower with NIHFV (37.5 versus 65.2%, P=0.09), although not statistically significant. There were no differences in rates of invasive MV 72 h and 7 days post-randomization or BPD. NIHFV was not superior to BP-CPAP in this pilot study. Effectiveness of NIHFV needs to be proven in larger multi-center, appropriately powered trials before widespread implementation.

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

NASA Astrophysics Data System (ADS)

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.

Normal Stresses, Contraction, and Stiffening in Sheared Elastic Networks

NASA Astrophysics Data System (ADS)

Baumgarten, Karsten; Tighe, Brian P.

2018-04-01

When elastic solids are sheared, a nonlinear effect named after Poynting gives rise to normal stresses or changes in volume. We provide a novel relation between the Poynting effect and the microscopic Grüneisen parameter, which quantifies how stretching shifts vibrational modes. By applying this relation to random spring networks, a minimal model for, e.g., biopolymer gels and solid foams, we find that networks contract or develop tension because they vibrate faster when stretched. The amplitude of the Poynting effect is sensitive to the network's linear elastic moduli, which can be tuned via its preparation protocol and connectivity. Finally, we show that the Poynting effect can be used to predict the finite strain scale where the material stiffens under shear.

Cellphone based mobile colposcope for the evaluation of women with abnormal cervical cancer screening

NASA Astrophysics Data System (ADS)

Kahn, Bruce S.; Kass, Alex J.; Waalen, Jill; Levitz, David

2015-03-01

Objective: Compare an inexpensive cell-phone based Mobile Colposcope, with a standard colposcope in the evaluation of women with abnormal Pap smear screening. Methodology: The study was a prospective, parallel noninferiority trial. Thirty women underwent colposcopy for the evaluation of an abnormal Pap smear. After application of acetic acid, images of the cervix were obtained with both a standard colposcope and the Mobile Colposcope. An additional set of images using both devices were obtained using the red-free (green filter) mode. Eight experienced gynecologists then evaluated 100 paired images (plain and green filter) from two different sites in random order using a web based assessment program. After reviewing each set of paired images, the expert would make an assessment of: 1) normal (no biopsy/ random biopsy), or 2) abnormal. For abnormal images, the expert then electronically marked the site(s) on the image where a biopsy was recommended. In image analysis, the cervical image was divided into 12 radial sectors and the marked sites for biopsy on the matched pairs were compared. Matched pairs that were considered normal, or those where biopsy site recommendations were within +/- 30° were considered equivalent; unmatched biopsy sites were considered non-equivalent. Results were compared using Wilcoxon Matched Pairs Signed Ranks Test. Expert assessment of Mobile Colposcope images compared with assessment by standard colposcope is currently onging. Conclusions: if the Mobile Colposcope demonstrates non-inferiority to imaging obtained with a standard colposcope and due to its low cost, it has the potential help improve cervical cancer screening in low resource settings.

Non-random loss of chromosome 3 during transition of Helicobacter pylori-associated gastric MALT to B-cell MALT lymphoma revealed by fluorescence in situ hybridization.

PubMed

Banerjee, S K; Weston, A P; Persons, D L; Campbell, D R

1997-12-16

Acquired gastric mucosa-associated lymphoid tissue (MALT) accumulates as a result of long-standing Helicobacter pylori (H. pylori) infection and from this acquired MALT, low-grade B-cell MALT lymphoma may develop. Carcinogenesis is a multistep, multifactorial process involving the progressive accumulation of genetic changes. To determine whether numerical chromosomal alterations are involved in the transition of H. pylori-associated human gastric MALT to low-grade B-cell MALT lymphoma, frozen biopsy specimens prospectively obtained from H. pylori positive gastric MALT and gastric MALT lymphoma patients, as well as normal control patients (normal gastroscopy/gastric mucosal histology/H. pylori negative), were analyzed by fluorescence in situ hybridization (FISH). Fluorescent, directly labeled alpha-satellite DNA probes, specific for the centromeres of chromosomes 1, 3, 4, 11, 17 and Y were used in this study. The non-random loss of chromosome 3 was detected in two MALT patients and in all five MALT lymphoma patients. Trisomy 17 was detected in one MALT patient and one MALT lymphoma patient. Trisomy 1 was detected in a single MALT lymphoma patient as was trisomy 3. None of the MALT patients had trisomy 3 or trisomy 1. Monosomy 17 was noted in one MALT lymphoma patient. Clonal aneusomy was not observed in any patient for chromosomes Y, 4 or 11. These results suggest that the consistent loss of chromosome 3 may be an important genetic alteration in the transformation of H. pylori-associated gastric MALT into low-grade B-cell gastric MALT lymphoma.

Exploring the reproducibility of functional connectivity alterations in Parkinson’s disease

PubMed Central

Onu, Mihaela; Wu, Tao; Roceanu, Adina; Bajenaru, Ovidiu

2017-01-01

Since anatomic MRI is presently not able to directly discern neuronal loss in Parkinson’s Disease (PD), studying the associated functional connectivity (FC) changes seems a promising approach toward developing non-invasive and non-radioactive neuroimaging markers for this disease. While several groups have reported such FC changes in PD, there are also significant discrepancies between studies. Investigating the reproducibility of PD-related FC changes on independent datasets is therefore of crucial importance. We acquired resting-state fMRI scans for 43 subjects (27 patients and 16 normal controls, with 2 replicate scans per subject) and compared the observed FC changes with those obtained in two independent datasets, one made available by the PPMI consortium (91 patients, 18 controls) and a second one by the group of Tao Wu (20 patients, 20 controls). Unfortunately, PD-related functional connectivity changes turned out to be non-reproducible across datasets. This could be due to disease heterogeneity, but also to technical differences. To distinguish between the two, we devised a method to directly check for disease heterogeneity using random splits of a single dataset. Since we still observe non-reproducibility in a large fraction of random splits of the same dataset, we conclude that functional heterogeneity may be a dominating factor behind the lack of reproducibility of FC alterations in different rs-fMRI studies of PD. While global PD-related functional connectivity changes were non-reproducible across datasets, we identified a few individual brain region pairs with marginally consistent FC changes across all three datasets. However, training classifiers on each one of the three datasets to discriminate PD scans from controls produced only low accuracies on the remaining two test datasets. Moreover, classifiers trained and tested on random splits of the same dataset (which are technically homogeneous) also had low test accuracies, directly substantiating disease heterogeneity. PMID:29182621

Efficacy and safety of 10-mg azilsartan compared with 8-mg candesartan cilexetil in Japanese patients with hypertension: a randomized crossover non-inferiority trial.

PubMed

Takahara, Mitsuyoshi; Shiraiwa, Toshihiko; Shindo, Megumi; Arai, Akie; Kusuda, Yuko; Katakami, Naoto; Kaneto, Hideaki; Matsuoka, Taka-Aki; Shimomura, Iichiro

2014-09-01

We investigated whether 10 mg per day of azilsartan, one-half of the normal dosage, would be non-inferior to 8 mg per day of candesartan cilexetil for controlling blood pressure in Japanese patients with hypertension. In this open-label, randomized, crossover trial, 309 hypertensive Japanese adults treated with 8-mg candesartan cilexetil were randomized into two arms and received either 10-mg azilsartan or 8-mg candesartan cilexetil in a crossover manner. The primary efficacy outcome was systolic blood pressure, and the margin of non-inferiority was set to be 2.5 mm Hg. The participants were 67±11 years old, and 180 (58%) were male. The baseline systolic and diastolic blood pressure levels were 127.1±13.2 and 69.7±11.2 mm Hg, respectively. During the study period, the difference in systolic blood pressure between the treatments with 10-mg azilsartan and 8-mg candesartan cilexetil was -1.7 mm Hg, with the two-sided 95% confidence interval (CI) ranged from -3.2 to -0.2 mm Hg. The upper boundary of the 95% CI was below the margin of 2.5 mm Hg, confirming the non-inferiority of 10-mg azilsartan to 8-mg candesartan cilexetil. The difference also reached significance (P=0.037). The corresponding difference in diastolic blood pressure was -1.4 (95% CI: -2.4 to -0.4) mm Hg (P=0.006). Treatment with 10-mg azilsartan was similar to 8-mg candesartan cilexetil in its association with rare adverse events. In conclusion, 10-mg azilsartan was non-inferior to 8-mg candesartan cilexetil for controlling systolic blood pressure in Japanese hypertensive patients already being treated with 8-mg candesartan cilexetil.

The origin and reduction of spurious extrahepatic counts observed in 90Y non-TOF PET imaging post radioembolization

NASA Astrophysics Data System (ADS)

Walrand, Stephan; Hesse, Michel; Jamar, François; Lhommel, Renaud

2018-04-01

Our literature survey revealed a physical effect unknown to the nuclear medicine community, i.e. internal bremsstrahlung emission, and also the existence of long energy resolution tails in crystal scintillation. None of these effects has ever been modelled in PET Monte Carlo (MC) simulations. This study investigates whether these two effects could be at the origin of two unexplained observations in 90Y imaging by PET: the increasing tails in the radial profile of true coincidences, and the presence of spurious extrahepatic counts post radioembolization in non-TOF PET and their absence in TOF PET. These spurious extrahepatic counts hamper the microsphere delivery check in liver radioembolization. An acquisition of a 32P vial was performed on a GSO PET system. This is the ideal setup to study the impact of bremsstrahlung x-rays on the true coincidence rate when no positron emission and no crystal radioactivity are present. A MC simulation of the acquisition was performed using Gate-Geant4. MC simulations of non-TOF PET and TOF-PET imaging of a synthetic 90Y human liver radioembolization phantom were also performed. Internal bremsstrahlung and long energy resolution tails inclusion in MC simulations quantitatively predict the increasing tails in the radial profile. In addition, internal bremsstrahlung explains the discrepancy previously observed in bremsstrahlung SPECT between the measure of the 90Y bremsstrahlung spectrum and its simulation with Gate-Geant4. However the spurious extrahepatic counts in non-TOF PET mainly result from the failure of conventional random correction methods in such low count rate studies and poor robustness versus emission-transmission inconsistency. A novel proposed random correction method succeeds in cleaning the spurious extrahepatic counts in non-TOF PET. Two physical effects not considered up to now in nuclear medicine were identified to be at the origin of the unusual 90Y true coincidences radial profile. TOF reconstruction removing of the spurious extrahepatic counts was theoretically explained by a better robustness against emission-transmission inconsistency. A novel random correction method was proposed to overcome the issue in non-TOF PET. Further studies are needed to assess the novel random correction method robustness.

Finding the right match: Mindfulness training may potentiate the therapeutic effect of non-judgment of inner experience on smoking cessation

PubMed Central

Schuman-Olivier, Zev D.; Hoeppner, Bettina B.; Evins, A. Eden; Brewer, Judson

2014-01-01

Mindfulness Training (MT) is an emerging therapeutic modality for addictive disorders. Non-judgment of inner experience, a component of mindfulness, may influence addiction treatment response. To test whether this component influences smoking cessation, tobacco smokers (n=85) in a randomized control trial of MT vs. Freedom from Smoking (FFS), a standard cognitive-behaviorally-oriented treatment, were divided into split-half subgroups based on baseline Five Facet Mindfulness Questionnaire non-judgment subscale. Smokers who rarely judge inner experience (non-judgment > 30.5) smoked less during follow-up when randomized to MT (3.9 cigs/d) vs. FFS (11.1 cigs/d), p <0.01. Measuring trait non-judgment may help personalize treatment assignments, improving outcomes. PMID:24611853

Two Autistic Savant Readers.

ERIC Educational Resources Information Center

O'Connor, N.; Hermelin, B.

1994-01-01

Two young autistic children exhibited normal reading comprehension but reading speeds considerably faster than controls. The effect of randomizing word order was minimal for the older of the two autistic boys. Results indicate that efficient grapheme-phoneme conversion is primarily responsible for the fast reading of the autistic children.…

THE EFFECTS ON LEARNING FROM A MOTION PICTURE FILM OF SELECTIVE CHANGES IN SOUND TRACK LOUDNESS LEVEL. FINAL REPORT.

ERIC Educational Resources Information Center

MOAKLEY, FRANCIS X.

EFFECTS OF PERIODIC VARIATIONS IN AN INSTRUCTIONAL FILM'S NORMAL LOUDNESS LEVEL FOR RELEVANT AND IRRELEVANT FILM SEQUENCES WERE MEASURED BY A MULTIPLE CHOICE TEST. RIGOROUS PILOT STUDIES, RANDOM GROUPING OF SEVENTH GRADERS FOR TREATMENTS, AND RATINGS OF RELEVANT AND IRRELEVANT PORTIONS OF THE FILM BY AN UNSPECIFIED NUMBER OF JUDGES PRECEDED THE…

Polarization and coherence in the Hanbury Brown–Twiss effect

NASA Astrophysics Data System (ADS)

Liu, Xianlong; Wu, Gaofeng; Pang, Xiaoyan; Kuebel, David; Visser, Taco D.

2018-07-01

We study the correlation of intensity fluctuations in random electromagnetic beams, the so-called Hanbury Brown-Twiss effect (HBT). We show that not just the state of coherence of the source, but also its state of polarization has a strong influence on the far-zone correlations. Different types of sources are found to have different upper bounds for the normalized HBT coefficient.

Which is your choice for prolonging the analgesic duration of single-shot interscalene brachial blocks for arthroscopic shoulder surgery? intravenous dexamethasone 5 mg vs. perineural dexamethasone 5 mg randomized, controlled, clinical trial.

PubMed

Chun, Eun Hee; Kim, Youn Jin; Woo, Jae Hee

2016-06-01

The aim of this study was to compare the effect of intravenous (I.V.) dexamethasone with that of perineural dexamethasone on the prolongation of analgesic duration of single-shot interscalene brachial plexus blocks (SISB) in patients undergoing arthroscopic shoulder surgery. We performed a prospective, randomized, double-blind, placebo-controlled study. Patients undergoing elective arthroscopic shoulder surgery with ultrasound-guided SISB were enrolled and randomized into 2 groups. A total volume of 12 mL of the study drug was prepared with a final concentration of 0.5% ropivacaine. In the I.V. group, patients received SISB using ropivacaine 5 mg mL with normal saline (control) with dexamethasone 5 mg I.V. injection. In the perineural group, patients received SISB using ropivacaine 5 mg mL with dexamethasone 5 mg, with normal saline 1 mL I.V. injection. The primary outcome was the time to the first analgesic request, defined as the time between the end of the operation and the first request of analgesics by the patient. The secondary outcomes included patient satisfaction scores, side effects, and neurological symptoms. Patients were randomly assigned to 1 of the 2 groups using a computer-generated randomization table. An anesthesiologist blinded to the group assignments prepared the solutions for injection. The patients and the investigator participating in the study were also blinded to the group assignments. One hundred patients were randomized. Data were analyzed for 99 patients. One case in the I.V. group was converted to open surgery and was therefore not included in the study. Perineural dexamethasone significantly prolonged analgesic duration (median, standard error: 1080 minutes, 117.5 minutes) compared with I.V. dexamethasone (810 minutes, 48.1 minutes) (P = 0.02). There were no significant differences in side effects, neurological symptoms, or changes in blood glucose values between the 2 groups. Our results show that perineural dexamethasone 5 mg is more effective than I.V. dexamethasone 5 mg with regard to analgesic duration of SISB for arthroscopic shoulder surgery.

Immediate therapist self-disclosure bolsters the effect of brief integrative psychotherapy on psychiatric symptoms and the perceptions of therapists: A randomized clinical trial.

PubMed

Ziv-Beiman, Sharon; Keinan, Giora; Livneh, Elad; Malone, Patrick S; Shahar, Golan

2017-09-01

We report a first randomized clinical trial examining the effect of immediate and non-immediate therapist self-disclosure in the context of a brief integrative psychotherapy for mild to moderate distress. A total of 86 patients with mild to moderate forms of distress were randomly divided into three 12-session integrative psychotherapy conditions based primarily on [Hill, C. E. (2009). Helping skills: Facilitating, exploration, insight, and action (3rd ed.). Washington, DC: American Psychological Association.] three-stage model. Therapists trained in this treatment modality were instructed to use either immediate self-disclosure (expressing feelings towards the patient/treatment/therapeutic relationship) or non-immediate self-disclosure (expressing personal or factual information regarding the therapist's life outside the treatment). In the comparison condition, the therapists were instructed to refrain from self-disclosure altogether. Immediate therapist self-disclosure reduced psychiatric symptoms among patients with elevated pretreatment symptoms (as assessed by the Brief Symptoms Inventory) and bolstered a favorable perception of the therapist. Therapists in both the immediate and non-immediate self-disclosure group evaluated themselves more favorably than their counterparts in the non-disclosure group. Therapist self-disclosure, particularly of the immediate type, might enhance the effect of brief integrative treatment on psychiatric symptoms of high symptomatic patients and contribute to favorable perception of therapists.

Student Participation under Random and Delayed Credit Contingencies

ERIC Educational Resources Information Center

Aspiranti, K. B.; McCleary, D. F.; McCleary, L. N.; Ga-lyon, C. E.; Blondin, C. A.; Yaw, J. S.; Williams, R. L.

2013-01-01

The authors examined the effects of randomized and delayed credit on the percentage of college students participating at four pre-defined levels on each class discussion day: non-participation, credit-level participation, frequent participation, and dominant participation. Although the same amount of participation credit was available to students…

Effect of betel chewing on the frequency of sister chromatid exchanges in pregnant women and women using oral contraceptives.

PubMed

Ghosh, P K; Ghosh, R

1988-06-01

The incidence of sister chromatid exchange (SCE) was investigated in the lymphocyte chromosomes of betel chewing and non-chewing normal women, pregnant women, and women using oral contraceptives. The frequency of SCE was found to be 7.82 +/- 0.24 and 8.27 +/- 0.27 in non-chewing pregnant women and women using oral contraceptives respectively, which were significantly higher than the mean value of 5.21 +/- 0.18 observed in non-chewing normal women. Betel chewing induced higher SCE in pregnant women and women using oral contraceptives, the frequencies being 11.79 +/- 0.38 and 12.51 +/- 0.44, respectively, which were significantly higher than the SCE frequency of 6.28 +/- 0.21 found in normal betel chewing females.

Urn models for response-adaptive randomized designs: a simulation study based on a non-adaptive randomized trial.

PubMed

Ghiglietti, Andrea; Scarale, Maria Giovanna; Miceli, Rosalba; Ieva, Francesca; Mariani, Luigi; Gavazzi, Cecilia; Paganoni, Anna Maria; Edefonti, Valeria

2018-03-22

Recently, response-adaptive designs have been proposed in randomized clinical trials to achieve ethical and/or cost advantages by using sequential accrual information collected during the trial to dynamically update the probabilities of treatment assignments. In this context, urn models-where the probability to assign patients to treatments is interpreted as the proportion of balls of different colors available in a virtual urn-have been used as response-adaptive randomization rules. We propose the use of Randomly Reinforced Urn (RRU) models in a simulation study based on a published randomized clinical trial on the efficacy of home enteral nutrition in cancer patients after major gastrointestinal surgery. We compare results with the RRU design with those previously published with the non-adaptive approach. We also provide a code written with the R software to implement the RRU design in practice. In detail, we simulate 10,000 trials based on the RRU model in three set-ups of different total sample sizes. We report information on the number of patients allocated to the inferior treatment and on the empirical power of the t-test for the treatment coefficient in the ANOVA model. We carry out a sensitivity analysis to assess the effect of different urn compositions. For each sample size, in approximately 75% of the simulation runs, the number of patients allocated to the inferior treatment by the RRU design is lower, as compared to the non-adaptive design. The empirical power of the t-test for the treatment effect is similar in the two designs.

The Hard but Necessary Task of Gathering Order-One Effect Size Indices in Meta-Analysis

ERIC Educational Resources Information Center

Ortego, Carmen; Botella, Juan

2010-01-01

Meta-analysis of studies with two groups and two measurement occasions must employ order-one effect size indices to represent study outcomes. Especially with non-random assignment, non-equivalent control group designs, a statistical analysis restricted to post-treatment scores can lead to severely biased conclusions. The 109 primary studies…

Effect of Polya Problem-Solving Model on Senior Secondary School Students' Performance in Current Electricity

ERIC Educational Resources Information Center

Olaniyan, Ademola Olatide; Omosewo, Esther O.; Nwankwo, Levi I.

2015-01-01

This study was designed to investigate the Effect of Polya Problem-Solving Model on Senior School Students' Performance in Current Electricity. It was a quasi experimental study of non- randomized, non equivalent pre-test post-test control group design. Three research questions were answered and corresponding three research hypotheses were tested…

Pravastatin and endothelium dependent vasomotion after coronary angioplasty: the PREFACE trial

PubMed Central

Mulder, H; Schalij, M; Kauer, B; Visser, R; van Dijkman, P R M; Jukema, J; Zwinderman, A; Bruschke, A

2001-01-01

OBJECTIVE—To test the hypothesis that the 3-hydroxy-3-methylglutaryl coenzyme-A reductase inhibitor pravastatin ameliorates endothelium mediated responses of dilated coronary segments: the PREFACE (pravastatin related effects following angioplasty on coronary endothelium) trial.
DESIGN—A double blind, randomised, placebo controlled, multicentre study.
SETTING—Four hospitals in the Netherlands.
PATIENTS—63 non-smoking, non-hypercholesterolaemic patients scheduled for elective balloon angioplasty (pravastatin 34, placebo 29).
INTERVENTIONS—The effects of three months of pravastatin treatment (40 mg daily) on endothelium dependent vasomotor function were studied. Balloon angioplasty was undertaken one month after randomisation, and coronary vasomotor function tests using acetylcholine were performed two months after balloon angioplasty. The angiograms were analysed quantitatively.
MAIN OUTCOME MEASURES—The efficacy measure was the acetylcholine induced change in mean arterial diameter, determined in the dilated segment and in an angiographically normal segment of an adjacent non-manipulated coronary artery.
RESULTS—Increasing acetylcholine doses produced vasoconstriction in the dilated segments (p = 0.004) but not in the normal segments. Pravastatin did not affect the vascular response to acetylcholine in either the dilated segments (p = 0.09) or the non-dilated sites. Endothelium dependent vasomotion in normal segments was correlated with that in dilated segments (r = 0.47, p < 0.001). There were fewer procedure related events in the pravastatin group than in the placebo group (p < 0.05).
CONCLUSIONS—Endothelium dependent vasomotion in normal segments is correlated with that in dilated segments. A significant beneficial effect of pravastatin on endothelial function could not be shown, but in the dilated segments there was a trend towards a beneficial treatment effect in the pravastatin group.


Keywords: angioplasty; endothelium; acetylcholine; pravastatin PMID:11602546

Generalizability of findings from randomized controlled trials: application to the National Institute of Drug Abuse Clinical Trials Network.

PubMed

Susukida, Ryoko; Crum, Rosa M; Ebnesajjad, Cyrus; Stuart, Elizabeth A; Mojtabai, Ramin

2017-07-01

To compare randomized controlled trial (RCT) sample treatment effects with the population effects of substance use disorder (SUD) treatment. Statistical weighting was used to re-compute the effects from 10 RCTs such that the participants in the trials had characteristics that resembled those of patients in the target populations. Multi-site RCTs and usual SUD treatment settings in the United States. A total of 3592 patients in 10 RCTs and 1 602 226 patients from usual SUD treatment settings between 2001 and 2009. Three outcomes of SUD treatment were examined: retention, urine toxicology and abstinence. We weighted the RCT sample treatment effects using propensity scores representing the conditional probability of participating in RCTs. Weighting the samples changed the significance of estimated sample treatment effects. Most commonly, positive effects of trials became statistically non-significant after weighting (three trials for retention and urine toxicology and one trial for abstinence); also, non-significant effects became significantly positive (one trial for abstinence) and significantly negative effects became non-significant (two trials for abstinence). There was suggestive evidence of treatment effect heterogeneity in subgroups that are under- or over-represented in the trials, some of which were consistent with the differences in average treatment effects between weighted and unweighted results. The findings of randomized controlled trials (RCTs) for substance use disorder treatment do not appear to be directly generalizable to target populations when the RCT samples do not reflect adequately the target populations and there is treatment effect heterogeneity across patient subgroups. © 2017 Society for the Study of Addiction.

Photobiomodulation with non-thermal lasers: Mechanisms of action and therapeutic uses in dermatology and aesthetic medicine.

PubMed

Nestor, Mark; Andriessen, Anneke; Berman, Brian; Katz, Bruce E; Gilbert, Dore; Goldberg, David J; Gold, Michael H; Kirsner, Robert S; Lorenc, Paul Z

2017-08-01

Non-thermal laser therapy in dermatology, is a growing field in medical technology by which therapeutic effects are achieved by exposing tissues to specific wavelengths of light. The purpose of this review was to gain a better understanding of the science behind non-thermal laser and the evidence supporting its use in dermatology. A group of dermatologists and surgeons recently convened to review the evidence supporting the use of non-thermal laser for body sculpting, improving the appearance of cellulite, and treating onychomycosis. The use of non-thermal laser for body sculpting is supported by three randomized, double-blind, sham-controlled studies (N = 161), one prospective open-label study (N = 54), and two retrospective studies (N = 775). Non-thermal laser application for improving the appearance of cellulite is supported by one randomized, double-blind, sham-controlled study (N = 38). The use of non-thermal laser for the treatment of onychomycosis is supported by an analysis of three non-randomized, open-label studies demonstrating clinical improvement of nails (N = 292). Non-thermal laser is steadily moving into mainstream medical practice, such as dermatology. Although present studies have demonstrated the safety and efficacy of non-thermal laser for body sculpting, cellulite reduction and onychomycosis treatment, studies demonstrating the efficacy of non-thermal laser as a stand-alone procedure are still inadequate.

STICK-SLIP-SEPARATION Analysis and Non-Linear Stiffness and Damping Characterization of Friction Contacts Having Variable Normal Load

NASA Astrophysics Data System (ADS)

Yang, B. D.; Chu, M. L.; Menq, C. H.

1998-03-01

Mechanical systems in which moving components are mutually constrained through contacts often lead to complex contact kinematics involving tangential and normal relative motions. A friction contact model is proposed to characterize this type of contact kinematics that imposes both friction non-linearity and intermittent separation non-linearity on the system. The stick-slip friction phenomenon is analyzed by establishing analytical criteria that predict the transition between stick, slip, and separation of the interface. The established analytical transition criteria are particularly important to the proposed friction contact model for the transition conditions of the contact kinematics are complicated by the effect of normal load variation and possible interface separation. With these transition criteria, the induced friction force on the contact plane and the variable normal load perpendicular to the contact plane, can be predicted for any given cyclic relative motions at the contact interface and hysteresis loops can be produced so as to characterize the equivalent damping and stiffness of the friction contact. These-non-linear damping and stiffness methods along with the harmonic balance method are then used to predict the resonant response of a frictionally constrained two-degree-of-freedom oscillator. The predicted results are compared with those of the time integration method and the damping effect, the resonant frequency shift, and the jump phenomenon are examined.

Systematic review on the health effects of exposure to radiofrequency electromagnetic fields from mobile phone base stations.

PubMed

Röösli, Martin; Frei, Patrizia; Mohler, Evelyn; Hug, Kerstin

2010-12-01

to review and evaluate the recent literature on the health effects of exposure to mobile phone base station (MPBS) radiation. we performed a systematic review of randomized human trials conducted in laboratory settings and of epidemiological studies that investigated the health effects of MPBS radiation in the everyday environment. we included in the analysis 17 articles that met our basic quality criteria: 5 randomized human laboratory trials and 12 epidemiological studies. The majority of the papers (14) examined self-reported non-specific symptoms of ill-health. Most of the randomized trials did not detect any association between MPBS radiation and the development of acute symptoms during or shortly after exposure. The sporadically observed associations did not show a consistent pattern with regard to symptoms or types of exposure. We also found that the more sophisticated the exposure assessment, the less likely it was that an effect would be reported. Studies on health effects other than non-specific symptoms and studies on MPBS exposure in children were scarce. the evidence for a missing relationship between MPBS exposure up to 10 volts per metre and acute symptom development can be considered strong because it is based on randomized, blinded human laboratory trials. At present, there is insufficient data to draw firm conclusions about health effects from long-term low-level exposure typically occurring in the everyday environment.

Current evidence for the safety and efficacy of the bio-engineered dual therapy COMBO stent.

PubMed

Kalkman, Deborah N; Chandrasekhar, Jaya; de Winter, Robbert J; Mehran, Roxana

2018-06-01

The novel dual-therapy COMBO stent aims to promote vessel healing after percutaneous coronary intervention (PCI) in patients with coronary artery disease. The pro-healing technique consists of an anti-CD34+ antibody layer that attracts circulating endothelial progenitor cells (EPCs), which bind to the stent surface and allow rapid endothelialization by differentiation of the EPCs into normal endothelial cells. The COMBO stent combines this pro-healing technique with an abluminal drug elution of sirolimus. The promise of this dual-therapy stent is that it may safely allow a shortened duration of dual-antiplatelet therapy (DAPT) after stent placement. Moreover, with a mature endothelial layer, lower rates of in-stent restenosis may be expected. Clinical outcomes after COMBO stent implantation have been recently evaluated in both randomized trials and large, prospective, multicenter registries, showing low clinical event rates of in-stent restenosis and stent thrombosis. Randomized clinical trials (HARMONEE and RECOVERY) have demonstrated the non-inferiority of COMBO versus "first in class" second generation and newer generation drug-eluting stents. Safety and efficacy of 3 months of DAPT after COMBO stent placement in patients presenting with acute coronary syndrome has been evaluated in the large REDUCE randomized controlled trial, showing non-inferiority to standard duration of 12-month DAPT. In this review we provide an overview of the current pre-clinical and clinical evidence for the performance of the COMBO stent.

The effect of mitomycin C trabeculectomy on the progression of visual field defect in normal-tension glaucoma.

PubMed

Hagiwara, Y; Yamamoto, T; Kitazawa, Y

2000-03-01

We investigated in a prospective fashion the visual prognosis and complications in normal-tension glaucoma following unilateral trabeculectomy with adjunctive mitomycin C. Trabeculectomy with adjunctive mitomycin C was carried out unilaterally in 21 cases of normal-tension glaucoma. Intraocular pressure (IOP), visual prognosis, and complications were compared between the operated eyes and the non-operated fellow eyes. The follow-up period ranged from 2 to 7 years. The IOP dropped significantly from 14.8+/-1.8 mmHg (mean +/- SD) to 9.6+/-3.9 mmHg in the operated eyes (P=0.0002, Wilcoxon signed-rank test), but did not drop in the non-operated eyes. The mean deviation (MD) was -12.69+/-6.41 dB preoperatively and -14.70+/-5.49 dB at the last clinic visit in the operated eyes, whereas in non-operated eyes it was -7.85+/-5.65 dB and -11.15+/-5.62 dB, respectively. The MD deteriorated significantly in both operated and non-operated eyes (operated eyes P=0.0239, non-operated eyes: P=0.0002; Wilcoxon signed-rank test). The MD slope was -0.37+/-0.60 dB/year and -0.71+/-0.89 dB/year for the operated and non-operated eyes, respectively (P=0.5243, Mann-Whitney U-test). Visual field deterioration was more frequently observed in the non-operated eyes by a pointwise definition of the progression (P<0.05, McNemar test). Visual acuity deteriorated in 6 of the operated eyes and in 5 of the non-operated eyes. Cataract developed in 6 (29%) of the 21 operated eyes, while among the non-operated eyes 4 (19%) developed cataract. Mitomycin C trabeculectomy is effective in delaying progression of visual field defect in normal-tension glaucoma, but complications may arise and cause some visual disturbance.

Quenched bond randomness: Superfluidity in porous media and the strong violation of universality

DOE Office of Scientific and Technical Information (OSTI.GOV)

Falicov, A.; Berker, A.N.

1997-04-01

The effects of quenched bond randomness are most readily studied with superfluidity immersed in a porous medium. A lattice model for {sup 3}He-{sup 4}He mixtures and incomplete {sup 4}He fillings in aerogel yields the signature effect of bond randomness, namely the conversion of symmetry-breaking first-order phase transitions into second-order phase transitions, the A-line reaching zero temperature, and the elimination of non-symmetry-breaking first-order phase transitions. The model recognizes the importance of the connected nature of aerogel randomness and thereby yields superfluidity at very low {sup 4}He concentrations, a phase separation entirely within the superfluid phase, and the order-parameter contrast between mixturesmore » and incomplete fillings, all in agreement with experiments. The special properties of the helium mixture/aerogel system are distinctly linked to the aerogel properties of connectivity, randomness, and tenuousness, via the additional study of a regularized {open_quote}jungle-gym{close_quotes} aerogel. Renormalization-group calculations indicate that a strong violation of the empirical universality principle of critical phenomena occurs under quenched bond randomness. It is argued that helium/aerogel critical properties reflect this violation and further experiments are suggested. Renormalization-group analysis also shows that, adjoiningly to the strong universality violation (which hinges on the occurrence or non-occurrence of asymptotic strong coupling-strong randomness under resealing), there is a new {open_quotes}hyperuniversality{close_quotes} at phase transitions with asymptotic strong coupling-strong randomness behavior, for example assigning the same critical exponents to random-bond tricriticality and random-field criticality.« less

Increased entropy of signal transduction in the cancer metastasis phenotype.

PubMed

Teschendorff, Andrew E; Severini, Simone

2010-07-30

The statistical study of biological networks has led to important novel biological insights, such as the presence of hubs and hierarchical modularity. There is also a growing interest in studying the statistical properties of networks in the context of cancer genomics. However, relatively little is known as to what network features differ between the cancer and normal cell physiologies, or between different cancer cell phenotypes. Based on the observation that frequent genomic alterations underlie a more aggressive cancer phenotype, we asked if such an effect could be detectable as an increase in the randomness of local gene expression patterns. Using a breast cancer gene expression data set and a model network of protein interactions we derive constrained weighted networks defined by a stochastic information flux matrix reflecting expression correlations between interacting proteins. Based on this stochastic matrix we propose and compute an entropy measure that quantifies the degree of randomness in the local pattern of information flux around single genes. By comparing the local entropies in the non-metastatic versus metastatic breast cancer networks, we here show that breast cancers that metastasize are characterised by a small yet significant increase in the degree of randomness of local expression patterns. We validate this result in three additional breast cancer expression data sets and demonstrate that local entropy better characterises the metastatic phenotype than other non-entropy based measures. We show that increases in entropy can be used to identify genes and signalling pathways implicated in breast cancer metastasis and provide examples of de-novo discoveries of gene modules with known roles in apoptosis, immune-mediated tumour suppression, cell-cycle and tumour invasion. Importantly, we also identify a novel gene module within the insulin growth factor signalling pathway, alteration of which may predispose the tumour to metastasize. These results demonstrate that a metastatic cancer phenotype is characterised by an increase in the randomness of the local information flux patterns. Measures of local randomness in integrated protein interaction mRNA expression networks may therefore be useful for identifying genes and signalling pathways disrupted in one phenotype relative to another. Further exploration of the statistical properties of such integrated cancer expression and protein interaction networks will be a fruitful endeavour.

Tips and Tricks for Successful Application of Statistical Methods to Biological Data.

PubMed

Schlenker, Evelyn

2016-01-01

This chapter discusses experimental design and use of statistics to describe characteristics of data (descriptive statistics) and inferential statistics that test the hypothesis posed by the investigator. Inferential statistics, based on probability distributions, depend upon the type and distribution of the data. For data that are continuous, randomly and independently selected, as well as normally distributed more powerful parametric tests such as Student's t test and analysis of variance (ANOVA) can be used. For non-normally distributed or skewed data, transformation of the data (using logarithms) may normalize the data allowing use of parametric tests. Alternatively, with skewed data nonparametric tests can be utilized, some of which rely on data that are ranked prior to statistical analysis. Experimental designs and analyses need to balance between committing type 1 errors (false positives) and type 2 errors (false negatives). For a variety of clinical studies that determine risk or benefit, relative risk ratios (random clinical trials and cohort studies) or odds ratios (case-control studies) are utilized. Although both use 2 × 2 tables, their premise and calculations differ. Finally, special statistical methods are applied to microarray and proteomics data, since the large number of genes or proteins evaluated increase the likelihood of false discoveries. Additional studies in separate samples are used to verify microarray and proteomic data. Examples in this chapter and references are available to help continued investigation of experimental designs and appropriate data analysis.

A randomized, crossover pharmacokinetic study comparing generic tacrolimus vs. the reference formulation in subpopulations of kidney transplant patients.

PubMed

Bloom, R D; Trofe-Clark, J; Wiland, A; Alloway, R R

2013-01-01

An exploratory, post hoc analysis was performed using data from a prospective, multicenter, open-label, randomized, two-period (14 d per period), two-sequence, crossover, steady-state pharmacokinetic study comparing generic tacrolimus (Sandoz) vs. reference tacrolimus in stable renal transplant patients receiving their pre-study twice-daily dose. Pharmacokinetic parameters were compared in 68 patients according to gender, African American ethnicity, the presence or absence of diabetes, and use of steroids. The ratios of tacrolimus AUC0-12 h , Cmax , and C12 with generic vs. reference tacrolimus were calculated using the geometric mean (GM) of dose-normalized values at days 14 and 28. Mean (SD) tacrolimus dose at baseline was 5.7 (4.2) mg/d. There were no consistent differences in dose-normalized AUC0-12 h , C12 , Cmax, or tmax between the generic and reference preparations within subpopulations. The 90% confidence intervals (CI) for the ratios of dose-normalized AUC0-12 h and C12 with generic vs. reference tacrolimus were within 80-125% for all subpopulations, as were 90% CIs for Cmax other than for females, African Americans, and non-diabetics, which is not unexpected given the wide variability of tacrolimus Cmax and the small subpopulation sizes. These exploratory results suggest that this generic tacrolimus preparation would be expected to offer comparable bioavailability to the reference drug in these patient subpopulations. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Fundamental movement skills in preschoolers: a randomized controlled trial targeting object control proficiency.

PubMed

Donath, L; Faude, O; Hagmann, S; Roth, R; Zahner, L

2015-11-01

Adequately developed fundamental movement skills, particularly object control dimensions, are considered essential to learn more complex movement patterns and to increase the likelihood to successfully participate in organized and non-organized sports during later years. Thus, the present randomized controlled trial aimed at improving object control dimensions at an early state in a kindergarten setting. Catching, throwing, kicking, rolling and stationary dribbling were assessed via gross motor development 2 (TGMD-2) testing in 41 normally developed preschoolers. On a cluster-randomized basis [strata: age, sex and body mass index (BMI)], three kindergartens were randomly assigned to an intervention group (n = 22, INT, age: 4.6 ± 1.0 years; BMI: 16.2 ± 1.1 kg/m(2) ) and three to a control group (n = 19, CON: age: 4.5 ± 1.2 years; BMI: 16.8 ± 1.2 kg/m(2) ). Twelve structured training sessions were given within 6 weeks (12 sessions). The total training volume was 330 min. Moderate time × group interaction were observed for the total sum score (Δ+22%, P = 0.05) and dribbling (Δ+41%, P = 0.002). Adjusting for baseline differences analyses of covariance did not affect these results. Interestingly, likely to most likely practically worthwhile effects were detected for the total sum score, catching and dribbling. Object control dimensions such as dribbling and catching that apparently rely on rhythmical movement patterns and anticipatory eye-hand coordination seem to benefit from short-term object control training. These skills are considered important for successful team-sport participation and appropriate sportive motor development. © 2015 John Wiley & Sons Ltd.

Prophylactic intra-peritoneal drain placement following pancreaticoduodenectomy: A systematic review and meta-analysis

PubMed Central

Wang, Yi-Chao; Szatmary, Peter; Zhu, Jing-Qiang; Xiong, Jun-Jie; Huang, Wei; Gomatos, Ilias; Nunes, Quentin M; Sutton, Robert; Liu, Xu-Bao

2015-01-01

AIM: To conduct a meta-analysis comparing outcomes after pancreaticoduodenectomy (PD) with or without prophylactic drainage. METHODS: Relevant comparative randomized and non-randomized studies were systemically searched based on specific inclusion and exclusion criteria. Postoperative outcomes were compared between patients with and those without routine drainage. Pooled odds ratios (OR) with 95%CI were calculated using either fixed effects or random effects models. RESULTS: One randomized controlled trial and four non-randomized comparative studies recruiting 1728 patients were analyzed. Patients without prophylactic drainage after PD had significantly higher mortality (OR = 2.32, 95%CI: 1.11-4.85; P = 0.02), despite the fact that they were associated with fewer overall complications (OR = 0.62, 95%CI: 0.48-0.82; P = 0.00), major complications (OR = 0.75, 95%CI: 0.60-0.93; P = 0.01) and readmissions (OR = 0.77, 95%CI: 0.60-0.98; P = 0.04). There were no significant differences in the rates of pancreatic fistula, intra-abdominal abscesses, postpancreatectomy hemorrhage, biliary fistula, delayed gastric emptying, reoperation or radiologic-guided drains between the two groups. CONCLUSION: Indiscriminate abandonment of intra-abdominal drainage following PD is associated with greater mortality, but lower complication rates. Future randomized trials should compare routine vs selective drainage. PMID:25741162

H∞ control for uncertain linear system over networks with Bernoulli data dropout and actuator saturation.

PubMed

Yu, Jimin; Yang, Chenchen; Tang, Xiaoming; Wang, Ping

2018-03-01

This paper investigates the H ∞ control problems for uncertain linear system over networks with random communication data dropout and actuator saturation. The random data dropout process is modeled by a Bernoulli distributed white sequence with a known conditional probability distribution and the actuator saturation is confined in a convex hull by introducing a group of auxiliary matrices. By constructing a quadratic Lyapunov function, effective conditions for the state feedback-based H ∞ controller and the observer-based H ∞ controller are proposed in the form of non-convex matrix inequalities to take the random data dropout and actuator saturation into consideration simultaneously, and the problem of non-convex feasibility is solved by applying cone complementarity linearization (CCL) procedure. Finally, two simulation examples are given to demonstrate the effectiveness of the proposed new design techniques. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

Non-volatile magnetic random access memory

NASA Technical Reports Server (NTRS)

Katti, Romney R. (Inventor); Stadler, Henry L. (Inventor); Wu, Jiin-Chuan (Inventor)

1994-01-01

Improvements are made in a non-volatile magnetic random access memory. Such a memory is comprised of an array of unit cells, each having a Hall-effect sensor and a thin-film magnetic element made of material having an in-plane, uniaxial anisotropy and in-plane, bipolar remanent magnetization states. The Hall-effect sensor is made more sensitive by using a 1 m thick molecular beam epitaxy grown InAs layer on a silicon substrate by employing a GaAs/AlGaAs/InAlAs superlattice buffering layer. One improvement avoids current shunting problems of matrix architecture. Another improvement reduces the required magnetizing current for the micromagnets. Another improvement relates to the use of GaAs technology wherein high electron-mobility GaAs MESFETs provide faster switching times. Still another improvement relates to a method for configuring the invention as a three-dimensional random access memory.

Inbreeding avoidance through non-random mating in sticklebacks

PubMed Central

Frommen, Joachim G; Bakker, Theo C.M

2006-01-01

Negative effects of inbreeding are well documented in a wide range of animal taxa. Hatching success and survival of inbred offspring is reduced in many species and inbred progeny are often less attractive to potential mates. Thus, individuals should avoid mating with close kin. However, experimental evidence for inbreeding avoidance through non-random mating in vertebrates is scarce. Here, we show that gravid female three-spined sticklebacks (Gasterosteus aculeatus) when given the choice between a courting familiar brother and a courting unfamiliar non-sib prefer to mate with the non-sib and thus avoid the disadvantages of incest. We controlled for differences in males' body size and red intensity of nuptial coloration. Thus, females adjust their courting behaviour to the risk of inbreeding. PMID:17148370

Inbreeding avoidance through non-random mating in sticklebacks.

PubMed

Frommen, Joachim G; Bakker, Theo C M

2006-06-22

Negative effects of inbreeding are well documented in a wide range of animal taxa. Hatching success and survival of inbred offspring is reduced in many species and inbred progeny are often less attractive to potential mates. Thus, individuals should avoid mating with close kin. However, experimental evidence for inbreeding avoidance through non-random mating in vertebrates is scarce. Here, we show that gravid female three-spined sticklebacks (Gasterosteus aculeatus) when given the choice between a courting familiar brother and a courting unfamiliar non-sib prefer to mate with the non-sib and thus avoid the disadvantages of incest. We controlled for differences in males' body size and red intensity of nuptial coloration. Thus, females adjust their courting behaviour to the risk of inbreeding.

Plasticity-Driven Self-Organization under Topological Constraints Accounts for Non-random Features of Cortical Synaptic Wiring

PubMed Central

Miner, Daniel; Triesch, Jochen

2016-01-01

Understanding the structure and dynamics of cortical connectivity is vital to understanding cortical function. Experimental data strongly suggest that local recurrent connectivity in the cortex is significantly non-random, exhibiting, for example, above-chance bidirectionality and an overrepresentation of certain triangular motifs. Additional evidence suggests a significant distance dependency to connectivity over a local scale of a few hundred microns, and particular patterns of synaptic turnover dynamics, including a heavy-tailed distribution of synaptic efficacies, a power law distribution of synaptic lifetimes, and a tendency for stronger synapses to be more stable over time. Understanding how many of these non-random features simultaneously arise would provide valuable insights into the development and function of the cortex. While previous work has modeled some of the individual features of local cortical wiring, there is no model that begins to comprehensively account for all of them. We present a spiking network model of a rodent Layer 5 cortical slice which, via the interactions of a few simple biologically motivated intrinsic, synaptic, and structural plasticity mechanisms, qualitatively reproduces these non-random effects when combined with simple topological constraints. Our model suggests that mechanisms of self-organization arising from a small number of plasticity rules provide a parsimonious explanation for numerous experimentally observed non-random features of recurrent cortical wiring. Interestingly, similar mechanisms have been shown to endow recurrent networks with powerful learning abilities, suggesting that these mechanism are central to understanding both structure and function of cortical synaptic wiring. PMID:26866369

Ribavirin for treating Crimean Congo haemorrhagic fever.

PubMed

Johnson, Samuel; Henschke, Nicholas; Maayan, Nicola; Mills, Inga; Buckley, Brian S; Kakourou, Artemisia; Marshall, Rachel

2018-06-05

Crimean Congo haemorrhagic fever (CCHF) is a tick-borne disease that occurs in parts of Asia, Europe and Africa. Since 2000 the infection has caused epidemics in Turkey, Iran, Russia, Uganda and Pakistan. Good-quality general supportive medical care helps reduce mortality. There is uncertainty and controversy about treating CCHF with the antiviral drug ribavirin. To assess the effects of ribavirin for treating people with Crimean Congo haemorrhagic fever. We searched the Cochrane Infectious Diseases Group Specialized Register; the Central Register of Controlled Trials (CENTRAL); MEDLINE (PubMed); Embase (OVID); Science Citation Index-Expanded, Social Sciences Citation index, conference proceedings (Web of Science); and CINAHL (EBSCOHost). We also searched the WHO International Clinical Trials Registry Platform (ICTRP) and ClinicalTrials.gov for trials in progress. We conducted all searches up to 16 October 2017. We also contacted experts in the field and obtained further studies from these sources. We evaluated studies assessing the use of ribavirin in people with suspected or confirmed Crimean Congo haemorrhagic fever. We included randomised control trials (RCTs); non-randomised studies (NRSs) that included more than 10 participants designed as cohort studies with comparators; and case-control studies. Two review authors assessed eligibility, risk of bias, and extracted data. For non-randomized studies we used the ROBINS-I tool to assess risk of bias. The main effects analysis included all studies where we judged the risk of bias to be low, moderate or high. We summarized dichotomous outcomes using risk ratios (RRs) and continuous outcomes using mean differences (MDs), and used meta-analyses where appropriate. We carried out a subsidiary appraisal and analysis of studies with critical risk of bias for the primary outcome, as these are often cited to support using ribavirin. For the main effects analysis, five studies met our inclusion criteria: one RCT with 136 participants and four non-randomized studies with 612 participants. We excluded 18 non-randomized studies with critical risk of bias, where none had attempted to control for confounding.We do not know if ribavirin reduces mortality (1 RCT; RR 1.13, 95% confidence interval (CI) 0.29 to 4.32; 136 participants; very low-certainty evidence; 3 non-randomized studies; RR 0.72, 95% CI 0.41 to 1.28; 549 participants; very low-certainty evidence). We do not know if ribavirin reduces the length of stay in hospital (1 RCT: mean difference (MD) 0.70 days, 95% CI -0.39 to 1.79; 136 participants; and 1 non-randomized study: MD -0.80, 95% CI -2.70 to 1.10; 50 participants; very low-certainty evidence). We do not know if it reduces the risk of patients needing platelet transfusions (1 RCT: RR 1.23, 95% CI 0.77 to 1.96; 136 participants; very low-certainty evidence). For adverse effects (including haemolytic anaemia and a need to discontinue treatment), we do not know whether there is an increased risk with ribavirin in people with CCHF as data are insufficient.We do not know if adding ribavirin to early supportive care improves outcomes. One non-randomized study assessed mortality in people receiving ribavirin and supportive care within four days or less from symptom onset compared to after four days since symptom onset: mortality was lower in the group receiving early supportive care and ribavirin, but it is not possible to distinguish between the effects of ribavirin and early supportive medical care alone.In the subsidiary analysis, 18 studies compared people receiving ribavirin with those not receiving ribavirin. All had a critical risk of bias due to confounding, reflected in the mortality point estimates favouring ribavirin. We do not know if ribavirin is effective for treating Crimean Congo haemorrhagic fever. Non-randomized studies are often cited as evidence of an effect, but the risk of bias in these studies is high.

Effect of Jiangzhi tablet on gastrointestinal propulsive function in mice

NASA Astrophysics Data System (ADS)

Wang, Xiangrong; Geng, Xiuli; Zhao, Jingsheng; Fan, Lili; Zhang, Zhengchen

2018-04-01

This paper aims to study the effect of lipid-lowering tablets on gastric emptying and small intestinal propulsion in mice. Mice were randomly divided into control group, Digestant Pill group, Jiangzhi tablet group, middle dose and small dose, the mice gastric emptying phenolsulfonphthalein, gastric residual rate of phenol red indicator to evaluate the gastric emptying rate, residual rate of detection in mouse stomach; small intestine propulsion and selection of carbon ink as the experimental index. Effects were observed to promote the function of normal mice gastric emptying and intestine. The gastric emptying and small intestinal motor function of normal mice were all promoted by each administration group, and the effect was most obvious in small dose group. The effect of reducing blood lipid on gastrointestinal motility of mice ware obviously enhanced.

The effect of valsartan versus non-RAAS treatment on autoregulation of cerebral blood flow.

PubMed

Périard, Daniel; Rey, Marie-Antoinette; Casagrande, Damien; Vesin, Jean-Marc; Carrera, Emmanuel; Hayoz, Daniel

2012-01-01

Cerebral autoregulation (CA) is a protective mechanism which maintains the steadiness of the cerebral blood flow (CBF) through a broad range of systemic blood pressure (BP). Acute hypertension has been shown to reduce the cerebrovascular adaptation to BP variations. However, it is still unknown whether CA is impaired in chronic hypertension. This study evaluated whether a strict control of BP affects the CA in patients with chronic hypertension, and compared a valsartan-based regimen to a regimen not inhibiting the renin-angiotensin-aldosterone system (non-RAAS). Eighty untreated patients with isolated systolic hypertension were randomized to valsartan 320 mg or to a non-RAAS regimen during 6 months. The medication was upgraded to obtain BP <140/90 mm Hg. Continuous recordings of arterial BP and CBF velocity (transcranial Doppler) were performed during periods of 5 minutes, at rest, and at different levels of alveolar CO(2) pressure provided by respiratory maneuvers. The dominant frequency of CBF oscillations was determined for each patient. Dynamic CA was measured as the mean phase shift between BP and CBF by cross-spectral analysis in the medium frequency and in the dominant CBF frequency. Mean ambulatory 24-hour BP fell from 144/87 to 127/79 mm Hg in the valsartan group and from 144/87 to 134/81 mm Hg in the non-RAAS group (p = 0.13). Both groups had a similar reduction in the central BP and in the carotido-femoral pulse wave velocity. The average phase shift between BP fluctuations and CBF response at rest was normal at randomization (1.82 ± 0.08 s), which is considered a preserved autoregulation and increased to 1.91 ± 0.12 s at the end of study (p = 0.45). The comparison of both treatments showed no significant difference (-0.01 ± 0.17 s vs. 0.16 ± 0.16 s, p = 0.45) for valsartan versus non-RAAS groups. The plasmatic level of glycosylated hemoglobin decreased in the valsartan arm compared to the non-RAAS arm (-0.23 ± 0.06 vs. -0.08 ± 0.07%, p = 0.07). In elderly hypertensive men with isolated chronic systolic hypertension, CA seems efficient at baseline and is not significantly affected by 6 months of BP-lowering treatment. This suggests that the preventive effects of BP medication against stroke are not mediated through a restoration of the CA. Copyright © 2012 S. Karger AG, Basel.

Prevention of Pulmonary Fibrosis via Trichostatin A (TSA) in Bleomycin Induced Rats.

PubMed

Ye, Qing; Li, Yanqin; Jiang, Handong; Xiong, Jianfei; Xu, Jiabo; Qin, Hui; Liu, Bin

2014-10-20

To investigate the effects of non selective histone deacetylase inhibitors Trichostatin A (TSA)on bleomycin-induced pulmonary fibrosis. To investigate the effects of non selective histone deacetylase inhibitors Trichostatin A ( TSA ) on HDAC2, p-SMAD2, HDAC2 mRNA, SMAD2mRNA in pulmonary fibrosis rats and investigate impossible mechanism. 46 SPF level male SD rats were randomly divided into four groups: ten for normal control group, fourteen for model control group I, twelve for model control group II and ten for treatment group. Rat pulmonary fibrosis was induced by bleomycin(5mg/kg) via single intratracheal perfusion in the two model control groups and treatment group. Normal control mice were instilled with a corresponding volume of 0.9% saline intratracheally. Treatment group was treated by the dilution of TSA 2mg/kg DMSO 60ul and0.9% saline 1.2ml intraperitoneal injection from the next day ,once a day for three days. Model control group II was treated by the dilution of DMSO 60ul and0.9% saline 1.2ml intraperitoneal injection from the next day once a day for three days. Model control group I and normal control group were treated by 0.9% saline 1.2ml intraperitoneal injection from the next day once a day for three days. All the animals were sacrificed on the 21 day after modeling. The pathological changes were observed by hematoxylin and eosin(HE)stain and masson trichrome stain. The expression of HDAC2 mRNA,SMAD2 mRNA were measured by real-time PCR. The protein level of HDAC2 and p-SMAD2 in serum was measured by Western blot. The pulmonary fibrosis in treatment group were significantly alleviated compared to the two model control groups (P<0.05). Real-time PCR showed that the treatment group had lower expression of lung tissue HDAC2 mRNA than the two model control groups and normal control group (P<0.05). The expression of lung tissue SMAD2 mRNA increased in the two model control groups and treatment group (P<0.05),but there were no significant differences among the three groups(P>0.05). Western blot indicated that the protein level of HDAC2 and p-SMAD2 in serum increased in the two model control groups compared with normal control group(P<0.05).But treatment group had lower protein level of HDAC2 (P<0.05) and no significant difference in the protein level of p-SMAD2 compared to the two model control groups (P>0.05). Non selective histone deacetylase inhibitors of Trichostatin A (TSA) can reduce the bleomycin induced pulmonary fibrosis in rats. TSA attenuates pulmonary fibrosis and it can inhibit HDAC2 expression at the gene and protein level. Bleomycin induced fibrosis has the relationship with p-SMAD2 in gene and protein levels, but TSA inhibit bleomycin-induced lung fibrosis effect with no relation with SMAD2 phosphorylation pathways.

The Metabolic and Endocrine Response and Health Implications of Consuming Sugar-Sweetened Beverages: Findings From Recent Randomized Controlled Trials123

PubMed Central

Rippe, James M.

2013-01-01

Fructose-containing sugars, including fructose itself, high fructose corn syrup (HFCS), and sucrose have engendered considerable controversy. The effects of HFCS and sucrose in sugar-sweetened beverages, in particular, have generated intense scientific debate that has spilled over to the public. This controversy is related to well-known differences in metabolism between fructose and glucose in the liver. In addition, research studies have often been conducted comparing pure fructose and pure glucose even though neither is consumed to any appreciable degree in isolation in the human diet. Other evidence has been drawn from animal studies and epidemiologic or cohort studies. Few randomized controlled trials (RCTs) have compared HFCS with sucrose (the 2 sugars most commonly consumed in the human diet) at dosage amounts within the normal human consumption range. This review compares results of recently concluded RCTs with other forms of evidence related to fructose, HFCS, and sucrose. We conclude that great caution must be used when suggesting adverse health effects of consuming these sugars in the normal way they are consumed and at the normal amounts in the human diet, because RCTs do not support adverse health consequences at these doses when employing these sugars. PMID:24228199

An analysis of the effect of funding source in randomized clinical trials of second generation antipsychotics for the treatment of schizophrenia.

PubMed

Montgomery, John H; Byerly, Matthew; Carmody, Thomas; Li, Baitao; Miller, Daniel R; Varghese, Femina; Holland, Rhiannon

2004-12-01

The effect of funding source on the outcome of randomized controlled trials has been investigated in several medical disciplines; however, psychiatry has been largely excluded from such analyses. In this article, randomized controlled trials of second generation antipsychotics in schizophrenia are reviewed and analyzed with respect to funding source (industry vs. non-industry funding). A literature search was conducted for randomized, double-blind trials in which at least one of the tested treatments was a second generation antipsychotic. In each study, design quality and study outcome were assessed quantitatively according to rating scales. Mean quality and outcome scores were compared in the industry-funded studies and non-industry-funded studies. An analysis of the primary author's affiliation with industry was similarly performed. Results of industry-funded studies significantly favored second generation over first generation antipsychotics when compared to non-industry-funded studies. Non-industry-funded studies showed a trend toward higher quality than industry-funded studies; however, the difference between the two was not significant. Also, within the industry-funded studies, outcomes of trials involving first authors employed by industry sponsors demonstrated a trend toward second generation over first generation antipsychotics to a greater degree than did trials involving first authors employed outside the industry (p=0.05). While the retrospective design of the study limits the strength of the findings, the data suggest that industry bias may occur in randomized controlled trials in schizophrenia. There appears to be several sources by which bias may enter clinical research, including trial design, control of data analysis and multiplicity/redundancy of trials.

Issues Relating to Selective Reporting When Including Non-Randomized Studies in Systematic Reviews on the Effects of Healthcare Interventions

ERIC Educational Resources Information Center

Norris, Susan L.; Moher, David; Reeves, Barnaby C.; Shea, Beverley; Loke, Yoon; Garner, Sarah; Anderson, Laurie; Tugwell, Peter; Wells, George

2013-01-01

Background: Selective outcome and analysis reporting (SOR and SAR) occur when only a subset of outcomes measured and analyzed in a study is fully reported, and are an important source of potential bias. Key methodological issues: We describe what is known about the prevalence and effects of SOR and SAR in both randomized controlled trials (RCTs)…

Does Increased Exercise or Physical Activity Alter Ad-Libitum Daily Energy Intake or Macronutrient Composition in Healthy Adults? A Systematic Review

PubMed Central

Donnelly, Joseph E.; Herrmann, Stephen D.; Lambourne, Kate; Szabo, Amanda N.; Honas, Jeffery J.; Washburn, Richard A.

2014-01-01

Background The magnitude of the negative energy balance induced by exercise may be reduced due to compensatory increases in energy intake. Objective To address the question: Does increased exercise or physical activity alter ad-libitum daily energy intake or macronutrient composition in healthy adults? Data Sources PubMed and Embase were searched (January 1990–January 2013) for studies that presented data on energy and/or macronutrient intake by level of exercise, physical activity or change in response to exercise. Ninety-nine articles (103 studies) were included. Study Eligibility Criteria Primary source articles published in English in peer-reviewed journals. Articles that presented data on energy and/or macronutrient intake by level of exercise or physical activity or changes in energy or macronutrient intake in response to acute exercise or exercise training in healthy (non-athlete) adults (mean age 18–64 years). Study Appraisal and Synthesis Methods Articles were grouped by study design: cross-sectional, acute/short term, non-randomized, and randomized trials. Considerable heterogeneity existed within study groups for several important study parameters, therefore a meta-analysis was considered inappropriate. Results were synthesized and presented by study design. Results No effect of physical activity, exercise or exercise training on energy intake was shown in 59% of cross-sectional studies (n = 17), 69% of acute (n = 40), 50% of short-term (n = 10), 92% of non-randomized (n = 12) and 75% of randomized trials (n = 24). Ninety-four percent of acute, 57% of short-term, 100% of non-randomized and 74% of randomized trials found no effect of exercise on macronutrient intake. Forty-six percent of cross-sectional trials found lower fat intake with increased physical activity. Limitations The literature is limited by the lack of adequately powered trials of sufficient duration, which have prescribed and measured exercise energy expenditure, or employed adequate assessment methods for energy and macronutrient intake. Conclusions We found no consistent evidence that increased physical activity or exercise effects energy or macronutrient intake. PMID:24454704

[The Effects of Neurofeedback Training on Physical, Psychoemotional Stress Response and Self-Regulation for Late Adolescence: A Non-Randomized Trial].

PubMed

Choi, Moon Ji; Park, Wan Ju

2018-04-01

The aim of this study was to analyze the effects of neurofeedback training for reducing stress and enhancing self-regulation in late adolescence to identify the possibility of use for nursing intervention. A nonequivalent control group pre-post quasi-experimental design was used. Participants were 78 late adolescents assigned to the experimental group (n=39) that received the neurofeedback training and the control group (n=39). Data were collected on heart rate variability (HRV) and skin conductance level (SCL) to assess stress-biomarker response. The questionnaire contained 164 items from: Positive and Negative Affect Schedule (PANAS), Symptom Checklist-90-Revised (SCL-90-R) and Self-regulatory Ability scale. The neurofeedback training was based on the general adaptation syndrome and body-mind medicine. The intervention was conducted in a total of 10 sessions for 30 minutes per session with high-beta, theta and sensory motor rhythm training on scalp at central zero. There were significant difference in standard deviation of normal to normal interval (p=.036) in HRV and SCL (p=.029) of stress-biomarker response between the two groups. Negative affect (p=.036) in PANAS and obsessive compulsive (p=.023) and depression (p<.001) in SCL-90-R were statistically significant. Self-regulation mode (p=.004) in self-regulation ability scale showed a significant difference between the two groups. The results indicated that the neurofeedback training is effective in stress-biomarkers, psychoemotional stress response and self-regulation. Therefore, neurofeedback training using neuroscientific approach based on brain-mind-body model can be used as an effective nursing intervention for late adolescents in clinics and communities for effective stress responses. © 2018 Korean Society of Nursing Science.

Computing simulated endolymphatic flow thermodynamics during the caloric test using normal and hydropic duct models.

PubMed

Rey-Martinez, Jorge; McGarvie, Leigh; Pérez-Fernández, Nicolás

2017-03-01

The obtained simulations support the underlying hypothesis that the hydrostatic caloric drive is dissipated by local convective flow in a hydropic duct. To develop a computerized model to simulate and predict the internal fluid thermodynamic behavior within both normal and hydropic horizontal ducts. This study used a computational fluid dynamics software to simulate the effects of cooling and warming of two geometrical models representing normal and hydropic ducts of one semicircular horizontal canal during 120 s. Temperature maps, vorticity, and velocity fields were successfully obtained to characterize the endolymphatic flow during the caloric test in the developed models. In the normal semicircular canal, a well-defined endolymphatic linear flow was obtained, this flow has an opposite direction depending only on the cooling or warming condition of the simulation. For the hydropic model a non-effective endolymphatic flow was predicted; in this model the velocity and vorticity fields show a non-linear flow, with some vortices formed inside the hydropic duct.

Does a diet low in FODMAPs reduce symptoms associated with functional gastrointestinal disorders? A comprehensive systematic review and meta-analysis.

PubMed

Marsh, Abigail; Eslick, Enid M; Eslick, Guy D

2016-04-01

Functional gastrointestinal symptoms such as abdominal pain, bloating, distension, constipation, diarrhea and flatulence have been noted in patients with irritable bowel syndrome (IBS) or inflammatory bowel disease (IBD). The diversity of symptoms has meant that finding an effective treatment has been challenging with most treatments alleviating only the primary symptom. A novel treatment option for IBS and IBD currently generating much excitement is the low fermentable, oligo-, di-, mono-saccharides and polyol (FODMAP) diet. The aim of this meta-analysis was to determine the evidence of the efficacy of such a diet in the treatment of functional gastrointestinal symptoms. Electronic databases were searched through to March 2015 to identify relevant studies. Pooled odds ratios (ORs) and 95 % confidence intervals were calculated for the effect of a low FODMAP diet on the reduction in IBS [Symptoms Severity Score (SSS)] score and increase in IBS quality of life (QOL) score for both randomized clinical trials (RCTs) and non-randomized interventions using a random-effects model. Six RCTs and 16 non-randomized interventions were included in the analysis. There was a significant decrease in IBS SSS scores for those individuals on a low FODMAP diet in both the RCTs (OR 0.44, 95 % CI 0.25-0.76; I (2) = 35.52, p = 0.00) and non-randomized interventions (OR 0.03, 95 % CI 0.01-0.2; I (2) = 69.1, p = 0.02). In addition, there was a significant improvement in the IBS-QOL score for RCTs (OR 1.84, 95 % CI 1.12-3.03; I (2) = 0.00, p = 0.39) and for non-randomized interventions (OR 3.18, 95 % CI 1.60-6.31; I (2) = 0.00, p = 0.89). Further, following a low FODMAP diet was found to significantly reduce symptom severity for abdominal pain (OR 1.81, 95 % CI 1.13-2.88; I (2) = 0.00, p = 0.56), bloating (OR 1.75, 95 % CI 1.07-2.87; I (2) = 0.00, p = 0.45) and overall symptoms (OR 1.81, 95 % CI 1.11-2.95; I (2) = 0.00, p = 0.4) in the RCTs. In the non-randomized interventions similar findings were observed. The present meta-analysis supports the efficacy of a low FODMAP diet in the treatment of functional gastrointestinal symptoms. Further research should ensure studies include dietary adherence, and more studies looking at greater number of patients and long-term adherence to a low FODMAP diet need to be conducted.

Facilitated versus self-guided training of non-ophthalmologists for grading pre-plus and plus disease using fundus images for retinopathy of prematurity screening

PubMed Central

Raufi, Nikolas N.; Morris, Caleb K.; Freedman, Sharon F.; Wallace, David K.; Prakalapakorn, S. Grace

2016-01-01

Purpose Retinopathy of prematurity (ROP) is an important cause of preventable blindness; barriers to screening necessitate novel approaches. While trained non-ophthalmologists can accurately grade retinal images for ROP, effective training protocols are not established. This study compares the effectiveness of facilitated versus self-guided training of non-ophthalmologists for grading retinal images for pre-plus or plus disease in ROP. Methods Forty-eight undergraduate and graduate students were trained to grade retinal images for the presence of pre-plus or plus disease. Students were randomly assigned to one of two training protocols. Both utilized identical electronic slideshows; one guided by an in-person facilitator, and the other was self-guided. After completing their respective training, students proficient in grading pre-plus and plus disease graded images in a telemedicine screening scenario. Accuracy of grading was compared to the reference standard of clinical examination. Results 83% (40/48) of trained students (91% in the facilitated vs. 77% in the self-guided group, p=0.26) were proficient and qualified to grade the ROP telemedicine screening scenario. Median accuracy for grading normal, pre-plus or plus disease was 69% (70% in the facilitated vs. 68% in the self-guided group, p=0.91). When considering the designation of pre-plus or plus disease by graders as a screening test for detecting plus disease (confirmed on clinical exam), the median sensitivity and specificity of all students was 95% and 64%, respectively. Conclusions Both facilitated- and self-guided teaching protocols yielded similar performance in ROP image grading for pre-plus or plus disease. Self-guided training protocols may be adequate to train non-ophthalmologists to grade retinal images for pre-plus and plus disease with high sensitivity. PMID:27224953

On the generation of log-Lévy distributions and extreme randomness

NASA Astrophysics Data System (ADS)

Eliazar, Iddo; Klafter, Joseph

2011-10-01

The log-normal distribution is prevalent across the sciences, as it emerges from the combination of multiplicative processes and the central limit theorem (CLT). The CLT, beyond yielding the normal distribution, also yields the class of Lévy distributions. The log-Lévy distributions are the Lévy counterparts of the log-normal distribution, they appear in the context of ultraslow diffusion processes, and they are categorized by Mandelbrot as belonging to the class of extreme randomness. In this paper, we present a natural stochastic growth model from which both the log-normal distribution and the log-Lévy distributions emerge universally—the former in the case of deterministic underlying setting, and the latter in the case of stochastic underlying setting. In particular, we establish a stochastic growth model which universally generates Mandelbrot’s extreme randomness.

Association between non-steroidal anti-inflammatory drug use and melanoma risk: a meta-analysis of 13 studies.

PubMed

Li, Shan; Liu, Yanqiong; Zeng, Zhiyu; Peng, Qiliu; Li, Ruolin; Xie, Li; Qin, Xue; Zhao, Jinmin

2013-08-01

Results of the association between non-steroidal anti-inflammatory drugs (NSAIDs) and melanoma risk have been inconsistent. We performed a meta-analysis of relevant studies to investigate the hypothesis of an association between NSAID use and melanoma risk. Systematic searches of the PubMed and several other databases up to 23 March 2013 were retrieved. All epidemiologic studies regarding NSAIDs and melanoma risk were included. Fixed- or random-effects meta-analytical models were used to calculate relative risk (RR) and corresponding 95 % confidence intervals (CIs). Sensitivity analyses, Galbraith plots, and subgroup analyses were also performed. Six case-control studies including 93,432 melanoma cases and 401,251 controls, six cohort studies consisting of 563,380 subjects, and one randomized controlled trial encompassing 39,876 participants were included in this analysis. Compared to non-use, ever use of any NSAIDs was not statistically significantly associated with melanoma risk based on the random-effects models (RR = 0.97, 95 % CI = 0.90-10.4, p = 0.401). No differences were found in the effects on melanoma risk of aspirin, non-aspirin NSAIDs, and cyclooxygenase-2 inhibitor use overall and stratified by gender. However, a slight reduction in the risk of melanoma by taking aspirin was observed in case-control studies (RR = 0.88, 95 % CI = 0.80-0.96, p = 0.004). Findings from this pooled analysis do not support the hypothesis that NSAID use provides potential benefits in preventing melanoma. More and larger randomized trials, including adequate numbers of patients, are required to further evaluate the relationship between NSAID use and melanoma.

Analysis of energy expenditure in diet-induced obese rats

PubMed Central

Assaad, Houssein; Yao, Kang; Tekwe, Carmen D.; Feng, Shuo; Bazer, Fuller W.; Zhou, Lan; Carroll, Raymond J.; Meininger, Cynthia J.; Wu, Guoyao

2014-01-01

Development of obesity in animals is affected by energy intake, dietary composition, and metabolism. Useful models for studying this metabolic problem are Sprague-Dawley rats fed low-fat (LF) or high-fat (HF) diets beginning at 28 days of age. Through experimental design, their dietary intakes of energy, protein, vitamins, and minerals per kg body weight (BW) do not differ in order to eliminate confounding factors in data interpretation. The 24-h energy expenditure of rats is measured using indirect calorimetry. A regression model is constructed to accurately predict BW gain based on diet, initial BW gain, and the principal component scores of respiratory quotient and heat production. Time-course data on metabolism (including energy expenditure) are analyzed using a mixed effect model that fits both fixed and random effects. Cluster analysis is employed to classify rats as normal-weight or obese. HF-fed rats are heavier than LF-fed rats, but rates of their heat production per kg non-fat mass do not differ. We conclude that metabolic conversion of dietary lipids into body fat primarily contributes to obesity in HF-fed rats. PMID:24896330

The relaxation response: reducing stress and improving cognition in healthy aging adults.

PubMed

Galvin, Jennifer A; Benson, Herbert; Deckro, Gloria R; Fricchione, Gregory L; Dusek, Jeffery A

2006-08-01

Aging adults are vulnerable to the effects of a negative emotional state. The relaxation response (RR) is a mind-body intervention that counteracts the harmful effects of stress. Previous studies with relaxation techniques have shown the non-pharmacological benefit of reducing stress and improving the memory of healthy older adults. Our pilot study evaluated whether a RR training program would decrease anxiety levels, improve attention, declarative memory performance and/or decrease salivary cortisol levels in healthy older adults. Fifteen adults participated and were randomly assigned to a RR training or control groups. Mean age was 71.3 years and mean education level was 17.9 years. Reaction time on a simple attention/psychomotor task was significantly improved (p<0.0025) with RR training, whereas there was no significant improvement on complex tasks of attention, verbal, or visual declarative memory tests. Self-reported state anxiety levels showed a marginally significant reduction (p<0.066). All subjects' salivary cortisol levels were within low-normal range and did not significantly change. Our 5-week program in highly educated, mobile, healthy, aging adults significantly improved performance on a simple attention task.

Effective non-pharmacological birth interventions.

PubMed

Davis, Jude

2015-02-01

Midwifery expertise is in 'normal' birth. What constitutes 'normal' is debatable, but well embedded within 'normal' are the birth plans of women who aspire to give birth without using drugs. To give birth without drugs for many may seem undesirable or intolerable, especially to those whose cultural references to birth have been overwhelmingly negative, fearful or risk-obsessed. However, significant numbers of women have confidence in their innate ability to birth their babies and are rightfully concerned about the undesirable side effects of pharmacological interventions. As well as providing wider choice for women, looking for alternative ways of addressing pain and progress in labour enhances birth attendants' knowledge and becomes a delightful journey of discovering the ancient and modern arts of midwifery. Shared here are a collection of ideas to contribute to the toolkit of knowledge about non-pharmacological interventions.

Subacute effects of cervicothoracic spinal thrust/non-thrust in addition to shoulder manual therapy plus exercise intervention in individuals with subacromial impingement syndrome: a prospective, randomized controlled clinical trial pilot study.

PubMed

Wright, Alexis A; Donaldson, Megan; Wassinger, Craig A; Emerson-Kavchak, Alicia J

2017-09-01

To determine the subacute effects of cervicothoracic spinal thrust/non-thrust in addition to shoulder non-thrust plus exercise in patients with subacromial pathology. This was a randomized, single blinded controlled trial pilot study. This trial was registered at ClinicalTrials.gov (NCT01753271) and reported according to Consolidated Standards of Reporting Trials requirements. Patients were randomly assigned to either shoulder treatment plus cervicothoracic spinal thrust/non-thrust or shoulder treatment-only group. Primary outcomes were average pain intensity (Numeric Pain Rating Scale) and physical function (Shoulder Pain and Disability Index) at 2 weeks, 4 weeks, and patient discharge. 18 patients, mean age 43.1(15.8) years satisfied the eligibility criteria and were analyzed for follow-up data. Both groups showed statistically significant improvements in both pain and function at 2 weeks, 4 weeks, and discharge. The between-group differences for changes in pain or physical function were not significant at any time point. The addition of cervicothoracic spinal thrust/non-thrust to the shoulder treatment-only group did not significantly alter improvement in pain or function in patients with subacromial pathology. Both approaches appeared to provide an equally notable benefit. Both groups improved on all outcomes and met the criteria for clinical relevance for both pain and function. 2b.

Comparison of Mixing Calculations for Reacting and Non-Reacting Flows in a Cylindrical Duct

NASA Technical Reports Server (NTRS)

Oechsle, V. L.; Mongia, H. C.; Holdeman, J. D.

1994-01-01

A production 3-D elliptic flow code has been used to calculate non-reacting and reacting flow fields in an experimental mixing section relevant to a rich burn/quick mix/lean burn (RQL) combustion system. A number of test cases have been run to assess the effects of the variation in the number of orifices, mass flow ratio, and rich-zone equivalence ratio on the flow field and mixing rates. The calculated normalized temperature profiles for the non-reacting flow field agree qualitatively well with the normalized conserved variable isopleths for the reacting flow field indicating that non-reacting mixing experiments are appropriate for screening and ranking potential rapid mixing concepts. For a given set of jet momentum-flux ratio, mass flow ratio, and density ratio (J, MR, and DR), the reacting flow calculations show a reduced level of mixing compared to the non-reacting cases. In addition, the rich-zone equivalence ratio has noticeable effect on the mixing flow characteristics for reacting flows.

Neutron monitor generated data distributions in quantum variational Monte Carlo

NASA Astrophysics Data System (ADS)

Kussainov, A. S.; Pya, N.

2016-08-01

We have assessed the potential applications of the neutron monitor hardware as random number generator for normal and uniform distributions. The data tables from the acquisition channels with no extreme changes in the signal level were chosen as the retrospective model. The stochastic component was extracted by fitting the raw data with splines and then subtracting the fit. Scaling the extracted data to zero mean and variance of one is sufficient to obtain a stable standard normal random variate. Distributions under consideration pass all available normality tests. Inverse transform sampling is suggested to use as a source of the uniform random numbers. Variational Monte Carlo method for quantum harmonic oscillator was used to test the quality of our random numbers. If the data delivery rate is of importance and the conventional one minute resolution neutron count is insufficient, we could always settle for an efficient seed generator to feed into the faster algorithmic random number generator or create a buffer.

Implantation in assisted reproduction: a look at endometrial receptivity.

PubMed

Fatemi, H M; Popovic-Todorovic, B

2013-11-01

Implantation failure in assisted reproduction is thought to be mainly due to impaired uterine receptivity. With normal uterine anatomy, changes in endocrine profile during ovarian stimulation and medical conditions of the mother (i.e. thrombophilia and abnormal immunological response) could result in a non-receptive endometrium. High oestradiol concentrations during ovarian stimulation lead to premature progesterone elevation, causing endometrial advancement and hampering implantation, which can be overcome by a freeze-all approach and embryo transfer in natural cycles or by milder stimulation protocols. Patients with recurrent implantation failure (RIF) should be tested for inherited and acquired thrombophilias. Each patient should be individually assessed and counselled regarding therapy with low-molecular-weight heparin (LMWH). Empirical treatment with LMWH, aspirin or corticosteroids is not effective for women with RIF who have negative thrombophilic tests. If thrombophilic tests are normal, patients should be tested for immunological causes. If human leukocyte antigen dissimilarity is proven, treatment with intravenous immunoglobulin might be beneficial. Preliminary observational studies using intralipid infusion in the presence of increased natural killer cytotoxic activity are interesting but the proposed rationale is controversial and randomized controlled trials are needed. Hysteroscopy and/or endometrial scratching in the cycle preceding ovarian stimulation should become standard for patients with RIF. Copyright © 2013 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

Weibull mixture regression for marginal inference in zero-heavy continuous outcomes.

PubMed

Gebregziabher, Mulugeta; Voronca, Delia; Teklehaimanot, Abeba; Santa Ana, Elizabeth J

2017-06-01

Continuous outcomes with preponderance of zero values are ubiquitous in data that arise from biomedical studies, for example studies of addictive disorders. This is known to lead to violation of standard assumptions in parametric inference and enhances the risk of misleading conclusions unless managed properly. Two-part models are commonly used to deal with this problem. However, standard two-part models have limitations with respect to obtaining parameter estimates that have marginal interpretation of covariate effects which are important in many biomedical applications. Recently marginalized two-part models are proposed but their development is limited to log-normal and log-skew-normal distributions. Thus, in this paper, we propose a finite mixture approach, with Weibull mixture regression as a special case, to deal with the problem. We use extensive simulation study to assess the performance of the proposed model in finite samples and to make comparisons with other family of models via statistical information and mean squared error criteria. We demonstrate its application on real data from a randomized controlled trial of addictive disorders. Our results show that a two-component Weibull mixture model is preferred for modeling zero-heavy continuous data when the non-zero part are simulated from Weibull or similar distributions such as Gamma or truncated Gauss.

Quantiles for Finite Mixtures of Normal Distributions

ERIC Educational Resources Information Center

Rahman, Mezbahur; Rahman, Rumanur; Pearson, Larry M.

2006-01-01

Quantiles for finite mixtures of normal distributions are computed. The difference between a linear combination of independent normal random variables and a linear combination of independent normal densities is emphasized. (Contains 3 tables and 1 figure.)

Cerebrospinal Fluid Biomarkers and Reserve Variables as Predictors of Future “Non-Cognitive” Outcomes of Alzheimer’s Disease

PubMed Central

Ingber, Adam P.; Hassenstab, Jason; Fagan, Anne M.; Benzinger, Tammie L.S.; Grant, Elizabeth A.; Holtzman, David M.; Morris, John C.; Roe, Catherine M.

2016-01-01

Background The influence of reserve variables and Alzheimer’s disease (AD) biomarkers on cognitive test performance has been fairly well-characterized. However, less is known about the influence of these factors on “non-cognitive” outcomes, including functional abilities and mood. Objective We examined whether cognitive and brain reserve variables mediate how AD biomarker levels in cognitively normal persons predict future changes in function, mood, and neuropsychiatric behavior. Methods Non-cognitive outcomes were examined in 328 individuals 50 years and older enrolled in ongoing studies of aging and dementia at the Knight Alzheimer Disease Research Center (ADRC). All participants were cognitively normal at baseline (Clinical Dementia Rating [CDR] 0), completed cerebrospinal fluid (CSF) and structural neuroimaging studies within one year of baseline, and were followed for an average of 4.6 annual visits. Linear mixed effects models explored how cognitive reserve and brain reserve variables mediate the relationships between AD biomarker levels and changes in function, mood, and neuropsychiatric behavior in cognitively normal participants. Results Education levels did not have a significant effect on predicting non-cognitive decline. However, participants with smaller brain volumes exhibited the worst outcomes on measures of mood, functional abilities, and behavioral disturbance. This effect was most pronounced in individuals who also had abnormal CSF biomarkers. Conclusions The findings suggest that brain reserve plays a stronger, or earlier, role than cognitive reserve in protecting against non-cognitive impairment in AD. PMID:27104893

Stress management and dietary counseling in hypertensive patients: a pilot study of additional effect.

PubMed

Katsarou, Alexia L; Vryonis, Marios M; Protogerou, Athanassios D; Alexopoulos, Evangelos C; Achimastos, Apostolos; Papadogiannis, Dimitrios; Chrousos, George P; Darviri, Christina

2014-01-01

In Western societies, cardiovascular (CV) disease is the primary cause of mortality, and high blood pressure (BP) is the main reversible factor leading to CV disease. Dietary habits and psychosocial stress contribute to the establishment of hypertension, while its role in the control of high BP is currently examined. In this study, we examined the effect and feasibility of a combined intervention of dietary education and stress management on the control of hypertension. A randomized, controlled pilot study was designed to evaluate the effect of combined education on stress management techniques and dietary habits (Mediterranean diet principle) on office BP after eight weeks. Of the 45 randomized subjects, 36 were included in the final analysis (control group = 20 (age: 67 ± 12 years, 31.8%, males) and intervention group = 16 (age: 62 ± 12 years, 47%, males)). CV disease risk factors (except smoking), BP, dietary habits, perceived stress and physical activity (all assessed with validated questionnaires) were similar between the two groups at baseline. After eight weeks, office BP (systolic and diastolic) and perceived stress were significantly reduced, whereas the adherence in Mediterranean diet principle was significantly increased, but only in the intervention group. A combined intervention of stress management techniques and Mediterranean diet education seems to be beneficial for BP reduction. Such interventions could possibly serve as a complementary treatment along with drug therapy or in the early treatment of high normal BP. A call to action for designing epidemiological studies and evaluating the efficacy of such non-pharmacological treatment strategies is therefore warranted.

Estimation of treatment effects in all-comers randomized clinical trials with a predictive marker.

PubMed

Choai, Yuki; Matsui, Shigeyuki

2015-03-01

Recent advances in genomics and biotechnologies have accelerated the development of molecularly targeted treatments and accompanying markers to predict treatment responsiveness. However, it is common at the initiation of a definitive phase III clinical trial that there is no compelling biological basis or early trial data for a candidate marker regarding its capability in predicting treatment effects. In this case, it is reasonable to include all patients as eligible for randomization, but to plan for prospective subgroup analysis based on the marker. One analysis plan in such all-comers designs is the so-called fallback approach that first tests for overall treatment efficacy and then proceeds to testing in a biomarker-positive subgroup if the first test is not significant. In this approach, owing to the adaptive nature of the analysis and a correlation between the two tests, a bias will arise in estimating the treatment effect in the biomarker-positive subgroup after a non-significant first overall test. In this article, we formulate the bias function and show a difficulty in obtaining unbiased estimators for a whole range of an associated parameter. To address this issue, we propose bias-corrected estimation methods, including those based on an approximation of the bias function under a bounded range of the parameter using polynomials. We also provide an interval estimation method based on a bivariate doubly truncated normal distribution. Simulation experiments demonstrated a success in bias reduction. Application to a phase III trial for lung cancer is provided. © 2014, The International Biometric Society.

Run charts revisited: a simulation study of run chart rules for detection of non-random variation in health care processes.

PubMed

Anhøj, Jacob; Olesen, Anne Vingaard

2014-01-01

A run chart is a line graph of a measure plotted over time with the median as a horizontal line. The main purpose of the run chart is to identify process improvement or degradation, which may be detected by statistical tests for non-random patterns in the data sequence. We studied the sensitivity to shifts and linear drifts in simulated processes using the shift, crossings and trend rules for detecting non-random variation in run charts. The shift and crossings rules are effective in detecting shifts and drifts in process centre over time while keeping the false signal rate constant around 5% and independent of the number of data points in the chart. The trend rule is virtually useless for detection of linear drift over time, the purpose it was intended for.

Randomized controlled trial of a treatment for anorexia and bulimia nervosa

PubMed Central

Bergh, Cecilia; Brodin, Ulf; Lindberg, Greger; Södersten, Per

2002-01-01

Evidence for the effectiveness of existing treatments of patients with eating disorders is weak. Here we describe and evaluate a method of treatment in a randomized controlled trial. Sixteen patients, randomly selected out of a group composed of 19 patients with anorexia nervosa and 13 with bulimia nervosa, were trained to eat and recognize satiety by using computer support. They rested in a warm room after eating, and their physical activity was restricted. The patients in the control group (n = 16) received no treatment. Remission was defined by normal body weight (anorexia), cessation of binge eating and purging (bulimia), a normal psychiatric profile, normal laboratory test values, normal eating behavior, and resumption of social activities. Fourteen patients went into remission after a median of 14.4 months (range 4.9–26.5) of treatment, but only one patient went into remission while waiting for treatment (P = 0.0057). Relapse is considered a major problem in patients who have been treated to remission. We therefore report results on a total of 168 patients who have entered our treatment program. The estimated rate of remission was 75%, and estimated time to remission was 14.7 months (quartile range 9.6 ≥ 32). Six patients (7%) of 83 who were treated to remission relapsed, but the others (93%) have remained in remission for 12 months (quartile range 6–36). Because the risk of relapse is maximal in the first year after remission, we suggest that most patients treated with this method recover. PMID:12082182

Relationships between nonlinear normal modes and response to random inputs

NASA Astrophysics Data System (ADS)

Schoneman, Joseph D.; Allen, Matthew S.; Kuether, Robert J.

2017-02-01

The ability to model nonlinear structures subject to random excitation is of key importance in designing hypersonic aircraft and other advanced aerospace vehicles. When a structure is linear, superposition can be used to construct its response to a known spectrum in terms of its linear modes. Superposition does not hold for a nonlinear system, but several works have shown that a system's dynamics can still be understood qualitatively in terms of its nonlinear normal modes (NNMs). This work investigates the connection between a structure's undamped nonlinear normal modes and the spectrum of its response to high amplitude random forcing. Two examples are investigated: a spring-mass system and a clamped-clamped beam modeled within a geometrically nonlinear finite element package. In both cases, an intimate connection is observed between the smeared peaks in the response spectrum and the frequency-energy dependence of the nonlinear normal modes. In order to understand the role of coupling between the underlying linear modes, reduced order models with and without modal coupling terms are used to separate the effect of each NNM's backbone from the nonlinear couplings that give rise to internal resonances. In the cases shown here, uncoupled, single-degree-of-freedom nonlinear models are found to predict major features in the response with reasonable accuracy; a highly inexpensive approximation such as this could be useful in design and optimization studies. More importantly, the results show that a reduced order model can be expected to give accurate results only if it is also capable of accurately predicting the frequency-energy dependence of the nonlinear modes that are excited.

Effect of soy protein supplementation in patients with chronic hepatitis C: A randomized clinical trial

PubMed Central

Oliveira, Lucivalda PM; de Jesus, Rosangela P; Boulhosa, Ramona SSB; Mendes, Carlos Mauricio C; Gnoatto, Maria Cecilia; Lemaire, Denise C; Toralles, Maria Betania P; Cavalcante, Lourianne N; Lyra, Andre C; Lyra, Luiz GC

2012-01-01

AIM: To evaluate the effects of soy supplementation on insulin resistance, fatty liver and alanine aminotransferase (ALT) levels in non-diabetic patients with chronic hepatitis C (CHC). METHODS: In a prospective, randomized and single-blinded clinical trial, we compared patients with CHC who had casein as a supplement (n = 80) (control group), with patients who consumed a soy supplement diet (n = 80) [intervention group (IG)]. Both groups received 32 g/d of protein for 12 wk. RESULTS: Patients’ baseline features showed that 48.1% were overweight, 43.7% had abdominal fat accumulation, 34.7% had hepatic steatosis and 36.3% had an homeostasis model assessment index of insulin resistance (HOMA-IR) ≥ 3.0. Descriptive analysis showed that protein supplementation diet reduced hepatic steatosis in both groups; however, significant reductions in ALT levels occurred in the soy group. Multiple regression modeling indicated that in the presence of severe fibrosis (F3/F4), γ glutamyl transferase elevation and high density lipoprotein (HDL) reduction, the intervention group had 75% less chance of developing hepatic steatosis (OR= 0.25; 95% CI: 0.06-0.82) and 55% less chance of presenting with an ALT level ≥ 1.5 × the upper limit of normal (ULN) (OR = 0.45, 95% CI: 0.22-0.89). Soy treatment did not have any effect on insulin resistance (OR = 1.92; 95% CI: 0.80-4.83), which might be attributed to the fact that the HOMA-IR values at baseline in most of our patients were in the normal range. Advanced hepatic fibrosis, an ALT level > 1.5 × ULN and visceral fat were predictors of an HOMA-IR ≥ 3. The IG group had a reduced risk of an ALT level > 1.5 × ULN. An HOMA-IR ≥ 3.0 and HDL < 35 mg/dL were also risk factors for increased ALT. CONCLUSION: Soy supplementation decreased ALT levels and thus may improve liver inflammation in hepatitis C virus (HCV) patients; it also reduced hepatic steatosis in a subgroup of patients but did not change insulin resistance. It should be considered in the nutritional care of HCV patients. PMID:22611313

A quality control method for intensity-modulated radiation therapy planning based on generalized equivalent uniform dose.

PubMed

Pang, Haowen; Sun, Xiaoyang; Yang, Bo; Wu, Jingbo

2018-05-01

To ensure good quality intensity-modulated radiation therapy (IMRT) planning, we proposed the use of a quality control method based on generalized equivalent uniform dose (gEUD) that predicts absorbed radiation doses in organs at risk (OAR). We conducted a retrospective analysis of patients who underwent IMRT for the treatment of cervical carcinoma, nasopharyngeal carcinoma (NPC), or non-small cell lung cancer (NSCLC). IMRT plans were randomly divided into data acquisition and data verification groups. OAR in the data acquisition group for cervical carcinoma and NPC were further classified as sub-organs at risk (sOAR). The normalized volume of sOAR and normalized gEUD (a = 1) were analyzed using multiple linear regression to establish a fitting formula. For NSCLC, the normalized intersection volume of the planning target volume (PTV) and lung, the maximum diameter of the PTV (left-right, anterior-posterior, and superior-inferior), and the normalized gEUD (a = 1) were analyzed using multiple linear regression to establish a fitting formula for the lung gEUD (a = 1). The r-squared and P values indicated that the fitting formula was a good fit. In the data verification group, IMRT plans verified the accuracy of the fitting formula, and compared the gEUD (a = 1) for each OAR between the subjective method and the gEUD-based method. In conclusion, the gEUD-based method can be used effectively for quality control and can reduce the influence of subjective factors on IMRT planning optimization. © 2018 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.

Evaluation of posture and pain in persons with benign joint hypermobility syndrome.

PubMed

Booshanam, Divya S; Cherian, Binu; Joseph, Charles Premkumar A R; Mathew, John; Thomas, Raji

2011-12-01

The objective of the present study is to compare and quantify the postural differences and joint pain distribution between subjects with benign joint hypermobility syndrome (BJHS) and the normal population. This observational, non-randomized, and controlled study was conducted at Rheumatology and Physical Medicine and Rehabilitation Medicine Departments of a tertiary care teaching hospital. Subjects comprise 35 persons with diagnosis of BJHS, and the control group was matched for age and sex. Reedco's Posture score (RPS) and visual analogue scale (VAS) were the outcome measures. The subjects were assessed for pain in ten major joints and rated on a VAS. A standard posture assessment was conducted using the Reedco's Posture score. The same procedure was executed for an age- and sex-matched control group. Mean RPS for the BJHS group was 55.29 ± 8.15 and for the normal group it was 67 ± 11.94. The most common postural deviances in subjects with BJHS were identified in the following areas of head, hip (Sagittal plane), upper back, trunk, and lower back (Coronal plane). Intensity of pain was found to be more in BJHS persons than that of the normal persons, and the knee joints were the most affected. The present study compared and quantified the postural abnormalities and the pain in BJHS persons. The need for postural re-education and specific assessment and training for the most affected joints are discussed. There is a significant difference in posture between subjects with BJHS and the normal population. BJHS persons need special attention to their posture re-education during physiotherapy sessions to reduce long-term detrimental effects on the musculoskeletal system.

Elastic Instability of Slender Rods in Steady Shear Flow Yields Positive First Normal Stress Differences

NASA Astrophysics Data System (ADS)

Becker, Leif E.; Shelley, Michael J.

2000-11-01

First normal stress differences in shear flow are a fundamental property of Non-Newtonian fluids. Experiments involving dilute suspensions of slender fibers exhibit a sharp transition to non-zero normal stress differences beyond a critical shear rate, but existing continuum theories for rigid rods predict neither this transition nor the corresponding magnitude of this effect. We present the first conclusive evidence that elastic instabilities are predominantly responsible for observed deviations from the dilute suspension theory of rigid rods. Our analysis is based on slender body theory and the equilibrium equations of elastica. A straight slender body executing its Jeffery orbit in Couette flow is subject to axial fluid forcing, alternating between compression and tension. We present a stability analysis showing that elastic instabilities are possible for strong flows. Simulations give the fully non-linear evolution of this shape instability, and show that flexibility of the fibers alone is sufficient to cause both shear-thinning and significant first normal stress differences.

efficacy of dry extract of ivy leaves in the treatment of productive cough.

PubMed

Schönknecht, Karina; Fal, Andrzej M; Mastalerz-Migas, Agnieszka; Joachimiak, Monika; Doniec, Zbigniew

Introduction: Coughing is a physiological, spontaneous defense mechanism against irritants that stimulate respiratory mucosa. Productive cough should be not suppressed; instead, mucus-dissolving agents are recommended. One of the expectorants, which increases the excretion volume, is the herbal medicine derived from ivy leaves. The ivy extract contains triterpene saponins, which have secretory properties. The aim of this study was to determine the effectiveness and safety of the treatment with the medicinal product Hedussin®, containing dry ivy extract, in the therapy of productive cough in the course of the respiratory tract infection. Material and methods:This was a non-randomized, non-interventional, multicenter, open-label, post-authorization effectiveness study (PAES). The study group consisted of 464 patients aged 2-12 years with productive cough. The study was supported by a questionnaire that included: the type of cough etiological factor, Bronchitis Severity Score (BSS), temperature, and prescription of antibiotic therapy. Effectiveness and safety of the therapy with Hedussin® was assessed at the follow-up visit. Results and conclusion: Improvement in cough was reported in 93.3% subjects; improvement in chest pain on coughing was reported in 84.7%, in wheezing - in 90.0%, in dyspnoea - in 88.7%, and in auscultation changes - in 94.8%. In addition, decline or normalization of body temperature was found in 96.0% of subjects. No adverse drug reactions were reported in the study population. The non-antibiotic treated group showed similar proportions. The results of this study support the efficacy of Hedussin® prescribed for the treatment of productive cough in the course of respiratory tract infections. Hedussin® was well tolerated by sick children aged 2-12 years.

Effects of intermode nonlinearity and intramode nonlinearity on modulation instability in randomly birefringent two-mode optical fibers

NASA Astrophysics Data System (ADS)

Li, Jin Hua; Xu, Hui; Sun, Ting Ting; Pei, Shi Xin; Ren, Hai Dong

2018-05-01

We analyze in detail the effects of the intermode nonlinearity (IEMN) and intramode nonlinearity (IRMN) on modulation instability (MI) in randomly birefringent two-mode optical fibers (RB-TMFs). In the anomalous dispersion regime, the MI gain enhances significantly as the IEMN and IRMN coefficients increases. In the normal dispersion regime, MI can be generated without the differential mode group delay (DMGD) effect, as long as the IEMN coefficient between two distinct modes is above a critical value, or the IRMN coefficient inside a mode is below a critical value. This critical IEMN (IRMN) coefficient depends strongly on the given IRMN (IEMN) coefficient and DMGD for a given nonlinear RB-TMF structure, and is independent on the input total power, the power ratio distribution and the group velocity dispersion (GVD) ratio between the two modes. On the other hand, in contrast to the MI band arising from the pure effect of DMGD in the normal dispersion regime, where MI vanishes after a critical total power, the generated MI band under the combined effects of IEMN and IRMN without DMGD exists for any total power and enhances with the total power. The MI analysis is verified numerically by launching perturbed continuous waves (CWs) with wave propagation method.

Effect of Metal Artifacts on Detection of Vertical Root Fractures Using Two Cone Beam Computed Tomography Systems.

PubMed

Safi, Yaser; Aghdasi, Mohammad Mehdi; Ezoddini-Ardakani, Fatemeh; Beiraghi, Samira; Vasegh, Zahra

2015-01-01

Vertical root fracture (VRF) is common in endodontically treated teeth. Conventional and digital radiographies have limitations for detection of VRFs. Cone-beam computed tomography (CBCT) offers greater detection accuracy of VRFs in comparison with conventional radiography. This study compared the effects of metal artifacts on detection of VRFs by using two CBCT systems. Eighty extracted premolars were selected and sectioned at the level of the cemento enamel junction (CEJ). After preparation, root canals were filled with gutta-percha. Subsequently, two thirds of the root fillings were removed for post space preparation and a custom-made post was cemented into each canal. The teeth were randomly divided into two groups (n=40). In the test group, root fracture was created with Instron universal testing machine. The control teeth remained intact. CBCT scans of all teeth were obtained with either New Tom VGI or Soredex Scanora 3D. Three observers analyzed the images for detection of VRF. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for VRF detection and percentage of probable cases were calculated for each imaging system and compared using non-parametric tests considering the non-normal distribution of data. The inter-observer reproducibility was calculated using the weighted kappa coefficient. There were no statistically significant differences in sensitivity, specificity, PPV and NPV between the two CBCT systems. The effect of metal artifacts on VRF detection was not significantly different between the two CBCT systems.

Theory of Mind training in children with autism: a randomized controlled trial.

PubMed

Begeer, Sander; Gevers, Carolien; Clifford, Pamela; Verhoeve, Manja; Kat, Kirstin; Hoddenbach, Elske; Boer, Frits

2011-08-01

Many children with Autism Spectrum Disorders (ASD) participate in social skills or Theory of Mind (ToM) treatments. However, few studies have shown evidence for their effectiveness. The current study used a randomized controlled design to test the effectiveness of a 16-week ToM treatment in 8-13 year old children with ASD and normal IQs (n = 40). The results showed that, compared to controls, the treated children with ASD improved in their conceptual ToM skills, but their elementary understanding, self reported empathic skills or parent reported social behaviour did not improve. Despite the effects on conceptual understanding, the current study does not indicate strong evidence for the effectiveness of a ToM treatment on the daily life mindreading skills.

The inhibitory effect of black soybean on hepatic cholesterol accumulation in high cholesterol and high fat diet-induced non-alcoholic fatty liver disease.

PubMed

Jung, Ji-Hye; Kim, Hyun-Sook

2013-10-01

Non-alcoholic fatty liver disease (NAFLD) is defined as excess of fat in the liver. We investigated the effects of black soybean on the cholesterol metabolism and insulin resistance of mice fed high cholesterol/fat diets. Mice were randomly allocated into four groups that were fed different diets: the normal cholesterol/fat diet; high cholesterol/fat diets (HCD); and HCD with 1%, and 4% black soybean powder (1B-HCD, and 4B-HCD). Liver total cholesterol and triglyceride concentrations were significantly lower in the black soybean-supplemented groups than that in the HCD group. PCR revealed significantly lower hepatic SREBP2 and HMG-CoA reductase mRNA levels of black soybean-supplemented mice. Real-time PCR revealed significantly higher hepatic ABCA1 mRNA level of black soybean-supplemented mice, which may increase cholesterol efflux. Liver bile acids concentration was significantly high in the 4B-HCD group. Black soybean stimulated secretion of adiponectin, activation of pAMPK, and eliminated free fatty acids in the liver. Black soybean supplementation decreased MDA and nitrate level. The activities of SOD, catalase, and GPx were restored by black soybean supplementation. Our data strongly indicate that black soybean influences the balance between oxidative and antioxidative stress. We suggest that black soybean improves cholesterol metabolism, insulin resistance, and alleviates oxidative damage in NAFLD. Published by Elsevier Ltd.

Does telemedicine improve treatment outcomes for diabetes? A meta-analysis of results from 55 randomized controlled trials.

PubMed

Su, Dejun; Zhou, Junmin; Kelley, Megan S; Michaud, Tzeyu L; Siahpush, Mohammad; Kim, Jungyoon; Wilson, Fernando; Stimpson, Jim P; Pagán, José A

2016-06-01

To assess the overall effect of telemedicine on diabetes management and to identify features of telemedicine interventions that are associated with better diabetes management outcomes. Hedges's g was estimated as the summary measure of mean difference in HbA1c between patients with diabetes who went through telemedicine care and those who went through conventional, non-telemedicine care using a random-effects model. Q statistics were calculated to assess if the effect of telemedicine on diabetes management differs by types of diabetes, age groups of patients, duration of intervention, and primary telemedicine approaches used. The analysis included 55 randomized controlled trials with a total of 9258 patients with diabetes, out of which 4607 were randomized to telemedicine groups and 4651 to conventional, non-telemedicine care groups. The results favored telemedicine over conventional care (Hedges's g=-0.48, p<0.001) in diabetes management. The beneficial effect of telemedicine were more pronounced among patients with type 2 diabetes (Hedges's g=-0.63, p<0.001) than among those with type 1 diabetes (Hedges's g=-0.27, p=0.027) (Q=4.25, p=0.04). Compared to conventional care, telemedicine is more effective in improving treatment outcomes for diabetes patients, especially for those with type 2 diabetes. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Effects of Teaching Gardening on Science Students' Attitudes toward Entrepreneurial Skills Acquisition in Jos South, Plateau State, Nigeria

ERIC Educational Resources Information Center

Charity, Dimlong; Ozoji, Bernadette Ebele; Osasebor, Florence Osaze; Ibn Umar, Suleiman

2017-01-01

This study investigated the effects of teaching gardening on science students' attitudes toward entrepreneurial skills acquisition in Jos South, Plateau State, Nigeria. The study employed the non-randomized pre-test post-test non-equivalent control group design. A sample of 75 senior secondary school students from two intact classes, randomly…

Effects of a Target-Task Problem-Solving Model on Senior Secondary School Students' Performance in Physics

ERIC Educational Resources Information Center

Olaniyan, A. O.; Omosewo, E. O.

2015-01-01

The study investigated the Effects of a Target-Task Problem-Solving Model on Senior Secondary School Students' Performance in Physics. The research design was a quasi-experimental, non-randomized, non-equivalent pretest, post-test using a control group. The study was conducted in two schools purposively selected and involved a total of 120 Senior…

Pretreatment with remifentanil, fentanyl, or lidocaine to prevent withdrawal after rocuronium using venous occlusion technique in children and adolescents: a prospective randomized placebo-controlled double-blind study.

PubMed

Abu-Halaweh, S A; Aloweidi, A K; Qudaisat, I Y; Al-Hussami, M O; Al Zaben, K R; Abu-Halaweh, A S

2014-12-01

Pain caused by intravenous injection of the muscle relaxant rocuronium bromide is common in children and adolescents. The cause of this unwanted effect is still unclear, and different pretreatment drugs have been administered in attempts to alleviate this side effect, with varying degrees of success. This study used a 60-s venous occlusion technique to evaluate the effectiveness of pretreatment with lidocaine, fentanyl, or remifentanil in preventing pain-induced withdrawal caused by intravenous injection of rocuronium bromide during the induction of general anesthesia. One hundred and one child and adolescent patients, ASA Ι-II, requiring various surgical procedures under general anesthesia with muscle relaxation and mechanical ventilation, were enrolled. Patients were allocated randomly using computer-generated randomization into one of four pretreatment groups: a remifentanil group (1 µg/kg, n = 25), fentanyl group (1 µg/kg, n = 26), lidocaine 1% group (0.5 mg/kg, n = 25), and normal saline group (n = 25). Drug doses were prepared in normal saline to a total volume of 5 ml. Venous occlusion was applied 10 cm above the venous access site. Pretreatment drugs were injected and retained for 60 s at the site of injection by an anesthetist blinded to group allocation. After release of the tourniquet, rocuronium (0.5 mg/kg) was then injected over 5 s, and withdrawal was recorded by another anesthetist blinded to group allocation. Descriptive statistics, analysis of variance, and a chi-squared test were used to statistically analyze the results as appropriate. Compared to normal saline, all other pretreatment groups scored a significantly lower mean of withdrawal response (P < 0.001). Lidocaine was superior to both remifentanil (P < 0.05) and fentanyl (P < 0.05) in suppressing the withdrawal response to rocuronium injection. Remifentanil was superior to fentanyl in suppressing the withdrawal response caused by rocuronium injection (P < 0.001). Using a venous occlusion technique for 60 s, lidocaine was found to be most effective in preventing the withdrawal effect caused by rocuronium injection in children and adolescents. Lidocaine was superior to remifentanil which, in turn, was more effective than fentanyl.

Improved statistical assessment of a long-term groundwater-quality dataset with a non-parametric permutation method

NASA Astrophysics Data System (ADS)

Thomas, M. A.

2016-12-01

The Waste Isolation Pilot Plant (WIPP) is the only deep geological repository for transuranic waste in the United States. As the Science Advisor for the WIPP, Sandia National Laboratories annually evaluates site data against trigger values (TVs), metrics whose violation is indicative of conditions that may impact long-term repository performance. This study focuses on a groundwater-quality dataset used to redesign a TV for the Culebra Dolomite Member (Culebra) of the Permian-age Rustler Formation. Prior to this study, a TV violation occurred if the concentration of a major ion fell outside a range defined as the mean +/- two standard deviations. The ranges were thought to denote conditions that 95% of future values would fall within. Groundwater-quality data used in evaluating compliance, however, are rarely normally distributed. To create a more robust Culebra groundwater-quality TV, this study employed the randomization test, a non-parametric permutation method. Recent groundwater compositions considered TV violations under the original ion concentration ranges are now interpreted as false positives in light of the insignificant p-values calculated with the randomization test. This work highlights that the normality assumption can weaken as the size of a groundwater-quality dataset grows over time. Non-parametric permutation methods are an attractive option because no assumption about the statistical distribution is required and calculating all combinations of the data is an increasingly tractable problem with modern workstations. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000. This research is funded by WIPP programs administered by the Office of Environmental Management (EM) of the U.S. Department of Energy. SAND2016-7306A

The role of random nanostructures for the omnidirectional anti-reflection properties of the glasswing butterfly.

PubMed

Siddique, Radwanul Hasan; Gomard, Guillaume; Hölscher, Hendrik

2015-04-22

The glasswing butterfly (Greta oto) has, as its name suggests, transparent wings with remarkable low haze and reflectance over the whole visible spectral range even for large view angles of 80°. This omnidirectional anti-reflection behaviour is caused by small nanopillars covering the transparent regions of its wings. In difference to other anti-reflection coatings found in nature, these pillars are irregularly arranged and feature a random height and width distribution. Here we simulate the optical properties with the effective medium theory and transfer matrix method and show that the random height distribution of pillars significantly reduces the reflection not only for normal incidence but also for high view angles.

The role of random nanostructures for the omnidirectional anti-reflection properties of the glasswing butterfly

NASA Astrophysics Data System (ADS)

Siddique, Radwanul Hasan; Gomard, Guillaume; Hölscher, Hendrik

2015-04-01

The glasswing butterfly (Greta oto) has, as its name suggests, transparent wings with remarkable low haze and reflectance over the whole visible spectral range even for large view angles of 80°. This omnidirectional anti-reflection behaviour is caused by small nanopillars covering the transparent regions of its wings. In difference to other anti-reflection coatings found in nature, these pillars are irregularly arranged and feature a random height and width distribution. Here we simulate the optical properties with the effective medium theory and transfer matrix method and show that the random height distribution of pillars significantly reduces the reflection not only for normal incidence but also for high view angles.

Analysis of stationary and dynamic factors affecting highway accident occurrence: A dynamic correlated grouped random parameters binary logit approach.

PubMed

Fountas, Grigorios; Sarwar, Md Tawfiq; Anastasopoulos, Panagiotis Ch; Blatt, Alan; Majka, Kevin

2018-04-01

Traditional accident analysis typically explores non-time-varying (stationary) factors that affect accident occurrence on roadway segments. However, the impact of time-varying (dynamic) factors is not thoroughly investigated. This paper seeks to simultaneously identify pre-crash stationary and dynamic factors of accident occurrence, while accounting for unobserved heterogeneity. Using highly disaggregate information for the potential dynamic factors, and aggregate data for the traditional stationary elements, a dynamic binary random parameters (mixed) logit framework is employed. With this approach, the dynamic nature of weather-related, and driving- and pavement-condition information is jointly investigated with traditional roadway geometric and traffic characteristics. To additionally account for the combined effect of the dynamic and stationary factors on the accident occurrence, the developed random parameters logit framework allows for possible correlations among the random parameters. The analysis is based on crash and non-crash observations between 2011 and 2013, drawn from urban and rural highway segments in the state of Washington. The findings show that the proposed methodological framework can account for both stationary and dynamic factors affecting accident occurrence probabilities, for panel effects, for unobserved heterogeneity through the use of random parameters, and for possible correlation among the latter. The comparative evaluation among the correlated grouped random parameters, the uncorrelated random parameters logit models, and their fixed parameters logit counterpart, demonstrate the potential of the random parameters modeling, in general, and the benefits of the correlated grouped random parameters approach, specifically, in terms of statistical fit and explanatory power. Published by Elsevier Ltd.

Oral supplement enriched in HMB combined with pulmonary rehabilitation improves body composition and health related quality of life in patients with bronchiectasis (Prospective, Randomised Study).

PubMed

Olveira, Gabriel; Olveira, Casilda; Doña, Esperanza; Palenque, Francisco Javier; Porras, Nuria; Dorado, Antonio; Godoy, Ana M; Rubio-Martínez, Elehazara; Rojo-Martínez, Gemma; Martín-Valero, Rocío

2016-10-01

Pulmonary Rehabilitation (PR) is recommended for bronchiectasis but there is no data about its effect on body composition. The aim of this study is to assess the effect of Pulmonary Rehabilitation (PR) for 12 weeks in normally-nourished non-cystic-fibrosis bronchiectasis patients compared with the effect of PR plus a hyperproteic oral nutritional supplement enriched with beta-hydroxy-beta-methylbutyrate (HMB) on body composition, muscle strength, quality of life and serum biomarkers. single center randomized controlled trial, parallel treatment design: Participants were randomly assigned to receive PR for 12 weeks or PR plus ONS (PRONS) (one can per day). Outcome assessments were performed at baseline, 12 weeks and 24 weeks: body composition (Dual-energy X-Ray Absorptiometry (DEXA), mid-arm muscle circumference (MAMC), phase angle by Bio-impedance), health related quality of life (Spanish QOL-B-V3.0, Physical Functioning Scale), handgrip strength, diet questionnaire, and plasma levels of prealbumin, myostatin and somatomedin-c. Thirty patients were randomized (15 per group) without differences in clinical and respiratory variables. In the PRONS group bone mineral density (BMD), mean and maximum handgrip dynamometry, MAMC, QOLB and prealbumin were significantly increased from baseline at 12 and 24 weeks and Fat free Mass (FFM) and FFM index, at 12 weeks. In the PR group only mean handgrip dynamometry and prealbumin were significantly increased at 12 and 24 weeks. In both groups plasma myostatin was reduced at 12 weeks (without significant differences). The addition of a hyperproteic ONS enriched with HMB to Pulmonary Rehabilitation could improve body composition, BMD, muscle strength and health related quality of life in bronchiectasis patients. Clinical Trials Number NCT02048397. Copyright © 2015 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

The clinical examination of non-word repetition tasks in identifying Persian-speaking children with primary language impairment.

PubMed

Kazemi, Yalda; Saeednia, Soodeh

2017-02-01

This study aimed to examine the diagnostic accuracy of a non-word repetition (NWR) test in identifying Persian-speaking preschool children with specific/primary language impairment (PLI). Children with PLI show consistently poorer performance in non-word repetition tasks than their typically developing language (TDL) counterparts. It is assumed that the ability to repeat non-words triggers language skills and that the absence of this ability may be responsible for language impairment in PLI children. Twenty preschool children with PLI participated in this study and were compared with 31 peers whose language skills were developing typically. The TDL children were randomly selected from daycare centers, and the children with PLI were referred by qualified speech-language pathologists from speech therapy clinics. A Persian NWR test was administered and scored using two levels of scoring: item-level scoring and syllable-level scoring. Data were analyzed in two phases. The first phase aimed to determine any differences between the two groups of children in terms of NWR ability. The second phase examined the diagnostic measures of the test. The results of first phase documented that both scoring methods for the NWR test significantly differentiated between children with PLI and their normal peers. The second phase indicated that both scoring methods for the NWR test have good sensitivity and specificity in differentiating Persian-speaking children with PLI from their normal peers. Non-word repetition can be a reliable clinical marker of PLI in Persian-speaking preschool children. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

A systematic review and meta-analysis of randomized controlled trials of the effect of konjac glucomannan, a viscous soluble fiber, on LDL cholesterol and the new lipid targets non-HDL cholesterol and apolipoprotein B.

PubMed

Ho, Hoang Vi Thanh; Jovanovski, Elena; Zurbau, Andreea; Blanco Mejia, Sonia; Sievenpiper, John L; Au-Yeung, Fei; Jenkins, Alexandra L; Duvnjak, Lea; Leiter, Lawrence; Vuksan, Vladimir

2017-05-01

Background: Evidence from randomized controlled trials (RCTs) suggests the consumption of konjac glucomannan (KJM), a viscous soluble fiber, for improving LDL-cholesterol concentrations. It has also been suggested that the cholesterol-lowering potential of KJM may be greater than that of other fibers. However, trials have been relatively scarce and limited in sample size and duration, and the effect estimates have been inconsistent. The effect of KJM on new lipid targets of cardiovascular disease (CVD) risk is also unknown. Objective: This systematic review and meta-analysis aimed to assess the effect of KJM on LDL cholesterol, non-HDL cholesterol, and apolipoprotein B. Design: Medline, Embase, CINAHL, and the Cochrane Central databases were searched. We included RCTs with a follow-up of ≥3 wk that assessed the effect of KJM on LDL cholesterol, non-HDL cholesterol, or apolipoprotein B. Data were pooled by using the generic inverse-variance method with random-effects models and expressed as mean differences (MDs) with 95% CIs. Heterogeneity was assessed by the Cochran Q statistic and quantified by the I 2 statistic. Results: Twelve studies ( n = 370), 8 in adults and 4 in children, met the inclusion criteria. KJM significantly lowered LDL cholesterol (MD: -0.35 mmol/L; 95% CI: -0.46, -0.25 mmol/L) and non-HDL cholesterol (MD: -0.32 mmol/L; 95% CI: -0.46, -0.19 mmol/L). Data from 6 trials suggested no impact of KJM on apolipoprotein B. Conclusions: Our findings support the intake of ∼3 g KJM/d for reductions in LDL cholesterol and non-HDL cholesterol of 10% and 7%, respectively. The information may be of interest to health agencies in crafting future dietary recommendations related to reduction in CVD risk. This study was registered at clinicaltrials.gov as NCT02068248. © 2017 American Society for Nutrition.

Influence of magnetic disorders on quantum anomalous Hall effect in magnetic topological insulator films beyond the two-dimensional limit

NASA Astrophysics Data System (ADS)

Xing, Yanxia; Xu, Fuming; Cheung, King Tai; Sun, Qing-feng; Wang, Jian; Yao, Yugui

2018-04-01

Quantum anomalous Hall effect (QAHE) has been experimentally realized in magnetic topological insulator (MTI) thin films fabricated on magnetically doped {({{Bi}},{{Sb}})}2{{{Te}}}3. In an MTI thin film with the magnetic easy axis along the normal direction (z-direction), orientations of magnetic dopants are randomly distributed around the magnetic easy axis, acting as magnetic disorders. With the aid of the non-equilibrium Green's function and Landauer–Büttiker formalism, we numerically study the influence of magnetic disorders on QAHE in an MTI thin film modeled by a three-dimensional tight-binding Hamiltonian. It is found that, due to the existence of gapless side surface states, QAHE is protected even in the presence of magnetic disorders as long as the z-component of magnetic moment of all magnetic dopants are positive. More importantly, such magnetic disorders also suppress the dissipation of the chiral edge states and enhance the quality of QAHE in MTI films. In addition, the effect of magnetic disorders depends very much on the film thickness, and the optimal influence is achieved at certain thickness. These findings are new features for QAHE in three-dimensional systems, not present in two-dimensional systems.

THE CONTRIBUTIONS OF NORMAL AND ANOMALOUS OSMOSIS TO THE OSMOTIC EFFECTS ARISING ACROSS CHARGED MEMBRANES WITH SOLUTIONS OF ELECTROLYTES

PubMed Central

Grim, Eugene; Sollner, Karl

1957-01-01

The osmotic effect arising across a porous membrane separating the solution of an electrolyte from water (or a more dilute solution) is ordinarily due to both normal osmosis, as it occurs also with non-electrolytes, and to "anomalous" osmosis. It is shown that the normal osmotic component cannot be measured quantitatively by the conventional comparison with a non-electrolytic reference solute. Anomalous osmosis does not occur with electroneutral membranes. Accordingly, with membranes which can be charged and discharged reversibly (without changes in geometrical structure), such as many proteinized membranes, the osmotic effects caused by an electrolyte can be measured both when only normal osmosis arises (with the membrane in the electroneutral state) and when normal as well as anomalous osmosis occurs (with the membrane in a charged state). The difference between these two effects is the true anomalous osmosis. Data are presented on the osmotic effects across an oxyhemoglobin membrane in the uncharged state at pH 6.75 and in two charged states, positive at pH 4.0 and negative at pH 10.0, with solutions of a variety of electrolytes using a concentration ratio of 2:1 over a wide range of concentrations. The rates of the movement of liquid across the membrane against an inconsequentially small hydrostatic head are recorded instead of, as conventional, the physiologically less significant pressure rises after a standard time. PMID:13439166

Effects of Dietary Protein and Fiber at Breakfast on Appetite, ad Libitum Energy Intake at Lunch, and Neural Responses to Visual Food Stimuli in Overweight Adults

PubMed Central

Sayer, R. Drew; Amankwaah, Akua F.; Tamer, Gregory G.; Chen, Ningning; Wright, Amy J.; Tregellas, Jason R.; Cornier, Marc-Andre; Kareken, David A.; Talavage, Thomas M.; McCrory, Megan A.; Campbell, Wayne W.

2016-01-01

Increasing either protein or fiber at mealtimes has relatively modest effects on ingestive behavior. Whether protein and fiber have additive or interactive effects on ingestive behavior is not known. Fifteen overweight adults (5 female, 10 male; BMI: 27.1 ± 0.2 kg/m2; aged 26 ± 1 year) consumed four breakfast meals in a randomized crossover manner (normal protein (12 g) + normal fiber (2 g), normal protein (12 g) + high fiber (8 g), high protein (25 g) + normal fiber (2 g), high protein (25 g) + high fiber (8 g)). The amount of protein and fiber consumed at breakfast did not influence postprandial appetite or ad libitum energy intake at lunch. In the fasting-state, visual food stimuli elicited significant responses in the bilateral insula and amygdala and left orbitofrontal cortex. Contrary to our hypotheses, postprandial right insula responses were lower after consuming normal protein vs. high protein breakfasts. Postprandial responses in other a priori brain regions were not significantly influenced by protein or fiber intake at breakfast. In conclusion, these data do not support increasing dietary protein and fiber at breakfast as effective strategies for modulating neural reward processing and acute ingestive behavior in overweight adults. PMID:26742068

Effects of Dietary Protein and Fiber at Breakfast on Appetite, ad Libitum Energy Intake at Lunch, and Neural Responses to Visual Food Stimuli in Overweight Adults.

PubMed

Sayer, R Drew; Amankwaah, Akua F; Tamer, Gregory G; Chen, Ningning; Wright, Amy J; Tregellas, Jason R; Cornier, Marc-Andre; Kareken, David A; Talavage, Thomas M; McCrory, Megan A; Campbell, Wayne W

2016-01-05

Increasing either protein or fiber at mealtimes has relatively modest effects on ingestive behavior. Whether protein and fiber have additive or interactive effects on ingestive behavior is not known. Fifteen overweight adults (5 female, 10 male; BMI: 27.1 ± 0.2 kg/m²; aged 26 ± 1 year) consumed four breakfast meals in a randomized crossover manner (normal protein (12 g) + normal fiber (2 g), normal protein (12 g) + high fiber (8 g), high protein (25 g) + normal fiber (2 g), high protein (25 g) + high fiber (8 g)). The amount of protein and fiber consumed at breakfast did not influence postprandial appetite or ad libitum energy intake at lunch. In the fasting-state, visual food stimuli elicited significant responses in the bilateral insula and amygdala and left orbitofrontal cortex. Contrary to our hypotheses, postprandial right insula responses were lower after consuming normal protein vs. high protein breakfasts. Postprandial responses in other a priori brain regions were not significantly influenced by protein or fiber intake at breakfast. In conclusion, these data do not support increasing dietary protein and fiber at breakfast as effective strategies for modulating neural reward processing and acute ingestive behavior in overweight adults.

The effect of palm oil, lard, and puff-pastry margarine on postprandial lipid and hormone responses in normal-weight and obese young women.

PubMed

Jensen, J; Bysted, A; Dawids, S; Hermansen, K; Hølmer, G

1999-12-01

Only a few studies have been published on the postprandial effects of different fatty acids in obese subjects. Therefore, the present study investigated the effects of three test meals containing palm oil (PO), lard (LD), or puff-pastry margarine (PPM), all normal dietary ingredients, on postprandial lipid and hormone responses in normal-weight and obese young women. The study was performed as a randomized, crossover design. The fats differed in the content of palmitic acid, stearic acid, and trans monounsaturated fatty acids allowing a dietary comparison of different 'solid' fatty acids. The obese women had significantly higher fasting concentrations and postprandial responses of plasma total triacylglycerol (TAG), chylomicron-TAG, and insulin compared with the normal-weight women but there was no significant difference in the postprandial responses between the three test meals. The obese women had fasting concentrations of leptin four times greater than the normal-weight women. There were no postprandial changes in the concentrations of leptin. The fasting concentrations of HDL-cholesterol were significantly lower in the obese women than in the normal-weight women, whereas there was no significant difference between the two groups in the concentrations of total cholesterol or LDL-cholesterol. These results provide evidence that obese women have exaggerated lipid and hormone responses compared with normal-weight women but the different contents of saturated and trans monounsaturated fatty acids provided by PO, LD, and PPM have no effect in either group.

Multivariate non-normally distributed random variables in climate research - introduction to the copula approach

NASA Astrophysics Data System (ADS)

Schölzel, C.; Friederichs, P.

2008-10-01

Probability distributions of multivariate random variables are generally more complex compared to their univariate counterparts which is due to a possible nonlinear dependence between the random variables. One approach to this problem is the use of copulas, which have become popular over recent years, especially in fields like econometrics, finance, risk management, or insurance. Since this newly emerging field includes various practices, a controversial discussion, and vast field of literature, it is difficult to get an overview. The aim of this paper is therefore to provide an brief overview of copulas for application in meteorology and climate research. We examine the advantages and disadvantages compared to alternative approaches like e.g. mixture models, summarize the current problem of goodness-of-fit (GOF) tests for copulas, and discuss the connection with multivariate extremes. An application to station data shows the simplicity and the capabilities as well as the limitations of this approach. Observations of daily precipitation and temperature are fitted to a bivariate model and demonstrate, that copulas are valuable complement to the commonly used methods.

Statistical analysis of multivariate atmospheric variables. [cloud cover

NASA Technical Reports Server (NTRS)

Tubbs, J. D.

1979-01-01

Topics covered include: (1) estimation in discrete multivariate distributions; (2) a procedure to predict cloud cover frequencies in the bivariate case; (3) a program to compute conditional bivariate normal parameters; (4) the transformation of nonnormal multivariate to near-normal; (5) test of fit for the extreme value distribution based upon the generalized minimum chi-square; (6) test of fit for continuous distributions based upon the generalized minimum chi-square; (7) effect of correlated observations on confidence sets based upon chi-square statistics; and (8) generation of random variates from specified distributions.

Reflectivity of a disordered monolayer estimated by graded refractive index and scattering models.

PubMed

Diamant, Ruth; Garcí-Valenzuela, Augusto; Fernández-Guasti, Manuel

2012-09-01

Reflectivity of a random monolayer, consisting of transparent spherical particles, is estimated using a graded refractive index model, an effective medium approach, and two scattering models. Two cases, a self-standing film and one with a substrate, are considered. Neither the surrounding medium nor the substrate are absorbing materials. Results at normal incidence, with different particle sizes, covering ratios and refractive indexes, are compared. The purpose of this work is to find under which circumstances, for reflectivity at normal incidence, a particle monolayer behaves as a graded refractive index film.

Bright ambient light conditions reduce the effect of tryptophan depletion in healthy females.

PubMed

Defrancesco, Michaela; Niederstätter, Harald; Parson, Walther; Kemmler, Georg; Hinterhuber, Hartmann; Marksteiner, Josef; Deisenhammer, Eberhard A

2013-11-30

Tryptophan depletion (TD) is an established method to influence the serotonergic system and mood. The purpose of this study was to examine the effect of TD under different ambient light conditions, measured through serotonin-associated plasma levels and a visual analog scale (VAS), on healthy females. Thirty-eight healthy female s-allele carriers of the serotonin transporter promoter gene (5-HTTLPR) were administered a TD under dim light conditions (75 lx). A sub-group of 8 participants repeated the procedure randomized in two additional light conditions (585 lx and 1530 lx respectively). Prior to, and 5h following administration of TD, various variables (serotonin-associated plasma levels, VAS) were measured. Due to not normal distributed data, non-parametric statistical tests were used. Overall analysis showed a significant mood lowering effect of TD. Moreover, TD decreased all measured serotonin-associated plasma levels significantly. Significant differences in varying light conditions were found for the VAS and plasma tryptophan, with the greatest effect of TD in the 75 lx condition. Results of our study showed an influence of even slight differences in ambient light intensity on the effect of TD concerning mood as well as on the serotonergic system. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

The impact of weight changes on nonalcoholic Fatty liver disease in adult men with normal weight.

PubMed

Cho, Ji-Young; Chung, Tae-Heum; Lim, Kyoung-Mo; Park, Hee-Jin; Jang, Jung-Mi

2014-09-01

Although it is known that losing weight has an effect on the treatment of non-alcoholic fatty liver disease, the studies that show how losing weight affects the non-alcoholic fatty liver disease for the normal weight male adults are limited so far. In this study, we set body mass index as criteria and investigated how the weight changes for 4 years makes an impact on the risk of non-alcoholic fatty liver disease for the male adults who have the normal body mass index. From January to December of 2004, among the normal weight male adults who had general check-up at the Health Promotion Center of Ulsan University Hospital, 180 people (average age, 47.4 ± 4.61 years) who were diagnosed with fatty liver through abdominal ultrasonography were included in this study and were observed according to the variety of data and ultrasonography after 4 years (2008). People who had a history of drinking more than 140 g of alcohol per week or who had a past medical history were excluded from the analysis. The weight change of subjects was calculated using the formula 'weight change = weight of 2008 (kg) - weight of 2004 (kg)' and classified into three groups, loss group (≤-3.0 kg), stable group (-2.9 to 2.9 kg), and gain group (≥3.0 kg). The odds for disappearance of non-alcoholic fatty liver disease in those three different groups were compared. Among 180 subjects, compared with stable group (67.2%, 121 subjects), loss group (11.7%, 21 subjects) showed 18.37-fold increase in the odds of disappearance of non-alcoholic fatty liver disease (95% confidence interval [CI], 4.34 to 77.80) and gain group (21.1%, 38 subjects) showed 0.28-fold decrease in the odds of disappearance of non-alcoholic fatty liver disease (95% CI, 0.10 to 0.83). Even for the normal weight people, losing weight has an effect on the improvement of non-alcoholic fatty liver disease.

Molecular motion in cell membranes: Analytic study of fence-hindered random walks

NASA Astrophysics Data System (ADS)

Kenkre, V. M.; Giuggioli, L.; Kalay, Z.

2008-05-01

A theoretical calculation is presented to describe the confined motion of transmembrane molecules in cell membranes. The study is analytic, based on Master equations for the probability of the molecules moving as random walkers, and leads to explicit usable solutions including expressions for the molecular mean square displacement and effective diffusion constants. One outcome is a detailed understanding of the dependence of the time variation of the mean square displacement on the initial placement of the molecule within the confined region. How to use the calculations is illustrated by extracting (confinement) compartment sizes from experimentally reported published observations from single particle tracking experiments on the diffusion of gold-tagged G -protein coupled μ -opioid receptors in the normal rat kidney cell membrane, and by further comparing the analytical results to observations on the diffusion of phospholipids, also in normal rat kidney cells.

Effect of an Online Video-Based Intervention to Increase HIV Testing in Men Who Have Sex with Men in Peru

PubMed Central

Blas, Magaly M.; Alva, Isaac E.; Carcamo, Cesar P.; Cabello, Robinson; Goodreau, Steven M.; Kimball, Ann M.; Kurth, Ann E.

2010-01-01

Background Although many men who have sex with men (MSM) in Peru are unaware of their HIV status, they are frequent users of the Internet, and can be approached by that medium for promotion of HIV testing. Methods We conducted an online randomized controlled trial to compare the effect of HIV-testing motivational videos versus standard public health text, both offered through a gay website. The videos were customized for two audiences based on self-identification: either gay or non-gay men. The outcomes evaluated were ‘intention to get tested’ and ‘HIV testing at the clinic.’ Findings In the non-gay identified group, 97 men were randomly assigned to the video-based intervention and 90 to the text-based intervention. Non-gay identified participants randomized to the video-based intervention were more likely to report their intention of getting tested for HIV within the next 30 days (62.5% vs. 15.4%, Relative Risk (RR): 2.77, 95% Confidence Interval (CI): 1.42–5.39). After a mean of 125.5 days of observation (range 42–209 days), 11 participants randomized to the video and none of the participants randomized to text attended our clinic requesting HIV testing (p = 0.001). In the gay-identified group, 142 men were randomized to the video-based intervention and 130 to the text-based intervention. Gay-identified participants randomized to the video were more likely to report intentions of getting an HIV test within 30 days, although not significantly (50% vs. 21.6%, RR: 1.54, 95% CI: 0.74–3.20). At the end of follow up, 8 participants who watched the video and 10 who read the text visited our clinic for HIV testing (Hazard Ratio: 1.07, 95% CI: 0.40–2.85). Conclusion This study provides some evidence of the efficacy of a video-based online intervention in improving HIV testing among non-gay-identified MSM in Peru. This intervention may be adopted by institutions with websites oriented to motivate HIV testing among similar MSM populations. Trial registration Clinicaltrials.gov NCT00751192 PMID:20454667

Effect of an online video-based intervention to increase HIV testing in men who have sex with men in Peru.

PubMed

Blas, Magaly M; Alva, Isaac E; Carcamo, Cesar P; Cabello, Robinson; Goodreau, Steven M; Kimball, Ann M; Kurth, Ann E

2010-05-03

Although many men who have sex with men (MSM) in Peru are unaware of their HIV status, they are frequent users of the Internet, and can be approached by that medium for promotion of HIV testing. We conducted an online randomized controlled trial to compare the effect of HIV-testing motivational videos versus standard public health text, both offered through a gay website. The videos were customized for two audiences based on self-identification: either gay or non-gay men. The outcomes evaluated were 'intention to get tested' and 'HIV testing at the clinic.' In the non-gay identified group, 97 men were randomly assigned to the video-based intervention and 90 to the text-based intervention. Non-gay identified participants randomized to the video-based intervention were more likely to report their intention of getting tested for HIV within the next 30 days (62.5% vs. 15.4%, Relative Risk (RR): 2.77, 95% Confidence Interval (CI): 1.42-5.39). After a mean of 125.5 days of observation (range 42-209 days), 11 participants randomized to the video and none of the participants randomized to text attended our clinic requesting HIV testing (p = 0.001). In the gay-identified group, 142 men were randomized to the video-based intervention and 130 to the text-based intervention. Gay-identified participants randomized to the video were more likely to report intentions of getting an HIV test within 30 days, although not significantly (50% vs. 21.6%, RR: 1.54, 95% CI: 0.74-3.20). At the end of follow up, 8 participants who watched the video and 10 who read the text visited our clinic for HIV testing (Hazard Ratio: 1.07, 95% CI: 0.40-2.85). This study provides some evidence of the efficacy of a video-based online intervention in improving HIV testing among non-gay-identified MSM in Peru. This intervention may be adopted by institutions with websites oriented to motivate HIV testing among similar MSM populations. Clinicaltrials.gov NCT00751192.

Pathophysiology of dysarthria in cerebral palsy.

PubMed Central

Neilson, P D; O'Dwyer, N J

1981-01-01

Electromyograms were recorded with hooked-wire electrodes from sixteen lip, tongue and jaw muscles in six normal and seven cerebral palsied adult subjects during a variety of speech and non-speech tasks. The recorded patterns of muscle activity fail to support a number of theories concerning the pathophysiology of dysarthria in cerebral palsy. There was no indication of weakness in individual articulator muscles. There was no evidence of uncontrolled sustained background activity or of abnormal tonic stretch reflex responses in lip or tongue muscles. Primitive or pathological reflexes could not be elicited by orofacial stimulation. No imbalance between positive and negative oral responses was observed. The view that random involuntary movement disrupts essentially normal voluntary control in athetosis was not supported. Each cerebral palsied subject displayed an idiosyncratic pattern of abnormal muscle activity which was reproduced across repetitions of the same phrase, indicating a consistent defect in motor programming. PMID:7334387

Analysis of Realized Volatility for Nikkei Stock Average on the Tokyo Stock Exchange

NASA Astrophysics Data System (ADS)

Takaishi, Tetsuya; Watanabe, Toshiaki

2016-04-01

We calculate realized volatility of the Nikkei Stock Average (Nikkei225) Index on the Tokyo Stock Exchange and investigate the return dynamics. To avoid the bias on the realized volatility from the non-trading hours issue we calculate realized volatility separately in the two trading sessions, i.e. morning and afternoon, of the Tokyo Stock Exchange and find that the microstructure noise decreases the realized volatility at small sampling frequency. Using realized volatility as a proxy of the integrated volatility we standardize returns in the morning and afternoon sessions and investigate the normality of the standardized returns by calculating variance, kurtosis and 6th moment. We find that variance, kurtosis and 6th moment are consistent with those of the standard normal distribution, which indicates that the return dynamics of the Nikkei Stock Average are well described by a Gaussian random process with time-varying volatility.

The dependence of binocular contrast sensitivities on binocular single vision in normal and amblyopic human subjects

PubMed Central

Hood, A S; Morrison, J D

2002-01-01

We have measured monocular and binocular contrast sensitivities in response to medium to high spatial frequencies of vertical sinusoidal grating patterns in normal subjects, anisometropic amblyopes, strabismic amblyopes and non-amblyopic esotropes. On binocular viewing, contrast sensitivities were slightly but significantly increased in normal subjects, markedly increased in anisometropes and esotropes with anomalous binocular single vision (BSV) and significantly reduced in esotropes and exotropes without BSV. Application of a prismatic correction to the strabismic eye in order to achieve bifoveal stimulation resulted in a significant reduction in contrast sensitivity in esotropes with and without anomalous BSV, in exotropes and in non-amblyopic esotropes. Control experiments in normal subjects with monocular viewing showed that degradative effects of the prism occurred only with high prism powers and at high spatial frequencies, thus establishing that the reduced contrast sensitivities were the consequence of bifoveal stimulation rather than optical degradation. Displacement of the image of the grating pattern by 2 deg in normal subjects and anisometropes by a dichoptic method to simulate a small angle esotropia had no effect on the contrast sensitivities recorded through the companion eye. By contrast, esotropes showed similar reductions in contrast sensitivity to those obtained with the prism experiments, confirming a fundamental difference between subjects with normal and abnormal ocular alignments. The results have thus established a suppressive action of the fovea of the amblyopic eye acting on the companion, non-amblyopic eye and indicate that correction of ocular misalignments in adult esotropes may be disadvantageous to binocular visual performance. PMID:11956347

Is a woolen cap effective in maintaining normothermia in low-birth-weight infants during kangaroo mother care? Study protocol for a randomized controlled trial.

PubMed

Trevisanuto, Daniele; Putoto, Giovanni; Pizzol, Damiano; Serena, Tiziana; Manenti, Fabio; Varano, Silvia; Urso, Eleonora; Massavon, William; Tsegaye, Ademe; Wingi, Oliver; Onapa, Emanuel; Segafredo, Giulia; Cavallin, Francesco

2016-05-26

Neonatal hypothermia is an important challenge associated with morbidity and mortality. Preventing neonatal hypothermia is important in high-resource countries, but is of fundamental importance in low-resource settings where supportive care is limited. Kangaroo mother care (KMC) is a low-cost intervention that, whenever possible, is strongly recommended for temperature maintenance. During KMC, the World Health Organization (WHO) guidelines recommend the use of a cap/hat, but its effect on temperature control during KMC remains to be established. In the hospitals participating in the projects of the non-governmental organization CUAMM, KMC represents a standard of care, but the heads of the babies often remain uncovered due to local habits or to the unavailability of a cap. The aim of the present study will be to assess the effectiveness and safety of using a woolen cap in maintaining normothermia in low-birth-weight infants (LBWI) during KMC. This is a multicenter (three hospitals), multicountry (three countries), prospective, unblinded, randomized controlled trial of KMC treatment with and without a woolen cap in LBWI. After obtaining parental consent, all infants with a birth weight below 2500 g and who are candidates for KMC, based on the clinical decision of the attending physician, will be assigned to the KMC with a woolen cap group or to the KMC without a woolen cap group in a 1:1 ratio according to a computer-generated, randomized sequence. The duration of the study will be until the patient's discharge, with a maximum treatment duration of 7 days. The primary outcome measure will be whether the infants' temperatures remain within the normal range (36.5-37.5 °C) in the course of KMC during the intervention. In all participants, axillary temperature will be measured with a digital thermometer four times per day. In addition, maternal and room temperature will be recorded. Secondary outcome measures will be: episodes of apnea; sepsis; mortality before hospital discharge; in-hospital growth; and age at discharge. The findings of this study will be important for other units/settings in high- as well low-resource countries where KMC is routinely performed. Based on the results of the present study, we could speculate whether the use of a woolen cap may help to maintain the neonate within the normal thermal range. Furthermore, potential complications such as hyperthermia will be strictly monitored and collected. ClinicalTrials.gov Identifier: NCT02645526 (registered on 31 December 2015).

Chronic Inhibition, Self-Control and Eating Behavior: Test of a ‘Resource Depletion’ Model

PubMed Central

Hagger, Martin S.; Panetta, Giulia; Leung, Chung-Ming; Wong, Ging Ging; Wang, John C. K.; Chan, Derwin K. C.; Keatley, David A.; Chatzisarantis, Nikos L. D.

2013-01-01

The current research tested the hypothesis that individuals engaged in long-term efforts to limit food intake (e.g., individuals with high eating restraint) would have reduced capacity to regulate eating when self-control resources are limited. In the current research, body mass index (BMI) was used as a proxy for eating restraint based on the assumption that individuals with high BMI would have elevated levels of chronic eating restraint. A preliminary study (Study 1) aimed to provide evidence for the assumed relationship between eating restraint and BMI. Participants (N = 72) categorized into high or normal-range BMI groups completed the eating restraint scale. Consistent with the hypothesis, results revealed significantly higher scores on the weight fluctuation and concern for dieting subscales of the restraint scale among participants in the high BMI group compared to the normal-range BMI group. The main study (Study 2) aimed to test the hypothesized interactive effect of BMI and diminished self-control resources on eating behavior. Participants (N = 83) classified as having high or normal-range BMI were randomly allocated to receive a challenging counting task that depleted self-control resources (ego-depletion condition) or a non-depleting control task (no depletion condition). Participants then engaged in a second task in which required tasting and rating tempting cookies and candies. Amount of food consumed during the taste-and-rate task constituted the behavioral dependent measure. Regression analyses revealed a significant interaction effect of these variables on amount of food eaten in the taste-and-rate task. Individuals with high BMI had reduced capacity to regulate eating under conditions of self-control resource depletion as predicted. The interactive effects of BMI and self-control resource depletion on eating behavior were independent of trait self-control. Results extend knowledge of the role of self-control in regulating eating behavior and provide support for a limited-resource model of self-control. PMID:24146942

Fluid resuscitation with lactated Ringer’s solution vs normal saline in acute pancreatitis: A triple-blind, randomized, controlled trial

PubMed Central

Herrera-Marante, Iván; González-Camacho, Verónica; Bonjoch, Laia; Quesada-Vázquez, Noé; Almenta-Saavedra, Isabel; Miralles-Maciá, Cayetano; Acevedo-Piedra, Nelly G; Roger-Ibáñez, Manuela; Sánchez-Marin, Claudia; Osuna-Ligero, Rosa; Gracia, Ángel; Llorens, Pere; Zapater, Pedro; Singh, Vikesh K; Moreu-Martín, Rocío; Closa, Daniel

2017-01-01

Background Little is known regarding the optimal type of fluid resuscitation in acute pancreatitis (AP). Objective The objective of this article was to compare the effect of lactated Ringer’s solution (LR) vs normal saline (NS) in the inflammatory response in AP. Methods We conducted a triple-blind, randomized, controlled trial. Patients ≥ 18 admitted with AP were eligible. Patients were randomized to receive LR or NS. Primary outcome variables were number of systemic inflammatory response syndrome (SIRS) criteria at 24 hours, 48 hours and 72 hours and blood C-reactive protein (CRP) levels at 48 hours and 72 hours. In vitro complementary experiments were performed to further explore the interaction between pH, lactate and inflammation. Results Nineteen patients receiving LR and 21 receiving NS were analyzed. The median (p25–p75) number of SIRS criteria at 48 hours were 1 (1–2) for NS vs 1 (0–1) for LR, p = 0.060. CRP levels (mg/l) were as follows: at 48 hours NS 166 (78–281) vs LR 28 (3–124), p = 0.037; at 72 hours NS 217 (59–323) vs LR 25 (3–169), p = 0.043. In vitro, LR inhibited the induction of inflammatory phenotype of macrophages and NF-κB activation. This effect was not observed when using Ringer’s solution without lactate, suggesting a direct anti-inflammatory effect of lactate. Conclusions Lactated Ringer’s is associated with an anti-inflammatory effect in patients with acute pancreatitis. PMID:29435315

A Bayesian ridge regression analysis of congestion's impact on urban expressway safety.

PubMed

Shi, Qi; Abdel-Aty, Mohamed; Lee, Jaeyoung

2016-03-01

With the rapid growth of traffic in urban areas, concerns about congestion and traffic safety have been heightened. This study leveraged both Automatic Vehicle Identification (AVI) system and Microwave Vehicle Detection System (MVDS) installed on an expressway in Central Florida to explore how congestion impacts the crash occurrence in urban areas. Multiple congestion measures from the two systems were developed. To ensure more precise estimates of the congestion's effects, the traffic data were aggregated into peak and non-peak hours. Multicollinearity among traffic parameters was examined. The results showed the presence of multicollinearity especially during peak hours. As a response, ridge regression was introduced to cope with this issue. Poisson models with uncorrelated random effects, correlated random effects, and both correlated random effects and random parameters were constructed within the Bayesian framework. It was proven that correlated random effects could significantly enhance model performance. The random parameters model has similar goodness-of-fit compared with the model with only correlated random effects. However, by accounting for the unobserved heterogeneity, more variables were found to be significantly related to crash frequency. The models indicated that congestion increased crash frequency during peak hours while during non-peak hours it was not a major crash contributing factor. Using the random parameter model, the three congestion measures were compared. It was found that all congestion indicators had similar effects while Congestion Index (CI) derived from MVDS data was a better congestion indicator for safety analysis. Also, analyses showed that the segments with higher congestion intensity could not only increase property damage only (PDO) crashes, but also more severe crashes. In addition, the issues regarding the necessity to incorporate specific congestion indicator for congestion's effects on safety and to take care of the multicollinearity between explanatory variables were also discussed. By including a specific congestion indicator, the model performance significantly improved. When comparing models with and without ridge regression, the magnitude of the coefficients was altered in the existence of multicollinearity. These conclusions suggest that the use of appropriate congestion measure and consideration of multicolilnearity among the variables would improve the models and our understanding about the effects of congestion on traffic safety. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effect of low-level laser therapy on pain and perineal healing after episiotomy: A triple-blind randomized controlled trial.

PubMed

Alvarenga, Marina B; de Oliveira, Sonia Maria Junqueira Vasconcellos; Francisco, Adriana A; da Silva, Flora Maria B; Sousa, Marcelo; Nobre, Moacyr Roberto

2017-02-01

Episiotomy is associated with perineal pain and healing complications. The low-level laser therapy (LLLT) reduces pain and inflammation and stimulates the healing process. This study aimed to assess the effect of LLLT on pain and perineal healing after an episiotomy. A randomized, triple-blind, parallel clinical trial with 54 postpartum women who had a spontaneous birth with a right mediolateral episiotomy. The women were randomized into two groups: the experimental group (applications of LLLT n = 29) or the placebo group (simulated LLLT applications n = 25). Three sessions of real or sham irradiation were performed at 6-10 hours after normal birth, and the 2nd and 3rd applications were performed at 20-24 hours and 40-48 hours after the first session, respectively. Perineal pain was recorded using a Numeric Scale ranging from 0 to 10 (0 = absence and 10 = worst pain). Perineal healing was assessed using the redness, oedema, ecchymosis, discharge, and approximation (REEDA) scale. Both groups were assessed four times: in each of the three LLLT sessions and at 7-10 days after normal birth. The groups were compared using the Student's t, Mann-Whitney, and Chi-square tests. There was no significant difference between the groups regarding perineal healing after LLLT. The perineal pain scores were statistically higher in the experimental group in the first assessment and after the third LLLT. There was no significant difference between the groups related to the perineal pain scores 7-10 days after normal birth. The use of LLLT does not provide any benefit for treating postpartum perineal trauma using these specific protocol and parameters. Lasers Surg. Med. 49:181-188, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Renal denervation in heart failure with normal left ventricular ejection fraction. Rationale and design of the DIASTOLE (DenervatIon of the renAl Sympathetic nerves in hearT failure with nOrmal Lv Ejection fraction) trial.

PubMed

Verloop, Willemien L; Beeftink, Martine M A; Nap, Alex; Bots, Michiel L; Velthuis, Birgitta K; Appelman, Yolande E; Cramer, Maarten-Jan; Agema, Willem R P; Scholtens, Asbjorn M; Doevendans, Pieter A; Allaart, Cor P; Voskuil, Michiel

2013-12-01

Aim Increasing evidence suggests an important role for hyperactivation of the sympathetic nervous system (SNS) in the clinical phenomena of heart failure with normal LVEF (HFNEF) and hypertension. Moreover, the level of renal sympathetic activation is directly related to the severity of heart failure. Since percutaneous renal denervation (pRDN) has been shown to be effective in modulating elevated SNS activity in patients with hypertension, it can be hypothesized that pRDN has a positive effect on HFNEF. The DIASTOLE trial will investigate whether renal sympathetic denervation influences parameters of HFNEF. Methods DIASTOLE is a multicentre, randomized controlled trial. Sixty patients, diagnosed with HFNEF and treated for hypertension, will be randomly allocated in a 1:1 ratio to undergo renal denervation on top of medical treatment (n = 30) or to maintain medical treatment alone (n = 30). The primary objective is to investigate the efficacy of pRDN by means of pulsed wave Doppler echocardiographic parameters. Secondary objectives include safety of pRDN and a comparison of changes in the following parameters after pRDN: LV mass, LV volume, LVEF, and left atrial volume as determined by magnetic resonance imaging. Also, MIBG (metaiodobenzylguanidine) uptake and washout, BNP levels, blood pressure, heart rate variability, exercise capacity, and quality of life will be assessed. Perspective DIASTOLE is a randomized controlled trial evaluating renal denervation as a treatment option for HFNEF. The results of the current trial will provide important information regarding the treatment of HFNEF, and therefore may have major impact on future therapeutic strategies. Trail registration NCT01583881.

Combined spinal-epidural anesthesia and non-pharmacological methods of pain relief during normal childbirth and maternal satisfaction: a randomized clinical trial.

PubMed

Orange, Flavia Augusta de; Passini, Renato; Melo, Adriana S O; Katz, Leila; Coutinho, Isabela Cristina; Amorim, Melania M R

2012-01-01

The objective of this study was to compare maternal satisfaction with childbirth according to whether or not combined spinal-epidural anesthesia (CSE) of pain relief was used during labor. A randomized, open clinical trial was performed with 70 pregnant women, 35 of whom received CSE anesthesia while 35 received only non-pharmacological forms of pain relief during labor. The variables evaluated were visual analogue scale (VAS) pain score, maternal satisfaction with the technique of pain relief used during childbirth and with delivery, the patient's intention to request the same technique in a subsequent delivery, and loss of control during delivery. VAS pain score decreased significantly in patients receiving CSE during vaginal delivery. Furthermore, maternal satisfaction with the technique of pain relief and with delivery was higher in the CSE group, and around 97% of the patients would repeat the same technique at future deliveries compared to 82.4% of the women in the group using only non-pharmacological methods. With respect to the women's impressions of their control during delivery, approximately half the women in both groups felt that they had lost control at some point during the process. The use of CSE was associated with a significant reduction in VAS pain scores during delivery and with greater maternal satisfaction with the pain relief method and with the childbirth process.

Medical audit of rectal biopsy diagnosis of inflammatory bowel disease.

PubMed

Frei, J V; Morson, B C

1982-03-01

The records of the rectal biopsy diagnoses of ulcerative colitis and Crohn's disease in the Department of Pathology, St Mark's Hospital, London, were reviewed. The biopsy diagnoses were compared to subsequent resection diagnoses on the same patients, and annual and seasonal variations in the frequency of these and related diagnoses were studied. The accuracy rate for the biopsy diagnosis of ulcerative colitis was about 70% and for Crohn's disease about 40% each time a biopsy was read. The low figure for the accuracy rate for Crohn's disease could be attributed to sampling error inherent in the diagnosis of a disease which is essentially patchy, showing discontinuous pathology. Also, many patients with Crohn's disease have a normal rectum which is biopsied to demonstrate the distinction from ulcerative colitis. In practical terms therefore a 40% accuracy rate in Crohn's disease is probably adequate. The rate of "false-positive" diagnoses was about 5%. There was a seasonal variation in the frequency of these two diagnoses, but no variation attributable to changes in observers, as pathology trainees in the Department change regularly. The frequency of diagnoses of non-specific inflammation and of normal colon did show such non-random variations.

Non-steroidal anti-inflammatory drugs for the common cold.

PubMed

Kim, Soo Young; Chang, Yoon-Jung; Cho, Hye Min; Hwang, Ye-Won; Moon, Yoo Sun

2015-09-21

Non-steroidal anti-inflammatory drugs (NSAIDs) have been widely used for the treatment of pain and fever associated with the common cold. To determine the effects of NSAIDs versus placebo (and other treatments) on signs and symptoms of the common cold, and to determine any adverse effects of NSAIDs in people with the common cold. We searched CENTRAL (2015, Issue 4, April), (January 1966 to April week 3, 2015), EMBASE (January 1980 to April 2015), CINAHL (January 1982 to April 2015) and ProQuest Digital Dissertations (January 1938 to April 2015). Randomised controlled trials (RCTs) of NSAIDS in adults or children with the common cold. Four review authors extracted data. We subdivided trials into placebo-controlled RCTs and head-to-head comparisons of NSAIDs. We extracted and summarised data on global analgesic effects (such as reduction of headache and myalgia), non-analgesic effects (such as reduction of nasal symptoms, cough, sputum and sneezing) and side effects. We expressed dichotomous outcomes as risk ratios (RR) with 95% confidence intervals (CI) and continuous data as mean differences (MD) or standardised mean differences (SMD). We pooled data using the fixed-effect and random-effects models. We included nine RCTs with 1069 participants, describing 37 comparisons: six were NSAIDs versus placebo and three were NSAIDs versus NSAIDs. The overall risk of bias in the included studies was mixed. In a pooled analysis, NSAIDs did not significantly reduce the total symptom score (SMD -0.40, 95% CI -1.03 to 0.24, three studies, random-effects model), or duration of colds (MD -0.23, 95% CI -1.75 to 1.29, two studies, random-effects model). For respiratory symptoms, cough did not improve (SMD -0.05, 95% CI -0.66 to 0.56, two studies, random-effects model) but the sneezing score significantly improved (SMD -0.44, 95% CI -0.75 to -0.12, two studies, random-effects model). For outcomes related to the analgesic effects of NSAIDs (headache, ear pain, and muscle and joint pain) the treatment produced significant benefits. The risk of adverse effects was not high with NSAIDs (RR 2.94, 95% CI 0.51 to 17.03, two studies, random-effects model) but it is difficult to conclude that such drugs are no different from placebo. The quality of the evidence may be estimated as 'moderate' because of imprecision. The major limitations of this review are that the results of the studies are quite diverse and the number of studies for one result is quite small. NSAIDs are somewhat effective in relieving the discomfort caused by a cold but there is no clear evidence of their effect in easing respiratory symptoms. The balance of benefit and harms needs to be considered when using NSAIDs for colds.

Non-steroidal anti-inflammatory drugs for the common cold.

PubMed

Kim, Soo Young; Chang, Yoon-Jung; Cho, Hye Min; Hwang, Ye-Won; Moon, Yoo Sun

2013-06-04

Non-steroidal anti-inflammatory drugs (NSAIDs) have been widely used for the treatment of pain and fever associated with the common cold. However, there is no systematic review to assess the effects of NSAIDs in treating the common cold. To determine the effects of NSAIDs versus placebo (and other treatments) on signs and symptoms of the common cold, and to determine any adverse effects of NSAIDs in people with the common cold. We searched CENTRAL (The Cochrane Library 2013, Issue 1), MEDLINE (January 1966 to April week 4, 2013), EMBASE (January 1980 to April 2013), CINAHL (January 1982 to April 2013) and ProQuest Digital Dissertations (January 1938 to April 2013). Randomised controlled trials (RCTs) of NSAIDS in adults or children with the common cold. Four review authors extracted data. We subdivided trials into placebo-controlled RCTs and head-to-head comparisons of NSAIDs. We extracted and summarised data on global efficacies of analgesic effects (such as reduction of headache and myalgia), non-analgesic effects (such as reduction of nasal symptoms, cough, sputum and sneezing) and side effects. We expressed dichotomous outcomes as risk ratios (RR) with 95% confidence intervals (CI) and continuous data as mean differences (MD) or standardised mean differences (SMD). We pooled data using the fixed- and random-effects models. We included nine RCTs with 1069 participants, describing 37 comparisons: six were NSAIDs versus placebo and three were NSAIDs versus NSAIDs. The overall risk of bias in the included studies was mixed. In a pooled analysis, NSAIDs did not significantly reduce the total symptom score (SMD -0.40, 95% CI -1.03 to 0.24, three studies, random-effects model), or duration of colds (MD -0.23, 95% CI -1.75 to 1.29, two studies, random-effects model). For respiratory symptoms, cough did not improve (SMD -0.05, 95% CI -0.66 to 0.56, two studies, random-effects model) but the sneezing score significantly improved (SMD -0.44, 95% CI -0.75 to -0.12, two studies, random-effects model). For outcomes related to the analgesic effects of NSAIDs (headache, ear pain, and muscle and joint pain) the treatment produced significant benefits. The risk of adverse effects was not high with NSAIDs (RR 2.94, 95% CI 0.51 to 17.03, two studies, random-effects model) and it is difficult to conclude that such drugs are not different from placebo. NSAIDs are somewhat effective in relieving discomfort caused by a cold but there is no clear evidence of their effect in easing respiratory symptoms. The balance of benefit and harms needs to be considered when using NSAIDs for colds.

Systematic review on the health effects of exposure to radiofrequency electromagnetic fields from mobile phone base stations

PubMed Central

Frei, Patrizia; Mohler, Evelyn; Hug, Kerstin

2010-01-01

Abstract Objective To review and evaluate the recent literature on the health effects of exposure to mobile phone base station (MPBS) radiation. Methods We performed a systematic review of randomized human trials conducted in laboratory settings and of epidemiological studies that investigated the health effects of MPBS radiation in the everyday environment. Findings We included in the analysis 17 articles that met our basic quality criteria: 5 randomized human laboratory trials and 12 epidemiological studies. The majority of the papers (14) examined self-reported non-specific symptoms of ill-health. Most of the randomized trials did not detect any association between MPBS radiation and the development of acute symptoms during or shortly after exposure. The sporadically observed associations did not show a consistent pattern with regard to symptoms or types of exposure. We also found that the more sophisticated the exposure assessment, the less likely it was that an effect would be reported. Studies on health effects other than non-specific symptoms and studies on MPBS exposure in children were scarce. Conclusion The evidence for a missing relationship between MPBS exposure up to 10 volts per metre and acute symptom development can be considered strong because it is based on randomized, blinded human laboratory trials. At present, there is insufficient data to draw firm conclusions about health effects from long-term low-level exposure typically occurring in the everyday environment. PMID:21124713

Design paper: the DEMO trial: a randomized, parallel-group, observer-blinded clinical trial of aerobic versus non-aerobic versus relaxation training for patients with light to moderate depression.

PubMed

Krogh, Jesper; Petersen, Lone; Timmermann, Michael; Saltin, Bengt; Nordentoft, Merete

2007-01-01

In western countries, the yearly incidence of depression is estimated to be 3-5% and the lifetime prevalence is 17%. In patient populations with chronic diseases the point prevalence may be 20%. Depression is associated with increased risk for various conditions such as osteoporoses, cardiovascular diseases, and dementia. WHO stated in 2000 that depression was the fourth leading cause of disease burden in terms of disability. In 2000 the cost of depression in the US was estimated to 83 billion dollars. A predominance of trials suggests that physical exercise has a positive effect on depressive symptoms. However, a meta-analysis from 2001 stated: "The effectiveness of exercise in reducing symptoms of depression cannot be determined because of a lack of good quality research on clinical populations with adequate follow-up." The major objective for this randomized trial is to compare the effect of non-aerobic, aerobic, and relaxation training on depressive symptoms using the blindly assessed Hamilton depression scale (HAM-D(17)) as primary outcome. The secondary outcome is the effect of the intervention on working status (i.e., lost days from work, employed/unemployed) and the tertiary outcomes consist of biological responses. The trial is designed as a randomized, parallel-group, observer-blinded clinical trial. Patients are recruited through general practitioners and psychiatrist and randomized to three different interventions: 1) non-aerobic, -- progressive resistance training, 2) aerobic training, -- cardio respiratory fitness, and 3) relaxation training with minimal impact on strength or cardio respiratory fitness. Training for all three groups takes place twice a week for 4 months. Evaluation of patients' symptoms takes place four and 12 months after inclusion. The trial is designed to include 45 patients in each group. Statistical analysis will be done as intention to treat (all randomized patients). Results from the DEMO trial will be reported according to the CONSORT guidelines in 2008-2009.

Homeopathic Individualized Q-Potencies versus Fluoxetine for Moderate to Severe Depression: Double-Blind, Randomized Non-Inferiority Trial

PubMed Central

Adler, U. C.; Paiva, N. M. P.; Cesar, A. T.; Adler, M. S.; Molina, A.; Padula, A. E.; Calil, H. M.

2011-01-01

Homeopathy is a complementary and integrative medicine used in depression, The aim of this study is to investigate the non-inferiority and tolerability of individualized homeopathic medicines [Quinquagintamillesmial (Q-potencies)] in acute depression, using fluoxetine as active control. Ninety-one outpatients with moderate to severe depression were assigned to receive an individualized homeopathic medicine or fluoxetine 20 mg day−1 (up to 40 mg day−1) in a prospective, randomized, double-blind double-dummy 8-week, single-center trial. Primary efficacy measure was the analysis of the mean change in the Montgomery & Åsberg Depression Rating Scale (MADRS) depression scores, using a non-inferiority test with margin of 1.45. Secondary efficacy outcomes were response and remission rates. Tolerability was assessed with the side effect rating scale of the Scandinavian Society of Psychopharmacology. Mean MADRS scores differences were not significant at the 4th (P = .654) and 8th weeks (P = .965) of treatment. Non-inferiority of homeopathy was indicated because the upper limit of the confidence interval (CI) for mean difference in MADRS change was less than the non-inferiority margin: mean differences (homeopathy-fluoxetine) were −3.04 (95% CI −6.95, 0.86) and −2.4 (95% CI −6.05, 0.77) at 4th and 8th week, respectively. There were no significant differences between the percentages of response or remission rates in both groups. Tolerability: there were no significant differences between the side effects rates, although a higher percentage of patients treated with fluoxetine reported troublesome side effects and there was a trend toward greater treatment interruption for adverse effects in the fluoxetine group. This study illustrates the feasibility of randomized controlled double-blind trials of homeopathy in depression and indicates the non-inferiority of individualized homeopathic Q-potencies as compared to fluoxetine in acute treatment of outpatients with moderate to severe depression. PMID:19687192

Colonic stem cell data are consistent with the immortal model of stem cell division under non-random strand segregation.

PubMed

Walters, K

2009-06-01

Colonic stem cells are thought to reside towards the base of crypts of the colon, but their numbers and proliferation mechanisms are not well characterized. A defining property of stem cells is that they are able to divide asymmetrically, but it is not known whether they always divide asymmetrically (immortal model) or whether there are occasional symmetrical divisions (stochastic model). By measuring diversity of methylation patterns in colon crypt samples, a recent study found evidence in favour of the stochastic model, assuming random segregation of stem cell DNA strands during cell division. Here, the effect of preferential segregation of the template strand is considered to be consistent with the 'immortal strand hypothesis', and explore the effect on conclusions of previously published results. For a sample of crypts, it is shown how, under the immortal model, to calculate mean and variance of the number of unique methylation patterns allowing for non-random strand segregation and compare them with those observed. The calculated mean and variance are consistent with an immortal model that incorporates non-random strand segregation for a range of stem cell numbers and levels of preferential strand segregation. Allowing for preferential strand segregation considerably alters previously published conclusions relating to stem cell numbers and turnover mechanisms. Evidence in favour of the stochastic model may not be as strong as previously thought.

Are orange lollies effective in preventing nausea and vomiting related to dimethyl sulfoxide? A multicenter randomized trial.

PubMed

Gonella, Silvia; Berchialla, Paola; Bruno, Benedetto; Di Giulio, Paola

2014-09-01

Nausea and vomiting (NV) related to DMSO affect patients undergoing auto-SCT despite antiemetic measures. Orange flavoring may reduce gastrointestinal symptoms. A multicenter, randomized, three-arm, open-label trial in four Italian large bone marrow transplant centers was conducted to assess the effectiveness of orange aroma in preventing NV related to DMSO. Patients were randomized to orange ice lollies, non-citrus ice lollies, and routine treatment (deep breaths) during reinfusion. Data on NV were collected up to 5 days after infusion; 69/98 patients were randomized: 23 to orange, 21 to non-citrus ice lollies, and 25 to routine treatment. Although 48 h after transplantation no differences were observed in controlled nausea (Numerical Rating Scale (NRS) 0-100, ≤25) or vomiting, significantly fewer patients had no episodes of vomiting, no antiemetic rescue therapy, and no nausea (NRS <5) in the deep breath vs lollies groups (P = 0.017). The intensity of nausea over time differed significantly between ice lollies vs routine care (P = 0.001) groups, but not between the orange and non-citrus groups (P = 0.428). The vasoconstrictive action of ice may prevent NV related to DMSO in the acute phase and reduce the need for rescue antiemetic therapy. Ice lollies offer a simple, noninvasive, and economic means for relieving nausea and vomiting related to this preservative.

Compressed normalized block difference for object tracking

NASA Astrophysics Data System (ADS)

Gao, Yun; Zhang, Dengzhuo; Cai, Donglan; Zhou, Hao; Lan, Ge

2018-04-01

Feature extraction is very important for robust and real-time tracking. Compressive sensing provided a technical support for real-time feature extraction. However, all existing compressive tracking were based on compressed Haar-like feature, and how to compress many more excellent high-dimensional features is worth researching. In this paper, a novel compressed normalized block difference feature (CNBD) was proposed. For resisting noise effectively in a highdimensional normalized pixel difference feature (NPD), a normalized block difference feature extends two pixels in the original formula of NPD to two blocks. A CNBD feature can be obtained by compressing a normalized block difference feature based on compressive sensing theory, with the sparse random Gaussian matrix as the measurement matrix. The comparative experiments of 7 trackers on 20 challenging sequences showed that the tracker based on CNBD feature can perform better than other trackers, especially than FCT tracker based on compressed Haar-like feature, in terms of AUC, SR and Precision.

A comparison of the test-negative and the traditional case-control study designs for estimation of influenza vaccine effectiveness under nonrandom vaccination.

PubMed

Shi, Meng; An, Qian; Ainslie, Kylie E C; Haber, Michael; Orenstein, Walter A

2017-12-08

As annual influenza vaccination is recommended for all U.S. persons aged 6 months or older, it is unethical to conduct randomized clinical trials to estimate influenza vaccine effectiveness (VE). Observational studies are being increasingly used to estimate VE. We developed a probability model for comparing the bias and the precision of VE estimates from two case-control designs: the traditional case-control (TCC) design and the test-negative (TN) design. In both study designs, acute respiratory illness (ARI) patients seeking medical care testing positive for influenza infection are considered cases. In the TN design, ARI patients seeking medical care who test negative serve as controls, while in the TCC design, controls are randomly selected individuals from the community who did not contract an ARI. Our model assigns each study participant a covariate corresponding to the person's health status. The probabilities of vaccination and of contracting influenza and non-influenza ARI depend on health status. Hence, our model allows non-random vaccination and confounding. In addition, the probability of seeking care for ARI may depend on vaccination and health status. We consider two outcomes of interest: symptomatic influenza (SI) and medically-attended influenza (MAI). If vaccination does not affect the probability of non-influenza ARI, then VE estimates from TN studies usually have smaller bias than estimates from TCC studies. We also found that if vaccinated influenza ARI patients are less likely to seek medical care than unvaccinated patients because the vaccine reduces symptoms' severity, then estimates of VE from both types of studies may be severely biased when the outcome of interest is SI. The bias is not present when the outcome of interest is MAI. The TN design produces valid estimates of VE if (a) vaccination does not affect the probabilities of non-influenza ARI and of seeking care against influenza ARI, and (b) the confounding effects resulting from non-random vaccination are similar for influenza and non-influenza ARI. Since the bias of VE estimates depends on the outcome against which the vaccine is supposed to protect, it is important to specify the outcome of interest when evaluating the bias.

Comprehensive Analysis of Genome Rearrangements in Eight Human Malignant Tumor Tissues

PubMed Central

Wang, Chong

2016-01-01

Carcinogenesis is a complex multifactorial, multistage process, but the precise mechanisms are not well understood. In this study, we performed a genome-wide analysis of the copy number variation (CNV), breakpoint region (BPR) and fragile sites in 2,737 tumor samples from eight tumor entities and in 432 normal samples. CNV detection and BPR identification revealed that BPRs tended to accumulate in specific genomic regions in tumor samples whereas being dispersed genome-wide in the normal samples. Hotspots were observed, at which segments with similar alteration in copy number were overlapped along with BPRs adjacently clustered. Evaluation of BPR occurrence frequency showed that at least one was detected in about and more than 15% of samples for each tumor entity while BPRs were maximal in 12% of the normal samples. 127 of 2,716 tumor-relevant BPRs (termed ‘common BPRs’) exhibited also a noticeable occurrence frequency in the normal samples. Colocalization assessment identified 20,077 CNV-affecting genes and 169 of these being known tumor-related genes. The most noteworthy genes are KIAA0513 important for immunologic, synaptic and apoptotic signal pathways, intergenic non-coding RNA RP11-115C21.2 possibly acting as oncogene or tumor suppressor by changing the structure of chromatin, and ADAM32 likely importance in cancer cell proliferation and progression by ectodomain-shedding of diverse growth factors, and the well-known tumor suppressor gene p53. The BPR distributions indicate that CNV mutations are likely non-random in tumor genomes. The marked recurrence of BPRs at specific regions supports common progression mechanisms in tumors. The presence of hotspots together with common BPRs, despite its small group size, imply a relation between fragile sites and cancer-gene alteration. Our data further suggest that both protein-coding and non-coding genes possessing a range of biological functions might play a causative or functional role in tumor biology. This research enhances our understanding of the mechanisms for tumorigenesis and progression. PMID:27391163

Atherosclerosis and Liver Function Tests in Coronary Angiography Patients.

PubMed

Doganer, Y C; Rohrer, J E; Aydogan, U; Agerter, D C; Cayci, T; Barcin, C

2015-09-01

Elevated aminotransferase levels indicating liver function, even in the normal range, have attracted great concern as potential novel markers of cardiovascular risk assessment. We hypothesized the possibility that liver function test variations in the normal range might be meaningfully associated to coronary artery disease (CAD). Eighty-eight patients were randomly selected from those who underwent coronary angiography from June 2010 to June 2011 after applying to the outpatient cardiology clinic in Gulhane Military Medical Academy. According to the results of angiographies, patients were classified into three groups as normal, non-critical (< 50% involvement in coronaries), and critical (≥ 50% involvement in coronaries). In addition to angiographic intervention, measurements of serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) concentrations, albumin and the other serum parameters were performed in all patients. The patient groups of CAD were balanced (28 critical cases, 30 non-critical cases and 30 normal cases). Mean age was 51.93 ± 9.3 (range 32-65) years and 19.3 per cent (n = 17) were females. Multiple linear regression analysis of all three liver function tests explained a significant portion of the variance, but adjusted r-squares were small (AST = 0.174, ALT = 0.242, albumin = 0.124). Albumin was significantly higher for patients with critical CAD than for patients with no CAD (beta = 3.205, p = 0.002). Non-critical CAD was not significantly different from no CAD for any of the dependent variables. Mean AST was significantly higher for patients taking aspirin (beta = 0.218, p = 0.049), as was mean ALT (beta = 0.264, p = 0.015). Alanine aminotransferase and AST may not be associated with angiographically determined coronary atherosclerosis. Albumin may be more sensitive to demonstrate the burden of atherosclerosis. These results indicate that the association between the liver function tests and coronary atherosclerosis may be more complex than generally appreciated.

Topological resilience in non-normal networked systems

NASA Astrophysics Data System (ADS)

Asllani, Malbor; Carletti, Timoteo

2018-04-01

The network of interactions in complex systems strongly influences their resilience and the system capability to resist external perturbations or structural damages and to promptly recover thereafter. The phenomenon manifests itself in different domains, e.g., parasitic species invasion in ecosystems or cascade failures in human-made networks. Understanding the topological features of the networks that affect the resilience phenomenon remains a challenging goal for the design of robust complex systems. We hereby introduce the concept of non-normal networks, namely networks whose adjacency matrices are non-normal, propose a generating model, and show that such a feature can drastically change the global dynamics through an amplification of the system response to exogenous disturbances and eventually impact the system resilience. This early stage transient period can induce the formation of inhomogeneous patterns, even in systems involving a single diffusing agent, providing thus a new kind of dynamical instability complementary to the Turing one. We provide, first, an illustrative application of this result to ecology by proposing a mechanism to mute the Allee effect and, second, we propose a model of virus spreading in a population of commuters moving using a non-normal transport network, the London Tube.

Testing the Efficacy of Synthetic Vision during Non-Normal Operations as an Enabling Technology for Equivalent Visual Operations

NASA Technical Reports Server (NTRS)

Kramer, Lynda J.; Williams, Steven P.

2008-01-01

Synthetic Vision (SV) may serve as a revolutionary crew/vehicle interface enabling technology to meet the challenges of the Next Generation Air Transportation System Equivalent Visual Operations (EVO) concept that is, the ability to achieve or even improve on the safety of Visual Flight Rules (VFR) operations, maintain the operational tempos of VFR, and potentially retain VFR procedures independent of actual weather and visibility conditions. One significant challenge lies in the definition of required equipage on the aircraft and on the airport to enable the EVO concept objective. An experiment was conducted to evaluate the effects of the presence or absence of SV, the location (head-up or head-down) of this information during an instrument approach, and the type of airport lighting information on landing minima. Another key element of the testing entailed investigating the pilot s awareness and reaction to non-normal events (i.e., failure conditions) that were unexpectedly introduced into the experiment. These non-normals are critical determinants in the underlying safety of all-weather operations. This paper presents the experimental results specific to pilot response to non-normal events using head-up and head-down synthetic vision displays.

Conflicting results between randomized trials and observational studies on the impact of proton pump inhibitors on cardiovascular events when coadministered with dual antiplatelet therapy: systematic review.

PubMed

Melloni, Chiara; Washam, Jeffrey B; Jones, W Schuyler; Halim, Sharif A; Hasselblad, Victor; Mayer, Stephanie B; Heidenfelder, Brooke L; Dolor, Rowena J

2015-01-01

Discordant results have been reported on the effects of concomitant use of proton pump inhibitors (PPIs) and dual antiplatelet therapy (DAPT) for cardiovascular outcomes. We conducted a systematic review comparing the effectiveness and safety of concomitant use of PPIs and DAPT in the postdischarge treatment of unstable angina/non-ST-segment-elevation myocardial infarction patients. We searched for clinical studies in MEDLINE, EMBASE, and the Cochrane Database of Systematic Reviews, from 1995 to 2012. Reviewers screened and extracted data, assessed applicability and quality, and graded the strength of evidence. We performed meta-analyses of direct comparisons when outcomes and follow-up periods were comparable. Thirty-five studies were eligible. Five (4 randomized controlled trials and 1 observational) assessed the effect of omeprazole when added to DAPT; the other 30 (observational) assessed the effect of PPIs as a class when compared with no PPIs. Random-effects meta-analyses of the studies assessing PPIs as a class consistently reported higher event rates in patients receiving PPIs for various clinical outcomes at 1 year (composite ischemic end points, all-cause mortality, nonfatal MI, stroke, revascularization, and stent thrombosis). However, the results from randomized controlled trials evaluating omeprazole compared with placebo showed no difference in ischemic outcomes, despite a reduction in upper gastrointestinal bleeding with omeprazole. Large, well-conducted observational studies of PPIs and randomized controlled trials of omeprazole seem to provide conflicting results for the effect of PPIs on cardiovascular outcomes when coadministered with DAPT. Prospective trials that directly compare pharmacodynamic parameters and clinical events among specific PPI agents in patients with unstable angina/non-ST-segment-elevation myocardial infarction treated with DAPT are warranted. © 2015 American Heart Association, Inc.

Simulating Pre-Asymptotic, Non-Fickian Transport Although Doing Simple Random Walks - Supported By Empirical Pore-Scale Velocity Distributions and Memory Effects

NASA Astrophysics Data System (ADS)

Most, S.; Jia, N.; Bijeljic, B.; Nowak, W.

2016-12-01

Pre-asymptotic characteristics are almost ubiquitous when analyzing solute transport processes in porous media. These pre-asymptotic aspects are caused by spatial coherence in the velocity field and by its heterogeneity. For the Lagrangian perspective of particle displacements, the causes of pre-asymptotic, non-Fickian transport are skewed velocity distribution, statistical dependencies between subsequent increments of particle positions (memory) and dependence between the x, y and z-components of particle increments. Valid simulation frameworks should account for these factors. We propose a particle tracking random walk (PTRW) simulation technique that can use empirical pore-space velocity distributions as input, enforces memory between subsequent random walk steps, and considers cross dependence. Thus, it is able to simulate pre-asymptotic non-Fickian transport phenomena. Our PTRW framework contains an advection/dispersion term plus a diffusion term. The advection/dispersion term produces time-series of particle increments from the velocity CDFs. These time series are equipped with memory by enforcing that the CDF values of subsequent velocities change only slightly. The latter is achieved through a random walk on the axis of CDF values between 0 and 1. The virtual diffusion coefficient for that random walk is our only fitting parameter. Cross-dependence can be enforced by constraining the random walk to certain combinations of CDF values between the three velocity components in x, y and z. We will show that this modelling framework is capable of simulating non-Fickian transport by comparison with a pore-scale transport simulation and we analyze the approach to asymptotic behavior.

The Distribution of the Product Explains Normal Theory Mediation Confidence Interval Estimation.

PubMed

Kisbu-Sakarya, Yasemin; MacKinnon, David P; Miočević, Milica

2014-05-01

The distribution of the product has several useful applications. One of these applications is its use to form confidence intervals for the indirect effect as the product of 2 regression coefficients. The purpose of this article is to investigate how the moments of the distribution of the product explain normal theory mediation confidence interval coverage and imbalance. Values of the critical ratio for each random variable are used to demonstrate how the moments of the distribution of the product change across values of the critical ratio observed in research studies. Results of the simulation study showed that as skewness in absolute value increases, coverage decreases. And as skewness in absolute value and kurtosis increases, imbalance increases. The difference between testing the significance of the indirect effect using the normal theory versus the asymmetric distribution of the product is further illustrated with a real data example. This article is the first study to show the direct link between the distribution of the product and indirect effect confidence intervals and clarifies the results of previous simulation studies by showing why normal theory confidence intervals for indirect effects are often less accurate than those obtained from the asymmetric distribution of the product or from resampling methods.